Protective effect of resveratrol on lens epithelial cell apoptosis in diabetic cataract rat

Objective: To study the protective effect of resveratrol on lens epithelial cell apoptosis in diabetic cataract rat. Methods: A total of 84 Wistar rats were divided into 4 groups: 12 in Group A (control group), 24 in Group B (diabetic cataract group), 24 in Group C (therapeutic-dose of resveratrol group) and 24 in Group D (low-dose of resveratrol group). Rats in Group B-D were given with 60 mg/kg streptozotocin through intraperitoneal injection. Rats in Group C were given with 100 mg/kg resveratrol and rats in Group D were given with 20 mg/kg resveratrol. The caspase-3 expression levels and apoptosis ratios of LEC among each group were observed; the degrees of lens opacity in Group B-D after 12 weeks were compared. Results: There were significant differences in caspase-3 expression levels, apoptosis ratios of LEC among groups at 4 w, 8 w and 12 w (. P<0.05). After 12 weeks, in Group B the degree of lens opacity was as follow: 0 (0.00%) in grade I, 3 (37.50%) in grade II, 2 (25.00%)in grade III, 2 (25.00%)grade IV, and 1 (12.50%) in grade V; in Group C: 2 (25.00%)in grade I, 4 (50.00%) in grade II, 2 (25.00%)in grade III, 0 (0.00%)grade IV, and 0 (0.00 %) in grade V; in Group D: 1 (12.50%)in grade I, 4 (50.00%) in grade II, 2 (25.00%) in grade III, 1 (12.50%) grade IV, and 0 (0.00%) in grade V. The difference among Group B-D was statistically significant (. P<0.05). Conclusions: Resveratrol has protective effect on lens epithelial cell apoptosis in diabetic cataract rat, and the effect is relative to its dose.

Protective effect of resveratrol on lens epithelial cell apoptosis in diabetic cataract rat

OBJECTIVE@#To study the protective effect of resveratrol on lens epithelial cell apoptosis in diabetic cataract rat.@*METHODS@#A total of 84 Wistar rats were divided into 4 groups: 12 in Group A (control group), 24 in Group B (diabetic cataract group), 24 in Group C (therapeutic-dose of resveratrol group) and 24 in Group D (low-dose of resveratrol group). Rats in Group B-D were given with 60 mg/kg streptozotocin through intraperitoneal injection. Rats in Group C were given with 100 mg/kg resveratrol and rats in Group D were given with 20 mg/kg resveratrol. The caspase-3 expression levels and apoptosis ratios of LEC among each group were observed; the degrees of lens opacity in Group B-D after 12 weeks were compared.@*RESULTS@#There were significant differences in caspase-3 expression levels, apoptosis ratios of LEC among groups at 4 w, 8 w and 12 w (P<0.05). After 12 weeks, in Group B the degree of lens opacity was as follow: 0 (0.00%) in grade I, 3 (37.50%) in grade II, 2 (25.00%)in grade III, 2 (25.00%)grade IV, and 1 (12.50%) in grade V; in Group C: 2 (25.00%)in grade I, 4 (50.00%) in grade II, 2 (25.00%)in grade III, 0 (0.00%)grade IV, and 0 (0.00 %) in grade V; in Group D: 1 (12.50%)in grade I, 4 (50.00%) in grade II, 2 (25.00%) in grade III, 1 (12.50%) grade IV, and 0 (0.00%) in grade V. The difference among Group B-D was statistically significant (P<0.05).@*CONCLUSIONS@#Resveratrol has protective effect on lens epithelial cell apoptosis in diabetic cataract rat, and the effect is relative to its dose.

