Comet assay to evaluate chromosomal changes in chickens (Gallus gallus domesticus) contaminated by lead in a city in Bahia.

Chicken (Gallus gallus domesticus) is one of the primary sources of animal protein for the Brazilian population. Thus, the safety of this food is highly relevant. This study was based on the evidence of severe contamination of these animals by metals such as lead in Santo Amaro, Bahia. This exploratory study aimed to evaluate associations between lead levels in blood of chicken exposed to a contaminated area with the occurrence of chromosomal alterations, evidencing genotoxic effects. Serum lead analysis was performed by GF-AAS after dilution with a matrix modifier solution (Triton X-100 0.2% v/v and HNO3 0.1% v/v), while chromosomal damage was evaluated using the comet assay. The results showed genotoxic effects (positive comet assay) only for the specimen sample with higher serum lead concentrations (33.9 µg dL-1), suggesting the occurrence of toxic effects at this level of exposure. This work evaluated a relationship between the reduction of serum lead levels in chicken and increased distance from the primary polluting source - a lead processing plant (COBRAC). It also showed that lead is bioavailable in this territory, contaminating chicken and causing genotoxic effects in these animals, further expanding the concern with the local biota and the health of the residents of Santo Amaro.

Effects of altering the ratio of dietary n-6 to n-3 fatty acids on spontaneous luteolysis in lactating dairy cows.

Objectives were to evaluate the effects of altering the dietary ratio of omega-6 (n-6) to omega-3 (n-3) fatty acids on the profile of fatty acids and expression of genes related to the prostaglandin biosynthesis on endometrial tissue, uterine secretion of PGF2α, and timing of spontaneous luteolysis in dairy cows. Multiparous lactating Holstein cows (n = 45) were blocked based on milk yield and, within each block, assigned randomly to 1 of 3 dietary treatments at 14 d postpartum for 90 d. Diets were supplemented with a mixture of Ca salts of fish, safflower, and palm oils to create 3 different ratios of n-6 to n-3 fatty acids, namely R4, R5, and R6, which resulted in 3.9, 4.9, and 5.9 parts of n-6 to 1 part of n-3 fatty acids, respectively. Blood was sampled every 2 h from d 16 to 23 of the estrous cycle and assayed for concentrations of progesterone and the PGF2α metabolite 13,14-dihydro-15-keto-PGF2α (PGFM). In a subsequent estrous cycle, endometrial tissue was collected for biopsy on d 8 and endometrial fatty acids profile and gene expression were quantified. The proportion of arachidonic acid of the endometrial fatty acids increased as the dietary ratio n-6 to n-3 fatty acids increased (R4 = 9.05, R5 = 11.64, and R6 = 13.41%). On the other hand, proportions of eicosapentaenoic (R4 = 2.85, R5 = 2.14, and R6 = 2.02%) and docosahexaenoic (R4 = 3.30, R5 = 1.57, and R6 = 1.08%) decreased as the ratio of n-6 to n-3 fatty acids in the diet increased. Increasing the ratio of dietary n-6 to n-3 fatty acids increased mRNA expression of estrogen receptor 1, oxytocin receptor, cyclooxygenase 2, prostaglandin E and F synthases, and steroidogenic acute regulatory protein in endometrium, but decreased expression of peroxisome proliferator-activated receptor gamma and insulin-like growth factor-1. The changes in endometrium gene expression caused by dietary treatments were associated with changes in the ratio of n-6 to n-3 fatty acids in the endometrium. As the ratio increased from R4 to R6, the number of PGFM pulses (R4 = 5.6, R5 = 4.3, and R6 = 3.8 ± 0.6 pulses; least squares means ± standard error of the means) decreased, but the amplitude of the greatest PGFM pulse increased (R4 = 226, R5 = 267, and R6 = 369 ± 38 pg/mL). Luteolysis by d 23 of the estrous cycle was observed in 79.6% of the cows (R4 = 11/14; R5 = 13/15; and R6 = 11/15) and day of spontaneous luteolysis did not differ among treatments (R4 = 20.8; R5 = 21.1; and R6 = 21.0 ± 0.4). Three pulses of PGFM was the best predictor of luteolysis in dairy cows. Collectively, supplying the same quantity of fatty acids in the diet of lactating dairy cows, but altering the ratio of n-6 to n-3 fatty acids, influenced the endometrial fatty acids profile and gene expression and altered the pattern of prostaglandin synthesis; however, the changes were not sufficient to alter the length of the estrous cycle.

