Lack of genotoxicity induced by endogenous and synthetic female sex hormones in peripheral blood cells detected by alkaline Comet assay

The etiology of hormone-induced cancers has been considered to be a combination of genotoxic and epigenetic events. Currently, the Comet assay is widely used for detecting genotoxicity because it is relatively simple, sensitive, and capable of detecting various kinds of DNA damage. The present study evaluates the genotoxic potential of endogenous and synthetic sex hormones, as detected by the Comet assay. Blood cells were obtained from 12 nonsmoking and 12 smoking women with regular menstrual cycles and from 12 nonsmoking women taking low-dose oral contraceptives (OC). Peripheral blood samples were collected at three phases of the menstrual cycle (early follicular, mean follicular, and luteal phases), or at three different moments of oral contraceptive intake. Three blood samples were also collected from 12 healthy nonsmoking men, at the same time as oral contraceptive users. Results showed no significant difference in the level of DNA damage among the three moments of the menstrual cycle either in nonsmoking and smoking women, or between them. No significant difference in DNA damage was also observed among oral contraceptive users, nonusers, and men. Together, these data indicate lack of genotoxicity induced by the physiological level of the female sex hormones and OC as assessed by the alkaline Comet assay. In conclusion, normal fluctuation in endogenous sex hormones and use of low-doses of oral contraceptive should not interfere with Comet assay data when this technique is used for human biomonitoring.

Absence of DNA damage in multiple organs (blood, liver, kidney, thyroid gland and urinary bladder) after acute fluoride exposure in rats

Fluoride has been widely used in dentistry as a caries prophylactic agent. However, there has been some speculation that excess fluoride could cause an impact on genome integrity. In the current study, the potential DNA damage associated with exposure to fluoride was assessed in cells of blood, liver, kidney, thyroid gland and urinary bladder by the single cell gel (comet) assay. Male Wistar rats aging 75 days were distributed into seven groups: Groups 1 (control), 2, 3, 4, 5, 6 and 7 received 0 (deionized water), 10, 20, 40, 60, 80 and 100 mgF/Kg body weight from sodium fluoride (NaF), respectively, by gastrogavage. These groups were killed at 2 h after the administration of the fluoride doses. The level of DNA strand breaks did not increase in all organs evaluated and at all doses of NaF tested, as depicted by the mean tail moment. Taken together, our results suggest that oral exposure to NaF did not result in systemic genotoxic effect in multiple organs related to fluoride toxicity. Since DNA damage is an important step in events leading to carcinogenesis, this study represents a relevant contribution to the correct evaluation of the potential health risk associated with chemical exposure.

Stable isotopes for determining carbon turnover in sheep feces and blood

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Recovery of high blood pressure after chronic lesions of the commissural NTS in SHR

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Low-level laser therapy (670 nm) on viability of random skin flap in rats

This study investigated the effects of 670 nm laser, at different fluences, on the viability of skin flap in rats. One hundred male animals were used. The animals were divided into control group; group treated with 3 J/cm(2); group treated with 6 J/cm(2); group treated with 12 J/cm(2) and group treated with 24 J/cm(2). The skin flap was made on the backs of all animals studied, with a plastic sheet interposed between the flap and the donor site. Laser irradiation was done immediately after the surgery and on days 1, 2, 3 and 4 after surgery. The percentage of necrosis of the flap was calculated at the 7th postoperative day. Additionally, a sample of each flap was collected to enable us to count the blood vessels. Treated animals showed a statistically significant smaller area of necrosis than did the control group. The necrosis in the treated groups was 41.82% (group 2), 36.51% (group 3), 29.45% (group 4) and 20.37% (group 5). We also demonstrated that laser irradiation at 670 nm, at all doses used, had a stimulatory effect on angiogenesis. Our study showed that the 670 nm laser was efficient to increase the viability of the skin flap, at all fluences used, with a tendency of reaching better results at higher doses.

