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Yeast single-cell protein (SCP) is a high-nutrient feed substitute. This study evaluates the dual applications of a novel recombinant Pichia pastoris SMD1168H (SMD) yeast, expressing a tilapia vitellogenin protein (rVtg), as an SCP diet for Artemia and the first-feeding fish larvae. Instar II Artemia fed rVtg, rVtg precultured in 5% fish oil (rVtg-FO), Saccharomyces cerevisiae (SC), or native SMD had greater lipid contents (P < 0.05) than the freshly hatched. Lipid deposition in the Artemia fed rVtg or rVtg-FO was greater (P < 0.05) than in those fed SMD or SC. Diet-induced accumulation of low levels of docosahexaenoic acid [22:6(n-3)] was detected only in Artemia fed the rVtg-based diets. Tilapia (Qreochromis mossambicus) larvae were fed solely yeast diets singly or in combination (d 3-22), or a staggered regimen of yeast (d 3-12) followed by unenriched or yeast-enriched Artemia (d 13-22). The larvae fed rVtg for 22 d increased in length and weight (P < 0.05), whereas those fed SC or SMD suffered growth suppression and high mortality. Such adverse consequences were ameliorated when 50% of SC was substituted with rVtg. The larvae prefed rVtg followed by a dietary switch to Artemia preenriched for 48 h with rVtg or rVtg-FO were greatest in length, had the highest weight gain, and lived the longest. Besides delivering rVtg protein, essential fatty acids and amino acids, rVtg may have probiotic effects in enhancing larval survival. This study suggests the feasibility of using the rVtg yeast as an Artemia booster and an SCP first feed for larvae. KEY WORDS: * yeast recombinant vitellogenin * Artemia enrichment * live yeast-feed for fish larvae * larval growth and survival

Background Vitiligo is an acquired depigmentation disorder of melanocytes. Recently, some clinical reports have suggested that proton pump inhibitors ( PPIs) may worsen vitiligo, but their effects on melanocytes have yet to be elucidated. Objective We investigated the effect of PPIs on melanogenesis in vivo and in vitro. Methods We examined the effect of PPIs on melanogenesis in B16 murine melanoma cells by measuring melanin content and tyrosinase ( TYR) activity. TYR and tyrosinase-related protein-1 ( TRP-1) were monitored by western blotting. Finally, a PPI was applied to zebrafish embryos to investigate its in vivo effect on pigmentation. Results In agreement with our clinical experience of worsened vitiligo after PPI treatment, PPIs decreased both melanin content and TYR activity. Western blotting showed that PPIs decreased TYR and TRP-1 protein levels. In the zebrafish test, PPIs inhibited body pigmentation in a dose-dependent manner. Conclusion These results suggest that the functional inhibition of melanization by PPIs may induce or aggravate vitiligo lesions in genetically predisposed patients. [ABSTRACT FROM AUTHOR]

Cobalt silicide formation has been shown to be improved by a reactive Ti capping layer. We investigated the effects of the first rapid thermal anneal (RTA1) temperature on the silicidation mechanism and CoSi2 film properties. It was found that a higher RTA1 temperature results in lower sheet resistance, a smoother CoSi2/Si interface and better film thermal stability. The improved thermal stability may be explained by the smoother CoSi2/Si interface at higher RTA1 temperature. [Copyright &y& Elsevier]