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31.
BACKGROUND: The responses of mice to the mite allergen Der p 1 have been used to study the mechanisms of allergic sensitization and the development of new types of immunotherapy. Many of the studies require a knowledge of the T cell epitopes, and because Der p 1 is polymorphic, the effect of natural amino acid substitution in the allergen. The intranasal administration of peptides containing T cell epitopes can induce a mucosal tolerance but it is not known if the major activity is limited to stimulatory peptides and if, as found for autoimmunity, some epitopes are not inhibitory. OBJECTIVE: To determine and compare the sequences of Der p 1 which contain stimulatory epitopes for the high responding H-2(b) and H-2(q) mice and the sequences which induce tolerance by intranasal administration of peptides. METHODS: T cell responses of mice immunized with Der p 1 were measured by in vitro T cell stimulation assays so an extensive study of epitope recognition and intranasal tolerance could be made. Synthetic peptides were used to examine the stimulatory and inhibitory ability of all Der p 1 sequences and to map the major H-2(b) epitope in detail. This included the effect of the common polymorphic amino acid 124 substitution found within this epitope. RESULTS: Three and two regions, respectively, were found to contain stimulatory T cell epitopes for H-2(b) and H-2(q) mice. The peptides in these regions were also the most active at inducing intranasal tolerance for the responding haplotype. The correspondence between inhibitory and stimulatory peptides was maintained for the fine mapping of the major H-2(b) epitope. This was found about a core region of 118-126 which was overlapping but separate to a consensus sequence for the binding of endogeneous peptides. Peptides with alanine at the naturally polymorphic residue 124 stimulated and inhibited responses to Der p 1 more effectively, while peptides with the valine 124 variant were immunogenic but poorly cross-reactive. CONCLUSIONS: The intranasal administration of peptides representing each of five epitopes recognized by two strains of mice were able to induce mucosal tolerance and the major tolerizing activity was limited to these epitopes. The position of the core major epitope for C57 mice, which differs from a previously predicted epitope, and its specificity for the natural alanine 124 variant is described. 相似文献
32.
胃癌和胃癌前病变Cx43、PCNA的表达及意义 总被引:3,自引:1,他引:2
目的 通过观察间隙连接蛋白 Cx4 3和增殖细胞核抗原 (PCNA )在正常胃粘膜、胃癌前病变和胃癌中的表达和分布情况 ,探讨 Cx基因表达与胃癌发生的关系。 方法 运用 SP免疫组织化学方法检测 Cx4 3、PCNA在 70例原发性胃癌 ,6 2例中、重度不典型增生和 16例正常胃粘膜中表达规律。 结果 Cx4 3在正常胃粘膜 ,中、重度不典型增生和胃癌中表达的阳性率分别为 10 0 % ,83.9%和 17.1% ,三者比较差异有显著性 (P<0 .0 5 )。 Cx4 3表达与胃癌的分化程度相关 (P<0 .0 1)。胃癌前病变、胃癌组中的 PCNA较正常胃粘膜组增高 (P<0 .0 1)。 Cx4 3表达与 PCNA呈负相关 (P<0 .0 1)。 结论 Cx4 3表达降低在胃癌发生发展中起重要作用 ,Cx4 3可做为胃癌早期诊断的指标 相似文献
33.
34.
目的 :探讨激素替代治疗对绝经后Ⅱ型糖尿病和高血压患者肾脏微血管病变的影响。方法 :36例患有Ⅱ型糖尿病和高血压的绝经后妇女随机分为治疗组和安慰剂组各 18例 ,采用双盲法予口服克龄蒙或安慰剂 1片 /日 ,共 4 5个周期 ,测量用药前后各参数值并进行比较及线性相关分析。结果 :治疗组用药前后 2 4小时尿蛋白定量由 ( 0 4 45± 0 0 36 )g降到 ( 0 36 1± 0 0 32 ) g(P <0 0 1) ,内生肌酐清除率由 ( 92 0± 5 2 )ml/min增到 ( 99 1± 4 8)ml/min (P <0 0 5) ,空腹血糖由 ( 7 0 2± 0 4 3)mmol/L降到 ( 6 55± 0 31)mmol/L(P <0 0 5) ,血清总胆固醇由 ( 6 6 6±0 2 8)mmol/L降到 ( 5 71± 0 71)mmol/L(P <0 0 1) ,血压无明显改变。 2 4小时尿蛋白定量和内生肌酐清除率与其他参数间无显著相关性。安慰剂组用药前后各项指标无明显改变。结论 :激素替代治疗对绝经后Ⅱ型糖尿病和高血压患者肾脏微血管病变有改善作用 相似文献
35.
