Category Archives: Pregnancy and birth

Human (and fish) microbiome, July 16

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Oral microbiome in children with leukemia, and effects of antibiotics on fish microbiota.

Human oral microbiome

Oral Microbiota Distinguishes Acute Lymphoblastic Leukemia Pediatric Hosts from Healthy Populations – Yan Wang – PLOS ONE

“The oral microbiota of leukemia patients had lower richness and less diversity compared to healthy controls.”

Human gut microbiome

Editorial: New bacteria associated with diarrhoea – Cláudio Nunes-Alves – Nature Reviews Microbiology

“Pop et al. used high throughput 16S rRNA sequencing to compare the faecal microbiota composition in 992 children from Gambia, Mali, Kenya and Bangladesh”

Pregnancy and birth

Yes, this one is not really microbiome-related, but it touched my heart:

Screen Shot 2014-07-16 at 11.49.15 PMStrangers help with photo in midst of tragedy – Dorrine Mendoza, CNN

“”My daughter recently passed away after a long battle in the children’s hospital. She was in the hospital her whole life and we were never able to get a photo without all her tubes. Can someone remove the tubes?””

Fish microbiome

Effects of antibiotic on the bacterial microflora in two commercially
important catfish species, Clarias batrachus and Heteropneustes fossilis in
Bangladesh – Md. Shahdat Hossain – Journal of Coastal Life Medicine

“During the experiment, bacterial loads were estimated as colony forming unit (CFU/g) by every alternate day in the aquarium water, gills, skin and intestine of fish.”

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Human microbiome, July 15

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Not-always-rare taxa in a wide range of ecosystems, microbiome in early life, focus on Lactobacillus and Bacteroides and microbiota and inflammation.

General microbiome

Science Webinar: The promise of the microbiome: Function and dysfunction in humans and beyond – David A. Relman, Jack A. Gilbert, Rob Knight

“Microbiomes–the distinct microbial populations that colonize an array of bodily and environmental niches–are rapidly gaining prominence in numerous fields of research. “

Gut microbiome

Screen shot 2014-07-15 at 05.18PM, Jul 15Conditionally Rare Taxa Disproportionately Contribute to Temporal Changes in Microbial Diversity – Ashley Shade – mBio

“Using 16S rRNA amplicon sequencing of 3,237 samples from 42 time series of microbial communities from nine different ecosystems (air; marine; lake; stream; adult human skin, tongue, and gut; infant gut; and brewery wastewater treatment), we introduce a new method to detect typically rare microbial taxa that occasionally become very abundant (conditionally rare taxa [CRT]) and then quantify their contributions to temporal shifts in community structure.”

Screen shot 2014-07-15 at 05.20PM, Jul 15Functional genomics of Lactobacillus casei establishment in the gut – Hélène Licandro-Seraut – PNAS

“By determining the relative quantity of each of the 1,110 mutants before and after the in vivo challenge, we identified a core of 47 L. casei genes necessary for its establishment in the gut. “

Screen shot 2014-07-15 at 05.21PM, Jul 15Tuning transcription of nutrient utilization genes to catabolic rate promotes growth in a gut bacterium – Varsha Raghavan – Molecular Microbiology

“We report that the regulator controlling utilization of chondroitin sulfate (CS) in the mammalian gut symbiont Bacteroides thetaiotaomicron is activated by an intermediate in CS breakdown rather than CS itself.”

Pregnancy and Birth

Screen shot 2014-07-15 at 06.38PM, Jul 15 1Review: The Microbiome in Early Life: Self-Completion and Microbiota Protection as Health Priorities – Rodney R. Dietert – Birth Defects Research Part B: Developmental and Reproductive Toxicology

“This minireview considers the benefits of refocusing attention away from treating the patient as a mammalian human to managing the complete patient: a majority microbial superorganism. “

Screen shot 2014-07-15 at 06.38PM, Jul 15Review: Anaerobes and Bacterial Vaginosis in Pregnancy: Virulence Factors Contributing to Vaginal Colonisation – Charlene W. J. Africa – Int. J. Environ. Res. Public Health

“This paper reviewed new available information regarding possible factors contributing to the establishment of the BV vaginal biofilm, examined the proposed role of anaerobic microbial species recently detected by new culture-independent methods and discusses developments related to the effects of BV on human pregnancy. “

Oral microbiome

Review: Acquisition and maturation of oral microbiome throughout childhood: An update – Benedita Sampaio-Maia – Dental Research Journal

“This revision presents an overview of this renewed knowledge on oral microbial community acquisition in the newborn and on the evolution of this microbiome to adulthood. “

 

Animal models of human microbiome and disease

Screen shot 2014-07-15 at 05.17PM, Jul 15Commensal microbes drive intestinal inflammation by IL-17–producing CD4+ T cells through ICOSL and OX40L costimulation in the absence of B7-1 and B7-2 – Lijun Xin – PNAS

“Here we show that B7 deprivation in mice overrides the necessity for Tregs in averting systemic autoimmunity and inflammation in extraintestinal tissues, whereas peripherally induced Tregs retained in the absence of B7 selectively mitigate intestinal inflammation caused by Th17 effector CD4+ T cells. “

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Human microbiome, July 14

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Ethnic variation in vaginal microbiomes, effect of chemotherapy on human milk, response of (murine) microbiota to infection.

Oral microbiome

Screen shot 2014-07-14 at 12.23PM, Jul 14Advancements toward a Systems Level Understanding of the Human Oral Microbiome – Jeffrey S. Mclean – Frontiers in Cellular and Infection Microbiology

“This review will discuss some of the recent insights into the oral microbiome at a fundamental level, existing knowledge gaps, as well as challenges that have surfaced and the approaches to address them.”

Vaginal microbiome

Screen shot 2014-07-14 at 12.24PM, Jul 14Ethnic Variations in Cervical Cytokine Concentrations and Vaginal Flora During Pregnancy – Riana Dutt – American Journal of Reproductive Immunology

“Semi-quantitative vaginal cultures and concentrations of cervical cytokines were compared between Caucasian and non-Caucasian women.”

