Humans ; Occupational Health Physicians ; organization & administration ; Personnel Selection

Dermatitis, Occupational ; etiology ; Humans ; Trichloroethylene

China ; Occupational Health Services ; Pilot Projects

OBJECTIVETo study the hazards of gem dusts and the epidemiological features of the occurrence of gem worker's silicosis (GWS).

METHODSEpidemiological investigation in a gem factory in Guangdong province was carried out.

RESULTSThe average dusts concentration in workshop was 2.3 mg/m(3), average free silica content was 94.64%. There were 47 patients diagnosed as silicosis. The prevalence of GWS was 4.58% (47/ 1,027). The age of patients suffering from silicosis and the duration of dust exposure were (27.04 +/- 3.25) years and (4.67 +/- 1.17) years respectively. Chest radiographic examination showed mainly small round opacities "q". The incidences of GWS complicated by pulmonary tuberculosis, spontaneous pneumothorax and pulmonary emphysema were 10.64%, 10.64%, 44.68% respectively.

CONCLUSIONThe hazards of gem dust to workers might be serious. Higher incidence, younger age suffered from silicosis, shorter duration of dust exposure, more complications, and poorer prognosis in gem workers appeared to be the main epidemiological features of GWS in Guangdong.

Adult ; Air Pollutants, Occupational ; poisoning ; China ; epidemiology ; Female ; Humans ; Male ; Occupational Diseases ; epidemiology ; etiology ; Silicosis ; epidemiology ; etiology

OBJECTIVETo investigate the incidence of welder's pneumoconiosis in container manufacturing industries in Guangdong province and present some preventive and curative strategy.

METHODSOccupational epidemiology study methods were used to study the incidence of welder's pneumoconiosis in two container manufacturing enterprises (enterprise A and enterprise B).

RESULTSBefore 2004, the rate of up-to-standard of weld fume concentration in the workplaces was relatively low (< or = 40%), and the maximum value of time weighted average (TWA) was 26.7 mg/m(3). After 2004, with the system of dust control, the rate of up-to-standard was 85% in the enterprise A. Of the 813 weld workers examined, 19 were diagnosed as welder's pneumoconiosis (stage I was 15, while I (+) was 4 ) and the incidence was 2.34% (19/813). The age of electric welders suffering from welder's pneumoconiosis and the duration of dust exposure were (33.45 + 4.64) and (8.04 + 1.97) years respectively. Chest radiographic examination showed mainly small round opacities "p". The value of MVV, FEF25%, FEF50% and FEF75% in lung function tests were significantly lower than those of the control group (P < 0.05 or P < 0.01).

CONCLUSIONThe main features of welder's pneumoconiosis in container manufacturing industries are the short duration of dust exposure, and small round opacities "p" in the chest radiographs. Therefore, it should be the key point of the prevention and treatment of occupational diseases in this industry to control the harmful weld fume.

Adult ; China ; epidemiology ; Dust ; Female ; Humans ; Male ; Occupational Exposure ; adverse effects ; Pneumoconiosis ; epidemiology ; Welding

Adolescent ; Adult ; Female ; Humans ; Male ; Mercury ; urine ; Middle Aged ; Reference Values ; Spectrophotometry, Atomic

OBJECTIVE: To investigate the effect of the power-frequency electromagnetic field on antioxidant indexes in operation personnel. METHODS: By random sampling method,a total of 58 workers who work in 500 kV transformer substations for at least 5. 0 years were selected as the exposure group,and 60 administrative staffs in the same enterprise were included as the control group. The power frequency electromagnetic fields in the 2 groups were measured. The cumulative exposure dose of individual magnetic field was calculated. Peripheral venous blood was collected in these 2groups and was examined with the superoxide dismutase( SOD) activity,malondialdehyde( MDA) level and the relative gene expression level of manganese superoxide dismutase( MnSOD). RESULTS: There was no statistical significance in the SOD activity,MDA level and the relative gene expression level of MnSOD between the exposure group and the control group( P > 0. 05). The logistic regression analysis results indicated that cumulative exposure dose was not correlated with the SOD activity,MDA level and the relative gene expression level of MnSOD after adjusting confounding factors such as age,smoking,alcohol and tea drinking( P > 0. 05). CONCLUSION: Power-frequency electromagnetic field exposure has no significant effects on the SOD activity,MDA level and the relative gene expression level of MnSOD of operation workers.

