Relationship between perceptions of safety climate at workplace and depressive disorders in manufacturing workers / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the risk factors for depressive disorders in manufacturing workers and to provide a basis for developing health promotion measures at workplace.</p><p><b>METHODS</b>A questionnaire survey was performed in 8085 front-line production workers from 33 manufacturing enterprises in Nanhai District of Foshan, Guangdong Province, China. The questionnaire contained a survey of demographic characteristics, the Safety Climate Scale, the Center for Epidemiological Studies Depression Scale, etc. The multilevel logistic regression analysis was applied to investigate the risk factors for depressive disorders in workers.</p><p><b>RESULTS</b>A total of 6260 workers completed the survey; their mean age was 31.1 ± 8.6 years, and 53.2% of them were males. The multilevel logistic regression analysis showed that after adjustment for sociodemographic factors such as age, sex, and martial status, more depressive disorders were reported in the enterprises with higher score of "production safety training" than in those with lower score (OR = 1.46, 95%CI = 1.07 ∼ 1.97); fewer depressive disorders were reported in the enterprises with higher score of "colleagues concerned about production safety" than in those with lower score (OR = 0.08, 95%CI = 0.03 ∼ 0.26); the relationships of "safety warnings and precautions" and "managers concerned about production safety" with workers' depressive disorders were not statistically significant (OR = 0.78, 95%CI = 0.48 ∼ 1.28; OR = 1.08, 95%CI = 0.68 ∼ 1.72).</p><p><b>CONCLUSION</b>Depressive disorders in manufacturing workers are related to the safety climate at workplace, which indicates that a good safety climate at workplace should be created to prevent and control depressive disorders in workers.</p>

Associations of occupational safety atmosphere and behaviors with unintentional injuries / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To evaluate the associations of perception of safety atmosphere at workplace, occupational safety attitude and behaviors with occupational unintentional injury among manufacturing workers.</p><p><b>METHODS</b>A cross-sectional study was performed and a self-administered questionnaire was used to inquire socio-demographic characteristics, perceived safety atmosphere, occupational safety attitudes, occupational safety behaviors and occupational unintentional injuries among 10585 manufacturing workers selected from 46 enterprises in Guangdong. Structural equation modeling was applied to assess the relationship of the perception of safety atmosphere at workplace, occupational safety attitude, and occupational safety behaviors with occupational unintentional injury.</p><p><b>RESULTS</b>Among 24 pathways supposed in structural equation model, 20 pathways (except for the attitude toward occupational safety, the attitude toward managers' support, the work posture and individual protection) were significantly related to the occupational unintentional injuries. The further analysis indicated that the perceived safety atmosphere might impact the occupational unintentional injuries by the attitude toward occupational safety and occupational safety behaviors.</p><p><b>CONCLUSION</b>Workers' perception of safety atmosphere indirectly influenced on occupational unintentional injuries through occupational safety attitudes and occupational safety behaviors.</p>

Effects of neurotrophin 3 on interdigestive migrating motor complex in rats with acute liver injury / 南方医科大学学报

<p><b>OBJECTIVE</b>To observe the effects of neurotrophin 3(NT-3)on interdigestive migrating motor complex (MMC) in rats with D-galactosamine induced acute liver injury.</p><p><b>METHODS</b>Twenty-four specific pathogen-free purebred rats were equally randomized into control and acute liver injury groups. The control group was injected with equal volume of normal saline via tail vein. Acute liver injury model of the rats was induced by D-galactosamine injection via the tail vein in the acute liver injury group. And the indexes of interdigestive MMC before and after NT-3 injection were recorded by a polygraph and analyzed in model group. The serum NT-3 concentration was assayed in the two groups.</p><p><b>RESULTS</b>There were no significant changes of gastrointestinal MMC cycle and jejunal phase I MMC after NT-3 injection. Compared with the acute liver injury rats before NT-3 injection , the antral phases I, III and IV MMC were significantly prolonged [(577.44 ± 248.60)s vs (343.58 ± 227.30) s, (80.94 ± 21.15) s vs (24.76 ± 7.41) s, (405.69 ± 131.34) s vs (191.67 ± 128.15) s, P < 0.05] and the phase II MMC was shortened [ (883.94 ± 488.50) s vs (1519.00 ± 831.14) s, P < 0.05] in the acute liver injury group. The duodenal phases I, III and IV MMC were significantly prolonged [ (557.63 ± 335.14) s vs (309.46 ± 220.22) s,(75.91 ± 15.75) s vs (31.15 ± 13.67) s, (423.38 ± 135.22) s vs (209.77 ± 123.83) s, P < 0.05] and MMC II phase was shortened [ (748.81 ± 579.69) s vs (1535.86 ± 930.50) s, P < 0.05] in the acute liver injury rats. In addition, the jejunal MMC III and MMC IV phase was significantly prolonged [ (86.58 ± 23.40) s vs (31.41 ± 16.09) s,(385.18 ± 110.02) s vs (220.59 ± 159.30) s, P < 0.05] and phase II MMC was shortened [ (876.89 ± 652.01) s vs (1870.89 ± 1010.35) s, P < 0.05 ] in the acute liver injury rats. The serum NT-3 level was significantly higher in model group than in control group.</p><p><b>CONCLUSION</b>NT-3 could enhance the gastrointestinal motility in acute liver injury rats.</p>

