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Zinc oxide enhancement of chemiluminescence in rat neutrophils
Poster Session 2F. Metals and Na2B407 against fluoride ions was compared in goats after simultaneous oral administration of single dose of NaP (20 mglkg b.w) and salt solution in equinormal concentration, in separate experiments in adult male goats. Various toxicokinetic parameters on comparison indicated, reduced and slow absorption of fluoride ions with the treatment of various salts, but Na2B407 was significantly (P < 0.05) less effective to reduce the bioavailability of fluoride ions (21.65 ± 2.19%) as compared to other salts. The combination of two salts could also ameliorate fluoride ions but no significant improvement over ameliorative efficacy of individual salt could be achieved, whereas, the combination of salts containing Na2B4~ with AlCl) and MgCl2 were significantly less effective against fluoride ions for amelioration and bioavailability of fluoride ions was (34.35 ± 4.53% for MgCh and 30.23 ± 4.36% for AlCI3) significantly high as compared to the combinations not containing Na2B407 with MgCl2 and AlCl), respectively. It is an indication of synthesis of various borates due to the presence of borax (Na2B407) in the gut of goats. The present study confirms the ability of toxicokinetic models for ameliorative study of various toxicants.
1P2F1741
ZINCOXIDEENHANCEMENT OF CHEMILUMINESCENCE IN RAT NEUTROPHILS
K. Ogino *1, T. Hiramatsu 1 , M. Inagaki ' , H. Nagase 1 , H. Nakamura1 , M. Okuda2 , T. Houbara''. 1 Department ofPublic Health, Faculty ofMedicine, Kanazawa University, Kanazawa; 2 Department ofPublic Health, Yamaguchi University School of Medicine, Ube, Japan It has been demonstrated that inhalating zinc oxide induces cytokine production in bronchoalveolar lavage in vivo. However, the cellular activation mechanisms of phagocytes by zinc oxide are unknown. Therefore, we investigated the effect of zinc oxide on the activation of neutrophils by chemiluminescence (CL). Zinc oxide enhanced luminol-dependent CL without calcium ions in the medium. The enhanced CL was augmented by thiol compounds like glutathione (GSH) and dithiothreitol. Superoxide dismutase inhibited zinx oxide-induced CL remarkably but did not inhibit CL induced by zinc oxide plus GSH. Catalase, 4,5-dihydroxy-I,3-benzene disulfonic acid (tiron, a low molecular weight scavenger of 02-), 1-(5-isoquinolinesulfonyl)-2-methylpiperazine (H-7, a protein kinase C inhibitor), 4', 5, 7-trihydroxyisoflavone (genistein, a protein tyrosine kinase inhibitor), and an intracellular calcium chelator, 0,0' -bis(2-aminophenyl)ethyleneglycol-N, N, N, N-tetraacetic acid (BAPTA), inhibited zinc oxide and zinc oxide plus GSH-induced CL. These results suggest that zinc oxide plus GSH stimulates intracellual origin of 02-production.
1P2F175 1 INDUCTION OF METALLOTHIONEIN BY ANTIOXIDANTS - A POSSIBLEPROTECTIVE MECHANISM AGAINSTMETALTOXICITY S.V.S. Rana. Toxicology Lab, Zoology Department, Ch. Charan Singh University, Meerut, 250004, India Metallothionein (MT) is a low molecular-weight protein involved in detoxication of heavy metals. It has been estimated in the liver and kidney of cadmium and mercury treated rats offered antioxidative protection by selenium (Se), vitamin E and glutathione (GSH). It was observed that antioxidants stimulated induction of MT in these rats. Induction was found to be greater in kidney than liver. Se induced maximum synthesis of MT in the kidney of mercury treated rats whereas maximum synthesis of MT in Cd fed rats was observed after GSH treatment. It is suggested that different metal species induce specific metallothionein (s) that express specific effects. The mechanism for maintaining high levels of MT might result from increased translation and transcription of MT. There seems to be no
137
direct explaination for increased induction of MT by antioxidants. Interleukin-I and interferon also induce MT. Hormonal changes including glucagon and glucocorticoids are also known to stimulate MT synthesis. Present experimental evidence tend to suggest that these proteins not only scavenge free radicals, decrease accumulation of metals in soft tissues but might offer protection by yet unknown mechanism(s).