Relationship between ambient fine particles and ventricular repolarization changes and heart rate variability of elderly people with heart disease in Beijing, China / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To explore the effects of particulate matters less than 2.5 μm in aerodynamic diameter (PM2.5) on heart repolarization/depolarization and heart rate variability (HRV).</p><p><b>METHODS</b>We conducted a panel study for elderly subjects with heart disease in Beijing from 2007 to 2008. PM2.5 was measured at a fixed station for 20 h continuously each day while electrocardiogram (ECG) indexes of 42 subjects were also recorded repeatedly. Meteorological data was obtained from the China Meteorological Data Sharing Service System. A mixed linear regression model was used to estimate the associations between PM2.5 and the ECG indexes. The model was adjusted for age, body mass index, sex, day of the week and meteorology.</p><p><b>RESULTS</b>Significant adverse effects of PM2.5 on ECG indexes reflecting HRV were observed statistically and the strongest effect of PM2.5 on HRV was on lag 1 day in our study. However, there were no associations between PM2.5 and ECG indexes reflecting heart repolarization/depolarization. Additionally, the effects of PM2.5 on subjects with hypertension were larger than on the subjects without hypertension.</p><p><b>CONCLUSION</b>This study showed ambient PM2.5 could affect cardiac autonomic function of the elderly people with heart disease, and subjects with hypertension appeared to be more susceptive to the autonomic dysfunction induced by PM2.5.</p>

Chlormequat residues and dissipation rates in cotton crops and soil.

A simple and reliable analytical method for chlormequat residues in cotton and soil was established in this study. The residual levels and dissipation rates of chlormequat in cotton crops and soil were determined by High Performance Liquid Chromatography-Mass Spectroscopy (HPLC-MS). The limit of quantification (LOQ) was 0.05, 0.1, 0.1mg/kg for soil, cotton seeds and cotton leaves, respectively. The mean half-life of chlormequat was 4.47 days in cotton plants and was 4.34 days in soil. The final residues of chlormequat in cotton seeds were below 0.5mg/kg (the MRL of China), while the chlormequat residues could not be detected in soil. Low residues in cotton seed and soil suggest that this pesticide may be safe to use under the recommended dosage.

Dissipation and residues of chlormequat in wheat and soil.

A specific, sensitive method was developed for the analysis of chlormequat in wheat and soil by high performance chromatography/mass spectrometry. The fortified recoveries of soil were from 75.08% to 96.55%, with RSD 3.34%-15.18%, the limit of detection of the analytical method was 0.05 ng at a signal-to-noise ratio of 3, and the limit of quantification was 0.05, 0.1, 0.5 mg/kg for soil, wheat plants and wheat grain, respectively. The degradation dynamics and final residues of chlormequat in Beijing and Changchun were investigated. The half-life of chlormequat in wheat plants were 3.15 days in Beijing and 4.56 days in Changchun, while the half-life in soil was 3.88 days in Beijing and 4.51 days in Changchun. The final residues of chlormequat in soil were not detectable, and the final residues of chlormequat in wheat grain were below 0.50 mg/kg except for 3.51 mg/kg from high dosage plot of Changchun. The fact that all the final residues were below 5 mg/kg (GB2763 in National standards of the People's Republic of China, maximum residue limits for pesticide in food, Beijing, 2005) suggested that chlormequat could be safely used in wheat crops with the suitable dosage and application.

Association between ambient temperature and hospital emergency room visits for cardiovascular diseases:a case-crossover study / 中华流行病学杂志

Objective To explore the association between ambient average temperature and hospital emergency room visits for cardiovascular diseases(International Classification of Diseases,Tenth Vision ICD-10:I00-I99) in Beijing,China.Methods Data was collected on daily hospital emergency room visits for cardiovascular diseases from Peking University Third Hospital,including meteorological data(daily average temperature,relative humidity,wind speed,and atmospheric pressure) from the China Meteorological Data Sharing Service System,and on air pollution from the Beijing Municipal Environmental Monitoring Center.Time-stratified case-crossover design was used to analyze data on 4 seasolls.Results After adjusting data on air pollution,1 degree(℃) increase of ambient average temperature would associate with the emergency room visits of odds ratio(Ors)as 1.282(95%CI:1.250-1.315).1.027(95%CI:1.001-1.055),0.661(95%CI:0.637-0.687),and 0.960 (95%CI:0.937-0.984) in spring,summer,autumn,and winter respectively.After controlling the influence of relative humidity,wind speed,and atmospheric pressure,1℃ increase in the ambient average temperature would be associated with the emergency room visits on Ors value as 1.423 (95%CI:1.377-1.471).1.082(95%CI:1.041-1.124),0.633(95%CI:0.607-0.660)and 0.971(95%CI:0.944-1.000) in spring,summer,auttmm,and winter respectively.Conclusion These data on outcomes suggested that the elevated level of ambient temperature would increase the hospital emergeney room visits for cardiovascular diseases in spring and summer while the elevated level of ambient temperature would decrease the hospital emergency room visits for the cardiovascular diseases in autumn and winter,suggesting that patients with cardiovascular diseases should pay attention to the climate change.

