The structure and evolution of the spider monkey delta-globin gene

We have isolated the delta-globin gene of the New-World spider monkey, Ateles geoffroyi, and compared its nucleotide sequence with those of other primate delta- and beta-globin genes. Among primate delta-globin genes, the rate of nonsynonymous substitutions is much less than the rate of synonymous substitutions. This suggests that primate delta- globin genes may remain under evolutionary conservation, perhaps because hemoglobin A2 has an as yet unknown physiological importance.      

Using dynamic pupillometry as a simple screening tool to detect autonomic neuropathy in patients with diabetes: a pilot study

Background  

Autonomic neuropathy is a common and serious complication of diabetes. Early detection is essential to enable appropriate interventional therapy and management. Dynamic pupillometry has been proposed as a simpler and more sensitive tool to detect subclinical autonomic dysfunction. The aim of this study was to investigate pupil responsiveness in diabetic subjects with and without cardiovascular autonomic neuropathy (CAN) using dynamic pupillometry in two sets of experiments.     

一种新的肝细胞生成素（HPO）转录本及其生物学活性

利用 5′RACE技术从人胎肝组织中分离一种新形式的肝细胞生成素 (HPO 2 0 5 )cDNA ,其编码蛋白质氨基酸序列的N端较已报道的人肝细胞生成素HPO(hepatopoietin)多 80个氨基酸 ,推测其蛋白质分子量为 2 3kD。RT PCR检测HPOmRNA在多种肝癌细胞中表达 ,Western印迹可检测到 2 3kDHPO 2 0 5表达 ,表明此种形式HPO在自然状态下存在。将构建的HPO 2 0 5真核表达载体转染入COS 7细胞 ,其表达蛋白质能够刺激HepG2肝癌细胞DNA合成 ;将HPO 2 0 5、HPO和荷空表达载体分别转染入低水平表达HPO的Bel 740 2肝癌细胞株 ,发现HPO 2 0 5比HPO具有较强的激活MAPK磷酸化的活性。细胞周期分析稳定转染HPO 2 0 5 ,HPO细胞的增殖周期也支持这一结论。这些结果表明HPO 2 0 5具有刺激肝源性细胞增殖的活性 ,并提示HPO 2 0 5可能较HPO有更强的生物学活性     

固氮酶铬铁蛋白的晶体生长

在合适的结晶条件下 ,从含Cr无氨培养基中生长的固氮菌 (AzotobactervinelandiiLipmann)突变种UW3 中纯化出的CrFe蛋白可从溶液中析出深棕色斜四棱柱晶体 ,晶体最大的两条对角线长度分别可达 0 .2 5mm和 0 .12mm。PEG 80 0 0、MgCl2 、NaCl、Tris和Hepes缓冲液的浓度及结晶方法等对该蛋白的出晶率、晶核数目、晶体大小和质量都有明显影响。CrFe蛋白结晶所需的上述化合物的最适浓度与在Mn中生长的固氮菌突变种UW3 的MnFe蛋白和缺失nifZ固氮菌突变种的ΔnifZMoFe蛋白结晶所需的最适浓度有所不同。结果表明 ,该蛋白晶体可能为CrFe蛋白的晶体     

含锰固氮酶组分Ⅰ蛋白的纯化和特性

棕色固氮菌（Azotobacter vinelandii Lipmann)突变种UW3能在无Mo的无氨培养基中固氮生长,低浓度的Mn对UW3突变种生长有促进作用,从在Mn中生长的UW3菌体中分离得到的部分纯固氮酶组分Ⅰ蛋白含量有Mn和Fe原子（Fe/Mo/Mn为10．41：0．19：1．00）并有OP MoFe蛋白一半的还原乙炔和质子的活性。这种蛋白的吸收光谱和圆二色谱与MoFe蛋白存在明显的差异,含Mn蛋白的亚基分子量都与MoFe蛋白的α亚基相近。初步结果表明,这种含Mn蛋白可胡是一种固氮酶组分Ⅰ蛋白。     

The In Vitro and In Vivo Inhibitory Effects of Some Sulfonamide Derivatives on Rainbow Trout (Oncorhynchus Mykiss) Erythrocyte Carbonic Anhydrase Activity

