圈养雌性马麝发情交配格局同行为发生频次的关系

于2004年8月～2005年1月,采用焦点取样连续记录法,对甘肃兴隆山自然保护区马麝繁育中心的雌性马麝Moschus sifanicus进行了行为取样.按雌麝的发情格局,将样本动物区分为正常发情和不发情个体,并对两类雌麝在非交配季节(6～10月)和交配季节(11 月～翌年1月)的行为格局分别进行了比较分析.结果 表明,正常发情和不发情雌麝的总体行为格局并无大的差异,但在非交配季节,正常发情雌麝的运动频次显著多于不发情雌麝,后者的摄食频次较多,此外,雌麝(仅为正常发情)在交配季节有蹭尾行为的表达,正常发情雌麝的蹭尾行为频次显著多于不发情雌麝(无此行为表达,频次为0值).本研究结果可为圈养雌麝的发情格局的预测及区分提供参考.     

The associations of IL-18 serum levels and promoter polymorphism with tacrolimus pharmacokinetics and hepatic allograft dysfunction in Chinese liver transplantation recipients

Interleukin 18 (IL-18) is a potent proinflammatory cytokine, which promotes the secretions of TNF-α, IL-1β, IL-2 and IFN-γ. All those inflammatory cytokines can influence the CYP450 and MDR dependent drug disposition. On the other side, those cytokines can induce hepatic allograft dysfunction. We investigated the effects of serum IL-18 and IL-18 gene promoter polymorphisms on tacrolimus pharmacokinetics and hepatic allograft dysfunction in liver transplant recipients. A total of 155 liver transplant recipients were enrolled into this study (34 females and 121 males). The mean follow-up was 52 months (range 16-96 months).The total liver transplant recipients were divided into hepatic allograft dysfunction (N = 14) and no hepatic allograft dysfunction (N = 141). We studied two single-nucleotide polymorphisms in the promoter region of IL-18 gene at the position G-137C (rs187238) and A-607C (rs1946518) by HRM analysis (high-resolution melting curve analysis). Tacrolimus dosage, tacrolimus blood concentration, serum levels of IL-18 and IFN-γ were also investigated. We found the recipients with higher IL-18 and IFN-γ serum levels had lower tacrolimus concentration/dose (C/D) ratios (P < 0.05). In the mean time, after transplantation hepatic allograft dysfunction was more likely to happen to those recipients. However, there was no significant difference in the frequencies of A-607C and G-137C allelic distribution in recipients' tacrolimus concentration/dose (C/D) ratios. This study identifies IL-18 reduced tacrolimus concentration/dose (C/D) ratio through up regulation of P-glycoprotein (P-gp).     

Heavy metal accumulation in iron plaque and growth of rice plants upon exposure to single and combined contamination by copper, cadmium and lead

A pot experiment was conducted to evaluate the bioaccumulation of heavy metals and growth response of rice plants after exposure to single and combined contamination by Cu, Cd and Pb. The results showed that the biomass production was not significantly affected by either single or combined treatment of Cu, Cd and Pb. Adding Cu (Cd, or Pb) separately all increased concentrations of the respective element in root and shoot (p < 0.001). In the combined contamination, Pb promoted both root and shoot absorption of Cu and Cd (p < 0.001), and Cu affected Cd and Pb absorption in the root, but Pb concentrations in both root and shoot were not affected by Cd application. The formation of iron plaques varied obviously with soil types. Heavy metal accumulation in iron plaques was induced by the three elements (p < 0.001). Furthermore, the three heavy metals exhibited an interactive relationship as measured by the Cu, Cd, Pb and Fe concentrations in root surface iron plaques. The iron plaques partially inhibited transfer of Pb to root and shoot, but no such effect was observed for Cu and Cd. This research indicates that the interaction among different heavy metal elements is very complex. It is very important to have a clear understanding on the associated mechanism and the consequential impact on plant growth.     

