298 research outputs found

    Dynamics of magneto electro elastic curved beams: Quantification of parametric uncertainties

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    The objective of this paper is the evaluation of uncertainty propagation associated to several parameters in the dynamics of magneto-electro-elastic (MEE) curved beams. These MEE structures can be employed as imbedded parts in high performance technological systems to control motions and/or attenuate vibrations, for energy harvesting, etc. Although a lot of research connected with these structures was done for dynamics and statics, it is remarkable the scarcity of articles analyzing random dynamics of MEE structure, provided that many models have uncertainties associated to their parameters: loads and/or material properties, among others. A theory for MEE curved beams is derived and assumed as the deterministic model. The response is calculated by means of a finite element formulation. The probabilistic model is constructed appealing to the finite element formulation of the deterministic approach, by adopting random variables for the uncertain parameters selected. The probability density functions of the random variables are derived with the Maximum Entropy Principle. The Monte Carlo method is used to perform simulations with independent realizations. Studies are carried out in order to evaluate the influence of Magneto-elastic and/or piezoelectric coupling in the dynamics of MEE curved beams in both contexts: the deterministic and the stochastic.Fil: Piovan, Marcelo Tulio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca; Argentina. Universidad Tecnológica Nacional. Facultad Regional Bahía Blanca; Argentina. Universidad de las Fuerzas Armadas; EcuadorFil: Olmedo, J. F.. Universidad de las Fuerzas Armadas; EcuadorFil: Sampaio, Rubens. Pontifícia Universidade Católica do Rio de Janeiro; Brasi

    GENDER DIFFERENCES in METABOLIC PROFILE and CARDIOVASCULAR RISK AMONG BRAZILIAN HIV-INFECTED PATIENTS ON HAART: RAPID II STUDY

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    Universidade Federal de São Paulo, São Paulo, BrazilInst Infectol Emilio Ribas, São Paulo, BrazilHosp & Maternidade Celso Pierro, Campinas, SP, BrazilUniv Fed Bahia, Salvador, BA, BrazilBristol Myers Squibb Co, São Paulo, BrazilBristol Myers Squibb Co, Plainsboro, NJ USAHosp Correia Picanco, Recife, PE, BrazilUniversidade Federal de São Paulo, São Paulo, BrazilWeb of Scienc

    Associação entre variantes do gene de leptina e obesidade e biomarcadores metabólicos em indivíduos brasileiros

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    OBJECTIVE: The relationship between variants of the leptin gene (LEP) and obesity and metabolic biomarkers was investigated in Brazilian individuals. SUBJECTS AND METHODS: One-hundred-ten obese (BMI > 30 kg/m²) and 100 non-obese individuals (145 women and 65 men, aged 49 ± 14 years) were randomly selected. Plasma leptin, glycemia, serum lipid measurements and LEP -2548G>A and 3'HVR polymorphisms were analyzed. RESULTS: The LEP -2548GG genotype was associated with a 2.2% and 2.0% increase in BMI (p = 0.009) and plasma leptin (p = 0.031), respectively. 3'HVR I/II (classes I/I+I/II) genotypes contributed with 1.8% of BMI values (p = 0.046). LEP I/G combined genotypes (I/IGG, I/IGA and I/IIGG) were associated with obesity, and increased BMI, waist circumference, leptin and triglycerides (p < 0.05). These relationships were found in women (p < 0.05) but not in men. LEP I/G combined genotypes were not associated with hypertension, hyperglycemia, dyslipidemia and coronary artery disease. CONCLUSIONS: LEP I/G combined genotypes are associated with obesity-related metabolic biomarkers and phenotype in a gender-dependent manner.OBJETIVO: A relação entre as variantes do gene da leptina (LEP) e obesidade e biomarcadores metabólicos foi investigada em indivíduos brasileiros. SUJEITOS E MÉTOODS: Cento e dez indivíduos obesos (IMC > 30 kg/m²) e 100 não obesos (145 mulheres e 65 homens, idade 49 ± 14 anos) foram selecionados aleatoriamente. Leptina plasmática, glicemia, lípides séricos e polimorfismos LEP -2548G>A e 3'HVR foram analisados. RESULTADOS: O genótipo -2548GG foi associado com aumento de 2,2% e 2,0% no IMC (p = 0,009) e leptina plasmática (p = 0,031), respectivamente, enquanto os genótipos 3´HVR I/II (classes I/I+I/II) contribuíram com 1,8% dos valores de IMC (p = 0,046). Os genótipos combinados LEP I/G (I/IGG, I/IGA e I/IIGG) foram associados com obesidade e IMC aumentado, circunferência abdominal, leptina e triglicérides aumentados (p < 0,05). Essas relações foram encontradas em mulheres (p < 0,05), mas não em homens. Os genótipos LEP I/G combinados não foram associados com hipertensão, hiperglicemia, dislipidemia e doença arterial coronariana. CONCLUSÕES: Genótipos combinados LEP I/G são associados com biomarcadores metabólicos e fenótipo de obesidade de forma gênero-dependente

