Group A β-hemolytic streptococcus (GAS),namely Streptococcus pyogenes,is one of the most im-portant human pathogen.GAS can cause skin and mucous membrane superficial infectious diseases,life -threatening invasive disease,toxin -mediated diseases and immune -related diseases.Antibiotic is an effective mean to control GAS infection.The β-lactam antibiotics remain the first -choice treatment for GAS infection and the macrolides are often recommended as a replacement therapy for β-lactam antibiotics allergic patients or a means to blocking GAS exotoxin product.But with the widespread use of macrolides autibiotics,macrolide -resistant GAS spread in the world. This paper will elaborate the situation of macrolide -resistant clones.

Objective To investigate the relationships among cerebellar mutism (CM), relapsed medulloblastoma (MB) and the primary tumor location.MethodsA retrospective analysis was conducted in 114 children over 3 years old with MB from November 2011 to April 2015.ResultsThe median onset age was 84.7 months (36.4 to 184.7 months) in 114 children with MB (77 boys and 37 girls), of whom there were 48 cases of recurrence. There were twenty two cases of CM and the overall incidence of CM was 19.3% (22/114). The incidence of CM was 19.7% (13/66) in non-recurrent cases and 18.8% (9/48) in recur-rent cases, and there was no signiifcant difference between two groups (P=0.899). The incidence of CM was 17.6% (9/51) in cas-es with primary tumor in the fourth ventricle, 7.1% (1/14) in cases with primary tumor in the cerebellar vermis, 21.4% (3/14) in cases with primary tumor in both fourth ventricle and cerebellar vermis, 45.5% (5/11) in cases with primary tumor in fourth ven-tricle and other parts of the brain, and 50.0% (4/8) in cases with primary tumor in cerebellar vermis and other parts of the brain. No CM incidence was observed in cases with primary tumor in central nerve system except for the fourth ventricle and cerebellar vermis. The incidence of CM between the cases with fourth ventricle/cerebellar vermis involvement and those without fourth ventricle/ cerebellar vermis involvement had signiifcant difference (P=0.039). ConclusionsThere is no relationship between CM and relapsed MB. Children with MB whose primary tumor is located in the fourth ventricle and/or the cerebellar vermis is susceptible to CM.

Objective To investigate the effect of bone marrow mesenchymal stem cells (BMSCs) transplantation on angiogenesis and functional recovery after focal cerebral ischemia in rats.Methods BMSCs were isolated and cultured using the whole bone marrow adherent method,and conducted phenotypic identification using flow cytometry analysis of surface positive antigen of CD29,CD90 and the negative antigen of CD34,CD45.Rats were subjected to middle cerebral artery occlusion (MCAO) for 90 minutes,and divided into three groups randomly,the sham group,model group and BMSCs group.24 hours after cerebral ischemia,rats were injected with 1 ml BMSCs solution (1 × 106 cells/ml) or PBS via the tail vein.The modified neurological severity score(mNSS) test,the corner test and the adhesive tape test were used to evaluate sensorimotor function on the 1,7,14 and 28 days after ischemia.Infarcted volume was detected by toluidine blue staining,and the numbers of vWF positive microvessels and vascular endothelial growth factor (VEGF) positive cells in the ischemic boundary were determined by immunofluorescence.Results By flow cytometric analysis,the cell phenotype of passage 3 BMSCs showed that CD29,CD90,CD34 and CD45 were 98.3％,97.4％,0.2％ and 4.8％,respectively.Compared with the model group,BMSCs significantly reduced the score of mNSS(P＜0.01),the number of right turn of corner test(P＜0.05),latency of removal adhesive tape(P＜0.05) and the infarcted volume (P＜0.01).The numbers of vWF positive vesscls and the VEGF positive cells were (42.97±8.64)/mm2 and (54.83± 10.66)/mm2 at the boundary zone in model group 14 days after ischemia,respectively.BMSCs significantly increased the numbers of vWF positive vessels ((69.43± 7.29)/mm2) and VEGF positive cells ((78.70±6.16)/mm2,P＜0.01).Conclusion BMSCs can improve the functions of cerebral lesions after cerebral ischemia,which may be associated with the enhanced angiogenesis and VEGF expression in the ischemic boundary.

