Design, synthesis, and activity study of α-conotoxin A10LPnIA fluorescent probe / 药学学报

italic>α7 nicotinic acetylcholine receptor (nAChR) is widely distributed in the central and peripheral nervous systems, and is closely related to a variety of neurological diseases and inflammation response. α-Conotoxin [A10L]PnIA, as an antagonist targeting α7 nAChR, plays an important role in studying the physiological and pathological processes involved in α7 nAChR. [A10L]PnIA was labeled with fluorescein 5-carboxytetramethylrhodamine, and the active peptide ([A10L]PnIA-F) was obtained by a two-step oxidative folding procedure in vitro. The Xenopus oocyte expression system and the two-electrode voltage clamp technique were used to identify the potency of [A10L]PnIA-F fluorescent peptide, and its cytotoxicity was detected by mouse macrophages and CCK8 method. The molecular weight of [A10L]PnIA-F fluorescent peptide was identified by mass spectrometry as 2 077.28 Da, which was consistent with the theoretical value. Electrophysiological determination of its half-maximal inhibitory concentration (IC50) for α7 nAChR is 17.32 nmol·L-1, which is consistent with [A10L]PnIA (IC50, 13.84 nmol·L-1). The cytotoxicity test results showed that within the concentration range of 5 nmol·L-1 to 10 μmol·L-1, there was no significant inhibition on the growth of mouse macrophages. The results showed that the α-conotoxin fluorescent probe [A10L]PnIA could provide pharmacological tools for the research of α7 nAChR-related neurophysiological and pathological mechanisms.

Expression of Twist1, SIRT1, FGF2 and TGF-β3 genes and its regulatory effect on the proliferation of placenta, umbilical cord and dental pulp mesenchymal stem cells / 中华医学遗传学杂志

OBJECTIVE@#To compare the mRNA level of cell proliferation-related genes Twist1, SIRT1, FGF2 and TGF-β3 in placenta mesenchymal stem cells (PA-MSCs), umbilical cord mensenchymals (UC-MSCs) and dental pulp mesenchymal stem cells (DP-MSCs).@*METHODS@#The morphology of various passages of PA-MSCs, UC-MSCs and DP-MSCs were observed by microscopy. Proliferation and promoting ability of the three cell lines were detected with the MTT method. Real-time PCR (RT-PCR) was used to determine the mRNA levels of Twist1, SIRT1, FGF2, TGF-β3.@*RESULTS@#The morphology of UC-MSCs and DP-MSCs was different from that of PA-MSCs. Proliferation ability and promoting ability of the PA-MSCs was superior to that of UC-MSCs and DP-MSCs. In PA-MSCs, expression level of Twist1 and TGF-β3 was the highest and FGF2 was the lowest. SIRT1 was highly expressed in UC-MSCs. With the cell subcultured, different expression levels of Twist1, SIRT1, FGF2, TGF-β3 was observed in PA-MSCs, UC-MSCs and DP-MSCs.@*CONCLUSION@#Up-regulated expression of the Twist1, SIRT1 and TGF-β3 genes can promote proliferation of PA-MSCs, UC-MSCs and DP-MSCs, whilst TGF-β3 may inhibit these. The regulatory effect of Twist1, SIRT1, FGF2 and TGF-β3 genes on PA-MSCs, UC-MSCs and DP-MSCs are different.

Prevalence and associated factors of seeking casual male sexual partners among men who have sex with men students in Guangzhou / 中国学校卫生

