异体异位发育小鼠睾丸组织中精子功能相关基因和蛋白的表达研究

目的:采用已建立的未成熟睾丸组织移植模型,研究异体异位生长发育的小鼠睾丸组织中精子功能相关基因Asrgl1,Gpx4,Asp,Prdx4和Spa17及其相关蛋白GPX-4和PRX-Ⅳ的表达,以迸一步评估该移植模型在生殖医学中应用的可行性.方法:以1～2 d小鼠睾丸组织为供体,7～12周雄性免疫缺陷小鼠为受体进行组织移植;移植8周后收取移植物组织,采用荧光定量PCR法检测移植物中Asrgl1,Opx4,Asp,Prdx4和Spa17的表达情况,并与正常小鼠睾丸组织进行对比;同时采用Western blot检测GPX-4和PRX-Ⅳ 2种蛋白的表达情况.结果:基因检测显示,5种受试基因在移植物中的表达与8周正常小鼠睾丸组织相比均有下调;蛋白分析提示,GPX-4和PRX-Ⅳ 2种蛋白在8周正常小鼠睾丸组织中表达而在小鼠睾丸组织移植物中表达缺陷.结论:几种主要在精子运动、精子顶体形成及精子的受精功能中发挥作用的基因和蛋白在移植物中表达下调及缺失提示,异体异位睾丸组织移植在临床应用的可行性还需进一步评估     

睾丸组织异体异位移植研究进展

自从2002年《自然》杂志发表了第1篇用同种或异种睾丸组织移植进行的生精细胞体外发育研究以来,该技术被广泛应用于不同种类动物(包括人类)睾丸组织的体外成熟的探讨。这种采用免疫缺陷动物作为受体,同种或异种睾丸组织为供体的技术与其他生精细胞体外成熟方法相比具有环境条件较易控制、重复性较好等优点。迄今为止,在用小鼠、仓鼠、猫、兔、猪、山羊、牛和恒河猴等动物睾丸组织进行的移植研究中,未成熟生精细胞在作为受体的裸鼠体内均发育到精子阶段,并通过卵细胞胞质内单精子注射(ICSI)技术,用发育成的小鼠、兔精子分别产生了下一代。本文总结了供体组织的种类和年龄,受体的性别、完整性、免疫状况和移植部位以及移植时间对移植物发育的影响,概述了近几年来采用该技术所进行的睾丸组织移植研究发展现状,并对该技术的应用以及存在的问题进行了讨论。     

睾丸移植物中支持细胞相关基因和蛋白表达的研究

目的 研究新生小鼠睾丸组织异体异位移植后,几种在睾丸支持细胞中起重要作用的基因和蛋白表达情况,为异体异位睾丸组织移植模型用于科研及临床的可行性提供进一步实验数据.方法 将162只1～2d昆明小鼠的睾丸移植到54只7～12周去势雄性免疫缺陷小鼠背部;在移植后9个时间段(3d和1～8周)取出移植物;选取4种在睾丸支持细胞中表达或高表达的基因abp、amh、vim和clu,采用聚合酶链反应,对发育不同阶段移植物中4种基因的表达情况进行分析,并与正常小鼠相应各年龄段睾丸中的基因表达相比较;同时采用免疫组织化学方法对支持细胞的GATA-4蛋白在移植物组织中的表达量及分布情况进行分析.结果 在9个时间段取出的移植物中,所测定4种基因的表达趋势与在正常小鼠睾丸中所见基本相同;免疫组化结果显示,4周和8周移植物支持细胞中GATA-4蛋白呈高表达,与在正常小鼠睾丸组织支持细胞中的表达基本一致.结论 新生小鼠睾丸组织异体异位移植到免疫缺陷小鼠体内后,支持细胞的发育在组织形态学以及几种受试基因的表达趋势和蛋白的表达情况与在正常小鼠中的表现基本相同.     

