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BACKGROUND: The Brazilian Cohort of Asthma São Paulo (BRASASP) had a well-characterized severe asthmatic in Brazil, with 12 years of follow-up under standard treatment. METHODS: Sequential assessment of patients with uncontrolled asthma from BRASASP cohort was carried out with 12 years of follow-up, performing exams and comparing with previous measurements. RESULTS: 50 from the 60 initial patients were reevaluated. Twelve years later, FEV1 and the FEV1/FVC ratio have significantly decreased, with a rate of loss of lung function of 11.8 and 14%, respectively, and worsening in small airway parameters such as RV/TLC. BMI, The Asthma Control Test (ACT) and Asthma Control Questionnaire (ACQ) scores haven't changed. However, exacerbations decreased by 56%. Mean daily inhaled corticosteroid use was similar over time, but daily oral corticosteroid use decreased, in addition to a significant reduction in induced sputum eosinophilic and neutrophilic profile and serum IgE. Rhinitis, sinusitis, and GERD were the main comorbidities. In quality of life according to respiratory questionnaire SGRQ, total score showed a huge improvement (62% of patients). CONCLUSIONS: There was significant decrease in FEV1 and FEV1/FVC. Data of pulmonary functional small airway characteristics show globally affected airways. Although higher doses of medications, patients were still uncontrolled, but with reduction of exacerbations, daily use of oral corticosteroid, less eosinophils and neutrophils in induced sputum and lower levels of IgE. Improvement in quality of life in 62% of patients.

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Brazil nut tree (Bertholletia excelsa) is native of the Amazon rainforest. Brazil nuts are consumed worldwide and are known as the richest food source of selenium (Se). Yet, the reasoning for such Se contents is not well stablished. We evaluated the variation in Se concentration of Brazil nuts from Brazilian Amazon basin, as well as soil properties, including total Se concentration, of the soils sampled directly underneath the trees crown, aiming to investigate which soil properties influence Se accumulation in the nuts. The median Se concentration in Brazil nuts varied from 2.07 mg kg-1 (in Mato Grosso state) to 68.15 mg kg-1 (in Amazonas state). Therefore, depending on its origin, a single Brazil nut could provide from 11% (in the Mato Grosso state) up to 288% (in the Amazonas state) of the daily Se requirement for an adult man (70 µg). The total Se concentration in the soil also varied considerably, ranging from <65.76 to 625.91 µg kg-1, with highest Se concentrations being observed in soil samples from the state of Amazonas. Se accumulation in Brazil nuts generally increased in soils with higher total Se content, but decreased under acidic conditions in the soil. This indicates that, besides total soil Se concentration, soil acidity plays a major role in Se uptake by Brazil nut trees, possibly due to the importance of this soil property to Se retention in the soil.

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This study aimed to examine the time course of endothelial function after a single handgrip exercise session combined with blood flow restriction in healthy young men. Nine participants (28 ± 5.8 years) completed a single session of bilateral dynamic handgrip exercise (20 min with 60% of the maximum voluntary contraction). To induce blood flow restriction, a cuff was placed 2 cm below the antecubital fossa in the experimental arm. This cuff was inflated to 80 mmHg before initiation of exercise and maintained through the duration of the protocol. The experimental arm and control arm were randomly selected for all subjects. Brachial artery flow-mediated dilation (FMD) and blood flow velocity profiles were assessed using Doppler ultrasonography before initiation of the exercise, and at 15 and 60 min after its cessation. Blood flow velocity profiles were also assessed during exercise. There was a significant increase in FMD 15 min after exercise in the control arm compared with before exercise (64.09% ± 16.59%, P=0.001), but there was no change in the experimental arm (-12.48% ± 12.64%, P=0.252). FMD values at 15 min post-exercise were significantly higher for the control arm in comparison to the experimental arm (P=0.004). FMD returned to near baseline values at 60 min after exercise, with no significant difference between arms (P=0.424). A single handgrip exercise bout provoked an acute increase in FMD 15 min after exercise, returning to near baseline values at 60 min. This response was blunted by the addition of an inflated pneumatic cuff to the exercising arm.

