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This study aimed to construct a dose-response model of aflatoxin B1 (AFB1)-induced apoptosis rate in rat hepatocytes by using quantitative data. The coefficients of determination (R2) and further mathematical tests showed that the Gamma model (R2 = 0.996 4, Akaike information criterion = 37.40, and Bayesian information criterion = 17.19) was superior to other models. Hence, the Gamma model was recommended as the optimal dose-response model for apoptosis rate in rat hepatocytes after acute exposure to AFB1 for hazard characterization in the framework of AFB1 risk assessment.

Under the influence of the production process, fermented meat products are easily contaminated during processing and storage, posing safety risks and causing harms to human health. In this paper, the biological, chemical, physical and other hazardous factors of fermented meat products and the biological, chemical and physical control measures against these factors as well as their underlying mechanisms are systematically reviewed. Finally, the problems currently existing in the prevention and control of the harmful factors and follow-up research directions are discussed. Hopefully this review will provide a theoretical basis for the research and development of fermented meat products.

A new N-ethyl-N-nitrosourea (ENU)-induced mouse recessive mutation, identified by fundus examination of the eye, develops depigmented patches, indicating retinal disorder. Histology data show aberrant retinal pigment epithelium (RPE) and late-onset photoreceptor cell loss in the mutant retina. Chromosomal mapping and DNA sequencing reveal a point mutation (T to A) of the Slc9a8 gene, resulting in mutant sodium/proton exchanger 8 (NHE8)-M120K protein. The lysine substitution decreases the probability of forming the 3rd transmembrane helix, which impairs the pore structure of the Na+/H+ exchanger. Various RPE defects, including mislocalization of the apical marker ezrin, and disrupted apical microvilli and basal infoldings are observed in mutant mice. We have further generated NHE8 knockout mice and confirmed similar phenotypes, including abnormal RPE cells and late-onset photoreceptor cell loss. Both in vivo and in vitro data indicate that NHE8 co-localizes with ER, Golgi and intracellular vesicles in RPE cells. Thus, NHE8 function is necessary for the survival of photoreceptor cells and NHE8 is important for RPE cell polarity and function. Dysfunctional RPE may ultimately lead to photoreceptor cell death in the NHE8 mutants. Further studies will be needed to elucidate whether or not NHE8 regulates pH homeostasis in the protein secretory pathways of RPE.

Tyrosinase is a copper-containing oxidation enzyme, which is responsible for the production of melanin. This enzyme is widely distributed in microorganisms, animals and plants, and plays an essential role in undesirable browning of fruits and vegetables, antibiotic resistance, skin pigment formation, sclerotization of cuticle, neurodegeneration, etc. Hence, it has been recognized as a therapeutic target for the development of antibrowning agents, antibacterial agents, skin-whitening agents, insecticides, and other therapeutic agents. With great potential application in food, agricultural, cosmetic and pharmaceutical industries, a large number of synthetic tyrosinase inhibitors have been widely reported in recent years. In this review, we systematically summarized the advances of synthetic tyrosinase inhibitors in the literatures, including their inhibitory activity, cytotoxicity, structure-activity relationship (SAR), inhibition kinetics, and interaction mechanisms with the enzyme. The collected information is expected to provide a rational guidance and effective strategy to develop novel, potent and safe tyrosinase inhibitors for better practical applications in the future. [ABSTRACT FROM AUTHOR]