Analysis of Subject Related Costs in Medical Research / 中国医学伦理学

The development of medical research is completed by the cooperation of sponsors, investigators, subjects, and ethics committees. Clinically, it mainly includes clinical trials of medical devices, clinical medicine and new technology research. This paper analyzed the game and the relationship between rights, responsibilities and interests of relevant parties in medical research, combined with the relevant costs and sharing principles involved in medical research, and found that the use of the word "free" in the informed consent is easy to cause misunderstanding and the lack of relevant compensation costs in the informed consent, while the compensation and insurance costs had some problems, such as the imperfect subject compensation mechanism and the insufficient insurance purchase by the sponsor, which can not protect the basic rights and interests of the subjects. Therefore, in order to standardize the cost management of clinical medical research, it is necessary to standardize the process and content of informed consent, strengthen the supervision of medical research process, establish medical research damage compensation fund and research damage insurance system, so as to better protect the rights and interests of subjects.

Ethical Analysis of the Medical Science Experiments Targeting Humans / 中国医学伦理学

With the continuous progress of medical technology, some violations of ethical principles often occur in science experimental research targeting humans. Taking the type of human experimental research as the starting point, through ethical analysis and evaluation of different types of human experimental research, this paper concluded that in human experimental research, it was necessary to adhere to humanitarian principles of human experimental research, fully respect the research participants’ right to informed consent, select research participants fairly, fully protect the research participants’ rights and interests, and supervise the whole research process. So as to better regulate the behavior of medical researchers in human experimental research and protect the rights and interests of research participants.

Changes of m6A modification in arsenic-induced oxidative stress of human embryonic lung fibroblasts / 环境与职业医学

Background Arsenic can be toxic to human by triggering oxidative stress, which is companied by epigenetic modifications. Objective To investigate the modification of N6-methyladenosine (m6A) in human embryonic lung fibroblasts (HELF) during oxidative stress induced by sodium arsenite (NaAsO2). Methods HELF cells were treated by designed concentrations of NaAsO2 (0, 2.5, 5, 10, and 20 μmol·L−1) for 48 h. Cell viability was detected by 3-(4,5-dimethylthia zol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfopheny)-2H-tetrazolium (MTS) method; the activities of total superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-Px) as well as the content of malondialdehyde (MDA) were detected with corresponding kits; the level of m6A methylation in total RNA was detected by enzyme-linked immunosorbent assay; the mRNA expressions of m6A modified enzymes were detected by real-time fluorescence quantitative PCR, including methyltransferase-like 3 (METTL3), methyltransferase-like 14 (METTL14), Wilms' tumor 1-associated protein (WTAP), fat mass and obesity-associated protein (FTO), alkB family of Fe(II)/α-ketoglutarate-dependent dioxygenases 5 (ALKBH5), YTH domain containing protein 2 (YTHDC2), YTH domain family protein 2 (YTHDF2), and YTH domain family protein 3 (YTHDF3); the protein expressions of METTL3, FTO, YTHDC2, YTHDF3, and nuclear factor erythroid 2-related factor 2 (NRF2) were detected by Western blotting. The enrichment of m6A in NRF2 mRNA was detected by RNA methylated immunoprecipitation combined with real-time fluorescence quantitative PCR (MeRIP-qPCR). Results After the 0, 2.5, 5, 10, and 20 μmol·L−1 NaAsO2 treatment, the MTS results showed that compared with the control group, the cell viability of the 20 μmol·L−1 group decreased to 84% (P<0.05). The colorimetry results showed that compared with the control group, the activities of T-SOD in the 10 and 20 μmol·L−1 groups decreased (P<0.05); the activities of GSH-Px in the 2.5 and 10 μmol·L−1 groups decreased (P<0.05); the contents of MDA in the 10 and 20 μmol·L−1 groups increased. The results of enzyme-linked immunosorbent assay showed that the overall m6A methylation levels in the 0, 2.5, 5, 10, and 20 μmol·L−1 groups were (0.193 ± 0.023)%, (0.247 ± 0.021)%, (0.253 ± 0.006)%, (0.233 ± 0.006)%, and (0.262 ± 0.010)%, respectively, and compared with the control group, the m6A methylation levels in all the NaAsO2 treated groups increased (P<0.05). The real-time fluorescence quantitative PCR results showed that compared with the control group, the mRNA relative expression level of METTL3 decreased in the 2.5, 10, and 20 μmol·L−1 groups (P<0.05); the mRNA relative expression level of FTO decreased in the 20 μmol·L−1 group; the mRNA relative expression level of YTHDC2 increased in the 10 and 20 μmol·L−1 groups (P<0.05); the mRNA relative expression level of YTHDF3 increased in the 2.5, 10, and 20 μmol·L−1 groups (P<0.05). The Western blotting results showed that compared with the control group, the relative protein expression of METTL3 decreased in the 10 and 20 μmol·L−1 groups; the relative protein expression of FTO decreased in the 5 and 20 μmol·L−1 groups; the relative protein expression of YTHDC2 decreased in the 20 μmol·L−1 group (P<0.05); the relative nuclear protein expression of NRF2 decreased in the 10 and 20 μmol·L−1 groups (P<0.05). The MeRIP-qPCR results showed that m6A enrichment was significantly increased in the 20 μmol·L−1 NaAsO2 exposure group compared with the control group (P<0.05). After over-expression of FTO, the mRNA and protein relative expression levels of FTO and the relative expression level of nuclear protein of NRF2 in the FTO group were higher than those in the control group (P<0.05); the mRNA and protein relative expression levels of FTO in the NaAsO2 + FTO group and the nuclear protein expression level of NRF2 were higher than those in the NaAsO2 group (P<0.05). Conclusion In the process of oxidative stress induced by NaAsO2, m6A methylation level, m6A modified enzymes, m6A modification of NRF2 mRNA, and NRF2 expression could change in HELF cells.