The effect of propolis on CCL5 and IFN-gamma expression by peripheral blood mononuclear cells from leishmaniasis patients

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Effect of soccer training on the running speed and the blood lactate concentration at the lactate minimum test

Tegtbur et al. [23] devised a new method able to estimate the intensity at maximal lactate steady state termed lactate minimum test. According to Billat et al. [7], no studies have yet been published on the affect of training on highest blood lactate concentration that can be maintained over time without continual blood lactate accumulation. Therefore, the aim of the present study was to verify the effect of soccer training on the running speed and the blood lactate concentration (BLC) at the lactate minimum test (Lac(min)). Thirteen Brazilian male professional soccer players, all members of the same team playing at National level, volunteered for this study. Measurements were carried out before (pre) and after (post) eight weeks of soccer training. The Lac(min) test was adapted to the procedures reported by Tegtbur et al. [23]. The running speed at the Lac(min) test was taken when the gradient of the line was zero. Differences in running speed and blood lactate concentration at the Lac(min) test before (pre) and after (post) the training program were evaluated by Student's paired t-test. The training program increased the running speed at the Lac(min) test (14.94 +/- 0.21 vs. 15.44 +/- 0.42* km(.)h(-1)) and the blood lactate concentration (5.11 +/- 2.31 vs. 6.93 +/- 1.33* mmol(.)L(-1)). The enhance in the blood lactate concentration may be explained by an increase in the lactate/H+ transport capacity of human skeletal muscle verified by other authors.

Expression of annexin A1 mRNA in peripheral blood from oral squamous cell carcinoma patients

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Serum melatonin level and oxidative stress in sickle cell anemia

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Ex vivo evaluation of the effectiveness of bleaching agents on the shade alteration of blood-stained teeth

Aim To evaluate ex vivo effectiveness of the three formulations of bleaching materials for intracoronal bleaching of root filled teeth using the walking bleach technique.Methodology Extracted premolar teeth were stained artificially with human blood. After biomechanical preparation, the root canals were filled and a 3-mm thick intermediate base of zinc phosphate cement was placed at the level of the cementoenamel junction. The teeth were divided into four groups (n = 12): C (control, without bleaching material), A1 (sodium perborate + distilled water), A2 (sodium perborate + 10% carbamide peroxide) and A3 (sodium perborate + 35% carbamide peroxide). The bleaching materials were changed at 7 and 14 days. Evaluation of shade was undertaken with aid of the VITA Easyshade (TM) (Delta E*ab) and was performed after tooth staining and at 7, 14 and 21 days after bleaching, based on the CIELAB system. Data were analysed by ANOVA for repeated measurements, Tukey and Dunnett tests (alpha = 0.05).Results The Tukey test revealed that group A1 (10.58 +/- 4.83 Delta E*ab) was statistically different from the others (A2, 19.57 +/- 4.72 Delta E*ab and A3, 17.58 +/- 3.33 Delta E*ab), which were not different from each other. At 7 days: A1 was significantly different from A2; at 14 and 21 days: A2 and A3 were significantly better than A1; the Dunnett test revealed that the control group was different from A1, A2 and A3 at all periods (P < 0.05).Conclusion Sodium perborate associated with both 10% and 35% carbamide peroxide was more effective than when associated with distilled water.

Apoptosis in T lymphocytes from spleen tissue and peripheral blood of L. (L.) chagasi naturally infected dogs

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Direct and Simultaneous Determination of Cd Cu, and Se in Blood Samples by Graphite Furnace Atomic Absorption Spectrometry

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Serum leptin level in hypertensive middle-aged obese women

