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.

Objective:To evaluate inflammation early in the infarct zone and its dynamic changes after acute myocardial infarction (AMI) using 18F-FDG PET imaging, and analyze its relationship with left ventricular remodeling progression (LVRP). Methods:Sixteen Bama miniature pigs (4-6 months old, 8 females) were selected. AMI models were established by balloon occlusion of the left anterior descending artery. 18F-FDG PET imaging was performed before AMI and at days 1, 5, 8, and 14 post-AMI to evaluate the regional inflammation response. 18F-FDG SUV ratio (SUVR) and the percentage of uptake area of left ventricle (F-extent) in the infarct zone, and the SUVRs of the spleen and bone marrow, were measured. Echocardiography and 99Tc m-methoxyisobutylisonitrile(MIBI) SPECT myocardial perfusion imaging (MPI) were performed at the above time points and on day 28 post-AMI to assess left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), left ventricular ejection fraction (LVEF), and myocardial perfusion defect extent. The degree of LVRP at day 28 post-AMI was defined as ΔLVESV(%)=(LVESV AMI 28 d-LVESV AMI 1 d)/LVESV AMI 1 d×100%. Data were analyzed using repeated measures analysis of variance, Kruskal-Wallis rank sum test and Pearson correlation analysis. Results:Twelve pigs were successfully modeled and completed the study. Inflammation in the infarct zone persisted until day 14 post-AMI. The SUVR of the infarct zone pre-AMI and at days 1, 5, 8, and 14 post-AMI were 1.03±0.08, 3.49±1.06, 2.93±0.90, 2.38±0.76, and 1.63±0.62, respectively ( F=49.31, P<0.001). The F-extent values in the infarct zone pre-AMI and at days 1, 5, 8, and 14 post-AMI were 0, (40.08±12.46)%, (40.00±12.76)%, (31.08±12.82)%, and 16.50%(7.25%, 22.00%), respectively ( H=37.61, P=0.001). There were no significant differences in the SUVRs of bone marrow and spleen before and after AMI ( F values: 0.69 and 0.77, both P>0.05). At day 1 post-AMI, both SUVR and F-extent in the infarct zone were significantly correlated with LVRP ( r values: 0.82 and 0.70, P values: 0.001 and 0.035). Conclusions:18F-FDG PET imaging can be used to evaluate inflammation in the infarct area and its dynamic changes after AMI. Inflammation in the infarct area is severe at day 1, and then gradually decreases. The extent and severity of inflammation visible on 18F-FDG PET imaging 1 d after AMI are closely related to LVRP.

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 evaluate the left ventricular diastolic dyssynchrony (LVDD) and its influencing factors early after acute myocardial infarction (AMI) using phase analysis of SPECT gated myocardial perfusion imaging (GMPI).Methods:Bama miniature swines ( n=16) were subjected to establish AMI models. GMPI was performed before and 1 d after AMI to obtain the extent of myocardial perfusion defect (Extent, %) and left ventricular systolic dyssynchrony (LVSD)/LVDD parameters, namely the phase histogram bandwidth (PBW) and phase standard deviation (PSD). Meanwhile, left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), left ventricular ejection fraction (LVEF), and the ratio of early to late peak mitral diastolic flow (E/A) were obtained by echocardiography. Independent-sample t test, paired t test and Pearson correlation analysis were used to analyze the data. Results:Sixteen AMI swines were successfully created. Compared to baseline, Extent, LVEDV and LVESV significantly increased on 1 d after AMI ( t values: -11.14, -4.55, -6.12, all P<0.001), while LVEF and E/A significantly decreased ( t values: 10.16, 2.18, P<0.001, P=0.046). GMPI showed that the LVDD parameters PBW and PSD increased significantly on 1 d after AMI when compared to those at baseline((142.25±72.06)° vs (33.06±8.98)°, (56.15±26.71)° vs (12.51±5.13)°; t values: -6.11, -6.60, both P<0.001). There were significant differences between LVSD parameters and LVDD parameters (PBW: (109.06±62.40)° vs (142.25±72.06)°, PSD: (44.40±25.61)° vs (56.15±26.71)°; t values: -2.73, -2.20, P values: 0.016, 0.044). LVDD parameters PBW, PSD were negatively correlated with E/A after AMI ( r values: -0.569, -0.566, P values: 0.021, 0.022), and positively correlated with the Extent ( r values: 0.717, 0.634, P values: 0.002, 0.008). The phase analysis of SPECT GMPI to evaluate LVDD showed good intra-observer and inter-observe reproducibility (intraclass correlation coefficient (ICC): 0.953-0.984, all P<0.001). Conclusions:LVDD occurs early on 1 d after AMI, and can reflect left ventricular diastolic dysfunction. The Extent is correlated with LVDD significantly. Phase analysis of SPECT GMPI is an accurate method to evaluate LVDD and left ventricular diastolic function.