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This study aimed to examine the time course of endothelial function after a single handgrip exercise session combined with blood flow restriction in healthy young men. Nine participants (28±5.8 years) completed a single session of bilateral dynamic handgrip exercise (20 min with 60% of the maximum voluntary contraction). To induce blood flow restriction, a cuff was placed 2 cm below the antecubital fossa in the experimental arm. This cuff was inflated to 80 mmHg before initiation of exercise and maintained through the duration of the protocol. The experimental arm and control arm were randomly selected for all subjects. Brachial artery flow-mediated dilation (FMD) and blood flow velocity profiles were assessed using Doppler ultrasonography before initiation of the exercise, and at 15 and 60 min after its cessation. Blood flow velocity profiles were also assessed during exercise. There was a significant increase in FMD 15 min after exercise in the control arm compared with before exercise (64.09%±16.59%, P=0.001), but there was no change in the experimental arm (-12.48%±12.64%, P=0.252). FMD values at 15 min post-exercise were significantly higher for the control arm in comparison to the experimental arm (P=0.004). FMD returned to near baseline values at 60 min after exercise, with no significant difference between arms (P=0.424). A single handgrip exercise bout provoked an acute increase in FMD 15 min after exercise, returning to near baseline values at 60 min. This response was blunted by the addition of an inflated pneumatic cuff to the exercising arm.

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Sarcopenic obesity is the combination of reduced fat-free mass (FFM) and increased fat mass (FM) with advancing age but there is lack of clear criteria for its identification. The purposes of the present investigation were: 1) to determine the prevalence of postmenopausal women with reduced FFM relative to their FM and height, and 2) to examine whether there are associations between the proposed classification and health-related variables. A total of 607 women were included in this cross-sectional study and were separated into two subsets: 258 older women with a mean age of 66.8 ± 5.6 years and 349 young women aged 18-40 years (mean age, 29.0 ± 7.5 years). All volunteers underwent body composition assessment by dual-energy X-ray absorptiometry. The FFM index relative to FM and height was calculated and the cutoff value corresponded to two standard deviations below the mean of the young reference group. To examine the clinical significance of the classification, all older participants underwent measurements of quadriceps strength and cardiorespiratory fitness. Values were compared between those who were classified as low FFM or not, using an independent samples t-test and correlations were examined. The cutoff corresponded to a residual of -3.4 and generated a sarcopenic obesity prevalence of 19.8 percent that was associated with reduced muscle strength and aerobic fitness among the older participants. Also, the index correlated significantly with the health-related fitness variables. The results demonstrated reduced functional capacity for those below the proposed cutoff and suggested applicability of the approach as a definition for sarcopenic obesity.

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Sarcopenic obesity is the combination of reduced fat-free mass (FFM) and increased fat mass (FM) with advancing age but there is lack of clear criteria for its identification. The purposes of the present investigation were: 1) to determine the prevalence of postmenopausal women with reduced FFM relative to their FM and height, and 2) to examine whether there are associations between the proposed classification and health-related variables. A total of 607 women were included in this cross-sectional study and were separated into two subsets: 258 older women with a mean age of 66.8 ± 5.6 years and 349 young women aged 18-40 years (mean age, 29.0 ± 7.5 years). All volunteers underwent body composition assessment by dual-energy X-ray absorptiometry. The FFM index relative to FM and height was calculated and the cutoff value corresponded to two standard deviations below the mean of the young reference group. To examine the clinical significance of the classification, all older participants underwent measurements of quadriceps strength and cardiorespiratory fitness. Values were compared between those who were classified as low FFM or not, using an independent samples t-test and correlations were examined. The cutoff corresponded to a residual of -3.4 and generated a sarcopenic obesity prevalence of 19.8% that was associated with reduced muscle strength and aerobic fitness among the older participants. Also, the index correlated significantly with the health-related fitness variables. The results demonstrated reduced functional capacity for those below the proposed cutoff and suggested applicability of the approach as a definition for sarcopenic obesity.