Objective@#To examine the prevalence and associated factors of seeking casual male sexual partners among men who have sex with men (MSM) students in Guangzhou, and to provide a reference for health education and intervention.@*Methods@#A cross-sectional study was conducted to recruit 189 MSM students aged 18 and 28 via voluntary counseling and testing (VCT) clinics, Lingnan partners and Zhitong charity from May 2017 to April 2018. An anonymous electronic questionnaire was administrated to collect information on sociodemographic and sexual behavior characteristics. Chi-square test and non-conditional Logistic regression analysis were performed to explore the associated factors of casual homosexual behavior among MSM students.@*Results@#In the past 6 months, 63.49% (120/189) of them reported casual male partners, and the rate of consistent condom use was 61.67%(74/120). Multivariate Logistic regression analysis showed that participants who had multiple sex partners in the past 6 months were more likely to seek male casual partners(aOR=9.13, 95%CI=4.27-19.53). Individuals who used recreational drugs before sex were at a higher risk of having casual sex behaviors(aOR=3.06, 95%CI=1.08-8.62). MSM students who had steady homosexual partners had a lower risk to seek casual sex(aOR=0.43, 95%CI=0.19-0.98).@*Conclusion@#The proportion of seeking casual male sexual partners among MSM students in Guangzhou was relatively high. The publicity and education should be strengthened among those who had multiple sex partners, with no steady homosexual partners and used recreational drugs before sex, to reduce the casual sex behaviors.

Analysis of the attitude and behavior in research of the stomatological professional postgraduates / 中华医学科研管理杂志

Objective:To explore the attitude and behavior of scientific research in professional postgraduates majoring in stomatology in Peking University, proposing suggestions to improve the quality of scientific research training.Methods:150 professional postgraduates of stomatology including the 8-year program stomatological students (the postgraduate stage) of Peking University School of Stomatology were involved in the survey, information including the types of and attitudes to scientific research, the evaluation of research environments, the understanding of the relationship with their mentors, and the expected working institutions after graduation was collected by questionnaires.Results:A total number of 131 valid questionnaires were collected, with an effective rate of 87.3%. In terms of the type of research work, 70 (53.4%) were engaged in basic research and 30 (22.9%) in clinical research. In terms of attitudes towards scientific research training, 69 (52.7%) respondents agreed that scientific research and clinical practice promoted each other. The Likert scores of scientific research interest, ability, and pressure were 3.13 ± 0.84, 3.04 ± 0.84, and 4.14±0.71. The evaluation of laboratory conditions (3.30±0.92), scientific research funding (3.54±1.06), scientific research atmosphere (3.89±0.85), and reward and punishment mechanisms (3.82±0.76) were positive. The evaluations of scientific research training courses (2.89±0.88) and scientific training time (2.79±0.94) were negative. The average score of the rapport level between postgraduates and their mentors was 4.29±0.77, and 111 respondents (84.7%) had a correct understanding of the guiding relationship. Sixty-six respondents (50.4%) expected to engage in clinical and scientific research in stomatological schools and 61 (46.6%) expected to engage in clinical work only, after graduation.Conclusions:The scientific research for graduate students of stomatology in Peking University is mainly basic research, and the research pressure is relatively high. It is recommended to choose research topics in combination with clinical practice, clarify the significance of scientific research, optimize the scientific research environment and facilities, strengthen the tailored guidance of mentors, and to fulfill the " holistic training (Three All-round Education)" in professional postgraduate training.

Optic disc drusen: a review / 中华眼底病杂志

Optic disc drusen (ODD) is an acellular deposit located in front of the cribriform of the optic disc. ODD has been much underdiagnosed due to few obvious clinical symptoms. These clinical symptoms are easily confused with optic disc edema caused by systemic high-risk diseases. The current mainstream view is that optic nerve fiber axon metabolism is disordered, leading to intracellular mitochondrial calcification. After axon chronic disintegration, calcified mitochondria continuously release outside the cell, resulting in a much higher concentration of extracellular calcium than inside the cell. The continuous deposit and accumulation of extracellular calcification fuse to small calcified corpuscles, which lead to ODD formation. OCT enhanced deep imaging can detect ODD sensitively, and its image feature is a weak reflection core completely or partially surrounded by a strong reflection edge. ODD is one of the common causes for optic disc crowding. During adolescence, the accumulating calcified bodies buried in the deep optic disc gradually extrude and migrate to the superficial optic disc, which turn into superficial ODD. As a consequence, part of these ODD patients rapidly progress during adolescence and generally become stable in adulthood with anterior ischemic optic neuropathy, or other vascular complications.