    Polimorfismo do promotor do gene da leptina está associado ao aumento de leptina plasmática e IMC em mulheres brasileiras

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    Variants in leptin gene (LEP) have been implicated in the pathogenesis of obesity. The relationship between LEP G-2548A polymorphism and obesity-related traits was evaluated in a sample of Brazilian women (n = 228) who were randomly selected from two clinical centers in Sao Paulo city. Blood samples were collected for DNA extraction, plasma leptin and serum lipids measurements. LEP G-2548A genotypes were identified by a PCR- RFLP strategy using the endonuclease Alw44I. LEP G-2548A was associated with obesity after adjustment for covariates (age, hypertension, coronary artery disease, smoking and physical activity). Women carrying G allele had a four times higher risk of obesity than the A allele carriers (OR: 4.11, CI95%: 1.06-15.90, p = 0.041). G allele was also related to increased plasma leptin (p = 0.024) and body mass index (p = 0.027). Hypertension, hyperglycemia, dyslipidemia and coronary artery disease were associated with obesity. However LEP G-2548A polymorphism was not related to these variables. All together these data suggest that LEP G-2548A polymorphism has an important role in regulating plasma leptin levels and body mass index in women.Variantes no gene da leptina (LEP) foram implicados na patogênese da obesidade. A relação entre o polimorfismo LEP G-2548A e as características relacionadas com a obesidade foram avaliadas em mulheres brasileiras (n = 228), que foram selecionadas randomicamente de dois centros de pesquisa clínica na cidade de São Paulo. As amostras de sangue foram coletadas para extração de DNA e determinações de leptina plasmática e lipídeos séricos. Os genótipos do LEP G-2548A foram identificados pela estratégia de PCR-RFLP, empregando a endonuclease Alw44I. O polimorfismo LEP G-2548A foi associado com obesidade, após ajuste para as covariáveis: idade, hipertensão, doença arterial coronariana, tabagismo e atividade física. Mulheres com alelo G tiveram quatro vezes maior risco de obesidade que as portadoras do alelo A (OR: 4,11, CI95%: 1,06-15,90; p = 0,041). O alelo G também foi relacionado com leptina plasmática (p = 0,024) e o índice de massa corporal (p = 0,027) aumentado. A hipertensão, a hiperglicemia, a dislipidemia e a doença arterial coronariana foram associadas com obesidade. Entretanto, o polimorfismo LEP G-2548A não foi relacionado com essas variáveis. Os resultados deste estudo são sugestivos de que o polimorfismo LEP G-2548A tem papel importante na regulação da leptina plasmática e no índice de massa corporal em mulheres

    Relationship of short tandem repeats flanking leptin-melanocortin pathway genes with anthropometric profile and leptinemia in Brazilian individuals

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    Objective: To investigate the relationship of short tandem repeats (STR) near genes involved in the leptin-melanocortin pathway with body mass index (BMI) and leptinemia. Subjects and methods: Anthropometric variables and leptinemia were measured in 100 obese and 110 non-obese individuals. D1S200, D2S1788, DS11912, and D18S858 loci were analyzed by PCR and high-resolution electrophoresis. Results: Overall STR allele frequencies were similar between the obese and non-obese group (p &gt; 0.05). Individual alleles D1S200 (17), D11S912 (43), D18S858 (11/12) were associated with obesity (p &lt; 0.05). Individuals carrying these alleles showed higher BMI than non-carriers (p &lt; 0.05). Moreover, a relationship between D18S858 11/12 alleles and increased waist circumference was found (p = 0.040). On the other hand, leptinemia was not influenced by the studied STRs (p &gt; 0.05). Conclusions: D1S200, D11S912, and D18S858 loci are associated with increased BMI and risk for obesity in this sample. Arq Bras Endocrinol Metab. 2012;56(1):47-53Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP), Sao Paulo, SP, BrazilFundacao de Amparo a Pesquisa do Estado de Sao Paulo (Fapesp), Sao Paulo, SP, Brazil [01/10708-3]FapespFAPESPCNPq, BrazilCNPq (Brazil