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This study examined the association between ACE I/D and ACTN3 R577X polymorphisms and muscle-related phenotypes and their adaptation to resistance training in older women. Volunteers (n=246;age=66.7 ± 5.5 years) underwent quadriceps strength assessment using isokinetics and fat-free mass by dual energy X-ray absorptiometry. 79 volunteers performed 24 weeks of resistance training and 75 were studied as controls. Genotypes were identified by standard procedures. No associations were observed for muscle strength for either gene, but volunteers carrying the D/D genotype presented higher appendicular fat-free mass compared to the I-allele carriers (6.3 ± 0.1 vs. 6.1 ± 0.1 kg/m (2)). The X-allele carriers presented higher relative fat-free mass when compared to homozygous R/R (16.3 ± 0.1 vs. 15.9 ± 0.1 kg/m (2)). All fat-free mass variables were significantly greater for carriers of both X/X and D/D genotypes. In response to RT, only the I-allele carriers significantly increased fat-free mass and a significant training × genotype interaction was noted. These findings do not support a pivotal role for the studied polymorphisms in determining muscle strength in older women, but suggest a modest role in fat-free mass determination. Of note, the results provide a novel insight that these genetic variations may interact to determine muscle mass in older women.

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Manganese removal from mining-affected waters is an important challenge for the mining industry. Addressed herein is this issue in both batch and continuous conditions. Batch experiments were carried out with synthetic solutions, at 23+/-2 degrees C, initial pH 5.5 and 8.3 g limestone/L. Similarly, continuous tests were performed with a 16.5 mg/L Mn(2+) mine water, at 23 degrees C, initial pH 8.0 and 20.8 g limestone/L. Calcite limestone gave the best results and its fine grinding proved to the most effective parameter for manganese removal. In either synthetic solutions or industrial effluents, the final manganese concentration was below 1 mg/L. A change in limestone surface zeta potential is observed after manganese removal and manganese carbonate formation was suggested by IR spectroscopy. The conclusion is that limestone can remove manganese from industrial effluents for values that comply with environmental regulations.

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The exposure to benzene is a public health problem. Although the most well-known effect of benzene is hematopoietic toxicity, there is little information about the benzene and its metabolites effects on the central nervous system (CNS). This study examined the toxic effects of 1,2-dihydroxybenzene (catechol), a benzene metabolite, to human glioblastoma GL-15 cells. GL-15 cell cultures were used as a model to provide more information about the toxic effects of aromatic compounds to the CNS. Catechol induced time- and concentration-dependent cytotoxic effects. Morphological changes, such as the retraction of the cytoplasm and chromatin clumping, were seen in cells exposed to 200 microM catechol for 48 hours. In cells exposed to 600 microM catechol for 48 hours, 78.0% of them presented condensed nuclei, and the Comet assay showed DNA damage. The percentage of cells labeled with annexin V (apoptotic cells) was greater in the group exposed to catechol (20.7%) than in control cells (0.4%). Exposure to catechol at concentrations greater than 100 microM enhanced Bax levels, and a decrease in Bcl-2 level was observed after the exposure to 600 microM catechol for 48 hours. Furthermore, catechol depleted reduced glutathione. Hence, catechol induced cell death mainly by apoptosis.

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The present study investigated the interaction between Cdx-2 polymorphism and physical activity level over bone mineral density (BMD) variation in Brazilian postmenopausal women. One hundred and ninety women volunteered to participate in the study (66.6 +/- 5.3 years, 64.58 +/- 11.74 kg and 151.94 +/- 6.36 cm). Physical activity level (PAL) was assessed using the international physical activity questionnaire (IPAQ). Lumbar spine (L2 - L4), femoral neck, great trochanter and Wards' triangle bone mineral density (BMD) were measured by dual-energy X-ray absorptiometry (DXA). The Cdx-2 polymorphism was genotyped by minisequencing, using the SNaPshottrade mark Multiplex System (Applied Biosystems, Foster City, CA, USA). Overall, no significant association was found between Cdx-2 polymorphism and adjusted BMD at any site. However, the results revealed a significant interaction between PAL and Cdx-2 genotype on adjusted femoral neck and Wards' triangle BMD. Active women carrying the Cdx-G/G genotype showed higher adjusted femoral neck and Wards' triangle BMD than inactive women carrying the same genotype, thus suggesting a larger chronic response to physical activity. These results suggest that, in postmenopausal women, the Cdx-2 polymorphism does not influence BMD by itself; however, it seems to affect the BMD response to physical activity since only the Cdx-G/G genotype carriers presented significant differences between active and inactive.