Gut microbiome

Screen shot 2014-07-14 at 12.25PM, Jul 14A functional metabolic map of Faecalibacterium prausnitzii, a beneficial human gut microbe – Almut Heinken – Journal of Bacteriology

“In this study, we present an integrated, iterative approach of computational modeling, in vitro experiments, metabolomics and genomic analysis to accelerate the identification of metabolic capabilities for poorly characterized (anaerobic) microorganisms.”

Pregnancy and birth

Screen shot 2014-07-14 at 12.26PM, Jul 14Effect of chemotherapy on the microbiota and metabolome of human milk, a case report – Camilla Urbaniak – Microbiome

“Mature milk was collected every two weeks over a four month period from a lactating woman undergoing chemotherapy for Hodgkin’s lymphoma. Mature milk was also collected from healthy lactating women for comparison. Microbial profiles were analyzed by 16S sequencing and the metabolome by gas chromatography-mass spectrometry.”

Animal models

Clara Belzer miceDynamics of the Microbiota in Response to Host Infection – Clara Belzer – PLOS ONE

“Employing a murine model of infectious colitis with the pathogen Citrobacter rodentium, we generated a 2-month time-series of 16S rDNA gene profiles, and quantitatively cultured commensals, from multiple intestinal sites in infected and uninfected mice. “

Prune juice animal modelCarbohydrate-Free Peach (Prunus persica) and Plum (Prunus domestica) Juice Affects Fecal Microbial Ecology in an Obese Animal Model – Giuliana D. Noratto – PLOS ONE

“Fecal samples were obtained after 11 weeks of fruit or control juice administration. Real-time PCR and 454-pyrosequencing were used to evaluate changes in fecal microbiota. Over 1,500 different Operational Taxonomic Units at 97% similarity were detected in all rats.”

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Microbiome and general science digest, July 11

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Most recent results from American gut, a metagenomics pipeline, arsenic toxicity, polio and dengue vaccines, and pregnancy urine metabolomics to predict preterm birth.

Human gut microbiome

American GutAmerican Gut releases latest results and pipeline – Jeff Leach – American Gut

“The latest American Gut results are out and we’re very excited to share them with the American Gut community. We now have sequencing and analysis data from 3,238 participants, and as of today, this data equates to 101 million DNA sequences and 27 gigabytes of sequencing information.”

Screen shot 2014-07-11 at 04.27PM, Jul 11Place of upbringing in early childhood as related to inflammatory bowel diseases in adulthood: a population-based cohort study in Northern Europe – Signe Timm – European Journal of Epidemiology

“This study suggests a protective effect from livestock farm living in early childhood on the occurrence of IBD in adulthood, however only among subjects born after 1952. We speculate that lower microbial diversity is an explanation for the findings.”

Pregnancy and birth

Urinary pretermUrinary metabolic profiles in early pregnancy are associated with preterm birth and fetal growth restriction in the Rhea mother–child cohort study – Léa Maitre – BMC Medicine

“Here we used an exploratory metabolic profiling approach (metabolomics) to investigate the association between birth outcomes and metabolites in maternal urine collected early in pregnancy as part of the prospective mother–child cohort Rhea study. “

Metagenomics

MedusaMetagenomic Data Utilization and Analysis (MEDUSA) and Construction of a Global Gut Microbial Gene Catalogue – Fredrik H. Karlsson, Intawat Nookaew, Jens Nielsen – PLOS Computational Biology

“Here we present the bioinformatics pipeline MEDUSA that facilitates analysis of metagenomic reads at the gene and taxonomic level. We also constructed a global human gut microbial gene catalogue by combining data from 4 studies spanning 3 continents. “

Proteomics

Proteomics Staph aureusGenomics and Proteomics Provide New Insight into the Commensal and Pathogenic Lifestyles of Bovine and Human-associated Staphylococcus epidermidis strains – Kirsi Savijoki – Journal of Proteome Research

“Pilot experimental infection studies indicated that while ATCC12228 was able to infect bovine host, the PM221 strain caused more severe clinical signs. “

Dengue

Demanou DengueEvidence of Dengue Virus Transmission and Factors Associated with the Presence of Anti-Dengue Virus Antibodies in Humans in Three Major Towns in Cameroon – Maurice Demanou – PLOS Neglected Tropical Diseases

“Sera were screened for anti-dengue virus IgG and IgM antibodies. Risk factors of seropositivity were tested using logistic regression methods with random effects.”

Carrasco DenguePredictive Tools for Severe Dengue Conforming to World Health Organization 2009 Criteria – Luis R. Carrasco – PLOS Neglected Tropical Diseases

“Higher risk of severe dengue (SD) was associated with female gender, lower than normal hematocrit level, abdominal distension, vomiting and fever on admission. “

Infection and host response

Screen shot 2014-07-11 at 03.35PM, Jul 11Development of Fatal Intestinal Inflammation in MyD88 Deficient Mice Co-infected with Helminth and Bacterial Enteropathogens – Libo Su – PLOS Neglected Tropical Diseases

“We found that MyD88 knockout mice co-infected with H. polygyrus and C. rodentium developed more severe intestinal inflammation and elevated mortality compared to the wild-type mice.”‘

Screen shot 2014-07-11 at 04.28PM, Jul 11Distinct Lipid A Moieties Contribute to Pathogen-Induced Site-Specific Vascular Inflammation – Connie Slocum – PLOS Pathogens

“our results point to a pivotal role for activation of the non-canonical inflammasome in P. gingivalis infection and demonstrate that P. gingivalis evades immune detection at TLR4 facilitating chronic inflammation in the vasculature. “

Dengue

Dengue vaccine lancetClinical efficacy and safety of a novel tetravalent dengue vaccine in healthy children in Asia: a phase 3, randomised, observer-masked, placebo-controlled trial – Maria Rosario Capeding – The Lancet

“Our findings show that dengue vaccine is efficacious when given as three injections at months 0, 6, and 12 to children aged 2–14 years in endemic areas in Asia, and has a good safety profile. “

Also see comment: Dengue vaccines: dawning at last? – Annelies Wilder-Smith – The Lancet

Poliovirus

Jacob John polioEffect of a single inactivated poliovirus vaccine dose on intestinal immunity against poliovirus in children previously given oral vaccine: an open-label, randomised controlled trial – Jacob John – The Lancet

“The substantial boost in intestinal immunity conferred by a supplementary dose of IPV given to children younger than 5 years who had previously received OPV shows a potential role for this vaccine in immunisation activities to accelerate eradication and prevent outbreaks of poliomyelitis.”