The blood lead level and its relationship with behavior in school-age children from rural areas of Chongqing / 中华预防医学杂志

Objective@#To explore the blood lead level and its relationship with behavior in school-age children from rural areas of Chongqing.@*Methods@#A total of 697 students from grades 3 to 6 in the fall semester of 2014 from 14 rural townships in one district of Chongqing was selected by using the random cluster sampling method. Blood were sampled to analyze the lead level. Neurobehavioral tests were performed to determine their personal cognitive and memory ability. Questionnaires and physical examinations were administered to obtain the information of confounding factors. All students were divided into Q1-Q4 groups according to the quartile of their blood lead level. The relationship between the blood lead level and behavior was analyzed by multivariate logistic regression model and restricted spline regression model.@*Results@#The mean age of 697 students was (10.07±1.36) years old, and the median (interquartile range) of their blood lead level was 44.31 (35.42) μg/L. Multivariate logistic regression model showed that after adjusting for age, gender, body mass index and maternal culture level, compared with Q1 group, the OR (95%CI) values of high digit symbol substitution test (DSST) scores and high overall memory quotient (MQ) scores in Q3 group were 1.65 (1.01-2.70) and 2.10 (1.21-3.62), and the OR (95%CI) value of high long term memory (LTM) scores in Q4 group was 0.53 (0.31-0.92). The results of the restricted spline regression model showed that the dose-response curves between the blood lead level and MQ/LTM test scores were both parabolic (P<0.05).@*Conclusion@#The blood lead level of school-age children from rural areas of Chongqing is the same as that from other areas of China, but slightly higher than that from other areas of Chongqing. Children with higher blood lead level have poor long-term memory ability.

Effect of cryptotanshinone on ferroptosis-related gene expression in lung cancer cells / 中国药理学通报

Aim To investigate the effects of cryptotanshinone on cell viability Aim To investigate the effects of cryptotanshinone on cell viability and ferroptosis-related gene expression in A549 and A549/DDP cells, and to explore its possible mechanisms. Methods A549 and A549/DDP cells were treated with different concentrations of CTS. Cell viability was measured by CCK-8 assay. The mRNA levels of TFR1, DMT1, IREB2, HSPB1, VDAC2, VDAC3 and GPX4 were measured by qPCR, and the protein levels of TFR1 were measured by Western blot. Results The cell viability was down-regulated by CTS in A549 and A549/DDP cells, while the cisplatin-resistant A549/DDP cells were more susceptible to CTS. After CTS treatment, the mRNA levels of ferroptosis-related genes showed different degrees of change. The mRNA levels of HSPB1 and GPX4 increased in A 5 4 9 cells , of which the mRNA levels of IREB2, VDAC2 and VDAC3 were reduced and the mRNA levels of TFR1 and DMT1 exhibited no significant change. The mRNA levels of TFR1 and IREB2 increased in A549/DDP cells, while the mRNA levels of VDAC3 decreased, and the expression levels of DMT1, HSPB1, VDAC2 and GPX4 did not changesignificantly. Conclusions Cryptotanshinone may inhibit the proliferation of lung cancer A549 and A549/DDP cells, and affect the expression of ferroptosis-re-lated genes.

The association between aflatoxin exposure and primary hepatocellular carcinoma risks: a case-control study in Chongqing / 中华预防医学杂志

