鱼类对饲料可消化糖的利用和代谢特征

糖类是鱼类三大营养物质之一,可消化糖作为一种性价比较高的能量物质,其合理利用对饲料成本的降低和饲料物理性状的维持具有重要意义,但鱼类对糖的利用有限,投喂含有一定比例可消化糖的膨化商业饲料易引起肝脏疾病的发生。文章总结了部分已发表关于鱼类糖耐受和生长试验结果的报道,发现不同鱼类对葡萄糖的代谢模式存在一定的差异,一些鱼类倾向于将过量葡萄糖以糖原的形式储存在肝脏中,而有些鱼类则既能合成糖原也能合成脂肪。糖耐量试验是了解鱼类利用可消化糖类的重要研究手段,但目前还没有统一的标准,导致研究结果的参考意义不强。作者建议将来在统一方法标准的基础上,重点研究不同鱼类的葡萄糖代谢特征以及调控方法。     

Steroid control of longevity in Drosophila melanogaster

Ecdysone, the major steroid hormone of Drosophila melanogaster, is known for its role in development and reproduction. Flies that are heterozygous for mutations of the ecdysone receptor exhibit increases in life-span and resistance to various stresses, with no apparent deficit in fertility or activity. A mutant involved in the biosynthesis of ecdysone displays similar effects, which are suppressed by feeding ecdysone to the flies. These observations demonstrate the importance of the ecdysone hormonal pathway, a new player in regulating longevity.     

Suppression of HIV infection in AZT-treated SCID-hu mice

The SCID-hu mouse, engrafted with human hematolymphoid organs, is permissive for infection with the human immunodeficiency virus (HIV). This mouse model was used to test compounds for antiviral efficacy. Two weeks after infection with HIV, 100 percent (40/40) of SCID-hu mice were positive for HIV by the polymerase chain reaction. When first treated with 3'-azido-3'-deoxythymidine (AZT), none (0/17) were HIV-positive by this assay. However, AZT-treated SCID-hu mice did have a few infected cells; after AZT treatment was stopped, viral spread was detected by polymerase chain reaction in such mice. Thus, the SCID-hu mouse provides a means to directly compare new antiviral compounds with AZT and to further improve antiviral efficacy.     

Chlorella 11-Peptide Inhibits the Production of Macrophage-Induced Adhesion Molecules and Reduces Endothelin-1 Expression and Endothelial Permeability

The inflammation process in large vessels involves the up-regulation of vascular adhesion molecules such as endothelial cell selectin (E-selectin), intercellular cell adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) which are also known as the markers of atherosclerosis. We have reported that Chlorella 11-peptide exhibited effective anti-inflammatory effects. This peptide with an amino sequence Val-Glu-Cys-Tyr-Gly-Pro-Asn-Arg-Pro-Gln-Phe was further examined for its potential in preventing atherosclerosis in this study. In particular, the roles of Chlorella 11-peptide in lowering the production of vascular adhesion molecules, monocyte chemoattractant protein (MCP-1) and expression of endothelin-1 (ET-1) from endothelia (SVEC4-10 cells) were studied. The production of E-selectin, ICAM-1, VCAM-1 and MCP-1 in SVEC4-10 cells was measured with ELISA. The mRNA expression of ET-1 was analyzed by RT-PCR and agarose gel. Results showed that Chlorella 11-peptide significantly suppressed the levels of E-selectin, ICAM, VCAM, MCP-1 as well as ET-1 gene expression. The inhibition of ICAM-1 and VCAM-1 production by Chlorella 11-peptide was reversed in the presence of protein kinase A inhibitor (H89) which suggests that the cAMP pathway was involved in the inhibitory cause of the peptide. In addition, this peptide was shown to reduce the extent of increased intercellular permeability induced by combination of 50% of lipopolysaccharide (LPS)-activated RAW 264.7 cells medium and 50% normal SEVC cell culture medium (referred to as 50% RAW-conditioned medium). These data demonstrate that Chlorella 11-peptide is a promising biomolecule in preventing chronic inflammatory-related vascular diseases.     

