Objective To report the clinical characteristics of prosthetic valve endocarditis (PVE).Methods All 25 cases of definite PVE (Duke criteria) diagnosed at our hospital between January 1992 to December 2008 were retrospectively analyzed. Among them, 7 cases were pathologically confirmed and the others were clinically confirmed with either 2 major criteria or 1 major and ≥3 minor criteria. Their clinical characteristics, underlying heart diseases, previous heart operations, presenting manifestations, causative microbes, echocardiographic findings and prognosis, were studied. Results (1) Although most cases underwent valve transplantations for underlying heart diseases of rheumatic heart diseases and congenital heart diseases, 10 patients were complicated with infectious endocarditis (IE) prior to the operations, 4 of them were PVE. (2) Eleven of them developed PVE within 2 months postoperatively. Fever (100%),major vessel embolism (48%), and anemia (36%) were the most frequently manifestations. Fourteen cases (56%) had positive culture results with 15 causative pathogens, including 5 coagulase-negative Staphylococcus (CNS, 3 were methicillin-resistant coagulase-negative Staphylococcus, MRSCoN), 4 fungi, 2Enterococcus faecalis, 2 Burkholderia cepacia, 1 Stenotrophomonasmal-tophilia, and 1 Streptococcus.(3)Prosthetic valve vegetations, periannular leakage, regurgitation, were the main echocardiographic findings.Transesophageal echocardiography (TEE) revealed 13 PVE who had no positive findings on previous transthoracic echocardiography (TTE). (4) Eighteen PVE (72%) developed peri-annular complications (12 leakage, 3 dehiscence, 2 abscesses, 1 fistula), major vessel embolism, congestive heart failure (16%) were frequently observed, 9 of the 17 patients died in hospital, in spite of intensive managements.Conclusions PVE has a high mortality and is a severe complication for patients who underwent heart surgery. Its causative pathogen spectrum is quite different from that of native valve endocarditis. TTE is not sensitive for some PVE cases.

OBJECTIVE: To investigate the correlation of mental workload and prevalence of work-related musculoskeletal disorders musculoskeletal disorders( WMSDs) in railway vehicle manufacturing workers.METHODS: A total of 362 male workers in assembling and welding workshop from a railway vehicle manufacturing enterprise were selected as study subjects by cluster sampling method.The level of mental workload and prevalence of WMSDs were investigated using a revised Subjective Workload Assessment Technique and China Musculoskeletal Questionnaire.RESULTS: The median score of mental workload was 67 and the prevalence rate of WMSDs was 56.9%.The multivariate logistic regression analysis results indicated that the higher the mental workload of railway vehicle manufacturers,the higher their risk for WMSDs after excluding the influence of confounding factors( P < 0.05).Workers in welding work showed a higher risk than those in assembling work( P < 0.01).Workers with fast work rhythm showed higher risk of WMSDs than those with regular working rhythm( P < 0.01).Workers with comfortable working environment and temperature showed lower risk of WMSDs than those with uncomfortable working environment and temperature( P < 0.01).CONCLUSION: The mental workload can increase the risk of WMSDs,with a dose-effect relationship in railway vehicle manufacturing workers.The type of work,work frequency and the temperature in working environment are also influencing factors of WMSDs.

OBJECTIVE: To compile the Chinese Musculoskeletal Questionnaire(CMQ) and test its reliability and validity. METHODS: The initial CMQ was formed through studying literatures, interviewing professional workers who have work-related musculoskeletal disorders(WMSDs) and investigation with occupational health and ergonomics experts. Then, 436 and 443 manufacturing workers were selected as prediction and verification samples respectively by convensence sampling method. The reliability and validity of the CMQ were tested by item analysis, exploratory factor analysis and confirmatory factor analysis. RESULTS: i) The CMQ composed of 48 items with item analysis. ii) Nine common factors of CMQ were extracted using exploratory factor analysis, which explained 70.721% of WMSDs variance. iii) The results of confirmatory factor analysis showed that the ratio of chi-square to degree of freedom was 3.380, the comparative fit index was 0.781, the Tucker-Lewis index was 0.764, the root mean square error of approximation was 0.073, and the standardized root mean square residual was 0.068. iv) The results showed that the item reliabilities of the 9 common factors of CMQ such as upper and lower limbs posture load, neck posture load, back posture load, job demand, social support, job control, job environment, job system and job facilities were 0.205-0.841, the composite reliabilities were 0.545-0.894, and the convergence efficiencies were 0.377-0.834. The correlation coefficients between the common factors were less than its square root of the convergence validities. CONCLUSION: The CMQ has good reliability and validity, and is a reliable and effective tool for evaluating WMSDs.

OBJECTIVE: To analyze the prevalence and influencing factors of multisite work-related musculoskeletal disorders(WMSDs) of workers in a railway vehicle manufacturing enterprise. METHODS: A total of 366 male workers in the assembly and riveting workshop of a railway vehicle manufacturing enterprise were selected as the research subjects using the cluster sampling method. The Chinese Musculoskeletal Questionnaire was used to investigate the prevalence of multiple sites of WMSDs. Multiple logistic regression analysis was used to analyze the influencing factors. RESULTS: The total prevalence of WMSDs was 56.3%(206/366). The prevalence of WMSDs in all parts from high to low was as follows: lower back(35.5%), hand and wrist(27.6%), neck(23.2%), shoulder(21.0%), knee(19.9%), upper back(18.6%), hip and leg(18.0%), ankle/foot(15.8%) and elbow(12.3%)(P<0.01). The total prevalence of multisite WMSDs was 38.0%(139/366). The prevalence of WMSDs in different numbers of parts from high to low was as follows: 6 or more parts(12.0%), 2 parts(10.7%), 3 parts(6.6%), 5 parts(5.5%) and 4 parts(3.3%)(P<0.01). Multiple logistic regression analysis results showed that the overweight and obese workers had higher risk of multi site WMSDs than those with normal body mass index(P<0.05).Those with long-term low heads, frequent bending, long bending of the elbows, and higher frequency of work requirements, and less frequently communicated with the leader had higher risk of multi site WMSDs(P<0.05). CONCLUSION: The prevalence of multisite WMSDs in railway vehicle manufacturing enterprise is relatively high. The influencing factors include individual factors, adverse ergonomic factors and psychosocial factors.