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A sensitive enzyme immunoassay (immune complex transfer enzyme immunoassay) for (anti-human T-cell leukemia virus type I) IgG (anti-HTLV-I IgG) in serum using recombinant gag p24(14-214) of HTLV-I is described. The recombinant gag p24(14-214) is soluble in the absence of detergents and allows the use of enzymes other than horseradish peroxidase as a label in the assays. The usefulness of recombinant gag p24(14-214) was examined with 305 sera characterized by other methods including gelatin particle agglutination, enzyme-linked immunosorbent assay (ELISA) using HTLV-I, and Western blotting. This assay was more sensitive than other methods using HTLV-I as antigen. The specificity could be tested by preincubation of test serum with excess of the recombinant protein. Most of negative and positive sera were discriminated. However, some results appeared to be false-positive or false-negative, and recombinant gag p24(14-214) was suggested to be useful, when used with other recombinant proteins and/or peptides, for improving the reliability of serodiagnosis by separately demonstrating antibodies against as many different epitopes of HTLV-I as possible. Anti-HTLV-I IgG in test serum, which had been incubated with excess of inactive beta-D-galactosidase to eliminate interference by anti-beta-D-galactosidase antibodies, was reacted simultaneously with 2,4-dinitrophenyl-bovine serum albumin-recombinant gag p24(14-214) conjugate and recombinant gag p24(14-214)-beta-D-galactosidase conjugate. The complex formed consisting of the three components was trapped onto polystyrene balls coated with affinity-purified (anti-2,4-dinitrophenyl group) IgG.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Morphologic Variants of Alcoholic Hyalin   总被引:10,自引:3,他引:7       下载免费PDF全文
Liver biopsies obtained from 24 patients with alcoholic liver disease were studied by light and electron microscopy. Comparisons of the same cells in adjacent sections revealed that alcoholic hyalin is a fibrillar deposit without limiting membranes and is readily distinguished from giant mitochondria. This characteristic fibrillar structure was encountered in hepatocytes, ductular cells and in benign and malignant hepatomas. Three distinct morphologic forms of alcoholic hyalin were observed: a) bundles of filaments in parallel arrays, b) clusters of randomly oriented fibrils and c) a granular or amorphous substance containing only scattered remains of fibrils. Closely associated with alcoholic hyalin and often found along its entire circumference, were bundles of fine filaments in parallel arrangement of much smaller size. These occasionally displayed variations in orientation and merged with the filaments in the alcoholic hyalin body. Similar fine filaments were observed, in considerable excess, in cells which did not contain alcoholic hyalin. According to our findings, the fine filaments and the significantly larger filaments in alcoholic hyalin could be parts of a contractile system elaborated by host cells during the course of hepatic injury.  相似文献   
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Understanding the molecular action of gefitinib, an epidermal growth factor receptor tyrosine kinase inhibitor, might allow us to perform more effective therapies for hormone-independent advanced prostate cancer. A DNA microarray study was undertaken to comprehensively analyze the alteration of levels of 1,081 genes after gefitinib treatment in androgen-independent PC3 and DU145 cells and androgen-dependent LNCaP cells. The proliferation of PC3, DU145 and LNCaP cells was significantly inhibited by 50.2%, 83.8% and 55.2%, respectively, 6 days after 10 microM gefitinib administration. Of the above 1,081 genes, we identified 23, 13 and 33 genes with significantly different expression in PC3, DU145 and LNCaP cells, respectively, 24 h after 10 microM-gefitinib exposure. Among the identified genes, only Quiescin Q6, a negative cell cycle regulator, was increased after gefitinib treatment in all three cell lines regardless of gefitinib sensitivity. Except for Quiescin Q6, there were no overlapping genes between PC3 and DU145 cells. However, levels of several oncogenes or proliferation-related genes were changed after gefitinib treatment in the 2 androgen-independent cell lines. We also identified 7 unique genes [glycyl-tRNA synthetase, interferon, alpha-inducible protein, stratifin, nuclear factor of kappa light polypeptide gene enhancer in B-cells 1, dual specificity phosphatase 9, guanine nucleotide binding protein (G protein) beta polypeptide 2, neural retina leucine zipper] whose levels were altered exclusively after gefitinib administration in gefitinib-resistant PC3 and LNCaP cells, but not in DU145 cells, suggesting that these 7 genes could be targets for overcoming gefitinib resistance. Collectively, our molecular profiling data will serve as a framework for understanding the molecular action of gefitinib for prostate cancer.  相似文献   
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Six cases of primary lung cancer that closely mimic malignant pleural mesothelioma clinically and anatomically are compared with four proven cases of malignant pleural mesothelioma. Findings on roentgenograms of the chest, clinical history, and gross examination of the lung specimens are not helpful in distinguishing between these two neoplasms. Microscopic examination of the hematoxylin and eosin-stained tissues is often inconclusive. Tissues were stained with hematoxylin and eosin, PAS with and without diastase treatment (DPAS), mucicarmine, alcian blue, toluidine blue, and colloidal iron with and without digestion by testicular hyaluronidase. Among these histochemical methods, DPAS was found to be particularly useful in distinguishing the primary lung cancers from the mesotheliomas. All primary lung cancers except one showed DPAS-positive material (mucin) in both the cytoplasm of the cancer cells and within the lumina of neoplastic glands. In contrast, none of the mesotheliomas showed the presence of DPAS-positive material. Histologically, all lung cancers were glandular. Five were classified as bronchiolar carcinoma, the remaining one as poorly differentiated adenocarcinoma. In two of the bronchiolar carcinomas, a small subpleural primary focus was demonstrated. This finding suggests a possible origin of these cancers as a small subpleural tumor that became widely disseminated via the subpleural lymphatics. This form of primary lung cancer possesses sufficient gross and microscopic characteristics that recognition should be given to it as a variant of primary lung cancer, with emphasis on differentiating it from pleural mesothelioma.  相似文献   
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