Cardiopulmonary effects of a new inspiratory impedance threshold device in anesthetized hypotensive dogs

ObjectiveTo compare the hemodynamic and respiratory effects of an inspiratory impedance threshold device (ITD) in anesthetized normotensive and hypotensive dogs.Study designProspective randomized study.AnimalsTen adult dogs.MethodsDogs were anesthetized with propofol followed by isoflurane. During spontaneous ventilation, tidal volume ( $\dot{\mathrm{V}}$), systolic (SAP), mean (MAP) and diastolic arterial blood pressure, central venous pressure, gastric PCO₂ as an indicator of gastric perfusion, subcutaneous oxygen tension, subcutaneous blood flow, cardiac index (CI), systemic vascular resistance and blood lactate were monitored. To monitor respiratory compliance (RC) and resistance (ResR), animals were briefly placed on mechanical ventilation. Dogs were studied under four different conditions: 1) normotension (MAP > 60 mmHg) with and without the ITD and 2) hypotension (target MAP = 40 mmHg) with and without ITD. These four conditions were performed during one anesthetic period, allowing for stabilization of parameters for each condition. Data were analyzed by anova repeated measure mixed models.ResultsNo cardiovascular changes were detected between no ITD and ITD in the normotensive state. During hypotension, CI was higher with the ITD (5 ± 1.0 L minute^?1 m^?2) compared with no ITD (4 ± 1.3 L minute^?1 m^?2). During hypotension, SAP was increased with ITD (80 ± 14 mmHg) versus without ITD (67 ± 13 mmHg). There was an increase in ResR and decreased RC with the ITD in both normotensive and hypotensive state.Conclusion and clinical relevanceImpedance threshold device in dogs during isoflurane-induced hypotension improved CI and SAP but had negative effects on RC and ResR.     

斑石鲷irf3基因鉴定及其在虹彩病毒感染下的表达模式分析

干扰素调节因子（irf3）是干扰素调节因子（IRF）家族的一员,是I型干扰素依赖性免疫反应的主要转录调节因子,在针对DNA和RNA病毒的先天免疫反应中发挥重要作用。本研究中,斑石鲷irf3基因（Oplegnathus punctatus interferon regulatory factors 3,Opirf3）来自实验室斑石鲷基因组数据库,经分析鉴定Opirf3的CDS序列全长1362 bp,可编码453个氨基酸,预测其蛋白分子量为50.0 kDa,理论等电点为4.97,有一个IRF结构域和一个IRF-3结构域。荧光定量分析显示,Opirf3在斑石鲷肝脏、鳃、心脏、皮肤、脾脏、肠、脑、肾、胃和头肾组织均有表达;虹彩病毒感染7 d时,免疫组织肝、脾和肾脏中Opirf3的表达水平显著上调。斑石鲷肾细胞系体外刺激实验显示,不同浓度poly I:C刺激后,Opirf3的表达量较对照组均显著升高,poly I:C浓度为100 μg/mL时,肾细胞中Opirf3的相对表达水平升高,为对照组的86.8倍。siRNA干扰后,斑石鲷肾细胞系中Opirf3表达水平显著下调30%,下游基因IFN-α、CD40、CD80和IL-1β显著下调,IL-6显著上调。以上结果可能表明Opirf3基因参与了I型IFN在斑石鲷抗虹彩病毒过程中的先天免疫反应。本研究可为斑石鲷抗病分子育种提供理论依据。     

Social structure in a critically endangered Indo‐Pacific humpback dolphin (Sousa chinensis) population

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Agronomic,molecular and antioxidative characterization of red- and purple-pericarp rice (Oryza sativa L.) mutants in Taiwan

Pigmentation of rice grain is controlled by Ra, Rc and Rd genes, and the expressions of these genes differ among red-, purple- and white-pericarp varieties. The present study examined the grain yield and the expression of Ra, Rc and Rd genes in non-waxy white-pericarp rice SA418 and waxy white-pericarp rice SA419 and their respective red-pericarp and purple-pericarp mutants with waxy or non-waxy endosperm. Significant variations in 100-grains weight and grain yield were observed among the tested mutants. The Ra was expressed in purple-pericarp mutants, while the Rc was expressed in red-pericarp mutants. The total phenolics, total flavonoids, total anthocyanins and total proanthocyanidins contents and antioxidant activities in the bran part also differed among the mutants. Non-waxy red-pericarp mutant M-69 had heavier 100-grains weight (2.86 g), contained more total phenolics (49.37 mg g⁻¹ bran dry weight) and produced higher grain yield (6.93 t ha⁻¹) than white-pericarp rices SA418 (2.43 g, 2.89 mg g⁻¹ bran dry weight and 2.80 t ha⁻¹, respectively) and SA419 (2.62 g, 2.20 mg g⁻¹ bran dry weight and 6.73 t ha⁻¹, respectively). Thus, the polished rice grain of M-69 can be used for staple food consumption, and its bran parts are useful for producing health-promoting by-product.