The in vitro and in vivo inhibitory effects of 5-(3α, 12α-dihydroxy-5-β-cholanamido)-1,3,4-thiadiazole-2-sulfonamide (1), 5-(3α, 7α, 12α-trihydroxy-5-β-cholanamido)-1,3,4-thiadiazole-2-sulfonamide (2), 5-(3α, 7α, 12α-triacetoxy-5-β-cholanamido)-1,3,4-thiadiazole-2-sulfonamide (3) and acetazolamide on rainbow trout (Oncorhynchus mykiss) (RT) erythrocyte carbonic anhydrase (CA) were investigated. The RT erythrocyte CA was obtained by affinity chromatography with a yield of 20.9%, a specific activity of 422.5?EU/mg protein and a purification of 222.4-fold. The purity of the enzyme was confirmed by SDS-PAGE. Inhibitory effects of the sulfonamides and acetazolamide on the RT erythrocyte CA were determined using the CO₂-Hydratase method in vitro and in vivo studies. From in vitro studies, it was found that all the compounds inhibited CA. The obtained I₅₀ value for the sulfonamides (1), (2) and (3) and acetazolamide were 0.83, 0.049, 0.82 and 0.052?μM, respectively. From in vivo studies, it was observed that CA was inhibited by the sulfonamides (1), (2) and (3) and acetazolamide.     

西藏墨脱格当乡野生虎捕食家畜现状与保护建议

曾经在西藏东南的阔叶林中广泛分布的孟加拉虎,目前仅有一个小种群残留在墨脱县境内。2000年5－6月间,在大型家畜遭受野生虎捕食最严重的墨脱县格当乡展开调查,试图寻找减轻虎害的方法。结果表明：1994－1995年虎的捕食率达到最高,对牛和骡马的捕食率分别是17．9％和9．4％;但1996年后,捕食率分别降低到7．8％和1．8％,这可能与1996年当地曾捕杀过一头虎有关。1993－1999年间,全乡牛的数量下降了11％,但骡马数量上升了23％,这是因为当地为增加运输能力而从别处购得骡马。据反映,目前格当乡境内大约有4－5头虎。1997年和1999年,均见母虎和小虎同行,说明该种群尚有繁殖。在抽样的21户居民家中,1999年4月到2000年5月间,66．6％的人家有大型牲畜遭虎捕杀,共损失牛27头,马12匹,而自1993年以来,21户中共有18户（85．8％）,有牲畜被杀记录,共计损失117头。其中对牛的捕食率达19．7％,对马达11．9％,平均每户损失牛1．2头,骡马0．5匹。非法狩猎减少了虎的猎物如野猪、羚牛等的数量,是老虎转向家畜的主要原因之一。虎害已对格当乡群众的经济造成较大负面影响。但格当乡以及周边地区保护着中国最后的野生孟加拉虎种群,为确保虎的长期生存同时减少人－虎冲突,建议改变目前放牧方式,尽可能联合放牧、增加看护;改善放牧地条件,清除牧场周围蕨草丛;减少对羚牛等有蹄类的猎杀,以减少对老虎猎物种群的破坏;对部分家畜移入棚内试行圈养,既保护家畜,又提高乳制品产量和增加农家肥料;实行多种经营方法,建议养一些山羊和家禽;政府应该帮助安置好部分愿意外迁的居民,这样既满足这些居民的需要,同时也减轻对当地野生动物种群的压力。     

Lack of geographic variation in anonymous nuclear polymorphisms in the American oyster, Crassostrea virginica

Comparing geographic variation of noncoding nuclear DNA polymorphisms, which presumably are neutral to natural selection, with geographic variation of allozymes is potentially a good way to detect the effects of selection on allozyme polymorphisms. A previous study of four anonymous nuclear markers in the American oyster, Crassostrea virginica, found dramatic differences in allele frequency between the Gulf of Mexico and the Atlantic Ocean. In contrast, 14 allozyme polymorphisms were fairly uniform in frequency between the two areas. This led to the conclusion that all of the allozyme polymorphisms were kept uniform in frequency by balancing selection. To test the robustness of this pattern, six additional anonymous nuclear DNA polymorphisms were surveyed in oysters from Panacea, Fla, and Charleston, S.C. on the Gulf and Atlantic coasts, respectively. Unlike the previously studied DNA markers, the six DNA polymorphisms examined here show geographic variation that is not significantly greater than that of allozymes. The reason for the discrepancy between the two sets of DNA polymorphisms is unclear.