Microplastics (MPs) are currently a global environmental pollutants and health hazards that caused by MPs cannot be ignored. However, studies on MP toxicity in mammals are scare. Here, we investigated the effects of two doses (0.1 mg and 0.5 mg) of 5 µm polystyrene microplastic (PS-MP) particles on the hematological system of mice through traditional toxicology experiments and assessed the related potential biological mechanisms using transcriptome sequencing analysis. The toxicological examinations showed that the 0.5 mg dose significantly decreased white blood cell count, increased Pit count, and inhibited the growth of colony-forming unit CFU-G, CFU-M and CFU-GM. Compared with the control group, there were 41 differentially expressed genes (DEGs) in the 0.1 mg-treated group and 32 significantly changed genes in 0.5 mg-treated group. Of note, eight genes were found to be significantly altered in both the PS-MP-treated groups. Gene ontology analysis showed that DEGs were mainly involved in T cell homeostasis, response to osmotic stress, extracellular matrix and structure organization, and metabolic process of NADP and nucleotides. In addition, pathway analysis revealed that the Jak/Stat pathway, pentose and glucuronate interconversions, nicotinate and nicotinamide metabolism, biosynthesis of unsaturated fatty acids, and the pentose phosphate pathway were involved in PS-MP-induced toxicity in mice. These results indicated that PS-MP exposure can cause hematotoxicity to some extent, impact gene expression, and disturb related molecular and biological pathways in mouse bone marrow cells. Our study provides fundamental data on the hematotoxicity of PS-MPs in terrestrial mammals that will help to further assess the corresponding health risks in these mammals.
Team-based learning (TBL) has been adopted as a new medical pedagogical approach in China. However, there are no studies or reviews summarizing the effectiveness of TBL on medical education. This study aims to obtain an overall estimation of the effectiveness of TBL on outcomes of theoretical teaching of medical education in China. We retrieved the studies from inception through December, 2015. Chinese National Knowledge Infrastructure, Chinese Biomedical Literature Database, Chinese Wanfang Database, Chinese Scientific Journal Database, PubMed, EMBASE and Cochrane Database were searched. The quality of included studies was assessed by the Newcastle-Ottawa scale. Standardized mean difference (SMD) was applied for the estimation of the pooled effects. Heterogeneity assumption was detected by I2 statistics, and was further explored by meta-regression analysis. A total of 13 articles including 1545 participants eventually entered into the meta-analysis. The quality scores of these studies ranged from 6 to 10. Altogether, TBL significantly increased students’ theoretical examination scores when compared with lecture-based learning (LBL) (SMD = 2.46, 95% CI: 1.53–3.40). Additionally, TBL significantly increased students’ learning attitude (SMD = 3.23, 95% CI: 2.27–4.20), and learning skill (SMD = 2.70, 95% CI: 1.33–4.07). The meta-regression results showed that randomization, education classification and gender diversity were the factors that caused heterogeneity. TBL in theoretical teaching of medical education seems to be more effective than LBL in improving the knowledge, attitude and skill of students in China, providing evidence for the implement of TBL in medical education in China. The medical schools should implement TBL with the consideration on the practical teaching situations such as students’ education level.
1 February 2020 in Science of The Total Environment