Preparation of superparamagnetic paclitaxel nanoparticles from modified chitosan and their cytotoxicity against malignant brain glioma / 生物医学工程学杂志

We synthesized the superparamagnetic paclitaxel nanoparticles from modified chitosan tangling around Fe3O4 ferrofluid and taxol, and observed the nanoparticles with transmission electronic microscopy (TEM). Then we evaluated the paramagnetism of the particles by vibration specimen magnetometer (VSM) and tested their cytotoxicity with flow cytometry (FCM). The prepared nanoparticle solution was black without any floccule or sediment and appeared transparent after diluted. The nanoparticles were spherical and dispersed in water with mean diameter of 15 nm under TEM and showed superparamagnetic character. FCM test showed the nanoparticles had significant toxic effects against malignant astrocytoma U251 cell lines, equal to taxol alone. These results showed that the superparamagnetic nanoparticle not only enhanced the solubility of paclitaxel in water, but also was superparamagnetic and cytotoxic, which make suitable tools for magnetic targeting chemotherapy of brain gliomas.

Differential effects of early environmental enrichment on spatial learning and memory of wild house mouse and Kunming mouse / 中华行为医学与脑科学杂志

Objective To evaluate and compare the effect of early environmental enrichment on spatial learning and memory in wild house mouse and Kunming mouse,one kind of laboratory mouse which evolved from wild house mouse.Methods The wild house mouse F1 generation were employed to control the environmental enrichment.Offspring were weaned on PND22 and housed in usual or rich environment for one month randomly,then engaged the morris maze:house moutse rich environment(n=7),house mouse poor environment(n=6),Kunming mouse rich environment(n=10),Kunming mouse poor environment(n=10).Results (1)Early environmental enrichment improve the performance of house mouse(poor environment:(39.5±3.8)s;rich environment:(25.2±4.5)s;F(1,22)=8.115,P<0.01),but had no effect on that of Kunming mouse in tests of spatial memory (poor environment:(8.5±2.4)s;rich environment:(7.5±1.7)s;F(1,36)=0.149,P=0.702).(2)Early environmental enrichment improve the performance of house mouse(F(1,132)=15.307,P<0.01)and Kunming mouse (F(1,216)=8.701,P<0.01)in spatial learn session.Conclusion The wild house mouse is more sensitive to the enrich environment than laboratory mouse.Therefore,it has higher validity of model.