12276 results for ""statistically+reactive"+taxa+in+microbial+community"

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• Microbial infections in Multiple Sclerosis Samples

  In this study, we have examined microbial infection in brain tissue from 9 control samples from healthy patients and 10 samples from patients diagnosed with Multiple sclerosis, by Next-generation sequencing NGS using Miseq sequencing platform (Illumina).

  Dataset EGAD00001004085

• The Thrifty Microbiome: The Role of the Gut Microbiota in Obesity in the Amish

  Emerging evidence that the gut microbiota may contribute in important ways to human health and disease has led us and others to hypothesize that both symbiotic and pathological relationships between gut microbes and their host may be key contributors to obesity and the metabolic complications of obesity. Our "Thrifty Microbiome Hypothesis" poses that gut microbiota play a key role in human energy homeostasis. Specifically, constituents of the gut microbial community may introduce a survival advantage to its host in times of nutrient scarcity, promoting positive energy balance by increasing efficiency of nutrient absorption and improving metabolic efficiency and energy storage. However, in the presence of excess nutrients, fat accretion and obesity may result, and in genetically predisposed individuals, increased fat mass may result in preferential abdominal obesity, ectopic fat deposition (liver, muscle), and metabolic complications of obesity (insulin resistance, hypertension, hyperlipidemia). Furthermore, in the presence of excess nutrients, a pathological transition of the gut microbial community may occur, causing leakage of bacterial products into the intestinal lymphatics and portal circulation, thereby inducing an inflammatory state, further aggravating metabolic syndrome traits and accelerating atherosclerosis. This pathological transition and the extent to which antimicrobial leakage occurs and causes inflammatory and other maladaptive sequelae of obesity may also be influenced by host factors, including genetics. In the proposed study, we will directly test the Thrifty Microbiome Hypothesis by performing detailed genomic and functional assessment of gut microbial communities in intensively phenotyped and genotyped human subjects before and after intentional manipulation of the gut microbiome. To address these hypotheses, five specific aims are proposed: (1) enroll three age- and sex-matched groups from the Old Order Amish: (i) 50 obese subjects (BMI > 30 kg/m2) with metabolic syndrome, (ii) 50 obese subjects (BMI > 30 kg/m2) without metabolic syndrome, and (iii) 50 non-obese subjects (BMI < 25 kg/m2) without metabolic syndrome and characterize the architecture of the gut microbiota from the subjects enrolled in this study by high-throughput sequencing of 16S rRNA genes; (2) characterize the gene content (metagenome) to assess the metabolic potential of the gut microbiota in 75 subjects to determine whether particular genes or pathways are correlated with disease phenotype; (3) characterize the transcriptome in 75 subjects to determine whether differences in gene expression in the gut microbiota are correlated with disease phenotype, (4) determine the effect of manipulation of the gut microbiota with antibiotics on energy homeostasis, inflammation markers, and metabolic syndrome traits in 50 obese subjects with metabolic syndrome and (5) study the relationship between gut microbiota and metabolic and cardiovascular disease traits, weight change, and host genomics in 1,000 Amish already characterized for these traits and in whom 500K Affymetrix SNP chips have already been completed. These studies will provide our deepest understanding to date of the role of gut microbes in terms of 'who's there?', 'what are they doing?', and 'how are they influencing host energy homeostasis, obesity and its metabolic complications? PUBLIC HEALTH RELEVANCE: This study aims to unravel the contribution of the bacteria that normally inhabit the human gastrointestinal tract to the development of obesity, and its more severe metabolic consequences including cardiovascular disease, insulin resistance and Type II diabetes. We will take a multidisciplinary approach to study changes in the structure and function of gut microbial communities in three sets of Old Order Amish patients from Lancaster, Pennsylvania: obese patients, obese patients with metabolic syndrome and non-obese individuals. The Old Order Amish are a genetically closed homogeneous Caucasian population of Central European ancestry ideal for genetic studies. These works have the potential to provide new mechanistic insights into the role of gut microflora in obesity and metabolic syndrome, a disease that is responsible for significant morbidity in the adult population, and may ultimately lead to novel approaches for prevention and treatment of this disorder.

  Study phs000258

• Study of the Human Skin Metagenome Associated with Acne

  Studies have emphasized the importance of disease-associated microorganisms in perturbed communities, however, the protective roles of commensals are largely under recognized and poorly understood. Using acne as a model disease, we investigated the determinants of the overall virulence property of the skin microbiota when disease- and health-associated organisms coexist in the community. By ultra-deep metagenomic shotgun sequencing, we revealed higher relative abundances of propionibacteria and Propionibacterium acnes phage in healthy skin. In acne patients, the microbiome composition at the species level and at P. acnes strain level was more diverse than in healthy individuals, with enriched virulence-associated factors and reduced abundance of metabolic synthesis genes. Based on the abundance profiles of the metagenomic elements, we constructed a quantitative prediction model, which classified the clinical states of the host skin with high accuracy in both our study cohort (85%) and an independent sample set (86%). Our results suggest that the balance between metagenomic elements, not the mere presence of disease-associated strains, shapes the overall virulence property of the skin microbiota. This study provides new insights into the microbial mechanism of acne pathogenesis and suggests probiotic and phage therapies as potential acne treatments to modulate the skin microbiota and to maintain skin health.

