Evaluation of DNA damage in construction-site workers occupationally exposed to welding fumes and solvent-based paints in Turkey.

In this study, the comet assay was used to evaluate whether welding fume and solvent base paint exposure led to DNA damage in construction-site workers in Turkey. The workers (n = 52) were selected according to their exposure in the construction site and controls (n = 26) from the general population, with no history of occupational exposure. The alkaline comet assay, a standard method for assessing genotoxicity, has been applied in peripheral lymphocytes of all subjects. The mean percentages of DNA in tail (%DNA(T)) of each group were evaluated, including the comparisons between smokers in each different group and the duration of exposure. Significant increase in the mean %DNA(T) (p < 0.01) was observed in all exposed subjects (12.34 ± 2.05) when compared with controls (6.64 ± 1.43). Also %DNA(T) was significantly high (p < 0.01) in welders (13.59 ± 1.89) compared with painters (11.10 ± 1.35). There was a statistical meaningful difference in % DNA(T) between control and exposed smokers. Our findings indicate that exposure to welding fumes and paints induce genotoxic effect in peripheral lymphocytes, indicating a potential health risk for workers. Therefore, to ensure maximum occupational safety, biomonitoring is of great value for assessing the risk for construction workers.

Comparision of biocompatibility and cytotoxicity of two new root canal sealers.

The aim of this study was to investigate the remote organ toxicity and connective tissue reaction of two new root canal sealers ("GuttaFlow(®)" and "EndoREZ(®)") and to compare them with zinc oxide eugenol sealer using biochemical and histopathological parameters. A total of 60 white albino Wistar rats were used in the study. 0.1ml of GuttaFlow(®), EndoREZ(®) or Kerr Pulp Canal Sealer(®) were administered subcutaneously into the mid-dorsal thoracic region of rats (15 in each group). Control rats were given saline only. Rats were decapitated after 24h, on day 7 and on day 30 of the experiment and tissue samples from lung, liver, kidney and skin were removed for the determination of malondialdehyde (MDA) and glutathione (GSH) levels. In parallel, tissues were also examined histologically. Serum aspartate aminotransferase (AST), alanine aminotransferase (ALT) levels, and creatinine and blood urea nitrogen (BUN), concentrations (BUN) were measured to assess liver and kidney functions, respectively. Tumor necrosis factor (TNF) and lactate dehydrogenase (LDH) were also assayed in serum samples. No statistical differences were found among the control and EndoREZ(®), GuttaFlow(®) and Kerr Pulp Canal sealers regarding tissue MDA, GSH levels or serum parameters (p>0.05) at all time points examined. Both of the new root canal sealers showed good compatibility and acceptable tissue toxicity.

Assessment of DNA damage in children exposed to indoor tobacco smoke.

The present study is aimed to evaluate the possible DNA damage in children who are living with smoker parents. The tests were conducted by using alkaline comet assay, measured as a percentage of DNA damage in tail (%DNA(T)). The children that participated in the study were selected from the pediatric unit of a hospital in Istanbul, Turkey. %DNA(T) was significantly higher (p<0.01) in children who were exposed to indoor tobacco smoke (10.73+/-1.38) compared to the children in the control group (8.16+/-1.29). The number of cigarettes consumed by household members did not seem to affect the severity of the DNA damage. Since children spend most of their time at home and cannot remove themselves from harmful living conditions this important genotoxic finding should be considered by smoker parents for the future health consequences of their children.

Protective effect of resveratrol against naphthalene-induced oxidative stress in mice.

