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331.
For clinical application of adoptive immunotherapy against hepatocellular carcinoma (HCC), it is not easy to prepare tumour specific effector cells such as cytotoxic T lymphocytes (CTL). To induce potent and broad-spectrum effectors, allogeneic cultured hepatoma cell lines (JHH-4 and HuH-6) were used as stimulators of peripheral blood lymphocytes (PBL) instead of autologous HCC cells. Allogeneic tumour- and lymphokine-activated killer cells (ATLAK) were generated by a mixed culture of lymphocytes and allogeneic cultured tumour cells with recombinant interleukin-2 (rIL-2). The tumour-killing activity of ATLAK induced by HuH-6 was confirmed against HuH-6 and other different HCC cell lines (JHH-2, HuH-7 and PLC). These activated lymphocytes were significantly more potent than lymphokine-activated killer cells (LAK) in [51Cr]-releasing assay. The JHH-4 stimulated ATLAK was reactive not only with JHH-4 but also with JHH-2. The lysis of allogeneic targets could be partially inhibited by anti-CD8 and anti-CD3 but not by anti-CD4. Anti-tumour cytotoxicity in these cultures might be mediated by CD3+CD56- and CD3+CD56+ effectors. These results imply that adoptive immunotherapy for HCC with ATLAK may be more feasible than that with LAK.  相似文献   
332.
Endoscopic biliary drainage (EBD) is usually performed after endoscopic sphincterotomy (EST). In some patients, however, EBD without EST, so-called nonEST-EBD, is also effective. Thirty-four patients treated from 1983 to the present, were investigated to estimate the usefulness, safety, and drawbacks of nonEST-EBD. First, the reasons for adopting nonEST-EBD were reviewed in each patient. The most common reason was to reduce jaundice so as to preserve the function of the papilla of Vater in patients with choledocholithiasis who were to undergo surgery. However, such patients were treated in the early period of the investigation, and most would have undergone EST just after endoscopic retrograde cholangiography (ERC), had they been treated more recently. The most important reason, at present, was, thus, to avoid bleeding in patients with general or local hemorrhagic diathesis, who accounted for 20.6% (7/34 of our subjects). Next, the effect of drainage was examined. Drainage in seven patients was judged to be excellent, while that in 15 patients was determined to be effective. In 10 patients without jaundice, nonEST-EBD was performed to prevent jaundice. Therefore, in 91.7% of patients (22/24), nonEST-EBD was considered to be useful. Changes in the serum amylase level were investigated to estimate the safety of nonEST-EBD. Twenty-seven patients with nonEST-EBD, in whom the serum amylase level was within normal limits before treatment, and 57 patients with EBD after EST were evaluated. No statistically significant difference was recognized between these two groups in the degree of serum amylase elevation after drainage. NonEST-EBD is concluded to be an effective and safe method of reducing jaundice, if appropriate patients are selected.  相似文献   
333.
A gramicidin S (GS) analog ([d -Dpr4,4] GS) containing d -α,β-diaminopropionic acid (D-Dpr) in place of D-Phe at 4,4′ positions was derived from [l -Orn(δ-formyl)2,2, d -Dpr(β-Z)4,4′]GS, which was synthesized by conventional method in solution. An analog [ΔAla4,4′]GS was synthesized from [l -Orn(δ-Boc)2,2′, d -Dpr4,4′]GS through Hofmann degradation of the d -Dpr residues. Antimicrobial activities of these analogs were tested; [d -Dpr(β-Z)4,4′]GS and [ΔAla4,4′]GS showed high antimicrobial activities against Gram-positive bacteria. [d -Dpr4,4′]-GS showed an appreciable activity against Gram-negative bacteria such as Escherichia coli. Four semigramicidin S (semiGS) analogs such as [ΔAla4]semiGS were synthesized; these had no antimicrobial activity. Analogs containing ΔAla residues were hydrogenated, and the formation of l -Ala or d -Ala residues was determined. The ΔAla residues in [ΔAla4,4′] GS were reduced to dl -Ala, and ΔAla in [ΔAla4]semiGS mostly to l -Ala. The relationships of the antimicrobial activity, CD curves and asymmetric hydrogenation to the structure were discussed.  相似文献   
334.
