Objective To clone the gene of autolysin(LytA) which are from different clinical strains of Streptococcus pneumoniae and express them in Escherichia coli. Methods The LytA gene was amplified by PCR from the total DNA of S.pneumoniae. Primers were designed according to the LytA gene sequence of R6. Recombinant plasmids were constructed and the sequences of different clinical strains were analyzed through method of bioinformatics. The cloned genes were expressed in E.coli and detected by SDS-PAGE. Results Complete LytA gene were amplified from all of the different clinical strains of S.pneumoniae and recombinant plasmids pGEX-4T-1-LytA were constructed successfully. After comparing the sequence of DNA and supposed protein, we find some differences. Induced by IPTG, LytA gene was expressed effectively in E.coli Jm109. Result of SDS-PAGE showed that the molecular weight of expressed protein was 62 kD, the same as calculated. Conclusions The sequences encoding LytA from different clinical strains of S.pneumoniae were cloned, the recombinant plasmids pGEX-4T-1-LytA was constructed successfully. Sequence analysis showed that there have difference among the gene and amino acid sequences of LytA from different clinical strains. Further studies should be focused on whether the difference contributes to activity of autolysin and the drug-resistance of S.pneumoniae.

β2-Microglobulin is a small molecule protein, consisting of a polypeptide chain.Previous studies have confirmed that serum β2-microglobulin is a biomarker that reflects early renal function injury, and renal function injury is closely correlated with ischemic stroke.Studies in recent years have shown that the level of serum β2-microglobulin increases significantly in patients with ischemic stroke.Thus, it can be used as a biomarker for the risk of ischemic stroke.

Massive open online courses (MOOCs) , which has caused a large scale of medical edu-cation in recent years, has led to an exploration boom in medical education. By the end of November 2014, on four large domestic and foreign MOOCs platform, a total of 178 medical related MOOCs were found, accounting for 12.2% of the total number of courses, among which public health MOOCs accounted for 44.9%. In terms of medical education, MOOCs are not only a powerful supplement of existing medical ed-ucation and can assist dissemination of medical knowledge, they can also promote pedagogy innovation and improve teaching quality to a certain extent. Moreover, the huge amounts of data collected by MOOCs can also be used to develop research of students' learning behavior. In addition, by recruiting study objects, the researchers have begun to use MOOCs supporting scientific research. As a novel educational development, MOOCs face many challenges while they bring opportuni-ties for medical education. However, active prac-tice and exploration will bring more powerful vitality for its development in the medical field.

Objective To evaluate the protective effectiveness of intranasal immunizations with recombinated-pneumococcal autolysin(Re-LytA), which protects mice against local and systemic Streptococ- cus pneumoniae(Sp) infection. Methods Testing group (group A): CpG as an adjuvant, the mice were intranasally immunized with purified Re-LytA, obtained by affinity chromatograph. The negative control group(group B) were intranasally immunized with sterile saline. And the positive control group (group C) were received 23-valent polysaccharide commercial vaccine through intramuscular injection. All the samples were collected 2 weeks post the last immunization. The levels of antibody was determined by ELISA. Then the mice were challenged intraperitoneally and intranasally with Sp, respectively. The infection and coloniza- tion was followed by monitoring colony-forming units of Sp in the blood, homogenized lung, and nasopharyn- geal lavage fluid 4 days post intranasal immunization. The mice were observed daily to note the livability of each group. Results The level of the LytA antibody (IgG, IgA, slgA) in group A were higher than that in group B and C (P < 0.05). Neither the LytA nor polysaccharide antibody could be detected in group B. Polysaccharide antibody could be detected in group C. After challenged intraperitoneally there was no signifi- cant difference in survival rates between group A and group C (P > 0.05), which was significant higher than that in group B (P <0.05). After challenged intranasally, compared with the group A, the geometric mean colony-forming units washed from the nasopharyngeal lavage fluid of the group B and group C were signifi- cantly higher (P <0.05). Conclusion lntranasal immunizations with Re-LytA can protect mice against lo- cal and systemic pneumococcal infection, and the protective immunity may be related to sIgA.

In recent years, the concept of " microbiome-gut-brain axis" has been proposed to reveal the wide connection between gut microbiome and nervous system diseases. As a common and frequently occurring disease of nervous system, the occurrence and outcome of ischemic stroke are closely related to gut microbiome. This article reviews the relationship between gut microbiome and risk factors of ischemic stroke and immune inflammation after stroke.

