Hildete Prisco Pinheiro

Sex differences in risk factors for coronary heart disease: a study in a Brazilian population

BackgroundIn Brazil coronary heart disease (CHD) constitutes the most important cause of death in both sexes in all the regions of the country and interestingly, the difference between the sexes in the CHD mortality rates is one of the smallest in the world because of high rates among women. Since a question has been raised about whether or how the incidence of several CHD risk factors differs between the sexes in Brazil the prevalence of various risk factors for CHD such as high blood cholesterol, diabetes mellitus, hypertension, obesity, sedentary lifestyle and cigarette smoking was compared between the sexes in a Brazilian population; also the relationships between blood cholesterol and the other risk factors were evaluated.ResultsThe population presented high frequencies of all the risk factors evaluated. High blood cholesterol (CHOL) and hypertension were more prevalent among women as compared to men. Hypertension, diabetes and smoking showed equal or higher prevalence in women in pre-menopausal ages as compared to men. Obesity and physical inactivity were equally prevalent in both sexes respectively in the postmenopausal age group and at all ages. CHOL was associated with BMI, sex, age, hypertension and physical inactivity.ConclusionsIn this population the high prevalence of the CHD risk factors indicated that there is an urgent need for its control; the higher or equal prevalences of several risk factors in women could in part explain the high rates of mortality from CHD in females as compared to males.

Partitioning of molecular variation at local spatial scales in the vulnerable neotropical freshwater turtle, Hydromedusa maximiliani (Testudines, Chelidae): implications for the conservation of aquatic organisms in natural hierarchical systems

Abstract Hydromedusa maximiliani is a vulnerable freshwater turtle endemic to mountainous regions of the Atlantic rainforest in southeastern Brazil. Random amplified polymorphic DNA (RAPD) were surveyed with the purpose of assessing the genetic structure and determining the partitioning of molecular variation in H. maximiliani across the natural spatial hierarchical scale of its habitat. The goal of the study was to integrate ecological data with estimates of molecular genetics diversity to develop strategies for the conservation of this freshwater turtle. Specimens were sampled from rivers and streams across three drainages. Nine of the 80 primers used generated 27 scoreable bands of which 10 (37%) were polymorphic and produced 16 RAPD phenotypes. Significant heterogeneity was found in the distribution of RAPD molecular phenotypes across the three drainages. Analysis of molecular variance for molecular phenotypes showed that the heterogeneity had a spatial structure since a significant amount (22%) of the total variance was attributable to variation among rivers and streams. Since the genetic variation of this turtle seems to be structured according to the natural hierarchical system of rivers and streams within drainages, it is suggested that local populations should be considered as separate management units.

Decomposability of high-dimensional diversity measures: Quasi-U-statistics, martingales and nonstandard asymptotics

In analyses of complex diversity, especially that arising in genetics, genomics, ecology and other high-dimensional (and sometimes low-sample-size) data models, typically subgroup decomposability (analogous to ANOVA decomposability) arises. For group divergence of diversity measures in a high-dimension low-sample-size scenario, it is shown that Hamming distance type statistics lead to a general class of quasi-U-statistics having, under the hypothesis of homogeneity, a martingale (array) property, providing a key to the study of general (nonstandard) asymptotics. Neither the stochastic independence nor homogeneity of the marginal probability laws plays a basic role. A genomic MANOVA model is presented as an illustration.

The effect of 24-epibrassinolide and clotrimazole on the adaptation of Cajanus cajan (L.) Millsp. to salinity

The objective of this study was to evaluate the effects of one of brassinosteroids (24-epibrassinolide) and clotrimazole, (an inhibitor of brassinosteroid synthesis) on plant growth parameters, parameters related to leaf gas exchange (photosynthetic and transpiration rates; stomatal conductance; water use efficiency), photosynthetic pigment content and osmolyte (sugars and proline) content in Cajanus cajan exposed to salinity. Salt stress—caused by NaCl treatment—affected values of all parameters analyzed. The effects were ameliorated by 24-epibrassinolide and intensified by clotrimazole. The hormone increased fresh mass of the plant, shoot dry mass, leaf area, water content of leaves and roots, photosynthetic pigments, sugar concentration, photosynthetic rate, and water use efficiency. The effects of hormone were less evident in the absence of salt. However, under this condition the application of clotrimazole affected the values of parameters studied, indicating the importance of brassinosteroid synthesis for the normal development of the plant.

24-epibrassinolide restores nitrogen metabolism of pigeon pea under saline stress

BackgroundSeveral studies have shown that brassinosteroids attenuate the effects of salt stress. However, nothing is known about their effects on amino acid transport, nor the effects of these hormones on nitrate uptake under saline conditions. This study set out to determine the effects of 24-epibrassinolide, at concentrations of 10-7 M and 0.5 × 10-9 M, and clotrimazole (inhibitor of brassinosteroid synthesis), at 10-4 M, on nitrate uptake and metabolism in plants of C. cajan (L.) Millsp, cultivar C11, growing under salinity. The following aspects were analyzed: levels of proteins, amino acids, nitrate, nitrate reductase of roots and the composition of xylem sap amino acids.ResultsSalinity reduced the proportion of N-transport amino acids ASN (the major component), GLU, ASP and GLN. The effect of the hormone in reducing the adverse effects of salt was related to the reestablishment (totally or partially) of the proportions of GLU, ASN and GLN, transported in the xylem and to the small but significant increase in uptake of nitrate. Increased nitrate uptake, induced by 24- epibrassinolide, was associated with a higher activity of nitrate reductase together with greater levels of free amino acids and soluble proteins in roots of plants cultivated under saline conditions.ConclusionThe decline in several components of nitrogen metabolism, induced by salt, was attenuated by 24-epibrassinolide application and accentuated by clotrimazole, indicating the importance of brassinosteroid synthesis for plants growing under salinity.

