Klinefelter's Syndrome: Hypogonadism,abnormal carbohydrate metabolism. Is it a result of biotin deficiency?

The aetiology of Klinefelter's Syndrome is not known. The causative factor(s) must explain the hypogonadism, low androgen levels, the disordered carbohydrate metabolism and the commonly associated psychiatric conditions. A biotin deficient/dependent state can account for the above. A biotin deficient Klinefelter's Syndrome patients with the above is described. The possible role of biotin in the primary, secondary and tertiary prevention of Klinefelter's Syndrome needs further research.     

核酸杂交反应中影响因素分析

以光敏生物素标记的R3 cDNA克隆为模型,采用正交设计的方法,对影响核酸杂交反应的主要因素:杂交反应温度,反应时间,探针浓度及甲酰胺浓度作了综合性分析。当探针浓度为800μg/L,甲酰胺浓度为10mol/L,50℃杂交反应6h,可获得最高灵敏度(10pg)。     

人血浆凝血酶原和异常凝血酶原的BA-ELISA法检测

应用与凝血酶原及异常凝血酶原有免疫交叉反应的非Ca(Ⅱ)依赖性抗人凝血酶原抗体,建立夹心BA-ELISA法,检测人血浆凝血酶原的最低浓度可达1ng/ml。血浆经皂土和柠檬酸钡吸附处理,除去纤维蛋白原和凝血酶原后,可用本法检出存留于血浆中的微量异常凝血酶原,并测得健康人血浆异常凝血酶原的均值为74.61±19.43ng/ml。本法操作简便,特异性强,重复性好。     

Detection of HBV-DNA by in situ hybridization using a biotin-labeled probe

A biotin-labeled DNA probe specific for hepatitis B virus (HBV) nucleotide sequences was hybridized in situ to liver tissue of 20 patients; 16 were chronic carriers of hepatitis B surface antigen (HBsAg) and 4 had no markers of HBV infection. HBV-DNA was also analyzed in the serum and the liver of these patients by spot and Southern blot hybridization, respectively. Liver specimens from six carriers were positive for HBV-DNA both by in situ and Southern blot hybridization; ten carriers were negative by in situ hybridization, and two of these were positive by Southern blot technique. The staining was granular, mainly cytoplasmic, limited to liver specimens containing replicative forms of HBV-DNA, and associated with detection of HBcAg in hepatocytes by immunofluorescence. The sensitivity of this technique was not sufficient to detect few copies of integrated HBV-DNA. The hybridization procedure was specific, as results were constantly negative in liver specimens of patients without markers of HBV infection, and no reaction was observed using DNA probes lacking HBV-DNA sequences. Detection of HBV-DNA by in situ hybridization, using a biotinylated probe, is a rapid, reproducible, and specific histochemical method. Currently available biotinylated probes are advantageous when absolute sensitivity is not the limiting factor, and they also facilitate studies of the cellular and subcellular distribution of HBV nucleic acids.     

采用IL－6cDNA控针检测人IL－6基因表达

采用缺口平移技术对ＩＬ—６ｃＤＮＡ进行了生物素和同位素标记，证明两种标记的ＩＬ－６ｃＤＮＡ（３０ｎｇ／ｍｌ）均可检出低至５ｐｇ的同源ＤＮＡ，而模拟探针（５００μｇ／ｍｌ）对高达１００ｎｇ的同源序列无此反应。应用ＩＬ－６ｃＤＮＡ对富含ＩＬ－６ｍＲＮＡ的标本进行斑点杂交或Ｎｏｒｔｈｅｒｎ杂交，证明人参三醇皂甙促进了淋巴细胞ＩＬ—６基因表达（４倍），人胎脾单个核细胞、人胎脑组织匀浆和人胎胰岛细胞内均含有高浓度ＩＬ—６ｍＲＮＡ。     

A case of 46,XX,r(X) (p1q1) diagnosed by in situ hybridization

A small marker chromosome was identified as an X-derived ring chromosome by in situ hybridization with a biotinylated X-chromosome specific a-satellite DNA probe. This procedure clearly determined the chromosomal origin of the marker chromosome, which had been impossible to define by conventional cytogenetic techniques including high resolution banding.     

