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51.
Cleavage of human complement component C5 by cysteine proteinases from Porphyromonas (Bacteroides) gingivalis. Prior oxidation of C5 augments proteinase digestion of C5. 下载免费PDF全文
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
52.
Issei Nishimori Nobuo Moriyama Nobuo Tsuda Akira Shimomura 《Pathology international》1974,24(4):551-567
A 19-year-old female belonging to a family of Alport's syndrome was autopsied and her kidneys were examined in detail light and electron microscopically. The basement membrane was examined chiefly and the laminated thickening and/or splitting, looseness, irregularity and rail-like appearance of lamina densa were found in the glomerular, Bowman's capsular, tubular and interstitial capillary basement membranes. These findings were strongly suggestive of Alport's syndrome, whether or not the particles are seen in the basement membrane. In addition, Japanese reports on Alport's syndrome (total 48 families) were summarized and renal lesions were examined in comparison. It has been said that the prognosis is worse in the male than in the female, but according to our Investigation on case reports in Japan, the prognosis showed no difference between male and female. 相似文献
53.
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 下载免费PDF全文
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
54.
Kenichiro Karasawa Nobuo Sugiura Yusuke Hori Sakaru Suzuki Junichi Onaya Katsukiyo Sakurai Koji Kimata 《Clinical & experimental metastasis》1997,15(2):83-93
Chondroitin sulfate dipalmitoylphosphatidylethanolamine (CS-PE), when immobilized onto substratum, inhibited the adhesion of B16F10 mouse melanoma cells to fibronectin-coated dishes (anti-adhesion activity). CS-PE showed the most potent anti-adhesion activity for the melanoma cells among various GAG-PEs. CS-PE also inhibited the adhesion of B16F10 cells to Matrigel and the invasion of the cells into Matrigel. In the in vivo system of experimental metastasis, administration of B16F10 cells with CS-PE into C57BL/6 mice significantly inhibited lung metastasis. The inhibition degree of CS or hyaluronic acid-PE was lower than CS-PE. CS-PE administered intravenously into mice before the injection of B16F10 cells also inhibited metastasis. Pretreatment of B16F10 cells with CS-PE caused some but a lower degree of inhibition. When CS-PE was injected intravenously into mice, more binding in the lung was found than when CS was injected. CS-PE but not CS inhibited the retention in the lung of fluorochrome-labeled B16F10 cells when injected intravenously into mice. Since there was no significant effect of CS-PE on the viability and growth of B16F10 cells, the results suggest that CS-PE immobilized onto the subendothelial matrix may prevent melanoma cells from adhering to the subendothelial substrata of lung capillaries and inhibit subsequent invasion processes of metastasis. 相似文献
55.
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
56.
Nobuo Tsuda Paritosh Roy Chowdhury Tomayoshi Hayashi Masanobu Anami Masachika Iseki Shigehiko Koga Fukuzo Matsuya Hiroshi Kanetake Yutaka Saito Yoshio Horita 《Pathology international》1997,47(11):778-783
Primary renal angiosarcoma is very rare. To our knowledge, only 15 cases have been reported to date. A 77-year-old Japanese man with a unilateral kidney presented with massive hematuria followed by renal failure. A renal tumor was suspected and a left nephrectomy was performed. The histopathological diagnosis was angiosarcoma of the kidney. A hemorrhagic tumor measuring 10 × 5 cm and clotted blood was found in the modularly area. The atypical tumor cells had a sinusoidal and solid appearance, and showed Immunohistochemically positive reactions for some of the endothelial markers. The patient died about 21 months after the nephrectomy and the autopsy revealed massive metastases to the liver and retroperitoneum. One of the differential diagnoses of the case was anglomyolipoma, because the tumor cells were relatively bland in their histological appearance with entrapped fat cells in the pelvic area. Fifteen case reports with titles that included the term 'hemangiosarcoma/anglosarcoma', 'hemangioendothelloma/endothelloma' or 'vascular sarcoma' of the kidney were reviewed and compared to the present case. 相似文献
57.