Multivariate models for correlated count data

In this study, we deal with the problem of overdispersion beyond extra zeros for a collection of counts that can be correlated. Poisson, negative binomial, zero-inflated Poisson and zero-inflated negative binomial distributions have been considered. First, we propose a multivariate count model in which all counts follow the same distribution and are correlated. Then we extend this model in a sense that correlated counts may follow different distributions. To accommodate correlation among counts, we have considered correlated random effects for each individual in the mean structure, thus inducing dependency among common observations to an individual. The method is applied to real data to investigate variation in food resources use in a species of marsupial in a locality of the Brazilian Cerrado biome.

Cholesteryl ester transfer protein gene mutations in Brazilian hyperalphalipoproteinemia

To the Editor: Cholesteryl ester transfer protein (CETP) plays a central role in high-density lipoprotein (HDL) metabolism and is a key protein in the reverse cholesterol transport (1, 2). CETP facilitates the transfer of cholesteryl ester from HDL to apolipoprotein B-containing lipoproteins, and its deficiency is associated with hyperalphalipoproteinemia (HALP) (3, 4). Although the inverse association between HDL-cholesterol (HDL-C) concentrations and cardiovascular disease (CVD) is well established (5), the role of CETP in atherosclerosis remains controversial (6–8). Several mutations at the CETP gene locus have been described, which cause depletion of CETP activity and consequently high HDL-C in plasma (4, 9). HALP patients due to plasma CETP deficiency have been reported, mostly from Japan (3, 4, 8, 10), but there are some reports of CETP deficiency from German, Caucasian, and Asian populations (9). In this study, we investigated the prevalence of the most studied CETP gene mutations (intron 14 splicing defect, Int14A, and exon 15 missense mutation, D442G) in Brazilian HALP subjects (152 HALP and 139 controls, CTL). In addition, we evaluated the impact of each genetic mutation on the degree of carotid atherosclerosis, the concentrations of lipoproteins, the activities of CETP, phospholipid transfer protein (PLTP), and lipases in the plasma. For the identification of the CETP mutations, the genomic DNAs were extracted from peripheral leukocytes and analyzed by the polymerase chain reaction-restriction fragment length polymorphism method, as described previously (11–13). The Brazilian population is ethnically diverse, with a predominance of Afro-descendents. The frequency of the Int14A and D442G alleles in the HALP population was 0.023 and 0.0033, respectively. The prevalence of Int14A mutation was 4%, which was lower than that observed in the Japanese HALP population (32%) (14) but higher than that in the North-American HALP (0.7%) (9) and Japanese-American HALP (0.5%) subjects (6). The prevalence of the D442G mutation was far lower (0.7%) than that reported for the HALP (above 22%) and Japanese general population (4.5–7%) (4, 12) and for JapaneseAmerican subjects (5.1%) (6). Among the six Int14A mutation carriers (Table 1), we found one homozygote, a 61-yearold white woman, born from a non-consanguineous marriage, with family history of coronary artery disease (CAD), but no clinical cardiovascular damage. This is the first description of a homozygote Int14A CETP mutation outside Japan. Among the heterozygotes for Int14A, a 29-year-old male presented corneal arcus with established CAD and a 46-year-old female presented a carotid atheroma with no other manifestations of CVD. Both were whites, with no biochemical characteristics distinct from other mutation carriers. Three individuals had positive family histories of CAD. A 73-year-old male, from Asian origin and heterozygote for the D442G, presented results similar to the CTL group. Besides no personal or family register of CAD, he was the only one who presented increased intima-media thickness (IMT), possibly because he was the oldest. When we considered all mutation carriers together, higher HDL-C concentration (83%), lipoprotein lipase (LPL, 11%) and PLTP (60%) and lower CETP (36%) and hepatic lipase (HL, 26%) activities were observed. While the D442G carrier presented CETP, LPL, HL, and PLTP activities closer to the values from CTL group, the homozygote for Int14A mutation had an HL activity below the reference interval (2.5 and 97.5 percentiles of CTL), suggesting a double gene defect as described by Hirano et al. (7). The double deficiency of CETP and HL is Clin Genet 2006: 69: 455–457 # 2006 The Authors Printed in Singapore. All rights reserved Journal compilation # 2006 Blackwell Munksgaard

An asymptotically normal test for the selective neutrality hypothesis

An important parameter in the study of population evolution is

Power of the likelihood ratio test for models of DNA base substitution

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Homogeneity tests among groups for microsatellite data

, where