[Toxicity Testing Organisms for Marine Ecotoxicological Research in China].

Since the late 1970s, marine ecotoxicology began to sprout and develop in China. Based on the principles of dose-response relationships, some marine organisms are used in toxicity tests to evaluate the impact of marine pollutants on marine organisms and marine ecosystems. At the early stage, marine ecotoxicological research mainly focused on the bioaccumulation, biomagnification, and biodegradation of traditional pollutants such as heavy metals, radioactive elements, organotin, petroleum hydrocarbons, and pesticides, as well as their toxic effects on survival, growth, and other physiological indicators. With the development of Chinese industry, marine pollution has become increasingly serious. In addition to the traditional marine pollutants, toxicological research has been conducted on emerging pollutants with potential risks to marine ecosystems, such as POPs, emerging organic pollutants, nanomaterials, and microplastics. Moreover, the species of marine organisms used in toxicity testing have become more diverse. The selection of testing organisms is essential for evaluating toxicity correctly. The toxicity tests should be conducted on a variety of organisms from different trophic levels to ensure the comprehensive understanding of the impact of pollutants on marine ecosystems. The major types of marine organisms used in the toxicity testing include marine alga, protozoa, rotifera, annelida, mollusc, echinoderma, arthropoda, cephalopoda, and marine fish, which have been used in the toxicological studies of various marine pollutants. The outcome results can serve as the scientific basis for the ecological risk assessment of marine pollutants and the establishment of seawater quality criteria. It should be noted that the sensitivity of different testing organisms to different types of pollutants is quite diverse. Therefore, in addition to conducting a battery of tests on a variety of species which play important roles in marine ecosystems, elucidating the toxic mechanisms in different species is also important for marine ecotoxicological studies. The application of the above-mentioned organisms in marine ecotoxicology research in recent years is briefly reviewed here. Particularly, the six commonly used marine model species (Skeletonema costatum, Euplotes vannus, oysters, sea urchins, Tigriopus japonicus, and Oryzias melastigma) used in toxicity testing are introduced in detail.

Dissecting the Neural Circuitry for Pain Modulation and Chronic Pain: Insights from Optogenetics / 神经科学通报·英文版

Pain is an unpleasant sensory and emotional experience associated with, or resembling that associated with, actual or potential tissue damage. The processing of pain involves complicated modulation at the levels of the periphery, spinal cord, and brain. The pathogenesis of chronic pain is still not fully understood, which makes the clinical treatment challenging. Optogenetics, which combines optical and genetic technologies, can precisely intervene in the activity of specific groups of neurons and elements of the related circuits. Taking advantage of optogenetics, researchers have achieved a body of new findings that shed light on the cellular and circuit mechanisms of pain transmission, pain modulation, and chronic pain both in the periphery and the central nervous system. In this review, we summarize recent findings in pain research using optogenetic approaches and discuss their significance in understanding the pathogenesis of chronic pain.

Role of tumor metastasis suppressor gene KAI1 in digestive tract carcinomas and cancer cells.

The KAI1 gene is identified as a tumor metastasis suppressor gene in many types of cancer. We examined KAI1 gene and its protein KAI1/CD82 expression by in situ hybridization and immunohistochemical analysis, and found that KAI1 mRNA and protein expression were inversely correlated with lymph node and distant metastasis in digestive tract carcinomas, but not with age and gender of the patient, or with tumor differentiation. Moreover, KAI1/CD82 protein expression positively reflected the survival outcome of patients. Western blot analysis showed that VP-16 increased KAI1/CD82 protein expression obviously in various cancer cell lines, especially in those that were highly metastatic. This increased KAI1/CD82 expression was associated with its translocation from the cytomembrane to the nucleus, in which it interacted with nuclear p53 protein, forming a strong complex, observed by confocal microscopy and co-immunoprecipitation, respectively. In nude mice, after feeding with VP-16, the number of tumors metastasized from spleen to liver was obviously reduced, and KAI1/CD82 protein expression became stronger in those metastatic tumors. Accordingly, this demonstrated that KAI1 might be used as an indicator for predicting the clinical outcome, and VP-16 may be clinically considered as a promising candidate for anti-metastasis with regard to its potential to upregulate KAI1 expression.