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Objective: To understand the relationship between female breast cancer and occupational risk factors in Beijing, and provide scientific basis for the formulation of prevention strategies and measures. Methods: From June to December 2019, A 1: 1 case-control study was adopted, eight medical institutions in Beijing were selected as the research objects. Patients with breast cancer diagnosed by medical institutions were selected as case group and non breast cancer patients in the same medical institution as control group. A total of 973 subjects were included, including 495 in the case group and 478 in the control group. A one-to-one survey was conducted using a questionnaire uniformly compiled by the Beijing Centers for Disease Control and Prevention. The survey content mainly includes basic demographic characteristics and occupational risk factors. The Trait Coping Style Questionnaire (TCSQ) was used to investigate the corresponding methods, including two aspects: positive coping and negative coping. First, chi square test or Wilcoxon rank sum test were used for univariate analysis. Then Lasso regression was used to screen the risk factors of breast cancer. Finally, the risk factors were screened by multivariate logistic regression analysis. Results: Education lovel was 49.64%, body mass index (BMI) was 18.4~23.9 kg/m(2), accounting for 48.82%, marital status ws 84.48%. Compared with no night shift history, there was a significant increase in risk of breast cancer at night shift history (OR=1.70, 95% CI: 1.25~2.30, P<0.05) . Compared with most of the sitting posture and sometimes standing, the risk of breast cancer was increased, and the difference was statistically significant (OR=2.01, 95%CI: 1.40~2.90, P<0.05) . Conclusion: In the occupation risk factors, night shift work and working posture are related to the incidence of breast cancer in women, establishing a good schedule and avoiding long standing can effectively prevent and reduce the occurrence of breast cancer.
Subject(s)
Female , Humans , Beijing , Breast Neoplasms/epidemiology , Case-Control Studies , Logistic Models , Risk FactorsABSTRACT
OBJECTIVE: To analyze the active surveillance results of occupational pneumoconiosis(hereinafter referred to as “pneumoconiosis”) in Beijing in 2019. METHODS: A total of 2 634 dust exposed workers were recruited as the active surveillance subjects by judgment sampling method. The abnormalities and influencing factors of High kV or digital photography of posterior-anterior chest radiography(hereinafter referred to as “chest radiography”) and lung function were analyzed. RESULTS: The detection rate of abnormal chest radiograph and pulmonary dysfunction were 14.0%(368/2 634) and 6.6%(175/2 634), respectively. The multivariate logistic regression analysis showed that the risk of abnormal chest radiograph in dust-exposed workers increased with age(P<0.01). Mining and construction workers had higher risk of abnormal chest radiograph than manufacturers(all P<0.05). The risk of abnormal chest radiograph of dusk-exposed workers in state-owned and foreign enterprises was higher than that of workers in private enterprises(P<0.05). The risk of pulmonary dysfunction was increased with age and length of dust exposure(all P<0.05). Workers exposed to silica dust and aluminum dust had higher risks than those exposed to welding dust(all P<0.01). The risk of pulmonary dysfunction of workers in small and micro enterprises was higher than that of workers in large enterprises(all P<0.01). Mining workers had higher risks of pulmonary dysfunction than manufacturing workers(P<0.05). CONCLUSION: Age, length of dust exposure, dust type, industry type, enterprise scale and economic type were the influencing factors of lung injury of dust exposed workers. Therefore, the supervision of key population and industries should be strengthened to reduce the occurrence of pneumoconiosis.
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Objective@#To evaluate the mental health of female doctors and nurses.@*Methods@#Investigat the psychologic status of female doctors and nurses using symptom checklist 90. And statistical software was applied to analyze results of symptom checklist 90.@*Results@#There were differences in the score of SCL-90 between doctor and nurse groups, the difference was statistically significant (P<0.05) . Negative life events (OR=2.940) , relative suffer from mental illness (OR=3.683) , shift work (OR=1.611) and heavy workload (OR=2.265) were found to risk factors for the positive of SCL-90.@*Conclusion@#There were differences in the score of SCL-90 between doctor and nurse groups. Negative life events, relative suffer from mental illness, shift workand heavy workload are risk factors for SCL-90 positive of female doctors and nurses.