IP2F1761
ACUTETHALLIUMPOISONING AND ITS TREATMENT WITHTWOCASESREPORT
Jin-yuan Zhao *, Xi-xian Xu, Li-jun Mao. Research Center of Occupational Medicine, The Third Teaching Hospital ofBeijing Medical University, Beijing 100083, P.R. China Two male college students were heavily poisoned by thallium owing to murder. They took 500 mg and 700 mg thallium sulfate per os in 1 and 7 days respectively, and had nausea, vomiting, dirrhea, abdominal pain and fatigue immediately, accompanied with insensibility and pain in extremities, especially the lowers. One week later, baldness and trichomade occurred, then the ocular neuritis from the 4th week of poisoning. The plasma thallium and urine thallium were more than 600 Jlg/L and 100 Jlg/L two days later after last ingestion respectively. All the toxic manifestations including digestive and peripheral nervous symptoms, even baldness were abated in 14 days after treatment. The patients well recovered in 2 months except slight hypopsia. The clinical data suggests that the thiol chelator such as DM-PS, DMS etc. (i.m or i.v) and Prusian blue (per os) are effective thalliumexpelling measures which may have plasma thallium reduced to less than 30 Jlg/L, and urine thallium increased by one fold after two day application; that the selenium, reduced glutathione, ATP, potassium and insulin are necessary in improving symptoms and accelerating recovery; but that the hemodialysis only plays little role in cleaning thallium from human body, because there was no significant change in plasma thallium after hemodialysis.
1P2F177 1 URINARY NICKELAS BIOINDICATOR OF Ni EXPOSURE OF WORKERS IN A GALVANIZING PLANT IN BRAZIL M.E.P.B. Siqueira *, J.P. Oliveira. College ofPharmacy and Dentistry ofAlfenas/Volkswagen do Brasil, Alfenas, MG, Brazil We have measured urinary nickel (V-Ni)/creatinine ratios in 10 workers (97 samples) from a galvanizing plant that uses nickel sulphate, and 10 controls (55 samples) to examine the association between ocupational exposure to airborne Ni and Ni absorption. Samples from the exposed group were taken in the morning and in the afternoon during a 5-day workshift. At the same time the evaluation of airborne Ni (A-Ni) using personal samplers was performed. Ni levels in biological material and in air were determined by graphite furnace atomic absorption spectrometry validated method. In the control group of the non-exposed workers the urine samples were collected twice a day, in the morning and afternoon, during 3 days. The exposure to Ni may be considered low to moderate in the all evaluated places of the plant, the air levels varying between 5.8 to 85.3 Jlg/m 3 and the urine levels, from samples taken post-shift, between 4.5 and 43.2 Jlg/g creatinine (mean 14.7 Jlg/g creatinine). Significant differences were seen between exposed and control groups for U-Ni creatinine ratios (Student t test, p ::'0 0.05). Significant correlation between U-Ni and A-Ni (r = 0.959; P ::'0 0.0001) shows that Ni-U may be used as a good indicator of internal dose in the biological monitoring of workers exposed to Ni sulphate in galvanizing plants.
1P2F1741
ZINCOXIDEENHANCEMENT OF CHEMILUMINESCENCE IN RAT NEUTROPHILS
K. Ogino *1, T. Hiramatsu 1 , M. Inagaki ' , H. Nagase 1 , H. Nakamura1 , M. Okuda2 , T. Houbara''. 1 Department ofPublic Health, Faculty ofMedicine, Kanazawa University, Kanazawa; 2 Department ofPublic Health, Yamaguchi University School of Medicine, Ube, Japan It has been demonstrated that inhalating zinc oxide induces cytokine production in bronchoalveolar lavage in vivo. However, the cellular activation mechanisms of phagocytes by zinc oxide are unknown. Therefore, we investigated the effect of zinc oxide on the activation of neutrophils by chemiluminescence (CL). Zinc oxide enhanced luminol-dependent CL without calcium ions in the medium. The enhanced CL was augmented by thiol compounds like glutathione (GSH) and dithiothreitol. Superoxide dismutase inhibited zinx oxide-induced CL remarkably but did not inhibit CL induced by zinc oxide plus GSH. Catalase, 4,5-dihydroxy-I,3-benzene disulfonic acid (tiron, a low molecular weight scavenger of 02-), 1-(5-isoquinolinesulfonyl)-2-methylpiperazine (H-7, a protein kinase C inhibitor), 4', 5, 7-trihydroxyisoflavone (genistein, a protein tyrosine kinase inhibitor), and an intracellular calcium chelator, 0,0' -bis(2-aminophenyl)ethyleneglycol-N, N, N, N-tetraacetic acid (BAPTA), inhibited zinc oxide and zinc oxide plus GSH-induced CL. These results suggest that zinc oxide plus GSH stimulates intracellual origin of 02-production.