Also see comment: Polio endgame management: focusing on performance with or without inactivated poliovirus vaccine – Kimberly M Thompson – The Lancet

Microbes in the News

Screen shot 2014-07-11 at 04.28PM, Jul 11 1How Gross Is Your Phone? A Motherboard Science Experiment – Jason Koebler – Motherboard

“All I wanted to do was recreate a relatively simple study I had just written about. Instead, I ended up creating something vaguely dangerous, which mortified the director of a local DIY biology lab. Here’s what happens when you perform experiments on your coworkers.”

Arsenic metabolism

Screen shot 2014-07-11 at 04.29PM, Jul 11Lung tumors in mice induced by “whole-life” inorganic arsenic exposure at human-relevant doses – Michael P. Waalkes – Archives of Toxicology

“Breeder male and female CD1 mice were exposed to 0, 50, 500 or 5,000 ppb arsenic (as sodium arsenite) in the drinking water for 3 weeks prior to breeding, during pregnancy and lactation, and after weaning (at week 3) groups of male and female offspring (initial n = 40) were exposed for up to 2 years.”

Dr. Bik’s Picks

Scorpions are master architects, according to new research – Science Daily

“The burrows made by scorpions follow a very sophisticated design, beginning with a short, vertical entrance shaft that flattened out a few centimeters below the surface into a horizontal platform, new research has found.”

Beach Sand Used To Make A Battery That Lasts Three Times Longer – Douglas Main – Popular Science

“Sink your toes into this: Beach sand can be used to make lithium-ion batteries that last three times longer than current models, according to a study published in the journal Scientific Reports.”

World Now “A Safer Place”, thanks to creation of Potential Pandemic Virus – The Allium

“Yes, I get your point that they could potentially kill millions of people and hospitalise millions more, causing untold human suffering and extraordinary economic damage, but think of all the advantages to the creation of these bugs”.

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Human microbiome, July 8

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Female urinary microbiome, stool microbiome and vaccine responses, and gut microbiome in ulcerative colitis patients.

Urinary tract

The Female Urinary Microbiome: a Comparison of Women with and without Urgency Urinary Incontinence – Meghan M. Pearce – mBio

“In this study, we used 16S rRNA gene sequencing to classify bacterial DNA and expanded quantitative urine culture (EQUC) techniques to isolate live bacteria in urine collected by using a transurethral catheter from women with UUI and, in comparison, a cohort without UUI. “

Gut microbiome

Stool Microbiota and Vaccine Responses of Infants – M. Nazmul Huda – Pediatrics

“Bifidobacterium predominance may enhance thymic development and responses to both oral and parenteral vaccines early in infancy”

Novel Gut-Based Pharmacology of Metformin in Patients with Type 2 Diabetes Mellitus – Antonella Napolitano – PLOS ONE

“Microbiota abundance of the phylum Firmicutes was positively correlated with changes in cholic acid and conjugates, while Bacteroidetes abundance was negatively correlated.”

This one was already published online in September 2013 but it came out in print this week : Commentary: Roseburia hominis: a novel guilty player in ulcerative colitis pathogenesis – Herbert Tilg – Gut

“In recent years evidence was accumulating that the gut microbiota and its manipulation might constitute one of those relevant ‘environmental’ factors. “

A decrease of the butyrate-producing species Roseburia hominis and Faecalibacterium prausnitzii defines dysbiosis in patients with ulcerative colitis – Kathleen Machiels – Gut

“The composition of the fecal microbiota of UC patients differs from that of healthy individuals: we found a reduction in R hominis and F prausnitzii, both well-known butyrate-producing bacteria of the Firmicutes phylum. “

Pregnancy and birth

Direct Evidence for the Presence of Human Milk Oligosaccharides in the Circulation of Breastfed Infants – Karen C. Goehring – PLOS ONE

“At least some ingested HMOs are absorbed intact into the circulation and excreted in the urine and their concentrations in these fluids correlate with levels of the corresponding mother’s milk”

Commentary: More than a gut feeling: predicting surgical necrotising enterocolitis – Jörn-Hendrik Weitkamp – Gut

“The paper by Sylvester et al 8 describes a new non-invasive approach of combining clinical data and selected urine peptide biomarkers to develop an algorithm to predict progression of suspected medical NEC to surgical disease. “

refers to: A novel urine peptide biomarker-based algorithm for the prognosis of necrotising enterocolitis in human infants – Karl G Sylvester – Gut

“Ensemble modelling combining clinical parameters with biomarker analysis dramatically improves our ability to identify the population at risk for developing progressive NEC.”

Animal models

Host Responses to the Pathogen Mycobacterium avium subsp. paratuberculosis and Beneficial Microbes Exhibit Host Sex Specificity – Enusha Karunasena – Applied and Environmental Microbiology

“The differences observed suggest that male and female gut tissues and microbiota respond to newly introduced microorganisms differently and that gut-associated microorganisms with host immune system responses and metabolic activity are supported by biology distinct to the host sex.”

General human microbiome

Phylogenetics and the human microbiome – Frederick A Matsen IV – Submitted to Systematic Biology

“In this paper I review the field and its methods from the perspective of a phylogeneticist, as well as describing current challenges for phylogenetics coming from this type of work.”

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Human microbiome, July 7

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Phages and CRISPRs in human mouth, new metagenomes from MetaHit, and vaginal microbiota.

