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.

Blood galactose and glucose levels in mothers, cord blood, and 48-hour-old breast-fed full-term infants

Background: Although galactose is an important component in human lactose, there are few reports of its role in the newborn metabolism. Objective: To determine the relationship of blood galactose and glucose levels in mothers, cord blood, and breast-fed full-term newborn infants. Methods: Maternal and cord vein blood samples were obtained from 27 pregnant women at delivery, and from their breastfed, full-term newborns 48 h later. Galactose and glucose were determined by HPLC. Statistical analysis used ANOVA and Pearson correlation with p < 0.05. Results: Maternal galactose concentrations (0.08 +/- 0.03 mmol/l) were similar to cord blood galactose (0.07 +/- 0.03 mmol/l; p = 0.129). However, newborn blood galactose (0.05 +/- 0.02 mmol/l) was significantly lower than both cord (p = 0.042) and maternal blood (p = 0.002). Maternal blood glucose levels (4.72 +/- 0.86 mmol/l) were higher than cord blood (3.98 +/- 0.57 mmol/l; p < 0.001), and cord blood concentrations were higher than newborn blood levels (3.00 +/- 0.56 mmol/l; p < 0.001); all values expressed as mean +/- SD. Significant correlation was only seen between maternal and cord blood galactose levels (r = 0.67; p < 0.001) and glucose levels (r = 0.38; p = 0.047). Conclusion: the association and similarity between maternal and cord blood galactose levels suggest that the fetus is dependent on maternal galactose. In contrast, the lower galactose levels in newborn infants and a lack of association between both suggest self-regulation and a dependence on galactose ingestion. Copyright (c) 2007 S. Karger AG, Basel.

Effect of intravenous propofol and remifentanil on heart rate, blood pressure and nociceptive response in acepromazine premedicated dogs

ObjectiveTo investigate the cardiorespiratory, nociceptive and endocrine effects of the combination of propofol and remifentanil, in dogs sedated with acepromazine.Study designProspective randomized, blinded, cross-over experimental trial.AnimalsTwelve healthy adult female cross-breed dogs, mean weight 18.4 +/- 2.3 kg.MethodsDogs were sedated with intravenous (IV) acepromazine (0.05 mg kg-1) followed by induction of anesthesia with IV propofol (5 mg kg-1). Anesthesia was maintained with IV propofol (0.2 mg kg-1 minute-1) and remifentanil, infused as follows: R1, 0.125 mu g kg-1 minute-1; R2, 0.25 mu g kg-1 minute-1; and R3, 0.5 mu g kg-1 minute-1. The same dogs were administered each dose of remifentanil at 1-week intervals. Heart rate (HR), mean arterial pressure (MAP), respiratory rate (f(R)), end tidal CO(2) (Pe'CO(2)), arterial hemoglobin O(2) saturation, blood gases, and rectal temperature were measured before induction, and 5, 15, 30, 45, 60, 75, 90, and 120 minutes after beginning the infusion. Nociceptive response was investigated by electrical stimulus (50 V, 5 Hz and 10 ms). Blood samples were collected for plasma cortisol measurements. Statistical analysis was performed by anova (p < 0.05).ResultsIn all treatments, HR decreased during anesthesia with increasing doses of remifentanil, and increased significantly immediately after the end of infusion. MAP remained stable during anesthesia (72-98 mmHg). Antinociception was proportional to the remifentanil infusion dose, and was considered satisfactory only with R2 and R3. Plasma cortisol concentration decreased during anesthesia in all treatments. Recovery was smooth and fast in all dogs.Conclusions and clinical relevanceInfusion of 0.25-0.5 mu g kg-1 minute-1 remifentanil combined with 0.2 mg kg-1 minute-1 propofol produced little effect on arterial blood pressure and led to a good recovery. The analgesia produced was sufficient to control the nociceptive response applied by electrical stimulation, suggesting that it may be appropriate for performing surgery.

