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Papers by Roberto SA

International Biodeterioration & Biodegradation, 2009

Myracrodruon urundeuva heartwood is resistant to biodeterioration and lectin purified from heartw... more Myracrodruon urundeuva heartwood is resistant to biodeterioration and lectin purified from heartwood showed antifungal and termiticidal activities. This report deals with antioxidant, antifungal and termite repellent activities of secondary metabolites from M. urundeuva heartwood. Saline (SE, active hemagglutinin preparation) and methanolic (ME, without hemagglutinating activity) extracts contain phenolic compounds, gallic acid, flavonoids, luteolin, cinamic derivatives, proanthocyanidins, hydrolysable tannins, and leucoanthocyanidins. Both SE and ME showed antioxidant activity and were effective in Fusarium growth inhibition. SE was efficient against Fusarium decemcellulare, Fusarium moniliforme, Fusarium oxysporum, and Fusarium solani but it had little effect against Fusarium lateritium. ME practically had no effect on F. decemcellulare and was more active than SE against F. lateritium. SE induced mortality of Nasutitermes corniger (LC 50 of 1.81 mg ml À1 for soldiers and 2.59 mg ml À1 for workers) and had no repellent activity. ME had no termiticidal activity but was a good repellent. The detected bioactivities point out the possibility of participation of secondary metabolites in the resistance of M. urundeuva heartwood to biodeterioration. Additionally, the results indicate the use of wood residues, as extracts, a source of natural bioactive agents.

Revista De Saude Publica, 2003

OBJETIVO: Avaliar o consumo de sal e a relação sódio/potássio urinário em amostra randomizada de ... more OBJETIVO: Avaliar o consumo de sal e a relação sódio/potássio urinário em amostra randomizada de população urbana etnicamente miscigenada. MÉTODOS: Foi selecionada uma amostra randômica de 2.268 residentes de Vitória, ES, entre 25 e 64 anos de idade. Os indivíduos foram escolhidos por amostragem domiciliar realizada em 1999/2000, dos quais 1.663 (73,3%) compareceram ao hospital para a realização de exames padronizados. O consumo estimado de sal, Na+ e K+ foi determinado por meio da coleta de urina de 12h no período noturno (19h às 7h) e do gasto mensal de sal domiciliar referido durante a entrevista. A pressão arterial clínica foi medida duas vezes por diferentes pesquisadores treinados em condições padronizadas, usando esfignomamômetro de mercúrio. Para análise estatística foram utilizados o teste de Student e o teste de Tukey. RESULTADOS: A excreção urinária de Na+ foi mais alta em homens e em indivíduos de menores condições socioeconômicas (P<0,000). Não foi observada diferença entre os grupos étnicos. A excreção de K+ não se relacionou com nível socioeconômico e raça, mas foi significativamente mais alta entre os homens (25±18 x 22±18 mEq/12h; P=0,002). Foi observada uma correlação linear positiva entre a excreção urinária de Na+ e pressão arterial sistólica (r=0,15) e diastólica (r=0,19). Indivíduos hipertensos apresentaram maior excreção urinária de Na+ e relação Na/K, quando comparados com indivíduos normotensos. O consumo de sal relatado foi aproximadamente 50% do consumo estimado pela excreção urinária de 12h (em torno de 45% da excreção urinária de 24h). CONCLUSÕES: A ingestão de sal é fortemente influenciada pelo nível socioeconômico e pode, parcialmente, explicar a alta prevalência de hipertensão arterial nas classes socioeconômicas mais baixas.

International Biodeterioration & Biodegradation, 2011

... Colonies of N. corniger, identified by Dr. Luiz Roberto Fontes (Superintendência de Controle ... more ... Colonies of N. corniger, identified by Dr. Luiz Roberto Fontes (Superintendência de Controle de Endemias, SUCEN, Brazil), were kept in a vegetation house at the agronomy department of the Universidade Federal Rural de Pernambuco. ...

Wood Science and Technology, 2009

The aim of this work was to isolate a lectin from Myracrodruon urundeuva heartwood and to evaluat... more The aim of this work was to isolate a lectin from Myracrodruon urundeuva heartwood and to evaluate its antimicrobial activity against bacteria and fungi that attack plants, including woods. The lectin was isolated from heartwood through affinity chromatography on a chitin column monitored by hemagglutination assay. The lectin inhibited Gram-negative and Gram-positive bacteria and was more effective than antifungal Cercobin in growth inhibition of phytopathogenic fungi. The detected antimicrobial activity reveals the possible role of the lectin in the resistance of M. urundeuva heartwood against deteriorative biological agents. The M. urundeuva lectin is the first bioactive peptide found in heartwood, probably stored as a chemical protection against biodegradation.

