水稻稻瘟病抗性基因的克隆、育种利用及稻瘟菌无毒基因研究进展

稻瘟病是世界上影响水稻(Oryza sativa)粮食生产的主要病害之一, 抗病基因的发掘与利用是抗病育种的基础和核心。随着寄主水稻和病原菌稻瘟病菌(Magnaporthe oryzae)基因组测序和基因注释的完成, 水稻和稻瘟病菌的互作体系成为研究植物与真菌互作的模式系统。该文对稻瘟病抗病基因的遗传、定位、克隆及育种利用进行概述, 并通过生物信息学分析方法, 探讨了水稻全基因组中NBS-LRR类抗病基因在水稻12条染色体上的分布情况, 同时对稻瘟病菌无毒基因的鉴定及无毒蛋白与抗病蛋白的互作进行初步分析。最后对稻瘟病抗病基因研究存在的问题进行分析并展望了未来的研究方向, 以期为水稻抗稻瘟病育种发展和抗病机制的深入理解提供参考。     

大黄酸通过巨噬细胞激活的串扰调控肠道炎症中氧化还原介导的Nlrp3炎症小体的激活

巨噬细胞浸润和激活是急性结肠炎的关键步骤。巨噬细胞中氧化还原介导的Nlrp3炎症小体激活在介导结肠炎症反应中起着关键作用。从大黄根茎中分离出的大黄酸具有较强的抗炎作用。然而,其在调节急性结肠炎症中的作用尚未得到研究。来自澳门大学的王一涛及其团队研究了大黄酸在急性肠道炎症期间的保护机制及其对巨噬细胞活化的调节。结果发现大黄酸通过Nlrp3炎症小体干扰其在巨噬细胞中的复合物组装,降低IL-1β的分泌。大黄酸还通过激活Nrf2-HO1-NQO1通路,抑制Nox2亚单位的表达和易位以调节氧化还原平衡。     

基于配体捕捞结合HR-ESI-Q-TOF-MS快速鉴定和分离蛇莓的神经氨酸酶抑制剂

流感是一种急性呼吸道疾病,由甲型、乙型和丙型等流感病毒引起。其中,甲型和乙型流感病毒可导致季节性流行甚至全球大流行。流感病毒神经氨酸酶(NA)是病毒复制、传播和发病机制中的关键酶,因而研发神经氨酸酶抑制剂(NAIs)是对抗流感感染的有效途径之一。在中国,许多用于清热解毒的中药单独使用或作为中药配方来治疗流感显示出良好的疗效,但如何从中药中快速分离出活性物质是一个难题。     

Symposium: ethical considerations in HIV preventive vaccine research: examining the 18 UNAIDS guidance points. The 18 UNAIDS guidance points

Here are the 18 guidance points contained in the UNAIDS document on Ethical Considerations in HIV Preventive Vaccine Research, reproduced by kind permission of the Joint United Nations Programme on HIV/AIDS (UNAIDS).     

Comparison and validation of novel pyrogen tests based on the human fever reaction

The Limulus amoebocyte lysate (LAL) test has replaced about 80% of the use of the rabbit pyrogen test. Ideally, human-based in vitro tests are needed, to replace the remaining use of the rabbit test and the use of the LAL test. The progress of an EU-funded project is described, in which a number of in vitro tests, based on the human fever reaction are passing through a prevalidation study on the way to evaluation in a formal validation study.     

Effects of cod liver oil on tissue antioxidant pathways in normal and streptozotocin-diabetic rats

Lipid disorders and increased oxidative stress may exacerbate some complications of diabetes mellitus. Previous studies have implicated the beneficial effects of some antioxidants, omega-3 polyunsaturated fatty acids (PUFAs), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in the protection of cells from the destructive effect of increased lipids and lipid peroxidation products. This study, therefore, was designed to investigate the effects of cod liver oil (CLO, Lysi Ltd. Island), which comprises mainly vitamin A, PUFAs, EPA and DHA. Effects were monitored on plasma lipids, lipid peroxidation products (MDA) and the activities of antioxidant enzymes, glutathione peroxidase (GSHPx) and catalase in heart, liver, kidney and lung of non-diabetic control and streptozotocin (STZ)-induced-diabetic rats. Two days after STZ-injection (55 mg kg(-1) i.p.), non-diabetic control and diabetic rats were divided randomly into two groups as untreated or treated with CLO (0.5 ml kg(-1) rat per day) for 12 weeks. Plasma glucose, triacylglycerol and cholesterol concentrations were significantly elevated in 12-week untreated-diabetic animals; CLO treatment almost completely prevented these abnormalities in triacylglycerol and cholesterol, but hyperglycaemia was partially controlled. CLO also provided better weight gain in diabetic animals. In untreated diabetic rats, MDA markedly increased in aorta, heart and liver but was not significantly changed in kidney and lung. This was accompanied by a significant increase in both GSHPx and catalase enzyme activities in aorta, heart, and liver of diabetic rats. In kidney and lung, diabetes resulted in reduced catalase while GSHPx was significantly activated. In aorta, heart, and liver, diabetes-induced changes in MDA were entirely prevented by CLO treatment. In the tissues of CLO-treated diabetic animals, GSHPx activity paralleled those of control animals. CLO treatment also caused significant improvements in catalase activities in every tissue of diabetic rats, but failed to affect MDA and antioxidant activity in control animals. The current study suggests that the treatment of diabetic rats with CLO provides better control of glucose and lipid metabolism, allows recovery of normal growth rate, prevents oxidative/peroxidative stress and ameliorates endogenous antioxidant enzyme activities in various tissues. Because CLO contains a plethora of beneficial compounds together, its use for the management of diabetes-induced complications may provide important advantages.     

Mutation analysis of the coding sequence of the MECP2 gene in infantile autism

Mutations in the coding region of the methyl-CpG-binding protein 2 ( MECP2) gene cause Rett syndrome and have also been reported in a number of X-linked mental retardation syndromes. Furthermore, such mutations have recently been described in a few autistic patients. In this study, a large sample of individuals with autism was screened in order to elucidate systematically whether specific mutations in MECP2 play a role in autism. The mutation analysis of the coding sequence of the gene was performed by denaturing high-pressure liquid chromatography and direct sequencing. Taken together, 14 sequence variants were identified in 152 autistic patients from 134 German families and 50 unrelated patients from the International Molecular Genetic Study of Autism Consortium affected relative-pair sample. Eleven of these variants were excluded for having an aetiological role as they were either silent mutations, did not cosegregate with autism in the pedigrees of the patients or represented known polymorphisms. The relevance of the three remaining mutations towards the aetiology of autism could not be ruled out, although they were not localised within functional domains of MeCP2 and may be rare polymorphisms. Taking into account the large size of our sample, we conclude that mutations in the coding region of MECP2 do not play a major role in autism susceptibility. Therefore, infantile autism and Rett syndrome probably represent two distinct entities at the molecular genetic level.