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Objective@#To investigate the status of abnormal menstruation in female nurses in a comprehensive hospital in Beijing, China and related influencing factors.@*Methods@#In July 2016, a cross-sectional survey was performed, and a self-administered questionnaire was used to investigate the status of menstruation and occupation in female nurses in a comprehensive hospital in Beijing. The chi-square test and a multivariate logistic regression analysis were used for statistical analysis.@*Results@#A total of 892 female nurses were investigated, and among them, 485 experienced abnormal menstruation within the past three months, resulting in an abnormal menstruation rate of 54.37%. The female nurses who were exposed to harmful factors during work, negative life events, or high workload had a significantly higher abnormal menstruation rate than those who were not exposed to such factors (χ2=5.199, 16.186, and 10.227, P<0.05 or P<0.01) . Negative life events (odds ratio [OR]=1.813, 95% confidence interval[CI]: 1.317-2.496) and high workload (OR=1.461, 95%CI: 1.112-1.918) were risk factors for abnormal menstruation.@*Conclusion@#Nurses have an abnormal menstruation rate as high as 54.37%, and high workload and negative life events were risk factors for abnormal menstruation in nurses.
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Objective@#To investigate the application of Symptom Checklist-90 (SCL-90) in Chinese nurses.@*Methods@#We performed a literature search for articles in Chinese on the mental health of nurses investigated using the SCL-90 that were published from January 2007 to December 2016. A total of 129 articles were included, involving 178 groups of valid samples as well as 36316 subjects in 27 provinces or cities in China. The metafor package of R 3.2.1 software and Excel were used for meta-analysis and data statistics.@*Results@#Heterogeneity was identified for the nine factors included in the literature data (Q test: P<0.05; I2 test >40%) , so a random effects model was used. For all factors except interpersonal relationship factor, the 95% confidence intervals of the pooled effect sizes did not include 0. For all factors except interpersonal relationship factor (Egger test: P<0.05) , no significant asymmetry or incompleteness appeared in the funnel plots. The fail-safe number of each factor was much larger than 5k+10. The merger scores and mean values of nine factors were higher than the national norm.@*Conclusion@#The SCL-90 is widely used in the study of mental status of Chinese nurses, but the SCL-90 norm for nurses is lacking.
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Objective@#To investigate the prevalence of reproductive system diseases among female workers in a city and related occupational influencing factors.@*Methods@#From June to September, 2016, a cross-sectional survey was used to select 9 944 female workers from six districts of Beijing and then a face-to-face questionnaire survey was performed. Univariate analysis using chi-square test and multivariate logistic regression analysis were used to investigate the risk factors for reproductive system diseases.@*Results@#The age of 9944 female workers ranged from 18 to 65 years (mean 35.53±9.52 years) , and among them, 7 351 (73.92%) were married. The overall prevalence rate of reproductive system diseases among these 9944 female workers during the past three months was 28.29%, and the prevalence rates of hyperplasia of mammary glands, vaginitis, and hysteromyoma were 15.54%, 11.25%, and 6.77%, respectively. After adjustment for age, marital status, education level, and annual family income, the multivariate logistic regression analysis showed that frequent overtime work (odds ratio[OR]=1.119, 95% confidence interval[CI]: 1.070-1.343) , frequent night shifts (OR=1.198, 95%CI: 1.054-1.361) , standing for a long time (OR=1.197, 95%CI: 1.063-1.347) , sitting for a long time (OR=1.327, 95%CI: 1.191-1.479) , heavy workload (OR=1.429, 95%CI: 1.262-1.615) , exposure to lead (OR=1.696, 95%CI: 1.307-2.201) , exposure to mercury (OR=1.452, 95%CI: 1.086-1.940) , and exposure to ionizing radiation (OR=1.679, 95%CI: 1.424-1.980) were associated with reproductive system diseases.@*Conclusion@#The prevalence of reproductive system diseases among female workers in Beijing is not optimistic. Reproductive system diseases are associated with frequent overtime work, frequent night shifts, standing for a long time, sitting for a long time, heavy workload, and exposure to lead, mercury, and ionizing radiation.
