RESUMEN

This study was conducted to investigate the effect of the duration of a flaxseed diet on fattening pigs' antioxidant defence mechanism in blood and tissues. Eighteen 20-week-old Landrace breed fattening pigs (BW 76.61 ± 2.30 kg) were divided into three groups of six animals. The control group was fed a basal diet. The FS3 group was fed the basal diet supplemented with 10% flaxseed for 3 weeks. The FS6 group received the same basal diet with flaxseed for 6 weeks. The total antioxidant capacity of the blood, measured as the total antioxidant status (TAS), total plasma antioxidant capacity (FRAP), reactive oxygen metabolites (dROMs) and total antioxidant capacity (PAT), was not affected by the flaxseed diet. The superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione reductase (GR) activities were significantly decreased in the FS3 pigs in the heart (p < 0.05). However, in the FS3 group, the glutathione-S-transferase (GST) activity significantly increased compared to the control, but in the FS6 group, the activity was inhibited (p < 0.05). In the muscle, the CAT and GST activity was significantly decreased in the FS3 group (p < 0.05). The thiobarbituric acid reactive substance (TBARS) content was significantly reduced in the brain, muscle and heart in the FS3 group(p < 0.05). In FS6, the TBARS content significantly increased in the heart and brain (p < 0.05). Our results showed that the health effect of a flaxseed diet is significantly conditioned by the length of the flaxseed addition.

RESUMEN

We investigated the effects of dietary addition of sage extract on the biochemical parameters, weight of some body organs and changes in the counts of Salmonella Enteritidis PT4 (SE) in experimentally infected chickens. The following diets were used: basal diet, basal diet with addition of an extract of Salvia officinalis L. (S), basal diet and SE, and basal diet and S and SE (SSE). Compared to the SE group, sage extract in the SSE group decreased activities of ALP and ALT and concentrations of glucose and bilirubin on the 4th day post inoculation (p.i.). However, on the 18th day p.i., lower levels of bilirubin and ALT activity only were detected. Addition of sage extract to the diets decreased the counts of Salmonella in the liver, spleen and caecum at both sampling times, along with lower production of mucus in the chickens' intestines. Our results suggest that the addition of sage extract to the diet could be effective in protecting SE-infected chickens.

Asunto(s)

RESUMEN

Benzene is a relatively common environmental and occupational contaminant with carcinogenic and clastogenic properties. Therefore, further understanding of the adverse effect of benzene is still a matter of interest. In the present study, induction of aberrations in the pericentromeric region of chromosome 1 (1q12) was examined by fluorescence in situ hybridisation (FISH) in both interphase and metaphase human lymphocytes after in vitro exposure to benzene at two concentrations (50 and 100 mumol/l). A weak but not significant increase of interphase cells micronuclei frequency was recorded at 100 micromol/l concentration in both donors examined (chi(2) test, p > 0.05). No fluorescent signal indicating the presence of chromosome 1 was observed in adjacent micronuclei. In metaphase cells, hypoploidy (monosomy) and polyploidy (tetraploidy) were the types of numerical aberrations most often exhibiting classical satellite probe signal. Chromosome breakage in the investigated pericentromeric region was assumed in lymphocyte metaphase cultures of donor 2 exposed to a dose of 100 micromol/l.

Asunto(s)

RESUMEN

The effects of low doses of cyclohexanol exposure were studied in mouse bone marrow cells including chromosome aberrations (CA), micronucleus (MN) and sister chromatid exchanges (SCE) as biomarkers. Capillaries with a tested agent that was evaporated continuously were placed in an experimental chamber for six weeks. No clastogenic and/or aneugenic effect of CA and MN induction was observed. A significant elevation of induced damage was achieved in the SCE study (p < 0.001) that has confirmed the early exposure of cyclohexanol to mice.

Asunto(s)

RESUMEN

Adverse effects associated with occupational exposure to benzene have often been reported in humans. It has been shown, that benzene causes chromosomal aberrations, sister chromatid exchanges and micronuclei in lymphocytes of exposed workers. In addition to evidence by conventional cytogenetic methods, the genotoxic effect of benzene has also been proved by a more specific approach based on fluorescence in situ hybridization with DNA probes. In the present paper, the nature of benzene-induced chromosomal aberrations and supposed consequence on human health is reviewed. The new possibilities in chromosomal alterations identification by molecular cytogenetic methods are also presented.

Asunto(s)

RESUMEN

Benzene is a widespread human carcinogen, inducing leukaemia and hematotoxicity. It has been shown to be a multi-organ carcinogen in animals. The effect of benzene was studied using induction of micronuclei (MN) in whole blood lymphocytes cultures after treatment with different concentrations of benzene (5, 10, 50, 100, 500 and 1000 microM) with and without metabolic activation (S-9 mix). A significant elevation in the induction of micronuclei was found after application of benzene at doses of 50 and 100 microM in both donors. Treatment of bovine lymphocytes did not result in the induction of micronuclei in a dose-dependent manner. The addition of an external metabolic factor (10 % S-9 mix for 2 h) in blood cultures treated with benzene indicated an increase of the genotoxic activity of benzene (at concentrations ranging from 10-100 microM).

Asunto(s)