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21.
A new commercial rapid 10-min one-step immunochromatography (IC) test, SAS RSV test, was compared to another IC test, Directigen EZ RSV, employing RT-PCR as the "gold standard" for detecting respiratory syncytial virus. Of 102 clinical samples, 79 were positive by RT-PCR, 66 (82.5%) were positive with the SAS RSV test, and 55 (69.6%) were positive with Directigen EZ RSV. The specificity of the new test was 91.3% (21 of 23), similar to that of Directigen EZ RSV (100% [23 of 23]). This test performs well enough to be used for patient care.  相似文献   
22.
Summary Nineteen hybridomas producing monoclonal antibodies (MAbs) against the structural proteins of strain 58–17, a subgroup B field strain of respiratory syncytial virus (RSV) isolated in Japan, were obtained by fusion of X 63 myeloma cells with spleen cells from BALB/c mice immunized with the virus-infected HEp-2 cells. Seven clones were found to produce antibodies against the fusion protein (F), five against the large glycoprotein (G), five against the nucleoprotein (NP) and two against the 22k protein by radioimmunoprecipitation assay. By competitive binding assay with the MAbs, at least seven, two, three and one epitopes were defined on the F, G, NP and 22k protein components of subgroup B strain, respectively. Of these epitopes, three, two and one epitopes on the F, G and NP components were different from subgroup A strain, respectively. Fifty-three other field strains of subgroup B isolated in Sapporo, Japan, during nine epidemic years from 1980 to 1989, were examined for reactivity with the MAbs by ELISA. Different reactivity to one anti-NP antibody suggested that the 53 strains can be divided into three groups (B-a: 26 strains, B-b: 26 strains, and one other strain). The dominant strain prevailing during the 1984 to 1988 epidemic years had changed from B-a to B-b. All of the 53 subgroup B strains reacted similarly with the other 18 MAbs.  相似文献   
23.
Premalignant cervical lesions occur at the squamo-columnar junction and in endocervical epithelium and squamous ectocervical epithelium, in descending order of frequency. However, previously only ectocervical cells have been clearly shown to be immortalized in vitro by the oncogenic human papillomaviruses (HPVs). This report describes the immortalization of normal human ecto- and endocervical epithelial cells by the intact HPV 16 genome. Ectocervical epithelial cells (HEC) became immortalized (HEC-16) without crisis while endocervical cells (HEN) were immortalized (HEN-16) after undergoing crisis. HEN-16 and HEC-16 contained integrated HPV 16 DNA, expressed E6 and E7 mRNA, and were aneuploid and nontumorigenic. They also expressed cytokeratins in a pattern similar to their distinct normal parental cells. These results suggest that both squamous and simple epithelial cells of uterine cervix are targets for immortalization by HPV 16.  相似文献   
24.
A case of malignant Brenner tumor with peritoneal metastasis in a 67-year-old woman was reported. The multilocular cystic tumor of right ovary was 420 g in weight, and their cystic walls were covered with multilayered tumor cells showing papillary pattern very frequently. The tumor was histologically transitional cell carcinoma with occasional glandular structures but no squamous differentiation corresponding to grade 2 or 3 urinary bladder carcinoma. The pattern of benign Brenner tumor was not identified, but there was some area of proliferating Brenner tumor. Immunohistochemically, carcinoembryonic antigen was detected in several tumor cells, especially in the intercellular spaces among them, and cytokeratin was detected only in some tumor cells. Ultrastructurally, the malignant Brenner tumor shared many common features with the benign one and also bladder tumor. Intercellular spaces with microvilli were frequently found and thought to be important for diagnosis. The morphologic criteria of this rare tumor are discussed.  相似文献   
25.
Summary Twenty-one specimens of heterotopic pancreas were investigated using the indirect immunoperoxidase method for insulin, somatostatin, glucagon, pancreatic polypeptide (PP) and gastrin. Ten specimens showed ducts, acini and islets, seven showed ducts and acini, and four showed a ductal component alone. Pyloric gland-like mucous glands were occasionally identified in association with the ductal component. In eight of ten lesions containing islets, the islets were round and had a clearly defined outline with many glucagon cells and either none or a modest number of PP cells (dorsal type). In the remaining two lesions, the islets showed varying sizes and irregular outline with many PP cells and a few or no glucagon cells (ventral type). In either type of islets, insulin and somatostatin were detected, but gastrin cells were absent. Some isolated endocrine cells were also present among the acinar and ductal components. Their occurrence in ducts was more frequent in lesions or areas mainly composed of the ductal compoment than in those with less prominent ductal tissue. In eight lesions a few gastrin cells were found in the ductal component which showed goblet cell metaplasia and pyloric gland metaplasia. An intimate relationship between goblet cell metaplasia and appearance of G cells is noteworthy.  相似文献   
26.