The changes of interdigestive migrating motor complex in rats with acute liver failure / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To observe the changes and characteristics of interdigestive migrating motor complex (MMC) in rat models of acute liver failure.</p><p><b>METHODS</b>30 rat models with acute liver failure were induced with D-galactosamine and another 30 normal rats were used as controls. The indexes of MMC recorded by multi-channel physiological recorder were compared.</p><p><b>RESULTS</b>No significant differences found between the two groups in antral and duodenal MMC cycles and frequencies of duodenal and jejunal MMC III phase. Compared with normal controls, the MMC II phase in the acute liver failure rats was significantly prolonged (t=-3.97, -3.85, P<0.05), the MMC III duration of antrum and duodenum (u=-4.99, t=4.66, P<0.05) was shorter and the MMC III frequency of antrum (u=-4.73, P<0.05) was faster. In addition, the MMC cycle and MMC III phase of jejunum were significantly prolonged (u=-1.63, t=-4.94, P<0.05) and the MMC III phase duration was significantly shorter in the acute liver failure rats (t=5.10, P<0.05).</p><p><b>CONCLUSION</b>Significantly prolonged MMC II phase characterized by migrating clustered contraction, shortened MMC III phase and extended jejunal MMC cycles were probably the major contributors to the gastrointestinal motility disorders in the rats with acute liver failure.</p>

A retrospective study of clinical and pathological spectrum in 91 patients with chronic severe hepatitis B / 中华肝脏病杂志

<p><b>OBJECTIVE</b>In China, liver failure is also termed as severe hepatitis in whom chronic severe hepatitis B (CSHB) is most common. The aim of this study was to assess whether CSHB based on different liver injury extent can meet the international definition of acute-on-chronic liver failure(ACLF)criteria, according by their clinical and pathological feature.</p><p><b>METHODS</b>A total of 91 patients with CSHB were involved in the study. The clinical findings, laboratory data and liver pathology features were retrospectively analyzed and grouped by hepatitis virus B carrier state (HBC), chronic hepatitis B (CHB) or liver cirrhosis (LC) before they started liver failure.</p><p><b>RESULTS</b>74 out of the 91 patients were male and 17 were female, the mean age was 40.6+/-11.2 years. 9.9%, 7.7% and 82.4% of the patients were based on HBC, CHB and LC respectively. The ages of HBC group were youngest. The mean age of HBC group (years) (25.8+/-6.6) was significantly lower than that of CHB group (36.9+/-9.0) and LC group (42.0+/-10.5)with P values of 0.032 and 0.001 respectively. Most cases presented with sub-acute liver failure characterized by high icterus and ascites. Predisposing factors included exertion, superinfection, virus variation, drugs or alcoholic injury. No difference found between PTA (F = 0.906, P = 0.408) and TBil (F = 0.839, P = 0.436) among the above three groups. The Alb and CHE levels in LC group were (30.3+/-5.1) g/L and (2926.8+/-1471.1) U/L respectively, which were lower than both HBC group [Alb (35.6+/-5.1) g/L, CHE (4363.5+/-2063.2) U/L] and CHB group [Alb (37.4+/-5.0) g/L, CHE (5167.1+/-1522.1) U/L] (F = 9.450; F = 9.297; P value less than 0.01).The level of CHO (1.8+/-1.0) mmol/L in LC group was lower than that of HBC group (2.9+/-1.0mmol/L, P = 0.034), while serum HBV DNA level of HBC group [(6.8+/-1.7) log10copies/ml] was higher than that of LC group [(4.2+/-2.6) log10copies/ml]. The liver tissue in HBC and CHB group showed massive or submassive necrosis which distribute evenly in different parts of liver and similarly in slides, most like acute/subacute severe hepatitis. The chronic lesion was easily covered by extensive necrosis in CSHB based on CHB, with portal fibrosis can be seen by masson stain. Characteristic picture of LC group were massive or submassive necrosis with some nodules were intact or only patchy necrosis of the parenchyma, disparity of extent and stage of necrosis existed in slides, which were the major difference in histopathological change in HBC and CHB group.</p><p><b>CONCLUSION</b>Most of CSHB cases were based on liver cirrhosis, which match with the international definition of ACLF, while small part of CSHB cases based on HBC and CHB are identical to acute/subacute liver failure.</p>

