Patients with multiple sclerosis do not necessarily consume more alcohol or tobacco than the general population

Peer reviewedPublisher PD

Brazilian Registry of Cardiovascular Surgery in Adults. From design to reality

Universidade Federal de São Paulo (UNIFESP) Escola Paulista de MedicinaUniversidade Federal de São Paulo (UNIFESP) Faculdade de Medicina Instituto do CoraçãoUniversidade Federal do Rio Grande do NorteInstituto Nacional de CardiologiaUniversidade Estadual do Oeste do ParanáInstituto do CoraçãoUNIFESP, EPMUNIFESP, Faculdade de Medicina Instituto do CoraçãoSciEL

Results of nutritional intervention in children and adolescents with cystic fibrosis

Objective: few studies have verified longitudinally the evolution of the nutritional status of patients with cystic fibrosis. The objective of this study is to follow the evolution of the nutritional status, body composition and energy consumption, macronutrients and micronutrients ingested by children and adolescents by means of nutritional interventions at the Clinic of Cystic Fibrosis/Pediatric Pneumology of the Department of Pediatrics of Universidade Federal de São Paulo (UNIFESP). Methods: 18 patients were involved in this study, thirteen males and five females with ages ranging from 0.3 to 18.4 years. We performed three evaluations: evaluation 1 (M1- prenutritional intervention), M2 after 6 months, and M3 after 12 months. In these three instances we verified: the z score for weight/age, weight/height and height/age and the calculation of a 3-day diet record. We verified the body composition (anthropometry) in M1 and M3. The nutritional interventions were hypercaloric, hyperproteic, with adequate amount of ingested macronutrients and micronutrients.Results: we observed an increase in the z score for height/age (M1=-1.07; M2=-0.69; M3=-0.50) and fat-free mass after the nutritional interventions, without improvement in the z score for weight/height and fat mass. We verified an increase in the energy intake during M2 (139%) and M3 (132%) compared to M1 (106%). Remarkable increase in the intake of protein, calcium, iron and vitamin C by the patients was found. The occurrence of anemia was found in 44% (8/18) of the patients.Conclusion: the improvement of the z score in height/age and fat-free mass was probably due to the increase in energy consumption after the nutritional intervention. A significant improvement in the z score for weight/height and fat mass was not found, probably due to a gain in height and fat-free mass.Objetivo: poucos estudos têm verificado longitudinalmente a evolução do estado nutricional de pacientes com fibrose cística. O objetivo deste estudo foi acompanhar a evolução do estado nutricional, composição corporal e consumo de energia, macro e micronutrientes ingeridos por crianças e adolescentes, mediante intervenção nutricional, no Ambulatório de Fibrose Cística/Pneumologia Pediátrica, do Departamento de Pediatria da UNIFESP.Métodos: a casuística constituiu-se de 18 pacientes, sendo 13 do sexo masculino e 5 do feminino, faixa etária de 0,3 a 18,4 anos. Realizaram-se 3 avaliações: no momento 1 (M1: pré-intervenção nutricional), no M2, após 6 meses, e no M3, após 12 meses. Foram analisados nos 3 momentos: o escore Z de peso/idade (P/I), peso/estatura (P/E) e estatura/idade (E/I) e o cálculo do registro alimentar de 3 dias. No M1 e M3, verificou-se a composição corporal (antropometria). A conduta nutricional foi hipercalórica, hiperprotéica e houve adequação de macro e micronutrientes.Resultados: observou-se aumento significante do escore Z de E/I (M1=-1,07; M2=-0,69; M3=-0,50) e de massa magra após a intervenção nutricional, sem melhora no escore Z de P/E e massa gorda. Verificou-se aumento no consumo energético nos M2 (139%) e M3 (132%) em relação ao M1 (106%). Houve considerável aumento no consumo de proteína, cálcio, ferro e vitamina C pelos pacientes. A presença de anemia ocorreu em 44,4% (8/18) dos pacientes.Conclusão: o aumento no escore Z de E/I e massa magra ocorreu devido a adequação no consumo de energia, após a intervenção nutricional. Não houve melhora significante no escore Z de P/E e massa gorda, em função do ganho de estatura e de massa magra.UNIFESP-EPM Dep. de PediatriaHospital São Paulo Ambulatório de Fibrose CísticaUNISA Faculdade de MedicinaUNISA Dep. de PediatriaUNIFESP, EPM, Dep. de PediatriaHospital São Paulo Ambulatório de Fibrose CísticaSciEL

Performance assessment of polymer based electrodes for in vitro electrophysiological sensing: the role of the electrode impedance