General microbiome

Journal Nurse PractionersReview: An Overview of the Microbiome and the Effects of Antibiotics – Hillary Taggart – The Journal for Nurse Practitioners

“This review provides a basic introduction of what the microbiome is and how it plays a role in obesity, gastrointestinal, immune, and mental health, including a brief mention of implications for the pediatric population.”

Oral microbiome

Screen shot 2014-07-07 at 01.54PM, Jul 07Characterization of bacteriophage communities and CRISPR profiles from dental plaque – Mayuri Naidu (with David Pride) – BMC Microbiology

“We sampled the saliva and dental plaque from 4 healthy human subjects to determine whether plaque was populated by viral communities, and whether there were differences in viral communities specific to subject or sample type.”

Gut microbiome

Screen shot 2014-07-07 at 01.45PM, Jul 07 1An integrated catalog of reference genes in the human gut microbiome – Junhua Li – Nature Biotechnology

“Here we combined 249 newly sequenced samples of the Metagenomics of the Human Intestinal Tract (MetaHit) project with 1,018 previously sequenced samples to create a cohort from three continents that is at least threefold larger than cohorts used for previous gene catalogs. “

Screen shot 2014-07-07 at 01.45PM, Jul 07Identification and assembly of genomes and genetic elements in complex metagenomic samples without using reference genomes – H Bjørn Nielsen (and 142 other authors) – Nature Biotechnology

“Here we present a method, based on binning co-abundant genes across a series of metagenomic samples, that enables comprehensive discovery of new microbial organisms, viruses and co-inherited genetic entities and aids assembly of microbial genomes without the need for reference sequences.”

Screen shot 2014-07-07 at 01.47PM, Jul 07Commensal microbial regulation of natural killer T cells at the frontiers of the mucosal immune system – Sebastian Zeissig, Richard S. Blumberg – FEBS Letters

“Here, we outline the mechanisms of bidirectional cross-talk between the microbiota and CD1d-restricted NKT cells and discuss how a perturbation of these processes can contribute to the pathogenesis of immune-mediated disorders at mucosal surfaces.”

Screen shot 2014-07-07 at 01.48PM, Jul 07Review/Book chapter Gastrointestinal microbiota – Katherine Stephens – Advanced Nutrition and Dietetics in Gastroenterology

“This chapter summarizes the functions of the human gastrointestinal tract. A main function of the GI microbiota is modulation of the immune system. The chapter focues on the factors influencing composition of the microbiota.”

Pathogens journalPerturbation of the Human Microbiome as a Contributor to Inflammatory Bowel Disease – Bayan Missaghi – Pathogens

“This review presents an outline of the loss of a normal microbiome as an etiology of immune dysregulation and IBD pathogenesis initiation. “

Screen shot 2014-07-07 at 01.49PM, Jul 07 137 People Want to Peer Inside Your Poop…You Know, for Science – Angus Chen – Discover Magazine

“Rob Knight, a microbiologist at the University of Colorado, Boulder, and his colleagues want poop from every person in America.”

Mediterranean Diet and Health: Food Effects on Gut Microbiota and Disease Control
Federica Del Chierico – International Journal of Molecular Sciences

“For this purpose, we present a study proposal relying on the generation of individual gut microbiota maps from MD-aware children/adolescents. “

Respiratory microbiome

Screen shot 2014-07-07 at 02.02PM, Jul 07Evidence that intraspecific trait variation among nasal bacteria shapes the distribution of Staphylococcus aureus – Ben Libberton – Infection and Immunity

“We characterised S. aureus growth inhibition by the culturable bacterial aerobe consortia of 60 nasal microbiomes, revealing intraspecific variation in growth inhibition and that inhibitory isolates clustered within communities that were culture-negative for S. aureus. “

Vaginal microbiome

Screen shot 2014-07-07 at 01.53PM, Jul 07Characterization of the vaginal microbiota of healthy Canadian women through the menstrual cycle – Bonnie Chaban – Microbiome

“Polymerase chain reaction (PCR) was performed to amplify the universal target region of the cpn60 gene and generate amplicons representative of the microbial community. Amplicons were pyrosequenced, assembled into operational taxonomic units, and analyzed. “

Pregnancy

The effects of designation and volume of neonatal care on mortality and morbidity outcomes of very preterm infants in England: retrospective population-based cohort study – SI Watson – BMJ Open

“High-volume neonatal care provided at the hospital of birth may protect against in-hospital mortality in very preterm infants. “

Understanding the Complexity of the Immune System during Pregnancy – Karen Racicot – American Journal of Reproductive Immunology

“In this review, we discuss our present understanding of the ‘immunity of pregnancy’ in the context of the response to cervical and placental infections and how these responses affect both the mother and the fetus.”

 

Animal models of human microbiota or disease

Screen Shot 2014-07-07 at 11.00.33 PMGalacto‐oligosaccharides attenuate renal injury with microbiota modification – Satoshi U. Furuse – Physiological Reports

“The microbiota analysis indicated that GOS significantly increased three bacterial families and decreased five families in the Nx rats. “

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General microbiome digest, July 1

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Diet and gut microbiome (again), Campylobacter in chicken is not a commensal, microbiomes of fish, insects, corals, plant, and hospitals, and women in science.

Human gut microbiome

Screen shot 2014-07-01 at 06.07PM, Jul 01Correlation network analysis reveals relationships between diet-induced changes in human gut microbiota and metabolic health – T Kelder – Nutrition & Diabetes

“We assessed fecal microbiota composition and host response patterns of metabolic and inflammatory markers in 10 apparently healthy men subjected to a high-fat high-caloric diet (HFHC, 1300 kcal/day extra) for 4 weeks. “

Pregnancy and birth

Screen shot 2014-07-01 at 06.08PM, Jul 01 1Gestational Age and Age at Sampling Influence Metabolic Profiles in Premature Infants
Reese H. Clark – Pediatrics

“Metabolic profiles (15 amino acids and 35 acylcarnitines) were obtained by using standard newborn techniques on infants born between 23 and 31 completed weeks of gestation.”

