补中益气汤治疗慢性乙型肝炎的临床与实验研究

通过对补中益气汤及西药治疗慢性乙型肝炎临床疗效的对比研究,发现补中益气汤能较快改善慢性乙型肝炎的临床症状及体征,改善肝功能,促使乙型肝炎病毒血清学标志好转(HBsAg、HBeAg转阴或滴度下降,抗-HBe或抗-HBs转为阳性),与西药治疗对照组比较有显著性差异(P<0.05)。动物实验观察了补中益气汤对小鼠肝组织DNA、RNA、蛋白质合成的影响,结果表明,补中益气汤对三者的合成均有明显的促进作用。其抗肝炎的作用机制可能与该方增强肝脏蛋白质的合成,促进肝组织的修复,改善机体整体的抗病机能有关。     

16株假单胞菌DNA的G＋C百分含量测定

采用改良的热变性温度法，将DNA升温及恒温处理与紫外吸收值的测定分两步进行，检测3株标准菌株和16株假单胞菌DNA的G Cmol% 含量。结果表明，14株假单胞菌与其相应标准菌种的DNAG＋Cmol%含量基本一致，与其生物学性状亦相符；另2株DNA的G＋Cmol%含量与其生物学性状不符，其分类学位置尚待探讨。     

Cerivastatin inhibits fetal calf serunvinduced DNA synthesis in cultured rat mesangial cells

SUMMARY: Inhibition of mevalonate synthesis by several statins has been shown to suppress DNA synthesis in glomerular mesangial cells. In the present study, we investigated the effect of a new statin, cerivastatin, on fetal calf serum (FCS)-induced DNA synthesis of cultured rat mesangial cells. Cultured rat mesangial cells were stimulated by 10% FCS in the presence or absence of cerivastatin and mevalonate. 5-bromo-2-deoxyuridine (BrdU) incorporation was used to assess DNA synthesis. the present study showed that 10% FCS caused marked stimulation of DNA synthesis in the mesangial cells. Cerivastatin inhibited FCS-stimulated BrdU incorporation in a dose-dependent manner. IC₅₀ was approximately 1 umol/L. Exogenous mevalonate, farnesyl pyrophosphate and geranylgeranyl pyrophosphate significantly prevented the inhibitory effect of cerivastatin on DNA replication. It appears that cerivastatin, by inhibiting the synthesis of mevalonate, may suppress DNA synthesis in the mesangial cells.     

Andrology: Application of different in-situ hybridization detection methods for human sperm analysis

The detection of some types of aneuploidy in human spermatozoacan be based on the use of the fluorescence in-situ hybridizationtechnique (FISH). One of the crucial steps for FISH is to achievea proper decondensation and denaturation of the DNA in the specimen,so as to obtain efficient hybridization results. However, afterDNA decondensation the morphology of sperm heads is partly distortedand the majority of the tails is lost. This situation leadsto problems in the distinction between disomic and diploid spermatozoa,as well as between abnormal spermatozoa and somatic cells. Double-and triple-target FISH can partly solve this discriminationproblem. To improve these procedures we adapted the steps ofdecondensation and visualization of the single sperm cells.Firstly, DNA decondensation with 25 mM dithiothreitol in 1 MTris at pH 9.5 resulted in sperm cells with intact morphologyof both the head and the tail, and allowed efficient single-,double- and triple-target ISH to be performed. Secondly, weapplied a novel detection method, based on enzyme immunocyto-chemicalreactions, with coloured precipitation products. Thirdly, thisISH procedure was combined with Diff-Quik staining and bright-fieldmicroscopy. This absorption method has the advantage of a permanentsignal, and the adapted cytoplasmic staining of the sperm plasmamembrane allows the visualization of the outline of the singlespermatozoon. Using this approach, therefore, it is possibleto discriminate between disomic, diploid and abnormal spermatozoa,somatic cells and spermatozoa that overlap, because the morphologyof the cells is not distorted and the tails of the spermatozoaare intact and properly visualized.     

Higher-order organization and compartmentalization of satellite DNA PIM357 in species of the coleopteran genus Pimelia

The PIM357 satellite DNA family is present in 26 Pimelia taxa (Tenebrionidae, Coleoptera) with endemic congeneric species from the Canary Islands showing higher interrepeat variability than continental ones. In this paper, we compare the repetitive DNA sequences of a Canarian species that has distinct subfamilies of repeat units, P. radula ascendens, with another without such subfamilies, P. sparsa sparsa. The chromosomal localization of the repeat units and the comparison of the variability of randomly cloned monomers to the one estimated by comparing repeat units from dimers and trimers suggest the absence of satellite subfamilies in P. sparsa sparsa. Hence, the repeat units of this species seem to be uniformly and randomly distributed throughout all chromosomes out of one chromosomal pair. On the contrary, P. radula ascendens shows four divergent subfamilies of repeat units supported by several diagnostic nucleotide substitutions. These subfamilies seem to form four distinct repeat units: monomer subfamily 1, monomer subfamily 4 and two higher-order units (dimer linking subfamily 1 and 4, and dimer linking subfamily 2 and 3). Moreover, monomers of subfamily 1 are present in three chromosomal pairs only. We discuss the effect of different potential factors acting in the concerted evolution and the genomic organization of stDNA sequences in these taxa. This revised version was published online in July 2006 with corrections to the Cover Date.     

