10 resultados para 835
em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo
Resumo:
Sugarcane-breeding programs take at least 12 years to develop new commercial cultivars. Molecular markers offer a possibility to study the genetic architecture of quantitative traits in sugarcane, and they may be used in marker-assisted selection to speed up artificial selection. Although the performance of sugarcane progenies in breeding programs are commonly evaluated across a range of locations and harvest years, many of the QTL detection methods ignore two- and three-way interactions between QTL, harvest, and location. In this work, a strategy for QTL detection in multi-harvest-location trial data, based on interval mapping and mixed models, is proposed and applied to map QTL effects on a segregating progeny from a biparental cross of pre-commercial Brazilian cultivars, evaluated at two locations and three consecutive harvest years for cane yield (tonnes per hectare), sugar yield (tonnes per hectare), fiber percent, and sucrose content. In the mixed model, we have included appropriate (co)variance structures for modeling heterogeneity and correlation of genetic effects and non-genetic residual effects. Forty-six QTLs were found: 13 QTLs for cane yield, 14 for sugar yield, 11 for fiber percent, and 8 for sucrose content. In addition, QTL by harvest, QTL by location, and QTL by harvest by location interaction effects were significant for all evaluated traits (30 QTLs showed some interaction, and 16 none). Our results contribute to a better understanding of the genetic architecture of complex traits related to biomass production and sucrose content in sugarcane.
Resumo:
Objectives: The aim of this study was to identify communities at high risk of transmitting recessive genetic disorders by measuring levels of endogamy and offspring's rate of disabilities. Methods: In a house-to-house population based-survey in the state of Paraiba, 20,462 couples were interviewed regarding kinship relation, number of siblings and offspring affected by mental or physical disabilities. Results: The rate of consanguineous unions in the communities ranged from 6.0% to 41.14%, showing an average value of 20.19% +/- 9.13%. The overall average inbreeding coefficient (F) was 0.00602 +/- 0.00253, ranging from 0.00134 to 0.01182. Communities situated on the backlands had an increased average value of F compared to those closer to the seashore (P = 0.024). The average rate of disabled offspring varied from 2.96% +/- 0.68% for unrelated unions to 10.44% +/- 16.86% for related couples at the level of double first cousins or uncleniece. The Spearman correlation coefficient between the overall rate of disabled offspring from all couples together and F was 0.510 (P < 0.01). Conclusion: Inbreeding increases the risk of disability which is unevenly distributed, varying considerably even in neighboring communities with similar Human Development Index and population density. Higher inbreeding communities are mostly located on the more economically underdeveloped backlands than on the coastal region. The identification of communities at high risk for genetic disorders could serve as basis for the establishment of Community Genetics programs. Am. J. Hum. Biol., 2012. (C) 2012 Wiley Periodicals, Inc.
Resumo:
Background: Recent studies have identified that a higher resting heart rate (RHR) is associated with elevated blood pressure, independent of body fatness, age and ethnicity. However, it is still unclear whether RHR can also be applied as a screening for other risk factors, such as hyperglycemia and dyslipidemia. Thus, the purpose of the presented study was to analyze the association between RHR, lipid profile and fasting glucose in obese children and adolescents. Methods: The sample was composed of 180 obese children and adolescents, aged between 7-16 years. Whole-body and segmental body composition were estimated by Dual-energy X-ray absorptiometry. Resting heart rate (RHR) was measured by heart rate monitors. The fasting blood samples were analyzed for serum triglycerides, total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and glucose, using the colorimetric method. Results: Fasting glucose, TC, triglycerides, HDL-C, LDL-C and RHR were similar in both genders. The group of obese subjects with a higher RHR presented, at a lower age, higher triglycerides and TC. There was a significant relationship between RHR, triglycerides and TC. In the multivariate model, triglycerides and TC maintained a significant relationship with RHR independent of age, gender, general and trunk adiposity. The ROC curve indicated that RHR has a high potential for screening elevated total cholesterol and triglycerides as well as dyslipidemia. Conclusion: Elevated RHR has the potential to identify subjects at an increased risk of atherosclerosis development.
