Associations of occupational physical activity and active transport with depressive symptoms in a middle-income country.

OBJECTIVE: This study investigated the associations of occupational physical activity and active transport with depressive symptoms, stratified by income range, among Brazilian working adults. STUDY DESIGN: This cross-sectional study drew on data from the 2019 Brazilian National Health Survey. METHODS: We used the Patient Health Questionnaire (PHQ-9) to assess depressive symptoms in working adults aged 18-65 years, with physical activities (occupational physical activity and active transport) self-reported through a specially developed questionnaire. Crude and adjusted logistic regression models were fitted. RESULTS: Individuals at the highest level of occupational physical activity (odds ratio [OR] 1.35; 95% confidence interval [95% CI] 1.19-1.53) and at the moderate level of active transport to work (OR 1.66; 95% CI 1.24-2.22) returned increased odds of depressive symptoms as compared with those who were inactive in these domains. Stratified by income group, light active transport to work (OR 0.57; 95% CI 0.34-0.95) in the lower income group (Range 1) was associated with lower odds of depressive symptoms. On the other hand, individuals at the highest level of active transport to work returned higher odds of depressive symptoms in the low- and intermediate-income groups, Ranges 3 and 4 (OR 1.92; 95% CI 1.22-3.00 and OR 2.91; 95% CI 1.71-4.95, respectively). CONCLUSION: Our results suggest that occupational physical activity and active transport may be a risk factor for depressive symptoms. They also point to differences in this relationship by income range. Further studies are needed to pursue the analysis of how specific domains of physical activity contribute to depressive symptoms.

Frequency of leisure-time physical activity and pulse pressure in the Brazilian population: a population-based study.

OBJECTIVE: The purpose of this study was to investigate the association between the frequency of leisure-time physical activity and brachial pulse pressure (PP), according to physical activity intensity and type, sex, and age, in the general Brazilian population. STUDY DESIGN: This was a cross-sectional study based on data from the Brazilian 2013 National Health Survey. METHODS: The sample consisted of 20,058 men and 20,600 women aged between 18 and 65 years. The frequency of leisure-time physical activity was obtained through a questionnaire and classified according to intensity (vigorous or moderate) and type (cyclic or acyclic). We calculated PP as the difference between systolic and diastolic blood pressures based on the measure of a digital pressure device. Multiple linear regression analysis was applied to analyze the association of different sexes, frequency, type, and intensity of leisure-time physical activity and PP. RESULTS: Adjusted results showed that one session of moderate physical activity per week could benefit men's PP: ß = -1.87 mmHg; SE = 0.83. For women, the adjusted model reveals that physical activity undertaken twice a week is sufficient to benefit PP: ß = -1.77 mmHg; SE = 0.72. However, according to type, two times a week of acyclic activities increased PP in men: ß = 2.62 mmHg; SE = 0.62 and decreased in women: ß = -2.67 mmHg; SE = 0.72. CONCLUSIONS: Our results suggest that low frequencies of leisure-time physical activity are sufficient to induce beneficial effects on the cardiovascular system for both sexes. Also, there are some differences between sexes in cardiac adaptations according to type, frequency, and intensity of physical activity.

Cell wall polysaccharides from in vitro propagated Cereus hildmannianus K. Schum. plants.

Cereus hildmannianus is a cactus exhibiting morphological and physiological adaptation of its cladodes which ensuring growth in climatic and soil conditions unfavourable for many plant species. Currently, limited water resources and increasing demand for renewable energy make cacti a biomass source for the production of biofuels. Somaclones regenerated from callus in vitro can be a source of new raw material in useful plants. The objective of this work was to determine if the regenerated plants showing two different morphologies present polysaccharide composition different from the wild plant. Somaclones aqueous extraction shows the absence of soluble polysaccharides as mucilage. The alkaline extraction of in vivo cultivated plant showed the presence of starch, type I arabinogalactan, and arabinoxylan and the somaclones showed type I arabinogalactan and arabinoxylan in both morphologies. Hemicelluloses found in the somaclones are not different from in vivo cultivated plants, but somaclones not almost biosynthesize mucilage and starch.