Leishmune (R) vaccine blocks the transmission of canine visceral leishmaniasis - Absence of Leishmania parasites in blood, skin and lymph nodes of vaccinated exposed dogs

Leishmune (R) vaccine is the first licensed vaccine against canine visceral leishmaniasis. It contains the Fucose-Mannose-ligand (FML) antigen of Leishmania donovani. The potential Leishmune (R) vaccine effect on the interruption of the transmission of the disease, was assayed by monitoring, in untreated (n = 40) and vaccinated dogs (n = 32) of a Brazilian epidemic area: the kala-azar clinical signs, the FML-seropositivity and the Leishmania parasite evidence by immunohistochemistry of skin and PCR for Leishmanial DNA of lymph node and blood samples. on month I I after vaccination, untreated controls showed: 25% of symptomatic cases, 50% of FML-seropositivity, 56.7% of lymph node PCR, 15.7% of blood PCR and 25% of immunohistochemical positive reactions. The Leishmune (R)-vaccinated dogs showed 100% of seropositivity to FML and a complete absence of clinical signs and of parasites (0%) in skin, lymph node and blood PCR samples (P < 0.01). The positivity in FML-ELISA in untreated dogs significantly correlates with the PCR in lymph node samples (p < 0.001) and with the increase in number of symptoms (p = 0.006) being strong markers of infectiousness. The absence of symptoms and of evidence of Leishmania DNA and parasites in Leishmune (R)-vaccinated animals indicates the non-infectious condition of the Leishmune (R)-vaccinated dogs. (c) 2005 Elsevier Ltd. All rights reserved.

Effects of aerobic exercise on the blood pressure, oxidative stress and eNOS gene polymorphism in pre-hypertensive older people

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

Lack of association between ABO histo-blood groups, secretor and non-secretor phenotypes, and anti-Toxoplasma gondii antibodies among pregnant women from the northwestern region of São Paulo State, Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Morphological, morphometrical and ultrastructural characterization of Phrynops geoffroanus' (Testudines: Chelidae) blood cells, in different environments

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Silver as internal standard for simultaneous determination of Cd and Pb in whole blood by electrothermal atomic absorption spectrometry

The use of internal standardization for simultaneous atomic absorption spectrometry (SIMAAS) was investigated for Cd and Pb determination in whole blood. The comparison of thermochemical and physicochemical parameters allowed the selection of Ag, Bi, and Tl as internal standard candidates. Correlation graphs, plotted from the normalized absorbance signals (n = 20) of internal standard (axis y) versus analyte ( axis x), precision and accuracy were used to select Ag as the most appropriate internal standard. Blood samples were diluted (1 + 9) with 0.11% (m/v) Triton X-100 + 1.1% (v/v) HNO3 + 0.28% (m/v) NH4H2PO4 + 10 mug L-1 Ag+. Pyrolysis and atomization temperatures for the optimized heating program were 550 and 1700 degreesC, respectively. Characteristic masses based on integrated absorbance were 1.68 +/- 0.01 pg for Cd and 30.3 +/- 0.1 pg for Pb. The detection limits (DL) were 0.095 +/- 0.001 mug L-1 and 0.86 +/- 0.01 mug L-1 for Cd and Pb, respectively. The mean RSD for all determinations was the same for Cd (13 +/- 9%) with or without Ag as internal standard ( IS). on the other hand, the use of Ag as IS improved the RSD for Pb from 3.6 +/- 4.0% to 2.2 +/- 2.0%. An effective contribution of the internal standard Ag was verified in the recoveries of spiked samples (0.5 mug L-1 Cd2+ and 5.0 mug L-1 Pb2+). The mean recoveries were 81 +/- 8% and 91 +/- 4% for Cd, and 80 +/- 11% and 93 +/- 6% for Pb without and with IS correction, respectively. This is the first application of IS for a simultaneous determination by SIMAAS.

Effect of exercise mode on the blood lactate removal during recovery of high-intensity exercise

