Serveur d'exploration Covid (26 mars)

Attention, ce site est en cours de développement !
Attention, site généré par des moyens informatiques à partir de corpus bruts.
Les informations ne sont donc pas validées.

Comparison of Infant Gut and Skin Microbiota, Resistome and Virulome Between Neonatal Intensive Care Unit (NICU) Environments

Identifieur interne : 000865 ( Pmc/Corpus ); précédent : 000864; suivant : 000866

Comparison of Infant Gut and Skin Microbiota, Resistome and Virulome Between Neonatal Intensive Care Unit (NICU) Environments

Auteurs : Suchitra K. Hourigan ; Poorani Subramanian ; Nur A. Hasan ; Allison Ta ; Elisabeth Klein ; Nassim Chettout ; Kathi Huddleston ; Varsha Deopujari ; Shira Levy ; Rajiv Baveja ; Nicole C. Clemency ; Robin L. Baker ; John E. Niederhuber ; Rita R. Colwell

Source :

RBID : PMC:6026636

Abstract

Background: There is a growing move to provide care for premature infants in a single family, private room neonatal intensive care unit (NICU) in place of the traditional shared space, open bay NICU. The resultant effect on the developing neonatal microbiota is unknown.

Study Design: Stool and groin skin swabs were collected from infants in a shared-space NICU (old NICU) and a single-family room NICU (new NICU) on the same hospital campus. Metagenomic sequencing was performed and data analyzed by CosmosID bioinformatics software package.

Results: There were no significant differences between the cohorts in gestational age, length of stay, and delivery mode; infants in the old NICU received significantly more antibiotics (p = 0.03). Differentially abundant antimicrobial resistance genes and virulence associated genes were found between the cohorts in stool and skin, with more differentially abundant antimicrobial resistance genes in the new NICU. The entire bacterial microbiota analyzed to the genus level significantly differed between cohorts in skin (p = 0.0001) but not in stool samples. There was no difference in alpha diversity between the two cohorts. DNA viruses and fungi were detected but did not differ between cohorts.

Conclusion: Differences were seen in the resistome and virulome between the two cohorts with more differentially abundant antimicrobial resistance genes in the new NICU. This highlights the influence that different NICU environments can have on the neonatal microbiota. Whether the differences were due to the new NICU being a single-family NICU or located in a newly constructed building warrants exploration. Long term health outcomes from the differences observed must be followed longitudinally.


