Expression of Hsp27 and Hsp70 in Lymphocytes and Plasma in Healthy Workers and Coal Miners with Lung Cancer

In coal mines, main occupational hazard is coal-mine dust, which can cause health problem including coal workers’ pneumoconiosis and lung cancer. Some heat shock proteins (Hsps) have been reported as an acute response to a wide variety of stressful stimuli. Whether Hsps protect against chronic environmental coal-mine dust over years is unknown. It is also interesting to know that whether the expression of Hsp27 and Hsp70 proteins as a marker for exposure is associated risk of lung cancer among coal miners. We investigated the association between levels of Hsp27 and Hsp70 expression in lymphocytes and plasma and levels of coal-mine dust exposure in workplace or risk of lung cancer in 42 cancer-free non-coal miners, 99 cancer-free coal miners and 51 coal miners with lung cancer in Taiyuan city in China. The results showed that plasma Hsp27 levels were increased in coal miners compared to non-coal miners (P<0.01). Except high cumulative coal-mine dust exposure (OR=13.62, 95%CI=6.05—30.69) and amount of smoking higher than 24 pack-year (OR=2.72, 95% CI=1.37—5.42), the elevated levels of plasma Hsp70 (OR=13.00, 95% CI=5.14—32.91) and plasma Hsp27 (OR=2.97, 95% CI=1.40—6.32) and decreased expression of Hsp70 in lymphocytes (OR=2.36, 95% CI=1.05—5.31) were associated with increased risk of lung cancer. These findings suggest that plasma Hsp27 may be a potential marker for coal-mine dust exposure. And the expression of Hsp27 and Hsp70 levels in plasma and lymphocytes may be used as biomarkers for lung cancer induced by occupational coal-mine dust exposure.

A Pilot School Meal Program Using Local Foods with Soybean in Rural Bangladesh: Effects on the Nutritional Status of Children

Background: Growth retardation is a challenge in Bangladesh. School feeding programs with fortified biscuits have been evaluated in Bangladesh. However, the impacts of a school meal program using local foods on the growth and nutritional status of children have not been investigated. Objective: To determine whether a school meal program (SMP) using local foods with soybean could improve children’s growth and micronutrient status in rural Bangladesh. Methods: Two primary schools were randomly assigned as intervention (SMP;n = 200) and control (non-SMP;n = 200) schools. Children in the intervention school were supplied a school meal with local foods including soybean, containing more than one-third of the recommended daily allowance of energy and nutrients, 5 days/week for 8 months. The attendance rate and school lunch consumption of the children were monitored. Baseline and final anthropometry, hemoglobin and micronutrient status were assessed. Results: There were no significant differences in anthropometric measurements at baseline between the intervention and control groups, but there were differences in the prevalence of anemia, vitamin A deficiency and zinc deficiency. After the intervention, children in the SMP school showed a larger degree of improvement in the height-for-age Z-score (P Conclusion: A school meal program using local foods with soybean improved the height velocity and hemoglobin concentration of children in rural Bangladesh.

Spectrophotometric Determination of Silicon Tetrahydride in the Air of Workplace

A new, simple and sensitive method was developed for the determination of silicon tetrahydride in the air of workplace in this study. The alkaline resin-based spherical activated carbon was used to collect sample of silicon tetrahydride at workplace. Silicon tetrahydride was then desorbed from active carbon in 100°C hot water. After reacting with ammonium molybdate, oxalic acid and 1,2,4-trichlorobenzene alpha-naphthol amino sulfonic acid under acid condition, silicon tetrahydride was transformed into silicon molybdenum blue. The absorbance of silicon molybdenum blue was quantitatively measured at the wavelength of 680 nm. The results showed that the average sampling efficiency and desorption efficiency were 97.53% and 94.94%, respectively by this method. Detection limits were 0.054 μg/m L for the spectrophotometric method and 0.14 mg/m3 for the determination of silicon tetrahydride in the air of workplace（sampling volume was 7.5 L）. The conversion rate of silicon tetrahydride gradually decreased when storage time of samples was extended. The descent rate of sample was less than 10% when the sample was sealed for 7 days in the room temperature. It was concluded that this spectrophotometric method can be successfully used to determine silicon tetrahydride in the worksites.

