Pneumonia caused by SARS-CoV-2 has seriously threatened human life and health worldwide and caused a large number of deaths. Viral infection and acute inflammation are important causes of death, so it is particularly important to combine antiviral therapy with anti-inflammatory therapy. Glycyrrhizic acid, the main component of the glycyrrhizic root extract, has a wide range of pharmacological effects as well as high efficiency and low toxicity, its preparation has been widely used in the treatment of chronic hepatitis and other diseases. Glycyrrhizic acid can regulate the expression and release of a variety of cytokines and play a significant anti-inflammatory effect. At the same time, glycyrrhizic acid also showed significant inhibition towards a variety types of viruses. Therefore, the potential application of glycyrrhizic acid as COVID-19 treatment should be explored.

The fcl gene encodes GDP-fucose synthase, which catalyzes two-step differential isomerase and reductase reactions in the synthesis of GDP-L-fucose from GDP-D-mannose. It also participates in the biosynthesis of amino sugar and ribose sugar, and is one of the key enzymes to regulate the metabolism of sugar and nucleotides in organisms. The presence of fcl gene in Saccharopolyspora pogona was found through sequencing result of genome. The mutant S. pogona-fcl and S. pogona-Δfcl were constructed by gene engineering technology. The results showed that the gene had an effects on growth and development, protein expression and transcriptional level, insecticidal activity, and biosynthesis of butenyl-spinosyn of Saccharopolyspora pogona. The results of HPLC analysis showed that the yield of butenyl-spinosyn in S. pogona-Δfcl was 130% compared with that in S. pogona, which reduced by 25% in S. pogona-fcl. The results of determination of insecticidal activity showed that S. pogona-Δfcl had a stronger insecticidal activity against Helicoverpa armigera than that of S. pogona, while the S. pogona-fcl had a lower insecticidal activity against Helicoverpa armigera compared with S. pogona. Scanning electron microscopy (SEM) was used to observe the morphology of the mycelia. It was found that the surface of the S. pogona-Δfcl was wrinkled, and the mycelium showed a short rod shape. There was no significant difference in mycelial morphology between S. pogona-fcl and S. pogona. Aboved all showed that deletion of fcl gene in S. pogona hindered the growth and development of mycelia, but was beneficial to increase the biosynthesis of butenyl-spinosyn and improve insecticidal activity. Whereas the fcl gene over-expression was not conducive to the biosynthesis of butenyl-spinosyn and reduced their insecticidal activity. SDS-PAGE results showed that the difference of protein expression among the three strains was most obvious at 96 hours, which was identified by real-time fluorescence quantitative polymerase chain reaction, the results showed that there were significant differences of related genes in transcriptional levels among the three strains. Based on the results of the study, a network metabolic control map was constructed to analyze the effect of fcl gene on growth and the regulation pathway of butenyl-spinosyn biosynthesis, which provided an experimental basis for revealing the regulation mechanism of butenyl-spinosyn biosynthesis and related follow-up studies.
Bacterial Proteins ; Genetic Engineering ; Insecticides ; Macrolides ; Saccharopolyspora

Through introducing mutations into ribosomes by obtaining spontaneous drug resistance of microorganisms, ribosome engineering technology is an effective approach to develop mutant strains that overproduce secondary metabolites. In this study, ribosome engineering was used to improve the yield of butenyl-spinosyns produced by Saccharopolyspora pogona by screening streptomycin resistant mutants. The yields of butenyl-spinosyns were then analyzed and compared with the parent strain. Among the mutants, S13 displayed the greatest increase in the yield of butenyl-spinosyns, which was 1.79 fold higher than that in the parent strain. Further analysis of the metabolite profile of S13 by mass spectrometry lead to the discovery of Spinosyn α1, which was absent from the parent strain. DNA sequencing showed that there existed two point mutations in the conserved regions of rpsL gene which encodes ribosomal protein S12 in S13. The mutations occurred a C to A and a C to T transversion mutations occurred at nucleotide pair 314 and 320 respectively, which resulted in the mutations of Proline (105) to Gultamine and Alanine (107) to Valine. It also demonstrated that S13 exhibited genetic stability even after five passages.
Genetic Engineering ; Macrolides ; metabolism ; Point Mutation ; Ribosomal Proteins ; genetics ; Ribosomes ; metabolism ; Saccharopolyspora ; metabolism

OBJECTIVETo study the oxidative damage and apoptosis of renal tubular epithelial cells (NRK-52e cell line) induced by ethylbenzene.

METHODSNRK-52e cells were exposed to 30, 60, 90, 120 μmol/L ethylbenzene for 24 hours. Cell viability were measured using MTT, the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT), the contents of malondialdehyde (MDA) and glutathione (GSH) were detected respectively. PI fluorescent staining assay was applied to detect percentage of apoptosis in ethylbenzene-treated groups.

