Heritability of physical activity traits in Brazilian families: the Baependi Heart Study

Background It is commonly recognized that physical activity has familial aggregation; however, the genetic influences on physical activity phenotypes are not well characterized. This study aimed to (1) estimate the heritability of physical activity traits in Brazilian families; and (2) investigate whether genetic and environmental variance components contribute differently to the expression of these phenotypes in males and females. Methods The sample that constitutes the Baependi Heart Study is comprised of 1,693 individuals in 95 Brazilian families. The phenotypes were self-reported in a questionnaire based on the WHO-MONICA instrument. Variance component approaches, implemented in the SOLAR (Sequential Oligogenic Linkage Analysis Routines) computer package, were applied to estimate the heritability and to evaluate the heterogeneity of variance components by gender on the studied phenotypes. Results The heritability estimates were intermediate (35%) for weekly physical activity among non-sedentary subjects (weekly PA_NS), and low (9-14%) for sedentarism, weekly physical activity (weekly PA), and level of daily physical activity (daily PA). Significant evidence for heterogeneity in variance components by gender was observed for the sedentarism and weekly PA phenotypes. No significant gender differences in genetic or environmental variance components were observed for the weekly PA_NS trait. The daily PA phenotype was predominantly influenced by environmental factors, with larger effects in males than in females. Conclusions Heritability estimates for physical activity phenotypes in this sample of the Brazilian population were significant in both males and females, and varied from low to intermediate magnitude. Significant evidence for heterogeneity in variance components by gender was observed. These data add to the knowledge of the physical activity traits in the Brazilian study population, and are concordant with the notion of significant biological determination in active behavior.

Antihypertensive and antioxidant effects of a single daily dose of sodium nitrite in a model of renovascular hypertension

Dietary nitrite and nitrate have been reported as alternative sources of nitric oxide (NO). In this regard, we reported previously that sodium nitrite added to drinking water was able to exert antihypertensive effects in an experimental model of hypertension in a dose-dependent manner. Taking into consideration that nitrite is continuously converted to nitrate in the bloodstream, here we expanded our previous report and evaluate whether a single daily dose of sodium nitrite could exert antihypertensive effects in 2 kidney-1 clip (2K1C) hypertensive rats. Sham-operated and 2K1C rats were treated with vehicle or sodium nitrite (15 mg/kg/day) for 4 weeks. We evaluated the effects induced by sodium nitrite treatment on systolic blood pressure (SBP) and NO markers such as plasma nitrite, nitrite + nitrate (NOx), cGMP, and blood levels of nitrosyl-hemoglobin. In addition, we also evaluated effects of nitrite on oxidative stress and antioxidant enzymes. Dihydroethidium (DHE) was used to evaluate aortic reactive oxygen species (ROS) production by fluorescence microscopy, and plasma levels of thiobarbituric acid-reactive species (TBARS) were measured in plasma samples from all experimental groups. Red blood cell superoxide dismutase (SOD) and catalase activity were evaluated with commercial kits. Sodium nitrite treatment reduced SBP in 2K1C rats (P < 0.05). We found lower plasma nitrite and NOx levels in 2K1C rats compared with normotensive controls (both P < 0.05). Nitrite treatment restored the lower levels of nitrite and NOx. While no change was found in the blood levels of nitrosyl-hemoglobin (P > 0.05), nitrite treatment increased the plasma levels of cGMP in 2K1C rats (P < 0.05). Higher plasma TBARS levels and aortic ROS levels were found in hypertensive rats compared with controls (P < 0.05), and nitrite blunted these alterations. Lower SOD and catalase activities were found in 2K1C hypertensive rats compared with controls (both P < 0.05). Nitrite treatment restored SOD activity (P < 0.05), whereas catalase was not affected. These data suggest that even a single daily oral dose of sodium nitrite is able to lower SBP and exert antioxidant effects in renovascular hypertension.

The red-billed curassow (Crax blumenbachii): social organization, and daily activity patterns

We studied the Red-billed Currasow (Cray blumenbachii) in Vale Natural Reserve, Linhares, Espirito Santo State, Brazil, using camera traps. We found the Red-billed Curassow present in the entire area of the reserve (similar to 22,000 ha) during 40 months of camera trapping (2005-2008). Most records were of single individuals, especially males, but pairs and even groups of individuals were also recorded. Males were paired with one and two females, suggesting polygyny in the species. The species was recorded throughout the day with one peak from 0500 to 0600 hrs and another after 1600 hrs. The daily activity pattern was similar for males and females. The number and widespread nature of the records suggests the local population of this species may be higher than previously thought. Received 10 March 2011. Accepted 5 December 2011.