    Relationship between variants of the leptin gene and obesity and metabolic biomarkers in Brazilian individuals Associação entre variantes do gene de leptina e obesidade e biomarcadores metabólicos em indivíduos brasileiros

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    AbstrAct Objective: The relationship between variants of the leptin gene (LEP) and obesity and metabolic biomarkers was investigated in Brazilian individuals. Subjects and methods: One-hundred-ten obese (BMI &gt; 30 kg/m 2 ) and 100 non-obese individuals (145 women and 65 men, aged 49 ± 14 years) were randomly selected. Plasma leptin, glycemia, serum lipid measurements and LEP -2548G&gt;A and 3&apos;HVR polymorphisms were analyzed. Results: The LEP -2548GG genotype was associated with a 2.2% and 2.0% increase in BMI (p = 0.009) and plasma leptin (p = 0.031), respectively. 3&apos;HVR I/II (classes I/I+I/II) genotypes contributed with 1.8% of BMI values (p = 0.046). LEP I/G combined genotypes (I/IGG, I/IGA and I/IIGG) were associated with obesity, and increased BMI, waist circumference, leptin and triglycerides (p &lt; 0.05). These relationships were found in women (p &lt; 0.05) but not in men. LEP I/G combined genotypes were not associated with hypertension, hyperglycemia, dyslipidemia and coronary artery disease. Conclusions: LEP I/G combined genotypes are associated with obesity-related metabolic biomarkers and phenotype in a gender-dependent manner. Arq Bras Endocrinol Metab. 2010;54(3):282-8 Keywords Leptin; gene polymorphism; obesity; metabolic biomarkers; plasma leptin rEsUMO Objetivo: A relação entre as variantes do gene da leptina (LEP) e obesidade e biomarcadores metabólicos foi investigada em indivíduos brasileiros. Sujeitos e métodos: Cento e dez indiví-duos obesos (IMC &gt; 30 kg/m 2 ) e 100 não obesos (145 mulheres e 65 homens, idade 49 ± 14 anos) foram selecionados aleatoriamente. Leptina plasmática, glicemia, lípides séricos e polimorfismos LEP -2548G&gt;A e 3&apos;HVR foram analisados. Resultados: O genótipo -2548GG foi associado com aumento de 2,2% e 2,0% no IMC (p = 0,009) e leptina plasmática (p = 0,031), respectivamente, enquanto os genótipos 3´HVR I/II (classes I/I+I/II) contribuíram com 1,8% dos valores de IMC (p = 0,046). Os genótipos combinados LEP I/G (I/IGG, I/IGA e I/IIGG) foram associados com obesidade e IMC aumentado, circunferência abdominal, leptina e triglicérides aumentados (p &lt; 0,05). Essas relações foram encontradas em mulheres (p &lt; 0,05), mas não em homens. Os genótipos LEP I/G combinados não foram associados com hipertensão, hiperglicemia, dislipidemia e doença arterial coronariana. Conclusões: Genótipos combinados LEP I/G são associados com biomarcadores metabólicos e fenótipo de obesidade de forma gênero-dependente. Arq Bras Endocrinol Metab. 2010;54(3):282-8 Descritores Leptina; polimorfismo genético; obesidade; biomarcadores metabólicos; leptina plasmátic

    Novel genes detected by transcriptional profiling from whole-blood cells in patients with early onset of acute coronary syndrome

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    AbstractBackgroundGenome-wide expression analysis using microarrays has been used as a research strategy to discovery new biomarkers and candidate genes for a number of diseases. We aim to find new biomarkers for the prediction of acute coronary syndrome (ACS) with a differentially expressed mRNA profiling approach using whole genomic expression analysis in a peripheral blood cell model from patients with early ACS.Methods and resultsThis study was carried out in two phases. On phase 1 a restricted clinical criteria (ACS-Ph1, n=9 and CG-Ph1, n=6) was used in order to select potential mRNA biomarkers candidates. A subsequent phase 2 study was performed using selected phase 1 markers analyzed by RT-qPCR using a larger and independent casuistic (ACS-Ph2, n=74 and CG-Ph2, n=41). A total of 549 genes were found to be differentially expressed in the first 48h after the ACS-Ph1. Technical and biological validation further confirmed that ALOX15, AREG, BCL2A1, BCL2L1, CA1, COX7B, ECHDC3, IL18R1, IRS2, KCNE1, MMP9, MYL4 and TREML4, are differentially expressed in both phases of this study.ConclusionsTranscriptomic analysis by microarray technology demonstrated differential expression during a 48h time course suggesting a potential use of some of these genes as biomarkers for very early stages of ACS, as well as for monitoring early cardiac ischemic recovery
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