Nerve transfers for acute flaccid myelitis: a case series.

BACKGROUND: Acute flaccid myelitis (AFM) syndrome consists of loss of lower motor neurons following a viral infection, with preserved sensory function. It usually affects the upper limbs asymmetrically, with proximal more than distal muscle involvement. METHODS: Five cases were surgically treated with nerve transfers: spinal accessory to suprascapular nerve transfer (4 patients), branch of radial nerve to axillary nerve transfer (Somsak's procedure) (2 patients), and transfer of a fascicle of the ulnar nerve to the motor branch to the biceps (Oberlin's procedure) (1 patient). RESULTS: Motor improvement was seen in three cases. Widespread motor involvement was associated with poor outcome. CONCLUSION: This small series of cases reinforces that nerve transfers are a reliable option for treatment of selected children with AFM.

Oxygen diffusion and vacancy migration thermally-activated govern high-temperature magnetism in ceria.

Several experimental works currently demonstrate that metallic nano-oxides and carbon nanomaterials expected to be diamagnets, in fact, behave as ferromagnets at room temperature. More than scientifically intriguing, this unconventional and unexpected ferromagnetism pave the way for innovation products and novel nanotechnological applications, gathering the magnetism to interesting functionalities of these nanomaterials. Here, we investigate the non-conventional ferromagnetism observed at high temperatures in nanocrystalline cerium dioxide (CeO2or nanoceria) thin films that are optically transparent to visible light. Nanoceria exhibits several concrete applications in catalytic processes, photovoltaic cells, solid-state fuel cells, among others, which are mostly due to natural presence of oxygen vacancies and easy migration of the oxygen through the structure. The ferromagnetism in non-stoichiometric nanocrystaline ceria can be consistently described by ab initio electronic structure calculations, which support that oxygen vacancies cause the formation of magnetic moments and can provide a robust interconnectivity within magnetic polarons theoretical framework. Additionally, we present a conceptual model to account the oxygen transport to the non-conventional ferromagnetism at temperatures well above room temperature. The approach is complementary to the thermally-activated effective transfers of charge and spin around oxygen vacancy centers.

Grain structure and magnetic relaxation of self-assembled Co nanowires.

The magnetic relaxation of Co nanowires assemblies embedded in CeO(2)/SrTiO(3)(001) epilayers has been investigated by magnetization decay measurements. Two different samples were studied, with nanowires having distinct crystallographic structures and diameters of 3 and 5 nm. The structure of the nanowires was derived from high-resolution transmission electron microscopy analysis. The 3 nm diameter nanowires are made of hcp Co grains with the c-axis pointing along one of the four <111> directions of the CeO(2) matrix, separated by fcc Co regions. In the 5 nm diameter nanowires, the grains are smaller and the density of stacking faults is much higher. The magnetic viscosity coefficient (S) of these two systems was measured as a function of the applied field and of the temperature. Analysis of the variation of S and of the activation volume for magnetization reversal reveals distinct behaviors for the two systems. In the nanowires assembly with 5 nm diameter, the results can be described by considering an energy barrier distribution related to shape anisotropy and are consistent with a thermally activated reversal of the magnetization. In contrast, the anomalous behavior of the 3 nm diameter wires indicates that additional sources of anisotropy have to be considered in order to describe the distribution of energy barriers and the reversal process. The distinct magnetic behaviors observed in these two systems can be rationalized by considering the grain structure of the nanowires and the resulting effective magnetocrystalline anisotropy.

Mechanism of localization of the magnetization reversal in 3 nm wide Co nanowires.