Subcortical auditory input to the primary visual cortex in anophthalmic mice

Anatomical and imaging studies show ample evidence for auditory activation of the visual cortex following early onset of blindness in both humans and animal models. Anatomical studies in animal models of early blindness clearly show intermodal pathways through which auditory information can reach the primary visual cortex. There is clear evidence for intermodal corticocortical pathways linking auditory and visual cortex and also novel connections between the inferior colliculus and the visual thalamus. A recent publication [L.K. Laemle, N.L. Strominger, D.O. Carpenter, Cross-modal innervation of primary visual cortex by auditory fibers in congenitally anophthalmic mice, Neurosci. Lett. 396 (2006) 108–112] suggested the presence of a direct reciprocal connection between the inferior colliculus and the primary visual cortex (V1) in congenitally anophthalmic ZRDCT/An mice. This implies that this mutant mouse would be the only known vertebrate having a direct tectal connection with a primary sensory cortex. The presence of this peculiar pathway was reinvestigated in the ZRDCT/An mouse with highly sensitive neuronal tracers. We found the connections normally described in the ZRDCT/An mouse between: (i) the inferior colliculus and the dorsal lateral geniculate nucleus, (ii) V1 and the superior colliculus, (iii) the lateral posterior nucleus and V1 and between (iv) the inferior colliculus and the medial geniculate nucleus. We also show unambiguously that the auditory subcortical structures do not connect the primary visual cortex in the anophthalmic mouse. In particular, we find no evidence of a direct projection from the auditory mesencephalon to the cortex in this animal model of blindness.     

抗癌胚抗原单抗与生物素及链霉亲和素偶联物的制备及性能鉴定

目的　 研究抗癌胚抗原(CEA)单抗与生物素及链霉亲和素(streptavidin, SA)偶联物的制备方法。方法　 将CEA单抗按抗体与生物素活化酯物质的量之比为1:15～1:50进行生物素化。抗CEA单抗与SA的偶联采用3-（2-吡啶二巯基丙酸）-N-琥珀酰亚胺酯（SPDP）化学偶联法制备。抗CEA单抗偶联物的生物活性及免疫活性分别采用间接ELISA方法和放射免疫分析法进行测定。 结果　生物素化单抗每分子抗体中约偶联3分子生物素,具有良好的SA结合活性,经SDS-PAGE电泳证实为单一蛋白条带,仍保留95%的免疫活性。SA每分子中含有1～2个巯基,而抗CEA单抗每分子中含有2～3个3-（2-吡啶二巯基丙酸）-N-琥珀酰亚胺酯间接ELISA方法证实偶联物具有良好的生物素结合活性, SDS-PAGE电泳显示单抗-SA偶联物相对分子质量为210 000左右,仍保留着原单抗活性的70%左右。结论　所制备的两类抗CEA单抗偶联物基本保持完整的特异性结合肿瘤CEA的性质,可为进一步的预定位显像和治疗应用提供可靠的靶向载体。     

免疫-PCR法检测柯萨奇病毒B组抗原的实验研究

目的：建立免疫－PCR法,对分离培养和柯萨奇B组病毒（CoxB)毒株及临床可疑为CoxB感染的血清标本进行检测。方法：以间日疟原虫SSUrRNA基因为指示分子,采用生物系进行末端标记,利用酶联免疫吸附试验（ELISA）和PCR原理,建立免疫－PCR法,并对60份临床标本进行检测。结果：该方法具有较高敏感性和特异性,其敏感性是ELISA法的3000倍,也高出RT－PCR法10倍。结论：免疫－PCR法是检测CoxB抗原的敏感而特异的方法,为CoxB的临床早期快速鉴定和流行病学研究等提供了一种新的微量抗原检测手段。