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Biomedical subjects

W Schlake

Publications and source records attributed to W Schlake.

16 recordsLinked to original sources
PubMed1979

Quantification of BCG-induced reactions of T and B areas in peripheral lymphoid organs of young adult BALB/c mice. A histomorphometrical and autoradiographical study.

Significant structural alterations of the axillary lymph nodes and spleens were revealed by histomorphometry following intraperitoneal injection of BCG into young adult BALB/c mice. The relative proportions of the germinal center areas were increased in lymph nodes as well as in spleens. The overall proportion of the B cell areas, however, showed a significant increase only in the spleens, compared to a significant reduction in the lymph nodes. By contrast, T cell areas appeared significantly reduced in the spleens, while their size was almost doubled in the lymph nodes. The labeling index in the lymph node paracortical areas was also doubled autoradiographically. The structural changes in the lymph nodes and spleens differed not only in quality, but also in their time course. In lymph nodes, the altered proportions of the T and B cell areas persisted from the second through the sixth week after BCG treatment. By contrast, structural changes in the spleen began to subside 2 weeks after treatment, and after 6 weeks the proportions of the T and B cell areas in the spleen had returned to normal. These quantitative morphologic findings suggest a difference in the functional roles of lymph nodes and spleen in the systemic immune response to BCG.

Animals↗
PubMed1979

Comparative histologic, histochemical, and histomorphometric studies of T and B cell areas in peripheral lymphoid organs of normal young adult BALB/C mice.

T cell areas can be distinguished from adjacent B cell compartments in routinely stained histologic sections of paraffin-embedded mouse lymph nodes and spleens by their comparatively loose texture. The reliability of this morphologic criterion for identifying T cell areas has been proven in comparative histologic, enzyme-histochemical, and immunohistochemical investigations. It is thus possible to determine the size of functionally different compartments in the lymph nodes and spleen of the mouse with sufficient accuracy by the use of conventional histologic techniques. According to our subsequent histomorphometrical studies in two groups of inbred mice matched with respect to age and strain, the proportions of B cell areas in the peripheral lymphoid organs varied significantly depending on environmental conditions, whereas the proportions of T cell areas were stable.

Age Factors↗
PubMed1979

Multifocal early gastric cancer of mixed type.

A report of three selected gastric resection specimens presents the problems of histological classification of individual early gastric cancer, illustrated in discrepancies between macroscopic or endoscopic, and histologic identification. Multifocal origin and different types of gastric cancer are demonstrated in all three cases. Problems related to exact histologic classification of this mixed type are discussed together with the prognosis and surgical consequences.

Adenocarcinoma↗
PubMed1979

Gastric stump carcinoma -- carcinogenic factors and possible preventive measures.

Cancer in the resected stomach has a very poor prognosis unless it is detected at the "early gastric cancer" stage. The development of gastric stump carcinoma is probably dependent on the procedure chosen for primary surgery (resection). Local irritation accompanying the execution of anastomosis is also discussed as a possible cause of malignant transformation. Surgical precautions should include the choice of methods avoiding reflux, and the use of resorbable suture material for performing an exact and well-matched anastomosis. Periodic postoperative control is essential; in addition to radiological methods, endoscopy and biopsy are indicated for adequate identification of local abnormalities and mucosal changes. Patients whose high risk was stated in previous examinations, must be re-examined at shorter intervals. Identification of changes at the early cancer stage requires close cooperation of surgeon and pathologist.

Duodenum↗
PubMed1978

Comparison of the methods of cathodoluminescence, electronprobe microanalysis, and calcium staining, applied to human aorta with isthmus stenosis.

Electron probe x-ray microanalysis is a useful method for studying pathologic and age-related calcification mechanisms in the aorta and in muscular arteries by means of elemental analysis in microareas. In the present investigation, this method was correlated with the histochemical alizarin-S-calcium staining and with cathodoluminescence analysis in the scanning electron microscope. Portions of the proximal region of a human aorta with isthmus stenosis was shock-frozen and sectioned in a cryostat. Serial sections were investigated by calcium staining, electron probe, and cathodoluminescence microanalysis. Using quantitative electron probe microanalysis of calcium and phosphorus, it was shown that the principal regions of calcium phosphate mineralization could be located using either alizarin-S staining or cathodoluminescence analysis. The advantage of the cathodoluminescence analysis is its higher lateral resolution compared with that of light microscopy, and the fact that no special staining is required. In addition, it was possible to obtain scanning images, thus providing additional information about the topology of the tissue surface, which is necessary to decide whether or not the section is suitable for microanalysis. Quantitative microanalysis is a valuable tool for basic research on calcified arteries. The results of the combined analysis in the proximal and distal regions as well as in the stenosis will be published in a later paper.

