昆虫弦音器及其声音感受分子机制

弦音器是昆虫类特有的一种机械感受器,亦称弦音感受器或剑梢感受器。它主要具有感知外界声压和体内肌肉运动的听觉功能,研究弦音器的机能结构对揭秘昆虫听觉的神经机制有重要的科学意义。本文从弦音器多样性和进化入手,重点综述了弦音器的微细结构、基因功能定位、声音感受分子机制及其声压增幅分子生物物理学原理,为昆虫听觉仿生学的研究提供了理论依据。     

鸡PPARγ基因的表达特性及其对脂肪细胞增殖分化的影响

为分析鸡PPARγ基因的组织表达特性及其在脂肪细胞增殖和分化过程中的功能,文章以东北农业大学高、低腹脂双向选择品系肉鸡为实验材料,利用Western blotting方法,检测PPARγ基因的组织表达特性及其在高、低脂系肉鸡腹部脂肪组织间的表达差异;采用RNAi技术,在鸡原代脂肪细胞中抑制PPARγ基因的表达后,通过MTT和油红O提取比色的方法,研究鸡PPARγ基因对脂肪细胞增殖和分化的调控作用;利用Real-timePCR和Western blotting技术,分析PPARγ基因表达下调后,其他脂肪细胞分化转录因子以及与脂肪细胞分化相关的重要基因的表达变化情况。结果表明,PPARγ基因在7周龄高脂系肉鸡腹部脂肪组织、肌胃、脾脏、肾脏组织中表达量较高,在心脏中表达量较低,在肝脏、胸肌、腿肌、十二指肠中未检测到表达信号;与高脂系相比,PPARγ基因在5和7周龄低脂系肉鸡腹部脂肪组织中的表达量较低(P<0.05);PPARγ基因的表达量下降后,鸡脂肪细胞的增殖能力增强,分化能力减弱;同时,C/EBPα、SREBP1、A-FABP、Perilipin1、LPL、IGFBP-2基因的表达量均下降(P<0.05)。由此可见,PPARγ基因的表达可能与肉鸡腹部脂肪的沉积有一定的关系,该基因可能是调控鸡脂肪细胞增殖与分化的关键因子。     

紫毛香茶菜中的黄酮类化合物

从紫毛香茶菜（Isodon enanderianus)的茎叶提取物中分离到7个黄酮类化合物,经波谱分析鉴定,其中一个为新的黄酮甙,即5-羟基-6,7,4-三甲氧基黄酮-8-O-β-D-葡萄糖甙（1）;其它6个已知的黄酮类化合物分别为芫花素（genkwanin,2)、滨蓟素（cirsimar-tin,3)、胡麻素（pedalitin,4)、鼬瓣花亭（ladanetin,5)、isothymusin-8-O-β-D-glucoside（6）和槲皮甙（quercitrin,7)。     

小黑麦抗真菌蛋白组分的分离纯化和性质研究

以木霉为指示菌,小黑麦中饲237种子中的蛋白提取物经过分离纯化后,得到了3种主要的抗真菌蛋白组分,经酶活检测鉴定,分别是分子量为30.5 kD的ClassⅡ型几丁质酶,两种分子量为51kD和23 kD的β-1,3-葡聚糖酶。其中几丁质酶的最适反应pH为6.0,最适反应温度为37℃,测定的N末端氨基酸序列与大麦几丁质酶的有很高的同源性。在一定条件下,这3种蛋白组分都有较强的抗木霉活性,并且有明显的协同作用,同时它们对离体易感小麦叶片上白粉菌有很好的生长抑制作用。     

苜蓿银纹夜蛾核多角体病毒iap1和iap2基因功能分析

苜蓿银纹夜蛾核多角体病毒（Autographa californica nucleopolyhedrovirus,AcMNPV）基因组含有3个细胞凋亡抑制基因,即p35,iap1和iap2.其中,p35作为一个有效的依赖于天冬氨酸的半胱氨酸蛋白酶（caspase）抑制因子,能够抑制多种因素诱发细胞凋亡,而iap1和iap2的功能仍未完全明晰,本研究对IAP1和IAP2的功能进行了详细分析.缺失了p35的AcMNPV仍可抑制棉铃虫核多角体病毒（Helicoverpa armigera single nucleocapsid NPV,HearNPV）诱导的BTI-Tn-5B1-4（Tn-Hi5）细胞凋亡并挽救HearNPV在Tn-Hi5细胞中复制及HearNPV出芽型病毒粒子的产生.进一步构建了瞬时表达质粒以及分别表达AcMNPV的p35,iap1和iap2基因的重组HearNPV,转染瞬时表达的IAP1和IAP2对HearNPV感染诱导的Tn-Hi5细胞凋亡有抑制效果,而重组病毒感染Tn-Hi5细胞也可抑制其凋亡并在其中复制,然而重组HearNPV表达的p35,iap1和iap2并未能挽救出芽型病毒粒子的产生.结果表明,AcMNPV的iap1和iap2基因表达产物作为细胞凋亡抑制因子是有功能的。     

