Evaluation of Flow Rate,pH, Buffering Capacity,Calcium, Total Proteins and Total Antioxidant Capacity Levels of Saliva in Caries Free and Caries Active Children: An In Vivo Study

The purpose of this study was to evaluate the relationship between the physicochemical properties of saliva such as flow rate, pH, buffering capacity, calcium level, total protein and total antioxidant levels in caries free and caries active children. The present study included one hundred and twenty healthy children who were divided into two groups; group I and group II comprising of age groups 7–10 and 11–14 years, respectively. Both the groups were then sub-divided equally according to gender. They were further divided into caries free and caries active with 15 children in each group. Unstimulated saliva was collected by suction method and flow rates were determined. The samples were then analyzed for pH, buffering capacity, total protein, calcium and total antioxidant capacity. The data was statistically analyzed using student t test (unpaired). The results revealed that when all these parameters were compared among the caries free and caries active children, flow rate, pH, buffering capacity were slightly reduced in caries active children, but total protein and total antioxidant capacity of saliva increased significantly in caries active children and the total calcium decreased significantly in caries active children. Within the limitation of this study, we conclude that, the physicochemical properties of saliva play a major role in the development of caries.     

植物抗病因子—PR蛋白的研究进展

植物抗病因子是近年来生物学上的研究热点,本文较为详细地介绍了病原相关蛋白的发现、类型、性质、结构、生物学功能、分布以及在植物抗病中的作用,为深入进行这类蛋白的研究提供了参考。     

Bcl-2蛋白家族与运动

Bcl-2蛋白家族根据其在细胞凋亡中的作用,分为抑凋亡蛋白和促凋亡蛋白.在骨骼肌细胞和心肌细胞内,Bcl-2家族成员之间形成二聚体,调节细胞是否进入凋亡程序.不同强度的运动对骨骼肌、心肌和淋巴细胞凋亡的影响不尽相同.     

Effect of anti-epileptic drugs in pregnancy and teratogenesis

Epilepsy raises special concern in women during pregnancy. Antiepileptic drugs are known to induce major and minor malformations in the foetus. Aim of the study was to find an association between maternal serum alpha fetoprotein levels, foetal abnormalities and antiepileptic drugs mediated teratogenicity. Maternal serum alpha feto protein levels, kidney and liver function tests in age matched normal pregnant women and seizure free epileptic pregnant women during 12–14 weeks of gestation were estimated. Cases were subjected to ultrasonography at 11^th–14^th week of pregnancy and again at 20^th week of pregnancy. maternal serum alfa feto protein was assayed by a specific Electro Chemiluminescence Immuno Assay test. There was no significant difference in kidney and liver function tests in cases as compared to controls. There were elevated levels of alpha feto protein in cases as compared to controls but this was not statistically significant. No anomalies were detected in ultrasound reports. Most women had normal full term delivery with healthy children but of low birth weight. No correlation was seen between maternal serum alfa feto protein levels and antiepileptic drug leading to teratogenesis.     

运动性血红蛋白低下大鼠红细胞膜组分和功能的变化

目的:探讨运动性血红蛋白低下时红细胞膜组分和功能变化的规律。对象与方法:将雄性SD大鼠60只,随机分为3组:对照组、跑台运动组、负重游泳组。经跑台或负重游泳训练后,将血红蛋白持续下降的大鼠纳入运动性血红蛋白低下组。取血,制备红细胞悬液,测定红细胞膜磷脂成分、带3蛋白含量、磷脂酰丝氨酸外翻率、阴离子转运功能、葡萄糖转运功能、钠钾ATP酶活性及变形能力。结果:与对照组比较,运动性血红蛋白低下组大鼠磷脂中脑磷脂和卵磷脂丢失较多(p<0.01),带3蛋白含量显著升高。同时,磷脂酰丝氨酸外翻率、红细胞滤过分数显著上升(p<0.01),阴离子转运功能、葡萄糖转运能力、钠钾ATP酶活性均显著下降(p<0.05)。结论:长时间激烈运动通过影响红细胞膜组分和功能,导致红细胞损伤和老化,清除标记增多,膜流变性下降,变形能力减弱,造成红细胞溶血和/或清除增多,发生运动性血红蛋白低下。     