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Objective@#To evaluate the mental health of occupational females in different industries.@*Methods@#We investigated the psychologic status of Chinese occupational females using symptom checklist 90. And statistical software was applied to analyze results of symptom checklist 90.@*Results@#There were 41, 166 effec-tive questionnaires. The number of positive questionnaires was 14 361, and the positive rate was 34.89%. The positive rate of obsessive-compulsive factor was 24.07%. The positive rate of somatization factor was 16.12%. The positive rate of depression was 15.50%. The median positive item number was 20 (IQR: 34) , and the median split of positive symptoms was 2.11 (IQR: 0.37) . There were differences in the positive rate of SCL-90 scale among different age groups, different regions and different industries, the difference was statistically significant (P<0.05) . The positive rate of SCL-90 for the occupational females was 34.89%. The top three factors of the high-est positive SCL-90 were obsessive-compulsive symptoms, somatization and depression.@*Conclusion@#There were differences in the psychological status of occupational females for different regions, different ages and different occupations.
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Radioiodine ablation (RIA) therapy is one of the most important treatments for papillary thyroid carcinoma (PTC), but some patients who received (131)I have radioiodine-refractory disease caused by the decreased expression of the Na(+)/I(-) symporter (NIS). BRAF(V600E) mutation is one possible risk factor that can disturb the NIS expression, but the roles are unclear in clinical practice. This research discussed the association of BRAF(V600E) mutation and NIS expression in PTC tissue and the clinical implications in RIA therapy. 134 PTC samples were collected between June 2013 and June 2014 from Tongji Hospital affiliated to Tongji Medical College, and their clinical characteristics were analyzed. RT-PCR was used to detect the BRAF(V600E) mutation from formalin-fixed paraffin-embedded samples, and immunohistochemistry was applied to detect the NIS expression. IPP software was used to calculate the relative expression quantity of NIS. We found that there was no significant correlation between the absorbance (A) values of NIS and clinicopathologic features in these cases, even thyroid stimulating hormone. BRAF(V600E) mutation showed inhibitory effect on the NIS expression without statistically significant difference in all PTC cases (β=-0.0195, P=0.085), but in the subgroup without hashimoto's thyroiditis (HT), BRAF(V600E) mutation could significantly inhibit the NIS expression (β=-0.0257, P=0.046). The results indicate that BRAF(V600E) mutation is correlated with a lower expression of NIS in PTCs without HT, suggesting the radioiodine-refractory effects during RIA therapy in these patients.
Subject(s)
Adult , Female , Humans , Male , Middle Aged , Carcinoma , Genetics , Metabolism , Carcinoma, Papillary , Case-Control Studies , Mutation, Missense , Proto-Oncogene Proteins B-raf , Genetics , Symporters , Genetics , Metabolism , Thyroid Neoplasms , Genetics , MetabolismABSTRACT
Radioiodine ablation (RIA) therapy is one of the most important treatments for papillary thyroid carcinoma (PTC), but some patients who received (131)I have radioiodine-refractory disease caused by the decreased expreβsion of the Na(+)/I(-) symporter (NIS). BRAF(V600E) mutation is one poβsible risk factor that can disturb the NIS expression, but the roles are unclear in clinical practice. This research discussed the association of BRAF(V600E) mutation and NIS expression in PTC tissue and the clinical implications in RIA therapy. 134 PTC samples were collected between June 2013 and June 2014 from Tongji Hospital affiliated to Tongji Medical College, and their clinical characteristics were analyzed. RT-PCR was used to detect the BRAF(V600E) mutation from formalin-fixed paraffin-embedded samples, and immunohistochemistry was applied to detect the NIS expression. IPP software was used to calculate the relative expression quantity of NIS. We found that there was no significant correlation between the absorbance (A) values of NIS and clinicopathologic features in these cases, even thyroid stimulating hormone. BRAF(V600E) mutation showed inhibitory effect on the NIS expression without statistically significant difference in all PTC cases (β=-0.0195, P=0.085), but in the subgroup without hashimoto's thyroiditis (HT), BRAF(V600E) mutation could significantly inhibit the NIS expression (β=-0.0257, P=0.046). The results indicate that BRAF(V600E) mutation is correlated with a lower expression of NIS in PTCs without HT, suggesting the radioiodine-refractory effects during RIA therapy in these patients.