  Study phs001655

• Fragment ends of circulating microbial DNA as signatures for infectious diseases

  Fragment ends of circulating microbial DNA as signatures for infectious diseases

  Study EGAS00001006321

• Reconstruction of the microbial genomes from the Japanese gut metagenome

  We performed a metagenome shotgun sequencing to identify the microbial features of Japanese.

  Study JGAS000531

• Microbiome-Host Interactions in Oral Squamous Cell Carcinoma: a Metatranscriptomic Exploratory Study

  Oral cancer (predominantly squamous cell carcinoma; OSCC) is the 14th most prevalent malignancy worldwide, accounting for more than 300,000 new cases and 145,000 deaths annually. Despite advances in cancer treatment modalities, OSCC continues to have poor prognosis with 5-year survival rates less than 50%. Although use of tobacco and alcohol consumption constitute the major risk factors, there is emerging evidence for the role of the microbiome in OSCC. However, studies on the association between the microbiome and OSCC has so far focused on compositional analysis and has been largely limited to the bacterial component of the microbiome. The aim of this study is to characterize the transcriptional activity (function) as well as composition of the multi-kingdom microbiome associated with OSCC and correlate it with the gene expression of the host using ultra-deep metatranscriptome sequencing, which will provide new insight into the role of the microbiome in OSCC and the possible mechanisms by which the tumor’s microbial community may influence on its behavior. This project comprises RNA-Seq data from twenty OSCC tumor/normal tissue pairs and twenty tongue scraping samples from healthy controls. However, due to consent constraints, the human sequences from the control data are filtered out.

  Study phs002678

• The Vaginal Microbiome: Disease, Genetics and the Environment

  The vagina is an interactive interface with the environment, and as such is covered by a protective epithelial surface. This surface is colonized by a biofilm consisting of bacteria and other microorganisms, which through a variety of mechanisms serve to protect the host from invasion by pathogens. Alterations in the normal vaginal microflora; i.e., dysbioses, particularly those associated with bacterial vaginosis, the most common disorder of the female reproductive tract, contribute to risk of sexually transmitted infections, infection by HIV, and are associated with increased risk of adverse pregnancy outcomes including but not limited to spontaneous preterm birth. Physiologic alterations in the host (e.g., menopause and pregnancy), which are beginning to be investigated as potential selective conditions for change in the "normal" vaginal flora, and their impact on disease susceptibility and transmission, remain to be more definitively elucidated. The effects of chronically abnormal physiologic states (e.g., diabetes mellitus) on normal vaginal flora have not been well described or studied. Finally, an almost unexplored area of inquiry is the genetic contribution, including race/ethnicity, to the establishment and maintenance of a "normal" vaginal flora, under normal and physiologically altered circumstances. Our research will shed light on how the vaginal microbiome contributes to adverse obstetrical outcomes and sexually transmitted infections in diverse populations. This project addresses the following questions: First: Do the genes of the host contribute to the composition of the vaginal microbiome? We hypothesize that a woman's genetic composition significantly affects the ability of certain commensal, parasitic and pathogenic microbes to colonize and/or infect the genital tract. Thus, we will compare and quantify the microbial populations inhabiting the vaginas of monozygotic and dizygotic twins from the Mid Atlantic Twin Registry, and, in the process, address the question of whether there is a relationship between the microbiomes of the vagina, mouth and GI tract. Second: What changes in the vaginal microbiome are associated with common physiological perturbations or non-infectious pathological states of the host?We hypothesize that "altered" physiologic (pregnancy, menopause) and pathologic (chronic disease, hysterectomy) conditions, or environmental "exposures" (exogenous hormones, antibiotics, chronic immunosuppressant, smoking; douching) can predictably alter the vaginal microenvironment. These alterations will lead to changes in microbial populations within the vagina. Changes in the microbial populations may have impacts, positive or more likely negative, on the spontaneous and future well-being of the affected individual. We are characterizing the effects of these "altered" physiologic and pathologic conditions, and environmental exposures, on the composition of the vaginal microbiome. Finally, we are examining the impact of the important physiological changes incurred during pregnancy on the composition of the microbiome of the female reproductive tract. Third: What changes in the vaginal microbiome are associated with relevant infectious diseases and conditions? We are testing the hypothesis that infectious diseases predictably alter the vaginal microbiome, and that these changes have an impact on the disease susceptibility, process, and outcome. A predilection for bacterial vaginosis, vaginitis, HIV infection, or other sexually transmitted diseases, is likely associated with a women's vaginal microbial composition. Thus, we will characterize samples from women with a variety of these infectious conditions to determine the contribution of their microbiomes to the disease process and susceptibility. We are addressing these questions using a combination of high throughput 'nextgen' sequencing technologies. Early studies were performed using the Roche 454 FLX and the first generation Illumina Genome Analyzer II instruments and more recently employing Illumina MiSeq and HiSeq 2500 and 4000 platforms, installed in the Genomics Core of the Nucleic Acids Research Facilities at VCU. Thus, segments of the 16S rRNA genes are amplified from the complex samples taken from various target sites in and around the vagina of each study participant. These segments are sequenced and subjected to taxonomic classification protocols to identify and quantify the bacterial taxa present in each sample. Additionally, total DNA isolated from these samples are subjected to shotgun sequence analysis to empirically reconstruct the metabolic potential of these microbiomes. Finally, specific bacterial clones are completely sequenced and analyzed to associate the unavoidable strain and isolate diversity with the clinical phenotypes presented.