Physical Activity In Daily Life In Brazilian COPD Patients During and After Exacerbation

Background: Although hospitalization is recognized as an important cause of reduction in physical activity in daily life (PADL) in COPD, there is only one study evaluating this effect, and it was performed in European COPD patients who have a lower PADL than that of South American COPD patients. Objectives: To investigate the effect of hospitalization due to acute exacerbation of PADL in Brazilian COPD patients and to evaluate the factors that determines the physical activity levels during hospitalization and after discharge. Methods: PADL was quantified using a 3-axis accelerometer on the 3rd day of hospitalization and 1 month after discharge in Brazilian COPD patients who were hospitalized due to disease exacerbation. Six-minute walking distance (6MWD), lower limb strength and pulmonary function were also evaluated. Results: A total of 20 patients completed the study. During hospitalization, patients spent most of the time (87%) lying down or sitting; however, 1 month after they were walking >40 min/day. In addition, patients with prior hospitalization had a lower level of physical activity compared to those without a previous history of hospitalization. The time spent walking during hospitalization was significantly explained by the quadriceps strength (r(2) = 0.29; p < 0.05), while 1 month after, the time spent walking was only significantly explained by the 6MWD (r(2) = 0.51; p = 0.02). Conclusions: Brazilian COPD patients are inactive during hospitalization but become active 1 month after discharge. Previously hospitalized are more inactive both during and after exacerbation. The quadriceps strength and 6MWD explain the physical activity levels during hospitalization and at home, respectively.

High Prevalence of Dementia in a Community-Based Survey of Older People from Brazil: Association with Intellectual Activity Rather than Education

Although several surveys have been conducted around the world, few surveys have investigated the prevalence of dementia in Latin America. The aim of this study was to estimate dementia prevalence in a community sample in Ribeirao Preto, Brazil, and to evaluate its distribution across several socio-demographic and clinical characteristics and habits. The population was aged 60 years and older and a representative sample from three different social regions. The screening instruments used in the first phase were the Mini-Mental State Examination, the Fuld Object-Memory Evaluation, the Informant Questionnaire on Cognitive Decline in the Elderly, and the Bayer Activities of Daily Living Scale. In the second phase, the Cambridge Examination was employed to diagnose dementia according to the DSM-IV criteria. The estimate of dementia prevalence was adjusted for screening instrument performance, using the positive and negative predictive values. The data were weighted to compare frequencies, considering the sampling and the non-response effect, and subjected to multivariate analysis. In all, 1.145 elderly subjects were evaluated (mean age: 70.9 years), of whom 63.4% were female and 52.8% had up to 4 years of schooling (participation rates at the first and the second phases were 62.6 and 60%, respectively). The observed and estimated prevalences of dementia were 5.9% and 12.5%, respectively (n = 68). Alzheimer's disease was the main cause (60.3%). Dementia was associated with old age, low education, stroke, absence of arthritis, and not reading books. The estimated prevalence of dementia was higher than the prevalence previously found. Associated factors confirmed the importance of intellectual activities in prevention.

An integrated approach to evaluate emerging contaminants in drinking water

The chemical stock of emerging contaminants in Brazilian drinking water is of great interest due to the poor water quality at surface water intakes. In addition, little is known about the effect of some contaminants, such as endocrine disrupting chemicals (EDCs), which may be present in both raw and treated water. The aim of this work was to evaluate selected emerging contaminants in Brazilian waters using both chemical and biological analyses. Sampling sites were established in different municipalities based upon raw water quality data. Estrone, 17 beta-estradiol, estriol, 17 alpha-ethinylestradiol, bisphenol A, 4-n-octylphenol and 4-n-nonylphenol were determined in the samples by liquid chromatography-tandem mass spectrometry. A yeast assay using a Saccharomyces cerevisiae bioluminescent bioreporter was used to evaluate the estrogenic activity of the water samples. The first integrated results revealed similarities between the two individual approaches, since higher values for the bioassay were accompanied by significant concentrations of some selected compounds in surface water samples. No estrogenicity was observed for drinking water samples. Our results also indicate that the usual paradigm of evaluating water quality by measuring selected EDCs in a given water sample via chemical analysis, needs to be reviewed since the observed estrogenicity of a water sample is now a better guiding parameter to the selection of samples and substances to be chemically investigated in further analysis. So far, the data bank produced in this work, i.e., the comparison between chemical burden and observed estrogenicity, is not yet sufficiently robust to fully guide this decision. (C) 2011 Elsevier B.V. All rights reserved.

