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The incidence of esophageal adenocarcinoma (EA) has drastically increased in the United States since 1970s for unclear reasons. We hypothesized that the widespread usage of antibiotics has increased the procarcinogenic potential of the orodigestive microbiota along the sequence of gastroesophageal reflux (GR), Barrett's esophagus (BE) and EA phenotypes. This case control study included normal controls (NC) and three disease phenotypes GR, BE and EA. Microbiota in the mouth, esophagus, and stomach, and rectum were analyzed using 16S rRNA gene sequencing. Overall, we discovered 44 significant pairwise differences in abundance of microbial taxa between the four phenotypes, with 12 differences in the mouth, 21 in the esophagus, two in the stomach, and nine in the rectum. Along the GR→BE→EA sequence, oral and esophageal microbiota were more diversified, the dominant genus Streptococcus was progressively depleted while six other genera Atopobium, Actinomyces, Veillonella, Ralstonia, Burkholderia and Lautropia progressively enriched. In NC, Streptococcus appeared to control populations of other genera in the foregut via numerous negative and positive connections, while in disease states, the rich network was markedly simplified. Inferred gene functional content showed a progressive enrichment through the stages of EA development in genes encoding antibiotic resistance, ligands of Toll‐like and NOD‐like receptors, nitrate‐nitrite‐nitric oxide pathway and acetaldehyde metabolism. The orodigestive microbiota is in a progressive dysbiotic state along the GR‐BE‐EA sequence. The increasing dysbiosis and antibiotic and procarcinogenic genes in the disease states warrants further study to define their roles in EA pathogenesis. [ABSTRACT FROM AUTHOR]

Abstract: Hirsch-type indices are not only used for the evaluation of individual scientists but also for institutional evaluation. In particular, Prathap''s suggestion, using the pair of h-indices (h 1–h 2) seems a promising approach. This paper discusses these h-indices, incorporating moreover a Molinari correction for size. We provide a theoretical framework and provide practical examples in the field of HIV infection and therapy. It is shown that the National Cancer Institute (NCI, USA) and Harvard University are the leading institutes in this field (in the world). If, however, size is controlled according to the Molinari approach, the National Institute of Allergy and Infectious Diseases (NIAID, USA) becomes the leader. In addition, we provide a new structural index: the ratio h 2/h 1. It is suggested that this ratio indicator is related to the stability of the research performed at an institute or university. The term stability is used here in the sense of not depending on a small group of scientists that could easily move to another university or institute. [Copyright &y& Elsevier]

Background & Aims: Gastroesophageal reflux causes inflammation and intestinal metaplasia and its downstream sequelum adenocarcinoma in the distal esophagus. The incidence of esophageal adenocarcinoma has increased approximately 6-fold in the United States since the 1970s, accompanied with a significant increase in the prevalence of gastroesophageal reflux disease (GERD). Despite extensive epidemiologic study, the cause for GERD and the unexpected increases remain unexplainable. Microbes are among the environmental factors that may contribute to the etiology of GERD, but very little research has been done on the esophageal microbiome, particularly in its relation to GERD. This is the first comprehensive reported correlation between a change in the esophageal microbiome and esophageal diseases. Methods: Biopsy samples of the distal esophagus were collected from 34 patients. Host phenotypes were histologically defined as normal, esophagitis, or Barrett''s esophagus (intestinal metaplasia). Microbiomes from the biopsy samples were analyzed by bacterial 16S ribosomal RNA gene survey and classified into types using unsupervised cluster analysis and phenotype-guided analyses. Independence between host phenotypes and microbiome types were analyzed by Fisher exact test. Results: Esophageal microbiomes can be classified into 2 types. The type I microbiome was dominated by the genus Streptococcus and concentrated in the phenotypically normal esophagus. Conversely, the type II microbiome contained a greater proportion of gram-negative anaerobes/microaerophiles and primarily correlated with esophagitis (odds ratio, 15.4) and Barrett''s esophagus (odds ratio, 16.5). Conclusions: In the human distal esophagus, inflammation and intestinal metaplasia are associated with global alteration of the microbiome. These findings raise the issue of a possible role for dysbiosis in the pathogenesis of reflux-related disorders. [Copyright &y& Elsevier]

The use of depot medroxyprogesterone acetate (DMPA), a 3-monthly injectable hormonal contraceptive, is associated with an increased risk of HIV acquisition possibly through alteration of the vaginal microbiome. In this longitudinal interventional study, we investigated the impact of DMPA administration on the vaginal microbiome in Hispanic White and Black women at the baseline (visit 1), 1 month (visit 2), and 3 months (visit 3) following DMPA treatment by using 16S rRNA gene sequencing. No significant changes in the vaginal microbiome were observed after DMPA treatment when Hispanic White and Black women were analysed as a combined group. However, DMPA treatment enriched total vaginosis-associated bacteria (VNAB) and Prevotella at visit 2, and simplified the correlational network in the vaginal microbiome in Black women, while increasing the network size in Hispanic White women. The microbiome in Black women became more diversified and contained more VNAB than Hispanic White women after DMPA treatment. While the Firmicutes to Bacteroidetes (F/B) ratio and Lactobacillus to Prevotella (L/P) ratio were comparable between Black and Hispanic White women at visit 1, both ratios were lower in Black women than in Hispanic White women at visit 2. In conclusion, DMPA treatment altered the community network and enriched VNAB in Black women but not in Hispanic White women. The Lactobacillus deficiency and enrichment of VNAB may contribute to the increased risk of HIV acquisition in Black women. Future studies on the impact of racial differences on the risk of HIV acquisition will offer insights into developing effective strategies for HIV prevention. Abbreviations: DMPA: depot medroxyprogesterone acetate; PCR: polymerase chain reaction; OTU: operational taxonomic unit; STI: sexually transmitted infections; VNAB: vaginosis-associated bacteria.

Background: Dysbiosis of the oral microbiome can lead to local oral disease and potentially to cancers of the head, neck, and digestive tract. However, little is known regarding exogenous factors contributing to such microbial imbalance., Results: We examined the impact of alcohol consumption on the oral microbiome in a cross-sectional study of 1044 US adults. Bacterial 16S rRNA genes from oral wash samples were amplified, sequenced, and assigned to bacterial taxa. We tested the association of alcohol drinking level (non-drinker, moderate drinker, or heavy drinker) and type (liquor, beer, or wine) with overall microbial composition and individual taxon abundance. The diversity of oral microbiota and overall bacterial profiles differed between heavy drinkers and non-drinkers (α-diversity richness p = 0.0059 and β-diversity unweighted UniFrac p = 0.0036), and abundance of commensal order Lactobacillales tends to be decreased with higher alcohol consumption (fold changes = 0.89 and 0.94 for heavy and moderate drinkers, p trend = 0.005 [q = 0.064]). Additionally, certain genera were enriched in subjects with higher alcohol consumption, including Actinomyces, Leptotrichia, Cardiobacterium, and Neisseria; some of these genera contain oral pathogens, while Neisseria can synthesize the human carcinogen acetaldehyde from ethanol. Wine drinkers may differ from non-drinkers in microbial diversity and profiles (α-diversity richness p = 0.048 and β-diversity unweighted UniFrac p = 0.059) after controlling for drinking amount, while liquor and beer drinkers did not. All significant differences between drinkers and non-drinkers remained after exclusion of current smokers., Conclusions: Our results, from a large human study of alcohol consumption and the oral microbiome, indicate that alcohol consumption, and heavy drinking in particular, may influence the oral microbiome composition. These findings may have implications for better understanding the potential role that oral bacteria play in alcohol-related diseases.