  Study phs000256

• PhIP-Seq LLD

  Bacteriophage Immunoprecipitation Sequencing (PhIP-Seq) of LLD participants. Libraries and protocol were developed in the Weizmann Institute of Science. Two different libraries were used, containing microbial and other immunological peptides respectively.

  Study EGAS00001006999

• Global Microbiome Conservancy Sequence Data

  The human body is a complex ecosystem, hosting tens of billions of bacteria, primarily in the gut. This community, known as the 'gut microbiome', is vital to human health, affecting functions ranging from metabolism, immunity, and development, to behavior. Conversely, reduced microbiome diversity and other imbalances of the gut community (dysbiosis) are associated with many diseases of the industrialized world, such as metabolic syndrome, asthma, and inflammatory bowel diseases among others. Microbiome-based interventions thus hold the potential to revolutionize our understanding of, and therapeutic approaches to, many aspects of human health and disease. Despite many advances, current understanding of the human microbiome is largely limited to majority ethnic groups in industrialized nations, and does not reflect the full diversity of human commensal microbiota. In addition to the scientific ramifications of minority underrepresentation, there are significant translational and ethical implications as well: first, failing to capture the full diversity of healthy human microbiota may limit our ability to understand and generate effective therapeutics for many microbiome-associated diseases. Second, underrepresented groups are less likely to benefit from microbiome-based medical advances tailored to well-studied populations, propagating healthcare inequities.  Human gut microbial diversity is diminishing around the globe, due to the spread of industrialized diets and lifestyles, which are associated with reduced microbiome biodiversity. The Global Microbiome Conservancy (GMbC) is a non-profit collaboration between scientists and communities around the world that aims to 1) preserve the full biodiversity of the human gut microbiome, 2) characterize its evolution across populations and host lifestyles and 3) investigate its interactions with the human host. We are collecting gut microbiome and human DNA samples from diverse populations around the world, from isolated groups to urbanized populations, to culture and study this essential biodiversity and to preserve it in a living "seed bank" of bacterial isolates as a long-term safeguard against future extinctions. Human genetic data for the samples sequenced in this study can be found in phs002205.

  Study phs002235

• Skin Microbiome in Disease States: Atopic Dermatitis and Immunodeficiency

  The NIH Intramural Skin Microbiome Consortium (NISMC) is a collaboration of investigators with primary expertise in genomics, bioinformatics, large-scale DNA sequencing, dermatology, immunology, allergy, infectious disease, and clinical microbiology. Atopic dermatitis (AD, "eczema") is a chronic relapsing skin disorder that affects ~15% of U.S. children and is associated with $1 billion of medical costs annually. AD is characterized by dry, itchy skin, infiltrated with immune cells. Colonization by Staphylococcus aureus (S. aureus) is ten-fold more common in AD patients and is associated with disease flares. We hypothesize that, in addition to S. aureus, AD may also be associated with additional novel microbes and/or selective shifts of commensal microbes that are relevant to disease progression. The NISMC seeks to define the microbiota that resides in and on the skin and nares of three patient groups, all of whom have eczematous lesions and are currently seen at the NIH Clinical Center: (1) AD patients; (2) Wiskott-Aldrich syndrome (WAS) patients; and (3) Hyper IgE syndrome (HIES) syndrome patients. Examination of the microbiome of patients with WAS or HIES syndromes, both rare immunodeficiencies, will advance our understanding of how an individual's immune system shapes their cutaneous microbial community. We are performing a prospective longitudinal study that follows these groups of patient thorough the cycles of eczema flares, ascertaining clinical data and samples at each stage.

  Study phs000266