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<p><b>OBJECTIVE</b>To explore the value of color doppler ultrasound examination of thyroid in occupational health care of radiation-exposed physicians.</p><p><b>METHODS</b>One hundred and thirty-four radiation-exposed physicians (observation group) and sixty-eight non-radiation-exposed physicians (control group) received color doppler ultrasound examination of thyroid using ALOKA SSD-4000 color doppler ultrasonic diagnostic apparatus, and the results were compared between the two groups.</p><p><b>RESULTS</b>The anteroposterior diameters of the left lobe, right lobe, and isthmus of the thyroid in the observation group were significantly larger than those in the control group (P < 0.01). Compared with the control group, the observation group had significantly larger internal diameters and peak blood flow velocities during systole of the right superior thyroid artery (P < 0.05, P < 0.05). There were no significant differences in detection rates of thyroid nodules and lymph nodes between the observation group and the control group (18.7% vs 13.2%, P > 0.05; 6.7% vs 1.5%, P > 0.05). The radiation-exposed physicians were exposed to low-dose ionizing radiation with a dose between 0.14 and 1.67 mSv/a.</p><p><b>CONCLUSION</b>The color doppler ultrasound examination of the thyroid can detect early changes in the thyroid of radiation-exposed physicians exposed to long-term and low-dose ionizing radiation.</p>
Subject(s)
Humans , Lymph Nodes , Occupational Exposure , Occupational Health , Physicians , Radiation Exposure , Radiation, Ionizing , Thyroid Gland , Diagnostic Imaging , Radiation Effects , Ultrasonography, Doppler, ColorABSTRACT
The roles of intermediate conductance Ca(2+)-activated K(+) channel (IKCa1) in the pathogenesis of hepatocellular carcinoma (HCC) were investigated. Immunohistochemistry and Western blotting were used to detect the expression of IKCa1 protein in 50 HCC and 20 para-carcinoma tissue samples. Real-time PCR was used to detect the transcription level of IKCa1 mRNA in 13 HCC and 11 para-carcinoma tissue samples. The MTT assay was used to measure the function of IKCa1 in human HCC cell line HepG2 in vitro. TRAM-34, a specific blocker of IKCa1, was used to intervene with the function of IKCa1. As compared with para-carcinoma tissue, an over-expression of IKCa1 protein was detected in HCC tissue samples (P<0.05). The mRNA expression level of IKCa1 in HCC tissues was 2.17 times higher than that in para-carcinoma tissues. The proliferation of HepG2 cells was suppressed by TRAM-34 (0.5, 1.0, 2.0 and 4.0 μmol/L) in vitro (P<0.05). Our results suggested that IKCa1 may play a role in the proliferation of human HCC, and IKCa1 blockers may represent a potential therapeutic strategy for HCC.
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The roles of intermediate conductance Ca(2+)-activated K(+) channel (IKCa1) in the pathogenesis of hepatocellular carcinoma (HCC) were investigated. Immunohistochemistry and Western blotting were used to detect the expression of IKCa1 protein in 50 HCC and 20 para-carcinoma tissue samples. Real-time PCR was used to detect the transcription level of IKCa1 mRNA in 13 HCC and 11 para-carcinoma tissue samples. The MTT assay was used to measure the function of IKCa1 in human HCC cell line HepG2 in vitro. TRAM-34, a specific blocker of IKCa1, was used to intervene with the function of IKCa1. As compared with para-carcinoma tissue, an over-expression of IKCa1 protein was detected in HCC tissue samples (P<0.05). The mRNA expression level of IKCa1 in HCC tissues was 2.17 times higher than that in para-carcinoma tissues. The proliferation of HepG2 cells was suppressed by TRAM-34 (0.5, 1.0, 2.0 and 4.0 μmol/L) in vitro (P<0.05). Our results suggested that IKCa1 may play a role in the proliferation of human HCC, and IKCa1 blockers may represent a potential therapeutic strategy for HCC.
