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131.
132.
Since virus-specific cytotoxic T lymphocytes (CTLs) play a critical role in preventing the spread of hepatitis C virus (HCV), an effective HCV vaccine should be capable of eliciting HCV-specific CTLs. In the present study, we assessed the capability of a novel recombinant vaccine using an attenuated tuberculosis bacillus, Calmette-Guerin bacillus (BCG), as a vaccine vehicle to elicit HCV-specific CTLs. BCG was engineered to express the CTL epitope of HCV-non-structure protein 5a (NS5a) as a chimeric protein with alpha antigen of mycobacteria. Immunization with this recombinant BCG elicited major histocompatibility complex class I-restricted CD8(+) HCV-NS5a-specific CTLs in mice. Immunized mice showed a substantial reduction in the vaccinia virus titer compared with control mice when the immunized mice were challenged with a recombinant vaccinia virus expressing HCV-NS5a genes. These findings provide evidences for the possibility of BCG as a vaccine vector and its continued exploration as a vehicle for eliciting HCV-specific immunity.  相似文献   
133.
1. The aim of the present study was to establish a new schedule of active avoidance response in rats to estimate the central effects of second-generation histamine H1 receptor antagonists. 2. With the new schedule, a rat was placed into a dark room. A sliding door was opened after a delay of 5 s and, unless the animal moved into the lit room, an electric shock was delivered for 3 s. With the conventional schedule, the sliding door was opened immediately after the rat was placed into the dark room. 3. Ketotifen, at a dose of 50 mg/kg, showed no significant effect on the retrieval of active avoidance response with the conventional schedule. However, with the new schedule, the drug caused significant inhibition of retrieval of the response, even at a dose of 10 mg/kg. 4. Epinastine showed no significant effect on retrieval of the active avoidance response, even at a dose of 50 mg/kg with the new schedule. 5. Cetirizine, at a dose of 50 mg/kg, caused a significant effect, indicating that cetirizine, at this dose, markedly inhibits memory retrieval. 6. Both olopatadine and loratadine had potent effects; at doses of 20 and 50 mg/kg, respectively, these agents showed significant inhibitory effects on retrieval of the response. 7. In conclusion, we have developed a new schedule of active avoidance response that can be used to estimate the central effects of second-generation histamine H1 receptor antagonists.  相似文献   
134.
We treated a patient with gastric cancer considered to be unresectable due to peritoneal metastasis, who responded remarkably to treatment with TS-1. The patient was a 62-year-old male. His diagnosis was gastric cancer, for which he underwent surgery on February 22, 2001. Laparotomy disclosed many nodules measuring 2-3 mm in diameter in the abdominal cavity, so rapid pathological tests were conducted during the operation. The test results indicated peritoneal metastasis from gastric cancer. Therefore, simple laparotomy was employed as the best option. On day 13 after surgery, oral administration of TS-1, bid., at a daily dose of 120 mg was commenced. In our outpatient clinic, he was given 3 courses, each comprising 4 weeks' medication and 2 weeks' discontinuation. Subsequently, upper digestive tract endoscopy was performed but only scars in the gastric vestibular area were observed. Biopsy could not detect any malignant findings. Medication was discontinued due to the patient's preference and he died of gastric cancer 10 months after operation.  相似文献   
135.
We treated five cases for multiple hepatic metastases from gastric cancer with a novel combination of TS-1 and low-dose cisplatinum (CDDP). TS-1 was orally administered at 100 mg/body/day every day or only on weekdays, and 10 mg of CDDP was infused once or twice a week. The efficacy was evaluated by body CT after the treatment. The CT showed more than a 60% reduction of hepatic tumors in four patients. The tumor markers, CEA and CA19-9, were reduced to 10%. The response rate was 80%. Adverse reactions of grade 1 anemia were observed in two patients and grade 1 leucopenia in one patient. The liver function normalized in one patient. The hemoglobin level was increased from 6.8 g/dl to 11.8 g/dl in one patient. In conclusion, this combined chemotherapy of TS-1 and low-dose CDDP proved useful for advanced gastric cancer patients with multiple hepatic metastases, in view of its therapeutic efficacy, patients' quality of life and low toxicity.  相似文献   
136.
