Genetic characterization of H7N2 influenza virus isolated from pigs

Because pigs have respiratory epitheliums which express both α2-3 and α2-6 linked sialic acid as receptors to influenza A viruses, they are regarded as mixing vessel for the generation of pandemic influenza viruses through genetic reassortment. A H7N2 influenza virus (A/swine/KU/16/2001) was isolated from pig lungs collected from the slaughterhouse. All eight genes of the influenza virus were sequenced and phylogenetic analysis indicated that A/swine/KU/16/2001 originated in Hong Kong and genetic reassortment had occurred between the avian H7N2 and H5N3 influenza viruses. The first isolation of H7 influenza virus in pigs provides the opportunity for genetic reassortment of influenza viruses with pandemic potential and emphasizes the importance of surveillance for atypical swine influenza viruses.     

Peptidomimetics in the discovery of new insect growth regulators: studies on the structure-activity relationships of the core pentapeptide region of allatostatins

Cockroach-type allatostatins (ASTs) were discovered in cockroaches through their capacity to inhibit the production of juvenile hormone by the corpora allata (CA). ASTs were considered as potential insect growth regulator (IGR) candidates, but several disadvantages, including the absence of the effect in vivo and rapid degradation in vivo, precluded their application in pest management. The CA were selected as the target, and the core pentapeptide region (YDFGL) was chosen as the lead sequence in the search for new IGRs based on the allatostatins. We designed and synthesized 24 analogues, which mimicked each amino acid of the core region, to determine structure-activity relationships and the possibility of shortening the ASTs in the core region while retaining activity. The results suggest that the sequence FGLa is more important than Y/FX because Y/FX mimics show strong effects in vitro and in vivo. In particular, compound I3 was synthesized by substitution of Y/FX with 6-phenylhexnoic acid and exhibits higher activity in vitro than the complete core region. Furthermore, compound I3 has a clear effect in vivo on juvenile hormone (JH) biosynthesis of Diploptera punctata females, providing a possible application for cockroach management. On the basis of the structure-activity relationship of pentapeptide analogues, a general structure of potential potent AST analogues is proposed here. A new approach using peptidomimetics in the discovery of IGRs is demonstrated in our study.     

Epoxygenated fatty acids and soluble epoxide hydrolase inhibition: novel mediators of pain reduction

The soluble epoxide hydrolase (sEH) enzyme was discovered while investigating the metabolism of xenobiotic compounds in the Casida laboratory. However, an endogenous role of sEH is to regulate the levels of a group of potent bioactive lipids, epoxygenated fatty acids (EFAs), that have pleiotropic biological activities. The EFAs, in particular the arachidonic acid derived epoxy eicosatrienoic acids (EETs), are established autocrine and paracrine messengers. The most recently discovered outcome of inhibition of sEH and increased EFAs is their effects on the sensory system and in particular their ability to reduce pain. The inhibitors of sEH block both inflammatory and neuropathic pain. Elevation of EFAs, in both the central and peripheral nervous systems, blocks pain. Several laboratories have now published a number of potential mechanisms of action for the pain-reducing effects of EFAs. This paper provides a brief history of the discovery of the sEH enzyme and argues that inhibitors of sEH through several independent mechanisms display pain-reducing effects.     

犬单纯性脾扭转的超声诊断

脾脏扭转是指脾脏沿胃脾韧带发生扭转,致使脾脏血液循环发生阻塞,导致脾脏出现血栓、淤血、出血及坏死。脾脏扭转最常发生于大型的深胸犬,多继发于胃扩张扭转,也可单独发生。单纯性脾脏     

Minimum anesthetic concentration and cardiovascular dose-response relationship of isoflurane in cinereous vultures (Aegypius monachus)

This study aimed to determine the minimum anesthetic concentration (MAC) and dose-related cardiovascular effects of isoflurane during controlled ventilation in cinereous vultures (Aegypius monachus). The MAC was determined for 10 cinereous vultures as the midpoint between the end-tidal isoflurane concentration that allows gross purposeful movement and that which prevents the movement in response to clamping a pedal digit. Immediately after the MAC was determined, the cardiovascular effects of isoflurane at 1.0, 1.5, and 2.0 times the MAC were investigated in seven of the 10 birds. The MAC of isoflurane for 10 cinereous vultures during controlled ventilation was 1.06 +/- 0.07% (mean +/- SD). When the isoflurane concentration was increased to 1.5 and 2.0 times the MAC, there was significant dose-dependent decrease in the arterial blood pressure. However, the heart rate did not change over a range of 1.0 to 2.0 times the MAC.     

Necrotic enteritis in collared (Pecari tajacu) and white-lipped (Tayassu pecari) peccaries

An outbreak of necrotic enteritis caused by Clostridium perfringens type C was diagnosed in captive collared (Pecari tajacu) and white-lipped (Tayassu pecari) peccaries housed in the Laboratory of Applied Ethology of Universidade Estadual de Santa Cruz located in Ilhéus, State of Bahia, Brazil. Four collared peccaries and three white-lipped peccaries, all juveniles (25-105 days old), were affected. For all affected animals, lethargy and inappetance were followed by sudden death within 24 hours. Histopathology of intestinal wall, culture of C. perfringens type C, and the identification of beta-toxin from intestinal content confirmed the diagnosis.     

地膜覆盖对夏玉米生理指标及环境

利用夏玉米地膜覆盖和露地环境因子和生理指标试验结果对比,得出地膜覆盖改变了土壤水循环系统,增加了浅层土壤温度,促进土壤水分运移,抑制棵间蒸发,使得表层土壤在长期无降水的情况下能保持较高的含水量;覆膜区夏玉米单株叶面积生理指标较露地情况明显增加。     

杂交玉米制种田带叶去雄法的应用

为了保证杂交玉米制种田母本自交系的天花能及时、彻底、干净地去掉,使用带叶去雄法是非常必要的.     

脱粒机的安装和使用

1.脱粒机应平稳地安装在一个厚薄一致的木架上,并用螺钉固定牢靠。电钮开关要接到便于操作的地方,要安全、防触电;用柴油机作动力,柴油机也要固定牢靠,使两个皮带轮中心距保持在1.5～2m的距离。     

葡萄种质资源鉴评研究进展

葡萄种质资源的鉴别和评价是葡萄育种中必不可少的环节,该论文简要介绍了葡萄种质资源的分类,系统综述了葡萄种质资源的分子鉴定、形态特征、生物学特征、品质特征、抗寒性和抗病性的评价项目和相关方法,并重点分析了葡萄种质资源果实的酚类含量及其抗氧化活性的评价方法,以期为今后葡萄种质资源的鉴评工作提供参考.