Elevated Serum and Cerebrospinal Fluid Free Fatty Acid Levels Are Associated with Unfavorable Functional Outcome in Subjects with Acute Ischemic Stroke

The aim of this study was to evaluate the prognostic value of serum and cerebrospinal fluid (CSF) free fatty acid (FFA) levels in a cohort of patients with an acute ischemic stroke (AIS). In a prospective study, FFA levels were measured using an enzyme cycling method on admission in serum and CSF of 252 consecutive patients with AIS. The prognostic value of FFA to predict the functional outcome and mortality within 90-day was compared with the National Institutes of Health Stroke Scale score and with other known outcome predictors. Serum and CSF levels of FFA increased with increasing severity of stroke as defined by the NIHSS score (all P?<?0.001). Patients with an unfavorable outcomes and non-survivors had significantly increased FFA serum and CSF levels on admission (all P?<?0.0001). Multivariate logistic regression analysis adjusted for common risk factors showed that serum FFA ≥0.71 mmol/L (third quarters) was an independent predictor of functional outcome (odds ratios (OR)?=?4.86; 95 % confidence interval (CI) 2.26–10.48) and mortality (OR?=?7.72; 95 % CI 3.01–21.48). The area under the receiver operating characteristic curve of serum FFA was 0.79 (95 % CI, 0.72–0.86) for functional outcome and 0.86 (95 % CI, 0.78–0.94) for mortality. Similarly, CSF FFA level also was an indicator for predicting of functional outcome and mortality. FFA levels in serum and CSF may serve as independent biomarkers in addition of the traditional methods for assessing the functional outcome and mortality of AIS.     

突变级数法在厦门城市生态安全评价中的应用

针对港湾快速城市化地区存在的潜在突变特性,基于P-S-R(压力-状态-响应)框架和突变级数法,构建了评价城市生态安全的突变模型,并对1996—2006年厦门城市生态安全进行了评价.结果表明：1996—1998年,快速城市化对厦门市区域生态安全的影响不大,研究区生态安全状况呈上升趋势;1998—2001年,由于大范围高强度的填海造地、人口激增等生态干扰远远超过了生态系统自身的修复能力,导致厦门城市生态安全状况呈快速下降趋势;2001—2006年,厦门城市生态安全整体水平回升,主要受其海湾型生态城市重大战略转变的影响;2006年,研究区系统压力安全级别为Ⅲ,说明厦门市还存在着生态安全隐患.突变级数法反映了单一指标极值情况对生态系统突变的影响,弥补了现有方法在此方面的不足,它既减小了权重赋值的主观性,又避免了主观判断安全标准的不确定性,可准确地反映城市生态安全的发展趋势.     

“两广二号”家蚕抗病毒基因Bmlipase-1和BmSP-2克隆与原核表达

本研究以优良杂交品种"两广二号"家蚕为试材,克隆了该杂交品种家蚕两个抗家蚕核型多角体病毒(BmNPV)基因:脂肪酶基因Bmlipase-1和丝氨酸蛋白酶基因BmSP-2,测序并分别与不同品种蚕的同源基因序列进行比较。结果显示,"两广二号"家蚕Bmlipase-1基因ORF长度为885bp,编码294个氨基酸,BmSP-2扩增长度为855bp,编码284个氨基酸;它们的核苷酸和推导氨基酸序列同源性皆达92%以上,Bmlipase-1更保守,同源性大于99%";两广二号"家蚕的Bmlipase-1基因脂肪酶活化部位和BmSP-2基因酶催化三联体位点的氨基酸残基与不同品种蚕的完全相同。以上结果说明这两个抗病毒基因在蚕的遗传进化过程中高度保守,提示其可能在机体消化或者免疫防御方面起着重要生理作用。将这两个抗病毒基因在大肠杆菌BL21中进行融合表达,获得的融合Bmlipase-1和BmSP-2蛋白分子量分别为47kD和42kD左右。     

蚜科专化菌努利虫疠霉菌种超低温储存

虫霉目真菌的活力对超低温储存较为敏感。储存法在大范围应用前,需对储存效果进行详细评估。将蚜科专化菌努利虫疠霉以初级分生孢子形式（2－3′105个孢子/mL）在-80℃超低温存储12个月。结果显示日常用于培养该真菌的含0.1%乳化芝麻油的萨氏培养基作为超低温保护基质能有效地储存努利虫疠霉孢子,比常见的冷冻保护剂如二甲亚砜和甘油的效果好。孢子悬液经解冻和培养后可获得最多的生物量,而且菌种保持了较高的生长速率。更重要的是,萨氏培养基的主要成分4%葡萄糖、1%蛋白胨和1%酵母粉在低温存储过程中发挥了协同作用,能保     

