Search PubMed⌕ Search

Biomedical subjects

S Burgaz

Publications and source records attributed to S Burgaz.

30 records · Page 2Linked to original sources
PubMed1995

Evaluation of micronuclei in exfoliated urothelial cells and urinary thioether excretion of smokers.

Mutagens are present in large quantities in the urine of cigarette smokers, thus, their urothelial cells may represent a possible target for absorbed and excreted mutagens. Our aim is to validate the micronucleus (MN) test in exfoliated urothelial cells obtained from urine samples of cigarette smokers. The urinary thioether (UT) test is also carried out on the same individuals in order to find out whether there is any correlation between these two end-points. The mean (+/- SE) MN frequency and UT determination is 1.93 (+/- 0.11)% and 9.71 (+/- 1.61) mmol SH/mol creatinine for 23 smokers, and 0.66 (+/- 0.05)% and 4.20 (+/- 0.56) mmol SH/mol creatinine for 20 nonsmokers. Our results show a higher frequency of micronucleated cells (p < 0.001) and higher excretion of UTs (p < 0.05) in smokers as compared to nonsmokers. Concentrations of UTs and MN frequencies increased with tobacco consumption. The MN frequencies showed only a marginal increase, not significant (p > 0.05), after passive smoking compared to nonsmoking values. There was no significant correlation between MN frequencies and UTs, either in smokers (r = 0.164, p > 0.05) or in nonsmokers (r = -0.018, p > 0.05). Our data demonstrate tobacco-induced chromosome damage in bladder tissue consistent with increased risk of cancer at this site among smokers.

Adult↗
PubMed1994

Effect of hydroquinone (HQ) on the development of chick embryos.

The developmental toxic effect of hydroquinone (HQ) was evaluated in chick embryos after 72 and 96 hour of incubation. HQ was injected into the air sacs of the eggs at doses ranging from 0.0625 to 40 micrograms per egg. On the 15th day of incubation, live embryos including controls were removed from the eggs and examined for gross malformations and body hemorrhage. The LD50 values for HQ at 72 and 96 hours of incubation were 8.59 and 15.63 micrograms per egg, respectively. HQ produced gross malformations such as body hemorrhage, curled claws, everted viscera, defective beak, exencephaly and monophtalmia in developing chick embryos at dosages ranging from 20 to 0.0625 micrograms per egg in both groups. The various types of malformations and their incidences in both groups were higher in comparison with the controls, but were not statistically significant. At no concentration did malformations occur greater, than 35 percent for both 72 and 96 hours of incubation. The results of this study reveal that HQ is embryo toxic at higher doses and that teratogenic potential of HQ is unremarkable.

Abnormalities, Drug-Induced↗
PubMed1992

Evaluation of urinary excretion of 1-hydroxypyrene and thioethers in workers exposed to bitumen fumes.

Biological monitoring of exposure to bitumen fumes during road-paving operations was carried out. In order to evaluate the biological uptake of the workers, the nonselective urinary thioether assay and a selective method for the determination of urinary 1-hydroxypyrene were used. Urinary thioether data of exposed workers were higher than those of nonexposed subjects. The effect of smoking, however, was stronger than the effect of occupational exposure. Levels of 1-hydroxypyrene in road-paving workers were significantly higher than those in control subjects. The 1-hydroxypyrene level was also influenced by smoking habits, but the effect of occupational exposure was stronger. Our present data suggest that enhanced urine levels of both thioethers and 1-hydroxypyrene in bitumen workers may indicate an increased genotoxic risk. Furthermore, our results demonstrate the applicability of the 1-hydroxypyrene assay after occupational exposure to petroleum-based products.

Adult↗
PubMed1992

Thioethers in urine of sterilization personnel exposed to ethylene oxide.

Biological monitoring of exposure to ethylene oxide (EO) was carried out in 31 hospital workers in the sterilization facilities of five hospitals. The excretion of total thioethers was determined in the urine of sterilization workers. An occupational nonexposed group served as a control (n = 31). The air EO level was not monitored routinely, however, peak concentrations of EO up to 200 p.p.m. were detected mainly when the sterilization chambers were open. Our results show a significant difference in urinary thioether excretion between the exposed and control groups (P less than 0.001). Sterilization workers seem to absorb significant quantities of EO. We feel that other alternative and more sensitive methods for detecting thioether metabolites of EO should be carried out to confirm our results.

Adult↗
PubMed1988

Thioether excretion of workers exposed to bitumen fumes.

The excretion of thioethers was determined in the urine of workers involved in road paving operations and in the preparation of asphalt mixing in an asphalt plant. An occupationally nonexposed group served as control. From the results it was observed that there was no significant difference in urinary thioether levels between the exposed and nonexposed groups, however, smokers of both exposed groups had significantly higher urinary thioether levels than the nonexposed smoking workers. These results suggested that higher urinary thioether excretion could be only due to a difference in smoking behaviour. There were also significant differences in urinary thioether levels between the exposed smoking and nonsmoking workers. The authors suggest that these workers have a low mutagenic/carcinogenic risk and smoking is responsible for the majority of thioether excretion, as has been found by other investigators.

Adult↗
PubMed1988

A signal assay for the detection of genotoxic compounds: application on the urines of cancer patients on chemotherapy and of nurses handling cytotoxic drugs.

1. The excretion of thioethers was determined in the urine of nurses handling cytotoxic drugs (n = 10) and cancer patients under chemotherapy (n = 32). 2. An occupational non-exposed group served as control (n = 28). 3. We found no association between the handling of cytotoxic drugs and occupational exposure of nurses. Cancer patients under chemotherapy showed abnormally high values of thioethers, while urinary thioether concentration was, consistently, rather low in some individuals under intensive chemotherapy. 4. We conclude that periodical urinary thioether determinations should be made available to hospital staff as well as cancer patients to minimize the risks of the cytotoxic drugs.

Adolescent↗
PubMed1987

Urinary thioether excretion in nurses at an oncologic department.

The excretion of thioethers was determined in urine of nurses who were handling cytotoxic drugs. An occupationally non-exposed group served as control. The results showed a significant difference in urinary thioether excretion between the exposed and control persons (P less than 0.05). In both groups, however, higher thioether excretion was found in smokers; both exposed smoking nurses and smoking controls had significantly higher urinary thioether levels than the non-smoking exposed and control persons. The results suggested a synergistic effect of smoking with exposure to cytostatic drugs: thioether excretion of urine from exposed smokers was significantly higher than that of control smokers (P less than 0.05). There was no difference in urinary thioether levels between the non-smoking exposed and control persons (P greater than 0.05). In conclusion, smoking nurses handling cytostatic drugs, have a greater risk than non-smoking colleagues and protective intervention methods should be used by smoking as well as non-smoking hospital employees.

Adult↗