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31.
32.
Autophagy has multiple physiological functions, including protein degradation, organelle turnover and the response of cancer cells to chemotherapy. Because autophagy is implicated in a number of diseases, a better understanding of the molecular mechanisms of autophagy is needed for therapeutic purposes, including rational design of drugs. Autophagy is a process that occurs in several steps as follows: formation of phagophores, formation of mature autophagosomes, targeting and trafficking of autophagosomes to lysosomes, formation of autolysosomes by fusion between autophagosomes and lysosomes, and finally, degradation of the autophagic bodies within the lysosomes. It has been suggested that autophagosome formation is driven by molecular motor machineries, and, once formed, autophagosomes need to reach lysosomes, enriched perinuclearly around the microtubule‐organizing centre. While it is recognized that all these steps require the cytoskeletal network, little is known about the mechanisms involved. Here we assessed the role of cytoplasmic dynein in the autophagic process of human glioma cells to determine the part played by dynein in autophagy. We observed that chemical interference with dynein function led to an accumulation of autophagosomes, suggesting impaired autophagosome‐lysosome fusion. In contrast, we found that overexpression of dynamitin, which disrupts the dynein complex, reduced the number of autophagosomes, suggesting the requirement of the dynein‐dynactin interaction in the early membrane trafficking step in autophagosome formation. These results suggest that dynein plays a variety of crucial roles during the autophagic process in glioma cells.  相似文献   
33.
The apparatus for the respiratory function test have recently made a great progress and become very easy to handle owing to the development of computer technology and medical ordering system. However, the respiratory function tests depend its result on the cooperation of patients. Thus, it is important for the medical technician to obtain the maximum efforts and cooperation of the patients in the testing. In the sense, the standardization of the testing should be done urgently regarding procedures, softwares, hardwares and maintenance of apparatus. In the future perspectives, we would like to emphasize following 3 points. First, more noninvasive and sophisticated testing methods and instruments should be developed, since the patients' age will become more and more old and vigorous active cooperation may not be possible for the assessment of respiratory function. The testing for the transplantation of lung should also be developed. Second, the development of screening test and its performance for the routine medical check for the local inhabitants have been important for the early detection, treatment, and follow up of respiratory diseases. Finally, the medical technician should be prepared so that the testing is available when it is needed.  相似文献   
34.
We report a case of selenium deficiency in a patient with Crohn's disease on long-term total parenteral nutrition (TPN). She manifested lassitude of the legs, discoloration of the nail beds, and macrocytosis. Since her plasma selenium level was found to be below the measurable level, we diagnosed this case as selenium deficiency. After intravenous administration of sodium selenite, her symptoms were reversed. Careful attention should be paid to selenium deficiency when a patient receives long-term TPN; supplementary administration of selenium via TPN may be required because selenium is often not routinely added to TPN formulations.  相似文献   
35.
The relationship between age, heavy metal levels, and a heavy-metal binding protein, metallothionein (MT), in the liver and kidney of the harbor seal (Phoca vitulina) was studied. The cadmium (Cd) level in the liver and the Cd, inorganic mercury (I-Hg), and zinc (Zn) levels in the kidney were increased with body length, suggesting an age-related accumulation of these metals. The MT levels determined by an MT radioimmunoassay showed concentrations of 240 +/- 139 micrograms/g in the liver and 343 +/- 219 micrograms/g in the kidney. These MT levels were shown to be correlated with age. The statistically significant relationship of the MT levels with the levels of Cd and Zn in the liver and those of Cd, Zn, and I-Hg in the kidney suggested that the protein is responsible for the sequestration of these metals as already observed in terrestrial animals.  相似文献   
36.
The amounts of sorbitol (SOR) excreted in 24-h urine were determined on two groups, i.e., diabetic and nondiabetic patients, using an improved method in which ion exchange resin column processing was applied, and these levels were compared with SOR levels in whole blood. Urinary SOR concentration was also determined in diabetic and normal rats in the same manner and its relationship to aldose reductase (AR) activity in whole blood was investigated. Changes in SOR levels in urine and whole blood were compared in diabetic rats after administration of an AR inhibitor (ARI). Whole blood SOR levels and urinary SOR excretion were significantly higher in diabetic patients than in nondiabetic patients. The same results were obtained in the animal models. In diabetic rats, the urinary SOR excretion was about five times higher than that in control rats, and the AR activity in whole blood was also significantly higher. The increase in urinary SOR excretion and whole blood SOR levels, as well as AR activity, in blood in the diabetic state was inhibited by ARI administration. The influence of the diabetic state and the efficacy of the ARI were more marked in urinary SOR excretion than in whole blood SOR levels. These data indicate that determinations of urinary SOR excretion and AR activity are easily measurable and of benefit to assessing the diabetic condition.  相似文献   
37.
