18 resultados para 616.047

em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo (BDPI/USP)


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Introduction: Orthodontic tooth movement uses mechanical forces that result in inflammation in the first days. Myeloperoxidase (MPO) is an enzyme found in polymorphonuclear neutrophil (PMN) granules, and it is used to estimate the number of PMN granules in tissues. So far, MPO has not been used to study the inflammatory alterations after the application of orthodontic tooth movement forces. The aim of this study was to determine MPO activity in the gingival crevicular fluid (GCF) and saliva (whole stimulated saliva) of orthodontic patients at different time points after fixed appliance activation. Methods: MPO was determined in the GCF and collected by means of periopaper from the saliva of 14 patients with orthodontic fixed appliances. GCF and saliva samples were collected at baseline, 2 hours, and 7 and 14 days after application of the orthodontic force. Results: Mean MPO activity was increased in both the GCF and saliva of orthodontic patients at 2 hours after appliance activation (P<0.02 for all comparisons). At 2 hours, PMN infiltration into the periodontal ligament from the orthodontic force probably results in the increased MPO level observed at this time point. Conclusions: MPO might be a good marker to assess inflammation in orthodontic movement; it deserves further studies in orthodontic therapy. (Am J Orthod Dentofacial Orthop 2010;138:613-6)

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Some vocal disorders in teachers are associated with occupational factors, but there are few studies that analyze the influence of vocal habits, fluid intake, mastication, and sleep on these disorders. The objective was to analyze the Occurrence of vocal fatigue, hoarseness, and dry throat in elementary and high school teachers and their association with vocal habits, fluid intake, mastication, and sleep. A sample of 422 elementary and secondary school teachers was Studied using a specific questionnaire. The multiple regression analysis showed that hoarseness was associated with absence of water intake (odds ratio (OR) = 1.7; P = 0.047), yelling/speaking loudly (OR = 1.6; P = 0.058), jaw-opening limitations (OR = 3.8; P = 0.003). average of: 6 hours of sleep/light (OR = 1.7; P = 0.039), and waking-up feeling replenished (OR = 2.0; P = 0.020). The presence of vocal fatigue was significantly associated with yelling/speaking loudly (OR = 2.2: P = 0.013), speaking excessively (OR = 2.4; P = 0.023), difficulty to open the mouth to masticate (OR = 6.6; P = 0.003), less than 6 hours of sleep (OR = 4.0; P = 0.008), and waking-up feeling replenished (sometimes OR = 2.8: P = 0.003; or never OR = 3.3 P = 0.002). The presence of dry throat was associated with being a former smoker (OR = 3.3; P = 0.011) and having jaw-opening limitations (OR = 3.9; P = 0.021). In recent years, speech and hearing interventions with teachers have focused on health-care promotion actions and prevention of vocal disorders, prioritizing issues related with hydration and healthy vocal use habits. However, the findings in the present study show the need to further focus on lifestyle habits related to sleep and eating habits.

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Background & aims: Pregnancy is a period characterized by high metabolic requirements and physiological changes in the female organism. During this period, Low body stores of vitamins and minerals including antioxidants can have adverse effects on the mother and foetus. This cross-sectional. study assessed plasma concentrations of ascorbic acid (AA) in 117 parturients admitted into a university hospital in S (a) over tildeo Paulo city, Brazil. Methods: The concentrations of AA were determined by the high performance liquid chromatographic method. Data concerning socioeconomic, demographic, obstetric and nutritional characteristics of the parturients were collected by a standardized questionnaire. Results: The prevalence of AA deficiency (< 22.7 mu mol/L) among the parturients was 30.8%. Mean plasma AA concentrations were lower in single/divorced women (27.84 +/- 3.48 mu mol./L) compared with married/single with partner women (34.78 +/- 1.85 mu mol/L) (p = 0.047). Blood AA concentrations were significantly correlated with per capita income (r = 0.36, p < 0.001) and vitamin C-rich food intake score (r = 0.42, p < 0.001). Conclusion: The high prevalence of hypovitaminosis C detected in this study is probably due to an inadequate intake of foods rich in vitamin C and tow income. We alert to the need for increasing the intake of vitamin C-rich foods through educational. programs, especially for tow income populations. (c) 2007 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