The mechanism of magnetization reversal has been studied in a model system of self-assembled cobalt nanowires with a 3 nm diameter. The structure, orientation and size of grains within the nanowires could be determined by high resolution transmission electron microscopy. The magnetic properties were probed using static and dynamic magnetization measurements. Micromagnetic modeling based on the structural analysis allows us to correlate the structure and the magnetic behavior of the wires, revealing competition between shape anisotropy, magnetocrystalline anisotropy and exchange in the localized reversal within Co hcp oriented grains. These results provide direct experimental evidence of the link between anisotropy fluctuations and reversal localization in nanowires.

Ferromagnetism induced by oxygen and cerium vacancies above the percolation limit in CeO2.

We studied the structural, chemical and magnetic properties of non-doped ceria (CeO(2)) thin films electrodeposited on silicon substrates. Experimental results confirm that the observed room temperature ferromagnetism is driven by both cerium and oxygen vacancies. We investigated ceria films presenting vacancy concentrations well above the percolation limit. Irradiation experiments with neon ions were employed to generate highly oxygen defective CeO(2-δ) structures. X-ray photoelectron spectroscopy and x-ray absorption near-edge structure spectroscopy were used to estimate the concentration of Ce(3+) sites in the films, which can reach up to 50% of Ce(3+) replacing Ce(4+), compared to a stoichiometric CeO(2) structure. Despite the increment of structural disorder, we observe that the saturation magnetization continuously increases with Ce(3+) concentration. Our experiments demonstrate that the ferromagnetism observed in ceria thin films, highly disordered and oxygen-deficient, preserving the fluorite-type structure only in a nanometer scale, remains intrinsically stable at room temperature.

Electrochemical preparation of overlapped porous layers on anodic alumina.

In this paper, we report the development of a new architecture on porous anodic alumina using the conventional two-step anodization method. The samples prepared in two identical steps using galvanostatic anodization exhibited two porous layers overlapped with distinct pore area distributions. The effects from the first anodization time and temperature on this different morphology were assessed using Factorial Design. The chemical removal time of the oxide formed during the first anodization was not relevant for the overlapped porous structure. The most important factor was the time of the first anodization required for formation of stable patterns on the substrate, which would be reproduced in the second anodization. A pore mismatch appeared because under galvanostatic control the changes in the actual area become important, which is not the case for sample preparation under potentiostatic control where the current density is adjusted according to the new boundary condition. The new architecture with mismatching layers may open the way for further applications of porous alumina as template for nanomaterial.

Can the fractal dimension be applied for the early diagnosis of non-proliferative diabetic retinopathy?

The fractal dimension has been employed as a useful parameter in the diagnosis of retinal disease. Avakian et al. (Curr Eye Res 2002; 24: 274-280), comparing the vascular pattern of normal patients with mild to moderate non-proliferative diabetic retinopathy (NPDR), found a significant difference between them only in the macular region. This significant difference in the box-counting fractal dimension of the macular region between normal and mild NPDR patients has been proposed as a method of precocious diagnosis of NPDR. The aim of the present study was to determine if fractal dimensions can really be used as a parameter for the early diagnosis of NPDR. Box-counting and information fractal dimensions were used to parameterize the vascular pattern of the human retina. The two methods were applied to the whole retina and to nine anatomical regions of the retina in 5 individuals with mild NPDR and in 28 diabetic but opthalmically normal individuals (controls), with age between 31 and 86 years. All images of retina were obtained from the Digital Retinal Images for Vessel Extraction (DRIVE) database. The results showed that the fractal dimension parameter was not sensitive enough to be of use for an early diagnosis of NPDR.

Can the fractal dimension be applied for the early diagnosis of non-proliferative diabetic retinopathy?