DNA损伤修复基因多态性与食管癌的研究进展

DNA损伤修复基因在DNA损伤修复、防止细胞突变中起重要作用。DNA损伤修复基因多态性与肿瘤的关系是近来研究的热点。本文就DNA损伤修复基因多态性与食管癌的关系进行综述。     

DNA损伤修复基因多态性与食管癌的研究进展

DNA损伤修复基因在DNA损伤修复、防止细胞突变中起重要作用。DNA损伤修复基因多态性与肿瘤的关系是近来研究的热点。本文就DNA损伤修复基因多态性与食管癌的关系进行综述。     

DNA损伤修复基因多态性与男性不育的研究进展

DNA修复机制的缺陷能引起生殖细胞DNA损伤的增加,从而导致精子产生过程出现异常和男性不育.高保真DNA修复对维持生殖细胞基因组的完整性和质量至关重要.因此,正常的精子生成过程中DNA损伤修复系统是一个关键因素,参与生殖细胞DNA损伤修复基因功能的异常会造成精子数量减少以及精子异常.本文主要从DNA损伤修复基因XRCC...     

可卡因诱导大鼠睾丸细胞凋亡的研究

目的：探讨长期使用可卡因导致睾丸损害中细胞凋亡的作用。方法：实验组每天给25d龄雄性Wistar大鼠皮下注射盐酸可卡因（15mg/kg),共80d。对照组每天给相同剂量的普通生理盐水,共80d。在可卡因使用的第20、40、80d分别处死动物并取睾丸,用TUNEL、流式细胞技术检测睾丸细胞凋亡的情况。结果：细胞凋亡在使用可卡因20d出现,40d达高峰,且持续80天才开始下降,同对照组相比差异有显著性意义（P＜0.05)。流式细胞分析出现凋亡峰。结论：使用可卡因可以导致大鼠睾丸细胞显著凋亡,导致睾丸损害的机制可能与细胞凋亡有关。     

睾丸移植物间质细胞4种基因的表达分析

目的 研究新生小鼠睾丸组织异体异位移植后,4种在睾丸间质细胞中起重要作用的基因表达情况,为异体异位睾丸组织移植模型用于科研及临床的可行性提供进一步实验数据.方法 将162只1～2d昆明小鼠的睾丸移植到54只7～12w去势雄性免疫缺陷小鼠背部;在移植后9个时间段(3d和1～8w)取出移植物;选取4种在睾丸间质细胞中表达或高表达的基因3β -hsd、1hr、p450scc和star,采用聚合酶链反应,对发育不同阶段移植物中4种基因的表达情况进行分析,并与正常小鼠相应各年龄段睾丸中的基因表达情况相比较.结果 在9个时间段取出的移植物中,所测定4种基因的表达趋势与在正常小鼠睾丸中所见基本相同.结论 新生小鼠睾丸组织异体异位移植到免疫缺陷小鼠体内后,间质细胞4种受试基因的表达趋势与在正常小鼠中的表现基本相同.     

胰腺癌组织中细胞凋亡及相关基因bcl-2和bax表达的研究

为了探讨细胞凋亡及相关基因ｂａｘ和ｂｃｌ 2表达在胰腺癌形成和发展中的作用 ,我们对 31例胰腺癌和 14例慢性胰腺炎组织中细胞凋亡情况及ｂａｘ和ｂｃｌ 2基因表达产物进行检测 ,现报告如下。资料与方法1.一般资料 :收集 1990年 1月至 1998年 7月手术切除的胰腺癌标本 31例 ,其中男 2 1例 ,女 10例 ,平均年龄 5 4岁。其中高分化腺癌 15例 ,中度分化腺癌 6例 ,低分化腺癌 9例 ,未分化腺癌 1例。按ＴＮＭ进行临床分期 ,Ⅰ期 5例 ,Ⅱ期6例 ,Ⅲ期 11例 ,Ⅳ期 9例。选取同期 14例慢性胰腺炎标本作对照研究。2 .染色方法 :检测细胞凋亡采用ＩＳ…     

Effects of strontium fructose 1,6-diphosphate on expression of apoptosis-related genes and oxidative stress in testes of diabetic rats