Screen shot 2014-07-01 at 06.08PM, Jul 01Non-invasive analysis of intestinal development in preterm and term infants using RNA-Sequencing – Jason M. Knight – Nature Scientific Reports

“we have developed a novel, noninvasive, molecular approach that utilizes next generation RNA sequencing on stool samples containing intact epithelial cells for the purpose of quantifying intestinal gene expression.”

Screen shot 2014-07-01 at 06.09PM, Jul 01Cesarean Section and Rate of Subsequent Stillbirth, Miscarriage, and Ectopic Pregnancy: A Danish Register-Based Cohort Study – Sinéad M. O’Neill – PLOS Medicine

“This study found that cesarean section is associated with a small increased rate of subsequent stillbirth and ectopic pregnancy.”

Bird microbiome

Screen shot 2014-07-01 at 06.10PM, Jul 01Campylobacter jejuni Is Not Merely a Commensal in Commercial Broiler Chickens and Affects Bird Welfare – Suzanne Humphrey – mBio

“Through experimental infection of four commercial breeds of broiler chickens, we show that breed has a significant effect on C. jejuni infection and the immune response of the animals, although these factors have limited impact on the number of bacteria in chicken ceca. “

Fish microbiome

Screen shot 2014-07-01 at 06.10PM, Jul 01 1Quorum quenching bacteria Bacillus sp. QSI-1 protect zebrafish (Danio rerio) from Aeromonas hydrophila infection – Weihua Chu – Nature Scientific Reports

“In this study, the effect of Bacillus sp. QSI-1 as an efficient quorum quencher on virulence factors production and biofilm formation of fish pathogen Aeromonas hydrophila was investigated. ”

Insect microbiome

Screen shot 2014-07-01 at 06.11PM, Jul 01Evolutionary origin of insect–Wolbachia nutritional mutualism – Naruo Nikoh – PNAS

“In the bedbug’s Wolbachia genome, we identified a gene cluster encoding the complete synthetic pathway for biotin (vitamin B7), which is not present in other Wolbachia genomes and is presumably acquired via lateral transfer from a coinfecting endosymbiont. “

Corals and sponges microbiome

Screen shot 2014-07-01 at 06.12PM, Jul 01Local genomic adaptation of coral reef-associated microbiomes to gradients of natural variability and anthropogenic stressors – Linda W. Kelly – PNAS

“The present study investigated the community structure and metabolic potential of microbes inhabiting coral reefs located across an extensive area in the central Pacific. “

Plant microbiome

Screen shot 2014-07-01 at 06.13PM, Jul 01The role of sulfur and phosphorus mobilizing bacteria in biochar induced growth promotion of Lolium perenne – A Fox – FEMS Microbiology Ecology

“16S rRNA gene based rhizobacteria community analysis revealed a significant biochar treatment effect. Abundance of nematodes feeding on bacteria was also significantly increased in the biochar treatments.”

Functional diversification within bacterial lineages promotes wide functional overlapping between taxonomic groups in a Mediterranean soil forest – J Curiel Yuste – FEMS Microbiology Ecology

“We investigated the relationship between taxonomy and functioning of soil bacterial communities in soils from a Mediterranean Holm-oak forest using a high throughput DNA pyrosequencing technique. “

Soil, sewage and sludge microbiome

Screen shot 2014-07-01 at 06.15PM, Jul 01Response of soil-associated microbial communities to intrusion of coal mine-derived acid mine drainage – Justin S Brantner and John M Senko – Environmental Science & Technology

” Evaluation of pyrosequencing-derived 16S rRNA gene sequences recovered from incubations revealed the development of microbial community characteristics that were similar to those of the mature iron mound sediment. “

Transformation Products and Human Metabolites of Triclocarban and Triclosan in Sewage Sludge Across the United States – Benny F. G. Pycke – Environmental Science & Technology

“Here, we report on the levels of eight transformation products, human metabolites, and manufacturing byproducts of TCC and TCS in raw and treated sewage sludge.”

Built Environment Microbiome

Screen shot 2014-07-01 at 06.14PM, Jul 01Rethinking Sterile: The Hospital Microbiome – Carrie Arnold – Environ Health Perspect

“Gilbert, an environmental microbiologist at Argonne National Laboratory, and his platoon of graduate students, postdocs, and research assistants descended on the hospital several times each day, even before it opened to the public. Armed with cotton swabs, they focused their efforts on the floors devoted to surgery and oncology. “

Bioinformatics

Screen shot 2014-07-01 at 06.15PM, Jul 01 1A cloud-compatible bioinformatics pipeline for ultrarapid pathogen identification from next-generation sequencing of clinical samples – Samia N. Naccache – Genome Research

“Here we describe SURPI (“sequence-based ultrarapid pathogen identification”), a computational pipeline for pathogen identification from complex metagenomic NGS data generated from clinical samples, and demonstrate use of the pipeline in the analysis of 237 clinical samples comprising more than 1.1 billion sequences. “

Metagenomics

Metagenomic scaffolds enable combinatorial lignin transformation
Cameron R. Strachan – PNAS

“In this study, we devised a previously unidentified biosensor responsive to lignin transformation products. We used this biosensor in a functional screen to recover metagenomic scaffolds sourced from coal bed bacterial communities. “

Arsenic metabolism

Sealing rice field boundaries in Bangladesh: a pilot study demonstrates reductions in water use, arsenic loading to field soils, and methane emissions from irrigation water – Rebecca B Neumann – Environmental Science & Technology

“Irrigation of rice fields in Bangladesh with arsenic-contaminated and methane-rich groundwater loads arsenic into field soils and releases methane into the atmosphere. We tested the water-savings potential of sealing field bunds (raised boundaries around field edges) as a way to mitigate these negative outcomes.”