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The well-described role of the vitamin D endocrine system in bone metabolism makes its receptor a widely investigated candidate gene in association studies looking for the genetic basis of complex bone-related phenotypes. Most association studies genotype five polymorphic sites along the gene using PCR-RFLP and allele-specific amplification methods, which may not be the better choice in large case/control or cross-sectional studies. In this case, genotyping SNPs in parallel and using automated allele-calling methods are important to decrease genotyping errors due to manual data handling and save sample in cases where the amount of DNA is limited. The aim of this study was to present a straightforward method based on multiplex PCR amplification followed by multiplex single-base extension as a simple way to genotype five vitamin D receptor gene polymorphisms in parallel, which may be implemented in medium- to large-scale case/control or cross-sectional studies. The results regarding method feasibility and optimization are presented by genotyping eight paternity trios and seven samples of Brazilian postmenopausal women who took part in an ongoing association study carried out by members of our group.

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The well-described role of the vitamin D endocrine system in bone metabolism makes its receptor a widely investigated candidate gene in association studies looking for the genetic basis of complex bone-related phenotypes. Most association studies genotype five polymorphic sites along the gene using PCR-RFLP and allele-specific amplification methods, which may not be the better choice in large case/control or cross-sectional studies. In this case, genotyping SNPs in parallel and using automated allele-calling methods are important to decrease genotyping errors due to manual data handling and save sample in cases where the amount of DNA is limited. The aim of this study was to present a straightforward method based on multiplex PCR amplification followed by multiplex single-base extension as a simple way to genotype five vitamin D receptor gene polymorphisms in parallel, which may be implemented in medium- to large-scale case/control or cross-sectional studies. The results regarding method feasibility and optimization are presented by genotyping eight paternity trios and seven samples of Brazilian postmenopausal women who took part in an ongoing association study carried out by members of our group.

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Proteinase activities in the larval midguts of the bruchids Callosobruchus maculatus and Zabrotes subfasciatus were investigated. Both midgut homogenates showed a slightly acidic to neutral pH optima for the hydrolysis of fluorogenic substrates. Proteolysis of epsilon-aminocaproil-Leu-Cys(SBzl)-MCA was totally inhibited by the cysteine proteinase inhibitors E-64 and leupeptin, and was activated by 1.5 mM DTT in both insects, while hydrolysis of the substrate Z-ArgArg-MCA was inhibited by aprotinin and E-64, which suggests that it is being hydrolysed by serine and cysteine proteinases. Gel assays showed that the proteolytic activity in larval midgut of C. maculatus was due to five major cysteine proteinases. However, based on the pattern of E-64 and aprotinin inhibition, proteolytic activity in larval midgut of Z. subfasciatus was not due only to cysteine proteinases. Fractionation of the larval midgut homogenates of both bruchids through ion-exchange chromatography (DEAE-Sepharose) revealed two peaks of activity against Z-ArgArg-MCA for both bruchid species. The fractions from C. maculatus have characteristics of cysteine proteinases, while Z. subfasciatus has one non-retained peak of activity containing cysteine proteinases and another eluted in a gradient of 250-350 mM NaCl. The proteolytic activity of the retained peak is higher at pH 8.8 than at pH 6.0 and corresponds with a single peak that is active against N-p-tosyl-GlyGlyArg-MCA, and sensitive to 250 microM aprotinin (90% inhibition). The peak contains a serine proteinase which hydrolyzes alpha-amylase inhibitor 1 from the common bean (Phaseolus vulgaris). Arch.

