Publications by authors named "James Fox"

Considerable progress has been made in understanding the roles of Helicobacter pylori in inflammation and gastric cancer; however, far less is known about the roles of enterohepatic Helicobacter species (EHS) in carcinogenesis and their zoonotic or pathogenic potential. We determined the prevalence of EHS infection in a cohort of geriatric rhesus monkeys in which intestinal adenocarcinoma (IAC) is common and investigated the association between EHS infection and IAC. The cohort consisted of 36 animals, 14 of which (age 26-35 years) had IAC.

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Urinary biomarkers may offer a more sensitive and less invasive means to monitor kidney disease than traditional blood chemistry biomarkers such as creatinine. CD1(pcy/pcy) (pcy) mice have a slowly progressive disease phenotype that resembles human autosomal dominant polycystic kidney disease with renal cyst formation and inflammation. Previous reports suggest that dietary protein restriction may slow disease progression in mice and humans with polycystic kidney disease.

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The utility of cryopreserved mouse gametes for reproduction of transgenic mice depends on development of assisted reproductive technologies, including vitrification of unfertilized mouse oocytes. Due to hardening of the zona pellucida, spermatozoa are often unable to penetrate vitrified-warmed (V-W) oocytes. Laser-assisted in vitro fertilization (LAIVF) facilitates fertilization by allowing easier penetration of spermatozoa through a perforation in the zona.

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Objectives: Acupuncture needle manipulation causes mechanical deformation of connective tissue, which in turn results in mechanical stimulation of fibroblasts, with active changes in cell shape and autocrine purinergic signaling. We have previously shown using ultrasound elastography in humans that acupuncture needle manipulation causes measurable movement of tissue up to several centimeters away from the needle. The goal of this study was to quantify the spatial pattern of tissue displacement and deformation (shear strain) in response to acupuncture needling along an intermuscular connective tissue plane compared with needling over the belly of a muscle.

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Recent years have seen a growing consensus that events during one part of an animal's annual cycle can detrimentally affect its future fitness. Notably, migratory species have been shown to commonly display such carry-over effects, facing severe time constraints and physiological stresses that can influence events across seasons. However, to date, no study has examined a full annual cycle to determine when these carry-over effects arise and how long they persist within and across years.

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Higher prevalence of helminth infections in Helicobacter pylori infected children was suggested to potentially lower the life-time risk for gastric adenocarcinoma. In rodent models, helminth co-infection does not reduce Helicobacter-induced inflammation but delays progression of pre-malignant gastric lesions. Because gastric cancer in INS-GAS mice is promoted by intestinal microflora, the impact of Heligmosomoides polygyrus co-infection on H.

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Large individual differences in susceptibility to arsenic-induced diseases are well-documented and frequently associated with different patterns of arsenic metabolism. In this context, the role of the gut microbiome in directly metabolizing arsenic and triggering systemic responses in diverse organs raises the possibility that gut microbiome phenotypes affect the spectrum of metabolized arsenic species. However, it remains unclear how host genetics and the gut microbiome interact to affect the biotransformation of arsenic.

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Doublecortin-like kinase 1 protein (DCLK1) is a gastrointestinal tuft cell marker that has been proposed to identify quiescent and tumor growth-sustaining stem cells. DCLK1⁺ tuft cells are increased in inflammation-induced carcinogenesis; however, the role of these cells within the gastrointestinal epithelium and their potential as cancer-initiating cells are poorly understood. Here, using a BAC-CreERT-dependent genetic lineage-tracing strategy, we determined that a subpopulation of DCLK1⁺ cells is extremely long lived and possesses rare stem cell abilities.

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Campylobacter is a common bacterial enteropathogen that can be detected in stool by culture, enzyme immunoassay (EIA), or PCR. We compared culture for C. jejuni/C.

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Background: The human intestine is host to an enormously complex, diverse, and vast microbial community-the gut microbiota. The gut microbiome plays a profound role in metabolic processing, energy production, immune and cognitive development, epithelial homeostasis, and so forth. However, the composition and diversity of the gut microbiome can be readily affected by external factors, which raises the possibility that exposure to toxic environmental chemicals leads to gut microbiome alteration, or dysbiosis.

