Objective To investigate the interest,cognition degree,participation degree and current situation of the advanced undergraduate clinical students in our college,to discuss the reason for low level of students' scientific research quality,in order to provide the reference to making research training programs for them.Methods The advanced undergraduates of seven-year and five-year clinical program interned in orthopedics department from January to June in 2014 were selected with cluster sampling method,and investigated anonymously by questionnaires and interview.120 students were investigated by questionnaire,and 120 effective questionnaires were taken back.30 students were interviewed.Results The results showed that 90.0 percent (n=108) of students were interested in scientific activity,and 47.5 percent (n=57) of students had participated in scientific lectures.In interviews,students think factors hindering the research on the participation in scientific research are:1)too many courses and heavy school tasks;2) absence of relative knowledge;3) lack of support from college;4) tough condition for scientific training;5) immature management system.Conclusion The advanced undergraduate clinical students had great interest in scientific activity,but had few opportunities to take part in,leading to their low level of scientific research quality.A variety of measures should be taken to bolster their scientific training.

Microbial nitrilases have attracted increasing attention in nitrile hydrolysis for carboxylic acid production in recent years. A bacterium with nitrilase activity was isolated and identified as Pseudomonas putida CGMCC3830 based on its morphology, physiological and biochemical characteristics, as well as 16S rRNA gene sequence. The nitrilase production was optimized by varying culture conditions using the one-factor-at-a-time method and response surface methodology. Glycerol 13.54 g/L, tryptone 11.59 g/L, yeast extract 5.21 g/L, KH2PO4 1 g/L, NaCl 1 g/L, urea 1 g/L, initial pH 6.0 and culture temperature 30 degrees C were proved to be the optimal culture conditions. It resulted in the maximal nitrilase production of 36.12 U/mL from 2.02 U/mL. Investigations on substrate specificity demonstrate P. putida nitrilase preferentially hydrolyze aromatic nitriles. When applied in nicotinic acid synthesis, 2 mg/mL P. putida cells completely hydrolyzed 20.8 g/L 3-cyanopyridine into nicotinic acid in 90 min. The results indicated P. putida CGMCC3830 displayed potential for industrial production of nicotinic acid.
Aminohydrolases ; biosynthesis ; Culture Media ; Hydrolysis ; Niacin ; biosynthesis ; Nitriles ; metabolism ; Pseudomonas putida ; enzymology ; Pyridines ; metabolism ; RNA, Ribosomal, 16S ; genetics ; Substrate Specificity ; Temperature

Objective To establish an online quantitative analysis model for moisture content assay of hydroxychloroquine sulfate particles by near infrared (NIR) spectroscopy. Methods The NIR spectra were collected in real time when the material particles were dried in the fluidized bed. Meanwhile the water content of the particles was measured with the standard moisture tester. The multiplicative signal correction (MSC) and first derivative followed by Karl Norris smoothing were used for spectra pretreatment. Two spectral range (4 935−5 336 cm⁻¹ and 6 911−7 297 cm⁻¹) were selected for the quantitative model with the partial least squares (PLS) regression. Results The quantitative calibration model had good correlation coefficients with Rc value=0.952 9 and Rp value=0.936 6. The root mean square error of calibration (RMSEC) was 0.408 and the root mean square error of prediction error (RMSEP) was 0.435. The ratio of standard deviation of validation set to prediction standard deviation (RPD) was 5.18. There was no significant difference between the predicted value and the reference value by t test when the established model was applied in large-scale production. Conclusion The online model established for monitoring water content has high accuracy and stability, which can be applied in industrial scale process to monitor the particle moisture in real time.

Objective To explore the mediating effect of facial emotion recognition on prosocial behavior of medical students in mask-obscured scenes.Methods Fifty-three medical students from a medical university in Chongqing were enrolled from July to September 2023 to complete the facial emotion recognition task,the dictator gaming task and the state empathy test.Spearman correlation analysis was used to examine the correlation between mask wearing and state empathy,trait empathy and prosocial behaviours,and the PROCESS procedure was used to test the mediation of state empathy and the moderating effect of mask wearing or not.Results ①mask wearing,state empathy and prosocial behaviour were significantly correlated(P＜0.01);② State empathy exerted mediated effect between facial emotion recognition and prosocial behavior,with the largest effect size(47％)for the relative mediating effect of sadness;③The interaction terms of facial emotion recognition and mask wearing had a significant effect on state empathy(P＜0.05).Conclusion Facial emotion recognition can influence prosocial behavior directly and also exert indirect effect on prosocial behavior through state empathy.Compared to the condition without mask wearing,mask wearing can significantly facilitate the effect of happy,sad and neutral emotions on state empathy.

