骨形成蛋白-7对人肾小管上皮细胞株HK-2凋亡的影响

研究不同浓度的骨成形蛋白 7(BMP 7)对人近曲小管上皮细胞株HK 2凋亡的影响并初步探讨其可能的机制。应用Hoechst 332 5 8荧光染色、DNA电泳检测凋亡细胞的形态学和生化改变 ,流式细胞仪定量检测细胞的凋亡率 ,并观察凋亡特异性蛋白酶Caspase 3活性变化的情况。结果显示 ,HK 2细胞加入 1 0ng/mlTGF β处理 2 4h后 ,可明显抑制细胞生长并诱导细胞凋亡 ,呈现明显的凋亡形态学改变 ,胞核或核质内可见浓度致密的颗粒状荧光 ,DNA电泳呈现典型的“梯形条带” ,而预先加入 5 0ng/ml、 1 0 0ng/mlBMP 7共处理 2 4h后 ,可减轻TGF β对细胞的抑制作用 ,凋亡细胞亦减少 ,Caspase 3蛋白酶活性明显下降 ,细胞凋亡率下降。提示BMP 7对人肾小管上皮细胞凋亡的具有抑制作用 ,可能是通过抑制Caspase蛋白酶活性而实现的     

氧化修饰低密度脂蛋白在子痫前期中的测定及意义

目的测定氧化修饰低密度脂蛋白(oxLDL)在子痫前期中的变化,探讨其意义。方法采用酶联免疫吸附法(ELISA)测定子痫前期重度组、子痫前期轻度组及对照组血清oxLDL水平。结果(1)3组孕妇血清oxLDL比较,见子痫前期重度组升高(49.35±4.22)μg/d l,与对照组(31.71±3.51)μg/d l比较有显著差异(P<0.01);子痫前期轻度组(39.12±2.37)μg/d l升高,与对照组比较有显著差异(P<0.05);子痫前期重度组与轻度组比较无显著差异(P>0.05)。(2)子痫前期重度组血清oxLDL与收缩压、舒张压呈正相关(r=0.51,P<0.01;r=0.47,P<0.05)。结论研究提示oxLDL可能是子痫前期发病的重要因素。     

Construction and characterization of three region-specific microdissection libraries for human chromosome 18

Three region-specific libraries for the entire human chromosome 18 were constructed using microdissection and MboI linker-adaptor microcloning techniques. The libraries included 18pter-p11.1 (designated 18P library), 18q 11.1-q12.3 (18Q1 library), and 18q21.1-qter (18Q2 library). Samples of the microclones from each library were analyzed in detail. The insert sizes ranged between 50–600 bp, with a mean of 180–220 bp for the three libraries. The libraries contained approximately 40–60% microclones with unique sequence inserts. More than 30 unique sequence microclones from each library were analyzed by Southern blot hybridization to demonstrate that they are human specific and were derived from chromosome 18. The human gemomic HindIII fragments hybridized to each microclone were determined and microclones crosshybridized to rodent species were identified. These region-specific libraries and the unique sequence microclones from the libraries are useful reagents for (1) isolating hughly polymorphic microsatellite markers for refined linkage analysis, (2) identifying corresponding YAC, BAC or other clones with large inserts for contig assembly and high resolution physical mapping, (3) isolating cDNA clones from the dissected region, and (4) convenient sequencing of the microclones to prepare high density markers and sequence-tagged sites (STSs). Such applications have been demonstrated in a series of similarly constructed microdissection libraries from other regions of the human genome.     