Localised Flux-Maxima of Arsenic, Lead and Iron around Root Apices in Flooded Lowland Rice – Paul Nicholas Williams – Environmental Science & Technology

“Here we use new diffusive gradients in thin-film (DGT)/planar optode sandwich sensors deployed in situ on rice roots to demonstrate a new geochemical niche of greatly enhanced As, Pb and Fe(II) mobilization into solution immediately adjacent to the root tips characterized by O2 enrichment and low pH. “

Dengue

Screen shot 2014-07-01 at 06.16PM, Jul 01Baicalin, a metabolite of baicalein with antiviral activity against dengue virus – Ehsan Moghaddam – Nature Scientific Reports

“Here, we examined the anti-DENV properties of baicalin in vitro, and described the inhibitory potentials of baicalin at different steps of DENV-2 (NGC strain) replication.”

Antibiotic resistance

Review: The expression of antibiotic resistance genes in antibiotic-producing bacteria – Stefanie Mak – Molecular Microbiology

“Antibiotic-producing bacteria encode antibiotic resistance genes that protect them from the biologically active molecules that they produce. The expression of these genes needs to occur in a timely manner: either in advance of or concomitantly with biosynthesis. It appears that there have been at least two general solutions to this problem. “

General microbiology

Screen shot 2014-07-01 at 06.20PM, Jul 01Bacterial sugar utilization gives rise to distinct single-cell behaviors – Taliman Afroz – Molecular Microbiology

“Here, we performed single-cell analyses to probe the behavior of representative pathways in the model bacterium Escherichia coli. “

Identification of essential Alphaproteobacterial genes reveals operational variability in conserved developmental and cell cycle systems – Patrick D. Curtis and Yves V. Brun – Molecular Microbiology

“These results show that while essential cell functions are conserved across varying genetic distance, much of a given organism’s essential gene pool is specific to that organism.”

Science and career

Screen shot 2014-07-01 at 06.22PM, Jul 01Elite male faculty in the life sciences employ fewer women – Jason M. Sheltzer and Joan C. Smith – PNAS

“To explore the current causes of women’s underrepresentation in biology, we collected publicly accessible data from university directories and faculty websites about the composition of biology laboratories at leading academic institutions in the United States. “

Screen shot 2014-07-01 at 06.01PM, Jul 01Americans Think We Have the World’s Best Colleges. We Don’t. – Kevin Carey – New York Times

“We see K-12 schools and colleges differently because we’re looking at two different yardsticks: the academic performance of the whole population of students in one case, the research performance of a small number of institutions in the other.”

Dr. Bik’s picks

Screen shot 2014-07-01 at 06.23PM, Jul 01Herbivore diet breadth mediates the cascading effects of carnivores in food webs – Michael S. Singer – PNAS

“Accounting for phylogenetic nonindependence of herbivores and plants, we show for the first time (to our knowledge) that dietary specialization of herbivore species is associated with reduced bird predation across an herbivore phylogeny, and that dietary specialization of herbivores increases the antipredator effects of camouflage and aposematism.”

Screen shot 2014-07-01 at 06.23PM, Jul 01 1Evolution of the ribosome at atomic resolution – Anton S. Petrov – PNAS

“Comparing eukaryotic and prokaryotic ribosomes allows us to identify 3D insertion fingerprints of the expansion segments. Similar fingerprints allow us to analyze the common core and detect ancestral expansion segments within it. “

Plastic mapPlastic debris in the open ocean – Andrés Cózar – PNAS

“In this work, we synthetize data collected across the world to provide a global map and a first-order approximation of the magnitude of the plastic pollution in surface waters of the open ocean.”

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Human microbiome, June 30

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Hypotheses about oral microbiota and disease, effect of rhinovirus infection on nasal microbiome,  the gut microbiome in children with diarrhea in low-income countries, primate vaginal microbiomes, and much more.

Oral microbiome (also see Probiotics and Biofilms in today’s General digest)

Screen Shot 2014-06-30 at 11.18.32 PMHistorical and contemporary hypotheses on the development of oral diseases: are we there yet? – Bob T. Rosier – Frontiers in Cellular and Infection Microbiology

“In this comprehensive review, we describe how these different hypotheses, and the ideas around them, arose and test their current applicability to the understanding of the development of oral disease. Finally, we conclude that an all-encompassing ecological hypothesis explaining the shifts from health to disease is still lacking.”

PeriodontitisThe inflammophilic character of the periodontitis-associated microbiota – George Hajishengallis – Molecular Oral Microbiology

“This Review discusses evidence that periodontitis-associated communities are ‘inflammo-philic’ (= loving or attracted to inflammation) in that they have evolved to not only endure inflammation but also to take advantage of it. “

Respiratory microbiome

Screen Shot 2014-06-30 at 11.19.43 PMCharacterization of the nasopharyngeal microbiota in health and during rhinovirus challenge – Allen EK – Microbiome

“Rhinovirus illnesses were induced by self-inoculation using the finger to nose or eye natural transmission route in ten otherwise healthy young adults.”

Gut microbiome

Screen Shot 2014-06-30 at 11.20.28 PMDiarrhea in young children from low-income countries leads to large-scale alterations in intestinal microbiota composition – Mihai Pop – Genome Biology

“We use high throughput 16S rRNA gene sequencing to compare fecal microbiota composition in children under five years of age who have been diagnosed with moderate to severe diarrhea (MSD) with the microbiota from diarrhea-free controls. “

Structure of the gut microbiome following colonization with human feces determines colonic tumor burden – Baxter NT – Microbiome

“We transplanted fecal microbiota from three CRC patients and three healthy individuals into germ-free mice, resulting in six structurally distinct microbial communities. Subjecting these mice to a chemically induced model of CRC resulted in different levels of tumorigenesis between mice. “

Commensal bacteria directly suppress in vitro degranulation of mast cells in a MyD88-independent manner – Kazumi Kasakura – Bioscience, Biotechnology, and Biochemistry

“Here, we show that heat-killed commensal bacteria suppressed degranulation of mast cells in vitro in a MyD88-independent manner.”

