A Pilot Study on Neopterin Levels and Tryptophan Degradation in Zinc-Exposed Galvanization Workers

Hot-dip galvanization is a zinc-coating process to protect the metal items from corrosion. Zinc oxide nanoaerosol fume rising from hot metal bath surface in nano dimensions contains the greatest risk for workers in galvanization process. In the present study, it was evaluated whether inhalation of zinc causes any alteration in cellular immunity and tryptophan degradation by measuring neopterin, tryptophan, kynurenine, and zinc levels in 63 male galvanization workers and 23 male office personnel as controls. Serum and urinary zinc levels were found as 14.90?±?0.90 and 102?±?4.7 μg/dL in workers while 12.87?±?1.45 and 75?±?4.2 μg/dL in controls, respectively (both, p?<?0.05). Similarly, the mean urinary neopterin levels and serum neopterin and kynurenine levels were found to be statistically higher in galvanization workers than the controls (all, p?<?0.05). Significant correlations were found between urinary neopterin levels and kynurenine to tryptophan ratio or serum zinc levels. The results indicated cellular immune activation by occupational zinc exposure. It was estimated that neopterin, in parallel with kynurenine pathway, could reflect occupational exposure to zinc nanoaerosols and might be useful in early diagnosis of immune alterations due to nano-scale exposures.     

Genes involved in glucose repression and oxidative stress response in the fission yeast Schizosaccharomyces pombe

We looked for changes in gene expression and novel genes that could be involved in the interaction between glucose repression and oxidative stress response in the fission yeast, Schizosaccharomyces pombe, using a constitutive invertase mutant, ird11, which is resistant to glucose. BLAST analysis was made of the S. pombe genome database of cDNAs whose expression ratios differentially decreased or increased upon exposure to mild oxidative stress in this mutant compared to the wild type. Genes with this type of activity were identified as rpl302, encoding 60S ribosomal protein L3, and mpg1, encoding mannose-1-phosphate guanyltransferase; their expression patterns were measured using quantitative real-time PCR. We found that the expression levels of rpl302 and mpg1 genes in ird11 under unstressed conditions were increased compared to those of the wild type. Under stress conditions, the expression levels of the rpl302 gene were decreased in both strains, while mpg1 expression levels remained unchanged. These results suggest that these genes play a role in the response to oxidative stress in this mutant strain.     

Using spray-dried and encapsulated Nannochloropsis oculata biomasses in white spread

Journal of Applied Phycology - In this study, dried or encapsulated Nannochloropsis oculata microalgal biomass was used in spread samples (0.00–0.75&nbsp;g (100&nbsp;g)?1...     

Expression of human cytochrome p450 3A4 gene in Schizosaccharomyces pombe

Heterologous expression systems can be utilized to great advantage in the study of cytochrome P450 enzymes. P450 3A4 is one of the major forms of cytochrome P450 found in liver. It is also involved in the metabolism of numerous widely used drugs and xenobiotics. In the present study human liver cytochrome P450 3A4 gene was transferred into the fission yeast Schizosaccharomyces pombe via two different S. pombe expression vectors carrying thiamine repressible promoter — nmt1 (pREP42) and constitutive promoter — adh1 (pART1). Heterologously expressed cytochrome P450 3A4 was detected in the cells grown in minimal (EMM) or rich medium (YEL) containing 0.5% (w/v) glucose. A typical cytochrome P450 peak for 3A4 was observed at 448 nm in microsomal fraction. The presence of heterologous expression of 3A4 form was also determined by SDS-PAGE and it molecular mass was identified as 52 kDa. The enzyme activity was confirmed by HPLC analysis, using testosterone as substrate.