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Fish behaviours are often considered to be sensitive endpoints of waterborne contaminants, but little attention has been given to engineered nanomaterials. The present study aimed to determine the locomotor and social behaviours of rainbow trout (Oncorhynchus mykiss) during waterborne exposure to single-walled carbon nanotubes (SWCNTs), and to ascertain the physiological basis for any observed effects. Dispersed stock suspensions of SWCNTs were prepared by stirring in sodium dodecyl sulphate (SDS), an anionic surfactant, on an equal w/w basis.

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Since its discovery in 1982, the global importance of Helicobacter pylori-induced disease, particularly in developing countries, remains high. The use of rodent models, particularly mice, and the unanticipated usefulness of the gerbil to study H. pylori pathogenesis have been used extensively to study the interactions of the host, the pathogen, and the environmental conditions influencing the outcome of persistent H.

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Animal models have greatly enriched our understanding of the molecular mechanisms of numerous types of cancers. Gastric cancer is one of the most common cancers worldwide, with a poor prognosis and high incidence of drug-resistance. However, most inbred strains of mice have proven resistant to gastric carcinogenesis.

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Background: Helicobacter canis has been associated with hepatobiliary and gastrointestinal disease in dogs, cats, and humans. Infection has not been documented in other species.

Materials And Methods: Sheep feces subjected to microaerobic culture.

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Exposure to arsenic affects large human populations worldwide and has been associated with a long list of human diseases, including skin, bladder, lung, and liver cancers, diabetes, and cardiovascular disorders. In addition, there are large individual differences in susceptibility to arsenic-induced diseases, which are frequently associated with different patterns of arsenic metabolism. Several underlying mechanisms, such as genetic polymorphisms and epigenetics, have been proposed, as these factors closely impact the individuals' capacity to metabolize arsenic.

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Corticotropin-releasing factor (CRF) is a 41-amino acid neuropeptide that is involved in stress-related physiology and behavior, including control of the hypothalamic-pituitary-adrenal (HPA) axis. Members of the CRF family of neuropeptides, including urocortin 1 (UCN 1), UCN 2, and UCN 3, bind to the G protein-coupled receptors, CRF type 1 (CRF1) and CRF2 receptors. In addition, CRF binding protein (CRFBP) binds both CRF and UCN 1 and can modulate their activities.

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The draft genome sequences of six Colombian Helicobacter pylori strains are presented. These strains were isolated from patients from regions of high and low gastric cancer risk in Colombia and were characterized by multilocus sequence typing. The data provide insights into differences between H.

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A role for microbes has been suspected in prostate cancer but difficult to confirm in human patients. We show here that a gastrointestinal (GI) tract bacterial infection is sufficient to enhance prostate intraepithelial neoplasia (PIN) and microinvasive carcinoma in a mouse model. We found that animals with a genetic predilection for dysregulation of wnt signaling, Apc (Min/+) mutant mice, were significantly susceptible to prostate cancer in an inflammation-dependent manner following infection with Helicobacter hepaticus.

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The discovery of Helicobacter pylori overturned the conventional dogma that the stomach was a sterile organ and that pH values<4 were capable of sterilizing the stomach. H. pylori are an etiological agent associated with gastritis, hypochlorhydria, duodenal ulcers, and gastric cancer.

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The mouse pathobiont Helicobacter hepaticus can induce typhlocolitis in interleukin-10-deficient mice, and H. hepaticus infection of immunodeficient mice is widely used as a model to study the role of pathogens and commensal bacteria in the pathogenesis of inflammatory bowel disease. C57BL/6J Il10(-/-) mice kept under specific pathogen-free conditions in two different facilities (MHH and MIT), displayed strong differences with respect to their susceptibilities to H.

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Colonization by Helicobacter species is commonly noted in many mammals. These infections often remain unrecognized, but can cause severe health complications or more subtle host immune perturbations. The aim of this study was to isolate and characterize putative novel Helicobacter spp.

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Background And Aims: Cholesterol gallstone disease is a complex process involving both genetic and environmental variables. No information exists regarding what role if any the indigenous gastrointestinal microbiota may play in cholesterol gallstone pathogenesis and whether variations in the microbiota can alter cholesterol gallstone prevalence rates.

Methods: Genetically related substrains (BALB/cJ and BALB/cJBomTac) and (BALB/AnNTac and BALB/cByJ) of mice obtained from different vendors were compared for cholesterol gallstone prevalence after being fed a lithogenic diet for 8 weeks.

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