Url:
DOI: 10.3389/fmicb.2018.01361
PubMed: 29988506
PubMed Central: 6026636

Links to Exploration step

PMC:6026636

Le document en format XML

<record>
<TEI>
<teiHeader>
<fileDesc>
<titleStmt>
<title xml:lang="en">Comparison of Infant Gut and Skin Microbiota, Resistome and Virulome Between Neonatal Intensive Care Unit (NICU) Environments</title>
<author>
<name sortKey="Hourigan, Suchitra K" sort="Hourigan, Suchitra K" uniqKey="Hourigan S" first="Suchitra K." last="Hourigan">Suchitra K. Hourigan</name>
<affiliation>
<nlm:aff id="aff1">
<institution>Department of Pediatrics, Inova Children’s Hospital, Falls Church</institution>
,
<addr-line>VA</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
<affiliation>
<nlm:aff id="aff2">
<institution>Inova Translational Medicine Institute, Falls Church</institution>
,
<addr-line>VA</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
<affiliation>
<nlm:aff id="aff3">
<institution>Department of Pediatric Gastroenterology, Pediatric Specialists of Virginia, Fairfax</institution>
,
<addr-line>VA</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
</author>
<author>
<name sortKey="Subramanian, Poorani" sort="Subramanian, Poorani" uniqKey="Subramanian P" first="Poorani" last="Subramanian">Poorani Subramanian</name>
<affiliation>
<nlm:aff id="aff4">
<institution>CosmosID, Rockville</institution>
,
<addr-line>MD</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
</author>
<author>
<name sortKey="Hasan, Nur A" sort="Hasan, Nur A" uniqKey="Hasan N" first="Nur A." last="Hasan">Nur A. Hasan</name>
<affiliation>
<nlm:aff id="aff4">
<institution>CosmosID, Rockville</institution>
,
<addr-line>MD</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
</author>
<author>
<name sortKey="Ta, Allison" sort="Ta, Allison" uniqKey="Ta A" first="Allison" last="Ta">Allison Ta</name>
<affiliation>
<nlm:aff id="aff1">
<institution>Department of Pediatrics, Inova Children’s Hospital, Falls Church</institution>
,
<addr-line>VA</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
</author>
<author>
<name sortKey="Klein, Elisabeth" sort="Klein, Elisabeth" uniqKey="Klein E" first="Elisabeth" last="Klein">Elisabeth Klein</name>
<affiliation>
<nlm:aff id="aff2">
<institution>Inova Translational Medicine Institute, Falls Church</institution>
,
<addr-line>VA</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
</author>
<author>
<name sortKey="Chettout, Nassim" sort="Chettout, Nassim" uniqKey="Chettout N" first="Nassim" last="Chettout">Nassim Chettout</name>
<affiliation>
<nlm:aff id="aff2">
<institution>Inova Translational Medicine Institute, Falls Church</institution>
,
<addr-line>VA</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
</author>
<author>
<name sortKey="Huddleston, Kathi" sort="Huddleston, Kathi" uniqKey="Huddleston K" first="Kathi" last="Huddleston">Kathi Huddleston</name>
<affiliation>
<nlm:aff id="aff2">
<institution>Inova Translational Medicine Institute, Falls Church</institution>
,
<addr-line>VA</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
</author>
<author>
<name sortKey="Deopujari, Varsha" sort="Deopujari, Varsha" uniqKey="Deopujari V" first="Varsha" last="Deopujari">Varsha Deopujari</name>
<affiliation>
<nlm:aff id="aff2">
<institution>Inova Translational Medicine Institute, Falls Church</institution>
,
<addr-line>VA</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
</author>
<author>
<name sortKey="Levy, Shira" sort="Levy, Shira" uniqKey="Levy S" first="Shira" last="Levy">Shira Levy</name>
<affiliation>
<nlm:aff id="aff2">
<institution>Inova Translational Medicine Institute, Falls Church</institution>
,
<addr-line>VA</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
</author>
<author>
<name sortKey="Baveja, Rajiv" sort="Baveja, Rajiv" uniqKey="Baveja R" first="Rajiv" last="Baveja">Rajiv Baveja</name>
<affiliation>
<nlm:aff id="aff5">
<institution>Fairfax Neonatal Associates PC, Falls Church</institution>
,
<addr-line>VA</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
</author>
<author>
<name sortKey="Clemency, Nicole C" sort="Clemency, Nicole C" uniqKey="Clemency N" first="Nicole C." last="Clemency">Nicole C. Clemency</name>
<affiliation>
<nlm:aff id="aff2">
<institution>Inova Translational Medicine Institute, Falls Church</institution>
,
<addr-line>VA</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
</author>
<author>
<name sortKey="Baker, Robin L" sort="Baker, Robin L" uniqKey="Baker R" first="Robin L." last="Baker">Robin L. Baker</name>
<affiliation>
<nlm:aff id="aff5">
<institution>Fairfax Neonatal Associates PC, Falls Church</institution>
,
<addr-line>VA</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
</author>
<author>
<name sortKey="Niederhuber, John E" sort="Niederhuber, John E" uniqKey="Niederhuber J" first="John E." last="Niederhuber">John E. Niederhuber</name>
<affiliation>
<nlm:aff id="aff2">
<institution>Inova Translational Medicine Institute, Falls Church</institution>
,
<addr-line>VA</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
</author>
<author>
<name sortKey="Colwell, Rita R" sort="Colwell, Rita R" uniqKey="Colwell R" first="Rita R." last="Colwell">Rita R. Colwell</name>
<affiliation>
<nlm:aff id="aff4">
<institution>CosmosID, Rockville</institution>
,
<addr-line>MD</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
</author>
</titleStmt>
<publicationStmt>
<idno type="wicri:source">PMC</idno>
<idno type="pmid">29988506</idno>
<idno type="pmc">6026636</idno>
<idno type="url">http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6026636</idno>
<idno type="RBID">PMC:6026636</idno>
<idno type="doi">10.3389/fmicb.2018.01361</idno>
<date when="2018">2018</date>
<idno type="wicri:Area/Pmc/Corpus">000865</idno>
<idno type="wicri:explorRef" wicri:stream="Pmc" wicri:step="Corpus" wicri:corpus="PMC">000865</idno>
</publicationStmt>
<sourceDesc>
<biblStruct>
<analytic>
<title xml:lang="en" level="a" type="main">Comparison of Infant Gut and Skin Microbiota, Resistome and Virulome Between Neonatal Intensive Care Unit (NICU) Environments</title>
<author>
<name sortKey="Hourigan, Suchitra K" sort="Hourigan, Suchitra K" uniqKey="Hourigan S" first="Suchitra K." last="Hourigan">Suchitra K. Hourigan</name>
<affiliation>
<nlm:aff id="aff1">
<institution>Department of Pediatrics, Inova Children’s Hospital, Falls Church</institution>
,
<addr-line>VA</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
<affiliation>
<nlm:aff id="aff2">
<institution>Inova Translational Medicine Institute, Falls Church</institution>
,
<addr-line>VA</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
<affiliation>
<nlm:aff id="aff3">
<institution>Department of Pediatric Gastroenterology, Pediatric Specialists of Virginia, Fairfax</institution>
,
<addr-line>VA</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
</author>
<author>
<name sortKey="Subramanian, Poorani" sort="Subramanian, Poorani" uniqKey="Subramanian P" first="Poorani" last="Subramanian">Poorani Subramanian</name>
<affiliation>
<nlm:aff id="aff4">
<institution>CosmosID, Rockville</institution>
,
<addr-line>MD</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
</author>
<author>
<name sortKey="Hasan, Nur A" sort="Hasan, Nur A" uniqKey="Hasan N" first="Nur A." last="Hasan">Nur A. Hasan</name>
<affiliation>
<nlm:aff id="aff4">
<institution>CosmosID, Rockville</institution>
,
<addr-line>MD</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
</author>
<author>
<name sortKey="Ta, Allison" sort="Ta, Allison" uniqKey="Ta A" first="Allison" last="Ta">Allison Ta</name>
<affiliation>
<nlm:aff id="aff1">
<institution>Department of Pediatrics, Inova Children’s Hospital, Falls Church</institution>
,
<addr-line>VA</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
</author>
<author>
<name sortKey="Klein, Elisabeth" sort="Klein, Elisabeth" uniqKey="Klein E" first="Elisabeth" last="Klein">Elisabeth Klein</name>
<affiliation>
<nlm:aff id="aff2">
<institution>Inova Translational Medicine Institute, Falls Church</institution>
,
<addr-line>VA</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
</author>
<author>
<name sortKey="Chettout, Nassim" sort="Chettout, Nassim" uniqKey="Chettout N" first="Nassim" last="Chettout">Nassim Chettout</name>
<affiliation>
<nlm:aff id="aff2">
<institution>Inova Translational Medicine Institute, Falls Church</institution>
,
<addr-line>VA</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
</author>
<author>
<name sortKey="Huddleston, Kathi" sort="Huddleston, Kathi" uniqKey="Huddleston K" first="Kathi" last="Huddleston">Kathi Huddleston</name>
<affiliation>
<nlm:aff id="aff2">
<institution>Inova Translational Medicine Institute, Falls Church</institution>
,
<addr-line>VA</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
</author>
<author>
<name sortKey="Deopujari, Varsha" sort="Deopujari, Varsha" uniqKey="Deopujari V" first="Varsha" last="Deopujari">Varsha Deopujari</name>
<affiliation>
<nlm:aff id="aff2">
<institution>Inova Translational Medicine Institute, Falls Church</institution>
,
<addr-line>VA</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
</author>
<author>
<name sortKey="Levy, Shira" sort="Levy, Shira" uniqKey="Levy S" first="Shira" last="Levy">Shira Levy</name>
<affiliation>
<nlm:aff id="aff2">
<institution>Inova Translational Medicine Institute, Falls Church</institution>
,
<addr-line>VA</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
</author>
<author>
<name sortKey="Baveja, Rajiv" sort="Baveja, Rajiv" uniqKey="Baveja R" first="Rajiv" last="Baveja">Rajiv Baveja</name>
<affiliation>
<nlm:aff id="aff5">
<institution>Fairfax Neonatal Associates PC, Falls Church</institution>
,
<addr-line>VA</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
</author>
<author>
<name sortKey="Clemency, Nicole C" sort="Clemency, Nicole C" uniqKey="Clemency N" first="Nicole C." last="Clemency">Nicole C. Clemency</name>
<affiliation>
<nlm:aff id="aff2">
<institution>Inova Translational Medicine Institute, Falls Church</institution>
,
<addr-line>VA</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
</author>
<author>
<name sortKey="Baker, Robin L" sort="Baker, Robin L" uniqKey="Baker R" first="Robin L." last="Baker">Robin L. Baker</name>
<affiliation>
<nlm:aff id="aff5">
<institution>Fairfax Neonatal Associates PC, Falls Church</institution>
,
<addr-line>VA</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
</author>
<author>
<name sortKey="Niederhuber, John E" sort="Niederhuber, John E" uniqKey="Niederhuber J" first="John E." last="Niederhuber">John E. Niederhuber</name>
<affiliation>
<nlm:aff id="aff2">
<institution>Inova Translational Medicine Institute, Falls Church</institution>
,
<addr-line>VA</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
</author>
<author>
<name sortKey="Colwell, Rita R" sort="Colwell, Rita R" uniqKey="Colwell R" first="Rita R." last="Colwell">Rita R. Colwell</name>
<affiliation>
<nlm:aff id="aff4">
<institution>CosmosID, Rockville</institution>
,
<addr-line>MD</addr-line>
,
<country>United States</country>
</nlm:aff>
</affiliation>
</author>
</analytic>
<series>
<title level="j">Frontiers in Microbiology</title>
<idno type="eISSN">1664-302X</idno>
<imprint>
<date when="2018">2018</date>
</imprint>
</series>
</biblStruct>
</sourceDesc>
</fileDesc>
<profileDesc>
<textClass></textClass>
</profileDesc>
</teiHeader>
<front>
<div type="abstract" xml:lang="en">
<p>
<bold>Background:</bold>
There is a growing move to provide care for premature infants in a single family, private room neonatal intensive care unit (NICU) in place of the traditional shared space, open bay NICU. The resultant effect on the developing neonatal microbiota is unknown.</p>
<p>
<bold>Study Design:</bold>
Stool and groin skin swabs were collected from infants in a shared-space NICU (old NICU) and a single-family room NICU (new NICU) on the same hospital campus. Metagenomic sequencing was performed and data analyzed by CosmosID bioinformatics software package.</p>
<p>
<bold>Results:</bold>
There were no significant differences between the cohorts in gestational age, length of stay, and delivery mode; infants in the old NICU received significantly more antibiotics (
<italic>p</italic>
= 0.03). Differentially abundant antimicrobial resistance genes and virulence associated genes were found between the cohorts in stool and skin, with more differentially abundant antimicrobial resistance genes in the new NICU. The entire bacterial microbiota analyzed to the genus level significantly differed between cohorts in skin (
<italic>p</italic>
= 0.0001) but not in stool samples. There was no difference in alpha diversity between the two cohorts. DNA viruses and fungi were detected but did not differ between cohorts.</p>
<p>
<bold>Conclusion:</bold>
Differences were seen in the resistome and virulome between the two cohorts with more differentially abundant antimicrobial resistance genes in the new NICU. This highlights the influence that different NICU environments can have on the neonatal microbiota. Whether the differences were due to the new NICU being a single-family NICU or located in a newly constructed building warrants exploration. Long term health outcomes from the differences observed must be followed longitudinally.</p>
</div>
</front>
<back>
<div1 type="bibliography">
<listBibl>
<biblStruct>
<analytic>
<author>
<name sortKey="Bi, R" uniqKey="Bi R">R. Bi</name>
</author>
<author>
<name sortKey="Liu, P" uniqKey="Liu P">P. Liu</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Boyle, E M" uniqKey="Boyle E">E. M. Boyle</name>
</author>
<author>
<name sortKey="Poulsen, G" uniqKey="Poulsen G">G. Poulsen</name>
</author>
<author>
<name sortKey="Field, G J" uniqKey="Field G">G. J. Field</name>
</author>
<author>
<name sortKey="Kurinczuk, J J" uniqKey="Kurinczuk J">J. J. Kurinczuk</name>
</author>
<author>
<name sortKey="Wolke, D" uniqKey="Wolke D">D. Wolke</name>
</author>
<author>
<name sortKey="Alfirevic, Z" uniqKey="Alfirevic Z">Z. Alfirevic</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Brooks, B" uniqKey="Brooks B">B. Brooks</name>
</author>
<author>
<name sortKey="Firek, B A" uniqKey="Firek B">B. A. Firek</name>
</author>
<author>
<name sortKey="Miller, C S" uniqKey="Miller C">C. S. Miller</name>
</author>
<author>
<name sortKey="Sharon, I" uniqKey="Sharon I">I. Sharon</name>
</author>
<author>
<name sortKey="Thomas, B C" uniqKey="Thomas B">B. C. Thomas</name>
</author>
<author>
<name sortKey="Baker, R" uniqKey="Baker R">R. Baker</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Capone, K A" uniqKey="Capone K">K. A. Capone</name>
</author>
<author>
<name sortKey="Dowd, S E" uniqKey="Dowd S">S. E. Dowd</name>
</author>
<author>
<name sortKey="Stamatas, G N" uniqKey="Stamatas G">G. N. Stamatas</name>
</author>
<author>
<name sortKey="Nikolovski, J" uniqKey="Nikolovski J">J. Nikolovski</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Collins, S M" uniqKey="Collins S">S. M. Collins</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Cong, X" uniqKey="Cong X">X. Cong</name>
</author>
<author>
<name sortKey="Xu, W" uniqKey="Xu W">W. Xu</name>
</author>
<author>
<name sortKey="Janton, S" uniqKey="Janton S">S. Janton</name>
</author>
<author>
<name sortKey="Henderson, W A" uniqKey="Henderson W">W. A. Henderson</name>
</author>
<author>
<name sortKey="Matson, A" uniqKey="Matson A">A. Matson</name>
</author>
<author>
<name sortKey="Mcgrath, J M" uniqKey="Mcgrath J">J. M. McGrath</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Costello, E K" uniqKey="Costello E">E. K. Costello</name>
</author>
<author>
<name sortKey="Carlisle, E M" uniqKey="Carlisle E">E. M. Carlisle</name>
</author>
<author>
<name sortKey="Bik, E M" uniqKey="Bik E">E. M. Bik</name>
</author>
<author>
<name sortKey="Morowitz, M J" uniqKey="Morowitz M">M. J. Morowitz</name>
</author>
<author>
<name sortKey="Relman, D A" uniqKey="Relman D">D. A. Relman</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="De Boer, R" uniqKey="De Boer R">R. de Boer</name>
</author>
<author>
<name sortKey="Peters, R" uniqKey="Peters R">R. Peters</name>
</author>
<author>
<name sortKey="Gierveld, S" uniqKey="Gierveld S">S. Gierveld</name>
</author>
<author>
<name sortKey="Schuurman, T" uniqKey="Schuurman T">T. Schuurman</name>
</author>
<author>
<name sortKey="Kooistra Smid, M" uniqKey="Kooistra Smid M">M. Kooistra-Smid</name>
</author>
<author>
<name sortKey="Savelkoul, P" uniqKey="Savelkoul P">P. Savelkoul</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Domanico, R" uniqKey="Domanico R">R. Domanico</name>
</author>
<author>
<name sortKey="Davis, D K" uniqKey="Davis D">D. K. Davis</name>
</author>
<author>
<name sortKey="Coleman, F" uniqKey="Coleman F">F. Coleman</name>
</author>
<author>
<name sortKey="Davis, B O" uniqKey="Davis B">B. O. Davis</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Echarri, P P" uniqKey="Echarri P">P. P. Echarri</name>
</author>
<author>
<name sortKey="Gracia, C M" uniqKey="Gracia C">C. M. Graciá</name>
</author>
<author>
<name sortKey="Berruezo, G R" uniqKey="Berruezo G">G. R. Berruezo</name>
</author>
<author>
<name sortKey="Vives, I" uniqKey="Vives I">I. Vives</name>
</author>
<author>
<name sortKey="Ballesta, M" uniqKey="Ballesta M">M. Ballesta</name>
</author>
<author>
<name sortKey="Solis, G" uniqKey="Solis G">G. Solís</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Fallani, M" uniqKey="Fallani M">M. Fallani</name>
</author>
<author>
<name sortKey="Young, D" uniqKey="Young D">D. Young</name>
</author>
<author>
<name sortKey="Scott, J" uniqKey="Scott J">J. Scott</name>
</author>
<author>
<name sortKey="Norin, E" uniqKey="Norin E">E. Norin</name>
</author>
<author>
<name sortKey="Amarri, S" uniqKey="Amarri S">S. Amarri</name>
</author>
<author>
<name sortKey="Adam, R" uniqKey="Adam R">R. Adam</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Fan, W" uniqKey="Fan W">W. Fan</name>
</author>
<author>
<name sortKey="Li, X" uniqKey="Li X">X. Li</name>
</author>
<author>
<name sortKey="Yang, L" uniqKey="Yang L">L. Yang</name>
</author>
<author>
<name sortKey="Huo, G" uniqKey="Huo G">G. Huo</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Frank, D N" uniqKey="Frank D">D. N. Frank</name>
</author>
<author>
<name sortKey="St Amand, A L" uniqKey="St Amand A">A. L. St Amand</name>
</author>
<author>
<name sortKey="Feldman, R A" uniqKey="Feldman R">R. A. Feldman</name>
</author>
<author>
<name sortKey="Boedeker, E C" uniqKey="Boedeker E">E. C. Boedeker</name>
</author>
<author>
<name sortKey="Harpaz, N" uniqKey="Harpaz N">N. Harpaz</name>
</author>
<author>
<name sortKey="Pace, N R" uniqKey="Pace N">N. R. Pace</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Fujimura, K E" uniqKey="Fujimura K">K. E. Fujimura</name>
</author>
<author>
<name sortKey="Demoor, T" uniqKey="Demoor T">T. Demoor</name>
</author>
<author>
<name sortKey="Rauch, M" uniqKey="Rauch M">M. Rauch</name>
</author>
<author>
<name sortKey="Faruqi, A A" uniqKey="Faruqi A">A. A. Faruqi</name>
</author>
<author>
<name sortKey="Jang, S" uniqKey="Jang S">S. Jang</name>
</author>
<author>
<name sortKey="Johnson, C C" uniqKey="Johnson C">C. C. Johnson</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Gasparrini, A J" uniqKey="Gasparrini A">A. J. Gasparrini</name>
</author>
<author>
<name sortKey="Crofts, T S" uniqKey="Crofts T">T. S. Crofts</name>
</author>
<author>
<name sortKey="Gibson, M K" uniqKey="Gibson M">M. K. Gibson</name>
</author>
<author>
<name sortKey="Tarr, P I" uniqKey="Tarr P">P. I. Tarr</name>
</author>
<author>
<name sortKey="Warner, B B" uniqKey="Warner B">B. B. Warner</name>
</author>
<author>
<name sortKey="Dantas, G" uniqKey="Dantas G">G. Dantas</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Gaujoux, R" uniqKey="Gaujoux R">R. Gaujoux</name>
</author>
<author>
<name sortKey="Seoighe, C" uniqKey="Seoighe C">C. Seoighe</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Gibson, M K" uniqKey="Gibson M">M. K. Gibson</name>
</author>
<author>
<name sortKey="Wang, B" uniqKey="Wang B">B. Wang</name>
</author>
<author>
<name sortKey="Ahmadi, S" uniqKey="Ahmadi S">S. Ahmadi</name>
</author>
<author>
<name sortKey="Burnham, C" uniqKey="Burnham C">C. Burnham</name>
</author>
<author>
<name sortKey="Tarr, P I" uniqKey="Tarr P">P. I. Tarr</name>
</author>
<author>
<name sortKey="Warner, B B" uniqKey="Warner B">B. B. Warner</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Hasan, N A" uniqKey="Hasan N">N. A. Hasan</name>
</author>
<author>
<name sortKey="Young, B A" uniqKey="Young B">B. A. Young</name>
</author>
<author>
<name sortKey="Minard Smith, A T" uniqKey="Minard Smith A">A. T. Minard-Smith</name>
</author>
<author>
<name sortKey="Saeed, K" uniqKey="Saeed K">K. Saeed</name>
</author>
<author>
<name sortKey="Li, H" uniqKey="Li H">H. Li</name>
</author>
<author>
<name sortKey="Heizer, E M" uniqKey="Heizer E">E. M. Heizer</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Hewitt, K M" uniqKey="Hewitt K">K. M. Hewitt</name>
</author>
<author>
<name sortKey="Mannino, F L" uniqKey="Mannino F">F. L. Mannino</name>
</author>
<author>
<name sortKey="Gonzalez, A" uniqKey="Gonzalez A">A. Gonzalez</name>
</author>
<author>
<name sortKey="Chase, J H" uniqKey="Chase J">J. H. Chase</name>
</author>
<author>
<name sortKey="Caporaso, J G" uniqKey="Caporaso J">J. G. Caporaso</name>
</author>
<author>
<name sortKey="Knight, R" uniqKey="Knight R">R. Knight</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Hsiao, E Y" uniqKey="Hsiao E">E. Y. Hsiao</name>
</author>
<author>
<name sortKey="Mcbride, S W" uniqKey="Mcbride S">S. W. McBride</name>
</author>
<author>
<name sortKey="Hsien, S" uniqKey="Hsien S">S. Hsien</name>
</author>
<author>
<name sortKey="Sharon, G" uniqKey="Sharon G">G. Sharon</name>
</author>
<author>
<name sortKey="Hyde, E R" uniqKey="Hyde E">E. R. Hyde</name>
</author>
<author>
<name sortKey="Mccue, T" uniqKey="Mccue T">T. McCue</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Dodge, Y" uniqKey="Dodge Y">Y. Dodge</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Kennedy, E A" uniqKey="Kennedy E">E. A. Kennedy</name>
</author>
<author>
<name sortKey="Connolly, J" uniqKey="Connolly J">J. Connolly</name>
</author>
<author>
<name sortKey="Hourihane, J O" uniqKey="Hourihane J">J. O. Hourihane</name>
</author>
<author>
<name sortKey="Fallon, P G" uniqKey="Fallon P">P. G. Fallon</name>
</author>
<author>
<name sortKey="Mclean, W H I" uniqKey="Mclean W">W. H. I. McLean</name>
</author>
<author>
<name sortKey="Murray, D" uniqKey="Murray D">D. Murray</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Khelaifia, S" uniqKey="Khelaifia S">S. Khelaifia</name>
</author>
<author>
<name sortKey="Ramonet, P Y" uniqKey="Ramonet P">P.-Y. Ramonet</name>
</author>
<author>
<name sortKey="Bedotto Buffet, M" uniqKey="Bedotto Buffet M">M. Bedotto Buffet</name>
</author>
<author>
<name sortKey="Drancourt, M" uniqKey="Drancourt M">M. Drancourt</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="La Rosa, P S" uniqKey="La Rosa P">P. S. La Rosa</name>
</author>
<author>
<name sortKey="Brooks, J P" uniqKey="Brooks J">J. P. Brooks</name>
</author>
<author>
<name sortKey="Deych, E" uniqKey="Deych E">E. Deych</name>
</author>
<author>
<name sortKey="Boone, E L" uniqKey="Boone E">E. L. Boone</name>
