African origin of modern humans in East Asia: A tale of 12,000 Y chromosomes

To test the hypotheses of modern human origin in East Asia, we sampled 12,127 male individuals from 163 populations and typed for three Y chromosome biallelic markers (YAP, M89, and M130). All the individuals carried a mutation at one of the three sites.

Toward an understanding of the molecular mechanism for successful blood feeding by coupling proteomics analysis with pharmacological testing of horsefly salivary glands

Horseflies are economically important blood-feeding arthropods and also a nuisance for humans and vectors for filariasis. They rely heavily on the pharmacological properties of their saliva to get a blood meal and suppress immune reactions of hosts. Little information is available on antihemostatic substances in horsefly salivary glands; especially no horsefly immune suppressants have been reported. By proteomics or peptidomics and coupling transcriptome analysis with pharmacological testing, several families of proteins or peptides, which act mainly on the hemostatic system or immune system of the host, were identified and characterized from 30,000 pairs salivary glands of the horsefly Tabanus yao (Diptera, Tabanidae). They are: (i) a novel family of inhibitors of platelet aggregation including two members, which possibly inhibit platelet aggregation by a novel mechanism and act on platelet membrane, (ii) a novel family of immunosuppressant peptides including 12 members, which can inhibit interferon-gamma production and increase interleukin-10 secretion, (iii) a serine protease inhibitor with 56 amino acid residues containing anticoagulant activity, (iv) a serine protease with anticoagulant activity, (v) a protease with fibrinogenolytic activity, (vi) three families of antimicrobial peptides including six members, (vii) a hyaluronidase, (viii) a vasodilator peptide, which is an isoform of vasotab identified from Hybomitra bimaculata, and interestingly (ix) two metallothioneins, which are the first metallothioneins reported from invertebrate salivary glands. The current work will facilitate the understanding of the molecular mechanisms of the ectoparasite-host relationship and help in identifying novel vaccine targets and novel leading pharmacological compounds.

12种鳃形目鱼类mt DNA NI4 L- NI4基因的序列变异及其分子系统学

鳃形目鱼类是一类在鱼类乃至脊椎动物进化史上占有很重要地位的古老濒 危鱼类，长期悬而未决的系统演化关系为世人瞩目.采用DNA测序技术首次测定了 包括中国特有鳃形目鱼类在内的12种鳃形目鱼类的mtDNA ND4L和ND4基因(703 by)的序列，并进行了分子系统学分析.从分子系统学的角度得出了如下结论:(1) 鲤属可以归并到鳃属;(2)达氏鳃与中华鳃的亲缘关系最近，很有可能为中华鳃的 一陆封类型;(3)环太平洋地区的鳃科鱼类可能有共同的起源;(4) ND4L和ND4基 因是进行鳃形目鱼类系统演化研究很好的遗传标记.

Phylogenetic relationships of 12 Penaeoidea shrimp species deduced from mitochondrial DNA sequences

DNA sequences of an 847 bp fragment of mitochondrial cytochrome oxidase subunit I (COI) gene and a 514 bp fragment of 16s rRNA gene were determined to examine the phylogenetic relationships of 12 Penaeoidea shrimp species (Penaeus chinensis, Penaeus japon

鸟类核型研究Ⅻ．雀形目12种

本文在国内首次报道了雀形目８科１２种鸟类染色体核型，其中阔嘴鸟科、河乌科的两科是世界上首次报道核型的科。比较研究表明：臂间倒位以及微小染色体的相互融合在所描述的类群染色体进化中起到重要作用。

Molecular modeling on some human interleukins sharing gamma c of interleukin-2 receptor, and structure-function relationships

Five models for human interleukin-7 (HIL-7), HIL-9, HIL-13, HIL-15 and HIL-17 have been generated by SYBYL software package. The primary models were optimized using molecular dynamics and molecular mechanics methods. The final models were optimized using a steepest descent algorithm and a subsequent conjugate gradient method. The complexes with these interleukins and the common gamma chain of interleukin-2 receptor (IL-2R) were constructed and subjected to energy minimization. We found residues, such as Gln127 and Tyr103, of the common gamma chain of IL-2R are very important. Other residues, e.g. Lys70, Asn128 and Glu162, are also significant. Four hydrophobic grooves and two hydrophilic sites converge at the active site triad of the gamma chain. The binding sites of these interleukins interaction with the common gamma chain exist in the first helical and/or the fourth helical domains. Therefore, we conclude that these interleukins binds to the common gamma chain of IL-2R by the first and the fourth helix domain. Especially at the binding sites of some residues (lysine, arginine, asparagine, glutamic acid and aspartic acid), with a discontinuous region of the common gamma chain of IL-2R, termed the interleukins binding sites (103-210). The study of these sites can be important for the development of new drugs. (C) 2000 Elsevier Science B.V. All rights reserved.

Interaction between human interleukin-16 and CD4 receptor of HIV-1

AIM: To study the interaction between human interleukin-16 (IL-16) and the receptor CD4 (T-lymphocyte differentiation antigen) of human immunodeficiency virus type 1 (HIV-1). METHODS: Two structurally con served regions (SCRs) of human IL-16 were built by the SYBYL/Biopolymer module using the corresponding transmembrane (TM) domain of human interleukin-1 (HIL-4) and HIL-2 as the templates. The coordinates for amino-terminal residue sequence, carboxyl-terminal residue sequences, and cytoplasm loops were generated using Biopolymer's LOOP SEARCH algorithm. RESULTS: HIL-16 first formed a homodimer, then contacted with CD4 dimer further forming a dimeric complex. Subsequently, the dimeric complex constructed the tetrameric complex by two disulfide bridges between the cysteines of HIL-16 (Cys31-Cys31). CONCLUSION: The interaction model is useful to propose the action mechanism of HIL-16 and is beneficial for rational designing of novel anti-HIV drugs.

维生素B_(12)对萼花臂尾轮虫种群的影响

温度为15℃时,添加20,40,80和100μg/mL维生素B12后,萼花臂尾轮虫(Brachionuscalyciflorus)种群密度随时间增加而增长,其回归方程依次为:y=e(0.1757+0.2974x),y=4.6765x1.2079,y=7.7798x1.0175和y=e(0.6117+0.3469x),密度显著高于对照组(t=4.56,8.15,8.53和9.86;P<0.01)。对照组和添加组最大混交雌体百分率依次为57.69,76.09,73.81,60.00和45.15%,最大卵雌比依

固相微萃取与色谱联用方法分析水中12种有机氯化合物

运用顶空固相微萃取与色谱联用方法(HS-SPME-GC)对水中的残留有机氯化合物进行了分析.对影响HS-SPME-GC分析灵敏度的各种实验因素如涂层种类、萃取温度、平衡时间、离子浓度等进行了讨论,并将该方法与固相萃取法(SPE)、液液萃取法(LLE)作了对比;同时考察了常见环境共存污染物直链烷基苯磺酸钠(LAS)对几种方法的影响.