BACKGROUND/AIMS: The overall outcome of T2 gallbladder carcinoma has not been favorable, although there is a modest hope for long-term survival after radical resection. The aim of this study was to examine factors influencing postoperative disease-free survival of patients with T2 gallbladder carcinoma to clarify optimal treatment. METHODOLOGY: Of 53 patients with gallbladder carcinoma who had undergone surgical resection from 1985 to 2000, 22 had T2 carcinoma histologically proved. The significance of variables for disease-free survival was examined retrospectively by the Kaplan-Meier method and the log-rank test. RESULTS: There were 16 patients with stage II (T2N0M0), 6 with stage III (T2N1M0) disease. Eleven patients were treated by extended cholecystectomy with resection of the extrahepatic bile duct, 10 patients underwent extended cholecystectomy without resection of the extrahepatic bile duct, and 1 patient underwent cholecystectomy. All patients underwent lymph node dissection in the hepatoduodenal ligament, below the pancreatic head, and along the common hepatic artery. Lymph node metastasis was present in 6 patients. Lymphatic, venous, and perineural invasions were found in 9, 4, and 4 patients, respectively. The absence of lymphatic invasion was a significant factor related to good postoperative disease-free survival (5-year disease-free survival rate, 88.9% vs. 31.3% in the presence of lymphatic invasion). Lymph node, venous, or perineural invasion, and surgical procedure were not significant factors to good postoperative disease-free survival. CONCLUSIONS: For patients with T2 gallbladder carcinoma, the presence of lymphatic invasion is an unfavorable prognostic indicator that calls for additional treatment after radical surgery.  相似文献   
38.
Abstract: We examined whether aggressive lipid lowering using low-density lipoprotein (LDL) apheresis could prevent restenosis after percutaneous transluminal coronary angioplasty (PTCA). Fifteen patients with 17 lesions underwent LDL apheresis once within a week before and after PTCA and thereafter every 2 or 3 weeks (apheresis group) for about 4 months. The control group consisted of 17 patients with 17 lesions. No patients received additional lipid lowering drugs after PTCA. In the apheresis group, the time interval means of the total and LDL cholesterol levels were significantly lower than those in the control group whereas no significant differences were found between the 2 groups regarding the mean percent diameter stenosis or minimal lumen diameter before and after PTCA and at follow-up. The restenosis rate was 29.4% in the apheresis group and 47.1% in the control group. The restenosis rate tended to be slightly lower in the apheresis group. The overall results, however, indicated that aggressive lipid lowering does not prevent restenosis.  相似文献   
39.
The efficacy of interferon- therapy in the treatment of chronic hepatitis C is still limited. A combination therapy of interferon- with ursodeoxycholic acid (UDCA) was tested for its efficacy in the treatment of chronic hepatitis C by a randomized controlled study. Eighty consecutive Japanese patients with chronic hepatitis C were randomly divided into two groups: one group was treated with interferon- (group A,n=40) and the other with a combination of interferon- and UDCA (group B,n=40). In both groups, human interferon- (6 million units per day) was intramuscularly injected daily for 2 weeks and then three times a week for 22 weeks: this 24-week period was followed by 24 weeks of observation. In group B, UDCA was also administered, daily at a dose of 600mg orally, from the beginning of the interferon therapy and administration was continued for 48 weeks. The rates for ALT normalization and clearance of hepatitis C virus (HCV) viremia at the end of the 24-week interferon therapy were similar for groups A and B (58% vs 60% and 55% vs 48%, respectively). At the end of the 24-week follow-up, the sustained normalization rates for ALT levels for the two groups were not different (35% vs 43%), while the rate of clearance was higher in group B (40%) than in group A (23%), but the difference was not significant (P=0.14). The sustained complete response, i.e., HCV RNA negativity at the end of the follow-up, as well as the maintenance of ALT normalization during the follow-up period, was more frequent in group B (38%) than in group A (18%) although the difference was not significantP=0.08). The rate of HCV reactivation after interferon was discontinued was significantly lower in group B (16%) than in group A (59%) (P<0.01). Although this combination therapy did not lead to a sufficiently sustained complete response, it could serve as adjuvant antiviral therapy when a suitable dosage and administration period are determined.  相似文献   
40.
Abstract: To compare the efficacy of low and relatively high dosages of recombinant interferon (IFN)-α-2a in Japanese patients with chronic hepatitis C, as well as to characterize the type of patients who will respond well to a low-dosage treatment, 88 patients with histologically proven chronic hepatitis C were randomly assigned to two treatment groups; one treated with IFN-α-2a 6 MU daily for 2 weeks followed by 6 MU three times weekly for 22 weeks (6-MU group), and another given the same initial treatment followed by 3 MU three times weekly for 22 weeks (3-MU group). The rate of sustained normalization of ALT 6 months after the cessation of treatment was 33% in the 3-MU group and 40% in the 6-MU group (p=0.64). In addition, there was no difference in elimination of serum HCV-RNA 6 months after the cessation of treatment between the 3-MU group (26%) and 6-MU group (29%). Multivariate stepwise regression analysis revealed that serum HCV-RNA level (p=0.0035) and platelet count (p=0.0009) were independent variables useful in predicting a sustained response of ALT. The sustained response rate of ALT in patients with a serum HCV-RNA level less than 105 copies/ml and serum platelet level above 15×104/μl was 71%, whereas that in patients with a serum HCV-RNA level above 105 copies/ml and serum platelet level less than 15×104/μl was 12%. These results indicate that a high rate of sustained response to IFN therapy can be expected in chronic hepatitis C patients with a low serum level of HCV-RNA and a high level of platelets, even if treated with a low dose of IFN.  相似文献   
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