</author>
<author>
<name sortKey="Edwards, D J" uniqKey="Edwards D">D. J. Edwards</name>
</author>
<author>
<name sortKey="Wang, Q" uniqKey="Wang Q">Q. Wang</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="La Rosa, P S" uniqKey="La Rosa P">P. S. La Rosa</name>
</author>
<author>
<name sortKey="Warner, B B" uniqKey="Warner B">B. B. Warner</name>
</author>
<author>
<name sortKey="Zhou, Y" uniqKey="Zhou Y">Y. Zhou</name>
</author>
<author>
<name sortKey="Weinstock, G M" uniqKey="Weinstock G">G. M. Weinstock</name>
</author>
<author>
<name sortKey="Sodergren, E" uniqKey="Sodergren E">E. Sodergren</name>
</author>
<author>
<name sortKey="Hall Moore, C M" uniqKey="Hall Moore C">C. M. Hall-Moore</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Lax, S" uniqKey="Lax S">S. Lax</name>
</author>
<author>
<name sortKey="Sangwan, N" uniqKey="Sangwan N">N. Sangwan</name>
</author>
<author>
<name sortKey="Smith, D" uniqKey="Smith D">D. Smith</name>
</author>
<author>
<name sortKey="Larsen, P" uniqKey="Larsen P">P. Larsen</name>
</author>
<author>
<name sortKey="Handley, K M" uniqKey="Handley K">K. M. Handley</name>
</author>
<author>
<name sortKey="Richardson, M" uniqKey="Richardson M">M. Richardson</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Lax, S" uniqKey="Lax S">S. Lax</name>
</author>
<author>
<name sortKey="Smith, D P" uniqKey="Smith D">D. P. Smith</name>
</author>
<author>
<name sortKey="Marcell, J H" uniqKey="Marcell J">J. H. Marcell</name>
</author>
<author>
<name sortKey="Owens, S" uniqKey="Owens S">S. Owens</name>
</author>
<author>
<name sortKey="Handley, K" uniqKey="Handley K">K. Handley</name>
</author>
<author>
<name sortKey="Scott, K" uniqKey="Scott K">K. Scott</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Manichanh, C" uniqKey="Manichanh C">C. Manichanh</name>
</author>
<author>
<name sortKey="Borruel, N" uniqKey="Borruel N">N. Borruel</name>
</author>
<author>
<name sortKey="Casellas, F" uniqKey="Casellas F">F. Casellas</name>
</author>
<author>
<name sortKey="Guarner, F" uniqKey="Guarner F">F. Guarner</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Marks, L R" uniqKey="Marks L">L. R. Marks</name>
</author>
<author>
<name sortKey="Clementi, E A" uniqKey="Clementi E">E. A. Clementi</name>
</author>
<author>
<name sortKey="Hakansson, A P" uniqKey="Hakansson A">A. P. Hakansson</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Mcgill, R" uniqKey="Mcgill R">R. McGill</name>
</author>
<author>
<name sortKey="Tukey, J W" uniqKey="Tukey J">J. W. Tukey</name>
</author>
<author>
<name sortKey="Larsen, W A" uniqKey="Larsen W">W. A. Larsen</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Moles, L" uniqKey="Moles L">L. Moles</name>
</author>
<author>
<name sortKey="G Mez, M" uniqKey="G Mez M">M. Gómez</name>
</author>
<author>
<name sortKey="Heilig, H" uniqKey="Heilig H">H. Heilig</name>
</author>
<author>
<name sortKey="Bustos, G" uniqKey="Bustos G">G. Bustos</name>
</author>
<author>
<name sortKey="Fuentes, S" uniqKey="Fuentes S">S. Fuentes</name>
</author>
<author>
<name sortKey="De Vos, W" uniqKey="De Vos W">W. de Vos</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Moles, L" uniqKey="Moles L">L. Moles</name>
</author>
<author>
<name sortKey="G Mez, M" uniqKey="G Mez M">M. Gómez</name>
</author>
<author>
<name sortKey="Jimenez, E" uniqKey="Jimenez E">E. Jiménez</name>
</author>
<author>
<name sortKey="Fernandez, L" uniqKey="Fernandez L">L. Fernández</name>
</author>
<author>
<name sortKey="Bustos, G" uniqKey="Bustos G">G. Bustos</name>
</author>
<author>
<name sortKey="Chaves, F" uniqKey="Chaves F">F. Chaves</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Ortenstrand, A" uniqKey="Ortenstrand A">A. Ortenstrand</name>
</author>
<author>
<name sortKey="Westrup, B" uniqKey="Westrup B">B. Westrup</name>
</author>
<author>
<name sortKey="Brostrom, E B" uniqKey="Brostrom E">E. B. Broström</name>
</author>
<author>
<name sortKey="Sarman, I" uniqKey="Sarman I">I. Sarman</name>
</author>
<author>
<name sortKey="Akerstrom, S" uniqKey="Akerstrom S">S. Akerström</name>
</author>
<author>
<name sortKey="Brune, T" uniqKey="Brune T">T. Brune</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Pammi, M" uniqKey="Pammi M">M. Pammi</name>
</author>
<author>
<name sortKey="Cope, J" uniqKey="Cope J">J. Cope</name>
</author>
<author>
<name sortKey="Tarr, P I" uniqKey="Tarr P">P. I. Tarr</name>
</author>
<author>
<name sortKey="Warner, B B" uniqKey="Warner B">B. B. Warner</name>
</author>
<author>
<name sortKey="Morrow, A L" uniqKey="Morrow A">A. L. Morrow</name>
</author>
<author>
<name sortKey="Mai, V" uniqKey="Mai V">V. Mai</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Pammi, M" uniqKey="Pammi M">M. Pammi</name>
</author>
<author>
<name sortKey="O Rien, J L" uniqKey="O Rien J">J. L. O’Brien</name>
</author>
<author>
<name sortKey="Ajami, N J" uniqKey="Ajami N">N. J. Ajami</name>
</author>
<author>
<name sortKey="Wong, M C" uniqKey="Wong M">M. C. Wong</name>
</author>
<author>
<name sortKey="Versalovic, J" uniqKey="Versalovic J">J. Versalovic</name>
</author>
<author>
<name sortKey="Petrosino, J F" uniqKey="Petrosino J">J. F. Petrosino</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Ponnusamy, D" uniqKey="Ponnusamy D">D. Ponnusamy</name>
</author>
<author>
<name sortKey="Kozlova, E V" uniqKey="Kozlova E">E. V. Kozlova</name>
</author>
<author>
<name sortKey="Sha, J" uniqKey="Sha J">J. Sha</name>
</author>
<author>
<name sortKey="Erova, T E" uniqKey="Erova T">T. E. Erova</name>
</author>
<author>
<name sortKey="Azar, S R" uniqKey="Azar S">S. R. Azar</name>
</author>
<author>
<name sortKey="Fitts, E C" uniqKey="Fitts E">E. C. Fitts</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Sadatsafavi, H" uniqKey="Sadatsafavi H">H. Sadatsafavi</name>
</author>
<author>
<name sortKey="Niknejad, B" uniqKey="Niknejad B">B. Niknejad</name>
</author>
<author>
<name sortKey="Shepley, M" uniqKey="Shepley M">M. Shepley</name>
</author>
<author>
<name sortKey="Sadatsafavi, M" uniqKey="Sadatsafavi M">M. Sadatsafavi</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Saiman, L" uniqKey="Saiman L">L. Saiman</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Salonen, A" uniqKey="Salonen A">A. Salonen</name>
</author>
<author>
<name sortKey="Nikkil, J" uniqKey="Nikkil J">J. Nikkilä</name>
</author>
<author>
<name sortKey="Jalanka Tuovinen, J" uniqKey="Jalanka Tuovinen J">J. Jalanka-Tuovinen</name>
</author>
<author>
<name sortKey="Immonen, O" uniqKey="Immonen O">O. Immonen</name>
</author>
<author>
<name sortKey="Rajili Stojanovi, M" uniqKey="Rajili Stojanovi M">M. Rajilić-Stojanović</name>
</author>
<author>
<name sortKey="Kekkonen, R A" uniqKey="Kekkonen R">R. A. Kekkonen</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Stevens, D C" uniqKey="Stevens D">D. C. Stevens</name>
</author>
<author>
<name sortKey="Thompson, P A" uniqKey="Thompson P">P. A. Thompson</name>
</author>
<author>
<name sortKey="Helseth, C C" uniqKey="Helseth C">C. C. Helseth</name>
</author>
<author>
<name sortKey="Hsu, B" uniqKey="Hsu B">B. Hsu</name>
</author>
<author>
<name sortKey="Khan, M A" uniqKey="Khan M">M. A. Khan</name>
</author>
<author>
<name sortKey="Munson, D P" uniqKey="Munson D">D. P. Munson</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Tarkkanen, A M" uniqKey="Tarkkanen A">A. M. Tarkkanen</name>
</author>
<author>
<name sortKey="Heinonen, T" uniqKey="Heinonen T">T. Heinonen</name>
</author>
<author>
<name sortKey="J Gi, R" uniqKey="J Gi R">R. Jõgi</name>
</author>
<author>
<name sortKey="Mentula, S" uniqKey="Mentula S">S. Mentula</name>
</author>
<author>
<name sortKey="Van Der Rest, M E" uniqKey="Van Der Rest M">M. E. van der Rest</name>
</author>
<author>
<name sortKey="Donskey, C J" uniqKey="Donskey C">C. J. Donskey</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Tilg, H" uniqKey="Tilg H">H. Tilg</name>
</author>
<author>
<name sortKey="Kaser, A" uniqKey="Kaser A">A. Kaser</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Walsh, W F" uniqKey="Walsh W">W. F. Walsh</name>
</author>
<author>
<name sortKey="Mccullough, K L" uniqKey="Mccullough K">K. L. McCullough</name>
</author>
<author>
<name sortKey="White, R D" uniqKey="White R">R. D. White</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Wang, M" uniqKey="Wang M">M. Wang</name>
</author>
<author>
<name sortKey="Karlsson, C" uniqKey="Karlsson C">C. Karlsson</name>
</author>
<author>
<name sortKey="Olsson, C" uniqKey="Olsson C">C. Olsson</name>
</author>
<author>
<name sortKey="Adlerberth, I" uniqKey="Adlerberth I">I. Adlerberth</name>
</author>
<author>
<name sortKey="Wold, A E" uniqKey="Wold A">A. E. Wold</name>
</author>
<author>
<name sortKey="Strachan, D P" uniqKey="Strachan D">D. P. Strachan</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="West, C E" uniqKey="West C">C. E. West</name>
</author>
<author>
<name sortKey="Ryden, P" uniqKey="Ryden P">P. Rydén</name>
</author>
<author>
<name sortKey="Lundin, D" uniqKey="Lundin D">D. Lundin</name>
</author>
<author>
<name sortKey="Engstrand, L" uniqKey="Engstrand L">L. Engstrand</name>
</author>
<author>
<name sortKey="Tulic, M K" uniqKey="Tulic M">M. K. Tulic</name>
</author>
<author>
<name sortKey="Prescott, S L" uniqKey="Prescott S">S. L. Prescott</name>
</author>
</analytic>
</biblStruct>
<biblStruct>
<analytic>
<author>
<name sortKey="Yatsunenko, T" uniqKey="Yatsunenko T">T. Yatsunenko</name>
</author>
<author>
<name sortKey="Rey, F E" uniqKey="Rey F">F. E. Rey</name>
</author>
<author>
<name sortKey="Manary, M J" uniqKey="Manary M">M. J. Manary</name>
</author>
<author>
<name sortKey="Trehan, I" uniqKey="Trehan I">I. Trehan</name>
</author>
<author>
<name sortKey="Dominguez Bello, M G" uniqKey="Dominguez Bello M">M. G. Dominguez-Bello</name>
</author>
<author>
<name sortKey="Contreras, M" uniqKey="Contreras M">M. Contreras</name>
</author>
</analytic>
</biblStruct>
</listBibl>
</div1>
</back>
</TEI>
<pmc article-type="research-article">
<pmc-dir>properties open_access</pmc-dir>
<front>
<journal-meta>
<journal-id journal-id-type="nlm-ta">Front Microbiol</journal-id>
<journal-id journal-id-type="iso-abbrev">Front Microbiol</journal-id>
<journal-id journal-id-type="publisher-id">Front. Microbiol.</journal-id>
<journal-title-group>
<journal-title>Frontiers in Microbiology</journal-title>
</journal-title-group>
<issn pub-type="epub">1664-302X</issn>
<publisher>
<publisher-name>Frontiers Media S.A.</publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="pmid">29988506</article-id>
<article-id pub-id-type="pmc">6026636</article-id>
<article-id pub-id-type="doi">10.3389/fmicb.2018.01361</article-id>
<article-categories>
<subj-group subj-group-type="heading">
<subject>Microbiology</subject>
<subj-group>
<subject>Original Research</subject>
</subj-group>
</subj-group>
</article-categories>
<title-group>
<article-title>Comparison of Infant Gut and Skin Microbiota, Resistome and Virulome Between Neonatal Intensive Care Unit (NICU) Environments</article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname>Hourigan</surname>
<given-names>Suchitra K.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
<xref ref-type="aff" rid="aff3">
<sup>3</sup>
</xref>
<xref ref-type="corresp" rid="c001">
<sup>*</sup>
</xref>
<uri xlink:type="simple" xlink:href="http://loop.frontiersin.org/people/532369/overview"></uri>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Subramanian</surname>
<given-names>Poorani</given-names>
</name>
<xref ref-type="aff" rid="aff4">
<sup>4</sup>
</xref>
<uri xlink:type="simple" xlink:href="http://loop.frontiersin.org/people/410063/overview"></uri>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Hasan</surname>
<given-names>Nur A.</given-names>
</name>
<xref ref-type="aff" rid="aff4">
<sup>4</sup>
</xref>
<uri xlink:type="simple" xlink:href="http://loop.frontiersin.org/people/41541/overview"></uri>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Ta</surname>
<given-names>Allison</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Klein</surname>
<given-names>Elisabeth</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Chettout</surname>
<given-names>Nassim</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Huddleston</surname>
<given-names>Kathi</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Deopujari</surname>
<given-names>Varsha</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Levy</surname>
<given-names>Shira</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Baveja</surname>
<given-names>Rajiv</given-names>
</name>
<xref ref-type="aff" rid="aff5">
<sup>5</sup>
</xref>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Clemency</surname>
<given-names>Nicole C.</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
<uri xlink:type="simple" xlink:href="http://loop.frontiersin.org/people/572952/overview"></uri>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Baker</surname>
<given-names>Robin L.</given-names>
</name>
<xref ref-type="aff" rid="aff5">
<sup>5</sup>
</xref>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Niederhuber</surname>
<given-names>John E.</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Colwell</surname>
<given-names>Rita R.</given-names>
</name>
<xref ref-type="aff" rid="aff4">
<sup>4</sup>
</xref>
<uri xlink:type="simple" xlink:href="http://loop.frontiersin.org/people/79248/overview"></uri>
</contrib>
</contrib-group>
<aff id="aff1">
<sup>1</sup>
<institution>Department of Pediatrics, Inova Children’s Hospital, Falls Church</institution>
,
<addr-line>VA</addr-line>
,
<country>United States</country>
</aff>
<aff id="aff2">
<sup>2</sup>
<institution>Inova Translational Medicine Institute, Falls Church</institution>
,
<addr-line>VA</addr-line>
,
<country>United States</country>
</aff>
<aff id="aff3">
<sup>3</sup>
<institution>Department of Pediatric Gastroenterology, Pediatric Specialists of Virginia, Fairfax</institution>
,
<addr-line>VA</addr-line>
,
<country>United States</country>
</aff>
<aff id="aff4">
<sup>4</sup>
<institution>CosmosID, Rockville</institution>
,
<addr-line>MD</addr-line>
,
<country>United States</country>
</aff>
<aff id="aff5">
<sup>5</sup>
<institution>Fairfax Neonatal Associates PC, Falls Church</institution>
,
<addr-line>VA</addr-line>
,
<country>United States</country>
</aff>
<author-notes>
<fn fn-type="edited-by">
<p>Edited by: Rakesh Sharma, Institute of Genomics and Integrative Biology (CSIR), India</p>
</fn>
<fn fn-type="edited-by">
<p>Reviewed by: Amedeo Amedei, Università degli Studi di Firenze, Italy; Mauricio J. Farfan, Universidad de Chile, Chile</p>
</fn>
<corresp id="c001">*Correspondence: Suchitra K. Hourigan,
<email>suchihourigan@gmail.com</email>
</corresp>
<fn fn-type="other" id="fn002">
<p>This article was submitted to Evolutionary and Genomic Microbiology, a section of the journal Frontiers in Microbiology</p>
</fn>
</author-notes>
<pub-date pub-type="epub">
<day>25</day>
<month>6</month>
<year>2018</year>
</pub-date>
<pub-date pub-type="collection">
<year>2018</year>
</pub-date>
<volume>9</volume>
<elocation-id>1361</elocation-id>
<history>
<date date-type="received">
<day>25</day>
<month>2</month>
<year>2018</year>
</date>
<date date-type="accepted">
<day>05</day>
<month>6</month>
<year>2018</year>
</date>
</history>
<permissions>
<copyright-statement>Copyright © 2018 Hourigan, Subramanian, Hasan, Ta, Klein, Chettout, Huddleston, Deopujari, Levy, Baveja, Clemency, Baker, Niederhuber and Colwell.</copyright-statement>
<copyright-year>2018</copyright-year>
<copyright-holder>Hourigan, Subramanian, Hasan, Ta, Klein, Chettout, Huddleston, Deopujari, Levy, Baveja, Clemency, Baker, Niederhuber and Colwell</copyright-holder>
<license xlink:href="http://creativecommons.org/licenses/by/4.0/">
<license-p>This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.</license-p>
</license>
</permissions>
<abstract>
<p>
<bold>Background:</bold>
There is a growing move to provide care for premature infants in a single family, private room neonatal intensive care unit (NICU) in place of the traditional shared space, open bay NICU. The resultant effect on the developing neonatal microbiota is unknown.</p>
<p>
<bold>Study Design:</bold>
Stool and groin skin swabs were collected from infants in a shared-space NICU (old NICU) and a single-family room NICU (new NICU) on the same hospital campus. Metagenomic sequencing was performed and data analyzed by CosmosID bioinformatics software package.</p>
<p>
<bold>Results:</bold>
There were no significant differences between the cohorts in gestational age, length of stay, and delivery mode; infants in the old NICU received significantly more antibiotics (
<italic>p</italic>
= 0.03). Differentially abundant antimicrobial resistance genes and virulence associated genes were found between the cohorts in stool and skin, with more differentially abundant antimicrobial resistance genes in the new NICU. The entire bacterial microbiota analyzed to the genus level significantly differed between cohorts in skin (
<italic>p</italic>
= 0.0001) but not in stool samples. There was no difference in alpha diversity between the two cohorts. DNA viruses and fungi were detected but did not differ between cohorts.</p>
<p>
<bold>Conclusion:</bold>
Differences were seen in the resistome and virulome between the two cohorts with more differentially abundant antimicrobial resistance genes in the new NICU. This highlights the influence that different NICU environments can have on the neonatal microbiota. Whether the differences were due to the new NICU being a single-family NICU or located in a newly constructed building warrants exploration. Long term health outcomes from the differences observed must be followed longitudinally.</p>
</abstract>
<kwd-group>
<kwd>microbiome</kwd>
<kwd>microbiota</kwd>
<kwd>neonatal</kwd>
<kwd>NICU</kwd>
<kwd>environment</kwd>
<kwd>resistome</kwd>
<kwd>virulome</kwd>
</kwd-group>
<counts>
<fig-count count="6"></fig-count>
<table-count count="2"></table-count>
<equation-count count="0"></equation-count>
<ref-count count="46"></ref-count>
<page-count count="13"></page-count>
<word-count count="0"></word-count>
</counts>
</article-meta>
</front>
<body>
<sec>
<title>Introduction</title>
<p>The human intestinal microbiota undergoes rapid dynamic changes in the first few months to years of life and these changes are hypothesized to shape future health (
<xref rid="B46" ref-type="bibr">Yatsunenko et al., 2012</xref>
). Dysbiosis of the intestinal microbiota has been associated with a wide range of diseases in humans, from gastrointestinal illnesses (
<xref rid="B13" ref-type="bibr">Frank et al., 2007</xref>
;
<xref rid="B28" ref-type="bibr">Manichanh et al., 2012</xref>
;
<xref rid="B5" ref-type="bibr">Collins, 2014</xref>
) to metabolic (
<xref rid="B42" ref-type="bibr">Tilg and Kaser, 2011</xref>
), atopic (
<xref rid="B14" ref-type="bibr">Fujimura et al., 2014</xref>
;
<xref rid="B45" ref-type="bibr">West et al., 2015</xref>
), and even neurodevelopmental conditions (
<xref rid="B20" ref-type="bibr">Hsiao et al., 2013</xref>
). Infants born prematurely and in the neonatal intensive care unit (NICU) are particularly vulnerable and have been shown to exhibit aberrant microbiota development, including harboring high levels of antimicrobial resistance genes (
<xref rid="B7" ref-type="bibr">Costello et al., 2013</xref>
;
<xref rid="B25" ref-type="bibr">La Rosa et al., 2014</xref>
;
<xref rid="B17" ref-type="bibr">Gibson et al., 2016</xref>
;
<xref rid="B15" ref-type="bibr">Gasparrini et al., 2016</xref>
). Moreover premature infants are at risk of developing conditions associated with microbiota dysbiosis, both in the NICU, such as life threatening necrotizing enterocolitis (
<xref rid="B34" ref-type="bibr">Pammi et al., 2017a</xref>
), and later in life (
<xref rid="B2" ref-type="bibr">Boyle et al., 2012</xref>
). In addition, it is also recognized that the human skin microbiome undergoes critical maturation in infancy (
<xref rid="B4" ref-type="bibr">Capone et al., 2011</xref>
) and can be influenced by prematurity (
<xref rid="B35" ref-type="bibr">Pammi et al., 2017b</xref>
). Aberrant development of the skin microbiome has the potential to allow pathogen colonization and has also been associated with the development of atopic dermatitis (
<xref rid="B22" ref-type="bibr">Kennedy et al., 2017</xref>
).</p>
<p>It is known that the environment influences the human microbiota with many studies showing geographical differences in child microbiota development (
<xref rid="B11" ref-type="bibr">Fallani et al., 2010</xref>
;
<xref rid="B10" ref-type="bibr">Echarri et al., 2011</xref>
;
<xref rid="B46" ref-type="bibr">Yatsunenko et al., 2012</xref>
). It has been demonstrated that microbes of the NICU resemble those found in the gut of premature infants showing the impact that this unique environment can have on microbiota development (
<xref rid="B3" ref-type="bibr">Brooks et al., 2014</xref>
). Moreover bacterial diversity from the environment can differ between different NICUs even located within a close geographical distance (
<xref rid="B19" ref-type="bibr">Hewitt et al., 2013</xref>
).</p>
<p>There is a growing demand to care for premature infants in a single-family, private room NICU rather than a traditional shared-space, open bay NICU, with some evidence showing decreased nosocomial infections, shorter length of stay, and lower cost of care, especially when nosocomial infections were considered (
<xref rid="B33" ref-type="bibr">Ortenstrand et al., 2010</xref>
;
<xref rid="B9" ref-type="bibr">Domanico et al., 2011</xref>
;
<xref rid="B40" ref-type="bibr">Stevens et al., 2014</xref>
;
<xref rid="B37" ref-type="bibr">Sadatsafavi et al., 2017</xref>
). It is known that the NICU environment can significantly influence the gut microbiota of premature infants. However, the effect of a shared-space NICU versus a single-family room NICU on the infant microbiota and incidence of antimicrobial resistance genes is unknown. The aim of this pilot study was to explore the composition, diversity and differences, if any, in the gut and skin microbiome, community resistome, and virulome among infants dwelling in a single-family room NICU versus a shared-space NICU.</p>
</sec>
<sec sec-type="materials|methods" id="s1">
<title>Materials and Methods</title>
<sec>
<title>Study Participants</title>
<p>Subjects were drawn from a larger cohort in an ongoing study entitled “The neonatal intestinal microbiome: impact on infant and early childhood health and disease” within the Inova Health System, Inova Fairfax Hospital, Falls Church, Virginia (IRB approval #15-1945). Neonates with an anticipated length of stay within the NICU of over 5 days were recruited within 3 days of life. Detailed maternal, pregnancy and delivery data were collected. While in the NICU infants had stool collected twice a week and frozen at -80°C within 12 h. Skin swabs were collected every 2 weeks using an E-Swab (Coplan, Murrieta, CA, United States) moistened with sterile saline gently rolled about 10 times in the groin area in the inguinal region. Swabs were frozen at -80°C within 12 h of collection. Detailed data regarding feeding, medications and health status were collected while the infants were in the NICU and when they were discharged, a health and disease survey and stool sample was collected every 3–6 months. The overall aim of the study was to identify microbial disruption indices prior to disease development.</p>