Koh Nakazawa Nobuo Itoh Hui-Jun Duan Yuichi Komiyama Hidekazu Shigematsu 《Pathology international》1992,42(9):662-666
A 73-year-old Japanese man with a history of partial gastrectomy due to gastric cancer 4 years previously was admitted because of intermittent fever. The patient developed abdominal pain, erythema, and myalgia in addition to the fever during the final clinical course, and died of acute heart failure. Autopsy disclosed atrophy of the left lobe of the liver and acute myocardial infarction. Neither metastasis nor recurrence of the cancer was observed. Small and medium-sized arteries of the visceral organs showed various stages of necrotizing vasculitis with narrowing of the lumina. The vasculitis was most prominent in the left lobe of the liver and in the heart. Narrowing of the portal vein due to portal tract inflammation in addition to vasculitis of the hepatic arteries may have induced ischemia and infarction, which had resulted in atrophy of the left hepatic lobe. Acta Pathol Jpn 42: 662–666, 1992. 相似文献
58.
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
59.
Fu J Hato M Ohmae H Matsuoka H Kawabata M Tanabe K Miyamoto Y Leafasia JL Chinzei Y Ohta N 《Parasitology research》2000,86(5):345-351
We analyzed the relationships between levels of antibody specific for merozoite surface glycoprotein-1 (MSP1) of Plasmodium falciparum and clinical manifestations in humans. We prepared recombinant MSP1 proteins representing block 3 (M3), block 6 (M6), blocks
1–6 (M1/6), and block 17. When we divided the slide-positive individuals in Guadalcanal into symptomatic and asymptomatic
groups, the former group showed lower IgG levels against M6 and block 17, but not against M3, than did the asymptomatic group
(P < 0.01). The possibility of nonspecific suppression was unlikely, given that the levels of antibody against poliomyelitis
virus observed in the two groups were almost the same. Among the IgG subclasses tested, production of cytophilic IgG3 seemed to be dominant. When we analyzed epitopes recognized by antibodies against block 17, a peptide (SSSNFLGIS) was preferentially
recognized by sera from asymptomatic individuals. These results suggest that clinical symptoms occurring during falciparum
malaria seem to be associated with the development of levels of antibody against particular epitopes on MSP1, which is under
the control of an immunoregulatory mechanism.
Received: 1 October 1999 / Accepted: 21 October 1999 相似文献
60.
Nobukatsu Nemoto Yu Nagase Jiro Abe Hiroshi Matsushima Yasuo Shirai Nobuo Takamiya 《Macromolecular chemistry and physics.》1995,196(7):2237-2249
Side-chain functionalized polysiloxanes were prepared via polymer-analogous esterification of poly[(3-chloroformylpropyl)methylsiloxane] with 4-(4-hydroxyphenylazo)nitrobenzene ( P1 ), 4-[4-(ω-hydroxyalkyloxy)phenylazo]nitrobenzene ( P2 – P4 ), 4-{4-[N-(2-hydroxyethyl)-N-methyl]anilinoazo}nitrobenzene ( P5 ), 4-(4-hydroxypiperidino)nitrobenzene ( P6 ), or 4-[4-(2-hydroxyethyl)piperidino]nitrobenzene ( P7 )., P1 , P3 , P4 and P5 exhibit liquid crystallinity, as deduced from differential scanning calorimetry, polarized microscopic observations and X-ray diffraction measurements. The liquid-crystalline phase of P1 and P5 is a nematic phase, and that of P3 and P4 is a smectic one. The second harmonic generation (SHG) measurement of a spin-coated film of P1 was carried out by the Maker fringe method using a Q-switched Nd:YAG laser (1064 nm). The SHG profile after the heat treatment of a spin-coated film suggests a perpendicular orientation of the mesogenic molecules to the glass substrate. The SH light intensity of a corona-poled film was 20-fold higher than that of a film which was only heated, though no differences were observed in their UV-vis absorption spectra. These findings suggest that the mesogenic-molecular dipole moments are aligned to the same direction in the crystalline or liquid-crystalline phase by a poling treatment. 相似文献