Saude E Sociedade, 2010

This paper presents a detailed discussion about the convergence properties of a variable structur... more This paper presents a detailed discussion about the convergence properties of a variable structure controller for uncertain single-input-single-output nonlinear systems (SISO). The adopted approach is based on the sliding mode control strategy and enhanced by an adaptive fuzzy algorithm to cope with modeling inaccuracies and external disturbances that can arise. The boundedness of all closed-loop signals and the convergence properties of the tracking error are analytically proven using Lyapunov's direct method and Barbalat's lemma. This result corrects flawed conclusions previously reached in the literature. An application of this adaptive fuzzy sliding mode controller to a second-order nonlinear system is also presented. The obtained numerical results demonstrate the improved control system performance.

Journal of The American College of Cardiology, 1995

Objectives. We attempted to establish a relation between the atrial conduction time assessed by t... more Objectives. We attempted to establish a relation between the atrial conduction time assessed by the signal-averaged P wave electrocardiogram and episodes of paroxysmal atrial fibrillation in patients with the Wolff.Parkinson-White syndrome.

Lipids in Health and Disease, 2010

Background: Cardiovascular diseases (CVD) are the main cause of death and disability in developed... more Background: Cardiovascular diseases (CVD) are the main cause of death and disability in developed countries. In most cases, the progress of CVD is influenced by environmental factors and multifactorial inheritance. The purpose of this study was to investigate the association between APOE genotypes, cardiovascular risk factors, and a noninvasive measure of arterial stiffness in the Brazilian population. Methods: A total of 1493 urban Brazilian individuals were randomly selected from the general population of the Vitoria City Metropolitan area. Genetic analysis of the APOE polymorphism was conducted by PCR-RFLP and pulse wave velocity analyzed with a noninvasive automatic device.

Transplantation Proceedings, 2007

Livers from marginal donors are increasingly used for transplantation due to the shortage of dono... more Livers from marginal donors are increasingly used for transplantation due to the shortage of donor organs. The definition of a marginal donor remains unclear; prediction of organ function is a challenge. In the literature the use of steatotic livers has been associated with poor liver function or even primary dysfunction of the allograft. Tekin et al created a scoring system that classifies a donor as marginal or nonmarginal, using a mathematical model based on donor age and steatosis degree. The aims of this study were to apply the Tekin method to identify marginal and nonmarginal donors and evaluate the influence of the cold ischemia time (CIT) on allograft evolution. We retrospectively reviewed deceased donor liver transplantations performed from October 1995 to March 2006, namely, 177 adult liver transplantations in 163 patients. Fifty-five were excluded due to retransplantation (14) or insufficient data (41). Donor age and macrovesicular steatosis were evaluated according to the mathematical formula proposed by Tekin et al, classifying the donors as marginal versus nonmarginal. The authors also analyzed the CIT, 3-month mortality, and development of primary nonfunction or primary dysfunction. The median donor age was 38.9 years (range, 6–71). The postreperfusion biopsy specimen showed moderate to intense steatosis (>30%) in 14.75% of specimens, with no steatosis or mild steatosis in 85.25%. Sixty-one grafts (50%) developed primary graft dysfunction (PGD): 10 grafts, with primary nonfunction (PNF); and 51 with initial poor function (IPF). Using the criteria provided by Tekin et al, we obtained 41 marginal and 81 nonmarginal allografts. The marginal group showed 61.9% PGD, compared with 59.2% of PGD by the nonmarginal group. The CIT was greater than 12 hours in 5 marginal group transplants and 4 PGD cases (80%). Of the nonmarginal allografts, the CIT was greater than 12 hours in 29.6%, with 75% PGD. The 3-month graft survival rate was 80% in the marginal group with ischemia time more than 12 hours: 86.1% of the same group when CIT was less than 12 hours, and 82.7% in the nonmarginal group. In contrast, when we analyzed the occurrance of allograft dysfunction, the 3-month mortality rate was 34% among, grafts with dysfunction, whereas, in those without initial dysfunction, it was 4.1%. In conclusion, the score suggested by Tekin et al that classifies the donors as ideal (nonmarginal) or marginal was not able to predict initial primary dysfunction.