Taiwanofungus camphoratus is a valuable and rare medicinal mushroom with various bioactivities, such as liver protection and anti-cancer. T. camphoratus can produce many arthroconidia at the end of submerged fermentation, but molecular mechanism underlying this submerged conidiation remains unknown. In this study, we found that Ca²⁺ concentration in culture medium significantly affected the arthroconidium production of T. camphoratus. Then, we identified two proteins (CaM and HSP90) involved in Ca²⁺/calmodulin signaling pathway and one protein (AbaA) involved in FluG-mediated conidiation pathway by two-dimensional electrophoresis analyses. Furthermore, we proposed a Ca²⁺/calmodulin- and FluG-mediated signaling pathway by bioinformatics analysis. By real-time quantitative PCR analyses of 23 key genes in the Ca²⁺/calmodulin- and FluG-mediated conidiation pathway, we found that expression levels of 7 genes (crz1, hsp90, flbB, brlA, abaA, wetA and fadA) showed significant responses to Ca²⁺ concentration in fermentation medium. Our research is beneficial for elucidating the underlying mechanism of submerged fermentation conidiation for T. camphoratus.

Anoctamin 1 (ANO1) is a kind of calcium-activated chloride channel involved in nerve depolarization. ANO1 inhibitors display significant analgesic activity by the local peripheral and intrathecal administration. In this study, several thiophenecarboxylic acid and benzoic acid derivatives were identified as novel ANO1 inhibitors through the shape-based virtual screening, among which the 4-arylthiophene-3-carboxylic acid analogues with the best ANO1 inhibitory activity were designed, synthesized and compound

Dopamine D₃ receptor (D₃R) is implicated in multiple psychotic symptoms. Increasing the D₃R selectivity over dopamine D₂ receptor (D₂R) would facilitate the antipsychotic treatments. Herein, novel carbazole and tetrahydro-carboline derivatives were reported as D₃R selective ligands. Through a structure-based virtual screen, ZLG-25 (D₃R K_i = 685 nmol/L; D₂R K_i > 10,000 nmol/L) was identified as a novel D₃R selective bitopic ligand with a carbazole scaffold. Scaffolds hopping led to the discovery of novel D₃R-selective analogs with tetrahydro-β-carboline or tetrahydro-γ-carboline core. Further functional studies showed that most derivatives acted as hD₃R-selective antagonists. Several lead compounds could dose-dependently inhibit the MK-801-induced hyperactivity. Additional investigation revealed that 23j and 36b could decrease the apomorphine-induced climbing without cataleptic reaction. Furthermore, 36b demonstrated unusual antidepressant-like activity in the forced swimming tests and the tail suspension tests, and alleviated the MK-801-induced disruption of novel object recognition in mice. Additionally, preliminary studies confirmed the favorable PK/PD profiles, no weight gain and limited serum prolactin levels in mice. These results revealed that 36b provided potential opportunities to new antipsychotic drugs with the multiple antipsychotic-like properties.

A new coronavirus (SARS-CoV-2) has been identified as the etiologic agent for the COVID-19 outbreak. Currently, effective treatment options remain very limited for this disease; therefore, there is an urgent need to identify new anti-COVID-19 agents. In this study, we screened over 6,000 compounds that included approved drugs, drug candidates in clinical trials, and pharmacologically active compounds to identify leads that target the SARS-CoV-2 papain-like protease (PLpro). Together with main protease (M
Antiviral Agents/therapeutic use* ; Binding Sites ; COVID-19/virology* ; Coronavirus Papain-Like Proteases/metabolism* ; Crystallography, X-Ray ; Drug Evaluation, Preclinical ; Drug Repositioning ; High-Throughput Screening Assays/methods* ; Humans ; Imidazoles/therapeutic use* ; Inhibitory Concentration 50 ; Molecular Dynamics Simulation ; Mutagenesis, Site-Directed ; Naphthoquinones/therapeutic use* ; Protease Inhibitors/therapeutic use* ; Protein Structure, Tertiary ; Recombinant Proteins/isolation & purification* ; SARS-CoV-2/isolation & purification*

The global COVID-19 coronavirus pandemic has infected over 109 million people, leading to over 2 million deaths up to date and still lacking of effective drugs for patient treatment. Here, we screened about 1.8 million small molecules against the main protease (M^pro) and papain like protease (PL^pro), two major proteases in severe acute respiratory syndrome-coronavirus 2 genome, and identified 1851M^pro inhibitors and 205 PL^pro inhibitors with low nmol/l activity of the best hits. Among these inhibitors, eight small molecules showed dual inhibition effects on both M^pro and PL^pro, exhibiting potential as better candidates for COVID-19 treatment. The best inhibitors of each protease were tested in antiviral assay, with over 40% of M^pro inhibitors and over 20% of PL^pro inhibitors showing high potency in viral inhibition with low cytotoxicity. The X-ray crystal structure of SARS-CoV-2 M^pro in complex with its potent inhibitor 4a was determined at 1.8 Å resolution. Together with docking assays, our results provide a comprehensive resource for future research on anti-SARS-CoV-2 drug development.
Humans ; Antiviral Agents/chemistry* ; COVID-19 ; COVID-19 Drug Treatment ; High-Throughput Screening Assays ; Molecular Docking Simulation ; Protease Inhibitors/chemistry* ; SARS-CoV-2/enzymology* ; Viral Nonstructural Proteins