Ultrastructural characters of a Physarum melleum on living leaves of Dendrobium candidum in China / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

A known species, Physarum melleum, was found fruiting on living leaves of Dendrobium candidum, which was collected in China in 2004. Its morphological characters were revealed by light microscopy (LM), environmental scanning electron microscopy (ESEM) and scanning electron microscopy (SEM). Character variations were distinguished by its olive-yellow peridium and its always thinner capillitium containing globulose granular material between the large calcareous nodes. The calcium carbonate granules, deposited on stalks, peridium and hypothallus as well as within stalks, were globose and smooth.

Investigation of the sterol composition in the molluscan snails biomphalaria Alexandria, lymnaea truncatula and physa acuta

Sterol fractions were isolated from the hemolymph and hepatopancreasovotestis complex of snails, target [Biomphalaria alexandrina] and non- target [Lymnaea truncatula and Physa acuta] to schistosoma infection. The sterol fractions were identified using GC/MS and also they were investigated in different maturity stages of Biomphalaria alexandrina snails. The results revealed the presence of C[26], C[27], C[28], C[29], and C[30] sterols in tissue extracts and hemolymph or hemocyanin of the three snail species. The probable biosynthetic pathways and metabolism of some of these sterols into various forms present in higher vertebrates were discussed. It is suggested that Biomphalaria alexandrina snails are capable of converting delta[5] sterols into- delta[7] and delta[5,7,22] sterols. Also, the different maturity stages of B. alexandrina snails revealed the possible role of the digestive gland in the interconversion of sterols and the increase in sterol content with sexual maturity. Sterol fractions were investigated by GC/MS from hemolymph and hepatopancreas-ovotestis complex of Schistosoma target [B. alexandrina] and Schistosoma non-target [Lymnaea truncatula and Physa acuta] snails. Also the levels of these sterols were determined in different maturity stages [juvenile, adult, sensent] of B. alexandrina snails

Synergistic effect of heat-shock and UV-irradiation on mitosis and protein synthesis in G2-phase plasmodia of Physarum polycephalum Schw--reduction in UV-induced mitotic delay in a preheat-shocked system.

The synergistic effect of UV irradiation and heat-shock during the last 3 hr of G2 phase of the cell cycle in the plasmodia of P. polycephalum, in terms of mitotic delay and inhibition of protein synthesis, has been evaluated. The mitotic delay due to both perturbers coordinately increased closer to mitosis. Maximum mitotic delay was obtained in plasmodia heat-shocked after UV irradiation, indicating the presence in this system of either a heat-labile mitogenic substance which is comparatively less susceptible to UV or a substance which is made more susceptible to hyperthermia by UV. A protective role for heat-shock applied before irradiation has been observed in that, radiation-induced mitotic delay is significantly reduced in this combination. There was severe inhibition of translation in all the perturbed classes. Organelle level effects which are independent of major protein synthetic activities or different levels of heat-shock protein production could be the reason for the lack of correlation between percentage inhibition of general protein synthesis and the extent of mitotic delay with respect to the two double-perturbed systems.