Aortic Coarctation↗
PubMed1978

Histochemical identification of T and B areas in paraffin-embedded lymphoid tissues by demonstration of alpha-naphthyl acetate esterase (ANAE) activity.

A strong activity of acid alpha-naphthyl acetate esterase (ANAE) in T lymphocytes and macrophages within mouse lymphoid organs is demonstrable even after paraffin-embedding, if a rapid embedding procedure with acetone as dehydrating agent is used. The lymphoid tissue structure is better preserved in paraffin sections procured after this rapid embedding procedure than in frozen sections commonly used for histochemical demonstration of ANAE. In the paraffin sections the pattern of the ANAE reaction allows a clear delineation of the T and B areas in the lymphoid organs, and the intracellular location of the focal ANAE activity in T lymphocytes is readily discernible.

Animals↗
PubMed1978

[The multiple stomach carcinoid].

Carcinoid tumors can be found in the entire alimentary tract. Stomach carcinoids make up about 3% of all carcinoids; 0.39% of all stomach tumors are carcinoids. Multiple stomach carcinoid is a medical rarity. In spite of an invasive growth, carcinoids with a diameter of less than 1 cm are considered semimalignant, those with a diameter of more than 1 cm are considered sure malignant. There are 8 cases of multiple gastric carcinoids described in the literature. In our case we found macroscopically 31 polyps with a diameter of between 0.4 and 2 cm in the stomach. Histologically they were growing invasively with small tumor groups in the lymph ducts. Therapeutically total gastrectomy was necessary.

Carcinoid Tumor↗
PubMed1976

Development of tumors in the glandular stomach of rats after oral administration of carcinogens. I. Histological findings.

Experimental carcinomas in the glandular stomach of rats were induced by oral administration of MNNG (M-methyl-N'-nitro-N-nitrosoguanidin) for 35 weeks or ENNG (N-ethyl-N'-nitro-N-nitrosoguanidin) for 20 weeks. Rats were killed at different times after beginning of carcinogen treatment and tissue specimens were prepared for histologic investigation. Particular interest was placed on the development of tumors and on pathological findings possibly contributing to early diagnosis of stomach cancer. During the development of tumors, several dysplastic reactions were observed in the antral mucosa. They could be classified into 4 groups: One was regenerative hyperplasia (1) that meant irregular glandular proliferations without cell atypism at the margin of erosions and ulcers. This lesion was mainly found 1-9 weeks after administration of MNNG. In glandular hyperplasia (2) either crypts or glands were extended and mucosal layers were thickened. No signs of cell atypism were observed. This lesion was mainly found 12-17 weeks after administration of MNNG. Dysplasia (3) was combined with considerable structural modifications and cellular atypism. However, this lesion was limited to the mucosal layer. Neoplastic changes (4) were characterized by marked cellular atypism and extension to tunica submucosa and tunica serosa. Some tumors showed the histological patterns of benign tumors, but most of them were adenocarcinomas. In some cases metastases into pancreas, liver and lymph nodes and in one case into the 12th rib were observed. No particular enzyme patterns were found by histochemistry.

Animals↗
PubMed1976

Development of tumors in the glandular stomach of rats after oral administration of carcinogens. II. Different cell types in antral carcinoma as revealed by electron microscopy.

In the present study electron microscopic investigations of tumors of the glandular stomach of rats induced by oral administration of MNNG or ENNG are dealt with. The aim of the study was to describe the different cell types found in the carcinoma and to elucidate the possible relationship between the undifferentiated carcinoma cells and the more differentiated cell types found in the tumor. The results show that besides undifferentiaded carcinoma cells, several differentiated cell types such as goblet cells, endocrine cells, cells with lamellated inclusions in their cytoplasm, and squamous carcinoma cells can be observed. The most conspicuous findings were carcinomatous gland cells with well differentiated microvilli on their luminal surface and typical tonofilamentous structures in their cytoplasm. These cells exhibited signs of the squamous epithelium and of gland cells. Therefore they may be considered as intermediate variants between adenocarcinoma cells and squamous carcinoma cells. The occurrence of such intermediate steps points to the possibility of differentiation by cell division of adenocarcinoma cells into several metaplastic cell types in the experimental stomach carcinoma induced by MNNG or ENNG.

Adenocarcinoma↗
PubMed1975

[The use of laser in thoracic-, cardiac- and vascular surgery (author's transl)].

We carried out thoracic and cardiovascular operations with a 50 watt CO2-Laser. The advantage of this procedure: A minimal trauma of tissue in consequence of no use of selfcutting surgical instruments, bloodless incision at smallest area of coagulation and no possibility of displacement of infections and tumor cells. We believe that this new laser in all surgical disciplines introduced soon.

Aorta↗