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In this study, observations and numerical simulations are used to investigate how different El Nino events affect the development of SST anomalies in the Atlantic and how this relates to the Brazilian northeast (NE) precipitation. The results show that different types of El Nino have different impacts on the SST anomalies of the equatorial and tropical South Atlantic but a similar SST response in the tropical North Atlantic. Strong and long (weak and short) El Ninos with the main heating source located in the eastern (central) Pacific generate cold (warm) anomalies in the cold tongue and Benguela upwelling regions during boreal winter and spring. When the SST anomalies in the eastern equatorial and tropical South Atlantic are cold (warm), the meridional SST gradient across the equator is positive (negative) and the ITCZ is not allowed (allowed) to move southward during the boreal spring; as a consequence, the precipitation is below (above) the average over the NE. Thus, strong and long (weak and short) El Ninos are followed by dry (wet) conditions in the NE. During strong and long El Ninos, changes in the Walker circulation over the Atlantic and in the Pacific-South Atlantic (PSA) wave train cause easterly wind anomalies in the western equatorial Atlantic, which in turn activate the Bjerknes mechanism, establishing the cold tongue in boreal spring and summer. These easterly anomalies are also responsible for the Benguela upwelling. During short and weak El Ninos, westerly wind anomalies are present in the western equatorial Atlantic accompanied by warm anomalies in the eastern equatorial and tropical South Atlantic; a positive phase of the South Atlantic dipole develops during boreal winter. The simulations highlight the importance of ocean dynamics in establishing the correct slope of the equatorial thermocline and SST anomalies, which in turn determine the correct rainfall response over the NE.

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Small local earthquakes from two aftershock sequences in Porto dos GaA(0)chos, Amazon craton-Brazil, were used to estimate the coda wave attenuation in the frequency band of 1 to 24 Hz. The time-domain coda-decay method of a single backscattering model is employed to estimate frequency dependence of the quality factor (Q (c)) of coda waves modeled usingwhere Q (0) is the coda quality factor at frequency of 1 Hz and eta is the frequency parameter. We also used the independent frequency model approach (Morozov, Geophys J Int, 175:239-252, 2008), based in the temporal attenuation coefficient, chi(f) instead of Q(f), given by the equation for the calculation of the geometrical attenuation (gamma) and effective attenuation Q (c) values have been computed at central frequencies (and band) of 1.5 (1-2), 3.0 (2-4), 6.0 (4-8), 9.0 (6-12), 12 (8-16), and 18 (12-24) Hz for five different datasets selected according to the geotectonic environment as well as the ability to sample shallow or deeper structures, particularly the sediments of the Parecis basin and the crystalline basement of the Amazon craton. For the Parecis basin for the surrounding shield and for the whole region of Porto dos GaA(0)chos Using the independent frequency model, we found: for the cratonic zone, gamma = 0.014 s (-aEuro parts per thousand 1), nu a parts per thousand 1.12; for the basin zone with sediments of similar to 500 m, gamma = 0.031 s (-aEuro parts per thousand 1), nu a parts per thousand 1.27; and for the Parecis basin with sediments of similar to 1,000 m, gamma = 0.047 s (-aEuro parts per thousand 1), nu a parts per thousand 1.42. Analysis of the attenuation factor (Q (c)) for different values of the geometrical spreading parameter (nu) indicated that an increase of nu generally causes an increase in Q (c), both in the basin as well as in the craton. But the differences in the attenuation between different geological environments are maintained for different models of geometrical spreading. It was shown that the energy of coda waves is attenuated more strongly in the sediments, (in the deepest part of the basin), than in the basement, (in the craton). Thus, the coda wave analysis can contribute to studies of geological structures in the upper crust, as the average coda quality factor is dependent on the thickness of sedimentary layer.

