杀线虫放线菌DA09202的鉴定及其活性物质的解析

从海南热带植物园土壤样品中分离获得一株具有较强杀线虫活性的放线菌菌株DA09202,通过形态特征、生理生化特征、16SrDNA序列测定及其系统发育分析,初步鉴定为金色链霉菌。菌株DA09202发酵液采用溶媒萃取、硅胶柱层析、Sephadex LH-20凝胶过滤和制备薄层板层析,从中分离得到杀线虫活性化合物A23-1和A46-2。化合物A23-1经光谱和波谱分析(UV、1H-NMR、13C-NMR、DEPT、1H-1HCOSY、HMBC、HSQC)以及文献对照,鉴定为4′,7-二羟基异黄酮,化合物A46-2的结构正在鉴定中。     

乳腺癌中雌激素受体α表达水平调节的分子机制

雌激素受体α(ERα)在乳腺癌的发生发展中扮演重要角色,因而ERα成为乳腺癌治疗的分子靶标。ERα的表达水平在乳腺癌患者中差异较大,即使同一患者,在乳腺癌的不同阶段也可能有很大的差别。乳腺癌内分泌治疗的疗效以及预后都与ERα表达水平密切相关。影响ERα表达水平的分子机制复杂,众多调节分子在染色质、转录、转录后、翻译和翻译后等水平参与ERα表达水平的调节。在染色质和转录水平,许多分子通过直接或间接地与ERα启动子的相互作用改变ERα的转录;在转录后/翻译水平,一些microRNA通过诱导ERαmRNA的降解和/或抑制其翻译降低ERα的水平;在翻译后水平,许多分子通过泛素-蛋白酶体途径调节ERα蛋白水平。文章从不同水平,对这些调节分子的调节机制进行简要综述。     

夏季舟山渔场及邻近海域浮游动物群落结构特征分析

2006年8月在舟山渔场及邻近海域（29°30′ ～31°30′ N,124°30′ E以西）开展海洋生态系统综合调查,用浅水Ⅰ型浮游生物网采集的浮游动物样本,对该海域浮游动物的种类组成、数量分布、生物多样性等群落结构特征进行了分析。结果得知,在调查海域共鉴定出浮游动物93种（不包含浮游幼虫）,其中以桡足类的种类数为最多,有50种,优势种主要有精致真刺水蚤（Euchaeta concinna）、软拟海樽（Dolioletta gegenbauri）、肥胖箭虫（Sagitta enflata）、百陶箭虫（Sagitta bedoti）、中华哲水蚤（Calanus sinicus）、普通波水蚤（Undinula vulgaris）、微刺哲水蚤（Canthocalanus paupe）、长尾类幼虫（Macruran larvae）、双生水母（Diphyes chamissonis）、背针胸刺水蚤（Centropages dorsispinatus）、肥胖三角溞（Evadne tergestina）、太平洋纺锤水蚤（Acartia pacifica）等12种。调查海域浮游动物丰度平面分布呈现南部高、北部低,近岸高、外海低的特征。生物多样性分析表明,调查海域浮游动物种类数较多,且具有较高的均匀度（0.70）,因此其生物多样性指数较高（4.98）。根据聚类分析结果,可将夏季调查海域的浮游动物在17.13%相似性水平上分为A、B、C三个组群。生物−环境匹配分析显示,浮游动物的丰度除了与表层盐度、硝酸氮和硅酸盐含量有关外,还与镉、铅的含量存在着一定相关性。     

No significant association between Fc receptor-like 3 gene polymorphisms and human leukocyte antigen-B27 positive ankylosing spondylitis in Han Chinese population

Ankylosing spondylitis (AS) is a rhematoid arthritis, which is a common autoimmune disease with a complex genetic etiology. Although HLA-B27 has been identified to be associated with AS, a number of other genes may also be involved in the disease. Fc receptor-like 3 (FCRL3) gene has been shown to be associated with rheumatoid arthritis in Japanese population. Here we aim to explore the association FCRL3 gene and susceptibility to human leukocyte antigen (HLA)-B27-positive AS in Han Chinese population. Among 169 AS patients, the frequencies of C and T (rs7522061) in FCRL3 gene were 38.7 and 61.3%, respectively; in 184 controls (HLA-B27-positive), the frequencies of C and T were 38.6 and 61.4%, respectively. The frequencies of alleles and genotype are not of statistically significant difference in two groups (χ² = 0.000, P = 0.983; χ² = 0.099, P = 0.952, respectively),but the distribution of HLA-B27 subtypes are statistically significant difference between cases and controls (χ² = 8.214, P = 0.042). Our data reveal that the FCRL3 gene does not appear associated with susceptibility to HLA-B27-positive AS in Han Chinese population.     

The quantitative research of composite immune indicator for crustacean

Through analyzing the immunity indicators in recent crustacean research, two defects are pointed in comprehensive immunity evaluation, 1) the integrant indicators cannot comprehensively reflect the change of immunity, and 2) the conclusions that obtained from different indicators of immunity level cannot be compared objectively and scientifically. Basing on that, the paper firstly indicated that the immunity system could be regarded as a composite indicator. Secondly, the paper gave the specific definition of the composite immunity indicator (CII), and discussed the methods of calculation, especially provided two calculation methods of the weights, that is, the Analytic Hierarchy Process (AHP) and the Principal Component Analysis (PCA). Finally, examples were given to clarify the specific steps to compute the composite immunity indicator. The computing results gave the quantitative evaluation, which were in concordance with the existing conclusions.     