Anti-glucose-6-phosphate isomerase (GPI) antibodies (Abs) solely induce arthritis in mice. High titers of anti-GPI Abs are found in some patients with rheumatoid arthritis (RA), but their pathogenic role remains elusive. The aim of this study was to evaluate the pathogenic role of anti-GPI Abs in cynomolgus monkeys. IgG fractions were separated from sera of anti-GPI Abs-positive RA patients and healthy subjects and directly injected into the metacarpophalangeal joints of 4 cynomolgus monkeys. At day 16, the joints were harvested and examined histologically and immunohistochemically. The expression of C5a receptor (C5aR) molecule in the synovium was quantified by real-time PCR using cDNA from monkey joints. In monkey joints, IgG including anti-GPI Abs resulted in recruitment of granulocytes and mononuclear cells, strong deposition of human IgG on the articular surface, and overexpression of C5aR, but no joint swelling. No infiltrated cells or IgG deposition were observed in monkeys injected with IgGs from healthy subjects. Our results suggest that IgG fraction from RA patients including anti-GPI Abs may play a crucial role in the generation of synovitis in monkeys, although the pathogenesis of anti-GPI Abs in RA patients is still uncertain.  相似文献   
27.
IgA synthesized in hepatobiliary tissues accounts for about one-half of the IgA present in human hepatic bile, but the location of the IgA synthesizing cells has been in doubt because few plasma cells are present in normal liver. Therefore, we immunocytochemically localized IgA, J chain and secretory component in bile duct tissues of six patients operated upon for biliary duct obstruction. Numerous plasma cells containing IgA and J chain were found surrounding the accessory glands of the major bile ducts and in the area just beneath the surface epithelium of the ducts. At the ultrastructural level, IgA and SC in the epithelial cells had the features characteristic of secretory component-mediated endocytic translocation of IgA. We conclude that plasma cells in biliary duct mucosa are the likely source of much of the locally synthesized IgA that is secreted into human hepatic bile. The IgA probably reaches the bile by direct transfer across biliary epithelium.  相似文献   
28.
We recently obtained 3 cloned cell lines demonstrating the p53 mutation from a lung metastatic nodule of a rat transplantable osteosarcoma. In this study, we applied wild-type p53 gene transfer to the rat osteosarcoma cells by lipofection to investigate the effects on cell growth, expression of genes such as waf1/p21, bcl-2, and bax, and nucleosomal DNA fragmentation due to apoptosis. Reconstitution of the p53 gene inhibits cellular growth, and this growth-suppressive effect is partly due to apoptosis involving bcl-2 gene suppression in this tumor type. This rat osteosarcoma model is similar in biologic behavior to human cases and thus is very suitable for further investigation of tumorigenesis and gene therapy for osteosarcoma.  相似文献   
29.
Tumour necrosis factor alpha (TNFalpha), a proapoptotic cytokine, is known to be present in peritoneal fluid from women with endometriosis. An emerging view is that soluble TNF receptors (sTNFR) can modulate the effects of TNFalpha by acting as TNFalpha antagonists. To assess the relevance of sTNFRs in the pathophysiology of endometriosis, concentrations of sTNFR I, sTNFR II and TNFalpha in peritoneal fluid from women with endometriosis (n = 53) and without endometriosis (n = 40) were measured. Concentrations of both sTNFR I and sTNFR II in peritoneal fluid from women with endometriosis were significantly higher than in peritoneal fluid from women without endometriosis, both in the follicular and the luteal phases. TNFalpha concentrations did not differ in patients with and without endometriosis in both phases. When stratified by the stage of the disease, women with both stages I/II and stages III/IV exhibited significantly higher concentrations of sTNFR I and sTNFR II in peritoneal fluid, compared with women without endometriosis, whereas no appreciable difference in the concentrations was detected between stages I/II and stages III/IV. A significant correlation was found between the concentrations of sTNFR I and sTNFR II; while the correlations between TNFalpha and sTNFR I or sTNFR II, were either not significant or were very weak. Furthermore, mRNA for the membrane-associated TNF receptor type 1 and TNF receptor type 2, both of which convey the effects of TNFalpha, were shown to be expressed in endometriotic tissues as well as eutopic endometrium. Together, these findings suggest a possible involvement of sTNFRs in the pathophysiology of endometriosis.  相似文献   
30.
Previous studies have suggested that heat shock proteins (HSP) of Helicobacter pylori (H. pylori) are involved in the induction of autoimmunity mediated gastritis. In the present report, the cross-reactivity between H. pylori-related HSP60 and gastric epithelial cells was investigated by the indirect immunoperoxidase method using two monoclonal antibodies (mAb) against H. pylori-derived HSP60, H9 and H20. H9 is reactive with an epitope common to bacterial HSP60, while H20 is specific to H. pylori HSP60. A total of 70 paraffin-embedded gastric biopsy specimens were analyzed after heat-induced epitope retrieval. Both mAb were cross-reactive with the gastric epithelial cells, with a higher frequency seen for the H9-reactive epitope. The frequency of positive epithelial decoration was not significantly different between H. pylori-positive and H. pylori-negative gastric mucosae. A variety of epithelial and non-epithelial cells were immunostained with mAb H9, while mAb H20 was cross-reactive only with small intestinal epithelia. Reactivity was mainly located in the Golgi area and rarely in the cytoplasm. These results suggest a noteworthy pitfall in immunohistochemical interpretations of HSP60-associated autoimmune reactions in the gastric mucosa.  相似文献   
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