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Primordial germ cells (PGCs) appear during early embryogenesis and differentiate into gametes through oogenesis or spermatogenesis. Teleost PGCs can be visualized by injecting RNA transcribed from the fusion product of a fluorescent protein gene attached to the 3' untranslated region (3'UTR) of zebrafish nanos3 (zf-nos3). Although this method has been widely applied to teleost PGCs, the visualization of PGCs in pelagic species that have eggs with a hard chorion is more problematic due to the technical difficulty of microinjection into their eggs. In this study, we developed a reliable method for microinjection of fertilized eggs in a pelagic species, the barfin flounder. Using a microneedle with a constriction "brake", we were able to introduce gfp-nos3 3'UTR mRNA into embryos and to determine the origin and migration route of PGCs. We also isolated the barfin flounder nos3 (bf-nos3) gene to compare its 3'UTR sequence with that of zebrafish. The 3'UTR of the bf-nos3 sequence was longer than that of zf-nos3. However, PGCs were also visualized after injection of gfp-bf-nos3 3'UTR mRNA both in zebrafish and barfin flounder. These results suggest that the function of nos3 is conserved between these species regardless of the sequence differences. The method developed here for labeling PGCs with gfp-nos3 mRNA will provide a means to study PGC development in the embryos of a wide range of marine fish species. [ABSTRACT FROM AUTHOR]

A carbohydrate other than sucrose, glucose, fructose and myo‐inositol was detected in sepal extracts of Delphinium. This compound was identified as mannitol by 1H‐NMR. Mannitol was the major carbohydrate in all examined organs: the sepal, the other parts of the flower, the stem and leaves. Mannitol as well as glucose (both at 0.55 M), fed to cut Delphinium flowers, similarly delayed the abscission of sepals. 3‐O‐methyl glucose (3‐OMG) and polyethylene glycol 200 at the same molar concentrations had no such effect. The treatment with glucose markedly increased the concentrations of glucose and fructose in the sepals without changing the concentrations of sucrose and mannitol. On the other hand, the treatment with mannitol increased the concentrations of glucose and fructose in addition to mannitol in the sepals, suggesting that mannitol is metabolized in Delphinium flowers. The treatment with 3‐OMG increased the concentration of 3‐OMG but not other carbohydrates. Mannitol and glucose similarly delayed the increase in ethylene production in flowers, but 3‐OMG did not. The sensitivity to ethylene was similarly reduced by the treatment with glucose and mannitol, but not by 3‐OMG. These results suggest that the treatment with mannitol, a major carbohydrate in Delphinium, delayed the abscission of sepals by reducing the sensitivity to ethylene. Mannitol further acted, not merely as an osmolyte, but as an apparent source for carbohydrate metabolism in the flower. [ABSTRACT FROM AUTHOR]

The article presents a systematic review and meta-analysis of randomised controlled trials as of mid-April 2014 to examine the effect of antibiotics on the growth of children in low and middle income countries. It claims that antibiotics are recommended by the World Health Organization to treat severely malnourished children and those infected or exposed to HIV. In the study, data from Medline, Embase, Scopus and the Cochrane central registers were examined.