Histopathological changes in livers of patients with chronic severe hepatitis B / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To investigate the histopathological features in livers of chronic severe hepatitis B (CSHB) patients.</p><p><b>METHODS</b>Histology of 42 livers was studied. HE, Masson, Sweet and D-PAS staining and cytokeratin 7, CD68 and proliferating cell nuclear antigen immuno-histochemical staining were used in the study.</p><p><b>RESULTS</b>In CSHB, the livers showed massive or submassive necrosis in a background of other histological changes of chronic hepatitis B. The characteristic pictures of these livers were necrosis of all the hepatocytes in some nodules, while in other nodules there were only patchy necroses of the parenchyma. In some other nodules the necrotic hepatocytes were all removed and only the scaffolding stroma remained. Meanwhile, regeneration of hepatocytes and bile ductules were also seen.</p><p><b>CONCLUSIONS</b>The liver histopathological changes in CSHB are identical, but not of the same degree as those of acute severe and subacute severe hepatitis B. In making differential diagnoses for liver aspiration biopsies of these patients, this fact should be kept in mind.</p>

Establishment of a D-galactosamine/lipopolysaccharide induced acute-on-chronic liver failure model in rats / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To establish a practical and reproducible animal model of human acute-on-chronic liver failure for further study of the pathophysiological mechanism of acute-on-chronic liver failure and for drug screening and evaluation in its treatment.</p><p><b>METHODS</b>Immunological hepatic fibrosis was induced by human serum albumin in Wistar rats. In rats with early-stage cirrhosis (fibrosis stage IV), D-galactosamine and lipopolysaccharide were administered. Mortality and survival time were recorded in 20 rats. Ten rats were sacrificed at 4, 8, and 12 hours. Liver function tests and plasma cytokine levels were measured after D-galactosamine/lipopolysaccharide administration and liver pathology was studied. Cell apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay.</p><p><b>RESULTS</b>Most of the rats treated with human albumin developed cirrhosis and fibrosis, and 90% of them died from acute liver failure after administration of D-galactosamine/lipopolysaccharide, with a mean survival time of (16.1+/-3.7) hours. Liver histopathology showed massive or submassive necrosis of the regenerated nodules, while fibrosis septa were intact. Liver function tests were compatible with massive necrosis of hepatocytes. Plasma level of TNFalpha increased significantly, parallel with the degree of the hepatocytes apoptosis. Plasma IL-10 levels increased similarly as seen in patients with acute-on-chronic liver failure.</p><p><b>CONCLUSION</b>We established an animal model of acute-on-chronic liver failure by treating rats with human serum albumin and later with D-galactosamine and lipopolysaccharide. TNFalpha-mediated liver cell apoptoses plays a very important role in the pathogenesis of acute liver failure.</p>

Analysis on the multi-distribution and the major influencing factors on severe acute respiratory syndrome in Beijing / 中华流行病学杂志

<p><b>OBJECTIVE</b>To analyse the multi-dimension nature of severe acute respiratory syndrome (SARS) transmission.</p><p><b>METHODS</b>Based on the data of SARS in 2003 and the geographic information system of Beijing, as well as under the broad range of the theorems and techniques of data-driven and model-driven knowledge mining, hierarchical techniques were used to test the hot spots. Wavelet technique was also used to decompose Moran's I frequency to survey the spatial clustering process of SARS. For factors analysis, BW test was used to distinguish factors which influencing SARS process. In temporal aspects, susceptive-infective-removal model (SIR) without Taylor expansion was solved by a genetic-simulated annealing algorithm, that directly provided a new approach to obtain epidemic parameters from the SIR model.</p><p><b>RESULTS</b>Different order of spatial hot spots were noticed and the clustering were relevant with the means of transportation. Diffusion dynamics were changed along with the temporal process of SARS. Regarding factor analysis, geographic relationship, population density, the amount of doctors and hospitals appeared to be the key elements influencing the transmission of SARS. The predictable number of SARS cases evolving with time were also calculated.</p><p><b>CONCLUSIONS</b>Cluster detection of close contacts of SARS infective in Beijing revealed the spatial characters of urban population flow and having important implications in the prevention and control of this communicable diseases. Some human and physical environment factors played statistical significant roles in different periods during SARS epidemics. An efficient algorithm was developed to solve SIR model directly, enabling the estimation of epidemic parameters from SIR and early forecast.</p>