Genetic diversity and population structure of the invasive alien red swamp crayfish

High genetic diversity is thought to characterize successful invasive species, as the potential to adapt to new environments is enhanced and inbreeding is reduced. The red swamp crayfish, Procambarus clarkii, native to northeastern Mexico and south-central USA was introduced to Nanjing, China from Japan in 1929. Little is known about the genetic diversity and population structure of this species in China. We examined the genetic diversity and population structure of six P. clarkii populations using nine polymorphic microsatellites. Among the six populations, Nanjing population showed the highest allele number, allele richness and gene diversity, which is consistent with records indicating Nanjing may be the first site of introduction. In all six populations, significant heterozygote deficit was observed, suggesting founder effects and non-random mating. Analysis of bottleneck under infinite allele model, stepwise mutation model and two-phased model of mutation revealed evidence of a recent bottleneck in all these populations. Pairwise genetic distance analysis, AMOVA and assignment tests demonstrated high genetic differentiation between populations. Pairwise genetic distance did not fit the pairwise geographic distance, suggesting that human mediated dispersal have played a role in the population expansion and genetic differentiation.     

Seeing the process of histidine phosphorylation in human bisphosphoglycerate mutase

Bisphosphoglycerate mutase is an erythrocyte-specific enzyme catalyzing a series of intermolecular phosphoryl group transfer reactions. Its main function is to synthesize 2,3-bisphosphoglycerate, the allosteric effector of hemoglobin. In this paper, we directly observed real-time motion of the enzyme active site and the substrate during phosphoryl transfer. A series of high resolution crystal structures of human bisphosphoglycerate mutase co-crystallized with 2,3-bisphosphoglycerate, representing different time points in the phosphoryl transfer reaction, were solved. These structures not only clarify the argument concerning the substrate binding mode for this enzyme family but also depict the entire process of the key histidine phosphorylation as a "slow movie". It was observed that the enzyme conformation continuously changed during the different states of the reaction. These results provide direct evidence for an "in line" phosphoryl transfer mechanism, and the roles of some key residues in the phosphoryl transfer process are identified.     

在胶束非均相体系中竹红菌乙素光敏作用特征的ESR研究

竹红菌乙素（ＨｙｐｏｃｒｅｌｌｉｎＢ,简称ＨＢ）属于脂溶性醌类光敏剂。本文采用近代ＥＳＲ实验技术,探讨了ＨＢ在ＴｒｉｔｏｎＸ—１００胶束非均相体系中光敏反应原初过程的特征。首先证明,在非均相体系中,ＨＢ仍具有产生１Ｏ２的作用,进而证实,ＨＢ通过电子传递亦能产生ＨＢ－,Ｏ２－和·ＯＨ自由基。结果发现,ＨＢ在非均相胶束体系中,上述活性中间体（１Ｏ２和自由基）的相对产额均显著高于均相体系值。这表明,在非均相体系中,ＨＢ光敏反应激发能转移和电子传递具有新的特点和规律。据此推测,ＨＢ在生物非均相体系中的光敏损伤作用将会有新的特征。     

Ectopic expression of a poplar APETALA3-like gene in tobacco causes early flowering and fast growth

A MADS-box gene, designated PtAP3, was isolated from a floral bud cDNA library derived from Populus tomentosa. Analysis by multiple alignments of both nucleotide and amino acid sequences, together with phylogenetic analysis, revealed that PtAP3 is an ortholog of Arabidopsis AP3. Analysis of RNA extracts from vegetative and reproductive tissues of P. tomentosa by RT-PCR indicated that PtAP3 is expressed in roots, stems, leaves and vegetative and floral buds. Notably, the expression of PtAP3 fluctuated during floral bud development between September and February with differences between male and female buds. In the former, a gradual down-regulation during this period, interrupted by a slight up-regulation in December, was followed by a sharper up-regulation on February. In developing female floral buds, expression was stable from September to November, sharply up-regulated in December, and then gradually down-regulated until February. The functional role of PtAP3 was investigated in transgenic tobacco plants. Of 25 transformants, nine displayed an earlier flowering phenotype compared with the wild type plants. Furthermore, transgenic tobacco had faster growth and more leaves than untransformed controls. The traits proved to be heritable between the T0 and T1 generations. Our results demonstrate a regulatory role of the PtAP3 gene during plant flowering and growth and suggest that the gene may be an interesting target for genetic modification to induce early flowering in plants.     