Pressure-induced endothelial Ca(2+) oscillations in lung capillaries

Endothelial second messenger responses may contribute to the pathology of high vascular pressure but remain poorly understood because of the lack of direct in situ quantification. In lung venular capillaries, we determined endothelial cytosolic Ca(2+) concentration [Ca(2+)](i) by the fura 2 ratioing method. Pressure elevation increased mean endothelial [Ca(2+)](i) by Ca(2+) influx through gadolinium-inhibitable channels and amplified [Ca(2+)](i) oscillations by Ca(2+) release from intracellular stores. Endothelial [Ca(2+)](i) transients were induced by pressure elevations of as little as 5 cmH(2)O and increased linearly with higher pressures. Heptanol inhibition of [Ca(2+)](i) oscillations in a subset of endothelial cells indicated that oscillations originated from pacemaker endothelial cells and were propagated to adjacent nonpacemaker cells by gap junctional communication. Our findings indicate the presence of a sensitive, active endothelial response to pressure challenge in lung venular capillaries that may be relevant in the pathogenesis of pressure-induced lung microvascular injury.     

Electron microscopy: essentials for viral structure, morphogenesis and rapid diagnosis

Electron microscopy(EM) should be used in the front line for detection of agents in emergencies and bioterrorism,on accounts of its speed and accuracy.However,the number of EM diagnostic laboratories has decreased considerably and an increasing number of people encounter difficulties with EM results.Therefore,the research on viral structure and morphology has become important in EM diagnostic practice.EM has several technological advantages,and should be a fundamental tool in clinical diagnosis of viruses,particularly when agents are unknown or unsuspected.In this article,we review the historical contribution of EM to virology,and its use in virus differentiation,localization of specific virus antigens,virus-cell interaction,and viral morphogenesis.It is essential that EM investigations are based on clinical and comprehensive pathogenesis data from light or confocal microscopy.Furthermore,avoidance of artifacts or false results is necessary to exploit fully the advantages while minimizing its limitations.     

线粒体DNA缺失与神经肌肉性疾病的研究

应用PCR技术对13例神经肌肉疾病患者的线粒体DNA缺失进行了研究。结果表明,其中二例肢带型肌营养不良症患者骨骼肌组织和一例帕金森氏病患者的血细胞线粒体DNA中存在至少526bp的缺失。提示线粒体突变在一些神经肌肉性疾病的发生中起一定的作用。 Abstract: Using PCR technique,we analysed the skeletal muscle and blood of 13 patients with neuromuscular disaeases.The results show that a mutant mitochondrial DNA with at least 526bp deletion exits in the skeletal muscles of 2 patients with Erb muscular dystrophy and in the blood of a patients with Parkinson’s disease.From our results,mitochondrial DNA mutations could be an important contributory factor to neuromuscular diseases.     

Molecular cloning and characterization of a novel human protein phosphatase,LMW-DSP3

Reversible phosphorylation is recognized to be a major mechanism for the control of intracellular events in eukaryotic cells. From a human fetal brain cDNA library, we isolated a cDNA clone encoding a novel dual specificity protein phosphatase, which showed 88% identity with previously reported mouse LMW-DSP3 at the amino acid level. The deduced protein had a single dual-specificity phosphatase catalytic domain, and lacked a cdc25 homology domain. LMW-DSP3 was expressed in the heart, lung, liver, and pancreas, and the expression level in the pancreas was highest. The LMW-DSP3 gene was located in human chromosome 2q32, and consisted of five exons spanning 21kb of human genomic DNA. LMW-DSP3 fused to GST showed phosphatase activity towards p-nitrophenyl phosphate which was optimal at pH 7.0 and 40 degrees C, and the activity was enhanced by Ca(2+) and Mn(2+). The phosphatase activity of LMW-DSP3 was inhibited by orthovanate. LMW-DSP3 showed phosphatase activity toward oligopeptides containing pSer/Thr and pTyr, indicating that LMW-DSP3 is a protein phosphatase with dual substrate specificity.