89 research outputs found
The Chemtrak Hp Chek Fingerstick Whole Blood Serology Test for the Detection of Helicobacter pylori Infection
To evaluate a new whole blood serology test (Hp Chek; ChemTrak) that detects IgG antibodies to Helicobacter pylori . Methods : The study was conducted at 10 sites within the United States. Patients undergoing upper endoscopy for dyspepsia were recruited for enrollment. Those treated for H. pylori infection within a year of endoscopy and those who had regularly used proton pump inhibitors, bismuth compounds, or antibiotics within a month of endoscopy were not eligible. During endoscopy, specimens were obtained from the corpus and antrum for histological examination, which was performed by a single experienced pathologist. The Hp Chek was tested using whole blood and serum. Serum was also tested with a reference enzyme-linked immunosorbent assay (ELISA) at a centralized location. Test characteristics for the Hp Chek and ELISA were calculated using histology as the “gold standard.”. Results : Two hundred eighty-seven patients (140 women and 147 men; mean age 53 ± 6 yr ) were enrolled. The Hp Chek was easy to perform and yielded results 9 min after inoculation of the test cassette with whole blood or serum. When the Hp Chek used with whole blood was compared with histology as the gold standard, the sensitivity was 88%, specificity 85%, positive predictive value 83%, negative predictive value 90%, and percent agreement 86%. There were no statistically significant differences among the results obtained with the Hp Chek using whole blood, the Hp Chek using serum, or reference ELISA. Conclusions : The Hp Chek whole blood serology test was easy to perform and rapid and yielded performance characteristics comparable to those of a reference ELISA or the Hp Chek used with serum.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75251/1/j.1572-0241.1998.016_c.x.pd
Barrett's esophagus: prevalence–incidence and etiology–origins
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/86957/1/j.1749-6632.2011.06042.x.pd
Helicobacter pylori cag-Pathogenicity Island-Dependent Early Immunological Response Triggers Later Precancerous Gastric Changes in Mongolian Gerbils
Infection with Helicobacter pylori, carrying a functional cag type IV secretion system (cag-T4SS) to inject the Cytotoxin associated antigen (CagA) into gastric cells, is associated with an increased risk for severe gastric diseases in humans. Here we studied the pathomechanism of H. pylori and the role of the cag-pathogenicity island (cag-PAI) for the induction of gastric ulcer and precancerous conditions over time (2–64 weeks) using the Mongolian gerbil model. Animals were challenged with H. pylori B128 (WT), or an isogenic B128ΔcagY mutant-strain that produces CagA, but is unable to translocate it into gastric cells. H. pylori colonization density was quantified in antrum and corpus mucosa separately. Paraffin sections were graded for inflammation and histological changes verified by immunohistochemistry. Physiological and inflammatory markers were quantitated by RIA and RT-PCR, respectively. An early cag-T4SS-dependent inflammation of the corpus mucosa (4–8 weeks) occurred only in WT-infected animals, resulting in a severe active and chronic gastritis with a significant increase of proinflammatory cytokines, mucous gland metaplasia, and atrophy of the parietal cells. At late time points only WT-infected animals developed hypochlorhydria and hypergastrinemia in parallel to gastric ulcers, gastritis cystica profunda, and focal dysplasia. The early cag-PAI-dependent immunological response triggers later physiological and histopathological alterations towards gastric malignancies
Resolution of LPS-induced airway inflammation and goblet cell hyperplasia is independent of IL-18
BACKGROUND: The resolution of inflammatory responses in the lung has not been described in detail and the role of specific cytokines influencing the resolution process is largely unknown. METHODS: The present study was designed to describe the resolution of inflammation from 3 h through 90 d following an acute injury by a single intratracheal instillation of F344/N rats with LPS. We documented the inflammatory cell types and cytokines found in the bronchoalveolar lavage fluid (BALF), and epithelial changes in the axial airway and investigated whether IL-18 may play a role in the resolution process by reducing its levels with anti-IL-18 antibodies. RESULTS: Three major stages of inflammation and resolution were observed in the BALF during the resolution. The first stage was characterized by PMNs that increased over 3 h to 1 d and decreased to background levels by d 6–8. The second stage of inflammation was characterized by macrophage influx reaching maximum numbers at d 6 and decreasing to background levels by d 40. A third stage of inflammation was observed for lymphocytes which were elevated over d 3–6. Interestingly, IL-18 and IL-9 levels in the BALF showed a cyclic pattern with peak levels at d 4, 8, and 16 while decreasing to background levels at d 1–2, 6, and 12. Depletion of IL-18 caused decreased PMN numbers at d 2, but no changes in inflammatory cell number or type at later time points. CONCLUSION: These data suggest that IL-18 plays a role in enhancing the LPS-induced neutrophilic inflammation of the lung, but does not affect the resolution of inflammation
