Detecting chlorpyrifos and its metabolitein plasma by UPLC / 中国职业医学

OBJECTIVE: To establish a simple and sensitive method for simultaneous detection of chlorpyrifos( CPF),and its metabolite 3,5,6-trichloro-2-pyridinol( TCP) in plasma samples by ultra performance liquid chromatography( UPLC).METHODS: The 0. 5 m L of blood sample was extracted by ethyl acetate,then separated by C18 column using acetonitrile /water as a mobile phase and detected by diode-array detector under the ultraviolet spectrum of 298 nm( 0. 0-2. 0 min) and289 nm( 2. 0-5. 0 min) through UPLC. RESULTS: The method showed that a good linear range was 1. 00-50. 00 mg / L of both CPF and TCP,and the correlation coefficients was 0. 999 9. The limit of detection was 0. 30 mg / L and the lower limits of quantitation was 1. 00 mg / L of both CPF and TCP. The recovery rates of CPF and TCP were 87. 20 %-103. 08 %and 86. 20 %-99. 28 %,respectively. The within-run relative standard deviation( RSD) of CPF and TCP was 5. 28 %-6. 17 % and 2. 32 %-4. 43 %,and the between-run RSD was 6. 62 %-7. 53 % and 3. 55 %-5. 24 %. Samples can be kept in4 degrees Celsius refrigerator for 7 days. CONCLUSION:s The proposed method is simple,reliable and sensitive. It can be applied for simultaneous detection of CPF and its metabolite TCP in plasma samples.

Effects of hydrogen sulfide preconditioning on myocardial ischemia reperfusion injury in rats / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the effects of hydrogen sulfide preconditioning on myocardial ischemia reperfusion injury in rats.</p><p><b>METHODS</b>Sprague-Dawley male rats were divided into 4 groups with 10 in each group: in S group rats received sham operation; in IR group rats were given with NS (1.0 ml/kg iv) 24 h before ischemia; in H group rats were treated with NaHS (0.05 mg/kg iv) 24 h before ischemia; and in D group, NaHS-treated rats received 5-hydroxydecanoate (5-HD) 15 min before ischemia. Rats in IR group,H group and D group were subjected to ischemia by occlusion of coronary artery for 30 min followed by 2 h of reperfusion. At the end of the reperfusion,myocardial infarct size was measured. SAM-s was measured by Western blotting. Plasma SOD activity and MDA were determined at the end of reperfusion.</p><p><b>RESULTS</b>The infarct size was significantly lesser in H group (25.40 % ± 3.54%) than that in IR group (38.27% ±5.64%,P<0.05). The SAM-s protein expression in myocardium was significantly lower in H group than that in IR group. The plasma MDA content was significantly lower and SOD activity was higher in H group than those in IR group,but there was no difference between IR group and D group.</p><p><b>CONCLUSION</b>The hydrogen sulfide preconditioning attenuates myocardial IR injury possibly through down-regulating SAM-s expression,reducing the production of oxygen free radicals and enhancing anti-oxidize effect in rats.</p>

Detecting the isoflurane in the air of workplaces with chromatographic method / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To establish a solvent desorption Gas chromatographic method for detecting the isoflurane in air of workplaces.</p><p><b>METHODS</b>This method is based on "Standardization of methods for determination of toxic substances in workplace air".</p><p><b>RESULTS</b>This method presents the linear relation with the minimum detectable limit 1.0 µg/ml and the minimum detectable concentration 0.07 mg/m(3). The precision (RSD) was 0.5% ∼ 5.0%, the mean dsorption efficiencies were 96.7% ∼ 98.9%, the absorption efficiencies were 92.1% ∼ 100%, the breakthrough volume was 3.7 mg isoflurane/100 mg active carbon. Other volatile organic solvents (Sevoflurane, Enflurane and Ethyl Alcohol) did not interfere the detection. The sample could be stored in the active carbon tube at least for 10 days.</p><p><b>CONCLUSION</b>This method is meet the requirement of GBZ/T 210.4-2008 "Guide for establishing occupational health standards-Part4: Determination methods of air chemicals in workplace" and is feasible for determining the isoflurane in the air of workplaces.</p>

Determination of phosphoric acid in the air of workplace by ion chromatography / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To develop a method to determine phosphoric acid in the air of workplace by ion chromatography.</p><p><b>METHODS</b>Phosphoric acid was collected by millipore filter and washed by deionized water then detected by ion chromatography.</p><p><b>RESULTS</b>Linearity range of test was 0 ∼ 20 µg/ml, relative standard deviation (RSD) was 1.95% ∼ 3.31%, the elution efficiency was 103.0% ∼ 109.6%, determination limit was 0.1 µg/ml (when sample size was 20.01) concentration limit was 0.01 mg/m(3) (when the collected air was 75 L).</p><p><b>CONCLUSION</b>This method is convenient for air collection, simple, with high sensitivity and good precision, is a good method for determination of phosphoric acid in the air of workplace.</p>

Simultaneous determination of seven chemicals of halogenated alkanes and aromatic hydrocarbons in the air of workplace by gas chromatography / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To establish a gas chromatographic method for determination of halogenated alkanes and aromatic hydrocarbons including trichloromethane, 1,2-dichloroethane, carbon tetrachloride, benzene, toluene, ethylbenzene and xylene in the air of workplace.</p><p><b>METHODS</b>After the air samples collected with activated carbon tubes and desorbed with CS(2), the target toxicants were separated with FFAP capillary columns and detected with flame ionization detector.</p><p><b>RESULTS</b>The coefficient of correlation was above 0.999 and the lowest detectable concentrations were 0.2 ∼ 3.6 mg/m(3) with the RSD of 1.2% ∼ 4.6%. The desorption efficiencies was 94.9% ∼ 100.7%.</p><p><b>CONCLUSION</b>The method shows lower detection limit, high accuracy and precision. It is feasible for determination of the seven halogenated alkanes and aromatic hydrocarbons in the air of workplace.</p>

Effect of hydrogen sulfide-induced delayed preconditioning on glutathione S-transferase expression during myocardial ischemia-reperfusion in rats / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the effect of hydrogen sulfide-induced delayed preconditioning on glutathione S-transferase (GST) expression during myocardial ischemia-reperfusion in rats.</p><p><b>METHODS</b>Sprague-Dawley male rats were randomly divided into 4 groups (n= 10 in each): Group S (sham operation group), Group IR (ischemia/reperfusion group), Group H (IR+ NaHS 0.05 mg/kg iv, 24 h before ischemia) and Groups D receiving IR+NaHS 24 h before ischemia and 5-hydroxydecanoate (5-HD)15 min before ischemia. Animals in groups IR, H and D were subjected to ischemia by 30 min of coronary artery occlusion followed by 2 h of reperfusion. At the end of the reperfusion, myocardial infarct size (IS) was examined. Glutathione S-transferase (GST) was measured by Western blotting. The myocardial ultrastructures were observed under the electron microscopy.</p><p><b>RESULTS</b>The IS was significantly smaller in Group H than that in Group IR [(25.40 ± 3.54)% compared with (38.27 ± 5.64)%, P<0.05]. The GST expression in myocardium was significantly higher in Group H than that in Group IR. Microscopic examination showed less myocardial damage in Group H than in Group IR. The protective effects of delayed preconditioning by hydrogen sulfide was prevented by 5-HD pre-treatment.</p><p><b>CONCLUSION</b>The hydrogen sulfide-induced delayed preconditioning attenuates myocardial IR injury possibly through up-regulating glutathione S-transferase expression in rats.</p>