Administration of a murine diet supplemented with conjugated linoleic acid increases the expression and activity of hepatic uncoupling proteins

Daily intake of conjugated linoleic acid (CLA) has been shown to reduce body fat accumulation and to increase body metabolism; this latter effect has been often associated with the up-regulation of uncoupling proteins (UCPs). Here we addressed the effects of a CLA-supplemented murine diet (similar to 2 % CLA mixture, cis-9, trans-10 and trans-10, cis-12 isomers; 45 % of each isomer on alternating days) on mitochondrial energetics, UCP2 expression/activity in the liver and other associated morphological and functional parameters, in C57BL/6 mice. Diet supplementation with CLA reduced both lipid accumulation in adipose tissues and triacylglycerol plasma levels, but did not augment hepatic lipid storage. Livers of mice fed a diet supplemented with CLA showed high UCP2 mRNA levels and the isolated hepatic mitochondria showed indications of UCP activity: in the presence of guanosine diphosphate, the higher stimulation of respiration promoted by linoleic acid in mitochondria from the CLA mice was almost completely reduced to the level of the stimulation from the control mice. Despite the increased generation of reactive oxygen species through oxi-reduction reactions involving NAD(+)/NADH in the Krebs cycle, no oxidative stress was observed in the liver. In addition, in the absence of free fatty acids, basal respiration rates and the phosphorylating efficiency of mitochondria were preserved. These results indicate a beneficial and secure dose of CLA for diet supplementation in mice, which induces UCP2 overexpression and UCP activity in mitochondria while preserving the lipid composition and redox state of the liver.

AEROBIC OR RESISTANCE EXERCISE IMPROVES PERFORMANCE IN ACTIVITIES OF DAILY LIVING IN ELDERLY WOMEN

The purpose of this randomized non-controlled study was to determine the effect of an aerobic or resistance exercise protocol on performance of activities of daily living in elderly women. The sample was constituted of 41 apparently healthy elderly women aged 60 to 85 years (x: 65.1 +/- 7.9 years) randomly assigned in resistance exercise (n: 22) or aerobic groups (n: 19). The resistance exercise protocol consisted of three sets of eight to 12 repetitions at 60% of one repetition maximum test for the leg press 45 degrees. The aerobic exercise protocol consisted in cycling in a cycle ergometer during 40 minutes at 60% of reserve heart rate. Both protocols were performed three times per week during five weeks. Activities of daily living were estimated by velocity to stand from sitting to standing position (VSitting), velocity to move from supine to standing position (VSupine), velocity to climb stairs (VCS) and velocity to wear sneakers (VWS). Volunteers of aerobic exercise protocol improved significantly the time to perform VWS (19.1%), while the volunteers of resistance exercise protocol improved the capacity to perform VCS (4.3%) and VSupine (8.9%). These results let us conclude that aerobic as well as resistance exercise protocols induced positive effect on activities of daily living, suggesting that both protocols must be associated for an adequate exercise program to improve the functional capacity of elderly people.

Daily rhythms of native Brazilians in summer and winter

Access to electricity, granting relative independence of human activity on the dark phase of the day, has been pointed out as an important cause for the absence of seasonal changes in the daily rhythms of humans living in urban areas. Featuring a population of adult Guarani natives living without access to electricity, the present naturalistic study was designed to explore possible effects of different natural photoperiods and temperature on human circadian rhythms. We compared time series of wrist temperature (WT) and motor activity in winter and summer, respectively, 01 24 individuals aged 18 to 80. Twenty-four-hour rhythms of WT showed lower amplitudes and higher mean levels in summer, with no significant seasonal differences in acrophase. In contrast, rest-activity (RA) rhythms exhibited a significantly later rest on-and offset in summer, but no seasonal changes in duration, amplitude and mean level. We furthermore identified a phase advance of both the WT acrophase and rest onset with increasing age of the individuals. We concluded that in our study the effect of different seasons was reflected in the amplitude and mean level of the WT rhythm, as well the onset of nighttime rest, which was delayed in summer. (C) 2011 Elsevier Inc. All rights reserved.