OBJECTIVE: This investigation confirms the role of free radicals in naphthalene-induced toxicity and elucidates the mechanism of resveratrol (RVT). METHODS: Both male and female BALB-c mice were administered with naphthalene (100 mg/kg, i.p.) for 30 days, either along with saline or along with RVT (10mg/kg, orally). At the end of the experiment, following treatment and sacrifice of animals by decapitation, lung, liver and kidney tissue samples were taken for histological examination or determination of malondialdehyde (MDA), glutathione (GSH), myeloperoxidase (MPO) activity and collagen contents. Aspartate aminotransferase (AST), alanine aminotransferase (ALT), blood urea nitrogen (BUN) and creatinine levels and lactate dehydrogenase (LDH) activity were measured in the serum samples, while TNF-alpha, IL-beta, IL-6 and total antioxidant capacity (AOC) were assayed in plasma samples. RESULTS: Naphthalene administration caused a significant decrease in tissue GSH and plasma AOC, which was accompanied with significant increases in tissue MDA and collagen levels and MPO activity. Moreover, the pro-inflammatory mediators (TNF-alpha, IL-beta, IL-6), LDH activity, AST, ALT, creatinine and BUN levels were significantly increased in the naphthalene group. On the other hand, RVT treatment reversed all these biochemical indices as well as histopathological alterations induced by naphthalene. CONCLUSIONS: Oxidative mechanisms play an important role in naphthalene-induced tissue damage, and RVT, by inhibiting neutrophil infiltration, balancing oxidant-antioxidant status, and regulating the generation of inflammatory mediators, ameliorates oxidative organ injury due to naphthalene toxicity.

Melatonin protects against endosulfan-induced oxidative tissue damage in rats.

Endosulfan is a chlorinated cyclodiene insecticide which induces oxidative stress. In this study, we investigated the possible protective effect of melatonin, an antioxidant agent, against endosulfan (Endo)-induced toxicity in rats. Wistar albino rats (n = 8) were administered endosulfan (22 mg/kg/day orally) followed by either saline (Endo group) or melatonin (10 mg/kg/day, Endo + Mel group) for 5 days. In other rats, saline (control group) or melatonin (10 mg/kg/day, Mel group) was injected for 5 days, following corn oil administration (vehicle of endosulfan). Measurement of malondialdehyde (MDA) and glutathione (GSH) levels, myeloperoxidase (MPO) activity and collagen content were performed in liver and kidney. Furthermore, aspartate aminotransferase (AST), alanine aminotransferase (ALT), blood urea nitrogen (BUN), and creatinine levels, lactate dehydrogenase (LDH) activity were measured in the serum samples, while tumor necrosis factor-alpha (TNF-alpha), interleukin-beta (IL-beta) and total antioxidant capacity (AOC) were assayed in plasma samples. Endosulfan administration caused a significant decrease in tissue GSH and plasma AOC, which was accompanied with significant rises in tissue MDA and collagen levels and MPO activity. Moreover, the proinflammatory mediators (TNF-alpha and IL-beta), LDH activity, AST, ALT, creatinine and BUN levels were significantly elevated in the endosulfan-treated rats. On the other hand, melatonin treatment reversed all these biochemical alterations induced by endosulfan. Our results suggest that oxidative mechanisms play an important role in endosulfan-induced tissue damage and melatonin, by inhibiting neutrophil infiltration, balancing oxidant-antioxidant status and regulating the generation of inflammatory mediators, ameliorates oxidative organ injury as a result of endosulfan toxicity.

Fumonisins, trichothecenes and zearalenone in cereals.

Fumonisins are phytotoxic mycotoxins which are synthesized by various species of the fungal genus Fusarium such as Fusarium verticillioides (Sacc.) Nirenberg (ex F.moniliforme Sheldon) and Fusarium proliferatum. The trichothecene (TC) mycotoxins are secondary metabolites produce by species that belong to several fungal genera, especially Fusarium, Stachybotrys, Trichothecium, Trichoderma, Memnoniella and Myrothecium. Fusarium mycotoxins are widely dispersed in cereals and their products. Zearalenone (ZEA) is an estrogenic compound produced by Fusarium spp. such as F. graminearum and F. culmorum. Fumonisins, the TCs and ZEA are hazardous for human and animal health. Contamination with TCs causes a number of illnesses in human and animal such as decrease in food consumption (anorexia), depression or inhibition on immune system function and haematoxicity. The purpose of this paper is to give a review of the papers published on the field of fumonisin, TC and ZEA mycotoxins in cereals consumed in the world.

Occurrence of naphthalene in honey consumed in Turkey as determined by high-pressure liquid chromatography.