Selection of morphoagronomic descriptors for the characterization of accessions of cassava of the Eastern Brazilian Amazon.

The aim of this study was to select morphoagronomic descriptors to characterize cassava accessions representative of Eastern Brazilian Amazonia. It was characterized 262 accessions using 21 qualitative descriptors. The multiple-correspondence analysis (MCA) technique was applied using the criteria: contribution of the descriptor in the last factorial axis of analysis in successive cycles (SMCA); reverse order of the descriptor's contribution in the last factorial axis of analysis with all descriptors ('O'´p') of Jolliffe's method; mean of the contribution orders of the descriptor in the first three factorial axes in the analysis with all descriptors ('Os') together with ('O'´p'); and order of contribution of weighted mean in the first three factorial axes in the analysis of all descriptors ('Oz'). The dissimilarity coefficient was measured by the method of multicategorical variables. The correlation among the matrix generated with all descriptors and matrices based on each criteria varied (r = 0.21, r = 0.97, r = 0.98, r = 0.13 for SMCA, 'Os', 'Oz' and 'O'´p', respectively). The least informative descriptors were discarded independently and according to both 'Os' and 'Oz' criteria. Thirteen descriptors were capable to discriminate the accessions and to represent the morphological variability of accessions sampled in Brazilian Eastern Amazonia: color of apical leaves, petiole color, color of stem exterior, external color of storage root, color of stem cortex, color of root pulp, texture of root epidermis, color of leaf vein, color of stem epidermis, color of end branches of adult plant, branching habit, root shape, and constriction of root.

Effects of altering the ratio of dietary n-6 to n-3 fatty acids on performance and inflammatory responses to a lipopolysaccharide challenge in lactating Holstein cows.

The study was designed to evaluate the effects of altering the ratio between n-6 and n-3 fatty acids (FA) in the diet and the intake of these FA by lactating dairy cows on lactation performance and inflammatory acute phase responses to a challenge with lipopolysaccharide (LPS). Multiparous Holstein cows (n=45) were blocked based on milk yield from d 6 to d 10 postpartum and, within each block, assigned randomly to 1 of 3 dietary treatments at 14d postpartum; treatments lasted for 90d. Diets were supplemented with a mixture of Ca salts of fish, safflower, and palm oils to create 3 different ratios of n-6 to n-3 FA; namely, 3.9, 4.9, or 5.9 parts of n-6 to 1 part of n-3 FA (R4, R5, and R6, respectively). During the first 5 wk of the study, blood was sampled weekly and analyzed for concentrations of metabolites and hormones. On d 75 postpartum, cows received an infusion of 10µg of LPS into one quarter of the mammary gland to evaluate inflammatory acute phase responses. Altering the ratio of dietary n-6 to n-3 FA was reflected in changes in the FA composition of plasma and milk fat. Reducing the ratio of n-6 to n-3 FA from R6 to R4 increased dry matter intake (24.7, 24.6, and 26.1±0.5kg/d for R6, R5, and R4, respectively), with concurrent increases in yields of 3.5% fat-corrected milk (43.4, 45.4, and 48.0±0.8kg/d), milk fat (1.53, 1.60, and 1.71±0.03kg/d), milk true protein (1.24, 1.28, and 1.32±0.02kg/d), and milk lactose (2.12, 2.19, and 2.29±0.04kg/d). After the LPS challenge, concentrations of IL-6 in plasma increased as the ratio of n-6 to n-3 FA increased (112.5, 353.4, and 365.1±86.6pg/mL for R4, R5, and R6, respectively). Elevations of body temperature and somatic cell count were greater for cows fed R5 compared with those fed R4 or R6 (41.3, 40.8, and 40.8±0.2°C; 4.33, 3.68, and 3.58±0.25×10(6)/mL, for R5, R4, and R6, respectively). Haptoglobin concentration was greatest at 24h after LPS challenge for cows fed R6. Phagocytosis and oxidative burst by neutrophils collected from circulation were unaffected by dietary treatment in the first 48h after intramammary LPS infusion. In conclusion, supplying the same quantity of FA in the diet of early lactation dairy cows but altering the ratio of the polyunsaturated FA of the n-6 to n-3 families influenced lactation performance and inflammatory responses to an LPS challenge.