Objective@#To investigate the association between aflatoxin exposure and primary hepatocellular carcinoma (PHC) development.@*Methods@#From December 2013 to May 2016, we selected 214 patients newly diagnosed with PHC as cases, and 214 patients as controls from three hospitals in Chongqing. Cases were confirmed with PHC diagnosis standard. And cases caused by clear reasons such as drug-induced liver injury, alcoholic liver damage, fatty liver and gallstones etiology, were excluded. Controls were included with no cancer and no digestive system disease, and recruited simultaneously with cases. Cases and controls were frequency-matched (1∶1) by same gender and age (±3 years). Peripheral blood and random urine samples were collected and analyzed for serum HBsAg status by biochemistry analyzer, and serum AFB1-ALB adduct and urinary AFB1-N7-GUA adduct by ELISA. Basic information, living habits and history of disease for patients were obtained by questionnaires. We used wilcoxon rank sum test to compare the median of serum AFB1-ALB adduct and urinary AFB1-N7-GUA adduct in cases and controls. Logistic regression analyses were performed to assess risk factors for PHC, and synergism index (S) of aflatoxin with other factors was estimated by the method of Andersson.@*Results@#There was no significant difference in age between PHC cases (50.74±9.67) years and controls (51.15±9.90) years. Logistic regression showed that the odds ratio of HBV infection for PHC development was 46.3 (95% CI: 23.3-88.0). There was a significant difference in median concentrations of serum AFB1-ALB adduct (cases vs controls: 146.23 vs 74.42 ng/g albumin, P<0.001), but no difference in median concentrations of urinary AFB1-N7-GUA adduct was observed (cases vs controls: 0.17 vs 0.14 ng/mg creatinine, P<0.210). The odd ratios for PHC risk after adjustment were 1.9 (95%CI: 1.1-3.4) for AFB1-ALB adduct, and 2.1 (95%CI: 1.0-4.2) for AFB1-N7-GUA adduct. Moreover, we observed a positive interaction of aflatoxin exposure with HBV, alcohol drinking, and diabetes. The S was 4.7 (95%CI: 2.8-7.9), 3.5 (95%CI: 1.0-12.0), and 12.4 (95%CI: 1.8-84.2), respectively for serum AFB1-ALB adduct with each of the three factors mentioned, and was 1.9 (95%CI:1.1-3.1), 2.0 (95%CI: 1.1-3.6), and 2.0 (95%CI: 1.1-3.6), respectively for urinary AFB1-N7-GUA adduct with each of the three factors mentioned.@*Conclusion@#HBV was still the main risk factor, and AFB1 exposure was also an independent risk factor for PHC in Chongqing. There was a positive interaction of aflatoxin with HBV, alcohol drinking, and diabetes.

The application of syphilis detection in the pre-pregnancy eugenics inspection / 国际检验医学杂志

Objective To investigate the application of syphilis detection in the pre-pregnancy eugenics inspection.Methods 12 900 women who attended the national free pre-pregnancy eugenics inspection from March 201 1 to October 2013 were selected as subjects.The treponema pallidum particle agglutination assay(TPPA)and rapid plasma regain test(RPR)were conducted among them before pregnancy,and the results of syphilis detections were recorded and compared.Results In 12 900 women,63 cases (0.49%)were syphilis positive in RPR tests,129 cases(1.00%)were syphilis positive in TPPA test,and 45 cases(0.35%)were syphilis positive both in RPR and TPPA tests.There were significant differences in positive rates of syphilis between that in the RPR test and that in the TPPA test(P <0.05),while no significant differences were found in positive rates of syphilis between that in the RPR test and that in the combined detection of RPR test and TPPA test.There were significant differences in positive rate of syphilis between that in the TPPA test and that in the combined detection of RPR test and TPPA test(P <0.05).The sensitivity of RPR test and TPPA test was 71.4% and 34.9%,respectively.Conclusion Both the RPR test and TPPA test could be the fast and ef-fective method in diagnosis of syphilis.However,RPR test might be more sensitive,which could be widely used in the pre-pregnancy eugen-ics healthy screening.Moreover,the diagnosis results could be confirmed by combination of RPR test and TPPA test.

Preparation and immunogenicity of a Pichia pastoris-derived hepatitis B vaccine containing preS1, preS2 and S epitopes / 生物工程学报

The preparation process and immunogenicity of a novel hepatitis B vaccine containing preS1, preS2 and S epitopes were investigated in this study. A Pichia pastoris stain GS115-SS1S2 harbouring two chimeric HBsAg gene constructs, SS1 and SS2 was cultivated by high-density fermentation. 300-600 mg/L of the expression level was achieved through 48-72 h methanol induction. SSIS2 antigen was extracted and purified by silica adsorption, HIC and SEC to 99% purity from the harvested cells. 82 mg purified antigen could be achieved from one liter of fermentation culture. The immunogenicity of the purified antigen was evaluated in NIH mice. Three groups of female NIH mice, 14-16 g in weight, were injected once intraperitoneally with 2.5, 0.625, 0.156 microg of each of the two vaccines: SS1S2 or a commercially available S vaccine. Part of the mice were bled in 30 days after injection to compare the ED50 of the two vaccines. For the SSIS2 vaccine, the ED50 is 0.46, 0.29 and 0.84 microg respectively for the preS1, preS2 and S antigens. For the S vaccine, the ED50 is 0.99 microg for the S antigen. Another part of the mice were bleed in 7 or 14 days to detect preS1, preS2 and S antibodies. Higher ratios of mice were seroconverted for preS1 and preS2 antibodies as compared to the S antibody in these two time points. These results suggest that the SS1S2 vaccine may be more immunogenic than the conventional S vaccines.