农杆菌介导CSPs基因转化甘蓝型油菜转化体系的研究

以甘蓝型油菜下胚轴为外植体,通过农杆菌介导法,对其遗传转化条件进行了研究,建立了转冷激蛋白(CSPs)的遗传转化体系。结果表明,甘蓝型油菜下胚轴经预培养2d后,用浓度为OD600=0.4的农杆菌菌液侵染90s,再经共培养和愈伤诱导培养,外源基因转化到油菜下胚轴外植体的转化效率高。然后通过PCR检测转化后在筛选培养基上诱导成苗的油菜,初步确定CSPs基因已整合到油菜再生植株中。这为以后其他基因转化到甘蓝型油菜的研究奠定一定的基础。     

A suppressed gene in integument cells of a fiberless seed mutant in upland cotton

A fiberless seed mutant (fl) was identified in a commercial cotton (Gossypium hirsutum L.) variety Xu-Zhou 142 (FL). This phenotype is associated with lack of fiber cell initiation in the outer integument of the ovule, as was characterized by analysis of genes related to fiber differentiation and development. Two genes, fl-E6 and FL-E6, were cloned from fl-integument cells and FL-fiber or integument cells, respectively. Compared with FL-E6, fl-E6 showed a dramatic change in nucleotide sequence: (1) FL-E6 contained a tandem repetitive sequence in which GGCTCA (Gly-Ser) is repeated five times between the 82nd and the 93rd codon from the first ATG codon, while in fl-E6 the same sequence is repeated four times; (2) The fl-E6 gene encodes a polypeptide of 241 amino acids but lacks two codons between the 90th and 93rd codon and three between the 171st and 174th relative to FL-E6; (3) There are also 12 nucleotide substitutions which would result in 7 amino acid differences between fl-E6 and FL-E6. Analysis of RT-PCR and Northerm Blot showed that expression of the fl-E6 gene is suppressed in the fl-integument cells, but highly expressed in FL-fiber cells. The difference between fl-E6 and FL-E6 may be associated with lower expression of fl-E6 in the fl-integument cells. Searches of protein databases with the FL-E6 gene sequence showed similarity to the protein backbones of two arabinogalactan-proteins (AGPs), one from the filtrate of suspension-cultured cells ofPyrus cornmunis (AGPPc2) and the other fromNicotiana alata (AGPNa2). Although the function of the FL-E6 protein in differentiation and development of cotton fiber cells is not known, the data indicate that the mutation of fl-E6 gene from FL-E6 gene may inhibit the fiber cell initiation from epidermal cells of the outer integument of the ovule. Project supported by the National Natural Science Foundation of China (Nos. 39770473 and 30170058), National Program of Plant Gene Transfer (J00-B-002-10), National High Technology Research and Development (863) Program of China (No. 2001AA212081), and Research Program of Ministry of Education of China (No. 0114)     

Integrins mediating bone signal transduction

1.IntroductionInteractionsbetweenbonecellsandtheirextra-cellularmatrix(ECM)arecrucialinregulatingbonecellsadhesion,growth,migration,anddifferentiation.Amongtheseinteractions,thedirectcell-matrixattach-mentisthefundamentalofothercellbehaviors.BiochemicalandmechanicalsignalsfromtheECMcanbetransducedtocellinteriorviasomecell-surfacetransmembranereceptors.Severalfamiliesofreceptorsinvolvingintegrin,cadherin,selectinandimmuno-globulinsuperfamilyarerecognized.Recentstudieshavesuggestedthatintegri…     

Interactions between mycoplasma lipid-associated membrane proteins and the host cells

Mycoplamas are a group of wall-less prokaryotes widely distributed in nature, some of which are pathogenic for humans and animals. There are many lipoproteins anchored on the outer face of the plasma membrane, called lipid-associated membrane proteins （LAMPs）. LAMPs are highly antigenic and could undergo phase and size variation, and are recognized by the innate immune system through Toll-like receptors （TLR） 2 and 6, LAMPs can modulate the immune system, and could induce immune cells apoptosis or death. In addition, they may associate with malignant transformation of host cells and are also considered to be cofactors in the progression of AIDS.