The fractal dimension has been employed as a useful parameter in the diagnosis of retinal disease. Avakian et al. (Curr Eye Res 2002; 24: 274-280), comparing the vascular pattern of normal patients with mild to moderate non-proliferative diabetic retinopathy (NPDR), found a significant difference between them only in the macular region. This significant difference in the box-counting fractal dimension of the macular region between normal and mild NPDR patients has been proposed as a method of precocious diagnosis of NPDR. The aim of the present study was to determine if fractal dimensions can really be used as a parameter for the early diagnosis of NPDR. Box-counting and information fractal dimensions were used to parameterize the vascular pattern of the human retina. The two methods were applied to the whole retina and to nine anatomical regions of the retina in 5 individuals with mild NPDR and in 28 diabetic but opthalmically normal individuals (controls), with age between 31 and 86 years. All images of retina were obtained from the Digital Retinal Images for Vessel Extraction (DRIVE) database. The results showed that the fractal dimension parameter was not sensitive enough to be of use for an early diagnosis of NPDR.

Basal metabolic rate and body composition in patients with post-polio syndrome.

The aim of this study was to compare basal metabolic rate (BMR) of post-polio syndrome (PPS) patients with healthy individuals and to determine its correlation to body composition. BMR (kcal/day) was determined by indirect calorimetry and body composition by dual energy X-ray absorptiometry. BMR was lower in the PPS patient group than in the control group, although it was similar in both groups when adjusted for body surface area, total body mass (TBM), lean body mass (LBM) and fat-free mass (FFM). PPS patients also showed reduced TBM, LBM and FFM in relation to controls. As muscle energy expenditure while at rest contributes only 20% to the BMR, a proportional reduction in BMR and FFM or LBM could suggest that muscle mass or other factors may interfere more than predicted. It was concluded that the prediction of BMR from the Harris-Benedict equation in PPS patients must be carefully reviewed.

Magnetic properties of synthetic eumelanin--preliminary results.

We report an experimental and theoretical study of magnetic properties of synthetic eumelanin. The magnetization curves are determined by using both a vibrating sample magnetometer and a superconducting quantum interferometer device in an extended range of magnetic fields ranging from -10 kOe to 10 kOe at different temperatures. We find that the eumelanin magnetization can be qualitatively explained in terms of a simple model of dipolar spheres with an intrinsic magnetic moment. The latter one is experimentally measured by using X-band electron paramagnetic resonance. Our findings indicate that synthetic melanins are superparamagnetic.

Antileishmanial activity of indole alkaloids from Aspidosperma ramiflorum.

The present study was designated to evaluate the antileishmanial activity of acid and basic fractions that were obtained after acid-basic extraction, from ethanolic 70% crude extract and pure compounds from the stem bark of Aspidosperma ramiflorum. The basic alkaloidal fraction presented a good activity against the extracellular form (promastigotes) of Leishmania (L.) amazonensis (LD(50) value<47 microg/ml). Based on these findings, the basic fraction was fractionated on silica gel column chromatography in a bioassay-guided fractionation affording individual purified ramiflorines A and B. Both ramiflorines A and B showed significant activity against Leishmania (L.) amazonensis (LD(50) values of 16.3+/-1.6 microg/ml and 4.9+/-0.9 microg/ml, respectively). Our results are promising, showing that these compounds are biologically active against Gram-positive bacteria.

Antibacterial activity of indole alkaloids from Aspidosperma ramiflorum

We evaluated the antibacterial activities of the crude methanol extract, fractions (I-V) obtained after acid-base extraction and pure compounds from the stem bark of Aspidosperma ramiflorum. The minimum inhibitory concentration (MIC) was determined by the microdilution technique in Mueller-Hinton broth. Inoculates were prepared in this medium from 24-h broth cultures of bacteria (10(7) CFU/mL). Microtiter plates were incubated at 37°C and the MICs were recorded after 24 h of incubation. Two susceptibility endpoints were recorded for each isolate. The crude methanol extract presented moderate activity against the Gram-positive bacteria B. subtilis (MIC = 250 µg/mL) and S. aureus (MIC = 500 µg/mL), and was inactive against the Gram-negative bacteria E. coli and P. aeruginosa (MIC > 1000 µg/mL). Fractions I and II were inactive against standard strains at concentrations of <=1000 µg/mL and fraction III displayed moderate antibacterial activity against B. subtilis (MIC = 500 µg/mL) and S. aureus (MIC = 250 µg/mL). Fraction IV showed high activity against B. subtilis and S. aureus (MIC = 15.6 µg/mL) and moderate activity against E. coli and P. aeruginosa (MIC = 250 µg/mL). Fraction V presented high activity against B. subtilis (MIC = 15.6 µg/mL) and S. aureus (MIC = 31.3 µg/mL) and was inactive against Gram-negative bacteria (MIC > 1000 µg/mL). Fractions III, IV and V were then submitted to bioassay-guided fractionation by silica gel column chromatography, yielding individual purified ramiflorines A and B. Both ramiflorines showed significant activity against S. aureus (MIC = 25 µg/mL) and E. faecalis (MIC = 50 µg/mL), with EC50 of 8 and 2.5 µg/mL for ramiflorines A and B, respectively, against S. aureus. These results are promising, showing that these compounds are biologically active against Gram-positive bacteria.