<p>During the course of this study the level IV Fairfax Neonatal Associates NICU at the Inova Fairfax Hospital moved from a shared-space open bay NICU (old NICU) into a single-family private room NICU in a newly constructed building that had not been previously occupied (new NICU). Subjects were selected from the cohort who had their entire NICU stay exclusively in the old NICU or the new NICU (those who spent time in both environments were excluded), had stool and skin samples available and were without any major congenital anomalies.</p>
</sec>
<sec>
<title>Samples and DNA Extraction</title>
<p>Stool samples collected from subjects at 2 weeks of life and at the time of their discharge from the NICU were selected; the two time points were chosen to investigate whether microbiota differences between the two NICU environments developed over time or were sustained over time. Groin skin swabs taken from these subjects at 2 weeks of age were also included in the analysis. The 2 week time point was chosen as the earliest time point for both the stool and skin swab because by this time, if an infant in the study had antibiotics they had already received them and all infants in the study had started to receive some enteral feeds.</p>
<p>Environmental swabs were collected from both NICUs in areas where the study subjects most often spent their hospitalization and in high use areas. Swabs were collected in a similar manner as the skin swabs. Each swab was wet with sterile saline and rolled over the sample site ten times. Two control samples of methicillin-resistant
<italic>Staphylococcus aureus</italic>
and
<italic>Escherichia coli</italic>
were also included in the analysis.</p>
<p>Each sample underwent the following preparation prior to extraction. Samples stored at -80°C were removed from storage 1 to 2 h before DNA extraction and thawed on ice. Each sample was suspended in ASL buffer (Qiagen, Valencia, CA, United States) if stool or ATL buffer if a swab (
<xref rid="B44" ref-type="bibr">Wang et al., 2008</xref>
;
<xref rid="B23" ref-type="bibr">Khelaifia et al., 2013</xref>
;
<xref rid="B12" ref-type="bibr">Fan et al., 2014</xref>
). Samples were transferred into mechanical lysis matrix tubes (MP Biomedical, Santa Ana, CA, United States). All samples were homogenized for 10 min on an oscillating vortexer (Mo Bio, Carlsbad, CA, United States) at maximum speed and placed briefly in a flash spinner to remove excess liquid from the cap (
<xref rid="B44" ref-type="bibr">Wang et al., 2008</xref>
;
<xref rid="B8" ref-type="bibr">de Boer et al., 2010</xref>
;
<xref rid="B39" ref-type="bibr">Salonen et al., 2010</xref>
;
<xref rid="B23" ref-type="bibr">Khelaifia et al., 2013</xref>
;
<xref rid="B12" ref-type="bibr">Fan et al., 2014</xref>
). Twenty five microliters of lysozyme was added at 20 mg/mL to the sample tubes and inverted ten times to mix (
<xref rid="B44" ref-type="bibr">Wang et al., 2008</xref>
). Samples were placed on a rotating heat block at 95°C for 5 min at 2000 rpm and cooled on ice for 2–5 min. Samples were centrifuged at 20,000 ×
<italic>g</italic>
for 2 min and the supernatant was removed and placed in a new 2 mL Eppendorf tube without disturbing the pellet and matrix lysis tube beads (
<xref rid="B44" ref-type="bibr">Wang et al., 2008</xref>
;
<xref rid="B23" ref-type="bibr">Khelaifia et al., 2013</xref>
;
<xref rid="B31" ref-type="bibr">Moles et al., 2013</xref>
). Then one Inhibit X tablet (Qiagen, Valencia, CA, United States) was added to each tube and vortexed until the tablet completely dissolved and incubated at room temperature for 3 min (
<xref rid="B44" ref-type="bibr">Wang et al., 2008</xref>
). Samples were centrifuged at 20,000 ×
<italic>g</italic>
for 2 min; supernatant was removed and put into a clean 1.5 mL Eppendorf tube, and centrifuged again at 20,000 ×
<italic>g</italic>
for 3 min (
<xref rid="B44" ref-type="bibr">Wang et al., 2008</xref>
). To finish extraction on the EZ1 (Qiagen, Valencia CA, United States), 400 uL were placed into an extraction tube and loaded onto the machine using the EZ1 DSP kit with the viral extraction protocol card. Each sample was cleaned and concentrated using the NucleoSpin gDNA Clean-up XS kit (MACHEREY-NAGEL GmbH & Co. KG).</p>
</sec>
<sec>
<title>Sequencing and Metagenomic Analyses</title>
<p>DNA samples were normalized in 50 μL of nuclease-free water using 0.0–0.29 ug of input materials on the Biomek FX liquid handler. For each sample, an input of 0.5 ng was used in the tagmentation reaction, followed by 13 cycles of PCR amplification using Nextera i7 and i5 index primers and 2× Kapa master mix per the modified Nextera XT protocol. The PCR products were purified using 1.0× speed beads and eluted in 15 ul of nuclease-free water. The final libraries were then quantitated using the picogreen fluorometric assay (100× final dilution) and the concentrations were in the range of 0.1–4.0 ng/ul. The libraries were pooled based on their concentrations as determined by picogreen and loaded onto a high sensitivity chip run on the Caliper LabChipGX; the base pair size reported was in the range of 301–680 bp. Libraries were sequenced using Illumina HiSeq v3 chemistry for 100 bp single end reads with the aim to generate 40 M reads per sample.</p>
<p>Unassembled metagenomic sequencing reads were directly analyzed using the CosmosID bioinformatics software package (CosmosID Inc., Rockville, MD, United States) as described previously (
<xref rid="B18" ref-type="bibr">Hasan et al., 2014</xref>
;
<xref rid="B27" ref-type="bibr">Lax et al., 2014</xref>
;
<xref rid="B36" ref-type="bibr">Ponnusamy et al., 2016</xref>
) to achieve microbial identification to the species, subspecies, and/or strain level and quantification of organism’s relative abundance. CosmosID is a microbial genomics platform focused on rapid characterization of microorganisms, pathogens and anti-microbial resistance for infectious disease identification, food safety inspections, pharmaceutical discovery, public health surveillance and microbiome analysis. CosmosID bioinformatics utilizes high performance data mining algorithms and highly curated dynamic comparator databases (GenBook
<sup>®</sup>
) that are readily accessible by cloud interface. The curated databases provide extremely fine resolution in identification, discrimination of pathogens from ‘near neighbors’, and accurate measurement of relative abundances. CosmosID utilizes a high performance data-mining K-mer based algorithm that rapidly disambiguates hundreds of millions of short reads of a metagenomic sample into the discrete microorganisms engendering the particular sequences. While the tools are flexible and can be used to compare whole genomes, the principal software pipeline has been optimized for processing unmapped and unaligned raw sequence reads of lengths less than 100 basepairs. The pipeline has two separable comparators. The first consists of a pre-computation phase and a per-sample computation. The input to the pre-computation phase is a reference microbial database, and its output is a whole genome phylogeny tree, together with sets of fixed length k-mer fingerprints (biomarkers) that are uniquely identified with distinct nodes of the tree. The second per-sample, computational phase searches the hundreds of millions of short sequence reads against the fingerprint sets in minutes. The resulting statistics are analyzed to give fine-grain composition and relative abundance estimates at all nodes of the tree. The second comparator uses edit distance-scoring techniques to compare a target sample with a reference set. The algorithm provides similar functionality to BLAST but sacrifices some recall precision for a one or two order of magnitude processing gain. Overall classification precision is maintained through aggregation statistics. This second comparator may be used independently of the first. However, enhanced discriminatory power is achieved by running the comparators in sequence. The first comparator finds reads in which there is an exact match with an n-mer uniquely identified with a set of reference strains; the second comparator then statistically scores the entire read against the reference to verify that the read is indeed uniquely identified with that set. Similarly, the community resistome and virulome, the collection of antibiotic resistance and virulence genes respectively in the microbiome, were also profiled by querying unassembled sequence reads against CosmosID curated antibiotic resistance and virulence gene databases.</p>
</sec>
<sec>
<title>Comparative Statistical Analysis</title>
<p>Demographic and clinical features were compared between the two NICU cohorts using Chi-squared or Fischer’s exact test, as appropriate, for categorical variables and an unpaired two tailed
<italic>T</italic>
-test for continuous variables. Analyses of the sequencing data included generation of heatmaps based on the relative abundance of each microorganism (%) in each sample using the NMF R software package (
<xref rid="B16" ref-type="bibr">Gaujoux and Seoighe, 2010</xref>
). Likelihood ratio testing was performed using a parameterization of the Dirichlet-Multinomial distribution developed for comparisons of whole genome shotgun metagenomic datasets (
<xref rid="B24" ref-type="bibr">La Rosa et al., 2012</xref>
) using the data subsampled to 10 million reads to avoid any statistical bias due to different sample sizes. Similarity index calculations were performed as described (
<xref rid="B41" ref-type="bibr">Tarkkanen et al., 2009</xref>
) using the Pearson correlation and boxplots were computed using the ggplot2 R library (
<xref rid="B30" ref-type="bibr">McGill et al., 1978</xref>
). Principal coordinate analysis (PCoA) was performed using the Bray-Curtis distance measure and clustered using the Partitioning Around Medoids (PAM) algorithm (
<xref rid="B21" ref-type="bibr">Kaufman and Rousseeuw, 1987</xref>
). Resistome analysis was performed by identification of antibiotic-resistance genes based on percentage of gene coverage for each gene as a function of the gene-specific read frequency in each sample. Statistical analyses were performed using a one-tailed Student’s
<italic>T</italic>
-test.</p>
</sec>
</sec>
<sec>
<title>Results</title>
<sec>
<title>Demographics and Clinical Factors</title>
<p>A total of 32 infants were included in this study, 14 from the old NICU and 18 from the new NICU.
<bold>Table
<xref rid="T1" ref-type="table">1</xref>
</bold>
shows demographic and key clinical features for the two groups. There were no significant differences between the two cohorts in gestational age, length of stay or delivery mode. There was a significantly greater amount of antibiotic use during NICU stay in the old NICU, compared with the new NICU (12/14 infants in old NICU vs. 8 /18 infants in new NICU,
<italic>p</italic>
= 0.03). Analysis of the specific classes of antibiotics used showed more 3rd generation cephalosporin use in the old NICU compared with the new NICU (4/14 infants in old NICU vs. 0/18 infants in new NICU,
<italic>p</italic>
= 0.03). No difference was detected between maternal antibiotic use in pregnancy between the two cohorts nor was there any difference between the number of infants who received total parenteral nutrition (TPN) or some maternal or donor breast milk. However, more infants in the old NICU received exclusive maternal or donor breast milk (after TPN use if needed) compared with the new NICU (11/14 infants in old NICU vs. 7/18 infants in new NICU,
<italic>p</italic>
= 0.04).</p>
<table-wrap id="T1" position="float">
<label>Table 1</label>
<caption>
<p>Comparison of demographics and clinical factors between the Old and New NICU.</p>
</caption>
<table frame="hsides" rules="groups" cellspacing="5" cellpadding="5">
<thead>
<tr>
<th valign="top" align="left" rowspan="1" colspan="1"></th>
<th valign="top" align="center" rowspan="1" colspan="1">Old NICU</th>
<th valign="top" align="center" rowspan="1" colspan="1">New NICU</th>
<th valign="top" align="center" rowspan="1" colspan="1">
<italic>p</italic>
-value</th>
</tr>
</thead>
<tbody>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1">Number of subjects</td>
<td valign="top" align="center" rowspan="1" colspan="1">14</td>
<td valign="top" align="center" rowspan="1" colspan="1">18</td>
<td valign="top" align="center" rowspan="1" colspan="1"></td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1">Mean gestational age in weeks</td>
<td valign="top" align="center" rowspan="1" colspan="1">31.4</td>
<td valign="top" align="center" rowspan="1" colspan="1">33.2</td>
<td valign="top" align="center" rowspan="1" colspan="1">0.16</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1">Average length of stay in days</td>
<td valign="top" align="center" rowspan="1" colspan="1">33.5</td>
<td valign="top" align="center" rowspan="1" colspan="1">33.2</td>
<td valign="top" align="center" rowspan="1" colspan="1">0.52</td>
</tr>
<tr>
<td valign="top" align="left" colspan="4" rowspan="1">
<bold>Mode of delivery</bold>
</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1">Vaginal delivery</td>
<td valign="top" align="center" rowspan="1" colspan="1">5</td>
<td valign="top" align="center" rowspan="1" colspan="1">1</td>
<td valign="top" align="center" rowspan="1" colspan="1">0.06</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1">Cesarean Section</td>
<td valign="top" align="center" rowspan="1" colspan="1">19</td>
<td valign="top" align="center" rowspan="1" colspan="1">17</td>
<td valign="top" align="center" rowspan="1" colspan="1"></td>
</tr>
<tr>
<td valign="top" align="left" colspan="4" rowspan="1">
<bold>Infant antibiotic use ever</bold>
</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1">Yes</td>
<td valign="top" align="center" rowspan="1" colspan="1">12</td>
<td valign="top" align="center" rowspan="1" colspan="1">8</td>
<td valign="top" align="center" rowspan="1" colspan="1">
<bold>0.03</bold>
</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1">No</td>
<td valign="top" align="center" rowspan="1" colspan="1">2</td>
<td valign="top" align="center" rowspan="1" colspan="1">10</td>
<td valign="top" align="center" rowspan="1" colspan="1"></td>
</tr>
<tr>
<td valign="top" align="left" colspan="4" rowspan="1">
<bold>Infant type of antibiotic use</bold>
</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1">Ampicillin</td>
<td valign="top" align="center" rowspan="1" colspan="1">10</td>
<td valign="top" align="center" rowspan="1" colspan="1">8</td>
<td valign="top" align="center" rowspan="1" colspan="1">0.16</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1">Gentamicin</td>
<td valign="top" align="center" rowspan="1" colspan="1">10</td>
<td valign="top" align="center" rowspan="1" colspan="1">8</td>
<td valign="top" align="center" rowspan="1" colspan="1">0.16</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1">1
<sup>st</sup>
generation cephalosporin</td>
<td valign="top" align="center" rowspan="1" colspan="1">1</td>
<td valign="top" align="center" rowspan="1" colspan="1">1</td>
<td valign="top" align="center" rowspan="1" colspan="1">1.00</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1">2
<sup>nd</sup>
generation cephalosporin</td>
<td valign="top" align="center" rowspan="1" colspan="1">1</td>
<td valign="top" align="center" rowspan="1" colspan="1">0</td>
<td valign="top" align="center" rowspan="1" colspan="1">0.44</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1">3
<sup>rd</sup>
generation cephalosporin</td>
<td valign="top" align="center" rowspan="1" colspan="1">4</td>
<td valign="top" align="center" rowspan="1" colspan="1">0</td>
<td valign="top" align="center" rowspan="1" colspan="1">
<bold>0.03</bold>
</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1">Vancomycin</td>
<td valign="top" align="center" rowspan="1" colspan="1">0</td>
<td valign="top" align="center" rowspan="1" colspan="1">1</td>
<td valign="top" align="center" rowspan="1" colspan="1">1.00</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1">Piperacillin/tazobactam</td>
<td valign="top" align="center" rowspan="1" colspan="1">0</td>
<td valign="top" align="center" rowspan="1" colspan="1">1</td>
<td valign="top" align="center" rowspan="1" colspan="1">1.00</td>
</tr>
<tr>
<td valign="top" align="left" colspan="4" rowspan="1">
<bold>Maternal use of antibiotics during pregnancy (notincluding those given at Cesarean Section)</bold>
</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1">Ever (may include more than 1 course)</td>
<td valign="top" align="center" rowspan="1" colspan="1">1</td>
<td valign="top" align="center" rowspan="1" colspan="1">3</td>
<td valign="top" align="center" rowspan="1" colspan="1">0.61</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1">Ampicillin</td>
<td valign="top" align="center" rowspan="1" colspan="1">1</td>
<td valign="top" align="center" rowspan="1" colspan="1">0</td>
<td valign="top" align="center" rowspan="1" colspan="1">0.44</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1">Azithromycin</td>
<td valign="top" align="center" rowspan="1" colspan="1">1</td>
<td valign="top" align="center" rowspan="1" colspan="1">0</td>
<td valign="top" align="center" rowspan="1" colspan="1">0.44</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1">1
<sup>st</sup>
generation cephalosporin</td>
<td valign="top" align="center" rowspan="1" colspan="1">0</td>
<td valign="top" align="center" rowspan="1" colspan="1">3</td>
<td valign="top" align="center" rowspan="1" colspan="1">0.24</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1">Nitrofurantoin</td>
<td valign="top" align="center" rowspan="1" colspan="1">0</td>
<td valign="top" align="center" rowspan="1" colspan="1">1</td>
<td valign="top" align="center" rowspan="1" colspan="1">1.00</td>
</tr>
<tr>
<td valign="top" align="left" colspan="4" rowspan="1">
<bold>Nutrition</bold>
</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1">Ever received TPN</td>
<td valign="top" align="center" rowspan="1" colspan="1">12</td>
<td valign="top" align="center" rowspan="1" colspan="1">12</td>
<td valign="top" align="center" rowspan="1" colspan="1">0.41</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1">Primarily receiving maternal or donor breast milk only (excluding fortifiers)</td>
<td valign="top" align="center" rowspan="1" colspan="1">11</td>
<td valign="top" align="center" rowspan="1" colspan="1">7</td>
<td valign="top" align="center" rowspan="1" colspan="1">
<bold>0.04</bold>
</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1">Receiving some maternal or donor breast milk</td>
<td valign="top" align="center" rowspan="1" colspan="1">11</td>
<td valign="top" align="center" rowspan="1" colspan="1">17</td>
<td valign="top" align="center" rowspan="1" colspan="1">0.30</td>
</tr>
</tbody>
</table>
<table-wrap-foot>
<attrib>
<italic>Bolded values are statistically significant.</italic>
</attrib>
</table-wrap-foot>
</table-wrap>
</sec>
<sec>
<title>Metagenomic Sequencing</title>
<p>
<bold>Table
<xref rid="T2" ref-type="table">2</xref>
</bold>
shows the number of each type of sample successfully sequenced from each NICU cohort and also lists the locations of the environmental swabs obtained. Area 1 and area 2 of the new NICU represent two areas separated geographically that the babies in this cohort most frequently stayed in. Between sample types, there was no significant difference in the amount of DNA extracted between cohorts.</p>
<table-wrap id="T2" position="float">
<label>Table 2</label>
<caption>
<p>Number of each sample type and comparison of the quantity of DNA extracted from each sample type from the Old and New NICU.</p>
</caption>
<table frame="hsides" rules="groups" cellspacing="5" cellpadding="5">
<thead>
<tr>
<th valign="top" align="left" rowspan="1" colspan="1"></th>
<th valign="top" align="center" colspan="2" rowspan="1">Old NICU (n)</th>
<th valign="top" align="center" rowspan="1" colspan="1">Mean DNA
<break></break>
extracted in ng</th>
<th valign="top" align="center" colspan="2" rowspan="1">New NICU (n)</th>
<th valign="top" align="center" rowspan="1" colspan="1">Mean DNA
<break></break>
extracted in ng</th>
<th valign="top" align="center" rowspan="1" colspan="1">
<italic>p</italic>
-value for difference in
<break></break>
DNA between 2 cohorts</th>
</tr>
</thead>
<tbody>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1">2 week stool samples</td>
<td valign="top" align="center" rowspan="1" colspan="1">9</td>
<td valign="top" align="center" colspan="2" rowspan="1">7.09</td>
<td valign="top" align="center" rowspan="1" colspan="1">13</td>
<td rowspan="1" colspan="1"></td>
<td valign="top" align="center" rowspan="1" colspan="1">3.72</td>
<td valign="top" align="center" rowspan="1" colspan="1">0.48</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1">Discharge stool samples</td>
<td valign="top" align="center" rowspan="1" colspan="1">12</td>
<td valign="top" align="center" colspan="2" rowspan="1">16.66</td>
<td valign="top" align="center" rowspan="1" colspan="1">14</td>
<td rowspan="1" colspan="1"></td>
<td valign="top" align="center" rowspan="1" colspan="1">4.90</td>
<td valign="top" align="center" rowspan="1" colspan="1">0.33</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1">Subjects with both stool samples</td>
<td valign="top" align="center" rowspan="1" colspan="1">9</td>
<td valign="top" align="center" colspan="2" rowspan="1">n/a</td>
<td valign="top" align="center" rowspan="1" colspan="1">10</td>
<td rowspan="1" colspan="1"></td>
<td valign="top" align="center" rowspan="1" colspan="1">n/a</td>
<td valign="top" align="center" rowspan="1" colspan="1">n/a</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1">Skin samples</td>
<td valign="top" align="center" rowspan="1" colspan="1">11</td>
<td valign="top" align="center" colspan="2" rowspan="1">4.46</td>
<td valign="top" align="center" rowspan="1" colspan="1">10</td>
<td rowspan="1" colspan="1"></td>
<td valign="top" align="center" rowspan="1" colspan="1">3.16</td>
<td valign="top" align="center" rowspan="1" colspan="1">0.53</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1">Environmental samples</td>
<td valign="top" align="center" rowspan="1" colspan="1">6</td>
<td valign="top" align="center" colspan="2" rowspan="1">1.26</td>
<td valign="top" align="center" rowspan="1" colspan="1">10</td>
<td rowspan="1" colspan="1"></td>
<td valign="top" align="center" rowspan="1" colspan="1">0.49</td>
<td valign="top" align="center" rowspan="1" colspan="1">0.08</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1">Location of environmental samples</td>
<td rowspan="1" colspan="1"></td>
<td valign="top" align="left" rowspan="1" colspan="1">∙ Sink</td>
<td rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td valign="top" align="left" rowspan="1" colspan="1">
<bold>Area 1</bold>
</td>
<td valign="top" align="left" rowspan="1" colspan="1"></td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td valign="top" align="left" rowspan="1" colspan="1">∙ Vitals monitor</td>
