亚成体大熊猫肠道真菌多样性

【目的】分析5只亚成体大熊猫肠道真菌的多样性。【方法】采用基于ITS基因的RFLP(Restriction Fragment Length Polymorphism)方法,对肠道真菌总DNA进行ITS-RFLP分析,构建ITS克隆文库,然后用HhaI、HaeIII进行酶切指纹图谱分析,测序并绘制系统进化树。【结果】研究表明,5只亚成体大熊猫肠道真菌主要由Ascomycota(平均占46.24%)、Basidiomycota(平均占15.79%)2个门和一些未分类(平均占29.14%)、未培养(平均占8.83%)的真菌。其中,Ascomycota主要以Saccharomycetes(平均占63.74%)和Dothideomycetes(平均占35.91%)2个纲为主;Basidiomycota主要以Tremellomycetes(平均占65.80%)和Microbotryomycetes(平均占33.15%)2个纲为主。而这4个纲分别则主要以Candida、Debaryomyces;Pleosporales、Myriangium;Cystofilobasidium、Trichosporon;Leucosporidium、Leucosporidiella八个菌属为主,各样品中所占比例不等。【结论】亚成体大熊猫肠道内存在一定比例的真菌菌群,且ITS-RFLP技术能够很好地对其多样性进行分析。真菌的发现扩大了我们对大熊猫肠道微生物结构的了解,同时也有助于我们进一步研究真菌能否帮助大熊猫消化高纤维素食物。     

条斑紫菜抗高温和快速生长细胞株系HB的建立及栽培

本文主要应用单细胞培养技术培育紫菜新品系,以建立紫菜细胞工程快速育苗系统。通过酶解技术分离出紫菜叶状体细胞,并进行多克隆,从中获得4个细胞纯系植株(HA,HB,HC,HD)。对该4个细胞株系进行了纯系培养,并对其细胞苗和丝状体的生长速度和抗高温(19℃,21℃,23℃,25℃)性进行了测定。结果显示,船株系具有较高的抗高温性和最快生长速度。在1998年到2000年间,在江苏省启东县海丰海区对HB株系进行了海上栽培实验,结果显示,实验组的产量高于当地对照组产量,证明了条斑紫菜船株系不仅具有较高的抗高温性,而且也有较快生长速度。本实验说明应用细胞工程进行条斑紫菜育种是一条很好的快速育种途径。     

Kosteletzkya virginica, a halophytic species with potential for agroecotechnology in Jiangsu Province, China

Kosteletzkya virginica (L.) Presl. is a perennial dicot halophytic species, that grows in brackish portions of coastal tidal marshes of the mid-Atlantic and southeastern United States. New saline mudflats have been increasing every year in Northern Jiangsu, China. In 1993, we introduced K. virginica (L.) into China from the Halophyte Biotechnology Center (University of Delaware, USA) as a potential species to improve the soil and develop ecologically sound saline agriculture. Our nearly 10 years of experimental research, both in a test garden and in the field, indicated that K. virginica adapts excellently to the heavy saline soils of Jiangsu Province, China. The average seed yield of K. virginica in 2001 at Yancheng was 638 kg/ha from 1-year old seedlings. There were significant variations among individuals from the unselected population of K. virginica on growth, quality, and seed yield traits. There is great potential to increase the seed yield if superior clones are selected. The seed yield of 35 selected individuals was six times greater than that of the average. Four growth traits of K. virginica were found to have a significant correlation with seed yield. However, there was no strong positive or negative correlation among seed quality traits. The mean seed weight and the germination ratio of the 35 selected individuals of K. virginica were 16.36±0.32 g and 76.11±1.82%, respectively. The percentage content of oil and crude protein in the seeds was 11.28±0.67 and 8.17±0.19%, respectively. The percentage of seed vigor of the selected individuals was 99%, as determined by soft X-ray radiography.     

The α-<Emphasis Type="SmallCaps">l</Emphasis>-fucosidase from <Emphasis Type="Italic">Sulfolobus solfataricus</Emphasis>

Glycoside hydrolases form hyperthermophilic archaea are interesting model systems for the study of catalysis at high temperatures and, at the moment, their detailed enzymological characterization is the only approach to define their role in vivo. Family 29 of glycoside hydrolases classification groups α-l-fucosidases involved in a variety of biological events in Bacteria and Eukarya. In Archaea the first α-l-fucosidase was identified in Sulfolobus solfataricus as interrupted gene expressed by programmed −1 frameshifting. In this review, we describe the identification of the catalytic residues of the archaeal enzyme, by means of the chemical rescue strategy. The intrinsic stability of the hyperthermophilic enzyme allowed the use of this method, which resulted of general applicability for β and α glycoside hydrolases. In addition, the presence in the active site of the archaeal enzyme of a triad of catalytic residues is a rather uncommon feature among the glycoside hydrolases and suggested that in family 29 slightly different catalytic machineries coexist.     

