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31.
Intraglomerular deposition of fibrin/fibrinogen-related antigen in children with various renal diseases.
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H. Kamitsuji S. Sakamoto T. Matsunaga K. Taira S. Kawahara M. Nakajima 《The American journal of pathology》1988,133(1):61-72
The localization of intraglomerular deposits of fibrin (Fb)/fibrinogen (Fg)-related antigen (FRA) in children with various glomerular diseases was determined by an immunohistopathologic method using an anti-Fg antibody capable of detecting FRA, an anti-D-dimer antibody capable of detecting crosslinked Fb (XLFb) and its derivatives (XLFbDP), and by a method using the effect of monochloroacetic acid (MCA) treatment on kidney sections. In proliferative glomerulonephritis (PGN), XLFbs were detected within the capillaries and extension beyond the mesangium was seen in severe PGN. The FRA within the mesangium of minimal or mild PGN was composed of the non-XLFb substance. The FRA within Bowman's space of most PGN had disappeared after MCA treatment, suggesting a non-XLFb substance. The presence of FRA within electron-dense deposits (EDD) suggested that FRA deposits are associated with immune-complex deposits in the glomeruli. 相似文献
32.
Cleavage of human complement component C5 by cysteine proteinases from Porphyromonas (Bacteroides) gingivalis. Prior oxidation of C5 augments proteinase digestion of C5.
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R G Discipio P J Daffern M Kawahara R Pike J Travis T E Hugli J Potempa 《Immunology》1996,87(4):660-667
Since severe periodontitis is characterized by an acute inflammatory response with cellular infiltration and microbial overgrowth, plasma proteins could be exposed to both proteinases and oxidants released from the granulocytes, as well as to proteinases from the microorganisms. When human complement component C5 was digested by cysteine proteinases (i.e. gingipain-R and gingipain-K) from Porphyromonas gingivalis, limited cleavage of the C5 molecule was observed. If C5 was first oxidized by hydroxyl radicals, these gingipains converted modified C5 to fragments that exhibited significantly greater pro-inflammatory activity than did digests of unmodified C5. After cleavage of oxidized C5 by gingipain-R, the digest exhibited measurably greater neutrophil enzyme release and chemotaxis of human polymorphonuclear leukocytes (PMNs) compared with the activities of unoxidized C5 digests. Gingipain-K generates virtually no polarization or chemotactic activity of human PMNs from C5, nor is enzyme release stimulated by these C5 digests. However, when oxidized C5 was digested by gingipain-K, human PMNs were stimulated for polarization, chemotaxis and enzyme release indicating that an active fragment had been generated. Proteolysis of oxidized C5 evokes greater neutrophil activation than does proteolysis of unoxidized protein, a fact which supports the hypothesis that oxidation and proteolysis may be coupled to enhance the destructive effects of the inflammatory process. These results, in which digests of both oxidized and unmodified complement component C5 were evaluated, support the general concept that oxidation and proteolysis may participate cooperatively in amplifying both the severity and duration of the inflammatory reaction. 相似文献
33.
Yosuke Morimitsu Hiroshi Tanaka Shigeaki Iwanaga Masamichi Kojiro 《Pathology international》1993,43(4):204-208
A rare case of an alveolar soft part sarcoma of the uterine cervix in an 8 year old girl is presented. The patient was admitted because of genital bleeding lasting for 7 months. A polypoid tumor, 2times1.5 cm in diameter, was found in her external uterine os and was surgically resected. Microscopically, the tumor consisted of a uniform sheet of tumor cells in the cytoplasm which contained granules and which were stained with periodic acid-Schiff, both before and after the diastase digestion. Alveolar arrangement of the tumor cells was manifested with reticulin silver impregnation. Dense, membrane bound granules were evident at an ultrastructural level in the cytoplasm of the tumor cells. An immunohistochemical examination demonstrated a positive reaction for anti-desmin, anti-myoglobin, anti-HHF35 and anti-neuron specific enolase in the cytoplasm. 相似文献
34.
