Observation on the protective effect of hyperoxia solution on the acute lung injury caused by phosgene poisoning / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study the protective effect of hyperoxia solution on acute lung injury caused by phosgene poisoning by observing the changes of PaO2 and malondialdehyde (MDA) contents, superoxide dismutase (SOD) activity in serum and Glutathione (GSH/GSSG) contents in lung tissues.</p><p><b>METHODS</b>The rabbits were divided into normal control group, hyperoxia solution (H0) and balance salt (BS) groups. Group HO and Group BS inhaled phosgene and the former was given intravenously hyperoxia solution (which was replaced by balance salt solution in Group BS). The content of MDA and the activity of SOD in serum were observed at different time points, the amount of GSH and GSSG in lung tissue were also measured.</p><p><b>RESULTS</b>(1) The serum MDA contents increased and PaO2, SOD activity decreased significantly in Group HO and Group BS along with time increasing as compared with control group. The contents of GSH in lung tissue decreased in two groups compared with that in control group, however the contents of GSSG ascended instead. (2) At 3 and 8 h of the experiment, PaO2 of Group HO [(9.91 +/- 0.49), (9.15 +/- 0.46) mm Hg respectively] were significantly higher than those of Group BS [(9.03 +/- 0.76), (8.11 +/- 0.57) mm Hg respectively] (P < 0.01). The contents of MDA of Group HO (3.66 +/- 0.35), (5.31 +/- 0.15) micromol/L respectively] were lower than those of Group BS [(4.32 +/- 0.26), (7.4 +/- 0.33) micromol/L respectively] (P < 0.01). SOD activity in Group HO [(237.37 +/- 29.96), (208.10 +/- 18.80) NU/ml respectively] were higher than those of Group BS [(195.02 +/- 21.44), (144.87 +/- 21.26) NU/ml respectively] (P < 0.05 or P < 0.01). The content of GSSG lung tissue in Group HO (423.67 +/- 38.21) micromol/L were lower than those of Group BS (523.85 +/- 43.14) mol/L (P < 0.01). There were no significant differences in the content of GSH in lung tissues between Group HO and group BS.</p><p><b>CONCLUSION</b>Hyperoxia solution can reduce acute lung injury of rabbits following phosgene poisoning.</p>

Effect of phosgene on apoptosis of alveolar type II cells and vascular endothelial growth factor in exposed mice / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study the apoptosis of alveolar type II cells, alterations of vascular endothelial growth factor (VEGF), VEGF receptor (Flt1) in serum and lung and expression of VEGF mRNA in lung in pulmonary edema mice induced by phosgene.</p><p><b>METHODS</b>Twenty-six BALB/C mice were randomly divided into 2 groups: control group, exposed group (13 mice in each group). Mice of exposed group were intoxicated by inhalation of phosgene 11.9 mg/L for 5 minutes. Mice of control group were treated as the same way by inhalation of air. Isolation of mice alveolus type II cells 4 h after intoxication was carried out to observe their apoptosis under electron microscope. Contents of VEGF and Flt1 in lung and serum by ELISA, and expression of VEGF mRNA were determined.</p><p><b>RESULTS</b>Alveolar type II cells were identified by tannic acid staining and electron microscopy. After exposed to 11.9 mg/L of phosgene for 5 minutes, the apoptotic body in alveolus type II cells was found in exposed group. The contents of VEGF in serum and lung and Flt1 in lung of exposed mice [(134.07 +/- 120.26), (477.76 +/- 98.06), (1,2818.48 +/- 2,304.15) pg/ml] were significantly lower than those of control group [(445.57 +/- 173.30), (1,026.87 +/- 474.56), (21,976.51 +/- 7,421.01) pg/ml, P < 0.05] but the content of Flt1 in serum [(2,369.56 +/- 381.70) pg/ml] was higher than that in control group [(1,898.00 +/- 453.69) pg/ml, P < 0.05]. The expression of VEGF mRNA in pulmonary edema mice was decreased.</p><p><b>CONCLUSION</b>Phosgene can induce apoptosis of alveolar type II cells, and decrease in the content of VEGF and Flt1, and expression of VEGF mRNA in lung.</p>