高糖环境下Trx1过表达对HBZY-1细胞中MMP9表达的影响

硫氧还蛋白1（thioredoxin1,Trx1）是细胞内一种重要的巯基 二硫键氧化还原酶,在细胞内氧化还原状态的调控及抵抗氧化应激损伤过程中发挥重要的作用.为了探讨高糖环境下Trx1过表达对 肾小球系膜细胞（glomerular mesangial cells）HBZY-1中基质金属蛋白酶9(matrix metalloproteinase 9,MMP9)表达水平的影响,本实验采用脂质体介导的瞬时转染实现Trx1蛋白过表达;采用RT-PCR和明胶酶谱法检测HBZY-1中MMP9 mRNA及酶活性的变化;通过流式细胞仪检测细胞内活性氧的含量.实验结果显示,高糖状态下,细胞中MMP9的mRNA和酶活性分别在12 h、24 h、48 h时表达增加（P＜0.05）;HBZY-1细胞中转染正义Trx1组,MMP9 mRNA水平及MMP9酶活性,高糖组与正常糖组无明显差异（P＞0.05）,转染反义Trx1组和未转染组中,高糖组均比正常糖组表达增加,差异有统计学意义（P＜0.01）;细胞中活性氧含量,高糖作用12 h、24 h、48 h均较正常糖组明显增多（P＜0.01）,高糖环境下转染正义Trx1质粒较转染反义Trx1质粒,细胞中活性氧含量明显减少,差异有统计学意义（P＜0.05）.实验提示,高糖环境下,Trx1过表达对MMP9的抑制作用是通过减少细胞内活性氧含量来实现的.本实验为Trx1的抗氧化作用提供新的证据,也为继续探讨 Trx1在糖尿病肾病的预防和治疗提供新的思路.     

Androgen receptor coregulator ARA267-α interacts with death receptor-6 revealed by the yeast two-hybrid

ARA267-α is a newly identified androgen receptor coactivator. In order to further elucidate its precise role in cells, using the ARA267-α fragment containing four PHD and one SET conserved domains as bait we revealed an ARA267-α-PHD-SET-interacting protein, death receptor-6 (DR6), in the yeast two-hybrid screening. DR6 is the member of TNF receptor family and has a death domain in its intracellular cytoplasmic portion (DR6cp) to mediate the cell apoptosis. The interaction between ARA267-α-PHD-SET and DR6cp was confirmed in vitro and in vivo. Our finding implied that androgen signaling pathway might cross talk with apoptosis signaling pathway through the interaction between ARA267-α and DR6.     

A Dutch guideline for the treatment of scoliosis in neuromuscular disorders

Background

Children with neuromuscular disorders with a progressive muscle weakness such as Duchenne Muscular Dystrophy and Spinal Muscular Atrophy frequently develop a progressive scoliosis. A severe scoliosis compromises respiratory function and makes sitting more difficult. Spinal surgery is considered the primary treatment option for correcting severe scoliosis in neuromuscular disorders. Surgery in this population requires a multidisciplinary approach, careful planning, dedicated surgical procedures, and specialized after care.

Methods

The guideline is based on scientific evidence and expert opinions. A multidisciplinary working group representing experts from all relevant specialties performed the research. A literature search was conducted to collect scientific evidence in answer to specific questions posed by the working group. Literature was classified according to the level of evidence.

Results

For most aspects of the treatment scientific evidence is scarce and only low level cohort studies were found. Nevertheless, a high degree of consensus was reached about the management of patients with scoliosis in neuromuscular disorders. This was translated into a set of recommendations, which are now officially accepted as a general guideline in the Netherlands.

Conclusion

In order to optimize the treatment for scoliosis in neuromuscular disorders a Dutch guideline has been composed. This evidence-based, multidisciplinary guideline addresses conservative treatment, the preoperative, perioperative, and postoperative care of scoliosis in neuromuscular disorders.     

Male preponderance in early diagnosed type 2 diabetes is associated with the ARE insertion/deletion polymorphism in the <Emphasis Type="Italic">PPP1R3A</Emphasis> locus

Background  

The ARE insertion/deletion polymorphism of PPP1R3A has been associated with variation in glycaemic parameters and prevalence of diabetes. We have investigated its role in age of diagnosis, body weight and glycaemic control in 1,950 individuals with type 2 diabetes in Tayside, Scotland, and compared the ARE2 allele frequencies with 1,014 local schoolchildren.