Screening of pathogenic molecular markers of Staphylococcus aureus in children based on whole genome sequencing technology / 中国当代儿科杂志

OBJECTIVES@#To explore the molecular characteristics of Staphylococcus aureus (S. aureus) in children, and to compare the molecular characteristics of different types of strains (infection and colonization strains) so as to reveal pathogenic molecular markers of S. aureus.@*METHODS@#A cross-sectional study design was used to conduct nasopharyngeal swab sampling from healthy children in the community and clinical samples from infected children in the hospital. Whole genome sequencing was used to detect antibiotic resistance genes and virulence genes. A random forest method to used to screen pathogenic markers.@*RESULTS@#A total of 512 S. aureus strains were detected, including 272 infection strains and 240 colonization strains. For virulence genes, the carrying rates of enterotoxin genes (seb and sep), extracellular enzyme coding genes (splA, splB, splE and edinC), leukocytotoxin genes (lukD, lukE, lukF-PV and lukS-PV) and epidermal exfoliating genes (eta and etb) in infection strains were higher than those in colonization strains. But the carrying rates of enterotoxin genes (sec, sec3, seg, seh, sei, sel, sem, sen, seo and seu) were lower in infection strains than in colonization strains (P<0.05). For antibiotic resistance genes, the carrying rates of lnuA, lnuG, aadD, tetK and dfrG were significantly higher in infection strains than in colonization strains (P<0.05). The accuracy of cross-validation of the random forest model for screening pathogenic markers of S. aureus before and after screening was 69% and 68%, respectively, and the area under the curve was 0.75 and 0.70, respectively. The random forest model finally screened out 16 pathogenic markers (sem, etb, splE, sep, ser, mecA, lnuA, sea, blaZ, cat(pC233), blaTEm-1A, aph(3')-III, ermB, ermA, ant(9)-Ia and ant(6)-Ia). The top five variables in the variable importance ranking were sem (OR=0.40), etb (OR=3.95), splE (OR=1.68), sep (OR=3.97), and ser (OR=1.68).@*CONCLUSIONS@#The random forest model can screen out pathogenic markers of S. aureus and exhibits a superior predictive performance, providing genetic evidence for tracing highly pathogenic S. aureus and conducting precise targeted interventions.

Dose-response relationship between age and Streptococcus pneumoniae vaccination coverage in kindergarten children / 中国当代儿科杂志

OBJECTIVES@#To investigate the potential relationship between age and Streptococcus pneumoniae vaccination coverage in kindergarten children, and to provide a basis for guiding vaccination and developing new protein vaccines.@*METHODS@#The stratified cluster random sampling method was used to select 1 830 healthy children from six kindergartens in Shunde District, Foshan City, China, and nasopharyngeal swabs were collected for the isolation and identification of Streptococcus pneumoniae. The logistic regression model based on restricted cubic spline was used to analyze the dose-response relationship between age and Streptococcus pneumoniae vaccination coverage.@*RESULTS@#The rate of nasal Streptococcus pneumoniae carriage was 22.46% (411/1 830) among the kindergarten children, with the predominant serotypes of 6B, 19F, 15A, 23A, 34, and 23F. The coverage rates of 10-valent pneumococcal conjugate vaccine (PCV10) and 13-valent pneumococcal conjugate vaccine (PCV13) were 53.0% and 57.9%, respectively, and there was a significant non-linear dose-response relationship between age and the coverage rates of PCV10 and PCV13 (P<0.05), with a higher coverage rate of PCV10 (88.0%) and PCV13 (91.1%) in the children aged 2 years. There was a significant non-linear dose-response relationship between age and the coverage rates of pilus islet 1 (PI-1) and pilus islet 2 (PI-2) (P<0.05), with a lower vaccination coverage rate for PI-1 (37.7%) and PI-2 (16.1%). The coverage rates of PI-1 (13.0%-58.5%) and PI-2 (6.0%-29.4%) were lower in all age groups. The virulence genes lytA (99.5%) and ply (99.0%) associated with candidate protein vaccines showed higher vaccination coverage rates.@*CONCLUSIONS@#There is a significant non-linear dose-response relationship between the age of kindergarten children and the coverage rates of PCV10 and PCV13 serotypes, and kindergarten children aged 2 years have a relatively high coverage rate of PCV. The high prevalence of the virulence genes lytA and ply shows that they are expected to become candidate virulence factors for the development of a new generation of recombinant protein vaccines.

