亚硒酸钠对巨噬细胞内游离Ca2+和Mg2+的影响

用单细胞阳离子测定系统研究了SeO^2-₃对巨噬细胞内游离Ca²⁺和Mg²⁺的影响.实验结果表明:SeO^2-₃高于10^-4mol/L时,有显著的细胞毒性.SeO^2-₃对细胞的毒性作用使细胞内游离Ca²⁺和Mg²⁺的浓度升高但Ca²⁺浓度的升高速率比Mg²⁺快.还有,高于10^-4mol/L的SeO^2-₃对红细胞膜上的Ca²⁺-ATP酶活性有明显抑制作用.     

外源DNA直接导入受体植物的研究进展

外源ＤＮＡ直接导入技术以ＤＮＡ片段杂交假说为理论基础,直接将带有目的性状的供体遗传物质（总ＤＮＡ）或目的基因导入受体植株,创造大量的变异材料,通过筛选获得目的性状的后代,达到改良品种的目的。由于其简单、易行、不受受体植物种类的限制,已被越来越多的育种工作者所接受,并在水稻、小麦、棉花、大豆、玉米以及蔬菜等方面得到广泛的应用,为农业生产培育出了一些抗病、抗虫及其它优良性状听新品种及新品系,有利地推动     

Visualizing the microtubule-associated protein tau in the nucleus

Although tau is mainly known as an axonal microtubule-associated protein,many studies indicate that it is not restricted to this subcellular compartment.Assessing tau’s subcellular distribution,however,is not trivial as is evident from transgenic mouse studies.When human tau is over-expressed,it can be immunohistochemically localized to axons and the somatodendritic domain,modeling what is found in neurodegenerative diseases such as Alzheimer’s disease.Yet,in wild-type mice,despite its abundance,tau is difficult to visualize even in the axon.It is even more challenging to detect this protein in the nucleus,where tau has been proposed to protect DNA from damage.To establish a framework for future studies into tau’s nuclear functions,we compared several methods to visualize endogenous nuclear tau in cell lines and mouse brain.While depending on the fixation and permeabilization protocol,we were able to detect nuclear tau in SH-SY5Y human neuroblastoma cells,we failed to do so in N2a murine neuroblastoma cells.As a second method we used subcellular fractionation of mouse tissue and found that in the nucleus tau is mainly present in a hypophosphorylated form.When either full-length or truncated human tau was expressed,both accumulated in the cytoplasm,but were also found in the nuclear fraction.Because subcellular fractionation methods have their limitations,we finally isolated nuclei to probe for nuclear tau and found that the nuclei were free of cytoplasmic contamination.Together our analysis identifies several protocols for detecting tau in the nucleus where it is found in a less phosphorylated form.     

QTL mapping of economically important traits in Silkworm (Bombyx mori)

The construction of linkage map is both a funda-mental research area and an important aspect of gene analyses in genetics. It provides the guidelines for breeding. A sound linkage map is also necessary for further genetic analysis. In recent years, great and rapid progress has been made in molecular biology, which enables fingerprinting of organisms at the ge-nomic level. Many molecular marker techniques have been well established. Heartening progress has been made in many organisms in the co…     

不同倍性小麦和玉米不同群体杂交诱导小麦单倍体的研究

自从Ｚｅｎｋｔｅｌｅｒ等［１］首先报道了小麦×玉米受精现象以来,许多学者对六倍体普通小麦与玉米杂交进行了广泛的研究,获得单倍体的普通小麦,并筛选到一些杂交亲和性较高的亲本材料［２］。但四倍体小麦与玉米杂交研究报道较少。ＯＤｏｎｏｕｇｈｕｅ等用四倍体小麦与玉米杂交获得单倍体胚［３］。随后,Ａｍｒａｎｉ等［４］和孙敬三等［５］利用这一方法相继获得四倍体小麦的单倍体苗。本文报道了不同倍性的小麦基因型与玉米不同群体杂交对诱导小麦单倍体的影响１　材料和方法１．１　亲本材料用作母本的二倍体小麦有一粒小麦（…     

间隔子修饰引物对扩增产物电泳行为的作用初探

目的:初步研究利用C3Spacer间隔子修饰引物对扩增产物电泳行为的影响及作用。方法:选取1个常用短串联重复序列(STR)位点,利用间隔子修饰该位点荧光标记引物,以DNA标准物质为模板进行PCR扩增,记录相应扩增产物DNA片段长度,进行修饰与长度变化的相关性分析。结果:选取STR位点D13S317,分别利用TTTTC3SpacerC3Spacer、TTTTC3Spacer、TTTT修饰R0X标记引物,相应扩增产物长度为182.67±0.05、182.19±0.11和181.6±0.19bp,未进行修饰的对照组引物扩增产物长度为177.09±0.15 bp,产物DNA片段长度随不同修饰基团的修饰发生规律性变化。结论:发现了一种修饰基团,用该基团修饰引物后,可在体外通过PCR反应改变扩增产物等位基因片段的大小,从而在不改变特异性引物信息的前提下使产物发生规律性位移,修饰基团与DNA片段大小呈内在相关性。     