Journal of Hypertension, 2009

Objective Cardiovascular risk factors were surveyed in two Indian populations (Guarani, n U 60; T... more Objective Cardiovascular risk factors were surveyed in two Indian populations (Guarani, n U 60; Tupinikin, n U 496) and in a non-Indian group (n U 114) living in the same reserve in southeast Brazilian coast. The relationship between an agedependent blood pressure (BP) increase with salt consumption was also investigated.

Arquivos Brasileiros De Cardiologia, 2000

Objective -To determine in arrhythmogenic right ventricular cardiomyopathy the value of QT interv... more Objective -To determine in arrhythmogenic right ventricular cardiomyopathy the value of QT interval dispersion for identifying the induction of sustained ventricular tachycardia in the electrophysiological study or the risk of sudden cardiac death.

Arquivos Brasileiros De Cardiologia, 2002

As diretrizes para o diagnóstico e tratamento das arritmias cardíacas surgiram a partir da filoso... more As diretrizes para o diagnóstico e tratamento das arritmias cardíacas surgiram a partir da filosofia da Sociedade Brasileira de Cardiologia (SBC) de manter atualizadas as informações de procedimentos relacionados ao diagnóstico e tratamento de pacientes com cardiopatias.

Drugs, 1988

The choice of an appropriate antihypertensive agent and the hazards of postural hypotension are c... more The choice of an appropriate antihypertensive agent and the hazards of postural hypotension are common problems faced in the treatment of diabetic hypertensive patients. The results of 3 studies addressing these problems are described in this report. In the first study, indoramin, an alpha-blocking agent, was administered to patients with non-insulin-dependent diabetes and mild to moderate hypertension. Blood pressure control was achieved in 57% of patients with mild, and in none with moderate hypertension. The blood glucose and insulin responses to an oral 50g glucose loading, as well as the blood concentrations of HbA1 did not change during therapy. Seven patients were excluded because of side effects. In 4 of them postural hypotension was observed. In the second study, the effects of angiotensin-converting enzyme (ACE) inhibitors, administered to patients with non-insulin-dependent diabetes and mild to moderate hypertension, were evaluated. Blood pressure control was achieved in 78% of the patients on captopril (n = 14) and in 74% of patients on enalapril therapy (n = 23). Symptomatic postural hypotension (n = 2) and hyperkalaemia (n = 2) were observed with both drugs. Significant reductions in 24-hour urinary protein or albumin excretion were detected in 12 patients on enalapril therapy. No changes in 2-hour postprandial blood glucose and HbA1 levels were observed during therapy with ACE inhibitors. In the third study, dopaminergic antagonist agents were evaluated in diabetic patients with orthostatic hypotension. In 7 patients metoclopramide (20mg intravenously) reduced the fall in mean arterial pressure induced by upright tilt.(ABSTRACT TRUNCATED AT 250 WORDS)

International Biodeterioration & Biodegradation, 2008

... Table 1. Summary of lectin isolation from M. urundeuva heartwood Sample, Total protein (mg), ... more ... Table 1. Summary of lectin isolation from M. urundeuva heartwood Sample, Total protein (mg), HA (titer −1 ), SHA, Purification (times). Extract, 952, 32,768, 2409, 1.0. 4060F, 146, 32,768, 3181, 1.3. ... SHA (specific HA) was calculated from the ratio of titer to protein concentration (mg ...

Hypertension Research, 2009

The objective of this study was to investigate the association between sodium intake and metaboli... more The objective of this study was to investigate the association between sodium intake and metabolic syndrome (MS) in individuals free from the confounding effects of increased blood pressure (BP). In all, a total of 1655 individuals (45.8% men) who participated in the MONICA-WHO/Vitoria Project, mean age 45±11 years were investigated. According to NCEP-ATP lll criteria, MS prevalence was 32.9 and 85% of these individuals had BP 4130/85 mm Hg. Thus, high BP represents the main MS risk factor. Twelve-hour nocturnal urine (1900 to 0700 hours) was used to measure urinary sodium and potassium excretion. Sodium excretion was associated with BP. From the optimal BP level up to stage lll hypertension, the mean (median) sodium excretion increased from 99 (89) to 128 (134) mEq and from 81 (69) to 112 (103) mEq in men and women, respectively (Po0.001 for trend; median). However, when 781 individuals with BP o130/85 mm Hg (including 80 drug-free normotensive individuals with MS) were stratified according to the gender and number of MS components, no significant differences were observed either in the urinary volume or in the sodium or potassium excretion. For each of the four MS components, sodium excretion was 96 ± 48, 97 ± 53, 108 ± 65 and 97 ± 49 mEq for men, and 83 ± 51, 83 ± 58, 80 ± 49 and 93 ± 45 mEq for women, respectively. No differences were found in urinary sodium excretion in normotensive individuals, regardless of the presence of MS. Therefore, it seems that high sodium intake is not an MS predictor per se as suggested earlier.

