糖在猕猴精子低温冷冻保存过程中的作用

TTE或TEST防冻液在冻存猕猴精子时产生不同结果，其主要不同在于防冻液中糖成分的不同。实验结果表明，冷冻复苏过程对精子结构产生了影响，TTE法低温保存的猕猴精子的头部的质膜出现少许皱褶或泡化现象，但精子的顶体、核或是精子尾部的结构与鲜精的结构基本相似。猕猴精子经TEST法低温保存后，大部分精子结构则发生了明显的变化，精子膜、顶体和精子核明显泡化、损伤或破裂，精子尾部不能分辨出正常的超微结构。这提示，可能由于TTE防冻液中复杂的糖成分在降温/复苏过程对精子起到了较好的协同冷冻保护作用；而TEST防冻液中单一的糖成分不能完全保护精子避免低温损伤，低温保存过程破坏了精子的结构，并影响了复苏后精子体外存活能力与受精能力。

滇中高原湖泊鱼类多样性的研究‘

依据历年馆藏的鱼类标本和资料，采用多元逐步回归与多项式逐步回归的分析方法，系统分析了滇中６个高原湖泊鱼类的物种丰度、特有种以及属的数目与７个主要湖泊环境因子之间的关系。分析结果显示，控制湖泊鱼类物种丰度、特有种数和属数的关键湖泊环境因子是湖泊面积和湖岸线长度；其中与湖泊面积呈显著正相关，而与湖岸线长度呈负相关。分析不停留于这一常规的横向比较，而是从历史生物地理学的角度，更深入一步揭示了滇中６个湖泊鱼类多样性的演化实质上是受湖泊的发育阶段所控制的。

一篇探索真核细胞核起源的力作——读李靖炎先生的长篇近作“The primitive nucleus model and the origin of the cell nucleus”

《胞内共生与细胞研究》( 《Endocytobiosis and Cell Research》)是由国际胞内共生学会(International Society of Endocytobiology, ISE)主办的期刊, 它主要发表有关内共生物(endosy mbioses)和真核细胞的起源、发展、分化、进化和系统发育的研究论文. 在胞内共生和真核细胞的起源进化研究领域享有声誉. 去年该杂志发表了我国学者李靖炎先生的长篇论著“The primitive nucleus model and the origin of the cell nucleus(原始细胞核的模型与细胞核的起源)”(见1999, 13(1-3):1-86). 国外一家 SCI 收录的专业性刊物为中国学者发表一篇长达86页的 Review, 实不多见, 是我国学者在此领域的殊荣。

撒坝猪、大河猪染色体比较研究

采用外周血淋巴细胞培养方法,以及C-带、G-带和银染技术,对云南地方猪种撒坝猪、大河猪进行显带染色体研究。测量了各号染色体的相对长度、着丝点指数及臂比,Ag-NORs定位于7号和10号染色体。撒坝猪、大河猪的G-带带型与其它家猪相似,C-带和Ag-NORs具有多态性。撒坝猪和大河猪的C-带和Ag-NORs存在一定差异。

中国鼠兔一新种--片马黑鼠兔

报道了采自云南片马的鼠兔属1新种,以其体色在鼠兔属中最为深黑为其主要特征而命名为片马黑鼠兔Ochotona nigritia sp. nov.。正模标本保存在中国科学院昆明动物研究所,副模标本保存在云南省流行病防治研究所。

TMVA, a novel GPIb-binding protein, significantly prevents platelet microthrombi formation and prolongs discordant cardiac xenograft survival

In xenotransplantation, donor endothelium is the first target of immunological attack. Activation of the endothelial cell by preformed natural antibodies leads to platelet binding via the interaction of the glycoprotein (GP) Ib and von Willebrand factor (vWF). TMVA is a novel GPIb-binding protein purified from the venom of Trimeresurus mucrosquamatus. In this study, the inhibitory effect of TMVA on platelet aggregation in rats and the effect on discordant guinea pig-to-rat cardiac xenograft survival were investigated. Three doses (8, 20 or 40 mug/kg) of TMVA were infused intravenously to 30 rats respectively. Platelet aggregation rate was assayed 0.5, 12, and 24 h after TMVA administration. Wister rats underwent guinea pig cardiac cervical heterotopic transplantation using single dosing of TMVA (20 mug/kg, i.v., 0.5 h before reperfusion). Additionally, levels of TXB2 and 6-keto-PGF(1alpha) within rejected graft tissues were determined by radioimmunoassay. Treatment with TMVA at a dose of 20 or 40 mug/kg resulted in complete inhibition of platelet aggregation 0.5 h after TMVA administration. Rats receiving guinea pig cardiac xenografts after TMVA therapy had significantly prolonged xenograft survival. Histologic and immunopathologic analysis of cardiac xenografts in TMVA treatment group showed no intragraft platelet microthrombi formation and fibrin deposition. Additionally, the ratio of 6-keto-PGF(1alpha) to TXB2 in TMVA treatment group was significantly higher than those in control group. We conclude that the use of this novel GPIb-binding protein was very effective in preventing platelet microthrombi formation and fibrin deposition in a guinea pig-to-rat model and resulted in prolongation of xenograft survival. The increased ratio of PGI(2)/TXA(2) in TMVA treatment group may protect xenografts from the endothelial cell activation and contribute to the prolongation of xenograft survival.