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Endospermic legumes are abundant in tropical forests and their establishment is closely related to the mobilization of cell-wall storage polysaccharides. Endosperm cells also store large numbers of protein bodies that play an important role as a nitrogen reserve in this seed. In this work, a systems approach was adopted to evaluate some of the changes in carbohydrates and hormones during the development of seedlings of the rain forest tree Sesbania virgata during the period of establishment. Seeds imbibed abscisic acid (ABA), glucose and sucrose in an atmosphere of ethylene, and the effects of these compounds on the protein contents, alpha-galactosidase activity and endogenous production of ABA and ethylene by the seeds were observed. The presence of exogenous ABA retarded the degradation of storage protein in the endosperm and decreased alpha-galactosidase activity in the same tissue during galactomannan degradation, suggesting that ABA represses enzyme action. On the other hand, exogenous ethylene increased alpha-galactosidase activity in both the endosperm and testa during galactomannan degradation, suggesting an inducing effect of this hormone on the hydrolytic enzymes. Furthermore, the detection of endogenous ABA and ethylene production during the period of storage mobilization and the changes observed in the production of these endogenous hormones in the presence of glucose and sucrose, suggested a correlation between the signalling pathway of these hormones and the sugars. These findings suggest that ABA, ethylene and sugars play a role in the control of the hydrolytic enzyme activities in seeds of S. virgata, controlling the process of storage degradation. This is thought to ensure a balanced flow of the carbon and nitrogen for seedling development.

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Samples from 30 deaf probands exhibiting features suggestive of syndromic mitochondrial deafness or from families with maternal transmission of deafness were selected for investigation of mutations in the mitochondrial genes MT-RNR1 and MT-TS1. Patients with mutation m. 1555A>G had been previously excluded from this sample. In the MT-RNR1 gene, five probands presented the m. 827A>G sequence variant, of uncertain pathogenicity. This change was also detected in 66 subjects of an unaffected control sample of 306 Brazilian individuals from various ethnic backgrounds. Given its high frequency, we consider it unlikely to have a pathogenic role on hereditary deafness. As to the MT-TS1 gene, one proband presented the previously known pathogenic m. 7472insC mutation and three probands presented a novel variant, m. 7462C>T, which was absent from the same control sample of 306 individuals. Because of its absence in control samples and association with a family history of hearing impairment, we suggest it might be a novel pathogenic mutation.

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Background: The chromosome 17q21.31 microdeletion syndrome is a novel genomic disorder that has originally been identified using high resolution genome analyses in patients with unexplained mental retardation. Aim: We report the molecular and/or clinical characterisation of 22 individuals with the 17q21.31 microdeletion syndrome. Results: We estimate the prevalence of the syndrome to be 1 in 16 000 and show that it is highly underdiagnosed. Extensive clinical examination reveals that developmental delay, hypotonia, facial dysmorphisms including a long face, a tubular or pear-shaped nose and a bulbous nasal tip, and a friendly/amiable behaviour are the most characteristic features. Other clinically important features include epilepsy, heart defects and kidney/urologic anomalies. Using high resolution oligonucleotide arrays we narrow the 17q21.31 critical region to a 424 kb genomic segment (chr17: 41046729-41470954, hg17) encompassing at least six genes, among which is the gene encoding microtubule associated protein tau (MAPT). Mutation screening of MAPT in 122 individuals with a phenotype suggestive of 17q21.31 deletion carriers, but who do not carry the recurrent deletion, failed to identify any disease associated variants. In five deletion carriers we identify a <500 bp rearrangement hotspot at the proximal breakpoint contained within an L2 LINE motif and show that in every case examined the parent originating the deletion carries a common 900 kb 17q21.31 inversion polymorphism, indicating that this inversion is a necessary factor for deletion to occur (p< 10(25)). Conclusion: Our data establish the 17q21.31 microdeletion syndrome as a clinically and molecularly well recognisable genomic disorder.