1P2F175 1 INDUCTION OF METALLOTHIONEIN BY ANTIOXIDANTS - A POSSIBLEPROTECTIVE MECHANISM AGAINSTMETALTOXICITY S.V.S. Rana. Toxicology Lab, Zoology Department, Ch. Charan Singh University, Meerut, 250004, India Metallothionein (MT) is a low molecular-weight protein involved in detoxication of heavy metals. It has been estimated in the liver and kidney of cadmium and mercury treated rats offered antioxidative protection by selenium (Se), vitamin E and glutathione (GSH). It was observed that antioxidants stimulated induction of MT in these rats. Induction was found to be greater in kidney than liver. Se induced maximum synthesis of MT in the kidney of mercury treated rats whereas maximum synthesis of MT in Cd fed rats was observed after GSH treatment. It is suggested that different metal species induce specific metallothionein (s) that express specific effects. The mechanism for maintaining high levels of MT might result from increased translation and transcription of MT. There seems to be no
137
direct explaination for increased induction of MT by antioxidants. Interleukin-I and interferon also induce MT. Hormonal changes including glucagon and glucocorticoids are also known to stimulate MT synthesis. Present experimental evidence tend to suggest that these proteins not only scavenge free radicals, decrease accumulation of metals in soft tissues but might offer protection by yet unknown mechanism(s).
IP2F1761
ACUTETHALLIUMPOISONING AND ITS TREATMENT WITHTWOCASESREPORT
Jin-yuan Zhao *, Xi-xian Xu, Li-jun Mao. Research Center of Occupational Medicine, The Third Teaching Hospital ofBeijing Medical University, Beijing 100083, P.R. China Two male college students were heavily poisoned by thallium owing to murder. They took 500 mg and 700 mg thallium sulfate per os in 1 and 7 days respectively, and had nausea, vomiting, dirrhea, abdominal pain and fatigue immediately, accompanied with insensibility and pain in extremities, especially the lowers. One week later, baldness and trichomade occurred, then the ocular neuritis from the 4th week of poisoning. The plasma thallium and urine thallium were more than 600 Jlg/L and 100 Jlg/L two days later after last ingestion respectively. All the toxic manifestations including digestive and peripheral nervous symptoms, even baldness were abated in 14 days after treatment. The patients well recovered in 2 months except slight hypopsia. The clinical data suggests that the thiol chelator such as DM-PS, DMS etc. (i.m or i.v) and Prusian blue (per os) are effective thalliumexpelling measures which may have plasma thallium reduced to less than 30 Jlg/L, and urine thallium increased by one fold after two day application; that the selenium, reduced glutathione, ATP, potassium and insulin are necessary in improving symptoms and accelerating recovery; but that the hemodialysis only plays little role in cleaning thallium from human body, because there was no significant change in plasma thallium after hemodialysis.
1P2F177 1 URINARY NICKELAS BIOINDICATOR OF Ni EXPOSURE OF WORKERS IN A GALVANIZING PLANT IN BRAZIL M.E.P.B. Siqueira *, J.P. Oliveira. College ofPharmacy and Dentistry ofAlfenas/Volkswagen do Brasil, Alfenas, MG, Brazil We have measured urinary nickel (V-Ni)/creatinine ratios in 10 workers (97 samples) from a galvanizing plant that uses nickel sulphate, and 10 controls (55 samples) to examine the association between ocupational exposure to airborne Ni and Ni absorption. Samples from the exposed group were taken in the morning and in the afternoon during a 5-day workshift. At the same time the evaluation of airborne Ni (A-Ni) using personal samplers was performed. Ni levels in biological material and in air were determined by graphite furnace atomic absorption spectrometry validated method. In the control group of the non-exposed workers the urine samples were collected twice a day, in the morning and afternoon, during 3 days. The exposure to Ni may be considered low to moderate in the all evaluated places of the plant, the air levels varying between 5.8 to 85.3 Jlg/m 3 and the urine levels, from samples taken post-shift, between 4.5 and 43.2 Jlg/g creatinine (mean 14.7 Jlg/g creatinine). Significant differences were seen between exposed and control groups for U-Ni creatinine ratios (Student t test, p ::'0 0.05). Significant correlation between U-Ni and A-Ni (r = 0.959; P ::'0 0.0001) shows that Ni-U may be used as a good indicator of internal dose in the biological monitoring of workers exposed to Ni sulphate in galvanizing plants.