<td rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td valign="top" align="left" rowspan="1" colspan="1">∙ Sink</td>
<td valign="top" align="left" rowspan="1" colspan="1"></td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td valign="top" align="left" rowspan="1" colspan="1">∙ Nurse station</td>
<td rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td valign="top" align="left" rowspan="1" colspan="1">∙ Vitals monitor</td>
<td valign="top" align="left" rowspan="1" colspan="1"></td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td valign="top" align="left" rowspan="1" colspan="1">∙ Light switch</td>
<td rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td valign="top" align="left" rowspan="1" colspan="1">∙ Bedside cart</td>
<td valign="top" align="left" rowspan="1" colspan="1"></td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td valign="top" align="left" rowspan="1" colspan="1">∙ Foam pump</td>
<td rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td valign="top" align="left" rowspan="1" colspan="1">∙ Nurses station</td>
<td valign="top" align="left" rowspan="1" colspan="1"></td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td valign="top" align="left" rowspan="1" colspan="1">∙ Baby swing chair</td>
<td rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td valign="top" align="left" rowspan="1" colspan="1">∙ Foam pump</td>
<td valign="top" align="left" rowspan="1" colspan="1"></td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td valign="top" align="left" rowspan="1" colspan="1">
<bold>Area 2</bold>
</td>
<td valign="top" align="left" rowspan="1" colspan="1"></td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td valign="top" align="left" rowspan="1" colspan="1">∙ Sink</td>
<td valign="top" align="left" rowspan="1" colspan="1"></td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td valign="top" align="left" rowspan="1" colspan="1">∙ Vitals monitor</td>
<td valign="top" align="left" rowspan="1" colspan="1"></td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td valign="top" align="left" rowspan="1" colspan="1">∙ Bedside cart</td>
<td valign="top" align="left" rowspan="1" colspan="1"></td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td valign="top" align="left" rowspan="1" colspan="1">∙ Nurses station</td>
<td valign="top" align="left" rowspan="1" colspan="1"></td>
</tr>
<tr>
<td valign="top" align="left" rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td rowspan="1" colspan="1"></td>
<td valign="top" align="left" rowspan="1" colspan="1">∙ Foam pump</td>
<td valign="top" align="left" rowspan="1" colspan="1"></td>
</tr>
</tbody>
</table>
</table-wrap>
<p>Metagenomic sequencing of DNA extracted for skin, stool and environment swabs generated 22–67 million reads per sample with an average of 46 million reads per sample. Sequence data were deposited in to NCBI Bioproject under accession number
<ext-link ext-link-type="DDBJ/EMBL/GenBank" xlink:href="PRJNA417283">PRJNA417283</ext-link>
.</p>
</sec>
<sec>
<title>Species Alpha Diversity</title>
<p>There was no significant difference in species alpha diversity using the Chao 1 index, in any of the four samples types between the two NICU cohorts (
<bold>Figure
<xref ref-type="fig" rid="F1">1</xref>
</bold>
). However, noticeable variation was observed within the sample types, i.e., environment and groin swabs demonstrated greater alpha diversity than that of 2 week and discharge stool samples.</p>
<fig id="F1" position="float">
<label>FIGURE 1</label>
<caption>
<p>Alpha diversity using the Chao 1 index of each sample type (2 week stool, discharge stool, environmental swabs, and groin skin swabs) in the old NICU and the new NICU. There was no significant difference in any of the four samples types between the two NICU cohorts.</p>
</caption>
<graphic xlink:href="fmicb-09-01361-g001"></graphic>
</fig>
</sec>
<sec>
<title>Comparison of the Entire Bacterial Microbiota</title>
<p>Using the likelihood ratio test, comparison of the entire bacterial community at the genus level showed no difference between infants from the old and new NICU in 2 week and discharge stool samples (
<italic>p</italic>
= 1.00), but did show a significant difference between skin swab (
<italic>p</italic>
= 0.0001) and environmental swab samples (
<italic>p</italic>
= 0.0003) for the two cohorts (
<bold>Figure
<xref ref-type="fig" rid="F2">2</xref>
</bold>
). There was no significant difference between 2 week and discharge stool samples from the old NICU but there was a significant difference between 2 week and discharge stool samples from the new NICU (
<italic>p</italic>
= 0.0006).</p>
<fig id="F2" position="float">
<label>FIGURE 2</label>
<caption>
<p>The bacterial microbiome at the taxonomic level of genus in each sample type in the old NICU and the new NICU samples. Using the likelihood ratio test, there was no difference between the old and new NICU in 2 week and discharge stool samples (
<italic>p</italic>
= 1.00), but there was a significant difference between groin skin swab (
<italic>p</italic>
= 0.0001) and environmental swab samples (
<italic>p</italic>
= 0.0003) between the two cohorts.</p>
</caption>
<graphic xlink:href="fmicb-09-01361-g002"></graphic>
</fig>
</sec>
<sec>
<title>Specific Taxa Comparison</title>
<p>Heat maps showing relative abundance of genera represented in the 2-week and discharge stool samples are provided in
<bold>Supplementary Figure
<xref ref-type="supplementary-material" rid="SM1A">S1A</xref>
</bold>
, stratified by if the infant was primarily receiving breast milk at the time of the sample collection. Specific taxa of interest were noted, with no significant differences observed between
<italic>Bifidobacterium, Lactobacillus, Enterobacteriaceae, Staphylococcaceae, and Ureaplasma</italic>
in both 2 week and discharge stool samples for the two NICU cohorts or by breast milk status. Heat maps showing relative abundance of genera in skin samples and environmental samples between the two cohorts are provided in
<bold>Supplementary Figures
<xref ref-type="supplementary-material" rid="SM1B">S1B</xref>
,
<xref ref-type="supplementary-material" rid="SM1C">C</xref>
</bold>
, respectively. The following specific taxa of interest were analyzed for skin samples, with no significant difference between the two cohorts:
<italic>Proteobacteria, Firmicutes, Actinobacteria, Staphylococcus, Staphylococcus aureus</italic>
. The following specific taxa of interest were examined in the environmental samples and no significant difference was observed between the two cohorts:
<italic>Streptococcus, Staphylococcus, Neisseria, Enterobacteriaceae, Klebsiella, Bacteroides fragilis, Escherichia coli</italic>
.</p>
<p>
<bold>Supplementary Figure
<xref ref-type="supplementary-material" rid="SM2">S2</xref>
</bold>
shows a PCoA biplot of bacterial content at the taxonomic level of class for 2 week and discharge stool samples, comparing old and new NICU after removal of outliers. Interestingly outliers from the old and new NICU, shown in the bottom left of
<bold>Supplementary Figure
<xref ref-type="supplementary-material" rid="SM2">S2</xref>
</bold>
reveal clustering on different sides of the plot. Arrows point in the direction of highest correlation between taxa and sample clusters and are colored by phyla.</p>
</sec>
<sec>
<title>Antimicrobial Resistance Genes</title>
<p>Antimicrobial resistance genes were compared between sample types of the two cohorts.
<bold>Figures
<xref ref-type="fig" rid="F3">3A</xref>
<xref ref-type="fig" rid="F3">D</xref>
</bold>
show antibiotic resistance genes with over a two log difference between old and new NICU for the 2 week stool, discharge stool, skin swabs, and environmental swabs, respectively. More antibiotic resistance genes were differentially abundant in samples collected from the new NICU compared to the old NICU for all sample types. Of note, in stool samples, both 2 week and discharge, and skin swabs, beta lactam resistance genes were notably more differentially abundant in the new NICU samples than the old NICU. Due to the difference in antibiotic use seen between the 2 cohorts (higher use in old NICU), differentially abundant antimicrobial resistance genes were compared between only those who received antibiotics in the old and new NICU, and between those who did not receive antibiotics in the old and new NICU (
<bold>Supplementary Figures
<xref ref-type="supplementary-material" rid="SM3A">S3A</xref>
,
<xref ref-type="supplementary-material" rid="SM3B">B</xref>
</bold>
, respectively). In those who received antibiotics, more differentially abundant genes were seen in the new NICU compared with the old NICU in the 2 week stool sample only. Of note, in those who received antibiotics, different differentially abundant genes were identified compared with the cohort as a whole, with tetracycline resistance genes more abundant in the new NICU. In comparing those without antibiotic exposure, differentially abundant antimicrobial resistance genes were only seen in skin swabs, with more genes in the new NICU. Due to the difference seen in infants primarily receiving breast milk (higher in the old NICU), differentially abundant antimicrobial resistance genes were compared between only those who primarily received breast milk in the old and new NICU, and between those who did not primarily receive breast milk in the old and new NICU (
<bold>Supplementary Figures
<xref ref-type="supplementary-material" rid="SM4A">S4A</xref>
,
<xref ref-type="supplementary-material" rid="SM4B">B</xref>
</bold>
, respectively). In those who primarily received breast milk, more differentially abundant antibiotic resistance genes were still seen in the new NICU in the 2 week stool and skin swabs samples with a notable prominence of tetracycline and beta lactam resistance genes. In those who did not primarily receive breast milk, more differentially abundant genes were seen in the new NICU in the 2 week stool and discharge stool samples, once again with a notable difference in beta lactam resistance genes. However, in skin swabs more differentially abundant genes were seen in the old NICU in those who did not primarily receive breast milk. No individual from either cohort developed clinically detectable infection caused by an antibiotic resistant organism during their NICU stay.</p>
<fig id="F3" position="float">
<label>FIGURE 3</label>
<caption>
<p>Antimicrobial resistance genes showing more than two-fold log change in prevalence in samples collected from the new NICU compared to the old NICU samples. Antibiotic resistance genes were more abundant in the new NICU, compared to the old NICU, in all sample types.
<bold>(A)</bold>
2 week stool,
<bold>(B)</bold>
discharge stool,
<bold>(C)</bold>
skin swab, and
<bold>(D)</bold>
environmental swab.</p>
</caption>
<graphic xlink:href="fmicb-09-01361-g003"></graphic>
</fig>
</sec>
<sec>
<title>Virulence Associated Genes</title>
<p>Virulence related genes were compared between samples types between the two cohorts.
<bold>Figures
<xref ref-type="fig" rid="F4">4A</xref>
<xref ref-type="fig" rid="F4">D</xref>
</bold>
show virulence associated genes with more than a log two difference between old and new NICU in 2 week stool, discharge stool, skin swabs, and environmental swabs, respectively. Differentially abundant virulence related genes between the two cohorts were found in each sample type. Discharge stool samples demonstrated a difference in virulence related genes typically associated with
<italic>Escherichia coli</italic>
in the new NICU and
<italic>Bacteroides fragilis</italic>
and
<italic>Enterobacter</italic>
associated virulence genes in the old NICU. In skin swabs a bigger difference was observed among
<italic>Bacteroides fragilis and Bacteroides thetaiotaomicron</italic>
associated virulence genes in the old NICU and
<italic>Enterobacter, Enterococcus faecalis</italic>
and
<italic>Clostridium perfringens</italic>
associated virulence genes in the new NICU. Environmental samples revealed a difference in
<italic>Staphylococcus aureus</italic>
related virulence factor coding genes in samples from the new NICU. However, it is important to note that as virulence genes often undergo horizontal gene transfer, it is possible that any other microbial community members and not those typically known to harbor those genes, may have been carrying these genes.</p>
<fig id="F4" position="float">
<label>FIGURE 4</label>
<caption>
<p>Virulence associated genes with over a log two fold change in prevalence in the new NICU compared with the old NICU samples. Differentially abundant virulence associated genes were detected in all sample types between the two NICU cohorts.
<bold>(A)</bold>
2 week stool,
<bold>(B)</bold>
discharge stool,
<bold>(C)</bold>
skin swab, and
<bold>(D)</bold>
environmental swab.</p>
</caption>
<graphic xlink:href="fmicb-09-01361-g004"></graphic>
</fig>
</sec>
<sec>
<title>Viruses</title>
<p>DNA viruses were detected in all sample types in both cohorts, as shown in
<bold>Figure
<xref ref-type="fig" rid="F5">5</xref>
</bold>
, and consisted primarily of phages. No significant differences in 2 week stool, discharge stool and skin samples were noted between the two NICU cohorts with respect to potential human pathogenic viruses (including herpesvirus, papillomavirus, adenovirus, merckel cell virus, corona virus and respiratory syncytial virus). The environmental samples however revealed polyomaviruses were more frequently detected in samples from the old NICU compared with the new NICU (
<italic>p</italic>
= 0.017). No subject developed any clinically detectable viral infections during their stay in the NICU.</p>
<fig id="F5" position="float">
<label>FIGURE 5</label>
<caption>
<p>DNA viruses by sample type. DNA viruses were detected in all sample types in both cohorts and were predominantly phages.</p>
</caption>
<graphic xlink:href="fmicb-09-01361-g005"></graphic>
</fig>
</sec>
<sec>
<title>Fungi and Parasites</title>
<p>
<bold>Figure
<xref ref-type="fig" rid="F6">6</xref>
</bold>
shows a tree map of fungi detected in samples analyzed in this study. Fungi were not present in all samples, but were more frequently detected in stool samples. A parasite,
<italic>Acanthamoeba polyphaga</italic>
, was detected in a skin swab sample from a subject from the old NICU.</p>
<fig id="F6" position="float">
<label>FIGURE 6</label>
<caption>
<p>A tree map of fungi detected in samples collected in this study. Fungi were not detected in all samples, but were more common in stool samples.</p>
</caption>
<graphic xlink:href="fmicb-09-01361-g006"></graphic>
</fig>
</sec>
<sec>
<title>Controls</title>
<p>Sequencing of the controls,
<italic>Staphylococcus aureus</italic>
and
<italic>Escherichia coli</italic>
, provided reference for the analyses as a test for contamination and quality of the analyses.</p>
</sec>
</sec>
<sec>
<title>Discussion</title>
<p>This pilot study is the first to compare microbiome differences between infants in an open bay shared-space NICU (old NICU) and the transition to a new hospital building with a single-family room NICU environment (new NICU), both on the same hospital campus.</p>
<p>Notably, differentially abundant antibiotic resistance genes were observed in all sample types (stool, skin, and environment) between both cohorts, with more abundant antibiotic resistance genes detected in samples collected from the new NICU. The hypothesis was that the new single-family room NICU would have fewer antibiotic resistance genes detected in the microbiota of infants because single-family room NICUs have been shown to have decreased rates of nosocomial sepsis (
<xref rid="B9" ref-type="bibr">Domanico et al., 2011</xref>
). In addition, it is assumed that there is patient to patient transfer of microbiota, including those microorganisms with antibiotic resistance potential, via hand carriage of health workers. Open bay NICUs are hypothesized to lead to decreased hand washing frequency or less efficiency between patients whereas private rooms have readily accessible hand washing stations in each room, providing more opportunity for hand washing by healthcare workers (
<xref rid="B38" ref-type="bibr">Saiman, 2002</xref>
;
<xref rid="B43" ref-type="bibr">Walsh et al., 2006</xref>
). The results were therefore surprising, finding more abundant antibiotic resistance genes in samples collected from the new NICU, especially as there was significantly less antibiotic use in the new NICU compared with the old, with antibiotic use being a known risk factor (
<xref rid="B15" ref-type="bibr">Gasparrini et al., 2016</xref>
;
<xref rid="B17" ref-type="bibr">Gibson et al., 2016</xref>
). Specifically, cephalosporin use was less in the new NICU, even though beta lactam resistance genes were relatively more abundant in stool and skin samples in the new NICU. Even when antimicrobial resistance genes were compared in only those who had received antibiotics, differentially abundant genes were found between the two cohorts although the specific genes did differ. A possible explanation for the differentially abundant antibiotic resistance genes between samples from the two cohorts is that the resistome in this study may reflect the new NICU being located in a newly constructed building, that was previously unoccupied. A recent study by
<xref rid="B26" ref-type="bibr">Lax et al. (2017)</xref>
examined microbiota colonization and succession in a newly opened hospital, using both environmental and skin swabs. Bacterial communities on the skin of patients and from room surfaces became increasingly similar over the course of a patient’s stay and alpha and beta diversity of skin swabs was found to be only weakly associated with antibiotic usage. Moreover,
<xref rid="B26" ref-type="bibr">Lax et al. (2017)</xref>
showed in samples that underwent metagenomic sequencing, antibiotic resistance genes were more prevalent on surfaces of the room than on skin of the patient. The combined results do indicate that the microbiota of a patient is susceptible to influence of the environmental microbiota in a building. This factor may be more influential in the NICU sample comparisons of this study as newborns begin life with a very “naïve” immature microbiota and may be more vulnerable to colonization from external sources. Antimicrobial resistance genes have a survival advantage and may be more prevalent when there is less competition from lack of established bacterial communities in a new building. It is possible that over time the new NICU “matures” in terms of microbiota colonization, effecting favorable change in the community resistome. Another possible explanation of the finding is that neonates in the new NICU are potentially exposed to fewer caregivers and if a specific caregiver carries more of these genes they may be more likely to colonize the infant. However, contradicting this, it was found that antimicrobial resistance genes in the new NICU did not cluster in certain individuals and were found in all sample types across infants. Lastly, it could be hypothesized that differences in feeding and nutrition between the 2 cohorts may have contributed to the difference in antimicrobial resistance genes seen. However, more infants primarily received breast milk in the old NICU, which is thought to be a protective factor (
<xref rid="B29" ref-type="bibr">Marks et al., 2013</xref>
), yet more differentially abundant antimicrobial genes were seen in the new NICU. Indeed, even when samples from only infants who primarily received breast milk were examined overall more differentially abundant antimicrobial genes were still seen in the new NICU.</p>
<p>Differentially abundant virulence related genes were also found in all sample types between the two NICU cohorts. Little information has been published concerning the virulome in the NICU, except for specific microorganisms. Thus this study provides valuable new information. The specific genes detected in samples collected from the new NICU may be more reflective of a newly constructed building, without competitive microbiota or colonization, rather than a single-family NICU. It is important to note that no infant from either cohort developed any clinically detectable infections caused by antibiotic resistant organisms or organisms associated with the detected virulence factors during their NICU stay. It is imperative to repeat this study with neonates who have been in the new NICU for a longer time after opening to determine whether differences observed in our study were more reflective of a new building or of a single-family room environment. Moreover, it is key to determine whether these observed differences persist into childhood, with long term health outcomes. A recent study indicated that the high levels of antibiotic resistance in the neonatal microbiota of infants found in the NICU may normalize at 2 years of age (
<xref rid="B32" ref-type="bibr">Moles et al., 2015</xref>
). This interesting observation will be investigated for the cohorts of this study in our longitudinal investigation.</p>
<p>No differences were observed in alpha diversity between the two cohorts but it is notable that environmental samples in the new NICU were as diverse as those in the old NICU, given the limited time the new building was operative and able to be to colonized. Lax et al. observed that, after hospital opening, alpha diversity increased in samples collected from the surfaces of the nurses’ station, which had common human skin contact, but not for floor samples (
<xref rid="B21" ref-type="bibr">Kaufman and Rousseeuw, 1987</xref>
). In our study, overall comparison of the bacterial microbiota revealed no differences between the two cohorts, with respect to stool samples. Individual variability and small sample size may be factors, but differences were observed in both patient skin and environmental samples. It will be important to monitor ecological succession of new NICU as it matures over time and determine whether these differences persist and exert any long-term outcomes for neonates. Although no differences were detected in DNA viruses, fungi, and parasites between the two patient cohorts, this comprehensive exploration emphasizes the power of such analysis for detection of potential pathogens and characterization of the virulome and resistome. Follow up studies should employ metatranscriptomics to also address if differences in RNA viruses are detected in infants from different NICU environments.</p>
<p>Limitations of this pilot study include a relatively small sample size, partly due to failure in sequencing of some samples and cost of resequencing. Power calculations for the differentially abundant gene statistics were conducted using the size R package (
<xref rid="B1" ref-type="bibr">Bi and Liu, 2016</xref>
) (
<bold>Supplementary Figure
<xref ref-type="supplementary-material" rid="SM5">S5</xref>
</bold>