Objective To analyze the molecular biological characteristics of Streptococcus pyogenes (GAS) causing children tonsillitis in Yangfangdian community Haidian district,Beijing between 2011 and 2013.Methods From Apr.2011 to Apr.2013,there were 94 children with tonsillitis treated in outpatient of Beijing Shijitan Hospital Affiliated to Capital Medical University,and 17 strains GAS were isolated from these pediatrician outpatients.Their encoding mature M protein gene (emm gene),7 pairs of alleles housekeeping gene (gki,gtr,murI,mutS,recP,xpt and yqiL),superantigen speA and speC genes,macrolide-resistance genes ermB,mefA and ermRT were amplified by polymerase chain reaction (PCR).The PCR amplified products of emm gene and 7 pairs of alleles housekeeping gene were sequenced.The emm gene sequences were stored in the Centers for Disease Control and Prevention database.The emm types of GAS were identified.The 7 pairs of alleles housekeeping gene sequences of GAS were sent to the multilocus sequence typing (MLST) website for their iso-allelic sequences to identify their sequence types (ST).The PCR amplified products of superantigen gene speA and speC,macrolide-resistance genes ermB,mefA and ermRT were performed with agar gel electrophoresis.The corresponding qualitative results were obtained.Results Five emm-types were discovered:emm12.0 (76.4％),emm1.0 (5.9％),emm89.0 (5.9％),emm75.0 (5.9％) and emm22.0 (5.9％) ;emm12.0 and its subtype strains had the same allelic profiles which belonged to ST36 type; emm1.0 strain belonged to ST28 ; emm89.0 strain belonged to ST101 ; emm75.0 strain belonged to ST49 ; emm22.0 strain belonged to ST46 ; 94.1％ (16/17) strains carried macrolide-resistance gene ermB.None carried macrolide-resistance genes mefA and ermRT.None carried superantigen speA gene.100.0％ (17/17 cases) carried superantigen speC gene.Conclusions emm12.0 (ST36) strain was the most common type of GAS causing the children tonsillitis in Yangfangdian community Haidian District,Beijing between 2011 and 2013.These strains mainly carry macrolide-resistance ermB and superantigen speC gene.

Objective To investigate and summarize the MRI characteristics of splenic sclerosing angiomatoid nodular transformation (SANT).Methods A retrospective analysis of 5 SANT cases were analyzed,in terms of their MRI characteristics and pathological findings.Results MRI findings of SANT included:T1WI presents iso-signal or slightly low signal,all displayed lesions were detected as low signal compared with spleen,but higher than muscle signal on T2 WI,and with speck dots or starlike low signal in the central area,without necrosis and cystic change.The signal was significantly differentiated compared with the spleen on DWI.On chemical shift imaging,2 cases were showed slightly higher signal on out phase,the others without signal change.On enhanced scan,4 cases had edge obvious enhancement on arterial phase,inward filling enhancement,and the signal was higher than the spleen,1 case without arterial phase enhancement,but with mild concentric delayed enhancement.All of the speck dots and starlike areas decreased with time delay,with certain degree enhancement on delayed phase.Conclusions There were some MRI features of SANT,preoperative MRI can prompt diagnosis,but final diagnosis depends on pathology.