Subject(s)
Humans , Calcium Channel Blockers , Pharmacology , Carcinoma, Hepatocellular , Pathology , Cell Proliferation , Hep G2 Cells , Intermediate-Conductance Calcium-Activated Potassium Channels , Metabolism , Ion Channel Gating , Liver Neoplasms , Pathology , Potassium , Metabolism , Pyrazoles , Pharmacology , Tumor Cells, CulturedABSTRACT
<p><b>OBJECTIVE</b>To investigate the molecular characteristics of methicillin-resistant Staphylococcus aureus (MRSA) isolates from Chinese children in seven cities.</p><p><b>METHOD</b>A total of 134 MRSA isolates were collected from nine hospitals. Multilocus sequence typing and spa typing were analyzed by polymerase chain reaction (PCR), and staphylococcal chromosomal cassette mec (SCCmec) type was analyzed by multiplex PCR. The Panton-Valentine leukocidin (pvl) gene was also detected.</p><p><b>RESULT</b>Most MRSA strains were isolated from pneumonia and skin and soft tissue infection (SSTIs) patients, accounting for 82.1%. Overall, 16 sequence types (STs) were obtained, and CC59 (51.7%) was found to be the most prevalent, which included ST 59 and ST 338, followed by ST239 (16.4%). SCCmec types II, III, IV, and V were also identified in the current study. SCCmec type IV was the most predominant type at 50.0%, followed by SCCmec type V at 23.9% and III at 23.9%. SCCmec subtypes IVa, IVc, and IVg were found among SCCmec type IV strains, whereas IVa was the main subtype at 77.6%. Twenty-six spa types were also identified, among which the predominant type was t437 (47.8%). The prevalence of pvl genes and the SCCmec type of strain was relevant, and the pvl gene positive rate was higher in SCCmec type IV and V-type strains than in SCCmec type II and III strains (58.6% vs. 14.3%, P < 0.05); there was a significant difference between them. In the strains isolated from pneumonia and SSTIs, ST59-MRSA-IVa(t437) was the predominant clone. There were five clones detected from the strains isolated from septicemia, with ST59-MRSA-IVa(t437) and ST59-MRSA-V(t437) as the main clones (57.1%). Various predominant clones existed in different regions. ST59-MRSA-IVa(t437) was the prevalent clone in the Guangzhou, Beijing, Chongqing, and Shenzhen areas, whereas ST239-MRSA-III(t037) was the prevalent clone in the Shanghai area. Fifty percent of the isolates from the Wenzhou area belonged to ST910-MRSA-V(t318), whereas three clinical strains isolated from the Shenyang region belonged to three different types.</p><p><b>CONCLUSION</b>The results indicate that MRSA isolates from Chinese children are largely associated with the ST59-MRSA-IV(t437) and ST239-MRSA-III(t037) clones. These two may belong to community-acquired MRSA and hospital-acquired ones, respectively. Different prevalent clones were detected in different diseases and different regions. Therefore, there is a need to conduct further research on clinical isolates, which can guide the choice of antibiotic treatment and the examination of MRSA prevalence.</p>
Subject(s)
Adolescent , Child , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Male , Bacterial Typing Techniques , China , Epidemiology , DNA, Bacterial , Genetics , Methicillin-Resistant Staphylococcus aureus , Classification , Genetics , Prevalence , Staphylococcal Infections , Epidemiology , MicrobiologyABSTRACT
<p><b>BACKGROUND</b>Despite the prevalence of Streptococcus pneumoniae serotype 19A, the molecular characteristics of this serotype are yet to be fully elucidated. The aim of this study was therefore to determine the homology of the serotype 19A in China.</p><p><b>METHODS</b>Pulsed-field gel electrophoresis and multilocus sequence typing were done to these forty-nine serotype 19A isolates to investigate the relationship between the strains prevalent in Beijing and other regions.</p><p><b>RESULTS</b>From 1997 to 2006, the percentage of serotype 19A isolates increased. The susceptibility rate to penicillin and amoxicillin decreased and the resistance rate to cefuroxime increased. ST320 was the most prevalent ST, followed by ST3546. There were six new STs identified in our study. The serotype 19A strains were classified into six different pulsed-field gel electrophoresis (PFGE) patterns. ST320, which was associated with two different PFGE patterns (A and D), accounted for 32 isolates, and ST3546, which was associated with two PFGE patterns (B and E), accounted for eight isolates.</p><p><b>CONCLUSIONS</b>From 2003 onwards, ST320 was the most common ST and the rate of resistance to cefuroxime increased significantly. Further long-term surveys of Streptococcus pneumoniae serotype 19A are required to monitor ST prevalence and antimicrobial resistance in this important human pathogen.</p>