The aim of this study was to determine the effect of exercise mode on the blood lactate removal during recovery of high-intensity exercise. Nine male individuals performed the following tests in order to determine the blood lactate removal: Running - 2x200 m, the subjects ran at their maximum capacity, and rested 2 min between each bout. Swimming - 2x50 m, the subjects swam at their maximum capacity, and rested 2 min between each bout. Each test was realized on different days with three recovery modes: passive (sitting down), swimming, or running. Recovery exercise intensity was corresponding to the aerobic threshold. All recovery activities lasted 30 min. The two forms of active recovery were initiated 2 min after the end of high-intensity exercise and lasted 15 min, and were followed by 13 min of seated rest. After 1,7, 12,17, and 30 min of the end of high-intensity exercise, blood samples (25 mu l) were collected in order to determine the blood lactate concentration. By linear regression, between the logarithm of lactate concentration and its respective time of recovery, the half-time of blood lactate removal (t1/2) was determined. Time of high-intensity exercise and the lactate concentration obtained in the 1(st) min of recovery were not different between running and swimming. Passive recovery (PR) following running (R-PR=25.5+/-4.3 min) showed a t1/2 significantly higher than PR after swimming (S-PR=18.6+/-4.3 min). The t1/2 of the sequences running-running (R-R=13.0 min), running-swimming (R-S=12.9+/-3.8 min), swimming-swimming (S-S=13.2+/-2.8 min), and swimming-running (S-R=12.9+/-3.8 min) were significantly lower than the t1/2 of the R-PR and S-PR. There was no difference between the t1/2 of the sequences R-R R-S, and S-S. on the other hand the sequence S-R showed a t1/2 significantly lower than the sequences S-S and R-R. It was concluded that the two forms of active recovery determine an increase in the blood lactate removal, regardless of the mode of high-intensity exercise performed previously. Active recovery performed by the muscle groups that were not previously fatigued, can improve the blood lactate removal.

The effects of ice-water storage on blood gas and acid-base measurements

Objective: To determine the effects of storage of arterial and venous blood samples in ice water on blood gas and acid-base measurements.Design: Prospective, in vitro, laboratory study.Setting: School of veterinary medicine.Subjects: Six healthy dogs.Measurements and main results: Baseline measurements of partial pressure of oxygen (PO2), partial pressure of carbon dioxide (PCO2), pH, hemoglobin concentration (tHb), oxyhemoglobin saturation, and oxygen content (ContO(2)) were made. Bicarbonate (HCO3) and standard base excess (SBE) were calculated. Arterial and venous blood samples were separated into 1 and 3 mL samples, anaerobically transferred into 3 mL plastic syringes, and stored in ice water for 6 hours. Measurements were repeated at 15, 30 minutes, and 1, 2, 4, and 6 hours after baseline measurements. Arterial (a) PO2 increased significantly from baseline after 30 minutes of storage in the 1 mL samples and after 2 hours in the 3 mL samples. Venous (v) PO2 was significantly increased from baseline after 4 hours in the 1 mL samples and after 6 hours in the 3 mL samples. The pHa significantly decreased after 2 hours of storage in the 1 mL samples and after 4 hours in the 3 mL samples. In both the 1 and 3 mL samples, pHv decreased significantly only after 6 hours. Neither the arterial nor the venous PCO2 values changed significantly in the 1 mL samples and increased only after 6 hours in the 3 mL samples. No significant changes in tHb, ContO(2), SBE, or HCO3 were detected.Conclusions: the PO2 of arterial and venous blood increased significantly when samples were stored in plastic syringes in ice water. These increases are attributable to the diffusion of oxygen from and through the plastic of the syringe into the blood, which occurred at a rate that exceeded metabolic consumption of oxygen by the nucleated cells.

A Simple Method Based on ICP-MS for Estimation of Background Levels of Arsenic, Cadmium, Copper, Manganese, Nickel, Lead, and Selenium in Blood of the Brazilian Population

Throughout the world, biomonitoring has become the standard for assessing exposure of individuals to toxic elements as well as for responding to serious environmental public health problems. However, extensive biomonitoring surveys require rapid and simple analytical methods. Thus, a simple and high-throughput method is proposed for the determination of arsenic (As), cadmium (Cd), copper (Cu), manganese (Mn), nickel (Ni), lead (Pb), and selenium (Se) in blood samples by using inductively coupled plasma-mass spectrometry (ICP-MS). Prior to analysis, 200 l of blood samples was mixed with 500 l of 10% v/v tetramethylammonium hydroxide (TMAH) solution, incubated for 10 min, and subsequently diluted to 10 ml with a solution containing 0.05% w/v ethylenediamine tetraacetic acid (EDTA) + 0.005% v/v Triton X-100. After that, samples were directly analyzed by ICP-MS (ELAN DRC II). Rhodium was selected as an internal standard with matrix-matching calibration. Method detection limits were 0.08, 0.04, 0.5, 0.09, 0.12, 0.04, and 0.1 g//L for As, Cd, Cu, Mn, Ni, Pb, and Se, respectively. Validation data are provided based on the analysis of blood samples from the trace elements inter-\comparison program operated by the Institut National de Sante Publique du Quebec, Canada. Additional validation was provided by the analysis of human blood samples by the proposed method and by using electrothermal atomic absorption spectrometry (ETAAS). The method was subsequently applied for the estimation of background metal blood values in the Brazilian population. In general, the mean concentrations of As, Cd, Cu, Mn, Ni, Pb, and Se in blood were 1.1, 0.4, 890, 9.6, 2.1, 65.4, and 89.3 g/L, respectively, and are in agreement with other global populations. Influences of age, gender, smoking habits, alcohol consumption, and geographical variation on the values were also considered. Smoking habits influenced the levels of Cd in blood. The levels of Cu, Mn, and Pb were significantly correlated with gender, whereas Cu and Pb were significantly correlated with age. There were also interesting differences in Mn and Se levels in the population living in the north of Brazil compared to the south.