目的 评价总前列腺特异性抗原 (tPSA)、游离前列腺特异性抗原 (fPSA)及百分率 (f/tPSA % )检测前列腺癌 (PCa)的相关性及临床价值。方法 用酶免法测定 35例PCa及 73例良性前列腺增生 (BPH)患者血清tPSA水平 ,4tPSA <10ng/ml患者另测其fPSA ,计算f/tPSA(% )。 结果 血清tPSA <4、4~ 10、>10ng/ml者发现PCa的比例组间相比均有统计学意义。 4~ 10ng/ml组 ,PCa和BPH者f/tPSA(% )分别是 9.1± 4.8、16 .4± 6 .1,差别有显著意义 (P <0 .0 1)。结论 tPSA仍是PCa筛查的有效瘤标 ,tPSA低水平时 ,f/tPSA(% )检测PCa则更为灵敏精确。 相似文献
36.
胃癌组织p16基因蛋白表达的意义 总被引:9,自引:4,他引:5
目的 检测 p1 6基因蛋白在胃癌组织、癌旁组织中的表达及其分布特点 ,分析其与胃癌临床病理学特征及预后的关系 .方法 采用 S- P免疫组织化学法对 53例胃癌组织及 35例癌旁组织进行 p1 6蛋白的定位观察 .结果 各病理类型胃癌组织、癌旁组织均有 p1 6基因蛋白表达 .阳性率分别为 62 .3% (33/53)和 88.6% (31 /35) ,阳性细胞的棕黄色颗粒主要位于细胞核 .胃癌 p1 6基因蛋白表达与性别、年龄、肿瘤部位在统计学上无差异 (P>0 .0 5) ;而与组织学类型、病理分级、淋巴结转移、临床病理分期在统计学上有差异 (P<0 .0 5) .p1 6蛋白阳性者 5年生存率 51 .0 %高于 p1 6蛋白阴性者 2 0 .0 % (P<0 .0 5) .结论 p1 6基因缺失和表达水平的改变与胃癌发生、发展密切相关 ,检测 p1 6基因蛋白表达可作为辅助临床判断胃癌的生物学行为及推测预后的指标 相似文献
37.
Objective To test the hypothesis that p53 gene therapy combined with endostatin can enhance tumor response to radiation therapy of RM-1 mouse xenograft prostate cancer and to investigate its mechanism. Methods A mouse prostate cancer model was established. Then mice with xenograft tumor were randomly divided into group A (control), B (radiation), C (radiation and rAdp53), D (radiation and rh-endostatin) and E (radiation and rAdp53 and rh-endostatin). On day 1, rAdp53 was injected intra-tumorously with 1 × 1010 vp per animal to group C and E. From day 1 to 14, rh-endostatin was given 15 mg/kg intraperitoneally daily to group D and E. On day 4 single fraction of 15 Gy was given to tumors in groups B, C, D and E. Normal saline was injected intra-tumorously or intraperitoneaUy accordingly as control. No treatment was done to group A. Tumor volume was measured daily. Samples were collected on Days 5, 10 and 15. Ki67, CD31, p53 and VEGF were detected by means of immunohistochemistry. Results (1) Radiation alone, radiation combined with intra-tumorous injection of Adp53 and/or intraperitoneal injection of rh-endostatin resulted in tumor growth arrest of RM-1 cells in vivo (P = 0.000). Radiation combined with both rAdp53 and rh-endostatin was the most effective treatment (P < 0.05). (2) All the four treatment groups had a decreased expression of mutant type P53 (P = 0.000). The expression of Ki67 in groups B and C were equal (P 0.05) and increasing (P = 0.000), respectively. Group D had a up-down-up curve (P < 0.05), but group E had a up-down one. On day 5 the expresion of VEGF in group E was the lowest (P < 0.05). An increased expression of MVD compared with the control was shown, and MVD in groups C, D and E were always higher than that in the control (P < 0.05). Conclusions The limitation of radiotherapy could be overcome by combination with beth p53 gene therapy and endostatin on the growth of mouse prostate cancer cell. Radiation, rAdp53 and endostatin have their own role but they can be interacted with each other. 相似文献
38.
