Objective: To study the effect of bilirubin on the functional changes of sarcoplasmic reticulum (SR) induced by acute exercise. [WT5FZ]Methods:[WT5BZ] 41 Wistar male rats were divided into five groups, control group, exercise group, exercise recovery group, bilirubin treated exercise group and bilirubin treated exercise recovery group. The rats were administered with 1 ?mol/kg body weight of bilirubin or saline once every day for 4 weeks. After swimming with load for 2 h, all of the rats were killed and several indices were determined. [WT5FZ]Results:[WT5BZ] Bilirubin could inhibit the decrease of Ca 2+ content and the increase of Ca 2+ ,Mg 2+ ATPase activity in SR induced by acute exercise, and inhibit the increase of Mg 2+ content in cytoplasm. [WT5FZ]Conclusion:[WT5BZ] Bilirubin may delay the development of fatigue induced by acute exercise through protecting certain functions of SR.

OBJECTIVETo study the relationship between glutathione S-transferase M1 (GSTM1) genotypes and lipid peroxidation of asbestos workers.

METHODS94 asbestos workers and 51 controls were selected as subjects. The general information, occupational history and individual habits were collected by questionnaires in all participants. The venous blood was sampled and the plasma was separated for the detection of malondialdehyde (MDA) level and lymphocytes for DNA isolation and GSTM1 genotyping.

RESULTSMDA level was significantly higher in asbestos workers [(0.283 +/- 0.054) nmol/L] than that in controls [(0.163 +/- 0.053) nmol/L, P < 0.01], however, neither duration of exposure nor accumulated asbestos exposure dose was related to MDA levels; MDA levels in control workers with GSTM1 +/- genotype [(0.190 +/- 0.034) nmol/L] were significantly higher than that in control workers with GSTM1 +/+ genotype [(0.138 +/- 0.055) nmol/L, P < 0.01]. Among asbestos workers, the same trend could be found, but the differences was not significant(P > 0.05). When the workers were stratified by duration of exposure or accumulated asbestos exposure dose, MDA levels in individuals with GSTM1 -/- genotype were also higher than those with GSTM1 +/+ genotype, but the differences were also not significant(P > 0.05).

CONCLUSIONBoth exposure to asbestos and deficiency of GSTM1 genotype were related to lipid peroxidation in workers, but the role of the former may be more important than that of the latter.

Asbestos ; adverse effects ; Genotype ; Glutathione Transferase ; genetics ; Humans ; Lipid Peroxidation ; Malondialdehyde ; analysis ; Occupational Exposure

OBJECTIVETo explore the genotoxicity of bass wood dust.

METHODSMicronucleus frequency in peripheral lymphocytes of workers exposed to bass wood dust in a match factory were examined, solution of bass wood dust emmersion was prepared and the effect on micronucleus frequency in poly-dyeing red blood cell of mice's sternum marrow was also detected. Single cell gel electrophoresis assay was used to detect DNA damage in liver cell, the level of oxygen free radical, lipid peroxidation(MDA) in the liver and the activity of superoxide dismutase(SOD) in red blood cells were also studied.

RESULTSThe positive frequency of micronucleus in bass wood-exposed workers with different length of service (0-, 5-, > or = 10 a) were 50.0%, 51.9%, 50.0% respectively, significantly higher (P < 0.01) than that of the control group(4.5%). A dose-effect relationship could also be found in the mice's micronucleus frequency study(r = 0.78, P < 0.01). The activities of SOD[(10.98 +/- 5.74), (15.70 +/- 7.54), (29.63 +/- 14.97) microgram/g Hb] were significantly lower than that of control group[(35.80 +/- 12.92) microgram/g Hb], and the level of MDA[(4.93 +/- 0.90), (4.61 +/- 1.06), (4.33 +/- 0.69) mmol/g liver] were significantly higher than that of the control group[(2.51 +/- 0.34) mmol/g liver]. Single cell gel electrophoresis study showed DNA strand breaks increased with the dose increase and the level of oxygen free radical also increased with the dose increase.

CONCLUSIONBass wood dust may have certain degree of genotoxicity.

Animals ; DNA Breaks ; Dust ; Humans ; Malondialdehyde ; analysis ; Mice ; Micronuclei, Chromosome-Defective ; Micronucleus Tests ; Occupational Exposure ; adverse effects ; Wood