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Allophycocyanin (APC) is a minor component of phycobiliproteins in cyanobacteria and red algae. This paper describes a simple and inexpensive extracting method for isolating APC from Spirulina (Arthrospira) platensis with high efficiency. The crude phycobiliprotein extract was pretreated by ammonium sulfate fractionation. Then, by adding hydroxylapatite into crude phycobiliprotein extract dissolved in 20 mM phosphate buffer (pH 7.0), APC was selectively adsorbed by hydroxylapatite but C-phycocyanin (C-PC) was not. The hydroxylapatite was collected and APC was extracted from the crude phycobiliprotein extract. Then, the enriched APC was washed off from the hydroxylapatite using 100 mM phosphate buffer (pH 7.0). In this simple extracting method it was easy to remove C-PC and isolate APC in large amounts. The absorbance ratio A650/A280 of extracted APC reached 2.0. The recovery yield was 70%, representing 4.61 mg · g−1 wet weight. The extracted APC could be further purified by a simple anion-exchange chromatography with a pH gradient from 5.6 to 4.0. The absorbance ratio A650/A280 of the purified APC reached 5.0, and the overall recovery yield was 43%, representing 2.83 mg · g−1 wet weight. Its purity was confirmed by native polyacrylamide gel electrophoresis (PAGE) and sodium dodecyl sulfate-PAGE.

Currently, antioxidants are added in the human diet to prevent free radical-induced cell damage, and there has been an explosive interest in the use of antioxidant nutritional supplements. The effects of different factors on the antioxidant activity of phycocyanins (PCs) were studied. The results showed that PCs generated hydroxyl radicals in the light, while scavenging them in the dark. When PCs were denatured by sodium dodecyl sulfate, urea and in alkaline condition, their ability to generate hydroxyl radicals disappeared and that of scavenging them greatly increased. This showed that the phycobilin moiety is the main part of PC involved in scavenging hydroxyl radicals. Trypsin hydrolysis of PCs showed that the apoprotein portion of the molecule also made a significant contribution to the antioxidant activity.

Filaments from Grateloupia turuturu were obtained through germination of spores, regeneration from fragments of discoid crusts and erect thalli. The rates of filament formation through the three ways were 5.3 +/- 1.2%, 100%, and 62.3 +/- 5.6%, respectively. Discoid crusts were the best materials for the production of filaments. The obtained filaments were cloned in stationary and aerated culture. The differentiations of filaments were observed. When attached to the substrata, filaments differentiated into discoid crusts from which erect thalli grew, whereas for filaments in suspension culture, some cells in the filaments differentiated into spherical structures that also formed new erect thalli. Moreover, fragments of filaments (< 100 mu m) were seeded onto nori-nets. The regenerated plantlets grew into adult thalli in field cultivation.

Through implementing hierarchical management and monitor, improving and perfecting the hospital nurse training mechanism, implementing wages and labor outcomes in association with mechanism, further cultivating high-quality and high-level nursing management personnel, constantly improving quality, which maximize all the nursing staff 's enthusiasm and creativity, enhance the cohesion of nursing team, and improve the quality of hospital care.

On a examine le mode d'action de la 5-hydroxytryptamine (5HT) dans les petites arteres spinales anterieures isolees de chiens. De faibles concentrations (l0 -9 -10 -7 M) de 5HT ont provoque une contraction dose-dependante, alors que des concentrations plus elevees (10 -6 -10 -3 M) ont provoque une relaxation dose-dependante des arteres precontractees par 10 -7 M de U 46619. La relaxation induite par 5HT a ete significativement antagonisee par la methiothepine (10 -9 -10 (NR> M). La ketanserine (10 -6 M) et l'ICS 205-930 (3 x 10 -6 M) n'ont pas influe sur la relaxation des arteres par 5HT. La reponse relaxante a 5HT a ete significativement reduite par le frottement mecanique des cellules endotheliales. La relaxation independante de l'endothelium induite par 5HT a aussi ete antagonisee par la methiothepine (10 -6 M). L'aspirine (5 x 10 -5 M) ou le N ω -nitro-L-arginine methyl ester (L-NAME) (10 -6 M) ont supprime significativement la relaxation dependante de l'endothelium induite par 5HT. La L-arginine (10 -3 M) a aussi renverse significativement la reduction induite par L-NAME de la relaxation dependante de l'endothelium induite par 5HT. De plus le traitement par L-NAME en presence d'aspirine a provoque une reduction beaucoup plus forte de la relaxation dependante de l'endothelium induite par 5HT. L'isocarbacycline (10 -9 -10 -5 M) a induit une relaxation dependante de la concentration des petites arteres spinales isolees, precontractees par 10 -7 M de U 46619. Ces resultats suggerent que la 5HT induit des relaxations independantes et dependantes de l'endothelium des petites arteres spinales anterieures isolees, principalement par le biais de l'activation du recepteur de type 5HT 1 , et que l'oxyde nitrique endogene et les prostaglandines vasodilatatrices pourraient participer a leur relaxation dependante de l'endothelium induite par 5HT.