Subject(s)
Child, Preschool , Humans , Infant , Infant, Newborn , China , Drug Resistance, Bacterial , Electrophoresis, Gel, Pulsed-Field , Molecular Epidemiology , Pneumococcal Infections , Drug Therapy , Microbiology , Serotyping , Streptococcus pneumoniae , Classification , Genetics , Time FactorsABSTRACT
<p><b>BACKGROUND</b>In the present study, we characterized multidrug-resistant Pseudomonas aeruginosa (MDRP) clinical isolates from a paediatric facility and investigated the types and features of the metallo-beta-lactamases (MBLs) produced by carbapenem-resistant strains.</p><p><b>METHODS</b>Four hundred and ninety-eight strains of Pseudomonas aeruginosa were isolated from patients at Beijing Children's Hospital between January 2005 and December 2006. The minimal inhibition concentrations (MICs) of the strains for 13 antibiotics were measured. A combination of the E test and PCR amplification/DNA sequencing was used to define the carbapenem-resistant strains.</p><p><b>RESULTS</b>We found that 24.1% (120/498) of the isolates were MDRP. The frequencies of resistance to imipenem and meropenem were 34.2% and 35.8%, respectively, and the MIC50 and MIC90 values for the two antibiotics were identical at 4 microg/ml and 32 microg/ml, respectively. The detection rate for carbapenem resistance was 49.2% (59/120). Among the 59 carbapenem-resistant Pseudomonas aeruginosa strains, 39 (66.1%) were positive for the MBL genotype; 35 (89.7%) strains carried the bla(IMP) gene and 4 (10.3%) strains carried the bla(VIM) gene. Neither bla(SPM) nor bla(GIM) was amplified from any of the 59 isolates. DNA sequencing revealed that IMP-1 was present in 35 IMP-producing isolates and VIM-2 was detected in four VIM-producing isolates.</p><p><b>CONCLUSIONS</b>These MDRP isolates exhibited high frequencies of resistance to carbapenems among clinical isolates from a paediatric facility in Beijing, China. The production of MBL appears to be an important mechanism for carbapenem resistance in Pseudomonas aeruginosa.</p>
Subject(s)
Child , Humans , Carbapenems , Pharmacology , Drug Resistance, Multiple, Bacterial , Microbial Sensitivity Tests , Pseudomonas aeruginosa , Sequence Analysis, DNA , beta-Lactamases , Classification , GeneticsABSTRACT
<p><b>OBJECTIVE</b>To investigate the antimicrobial resistance of Streptococcus pneumoniae (S.pneumoniae) isolated from Chinese children with pneumonia.</p><p><b>METHODS</b>Hypopharyngeal aspirate specimens were collected from hospitalized children with pneumonia who were admitted to the children's hospital located in Beijing, Shanghai, Guangzhou or Shanghai from February 16, 2006 to February 16, 2007. The minimum inhibitory concentration (MIC) of S.pneumoniae isolates against penicillin, amoxicillin, cefuroxime (sodium), ceftriaxone, erythromycin, vancomycin, ofloxacin and imipenem was determined by E-test method.</p><p><b>RESULTS</b>A total of 279 S.pneumoniae isolates were obtained. Eighty-six percent of the isolates were not susceptive to penicillin, and 23.3% was resistant to penicillin. The rate of susceptibility of the isolates to amoxicillin was 92.1%, and to cefuroxime and ceftriaxone was 19.0% and 75.3%, respectively. The isolates also showed a high susceptibility to vancomycin (99.6%) and ofloxacin (97.8%). Seventeen point six percent of the isolates were not susceptive to imipenem, and most of those were intermediate. Almost of all isolates were resistant to erythromycin. There were some distinct regional differences in the susceptibility to antimicrobials tested except for erythromycin, vancomycin and ofloxacin.</p><p><b>CONCLUSIONS</b>The S.pneumoniae isolates from Chinese children with pneumonia were susceptive to amoxicillin, vancomycin and ofloxacin, but were not susceptive or resistant to penicillin, cefuroxime and erythromycin. The isolates kept susceptibility to ceftriaxone and imipenem to a certain extent.</p>
Subject(s)
Child , Humans , Drug Resistance, Bacterial , Hospitalization , Microbial Sensitivity Tests , Streptococcus pneumoniaeABSTRACT
