Plasma levels of vitamin D3 metabolites during parr-smolt transformation of Atlantic salmon Salmo salar L.

Plasma vitamin D and vitamin D metabolites were measured in Atlantic salmon parr during smoltification and after transfer to seawater. The fish were fed commercial feed for 5 months under natural light, and Na⁺/K⁺ ATPase was measured as an indicator of the smoltification status. No significant differences were recorded in the level of plasma vitamin D metabolites. However, a tendency of increasing plasma concentration of 25OHD₃ and also a temporary increase in plasma 1,25(OH)₂D₃ and 24,25(OH)₂D₃ were recorded prior to seawater transfer. The minor changes in plasma levels of the metabolites indicate a role of the vitamin D metabolites during parr–smolt transformation, although we do not know whether the increased levels are caused by increased synthesis of the metabolites or by decreased binding to receptors or decreased excretion.     

Synthesis and Evaluation of Some New Aza-B-homocholestane Derivatives as Anticancer Agents

Using analogues of some marine steroidal oximes as precursors, a series of aza-B-homocholestane derivatives possessing different substituted groups at the 3-position of the steroidal nucleus were synthesized. Their biological activity against cancer cell proliferation was determined with multiple cancer cell lines. Aza-B-homocholestane derivatives possessing 3-hydroxyl, 3-hydroximino and 3-thiosemicarbazone groups displayed remarkable cytotoxicity to cancer cells via apoptosis inducing mechanism. Compounds 5, 10, 12, 15 and 18 exhibited better potency to inhibit cancer cell proliferation. In addition, compound 15 was further evaluated with three dimensional (3D) multicellular spheroids assay to determine its potency against spheroid growth. The structure-activity relationship (SAR) generated in the studies is valuable for the design of novel chemotherapeutic agents.     

Numerosol A–D,New Cembranoid Diterpenes from the Soft Coral Sinularia numerosa

Four new cembrane-type diterpenes; numerosol A–D (1–4); along with a known steroid; gibberoketosterol (5); were isolated from the Taiwanese soft coral Sinularia numerosa. The structures of these metabolites were determined by extensive analysis of spectroscopic data. Gibberoketosterol (5) exhibited cytotoxicity against P-388 (mouse lymphocytic leukemia) cell line with an ED₅₀ of 6.9 μM.     

Resolvin D1, a Metabolite of Omega-3 Polyunsaturated Fatty Acid,Decreases Post-Myocardial Infarct Depression

We hypothesized that inflammation induced by myocardial ischemia plays a central role in depression-like behavior after myocardial infarction (MI). Several experimental approaches that reduce inflammation also result in attenuation of depressive symptoms. We have demonstrated that Resolvin D1 (RvD1), a metabolite of omega-3 polyunsaturated fatty acids (PUFA) derived from docosahexaenoic acid, diminishes infarct size and neutrophil accumulation in the ischemic myocardium. The aim of this study is to determine if a single RvD1 injection could alleviate depressive symptoms in a rat model of MI. MI was induced in rats by occlusion of the left anterior descending coronary artery for 40 min. Five minutes before ischemia or after reperfusion, 0.1 μg of RvD1 or vehicle was injected in the left ventricle cavity. Fourteen days after MI, behavioral tests (forced swim test and socialization) were conducted to evaluate depression-like symptoms. RvD1 reduced infarct size in the treated vs. the vehicle group. Animals receiving RvD1 also showed better performance in the forced swim and social interaction tests vs. vehicle controls. These results indicate that a single RvD1 dose, given 5 min before occlusion or 5 min after the onset of reperfusion, decreases infarct size and attenuates depression-like symptoms.     

基于Kinect V3的单株作物自动化三维重建与验证

为高效、精确地对单株作物进行三维重建,以点云方式无损测量作物表型信息,该研究提出一种基于Kinect V3深度相机的三维重建系统。使用步进电机搭建了一个旋转台,并将旋转台面设计成多颜色同心圆,利用同心圆计算平面法向量及圆心两特征信息,用于点云水平校准以及获取点云间的旋转平移矩阵;将Kinect V3采集的多视角点云变换到同一坐标系下,并结合裁剪迭代最近点（Trimmed Iterative Closest Point,TrICP）算法实现了多视角点云的粗配准与精配准,完成了作物三维重建。为检验该研究的三维重建效果,选取菜心、黄瓜苗为试验对象,与多视图立体视觉-运动恢复结构（Multi-View Stereo and Structure From Motion,MVS-SFM）算法重建点云进行对比,并提取叶面积参数与人工测量值进行比较。结果表明,两种方法下重建后的菜心点云间平均距离误差为0.59 cm,黄瓜苗点云间平均距离误差为0.67 cm,具有较高的相似度,而相较于MVS-SFM算法,该研究提出的方法的重建速度提高了约90%;该研究提出的方法所重建点云,菜心叶面积提取与标准参考值相对误差均值为5.88%,均方根误差为3.83 cm2,黄瓜苗叶面积提取与标准参考值相对误差均值别为6.50%,均方根误差为2.08 cm2,都显现出较高的准确性。该研究提出的方法能对单株作物进行快速三维重建,能有效提取叶面积参数,可为作物育种、栽培和农业生产提供高效技术手段和数据支持。     

