Polyphosphate kinase activity in yeast vacuoles]

The enzyme polyphosphate kinase (ATP: Polyphosphate phosphotransferase EC 2.7.4.1) relating to the class of transferases was detected in the vacuoles of Saccharomyces carlsbergensis yeast. The direct ATP: Polyphosphate phosphotransferase reaction resulting in the synthesis of polyphosphates from ATP was shown to occur mainly in vacuoles. The localization of the reverse polyphosphate: ADP phosphatransferase reaction was not established in any of the subcellular yeast fractions studied. The activity of the direct reaction in the yeast protoplasts makes up about 1% of the reverse one, but in vacuoles it is significantly higher and makes up to 19%. Under activation of biochemical processes involved in the production of cell wall components by protoplasts, vacuolar polyphosphates work mainly in the direction of ATP synthesis at the expense of polyphosphates accumulated in vacuoles.     

烈香杜鹃的离体培养和高效植株再生

以烈香杜鹃嫩茎为外植体,应用均匀设计法筛选其最适合的嫩茎基部直接再生芽苗和生根培养基。结果表明,最适合烈香杜鹃嫩茎基部直接再生芽苗的诱导培养基为DR＋2．30mg·L-1 TDZ＋0．05mg·L-1 IAA＋1．80mg·L-1 KT,诱导率为99．6％;生根培养基为1／2DR＋0．07mg·L-1 IAA＋0．02mg·L-1NAA,生根率达99．7％以上。以再生植株茎节为材料进行快速繁殖,在35d的培养周期内,每段增殖倍数平均达5以上。     

CRBGP通过抑制FAK-AKT通路和白介素-6的分泌抑制胶质瘤U251细胞的活性

目的 电压门控钠通道(voltage-gated sodium channels,VGSCs)表达于胶质瘤U251细胞,并影响U251细胞的增殖、侵袭和凋亡.富含半胱氨酸的颊腺蛋白(cysteine-rich buccal gland protein,CRBGP)是一种从日本七鳃鳗颊腺中分离出来的VGSCs阻断剂.本文...     

The carbohydrate moiety of α-galactosidase from Trichoderma reesei

a-Galactosidase from Trichoderma reesei is a glycoprotein that contains O- and N-linked carbohydrate chains. There are 6 O-linked glycans per protein molecule that are linked to serine and threonine and can be released by b-elimination. Among these are monomers: D-glucose, D-mannose, and D-galactose; dimers: a1-6 D-mannopyranosyl- a-D-glycopyranoside and a1-6 D-glucopyranosyl- a-D-galactopyranoside and one trimer: a-D-glucopyranosyl- a1-2 D-mannopyranosyl- a1-6 D-galac-topyranoside. N-linked glycans are of the mannose-rich type and may be released by treating the protein with Endo- b-N-acetyl glycosaminidase F or by hydrozinolysis. The enzyme was deglycosylated with Endo- b- N-acetyl glycosaminidase F as well as with a number of exoglycosidases that partially remove the terminal residues of O-linked glycans. The effect of enzymatic deglycosylation on the properties of a-galactosidase has been considered. The effects of tunicamycin and 2-deoxyglucose on the secretion and glycosylation of the enzyme during culture growth have been analysed. The presence of two glycoforms of a-glactosidase differing in the number of N-linked carbohydrate chains and the microheterogeneity of the carbohydrate moiety of the enzyme are described. This revised version was published online in August 2006 with corrections to the Cover Date.     

甲亢甲低患者肝纤维化指标检测的临床意义分析

目的：探讨甲状腺功能亢进（甲亢）、甲状腺功能减低（甲低）与肝纤维化指标的关系及其可能的机制。方法：采用放射免疫分析法（R1A）检测57例甲亢患者、43例甲低患者、39例甲亢治疗后甲状腺激素正常者和50例健康成人的血清Ⅳ型胶原（1V-C）、Ⅲ型前胶原（PCⅢ）、透明质酸（HA）、层粘连蛋白（LN）、T3、T4、FT3、FT4、TSH、TGA、TMA含量。结果：甲亢患者组血清中1V-C、PCⅢ含量比正常对照组及甲低患者组显著性增高（P〈0.05）;治疗后甲状腺激素下降,1V-C、PCⅢ含量也随之下降（与治疗前比较P〈0.01）;HA、LN在四组中无显著性差异（P〉0.05）,在甲亢治疗前后无显著性差异（P〉0.05）。各项肝纤维化指标与TGA、TMA的阳性率无关。结论：甲亢患者可有不同程度的肝功能损害,血清中甲状腺激素水平增高时,1V-C、PCⅢ水平也增高,在用1V-C、PCⅢ判断肝纤维化时应注意有无甲状腺疾病特别是甲亢。未发现HA、LN含量与甲状腺激素水平的关系。     

Evaluation of zona pellucida birefringence intensity during in vitro maturation of oocytes from stimulated cycles

Background  

This study evaluated whether there is a relationship between the zona pellucida birefringence (ZP-BF) intensity and the nuclear (NM) and cytoplasmic (CM) in vitro maturation of human oocytes from stimulated cycles.     

氦氧饱和高气压暴露对铜绿假单胞菌毒力表型的诱导调节

研究氦氧饱和高气压暴露对铜绿假单胞菌与急性侵袭感染相关的主要毒力因子表型的影响。分别检测暴露前后铜绿假单胞菌的生长速度、运动能力,对乙酰胺的分解能力和培养细胞外液中绿脓菌素、弹性蛋白酶的分泌水平和活性。在动物水平验证毒力的变化。结果显示,经4.5 MPa氦氧饱和加压暴露后,与对照组相比铜绿假单胞菌的生长增殖、运动能力和对乙酰胺的分解能力增强,绿脓菌素分泌增加,弹性蛋白酶活性增强;暴露后细菌对实验小鼠的毒性增加。因此氦氧饱和高气压环境对铜绿假单胞菌的毒力表型有正调控作用。     

污染环境下单种群模型生存阈值

本论文研究了污染环境下毒素对单种群生存的影响。在环境容纳量较小的假设下建立了生物种群模型,在该模型中不但考虑了环境毒素浓度对生物个体生存的影响,还考虑了生物个体从食物链中吸收的毒素对其影响。通过研究得到种群一致持续生存和若平均持续生存的充分条件,同时得到种群持续生存依赖于模型参数和生物个体体内毒素净化率的某些充分条件．