Apoptotic activity of frog Bombina maxima skin albumin

Albumin, the most abundant protein components of blood plasma, is synthesized and secreted by liver cells in vertebrates. Recently, it was demonstrated that frog Bombina maxima albumin is also expressed in skin. Both B. maxima albumins from skin and serum

Analysis of mitochondrial DNA polymorphisms in Guangdong Han Chinese

Previous investigations on Chinese mitochondrial DNA (mtDNA) variation revealed that the matrilineal gene pool of southern Han Chinese is rather complex, with much higher genetic diversity and more basal/ancient lineages than the northern Hans. The extrem

我国中药来源的抗HIV天然化合物研究进展

由于迄今仍无艾滋病(acquired immunodeficiency syndrome,AIDS)疫苗问世,抗人类免疫缺陷病毒(human immunodeficiency virus,HIV)药物仍然是艾滋病治疗的主要手段。传统中药和药用植物来源的天然化合物具有结构多样性、毒性较低、来源广泛等特点,因而在防治艾滋病方面有着独特的优势和巨大的潜力。研究者已经对天然化合物抗HIV作用进行了大量研究,并取得了可喜的成绩,发现了一些生物碱、香豆素、木脂素、黄酮类、萜类、鞣质类、多糖类、蛋白质和多肽类等天然化合物具有抗HIV的活性。然而,多数研究都是在体外试验完成的,大多数天然化合物体外抗HIV活性偏低,而且抗HIV的靶点仍不十分清楚。本文结合笔者实验室研究工作,重点介绍近年来我国传统中药来源的抗HIV活性较强的天然化合物研究进展。

Octanorcucurbitane and cucurbitane triterpenoids from the tubers of Hemsleya endecaphylla with HIV-1 inhibitory activity

Two new cucurbitacins, endecaphyllacins A (1) and B (2), together with six known analogues (3-8), were isolated from the tubers of Hemsleya endecaphylla. The structures of 1 and 2 were elucidated by NMR and MS spectroscopic analysis. The relative stereoch

Anti-HIV Activities of the Compounds Isolated from Polygonum cuspidatum and Polygonum multiflorum

The 70% EtOH extract of Polygonum cuspidatum showed inhibitory action against HIV-1-induced syncytium formation at non-cytotoxic concentrations in vitro with a 50% effective concentration (EC50) of 13.94 +/- 3.41 mu g/mL. Through bioactivity-guided fractionation, 20 phenolic compounds, including eight stilbenoids, were isolated from the roots of Polygonum cuspidatum, and their anti-HIV-1 activities were evaluated. Results showed that compounds 1, 13, 14, and 16 demonstrated fairly strong antiviral activity against HIV-1-induced cytopathic effects in C8166 lymphocytes at non-cytotoxic concentrations, with EC50 values of 4.37 +/- 1.96 mu g/mL, 19.97 +/- 5.09, 14.4 +/- 1.34 mu g/mL, and 11.29 +/- 6.26 mu g/mL and therapeutic index (TI) values of 8.12, > 10.02, > 13.89, and > 17.71, respectively. Other compounds showed either weak or no effects. Compound 6 also showed weak inhibition (153.42 +/- 19.25 mu g/mL); however, it possesses very good water solubility and showed almost no cytotoxicity (> 2000 mu g/mL), therefore achieving a fairly good TI (13.04). The activities of the two compounds (3 and 18) from Polygonum multiflorum were also assayed. The relationship between molecular structures and their bioactivities was also discussed.

Sleeping sites, sleeping trees, and sleep-related behaviors of black crested gibbons (Nomascus concolor jingdongensis) at Mt. Wuliang, central Yunnan, China