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Informaçöes sobre peso à desmama de bezerros Nelore foram utilizadas após ajuste para idade padräo aos 205 dias, sexo, idade da mäe, touro e mês de desmama, para separar as reprodutrizes em dois grupos, segundo o peso de suas crias. As médias de peso dos bezerros ajustadas pelo método dos quadrados mínimos e erros-padräo (LSMñSE) foram para os grupos pesados (P) e leves (L) 163,21ñ2,18kg e 134,44ñ2,18kg, respectivamente, com 41 animais em cada grupo. Essas reprodutrizes foram submetidas a coleta de sangue para estudo de polimorfismos do gene da ß-lactoglobulina, por meio da técnica de PCR-RFLP. A amplificaçäo e a digestäo de um fragmento do gene da ß-lactoglobulina entre o éxon II e III identificou os genótipos 1AA, 24AB e 56BB, com as freqüências de 0,16 e 0,84 para os alelos. A e B, respectivamente. Os 24 animais com genótipo AB apresentaram LSMñSE de peso de seus produtos de 149,50ñ4,17kg, e os 56 animais de genótipo BB tiveram média de 148,44ñ2,73kg. O teste do quiquadrado näo apresentou significância (P>0,05), isto é, os grupos P e L näo diferiram entre si quanto às freqüências alélicas apresentadas para esse gene. O genótipo das reprodutrizes näo afetou o peso à desmama de suas crias, o que sugere haver outros fatores genéticos e näo genéticos de maior magnitude que afetam o peso à desmama

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Weaning weights from a Nelore herd were used after adjustment of means for 205 days of age, sex, age of dam, sire and weaning month, and resulted into two groups of cows that differed by the weaning weight of their calves. The least square means (LSM) and standard error (SE) were for heavy group 163.21± 2.18kg and for light group 134.44± 2.18kg, with 41 animals in each group. These animals were genotyped by DNA polymorphisms of beta -lactoglobulin gene, using PCR-RFLP. After amplification and digestion of a beta-lactoglobulin gene fragment between II and III exon, genotypes 1AA, 24AB and 56BB were identified, with 0.16 and 0.84 frequencies for A and B alleles, respectively. The 24AB and 56BB cows showed calves with LSM± SE of 149.50± 4.17kg and 148.44± 2.73kg respectively, for weaning weight. No difference (P>0.05) was found and the heavy and light groups were similar for the allelic frequencies for this gene. The dam’s genotype did not affect the weaning weight of the calves. This suggests of having other factors, genetic or non-genetic, with major magnitude that affect the weaning weight.

Informações sobre peso à desmama de bezerros Nelore foram utilizadas após ajuste para idade padrão aos 205 dias, sexo, idade da mãe, touro e mês de desmama, para separar as reprodutrizes em dois grupos, segundo o peso de suas crias. As médias de peso dos bezerros ajustadas pelo método dos quadrados mínimos e erros-padrão (LSM± SE) foram para os grupos pesados (P) e leves (L) 163,21± 2,18kg e 134,44± 2,18kg, respectivamente, com 41 animais em cada grupo. Essas reprodutrizes foram submetidas a coleta de sangue para estudo de polimorfismos do gene da beta-lactoglobulina, por meio da técnica de PCR-RFLP. A amplificação e a digestão de um fragmento do gene da beta-lactoglobulina entre o éxon II e III identificou os genótipos 1AA, 24AB e 56BB, com as freqüências de 0,16 e 0,84 para os alelos A e B, respectivamente. Os 24 animais com genótipo AB apresentaram LSM± SE de peso de seus produtos de 149,50± 4,17kg, e os 56 animais de genótipo BB tiveram média de 148,44± 2,73kg. O teste do qui-quadrado não apresentou significância (P>0,05), isto é, os grupos P e L não diferiram entre si quanto às freqüências alélicas apresentadas para esse gene. O genótipo das reprodutrizes não afetou o peso à desmama de suas crias, o que sugere haver outros fatores genéticos e não genéticos de maior magnitude que afetam o peso à desmama.