The role played by endogenous and exogenous electric fields in DNA signaling and repair

Comments are made and new insights are provided on the key role played by endogenous and exogenouselectric fields, where the former starts and conducts the repairing chain, while the latter is able to scramblethe completion of the repair process and, as a consequence, may have important potential as a radiationsensitizer for clinical application.

Osteomalacia secondary to renal tubular acidosis in a patient with primary Sjögren's syndrome.

We report a case of a 41-year-old woman whose disease manifested as osteomalacia and whose etiological investigation revealed renal tubular acidosis secondary to primary Sjögren's syndrome. Proximal tubular dysfunction was also present and was documented by increased urinary excretion of beta-2-microglobulin and retinol-binding protein. The patient showed clinical and laboratory improvement after treatment with oral potassium citrate, calcium supplements and steroids.

Lymphocyte proliferation and sister chromatid exchange in Alzheimer's disease.

Sister chromatid exchange (SCE) and lymphocyte proliferation were studied in peripheral lymphocyte cultures derived from 5 patients with Alzheimer disease (AD), 5 control elderly subjects and 5 young donors. These parameters did not differ significantly between the AD group and the elderly control group, but higher SCE frequency and less intensive proliferation were observed in the AD group and in the elderly control group when compared to the young donors.

Renal disease in the elderly: etiology and evolution of 24 cases

We retrospectively analyzed the histological data, clinical presentations, and outcome of 24 patients aged 60 years or older at the initial evaluation for renal disease. The study setting was a referral-based nephrology clinic at a tertiary care center. Twenty-three out of the 24 patients had a mean follow-up of 16 months (range 3-48). Their mean age was 65 years (range 60-75). The most common histological diagnoses were crescentic glomerulonephritis (GN) (n = 4), membranoproliferative GN (n = 4), diffuse endocapillary proliferative GN (n = 3), and minimal change (n = 3). Clinical presentation included renal insufficiency in 16 patients, the nephrotic syndrome in 8 patients (associated in 4 with decreased renal function), and hematuria with subnephrotic rang proteinuria in 4 cases. Ten out of the 23 patients developed end-stage renal disease (ESRD). Median serum creatinine at presentation in the group that developed ESRD was significantly higher than in the group that did not develop ESRD (490 vs 270 mumol/l; p < 0.05). Seven patients died, 5 of whom had developed ESRD. A variety of renal diseases affect the kidneys of the elderly; prognosis was unfavorable in about half of the patients in this series. Larger prospective studies are needed to clarify the natural history of GN in the elderly.

[Blood glucose level in hepato-intestinal schistosomiasis]. / Curva glicêmica na esquistossomose hépato-iontestinal.

Comparative oral glucose tolerance test performed in 30 patients with hepato-intestinal schistosomiasis and 30 controls, showed that the mean value of glycemia in the former group was superior. However, none of these patients show a diabetic G.T.T. curve.

Curva glicemica na esquistossomose hepato-intestinal. / Glucose level in hepatointestinal schistosomiasis

Os autores apresentam o resultado do teste de tolerancia a glicose via oral em 30 pacientes com esquistossomose hepato-intestinal e 30 controles. O estudo mostrou que a glicemia media foi superior nos esquistossomoticos, nos diferentes tempos do exame. Nenhum paciente com curva diabetica. Em todos os pacientes o teste foi normal. A diferenca dos valores so foi estatisticamente significante na glicemia de jejum