This study is the first report on an investigation of the naphthalene concentration in samples of contaminated honey consumed in Turkey. Naphthalene was detected using high-performance liquid chromatography with a diode array detector at 220 nm. In one suspected contaminated specimen, the presence of naphthalene was confirmed by gas chromatography with mass spectrometry (GC-MS) at a concentration of 1.13 microg/kg. The limit of detection was 0.023 microg/g and the limit of quantification was 0.078 microg/g with signal-to-noise ratios of 3 and 10, respectively. A total of 100 samples of commercially available honey obtained from markets (53 samples) and street bazaars (47 samples) were analyzed. Mean naphthalene recovery from honey known to be contaminated with 1 microg/g was 80.4% (SD = 4.84%, n = 7).

Ginkgo biloba extract protects against mercury(II)-induced oxidative tissue damage in rats.

Mercury(II) is a highly toxic metal which induces oxidative stress in the body. In this study we aimed to investigate the possible protective effect of Ginkgo biloba (EGb), an antioxidant agent, against experimental mercury toxicity in rat model. Following a single dose of 5mg/kg mercuric chloride (HgCl(2); Hg group) either saline or EGb (150mg/kg) was administered for 5days. After decapitation of the rats trunk blood was obtained and the tissue samples from the brain, lung, liver, and kidney were taken for the determination of malondialdehyde (MDA) and glutathione (GSH) levels, myeloperoxidase (MPO) activity and collagen contents. Formation of reactive oxygen species in the tissue samples was monitored by chemiluminescence (CL) technique. BUN, creatinin, ALT, and AST levels and tumor necrosis factor-alpha (TNF-alpha) and lactate dehydrogenase (LDH) activity were assayed in serum samples. The results revealed that HgCl(2) induced oxidative damage caused significant decrease in GSH level, significant increase in MDA level, MPO activity and collagen content of the tissues. Treatment of rats with EGb significantly increased the GSH level and decreased the MDA level, MPO activity, and collagen contents. Similarly, serum ALT, AST and BUN levels, as well as LDH and TNF-alpha, were elevated in the Hg group as compared to control group. On the other hand, EGb treatment reversed all these biochemical indices. Our results implicate that mercury-induced oxidative damage in brain, lung, liver, and kidney tissues protected by G. biloba extract, with its antioxidant effects.

Ginkgo biloba extract reduces naphthalene-induced oxidative damage in mice.

This investigation elucidated the role of free radicals in naphthalene-induced toxicity and protection by Ginkgo biloba extract (EGb). BALB-c mice of either sex were administered with naphthalene (100 mg/kg; i.p.) for 30 days, along with either saline or EGb (150 mg/kg, orally). At the end of the experiment, following decapitation, lung, liver and kidney tissue samples were taken for histological examination or determination of malondialdehyde (MDA), glutathione (GSH), myeloperoxidase (MPO) activity and collagen contents. In addition, proinflammatory cytokines (TNF-alpha and IL-beta) and total antioxidant capacity (AOC) were assayed in the plasma, while lactate dehydrogenase (LDH) activity was assayed in serum samples. The results revealed that naphthalene caused a significant decrease in GSH level, and significant increases in MDA level, MPO activity and collagen content of tissues. Similarly, plasma cytokines, as well as serum LDH activity, were elevated while AOC was decreased in the naphthalene group compared with the control group. On the other hand, EGb treatment reversed all these biochemical indices. The results demonstrate that EGb extract, by balancing the oxidant-antioxidant status and inhibiting the generation of proinflammatory cytokines and neutrophil infiltration, protects against naphthalene-induced oxidative organ injury.

Protective effects of ginkgo biloba against acetaminophen-induced toxicity in mice.