The mechanism by which adiposity can raise blood pressure is not fully understood. Leptin has been suggested as a possible cause of the arterial hypertension in obese subjects because leptin induces an increase in sympathetic activity. The aim of the present study is to evaluate serum leptin level, blood pressure, lipid profile, blood glucose, and insulin in obese women. Leptin, total cholesterol, low-density lipoprotein (LDL) cholesterol, and triglycerides were measured. Serum leptin was markedly higher in hypertensive obese women (92.3 +/- 22 ng/mL, n = 7) as compared with normotensive obese women (37.7 +/- 11 ng/mL, n = 7). Similarly, total cholesterol and LDL cholesterol were significantly elevated in the hypertensive group. No changes were observed in triglycerides and high-density lipoprotein cholesterol concentration between the 2 groups. There were no significant differences in plasma insulin concentration or blood glucose in both groups. In conclusion, our findings suggest a link among dyslipidemia, leptin level, and hypertension that might be relevant to the development of cardiovascular disease in obese subjects.

Effects of recovery type after a judo combat on blood lactate removal and on performance in an intermittent anaerobic task

Aim. The objective of this study was to verify the effects of active (AR) and passive recovery (PR) after a judo match on blood lactate removal and on performance in an anaerobic intermittent task (4 bouts of upper body Wingate tests with 3-min interval between bouts; 4WT).Methods. The sample was constituted by 17 male judo players of different competitive levels: A) National (Brazil) and International medallists (n. 5). B) State (São Paulo) medallists (n. 7). Q City (São Paulo) medallists (n. 5). The subjects were submitted to: 1) a treadmill test for determination of VO2peak and velocity at anaerobic threshold (VAT); 2) body composition; 3) a 5-min judo combat, 15-min of AR or PR followed by 4WT.Results. The groups did not differ with respect to: body weight, VO2peak, VAT, body fat percentage, blood lactate after combats. No difference was observed in performance between AR and PR, despite a lower blood lactate after combat (10 and 15 min) during AR compared to PR. Groups A and B performed better in the high-intensity intermittent exercise compared to athletes with lower competitive level (C).Conclusion. The ability to maintain power output during intermittent anaerobic exercises can discriminate properly judo players of different levels. Lactate removal was improved with AR when compared to PR but AR did not improve performance in a subsequent intermittent anaerobic exercise.

DIAGNOSIS of REGIONAL CEREBRAL BLOOD FLOW ABNORMALITIES USING SPECT: AGREEMENT BETWEEN INDIVIDUALIZED STATISTICAL PARAMETRIC MAPS and VISUAL INSPECTION BY NUCLEAR MEDICINE PHYSICIANS WITH DIFFERENT LEVELS of EXPERTISE IN NUCLEAR NEUROLOGY

INTRODUCTION: Visual analysis is widely used to interpret regional cerebral blood flow (rCBF) SPECT images in clinical practice despite its limitations. Automated methods are employed to investigate between-group rCBF differences in research Studies but have rarely been explored in individual analyses.OBJECTIVES: To compare visual inspection by nuclear physicians with the automated statistical parametric mapping program using a SPECT dataset of patients with neurological disorders and normal control images.METHODS: Using statistical parametric mapping, 14 SPECT images from patients with various neurological disorders were compared individually with a databank of 32 normal images using a statistical threshold of p<0.05 (corrected for multiple comparisons at the level of individual voxels or clusters). Statistical parametric mapping results were compared with Visual analyses by a nuclear physician highly experienced in neurology (A) as well as a nuclear physician with a general background of experience (B) who independently classified images as normal or altered, and determined the location of changes and the severity.RESULTS: of the 32 images of the normal databank, 4 generated maps showing rCBF abnormalities (p<0.05, corrected). Among the 14 images from patients with neurological disorders, 13 showed rCBF alterations. Statistical parametric mapping and physician A completely agreed on 84.37% and 64.28% of cases from the normal databank and neurological disorders, respectively. The agreement between statistical parametric mapping and ratings of physician B were lower (71.18% and 35.71%, respectively).CONCLUSION: Statistical parametric mapping replicated the findings described by the more experienced nuclear physician. This finding suggests that automated methods for individually analyzing rCBF SPECT images may be a valuable resource to complement visual inspection in clinical practice.