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 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.

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.

Microscopic and histochemical methods were used to investigate flavonoids localization in the leaf and the stem of the Sarcandra glabra. The results indicated that flavonoids distributed mainly in epidermis, collenchyma, vascular bundles, secretory cells and palisade tissue of leaf. In the stem, they distributed mainly in epidermis, collenchyma, phloem and secretory cells. Histochemical localization of flavonoids using 5% solution of NaOH is convenient, rapid and reliable. The content of flavonoids in the leaf was higher those than in the stem. For sustainable utilization of the resources we suggested that only the leaves could be harvested.
Flavonoids ; metabolism ; Magnoliopsida ; metabolism ; Microscopy ; Plant Leaves ; metabolism ; Plant Stems ; metabolism

Objective:To explore the epidemiological characteristics of Streptococcus pyogenes, namely β-hemolytic Group A Streptococcus (GAS) in children in Shenzhen. Methods:Multilocus sequence typing (MLST) data on the epidemic clonal population of GAS infection in children in Shenzhen Children′s Hospital from January 2016 to December 2018 were retrospectively analyzed.In the present study, 32 GAS strains belonging to 7 different emm types were from 32 children′s with impetigo, cellulitis, scarlet fever, sepsis, pneumonia, obstructive sleep apnea hypopnea syndrome, bronchitis, allergy with rhinitis, buttock abscess, allergic purpura or pharyngeal tonsillitis, which were isolated from 23 throat swabs, 5 sputum samples, 3 pus and 1 blood.Using polymerase chain reaction technology, 7 pairs of allelic housekeeping genes ( gki, gtr, murI, mutS, recP, xpt and yqiL) of 32 GAS isolates were analyzed, and the target gene products were subjected to sequencing.Then the obtained gene sequences of each allele were submitted to the MLST database to obtain the allele profile.Finally, the allele profiles were introduced in the MLST database again to confirm the sequence typing (ST). Results:The GAS clone groups of emm 1.00 and its subtypes, emm 4.00, emm 12.00 and its subtypes, emm 22.00, emm 28.00, emm 75.00, and emm 89.00 belonged to the sequence typing ST28, ST39, ST36, ST46, ST52, ST49, and ST921, respectively. Conclusions:From 2016 to 2018, the MLST clone populations of GAS isolates causing infections in children in Shenzhen are classified as ST28, ST39, ST36, ST46, ST52, ST49 and ST921.

Objective:To investigate the correlation of the emm genotypes and virulence genes with the isolation sites of Group A Streptococcus (GAS). Methods:It was a retrospective study.The specimens were collected from children with impetigo in Beijing Children′s Hospital, Capital Medical University from 2006 to 2008 for GAS isolation and identification.A total of 24 GAS strains were isolated from 16 children with impetigo, among which 7 pairs of strains were isolated from the throat and skin of 7 children, and 1 pair of strains was isolated from the vulva and skin of one child, and the remaining 8 GAS strains were isolated from the skin pus samples of 8 children.Polymerase chain reaction was applied to detect the emm genotypes and 13 virulence genes ( speA, speB, speC, speF, speG, speH, speI, speJ, speK, speL, speM, smeZ and ssa). The correlation of the emm genotypes and virulence genes with the isolation sites of GAS strains was analyzed. Results:In this study, four emm genotypes were detected, including emm1.0 (15/24), emm12.0 (4/24), emm22.0 (2/24) and emm160.0 (1/24), and one subtype emm12.19 (2/24) was detected as well.The carrying rates of 13 virulence genes speA, speB, speC, speF, speG, speH, speI, speJ, speK, speL, speM, smeZ and ssa were 58.3%, 100%, 91.7%, 100%, 50.0%, 12.5%, 54.2%, 66.7%, 16.7%, 25.0%, 12.5%, 100% and 91.7%, respectively.All strains carried 5 to 11 virulence genes and they all carried speB, speF and smeZ.There were significant differences in the carrying rate of speA and speJ among the strains with different emm genotypes (all P<0.05). There was no significant difference in the distribution of virulence genes between skin isolates and pharyngeal isolates, including the 5 pairs of strains carrying the emm1.0 genotype (all P>0.05). Conclusions:The distribution of virulence gene of GAS in children with impetigo is significantly correlated with the emm genotype, rather than the isolation site.

Group A Streptococcus (GAS) is a very important pathogen, especially for children.On a global scale, GAS is an important cause of morbidity and mortality.But the burden of disease caused by GAS is still unknown in China and also has not obtained enough attention.For this purpose, the expert consensus is comprehensively described in diagnosis, treatment and prevention of GAS diseases in children, covering related aspects of pneumology, infectiology, immunology, microbiology, cardiology, nephrology, critical care medicine and preventive medicine.Accordingly, the consensus document was intended to improve management strategies of GAS disease in Chinese children.