Publications by authors named "Richard Peek"

Objective: Polygenic risk scores (PRS) for diverticular disease must be evaluated in diverse cohorts. We sought to explore shared genetic predisposition across the phenome and to assess risk stratification in individuals genetically similar to European, African and Admixed-American reference samples.

Methods: A 44-variant PRS was applied to the Research Program.

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Gastric cancer is the fifth most common cancer and the fifth leading cause of cancer deaths worldwide. Chronic infection by the bacterium is the most prominent gastric cancer risk factor, but only 1-3% of infected individuals will develop gastric cancer. Cigarette smoking is another independent gastric cancer risk factor, and infected smokers are at a 2-11-fold increased risk of gastric cancer development, but the direct impacts of cigarette smoke on pathogenesis remain unknown.

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Helicobacter pylori is a Gram-negative pathogen that colonizes the stomach, induces inflammation, and drives pathological changes in the stomach tissue, including gastric cancer. As the principal cytokine produced by Th17 cells, IL-17 mediates protective immunity against pathogens by inducing the activation and mobilization of neutrophils. Whereas IL-17A is largely produced by lymphocytes, the IL-17 receptor is expressed in epithelial cells, fibroblasts, and hematopoietic cells.

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Observational evidence suggests that human milk oligosaccharides (HMOs) promote the growth of commensal bacteria in early life and adulthood. However, the mechanisms by which HMOs benefit health through modulation of gut microbial homeostasis remain largely unknown. 2'-fucosyllactose (2'-FL) is the most abundant oligosaccharide in human milk and contributes to the essential health benefits associated with human milk consumption.

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The human pathogen Helicobacter pylori is the strongest known risk factor for gastric disease and cancer, and gastric cancer remains a leading cause of cancer-related death across the globe. Carcinogenic mechanisms associated with H. pylori are multifactorial and are driven by bacterial virulence constituents, host immune responses, environmental factors such as iron and salt, and the microbiota.

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infects half of the world population and is the leading cause of gastric cancer. We previously demonstrated that gastric cancer risk is associated with gastric microbiota. Specifically, gastric urease-positive and had contrasting effects on -associated gastric pathology and immune responses in germ-free INS-GAS mice.

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-induced inflammation is the strongest known risk factor for gastric adenocarcinoma. Hypoxia-inducible factor-1 (HIF-1α) is a key transcriptional regulator of immunity and carcinogenesis. To examine the role of this mediator within the context of -induced injury, we first demonstrated that HIF-1α levels were significantly increased in parallel with the severity of gastric lesions in humans.

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Article Synopsis
  • Metabolic reprogramming is crucial for macrophage functions like fighting bacteria and producing cytokines, with BRD4 playing a significant role in these processes during infections like Helicobacter pylori.
  • In experiments with macrophages from mice lacking BRD4, it was found that BRD4 deficiency impaired the glycolysis process necessary for combating H pylori and resulted in lower nitric oxide production for bacterial killing.
  • The study concludes that BRD4 not only regulates glycolysis in macrophages but also enhances their ability to fight infections by stabilizing messenger RNA needed for nitric oxide production, thus highlighting its importance in the immune response.
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Several probiotic-derived factors have been identified as effectors of probiotics for exerting beneficial effects on the host. However, there is a paucity of studies to elucidate mechanisms of their functions. p40, a secretory protein, is originally isolated from a probiotic bacterium, GG.

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Introduction: Bile acids have been implicated in gastric carcinogenesis. We hypothesized that bile acid sequestrant medication (BAM) use is associated with a lower gastric cancer (GC) incidence.

Methods: We assembled a cohort of veterans receiving longitudinal care within the Veterans Health Administration between 2000 and 2020 who completed testing for Helicobacterpylori .

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Background & Aims: There are no contemporary large-scale studies evaluating the burden of Helicobacter pylori in the United States according to detailed demographics. The primary objective was to evaluate H pylori positivity in a large national healthcare system according to individual demographics and geography.

Methods: We conducted a nationwide retrospective analysis of adults in the Veterans Health Administration who completed H pylori testing between 1999 and 2018.

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Helicobacter pylori infection causes chronic gastritis, which can progress to severe gastroduodenal pathologies, including peptic ulcer, gastric cancer and gastric mucosa-associated lymphoid tissue lymphoma. H. pylori is usually transmitted in childhood and persists for life if untreated.

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Along with infection, the gastric microbiota is hypothesized to modulate stomach cancer risk in susceptible individuals. Whole metagenomic shotgun sequencing (WMS) is a sequencing approach to characterize the microbiome with advantages over traditional culture and 16S rRNA sequencing including identification of bacterial and non-bacterial taxa, species/strain resolution, and functional characterization of the microbiota. In this study, we used WMS to survey the microbiome in extracted DNA from antral gastric biopsy samples from Colombian patients residing in the high-risk gastric cancer town Túquerres ( = 10, -positive = 7) and low-risk town of Tumaco ( = 10, -positive = 6).

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Chronic mucosal pathogens have evolved multiple strategies to manipulate the host immune response; consequently, microbes contribute to the development of >2 million cases of cancer/year. Gastric adenocarcinoma is the fourth leading cause of cancer-related death and confers the highest risk for this disease. Gastric innate immune effectors can either eliminate bacteria or mobilize adaptive immune responses including Toll-like receptors (TLRs), and cytosolic DNA sensor/adaptor proteins (e.

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Helicobacter pylori (H. pylori) is a common gastric pathogen that infects approximately half of the world's population. Infection with H.

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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.

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Objective: An international meeting was organised to develop consensus on (1) the landmarks to define the gastro-oesophageal junction (GOJ), (2) the occurrence and pathophysiological significance of the cardiac gland, (3) the definition of the gastro-oesophageal junctional zone (GOJZ) and (4) the causes of inflammation, metaplasia and neoplasia occurring in the GOJZ.

Design: Clinical questions relevant to the afore-mentioned major issues were drafted for which expert panels formulated relevant statements and textural explanations.A Delphi method using an anonymous system was employed to develop the consensus, the level of which was predefined as ≥80% of agreement.

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Gastric carcinogenesis is mediated by complex interactions among Helicobacter pylori, host, and environmental factors. Here, we demonstrate that H. pylori augmented gastric injury in INS-GAS mice under iron-deficient conditions.

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In populations with similar prevalence of Helicobacter pylori infection, cancer risk can vary dramatically. Changes in composition or structure of bacterial communities in the stomach, either at the time of exposure or over the course of H. pylori infection, may contribute to gastric pathology.

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Background: Mother-to-child transmission of Helicobacter pylori (H. pylori) is the primary source of intrafamilial spread in early childhood in regions of high H. pylori prevalence.

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Background: Helicobacter pylori eradication is associated with reduced gastric cancer and peptic ulcer disease incidence and mortality. Factors influencing patients' experiences surrounding H. pylori diagnosis and management are not well-described.

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Background & Aims: Helicobacter pylori infects approximately 50% of individuals worldwide. Successful H pylori eradication is associated with reduced risk of gastric cancer and peptic ulcer disease, among other conditions. We hypothesized that host genetic determinants, especially those affecting gastric pH, might contribute to eradication therapy failure, particularly when treatment adherence and antibiotic susceptibility are confirmed.

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Helicobacter pylori is a pathogen that confers the highest known risk for gastric cancer. Research directed at understanding the pathogenesis of H. pylori is crucial to identify colonized persons that may subsequently develop neoplasia.

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