Chromium Status and Glucose Tolerance in Saudi Men With and Without Coronary Artery Disease

Chromium deficiency is associated with impaired glucose tolerance (IGT) and dyslipidemia. Hence, the objective of the current study was to investigate chromium status among Saudi men with and without established cardiovascular disease (CVD) and its relationship to glucose tolerance, lipid profile and other established CVD risk factors. We measured serum and urine chromium concentrations, fasted lipid profile, plasma glucose, and serum lipid peroxide in 130 Saudi men with an established history of myocardial infarction and 130 age-matched controls without established CVD. Patients with established CVD had higher serum triglycerides (p < 0.05) and plasma glucose (p < 0.0001) and lower serum and urinary chromium concentrations (p < 0.0001) than controls. Serum chromium was inversely correlated with plasma glucose among cases and controls (r = −0.189, p < 0.05 and r = −0.354, p < 0.00001, respectively). Plasma glucose (OR 1.127, CI 1.0–1.269, p < 0.05), serum chromium (OR 0.99, CI 0.985–0.995, p < 0.0001), and urinary chromium (OR 0.988, CI 0.981–0.995, p < 0.001) were independently associated with the presence of established coronary disease applying this model. While chromium metabolism appears to be altered in individuals with CVD, it is unclear whether chromium supplementation would be effective in CVD prevention among patients with IGT. This would need to be tested in long-term outcome trials.     

Diverse origins of enzymes involved in the biosynthesis of chloroplast peptidoglycan

Chloroplasts are believed to be descendants of ancestral cyanobacteria that had peptidoglycan layer between the outer and the inner membranes. Historically, the glaucophyte Cyanophora paradoxa and the rhizopod Paulinella chromatophora were believed to harbor symbiotic cyanobacteria having peptidoglycan, which were conventionally named “cyanelles”. In addition, the complete set of genes involved in the synthesis of peptidoglycan has been found in the moss Physcomitrella patens and some plants and algae. The presence of peptidoglycan-like structures was demonstrated by a new metabolic labeling technique in P. patens. However, many green algae and all known red algae lack peptidoglycan-related genes. That is the reason why we questioned the origin of peptidoglycan-synthesizing enzymes in the chloroplasts of the green algae and plants. We performed phylogenetic analysis of ten enzymes involved in the synthesis of peptidoglycan exploiting the Gclust homolog clusters and additional genomic data. As expected, all the identified genes encoded in the chromatophore genome of P. chromatophora were closely related to cyanobacterial homologs. In the green algae and plants, only two genes, murA and mraY, were found to be closely related to cyanobacterial homologs. The origins of all other genes were diverse. Unfortunately, the origins of C. paradoxa genes were not clearly determined because of incompleteness of published genomic data. We discuss on the probable evolutionary scenarios to explain the mostly non-cyanobacterial origins of the biosynthetic enzymes of chloroplast peptidoglycan: A plausible one includes extensive multiple horizontal gene transfers during the early evolution of Viridiplantae.     

六种检测猪瘟病毒方法的比较

【目的】本研究旨在比较6种检测猪瘟病毒方法的优缺点。【方法】应用病毒分离、胶体金免疫层析试纸条、抗原捕捉ELISA、反转录-聚合酶链式反应(RT-PCR)、TaqMan荧光定量RT-PCR(RT-qPCR)和反转录-环介导等温扩增方法(RT-LAMP)等6种方法,分别对50份疑似猪瘟病料中的猪瘟病毒(Classical swine fevervirus,CSFV)进行检测。【结果】结果表明:RT-qPCR和RT-LAMP方法检出阳性样品数为13份,RT-PCR为11份,病毒分离为10份,抗原捕捉ELISA为9份,胶体金试纸条为8份;6种方法均检测为阳性8份,均为阴性37份。【结论】结果提示,在对猪瘟病毒进行检测时,RT-qPCR、RT-LAMP和RT-PCR由于其灵敏性高,可作为首选检测方法,但操作时需要避免假阳性的出现;病毒分离方法虽然操作繁琐,但结果准确,是确诊猪瘟必不可少的检测方法;抗原捕捉ELISA和胶体金试纸条检测时间较短,由于其敏感性较低所限,主要用于对畜群进行检测,不适合个体检测。     

Involvement of Matrix Metalloproteinases on the Inhibition of Cells Invasion and Migration by Emodin in Human Neuroblastoma SH-SY5Y Cells

Emodin (1,3,8-trihydroxy-6-methylanthaquinone), an active component present in the root and rhizome of Rheum palmatum L. (Polygonaceae) has anti-bacterial, anti-tumor, diuretic and vasorelaxant effects. However, its mechanism of action on the cell migration and invasion of human neuroblastoma cancer SH-SY5Y cells is not fully understood. In this study, firstly, the effects of emodin on the percentage of viable cells were examined by using MTT assay and it was found that emodin induced dose-and time-dependent inhibition in human neuroblastoma SH-SY5Y cells. Second, the effects of emodin on the migration and invasion of SH-SY5Y cells were examined by using wound assay and matrigel counting and the results showed that emodin suppressed the migration and invasion of SH-SY5Y cells. Third, we examined the effect of emodin on the levels of associated proteins by using Western blotting and the results indicated that emodin inhibited the levels of GRB2, RhoA, HIF-1α, VEGF, FAK, iNOS, COX2, p-p38, p-c-jun, MMP2, MMP9 and MMP7 but promoted the levels of PKC, PI3K, MEKK3 and NF-κB p65 that led to the inhibition of migration and invasion of SH-SY5Y cells in vitro.     

中国云南巨须隐翅虫亚属的新种和新纪录(鞘翅目,隐翅虫科,巨须隐翅虫亚科)(英文)

报道中国云南巨须隐翅虫属Oxyporus Fablicius和巨须隐翅虫亚属subgenus Oxyporus的4个种,其中包括2新种,玉龙巨须隐翅虫Oxyporus (Oxyporus) yulong sp.nov.和李氏巨须隐翅虫O.(O.)lii sp.nov.,补充了仙台巨须隐翅虫O.germanus Sharp和横沟巨须隐翅虫O.transversesulcatus Bernhauer新的地理分布。