Antibacterial activity of indole alkaloids from Aspidosperma ramiflorum.

We evaluated the antibacterial activities of the crude methanol extract, fractions (I-V) obtained after acid-base extraction and pure compounds from the stem bark of Aspidosperma ramiflorum. The minimum inhibitory concentration (MIC) was determined by the microdilution technique in Mueller-Hinton broth. Inoculates were prepared in this medium from 24-h broth cultures of bacteria (10(7) CFU/mL). Microtiter plates were incubated at 37 masculineC and the MICs were recorded after 24 h of incubation. Two susceptibility endpoints were recorded for each isolate. The crude methanol extract presented moderate activity against the Gram-positive bacteria B. subtilis (MIC = 250 microg/mL) and S. aureus (MIC = 500 microg/mL), and was inactive against the Gram-negative bacteria E. coli and P. aeruginosa (MIC > 1000 microg/mL). Fractions I and II were inactive against standard strains at concentrations of < or =1000 microg/mL and fraction III displayed moderate antibacterial activity against B. subtilis (MIC = 500 microg/mL) and S. aureus (MIC = 250 microg/mL). Fraction IV showed high activity against B. subtilis and S. aureus (MIC = 15.6 microg/mL) and moderate activity against E. coli and P. aeruginosa (MIC = 250 microg/mL). Fraction V presented high activity against B. subtilis (MIC = 15.6 microg/mL) and S. aureus (MIC = 31.3 microg/mL) and was inactive against Gram-negative bacteria (MIC > 1000 microg/mL). Fractions III, IV and V were then submitted to bioassay-guided fractionation by silica gel column chromatography, yielding individual purified ramiflorines A and B. Both ramiflorines showed significant activity against S. aureus (MIC = 25 microg/mL) and E. faecalis (MIC = 50 microg/mL), with EC50 of 8 and 2.5 microg/mL for ramiflorines A and B, respectively, against S. aureus. These results are promising, showing that these compounds are biologically active against Gram-positive bacteria.

P-glycoprotein-like protein contributes to cadmium resistance in Euglena gracilis.

Selective pressures from polluted environments have led to the development of resistance systems in aquatic organisms. Using different techniques, this study examined a cadmium defense mechanism of the freshwater unicellular protozoa Euglena gracilis, and found it to be an efflux pump similar to the multidrug resistance P-glycoprotein. Cd(2+)-treated E. gracilis were able to extrude Rhodamine 123 at 21 degrees C, but not at 4 degrees C. Furthermore, verapamil, a P-glycoprotein modulator, partially blocked the efflux process (at 21 degrees C), and enhanced the Cd(2+) toxic effects on these cells. Western immunoblots of cell lysates, using the anti-P-glycoprotein antibody JSB-1, revealed a 120-KDa protein, which was expressed, in high amounts on Cd(2+)-exposed cells (74% above the control values). Moreover, cells treated with JSB-1 became more sensitive to the harmful effects of cadmium, showing a decreased survival rate. Taken together, these results suggest that a MDR phenotype has evolved in Euglena as one of the mechanisms for cadmium detoxification.