Interferon-gamma (IFNgamma) has been shown to induce apoptosis through the induction of the Fas antigen in certain cell lines. In this study, we used four melanoma cell lines (MMN9, PMP, MAA and HMG) to study the antiproliferative effect of exogenous IFNgamma treatment, the expression of IFNgamma-induced Fas antigen, and the combined effect of IFNgamma and anti-Fas antibody (CH-11). We also investigated the relationship between Fas-mediated apoptosis and the expression of the bcl-2 family, measured using Western blotting. IFNgamma increased the mean fluorescence intensity of Fas in MMN9 and PMP cells as measured by flow cytometry. Combined therapy had a significant antiproliferative effect on MMN9 and PMP cells, as measured by the MTT assay. After exposure to IFNgamma and anti-Fas antibody, cleavage of bcl-2 occurred in apoptotic cells, and the signal intensity of both bcl-2 and bak decreased in surviving MMN9 cells, as shown by Western blotting analysis. Our results indicate that IFNgamma induces overexpression of Fas and consequently enhances the sensitivity of melanoma cells to Fas-mediated apoptosis. Furthermore, it is possible that cleavage of bcl-2 correlates with the induction of apoptosis induced by IFNgamma and anti-Fas antibody in melanoma cells. We conclude that combined therapy with IFNgamma and anti-Fas antibody may provide an alternative and more efficient chemotherapeutic approach against melanoma cells by inducing the overexpression of Fas after exposure to IFNgamma.  相似文献   
137.
We attempted to elucidate the antitussive principles of Glycyrrhizae radix, a main component of Bakumondo-to (Mai-men-dong-tang). Although the 50% methanol-eluted fraction (100 mg/kg, p.o.) caused a more than 60% reduction in the number of capsaicin-induced coughs, neither the water-eluted nor 100% ethanol-eluted fractions of water extract of G. radix had antitussive effects. The water extract of G. radix contained high levels of liquiritin, liquiritin apioside, isoliquiritin, isoliquiritin apioside and glycyrrhizin. On the other hand, the 50% methanol-eluted fraction contained mainly liquiritin and liquiritin apioside, but not the other compounds. Liquiritin apioside (3-30 mg/kg, p.o.), but not liquiritin, isoliquiritin, isoliquiritin apioside or glycyrrhizin, dose-dependently inhibited the number of coughs. Methysergide, a serotonin receptor antagonist, antagonized the antitussive effect of liquiritin apioside. However, the antitussive effect of liquiritin apioside was not antagonized by naloxone. Pretreatment with glibenclamide (3 mg/kg, i.p.), an ATP-sensitive potassium channel blocker, also significantly reduced the antinociceptive effect of liquiritin apioside. These results suggest that G. radix contains a potent antitussive compound, liquilitin apioside, whose antitussive effect may depend on both peripheral and central mechanisms.  相似文献   
138.
A novel hydrophilic gold compound, tetrakis((trishydroxymethyl)phosphine)gold(I) chloride 1, has been investigated for its antitumor properties. In vitro studies demonstrate that 1 is active against HCT-15, AGS, PC-3, and LNCaP tumor cells. Cell cycle analysis of the HCT-15 cells by flow cytometry revealed elongation of the G1 phase of the cell cycle leading to growth inhibition. Administration of 1 to Balb/C mice inoculated with syngenic meth/A cells demonstrated statistically significant dose-dependent survival time.  相似文献   
139.
The utilization of generic drugs has been promoted, but there is concern about the insufficiency of the information provided on generic drugs. To make an objective evaluation of the amount of information supplied by generic drug manufactures, we tried to quantify the information supply. The information described in the package insert and the interview form were used in the evaluation. We sent a questionnaire to 1000 randomly selected hospitals nationwide to determine the necessity of each information item in medical practice, and weighted the score allotted to each item based on replies from 524 hospitals. We applied these procedures to diclofenac sodium products and found that the score for a branded drug was 60.5 points and that for generic drugs ranged from 1.6 to 58.3 points. This indicates that there were great variations in information supply activities among the manufacturers. The Qua value, which was the ratio of the points of a generic drug per unit price in the drug tariff to the points of the branded drug, ranged from 0.1 to 2.4. We think that these procedures will make it possible to select the appropriate generic drugs in medical practice.  相似文献   
140.
The effects of [Arg(8)]-vasopressin (AVP) and related compounds on regional cerebral blood flow (rCBF) in the hippocampus were studied using conscious spontaneously hypertensive rats (SHR). rCBF in the hippocampus decreased gradually with age in proportion to an increase in mean blood pressure. Subcutaneous injection of AVP caused a dose-dependent increase in rCBF in the hippocampus. The effects of the metabolic fragments AVP4-9 and AVP4-8 on rCBF were relatively weak. OPC-31260, a vasopressin V(2) antagonist, antagonized the AVP-induced increase in rCBF in the hippocampus. Furthermore, subcutaneous injection of DDAVP, a V(2) agonist, increased rCBF in the hippocampus. On the other hand, the AVP-induced increase in rCBF in the hippocampus was not antagonized by OPC-21268, a vasopressin V(1) antagonist. Intracerebroventricular injection of AVP caused no significant changes in rCBF in the hippocampus, even at a dose of 10 ng/site.  相似文献   
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