应用血清学方法鉴别急性和慢性病毒性乙型肝炎

本文用ELISA间接法检测急性和慢性乙型肝炎病人血清特异性抗HBcIgG,用ELISA捕捉法检测特异性抗HBcIgM。11例急性乙肝病人急性期抗HBcIgM100％阳性,抗HBcIgG全部阴性;恢复期抗HBcIgM 81.8％阴转,抗HBcIgG则100％阳转。17例慢性乙肝病人抗HBcIgM82.35％阳性,抗HBcIgG 100％阳性。被检血清经密度梯度超速离心,证实抗HBcIgM和抗HBcIgG两类抗体反应在急性和慢性乙肝病人血清中具有不同的动态规律。     

Galectins-3 and -7, but not galectin-1, play a role in re-epithelialization of wounds

Disorders of wound healing characterized by impaired or delayed re-epithelialization are a serious medical problem. These conditions affect many tissues, are painful, and are difficult to treat. In this study, using cornea as a model, we demonstrate for the first time the importance of carbohydrate-binding proteins galectins-3 and -7 in re-epithelialization of wounds. In two different models of corneal wound healing, re-epithelialization of wounds was significantly slower in galectin-3-deficient (gal3(-/-)) mice compared with wild-type (gal3(+/+)) mice. In contrast, there was no difference in corneal epithelial wound closure rates between galectin-1-deficient and wild-type mice. Quantitation of the bromodeoxyuridine-labeled cells in gal3(+/+) and gal3(-/-) corneas revealed that corneal epithelial cell proliferation rate is not perturbed in gal3(-/-) corneas. Exogenous galectin-3 accelerated re-epithelialization of wounds in gal3(+/+) mice but, surprisingly, not in the gal3(-/-) mice. Gene expression analysis using cDNA microarrays revealed that healing corneas of gal3(-/-) mice contain markedly reduced levels of galectin-7 compared with those of gal3(+/+) mice. More importantly, unlike galectin-3, galectin-7 accelerated re-epithelialization of wounds in both gal3(-/-) and gal3(+/+) mice. In corresponding experiments, recombinant galectin-1 did not stimulate the corneal epithelial wound closure rate. The extent of acceleration of re-epithelialization of wounds with both galectin-3 and galectin-7 was greater than that observed in most of the published studies using growth factors. These findings have broad implications for developing novel therapeutic strategies for treating nonhealing wounds.     

Raman spectroscopic characteristics of microcosmic and photosensitive damage on space structure of liposomes sensitized by hypocrellin and its derivatives

Ｈｙｐｏｃｒｅｌｌａｂａｍｂｕｓａｅ(Ｂ.ｅｔＢｒ)Ｓａｃｃ.,ｏｎｅｋｉｎｄｏｆｆｕｎｇｕｓ,ｉｓｐａｒａｓｉｔｉｚｅｄｏｎｔｈｅＳｉｎａｒｕｎｄｉｎａｒｉａｓｐ.ＩｔｇｒｏｗｓａｂｕｎｄａｎｔｌｙｉｎｔｈｅｎｏｒｔｈｗｅｓｔｅｒｎｒｅｇｉｏｎｏｆＹｕｎｎａｎＰｒｏｖｉｎｃｅｏｆＣｈｉｎａ,ａｎｄｈａｓａｌｏｎｇｈｉｓｔｏｒｙｏｆｗｏｒｋｉｎｇａｓａｔｒａｄｉｔｉｏｎａｌｍｅｄｉｃｉｎａｌａｇｅｎｔ[1].Ｉｔｓｐｒｏｍｉｓｉｎｇａｎｔｉｃａｎｃｅｒａｎｄａｎｔｉｖｉｒａｌｆｕｎｃｔｉｏｎｓｈａｖｅｌｅｄ…     

不同批号乙型肝炎血源疫苗的免疫效果

以北京和上海生物制品研究所生产的不同批号的乙型开炎血源疫苗,免疫HBsAg和HBeAg均阳性母亲及HBsAg阴性母亲的新生儿,以及不同年龄的儿童和成人HBV易感者,程序为0、1、6个月。在第一针后9～12个月采血,用RIA法检测抗-HBs,S/N≥10.0为阳性。观察不同批号疫苗兔疫后的抗-HBs阳转率。6个批号的疫苗,以30、10、10μg和30μg×3剂量免疫HBsAg和HBeAg均阳性母亲的新生儿210人,抗-HBs阳转率为74.46％～84.09％,7个批号以10μg×3免疫阴性母亲的新主儿1510人,抗-HBs阳转率为80.29％～96.24％;3个批号以10μg×3免疫易感儿童238人,2号批号以10μg×3疫易感成年人127人,抗-HBs阳转率前者为87％～100.0％,后者为90％～96％。如按S/N≥2.1计算,抗-HBs阳转率可全部达到90％以上。提示我国生产的乙肝疫苗对各年龄人群都有较好的免疫反应,个别批号间有些差异,但经统计处理多无显著意义。     

流感病毒与人流感和禽流感

流行性感冒(简称:流感)是严重危害动物和人类健康的一类疾病,引起流感的罪魁祸首就是流感病毒。以下就流感病毒的生物学性状、致病性、防治等方面的特点加以简述。