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Analysis of adenomatous structures in histopathology 总被引:2,自引:0,他引:2
K K Kayser B Kiefer H Toomes H U Burkhard 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》1987,9(3):273-278
A new idea of structure analysis in histopathology based upon first-order and third-order structures is presented. Networks formed by single cells and by tubulopapillary formations in adenomatous tissue were analyzed. The algorithm applied is based on the neighborhood conditions defined by O'Callaghan, using graph theory procedures. Twenty cases each of healthy colon mucosa, tubulovillous adenomas and highly to moderately differentiated adenocarcinomas of colon plus ten cases of mesotheliomas and ten cases of adenocarcinomas metastatic to the pleura were analyzed. Statistically significant differences were found in the cyclomatic number of neighboring elements. Classification of specimens of colon mucosa using discriminant analysis yielded correct results in 85% of the 20 cases. All ten cases of metastatic adenocarcinoma and nine of the ten cases of mesothelioma were also correctly classified by the same procedure. A trial of prospective diagnostic assistance in routine histology based upon these cases gave correct classification of three mesotheliomas and of two adenocarcinomas. The procedures are now being used successfully in the routine diagnosis of pleural epithelial/biphasic mesothelioma and of pleuritis carcinomatosa. 相似文献
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Summary The activity of a cysteine proteinase, cathepsin B (EC 3.4.22.1), was determined in unfixed single human thyroid follicular
epithelial cells at room temperature using an image analysis system. The formation of the reaction product was monitored every
minute by measuring the increasing fluorescence intensity of emitted light from a Schiff-base product formed by the substrateN-CBZ-ala-arg-arg-4-methoxy-2-naphthylamide and the coupling agent 5-nitrosalicylaldehyde. Non-specific fluorescent signals
were eliminated by adjusting the video signal to zero using leupeptin, a specific inhibitor of cathepsins B, H and L.
The enzyme activity was expressed as fluorescence intensity versus time. After a mean lag period of 5 min (range 4–8 min,n=4), the enzyme activity increased linearly lasting on average 5 min (range 3–8 min), followed by a marked decrease in reaction
rate for 3 min (range 1–4 min), and another linear increase for 11 min (range 8–14 min). The second linear part of the curve
was not as steep as the first one. The reaction velocity recorded in individual granules resulted either in a biphasic curve
or straight line, suggesting the presence of two distinct organelle compartments with differences in membrane permeability.
It is concluded that human thyroid follicular epithelial cells in culture exhibit cathepsin B activity which can be monitored
continuously by videomicrofluorometry without interference from non-specific fluoresence.
Part of this study has been presented in a preliminary form at the 9th International Congress of Histochemistry and Cytochemistry
1992 (Kayser & H?yer, 1992). 相似文献
447.
The epithelioid granulomas, interstitial and intra-alveolar mononuclear inflammatory infiltrates and the cellular compartments obtained by broncho-alveolar lavage (BAL) were measured in 40 patients with pulmonary involvement of sarcoidosis. The granulomas were divided into a central (epithelioid-cellular) zone and into a peripheral (lymphocytic-fibrotic) zone, and the density of various inflammatory cells was measured in both compartments. The cases were grouped and analyzed according to the radiological and clinical stages. The results are as follows: neutrophilic granulocytes seen in the BAL probably originate from the sarcoid granulomas in patients with stage 1 of the disease and may derive from other compartments of the lung parenchyma in patients with stage 2 or stage 3. Lymphocytes seen in the BAL of patients with stage 1 or stage 2 of the disease probably derive from intra-alveolar lymphocytic agglutinations. They originate from the sarcoid granulomas only in patients with stage 3. Macrophages seen in the BAL probably derive from the sarcoid granulomas independent from the stage of sarcoidosis. No relationship was found between the morphometric parameters and the clinical outcome of the disease. 相似文献
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Energy balance at high altitude of 6,542 m 总被引:3,自引:0,他引:3
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P M Abreu E S Martins O Kayser K U Bindseil K Siems A Seemann J Frevert 《Phytomedicine》1999,6(3):187-195
Following an ethnobotanical search carried out in Guinea-Bissau, eighteen extracts derived from sixteen medicinal species were screened for antimicrobial, antitumor and antileishmania activity. Significant antitumor activity was found for Holarrhena floribunda against KB (squamous carcinoma), SK-Mel 28 (melanoma), A 549 (lung carcinoma) and MDA-MB 231 (mamma carcinoma) cell lines, with corresponding IC50 values of 7.9, 9.0, 3.4 and 9.9 micrograms/ml. Khaya senegalensis and Anthostema senegalense exhibited a significant activity against Leishmania donovani with IC50 values of 9.8 and 9.1 micrograms/ml, respectively. Most of the extracts showed week or moderate antibacterial and antifungal activity, with MIC values in the range 0.25-1.0 mg/ml. Active extracts were submitted to bioassay-guided fractionation, and the IC50 and MIC of the active fractions were determined. 相似文献