马铃薯地上部绿色组织中糖苷生物碱合成调控的研究

为提高马铃薯品种(系)地上部分糖苷生物碱(SGAs)的含量,增强其抗逆性并改良块茎的品质。克隆了马铃薯茄啶鼠李糖基转移酶基因(sgt3)cDNA和1,5–二磷酸核酮糖羧化酶小亚基基因启动子(rbcS P);对sgt3亚细胞定位预测显示,该蛋白不具有叶绿体转运肽、线粒体导肽和分泌信号肽序列,推测可能位于细胞质;将克隆的sgt3 cDNA片段及rbcS重组到pCEPSP载体上,构建了具有草甘膦抗性标记的绿色组织特异表达sgt3基因植物表达载体。通过农杆菌介导法对马铃薯品种‘陇薯3号’和‘夏波蒂’进行转化,共获得了12株抗草甘膦的阳性转基因植株。对转基因植株的目的基因表达水平和SGAs含量分析发现,地上部sgt3基因相对表达量较未转化植株提高1.3~3.0倍,SGAs含量增加20%~37%,而转基因植株的块茎中SGAs含量变化不显著。本研究的结果为进一步培育枝、叶中高SGAs而块茎中低SGAs的马铃薯抗性品种提供了理论依据。     

Development of a lameness model in sheep for assessing efficacy of analgesics

Objective To develop a lameness model to assess the efficacy of analgesics for alleviating pain, swelling and systemic signs of inflammation in sheep. Procedures The response to subcutaneous injection of 0.1 or 0.2 mL turpentine in a forelimb pastern (n = 4 ewes per dose) was examined at 0, 3, 6, 24, 48 and 72 h. In a second experiment, responses were measured at 0, 2, 4, 6, 8, 10, 12 and 24 h in ewes receiving 0.1 mL turpentine ± meloxicam 1 mg/kg IV at 0 h (n = 6 per group). Responses measured included forceplate pressure, skin temperature, limb circumference, nociception, leucocyte count, neutrophil : lymphocyte ratio, haptoglobin and daily feed intake. Results Turpentine injection caused a decrease in weight borne on the treated limb, increased skin temperature, increased sensitivity at the injection site and leucocytosis by 2 h and increased limb circumference by 4 h. Weight borne and sensitivity of the injected limb returned to control levels after around 24 h, whereas tissue swelling, elevated skin temperature and elevated haptoglobin levels persisted for at least 72 h. Treatment with meloxicam improved weight borne by and tolerance to pressure exerted on the turpentine‐injected limb. Conclusions The local and systemic signs of inflammation and pain, temporary reduction in function of the affected limb and partial amelioration of some of these changes by the dose of meloxicam used here suggest that injection of turpentine in the lower forelimb provides a suitable model for examining the efficacy of analgesics for alleviation of pain and inflammation in sheep.     

菝葜属植物化学成分研究进展

概述了近几十年来菝葜属植物化学成分研究的进展，着重介绍了在本属植物中所发现的甾体皂甙类化合物的分离技术、结构鉴定和结构特性。     

甾体肟的合成及抗肿瘤活性的研究

利用甾体原料合成了4个3β-羟基-5-烯类甾体肟化合物,采用MTT法测定了甾体肟化合物的抗肿瘤活性.结果表明甾体肟化合物对LTEP-α-2细胞具有一定的抑制作用,随受试物浓度的增加,对细胞的抑制作用增强.16-脱氢孕甾烯醇酮肟对LTEP-α-2细胞生长抑制作用最强,IC50值为11.6μg·mL-1.     

甾体皂苷的生物活性研究进展

概述了植物中甾体皂苷的生物活性,详细介绍了其在心血管系统、抗肿瘤、增强免疫、降血糖、抗生育、杀虫、抗真菌等方面的药理作用、构效关系、临床应用及研究进展,为开发和利用甾体皂苷药用植物资源奠定基础.     