Objective:   To investigate the effects of strontium fructose 1,6-diphosphate (FDP-Sr) on testicular dysfunction induced by diabetes.
Methods:   Diabetes was induced by a single injection of streptozotocin (65 mg/kg, i.p.). After 28 days, therapy with three doses (50, 100, and 200 mg/kg per day, p.o.) of FDP-Sr was carried out for another 4 weeks.
Results:   The rats exhibited morphological lesions of testes and significant decreases in serum testosterone levels after 2 months of diabetes. Testicular tissues of diabetic rats showed significantly increased malondialdehyde levels and declined glutathione peroxidase activity. Meanwhile, augmented DNA fragmentation was observed, along with downregulated Bcl-2 and upregulated Bax expressions at both mRNA and protein levels. FDP-Sr showed significant antioxidant effects in both in vitro and in vivo experiments, and significantly relieved apoptosis and the decline of serum testosterone caused by diabetes.
Conclusions:   Testicular injury and apoptosis induced by diabetes are partially attributed to the augmented oxidative stress in testicular tissue. FDP-Sr indirectly alleviates these pathologic alterations by suppressing the generation of reactive oxygen species.     

小鼠睾丸移植物中3种生精阶段特异性基因的表达

目的 采用逆转录-聚合酶链反应，探讨新生小鼠睾丸组织移植到裸鼠体内后，3种阶段特异性基因，缺失型无精子基因（Daz1）、磷酸甘油激酶2（Pgk2）和鱼精蛋白-2（Prm2）在不同发育阶段移植物中的表达情况。方法 将180只出生1-2d昆明小鼠睾丸移植到60只7-12周去势雄性免疫缺陷小鼠背部；在移植后不同时间段（分为3d、1周-8周和12周10个组）取出移植物，对在发育不同阶段表达的3种基因出现的时间及表达情况进行分析测定，并与相应各年龄段正常小鼠睾丸中的基因表达相比较。同时进行组织形态学观察，对比各种基因出现的时间与小鼠睾丸发育周期的吻合性。结果 在10个时间段取出的移植物中，所测定的3种基因表达趋势与在正常昆明小鼠睾丸中所见基本相同，并与小鼠发育周期基本吻合。结论 新生小鼠睾丸组织移植到免疫缺陷小鼠体内后，生精细胞的发育在形态学和几种受试基因出现的时间上与在正常小鼠中表现均相似。从而对该睾丸组织移植模型用于生精细胞异体异位生长发育研究及基因调控机制研究的可行性提供了进一步的理论依据。     

Downregulation of apoptosis-related genes in keloid tissues

BACKGROUND: The induction of immunological tolerance by orthotopic liver transplantation (OLT) is donor-specific. Moreover, after the acceptance of a liver, other organs are not rejected. The aim of this study is to clarify characteristics of the prolonged islet survival as a result of immunological tolerance which was induced following simultaneous OLT. MATERIALS AND METHODS: About 2000 islets were isolated from F344 rats. OLT was performed from F344 rats to diabetic LEW rats. Then the islets were transplanted into the transplanted F344 livers of diabetic LEW rats. Survival of the pancreatic islet allografts and deposits of IgM and IgG in the transplanted liver and islets were investigated. RESULTS: Survival time in the group with OLT (mean survival time: 46.4 +/- 38.2 days) was significantly longer than that without OLT (mean survival time: 8.1 +/- 0.8 days) (P < 0.01). Amount of serum antibody against donor lymphocytes was slightly higher in the group without OLT, and was very high in the group with OLT. Histologically, severe lymphocytic infiltration was observed in the Glisson's sheaths in the group with OLT. Islets were lodged, without lymphocytes inside, in small branches of the portal vein 7 days after transplantation. Immunohistologically, IgM and IgG deposits were found in the Glisson's sheaths and along sinusoids; however, they were not found in the islets. CONCLUSIONS: Induction of immunological tolerance and long-term survival of islets are possible by simultaneous OLT. The mechanism of this tolerance could be the host's selection of the liver as a target of preferred immunological attack.     