苦丁茶冬青的RAPD影响因素及实验条件的优化

以苦丁茶冬青为材料研究随机扩增多态DNA(RAPD)的影响因素及各种实验条件优化。研究结果表明：模板DNA的浓度适宜范围为20ng／反应-80ng／反应RAPD均可得到一致的结果;dNTVs的适宜浓度范围为200μmol／L-400μmol／L;Mg^2 适宜浓度范围为1．5mmol／L-2．0mmol／L;其合适的复性温度为35—37℃;2min的延伸时间,45次热循环。按照此优化的RAPD条件进行重复实验,实验结果重现性良好,因而确定了苦丁茶冬青RAPD反应体系之最佳的实验条件。     

FBXW7 suppresses epithelial‐mesenchymal transition and chemo‐resistance of non‐small‐cell lung cancer cells by targeting snai1 for ubiquitin‐dependent degradation

Objectives

FBXW7 acts as a tumour suppressor by targeting at various oncoproteins for ubiquitin‐mediated degradation. However, the clinical significance and the involving regulatory mechanisms of FBXW7 manipulation of NSCLC regeneration and therapy response are not clear.

Materials and Methods

Immunohistochemical staining and qRT‐PCR were applied to detect FBXW7 and Snai1 expression in 100 samples of NSCLC and matched tumour‐adjacent tissues. FBXW7 manipulation of cancer biological functions were studied by using MTT assay, immunoblotting, flow cytometry, transwells, wound healing assay, and sphere‐formation assays. Immunofluorescence and co‐immunoprecipitation were used to analyse the possible interaction between Snai1 and FBXW7.

Results

We detected the decreased FBXW7 expression in majority of the NSCLC tissues, and lower FBXW7 level was correlated with advanced TNM stage. Furthermore, those patients with decreased FBXW7 expression tend to have both poorer 5‐year survival outcomes, and shorter disease‐free survival, comparing to those with higher FBXW7 levels. Functionally, we found that FBXW7 enforcement suppressed NSCLC progression by inducing cell growth arrest, increasing chemo‐sensitivity and inhibiting Epithelial‐mesenchymal Transition (EMT) progress. Results further showed that FBXW7 could interact with Snai1 directly to degrade its expression through ubiquitylating alternation in NSCLC, which could be partially abrogated by restoring Snai1 expression.

Conclusions

FBXW7 conduction of tumour suppression was partly through degrading Snai1 directly for ubiquitylating regulation in NSCLC

     

Crystal structures of Nipah and Hendra virus fusion core proteins

The Nipah and Hendra viruses are highly pathogenic paramyxoviruses that recently emerged from flying foxes to cause serious disease outbreaks in humans and livestock in Australia, Malaysia, Singapore and Bangladesh. Their unique genetic constitution, high virulence and wide host range set them apart from other paramyxoviruses. These characteristics have led to their classification into the new genus Henpavirus within the family Paramyxoviridae and to their designation as Biosafety Level 4 pathogens. The fusion protein, an enveloped glycoprotein essential for viral entry, belongs to the family of class I fusion proteins and is characterized by the presence of two heptad repeat (HR) regions, HR1 and HR2. These two regions associate to form a fusion-active hairpin conformation that juxtaposes the viral and cellular membranes to facilitate membrane fusion and enable subsequent viral entry. The Hendra and Nipah virus fusion core proteins were crystallized and their structures determined to 2.2 A resolution. The Nipah and Hendra fusion core structures are six-helix bundles with three HR2 helices packed against the hydrophobic grooves on the surface of a central coiled coil formed by three parallel HR1 helices in an oblique antiparallel manner. Because of the high level of conservation in core regions, it is proposed that the Nipah and Hendra virus fusion cores can provide a model for membrane fusion in all paramyxoviruses. The relatively deep grooves on the surface of the central coiled coil represent a good target site for drug discovery strategies aimed at inhibiting viral entry by blocking hairpin formation.     

Fluorescent labeling for clonal selection of Marc 145 cells secreting high levels of recombinant protein PBD-1

Despite the powerful impact gene expression markers like the green fluorescent protein (GFP) or enhanced GFP (EGFP) exert on linking the expression of recombinant protein for selection of high producers in recent years, there is still a strong incentive to develop more economical and efficient methods for isolating mammalian cell clones secreting high levels of recombinant proteins. Here we present a new method based on the co-expression of EGFP that allows clonal selection in standard 96-well cell culture plates. The genes encoding the EGFP protein and the related protein are linked by an internal ribosome entry site and thus are transcribed into the same mRNA in an independent translation process. Since both proteins arise from a common mRNA, the EGFP expression level correlates with the expression level of the therapeutic protein in each clone. By expressing recombinant porcine β-defensin 1 in Marc 145 cells, we demonstrate the robustness and performance of this technique. The method can be served as an alternative to identify high-producer clones with various cell sorting methods.