Induction of VEGF by tepoxalin does not lead to increased tumour growth in a canine osteosarcoma xenograft

The purpose of this study was to determine the impact of the non-steroidal anti-inflammatory drug tepoxalin on canine tumour cell growth and describe the changes associated with tepoxalin treatment. In vitro experiments were performed to assess tepoxalin-associated alterations in tumour cell growth. Clinically achievable tepoxalin concentrations did not significantly alter tumour cell growth in vitro. Vascular endothelial growth factor (VEGF) production and hypoxia-inducible factor-1α dose-dependently increased in vitro in the presence of tepoxalin. A canine osteosarcoma xenograft was used to determine in vivo effects of tepoxalin on tumour growth and angiogenesis. Despite increased VEGF in vitro, there was a significant growth delay associated with tepoxalin treatment. Normal dogs were administered tepoxalin to assess effects on systemic VEGF production, but not found to have significantly increased VEGF. These data suggest that tepoxalin may moderately inhibit tumour growth and may be administered as an analgesic to tumour-bearing dogs.     

Evaluating a novel analgesic strategy for ring castration of ram lambs

Objective To evaluate the analgesic efficacy of the NSAIDs flunixin and meloxicam administered locally to the scrotum before ring castration. Study design Randomised, controlled, prospective study. Animals Forty eight single born male Merino lambs. Methods Lambs, aged approximately 4 weeks, were allocated to four groups for castration. Groups were: sham control; castration + saline; castration + flunixin; castration + meloxicam. Drugs (5 mL) were administered subcutaneously around the circumference of the scrotum immediately before castration. Cortisol, rectal temperature, haematology and plasma haptoglobin were measured before and up to 48 hours after treatment. Behaviour recorded by video for 12 hours after treatment was classified as pain avoidance behaviours in the first hour and postural behaviours in three 4 hour intervals. Results Ring castration (saline group) induced a bi‐phasic increase in cortisol with peaks at 90 minutes and 24 hours but no significant changes in haematology, haptoglobin or rectal temperature. Pain avoidance behaviours were increased and teat seeking decreased. Normal lying and normal standing postures were decreased and abnormal ventral lying, statue standing, abnormal standing and total abnormal postures increased. Flunixin decreased cortisol at 90 minutes (60.3 versus 117.3 nmol L^?1) and cortisol AUC (0–6 hours), decreased elevated leg movement (2.5 versus 5.4 events) and sum of pain avoidance behaviours (8.5 versus 16.7 events), improved time spent in normal ventral lying and decreased abnormal ventral lying and total abnormal postures compared to saline treated lambs. In a similar contrast, meloxicam caused non‐significant decreases in cortisol at 90 minutes, cortisol AUC (0–6 hours) and pain avoidance behaviours, and significantly improved the postural behaviours normal ventral lying (26.7 versus 15.4%) and normal standing (13.9 versus 7.5%), and reduced abnormal standing and total abnormal postures. Physiological and behavioural responses associated with ring castration for both NSAID treatment groups were generally greater than sham controls. Conclusions and clinical relevance Locally administered NSAIDs provided partial analgesia for ring castration.     

Inheritance of steroidal glycoalkaloids in potato tuber flesh

Potato(Solanum tuberosum L.) is the third most important food crop worldwide after wheat and rice in terms of human consumption. A critical domestication trait for potato was the decrease of toxic steroidal glycoalkaloids(SGAs) in tuber flesh. Here, we used a diploid F_2 segregating population derived from a cross between S. tuberosum and the wild potato species Solanum chacoense to map the quantitative trait loci(QTLs) associated with the regulation of SGAs content in tuber flesh. In a three-year study, we identified two QTLs on chromosomes 2 and 8 affecting SGAs content in tuber flesh. The QTL on chromosome 8 harbors 38 genes that are co-expressed with the GLYCOALKALOID METABOLISM genes. These findings lay the foundation for exploiting the genes controlling SGAs content in tuber flesh and they provide a theoretical basis for the use of wild germplasm in potato breeding.     

白粉玉簪甾体皂苷提取方法研究

通过单因素实验(乙醇浓度、料液比、温度、超声时间、超声功率)和正交实验选取最适甾体皂苷提取条件。结果表明:白粉玉簪甾体皂苷最佳提取条件为乙醇浓度55%,料液比1∶22,温度50℃,超声时间55min,超声功率90W。