Prevalence of the methylenetetrahydrofolate reductase 677C>T polymorphism in the pregnant women of Yunnan Province, China.

Mutations in the methylenetetrahydrofolate reductase (MTHFR) gene can result in a reduced ability to utilize folic acid. The MTHFR 677C>T polymorphism in particular has been linked to both birth defects and pregnancy-associated diseases. This study aimed to evaluate the prevalence of the MTHFR 677C>T mutation among pregnant women in Yunnan Province so as to collect baseline data that may be utilized to guide folic acid supplementation efforts and to support related disease prevention programs. We retrospectively reviewed 3387 pregnant women from Yunnan Province. The MTHFR 677C>T polymorphism was identified using polymerase chain reaction (PCR) and DNA sequencing. In total, 1350 (39.9%) subjects were homozygous for the C allele (CC), 1540 (45.4%) subjects were heterozygous (CT), and 497 (14.7%) subjects were homozygous for the T allele (TT). The MTHFR 677C>T polymorphism was found to be present within the studied population, with ∼60% of these patients being either heterozygous or homozygous for the mutant allele and with an overall T allele frequency of 0.37. The frequency of the T allele was significantly higher among pregnant women with complications relative to women with healthy pregnancies, particularly among women <30 years old. As such, the maternal MTHFR 677C>T polymorphism may be a genetic risk factor associated with pregnancy complications and may help identify pregnant women at a high risk of such complications.

Antioxidant-related catalase CTA1 regulates development, aflatoxin biosynthesis, and virulence in pathogenic fungus Aspergillus flavus.

Reactive oxygen species (ROS) induce the synthesis of a myriad of secondary metabolites, including aflatoxins. It raises significant concern as it is a potent environmental contaminant. In Aspergillus flavus., antioxidant enzymes link ROS stress response with coordinated gene regulation of aflatoxin biosynthesis. In this study, we characterized the function of a core component of the antioxidant enzyme catalase (CTA1) of A. flavus. Firstly, we verified the presence of cta1 corresponding protein (CTA1) by Western blot analysis and mass-spectrometry based analysis. Then, the functional study revealed that the growth, sporulation and sclerotia formation significantly increased, while aflatoxins production and virulence were decreased in the cta1 deletion mutant as compared with the WT and complementary strains. Furthermore, the absence of the cta1 gene resulted in a significant rise in the intracellular ROS level, which in turn added to the oxidative stress level of cells. A further quantitative proteomics investigation hinted that in vivo, CTA1 might maintain the ROS level to facilitate the aflatoxin synthesis. All in all, the pleiotropic phenotype of A. flavus CTA1 deletion mutant revealed that the antioxidant system plays a crucial role in fungal development, aflatoxins biosynthesis and virulence.

Hypoxia off the Changjiang (Yangtze River) estuary and in the adjacent East China Sea: Quantitative approaches to estimating the tidal impact and nutrient regeneration.

Large areas of hypoxia have been reported off The Changjiang Estuary and in the East China Sea. Five cruises, covering winter, spring, and summer, were carried out from 2007 to 2013 in this region, and in August 2013 (summer), an extensive hypoxic event (11,150km2) was observed, which was characterized by an estimated bulk oxygen depletion of 5.1 million tons. A strong tidal impact was observed associated with the bottom oxygen depletion, with the periodicity of diel variations in dissolved oxygen being 12h (i.e., similar to the tidal cycle). A conservative estimate of nutrient regeneration suggested that during the hypoxic event of August 2013, the amount of regenerated nitrogen (as nitrate) and phosphorus (as dissolved inorganic phosphorus) was 27,000-30,000 tons and 1300-41,000tons, respectively. Estimates of the absolute (bulk) regenerated nutrient fluxes were much greater than the conservative estimates.

Antioxidant and antibacterial activity of six edible wild plants (Sonchus spp.) in China.

The total phenolic and flavonoid, antioxidant and antibacterial activities of six Sonchus wild vegetables (Sonchus oleraceus L., Sonchus arvensis L., Sonchus asper (L.) Hill., Sonchus uliginosus M.B., Sonchus brachyotus DC. and Sonchus lingianus Shih) in China were investigated. The results revealed that S. arvensis extract and S. oleraceus extract contained the highest amount of phenolic and flavonoid, respectively. Among the methanol extracts of six Sonchus species, S. arvensis extract exhibited the highest radical (DPPH and ABTS+ scavenging power and lipid peroxidation inhibitory power. It also exhibited the highest reducing power at 500 µg mL⁻¹ by A (700) = 0.80. The results of antibacterial test indicated that the S. oleraceus extract showed higher activity than the other five Sonchus wild vegetables extracts, both in Gram-negative bacteria (Escherichia coli, Salmonella enterica and Vibrio parahaemolyticus) and in a Gram-positive bacterium (Staphylococcus aureus). These results indicate that Sonchus wild food plants might be applicable in natural medicine and healthy food.