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1.
Air-pouch-type inflammation was induced by injecting sodium carboxymethyl cellulose solution containing leukotriene C4 (LTC4, 3.20 x 10(-7) M, 0.2 micrograms/ml) and prostaglandin E2 (PGE2, 5.68 x 10(-6) M, 2.0 micrograms/ml), platelet-activating factor (PAF, 1 x 10(-6) M, 0.52 micrograms/ml), or 12-O-tetradecanoyl phorbol 13-acetate (TPA, 1.62 x 10(-6) M, 1.0 micrograms/ml) into an air pouch made on the dorsum of rats. Vascular permeability and tissue edema formation were significantly increased by injecting the phlogogen solution. The histamine level in the pouch fluid was dramatically increased by injecting TPA but not by LTC4 and PGE2, or PAF. Injection of isoproterenol or procaterol with the phlogogen solution produced dose-dependent suppression of both vascular permeability increase and tissue edema formation. However, the TPA-induced increase in the histamine level was not suppressed in parallel with the decrease of vascular permeability or tissue edema formation. These results indicate that beta-agonists suppress vascular permeability response and local tissue edema formation not by inhibiting mast cell degranulation, but by inhibiting the reactivity of the local vasculature to chemical mediators such as arachidonate metabolites, PAF, and histamine and serotonin released from mast cells.  相似文献   
2.
Accumulation and declination of chlordane congeners in mice   总被引:1,自引:0,他引:1  
A metabolic experiment involving technical chlordane in mice was carried out in vivo by single and repeated oral administration. In the single oral dose group, residues of trans- and cis-chlordane in mouse whole body showed a maximum content at 5 hours after administration; thereafter, the body content decreased rapidly. For other congeners, the residues of trans- and cis-nonachlor reached a maximum at 10 hours, the residual levels forming a plateau. The intermediate metabolite oxychlordane was detected 1 hour after the administration of technical chlordane, the content in the mouse body increasing with time. In the repeated oral dose group, although technical chlordane was administered repeatedly, increases in trans- and cis-chlordane content were not observed for 29 days. On the other hand, the nonachlor and oxychlordane content increased gradually throughout the observation period. These findings suggest that the accumulation of nonachlors and oxychlordane in the animal body must be high and sufficient attention must be paid to their toxic effect.  相似文献   
3.
Patients on long-term hemodialysis (HD) are known to develop amyloid osteoarthropathy, evidenced as cystic radiolucencies on X-rays of the affected joints. To study the relationship between cystic radiolucencies and amyloid osteoarthropathy in 394 patients, we classified the severity of the cystic radiolucencies seen in the wrist joint on a 4-point scale and evaluated the association between lesion severity (grade) and several parameters. Biopsy was performed in 8 patients with 11 bone cysts of the wrist joint who had been operated for carpal tunnel syndrome. HD for 10 years or longer, age 50 or older and the presence of carpal tunnel syndrome were associated with severe cyst rating. There was no association between lesion grade and serum level of PTH-C, aluminum or beta 2-microglobulin (B2M). Ten of the 11 biopsied bone cysts in 8 patients with carpal tunnel syndrome demonstrated amyloid deposits which reacted with B2M. We conclude that a cystic radiolucency observed in the wrist joint of a patient undergoing HD indicates the deposition of amyloid. The cyst grade provides a useful marker for the severity of amyloid osteoarthropathy in HD patients.  相似文献   
4.
5.
The present study investigated the influence of hydrostatic prssure on the exprssion of cytokines and heat shock protein 70 in a chondrocyte-like cell line. Chondrocyte-like cells (HCS-2/8) were exposed to hydrostatic pressur by a special pressure apparatus. Total RNA for cytokines (interleukin-1β, basic fibroblast growth factor, insulin-like growth factor-I, and transforming growth factor-β1) and for heat shock protein 70 was extracted and was analyzed by a polymerase chain reaction method and Northern blotting. An assay for incorporation of [35S]sulfate was performed to assess proteoglycan synthesis. The expression of transforming growth factor-β1 mRNA was enhanced after exposure to 5 Mpa of hydrostatic prssure and was reduced after 50 Mpa, whereas the expression of heat shock protein 70 was enhanced following exposure to 50 Mpa of hydrostatic pressure. The incorporation of [35S]sulfate into the cultured cells increased following exposure to 1-5 Mpa of hydrostatic pressure and decreased following 10-50 Mpa of pressure. These results suggest that hydrostatic pressure at physiologic levels enhances the expression of transforkming growth factor-β mRNA in addition to increasing proteoglycan synthesis in chondrocytes and that excessively high hydrostatic pressure reduces the expression of transforming growth factor-β1 mRNA and increases the expression of heat shock protein 79 mRNA while decreasing proteoglycan synthesis.  相似文献   
6.