A follow-up linkage study supports evidence for a bipolar affective disorder locus on chromosome 21q22

Evidence for linkage between bipolar affective disorder (BP) and 21q22 was first reported by our group in a single large pedigree with a lod score of 3.41 with the PFKL locus. In a subsequent study, with denser marker coverage in 40 multiplex BP pedigrees, we reported supporting evidence with a two-point lod score of 2.76 at the D21S1260 locus, about 6 cM proximal to PFKL. For cost-efficiency, the individuals genotyped in that study comprised a subset of our large pedigree sample. To augment our previous analysis, we now report a follow-up study including a larger sample set with an additional 331 typed individuals from the original 40 families, improved marker coverage, and an additional 16 pedigrees. The analysis of all 56 pedigrees (a total of 862 genotyped individuals vs. the 372 genotyped previously), the largest multigenerational BP pedigree sample reportedly analyzed to date, supports our previous results, with a two-point lod score of 3.56 with D21S1260. The 16 new pedigrees analyzed separately gave a maximum two-point lod score of 1.89 at D21S266, less than 1 cM proximal to D21S1260. Our results are consistent with a putative BP locus on 21q22.     

慢性癫痫模型动物海马内GABA能神经元的超微结构改变

用马桑内酯诱发小鼠性性癫痫模型，借助免疫电镜方法对海马的ＧＡＢＡ能神经元的超微结构进行观察，可见小鼠海马内ＧＡＢＡ免疫反应阳性神经元弥散分布于除锥体细胞层和颗粒细胞层外的各部。慢性癫痫上鼠海马内的ＧＡＢＡ免疫反应性神经元胞体和末梢均呈现程度不同的结构损伤，包括线粒体肿胀，细胞器崩解和神经末梢变性，ＧＡＢＡ样轴突末梢可与免疫反应阴性的树突构成传出性轴－树突触，也可接受免疫反应阴性轴末梢的传入性轴－轴     

Breakpoint clusters of the PML gene in acute promyelocytic leukemia: Primary structure of the reciprocal products of the PML-RARA gene in a patient with t(15;17)

DNA studies of the translocation t(15;17) in acute promyelocytic leukemia (APL) have shown that the retinoic acid receptor alpha (RARA) gene on chromosome 17 is juxtaposed to the promyelocytic leukemia (PML) gene on chromosome 15. The PML breakpoints have been mapped to 3 clusters: bcr1, bcr2, and bcr3. We have examined the PML breakpoint distribution in a series of 33 Chinese patients with APL Twenty-two patients fell within bcr1, 2 within bcr2, and 9 within bcr3. The primary structure of the reciprocal chromosome translocation joints of one patient and that of their normal counterparts have been determined and compared to those of 2 previously reported cases. These studies revealed possible topoisomerase II cleavage sites close to the breakpoints and suggested implications of DNA attachment sites to nuclear matrix. We propose that these features are relevant to the process of illegitimate recombination generating the translocation. © 1993 Wiley-Liss, Inc.     

"Waste" follicular aspirate from fertility treatment--a potential source of human germline stem cells?

Fertility clinics worldwide routinely produce a large volume of 'waste' follicular aspirate, which is potentially an abundant source of immature ovarian follicles. Current attempts to cultivate these further in vitro to yield viable mature oocytes for fertility treatment have not yet achieved much success. Instead, recent lines of evidence have emerged that are suggestive of a potential stem cell niche within such immature ovarian follicles. The recent discovery of follicular renewal and putative germ-line stem cells within the postnatal mammalian ovary shook the foundations of reproductive biology by challenging the established dogma that mammalian females lose the capacity for germ cell renewal during fetal life, such that a fixed reserve of germ cells (oocytes) enclosed within follicles is endowed at birth. More intriguingly, another recent study in the Drosophila model provided compelling evidence that somatic progenies (nurse cells) of germ-line stem cells had the ability to revert back to the stem-cell-like state. This introduces the exciting possibility that within the mammalian ovarian follicle, similar somatic progenies of germ-line stem cells may also possess a greater intrinsic ability to revert back into functional stem cells. If this is the case, then a favored candidate would be the cumulus/granulosa of immature ovarian follicles, since such cells are true homologues of nurse cells found within the Drosophila ovary. The successful elucidation of a human germ-line stem cell niche within immature ovarian follicles is likely to have huge ramifications in stem cell biology and regenerative medicine.