). Also several types of patient samples were examined (stool at 2 weeks, discharge stool samples, and skin swabs) and the discharge stool sample was collected at differing ages for each patient depending on their length of stay adding further variation to the samples. However, the findings of the study are strengthened by the fact that differences in resistome and virulome between the two cohorts were detected in all sample types. The subjects of this study were carefully clinically matched but this was limited by sample size. Nevertheless, antibiotic usage and exclusive breast or donor milk feeding did differ between the two cohorts. More recently NICU practice generally has moved away from using empiric antibiotics for premature infants, with much less use of antibiotics in the new NICU than the old NICU in our study. This makes the finding of relatively more differentially abundant antibiotic resistance genes in the new NICU more intriguing and possibly more related to being a newly constructed facility. While the vast majority of infants in the new NICU (17/18) received some breast milk or donor milk, the fact that there were more infants that received exclusive breast milk or donor milk after TPN use in the old NICU may have had some influence on the microbiomes of the two cohorts (
<xref rid="B6" ref-type="bibr">Cong et al., 2016</xref>
). Nevertheless, differences in community resistome and virulome were detected in environmental samples also and not just infant samples. While this pilot study was exploratory and descriptive by nature, with clinical factors not fully controlled in both groups and with limited sample size to enable detailed further stratification by clinical features, it is the first study of its kind to give an overview of the potential environmental influences on the microbial community and its associated resistome and viruolme. Although the aim of this study was not to build associations, this will be examined in depth as the study is expanded with more individuals and samples from both environments, and critically when the new NICU has had time to “mature” and become stable through the process of ecological succession over time. Lastly, examining longitudinal microbiome development into childhood, as possible in a longitudinal cohort study such as this, is imperative to understand whether these early changes detected have any lasting impact on childhood health.</p>
</sec>
<sec>
<title>Conclusion</title>
<p>There were no differences observed in species alpha diversity between the two NICU cohorts of this study, regardless of sample type. However, differences were observed in the resistome and virulome between the two NICU cohorts, with relatively more differentially abundant antimicrobial resistance genes detected in the new NICU samples. This study highlights the influence of the NICU environment on the neonatal microbiome. Whether differences observed in the new NICU compared with the old NICU samples were related to a single-family NICU or a newly opened building warrants further exploration. Moreover, whether long term health outcomes derive from the differences in microbiomes detected between the two cohorts will be followed longitudinally in this ongoing research.</p>
</sec>
<sec>
<title>Declarations</title>
<sec>
<title>Ethics Approval and Consent to Participate</title>
<p>This study was approved by the Inova Human Research Protection program; IRB approval #15-1945. All subjects underwent informed consent to participate.</p>
</sec>
<sec>
<title>Availability of Data and Material</title>
<p>Sequence data were deposited in to NCBI Bioproject under accession number
<ext-link ext-link-type="DDBJ/EMBL/GenBank" xlink:href="PRJNA417283">PRJNA417283</ext-link>
.</p>
</sec>
</sec>
<sec>
<title>Author Contributions</title>
<p>SH, EK, KH, RB, RLB, and JN designed the study. VD, EK, and SL recruited and consented patients and collected subjects samples. AT and NaC clinically phenotyped subjects. NiC processed and quality controlled samples. PS, NH, and RC analyzed and interpreted metagenomic sequencing data. SH drafted the manuscript. All authors read and approved the final manuscript.</p>
</sec>
<sec>
<title>Conflict of Interest Statement</title>
<p>The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.</p>
</sec>
</body>
<back>
<fn-group>
<fn fn-type="financial-disclosure">
<p>
<bold>Funding.</bold>
This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors.</p>
</fn>
</fn-group>
<ack>
<p>The authors thank Kristy and Roger Crombie for their generous philanthropic donation toward this project.</p>
</ack>
<sec sec-type="supplementary material">
<title>Supplementary Material</title>
<p>The Supplementary Material for this article can be found online at:
<ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/10.3389/fmicb.2018.01361/full#supplementary-material">https://www.frontiersin.org/articles/10.3389/fmicb.2018.01361/full#supplementary-material</ext-link>
</p>
<supplementary-material content-type="local-data" id="SM1A">
<label>FIGURE S1(A)</label>
<caption>
<p>Heat maps showing the relative abundance of genera in 2-week and discharge stool samples between samples from the old NICU and the new NICU, stratified by if the infant was primarily receiving breast milk at the time of the sample collection.</p>
</caption>
<media xlink:href="Image_1.JPEG">
<caption>
<p>Click here for additional data file.</p>
</caption>
</media>
</supplementary-material>
<supplementary-material content-type="local-data" id="SM1B">
<label>FIGURE S1(B)</label>
<caption>
<p>Heat maps showing the relative abundance of genera in skin samples between samples from the old NICU and the new NICU.</p>
</caption>
<media xlink:href="Image_2.JPEG">
<caption>
<p>Click here for additional data file.</p>
</caption>
</media>
</supplementary-material>
<supplementary-material content-type="local-data" id="SM1C">
<label>FIGURE S1(C)</label>
<caption>
<p>Heat maps showing the relative abundance of genera in environmental samples between samples from the old NICU and the new NICU.</p>
</caption>
<media xlink:href="Image_3.JPEG">
<caption>
<p>Click here for additional data file.</p>
</caption>
</media>
</supplementary-material>
<supplementary-material content-type="local-data" id="SM2">
<label>FIGURE S2</label>
<caption>
<p>PCoA biplot of bacterial content at the taxonomic level of class for 2 week and discharge stool samples, comparing old and new NICU after removal of outliers. Interestingly outliers from the old and new NICU, shown in the bottom left of figure reveal clustering on different sides of the plot. Arrows point in the direction of highest correlation between taxa and sample clusters and are colored by phyla.</p>
</caption>
<media xlink:href="Image_4.JPEG">
<caption>
<p>Click here for additional data file.</p>
</caption>
</media>
</supplementary-material>
<supplementary-material content-type="local-data" id="SM3A">
<label>FIGURE S3A</label>
<caption>
<p>Antimicrobial resistance genes showing more than a two-fold log change in prevalence in samples collected from infants in the new NICU compared to the old NICU samples, in infants who had received antibiotics.</p>
</caption>
<media xlink:href="Image_5.JPEG">
<caption>
<p>Click here for additional data file.</p>
</caption>
</media>
</supplementary-material>
<supplementary-material content-type="local-data" id="SM3B">
<label>FIGURE S3B</label>
<caption>
<p>Antimicrobial resistance genes showing more than a two-fold log change in prevalence in samples collected from infants in the new NICU compared to the old NICU samples, in infants who did not receive antibiotics.</p>
</caption>
<media xlink:href="Image_6.JPEG">
<caption>
<p>Click here for additional data file.</p>
</caption>
</media>
</supplementary-material>
<supplementary-material content-type="local-data" id="SM4A">
<label>FIGURE S4A</label>
<caption>
<p>Antimicrobial resistance genes showing more than a two-fold log change in prevalence in samples collected from infants in the new NICU compared to the old NICU samples, in infants who primarily received breast milk.</p>
</caption>
<media xlink:href="Image_7.JPEG">
<caption>
<p>Click here for additional data file.</p>
</caption>
</media>
</supplementary-material>
<supplementary-material content-type="local-data" id="SM4B">
<label>FIGURE S4B</label>
<caption>
<p>Antimicrobial resistance genes showing more than a two-fold log change in prevalence in samples collected from infants in the new NICU compared to the old NICU samples, in infants who did not primarily receive breast milk.</p>
</caption>
<media xlink:href="Image_8.JPEG">
<caption>
<p>Click here for additional data file.</p>
</caption>
</media>
</supplementary-material>
<supplementary-material content-type="local-data" id="SM5">
<label>FIGURE S5</label>
<caption>
<p>Average power versus sample size for differential gene abundance test using false discovery rate of 0.05. π0 is the estimated proportion of genes which are not differentially abundant.</p>
</caption>
<media xlink:href="Image_9.JPEG">
<caption>
<p>Click here for additional data file.</p>
</caption>
</media>
</supplementary-material>
</sec>
<ref-list>
<title>References</title>
<ref id="B1">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Bi</surname>
<given-names>R.</given-names>
</name>
<name>
<surname>Liu</surname>
<given-names>P.</given-names>
</name>
</person-group>
(
<year>2016</year>
).
<article-title>Sample size calculation while controlling false discovery rate for differential expression analysis with RNA-sequencing experiments.</article-title>
<source>
<italic>BMC Bioinformatics</italic>
</source>
<volume>17</volume>
:
<issue>146</issue>
.
<pub-id pub-id-type="doi">10.1186/s12859-016-0994-9</pub-id>
<pub-id pub-id-type="pmid">27029470</pub-id>
</mixed-citation>
</ref>
<ref id="B2">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Boyle</surname>
<given-names>E. M.</given-names>
</name>
<name>
<surname>Poulsen</surname>
<given-names>G.</given-names>
</name>
<name>
<surname>Field</surname>
<given-names>G. J.</given-names>
</name>
<name>
<surname>Kurinczuk</surname>
<given-names>J. J.</given-names>
</name>
<name>
<surname>Wolke</surname>
<given-names>D.</given-names>
</name>
<name>
<surname>Alfirevic</surname>
<given-names>Z.</given-names>
</name>
<etal></etal>
</person-group>
(
<year>2012</year>
).
<article-title>Effects of gestational age at birth on health outcomes at 3 and 5 years of age: population based cohort study.</article-title>
<source>
<italic>BMJ</italic>
</source>
<volume>344</volume>
:
<issue>e896</issue>
.
<pub-id pub-id-type="doi">10.1136/bmj.e896</pub-id>
<pub-id pub-id-type="pmid">22381676</pub-id>
</mixed-citation>
</ref>
<ref id="B3">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Brooks</surname>
<given-names>B.</given-names>
</name>
<name>
<surname>Firek</surname>
<given-names>B. A.</given-names>
</name>
<name>
<surname>Miller</surname>
<given-names>C. S.</given-names>
</name>
<name>
<surname>Sharon</surname>
<given-names>I.</given-names>
</name>
<name>
<surname>Thomas</surname>
<given-names>B. C.</given-names>
</name>
<name>
<surname>Baker</surname>
<given-names>R.</given-names>
</name>
<etal></etal>
</person-group>
(
<year>2014</year>
).
<article-title>Microbes in the neonatal intensive care unit resemble those found in the gut of premature infants.</article-title>
<source>
<italic>Microbiome</italic>
</source>
<volume>2</volume>
:
<issue>1</issue>
.
<pub-id pub-id-type="doi">10.1186/2049-2618-2-1</pub-id>
<pub-id pub-id-type="pmid">24468033</pub-id>
</mixed-citation>
</ref>
<ref id="B4">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Capone</surname>
<given-names>K. A.</given-names>
</name>
<name>
<surname>Dowd</surname>
<given-names>S. E.</given-names>
</name>
<name>
<surname>Stamatas</surname>
<given-names>G. N.</given-names>
</name>
<name>
<surname>Nikolovski</surname>
<given-names>J.</given-names>
</name>
</person-group>
(
<year>2011</year>
).
<article-title>Diversity of the human skin microbiome early in life.</article-title>
<source>
<italic>J. Invest. Dermatol.</italic>
</source>
<volume>131</volume>
<fpage>2026</fpage>
<lpage>2032</lpage>
.
<pub-id pub-id-type="doi">10.1038/jid.2011.168</pub-id>
<pub-id pub-id-type="pmid">21697884</pub-id>
</mixed-citation>
</ref>
<ref id="B5">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Collins</surname>
<given-names>S. M.</given-names>
</name>
</person-group>
(
<year>2014</year>
).
<article-title>A role for the gut microbiota in IBS.</article-title>
<source>
<italic>Nat. Rev. Gastroenterol. Hepatol.</italic>
</source>
<volume>11</volume>
<fpage>497</fpage>
<lpage>505</lpage>
.
<pub-id pub-id-type="doi">10.1038/nrgastro.2014.40</pub-id>
<pub-id pub-id-type="pmid">24751910</pub-id>
</mixed-citation>
</ref>
<ref id="B6">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Cong</surname>
<given-names>X.</given-names>
</name>
<name>
<surname>Xu</surname>
<given-names>W.</given-names>
</name>
<name>
<surname>Janton</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Henderson</surname>
<given-names>W. A.</given-names>
</name>
<name>
<surname>Matson</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>McGrath</surname>
<given-names>J. M.</given-names>
</name>
<etal></etal>
</person-group>
(
<year>2016</year>
).
<article-title>Gut microbiome developmental patterns in early life of preterm infants: impacts of feeding and gender.</article-title>
<source>
<italic>PLoS One</italic>
</source>
<volume>11</volume>
:
<issue>e0152751</issue>
.
<pub-id pub-id-type="doi">10.1371/journal.pone.0152751</pub-id>
<pub-id pub-id-type="pmid">27111847</pub-id>
</mixed-citation>
</ref>
<ref id="B7">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Costello</surname>
<given-names>E. K.</given-names>
</name>
<name>
<surname>Carlisle</surname>
<given-names>E. M.</given-names>
</name>
<name>
<surname>Bik</surname>
<given-names>E. M.</given-names>
</name>
<name>
<surname>Morowitz</surname>
<given-names>M. J.</given-names>
</name>
<name>
<surname>Relman</surname>
<given-names>D. A.</given-names>
</name>
</person-group>
(
<year>2013</year>
).
<article-title>Microbiome assembly across multiple body sites in low-birthweight infants.</article-title>
<source>
<italic>mBio</italic>
</source>
<volume>4</volume>
:
<issue>e00782-13</issue>
.
<pub-id pub-id-type="doi">10.1128/mBio.00782-13</pub-id>
<pub-id pub-id-type="pmid">24169577</pub-id>
</mixed-citation>
</ref>
<ref id="B8">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>de Boer</surname>
<given-names>R.</given-names>
</name>
<name>
<surname>Peters</surname>
<given-names>R.</given-names>
</name>
<name>
<surname>Gierveld</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Schuurman</surname>
<given-names>T.</given-names>
</name>
<name>
<surname>Kooistra-Smid</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Savelkoul</surname>
<given-names>P.</given-names>
</name>
</person-group>
(
<year>2010</year>
).
<article-title>Improved detection of microbial DNA after bead-beating before DNA isolation.</article-title>
<source>
<italic>J. Microbiol. Methods</italic>
</source>
<volume>80</volume>
<fpage>209</fpage>
<lpage>211</lpage>
.
<pub-id pub-id-type="doi">10.1016/j.mimet.2009.11.009</pub-id>
<pub-id pub-id-type="pmid">19995580</pub-id>
</mixed-citation>
</ref>
<ref id="B9">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Domanico</surname>
<given-names>R.</given-names>
</name>
<name>
<surname>Davis</surname>
<given-names>D. K.</given-names>
</name>
<name>
<surname>Coleman</surname>
<given-names>F.</given-names>
</name>
<name>
<surname>Davis</surname>
<given-names>B. O.</given-names>
</name>
</person-group>
(
<year>2011</year>
).
<article-title>Documenting the NICU design dilemma: comparative patient progress in open-ward and single family room units.</article-title>
<source>
<italic>J. Perinatol.</italic>
</source>
<volume>31</volume>
<fpage>281</fpage>
<lpage>288</lpage>
.
<pub-id pub-id-type="doi">10.1038/jp.2010.120</pub-id>
<pub-id pub-id-type="pmid">21072040</pub-id>
</mixed-citation>
</ref>
<ref id="B10">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Echarri</surname>
<given-names>P. P.</given-names>
</name>
<name>
<surname>Graciá</surname>
<given-names>C. M.</given-names>
</name>
<name>
<surname>Berruezo</surname>
<given-names>G. R.</given-names>
</name>
<name>
<surname>Vives</surname>
<given-names>I.</given-names>
</name>
<name>
<surname>Ballesta</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Solís</surname>
<given-names>G.</given-names>
</name>
<etal></etal>
</person-group>
(
<year>2011</year>
).
<article-title>Assessment of intestinal microbiota of full-term breast-fed infants from two different geographical locations.</article-title>
<source>
<italic>Early Hum. Dev.</italic>
</source>
<volume>87</volume>
<fpage>511</fpage>
<lpage>513</lpage>
.
<pub-id pub-id-type="doi">10.1016/j.earlhumdev.2011.03.013</pub-id>
<pub-id pub-id-type="pmid">21501935</pub-id>
</mixed-citation>
</ref>
<ref id="B11">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Fallani</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Young</surname>
<given-names>D.</given-names>
</name>
<name>
<surname>Scott</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Norin</surname>
<given-names>E.</given-names>
</name>
<name>
<surname>Amarri</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Adam</surname>
<given-names>R.</given-names>
</name>
<etal></etal>
</person-group>
(
<year>2010</year>
).
<article-title>Intestinal microbiota of 6-week-old infants across Europe: geographic influence beyond delivery mode, breast-feeding, and antibiotics.</article-title>
<source>
<italic>J. Pediatr. Gastroenterol. Nutr.</italic>
</source>
<volume>51</volume>
<fpage>77</fpage>
<lpage>84</lpage>
.
<pub-id pub-id-type="doi">10.1097/MPG.0b013e3181d1b11e</pub-id>
<pub-id pub-id-type="pmid">20479681</pub-id>
</mixed-citation>
</ref>
<ref id="B12">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Fan</surname>
<given-names>W.</given-names>
</name>
<name>
<surname>Li</surname>
<given-names>X.</given-names>
</name>
<name>
<surname>Yang</surname>
<given-names>L.</given-names>
</name>
<name>
<surname>Huo</surname>
<given-names>G.</given-names>
</name>
</person-group>
(
<year>2014</year>
).
<article-title>Comparison of DNA extraction methods for polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) analysis of the infant fecal microbial communities.</article-title>
<source>
<italic>Afr. J. Microbiol. Res.</italic>
</source>
<volume>8</volume>
<fpage>908</fpage>
<lpage>914</lpage>
.
<pub-id pub-id-type="doi">10.5897/AJMR12.2206</pub-id>
</mixed-citation>
</ref>
<ref id="B13">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Frank</surname>
<given-names>D. N.</given-names>
</name>
<name>
<surname>St Amand</surname>
<given-names>A. L.</given-names>
</name>
<name>
<surname>Feldman</surname>
<given-names>R. A.</given-names>
</name>
<name>
<surname>Boedeker</surname>
<given-names>E. C.</given-names>
</name>
<name>
<surname>Harpaz</surname>
<given-names>N.</given-names>
</name>
<name>
<surname>Pace</surname>
<given-names>N. R.</given-names>
</name>
</person-group>
(
<year>2007</year>
).
<article-title>Molecular-phylogenetic characterization of microbial community imbalances in human inflammatory bowel diseases.</article-title>
<source>
<italic>Proc. Natl. Acad. Sci. U.S.A.</italic>
</source>
<volume>104</volume>
<fpage>13780</fpage>
<lpage>13785</lpage>
.
<pub-id pub-id-type="doi">10.1073/pnas.0706625104</pub-id>
<pub-id pub-id-type="pmid">17699621</pub-id>
</mixed-citation>
</ref>
<ref id="B14">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Fujimura</surname>
<given-names>K. E.</given-names>
</name>
<name>
<surname>Demoor</surname>
<given-names>T.</given-names>
</name>
<name>
<surname>Rauch</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Faruqi</surname>
<given-names>A. A.</given-names>
</name>
<name>
<surname>Jang</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Johnson</surname>
<given-names>C. C.</given-names>
</name>
<etal></etal>
</person-group>
(
<year>2014</year>
).
<article-title>House dust exposure mediates gut microbiome
<italic>Lactobacillus</italic>
enrichment and airway immune defense against allergens and virus infection.</article-title>
<source>
<italic>Proc. Natl. Acad. Sci. U.S.A.</italic>
</source>
<volume>111</volume>
<fpage>805</fpage>
<lpage>810</lpage>
.
<pub-id pub-id-type="doi">10.1073/pnas.1310750111</pub-id>
<pub-id pub-id-type="pmid">24344318</pub-id>
</mixed-citation>
</ref>
<ref id="B15">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Gasparrini</surname>
<given-names>A. J.</given-names>
</name>
<name>
<surname>Crofts</surname>
<given-names>T. S.</given-names>
</name>
<name>
<surname>Gibson</surname>
<given-names>M. K.</given-names>
</name>
<name>
<surname>Tarr</surname>
<given-names>P. I.</given-names>
</name>
<name>
<surname>Warner</surname>
<given-names>B. B.</given-names>
</name>
<name>
<surname>Dantas</surname>
<given-names>G.</given-names>
</name>
</person-group>
(
<year>2016</year>
).
<article-title>Antibiotic perturbation of the preterm infant gut microbiome and resistome.</article-title>
<source>
<italic>Gut Microbes</italic>
</source>
<volume>7</volume>
<fpage>443</fpage>
<lpage>449</lpage>
.
<pub-id pub-id-type="doi">10.1080/19490976.2016.1218584</pub-id>
<pub-id pub-id-type="pmid">27472377</pub-id>
</mixed-citation>
</ref>
<ref id="B16">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Gaujoux</surname>
<given-names>R.</given-names>
</name>
<name>
<surname>Seoighe</surname>
<given-names>C.</given-names>
</name>
</person-group>
(
<year>2010</year>
).
<article-title>A flexible R package for nonnegative matrix factorization.</article-title>
<source>
<italic>BMC Bioinformatics</italic>
</source>
<volume>11</volume>
:
<issue>367</issue>
.
<pub-id pub-id-type="doi">10.1186/1471-2105-11-367</pub-id>
<pub-id pub-id-type="pmid">20598126</pub-id>
</mixed-citation>
</ref>
<ref id="B17">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Gibson</surname>
<given-names>M. K.</given-names>
</name>
<name>
<surname>Wang</surname>
<given-names>B.</given-names>
</name>
<name>
<surname>Ahmadi</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Burnham</surname>
<given-names>C.</given-names>
</name>
<name>
<surname>Tarr</surname>
<given-names>P. I.</given-names>
</name>
<name>
<surname>Warner</surname>
<given-names>B. B.</given-names>
</name>
<etal></etal>
</person-group>
(
<year>2016</year>
).
<article-title>Developmental dynamics of the preterm infant gut microbiota and antibiotic resistome.</article-title>
<source>
<italic>Nat. Microbiol.</italic>
</source>
<volume>1</volume>
:
<issue>16024</issue>
.
<pub-id pub-id-type="doi">10.1038/nmicrobiol.2016.24</pub-id>
<pub-id pub-id-type="pmid">27572443</pub-id>
</mixed-citation>
</ref>
<ref id="B18">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Hasan</surname>
<given-names>N. A.</given-names>
</name>
<name>
<surname>Young</surname>
<given-names>B. A.</given-names>
</name>
<name>
<surname>Minard-Smith</surname>
<given-names>A. T.</given-names>
</name>
<name>
<surname>Saeed</surname>
<given-names>K.</given-names>
</name>
<name>
<surname>Li</surname>
<given-names>H.</given-names>
</name>
<name>
<surname>Heizer</surname>
<given-names>E. M.</given-names>
</name>
<etal></etal>
</person-group>
(
<year>2014</year>
).
<article-title>Microbial community profiling of human saliva using shotgun metagenomic sequencing.</article-title>
<source>
<italic>PLoS One</italic>
</source>
<volume>9</volume>
:
<issue>e97699</issue>
