Structure and anti-HIV activity of micrandilactones B and C, new nortriterpenoids possessing a unique skeleton from Schisandra micrantha

Two new highly oxygenated nortriterpenoids with a unique norcycloartane skeleton, micrandilactones B and C (1-2), were isolated from Schisandra micrantha; micrandilactone C ( 2) exhibited an EC50 value of 7.71 mu g/mL (SI > 25.94) against HIV-1 replication with minimal cytotoxicity, and the potent anti-HIV-1 activity and unique structural features of 2 make it a promising lead for therapeutic development of a new generation of anti-HIV drug.

Dichotomains A and B: Two new highly oxygenated phenolic derivatives from Dicranopteris dichotoma

Dichotomains A (1) and B (2), two new highly oxygenated phenolic derivatives that feature a spirodilactone moiety in their structures, were isolated from the fronds of Dicranopteris dichotoma. Their structures were elucidated on the basis of NMR and MS sp

Sphenadilactones A and B, two novel nortriterpenoids from Schisandra sphenanthera

Two novel nortriterpenoid compounds, sphenadilactones A (1) and B (2), have been isolated from the leaves and stems of Schisandra sphenanthera. The structural elucidation of 1 and 2 was accomplished by extensive NMR analysis. The relative stereochemistry

Phylogenetic relationships in genus Niviventer (Rodentia : Muridae) in China inferred from complete mitochondrial cytochrome b gene

Chinese species of the genus Niviventer, predominantly distributed in the southeastern Tibetan Plateau and in Taiwan, are a diverse group and have not yet received a thorough molecular phylogenetic analysis. Here, we reconstructed the phylogenetic relatio

Rubriflordilactones A and B, two novel bisnortriterpenoids from Schisandra rubriflora and their biological activities

Rubriflordilactones A (1) and B (2), two novel highly unsaturated rearranged bisnortriterpenoids possessing a biosynthetically modified aromatic D-ring, were isolated from the leaves and stems of Schisandra rubriflora. Their structures were established on

Przewalskin B, a novel diterpenoid with an unprecedented skeleton from Salvia przewalskii maxim

[GRAPHIC] Przewalskin B (1), a novel diterpenoid possessing a unique skeleton, was isolated from a Chinese medicinal plant Salvia przewalskii. Its structure and relative stereochemistry were elucidated by extensive NMR analysis and a single-crystal X-ray

Schilancidilactones A and B: two novel tetranortriterpenoids with an unprecedented skeleton from Schisandra lancifolia

Schilancidilactones A (1) and B (2). two novel tetranortriterpenoids possessing an unprecedented skeleton, have been isolated from the stems of Schisandra lancifolia. Their structures were elucidated on the basis of extensive spectroscopic analysis. The r

Molecular phylogeny of five species of Dremomys (Rodentia : Sciuridae), inferred from cytochrome b gene sequences

Analyses of the mitochondrial cytochrome b gene (1140 bp) showed that Dremomys lokriah, D. pernyi, D. pyrrhomerus, D. rufigenis and D. gularis all are separate species. Dremomys pyrrhomerus showed 8.5% sequence variation from D. rufigenis, and the level o

肉、奶牛B超活体取卵方法

本发明涉及一种肉、奶牛B超活体取卵方法，属生物技术领域。本方法的吸卵真空泵的压力为50-90mmHg，吸卵液为含0.5-1％,青-链霉素和5-10IU肝素的磷酸缓冲液，洗卵液为含5-12％,BCS的磷酸缓冲液和改良的基础培养液-Hepes液；采卵频率为1次/4天/头；穿刺对象为所有直径≥2mm的卵泡；取1-3级的卵母细胞分装、备用；对7-8岁的供体经产牛按程序注射等量的外源性FSH，总量为30-55μg；对≥14岁的老年牛按程序肌肉注射总量为150-200μg的外源性FSH，以提高卵母细胞发育潜能。本发明的优点在于，从活体可重复、无损伤获取卵母细胞；≥2mm直径卵泡作为穿刺对象和每4天1次的取卵频率保证了卵母细胞的质量和发育同步性；用外源性FSH诱导可提高卵母细胞的发育潜能；本方法的取卵效果佳。

肉牛B超活体取卵效果的研究

对肉牛(莫累灰×婆罗门) 利用B 超活体取卵,研究不同年龄和促卵泡素(FSH) 对平均卵泡数、平均卵母细 胞数、平均可利用卵母细胞(COC) 数、卵母细胞回收率、COC 回收率、囊胚率和平均囊胚数的影响。结果表明:肉牛 B 超活体所取卵的数量和质量受年龄的影响,青年牛好于经产牛,经产牛好于老年牛;适量注射FSH 可以提高经产 牛和老年牛的囊胚率和(或) 平均囊胚数。