<p><b>OBJECTIVE</b>The present study was designed to investigate the situation of serotype distribution and beta-lactam antibiotics resistance of Streptococcus pneumoniae (S. pneumoniae) isolated from Chinese children, and to further understand the significance of vaccine for preventing infection caused by the bactria and controlling the resistance to antibiotics.</p><p><b>METHODS</b>Nasopharageal swab specimens were collected from randomly selected less than 5-year-old out-patients with upper respiratory infection in Beijing, Shanghai and Guangzhou, 2000 - 2002. Capsular typing was performed by the Quellung reaction tested using a simplified chessboard system for typing of S. pneumoniae. The coverage rate of the 7-valent pneumococcal conjugate vaccine (4, 6B, 9V, 14, 18C, 19F and 23F) was calculated. Antibiotic susceptibility was determined by E-test MIC method for beta-lactam antibiotics (penicillin, amoxicillin/clavulanic acid, cefaclor, cefuroxime and ceftriaxone).</p><p><b>RESULTS</b>Totally 625 pneumococcal strains were typed. Serogroup 19, including 121 strains, was the most frequent serogroup observed (19.4%). Other frequently observed serotypes/serogroups in decreasing order of frequency were serotype/serogroups 23 (15.4%), 6 (13.3%), 14 (6.6%) and 15 (4.3%). Of all these isolates, about 57.6% (360/625) were in the 7-valent conjugate vaccine. Only 1, 6 and 12 strains were serotypes/serogroups 4, 9 and 18, respectively. The coverage rate for the 7-valent vaccine of penicillin nonsusceptible S. pneumoniae (PNSP) was higher than penicillin susceptible S. pneumoniae (PSSP) (73.2% and 46.1%). Serogroups 19 and 23, without other serotypes/serogroups, were significantly associated with PNSP (serogroup 19 accounted for 29.1% of PNSP and 12.2% of PSSP; serogroup 23 accounted for 23.8% of PNSP to 9.2% of PSSP). Overall, 140 strains (22.4%) could not be typed by using the chessboard system, and 117 strains (18.7%) were identified as other 28 kinds of serotype/serogroup. The strains showed different resistance change for beta-lactam antibiotics according to different serotype/serogroup during the three years.</p><p><b>CONCLUSIONS</b>Serotype/Serogroup 19, 23, 6, 14 and 15 were the common types among the pneumococcal strains isolated from Chinese children. Serogroups 19 and 23 were significantly associated with PNSP. The 7-valent pneumococcal conjugate vaccine could cover most of the islotes.</p>
Subject(s)
Child, Preschool , Humans , China , Epidemiology , Drug Resistance, Multiple, Bacterial , Pneumococcal Infections , Epidemiology , Respiratory Tract Infections , Epidemiology , Microbiology , Serotyping , Streptococcus pneumoniae , ClassificationABSTRACT
<p><b>OBJECTIVE</b>To investigate the molecular epidemiology of the penicillin-nonsusceptible Streptococcus pneumoniae (PNSP) in Beijing, China.</p><p><b>METHODS</b>The resistant profile of 63 PNSP strains isolated from children with upper respiratory infection in the outpatient department from 2000 to 2002 was analyzed. The isolates were compared by detecting restriction fragment length polymorphism (RFLP) of the penicillin-binding protein (PBP) genes pbp1a, pbp2b and pbp2x and by applying chromosomal macrorestriction patterns detected by pulsed-field gel electrophoresis (PFGE).</p><p><b>RESULTS</b>Sixty-one (96.8%) out of the 63 PNSP strains were multidrug-resistant Streptococcus pneumoniae (Sp). Overall, 16 resistance profiles were found, 14 of which were multidrug resistant profiles. Seven (33.3%), 6 (24.0%) and 8 (47.1%) strains resistant to one of cephalosporins were respectively isolated in 2000, 2001 and 2002, indicating an increasing trend but without any statistical significance (chi(2) = 2.42, P > 0.05). The RFLP results showed 8, 9 and 18 genotypes of pbp1a, pbp2b and pbp2x, respectively. A total of 30 patterns were found according to the three pbps types. And clearly, the most common 5 patterns had main resistant profiles. In the mean time, 35 different PFGE types were elucidated and the 9 PFGE types, with each consisting of more than 2 strains, covered 59% (37/63) of all isolates. One of the 9 PFGE type included 2 strains, both possibly related to each other, but one of them was detected to be the same PFGE pattern with clones prevalent in Asia, Vietnam-19 serogroup, Singapore-19 serogroup, Taiwan-19 serogroup, and the other was the same as that in Korea-19 serogroup.</p><p><b>CONCLUSION</b>Multidrug resistance is very common among PNSP isolates in Beijing. The spread of a few multidrug resistant clones is an important factor for the prevalence of PNSP. It deserves the concern that the resistant clones spread in Asia have been found in Beijing.</p>
Subject(s)