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STUDY DESIGN: Randomized crossover double-blinded placebo-controlled trial. OBJECTIVE: To investigate if low-level laser therapy (LLLT) can affect biceps muscle performance, fatigue development, and biochemical markers of postexercise recovery. BACKGROUND: Cell and animal studies have suggested that LLLT can reduce oxidative stress and inflammatory responses in muscle tissue. But it remains uncertain whether these findings can translate into humans in sport and exercise situations. METHODS: Nine healthy male volleyball players participated in the study. They received either active LLLT (cluster probe with 5 laser diodes; A = 810 nm; 200 mW power output; 30 seconds of irradiation, applied in 2 locations over the biceps of the nondominant arm; 60 J of total energy) or placebo LLLT using an identical cluster probe. The intervention or placebo were applied 3 minutes before the performance of exercise. All subjects performed voluntary elbow flexion repetitions with a workload of 75% of their maximal voluntary contraction force until exhaustion. RESULTS: Active LLLT increased the number of repetitions by 14.5% (mean +/- SD, 39.6 +/- 4.3 versus 34.6 +/- 5.6; P = .037) and the elapsed time before exhaustion by 8.0% (P = .034), when compared to the placebo treatment. The biochemical markers also indicated that recovery may be positively affected by LLLT, as indicated by postexercise blood lactate levels (P<.01), creatine kinase activity (P = .017), and C-reactive protein levels (P = .047), showing a faster recovery with LLLT application prior to the exercise. CONCLUSION: We conclude that pre-exercise irradiation of the biceps with an LLLT dose of 6 J per application location, applied in 2 locations, increased endurance for repeated elbow flexion against resistance and decreased postexercise levels of blood lactate, creatine kinase, and C-reactive protein. LEVEL OF EVIDENCE: Performance enhancement, level 1b. J Orthop Sports Phys Ther 2010;40(8):524-532. doi:10.2519/jospt.2010.3294

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Heme oxygenase-1 (HO-1) has a microsatellite polymorphism based on the number of guanosine-thymidine nucleotide repeats (GT) repeats that regulates expression levels and could have an impact on organ survival post-injury. We correlated HO-1 polymorphism with renal graft function. The HO-1 gene was sequenced (N = 181), and the allelic repeats were divided into subclasses: short repeats (S) (< 27 repeats) and long repeats (L) (>= 27 repeats). A total of 47.5% of the donors carried the S allele. The allograft function was statistically improved six months, two and three yr after transplantation in patients receiving kidneys from donors with an S allele. For the recipients carrying the S allele (50.3%), the allograft function was also better throughout the follow-up, but reached statistical significance only three yr after transplantation (p = 0.04). Considering only those patients who had chronic allograft nephropathy (CAN; 74 of 181), allograft function was also better in donors and in recipients carrying the S allele, two and three yr after transplantation (p = 0.03). Recipients of kidney transplantation from donors carrying the S allele presented better function even in the presence of CAN.

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The effects of verapamil modulating collagen biosynthesis have prompted us to study the role of this drug in cultured fibroblasts. In this article, we describe the effects of verapamil on fibroblast behaviour, with special emphasis to phenotypic modifications, reorganisation of actin filaments and secretion of MMP1. Human dermal fibroblasts treated with 50-mu M verapamil changed their normal spindle-shaped morphology to stellate. Treated cells showed discrete reorganisation of actin filaments, as revealed by fluorescein isothiocyanate (FITC)-phalloidin staining and confocal microscopy. We hypothesised that these effects would be associated to lower levels of cytosolic Ca(2+). Indeed, short time loading with calcium green confirmed that verapamil-treated fibroblasts exhibited lower intracellular calcium levels compared to controls. We also observed that verapamil increases the secretion of MMP1 in cultured fibroblasts, as demonstrated by zymography, specific substrate assays and immunoblot. The morphological alterations induced by verapamil are neither cytotoxic nor associated with other dramatic cytoskeleton alterations. Thus we may conclude that this drug enhances collagenase secretion and does not disrupt the major tracks necessary to deliver these enzymes in the extracellular space. The present results suggested that verapamil could be used at physiological levels to enhance collagen I breakdown, and maybe considered a potential candidate for intralesional therapy of wound healing and fibrocontractive diseases. (C) 2010 Elsevier Ltd and ISBI. All rights reserved.

