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BACKGROUND: It is suggested that the highly cation-charged fraction of the IgG and IgG3 subclasses may play a pathogenic role in lupus nephritis. In contrast, immunoadsorbent therapy using a sodium dextransulfate fixed cellulose gel column-low invasive selective immunoadsorbent apheresis therapy (SDSC-IAT) has been applied to lupus nephritis with favorable results. However, elimination using pathogenic IgG by SDSC-IAT has never been investigated. METHOD: Two patients with diffuse proliferative lupus nephritis were treated using SDSC-IAT concomitant with immunosuppressive therapy. The eluates from the SDSC, and the patients' serum obtained before and just after SDSC-IAT were subjected to an IgG charge analysis using isoelectric focusing and immunoblotting, and also to laser nephelometry assay, which is used for measuring IgG subclass concentration. Indirect immunofluorescence staining was performed to detect IgG subclass deposition in the glomerulus. RESULTS: Both of the patients had an immediate decrease in anti-double-strand DNA antibody and in the circulating immune complex with a following clinical improvement. Repeated biopsies demonstrated improvement of glomerular lesions with a marked reduction of IgG and C3 deposition. The IgG of the SDSC eluates consisted of highly cation charged (isoelectric points: 9-10) fractions. In addition, IgG3 was specifically removed from the patients' serum using an SDSC among the IgG subclasses. The subclass of deposited IgG in the glomeruli showed IgG3 predominance. CONCLUSION: SDSC-IAT specifically removed the highly cation charged fractions of IgG and IgG3 from the patients' serum and the elimination of these fractions may have resulted in clinical improvement.  相似文献   
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SUMMARY: Inhibition of mevalonate synthesis by several statins has been shown to suppress DNA synthesis in glomerular mesangial cells. In the present study, we investigated the effect of a new statin, cerivastatin, on fetal calf serum (FCS)-induced DNA synthesis of cultured rat mesangial cells. Cultured rat mesangial cells were stimulated by 10% FCS in the presence or absence of cerivastatin and mevalonate. 5-bromo-2-deoxyuridine (BrdU) incorporation was used to assess DNA synthesis. the present study showed that 10% FCS caused marked stimulation of DNA synthesis in the mesangial cells. Cerivastatin inhibited FCS-stimulated BrdU incorporation in a dose-dependent manner. IC50 was approximately 1 umol/L. Exogenous mevalonate, farnesyl pyrophosphate and geranylgeranyl pyrophosphate significantly prevented the inhibitory effect of cerivastatin on DNA replication. It appears that cerivastatin, by inhibiting the synthesis of mevalonate, may suppress DNA synthesis in the mesangial cells.  相似文献   
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Background: Colonic pseudolipomatosis is rare and the pathogenesis is controversial. The purpose of the present paper was to clarify endoscopic and histological characteristics of colonic pseudolipomatosis and to discuss the etiology. Methods: A total of 15 lesions from 14 patients was reviewed. They were able to be histologically classified into two groups on the basis of variety in size of the vacuoles: Group A, the ratio of largest vacuole to smallest vacuole in size is less than three, Group B, the ratio is more than four. Results: Four of 15 lesions were group A, and were endoscopically polypoid or flat lesions covered with normal‐looking mucosa. They were microscopically characterized by (i) predominant location in the upper portion of the lamina propria; (ii) no submucosal involvement; (iii) less variation in vacuolar size; and (iv) no association with lymph follicles. The vacuoles of group A contained proteinaceous materials in two of four lesions. Group B (11 lesions) had small elevated mucosa with normal‐looking surface or non‐elevated reddish mucosa. Microscopically, the lesions were mainly located in the lower portion of the lamina propria, occasionally also in the submucosa, had variable‐sized vacuoles, and were related to lymph follicles. Conclusion: It is suggested that the vacuoles in group A contain fluid, and may indicate an abnormal stagnation of interstitial fluid. Microscopic appearance of group B is essentially similar to that of pneumatosis coli. It is thought that group B probably results from penetration of gas from the crypts into the mucosa during colonoscopy. It is unclear why group B had a preference for ileocecal valve and an association with lymph follicles.  相似文献   
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Dose-Related Effects of the Hepatocarcinogen, Wy-14,643, onPeroxisomes and Cell Replication. WADA, N., MARSMAN, D. S.,AND POPP, J. A. (1992). Fundam. Appl. Toxicol. 