表达人JNK基因重组腺病毒的构建和鉴定

目的 制备表达人c-jun氨基末端激酶(JNK)复制缺陷型重组腺病毒.方法 将重组穿梭载体pAdTrack-CMV-WT-JNK线性化后,与pAdEasy-1共转化大肠杆菌BJ5138,进行同源重组得到重组腺病毒载体.将重组腺病毒载体转染入包装细胞HEK293内制备复制缺陷型重组腺病毒,并经PCR及DNA测序鉴定.结果 JNK重组腺病毒载体能有效转染HEK293细胞并在细胞内成功包装,5 d后可以观察到绿色荧光蛋白(GFP)明显表达,搜集的病毒经过PCR扩增得到特定JNK基因片段并测序鉴定.动物实验证实构建的Ad-WT-JNK能有效在肝组织表达.结论 该研究成功构建了JNK重组腺病毒载体及相应重组腺病毒颗粒,为进一步研究JNK的作用及应用JNK进行相关疾病的基因治疗奠定了基础.     

维生素D受体基因多态性与汉族、维吾尔族和哈萨克族儿童铅中毒遗传易感性

目的探讨汉族、维吾尔族和哈萨克族儿童VDR-BsmI基因多态性位点及其铅中毒遗传易感性的关系。方法PCR-RFLP方法对新疆乌鲁木齐市的汉族469名、维吾尔族443名和哈萨克族516名儿童VDR-BsmI基因多态性进行分析。分析探讨汉族、维吾尔族和哈萨克族儿童VDR-BsmI基因多态性与血铅水平的关系。结果在汉族人群中,BsmI B和BsmI b等位基因频率分别为6%和94%;在维吾尔族人群中,BsmI B和BsmI b等位基因频率分别为18%和82%;在哈萨克族人群中,BsmI B和BsmI b等位基因频率分别为43%和57%,三者差异有统计学意义(P<0.01)。维吾尔族和汉族儿童BsmI位点基因多态性与血铅水平间有相关关系。结论VDR-BsmI位点基因多态性对铅毒性影响的方式可能与机体铅的负荷量密切相关。     

乙型病毒性肝炎后肝硬化遗传易感性的研究进展

肝硬化是一种常见的慢性肝病，乙型肝炎病毒（hepatitis B virus，HBV）是引起肝硬化的主要原因之一。全球大约有3．5亿HBV携带者，而中国HBV携带者约占全球的1／3，其中约有20％～30％发展成肝硬化。且2％～5％的肝硬化患者会发展成肝癌。这对人们的生命构成了严重的威胁。因此，阐明乙型病毒性肝炎（简称乙肝）后肝硬化的发病机制，对控制盱硬化和肝癌的发生和发展具有重要意义。     

Exotic Becomes Erotic: Interpreting the Biological Correlates of Sexual Orientation

Although biological findings currently dominate the research literature on the determinants of sexual orientation, biological theorizing has not yet spelled out a developmental path by which any of the various biological correlates so far identified might lead to a particular sexual orientation. The Exotic-Becomes-Erotic (EBE) theory of sexual orientation (Bem, 1996) attempts to do just that, by suggesting how biological variables might interact with experiential and sociocultural factors to influence an individual's sexual orientation. Evidence for the theory is reviewed, and a path analysis of data from a large sample of twins is presented which yields preliminary support for the theory's claim that correlations between genetic variables and sexual orientation are mediated by childhood gender non-conformity.     

Effects of chronic inhibition of nitric oxide synthase in the genetically hypertensive rat

1. The effects of graded inhibition of nitric oxide synthase (NOS) on blood pressure in the genetically hypertensive (GH) rat strain and NOS activity in regions of the brain (cerebellum, striatum, hippocampus, frontal cortex and medulla oblongata) as a measure of body NOS inhibition were studied. 2. Male GH and normotensive (N) rats (n = 7-10 per group) were given N(G)-nitro-L-arginine methyl ester (L-NAME; 2, 5, 10 or 20 mg/kg per day in drinking water) from age 7 weeks. Age- and weight-matched controls received water only. Systolic blood pressure (SBP) was measured weekly by the tail-cuff method from age 6 weeks. By age 10 weeks, rats were killed and NOS activity was measured. 3. Some GH rats that received over 5 mg/kg per day L-NAME developed stroke-like symptoms and were killed before the end of the treatment period. 4. No difference in NOS activity was found between untreated N and GH strains but, in those that received treatment, a graded inhibition was observed with increasing L-NAME dose levels. The frontal cortex in the GH strain given 20 mg/kg per day L-NAME had NOS inhibition of 90% where the N strain had 73% inhibition. Similar results were seen in the other areas of the brain. 5. Left ventricular mass, weight related, was significantly greater in the GH compared with N and was further elevated by treatment with L-NAME. 6. The SBP at 10 weeks was significantly elevated in GH rats by NOS inhibition with L-NAME in a dose-dependent manner; 25% for 2 mg/kg per day, 31% for 20 mg/kg per day (P < 0.001). There was a non-significant increase in BP in the N-treated groups (average change of 7.5%). 7. Nitric oxide synthase inhibition causing increased SBP in GH rats suggests an abnormality in the nitric oxide-L-arginine pathway in this strain.     