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This paper addresses the independent multi-plant, multi-period, and multi-item capacitated lot sizing problem where transfers between the plants are allowed. This is an NP-hard combinatorial optimization problem and few solution methods have been proposed to solve it. We develop a GRASP (Greedy Randomized Adaptive Search Procedure) heuristic as well as a path-relinking intensification procedure to find cost-effective solutions for this problem. In addition, the proposed heuristics is used to solve some instances of the capacitated lot sizing problem with parallel machines. The results of the computational tests show that the proposed heuristics outperform other heuristics previously described in the literature. The results are confirmed by statistical tests. (C) 2009 Elsevier B.V. All rights reserved.

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This paper presents an overview of the results obtained during the Joint Experiments organized in the framework of the IAEA Coordinated Research Project on `Joint Research Using Small Tokamaks` that have been carried out on the tokamaks CASTOR at IPP Prague, Czech Republic (2005), T-10 at RRC `Kurchatov Institute`, Moscow, Russia (2006), and the most recent one at ISTTOK at IST, Lisbon, Portugal, in 2007. Experimental programmes were aimed at diagnosing and characterizing the core and the edge plasma turbulence in a tokamak in order to investigate correlations between the occurrence of transport barriers, improved confinement, electric fields and electrostatic turbulence using advanced diagnostics with high spatial and temporal resolution. On CASTOR and ISTTOK, electric fields were generated by biasing an electrode inserted into the edge plasma and an improvement of the global particle confinement induced by the electrode positive biasing has been observed. Geodesic acoustic modes were studied using heavy ion beam diagnostics on T-10 and ISTTOK and correlation reflectometry on T-10. ISTTOK is equipped with a gallium jet injector and the technical feasibility of gallium jets interacting with plasmas has been investigated in pulsed and ac operation. The first Joint Experiments have clearly demonstrated that small tokamaks are suitable for broad international cooperation to conduct dedicated joint research programmes. Other activities within the IAEA Coordinated Research Project on Joint Research Using Small Tokamaks are also overviewed.

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We study the effect of thermal disorder on the electronic structure of one-dimensional poly-para-phenylene (PPP). In a real chain the torsion angles between rings are bound to be distributed over a range of values, which depend on temperature, and thus the chain is intrinsically disordered. In this study we simulated this kind of thermally induced off-diagonal disorder through the simple Huckel method. We base our Hamiltonian on ab initio results for the effect of temperature on torsion angles, and the effect of torsion angles on the energy gap. We analyze the electronic structure of 200-monomer-long chains focusing on the density of states, and the associated localization character (measured by the inverse participation ratio). Our results contrast with the usually assumed Gaussian-shaped density of localized states for disordered systems. (C) 2009 Elsevier B.V. All rights reserved.

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This paper describes the preparation of a biomimetic Langmuir-Blodgett film of tyrosinase incorporated in a lipidic layer and the use of lutetium bisphthalocyanine as an electron mediator for the voltammetric detection of phenol derivatives, which include one monophenol (vanillic acid), two diphenols (catechol and caffeic acid) and two triphenols (gallic acid and pyrogallol). The first redox process of the voltammetric responses is associated with the reduction of the enzymatically formed o-quinone and is favoured by the lutetium bisphthalocyanine because significant signal amplification is observed, while the second is associated with the electrochemical oxidation of the antioxidant and occurs at lower potentials in the presence of an electron mediator. The biosensor shows low detection limit (1.98 x 10(-6)-27.49 x 10(-6) M), good reproducibility, and high affinity to antioxidants (Km in the range of 62.31-144.87 mu M). The excellent functionality of the enzyme obtained using a biomimetic immobilisation method, the selectivity afforded by enzyme catalysis, the signal enhancement caused by the lutetium bisphthalocyanine mediator and the increased selectivity of the curves due to the occurrence of two redox processes make these sensors exceptionally suitable for the detection of phenolic compounds. (C) 2010 Elsevier B.V. All rights reserved.