增生性瘢痕中凋亡相关基因转录的变化

目的　探讨凋亡相关基因bcl -2、bax、p5 3和c- myc在不同形成时期的增生性瘢痕中的基因转录变化。方法　提取 16例不同发生时期的增生性瘢痕和 8例正常皮肤的总RNA后 ,分离mRNA ,用逆转录 聚合酶链反应 (RT PCR)方法检测bcl- 2、bax、p5 3和c -myc基因在不同组织中的表达。结果　在增殖期的瘢痕中 ,凋亡促进基因bax、c- myc和 p5 3的表达量分别是正常皮肤的(62 .8± 14 .7) %、(78.0± 17.0 ) %和 (4 9.8± 4.3 ) % ,基因表达明显降低 (P <0 .0 5 ) ,而在成熟期的瘢痕中 ,这 3种基因的表达量都明显高于增殖期的瘢痕 ,恢复到正常皮肤水平。在正常皮肤中 ,bcl- 2基因表达水平较低 ,而在增殖期和成熟期的增生性瘢痕中表达量都显著升高 (P <0 .0 5 )。结论　bax、c- myc和 p5 3基因表达降低 ,bcl- 2基因表达增强可能是瘢痕中细胞凋亡减少 ,形成增生性瘢痕的机制之一 ,而bax、c- myc和 p5 3基因表达增强可能与瘢痕达到成熟状态有关。     

Surveillance on mutation carriers of DNA mismatch repair genes

Hereditary nonpolyposis colorectal cancer (HNPCC) is an autosomal dominant inherited cancer susceptibility syndrome signifying a very high risk of colorectal and endometrial cancer at young age. It also entails an increased risk of a variety of other tumours, such as ovarian, gastric, uroepithelial and biliary tract cancer. The underlying pathogenic mutation lies in one of the five known DNA mismatch repair genes (MSH2, MLH1, PMS1, PMS2, and MSH2). The majority of HNPCC patients and families can at present be identified and the underlying mutation detected by genetic diagnostics. This provides the opportunity for predictive genetic testing to exclude or identify the mutation carrier status of the family members at risk. Mutation-negative individuals can then be relieved from any extra cancer threat. For mutation-positive individuals a preventive surveillance programme offers substantial benefits in reducing the cancer incidence, almost precluding death of colorectal cancer and reducing overall mortality.     

Expression of apoptosis-related genes and proteins in experimental chronic renal scarring

Apoptosis has been proposed to play an important role in the progression of renal scarring. The mechanisms that determine whether a cell enters the apoptotic program are complex. Bax and Bcl-2 are recognized modulators of this event; their relative levels determine the fate of cells. A role for apoptosis in the progression of renal scarring in the remnant kidneys of rats submitted to subtotal nephrectomy (SNx) has been described. This study investigated the expression (protein and mRNA) of Bax and Bcl-2 in remnant kidneys between day 7 and day 120 post-SNx. Northern blot analysis showed that bax mRNA was increased in remnant kidneys from day 7 (150% of control; P: < 0.05), whereas bcl-2 mRNA was decreased from day 15 (23% of control; P: < 0.05) resulting in a 14-fold increase in the ratio of bax to bcl-2 mRNA by day 120. Western blot analysis showed similar changes in Bax and Bcl-2 protein in remnant kidneys, resulting in a 147-fold increase in the ratio of Bax to Bcl-2 on day 120. Immunohistochemistry showed increases in Bax to be located predominantly in tubules in SNx kidneys. Interestingly, Bcl-2 immunostaining increased in some epithelial cells within atrophic tubules despite the overall decrease in Bcl-2 protein and mRNA. The overall renal apoptotic cells correlated closely with the ratio of bax to bcl-2 at both the mRNA and protein levels (r = 0.594 and 0.308, respectively; P: < 0.05). Furthermore, tubular apoptosis correlated positively with the mRNA level of bax (r = 0.471; P: < 0.01) and negatively with the mRNA and protein levels of bcl-2 (r = -0.443 and -0.607, respectively; P: < 0.01). The increase in the ratio of the death inducer (Bax) to the death repressor (Bcl-2) at the mRNA and protein levels may control the apoptosis associated with the progression of tubular atrophy and chronic renal fibrosis within remnant rat kidneys. These observations may have prognostic and therapeutic implications in chronic renal failure.