Study on the intervention effect of Qileng decoction (芪棱汤) on mitochondria mediated and caspase-9 dependent apoptopic pathway / 中国中西医结合急救杂志

Objective: To evaluate the effects and partly mechanism of Qileng decoction(QLD,芪棱汤) resisting focal cerebral ischemia/reperfusion(I/R) injury in rats by apoptosis and signal transduction pathway.Methods: The rats were randomly divided into three groups including sham operation group,normal saline(NS) control group and QLD group.The model of focal cerebral I/R injury was induced by using modified thread embolizing in rats.Rats were evaluated by neurologic function score at 2 hours after ischemia and 2,4,6,12,24 and 48 hours after cerebral reperfusion,and the pathological changes of nerve cells and mitochondria ultrastructure at pallium and hippocampus CA1 region were observed at 24 hours after reperfusion.Immunohistochemical method was performed to examine the expression of cytochrome C(cyt C) and caspase-9 at different time points after reperfusion.Apoptosis of nerve cells in ischemic penumbra(IP) was also characterized by terminal deoxynucleotidyl-transferase mediated dUTP-biotin nick end labeling(TUNEL) method.Results: Compared with NS control group,neurologic function scores at different reperfusion time points were improved and the pathological changes were ameliorated at 24 hours after cerebral I/R in QLD group.Mitochondria hydropsia was alleviated,mitochondrial cristae fragmentation and granulum basale shedding were diminished,and mitochondrial basical morphology was retained.Meanwhile,apoptosis index(AI) was decreased and the expressions of cyt C and caspase-9 were reduced in IP in QLD group.Conclusion: QLD intervenes in mitochondria mediated and caspase-9 dependent apoptopic pathway.QLD lowers AI and plays a role of protecting nerve by maintaining mitochondrial basical form,stabilizing mitochondrial membrane and inhibiting the release of cyt C and activation of caspase-9.The above actions are possibly some parts of mechanisms of QLD resisting focal cerebral I/R injury.

Simultaneous expression of modified hepatitis B surface antigen fusion polypeptides containing preS1, preS2 epitopes in Pichia pastoris / 生物工程学报

At present time, the widely used hepatitis B virus( HBV) vaccines consist of only the small hepatitis B surface antigen expressed in yeast or CHO cells. The frequency of non-responders to these vaccines has increased the demand for a more immunogenic vaccine. Some studies have suggested that the addition of preS region to the vaccine will improve its efficacy. However, the large protein (L) containing the whole preS region can not be effectively expressed in vitro. To overcome this problem, two chimeric contructs, SS1, surface gene containing preS1 region at C-terminus and SS2, surface gene containing preS2 region at C-terminus, were constructed and effectively expressed in our previous studies. Here we further constructed an expression vector containing both SS1 and SS2 expression cassettes by separation and ligation the SS2 cassette to a linearized SS1 expression vector pAO815-SS1. The recombinant vector was transformed into Pichia pastoris GS115 by electroporation. A high-level expression strain (GS115-SS1S2) was established by primary screening for His+ transformants and further analysis for induction products. ELISA results demonstrated that the expressed protein had S, preS1 and preS2 antigenicities simultaneously. Western blotting showed that the product can bind to all of the three antibodies, anti-S, anti-preS1 and anti-preS2. The expression protein was present in the form of particles of 20-35 nm diameter and the yield of recombinant particles reached 300-600 mg/L by fermentation. The SS1 and SS2 polypeptides kept intact in purified particles, suggesting that the stability of preS region has been significantly improved.