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Weaning weights from a Nelore herd were used after adjustment of means for 205 days of age, sex, age of dam, sire and weaning month, and resulted into two groups of cows that differed by the weaning weight of their calves. The least square means (LSM) and standard error (SE) were for heavy group 163.21± 2.18kg and for light group 134.44± 2.18kg, with 41 animals in each group. These animals were genotyped by DNA polymorphisms of beta -lactoglobulin gene, using PCR-RFLP. After amplification and digestion of a beta-lactoglobulin gene fragment between II and III exon, genotypes 1AA, 24AB and 56BB were identified, with 0.16 and 0.84 frequencies for A and B alleles, respectively. The 24AB and 56BB cows showed calves with LSM± SE of 149.50± 4.17kg and 148.44± 2.73kg respectively, for weaning weight. No difference (P>0.05) was found and the heavy and light groups were similar for the allelic frequencies for this gene. The dams genotype did not affect the weaning weight of the calves. This suggests of having other factors, genetic or non-genetic, with major magnitude that affect the weaning weight.

Informações sobre peso à desmama de bezerros Nelore foram utilizadas após ajuste para idade padrão aos 205 dias, sexo, idade da mãe, touro e mês de desmama, para separar as reprodutrizes em dois grupos, segundo o peso de suas crias. As médias de peso dos bezerros ajustadas pelo método dos quadrados mínimos e erros-padrão (LSM± SE) foram para os grupos pesados (P) e leves (L) 163,21± 2,18kg e 134,44± 2,18kg, respectivamente, com 41 animais em cada grupo. Essas reprodutrizes foram submetidas a coleta de sangue para estudo de polimorfismos do gene da beta-lactoglobulina, por meio da técnica de PCR-RFLP. A amplificação e a digestão de um fragmento do gene da beta-lactoglobulina entre o éxon II e III identificou os genótipos 1AA, 24AB e 56BB, com as freqüências de 0,16 e 0,84 para os alelos A e B, respectivamente. Os 24 animais com genótipo AB apresentaram LSM± SE de peso de seus produtos de 149,50± 4,17kg, e os 56 animais de genótipo BB tiveram média de 148,44± 2,73kg. O teste do qui-quadrado não apresentou significância (P>0,05), isto é, os grupos P e L não diferiram entre si quanto às freqüências alélicas apresentadas para esse gene. O genótipo das reprodutrizes não afetou o peso à desmama de suas crias, o que sugere haver outros fatores genéticos e não genéticos de maior magnitude que afetam o peso à desmama.

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Informaçöes sobre peso à desmama de um rebanho Nelore foram utilizadas após ajuste para idade padräo de 205 dias, sexo da cria, idade da mäe, touro e mês de desmama, para separar as reprodutrizes em dois grupos, cujos filhos diferiam nesse peso. As médias ajustadas pelo método dos quadrados mínimos foram para os grupos pesado (P) e leve (L) de 163,21ñ2,18kg e 134,44ñ2,18kg, respectivamente, com 41 animais em cada grupo. Essas reprodutrizes foram submetidas à coleta de sangue para estudo de polimorfismos do gene da somatotropina bovina, pela técnica de PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism). A amplificaçäo de uma regiäo entre o éxon III e V do gene da somatotropina permitiu analisar dois sítios de restriçäo. Para o sítio do éxon V, todos os animais foram identificados como monomórficos (Leu-Leu). Quanto ao sítio de íntron 3, foi possível identificar os seguintes genótipos 21 (+/-) e 60 (-/-), com as freqüências de 0,13 e 0,87 para os alelos (+) e (-), respectivamente. O peso dos filhos dos animais com o genótipo +/- foi de 152,42ñ4,41kg e os -/- 147,60 mais ou menos 2,61kg. Os grupos P e L näo diferiram entre si quanto à freqüências alélicas apresentadas. O genótipo das reprodutrizes näo afetou o peso à desmama de suas crias, existindo portanto outros efeitos genéticos e näo genéticos de maior magnitude