Data on sleep-related behaviors were collected for a group of central Yunnan black crested gibbons (Nomascus concolor jingdongensis) at Mt. Wuliang, Yunnan, China from March 2005 to April 2006. Members of the group usually formed four sleeping units (adult male and juvenile, adult female with one semi-dependent black infant, adult female with one dependent yellow infant, and subadult male) spread over different sleeping trees. Individuals or units preferred specific areas to sleep; all sleeping sites were situated in primary forest, mostly (77%) between 2,200 and 2,400 m in elevation. They tended to sleep in the tallest and thickest trees with large crowns on steep slopes and near important food patches. Factors influencing sleeping site selection were (1) tree characteristics, (2) accessibility, and (3) easy escape. Few sleeping trees were used repeatedly by the same or other members of the group. The gibbons entered the sleeping trees on average 128 min before sunset and left the sleeping trees on average 33 min after sunrise. The lag between the first and last individual entering the trees was on average 17.8 min. We suggest that sleep-related behaviors are primarily adaptations to minimize the risk of being detected by predators. Sleeping trees may be chosen to make approach and attack difficult for the predator, and to provide an easy escape route in the dark. In response to cold temperatures in a higher habitat, gibbons usually sit and huddle together during the night, and in the cold season they tend to sleep on ferns and/or orchids.

Phylogenetic relationships among Rhacophorinae (Rhacophoridae, Anura, Amphibia), with an emphasis on the Chinese species

The partial nucleotide sequence of mitochondrial 12S and 16S rRNA genes was determined for 23 Chinese species of Rhaeophoridae (Amphibia: Anura), representing four of the eight recognized genera. Using Buergeriinae as the outgroup, phylogenetic analyses (

神经束路电镜追踪中影响HRP-TMB反应产物因素的分析

采用HRP-TMB-ST法对小鼠延髓下橄榄核下端外侧网状核细胞的HRP-TMB反应产物影响因素分析表明: (1)较高的pH值(7.0以上)是反应产物消失的关键因素; 02mol/L PB, pH5.0-6.0 对HRP-TMB反应灵敏度、反应产物的稳定性及组织超微结构的保存是适宜的; 当pH值相 同时, 缓冲液浓度不同, 反应产物消失的程度和速度也不相同。(2)酒精有稳定产物的作用 。(3)反应前的预浸、灌注液的成分、浓度和固定时间等则与反应产物的丢失无关。此外, 用pH5.5和pH7.0的缓冲液处理的切片经DAB强化、锇化后, 组织的超微结构无明显的差异。 图2表3参18

笼养大紫胸鹦鹉取食活动

笼养大紫胸鹦鹉取食活动占观察时间的14.51%，是其主要行为活动之一。日取食活动呈现早（7：00#approx#10：00）、晚（15：00#approx#19：00）2个明显的高峰。每日取食（32.12+ -14.28）次，累计日取食时间（153.23+ -73.11）min。每次取食的时间平均为（5.29+ -1.06）min。两性和成幼间以及不同时期的取食活动有一定的差异。在整个取食过程中，除拾取（45.47%）和咀嚼（46.49%）两种取食行为外，还有身体护理（2.51%）、运动（3.59%）、静栖（1.72%）、攻击（0.12%）、求偶（0.1%）等活动出现。逐步回归分析表明：影响大紫胸鹦鹉成鸟取食活动的主要因素是生物学因素；5月龄以前幼鸟的取食行为除受生物学因素的影响外，还与温度有一定的关系。

表皮生长因子对猕猴胚胎角膜上皮组织增殖效应的研究

离体培养试验表明，小鼠颌下腺表皮生长因子对离体培养猕猴胚胎眼角膜上皮组织具有显著促进细胞增殖和分化的效应。培养4d的实验组角膜上皮的厚度，上皮细胞增殖层数以及上皮组织中基底层细胞核与表层细胞核两者的比率均较正常猴胚角膜增长3倍。与此同时培养4d的实验组角膜上皮厚度和上皮细胞的层数，都达到成年猴正常角膜上皮的结构水平。

小分子对大分子反应的控制作用

生物体系中各种大分子的反应无一例外地都涉及多种小分子的参与. 这些小分子, 如小肽、有机小分子和无机离子等, 在大分子的反应中是不可缺的, 有些对反应的进程起着关键性作用. 小分子究竟从哪些方面影响或控制大分子的反应进程?

The in vivo synaptic plasticity mechanism of EGb 761-induced enhancement of spatial learning and memory in aged rats

1 It has not been uniform to date that the Ginkgo biloba extracts enhance cognitive function in aged animals, and the mechanisms of action remain difficult to elucidate. In this study, the Morris water maze task and electrophysiological methods were used