Daily rhythm of salivary IL-1 beta, cortisol and melatonin in day and night workers

Shiftwork-induced sleep deprivation and circadian disruption probably leads to an increase in the production of cytokines and dysregulation of innate immune system, respectively. This project aims evaluating changes in salivary IL-1 beta, cortisol, and melatonin in night workers. Method. Two day and three night healthy workers participated in this study. Sleep was evaluated by actimetry and activity protocols. Saliva was collected at waking and bedtime the last workday and the following two days-off and was analyzed by ELISA. Results. Neither sleep duration nor efficiency showed any association with salivary IL-1beta. IL-1beta levels were higher at waking than at bedtime during working days for all workers, but only one day and one night-worker maintained this pattern and hormone rhythms during days off. For this night worker, melatonin levels were shifted to daytime. A second one presented clear alterations in IL-1beta and hormone rhythms on days-off. Conclusions. Our preliminary results suggest that night work can disturb the variation pattern of salivary IL-1beta. No association of this variation with sleep was observed. It seems that disruption in hormone rhythms interfere with salivary IL-1beta production. IL-1beta production pattern seems to be maintained when rhythms are present, in spite of a shift in melatonin secretion.

Field and Laboratory Studies Provide Insights into the Meaning of Day-Time Activity in a Subterranean Rodent (Ctenomys aff. knighti), the Tuco-Tuco

South American subterranean rodents (Ctenomys aff. knighti), commonly known as tuco-tucos, display nocturnal, wheel-running behavior under light-dark (LD) conditions, and free-running periods >24 h in constant darkness (DD). However, several reports in the field suggested that a substantial amount of activity occurs during daylight hours, leading us to question whether circadian entrainment in the laboratory accurately reflects behavior in natural conditions. We compared circadian patterns of locomotor activity in DD of animals previously entrained to full laboratory LD cycles (LD12:12) with those of animals that were trapped directly from the field. In both cases, activity onsets in DD immediately reflected the previous dark onset or sundown. Furthermore, freerunning periods upon release into DD were close to 24 h indicating aftereffects of prior entrainment, similarly in both conditions. No difference was detected in the phase of activity measured with and without access to a running wheel. However, when individuals were observed continuously during daylight hours in a semi-natural enclosure, they emerged above-ground on a daily basis. These day-time activities consisted of foraging and burrow maintenance, suggesting that the designation of this species as nocturnal might be inaccurate in the field. Our study of a solitary subterranean species suggests that the circadian clock is entrained similarly under field and laboratory conditions and that day-time activity expressed only in the field is required for foraging and may not be time-dictated by the circadian pacemaker.

Activity, movement and secretive behavior of a threatened arboreal folivore, the thin-spined porcupine, in the Atlantic forest of southern Bahia, Brazil

Activity and behavior patterns are important components of a given species ecological strategy, as they have profound implications for its survival and reproduction. Here, we studied the activities, movements and secretive behavior of the thin-spined porcupine Chaetomys subspinosus (Rodentia: Erethizontidae), a threatened arboreal folivore in the Brazilian Atlantic rainforest. We aimed to ascertain the behavioral strategies used by this species as well as its responses to seasonal and daily climatic changes. Four radio-collared individuals were followed continuously for 72-h in the summer and winter, as well as during 146 half-night sessions conducted from April 2005 to September 2006 in forest remnants in southern Bahia. The thin-spined porcupines were nocturnally active (17:30-05:40 h), with peaks in activity and movement from 19:00 to 20:00 h and 03:00 to 04:00 h. Animals followed a circadian rhythm of activity during both the summer and winter. During the diel cycle, porcupines spent 74% of their time resting, 14% feeding, 11% traveling and 2% performing other activities. Distance traveled during the diel cycle averaged 277.5 +/- 117.9 m sd. The mean movement rate during the night was 21.6 +/- 30.1 m/h sd. No significant changes in activity budget or daily distance traveled were observed between seasons, most likely in response to the low fluctuations in climatic conditions and food availability throughout the year in the study region. However, rainfall reduced the time that the animals spent on feeding activities and explained day-to-day differences in activity budgets. We also provide details about intraspecific interactions and defecation behavior. Our observations confirmed that thin-spined porcupines, similar to other folivorous species, present low activity levels and short daily movements, and have adopted various cryptic habits, such as nocturnality, a solitary lifestyle, the tendency to leave offspring alone most of the time and defecation in concealed latrines.

