Effects of starvation on morphometric characteristics of olive flounder, <Emphasis Type="Italic">Paralichthys olivaceus</Emphasis>

An experiment was conducted for 12 weeks to determine the effect of feeding and starvation on truss and classical parameters in the external body of olive flounder, Paralichthys olivaceus. There was an increase in the truss dimension of body depth in the trunk region of the fed group at the end of the experiment (P < 0.05). In the olive flounder, the trunk region dimensions, including body depth measurements, are likely to be compromised by variability related to differences in the feeding of fish from different habitats. Classical dimensions in relation to the anterior–posterior body axis decreased and classical dimensions of head characteristics increased upon starvation but decreased upon feeding (P < 0.05). These results suggest that these morphometric parameters may be a useful index of nutritional status in olive flounder.     

虫草多型现象的5.8S rDNA 和ITS2 序列测定研究

新定名的甘肃虫草Cordycepsgansuensi与冬虫夏草Cordycepssinensi形态相似。蛹虫草Cordycepsmilitaris具有拟青霉型（Paecilomyces-type）和轮枝孢型（Verticillium-type）两类无性型。此研究对5.8SrRNA基因及ITS2间区DNA序列的分析结果表明,甘肃虫草和冬虫夏草的DNA序列相同,属于同一种;蛹虫草的两类无性型具有分子水平上的遗传趋异性。     

两株毛筒腔菌属真菌逆转人乳腺癌细胞多药耐药性

高水平的多药耐药性（multidrug resistance,MDR）基因在肿瘤细胞中过量表达是肿瘤细胞耐药的内在原因,是导致肿瘤化疗失败的主要原素。寻求一种抑制MDR活性的抑制剂是提升抗肿瘤药物药效的重要途径。本研究采用低浓度持续诱导方法建立人乳腺癌细胞（MCF-7）耐药细胞系,结果显示,阿霉素（ADM）、紫杉醇和顺铂对MCF-7耐药细胞系有交叉耐药性,耐药指数（resistance index,RI）分别为5.11、3.55和1.79。菌株对肿瘤细胞的逆转活性筛选表明,红棕毛筒腔菌Tubeufia rubra PF02-2和河池毛筒腔菌T. hechiensis XSL05具有逆转肿瘤细胞多药耐药性为敏感性的活性,逆转倍数（reversion fold,RF）分别为3.79和1.07。结果表明,T. rubra和T. hechiensis具有开发为MDR逆转剂的潜能。     

虫生真菌研究中的一些昆虫学问题

针对当前虫生真菌研究过程中存在的一些昆虫学问题,文章从虫草Cordyceps sensu lato和虫霉Entomophthorales这两类虫生真菌出发,对物种名称的规范、虫生真菌的发生与寄主昆虫生物学之间的关系以及寄主昆虫的鉴定等方面展开讨论,并提出解决方案和推论,旨在深入了解虫生真菌的一些生物学问题。     

Molecular diagnosis for a Tamarix species from two reclaimed lands along the Yellow Sea in Korea inferred from genome wide SNP markers

The taxonomy and phylogenetic relationships of related taxa are important for understanding the biology of a species. Also, spatial distribution of genetic variation may offer insights into history of range shifts and demographic changes. The genus Tamarix L. from the Old World is a taxonomically challenging group that has widely expanded its range in the recent past. We examined genomic diversity patterns and the taxonomic identities of Korean Tamarix species whose taxonomy has remained unresolved. We used a total of 1773 SNP data from genotyping by sequencing for 37 Tamarix plants representing two species; T. chinensis and T. ramosissima to infer species delimitation and the geographic distribution of genomic diversity. Clustering (STRUCTURE; PCA, neighbor joining) and phylogenetic tree results indicated that the two morphologically similar species T. chinensis and T. ramosissima are genetically distinct and the two Korean populations (Sihwa & Songdo) are clustered closely with T. chinensis. Approximate Bayesian Computation based hypothesis testing results suggested that one of the two Korean populations, Songdo might have primarily been derived from the native area, China, followed by range expansion to Sihwa with a secondary admixture event between an established population, Songdo, and a native population, Beijing.     