Resumo:
The objective of this study was to evaluate the effects of adding alkalis on the fermentative pattern, aerobic stability and nutritive value of the sugarcane silage. A completely randomized design with 6 additives in two concentrations (1 or 2%), plus a control group, totalizing 13 treatments [(6x2)+1] with four replications, was used. The additives were sodium hydroxide (NaOH), limestone (CaCO3), urea (CO(NH2)(2)), sodium bicarbonate (NaHCO3), quicklime (CaO) and hydrated lime (Ca(OH)(2)). The material was ensiled in 52 laboratory silos using plastic buckets with 12 L of capacity. Silos were opened 60 days after ensiling, when organic acids concentration, aerobic stability and chemical composition were determined. The Relative Biological Efficiency (RBE) was calculated by the slope ratio method, using the data obtained from ratio between desirable and undesirable silage products, according to the equation: D/U ratio = [lactic/(ethanol + acetic + butyric)]. All additives affected dry matter, crude protein, acid detergent fiber, neutral detergent fiber contents and buffering capacity. Except for urea and quicklime, all additives increased the in vitro dry matter digestibility. In general, these additives altered the fermentative pattern of sugarcane silage, inhibiting alcoholic fermentation and improving lactic acid production. The additive that showed the best RBE in relation to sodium hydroxide (100%) was limestone (89.4%). The RBE values of urea, sodium bicarbonate and hydrated lime were 49.2%, 47.7% and 34.3%, respectively.
Resumo:
BACKGROUND: There are several techniques for screw insertion in upper cervical spine surgery, and the use of the 3.5-mm screw is usually the standard. However, there is no consensus regarding the feasibility of using these screws in the pediatric population. OBJECTIVE: To determine the measurement of the lamina angle, lamina and pedicle length and thickness, and lateral mass length of the topographic axial view of the axis vertebra of 2- to 10-year-old children to guide the use of surgical screws. METHODS: Seventy-five computed tomography scans from 24- to 120-month-old patients were studied. Measurements were taken in an axial view of C2 and correlated with 2 age groups and both sexes. Statistical analysis was performed with the Student t test. RESULTS: In the 24- to 48-month age group, only 5.5% of the lamina and 8.3% of the pedicles had thicknesses < 3.5 mm. In the 49- to 120-month age group, there were no lamina thickness values < 3.5 mm, and 1.2% of pedicle thicknesses were < 3.5 mm. Both age groups had no lamina and pedicle lengths < 12 mm and no lateral mass lengths > 12 mm. CONCLUSION: In the majority of cases, the use of 3.5-mm lamina and pedicle screws in children is feasible. A base value of 45 degrees for the spinolaminar angle can be adopted as a reference for insertion of screws in the C2 lamina. This information can be particularly useful for decision making during preoperative planning for C1-C2 or craniocervical arthrodesis in children.
Resumo:
In response to pathogen recognition by Toll-like receptors (TLRs) on their cell surface, macrophages release lipid mediators and cytokines that are widely distributed throughout the body and play essential roles in host responses. Granulocyte macrophage colony-stimulating factor (GM-CSF) is important for the immune response during infections to improve the clearance of microorganisms. In this study, we examined the release of mediators in response to TLR2 ligands by bone marrow-derived macrophages (BMDMs) primed with GM-CSF. We demonstrated that when stimulated with TLR2 ligands, non-primed BMDMs preferentially produced PGE(2) in greater amounts than LTB4. However, GM-CSF priming shifted the release of lipid mediators by BMDMs, resulting in a significant decrease of PGE(2) production in response to the same stimuli. The decrease of PGE(2) production from primed BMDMs was accompanied by a decrease in PGE-synthase mRNA expression and an increase in TNF-alpha and nitric oxide (NO) production. Moreover, some GM-CSF effects were potentiated by the addition of IFN-gamma. Using a variety of TLR2 ligands, we established that PGE(2) release by GM-CSF-primed BMDMs was dependent on TLR2 co-receptors (TLR1, TLR6), CD14, MyD88 and the nuclear translocation of NF kappa B but was not dependent on peroxisome proliferator-activated receptor-gamma (PPAR-gamma) activation. Indeed, GM-CSF priming enhanced TLR2, TLR4 and MyD88 mRNA expression and phospho-I kappa B alpha formation. These findings demonstrate that GM-CSF drives BMDMs to present a profile relevant to the host during infections.