从线粒体Cyt b基因探讨红瘰疣螈物种地位的有效性

疣螈属的红瘰疣螈(Tylototriton shanjing)和棕黑疣螈(T.verrucosus)的物种界限一直不清楚.测定了来自中国西南地区14个地点的T.shanjing和T.verrucosus共40只标本的线粒体DNA Cyt b基因(753 bp).结果表明:(1)用邻接法、最大简约法和贝叶斯法等3种系统发育分析法分别重建棕黑疣螈种组系统发育树的拓扑结构不支持T.shanjing是单系群;(2)T.shanjing与T.verrucsus的mtDNA Cyt b序列差异平均值仅为1.2%.未达到种级水平.因此,全部T.shanjing样品都属于同一个物种,即T.verrucosus,不支持T.shanjing的物种地位,T.shanjing为T.verrucosus的同物异名,并建议恢复T.verrucosus的中文名红瘰疣螈.根据基于40个样品Cvt b基因序列的系统发育树和遗传变异以及地理分布,这些红瘰疣螈(T.verrucosus)样品聚为3支,即中国西南地区的红瘰疣螈可分为片马、滇中滇西和滇东南3个地理居群.

Molecular phylogeny and taxonomy of wood mice (genus Apodemus Kaup, 1829) based on complete mtDNA cytochrome b sequences, with emphasis on Chinese species

Phylogenetic relationships among 15 species of wood mice (genus Apodemus) were reconstructed to explore some long-standing taxonomic problems. The results provided support for the monophyly of the genus Apodemus, but could not reject the hypothesis of paraphyly for this genus. Our data divided the 15 species into four major groups: (1) the Sylvaemus group (A. sylvaticus, A. flavicollis, A. alpicola, and A. uralensis), (2) the Apodemus group (A. peninsulae, A. chevreri, A. agrarius, A. speciosus, A. draco, A. ilex, A. semotus, A. latronum, and A. mystacinus), (3) A. argenteus, and (4) A. gurkha. Our results also suggested that orestes should be a valid subspecies of A. draco rather than an independent species; in contrast, A. ilex from Yunnan may be regarded as a separate species rather than a synonym of orestes or draco. The species level status of A. latronum, tscherga as synonyms of A. uralensis, and A. chevrieri as a valid species and the closest sibling species of A. agrarius were further corroborated by our data. Applying a molecular clock with the divergences of Mus and Rattus set at 12 million years ago (Mya) as a calibration point, it was estimated that five old lineages (A. mystacinus and four major groups above) diverged in the late Miocene (7.82-12.74 Mya). Then the Apodemus group (excluding A. mystacinus) split into two subgroups: agrarius and draco, at about 7.17-9.95 Mya. Four species of the Sylvaemus group were estimated to diverge at about 2.92-5.21 Mya. The Hengduan Mountains Region was hypothesized to have played important roles in Apodemus evolutionary histories since the Pleistocene. (C) 2004 Elsevier Inc. All rights reserved.

Genetic relationship of Chinese and Japanese gamecocks revealed by mtDNA sequence variation

Cockfighting has a very long history dating back to as early as 2500 years ago in China. Cockfighting was intertwined with human cultural traditions, helped disperse chickens across the world, and influenced the subsequent breed selection. Therefore, trac

Matrilineal Components and Genetic Relationship of Silkies from China and Japan

Silkie is a famous black-bone chicken breed with beautiful silky feather. The unique medical property of this chicken was recorded in Chinese traditional medicine dictionary about 700 years ago. In this study, we analyzed the mtDNA D-loop sequence variation of 26 Bairong Silkies from Fujian Province, China, together with 100 reported Silkie mtDNAs from China and Japan, and studied their matrilineal components and genetic relationship. A total of 21 haplotypes were detected, which could be assigned to six haplogroups (A-E, G). Among them, haplogroups D and G were exclusively presented in Japanese Silkies and Chinese Silkies, respectively. Chinese Silkies had higher frequency of lineages belonging to haplogroups A, B, and E, and lower frequency of haplogroup C than Japanese Silkies. For the four Chinese Silkie populations, most of samples of Taihe, Chengdu, and Hubei Silkies were grouped in haplogroups A, B, and C, whereas most of Bairong Silkies were grouped in haplogroup E. Five haplotypes were shared by Japanese and Chinese Silkies. The genetic diversity of each Silkie population varied, but the overall diversity of Chinese Silkies was similar to that of Japanese Silkies. Taken together, our results confirmed the genetic connection between Chinese and Japanese Silkies, but also clearly showed that the matrilineal genetic structures of Chinese and Japanese Silkies had some differences.