以agr基因为靶点快速检测金黄色葡萄球菌方法的建立

旨在建立一种以agr基因为靶点,快速检测金黄色葡萄球菌的环介导等温扩增（LAMP)方法。针对金黄色葡萄球菌附属基因调控基因agr序列,设计了4条特异性引物;优化了LAMP体系中甜菜碱、dNTP浓度、长短引物比等因素;通过对14株不同金黄色葡萄球菌菌株和4株其他常见食品致病菌株进行检测,评估引物特异性。结果表明,在Mg²⁺浓度为2.4 mmol/L,dNTP浓度为0.8 mmol/L,甜菜碱浓度为0.1 mol/L,长短引物比为1:8,65 ℃反应50 min条件下扩增可达最佳效果。优化后的LAMP对14株金黄色葡萄球菌均表现为阳性,对4株非金黄色葡萄球菌菌株表现为阴性,证明引物具有特异性。本文首次利用agr基因作为靶基因片段,建立了一个简单、快速、特异性强的检测金黄色葡萄球菌的方法,在食品安全检测方面极具意义。     

Effects of Rhododendron removal and prescribed fire on bees and plants in the southern Appalachians

Rhododendron maximum is an evergreen shrub native to the Appalachian Mountains of North America that has expanded in recent decades due to past disturbances and land management. The purpose of this study was to explore how bees and plants were affected by the experimental removal of R. maximum followed by a prescribed fire in one watershed compared to a neighboring reference watershed. Bees and plants were sampled for three years in both watersheds. Comparisons were based on the rarefaction and extrapolation sampling curves of Hill numbers as well as multivariate methods to assess effects on community composition. Bee richness, Shannon''s diversity, and Simpson''s diversity did not differ between watersheds in the year after removal but were all significantly higher in the removal watershed in year two, following the prescribed fire. Bee Shannon''s diversity and Simpson''s diversity, but not richness, remained significantly higher in the removal watershed in the third year. Similar but weaker patterns were observed for plants. Comparisons of community composition found significant differences for bees in the second and third year and significant differences for plants in all three years. For both groups, significant indicator taxa were mostly associated with the removal watershed. Because bees appeared to respond more strongly to the prescribed fire than to the removal of R. maximum and these benefits weakened considerably one year after the fire, clearing R. maximum does not appear to dramatically improve pollinator habitat in the southern Appalachians. This conclusion is underscored by the fact that about one quarter of the bee species in our study area were observed visiting R. maximum flowers. The creation of open areas with wildflowers may be a better way to benefit bees in this region judging from the high diversity of bees captured in the small roadside clearings in this study.     

海南红厚壳花香气成分采集和TCT-GC-MS分析

用鲜花循环式动态顶空技术采集红厚壳鲜花的香气成分,TCT-GC-MS联用技术分析鉴定。4-羟基-2-丁酮,双烯酮,1、2-环氧-2-甲基丁烷,1、2-环氧-3-甲基丁烷,2-乙基戊烷,3-己醇,甲基环戊烷,2-丁醇等24个成分被检测出,占总离子流出峰面积的90.28%。并对结果进行了分析讨论。     

The New Perspectives on Genetic Studies of Type 2 Diabetes and Thyroid Diseases

Recently, genome-wide association studies (GWAS) have led to the discovery of hundreds of susceptibility loci that are associated with complex metabolic diseases, such as type 2 diabetes and hyperthyroidism. The majority of the susceptibility loci are common across different races or populations; while some of them show ethnicity-specific distribution. Though the abundant novel susceptibility loci identified by GWAS have provided insight into biology through the discovery of new genes or pathways that were previously not known, most of them are in introns and the associated variants cumulatively explain only a small fraction of total heritability. Here we reviewed the genetic studies on the metabolic disorders, mainly type 2 diabetes and hyperthyroidism, including candidate genes-based findings and more recently the GWAS discovery; we also included the clinical relevance of these novel loci and the gene-environmental interactions. Finally, we discussed the future direction about the genetic study on the exploring of the pathogenesis of the metabolic diseases.     

人干细胞生长因子Ca2+依赖糖识别结构域缺失突变体的重组表达及生物学活性的初步探讨

本作已有的研究结果证明,完整的人干细胞生长因子(hSCGF)没有种属特异性,即可以作用于小鼠骨髓造血细胞。这一点与在Ca^2 依赖糖识别结构域(CRD)缺失了78个氨基酸残基的截短分子(hSCGFβ)有所不同。本研究从hSCGF全长cDNA中完全删除了CRD结构域编码序列,进一步探讨CRD结构域的生物学功能。由于该突变体序列GC含量较高．因此将该缺失突变体序列克隆在GST融合表达载体中进行融合表达。通过低温(28℃)诱导,表达产物主要以可溶蛋白的形式存在。利用亲和层析纯化CRD结构域完全缺失的hSCGF突变体融合蛋白,通过检测重组突变分子的协同刺激造血活性有无改变来初步探讨CRD结构域在hSCGF分子中的生物学功能。研究结果表明,去掉完整CRD结构域的突变分子仍然具有造血刺激活性。据此推断CRD结构域在hSCGF分子中可能对于受体配体结合起辅助作用。     