In this study, the acute toxicity of butyl benzyl phthalate (BBP) to freshwater cladoceran Moina macrocopa was tested, and its chronic effects on survival and reproduction of two successive generations of the cladoceran were studied using life-table demographic method. The results showed that the 48-hr LC50 of BBP for M. macrocopa was 3.69 mg l(-1). Compared to the blank controls, BBP at 125, 500, 1000 and 2000 microg l(-1) significantly shortened the life expectancy at birth, BBP at 125-2000 microg l(-1) decreased the net reproductive rate, and BBP at 500 and 1000 microg I(-1) shortened the generation time but increased the intrinsic rate of population increase of the parental M. macrocopa. BBP at 62.5,125, 500,1000 and 2000 microg l(-1) increased the intrinsic rate of population increase of the F1 generation. A significant dose-effect relationship existed between BBP concentration and life expectancy at birth, net reproductive rate as well as intrinsic rate of population increase of the parental M. macrocopa. The parental M. macrocopa were more sensitive in survival, development and reproduction to BBP than the F1 generation, but the reverse was also true in the population growth. Extending chronic toxicity tests to the second generation of M. macrocopa increased the cost-effectiveness of the assays.

Spatio-temporal patterns and processes of genetic differentiation in passively dispersing zooplankton are drawing much attention from both ecologists and evolutionary biologists. Two opposite phylogeographical scenarios have already been demonstrated in rotifers, which consist of high levels of genetic differentiation among populations even on small geographical scales on the one hand and the traditionally known cosmopolitanism that is associated with high levels of gene flow and long-distance dispersal via diapausing stages on the other hand. Here, we analysed the population genetic structure and the phylogeography of the Brachionus calyciflorus species complex in eastern China. By screening a total of 318 individuals from ten locations along a 2320-km gradient and analysing samples from two growing seasons, we aimed at focusing on both small- and large-scale patterns. We identified eight cryptic species and verified species status of two of these by sexual reproduction tests. Samples in summer and winter yielded different cryptic species. The distribution patterns of these genetically distinct cryptic species were diverse across eastern China, from full cosmopolitanism to local endemism. The two most abundant cryptic species BcWIII and BcSW showed a pattern of strong genetic differentiation among populations and no significant isolation by distance. Long-distance colonization, secondary contact and recent range expansion are probably responsible for the indistinct pattern of isolation by distance. Our results suggest that geographical distance is more important than temporal segregation across seasons in explaining population differentiation and the occurrence of cryptic species. We explain the current phylogeographical structure in the B. calyciflorus species complex by a combination of recent population expansion, restricted gene flow, priority effects and long-distance colonization.

Elucidating the evolutionary patterns and processes of extant species is an important objective of any research program that seeks to understand population divergence and, ultimately, speciation. The island-like nature and temporal fluctuation of limnetic habitats create opportunities for genetic differentiation in rotifers through space and time. To gain further understanding of spatio-temporal patterns of genetic differentiation in rotifers other than the well-studied Brachionus plicatilis complex in brackish water, a total of 318 nrDNA ITS sequences from the B. calyciflorus complex in freshwater were analysed using phylogenetic and phylogeographic methods. DNA taxonomy conducted by both the sequence divergence and the GMYC model suggested the occurrence of six potential cryptic species, supported also by reproductive isolation among the tested lineages. The significant genetic differentiation and non-significant correlation between geographic and genetic distances existed in the most abundant cryptic species, BcI-W and Bc-SW. The large proportion of genetic variability for cryptic species Bc-SW was due to differences between sampling localities within seasons, rather than between different seasons. Nested Clade Analysis suggested allopatric or past fragmentation, contiguous range expansion and long-distance colonization possibly coupled with subsequent fragmentation as the probable main forces shaping the present-day phylogeographic structure of the B. calyciflorus species complex.

The 48 h LC50 of DDT to Moina macrocopa was determined by acute toxicity test, and the effects of different concentrations (1, 8, 16, 24, 32 and 40 microg x L(-1)) of DDT on the life table demography of M. macrocopa was studied by life table demography. The results showed that the 48 h LC50 of DDT to M. macrocopa was 324 microg x L(-1). 1-40 microg x L(-1) of DDT had no significant effects on the life expectancy at birth, generation time, net reproductive rate, and gross productive rate of M. macrocopa (P0.05), but significantly affected the intrinsic rate of population increase (rm) (P0.05). The rm of M. macrocopa increased markedly at 8, 16 and 40 microg x L(-1) of DDT, compared with the blank control, indicating that when the life table demography of M. macrocopa was used to monitor the ecological effects of sublethal concentrations of DDT, rm could be a sensitive indicator.

Through implementing hierarchical management and monitor, improving and perfecting the hospital nurse training mechanism, implementing wages and labor outcomes in association with mechanism, further cultivating high-quality and high-level nursing management personnel, constantly improving quality, which maximize all the nursing staff 's enthusiasm and creativity, enhance the cohesion of nursing team, and improve the quality of hospital care.