.
<pub-id pub-id-type="doi">10.1371/journal.pone.0097699</pub-id>
<pub-id pub-id-type="pmid">24846174</pub-id>
</mixed-citation>
</ref>
<ref id="B19">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Hewitt</surname>
<given-names>K. M.</given-names>
</name>
<name>
<surname>Mannino</surname>
<given-names>F. L.</given-names>
</name>
<name>
<surname>Gonzalez</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Chase</surname>
<given-names>J. H.</given-names>
</name>
<name>
<surname>Caporaso</surname>
<given-names>J. G.</given-names>
</name>
<name>
<surname>Knight</surname>
<given-names>R.</given-names>
</name>
<etal></etal>
</person-group>
(
<year>2013</year>
).
<article-title>Bacterial diversity in two neonatal intensive care units (NICUs).</article-title>
<source>
<italic>PLoS One</italic>
</source>
<volume>8</volume>
:
<issue>e54703</issue>
.
<pub-id pub-id-type="doi">10.1371/journal.pone.0054703</pub-id>
<pub-id pub-id-type="pmid">23372757</pub-id>
</mixed-citation>
</ref>
<ref id="B20">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Hsiao</surname>
<given-names>E. Y.</given-names>
</name>
<name>
<surname>McBride</surname>
<given-names>S. W.</given-names>
</name>
<name>
<surname>Hsien</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Sharon</surname>
<given-names>G.</given-names>
</name>
<name>
<surname>Hyde</surname>
<given-names>E. R.</given-names>
</name>
<name>
<surname>McCue</surname>
<given-names>T.</given-names>
</name>
<etal></etal>
</person-group>
(
<year>2013</year>
).
<article-title>Microbiota modulate behavioral and physiological abnormalities associated with neurodevelopmental disorders.</article-title>
<source>
<italic>Cell</italic>
</source>
<volume>155</volume>
<fpage>1451</fpage>
<lpage>1463</lpage>
.
<pub-id pub-id-type="doi">10.1016/j.cell.2013.11.024</pub-id>
<pub-id pub-id-type="pmid">24315484</pub-id>
</mixed-citation>
</ref>
<ref id="B21">
<mixed-citation publication-type="book">
<person-group person-group-type="author">
<name>
<surname>Kaufman</surname>
<given-names>L.</given-names>
</name>
<name>
<surname>Rousseeuw</surname>
<given-names>P. J.</given-names>
</name>
</person-group>
(
<year>1987</year>
).
<article-title>“Clustering by means of medoids,” in</article-title>
<source>
<italic>Statistical Data Analysis Based on the L1 - Norm and Related Methods</italic>
</source>
,
<edition>ed</edition>
<name>
<surname>Dodge</surname>
<given-names>Y.</given-names>
</name>
(
<publisher-loc>New York, NY</publisher-loc>
:
<publisher-name>Elsevier Science</publisher-name>
),
<fpage>405</fpage>
<lpage>416</lpage>
.</mixed-citation>
</ref>
<ref id="B22">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Kennedy</surname>
<given-names>E. A.</given-names>
</name>
<name>
<surname>Connolly</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Hourihane</surname>
<given-names>J. O.</given-names>
</name>
<name>
<surname>Fallon</surname>
<given-names>P. G.</given-names>
</name>
<name>
<surname>McLean</surname>
<given-names>W. H. I.</given-names>
</name>
<name>
<surname>Murray</surname>
<given-names>D.</given-names>
</name>
<etal></etal>
</person-group>
(
<year>2017</year>
).
<article-title>Skin microbiome before development of atopic dermatitis: early colonization with commensal staphylococci at 2 months is associated with a lower risk of atopic dermatitis at 1 year.</article-title>
<source>
<italic>J. Allergy Clin. Immunol.</italic>
</source>
<volume>139</volume>
<fpage>166</fpage>
<lpage>172</lpage>
.
<pub-id pub-id-type="doi">10.1016/j.jaci.2016.07.029</pub-id>
<pub-id pub-id-type="pmid">27609659</pub-id>
</mixed-citation>
</ref>
<ref id="B23">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Khelaifia</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Ramonet</surname>
<given-names>P.-Y.</given-names>
</name>
<name>
<surname>Bedotto Buffet</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Drancourt</surname>
<given-names>M.</given-names>
</name>
</person-group>
(
<year>2013</year>
).
<article-title>A semi-automated protocol for Archaea DNA extraction from stools.</article-title>
<source>
<italic>BMC Res. Notes</italic>
</source>
<volume>6</volume>
:
<issue>186</issue>
.
<pub-id pub-id-type="doi">10.1186/1756-0500-6-186</pub-id>
<pub-id pub-id-type="pmid">23651536</pub-id>
</mixed-citation>
</ref>
<ref id="B24">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>La Rosa</surname>
<given-names>P. S.</given-names>
</name>
<name>
<surname>Brooks</surname>
<given-names>J. P.</given-names>
</name>
<name>
<surname>Deych</surname>
<given-names>E.</given-names>
</name>
<name>
<surname>Boone</surname>
<given-names>E. L.</given-names>
</name>
<name>
<surname>Edwards</surname>
<given-names>D. J.</given-names>
</name>
<name>
<surname>Wang</surname>
<given-names>Q.</given-names>
</name>
<etal></etal>
</person-group>
(
<year>2012</year>
).
<article-title>Hypothesis testing and power calculations for taxonomic-based human microbiome data.</article-title>
<source>
<italic>PLoS One</italic>
</source>
<volume>7</volume>
:
<issue>e52078</issue>
.
<pub-id pub-id-type="doi">10.1371/journal.pone.0052078</pub-id>
<pub-id pub-id-type="pmid">23284876</pub-id>
</mixed-citation>
</ref>
<ref id="B25">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>La Rosa</surname>
<given-names>P. S.</given-names>
</name>
<name>
<surname>Warner</surname>
<given-names>B. B.</given-names>
</name>
<name>
<surname>Zhou</surname>
<given-names>Y.</given-names>
</name>
<name>
<surname>Weinstock</surname>
<given-names>G. M.</given-names>
</name>
<name>
<surname>Sodergren</surname>
<given-names>E.</given-names>
</name>
<name>
<surname>Hall-Moore</surname>
<given-names>C. M.</given-names>
</name>
<etal></etal>
</person-group>
(
<year>2014</year>
).
<article-title>Patterned progression of bacterial populations in the premature infant gut.</article-title>
<source>
<italic>Proc. Natl. Acad. Sci. U.S.A.</italic>
</source>
<volume>111</volume>
<fpage>12522</fpage>
<lpage>12527</lpage>
.
<pub-id pub-id-type="doi">10.1073/pnas.1409497111</pub-id>
<pub-id pub-id-type="pmid">25114261</pub-id>
</mixed-citation>
</ref>
<ref id="B26">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Lax</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Sangwan</surname>
<given-names>N.</given-names>
</name>
<name>
<surname>Smith</surname>
<given-names>D.</given-names>
</name>
<name>
<surname>Larsen</surname>
<given-names>P.</given-names>
</name>
<name>
<surname>Handley</surname>
<given-names>K. M.</given-names>
</name>
<name>
<surname>Richardson</surname>
<given-names>M.</given-names>
</name>
<etal></etal>
</person-group>
(
<year>2017</year>
).
<article-title>Bacterial colonization and succession in a newly opened hospital.</article-title>
<source>
<italic>Sci. Transl. Med.</italic>
</source>
<volume>9</volume>
:
<issue>eaah6500</issue>
.
<pub-id pub-id-type="doi">10.1126/scitranslmed.aah6500</pub-id>
<pub-id pub-id-type="pmid">28539477</pub-id>
</mixed-citation>
</ref>
<ref id="B27">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Lax</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Smith</surname>
<given-names>D. P.</given-names>
</name>
<name>
<surname>Marcell</surname>
<given-names>J. H.</given-names>
</name>
<name>
<surname>Owens</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Handley</surname>
<given-names>K.</given-names>
</name>
<name>
<surname>Scott</surname>
<given-names>K.</given-names>
</name>
<etal></etal>
</person-group>
(
<year>2014</year>
).
<article-title>Longitudinal analysis of microbial interaction between humans and the indoor environment.</article-title>
<source>
<italic>Science</italic>
</source>
<volume>345</volume>
<fpage>1048</fpage>
<lpage>1052</lpage>
.
<pub-id pub-id-type="doi">10.1126/science.1254529</pub-id>
<pub-id pub-id-type="pmid">25170151</pub-id>
</mixed-citation>
</ref>
<ref id="B28">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Manichanh</surname>
<given-names>C.</given-names>
</name>
<name>
<surname>Borruel</surname>
<given-names>N.</given-names>
</name>
<name>
<surname>Casellas</surname>
<given-names>F.</given-names>
</name>
<name>
<surname>Guarner</surname>
<given-names>F.</given-names>
</name>
</person-group>
(
<year>2012</year>
).
<article-title>The gut microbiota in IBD.</article-title>
<source>
<italic>Nat. Rev. Gastroenterol. Hepatol.</italic>
</source>
<volume>9</volume>
<fpage>599</fpage>
<lpage>608</lpage>
.
<pub-id pub-id-type="doi">10.1038/nrgastro.2012.152</pub-id>
<pub-id pub-id-type="pmid">22907164</pub-id>
</mixed-citation>
</ref>
<ref id="B29">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Marks</surname>
<given-names>L. R.</given-names>
</name>
<name>
<surname>Clementi</surname>
<given-names>E. A.</given-names>
</name>
<name>
<surname>Hakansson</surname>
<given-names>A. P.</given-names>
</name>
</person-group>
(
<year>2013</year>
).
<article-title>Sensitization of Staphylococcus aureus to methicillin and other antibiotics
<italic>in vitro</italic>
and
<italic>in vivo</italic>
in the presence of HAMLET.</article-title>
<source>
<italic>PLoS One</italic>
</source>
<volume>8</volume>
:
<issue>e63158</issue>
.
<pub-id pub-id-type="doi">10.1371/journal.pone.0063158</pub-id>
<pub-id pub-id-type="pmid">23650551</pub-id>
</mixed-citation>
</ref>
<ref id="B30">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>McGill</surname>
<given-names>R.</given-names>
</name>
<name>
<surname>Tukey</surname>
<given-names>J. W.</given-names>
</name>
<name>
<surname>Larsen</surname>
<given-names>W. A.</given-names>
</name>
</person-group>
(
<year>1978</year>
).
<article-title>Variations of box plots.</article-title>
<source>
<italic>Am. Stat.</italic>
</source>
<volume>32</volume>
<fpage>12</fpage>
<lpage>16</lpage>
.</mixed-citation>
</ref>
<ref id="B31">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Moles</surname>
<given-names>L.</given-names>
</name>
<name>
<surname>Gómez</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Heilig</surname>
<given-names>H.</given-names>
</name>
<name>
<surname>Bustos</surname>
<given-names>G.</given-names>
</name>
<name>
<surname>Fuentes</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>de Vos</surname>
<given-names>W.</given-names>
</name>
<etal></etal>
</person-group>
(
<year>2013</year>
).
<article-title>Bacterial diversity in meconium of preterm neonates and evolution of their fecal microbiota during the first month of life.</article-title>
<source>
<italic>PLoS One</italic>
</source>
<volume>8</volume>
:
<issue>e66986</issue>
.
<pub-id pub-id-type="doi">10.1371/journal.pone.0066986</pub-id>
<pub-id pub-id-type="pmid">23840569</pub-id>
</mixed-citation>
</ref>
<ref id="B32">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Moles</surname>
<given-names>L.</given-names>
</name>
<name>
<surname>Gómez</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Jiménez</surname>
<given-names>E.</given-names>
</name>
<name>
<surname>Fernández</surname>
<given-names>L.</given-names>
</name>
<name>
<surname>Bustos</surname>
<given-names>G.</given-names>
</name>
<name>
<surname>Chaves</surname>
<given-names>F.</given-names>
</name>
<etal></etal>
</person-group>
(
<year>2015</year>
).
<article-title>Preterm infant gut colonization in the neonatal ICU and complete restoration 2 years later.</article-title>
<source>
<italic>Clin. Microbiol. Infect.</italic>
</source>
<volume>21</volume>
<issue>936</issue>
.
<fpage>e1</fpage>
<lpage>936</lpage>
.e10.
<pub-id pub-id-type="doi">10.1016/j.cmi.2015.06.003</pub-id>
<pub-id pub-id-type="pmid">25636943</pub-id>
</mixed-citation>
</ref>
<ref id="B33">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Ortenstrand</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Westrup</surname>
<given-names>B.</given-names>
</name>
<name>
<surname>Broström</surname>
<given-names>E. B.</given-names>
</name>
<name>
<surname>Sarman</surname>
<given-names>I.</given-names>
</name>
<name>
<surname>Akerström</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Brune</surname>
<given-names>T.</given-names>
</name>
<etal></etal>
</person-group>
(
<year>2010</year>
).
<article-title>The stockholm neonatal family centered care study: effects on length of stay and infant morbidity.</article-title>
<source>
<italic>Pediatrics</italic>
</source>
<volume>125</volume>
<fpage>e278</fpage>
<lpage>e285</lpage>
.
<pub-id pub-id-type="doi">10.1542/peds.2009-1511</pub-id>
<pub-id pub-id-type="pmid">20100748</pub-id>
</mixed-citation>
</ref>
<ref id="B34">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Pammi</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Cope</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Tarr</surname>
<given-names>P. I.</given-names>
</name>
<name>
<surname>Warner</surname>
<given-names>B. B.</given-names>
</name>
<name>
<surname>Morrow</surname>
<given-names>A. L.</given-names>
</name>
<name>
<surname>Mai</surname>
<given-names>V.</given-names>
</name>
<etal></etal>
</person-group>
(
<year>2017a</year>
).
<article-title>Intestinal dysbiosis in preterm infants preceding necrotizing enterocolitis: a systematic review and meta-analysis.</article-title>
<source>
<italic>Microbiome</italic>
</source>
<volume>5</volume>
:
<issue>31</issue>
.
<pub-id pub-id-type="doi">10.1186/s40168-017-0248-8</pub-id>
<pub-id pub-id-type="pmid">28274256</pub-id>
</mixed-citation>
</ref>
<ref id="B35">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Pammi</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>O’Brien</surname>
<given-names>J. L.</given-names>
</name>
<name>
<surname>Ajami</surname>
<given-names>N. J.</given-names>
</name>
<name>
<surname>Wong</surname>
<given-names>M. C.</given-names>
</name>
<name>
<surname>Versalovic</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Petrosino</surname>
<given-names>J. F.</given-names>
</name>
</person-group>
(
<year>2017b</year>
).
<article-title>Development of the cutaneous microbiome in the preterm infant: a prospective longitudinal study.</article-title>
<source>
<italic>PLoS One</italic>
</source>
<volume>12</volume>
:
<issue>e0176669</issue>
.
<pub-id pub-id-type="doi">10.1371/journal.pone.0176669</pub-id>
<pub-id pub-id-type="pmid">28448623</pub-id>
</mixed-citation>
</ref>
<ref id="B36">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Ponnusamy</surname>
<given-names>D.</given-names>
</name>
<name>
<surname>Kozlova</surname>
<given-names>E. V.</given-names>
</name>
<name>
<surname>Sha</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Erova</surname>
<given-names>T. E.</given-names>
</name>
<name>
<surname>Azar</surname>
<given-names>S. R.</given-names>
</name>
<name>
<surname>Fitts</surname>
<given-names>E. C.</given-names>
</name>
<etal></etal>
</person-group>
(
<year>2016</year>
).
<article-title>Cross-talk among flesh-eating Aeromonas hydrophila strains in mixed infection leading to necrotizing fasciitis.</article-title>
<source>
<italic>Proc. Natl. Acad. Sci. U.S.A.</italic>
</source>
<volume>113</volume>
<fpage>722</fpage>
<lpage>727</lpage>
.
<pub-id pub-id-type="doi">10.1073/pnas.1523817113</pub-id>
<pub-id pub-id-type="pmid">26733683</pub-id>
</mixed-citation>
</ref>
<ref id="B37">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Sadatsafavi</surname>
<given-names>H.</given-names>
</name>
<name>
<surname>Niknejad</surname>
<given-names>B.</given-names>
</name>
<name>
<surname>Shepley</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Sadatsafavi</surname>
<given-names>M.</given-names>
</name>
</person-group>
(
<year>2017</year>
).
<article-title>Probabilistic return-on-investment analysis of single-family versus open-bay rooms in neonatal intensive care units-synthesis and evaluation of early evidence on nosocomial infections, length of stay, and direct cost of care.</article-title>
<source>
<italic>J Intensive Care Med.</italic>
</source>
<pub-id pub-id-type="doi">10.1177/0885066616689774</pub-id>
<comment>[Epub ahead of print].</comment>
<pub-id pub-id-type="pmid">28118769</pub-id>
</mixed-citation>
</ref>
<ref id="B38">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Saiman</surname>
<given-names>L.</given-names>
</name>
</person-group>
(
<year>2002</year>
).
<article-title>Risk factors for hospital-acquired infections in the neonatal intensive care unit.</article-title>
<source>
<italic>Semin. Perinatol.</italic>
</source>
<volume>26</volume>
<fpage>315</fpage>
<lpage>321</lpage>
.
<pub-id pub-id-type="doi">10.1053/sper.2002.36264</pub-id>
<pub-id pub-id-type="pmid">12452503</pub-id>
</mixed-citation>
</ref>
<ref id="B39">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Salonen</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Nikkilä</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Jalanka-Tuovinen</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Immonen</surname>
<given-names>O.</given-names>
</name>
<name>
<surname>Rajilić-Stojanović</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Kekkonen</surname>
<given-names>R. A.</given-names>
</name>
<etal></etal>
</person-group>
(
<year>2010</year>
).
<article-title>Comparative analysis of fecal DNA extraction methods with phylogenetic microarray: effective recovery of bacterial and archaeal DNA using mechanical cell lysis.</article-title>
<source>
<italic>J. Microbiol. Methods</italic>
</source>
<volume>81</volume>
<fpage>127</fpage>
<lpage>134</lpage>
.
<pub-id pub-id-type="doi">10.1016/j.mimet.2010.02.007</pub-id>
<pub-id pub-id-type="pmid">20171997</pub-id>
</mixed-citation>
</ref>
<ref id="B40">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Stevens</surname>
<given-names>D. C.</given-names>
</name>
<name>
<surname>Thompson</surname>
<given-names>P. A.</given-names>
</name>
<name>
<surname>Helseth</surname>
<given-names>C. C.</given-names>
</name>
<name>
<surname>Hsu</surname>
<given-names>B.</given-names>
</name>
<name>
<surname>Khan</surname>
<given-names>M. A.</given-names>
</name>
<name>
<surname>Munson</surname>
<given-names>D. P.</given-names>
</name>
</person-group>
(
<year>2014</year>
).
<article-title>A comparison of the direct cost of care in an open-bay and single-family room NICU.</article-title>
<source>
<italic>J. Perinatol.</italic>
</source>
<volume>34</volume>
<fpage>830</fpage>
<lpage>835</lpage>
.
<pub-id pub-id-type="doi">10.1038/jp.2014.178</pub-id>
<pub-id pub-id-type="pmid">25254332</pub-id>
</mixed-citation>
</ref>
<ref id="B41">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Tarkkanen</surname>
<given-names>A. M.</given-names>
</name>
<name>
<surname>Heinonen</surname>
<given-names>T.</given-names>
</name>
<name>
<surname>Jõgi</surname>
<given-names>R.</given-names>
</name>
<name>
<surname>Mentula</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>van der Rest</surname>
<given-names>M. E.</given-names>
</name>
<name>
<surname>Donskey</surname>
<given-names>C. J.</given-names>
</name>
<etal></etal>
</person-group>
(
<year>2009</year>
).
<article-title>P1A recombinant beta-lactamase prevents emergence of antimicrobial resistance in gut microflora of healthy subjects during intravenous administration of ampicillin.</article-title>
<source>
<italic>Antimicrob. Agents Chemother.</italic>
</source>
<volume>53</volume>
<fpage>2455</fpage>
<lpage>2462</lpage>
.
<pub-id pub-id-type="doi">10.1128/AAC.00853-08</pub-id>
<pub-id pub-id-type="pmid">19307374</pub-id>
</mixed-citation>
</ref>
<ref id="B42">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Tilg</surname>
<given-names>H.</given-names>
</name>
<name>
<surname>Kaser</surname>
<given-names>A.</given-names>
</name>
</person-group>
(
<year>2011</year>
).
<article-title>Gut microbiome, obesity, and metabolic dysfunction.</article-title>
<source>
<italic>J. Clin. Invest.</italic>
</source>
<volume>121</volume>
<fpage>2126</fpage>
<lpage>2132</lpage>
.
<pub-id pub-id-type="doi">10.1172/JCI58109</pub-id>
<pub-id pub-id-type="pmid">21633181</pub-id>
</mixed-citation>
</ref>
<ref id="B43">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Walsh</surname>
<given-names>W. F.</given-names>
</name>
<name>
<surname>McCullough</surname>
<given-names>K. L.</given-names>
</name>
<name>
<surname>White</surname>
<given-names>R. D.</given-names>
</name>
</person-group>
(
<year>2006</year>
).
<article-title>Room for improvement: nurses’ perceptions of providing care in a single room newborn intensive care setting.</article-title>
<source>
<italic>Adv. Neonatal Care</italic>
</source>
<volume>6</volume>
<fpage>261</fpage>
<lpage>270</lpage>
.
<pub-id pub-id-type="doi">10.1016/j.adnc.2006.06.002</pub-id>
<pub-id pub-id-type="pmid">17045946</pub-id>
</mixed-citation>
</ref>
<ref id="B44">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Wang</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Karlsson</surname>
<given-names>C.</given-names>
</name>
<name>
<surname>Olsson</surname>
<given-names>C.</given-names>
</name>
<name>
<surname>Adlerberth</surname>
<given-names>I.</given-names>
</name>
<name>
<surname>Wold</surname>
<given-names>A. E.</given-names>
</name>
<name>
<surname>Strachan</surname>
<given-names>D. P.</given-names>
</name>
<etal></etal>
</person-group>
(
<year>2008</year>
).
<article-title>Reduced diversity in the early fecal microbiota of infants with atopic eczema.</article-title>
<source>
<italic>J. Allergy Clin. Immunol.</italic>
</source>
<volume>121</volume>
<fpage>129</fpage>
<lpage>134</lpage>
.
<pub-id pub-id-type="doi">10.1016/j.jaci.2007.09.011</pub-id>
<pub-id pub-id-type="pmid">18028995</pub-id>
</mixed-citation>
</ref>
<ref id="B45">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>West</surname>
<given-names>C. E.</given-names>
</name>
<name>
<surname>Rydén</surname>
<given-names>P.</given-names>
</name>
<name>
<surname>Lundin</surname>
<given-names>D.</given-names>
</name>
<name>
<surname>Engstrand</surname>
<given-names>L.</given-names>
</name>
<name>
<surname>Tulic</surname>
<given-names>M. K.</given-names>
</name>
<name>
<surname>Prescott</surname>
<given-names>S. L.</given-names>
</name>
</person-group>
(
<year>2015</year>
).
<article-title>Gut microbiome and innate immune response patterns in IgE-associated eczema.</article-title>
<source>
<italic>Clin. Exp. Allergy</italic>
</source>
<volume>45</volume>
<fpage>1419</fpage>
<lpage>1429</lpage>
.
<pub-id pub-id-type="doi">10.1111/cea.12566</pub-id>
<pub-id pub-id-type="pmid">25944283</pub-id>
</mixed-citation>
</ref>
<ref id="B46">
<mixed-citation publication-type="journal">
<person-group person-group-type="author">
<name>
<surname>Yatsunenko</surname>
<given-names>T.</given-names>
</name>
<name>
<surname>Rey</surname>
<given-names>F. E.</given-names>
</name>
<name>
<surname>Manary</surname>
<given-names>M. J.</given-names>
</name>
<name>
<surname>Trehan</surname>
<given-names>I.</given-names>
</name>
<name>
<surname>Dominguez-Bello</surname>
<given-names>M. G.</given-names>
</name>
<name>
<surname>Contreras</surname>
<given-names>M.</given-names>
</name>
<etal></etal>
</person-group>
(
<year>2012</year>
).
<article-title>Human gut microbiome viewed across age and geography.</article-title>
<source>
<italic>Nature</italic>
</source>
<volume>486</volume>
<fpage>222</fpage>
<lpage>227</lpage>
.
<pub-id pub-id-type="doi">10.1038/nature11053</pub-id>
<pub-id pub-id-type="pmid">22699611</pub-id>
</mixed-citation>
</ref>
</ref-list>
</back>
</pmc>
</record>

