Biomedical subjects

A Gillessen

Publications and source records attributed to A Gillessen.

24 records · Page 2Linked to original sources

PubMed1995

Collagen mRNA and fibronectin are increased in healing gastric ulcers in man.

The fibrillar collagens, types I and III, have been demonstrated in healthy human gastric mucosa as well as in the submucosa of gastric ulcer edges, where they were found to be remarkably increased. In order to verify the occurrence and activity of de novo collagen synthesis, we examined gastric biopsy specimens from six patients with antral ulcers and six normal controls. By means of in situ hybridization, using a 35-S-labelled RNA probe, we could identify the specific procollagen mRNA for type I collagen. Fibronectin was stained immunohistochemically employing specific polyclonal antibodies. In normal gastric mucosa, procollagen type I mRNA was expressed by only a very limited number of cells while at the ulcer edges the specific signal could be demonstrated in a large number of submucosal cells. Fibronectin as marker of newly built connective tissue was found to be markedly increased in the submucosa of healing gastric ulcers as compared to normal controls. These results suggest a substantial role of fibroneogenesis in the process of gastric ulcer healing.

Adult↗

PubMed1995

[Acute sigmoid diverticulitis--current diagnosis].

Acute sigmoid diverticulitis may present in different forms. Firstly, symptomatic diverticulosis and acute diverticulitis have to be differentiated to allow for the proper selection of treatment. In the initial phase of diagnostic procedures in addition to clinical features a few laboratory data, plain X-ray films of the abdomen and abdominal ultrasound are helpful to obtain information about the potential presence of perforation, abscess, tumor masses and the structure of the colonic wall. Computed tomography is capable to answer most of the questions in the diagnostic work-up of acute diverticulitis. On the other hand, contrast barium enema provides little additional information and should be considered as contraindicated in acute diverticulitis. If at all, water-soluble contrast media should be employed. Endoscopy has its place in the differential diagnostic evaluation of severe bleeding and suspected tumor, but should be reserved for these limited indications.

Acute Disease↗

PubMed1994

[The significance of cytokines and extracellular matrix for stomach ulcer healing].

The healing process of gastric ulcers is regulated by many factors. Cytokines play a central role in the different stages of healing. In the early stage of inflammation, TNF-alpha and interleukins regulate cell-migration and -proliferation. In the ulcer's base revascularisation is stimulated by b-FGF, collagen synthesis by TGF-beta. The reepithelialization is mediated by EGF, which accelerates ulcer healing in animal models, while TGF-alpha is involved in mucosal protection. The extracellular matrix (ECM) is important for the stability and quality of the ulcer scar, as known from dermatological experiments. An increase of collagen types I and III in healing gastric ulcers was demonstrated recently, which might illuminate the particular role of ECM proteins for the gastric ulcer healing process.

Animals↗

PubMed1993

Myofibroblast-like cells produce mRNA for type I and III procollagens in chronic active hepatitis.

In chronic active hepatitis the rate of collagen biosynthesis is largely determined by intracellular mRNA concentrations. To localize procollagen mRNA-producing cells, we investigated biopsy specimens from five patients with hepatitis B surface antigen-positive chronic active hepatitis and five patients without liver disease by in situ hybridization. We used type I and III procollagen cDNAs for transcription to (35S)-labeled probes. Parallel sections were stained with anti-actin monoclonal antibodies. Our results show that cells in which collagen synthesis is ostensibly enhanced can be localized by in situ hybridization of procollagen mRNAs. These cells were also anti-actin-positive in parallel sections and were localized in areas of inflammatory cell infiltration and necrosis. We conclude that myofibroblast-like cells may express procollagen mRNAs in chronic active hepatitis. Moreover, in situ hybridization may be a valuable diagnostic tool for providing additional morphologic information on the degree of fibrogenesis activity.

Actins↗

PubMed1993

Distribution of collagen types I, III, and IV in peptic ulcer and normal gastric mucosa in man.

The quality of peptic ulcer healing does not only mean complete epithelial restitution of the mucosal surface but also adequate repair of the underlying connective tissue. To obtain more information about the metabolism of extracellular matrix proteins in gastric mucosa and submucosa, we investigated biopsy specimens from six patients with antral peptic ulcers and six normal controls by staining of collagen types I, III, and IV with an immunofluorescence technique. In normal mucosa we found a certain amount of collagen types I and III in equal distribution and almost no collagen type IV. In contrast, there was a remarkable increase of collagen types I and III in peptic ulcers predominantly located at the ulcer edges. These results are compatible with the view that extracellular matrix proteins play some part in the ulcer healing process.

Collagen↗

PubMed1993

[Identification of procollagen mRNA in chronic active hepatitis B].

In situ hybridization is a tool for staining intracellular procollagen mRNAs with specific probes. Our study shows the amounts of procollagen mRNAs of types I and III to be increased in liver biopsies of five patients with chronic active hepatitis B as compared with five healthy controls. Parallel staining employing anti-smooth-muscle-actin antibodies was able to identify myofibroblast-like cells at the same localization where procollagen mRNAs were found. Consequently, these transformed Ito-cells might be the procollagen-producing cells.

Actins↗