Clinical features of children with periodic fever, aphthous stomatitis, pharyngitis, and adenitis syndrome: an analysis of 13 cases / 中国当代儿科杂志

OBJECTIVE@#To study the clinical features of children with periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome, a polygenic and multifactorial autoinflammatory disease with unknown pathogenesis.@*METHODS@#A retrospective analysis was performed on the medical data of 13 children with PFAPA syndrome.@*RESULTS@#All 13 children had disease onset within the age of 3 years, with a mean age of onset of (14±10) months. They all had periodic fever, with 8-18 attacks each year. The mean interictal period of fever was (30±5) days. Pharyngitis, cervical adenitis, and aphthous stomatitis were the three cardinal symptoms, with incidence rates of 100% (13/13), 85% (11/13), and 38% (5/13) respectively. There were increases in white blood cells, C-reactive protein, and erythrocyte sedimentation rate during fever. Of all the 13 children, 6 underwent whole exome sequencing and 7 underwent panel gene detection for autoinflammatory disease, and the results showed single heterozygous mutations in the @*CONCLUSIONS@#For children with unexplained periodic fever with early onset accompanied by pharyngitis, cervical adenitis, aphthous stomatitis, elevated inflammatory indices, and good response to glucocorticoids, PFAPA syndrome should be considered. This disorder has good prognosis, and early diagnosis can avoid the long-term repeated use of antibiotics.

Clinical features of patients with pulmonary thromboembolism complicated by hemoptysis and the prognosis analysis during hospital stay / 中国实用内科杂志

OBJECTIVE: To analyze the clinical feature and prognosis during hospitalization of pulmonary thromboembolism(PTE) patients with hemoptysis. METHODS: Between January 2010 and January 2015, a total of 220 patients diagnosed with acute PTE were recruited in our study in Beijing Hospital. Baseline characteristics, clinical signs and symptoms, laboratory tests, imaging findings, therapy and hospitalization outcomes(including mortality, and incidences of bleeding events) were collected. All the patients were divided into two groups according to whether hemoptysis occurred. A variety of clinical parameters in clinical features and prognosis were compared between the two groups.RESULTS: Among 220 patients, 16(7.3%) had hemoptysis and 204(92.7%) did not. Hemoptysis group were significantly younger [(59.7±16.6)vs.(67.2±13.6) years, P=0.037] and there were more males(75.0% vs. 44.6%, P=0.034). Compared to patients without hemoptysis, those with hemoptysis had a higher incidence of fever(31.3% vs. 11.3%, P=0.037) and chest pain(50.0% vs. 26.0%; P=0.039). The average diagnosis time of hemoptysis group was(8.91 ± 6.09) days. Patients in the hemoptysis group had a higher proportion of inferior vena cava filter(IVCF)(18.8%vs. 3.4%, P=0.028). There was no significant difference in severity and in-hospital mortality between the two groups. CONCLUSION: The lack of specificity of hemoptysis caused by PTE often leads to misdiagnosis or delayed diagnosis. Early diagnosis is helpful to correct treatment and reduce the adverse consequences of improper measures.

Using multivariate multilevel logistic model to study the influential factors of attitudes related to the Punishment on Smoking, among the residents in Guangzhou / 中华流行病学杂志

Objective To explore the attitudes towards the Smoking Ban policy and the bias in different levels of related society sanctions so as to provide evidence for implementing anti-smoking measures in the public places.Methods A multi-univariate-multilevel logistic model was developed to find the relation between penalty attitudes and the covariates' effects.Results 74.6％ (3647/4892) and 61.2％ (2994/4892) of the residents agreed to punish either the managers of public places or to the smokers.The two kinds of attitude were associated (x2 =1253.45,P＜0.0001 ).Residents being female,aged between thirty and fifty-nine years old,having had higher than college education,being non-current smokers,with high scores on knowledge of tobacco control,tended to have the attitude of punishing the public place managers and smokers.However,those persons exposed to everyday secondhand smoke or being non-current smokers,tended to punish the smokers in the generalized Wald test.Conclusion There was strong evidence noticed that most of the residents in Guangzhou had supported the ‘tobacco control penalty'.Factors as age,sex,level of education received,knowledge on hazards of smoking,being current smokers and under secondhand smoke exposure were the influencing factors.Non-current smokers and those who exposed to secondhand smoke everyday,would prefer to take different penalties policies.