Objective To investigate the clinical characteristics of children with medulloblastoma (MB). Methods The correlations amongst MB histopathological subtype,age at diagnosis,gender,primary tumor locations, relapsed tumor and relapsed tumor locations were analyzed retrospectively in 83 children who were diagnosed as MB by histopathology subtypes from February 2012 to April 2015 in Beijing Shijitan Hospital Affiliated to Capital Medical Uni-versity.The data was conducted by using SPSS 22.0 statistical software.Results Among the 83 cases (53 boys and 30 girls),there were 14 patients younger than 3 years old (9 boys and 5 girls)and 69 patients (44 boys and 25 girls)ol-der than 3 years old,including 28 relapsed (19 boys and 9 girls)and 55 non -relapsed cases (34 boys and 21 girls). The median age was 80.2 (13.1 -184.7)months at diagnosis.Of these 83 cases,48.2% (40 /83 cases)was classic medulloblastoma (CMB)(2 cases less than 3 years old),24.1 % (20 /83 cases)was desmoplastic /nodular medullo-blastoma (DMB)(6 cases less than 3 years old),12.1 % (10 /83 cases)was large cell/anaplastic medulloblastoma (LC /AMB)(1 case less than 3 years old),3.6% (3 /83 cases)was extensive nodular medulloblastoma (MBEN)(1 case less than 3 years old),and 12.1 % (10 /83 cases)(3 cases less than 3 years old)was mixed subtype.The rela-tionships between age at diagnosis and histopathological subtype,gender and primary tumor location were all statistically significant (χ2 =0.014,0.013,all P <0.05).Conclusions The incidence of boys with MB is higher than girls.CMB is the main histopathologic subtype in children over 3 years old.The primary tumor location involving the cerebellar vermis or cerebellar vermis and the fourth ventricle is higher in girls with MB.The primary tumor location involving the fourth ventricle,the fourth ventricle and other parts of the central nervous system,Cerebellar vermis and other parts of the central nervous system or other parts of the central nervous system is higher in boys with MB.

Bisecting N-acetylglucosamine(GlcNAc),a GlcNAc linked to the core β-mannose resi-due via a β1,4 linkage,is a special type of N-glycosylation that has been reported to be involved in various biological processes,such as cell adhesion and fetal development.This N-glycan structure is abundant in human trophoblasts,which is postulated to be resistant to natural killer cell-mediated cytotoxicity,enabling a mother to nourish a fetus without rejection.In this study,we hypothesized that the human amniotic membrane,which serves as the last barrier for the fetus,may also express bisected-type glycans.To test this hypothesis,glycomic analysis of the human amniotic membrane was performed,and bisected N-glycans were detected.Furthermore,our pro-teomic data,which have been previously employed to explore human missing proteins,were ana-lyzed and the presence of bisecting GlcNAc-modified peptides was confirmed.A total of 41 glycoproteins with 43 glycopeptides were found to possess a bisecting GlcNAc,and 25 of these gly-coproteins were reported to exhibit this type of modification for the first time.These results provide insights into the potential roles of bisecting GlcNAc modification in the human amniotic membrane,and can be beneficial to functional studies on glycoproteins with bisecting GlcNAc modifications and functional studies on immune suppression in human placenta.

Objective: To learn the epidemiological characteristics of fall mortality among the elderly people in Taizhou，and to provide basis for intervention strategies of fall in the elderly. Methods: Data of fall mortality among residents aged 60 years or over in Taizhou from 2016 to 2018，collected from Zhejiang Chronic Disease Surveillance Information Management System，was used for analysis of time，population and geographical characteristics of fall deaths. The epidemic trend of fall mortality in the elderly was described by annual percentage change（APC）. Results: From 2016 to 2018，3 699 cases of fall death in Taizhou were reported，the crude and standardized mortality were 116.90/100 000 and 97.88/100 000. The standardized mortality of fall in women was 106.11/100 000，which was higher than 90.13/100 000 in men（P<0.05）. The standardized mortality of fall in rural residents was 131.20/100 000，which was higher than 28.15/100 000 in urban residents（P<0.05）. The mortality of fall in residents aged 65-69 years from 2016 to 2018 showed an upward trend（APC=4.20%，P<0.05），while the mortality trend of fall in other age groups was not statistically significant（P>0.05）. Conclusion Fall was the first cause of injury death in the elderly aged 60 years or over in Taizhou. Females and rural residents have relatively higher fall mortality.

