Serum lipoprotein (a) concentrations are inversely associated with T2D,prediabetes, and insulin resistance in a middle-aged and elderly Chinese population

Lipoprotein (a) [Lp(a)], an LDL-like particle, has been proposed as a causal risk factor for CVD among general populations. Meanwhile, both serum Lp(a) and diabetes increase the risk of CVD. However, the relationship between serum Lp(a) and T2D is poorly characterized, especially in the Asian population. Therefore, we conducted a cross-sectional study in 10,122 participants aged 40 years or older in Jiading District, Shanghai, China. Our study found that the prevalence of T2D was decreased from 20.9% to 15.0% from the lowest quartile to the highest quartile of serum Lp(a) concentrations (P for trend <0.0001). Logistic regression analyses showed that the odds ratios and 95% confidence intervals of prevalent T2D for quartiles 2–4 versus quartile 1 were 0.86 (0.73–1.01), 0.88 (0.75–1.04), and 0.76 (0.64–0.90) (P for trend = 0.0002), after adjustment for traditional confounding factors. Moreover, the risks for prevalent prediabetes, insulin resistance, and hyperinsulinemia were also decreased from the lowest to the top quartile. This inverse association between serum Lp(a) and T2D was not appreciably changed after we adjusted hypoglycemic medications or excluded the subjects with hypoglycemic and/or lipid-lowering agents and/or a history of self-reported CVD.     

十二烷基硫酸钠协同微波-酶法提取布渣叶总黄酮

采用十二烷基硫酸钠(SDS)协同微波-酶法提取布渣叶总黄酮,选取微波辐射时间(X1)、SDS质量分数(X2)、液固比(X3)、恒温水浴提取时间(X4)、酶解时间(X5)进行U15(54×3)混合水平均匀试验设计,利用偏最小二乘法(PLS)处理试验数据,建立数学模型,确定提取的最优条件并进行验证;另外,将优化后的提取结果与其他提取方法进行比较.研究结果表明:优化的提取条件为X1=1min、X2=0.16％、X3=30.75 mL/g、X4=50 min、X5=30 min.与其他提取方法相比,该法提取效率高,环保无污染,具有一定的应用价值.     

Identification and characterization of CBL and CIPK gene families in canola (Brassica napus L.)

Background

Canola (Brassica napus L.) is one of the most important oil-producing crops in China and worldwide. The yield and quality of canola is frequently threatened by environmental stresses including drought, cold and high salinity. Calcium is a ubiquitous intracellular secondary messenger in plants. Calcineurin B-like proteins (CBLs) are Ca²⁺ sensors and regulate a group of Ser/Thr protein kinases called CBL-interacting protein kinases (CIPKs). Although the CBL-CIPK network has been demonstrated to play crucial roles in plant development and responses to various environmental stresses in Arabidopsis, little is known about their function in canola.

Results

In the present study, we identified seven CBL and 23 CIPK genes from canola by database mining and cloning of cDNA sequences of six CBLs and 17 CIPKs. Phylogenetic analysis of CBL and CIPK gene families across a variety of species suggested genome duplication and diversification. The subcellular localization of three BnaCBLs and two BnaCIPKs were determined using green fluorescence protein (GFP) as the reporter. We also demonstrated interactions between six BnaCBLs and 17 BnaCIPKs using yeast two-hybrid assay, and a subset of interactions were further confirmed by bimolecular fluorescence complementation (BiFC). Furthermore, the expression levels of six selected BnaCBL and 12 BnaCIPK genes in response to salt, drought, cold, heat, ABA, methyl viologen (MV) and low potassium were examined by quantitative RT-PCR and these CBL or CIPK genes were found to respond to multiple stimuli, suggesting that the canola CBL-CIPK network may be a point of convergence for several different signaling pathways. We also performed a comparison of interaction patterns and expression profiles of CBL and CIPK in Arabidospsis, canola and rice, to examine the differences between orthologs, highlighting the importance of studying CBL-CIPK in canola as a prerequisite for improvement of this crop.

Conclusions

Our findings indicate that CBL and CIPK family members may form a dynamic complex to respond to different abiotic or hormone signaling. Our comparative analyses of the CBL-CIPK network between canola, Arabidopsis and rice highlight functional differences and the necessity to study CBL-CIPK gene functions in canola. Our data constitute a valuable resource for CBL and CPK genomics.     

红树林放线菌分离鉴定及活性代谢产物研究

以采集自四个红树林地点的16份混合土壤为研究材料,选用7种选择性培养基,共分离获得330株放线菌。其中217株菌经16SrRNA基因序列分析,发现近75%菌株属于小单孢菌属(Micromonospora),其他还包括多形态孢菌属(Polymorphospora),疣孢菌属(Verrucosispora)等小单孢菌科的2个属和非小单孢菌科的9个属。采用美蓝酶标仪法对所分离到的放线菌进行抗菌活性检测,共50株菌表现出对金黄色葡萄球菌(Staphylococcus aureus ATCC 51650)、大肠杆菌(Escherichia coli ATCC 25922)和白色念珠菌(Candida albicans ATCC 10231)有不同程度抗性。然后利用高效液相色谱(HPLC)和液质联用技术(LC-MS)对有生物活性的菌株进行化学筛选,最后确定了5株可能产新颖化合物的小单孢菌。     

PCR-Based Seamless Genome Editing with High Efficiency and Fidelity in Escherichia coli

Efficiency and fidelity are the key obstacles for genome editing toolboxes. In the present study, a PCR-based tandem repeat assisted genome editing (TRAGE) method with high efficiency and fidelity was developed. The design of TRAGE is based on the mechanism of repair of spontaneous double-strand breakage (DSB) via replication fork reactivation. First, cat-sacB cassette flanked by tandem repeat sequence was integrated into target site in chromosome assisted by Red enzymes. Then, for the excision of the cat-sacB cassette, only subculturing is needed. The developed method was successfully applied for seamlessly deleting, substituting and inserting targeted genes using PCR products. The effects of different manipulations including sucrose addition time, subculture times in LB with sucrose and stages of inoculation on the efficiency were investigated. With our recommended procedure, seamless excision of cat-sacB cassette can be realized in 48 h efficiently. We believe that the developed method has great potential for seamless genome editing in E. coli.     