Software compensation improves the analysis of heterogeneous tumor samples stained for multiparameter DNA flow cytometry

Background: High concentrations of propidium iodide (PI), in combination with fluorescein isothiocyanate (FITC) and R-phycoerythrin (RPE) used for multiparameter DNA flow cytometry (FCM), cause spectral cross-talk into the green fluorescence channel (FL1). We have evaluated the use of post-acquisition software compensation (N-Color Compensation) in order to correct this spectral cross-talk caused by PI. Method: Cell mixtures were prepared consisting of keratin 8/18 FITC labeled, keratin 8/18 RPE labeled, and unlabeled MCF-7 breast carcinoma cells. DNA was stained with PI (100 μM). Post-acquisition software compensation was applied to correct the spectral cross-talk of PI fluorescence. Secondly, the distribution of the Ki-67 (FITC) protein during the cell cycle (PI) of SiHa cervical carcinoma cells (no software compensation) was compared to the Ki-67 expression pattern of SiHa cells, simultaneously stained for keratin 8 (RPE), after applying software compensation. Finally, software compensation was used to compare the relative levels of PCNA and p53 expression in two clinical ovarian cancer ascites specimens, stained for PCNA or p53 (FITC), keratin 8/18 (RPE), and DNA (PI), with a known p53 status (positive and negative, respectively). Results: The Ki-67 cell cycle-dependent pattern of a triply stained sample (Ki-67 (FITC), keratin 8 (RPE), and DNA (PI)) is restored after software compensation and the results are comparable to the Ki-67 distribution of a sample stained solely for Ki-67 and DNA. P53 expression could only be resolved after using software compensation in the p53 positive ovarian ascites (OA) sample. Conclusions: We conclude that software compensation is a robust and reliable post-acquisition method for the correction of RPE/PI spectral cross-talk, permitting better identification of weakly expressed proteins in heterogeneous clinical tumor samples stained for multiple cellular antigens and DNA using PI.     

瘢痕疙瘩成纤维细胞p53基因突变的研究

目的　探讨瘢痕疙瘩成纤维细胞中 p5 3基因第 4～ 8外显子的突变规律及其意义。　方法　取瘢痕患者手术切除的瘢痕疙瘩和增生性瘢痕标本各 12例 ,并设患者自身正常皮肤标本及血标本为对照。体外分离、培养上述组织标本的成纤维细胞。采用聚合酶链式反应 单链构象多态性(PCR SSCP)分析方法和基因测序法 ,检测各种组织成纤维细胞中p5 3基因的突变情况。　 结果　 12例瘢痕疙瘩标本中有 9例p5 3基因外显子 4、5、6、7出现点突变和移码突变 ,增生性瘢痕标本、正常皮肤标本及血标本中均未检出突变。　结论　p5 3基因突变是瘢痕疙瘩形成和发展的重要因素之一。     

广东省结核病流行菌株研究

目的：从分子流行病学的角度探讨广东省结核分支杆菌菌株流行的分布。方法：构建广东省74株临床分离的以RFLP为基础的结核分支杆菌的IS6110 DNA指纹图谱技术，确诊结核分支杆菌菌株的流行分布。结果：24．3％（18／74）的结核菌株的IS6110 DNA指纹相似值在1－0．65之间，鉴定结果为它们均是“北京家族”结核分支杆菌菌株。结论：广东省结核菌株流行主要存在着遗传关系接近，在基因水平上相关程度较高的“北京家族”结核分支杆菌菌株，且该家族菌株正以一定的比例在我省流行。     

荧光定量PCR和ELISA检测乙肝病毒的应用比较

目的　探讨荧光定量PCR检测HBV—DNA的应用价值。　方法　从 2 92 0份用ELISA检测乙肝 5项的体检血清标本中 ,抽取 2 88份HBsAg阳性标本及 10 0份全阴标本 ,进行荧光定量聚合酶链式反应 (FQ—PCR)HBV—DNA定量分析。　结果　经FQ—PCR检测 ,80份HBsAg、HBeAg、HBcAb都阳性的标本 ,HBV—DNA阳性率为 10 0 % ( 80 /80 ) ,平均HBV—DNA拷贝数为 2 2× 10 8cp/ml ;164份HBsAg、HbeAb、HBcAb都阳性的标本 ,HBV—DNA阳性率为79 3 % ( 13 0 /164 ) ,平均HBV—DNA拷贝数为 1 5× 10 6cp/ml;12份HBsAg单项阳性的标本 ,HBV—DNA的阳性率为83 3 % ( 10 /12 ) ,平均HBV—DNA拷贝数为 1 6× 10 5cp/ml;10 0份HBsAg、HBsAb、HBeAg、HBeAb、HBcAb都阴性的标本 ,HBV—DNA的阳性率为 2 % ( 2 /10 0 ) ,平均HBV—DNA拷贝数为 4 5× 10 5cp/ml。　结论　FQ—PCR可以检测HBV的感染和复制情况 ,对准确报告HBV感染 ,指导其选择治疗方案和观察疗效具有重要的临床意义     

转基因食品的快速PCR鉴定

用十六烷基-二甲基-乙基-溴化铵(CTAB)法快速高效地从样品中提取了可供分析的基因组DNA,经PCR扩增,鉴定了含有35S启动子和NOS终止子的转基因样品.该方法的灵敏度可达0.1%,并且具有很好的稳定性.