18, 149–154. The dose and time dependency of peroxisome proliferation andhepatocyte replication was evaluated in the liver of rats fedthe peroxisome proliferator and hepatocarcinogen, Wy-14,643.Male F344 rats were fed NIH07 diet blended with Wy-14,643 at0, 5, 10, 50, 100, or 1000 ppm for 1, 3, 6, or 13 weeks. Hepatomegalywas induced by Wy-14,643 at all doses and at all time points.Peroxisome proliferation was present in rats fed 5 ppm Wy-14,643as early as 1 week, as determined by the peroxisome-specificNAD+ reduction of palmitoyl CoA (PCO) and the peroxisome-associatedactivity of carnitine acetyltransferase (CAT) (5-and 11-foldover control, respectively). The elevations of PCO and CAT weredose-dependent from 5 to 50 ppm and then plateaued from 50 to1000 ppm throughout the treatment period. Hepatocellular replication,evaluated by nuclear histoautoradiography ([3H]thymidine labeling,6-day infusion), was increased in all Wy-14,643 dose groupsafter 1 week of treatment (5 ppm, 4-fold; 10 ppm, 5-fold; 50ppm, 13-fold; 100 ppm, 12-fold; and 1000 ppm, 13-fold over controls).However, in 5 and 10 ppm groups this cell replication returnedto control levels by 3 weeks. In contrast, 50, 100, and 1000ppm groups had sustained increases in cell replication up to13 weeks (13 weeks: 6-, 7-, and 9-fold over controls, respectively).We have demonstrated that Wy-14,643 can induce peroxisome proliferationat 5 ppm, a dose 200 times lower than the dose shown to be highlyhepatocarcinogenic in rats (100% incidence by 60 weeks). Incontrast, 50 ppm was identified as the minimal dose which inducedsustained cell replication in rat liver. These data show thatperoxisome proliferation can be dissected from sustained cellreplication for correlating either peroxisome induction or cellreplication with tumor formation. These results provide importantinformation that can be used to design carcinogenicity experimentsto test if peroxisome proliferation and/or chronic enhancementof cell replication predictive risk factors for hepatocarcinogenieity.  相似文献   
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To clarify the pathogenesis of the widely known but obscuresyndrome of sudden death with hepatic fatty metamorphosis observedin alcohol abusers, we have scrutinized both the clinical andpathological data of 11 subjects who died under such circumstancesbetween 1987 and 1993. Death followed several days of uninterrupteddrinking often with little dietary intake. The notable clinicalfeatures on arrival at the emergency room were disturbance ofconsciousness (11/11), hypotension (47/6), hypothermia (3/5),hypoglycaemia (8/11), metabolic acidosis (6/6), renal dysfunction(11/11), and hyperammonaemia (5/5). The common hepatic pathologywas the extensive appearance of numerous microvesicular fattydroplets in the hepatocytes together with varying degrees ofmacrovesicular fatty change; four subjects had an underlyingcirrhosis. Death undoubtedly results from a variety of metabolicdisturbances triggered by the combination of massive ethanolintake and starvation. The appearance of extensive microvesicularfatty change superimposed on macrovesicular fatty change wasconsidered to be an associated phenomenon  相似文献   
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AIM: The aim of the present study was to investigate the safety and efficacy of endoscopic laser therapy for transitional cell carcinoma (TCC) of the upper urinary tract. METHODS: Tumors of the renal pelvis and ureteropelvic junction were detected by ureteroscopy. The tumors were subjected to biopsy, and after TCC was diagnosed, endoscopic laser therapy (Neodymium-YAG and Holmium-YAG) was conducted using a 6.9 Fr. flexible ureterorenoscope. RESULTS: From January 1997 to April 2002, six patients underwent ureteroscopic treatment. Tumor grade was 1 in four patients and 2 in two patients. Average tumor size was 1.45 cm. Endoscopic treatment was chosen for two patients because of the high medical risk associated with open surgery. Another patient underwent diagnostic ureteroscopy, followed immediately by endoscopic treatment. A further three patients elected to undergo ureteroscopic treatment. One patient with large (3 cm), multifocal and incompletely treated tumors died of metastatic disease 22 months after the initial operation. One patient requested nephroureterectomy one month after endoscopic treatment, and pathological examination of the resected specimen revealed no tumor. The other four patients have been followed up for a mean period of 14 months after initial treatment. Recurrence occurred in one patient, and was successfully treated by repeat endoscopic resection. None of the patients required blood transfusion or emergency open surgery. CONCLUSION: Ureteroscopic treatment of small, localized, low-grade TCC of the upper urinary tract is now a safe and feasible alternative to nephroureterectomy in selected patients.  相似文献   
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Effect of relaxation training on cardiac parasympathetic tone   总被引:8,自引:0,他引:8  
To examine the hypothesis that the relaxation response is associated with an increase in cardiac parasympathetic tone, the frequency components of heart rate variability during relaxation training were investigated in 16 college students. Electrocardiograms and pneumograms were recorded during a 5-min baseline period followed by three successive 5-min sessions of the autogenic training (relaxation) or by the same periods of quiet rest (control), while subjects breathed synchronously with a visual pacemaker (0.25 Hz). Although neither the magnitude nor the frequeney of respiration showed a significant difference between relaxation and control, the amplitude of the high-frequency component of heart rate variability increased only during relaxation (p= .008). There was no significant difference in the ratio of the low-frequency (0.04–0.15 Hz) to the high-frequency amplitudes. The increased high-frequency amplitude without changes in the respiratory parameters indicates enhanced cardiac parasympathetic tone. Thus, our results support the initial hypothesis of this study. Enhanced cardiac parasympathetic tone may explain an important mechanism underlying the beneficial effect of the relaxation response.  相似文献   
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