Brazilian nut consumption improves selenium status and glutathione peroxidase activity and reduces atherogenic risk in obese women

Studies have shown that there are inverse relationships between nut consumption and the reduction of cardiovascular risk. This study tested the hypothesis that daily consumption of Brazilian nuts would have a positive effect upon selenium (Se) status, erythrocyte glutathione peroxidase activity, lipid profile, and atherogenic risk in severely obese women. Thirty-seven severely obese women each consumed 1 Brazilian nut a day (290 mu g of Se a day) for 8 weeks. Blood Se concentrations, total erythrocyte glutathione peroxidase activity, lipid profile, and Castelli I and H indexes were evaluated before and after the nuts consumption. All the patients were Se deficient at baseline; this deficiency was remedied by the consumption of the Brazilian nut (P < .0001). The intake of Brazilian nuts promoted a significant increase in high-density lipoprotein cholesterol concentrations (P < .00001), which then resulted in a significant improvement of the Castelli I (P < .0002) and II (P < .0004) indexes. This study shows that obese people who implement daily consumption of Brazilian nuts can improve both Se status and lipid profile, especially high-density lipoprotein cholesterol levels, thereby reducing cardiovascular risks. (C) 2012 Published by Elsevier Inc.

Low dynamic muscle strength and its associations with fatigue, functional performance, and quality of life in premenopausal patients with systemic lupus erythematosus and low disease activity: a case–control study

Abstract Background The purpose of the present study was to compare dynamic muscle strength, functional performance, fatigue, and quality of life in premenopausal systemic lupus erythematosus (SLE) patients with low disease activity versus matched-healthy controls and to determine the association of dynamic muscle strength with fatigue, functional performance, and quality of life in SLE patients. Methods We evaluated premenopausal (18–45 years) SLE patients with low disease activity (Systemic lupus erythematosus disease activity index [SLEDAI]: mean 1.5 ± 1.2). The control (n = 25) and patient (n = 25) groups were matched by age, physical characteristics, and the level of physical activities in daily life (International Physical Activity Questionnaire IPAQ). Both groups had not participated in regular exercise programs for at least six months prior to the study. Dynamic muscle strength was assessed by one-repetition maximum (1-RM) tests. Functional performance was assessed by the Timed Up and Go (TUG), in 30-s test a chair stand and arm curl using a 2-kg dumbbell and balance test, handgrip strength and a sit-and-reach flexibility test. Quality of life (SF-36) and fatigue were also measured. Results The SLE patients showed significantly lower dynamic muscle strength in all exercises (leg press 25.63%, leg extension 11.19%, leg curl 15.71%, chest press 18.33%, lat pulldown 13.56%, 1-RM total load 18.12%, P < 0.001-0.02) compared to the controls. The SLE patients also had lower functional performance, greater fatigue and poorer quality of life. In addition, fatigue, SF-36 and functional performance accounted for 52% of the variance in dynamic muscle strength in the SLE patients. Conclusions Premenopausal SLE patients with low disease activity showed lower dynamic muscle strength, along with increased fatigue, reduced functional performance, and poorer quality of life when compared to matched controls.

Daily cycling of nitric oxide synthase (NOS) in the hippocampus of pigeons (C. livia)

Abstract: Background: Nitric oxide synthase (NOS) is essential for the synthesis of nitric oxide (NO), a non-conventional neurotransmitter with an important role in synaptic plasticity underlying processes of hippocampus-dependent memory and in the regulation of biological clocks and circadian rhythms. Many studies have shown that both the NOS cytosolic protein content and its enzymatic activity present a circadian variation in different regions of the rodent brain, including the hippocampus. The present study investigated the daily variation of NOS enzymatic activity and the cytosolic content of nNOS in the hippocampus of pigeons. Results: Adult pigeons kept under a skeleton photoperiod were assigned to six different groups. Homogenates of the hippocampus obtained at six different times-of-day were used for NOS analyses. Both iNOS activity and nNOS cytosolic protein concentrations were highest during the subjective light phase and lowest in the subjective dark phase of the circadian period. ANOVA showed significant time differences for iNOS enzymatic activity (p < 0.05) and for nNOS protein content (p < 0.05) in the hippocampus. A significant daily rhythm for both iNOS and nNOS was confirmed by analysis with the Cosinor method (p < 0.05). The present findings indicate that the enzymatic activity of iNOS and content of nNOS protein in the hippocampus of pigeons exhibit a daily rhythm, with acrophase values occurring during the behavioral activity phase. Conclusions: The data corroborate the reports on circadian variation of NOS in the mammalian hippocampus and can be considered indicative of a dynamic interaction between hippocampus-dependent processes and circadian clock mechanisms.