Education as a predictor of chronic periodontitis: a systematic review with meta-analysis population-based studies

Background

The impact of socioeconomic inequalities on health is well-documented. Despite the links of periodontal disease with cardiovascular diseases, adverse pregnancy outcomes and diabetes, no meta-analysis of socioeconomic variations in periodontal disease exists. This meta-analytic review was conducted to determine the extent to which education attainment influences risk of periodontitis in adults aged 35+ years in the general population.

Methods

The authors searched studies published until November 2010 using EMBASE and MEDLINE databases. References listed were then scrutinised, our own files were checked, and, finally, we contacted experts in the field. The authors included only general population-based studies conducted in adults aged 35 years and more. All articles were blind reviewed by two investigators. In the case of disagreement, a third investigator arbitrated. Using PRISMA statement, two reviewers independently extracted papers of interest.

Results

Relative to the higher education group, people with low education attainment experience a greater risk of periodontitis (OR: 1.86 [1.66–2.10]; p<0.00001). The association was partially attenuated after adjustment for covariates (OR: 1.55 [1.30–1.86]; p<0.00001). Sensitivity analyses showed that methods used to assess periodontitis, definition of cases, study country and categorization of education are largely responsible for the heterogeneity between studies. No significant bias of publication was shown using both the Egger (p = 0.16) and rank correlation tests (p = 0.35).

Conclusions

In the studies reviewed, low educational attainment was associated with an increased risk of periodontitis. Although this evidence should be cautiously interpreted due to methodological problems in selected studies, efforts to eliminate educational inequalities in periodontitis should focus on early life interventions.     

Incoming RNA Virus Nucleocapsids Containing a 5′-Triphosphorylated Genome Activate RIG-I and Antiviral Signaling

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Highlights? RIG-I is activated by the incoming RNA virus nucleocapsids during infection ? RIG-I activation requires a 5′triphosphate dsRNA structure on the nucleocapsids ? Viral nucleocapsids trigger conformational switching and oligomerization of RIG-I ? RIG-I directly binds to viral nucleocapsids containing a 5′triphosphate dsRNA structure     

蓝舌病毒释放机制的研究进展

蓝舌病毒(Bluetongue virus,BTV)作为由媒介昆虫库蠓传播的引起反刍动物蓝舌病(Bluetongue,BT)的病原微生物,同时也是研究无囊膜病毒(Non-enveloped virus)释放机制的经典模型。文中以BTV侵染细胞及组装为始,对BTV诱导细胞自噬并通过多囊泡体以细胞外囊泡形式释放、BTV诱导细胞凋亡而裂解释放、BTV从质膜出芽释放的不同途径以及BTV关键非结构蛋白NS3在调控BTV释放过程中作用机制的研究进展进行综述,为进一步了解BTV感染、增殖、释放的分子机制提供参考。     

A Novel Agarolytic β-Galactosidase Acts on Agarooligosaccharides for Complete Hydrolysis of Agarose into Monomers

Marine red macroalgae have emerged to be renewable biomass for the production of chemicals and biofuels, because carbohydrates that form the major component of red macroalgae can be hydrolyzed into fermentable sugars. The main carbohydrate in red algae is agarose, and it is composed of d-galactose and 3,6-anhydro-l-galactose (AHG), which are alternately bonded by β1-4 and α1-3 linkages. In this study, a novel β-galactosidase that can act on agarooligosaccharides (AOSs) to release galactose was discovered in a marine bacterium (Vibrio sp. strain EJY3); the enzyme is annotated as Vibrio sp. EJY3 agarolytic β-galactosidase (VejABG). Unlike the lacZ-encoded β-galactosidase from Escherichia coli, VejABG does not hydrolyze common substrates like lactose and can act only on the galactose moiety at the nonreducing end of AOS. The optimum pH and temperature of VejABG on an agarotriose substrate were 7 and 35°C, respectively. Its catalytic efficiency with agarotriose was also similar to that with agaropentaose or agaroheptaose. Since agarotriose lingers as the unreacted residual oligomer in the currently available saccharification system using β-agarases and acid prehydrolysis, the agarotriose-hydrolyzing capability of this novel β-galactosidase offers an enormous advantage in the saccharification of agarose or agar in red macroalgae for its use as a biomass feedstock for fermentable sugar production.