The carpal pad as an alternative sampling site for blood glucose testing in dogs

To investigate the feasibility and validity of sampling blood from the carpal pad in hospitalised healthy and diabetic dogs. METHODS The carpal pad was compared to the ear as a sampling site in 60 dogs (30 healthy and 30 diabetic dogs). RESULTS Lancing the pads was very well tolerated. The average glucose concentrations in blood samples obtained from the ears and carpal pads exhibited a strong positive correlation (r = 0.938) and there were no significant differences between them (P = 0.914). In addition, 98.3% of the values obtained were clinically acceptable when assessed by the error grid analysis. CLINICAL SIGNIFICANCE The carpal pad is a good alternative sampling site for home monitoring, especially in animals with a soft and/or light-coloured pad.

Minimum blood lactate and muscle protein of rats during swimming exercise

Few studies dealing with effort intensity during swimming exercise in rats have been reported in the literature. Recently, with the use of the lactate minimum test (LMT), our group estimated the minimum blood lactate (MBL) of rats during swimming exercises. This information allowed accurate evaluation of the effort intensity developed by rats during swimming exercise. The present study was designed to evaluate the effects of swimming exercise sessions in below, equivalent and above intensities to MBL, on protein metabolism of rats. Adult (90 days) sedentary male Wistar rats were used in the present study. Mean values of MBL, in the present study, were obtained at blood concentration of 6.7 +/- 0.4 mmol/L with a load of 5% bw. The animals were sacrificed at rest (R) or immediately after a single swimming session (30 min) supporting loads below (3.5% bw), equivalent (5.0% bw) and high load (6.5% bw) to AT. Blood samples were collected each 5 min of exercise for lactate determination. Soleus muscle protein synthesis (amount of L-[C-14] fenil alanyn incorporation to protein) and breakdown (tyrosin release) rates were evaluated. Blood lactate concentrations (mmol/L) stabilized with the below (5.4 +/- 0.01) and equivalent (6.4 +/- 0.006) to MBL but increased, progressively, with the high load. There were no differences in protein synthesis (pmol/mg.h) among rest values (65.2 +/- 3.4) and after-exercise supporting the loads below (61.5 +/- 1.3) and the equivalent (60.7+/-1.7) to MBL but there was a decrease with the high load (36.6+/-2.0). Protein breakdown rates (pmol/g.h) increase after exercise supporting the loads below (227.0 +/- 6.1), equivalent (227.9 +/- 6.0) and high (363.6 +/- 7.1) to MBL in relation to the rest (214.3 +/- 6.0). The results indicate the viability of the application of LMT in studies with rats since it detected alterations imposed by exercise.

Comparison of oxidative stress and the frequency of polymorphisms in the HFE gene between hemoglobin S trait blood donors and sickle cell disease patients

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Pyrethroid residues in milk and blood of dairy cows following single topical applications

The presence of the pyrethroid insecticides flumethrin, deltamethrin, cypermethrin and cyhalothrin in milk and blood of 10 cows was determined after single dermal applications of recommended doses. Milk and blood samples were collected every 7 days over a 35 d period and analyzed by high performance liquid chromatography. The highest residues in milk were found on day 28 for flumethrin and day 1 for deltamethrin, cypermethrin and cyhalothrin, while in blood the highest concentrations were present on day 28 for flumethrin and deltamethrin, the first day for cypermethrin, and day 14 for cyhalothrin.