Pour manipuler ce document sous Unix (Dilib)

EXPLOR_STEP=$WICRI_ROOT/Wicri/Sante/explor/CovidV2/Data/Pmc/Corpus
HfdSelect -h $EXPLOR_STEP/biblio.hfd -nk 000865 | SxmlIndent | more

Ou

HfdSelect -h $EXPLOR_AREA/Data/Pmc/Corpus/biblio.hfd -nk 000865 | SxmlIndent | more

Pour mettre un lien sur cette page dans le réseau Wicri

{{Explor lien
   |wiki=    Wicri/Sante
   |area=    CovidV2
   |flux=    Pmc
   |étape=   Corpus
   |type=    RBID
   |clé=     PMC:6026636
   |texte=   Comparison of Infant Gut and Skin Microbiota, Resistome and Virulome Between Neonatal Intensive Care Unit (NICU) Environments
}}

Pour générer des pages wiki

HfdIndexSelect -h $EXPLOR_AREA/Data/Pmc/Corpus/RBID.i   -Sk "pubmed:29988506" \
       | HfdSelect -Kh $EXPLOR_AREA/Data/Pmc/Corpus/biblio.hfd   \
       | NlmPubMed2Wicri -a CovidV2 

Wicri

This area was generated with Dilib version V0.6.33.
Data generation: Sat Mar 28 17:51:24 2020. Site generation: Sun Jan 31 15:35:48 2021