Child, Preschool , Humans , Infant , China , Epidemiology , DNA, Bacterial , Genetics , Drug Resistance, Bacterial , Genetics , Genotype , Molecular Epidemiology , Penicillin Resistance , Genetics , Pneumococcal Infections , Epidemiology , Polymorphism, Restriction Fragment Length , Sequence Analysis, DNA , Streptococcus pneumoniae , Classification , GeneticsABSTRACT
<p><b>OBJECTIVE</b>Haemophilus (H.) influenzae is a gram-negative bacillus that is a common commensal organism of the human upper respiratory tract and an important cause of human diseases such as pneumonia, meningitis, septicemia, epiglottitis and cellulitis. Strains of H. influenzae are classified according to their capsular polysaccharide. There are six serotypes, designated as a through f. In addition, there are nonencapsulated strains. Although the type of infectious diseases caused by H. influenzae has changed considerably in recent years because of the widespread and routine immunization of children against type b H. influenzae (Hib), Hib remains an important pathogen. Ampicillin is the drug of choice for treating many infections caused by H. influenzae, but its usefulness has been compromised by the increasing prevalence of ampicillin-resistant strains. The continued monitoring of resistant strains by using genotyping methods may provide insights into the epidemiology of transmission. A molecular epidemiological study of ampicillin-resistant H. influenzae derived from nasopharyngeal swabs specimens of children less than 5 years of age with respiratory tract infection were investigated in this study.</p><p><b>METHODS</b>A total of 899 isolates were collected from Beijing, Shanghai, and Guangzhou during 2000-2003. Susceptibility to ampicillin was determined by using E-test. Ampicillin-resistant H. influenzae strains were selected according to National Committee for Clinical Laboratory Standards (NCCLS) 2002 breakpoints. Nested PCR method with primers specific for bexA gene and b capsulate type-specific gene was established. Genotyping by pulsed-field gel electrophoresis (PFGE) and multiplex PCR assay was performed for all ampicillin-resistant H. influenzae strains.</p><p><b>RESULTS</b>Seventy-four ampicillin-resistant H. influenzae strains were obtained. Two strains were positive by nested PCR, characterized as b genotype. The incidence of Hib in ampicillin-resistant H. influenzae strains was 2.7%; 38 genotypes were detected by PFGE. Detection of five types strains of clonal dissemination by PFGE accounted for 55.4% in all ampicillin-resistant H. influenzae strains. Among them eighteen H. influenzae strains belonged to one type, accounted for 24.3% in all ampicillin-resistant H. influenzae strains. Thirty one genotypes were identified by multiplex PCR assay for ampicillin-resistant H. influenzae. The identity ratio of PFGE and multiplex PCR was 63.5%.</p><p><b>CONCLUSION</b>In Beijing, Shanghai and Guangzhou areas 55.4% of ampicillin-resistant H. influenzae strains had clonal dissemination during the 4 years.</p>
Subject(s)
Child, Preschool , Humans , Ampicillin Resistance , Genetics , Anti-Bacterial Agents , Pharmacology , China , Epidemiology , DNA, Bacterial , Genetics , Drug Resistance, Bacterial , Genetics , Electrophoresis, Gel, Pulsed-Field , Genotype , Haemophilus Infections , Epidemiology , Microbiology , Haemophilus influenzae , Classification , Genetics , Microbial Sensitivity Tests , Molecular Epidemiology , Nasopharynx , Microbiology , Polymerase Chain Reaction , Respiratory Tract Infections , MicrobiologyABSTRACT
<p><b>OBJECTIVE</b>To know their real epidemiological histories in 1,091 probale cases of severe acute respiratory syndrome (SARS) without definite history of contact with SARS patients in the first survey.</p><p><b>METHODS</b>All the probable SARS cases until June 9, 2003 without definite history of contact with SARS patients in the first epidemiological survey were included in a re-survey with questionnaire. The second survey was carried out during June 9 to 30, 2003.</p><p><b>RESULTS</b>The results showed that history of contact with other SARS patients was obtained in 15.9% of 1 091 probale SRAS cases in the second survey, transmission of SARS to others was found in 10.5% of them, and source of infection in hospital was found in 46.5%. Comprehensive judgement based on epidemiological history showed that probale history of contact with SARS patients could be found in 72.9% of 1,091 probale cases of SARS in the second survey.</p><p><b>CONCLUSION</b>Source of infection could be found through additional survey in part of probale cases of SARS without it in initial epidemiological survey.</p>