Abnormal expression of the human CD44 gene in early colorectal malignancy with special reference to variant exon 9 (9v). 总被引:2,自引:0,他引:2
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AIMS: To examine the expression of CD44 variant exon 9 in early colorectal malignancies. METHODS: Formalin fixed, paraffin wax embedded tissue sections from 30 cases of tubular adenoma and 35 cases of adenoma with focal carcinoma of the colon were examined immunohistochemically using a monoclonal antibody (MAb 11.24) directed against CD44-9v. RESULTS: In the normal colorectal mucosa immunoreactivity was confined to the basal part of the crypts and was expressed in less than 10% of crypt cells. CD44-9v was expressed in the superficial part of tubular adenoma with mild atypia in 67% of the cases and in 19% of the tumour cells. The immunoreactivity was observed along the basement membrane in mild atypia, as in the non-neoplastic crypts. In the course of progression to severe atypia the spatial polarity of immunoreactivity was lost, and the extent of CD44-9v expression increased in intensity and in the percentage of positive cases and positive cells. In the carcinomatous lesions of adenoma with focal carcinoma, 94% of the cases and 44% of the tumour cells were positive for CD44-9v protein. CONCLUSION: CD44-9v may be overexpressed at the early stage of colorectal tumorigenesis and this increase continues throughout the course of the disease. 相似文献
35.
Kokubo A Yasuoka Y Nishikitani M Saigenji K Kawahara K 《The Japanese journal of physiology》2005,55(6):317-324
To determine if vasoactive intestinal peptide (VIP) restores neural activity from tetrodotoxin (TTX) blockade, we studied the effects of VIP and related agents on carbachol (Cch)-induced Cl(-) secretion in control-isolated guinea pig distal colon and in that treated with TTX. The short circuit current (I(sc)) increased dose-dependently after serosal applications of Cch (10(-6) - 2 x 10(-5) M) and VIP (5 x 10(-9) - 10(-7) M). But no additive or synergistic increase in I(sc) was observed. Cch- and VIP-induced I(sc) was completely abolished by a serosal application of TTX (10(-6) M). However, a serosal application, not mucosal, of VIP (10(-7) M) and 8-bromo-cAMP (10(-3) M) restored the Cch-stimulated, TTX-inhibited I(sc) by 113% and 75.8%, respectively. Furthermore, mucosal and serosal applications of forskolin (aden late cyclase activator) restored the I(sc) by 43.9% and 65.3%, respectively. The restored I(sc) was completely abolished by atropine (muscarinic receptor antagonist). These results suggest that VIP may restore the cholinergic activity by increasing the level of intracellular cAMP, and that cholinergic neuron is very likely to be responsible for the regulation of Cl(-) secretion at neuroepithelial junctions. The exact mechanism of VIP's effect on the TTX-inhibited epithelial Cl(-) secretion, and its possible usefulness in the treatment of TTX-induced pathophysiological conditions, remain to be determined. 相似文献
36.
Ei Kawahara Yoshio Oda Shogo Katsuda Isao Nakanishi Kunihiko Aoyama Katsuro Tomita 《Virchows Archiv : an international journal of pathology》1991,419(5):373-380
Summary Thickened ligamenta flava obtained from 14 patients with spinal canal stenosis were examined with special reference to type VI collagen. The characteristic histological finding in the thickened area was rupture of normal elastic fibre meshwork with resultant fibrosis which usually appeared hyaline. Using an immunohistological method, collagen types VI, I and III were found to be present in the hyaline matrix. Ultrastructural study revealed many microfilamentous structures of type VI collagen admixed in loosely packed, banded collagen fibres. With differential salt precipitation of pepsin-extracted collagen the existence of type VI collagen was confirmed by SDS-polyacrylamide gel electrophoresis analysis and Western blotting analysis using anti-type VI collagen antibody. Quantification of type VI collagen in pepsin-extracted crude collagen samples by an inhibition enzyme-linked immunosorbent assay showed an increasing amount of type VI collagen in the thickened ligamenta flava compared to the normal ligaments. Thus, increase of type VI collagen is the main contribution to the thickening of the ligamentum flavum. This may represent an adaptational and reparative process associated with disruption of elastic fibres. 相似文献
37.