Molecular cloning and expression of two HSP70 genes in the Wuchang bream (Megalobrama amblycephala Yih)

Two complementary deoxyribonucleic acid (cDNA) clones encoding heat shock cognate 70 (HSC70) and inducible heat shock protein 70 (HSP70) were isolated from the liver of Wuchang bream (Megalobrama amblycephala Y.) using RT-PCR and rapid amplification of cDNA ends (RACE). They were named Ma-HSC70 and Ma-HSP70, respectively. The cDNAs were 2336 and 2224 bp in length [not including poly (A)] and contained 1950 and 1932 bp open reading frames (ORFs), respectively. The ORFs encoded proteins of 649 and 643 amino acids with predicted molecular weights of 71.24 and 70.52 kDa, and theoretical isoelectric points of 5.25 and 5.30, respectively. Genomic DNA structure analysis revealed that Ma-HSC70 gene contained seven introns with all introns conforming to the GT/AG rule whereas Ma-HSP70 gene did not contain any intron in the coding region. Amino acid sequence analysis indicated that both Ma-HSC70 and Ma-HSP70 contained three signature sequences of HSP70 family, two partial overlapping bipartite nuclear localization signal sequences (NLS) and cytoplasmic characteristic motif (EEVD). Homology analysis revealed that Ma-HSC70 shared more than 93.0% identity with the known HSC70s of other vertebrates, while Ma-HSP70 shared more than 85.0% identity with the known HSP70s of other vertebrates, and Ma-HSC70 and Ma-HSP70 shared 86.5% identity. Bioinformatics analysis indicated that the proteins encoded by Ma-HSC70 and Ma-HSP70 genes were hydrophilic, rich in B cells antigenic sites, without any signal peptide or transmembrane region. The two proteins also contained many protein kinase C phosphorylation sites, N-myristoylation sites, casein kinase II phosphorylation sites, and N-glycosylation sites, predicting that they could play essential roles in protein folding, translocation, intracellular localization, signal transduction and regulation. The predominant secondary structures of the two proteins were α-helix and random coil. Fluorescent real-time quantitative RT-PCR was used to study the effects of heat shock (34 °C), crowding stress (100 g L^?1) and challenge with bacteria Aeromonas hydrophila on the mRNA expression of the two HSP70s in Wuchang bream liver. The results indicated that, during 24 h stress, Ma-HSC70 mRNA expression decreased at first and then rose to the level before stress under heat shock and crowding stress, but Ma-HSP70 mRNA expression increased at first and then decreased under heat stress, and appeared to increase continuously under crowding stress. After bacterial challenge, the mRNA levels of both Ma-HSC70 and Ma-HSP70 increased at first and then decreased. The cloning and expression analysis of the two HSP70s provide theoretical basis to further study the mechanism of anti-adverseness and expression characteristics under stress conditions of Wuchang bream.     

Re‐Evaluation of the EUK516 Probe for the Domain Eukarya Results in a Suitable Probe for the Detection of Kinetoplastids,an Important Group of Parasitic and Free‐Living Flagellates

ABSTRACT. Two frequently used universal eukaryote probes, EUK1209 and EUK516, are not consistent with one branch of the eukaryotic phylogenetic tree, the Kinetoplastida, which has undergone rapid evolution of their small subunit rRNA gene. Kinetoplastids include medically important parasitic organisms (e.g. Trypanosoma, Leishmania) and free‐living flagellates that occur in all aquatic environments and in soils (e.g. Bodo, Neobodo, Rhynchomonas). A modified probe presented here as KIN516, now based on the kinetoplastid sequence, provides a strong signal with Neobodo designis, Leishmania donovani, and Trypanosoma cruzi using the catalyzed reporter deposition protocol. EUK516 and KIN516 function as competitor probes, thereby greatly increasing discriminatory power when used in combination. The probe pair was tested in field samples collected in a freshwater pond in Norfolk, the mesohaline Elizabeth River, Norfolk, Virginia, and a tropical lagoon in Belize. The combined probes bound to 58–84% of organisms identified as eukaryotic based on having large DAPI‐stained nuclei. The contribution of kinetoplastids to total eukaryotes (positive signal of EUK516+KIN516) was much higher in marine samples (ca. 17%) than in either the freshwater or brackish water sites (<0.2%).     

Biotransformation of eugenol by suspension cultures of transgenic crown galls of <Emphasis Type="Italic">Panax quinquefolium</Emphasis> and suspension cultures of <Emphasis Type="Italic">Nicotiana tabacum</Emphasis>

The biocatalytic ability of transgenic crown galls of Panax quinquefolium was evaluated by using eugenol (1) as a substrate and suspension cultures of Nicotiana tabacum as control system. Three biotransformed products, namely: 2-methoxy-4-(2-propenyl)phenyl-O-β-d-glucopyranoside (2, 67.11%), 2-methoxy-4-(2-propenyl)phenyl-O-β-d-glucopyranosyl (6′ → 1″)-β-d-xylopyranoside (3, 2.85%) and methyl eugenol (4, 14.30%) were obtained after 5 days of administration of eugenol to the suspension cultures of transgenic crown galls of P. quinquefolium. In contrast, only one product, compound 2 (15.41%), was obtained in suspension cultures of N. tabacum after 5 days of incubation. The results indicated that the glycosylation ability of transgenic crown galls of P. quinquefolium was much higher than that of the cultured cells of N. tabacum.