Close linkages between leaf functional traits and soil and leaf C:N:P stoichiometry under altered precipitation in a desert steppe in northwestern China

Leaf functional traits are important for characterizing plant nutrient strategies. The C:N:P stoichiometric balance in soils and plants, which could indicate types of nutrient limitation, is altered under changing precipitation patterns. However, whether such alterations affect leaf functional traits remains unclear. We conducted a three-year simulated precipitation experiment in a desert steppe in northwestern China to determine changes in leaf photosynthetic traits and nutrient conservation traits in five plant species and tested the relationships of these traits with soil and leaf C:N:P stoichiometry. The five species showed few changes in their leaf traits under drought conditions, but they adjusted these traits (especially P traits) under extremely wet conditions (50% increase in precipitation). Improved leaf photosynthetic N and P use, lowered leaf P uptake, and enhanced leaf N resorption might help Lespedeza potaninii to rely less on soil nutrients in extremely wet environments than other species do. Leaf photosynthetic traits were regulated primarily by soil and leaf C:N:P stoichiometry. Leaf nutrient conservation traits were controlled by both leaf C:N:P stoichiometry and soil properties (i.e., enzyme activity and microbial biomass), a condition especially true for P traits. The results suggest that precipitation-induced alteration in the C:N:P stoichiometric balance might have important influences on plant nutrient use strategies and even on the nutrient cycling of desert steppes.

     

Development of Colloidal Gold Immunochromatographic Strips for Detection of Riemerella anatipestifer

Riemerella anatipestifer is one of the most important bacterial pathogen of ducks and causes a contagious septicemia. R. anatipestifer infection causes serositis syndromes similar to other bacterial infections in ducks, including infection by Escherichia coli, Salmonella enterica and Pasteurella multocida. Clinically differentiating R. anatipestifer infections from other bacterial pathogen infections is usually difficult. In this study, MAb 1G2F10, a monoclonal antibody against R. anatipestifer GroEL, was used to develop a colloidal gold immunochromatographic strip. Colloidal gold particles were prepared by chemical synthesis to an average diameter of 20±5.26 nm by transmission electron microscope imaging. MAb 1G2F10 was conjugated to colloidal gold particles and the formation of antibody-colloidal gold conjugates was monitored by UV/Vis spectroscopy. Immunochromatographic strips were assembled in regular sequence through different accessories sticked on PVC plate. Strips specifically detected R. anatipestifer within 10 min, but did not detect E. coli, S. enterica and P. multocida. The detection limit for R. anatipestifer was 1×10⁶ colony forming units, which was 500 times higher than a conventional agglutination test. Accuracy was 100% match to multiplex PCR. Assay stability and reproducibility were excellent after storage at 4°C for 6 months. The immunochromatographic strips prepared in this study offer a specific, sensitive, and rapid detection method for R. anatipestifer, which is of great importance for the prevention and control of R. anatipestifer infections.     

安徽省2017-2018年手足口病柯萨奇病毒A6型基因进化特征分析

人肠道病毒A组71型(Enterovirus A71,EV-A71)和柯萨奇病毒A组16型(Coxsackievirus A16,CV-A16)是引起手足口病(Hand,foot,and mouth disease,HFMD)的主要病原体.近年来非EV-A71和非CV-A16的其他肠道病毒(Enterovirus,EV)已成为HFMD流行或暴发疫情的优势病原体.安徽省HFMD监测数据显示,2017-2018年HFMD样本非EV-A71和非CV-A16其他EV核酸阳性率超过50％,其中大部分为柯萨奇病毒A组6型(Coxsackievirus A6,CV-A6).为了解安徽省2017-2018年HFMD其他肠道病毒构成和CV-A6基因进化特征,本研究收集2017-2018年HFMD咽拭子EV核酸阳性标本,采用人横纹肌肉瘤(RD)细胞进行病毒分离培养,对分离到的CV-A6毒株VP1全长序列基因扩增及核苷酸序列测定.从NCBI GenBank数据库下载CV-A6原型株和代表性毒株基因参考序列,运用生物软件MEGA 6.0构建VP1基因序列系统进化树,分析其基因遗传特征.结果 显示,安徽省2017-2018年HFMD实验室确诊病例其他EV占66.1％,CV-A16占23.5％,EV-A71占10.4％.52株CV-A6毒株均为D3a基因亚型,其VP1区核苷酸序列间相似度为93.7％～100％,编码的氨基酸序列相似度为98.3％～100％;与CV-A6 Gdula原型株核苷酸相似度为78％～82.3％,氨基酸相似度为94.6％～96.3％.VP1区15个氨基酸位点有变异,氨基酸位点Q98L和G160S的变异发生率为100％.其他EV已成为安徽省引起HFMD流行的重要病原体,D3基因型CV-A6为优势流行毒株.持续加强其他EV的病原学监测与分析,对安徽省HFMD防控策略制定与疫情处置具有重要意义.