Bioinformatics analysis on structure and function and expression vector construction of SARS-CoV-2 related protein TMPRSS2 / 中国药理学通报

Aim Human TMPRSS2 is a transmembrane serine protease.In this paper, the structure and func¬tion of the protein were systematically analyzed by bioinformatics, the codon was optimized and the pro- karvotie expression vector was constructed to explore the molecular mechanism of SARS-CoV-2 infecting host cells.Methods The recombinant expression vector pET-22b-TMPRSS2 was generated by molecular clo¬ning technology.The homology, functional sites, sub¬cellular localization, three-dimensional structure and evolutionary characteristics of TMPRSS2 protein were systematically analyzed by using analytical tools such as Protparam, NetPhos3.1, Blast, Clustal X2 and MEGA7.0.Results The prokarvotic expression plas- mid was constructed correctly; TMPRSS2 belongs to medium molecular weight protein, which is composed of 492 amino acid residues.The theoretical isoelectric point is 8.12, the molecular extinction coefficient is 118 145 L • mol~1 • cm"1 , and the half-life is 30 h; TMPRSS2 has 15 potential glycosylation sites and 49 possible phosphorylation sites.It is a transmembrane hydrophilie protein without signal sequenee.In addi¬tion, the protein has 13 potential B-cell epitopes and 7 T-eell epitopes.Seeondarv structure analysis showed that random coil accounted for the highest proportion of TMPRSS2 protein ( 0.453 3) , followed by extended strand (0.252 0).Sequence comparison and evolu¬tionary analysis showed that the highest sequence con¬sistency and closest genetic relationship with human TMPRSS2 was Pan troglodytes, followed by gorilla.Conclusions Human-derived TMPRSS2 protein is ev- olutionarilv conserved and functionally important.Hie results of this study can help to reveal the structure and mechanism of action of TMPRSS2 protein, provide ide¬as for the diagnosis and treatment of COYID-19, and accelerate the research and development process of new drugs targeting TMPRSS2 protein.

Application of High Resolution Melting Curve Analysis in Detection of SLC4A1 Gene Mutation in Patients with Hereditary Spherocytosis / 中国实验血液学杂志

OBJECTIVE@#To investigate the feasibility and clinical significance of high resolution melting(HRM) curve analysis to detect SLC4A1 gene D38A and K56E mutations in the patients with hereditary spherocytosis(HS).@*METHODS@#Peripheral blood was collected from 23 cases of HS for routine tests and their genomic DNA was extracted by routine technique. Specific primers of mutation sites D38A and K56E of SLC4A1 gene were designed. The HRM method was used to analyze all the samples, and then the results of HRM were verified with DNA sequencing technology.@*RESULTS@#Among 23 specimens of HS patients, 6 cases of heterozygous mutant gene were detected by HRM technology, including 3 cases of D38A mutation and 3 cases of K56E mutation, which were confirmed by DNA sequencing.@*CONCLUSION@#The HRM technology can correctly detect 2 common mutation sites including D38A and K56E in SLC4A1 gene in an efficient, fast, and reliable way, which not only can be used for clinical diagnosis, but also expected to be a new method for clinical researchers to define gene mutation spectrum in HS patients.

High-frequency repetitive transcranial magnetic stimulation combined with neuromuscular electrical stimulation for the treatment of poststroke dysphagia: a randomized controlled trial / 国际脑血管病杂志

Objective To assess the therapeutic effect of high-frequency repetitive transcranial magnetic stimulation (rTMS) combined with neuromuscular electrical stimulation (NMES) on poststroke dysphagia.Methods A total of 90 patients with poststroke dysphagia were enrolled.They were randomly divided into either a NMES + rTMS group or a NMES + sham rTMS group (n =45 in each group).The Kuhota water drinking test and Standardized Swallowing Assessment (SSA) were used to assess the swallowing function.Results The scores of Kuhota water drinking test (F=82.001,P＜0.001) and the SSA (F =33.743,P ＜0.001) before treatment,treatment of one course,treatment of two courses,and at 3 months after treatment in the NMES + rTMS group had significant differences.Compared with before treatment,they were improved significantly for treatment of one course (P ＜0.01 and P ＜0.05,respectively),two courses (all P＜0.01),and at 3 months (all P＜0.01) after treatment.The scores of Kuhota water drinking test (F =53.647,P＜0.001) and the SSA (F=19.178,P＜0.001) in the NMES + sham rTMS group also had significant difference.Compared with before treatment,they had significant improvement for treatment of one course (all P ＜0.05),two courses (P ＜0.05 and P ＜0.01,respectively) and at 3 months (all P＜0.01)after treatment.The scores of Kuhota water drinking test for treatment of one course,two courses,and at 3 months after treatment (treatment of one course:t=2.217,P=0.02;treatment of two courses:t =2.406,P =0.019;at 3 months after treatment:t =2.128,P =0.037) and the SSA (treatment of one course:t =2.196,P =0.030,treatment of two courses:t =2.425,P =0.016;at 3 months after treatment:t =2.512,P=0.013) in the NMES + rTMS group were significantly better than those in the NMES + sham rTMS group.Conclusions High-frequency rTMS combined with NMES may significantly improve the swallowing function in patients with stroke.Its efficacy is superior to NMES.