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Data from a Nelore herd were used after adjustment of the weaning weight for 205 days of age, sex, age of dam, sire and weaning month and resulted into two groups of cows according to the in weaning weight of their calves (heavy and light groups). The least square means (LSM) for weaning weights were 163.21± 2,18kg and 134,44± 2.18kg, for heavy (H) and light (L) groups, with 41 animals each one. These animals were genotyped for DNA polymorphisms of the bovine somatotropin gene, using PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism). Amplification of a region between exons III and V of somatotropin gene allowed analysis of two restriction sites. All animals showed monomorphism for the V exon site, showing the (Leu-Leu) genotype. At intron 3 site, there were identified the 21+/- and 60 -/- genotypes, with 0.13 and 0.87 frequencies to (+) and (-) alleles, respectively. The calves from +/- counts was of 152.42± 4.41kg and of calves from -/- cows was 147.60± 2.61kg. Heavy and light groups were similar for the allelic frequencies. The dam’s genotype did not affect the weaning weight of the calves. This suggests the existence of another genetic or non-genetic factors with major magnitude.

Informações sobre peso à desmama de um rebanho Nelore foram utilizadas após ajuste para idade padrão de 205 dias, sexo da cria, idade da mãe, touro e mês de desmama, para separar as reprodutrizes em dois grupos, cujos filhos diferiam nesse peso. As médias ajustadas pelo método dos quadrados mínimos foram para os grupos pesado (P) e leve (L) de 163,21± 2,18kg e 134,44± 2,18kg, respectivamente, com 41 animais em cada grupo. Essas reprodutrizes foram submetidas à coleta de sangue para estudo de polimorfismos do gene da somatotropina bovina, pela técnica de PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism). A amplificação de uma região entre o éxon III e V do gene da somatotropina permitiu analisar dois sítios de restrição. Para o sítio do éxon V, todos os animais foram identificados como monomórficos (Leu-Leu). Quanto ao sítio do íntron 3, foi possível identificar os seguintes genótipos 21 (+/-) e 60 (-/-), com as freqüências de 0,13 e 0,87 para os alelos (+) e (-), respectivamente. O peso dos filhos dos animais com o genótipo +/- foi de 152,42± 4,41kg e os -/- 147,60± 2,61kg. Os grupos P e L não diferiram entre si quanto às freqüências alélicas apresentadas. O genótipo das reprodutrizes não afetou o peso à desmama de suas crias, existindo portanto outros efeitos genéticos e não genéticos de maior magnitude.

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Informaçöes sobre peso à desmama de um rebanho Nelore, após ajuste para idade padräo de 205 dias, sexo da cria, idade da mäe, touro e mês de desmama, foram utilizadas para separar as reprodutrizes em dois grupos, cujos produtos diferiam em peso. As médias ajustadas pelo método dos quadrados mínimos e erros-padräo para os grupos pesado (P) e leve (L) foram 163,21ñ2,18kg e 134,44ñ2,18kg, respectivamente, com 41 animais em cada grupo. Colheram-se amostras de sangue das reprodutrizes para o estudo de polimorfismos do gene da k-caseína, pela técnica de polymerase chain reaction-restriction fragment length polymorphism. A análise de um segmento do éxon IV do gene da k-caseína identificou os genótipos 71AA, 10AB e 1BB, com as freqüências de 0,92 e 0,08 para os alelos A e B, respectivamente. Os pesos à desmama dos produtos dos genótipos AA e AB foram, respectivamente, 147,73ñ2,38kg e 156,76ñ6,35kg. Os grupos P e L näo diferiram entre si quanto às freqüências alélicas apresentadas para esse gene. O genótipo das reprodutrizes näo afetou o peso à desmama de suas crias, existindo, portanto, outros efeitos genéticos e näo genéticos de maior magnitude

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