PubMed Health⌕ Search

Biomedical subjects

Michael Vieth

Publications and source records attributed to Michael Vieth.

59 records · Page 4Linked to original sources
PubMed2002

Gastric-type adenocarcinoma of the duodenal second portion histogenetically associated with hyperplasia and gastric-foveolar metaplasia of Brunner's glands.

We report a case of a pedunculated polyp with a focus of gastric-type adenocarcinoma arising in the opposite side of the papilla Vater of the duodenal second portion. The carcinoma was surrounded by lobules of hyperplastic Brunner's glands. Immunohistochemically the carcinoma tissue showed both gastric foveolar-type mucin ( MUC5AC) and pyloric/Brunner's gland-type mucin ( MUC6), in which proliferating cells positive for MIB-1 (Ki-67) were scattered diffusely. Most of the hyperplastic Brunner's glands were positive for MUC6, while cells toward the lumen in the superficial layer were positive for MUC5AC and MIB-1. This directional pattern of differentiation of Brunner's glands has recently been demonstrated by our group in the histogenetic course of gastric metaplasia originating directly from Brunner's glands. Therefore the present carcinoma is thought to have developed under induction of gastric-foveolar differentiation in a manner very similar to that of gastric metaplasia in hyperplastic Brunner's glands.

Adenocarcinoma↗
PubMed2002

Expression of G1 phase cyclins in human gastric cancer and gastric mucosa of first-degree relatives.

The aim of this study was to investigate the expression of D-type cyclins and cyclin E in gastric cancer patients (N = 34), in healthy first-degree relatives of gastric cancer patients (N = 29), and in control subjects (N = 18). Expression of cyclins D1, D2, D3, and E was determined by RT-PCR. Localization of cyclin expression was determined by immunohistochemistry. Expression of cyclins D2, D3, and E was more frequently detected in tumor tissue compared with tumor-free gastric mucosa (P < 0.05) and was associated with the presence of intestinal metaplasia. In contrast, cyclin D1 was frequently expressed in both tumor- and tumor-free tissue. Cyclin D3 expression was more frequently detected in the antrum mucosa of first-degree relatives compared to controls (P < 0.01) and was associated with the presence of Helicobacter pylori. Our data suggest that deregulation of G1 phase cyclins may play a role in gastric carcinogenesis, and may point to the presence of molecular alterations in individuals at an increased risk for gastric cancer.

Aged↗
PubMed2002

Local endoscopic therapy for intraepithelial high-grade neoplasia and early adenocarcinoma in Barrett's oesophagus: acute-phase and intermediate results of a new treatment approach.

BACKGROUND: Radical oesophageal resection has until now been regarded as the gold standard for treatment in intraepithelial high-grade neoplasia or early adenocarcinoma of the oesophagus. However, the mortality and morbidity rates are substantial. DESIGN: A new therapeutic approach involving low-risk endoscopic therapy modalities was examined in the framework of a prospective study. PATIENTS: A total of 115 patients with intraepithelial high-grade neoplasia (19) and early adenocarcinoma (96) in Barrett's oesophagus. METHODS: Endoscopic mucosal resection (EMR) was used in 70 patients, and photodynamic therapy (PDT) was used in 32 patients. The two procedures were combined in ten patients. Three patients underwent primary treatment with argon plasma coagulation (APC). The average follow-up was 34 +/- 10 months (range 24-60 months). RESULTS: Complete local remission was achieved in 98%. The overall complication rate was 9.5%. Major complications, such as perforation and severe bleeding, did not occur. Minor complications included not haemoglobin relevant bleeding (drop of haemoglobin less than 2 g/dl) (5) and stenosis (3) after EMR, and long-lasting odynophagia (1) and sunburn (2) after PDT. In all, 13 patients have died so far, but in only one case due to the underlying disease. The calculated overall 3-year survival rate is 88%. During the follow-up period, a 30% rate of metachronous lesions was observed; endoscopic therapy was performed successfully in all but one of these patients. CONCLUSIONS: These good acute-phase and intermediate results, along with low morbidity rates and no mortality, suggest that the organ-preserving local endoscopic procedure including EMR and PDT is an attractive alternative to oesophageal resection. Therefore, endoscopic therapy might replace radical oesophageal resection in future in cases of intraepithelial high-grade neoplasia and early mucosal adenocarcinoma in Barrett's oesophagus.

Adenocarcinoma↗
PubMed2002

Role of tumor necrosis factor alpha in Helicobacter pylori gastritis in tumor necrosis factor receptor 1-deficient mice.

Increased gastric production of interleukin 8 and tumor necrosis factor alpha (TNF-alpha) has been implicated in the pathogenesis of Helicobacter pylori-associated gastroduodenal disease. In the present study we used a mouse model to demonstrate whether loss of the tumor necrosis factor receptor 1 (TNF-R1) function leads to differences in gastric inflammation or the systemic immune response in H. pylori infection. Six different clinical isolates of H. pylori (three cytotoxin-positive and three cytotoxin-negative strains) were adapted to C57BL/6 mice. TNF-R1-deficient (TNF-R1(-/-)) mice (n = 19) and isogenetic controls (n = 24) were infected and sacrificed after 4 weeks of infection. Inflammation of the stomach and the humoral immune response to H. pylori were evaluated by histological, immunohistochemical, and serological methods. There was no detectable difference in the grade or activity of gastritis in TNF-R1(-/-) mice when they were compared with wild-type mice, but the number of lymphoid aggregates was slightly reduced in the gastric mucosa of TNF-R1(-/-) mice. Interestingly, total immunoglobulin G (IgG), as well as IgG1, IgG2b, and IgG3, H. pylori-specific antibody titers were significantly higher in wild-type mice. As revealed by immunoblot analysis, the difference in reactivity against H. pylori antigens was not based on a failure to recognize single H. pylori antigens in TNF-R1(-/-) mice. We therefore suggest that TNF-R1-mediated TNF-alpha signals might support a systemic humoral immune response against H. pylori and that the gastric inflammatory response to H. pylori infection seems to be independent of TNF-R1-mediated signals.

Animals↗