RESULTSCompared with control group, cell outline became clear, cell diopter increased, cell became smaller and shrinkage, some cells broke in 60 μmol/L ethylbenzene-treated group. Plenty of cells died, suspension cells increased significantly in 90 μmol/L ethylbenzene-treated group. Compared with control group, cell viability the activities of SOD and CAT and the content of GSH were significantly decreased in 60 and 90 μmol/L ethylbenzene-treated groups (P<0.05). The MDA content were remarkably elevated in 90 μmol/L ethylbenzene-treated groups (P<0.05).

CONCLUSIONEthylbenzene can induce oxidative stress and apoptosis in NRK-52e cells (P<0.05).

Animals ; Apoptosis ; drug effects ; Benzene Derivatives ; toxicity ; Cell Line ; Epithelial Cells ; drug effects ; metabolism ; Kidney Tubules ; cytology ; Oxidation-Reduction ; Oxidative Stress ; drug effects ; Rats ; Reactive Oxygen Species ; metabolism

OBJECTIVETo investigate the effect of long-term exposure to toluene diisocyanate (TDI) on the lung function of TDI-exposed workers.

METHODSA factory was selected for this occupational epidemiological investigation. The workers who were exposed to TDI and had complete physical examination records in recent 3 years were the exposed group (n = 45), while the company's administrative staff, logistics staff, and other non-TDI-exposed workers who had complete physical examination records in recent 3 years were the control group (n = 47). The two groups were compared in terms of lung function indices.

RESULTSCompared with the control group, the 2009 exposure group had significantly lower forced expiratory volume in one second (FEV1.0), FEV1.0/forced vital capacity (FVC), and maximal expiratory flow at 25% of FVC (MEF25) (P < 0.05), the 2010 exposure group had significantly lower FEV1.0, FEV1.0/FVC,maximum voluntary ventilation (MVV), and maximal expiratory flow at 50% of FVC (MEF50) (P < 0.05), and the 2011 exposure group had significantly lower FEV1.0, FEV1.0/FVC, peak expiratory flow (PEF), MEF25, and MEF50 (P < 0.05).

CONCLUSIONLong-term exposure to TDI can lead to certain impairment of lung function in workers, which may be reflected by decreased lung function indices such as vital capacity, FVC, FEV1.0, FEV1.0/FVC, PEF, and MVV.

Case-Control Studies ; Forced Expiratory Volume ; Humans ; Lung ; drug effects ; physiopathology ; Male ; Occupational Exposure ; Toluene 2,4-Diisocyanate ; adverse effects ; Vital Capacity ; drug effects

Objective To study the characteristics of surface electromyography (sEMG) during swallowing in normal adults.Methods The sEMG during swallowing was carried out in 126 normal adults.There were 66 males and 60 females with their age ranged from 18 to 65 years.The recording electrodes were placed on the skin above the superior thyroid notch and the duration and amplitude of muscle activities during every deglutition were recorded.Swallowing styles were dry swallow,20 ml water swallow and 40 ml water swallow.Results The durations of sEMG at dry swallow,20 ml water swallow and 40 ml water swallow were (1.133 ± 0.209) s ((x) ± s),(1.097 ± 0.208) s,and (1.5 10 ± 0.432) s,while the amplitudes were (0.332±0.115)mV,(0.308 ±0.095)mV,and (0.399 ±0.139)mV in normal male group.The durations of sEMG at dry swallow,20 ml water swallow and 40 ml water swallow were (1.118 ± 0.170)s,(1.085 ± 0.209) s,and (1.765 ± 0.463) s,while the amplitudes were (0.292 ± 0.100) mV,(0.261 ± 0.113)mV,and (0.342 ± 0.129)mV in normal female group.The amplitudes of sEMG in male were higher than those in female (P ＜ 0.05) and the durations had no statistically significant difference between male and female (P ＞ 0.05) in all swallow styles except that the duration of 40 ml water swallow in female was longer than that in male (P ＜ 0.05).In all volunteers,the durations of sEMG at 40 ml water swallow were longer than those at dry swallow and 20 ml water swallow,and there was no statistically significant difference between dry swallow and 20 ml water swallow.The amplitude of sEMG at 40 ml water swallow was higher than that at dry swallow.The amplitude of sEMG in dry swallow was higher than that at 20 ml water swallow.There was no statistically significant difference in durations and amplitudes of sEMG among four different age groups of male.In the female groups,there was no statistically significant difference in durations and amplitudes of sEMG among four different age groups except that the duration at 40 ml water swallow was longer in younger group (＜ 30 years old) than in older groups.Conclusions Surface EMG of swallowing is a simple and noninvasive method for evaluating the swallowing function.The sEMG data of swallowing in normal adults obtained in this study may be used to provide reference for screening swallowing function in adults in the future.