Effects of MRP2-GSH cotransport system on hepatic arsenic metabolism in rats / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the role of multidrug resistant protein 2 (MRP2) and glutathione (GSH) cotransport system in hepatic arsenic metabolism in rats.</p><p><b>METHODS</b>Thirty healthy Wistar rats were divided randomizedly into five groups. The first group was the control group and the rats in this group were administered with normal saline. In the second, third and fourth group the rats were administered with 4, 10 and 20 mg As(+)3/kg BW of sodium arsenite respectively every other day for two weeks. The fifth group was the benzene-soluble organics (BSO) intervention group and in this group the rats were administered with 2 mmol/kg BW BSO intraperitoneally every day three days before the end of the experiment. The other treatment was the same as in other groups. All rats were sacrificed two weeks after the treatments. Arsenic contents in bile, liver and blood were detected by atomic absorption spectroscopy (AAS), and the expression of MRP2 in the membrane of hepatocyte was determined by Western-blot analysis.</p><p><b>RESULTS</b>The level of total arsenic (including organic arsenic and inorganic arsenic) in bile, liver and blood in all three different dose groups was higher than those in the control groups (P < 0.05). Arsenic levels of bile and liver were increased with intragastric arsenic dose. Blood arsenic levels were not significantly different in three different dose groups. Expression of hepatic MRP2 was increased with intragastric arsenic concentration. A positive correlation between biliary arsenic concentration and MRP2 levels was found in liver (r = 0.986, P < 0.05). For the rats pretreated with BSO, the biliary arsenic was significantly higher than that in the control group but lower than that in the high dose group; the liver and blood arsenic was higher than that in the control group and in the high dose group. Expression of MRP2 pretreated with BSO was decreased.</p><p><b>CONCLUSION</b>Sodium arsenite can induce expression of MRP2 and the up-regulation of MRP2 may play an important role in the bile secretion of arsenite and its metabolites. The function of MRP2 for transportation of arsenic and its metabolites is associated with the intracellular GSH level. BSO inhibits the synthesis of GSH, which weakens the function of the MRP2-GSH cotransport system and makes the liver arsenic increased.</p>

Toxic effect of arsenite on the expression of liver multidrug resistance-associated protein 2 in rat / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the role of multidrug resistance-associated protein 2 (MRP2) in the hepatic cell membrane of rats.</p><p><b>METHODS</b>Thirty healthy Wistar rats were divided randomly into six groups based on time of administration (2 w, 4 w, 6 w) of 20 mg/kg of sodium arsenite, and their corresponding control groups. Animals were administered every other day. Arsenic content in blood and bile were detected by atomic absorption spectroscopy (AAS), and the expression of MRP2 in the membrane of hepatocyte by Western blotting was determined.</p><p><b>RESULTS</b>Total arsenic levels (including organic arsenic and inorganic arsenic) in blood and bile were significantly higher than control groups (P < 0.05) at all three different time points, especially in 2 w and 4 w group (16.8 and 13.8 fold greater than that in control). The expression of MRP2 increased 36.61%, 32.36%, 12.73% more respectively in 2 w, 4 w, 6 w groups than those in control groups (P < 0.05). The expression of MRP2 was correlated with total arsenic content in bile (r = 0.713, P < 0.05).</p><p><b>CONCLUSIONS</b>Bile is one of the major routes for the excretion of arsenite and its metabolites, and the overexpression of MRP2 may play an important role in the bile excretion of them at early stage.</p>