Objective:To explore the association and gene-environment interaction between single nu-cleotide polymorphisms (SNPs)involved in cell-cell adhesion and non-syndromic cleft lip with or without cleft palate (NSCL/P)among Chinese population.Methods:A total of 806 NSCL/P trios were drawn by an international consortium,which conducted a genome-wide association study (GWAS)using a case-parent trio design to investigate genes affecting risks to NSCL/P.The transmission disequilibrium test (TDT)was used to explore the association between cell-cell adhesion genes,including CDH1,CT-NNB1,PVRL1,PVRL2,PVRL3,ACTN1,VCL,LEF1,and NSCL/P.Conditional Logistic regression models were used to estimate effects on risk of exposed and unexposed children.Four common maternal exposures including maternal smoking,environmental tobacco smoke,alcohol consumption and multivita-min supplementation during pregnancy were included in this study.Results:A total of 226 SNP markers were tested after quality control in this study.Although 23 SNPs in three genes (CTNNB1,CDH1, ACTN1)showed nominal significant association with NSCL/P in the TDT (P <0.05).There were no sig-nificant evidence of linkage and association that remained in the transmission disequilibrium test after Bonferroni correction(P >0.000 2).Tests for gene-environment interaction yielded significant results be-tween rs7431 27 in ACTN1 and environmental tobacco smoke (P =0.000 1 )with an estimated OR (case |G and E)=2.00(95%CI:1 .23 -3.26)and OR (case |G no E)=0.59 (95%CI:0.38 -0.90).Among the lower P value results in gene-environment tests,there were no significant results be-tween rs1 475034,rs370535,rs227341 9 in ACTN1,rs1 06871 in CTNNB1 and environmental tobacco smoke interaction.There were also no significant results between rs7634000,rs2971 366,rs2634553, rs1 489032,rs762481 2 in PVRL3 and multivitamin supplementation during pregnancy in gene-environ-ment tests(P >0.000 2).Conclusion:There is no association between cell-cell adhesion genes,inclu-ding CDH1,CTNNB1,PVRL1,PVRL2,PVRL3,ACTN1,VCL,LEF1,and NSCL/P when the genes are considered alone.But our results suggest that SNPs in ACTN1 may influence the risk to NSCL/P through gene-environment interaction.

Objective To study the effect of high rosuvastatin dose on outcome in patients with large artery atherosclerotic stroke (LAAS).Methods Eighty-two LAAS patients were randomly divided into high rosuvastatin dose group (n=39) and routine rosuvastatin dose group (n=43).Their serum blood lipid level and inflammatory indexes were measured and their clinical outcome was assessed.Results No significant difference was found in mortality,recurrence and hemorrhagic transformation between the two groups (P＞0.05).The rate of improved outcome was significantly higher in high rosuvastatin dose group than in routine rosuvastatin dose group (84.62％ vs 65.12％,P=0.04).The serum hs-CRP level was significantly lower in routine rosuvastatin dose group and high rosuvastatin dose group after treatment than before treatment (0.56±0.60 mg/L vs 0.70±0.68 mg/L,P=0.01;0.22±0.29 mg/L vs 0.69±0.58mg/L,P=0.00) and in high rosuvastatin dose group than in routine rosuvastatin dose group after treatment than before treatment (0.22±0.29 mg/L vs 0.56±0.60 mg/L,P=0.00).The rate of LDL C＜1.8 mmol/L and non HDL-C＜2.6 mmol/L was significantly higher in high rosuvastatin dose group than in rosuvastatin dose group after treatment (69.23％ vs 46.51％,P=0.04;66.67％ vs 41.86％,P=0.03).No significant adverse reactions occurred in both groups.Conclusion High rosuvastatin dose can effectively increase the blood lipid level,reduce the serum hs-CRP level,and improve the clinical outcome in LAAS patients.

Recent studies have shown that there is a mutual influence between gut microbiota and stroke. Stroke-associated pneumonia (SAP) is a common complication of stroke, which is closely associated with death and poor prognosis of patients. Gut microbiota translocation may be the source of infection of SAP, but the specific mechanism of gut microbiota and SAP remains unclear. This article reviews the relationship between gut microbiota and SAP in order to provide reference for the prevention and treatment of SAP.