Integrated genomic characterization of oesophageal carcinoma
Oesophageal cancers are prominent worldwide; however, there are few targeted therapies and survival rates for these cancers remain dismal. Here we performed a comprehensive molecular analysis of 164 carcinomas of the oesophagus derived from Western and Eastern populations. Beyond known histopathological and epidemiologic distinctions, molecular features differentiated oesophageal squamous cell carcinomas from oesophageal adenocarcinomas. Oesophageal squamous cell carcinomas resembled squamous carcinomas of other organs more than they did oesophageal adenocarcinomas. Our analyses identified three molecular subclasses of oesophageal squamous cell carcinomas, but none showed evidence for an aetiological role of human papillomavirus. Squamous cell carcinomas showed frequent genomic amplifications of CCND1 and SOX2 and/or TP63, whereas ERBB2, VEGFA and GATA4 and GATA6 were more commonly amplified in adenocarcinomas. Oesophageal adenocarcinomas strongly resembled the chromosomally unstable variant of gastric adenocarcinoma, suggesting that these cancers could be considered a single disease entity. However, some molecular features, including DNA hypermethylation, occurred disproportionally in oesophageal adenocarcinomas. These data provide a framework to facilitate more rational categorization of these tumours and a foundation for new therapies.ope
Integrated genomic characterization of oesophageal carcinoma
Oesophageal cancers are prominent worldwide; however, there are few targeted therapies and survival rates for these cancers remain dismal. Here we performed a comprehensive molecular analysis of 164 carcinomas of the oesophagus derived from Western and Eastern populations. Beyond known histopathological and epidemiologic distinctions, molecular features differentiated oesophageal squamous cell carcinomas from oesophageal adenocarcinomas. Oesophageal squamous cell carcinomas resembled squamous carcinomas of other organs more than they did oesophageal adenocarcinomas. Our analyses identified three molecular subclasses of oesophageal squamous cell carcinomas, but none showed evidence for an aetiological role of human papillomavirus. Squamous cell carcinomas showed frequent genomic amplifications of CCND1 and SOX2 and/or TP63, whereas ERBB2, VEGFA and GATA4 and GATA6 were more commonly amplified in adenocarcinomas. Oesophageal adenocarcinomas strongly resembled the chromosomally unstable variant of gastric adenocarcinoma, suggesting that these cancers could be considered a single disease entity. However, some molecular features, including DNA hypermethylation, occurred disproportionally in oesophageal adenocarcinomas. These data provide a framework to facilitate more rational categorization of these tumours and a foundation for new therapies
Identification Of Cell Wall Deficient Forms Of M. Avium Subsp. Paratuberculosis In Paraffin Embedded Tissues From Animals With Johne\u27S Disease By In Situ Hybridization
M. avium subsp. paratuberculosis (M. paratuberculosis) is the causative agent of Johne\u27s disease (JD) in ruminants leading to enormous economical losses in dairy and meat industries worldwide. During the subclinical stage of the disease, the infected animals are difficult if not impossible to detect by the available diagnostic tests including the PCR based ones. Although only considered an animal pathogen, cell wall deficient (CWD) forms of M. paratuberculosis have been isolated from patients with sarcoidosis and Crohn\u27s disease (idiopathic diseases) in humans. Hence, the CWD form of this organism has been suspected to play a role in the pathogenesis of these diseases by persisting in the affected tissues and triggering a localized immune response and pathology. Differentiating between the CWD and acid-fast forms of this organism may lead to the determination of whether the CWD form is the pathogenic form in the subclinical cases of JD in animals and/or the etiologic agent for the above human diseases. To localize such organisms in tissue sections, CWD forms of mycobacteria were prepared in vitro and injected into beef cubes which were then formalin fixed and paraffin embedded. An in situ hybridization (ISH) technique, combined with the IS900 M. paratuberculosis-specific probe labeled with digoxigenin, was developed for the detection of nucleic acids specifically from the CWD forms but not their acid-fast forms in tissue sections. Specificity was confirmed by the negative finding with an irrelevant probe and with control tissue preparations containing CWD cells of related mycobacteria and unrelated organisms. This ISH procedure provides a way to distinguish between the acid- fast and CWD forms of M. paratuberculosis and to localize them in tissue sections. ISH may prove useful to evaluate the significance of CWD forms of M. paratuberculosis in the pathogenesis of JD, Crohn\u27s disease and sarcoidosis. (C) 2000 Elsevier Science B.V
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