Reinstatement of Phyllanthus retroflexus Brade (Phyllanthaceae)

Phyllanthus retroflexus Brade is reinstated. It and the very similar P. subemarginatus Müll. Arg. are described, illustrated, and their relationships are discussed, based on a morphological analysis of herbarium specimens. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 78–81.     

Timing and plasticity of shoaling behaviour in the zebrafish, Danio rerio

The zebrafish has become a major model system for biomedical research and is an emerging model for the study of behaviour. While adult zebrafish express a visually mediated shoaling preference, the onset of shoaling behaviour and of this preference is unknown. To assess the onset of these behaviours, we first manipulated the early social environment of larval zebrafish subjects, giving them three model shoaling partners of the same pigment phenotype. We then assayed the subjects' preferences using binary preference tests in which we presented subjects with two shoals, one shoal of fish exhibiting the same pigment pattern phenotype as their models and another shoal with a radically different pigment pattern. To determine whether or not the visually mediated preference could be altered once it was established, we further manipulated the social environment of a number of subjects, rearing them with one model shoal and testing them, then changing their social consorts and retesting them. Our results demonstrate that larval zebrafish shoal early in their development, but do not exhibit a shoaling preference until they are juveniles. Moreover, we find that the shoaling preference is stable, as changing the social environment of fish after they had acquired a preference did not change their preference. These data will facilitate investigations into the mechanisms underlying social behaviour in this vertebrate model system.     

芒蛱蝶西藏一个新纪录及川藏地区黄缘蛱蝶的历史记录

在2017年6-7月对藏东南地区蝶类资源进行调查时,于墨脱县采集到了2枚芒蛱蝶Euripusnyctelius(鳞翅目:蛱蝶科)标本,经鉴定为西藏新纪种,同时也是首次在西藏发现芒蛱蝶属;于察隅县采集到1枚黄缘蛱蝶Nymphalisantiopa(鳞翅目:蛱蝶科),兹此列举诸多川藏地区黄缘蛱蝶的历史采集记录;并结合西藏处于古北区和东洋区生物交界带的地理位置,对在西藏发现两种蝴蝶的特殊意义进行了简要讨论。     

A novel gene delivery system targeting cells expressing VEGF receptors

Two ligand oligopeptides GV1 and GV2 were designed according to the putative binding region of VEGF to its receptors.GV1,GV2 and endosome releasing oligopeptide HA20 were conjugated with poly-L-lysine or protamine and the resulting conjugates could interact with DNA in a noncovalent bond to form a complex.Using pSV2-β-galactosidase as a reporter gene,it has been demonstrated that exogenous gene was transferred into bovine aortic arch-derived endothelial cells (ABAE) and human malignant melanoma cell lines (A375) in vitro.In vivo experiments,exogenous gene was transferred into tumor vascular endothelial cells and tumor cells of subcutaneously transplanted human colon cancer LOVO,human malignant melanoma A375 and human hepatoma graft in nude mice.This system could also target gene to intrahepatically transplanted human hepatoma injected via portal vein in nude mice.These results are correlated with the relevant receptors(flt-1,flk-1/KDR) expression on the targeted cells and tissues.     

Dispersed polyphosphate in fungal vacuoles in Eucalyptus pilularis/Pisolithus tinctorius ectomycorrhizas.

Ectomycorrhizas produced between Pisolithus tinctorius and Eucalyptus pilularis under axenic conditions were rapidly frozen, freeze-substituted in tetrahydrofuran and embedded anhydrously, and dry-sectioned for X-ray microanalysis. The vacuoles of the sheath and Hartig net hyphae were rich in phosphorus and potassium. They also contained sulfur and variable amounts of chlorine. In anhydrously processed freeze-substituted mycorrhizas, dispersed electron-opaque material filled the fungal vacuoles. X-ray maps indicated that P was distributed evenly throughout the entire vacuole profile and was not concentrated in spherical bodies or subregions of the vacuole. There were no electron-opaque granules surrounded by electron-lucent areas, such as are commonly seen in chemically fixed material. The fungal vacuoles were also rich in K, which similarly gave a signal from the entire vacuolar profile. Such P-rich vacuoles occurred in both the mycorrhizal sheath and Hartig net hyphae. Stained sections of ether-acrolein freeze-substituted mycorrhizas also showed only dispersed material in the fungal vacuoles as, in most cases, did acetone-osmium freeze-substituted material. Precipitation of metachromatic granules by ethanol suggested that large amounts of polyphosphate are stored in these regions under the conditions of our experiments, as well as in the tips of actively growing hyphae of the same fungus. The higher plant vacuoles of ectomycorrhizas gave a much lower signal for K, and P was barely detectable. Much more K was located in the vacuoles of the root exodermal cells than in epidermal cells. The analysis of element distribution between the vacuole and cytoplasm in root cells agrees well with that found for other plant species using other techniques. We conclude that polyphosphate is indeed present in the vacuoles of the fungal cells of these ectomycorrhizas, but that in vivo it is in a dispersed form, not in granules.