Birth of Healthy Children After Preimplantation Diagnosis of Thalassemias

Background: Preimplantation genetic diagnosis (PGD) allows couples at risk of having children with thalassemia to ensure the healthy outcome of their pregnancy. Methods: Seventeen PGD clinical cycles were initiated for Cypriot couples at risk of having children with different thalassemia mutations, including IVS1-110, IVSI-6, and IVSII-745. Unaffected embryos for transfer were selected by testing oocytes, using first and second polar body (PB) removal and nested polymerase chain reaction analysis followed by restriction digestion. Results: Unaffected embryos were selected in 16 of 17 PGD cycles. Of 166 oocytes studied from these cycles, 110 were analyzed by sequential analysis of both the first and the second PB, resulting in preselection and transfer of 45 unaffected embryos. This resulted in seven pregnancies and in the birth of five healthy thalassemia-free children. The embryos predicted to have inherited the affected allele were not transferred. Analysis of these embryos confirmed the PB diagnosis. Conclusions: Sequential first and second PB testing of oocytes is reliable for PGD of thalassemia and is a feasible alternative to prenatal diagnosis in high-risk populations.     

Preimplantation Genetic Diagnosis Using Fluorescent Polymerase Chain Reaction: Results and Future Developments

Purpose: Fluorescent polymerase chain reaction (PCR) is a multipurpose technique that can be used for diagnosing sex, single-gene defects, and trisomies as well as determining DNA fingerprints from single cells. However, its effectiveness must be assessed before clinical preimplantation genetic diagnosis (PGD) application. Methods: Single and multiplex fluorescent PCR was applied to single cells and blastomeres. Results: Fluorescent PCR can be used to diagnose sex from blastomeres and has been successfully applied in a clinical PGD sexing program resulting in a confirmed pregnancy. A further major advantage of fluorescent PCR is the ability to multiplex, providing multiple diagnoses and DNA fingerprints with a high reliability (~75% for trisomy, 86% for DNA fingerprint) and good accuracy (70–80%). Allele dropout in multiplex PCR is ~20% per allele and does not appear to be associated with the fragment size. Conclusions: Fluorescent PCR is a powerful technique for PGD, and the effects of allele dropout must be considered, particularly in multiplex PCR.     

An Accurate and Rapid Gender Determination Assay in Single Cells by the Capillary Polymerase Chain Reaction Method

Purpose: In preimplantation genetic diagnosis (PGD), a rapid and accurate assay has been required. We have therefore developed a capillary polymerase chain reaction (PCR) method using rapid thermal cycling programs to determine the gender of single amniocytes. Methods: Single amniocytes from each amniotic fluid sample were isolated by micromanipulation and their gender was determined by a multiplex PCR assay in a capillary tube, using primers that amplify a 308-bp DXZ1 and a 154-bp DYZ1 repeat sequence on the X and Y chromosomes, respectively. Results: All four thermal cycling programs, which took 180, 150, 120, and 90 min, were 100% accurate in diagnosing the gender of single amniocytes. No DNA contamination was observed in any samples. Conclusions: The multiplex PCR assay was rapid and accurate in diagnosing gender in single cells and may be clinically applicable in PGD.     

Advantages of Day 4 Embryo Transfer in Patients Undergoing Preimplantation Genetic Diagnosis of Aneuploidy

Purpose: Following preimplantation genetic diagnosis of aneuploidy, embryo transfer was executed on day 4, with the aim of providing more time for expanding from six to nine the number of diagnosed chromosomes per single cell (Group 2; 45 cycles). The results obtained were compared to those derived from conventional day 3 transfer (Group 1; 71 cycles). Methods: For multicolor fluorescence in situ hybridization analysis, two panels of probes were used: the first, specific for chromosomes XY, 13, 16, 18, and 21, was tested in all patients (Groups 1 and 2); the second was implemented only in Group 2 patients for the detection of chromosomes 14, 15, and 22. Results: A total of 406 embryos underwent fluorescence in situ hybridization analysis in Group 1, and 236 in Group 2. Comparable percentages of both chromosomal abnormalities (61% and 62%) and pregnancy and implantation rates (36% and 24.5% in Group 1, 41% and 23.6% in Group 2) resulted, regardless of the higher mean age in Group 2. Conclusions: The diagnosis of the nine chromosomes which are most frequently associated with aneuploidy in humans could have an immediate impact on the rate of spontaneous abortions. Additional advantages are represented by the more accurate morphological evaluation of euploid embryos; the advanced compaction, which means that embryos are less exposed to damage during the transfer procedure; and the possibility of performing a reanalysis in cases where a fluorescence in situ hybridization diagnosis is not obtained.     

Preimplantation Genetic Diagnosis of Aneuploidy: Were We Looking at the Wrong Chromosomes?

Purpose: Our purpose was to study aneuploidy frequencies of chromosomes 1, 4, 6, 7, 14, 15, 17, 18, and 22 in cleavage-stage embryos. These frequencies were compared to spontaneous abortion data to determine differences in survival rate of their aneuploidies. Methods: One hundred ninety-four embryos were analyzed with multicolor fluorescence in situ hybridization. Embryos were divided into three maternal age groups: 20 to 34.9 years, (2) 35 to 39.9 years, and (3) 40 years and older. Embryos were also divided into two developmental and morphological groups: arrested and nonarrested embryos. Results: The rate of aneuploidy was 14.51%, 14.10%, and 31.48% for age groups 1, 2, and 3, respectively (P < 0.005). The chromosomes most frequently involved in aneuploidy events were 22, 15, 1, and 17. Conclusions: The chromosomes most involved in spontaneous abortions are not necessarily the ones causing a decrease in implantation rates with maternal age. Other aneuploidies, such as for chromosomes 1 and 17, may seldom implant or die shortly after implantation.