Objective:To understand the current situation and influencing factors of depression among residents in Chongqing, and to explore the relationship between depression and administration satisfaction of the standardized residency training.Methods:Stratified random cluster sampling was used to select 372 residents currently participating the standardized residency training in Chongqing. The patient health questionnaire (PHQ-9) and administration satisfaction of residency training questionnaire were used to conduct a cross-sectional survey on the depression status and satisfaction of residents in Chongqing. SPSS 21.0 software package was used for partial correlation analysis and binary logistic regression analysis to explore the relationship between depression and administration satisfaction of the standardized residency training.Results:Among the 372 residents, 218 had mild depression and above (58.60%). There was a significant difference in the incidence of depression among residents of different ages, educational background, marital status, working hours and administration satisfaction of residency training ( χ2 = 23.02, 17.35, 12.24, 21.70, 95.20; P = 0.028, 0.027, 0.016, 0.041, <0.001 respectively). Partial correlation analysis showed that there was a negative correlation between the total score of depression and the five aspects of the administration satisfaction (total score, instructors, training base, managers and training income) ( r=-0.52, -0.45, -0.47, -0.45, -0.40, all P<0.01). In the binary logistic regression analysis of depression and satisfaction,the satisfaction had a negative impact on depression, and its B value was -1.71, and OR value was 0.18, P<0.001. Conclusion:The incidence of depression among residents in Chongqing is high. Age, educational background, marital status, working hours and administration satisfaction are related to the degree of depression. And the higher the degree of depression, the lower the administration satisfaction of residents. Relevant departments should pay attention to the mental health of residents and improve the quality of standardized residency training.

Objective To investigate the treatment value of intensified chemotherapy combined with intrathe-cal Methotrexate(ITMTX)in the treatment of children with relapsed medulloblastoma.Methods From February 2011 to February 2014,40 relapsed patients in Beijing Shijitan Hospital,Capital Medical University,aged 10.6 years(2.7 to 17.7 years),were received 4 cycles of carboplatin and Etoposide continuously infusion for 96 h,and sequentially fo-llowed with Ifosfamide,Etoposide and Nedaplatin for 3 cycles,then administrated oral Temozolomide(TMZ)and Etopo-side for 12 cycles.All patients were divided into ITMTX group,which were performed ITMTX during every chemothera-py or every 3 weeks,and no intrathecal Methotrexate(no-ITMTX)group,which were not performed with ITMTX.Re-sponses were evaluated,and the objective response time,time to tumor progress(TTP),time to treatment failure (TTF),and recurrence-free interval(RFI)of the two groups were contrasted.The side-effects of chemotherapy and ITMTX were analyzed,overall survival was calculated using Kaplan-Meier method,and chi-square test or t test was used to compare the difference between two groups.Results Until 30thDecember 2016,the follow-up time was 29.4 months(ranging from 2 to 57 months). The 3-year overall survival(OS)rate was(53.5 ± 8.1)%,and 45.0% pa-tients were objective response,and the mean objective response time was 2 months,and the RFI was 18 months.For IT-MTX patients,the 3-year OS rate was(66.6 ± 11.5)%,the objective response ratio was 70.0%,and mean objective response time was 1.5 months,24 months free-event of TTP and TTF was 70.0% and 90.0%,respectively,and the RFI was 22.5 months.For no-ITMTX patients,the 3-year OS rate was(40.0 ± 11.0)%,objective response ratio was 20.0%,and mean objective response time was 2.5 months(1.5-4.0 months),24 months free-event of TTP and TTF was 35.0% and 50.0%,respectively,and the RFI was 5 months(0-40 months).Compared with those of no-ITMTX patients,the RFI,24 months TTP and TTF of ITMTX patients were much better,there were statistical signi-ficances(all P<0.05).The main side-effects of chemotherapy was gastrointestinal hematologic side-effects,and re-covered quickly with supportive treatment.No obvious Methotrexate induced neurotoxicity was found.Conclusion Based on high-dose chemotherapy,ITMTX can further improve the long-term survival of patients with relapsed medulloblas-toma,and it is more feasible and suitable for relapsed MB children in China.