铁皮石斛枫斗加工前后差异成分比较

铁皮石斛(Dendrobium officinale Kimura et Migo)的传统功效为益胃生津、滋阴清热,在降血糖方面具有较好的作用。前期研究发现,与铁皮石斛鲜条相比,枫斗的α-葡萄糖苷酶抑制率更高,且枫斗中化学成分种类丰富。为明确铁皮石斛枫斗与鲜条的差异性成分,阐明铁皮石斛加工成枫斗的科学内涵,本研究利用超高效液相色谱-四级杆串联飞行时间质谱仪(UPLC-QTOF-MS)在正离子模式下采集二者的代谢物信息,通过主成分分析、偏最小二乘判别分析等算法挖掘差异性化合物,并利用质谱碎片、数据库比对等方式鉴定差异性成分,最后采用聚类分析方法研究差异性成分在铁皮石斛枫斗和鲜条中的含量变化规律。经过筛选和鉴定共得到16种差异性化合物,其中柚皮素、4,4'-二羟基-3,5-二甲基联苄、诺比林A、石斛酚等12种黄酮、联苄类化合物在枫斗中含量较高,而α-亚麻酸、L-苯丙氨酸、草质素等4种脂肪酸、氨基酸类化合物在鲜条中含量较高,这些差异性成分可能是潜在的铁皮石斛枫斗降血糖功能成分。本研究结果为阐明铁皮石斛枫斗降血糖物质基础提供了数据支撑,对进一步促进铁皮石斛精深加工具有重要意义。     

慢病毒生产卵泡抑素转基因绵阳PCR检测方法的建立(英文)

[目的]建立稳定快速的慢病毒转基因羊DNA水平检测方法。[方法]采集初生转基因羔羊的子叶、脐带、尾组织以及死亡羔羊的全身各组织,提取基因组DNA作为模板进行PCR检测,以Follistatin基因N+D1片段特异性引物进行PCR检测;同时,对慢病毒载体的CMV启动子、5’-LTR等结构元件进行PCR检测;提取死亡羔羊的全身组织以及转基因羔羊的活体肌肉组织总RNA,进行RTPCR检测。[结果]采用试剂盒提取的基因组DNA比常规方法提取的DNA快速、高效,且更易被检测,扩增时的引物采用载体上游与目标基因下游的组合大大增加了检测的特异性,避免了内源性目标基因的干扰而造成假阳性;初生转基因羔羊的尾组织可作为PCR检测的组织样品,其结果可靠、准确;对CMV启动子及5’-LTR等结构元件作PCR检测为转基因动物的安全性考察提供了数据,同时验证了转基因羔羊目的基因的检测结果;对转基因羔羊肌肉组织提取总RNA后进行RT-PCR检测,其中有3只羔羊没有检测到转录产物,其他均有转录。[结论]该研究建立的转基因绵羊PCR检测方法高效、快速且准确,为进一步蛋白水平检测提供试验依据,也为建立转基因绵羊系统性多层次的检测方法奠定基础,还为转基因绵羊的安全监测提供了稳定的技术平台。     

D型产气荚膜梭菌ε毒素蛋白结构及抗原表位分析

利用生物软件对D型产气荚膜梭菌ε毒素的蛋白结构、抗原表位进行预测与分析。综合ε毒素蛋白亲水性、表面可能性、抗原指数、二级结构预测结果显示,肽链13-19、44-47、59-63、79-82、94-97、151-153、200-204、211-221、245-250、257-260位可能存在B细胞抗原表位,三级结构预测的94、151结合位点位于94-97、151-153抗原表位区内。     

梓树露地与大棚播种育苗效果比较

为比较梓树露地播种育苗与大棚播种育苗的育苗效果,研究了不同播种方式对梓树播种后种子破土时间、出苗时间、出苗率以及梓树植株性状的影响。结果表明:与露地播种育苗相比,大棚播种育苗出苗时间可提前20d左右,出苗率高出7%,幼苗植株高度高出57.2%,基茎高出35.7%,叶片数高出75.8%,而且大棚内梓树幼苗叶片较大。     

维生素D对家禽的营养研究进展

维生素D(VD)是一种脂溶性维生素,是动物体内不可缺少的,其在促进骨骼发育和钙磷吸收、改善动物肉品质及免疫细胞的形成等方面都起到重要的作用,虽然VD在动物体内可以合成,但其需要量较大,仍需要从食物中获得,饲料中添加的VD量过多或过少都会影响动物的生产性能、钙和磷的代谢和骨代谢等。因此,适宜的VD添加量具有重要的生物学意义。文章综述了家禽VD的需要量、影响因素及其生理功能。