辽宁本溪中三叠统林家瓣轮叶(新种)

在对中国东北辽宁本溪中三叠统林家组的化石研究中,发现了木贼目瓣轮叶属一个新种——林家瓣轮叶(Lobatannularia linjiaensis sp. nov.)。该种叶轮小,明显分成两瓣,每瓣叶数约10–12枚。叶线形至倒披针形,叶长差别大,叶联合长度占叶长约1/3–3/4。自1927年Kawasaki建立瓣轮叶属以来,该属已至少发现了33种,其中大部分报道于二叠纪,少数见于三叠纪。瓣轮叶属作为晚古生代华夏植物群孑遗分子之一,当前该属新种的发现不仅丰富了瓣轮叶属的分类多样性,而且拓展了对二叠纪-三叠纪之交生物大灭绝及之后复苏过程中瓣轮叶属演化趋势的认识。     

Hepatic oxidative DNA damage correlates with iron overload in chronic hepatitis C patients

Hepatic oxidative stress occurs in chronic hepatitis C (CH-C), but little is known about its producing mechanisms and precise role in the pathogenesis of the disease. To determine the relevance of hepatic oxidatively generated DNA damage in CH-C, 8-hydroxy-2'-deoxyguanosine (8-OHdG) adducts were quantified in liver biopsy specimens by immunohistochemical staining, and its relationship with clinical, biochemical, and histological parameters, and treatment response was assessed in 40 CH-C patients. Hepatic 8-OHdG counts were significantly correlated with serum transaminase levels (r=0.560, p=0.0005) and histological grading activity (p=0.0013). Remarkably, 8-OHdG levels were also significantly related to body and hepatic iron storage markers (vs serum ferritin, r=0.565, p=0.0004; vs hepatic total iron score, r=0.403, p=0.0119; vs hepatic hepcidin messenger RNA, r=0.516, p=0.0013). Baseline hepatic oxidative stress was more prominent in nonsustained virological responder (non-SVR) than in SVR to interferon (IFN)/ribavirin treatment (50.8 vs 32.7 cells/10(5) microm2, p=0.0086). After phlebotomy, hepatic 8-OHdG levels were significantly reduced from 53.4 to 21.1 cells/10(5) microm2 (p=0.0125) with concomitant reductions of serum transaminase and iron-related markers in CH-C patients. In conclusion, this study showed that hepatic oxidatively generated DNA damage frequently occurs and is strongly associated with increased iron deposition and hepatic inflammation in CH-C patients, suggesting that iron overload is an important mediator of hepatic oxidative stress and disease progression in chronic HCV infection.     

Four New C19-Diterpenoid Alkaloids from Aconitum nagarum Stapf

Four new aconitine-type C₁₉-diterpenoid alkaloids, were isolated from the roots of Aconitum nagarum Stapf which were named as nagarutines A–D ( 1–4 ), together with eleven known compounds ( 5–15 ). The structures of the compounds were identified by IR, HR-ESI-MS, 1D and 2D NMR spectra. All compounds were tested for the inhibitory effect on LPS induced NO production in RAW 264.7 macrophages, compound 7 showed moderate anti-inflammatory activity effect and Inhibition rate is about 44.50%.     

Effect of daily salinity fluctuation on the intraspecific interactions of a euhalophyte (Suaeda salsa) along a salinity gradient

每日盐度波动对真盐生植物盐地碱蓬种内相互作用沿盐度梯度的影响 土壤盐度的异质性是河口潮间带的一个突出的环境特征,影响植物的生长和盐沼中生物相互作用的转变。本研究旨在探究盐度梯度和盐度波动对一种真盐生植物的种内相互作用的交互影响。     

动物线粒体核质基因互作的研究进展

线粒体是重要的细胞器,为细胞的生命活动提供能量,线粒体的正常功能是核基因和线粒体基因共同作用维持的结果。线粒体DNA是动物细胞内唯一存在的核外遗传物质,线粒体DNA与核基因的相互作用维持着线粒体和线粒体内膜呼吸链氧化磷酸化的正常功能状态。本文就线粒体核质基因互作在人类疾病、衰老、细胞凋亡、氯霉素抗性、ANT、MnSOD、mtTFA的研究进展进行了综述。 Abstract：Mitochondria is the essential element for a cell,in which generates energy.The normal functions of a mitochondria are controlled by both mitochondrial genome and nuclear genome.Mitochondrial DNA is the only genome in the cytoplasmy of a cell,it encodes essential components of oxidative phosphorylation(OXPHOS)in mitochondrial inner membrane,generating cellular energy in the main form of adenosine triphosphate(ATP).In this paper,we reviewed the research development on interactions of nuclear and mitochondrial genes,including human disease and aging,apoptosis,chloromycetin resistance,ANT,MnSOD and mtTFA.