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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 and Aims:  Increased numbers and enhanced functions of peripheral neutrophils have been observed in obstructive jaundice. However, the effects of obstructive jaundice on the bone marrow, that is neutrophil production and acquisition of neutrophil chemotactic activity, have been poorly understood. In the present study, differentials of bone marrow cells and chemotactic activity of bone marrow neutrophils were evaluated in bile duct-obstructed rats.
Methods:  Male Wistar rats underwent either bile duct obstruction for 10 days or bile duct obstruction for 4 days followed by 6 days' internal biliary drainage. Differentials of peripheral blood and bone marrow cells were sequentially determined. Chemotactic activity of peripheral and bone marrow neutrophils was evaluated with a modified Boyden method using interleukin-8 (recombinant rat Gro-β) as a chemoattractant.
Results:  Numbers of peripheral neutrophils significantly increased after bile duct obstruction. Significant increases in the myeloid/erythroid (M/E) ratio of bone marrow cells were observed after bile duct obstruction. The neutrophil proliferative pool (promyelocytes and myelocytes) increased initially, followed by an increased neutrophil storage pool (metamyelocytes, bands, and segmented neutrophils). The M/E ratio as well as the neutrophil proliferative and storage pools normalized after internal biliary drainage. Chemotactic activity was enhanced in both peripheral and bone marrow neutrophils after bile duct obstruction, and enhanced chemotaxis was alleviated with internal biliary drainage.
Conclusion:  The present results strongly suggest the principal role of the bone marrow in increasing the number of neutrophils and their chemotactic activity during obstructive jaundice.  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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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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The effects of camostat mesilate, a synthetic serine protease inhibitor on gastric microcirculation and active oxygen species generated by leucocytes from the gastric and jugular veins in the early period after thermal injury were assessed. Male Wistar rats were anaesthetized and a 30% full skin-thickness dorsal burn was inflicted. Camostat mesilate (100 mg/kg) was dissolved in distilled water and administered orally to rats 40 min before thermal injury (the camostat group). The control animals (the vehicle group) were administered distilled water orally. Rolling leucocytes as well as Monastral blue B deposits in venules were observed using in vivo microscopy. Active oxygen species were measured by chemiluminescence. Camostat mesilate decreased the total length of gastric erosion, venular deposits of Monastral blue B, and rolling of leucocytes in venules, and relatively increased luminol-dependent chemiluminescence activity generated by zymosan-stimulated leucocytes 15 min after thermal injury. These results suggest that serine proteases are involved in the formation of gastric erosions and gastric microcirculatory disturbance in the early period after thermal injury.  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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