BACKGROUND: The analgesic acetaminophen (AAP) causes a potentially fatal, hepatic centrilobular necrosis when taken in overdose. It was reported that these toxic effects of AAP are due to oxidative reactions that take place during its metabolism. OBJECTIVE: In this study, we aimed to investigate the possible beneficial effect of Ginkgo biloba (EGb), an antioxidant agent, against AAP toxicity in mice. METHODS: Balb/c mice were injected i.p. with: (1) vehicle, control (C) group; (2) a single dose of 50 mg/kg Ginkgo biloba extract, EGb group; (3) a single dose of 900 mg/kg i.p. acetaminophen, AAP group, and (4) EGb, in a dose of 50 mg/kg after AAP injection, AAP + EGb group. Serum ALT, AST, and tumor necrosis factor-alpha (TNF-alpha) levels in blood and glutathione (GSH), malondialdehyde (MDA) levels, myeloperoxidase (MPO) activity, and collagen contents in liver tissues were measured. Formation of reactive oxygen species in hepatic tissue samples was monitored by using chemiluminescence (CL) technique with luminol and lusigenin probe. Tissues were also examined microscopically. RESULTS: ALT, AST levels, and TNF-alpha were increased significantly (p < 0.001) after AAP treatment, and reduced with EGb. Acetaminophen caused a significant (p < 0.05-0.001) decrease in GSH levels while MDA levels and MPO activity were increased (p < 0.001) in liver tissues. These changes were reversed by EGb treatment. Furthermore, luminol and lusigenin CL levels in the AAP group increased dramatically compared to control and reduced by EGb treatment (p < 0.01). CONCLUSION: Our results implicate that AAP causes oxidative damage in hepatic tissues and Ginkgo biloba extract, by its antioxidant effects protects the tissues. Therefore, its therapeutic role as a "tissue injury-limiting agent" must be further elucidated in drug-induced oxidative damage.

Protective effect of aqueous garlic extract against naphthalene-induced oxidative stress in mice.

The aim of this study was to investigate the possible protective effects of aqueous garlic extract (AGE) against naphthalene-induced oxidative changes in liver, kidney, lung and brain of mice. Balb/c mice (25-30 g) of either sex were divided into five groups each comprising 10 animals. Mice received for 30 days: 0.9% NaCl, i.p. (control); corn oil, i.p; AGE in a dose of 125 mg kg-1, i.p.; naphthalene in a dose of 100 mg kg-1, i.p. (dissolved in corn oil); and AGE (in a dose of 125 mg kg-1, i.p.) plus naphthalene (in a dose of 100 mg kg-1, i.p.). After decapitation, liver, kidney, lung and brain tissues were excised. Malondialdehyde (MDA) and glutathione (GSH) levels and myeloperoxidase activity (MPO) were determined in the tissues, while oxidant-induced tissue fibrosis was determined by collagen content. Tissues were also examined microscopically. Serum aspartate aminotransferase, alanine aminotransferase levels and blood urea nitrogen and creatinine concentrations were measured for the evaluation of hepatic and renal function, respectively. MDA and GSH levels were also assayed in serum samples. In the naphthalene-treated group, GSH levels decreased significantly, while MDA levels, MPO activity and collagen content increased in the tissues (P<0.01-0.001), suggesting oxidative organ damage, which was also verified histologically. In the AGE-treated naphthalene group, all of these oxidant responses were reversed significantly (P<0.05-0.01). Hepatic and renal function test parameters, which increased significantly (P<0.001) following naphthalene administration, decreased (P<0.05-0.001) after AGE treatment. The results demonstrate the role of oxidative mechanisms in naphthalene-induced tissue damage. The antioxidant properties of AGE ameliorated oxidative organ injury due to naphthalene toxicity.

Determination of fumonisins B1 and B2 in herbal tea and medicinal plants in Turkey by high-performance liquid chromatography.

The purpose of this study was to measure the potential levels of fumonisin B1 (FB1) and fumonisin B2 (FB2) contamination in several herbal teas and medicinal plants that are consumed regularly in Turkey. FB1 and FB2 were detected using high-performance liquid chromatography with fluorescence detection after derivatization with o-phthaldialdehyde. A total of 115 commercially available herbal tea and medicinal plant samples were analyzed. The recoveries in black tea were 86.9+/-8.42% for FB1 and 102+/-6.80% for FB2 spiked with 1 microg/g of each analyte. Similarly, the mean recovery results in lime (linden) for FB1 and FB2 were 85.2+/-9.76% and 78.6+/-5.67%, respectively. The minimum detectable amounts for the o-phthaldialdehyde derivatives of FB1 and FB2 were 0.025 microg/g (1 ng injected) and 0.125 microg/g (5 ng), respectively. FB1 was detected in two samples (0.160 and 1.487 microg/g), and FB2 was detected in none of the samples.