BACKGROUND: In Japan, palivizumab was approved in 2002 for prophylaxis of severe respiratory syncytial virus disease in high-risk infants. In order to evaluate the efficacy and safety of this drug, a questionnaire survey was conducted. METHODS: A questionnaire was sent to member institutions of the Japan Neonatologist Association. The subjects were premature infants who were considered possible candidates for treatment with palivizumab. RESULTS: A total of 6302 case reports, including those of 2806 infants receiving palivizumab (group P) and 3496 infants not receiving palivizumab (group NP), respectively, were retrieved. Background characteristics revealed significant lower gestational age (GA) and birthweight for group P (P < 0.0001). Sex ratio did not differ significantly, while use of oxygen and mechanical ventilation in the neonatal intensive care unit, and presence of chronic lung disease were significantly higher for infants in group P (P < 0.0001). When comparison of hospitalization rate for respiratory symptoms was performed with stratification by eligibility criteria, in the group of infants born at 29-35 weeks GA the hospitalization rate was 4.0% and 5.7% in groups P and NP, respectively (P < 0.05). Multivariate analysis also showed that prophylaxis with palivizumab was the only variable that significantly decreased rate of hospitalization (odds ratio 0.630, P= 0.0053). The incidence of adverse events associated with the administration of palivizumab was low. CONCLUSION: In this non-randomized questionnaire survey, multivariate analysis showed that palivizumab significantly decreased the rate of hospitalization due to respiratory symptoms for infants born prematurely at 29-35 weeks GA. These data confirmed the efficacy and safety of palivizumab.  相似文献   
335.
Oridonin, a diterpenoid isolated from the plant Rabdosia rubescens, induces human epidermoid carcinoma A431 cell death through apoptosis and tyrosine kinase pathway. To examine the pathway of oridonin-induced A431 cell death, morphologic observation, lactate dehydrogenase activity-based assay, DNA agarose gel electrophoresis and Western blot analysis were carried out. When A431 cells, which overexpress epidermal growth factor receptor (EGFR), were treated with oridonin, caspase-3 was activated followed by the degradation of caspase-3 substrates, inhibitor of caspase-activated DNase (ICAD) and poly(ADP-ribose) polymerase (PARP) in a time-dependent manner. Oridonin promoted the release of cytochrome c and the down-regulation of mitochondrial transmembrane potential (ΔΨm). Oridonin up-regulated the expression ratio of mitochondrial proteins, Bax/Bcl-2. In addition, the total tyrosine kinase activity of A431 cellular proteins and the expression of EGFR were markedly reduced after oridonin treatment. Taken together, oridonin induced apoptosis in A431 cells via mitochondrial pathway, activation of caspase-3 and inhibition of tyrosine kinase activities.  相似文献   
336.
The dynamics of cytotoxic T lymphocyte precursors (CTL-p) in mice injected with allogeneic spleen cells (SC) was studied with special reference to changes in their radiation sensitivity. Whole-body 400 rad X-ray irradiation of allo-SC-primed and unprimed mice virtually abolished the capacity of their SC to proliferate and to generate CTL in primary or secondary mixed leucocyte culture (MLC). However, the impaired ability of SC to generate CTL in the primary MLC was restored by interleukin 2 (IL-2). This showed that helper cells whose activity was replaceable with IL-2 (IL-2-producing cells) were functionally more radiation-sensitive than CTL-p in unprimed mice. In contrast, the radiation-impaired activity in secondary MLC was not restored by IL-2, suggesting that memory CTL-p in allo-SC-primed mice were unexpectedly sensitive to radiation. The D37 values determined from the percentage of residual CTL-p activity of SC in bulk cultures 1 day after irradiation were 525 rad for virgin CTL-p and 75 rad for memory CTL-p. Further studies demonstrated that the radiation-sensitive memory CTL-p were generated from relatively radiation-resistant precursors, largely independent of radiation-sensitive IL-2-producing cells and of cellular proliferation. The mean frequency of CTL-p in SC measured by limiting dilution assay was not significantly increased by the priming. This supports our conclusion that the development of the memory CTL-p activity in allo-SC-primed mice did not depend on clonal expansion. Whole-body 400 rad-irradiation reduced the frequency of CTL-p in SC from unprimed mice to 1/2-1/3 and that in SC from allo-SC-primed mice to 1/8-1/15. This supports the view that the majority of radiation-resistant virgin CTL-p functionally mature to radiation-sensitive memory CTL-p without cellular proliferation in allo-SC-primed mice.  相似文献   
337.