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.

Objective:To investigate the predictive value of 18F-fluorodeoxyglucose (FDG) PET/CT metabolic parameters for occult lymph node metastasis (OLM) in non-small cell lung cancer (NSCLC). Methods:A total of 183 patients (72 males, 111 females; age (61.5±8.4) years) who underwent 18F-FDG PET/CT and preoperatively diagnosed with clinical N0 stage (cN0) in Third Affiliated Hospital of Soochow University from January 2013 to December 2018 were retrospectively enrolled. All patients underwent anatomical pulmonary resection with systematic lymph node dissections within 3 weeks after 18F-FDG PET/CT examinations. According to the presence or absence of lymph node metastasis, patients were divided into OLM positive (OLM+ ) group and OLM negative (OLM-) group. Parameters of primary lesions, such as the maximum diameter (D max), tumor sites, morphological features, maximum standardized uptake value (SUV max), mean standardized uptake value (SUV mean), metabolic total volume (MTV), total lesion glycolysis (TLG), tumor SUV max to liver SUV mean (TLR max), tumor TLG to liver SUV mean (TLR TLG) were analyzed. Mann-Whitney U test and χ2 test were used to compare the parameters between groups. Multivariable logistic regression was used to analyze the independent risk factors for OLM. Receiver operating characteristic (ROC) curve analysis was used to evaluate the diagnostic value of different parameters. Results:Among 183 patients, 25 (13.7%, 25/183) of them were diagnosed as OLM. In OLM+ group, 46 lymph nodes were pathologically positive for metastasis, including 15 N1 disease and 31 N2 disease. D max (2.9(2.3, 3.7) vs 2.3(1.7, 2.8) cm), lobulation ((76.0%(19/25) vs 37.3%(59/158)), SUV max (11.1(7.9, 17.7) vs 4.7(2.3, 9.2)), TLG (41.5(10.2, 91.1) vs 15.6(6.5, 23.8) ml), TLR max (4.7(3.5, 7.6) vs 2.1(0.9, 4.0)) and TLR TLG (18.1(5.0, 44.3) vs 6.1(3.0, 11.4) ml) of the primary lesions in OLM+ group were significantly higher than those in OLM-group ( z values: from -4.709 to -3.247, χ2=13.190, all P<0.05). Multivariable logistic regression analysis showed that TLR max (odds ratio ( OR)=15.145, 95% CI: 3.381-67.830, P<0.001) and D max ( OR=3.220, 95% CI: 1.192-8.701, P=0.021) were independent risk factors for OLM. TLR max yielded the highest area under curve (AUC; AUC=0.794) with the threshold of 3.12, and the sensitivity, specificity, accuracy, positive predictive value and negative predictive value for predicting OLM were 92.0%(23/25), 63.3%(100/158), 67.2%(123/183), 28.4%(23/81) and 98.0%(100/102), respectively. Conclusions:TLR max of tumor is the independent risk factor for OLM in NSCLC patients. TLR max can sensitively predict OLM preoperatively in patients with NSCLC.