In basilar artery thrombosis, hemiparesis without obvious brainstem signs may precede the tetraplegia with coma or a locked-in state. This premonitory hemiparesis was called as "herald hemiparesis" by Fisher (1988). Its early detection is important because immediate anticoagulant therapy may prevent its evolution. We reported two patients with such hemiparesis. The first case was a 71-year-old diabetic and hypertensive man who was admitted because of right hemiparesis, dysarthria and decreased spontaneous speech. Initially, his symptoms looked like those of a left cerebral lesion. CT scans revealed no fresh cerebrovascular lesion. A few hours later, a myoclonic movement appeared in his left lower limb, and right MLF syndrome developed. We thought he had basilar artery thrombosis and we started intravenous administration of heparin. But he developed tetraplegia with locked-in state. The second case was a 76-year-old diabetic and hypertensive man with a confusional state, right hemiparesis, dysarthria and conjugate gaze deviation to left. After admission, he rapidly became comatose and developed respiratory arrest. CT scans revealed low density areas in the brainstem, cerebellum and the occipital lobe. He died ten days later. Early detection of herald hemiparesis is by no means easy. However, severe dysarthria and myoclonic jerks in a patient with hemiparesis should be considered as warning signs to indicate the herald hemiparesis with subsequent severe brainstem infarction.  相似文献   
7.
ICAM-1 plays an important role in inflammatory diseases. We analysed ICAM-1 expression on BAL fluid cells and measured soluble ICAM-1 (sICAM-1) concentrations in sera and BAL fluids from patients with extrinsic allergic alveolitis (EAA). We found significantly increased cellular ICAM-1 expression on BAL fluid lymphocytes and alveolar macrophages, and significantly increased values of circulating and BAL fluid sICAM-1 in EAA patients compared with controls. Successive measurement showed prompt decrease of both sICAM-1 values in EAA patients during periods when antigen exposure was prevented. In BAL fluids from EAA patients, sICAM-1 values significantly correlated to neutrophil and ICAM-1+ lymphocyte counts. In EAA patients, circulating and BAL fluid sICAM-1 values has significant negative correlations to values of carbon monoxide diffusing capacity and to time intervals between last episode and sample collection. However, these values had significant positive correlation to values of alveolar-arterial oxygen pressure difference. In EAA, antigen exposure appears to induce cellular ICAM-1 expression on BAL fluid cells, and also appears to up-regulate shedding of ICAM-1 in the alveolar lining fluid and in the circulation. The sICAM values appear to reflect disease activity of EAA.  相似文献   
8.
Testes of 8-week-old male Syrian hamsters which were inoculated intraperitoneally with 10(5) plaque-forming units of the D variant of encephalomyocarditis virus (EMC-D) were examined virologically and histologically. Viral replication was detected from 1 day post inoculation (1 DPI), became more prominent 3 DPI, and was no longer demonstrated 7 DPI. The weight of testis decreased in course of time and it was about 2% of that of control 6 weeks post inoculation (6 WPI). Histopathologically, degeneration and/or necrosis of germinal cells and spermatogonia were observed in many seminiferous tubules of all hamsters 3 DPI. At 7 DPI, luminal obstruction by cellular debris and subsequent replacement of them by mesenchymal cells were common in mildly atrophic tubules surrounded with inflammatory cells. Thereafter, atrophy of seminiferous tubules became severer with the lapse of time and, in addition to plasma cell infiltration, apparent increase in the number of Leydig cells was found in the interstices. No regenerative signs of germinal epithelia were detected by 6 WPI. This is the first report of EMC virus-induced orchitis.  相似文献   
9.
A coupling sugar preparation (sucrose-free [CSSF]), which contains a mixture of sugars, oligosaccharides, and oligosaccharides terminated at the reducing end by sucrose, served as a substrate for growth and acid production by Streptococcus mutans 6715. However, CSSF was a poor substrate for cellular aggregation, glucosyltransferase activity, plaque formation, and adherence of cells to glass surfaces. In the presence of sucrose, CSSF inhibited glucosyltransfer activity and adherence of cells. The substitution of CSSF for sucrose in a rat diet significantly reduced caries score. Furthermore, rats fed diets containing sucrose and CSSF had significantly fewer carious lesions than did rats fed a sucrose diet.  相似文献   
10.
 To improve our understanding of the role of extracellular matrix (ECM) proteins and integrins during the processes of granuloma formation in sarcoidosis, we examined the distribution of ECM proteins and the expression of integrins in sarcoid lymph nodes by immunohistochemical methods. We also examined the expression of transforming growth factor-β1 (TGF-β1), which is one of major regulators for synthesis of ECM proteins. Most ECM proteins were detected in the periphery of the granulomas in a concentric pattern, and fibronectin was diffusely detected from an early to a regressive stage. Compared with normal lymph nodes, most β1-integrin subfamilies (α1, α4, α5 and α6) were more strongly expressed on lymphocytes around the granulomas. Epithelioid cells exhibited strong expression of the α5 molecule. Fibroblasts exhibited the expression of the α2 and α5 molecules surrounding ECM proteins. The α5β1 molecule had a distribution similar to that of fibronectin. TGF-β1 was detected in epithelioid cells throughout the various evolutional stages and its expression was especially marked in mature granulomas. Interaction of fibronectin and the α5β1 molecule may have an important role in the process of formation of sarcoid granuloma. The expression of TGF-β1 may be involved in the regression of sarcoid granuloma by initiating fibrosis and atrophy of epithelioid cells. Received: 2 December 1997 / Accepted: 19 February 1998  相似文献   
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