Male dimorphism of a neotropical arachnid: harem size, sneaker opportunities, and gonadal investment
Resumo:
Serracutisoma proximum is a harvestman with alternative male morphs. Large males use sexually dimorphic second legs in fights for the possession of territories on the vegetation, where females oviposit. Small males have short second legs and do not fight but rather sneak into the territories and copulate with egg-guarding females. We investigated the presence of male dimorphism across 10 populations of S. proximum, compared gonadal investment between male morphs, and assessed if the distribution of the sneakers is influenced by harem size. In all populations, there was male dimorphism, indicated by the bimodal distribution of the leg II length/body length. Gonadal investment did not differ between morphs and was not affected by male size, second leg length, and morph relative frequency in the populations. We found 361 territories, 90.0% containing 1 male, 9.7% containing 2 males (dyads), and 0.3% containing 3 males. The probability of encountering dyads increased with the number of females present in the territories. Moreover, the proportion of sneakers in territories containing dyads was higher than would be expected by chance. One possible reason for the ubiquity of alternative morphs in S. proximum could be the high mating opportunities experienced by sneakers in spatially structured populations with a resource defense polygyny system. Additionally, the high frequency of successful invasions by sneakers and hence the high sperm competition risk for both morphs may explain the similarity in gonadal investment between male morphs.
Resumo:
In this work, it was evaluated the effect of moisture content on the structural and dielectric properties of cassava starch films by means of Fourier Transform infrared spectroscopy (FTIR), impedancimetric, and gravimetric analysis. The film samples were equilibrated in hermetically sealed desiccators, containing different saturated salts in water in order to promote activity of water between 0.11 and 0.85. The position and amplitude of the peaks in the fingerprint region of the FTIR spectra were changed due to the modifications in the interactions between the polymeric chains and water molecules. These effects may be related to the formation of semi-crystalline regions in the film structure. The dielectric properties of the films were also strongly dependent on the moisture content, showing a non-linear and a linear region, which was attributed to the domain of bound and free water in the film, respectively. The gravimetric analyzes showed the typical sigmoidal behavior, attributed to the way the water interacts with the biopolymer. Finally, the flexibility of the films increased with water content increasing.
Resumo:
OBJETIVO: avaliar e caracterizar o desempenho escolar de crianças com deficiência auditiva usuárias de implante coclear, entre 9 e 12 anos, assim como, verificar o tempo que a criança leva para acessar a informação fonológica e confrontar estes resultados de acordo com o gênero e série dos participantes. MÉTODO: participaram deste estudo 32 crianças, de ambos os gêneros, freqüentando da primeira a quinta séries do ensino fundamental, regularmente matriculadas no Centro de Pesquisas Audiológicas do Hospital de Reabilitação de Anomalias Craniofaciais, Universidade de São Paulo, na cidade de Bauru/SP. Os instrumentos utilizados foram o Teste de Desempenho Escolar (TDE) e o Teste de Nomeação Automática Rápida (RAN). RESULTADOS: os resultados mostraram que 74% das crianças apresentaram desempenho escolar geral abaixo do esperado, com maior dificuldade na escrita e dentro da média para o tempo que levam ao processar a informação. CONCLUSÕES: concluiu-se que 74% das crianças apresentaram desempenho escolar inferior nas avaliações e que não houve relação entre estes resultados com a nomeação rápida, já que este está dentro da média e é um pré-requisito para a leitura, e os participantes deste estudo apresentam habilidade satisfatória para a leitura.
Resumo:
The aim of this work was to review the role of the host marking pheromone (HMP) and its application in integrated management programs for the fruit flies. Initially the oviposition behavior of tephritids has been analyzed with emphasis on Ceratitis capitata. The deposition of HMP, which consists in the last stage of the oviposition behavior has been characterized and discussed about evolutive aspects and the biological meaning of the tephritidae communication through the HMP. Finally, the perspectives on the use of HMP in the integrated management of fruit flies have been discussed.