39.
We performed an open, double-blind, and long-term study of vigabatrin (gamma-vinyl-GABA, GVG) in patients with treatment-resistant epilepsy who were receiving only one or at most two standard antiepileptic drugs (AEDs). The novel design included a parallel, double-blind, placebo-controlled phase that minimized the number of patients receiving placebo and allowed determination of the optimum dose of GVG for each patient before initiation of the double-blind phase. The study was divided into four phases. The first phase was a 6-week period of baseline observation. In the second phase, GVG was added openly to previous AEDs for 8 weeks. During the first 2 weeks of this phase, the dose of GVG was increased weekly and then, in the absence of adverse effects, was held constant for the next 6 weeks. At the end of this open phase, seizure frequency during the 6 weeks of constant treatment was compared with the baseline seizure frequency for each patient. Patients who experienced reduction greater than 50% in the frequency of any seizure type during the open phase were defined as responders. These responders were then entered into the third and double-blind phase, in which they were randomly allocated wither to continue active GVG treatment or placebo for 8 weeks. Thirty-three patients entered the study; 31 of 33 patients completed the initial open phase. Twenty patients achieved a reduction greater than or equal to 50% in the frequency of one or more seizure types and were eligible for the double-blind phase; 10 were randomized to continue GVG and 10 were randomized to placebo.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
40.
Five years experience of transrectal high-intensity focused ultrasound using the Sonablate device in the treatment of localized prostate cancer 总被引:3,自引:0,他引:3
TOYOAKI UCHIDA HIROSHI OHKUSA HIDEYUKI YAMASHITA SUNAO SHOJI YOSHIHIRO NAGATA TORU HYODO TAKEFUMI SATOH 《International journal of urology》2006,13(3):228-233
BACKGROUND: High-intensity focused ultrasound (HIFU) is a minimally invasive technique used in achieve coagulation necrosis. We evaluated biochemical disease-free survival rates, predictors of clinical outcome and morbidity in patients with localized prostate cancer treated with HIFU. METHODS: A total of 181 consecutive patients underwent HIFU with the use of Sonablate (Focus Surgery, Indianapolis, IN, USA). Biochemical recurrence was defined according to the criteria recommended by the American Society for Therapeutic Radiology and Oncology Consensus Panel. The median age and pretreatment prostate-specific antigen (PSA) level were 70 years (range 44-88) and 9.76 ng/mL (range 3.39-89.60). A total of 95 patients (52%) were treated with neoadjuvant hormones. The median follow-up period for all patients was 18.0 months (range 4-68). RESULTS: The biochemical disease-free survival rates at 1, 3 and 5 years in all patients were 84%, 80% and 78%, respectively. The biochemical disease-free survival rates at 3 years for patients with pretreatment PSA less than 10 ng/mL, 10.01-20.0 ng/mL and more than 20.0 ng/mL were 94%, 75% and 35%, respectively (P<0.0001). Multivariate analysis identified pretreatment PSA (P<0.0001) as a independent predictor of relapse. CONCLUSION: High-intensity focused ultrasound therapy appears to be a safe and efficacious minimally invasive therapy for patients with localized prostate cancer, especially those with a pretreatment PSA level less than 20 ng/mL. 相似文献