Screen Shot 2014-06-30 at 11.21.29 PMCo-occurrence of driver and passenger bacteria in human colorectal cancer
Jiawei Geng – Gut Pathogens

“Building on the driver-passenger model, we used 454 pyrosequencing of bacterial 16S rRNA genes associated with 10 normal, 10 adenoma, and 8 tumor biopsy samples, and found 7 potential driver bacterial genera and 12 potential passenger bacterial genera (7 being pro-inflammatory and 5 anti-inflammatory). “

Review: Intestinal Microbiota and the Efficacy of Fecal Microbiota Transplantation in Gastrointestinal Disease – Olga Aroniadis – Gastroenterology & Hepatology

“The published revelations about the human microbiome are bringing the strength of science to clinical observation and enhancing the understanding of not only disease but also how much of a person’s daily function and health depends on the microorganisms living in intimate relationship with each cell in the body.”

Screen Shot 2014-06-30 at 11.22.43 PMDietary Intervention with Yoghurt, Synbiotic Yogurt or Traditional Fermented Sobya: Bio-Potency among Male Adolescents Using Five Bio-Markers of Relevance to Colonic Metabolic Activities – Laila Hussein – Food and Nutrition Sciences

“The mean fecal total lactobacilli counts increased (P < 0.05) three weeks after daily consumption of the three fermented supplements (P < 0.05), when compared to the pre-intervention levels. Similar trends were observed for genus bifidobacterium. On the contrary, enterobacteraceae counts were reduced in all the three groups consuming fermented supplements.”

Vaginal microbiome (also see pregnancy)

Screen Shot 2014-06-30 at 11.23.32 PMPrimate vaginal microbiomes exhibit species specificity without universal Lactobacillus dominance – Suleyman Yildirim – ISME J (uncorrected proof, link to Chapman Research)

“Our results indicated that all primates exhibited host-specific vaginal microbiota and that humans were distinct from other primates in both microbiome composition and extent of diversity”

Skin microbiome

New Molecular Techniques to Study the Skin Microbiota of Diabetic Foot Ulcers
Jean-Philippe Lavigne – Advances in Wound Care

“Molecular tools have better documented the composition and organization of the skin flora. Further advances are required to elucidate which among the many bacteria in the DFU flora are likely to be pathogens, rather than colonizers.”

General human microbiome 

Shrinkage of the human core microbiome and a proposal for launching microbiome biobanks – Abolfazl Barzegari – Future Microbiology

“This article suggests launching microbiome biobanks for archiving native microbiomes, supervising antibiotic use, probiotic design and native starter production, as well as advertising a revisit to native lifestyles.”

Review: Blowing on Embers: Commensal Microbiota and our Immune System
Darina S. Spasova and Charles D. Surh – Frontiers in Immunology

“This review discusses the recent advances in this field, focusing on the close relationship between the adaptive immune system and commensal microbiota, a constant and abundant source of foreign antigens.”

Microbiome: Second Genome Is Finding Disease Mechanisms, Biomarkers, And Therapeutics – Wayne Koberstein – Life Science Leader

“We now understand that biological processes such as inflammation, barrier function, metabolism, and energy homeostasis are directly linked to our microbiome,” says Peter DiLaura, president and CEO of Second Genome.

Mayo Clinic and Whole Biome Announce Collaboration to Research the Role of the Human Microbiome in Women’s Diseases Using Unique Medical Laboratory Tests – DarkDaily

“This joint research effort will initiate a new field of clinical laboratory diagnostic tests that target the human microbiome”

Prokaryotes versus Eukaryotes: Who is hosting whom? – Guillermo Tellez – Frontiers in Veterinary Science

“Our aim here is to encourage empirical inquiry into the relationship between mutualism and evolutionary diversification between prokaryotes and eukaryotes which encourage us to postulate: Who is hosting whom?”

Animal models of microbiome and disease

Combination of Metagenomics and Culture Based Methods to Study the Interaction Between Ochratoxin A and Gut Microbiota – Mingzhang Guo

“Changes in functional genes of gut microbiota including signal transduction, carbohydrate transport, transposase, amino acid transport system and mismatch repair were observed.”

Functional divergence in gastrointestinal microbiota in physically-separated genetically identical mice – G. B. Rogers – Scientific Reports

“We report significant divergence in both the composition and metabolism of gut microbiota in genetically-identical adult C57BL/6 mice housed in separate controlled units within a single commercial production facility.”

Alteration of Gut Bacteria and Metabolomes After Glucaro-1,4-Lactone Treatment Contributes to the Prevention of Hypercholesterolemia – Baogang Xie – J. Agric. Food Chem

“Colonic flora test results reveal that the quantity of Bifidobacterium and Lactobacillus in the intestines respectively increase by about 1.7- and 4.2-fold in rats treated with 1,4-GL compared with those in the control group. “

Pregnancy and birth

Oral presentation: The evolution of the vaginal microbiome throughout uncomplicated pregnancy in a UK population – M Chandiramani – Arch Dis Child Fetal Neonatal Ed

“Vaginal swabs were collected at time points across gestation (8–12, 20–22, 28–30 and 34–36 weeks) and the postpartum period (6 weeks) from 43 women delivered at term. Resident bacterial communities were determined using the Illumina MiSeq platform generated from bar-coded amplicons of 16S rRNA gene fragments.”

Screen Shot 2014-06-30 at 11.26.14 PMGroup B Streptococcus β-hemolysin/Cytolysin Breaches Maternal-Fetal Barriers to Cause Preterm Birth and Intrauterine Fetal Demise in Vivo – Tara M. Randis – Journal of Infectious Diseases

“We used a new murine model to evaluate the contribution of the pore-forming GBS β-hemolysin/cytolysin (βH/C) to vaginal colonization, ascension, and fetal infection.”

Zinc and copper levels in low birth weight deliveries in Medani Hospital, Sudan –
Abass RM – BMC Research Notes

“Maternal zinc and copper levels, as well as cord copper levels, are lower in LBW newborns than in those with normal weight.”

Effective Biomarkers for Diagnosis of Neonatal Sepsis – Vineet Bhandari – Journal of Pediatric Infectious Diseases

“The diagnostic utility of the following biomarkers seems to be most practical in the early (interleukin [IL]-6, IL-8, tumor necrosis factor-alpha, neutrophil CD64), mid (procalcitonin) and late (C-reactive protein) phases of neonatal sepsis.”