Objective: To investigate the relationship between the recurrence of benign paroxysmal positional vertigo(BPPV) and the levels of bone mineral density(BMD) and estrogen in postmenopausal women. Methods: A total of 38 postmenopausal women with recurrent BPPV were recruited as study group, in the First Affiliated Hospital of Soochow University from December 2013 to June 2017. Meanwhile, 49 normal menopausal women were included as control. All patients were natural menopausal for over one year.The patients were diagnosed as BPPV based on results of Dix-Hallpike test and Roll-test, with at least two episodes of recurrent onset. In the subjects, BMD was measured by dual X-ray absorptiometry of lumbar vertebrae. Estrogen levels were obtained by testing serum estradiol (E2) levels in early morning fasting venous blood. In the present study, we compared the level of E2 and the value of BMD in two groups by SPSS 21.0. In the study group, patients with decreased BMD were divided into two groups: treatment and untreated group. The recurrence rate of BPPV was compared between the two groups within 12 months. Results: ①The averagel levels of E2 and BMD in the study group were (16.21±11.00)ng/L and -1.68±0.98) respectively, which were significantly lower than those in the control group (t value was 7.03 and 8.05 respectively, both P<0.05). The averagel levels of E2 and BMD incontrol group were(28.52±6.34)ng/L and -0.18±0.77 respectively. ②The number of patients with decreased BMD in the study group (30 cases) was more than that in control group (6 cases), and the difference was statistically significant (P<0.05). ③ The recurrence rate of BPPV in treatment group [17.6%(3/17)] was significantly lower than that of untreated group [61.5%(8/13)], and the difference was statistically significant (P<0.05). Conclusion Recurrent BPPV in postmenopausal women usually accompany with low levels of estrogen and BMD. Active treatment is helpful for their recurrence of BPPV.

Objective To compare the different ways of alkaline mouthwash slobber use in preventing the oral infection in patients with fever. Methods The patients who satisfied the requirements were involved and randomly divided into A, B and C group. A group did not use alkaline mouthwash; B group prescribed alkaline mouthwash slobber following the doctor's advice; C group received propaganda and demonstration of intensive use of the alkaline mouthwash, and then used the slobber in right way under the surveillance of nurses. The infection rates of oral ulcer and oral leukoplakia were compared and analyzed among the three groups. Results The incidence rates of oral ulcer and oral leukoplakia gradually decreased among the three groups and the differences had statistical significance (χ2=9.243,P=0.010;χ2=6.495,P=0.033).Compared with A group, there was no significant differences in the rates of oral ulcers and oral leukoplakia between Group A and B(OR=0.486, 95%CI:0.113-2.087;OR=0.557, 95%CI: 0.120-2.583), but the incidence rates of oral ulcers and oral leukoplakia gradually decreased(OR=0.024, 95%CI:0.002-0.293;OR=0.036, 95%CI:0.003-0.448)in C group. Conclusions Strengthening use of alkaline mouthwash slobber is more effective in preventing oral infection in patients with fever compared with the routine way of mouthwash use.

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 the relative percentage of normal cognitive function (NCF),age associated memory impairment (AAMI),mild cognitive impairment (MCI) and Alzheimer's disease (AD) in the elderly,and the correlation between cognitive function and ApoE genotypes.Methods A total of 2666 elderly people aged ≥65 years (2132 males and 534 females)were divided into 3 groups according age:65-74-year age group (925 cases),75-84 year age group (1054 cases) and 85-100-year age group (687 cases).ApoE genotypes were determined in the controls and patients with AAMI and MCI.The degrees of fundus arteriosclerosis were detected in all subjects except for patients with AD.Results There were 867 cases with NCF,860 cases with AAMI and 782 cases with MCI.The incidence of AAMI was higher in 65-74-year age group than in the other two groups (42.0％ vs.31.1,20.96).The incidences of MCI and AD were higher in 85-100-year age group than in the other groups (42.5％,13.3％).The major degrees of fundus arteriosclerosis were Ⅰ+,Ⅰ-Ⅱ°,Ⅱ in subjects with AAMI (34.7％,x2=10.02,P＜0.01) and were Ⅱ °/ Ⅱ + / Ⅲ° in subjects with MCI (34.9 ％,x2 =23.39,P＜0.001).The APOEε4 allele frequency was significantly higher in patients with MCI than in the controls (x2=8.31,P＜0.05).However,no significant differences in APOEε4 allele frequency were found between patients with AAMI and the controls.Conclusions The incidence of AAMI is highest in 65-74-year age group,while the incidences of MCI and AD are highest in 85-100-year age group.Compared to patients with AAMI,the more serious fundus arteriosclerosis and higher allele frequency of APOEε4 appear in patients with MCI.