Novel P450(17alpha) inhibitors: 17-(2'-oxazolyl)- and 17-(2'-thiazolyl)-androstene derivatives

Twelve 17-(2'-oxazolyl)- and 17-(2'-thiazolyl)-androsta-5,16-diene derivatives were designed and synthesized from 3 beta-acetoxy-pregna-5,16-dien-20-one (1b) as inhibitors of 17 alpha-hydroxylase-C(17,20)-lyase (P450(17 alpha)). Potent inhibitors of this enzyme could be of value as treatment of prostate cancer. Two substituents (methyl and phenyl) were introduced either at their 4'- or 5'-position in order to investigate their structure-activity relationship. Due to the 16,17-double bond, 17-thiazoles were generally obtained in low yield. The pharmacological results showed that the compounds containing 17-(2'-oxazolyl) (14c) and 17-(2'-thiazolyl) (8c) (41.5%) demonstrated reasonable inhibition against P450(17 alpha). Their 3-acetate (13c and 7c) were less potent than their 3-OH counterparts. The introduction of a phenyl or methyl group generally decreased inhibitory activity. Surprisingly, 17-(5'-methyl-2'-thiazolyl) (12a) was the most potent compound in this series and was almost as potent as L-39, which has good antitumor activity.     

Mg-ATPase and CA2+ activated myosin ATPase activity in ventricular myofibrils from non-failing and diseased human hearts – effects of calcium sensitizing agents MCI-154, DPI 201–106, and caffeine

We investigated the effects of two purported calcium sensitizing agents, MCI-154 and DPI 201–106, and a known calcium sensitizer caffeine on Mg-ATPase (myofibrillar ATPase) and myosin ATPase activity of left ventricular myofibrils isolated from non-failing, idiopathic (IDCM) and ischemic cardiomyopathic (ISCM) human hearts (i.e. failing hearts). The myofibrillar ATPase activity of non-failing myofibrils was higher than that of diseased myofibrils. MCI-154 increased myofibrillar ATPase Ca²⁺ sensitivity in myofibrils from non-failing and failing human hearts. Effects of caffeine similarly increased Ca²⁺ sensitivity. Effects of DPI 201–106 were, however, different. Only at the 10^–6 M concentration was a significant increase in myofibrillar ATPase calcium sensitivity seen in myofibrils from non-failing human hearts. In contrast, in myofibrils from failing hearts, DPI 201–106 caused a concentration-dependent increase in myofibrillar ATPase Ca²⁺ sensitivity. Myosin ATPase activity in failing myocardium was also decreased. In the presence of MCI-154, myosin ATPase activity increased by 11, 19, and 24% for non-failing, IDCM, and ISCM hearts, respectively. DPI 201–106 caused an increase in the enzymatic activity of less than 5% for all preparations, and caffeine induced an increase of 4, 11, and 10% in non-failing, IDCM and ISCM hearts, respectively. The mechanism of restoring the myofibrillar Ca²⁺ sensitivity and myosin enzymatic activity in diseased human hearts is most likely due to enhancement of the Ca²⁺ activation of the contractile apparatus induced by these agents. We propose that myosin light chain-related regulation may play a complementary role to the troponin-related regulation of myocardial contractility.     

Synthesis of beta-substituted cationic porphyrins and their interactions with DNA

The beta-substituted cationic porphyrins (7, 8 and 10) have been synthesized and their interactions with plasmid DNA investigated. We found that substituents at the beta-position of porphyrins (7 and 8) have apparently affected their interactions with DNA compared with non-beta-substituted porphyrins (10).     

鳜脑干组织学与重建研究

采用银浸染,美蓝及Ｈ．Ｅ染色技术对５尾鳜成鱼的脑干进行了组织学研究,并在此基础上对春各主要神经核团及神经束空间构型及走向进行了探讨,旨在为研究鳜脑的功能提供生资料。鳜脑干结构与其它硬骨鱼相似,囊括了除第１对脑神经之外的９对脑神经中枢。并且感觉中枢多集中于脑干背侧;运动中枢集中于脑干腹侧。     

山地麻蜥越冬及其耐饥力的观察

据调查,徐州山地麻蜥的入蛰时间为１２月中旬;出蛰时间为翌年２月中旬,冬眠期为２个月左右。生活在丘陵山地的山地麻蜥是穴居在大石块下松土中过冬的。冬眠期的活动与温度高底有一定的关系。冬眠期山地麻蜥有较强的耐饥能力。     

刺槐上分离的花生矮化病毒的研究

刺槐花叶病是我国北方刺槐（Ｒｏｂｉｎｉａｐｓｅｕｄｏａｃａｃｉａ）常见病害。１９８７～１９９５年对河南、河北、山东和北京部分地区刺槐进行调查,刺槐花叶病发病率为４％～８７．５％。该病害主要特征是：叶片出现浅绿与绿色相间带有疱疹的花叶症状,叶缘波状扭...     

不同水分条件下春小麦种群中个体大小不整齐性及遗传学分析不同水分条件下春小麦种群中个体大小不整齐性及遗传学分析

 种群内个体大小不整齐性是种群数量结构的主要指标。本文研究了不同水分条件下,3个品种春小麦种群个体大小不整齐性的建立及变化规律。对春小麦种群不整齐性的遗传学分析表明：遗传结构与随机环境修饰对种群数量结构形成的相对重要性,因水分条件不同而异。种群不整齐性在自然选择中的作用可用下列简单模型表示：CSo＝SH×hSH2 CSo：自然选择强度;SH：大小不整齐性;hSH2：不整齐性的遗传力。     

肺音信号分析系统研制

本文研制的肺音信号检测与分析系统,具有肺音信号采集、肺音图显示、肺音信号的 时域分析等项功能。     

Impact of Small Groups with Heterogeneous Preference on Behavioral Evolution in Population Evacuation

Up to now, there have been a great number of mechanisms to explain the individual behavior and population traits, which seem of particular significance in evolutionary biology and social behavior analysis. Among them, small groups and heterogeneity are two useful frameworks to the above issue. However, vast majority of existing works separately consider both scenarios, which is inconsistent with realistic cases in our life. Here we propose the evolutionary games of heterogeneous small groups (namely, different small groups possess different preferences to dilemma) to study the collective behavior in population evacuation. Importantly, players usually face completely different dilemmas inside and outside the small groups. By means of numerous computation simulations, it is unveiled that the ratio of players in one certain small group directly decides the final behavior of the whole population. Moreover, it can also be concluded that heterogeneous degree of preference for different small groups plays a key role in the behavior traits of the system, which may validate some realistic social observations. The proposed framework is thus universally applicable and may shed new light into the solution of social dilemmas.