Comparative Biochemistry and Physiology C-toxicology & Pharmacology, 2009

Aedes aegypti transmits etiologic agents of yellow fever and dengue. Vaccine for dengue virus is ... more Aedes aegypti transmits etiologic agents of yellow fever and dengue. Vaccine for dengue virus is not available and vector control is essential to minimize dengue incidence. This report deals with the larvicidal activity of lectins isolated from Myracrodruon urundeuva bark (MuBL) and heartwood (MuHL). The lectins were isolated by ammonium sulphate treatment of crude extracts followed by chromatography on chitin. MuBL and MuHL were evaluated by electrophoresis under native (PAGE) and denaturing conditions (SDS-PAGE). Carbohydrate specificity of lectins was evaluated by hemagglutinating activity (HA) inhibition assay using N-acetyl-Dglucosamine and by affinity chromatography on N-acetyl-D-glucosamine immobilized in agarose gel. Larvicidal activity against A. aegypti was investigated with the extracts, salt fractions and isolated lectins. MuBL and MuHL were characterized by PAGE as basic proteins of molecular masses of 14.0 and 14.4 kDa, respectively. The interaction of lectins with N-acetylglucosamine was detected by inhibition of HA by monosaccharide and lectin adsorptions on N-acetyl-D-glucosamine matrix. All M. urundeuva preparations promoted larvae mortality. LC 16 , LC 50 and LC 84 values of 0.077, 0.125, 0.173 for MuBL and 0.03, 0.04 and 0.05 mg/mL for MuHL were obtained. To our knowledge this is the first report of larvicidal activity of lectins against A. aegypti.

Arquivos Brasileiros De Cardiologia, 2004

Atherosclerosis, 2006

We investigated the association of endothelial nitric oxide synthase ( NOS3 ) polymorphisms rs207... more We investigated the association of endothelial nitric oxide synthase ( NOS3 ) polymorphisms rs2070744 ( -786T Ͼ C), 27-bp repeat 4b/4a, rs1799983 (Glu298Asp), rs3918188 ( -734C Ͼ A), and rs743507 (113G Ͼ A) with idiopathic recurrent miscarriage (IRM). This was a case-control study involving women with confi rmed IRM (n ϭ 296), and 305 age-and ethnically matched control women. NOS3 rs2070744, rs1799983, rs3918188, and rs743507 genotyping was done by TaqMan assays; NOS3 4b/4a genotyping was done by PCR-ASA. A higher frequency of -786C and 298Asp alleles was seen in IRM cases, which remained associated independently with IRM on multivariate analysis. Allele and genotype distribution of 4b/4a, rs3918188 ( -734C Ͼ A) and rs743507 (113A Ͼ G) were comparable between IRM cases and control women. Taking homozygous wild-type genotype as a reference, regression analysis confi rmed the association of Glu298Asp and -786T/C, and rs743507 homozygous carriers with IRM risk. Marked linkage disequilibrium was seen between tested NOS3 variants, thus allowing the construction of 5-locus [ -786T Ͼ C/4b4a/Glu298Asp/-734C Ͼ A/113G Ͼ A] haplotypes. Taking the common T4 b GCA haplotype as a reference, multivariate analysis confi rmed the positive association of C4 b TCG haplotype with IRM, after controlling for traditional covariates. Genetic variation at the NOS3 locus represents a genetic risk factor for increased susceptibility to IRM.

American Journal of Physiology-heart and Circulatory Physiology, 2005

In spontaneously hypertensive rats (SHR), carotid and aortic distensibility measured at operation... more In spontaneously hypertensive rats (SHR), carotid and aortic distensibility measured at operational blood pressure (BP) is reduced. Increased body weight and mean arterial pressure (MAP) are known both to reduce independently distensibility. However, whether, after adjustment to body weight and mean BP, distensibility remains reduced in SHR has never been investigated. Carotid and abdominal aorta distensibility was measured under anesthesia in SHR at 5, 12, 52 and 78 weeks of age and compared with age-matched normotensive Wistar rats.