Multivariate and multilevel model analysis on factors that influencing the literacy of health among high school students in Guangdong province / 中华流行病学杂志

Objective To analyze the awareness on health among high school students and its influencing factors in Guangdong. Methods Multi-stage sampling and questionnairs "2009 health awareness survey of the Chinese citizens" developed by our Department of Health, were used. Data were analyzed by multivariate multilevel model under MLwinN 2.19 software. Results The mean scores on knowledge and ideas, behaviors and related skills among 1606 high school students of Guangdong province, were 69.08 ± 14.81,60.05 ± 16.85 and 74.99 ± 21.17 respectively. Three items on health showed that they all related to each other and relations between grades (0.972,0.715 and 0.855) were greater than the individuals (0.565,0.426 and 0.438). Conclusion Factors as students from outside the Pearl River Delta region or from the rural areas, being male, at general secondary schools, at grade one, with poor academic performance and more pocket money etc., had lower levels on those related information of health.

Evaluation of cirrhotic liver with perfusion-weighted magnetic resonance imaging: a preliminary experimental study in animal models with half-liver cirrhosis / 中国医学科学杂志(英文版)

<p><b>OBJECTIVE</b>To investigate the role of perfusion-weighted magnetic resonance imaging (MRI) in evaluation of cirrhotic liver.</p><p><b>METHODS</b>With a 4F catheter, 1% diluted carbon tetrachloride (1 ml/kg) was selectively injected into right or left hepatic artery of 12 dogs fortnightly. The half liver into which carbon tetrachloride was injected was called as study side (SS), while the other half liver without carbon tetrachloride injection was called as study control side (SCS). Conventional and perfusion-weighted MRI were performed in every 4 weeks. Via a 4F catheter, 5ml gadolinium diethylentriamine pentaaceti acid (Gd-DTPA) dilution was injected into superior mesenteric artery at the 5th scan. The signal intensity-time curves of SS, SCS, and portal vein were completed in MR workstation. The maximal relative signal increase (MRSI), peak time (tp), and slope of the curves were measured.</p><p><b>RESULTS</b>On conventional MR images, no abnormalities of externality and signal intensity were observed in both SS and SCS of liver at each stage. The mean tp, MRSI, and slope of intensity-time curves in normal liver were 10.56 seconds, 1.01, and 10.23 arbitrary unit (au)/s, respectively. Three parameters of curves didn't show obvious change in SCS of liver at every stage. Abnormal perfusion curves occurred in SS of liver at the 12th week after the 1st injection. The abnormality of perfusion curve in SS was more and more serious as the times of injection increased. The mean tp, MRSI, and slope intensity-time curves in SS of liver were 19.45 seconds, 0.43, and 3.60 au/s respectively at the 24th week.</p><p><b>CONCLUSION</b>Perfusion-weighted imaging can potentially provide information about portal perfusion of hepatic parenchyma, and to some degree, reflect the severity of cirrhosis.</p>

Imaging characteristics of autoimmune pancreatitis / 中华放射学杂志

Objective To investigate the imaging characteristics of autoimmune pancreatitis (AIP).Methods MR imaging was performed in 12 patients with AIP proved histopathologically or clinically,of them CT was scanned in 10 patients and endoscopic retrograde cholangiopancreatography (ERCP)in 3.All imaging data were reviewed retrospectively.Results All 12 patients had enlargement of the pancreas either diffusely(n=9)or focally(n=3).The swollen pancreas was hypointense on T_1-weighted images and mildly hyperintense on T_2-weighted images.It also demonstrated decreased enhancement on artery phase of dynamic imaging and moderate enhancement on delayed phase images. Capsule-like enhanced rim was found around the swollen pancreas in 11 patients.Stricture of the distal common bile duct was found in 9 patients,and ERCP showed diffuse and irregular narrowing of the main pancreatic duct in 3 cases.At follow-up,pancreatic abnormalities and common bile duct stricture resolved after steroid therapy in 7 patients.Conclusion AIP showed some characteristic imaging findings,and imaging examinations will play an important role in the diagnosis of AIP.