Epicardial and and Endocardial [K+]0 Rise and KATP Channels. Introduction: KATP channels are activated predominantly in the epicardium during regional ischemia. Therefore, the role of KATP channels in ischemia-induced rise of extracellular potassium concentration ([K+]o) might he greater in the epicardium. Methods and Results: In 18 anesthetized dogs, the left anterior descending coronary artery (LAD) was ligated, followed by injection of 23-μm latex heads into the occluded artery to interrupt collateral flow, by which accumulated [K+]o might wash out. Epicardial and endocardial [K+]o were measured during a 20-minute period of ischemia using a valinomycin membrane. The dogs were divided into three groups: 6 control dogs (CTRL); 7 dogs pretreated with intravenous glibenclamide (0.3 mg/kg [GLIB]), a blocker of KATP channels: and 5 dogs pretreated with intravenous nicorandil (0.2 to 0.25 mg/kg [NCR]), a KATP channel opener. Before LAD occlusion, there was no difference in [K+]o among the three groups. In the control group, epicardial and endocardial [K+]o were increased to a similar level as a function of time after occlusion (CTRL) at both layers. Ischemia-induced epicardial [K+]o rise was suppressed by GLIB (8.4 ± 0.4 vs 6.7 ± 0.5 mM, P < 0.05) but augmented by NCR (12.9 ± 2.0 mM, P < 0.05). In contrast, endocardial [K+]o, rise remained unaffected (7.6 ± 0.2 mM CTRL, 7.6 ± 1.3 mM GLIB, and 9.4 ± 2.2 mM NCR, P = NS). Conclusion: Activation of KATP channels plays an important role in epicardial [K+]o rise, but not in endocardial [K+]o rise, during regional ischemia. Another mechanism(s) may he important for endocardial [K+]o accumulation.  相似文献   
338.
Hepatitis C virus (HCV) leads to chronic liver disease in at least 50–60% of infected people and approximately 40–50% of these patients will go on to develop cirrhosis due to chronic hepatitis C (HCV-C). The pathogenic mechanisms that result in HCV-C are unknown. Sixty Japanese patients with HCV-C were examined for HLA-A, B, C and DR alleles by serologic typing and for HLA-DQB1 alleles by DNA typing using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. As the control population, 293 healthy un-related Japanese were used. The frequencies of HLA-B61, Cw3, DR4, DQB1*0401 and DQB1*0402 were increased, while those of HLA-DR9, DQB1*0301 and DQB1*0303 were decreased in the patients. The co-ordinate increase in the frequency of HLA-DR4, DQB1*0401 or 0402 and decrease in the frequency of DR9 or DQB1*0303 were suggestive of a strong linkage disequilibrium between HLA-DR4 and DQB1*0401 or 0402 and between HLA-DR9 and DQB1*0303, respectively. From the odds ratio (OR) analysis, the combinations of HLA-Cw3+DR4-DQB1*0401 or 0402, or HLA-B61+DR4-DQB1*0401 or 0402 increased the risk for developing HCV-C when compared to each HLA allele alone. This suggested an additive effect for these classes I and II HLA allele combinations in HCV-C. In contrast, HLA-DR9-DQB1*0303 and DQB1*0301 may confer resistance to this disease. These results suggest the existence of HLA-linked susceptibility genes to HCV-C.  相似文献   
339.
This article describes the case of a 71 -year-old woman in whom a permanent pacemaker implantation was performed through an iliac vein because of superior vena cava obstruction after aortic valve reoperation. During a 6-month follow-up, the patient did well and the pacemaker performance was satisfactory.  相似文献   
340.
Two patients with Tsutsugamushi disease (fever) were successfully treated with tetracycline derivatives after typical eschars were found, although one of the patients was initially misdiagnosed as having a drug reaction eruption. Prompt diagnosis and treatment are important because this disease can be associated with considerable morbidity and simple effective treatment is easily available.  相似文献   
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