Objeetive To investigate the reliability,validity and clinical value of Chinese version of the reflux symptom index(RSI).Methods xThe Chinese version of RSI scale was used in ENT outpatient department.There were one hundred and seven patients,including thirty-five patients with common throat diseases (non-suspected) and seventy-two patients with clinically suspected throat reflux.All 107 patients were asked to complete the two scales one on the first-visiting and one after one week.Thirteen patients with common throat diseases (non-suspected) and forty-one with suspected throat reflux also received RSI testing.Among the thirty-four confirmed acid reflux disease patients,thirty patients received pharmaceutical treatments and self-performed post-RSI testing after three months.Results The RSI Scale internal reliability consistency included the test-retest reliability (0.715-0.971),discriminant validity and construct validity.RSI total targeting percentage was 66.7％,targeting percentage was 80.8％.Discriminant validity was confirmed using 2 independent samples Wilcoxon test,with RSI total score compared to Z =-3.266,P =0.001.The before and after treatment self-control chi-square test (P ＜ 0.05),the difference was statistically significant.Conclusion RSI Simplified Chinese version has good rcliability and validity,and can be used for laryngopharyngeal reflux disease (LPRD) diagnostic screening along with the efficacy for the treatment of patients with appropriate LPRD aids.

Objective The purpose of the present study was to identify the relationship between the plasma level of adiponectin and in-stent restenosis of patients with coronary heart disease after coronary stenting. Method The study population comprised 119 individuals (92 men ) who underwent stent implantation, including 65 subjects without in-stent restenosis (group A ) and 54 patients with in-stent restenosis (group B). The level of plasma adiponectin was measured using ELISA. Coronary angiography was performed immediately before and after implanting stent and 9-12 months later. Results Baseline characteristics including drug use after PCI were similar between the groups. The rate of implanting bare metal stent is 8(12. 31% ) and 6(11.11% ), TAXUS drug-eluting stent is 11 (16. 92% ) and 10(18.52%) and CYPHER drug-eluting stent is 46 ( 70. 77% ) and 38 ( 70. 37% ) respectively ( all P > 0. 05 ). Plasma level of adiponectin in patient of group A was significantly higher than that in group B [ ( 15. 16±5.02 )mg/L vs. ( 10. 01±4. 93 ) mg/L, P < 0. 05 ]. The quantitative coronary angiography ( QCA ) showed that lesion length was similar between groups [ ( 15.82±: 6. 67 ) mm vs. ( 13.40±4. 20 )mm, P > 0. 05 ], minimum lumen diameter(MLD) and stenosis rate were also similar before and after implanting stent ( P > 0. 05 ) and acute gain was ( 1.48±0. 65 ) mm vs. ( 1.19±0. 37 ) mm ( P > 0. 05 ). MLD was higher in group A than that in group B [(2.55±0.53)mm vs. (0.57±0.60)mm, P<0.01] at 9-12 months follow up. Restenosis rate [(24.2±11.2)% vs. (81.0±19.1)%,P<0.01] and late lumen loss [(0.50±0.34)mm vs.( 1.60± 0. 54)mm, P < 0. 01 ] were lower in group A than in group B. Conclusions The lower plasma adiponectin level might be associated with in-stent restenosis after coronary stenting.

Objective To modify the methods of operation and establishment of cerebral ischemia rat models made by thread occlusion. Method We randomly divided 120 male SD rats into a common group (n = 50), an improvement group (n = 60) and a sham-operated group (n - 10). Rats in the common and improvement groups were made into models using the common and improvement methods separately. All models were evaluated on the basis of physical sign indices and 2,3,5-triphenyltetrazolium chloride (TTC) staining. The TTC staining results were taken as gold standards. Then, we compared the achievement ratios of the two groups, and computed the sensitivity and specificity of every physical sign index based on these standards. The χ~2 or correction χ~2 test was used to compare the ratios. Results (1) The achievement ratio in the improvement group was significantly higher than that in the common group (71.67% vs. 52.00%, P = 0.034). (2) The sensitivity of evaluation for both common and improvement methods was 98.55%. However, the specificity of evaluation for the improvement method was significantly higher than that for the common method (100.00% vs. 40.00%, P =0.000). Conclusions The establishment achievement ratio and evaluation correctness of models are obviously elevated by modification of the operation and establishment methods.

OBJECTIVETo explore the association between monoamine oxidase A (MAOA) variable number tandem repeat (VNTR) polymorphism and major depression in Chinese Han population.

METHODSPolymerase chain reaction was used to genotype MAOA VNTR polymorphism. A total of 512 major depression patients and 566 normal controls were recruited in our study. These patients were also assessed using the 14-item Hamilton anxiety scale. RESULTS The allele frequency of MAOA VNTR was not significantly different between the male/female major depression patients and the normal controls. Compared with the normal controls, MAOA VNTR genotype was significantly more frequent in female major depression patients (P=0.002), but not in male patients (P=0.17). MAOA VNTR-L carrier was also associated with "fear" symptom in female patients (P=0.0056).

CONCLUSIONMAOA gene is associated with the major depression in Chinese Han population, especially among female patients.

Adolescent ; Adult ; Asian Continental Ancestry Group ; genetics ; Case-Control Studies ; China ; Depressive Disorder, Major ; genetics ; Female ; Genetic Predisposition to Disease ; Humans ; Male ; Minisatellite Repeats ; genetics ; Monoamine Oxidase ; genetics ; Polymorphism, Genetic ; Promoter Regions, Genetic ; genetics ; Young Adult