38.
Aoki Y Saida T Nakano I Saito T Ikeguchi K Urabe T Nishiguchi E Suzuki H Takahashi K Mizuno Y 《Rinsho byori. The Japanese journal of clinical pathology》2002,50(3):308-312
Medullasin levels in granulocytes of patients with neurological diseases and healthy volunteers were determined by the enzyme immunoassay using mouse monoclonal antibodies against human medullasin and o-phenylenediamine-H2O2 as the detection system of the enzyme activity. One hundred twenty-one out of 159 patients with multiple sclerosis (76.1%) showed positive results (above means of normals + 2SD) in this test, while only 16.9% (24/142) of patients with non-inflammatory neurological diseases had positive results. This enzyme immunoassay method for medullasin is considered to be an useful paraclinical test for the diagnosis of multiple sclerosis. 相似文献
39.
Yuji Narita Hideaki Kagami Hiroshi Matsunuma Yosuke Murase Minoru Ueda Yuichi Ueda 《Journal of artificial organs》2008,11(2):91-99
Previous attempts to create small-caliber vascular prostheses have been limited. The aim of this study was to generate tissue-engineered small-diameter vascular grafts using decellularized ureters (DUs). Canine ureters were decellularized using one of four different chemical agents [Triton-X 100 (Tx), deoxycholate (DCA), trypsin, or sodium dodecyl sulfate (SDS)] and the histology, residual DNA contents, and immunogenicity of the resulting DUs were compared. The mechanical properties of the DUs were evaluated in terms of water permeability, burst strength, tensile strength, and compliance. Cultured canine endothelial cells (ECs) and myofibroblasts were seeded onto DUs and evaluated histologically. Canine carotid arteries were replaced with the EC-seeded DUs (n = 4). As controls, nonseeded DUs (n = 5) and PTFE prostheses (n = 4) were also used to replace carotid arteries. The degree of decellularization and the maintenance of the matrix were best in the Tx-treated DUs. Tx-treated and DCA-treated DUs had lower remnant DNA contents and immunogenicity than the others. The burst strength of the DUs was more than 500 mmHg and the maximum tensile strength of the DUs was not different to that of native ureters. DU compliance was similar to that of native carotid artery. The cell seeding test resulted in monolayered ECs and multilayered alpha-smooth muscle actin-positive cells on the DUs. The animal implantation model showed that the EC-seeded DUs were patent for at least 6 months after the operation, whereas the nonseeded DUs and PTFE grafts become occluded within a week. These results suggest that tissue-engineered DUs may be a potential alternative conduit for bypass surgery. 相似文献
40.
伴有肌样/肌纤维母细胞性分化的隆突性皮纤维肉瘤的临床病理分析 总被引:5,自引:0,他引:5
目的 探讨隆突性皮纤维肉瘤(DFSP)中肌样/肌纤维母细胞性分化的本质及其临床病理学意义。方法 采用常规HE切片对124例DFSP进行筛选,对6例伴有肌样/肌纤维母细胞性分化的DFSP病例进行免疫组织化学标记,其中2例加做电镜检测。结果 肌样/肌纤维母细胞性分化多出现在纤维肉瘤型DFSP(FS-DFSP)中,表现为肿瘤周边部或肿瘤内散在性分布的深嗜伊红色小结节或短要束,由梭形细胞组成,细胞多无异型性,核分裂象也罕见,形态上似平滑肌细胞或肌纤维母细胞。免疫组织化学标记显示肌样区域细胞表达α-平滑肌肌动蛋白和肌物质特异性肌动抗原,不表达CD34;电镜观察证实细胞含有质膜下微丝束、局灶性致密体及微胸饮囊泡样结构,与肌纤维母细胞相一致,结论 DFSP中的肌样/肌纤维母细胞性分化可能是间质中肌纤维母细胞增生的结果,并非代表了瘤细胞的真性肌纤维母细胞性分化。 相似文献