This study investigated the effect and mechanism of morin in inducing autophagy and apoptosis in hepatocellular carcinoma cells through the protein kinase B(Akt)/mammalian target of rapamycin(mTOR)/signal transducer and activator of transcription protein 3(STAT3) pathway. Human hepatocellular carcinoma SK-HEP-1 cells were stimulated with different concentrations of morin(0, 50, 100, 125, 200, and 250 μmol·L~(-1)). The effect of morin on the viability of SK-HEP-1 cells was detected by Cell Counting Kit-8(CCK-8). The effect of morin on the proliferation and apoptosis of SK-HEP-1 cells was investigated using colony formation assay, flow cytometry, and BeyoClick~(TM) EdU-488 with different concentrations of morin(0, 125, and 250 μmol·L~(-1)). The changes in the autophagy level of cells treated with morin were examined by transmission electron microscopy and autophagy inhibitors. The impact of morin on the expression levels of proteins related to the Akt/mTOR/STAT3 pathway was verified by Western blot. Compared with the control group, the morin groups showed decreased viability of SK-HEP-1 cells in a time-and concentration-dependent manner, increased number of apoptotic cells, up-regulated expression level of apoptosis marker PARP, up-regulated phosphorylation level of apoptosis-regulating protein H2AX, decreased number of positive cells and the colony formation rate, an upward trend of expression levels of autophagy-related proteins LC3-Ⅱ, Atg5, and Atg7, and decreased phosphorylation levels of Akt, mTOR, and STAT3. These results suggest that morin can promote apoptosis, inhibit proliferation, and induce autophagy in hepatocellular carcinoma cells, and its mechanism of action may be related to the Akt/mTOR/STAT3 pathway.
Humans ; Proto-Oncogene Proteins c-akt/metabolism* ; Carcinoma, Hepatocellular/pathology* ; Liver Neoplasms/pathology* ; TOR Serine-Threonine Kinases/metabolism* ; Apoptosis ; Autophagy ; Cell Proliferation ; Cell Line, Tumor ; STAT3 Transcription Factor/metabolism*

This study aimed to investigate the effect and molecular mechanism of sinomenine on proliferation, apoptosis, metastasis, and combination with inhibitors in human hepatocellular carcinoma HepG2 cells and SK-HEP-1 cells. The effect of sinomenine on the growth ability of HepG2 and SK-HEP-1 cells were investigated by CCK-8 assay, colony formation assay, and BeyoClick~(TM) EdU-488 staining. The effect of sinomenine on DNA damage was detected by immunofluorescence assay, and the effect of sinomenine on apoptosis of human hepatocellular carcinoma cells was clarified by Hoechst 33258 staining and CellEvent~(TM) Cystein-3/7Green ReadyProbes~(TM) reagent assay. Cell invasion assay and 3D tumor cell spheroid invasion assay were performed to investigate the effect of sinomenine on the invasion ability of human hepatocellular carcinoma cells in vitro. The effect of sinomenine on the regulation of protein expression related to the protein kinase B(Akt)/mammalian target of rapamycin(mTOR)/signal transducer and activator of transcription 3(STAT3) signaling pathway in HepG2 and SK-HEP-1 cells was examined by Western blot. Molecular docking was used to evaluate the strength of affinity of sinomenine to the target cysteinyl aspartate specific proteinase-3(caspase-3) and STAT3, and combined with CCK-8 assay to detect the changes in cell viability after combination with STAT3 inhibitor JSI-124 in combination with CCK-8 assay. The results showed that sinomenine could significantly reduce the cell viability of human hepatocellular carcinoma cells in a concentration-and time-dependent manner, significantly inhibit the clonogenic ability of human hepatocellular carcinoma cells, and weaken the invasive ability of human hepatocellular carcinoma cells in vitro. In addition, sinomenine could up-regulate the cleaved level of poly ADP-ribose polymerase(PARP), a marker of apoptosis, and down-regulate the protein levels of p-Akt, p-mTOR, and p-STAT3 in human hepatocellular carcinoma cells. Molecular docking results showed that sinomenine had good affinity with the targets caspase-3 and STAT3, and the sensitivity of sinomenine to hepatocellular carcinoma cells was diminished after STAT3 was inhibited. Therefore, sinomenine can inhibit the proliferation and invasion of human hepatocellular carcinoma cells and induce apoptosis, and the mechanism may be attributed to the activation of caspase-3 signaling and inhibition of the Akt/mTOR/STAT3 pathway. This study can provide a new reference for the in-depth research and clinical application of sinomenine and is of great significance to further promote the scientific development and utilization of sinomenine.
Humans ; Carcinoma, Hepatocellular/genetics* ; Proto-Oncogene Proteins c-akt/metabolism* ; Caspase 3/metabolism* ; Liver Neoplasms/genetics* ; Molecular Docking Simulation ; Sincalide/pharmacology* ; Cell Line, Tumor ; Cell Proliferation ; Hep G2 Cells ; TOR Serine-Threonine Kinases/metabolism* ; Apoptosis