Cohort Mortality Study in Three Ceramic Factories in Jingdezhen in China

To investigate the health impacts of crystalline silica mixed dust and other potential occupational hazards on workers in ceramic factories, a cohort study of 4851 workers registered in the employment records in 3 ceramic factories in Jingdezhen city of China between 1972 and 1974 was identified. The cohort mortality was traced throughout 2003 with an accumulation of 128970.2 person-years, revealed 1542 deaths. Standardized mortality ratios （SMRs） were calculated for the main causes of death by using Chinese national mortality rates as reference. The mortality from all causes in three ceramic factories was 12.0‰ and the cumulative mortality was 31.8%. Malignant neoplasm, cardiovascular diseases, respiratory diseases, infectious diseases were the first four illnesses that threaten workers’ life, and they accounted for 73.2% of all deaths. The results of this study showed that the standardized mortality ratio for all subjects was 1.02, which is very close to that expected on the basis of the China national mortality rates. Statistically significant mortality excesses for respiratory disease （SMR=1.36）, pneumoconiosis （SMR=37.34）, infectious disease （SMR=5.70） and pul- monary tuberculosis （SMR=3.88） were observed. The mortality of 2938 dust-exposed workers was higher than that of 1913 non dust-exposed workers. Except for pneumoconiosis, the mortality from lung cancer, non-malignant respiratory diseases and pulmonary tuberculosis in dust-exposed workers were significantly increased as compared with that in non-exposed workers, and the relative risks （RRs） were 1.86 （1.16–2.99）, 2.50 （1.84–3.40）, 1.81 （1.34–2.45）. The exposure-response relationships between cumulative dust exposure level and mortality from all causes, colorectal cancer, lung cancer, respiratory diseases, and pulmonary tuberculosis were also identified. The findings indicated that silica mixed dust in ceramic factories has harmful impact on the workers’ health and life span in ceramic factory.

Effects of backrest density on lumbar load and comfort during seated work

Background Seated workplaces have greatly increased in China. Many researchers have found that seated work is a risk factor in the development of low-back pain. Backrest can reduce the load on the lower back by transmitting more of the weight from the upper body to the floor via the backrest so as to prevent low-back pain. To design a suitable chair backrest for seated office work, some backrest parameters must be optimized. In this study, the role of backrest density on lumbar load and comfort were investigated. The goal of the study was to help establish criteria with which backrests that alleviate and prevent low back pain during seated office work can be designed and selected. Methods Twenty volunteers （10 men and 10 women） were seated in three backrest conditions （10 kg/m^3, 25 kg/m^3, and 40 kg/m^3）. Pressure data, including contact pressure （CP）, peak contact pressure （PCP） and contact area were collected during 15-minute trial. Subjective data were collected after each pressure test. Results Backrest density had a significant effect on backrest pressure variables. CP and PCP increased with increasing backrest density. Contact area decreased with increased density. In terms of user preference, the backrest with low density was most highly rated. Conclusions Backrest density plays an important role in lumbar load and comfort during seated work. During designing and selecting backrests, backrest density should be focused on so as to alleviate and prevent low-back pain during seated office work. Backrest density at 10 kg/m^3 got the lowest CP and PCP and largest contact area. Backrest with low density can reduce lumbar pressure and increase support contact area, which could raise comfort feeling. Backrest density at 10 kg/m^3 is better to maintain a balance between providing effective support and alleviating excess lordosis.

Human bronchial epithelial cell injuries induced by fine particulate matter from sandstorm and non-sandstorm periods：Association with particle constituents

Epidemiological studies have demonstrated the exacerbation of respiratory diseases following sandstorm-derived particulate matter（PM） exposure.The presence of anthropogenic and biological agents on the sandstorm PM and the escalation of PM 〈 2.5 μm（PM2.5）pollution in China have led to serious concerns regarding the health effects of PM2.5during Asian sandstorms.We investigated how changes in PM2.5composition,as the weather transitioned towards a sandstorm,affected human airway epithelial cells.Six PM2.5samples covering two sandstorm events and their respective background and transition periods were collected in Baotou,an industrial city near the Gobi Desert in China.PM samples from all three periods had mild cytotoxicity in human bronchial epithelial cell line BEAS-2B,which was positively correlated with the contents of polycyclic aromatic hydrocarbons and several metals.All PM samples potently increased the release of interleukin-6（IL-6） and interleukin-8（IL-8）.Endotoxin in all samples contributed significantly to the IL-6 response,with only a minor effect on IL-8.Cr was positively correlated with both IL-6 and IL-8 release,while Si was only associated with the increase of IL-6.Our study suggests that local agricultural and industrial surroundings in addition to the sandstorm play important roles in the respiratory effects of sandstorm-derived PM.