Review: Association of Periodontal Disease and Pre-term Low Birth Weight Infants
Manjusha Varadan, Jaiganesh Ramamurthy – The Journal of Obstetrics and Gynecology of India

“The association of periodontitis as risk factor for pre-term birth has been in extensive research in the past two decades when a number of studies investigated this relationship.”

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Human microbiome, June 25

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Detailed analysis on strain level of oral microbiome and immune cell in term and preterm labor.

Oral microbiome

Screen Shot 2014-06-25 at 10.26.27 PMOligotyping analysis of the human oral microbiome – A. Murat Eren – PNAS

“We used a computational approach that relies on information theory to reanalyze the human oral microbiome. This analysis revealed organisms differing by as little as a single rRNA nucleotide, with dramatically different distributions across habitats or individuals.”

Pregnancy and birth

Screen Shot 2014-06-25 at 10.27.47 PMReview: Immune cells in term and preterm labor – Nardhy Gomez-Lopez – Cellular and Molecular Immunology

“Here, we summarize the role of innate and adaptive immune cells in the physiological or pathological activation of labor. “

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Human and cell phone microbiome, June 24

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The PhoneBiome has finally been characterized. Effect of maltodextrin on gut microbiome, and obesity and risk for preterm birth.

Skin and phone microbiome

Mobile phones carry the personal microbiome of their owners – James F. Meadow – Peer J

“We found that about 22% of the bacterial taxa on participants’ fingers were also present on their own phones, as compared to 17% they shared on average with other people’s phones. “

Gut microbiome

The Metabolizable Energy of Dietary Resistant Maltodextrin Is Variable and Alters Fecal Microbiota Composition in Adult Men – David J. Baer – The Journal of Nutrition

“RM intake was associated with statistically significant increases (P < 0.001) in various operational taxonomic units matching closest to ruminococcus, eubacterium, lachnospiraceae, bacteroides, holdemania, and faecalibacterium, implicating RM in their growth in the gut. “

B cells as a critical node in the microbiota–host immune system network –
Emma Slack – Immunological Reviews

“In this review, we address how B-cell responses to members of the intestinal microbiota form a robust network with mucus, epithelial integrity, follicular helper T cells, innate immunity, and gut-associated lymphoid tissues to maintain host–microbiota mutualism.”

Classification and quantification of bacteriophage taxa in human gut metagenomes – Alison S Waller – ISME Journal 

“Using taxon-specific marker genes, we identified and monitored 20 viral taxa in 252 human gut metagenomic samples, mostly at the level of genera. “

Cesarean delivery and risk of inflammatory bowel disease: a systematic review and meta-analysis – Yi Li – Scandinavian Journal of Gastroenterology

“Results of this meta-analysis support the hypothesis that cesarean delivery was associated with the risk of CD but not of UC. The total rate of cesarean delivery of IBD patients was similar with that of control subjects.

Intestinal microbiota in pathophysiology and management of irritable bowel syndrome – Lee KN – World Journal of Gastroenterology

“…the role of the intestinal microbiota in the pathophysiology and management of IBS is not clear. This review provides the accumulating evidence on it.”

Pregnancy and Birth

Maternal Prepregnancy Body Mass Index and Risk of Spontaneous Preterm Birth – Gary M. Shaw – Paediatric and Perinatal Epidemiology

“Analyses of mothers without hypertension and diabetes, adjusted for age, education, height, and prenatal care initiation, showed obesity categories I–III to be associated with increased risk of spontaneous preterm birth at 20–23 and 24–27 weeks among those of parity 1 in each race/ethnic group.”

and

Obesity before pregnancy linked to earliest preterm births, Stanford/Packard study finds – Erin Digitale – Stanford Medicine News Center

“Women who are obese before they become pregnant face an increased risk of delivering their babies before 28 weeks of pregnancy, a new study of nearly 1 million California births has found.”

Maturation of the enteric mucosal innate immune system during the postnatal period – Marcus Fulde and Mathias W. Hornef – Immunological Reviews

“Here, we discuss both adaptive and developmental mechanisms of the mucosal innate immune system that prevent inappropriate stimulation and facilitate establishment of a stable homeostatic host–microbial interaction after birth.”

Early Infant Nutrition and Metabolic Programming: What Are the Potential Molecular Mechanisms? – Stephanie-May Ruchat – Current Nutrition Reports

“This review will present potential molecular mechanisms through which early postnatal nutrition may influence health and disease programming, focusing on research that used “-omics” approaches (i.e., epigenomics, transcriptomics, proteomics, and metabolomics).”

Oral presentation: Serum beta defensin concentration in the first trimester is related to genotype, and is higher in women who develop PPROM and deliver before 34 weeks – CP James – Arch Dis Child Fetal Neonatal Ed

“Serum hBD2 expression is higher in women who have PPROM and PTB. Women with PPROM and PTB have a distinct innate immune profile evident in their serum in the first trimester, which may provide the basis for a predictive test.”

Animal models of human microbiota and disease

Modulation of gut microbiota during probiotic-mediated attenuation of metabolic syndrome in high fat diet-fed mice – Jingjing Wang – ISME Journal

“Weighted UniFrac principal coordinate analysis based on 454 pyrosequencing of fecal bacterial 16S rRNA genes showed that the probiotic strains shifted the overall structure of the HFD-disrupted gut microbiota toward that of lean mice fed a normal (chow) diet. “

Gut microbiome composition and function in experimental colitis during active disease and treatment-induced remission – Michelle G Rooks – ISME Journal

“Here, we surveyed the gut microbiome of the T-bet−/− Rag2−/− mouse model of colitis during active disease and treatment-induced remission. “

Early-Life Environmental Variation Affects Intestinal Microbiota and Immune Development in New-Born Piglets – Dirkjan Schokker – PLOS ONE

” We observed that the applied antibiotic treatment affected the composition and diversity of gut microbiota and reduced the expression of a large number of immune-related processes. The effect of management procedures on top of the use of an antibiotic was limited.”

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