妊娠合并恶性肿瘤疾病的诊疗探讨

目的:探讨妊娠合并恶性肿瘤在诊治过程中的临床表现,探讨其对妊娠结局的影响及预后.方法:回顾性查阅2005年至2011年9月于我院住院治疗患者病历,收集妊娠合并恶性肿瘤疾病患者10例在入院诊断、治疗经过中的相关资料.结果:10例患者中9例在终止妊娠前确诊,3例孕妇死亡,5例在随访中,2例失访;10例胎儿中有生机儿5例,其中1例放弃,在可随访的3例新生儿生存状态良好.结论:妊娠合并恶性肿瘤疾病的临床确诊及及时治疗对妊娠结局会造成影响,妊娠结局与肿瘤分期及孕周相关,应在产前进行常见恶性肿瘤疾病的筛查,早期发现,早期干预.     

线粒体基因突变与NIDDM发生的关系

采用PCR-SSCP、PCR-RFLP及PCR产物直接测序等技术对90例NIDDM(即非胰岛素依赖型糖尿病)及80例正常对照个体的血细胞线粒体DNA进行了突变分析。结果在2例患者中发现线粒体DNA(mitochondrial DNA,mtDNA) ND1 (NaDH Dehydrogenase subunitⅠ)基因上3316位点存在G→A的点突变,导致丙氨酸错义突变成苏氨酸,而在80例正常对照个体中均不存在此位点突变。国内外已证实的和1.5%NIDDM发生有关的mtDNA tRNA Leu^(UUR)|基因上3243位点A→G的突变在本实验中并未发现。由此推断,3316位点G→A的突变可能与NIDDM的发生在关,3243位点A→G的突变率确实很低,可见糖尿病的发生在线粒体遗传上具有广泛的异质性。 Abstract:Using PCR-SSCP,PCR-RFLP and PCR product direct sequencing techniques,we analysed the mitochondrial DNAs(mtDNAs)of 90 patients with NIDDM (Non Insulin-Dependent Diabetes Mellitus)and those of 80 normal controls.The results showed that a G to A mutation which leads alanine’s missence mutaton to threonine in the mitochondrial ND1(NaDH Dehydrogenase subunit I) gene at nucleotide pair 3316 occurred in the blood cells of 2 patients.We have not however,indentified with the A to G mutation at nucleotide pair 3243 of the mitochondrial tRNA Leu(UUR) gene,which has been reported to associate with NIDDM in about 1.5% of the diabetic population.We infer that the mutation at position 3316 is perhaps associated with the development of NIDDM,the occurance of the mutation at position 3243 is actually rare,and NIDDM has an intensive mitochondrial genetic heterogenous background.     

The herbal compound geniposide rescues formaldehyde-induced apoptosis in N2a neuroblastoma cells

The herbal medicine Tong Luo Jiu Nao(TLJN)contains geniposide(GP)and ginsenoside Rg1 at a molar ratio of 10:1.Rg1 is the major component of another herbal medicine,panax notoginseng saponin(PNS).TLJN has been shown to strengthen brain function in humans,and in animals it improves learning and memory.We have previously shown that TLJN reduces amyloidogenic processing in Alzheimer’s disease(AD)mouse models.Together this suggests TLJN may be a potential treatment for patients with dementia.Because chronic damage of the central nervous system by formaldehyde(FA)has been presented as a risk factor for age-associated cognitive dysfunction,in the present study we investigated the protective effect of both TLJN and GP in neuron-like cells exposed to FA.FA-exposed murine N2a neuroblastoma cells were incubated with TLJN,its main ingredient GP,as well as PNS,to measure cell viability and morphology,the rate of apoptosis and expression of genes encoding Akt,FOXO3,Bcl2 and p53.The CCK-8 assay,cytoskeletal staining and flow cytometry were used to test cell viability,morphology and apoptosis,respectively.Fluorescent quantitative real-time PCR(qRT-PCR)was used to monitor changes in gene expression,and HPLC to determine the rate of FA clearance.Treatment of N2a cells with 0.09 mmol L?1 FA for 24 h significantly reduced cell viability,changed cell morphology and promoted apoptosis.Both TLJN and GP conferred neuroprotection to FA-treated N2a cells,whereas PNS,which had to be used at lower concentrations because of its toxicity,did not.Our data demonstrate that TLJN can rescue neuronal damage caused by FA and that its main ingredient,GP,has a major role in this efficacy.This presents purified GP as a drug or lead compound for the treatment of AD.