Effect of acute phosgene inhalation on antioxidant enzymes, nitric oxide and nitric-oxide synthase in rats / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study the effect of acute phosgene inhalation on the antioxidant enzymes, nitric oxide (NO) and nitric oxide synthase (NOS) in rats.</p><p><b>METHODS</b>Phosgene was produced by decomposing bis (trichdomethyl) carbonate in the presence of N,N-dimethyl formamide. SD rats were randomly divided into two groups: control and phosgene exposure groups. In a special experimental device with equipment modulating the gas flow, phosgene exposed rats inhaled phosgene quantitatively for five minutes. Two hours later, all the rats were sacrificed and the ratio of wet weight to dried weight of lung (WW/DW) was calculated. Peripheral blood, serum and liver were collected to examine the activities of antioxidant enzymes including glutathione S-transferase (GST), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), NOS, and NO level. The total content of proteins were also determined.</p><p><b>RESULTS</b>The WW/DW ratio of lung in phosgene exposure group was much higher than that in control group (P < 0.01). The activities of GST in serum and liver of phosgene exposure group increased significantly (P < 0.05). The activities of SOD, CAT, GSHPx and NOS in serum or blood and liver of phosgene exposure group were also increased significantly (P < 0.05). But the content of NO was significantly decreased (P < 0.01).</p><p><b>CONCLUSION</b>Acute phosgene inhalation may cause a dramatically changes of several antioxidant enzyme activities, and acute injury of liver to some extent in rats. The latter is related to reactive oxygen species. But the elevation of antioxidant enzyme activities suggests that antioxidative treatment for acute phosgene poisoning should not be considered first.</p>

Effect of modified ricin on the reduction of hepatotoxicity in mice / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To observe the significance of ricin (RT) with chemical nidification to reduce the hepatotoxicity in mice and its anticancer effect.</p><p><b>METHODS</b>Mice were exposed to RT and RT-PDP [ricin chemically modified by N-succinimidyl 3-(2-pyridyldithio)-propionate, (SPDP)] respectively, and their serum activity of glutathione-S-transferase (GST) and liver glutathione (GSH) content were determined. The ultramicro-structure under electron microscope was also observed.</p><p><b>RESULTS</b>The GST activity increased with doses, and the increase in ricin group was higher than that in RT-PDP group; the activities of GST in RT group at 12.5, 15.0 micro g/kg [(93.65 +/- 12.30), (153.71 +/- 26.64) IU/L respectively] were higher than those in RT-PDP group [(62.97 +/- 11.22), (78.20 +/- 15.71) IU/L] (P < 0.05). The contents of GSH were decreased with doses; but the contents of GSH in RT-PDP group at 2.5, 5.0, 7.5, 10.0, 15.0 micro g/kg [(6.34 +/- 1.43), (4.14 +/- 1.82), (3.54 +/- 0.64), (2.73 +/- 1.82), (1.82 +/- 0.62) micro mol/L respectively] were still higher than those in RT group [(3.53 +/- 0.95), (2.12 +/- 0.54), (1.82 +/- 0.71), (1.52 +/- 0.34), (0.81 +/- 0.36) micro mol/L] (P < 0.01). Electron microscopic examination showed that the injury of liver cells in RT group was more severe than that in RT-PDP group.</p><p><b>CONCLUSION</b>The hepatotoxicity of ricin in mice may be reduced by chemical modification.</p>

The effects of ultraviolet blood irradiation and oxygenation on oxygen free radical metabolism in rabbits with soman intoxication / 中华物理医学与康复杂志

Objective To investigate the effects of ultraviolet blood irradiation and oxygenation(UBIO)on oxygen free radical metabolism(OFRM)in rabbits with acute soman intoxication.Methods One hundred rabbits were randomly divided into five groups:a control group,a soman intoxication group(I),a soman intoxication plus routine therapy group(TR),a soman intoxication plus UBIO therapy group(UBIO)and a soman intoxication plus complex therapy group(CT).All the rabbits were intervened accordingly.Then the concentrations of malondiade- hyde(MDA)and the activities of superoxide dismutase(SOD),glutathionperoxidase(GSH Px)and catalase (CAT)in serum were determined at 14 d after various treatments.Results Compared with the control group,the concentration of MDA and the activity of CAT in the 1 group were significantly increased(P＜0.01),while the activi- ties of SOD and GSH Px were obviously decreased(P＜0.05).After UBIO or complex therapy,the serum level of MDA was significantly decreased in comparison with that in the I group(P＜0.01),while the concentrations of SOD, GSH Px and CAT were enhanced(P＜0.05).Conclusion UBIO therapy can improve antioxidation activity against the injury caused by free radicals and could be used to treat acute soman intoxication,which causes injury from in- creased oxygen free radical concentrations.