Conducting polymer electrodes based on poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) are used to record extracellular signals from autonomous cardiac contractile cells and glioma cell cultures. The performance of these conducting polymer electrodes is compared with Au electrodes. A small-signal impedance analysis shows that in the presence of an electrolyte, both Au and polymer electrodes establish high capacitive double-layers. However, the polymer/electrolyte interfacial resistance is 3 orders of magnitude lower than the resistance of the metal/electrolyte interface. The polymer low interfacial resistance minimizes the intrinsic thermal noise and increases the system sensitivity. However, when measurements are carried out in current mode a low interfacial resistance partially acts as a short circuit of the interfacial capacitance, this affects the signal shape

Electrochemical noise and impedance of Au electrode/electrolyte interfaces enabling extracellular detection of glioma cell populations

Microelectrode arrays (MEA) record extracellular local field potentials of cells adhered to the electrodes. A disadvantage is the limited signal-to-noise ratio. The state-of-the-art background noise level is about 10 μVpp. Furthermore, in MEAs low frequency events are filtered out. Here, we quantitatively analyze Au electrode/electrolyte interfaces with impedance spectroscopy and noise measurements. The equivalent circuit is the charge transfer resistance in parallel with a constant phase element that describes the double layer capacitance, in series with a spreading resistance. This equivalent circuit leads to a Maxwell-Wagner relaxation frequency, the value of which is determined as a function of electrode area and molarity of an aqueous KCl electrolyte solution. The electrochemical voltage and current noise is measured as a function of electrode area and frequency and follow unambiguously from the measured impedance. By using large area electrodes the noise floor can be as low as 0.3 μVpp. The resulting high sensitivity is demonstrated by the extracellular detection of C6 glioma cell populations. Their minute electrical activity can be clearly detected at a frequency below about 10 Hz, which shows that the methodology can be used to monitor slow cooperative biological signals in cell populations.</p

Acidocalcisomes as Calcium- and Polyphosphate-Storage Compartments during Embryogenesis of the Insect Rhodnius prolixus Stahl

BACKGROUND: The yolk of insect eggs is a cellular domain specialized in the storage of reserve components for embryo development. The reserve macromolecules are stored in different organelles and their interactions with the embryo cells are mostly unknown. Acidocalcisomes are lysosome-related organelles characterized by their acidic nature, high electron density and large content of polyphosphate bound to several cations. In this work, we report the presence of acidocalcisome-like organelles in eggs of the insect vector Rhodnius prolixus. METHODOLOGY/PRINCIPAL FINDINGS: Characterization of the elemental composition of electron-dense vesicles by electron probe X-ray microanalysis revealed a composition similar to that previously described for acidocalcisomes. Following subcellular fractionation experiments, fractions enriched in acidocalcisomes were obtained and characterized. Immunofluorescence showed that polyphosphate polymers and the vacuolar proton translocating pyrophosphatase (V-H(+)-PPase, considered as a marker for acidocalcisomes) are found in the same vesicles and that these organelles are mainly localized in the egg cortex. Polyphosphate quantification showed that acidocalcisomes contain a significant amount of polyphosphate detected at day-0 eggs. Elemental analyses of the egg fractions showed that 24.5±0.65% of the egg calcium are also stored in such organelles. During embryogenesis, incubation of acidocalcisomes with acridine orange showed that these organelles are acidified at day-3 (coinciding with the period of yolk mobilization) and polyphosphate quantification showed that the levels of polyphosphate tend to decrease during early embryogenesis, being approximately 30% lower at day-3 compared to day-0 eggs. CONCLUSIONS: We found that acidocalcisomes are present in the eggs and are the main storage compartments of polyphosphate and calcium in the egg yolk. As such components have been shown to be involved in a series of dynamic events that may control embryo growth, results reveal the potential involvement of a novel organelle in the storage and mobilization of inorganic elements to the embryo cells

An electrical method to measure low-frequency collective and synchronized cell activity using extracellular electrodes

An electrical method to measure extracellular bioelectrical activity in vitro is presented. This method exploits the Helmholtz capacitive double-layer established at the electrode surface. Small extracellular voltage variations in the order of μVs induce through the double-layer capacitor a displacement current that is measured. This current is then enhanced by a gain factor proportional to the electrode capacitance. In addition, when measurements are carried out at low frequencies in current mode the electrode contribution to the noise can be minimized. The performance of the electrodes and the method is demonstrated using zebrafish hearts and glioma cell cultures. We propose that this electrical method is an ideal tool to measure in vitro slow and temporally synchronized events that are often involved in long range intracellular signaling.</p

Salt stress tolerance in cowpea is poorly related to the ability to cope with oxidative stress

We have previously demonstrated that salt tolerance in cowpea could be associated with lesser impairments of the photosynthetic capacity. Taking into account that photosynthesis is the main sink for reducing power consumption, our central working hypothesis is that a salt- sensitive cultivar is more prone to suffer from oxidative stress. We analyzed the long-term effects of salt stress on oxidative damage and protection against reactive oxygen species in both leaves and roots of a salt-tolerant (Pitiúba) and a salt-sensitive (TVu) cowpea cultivar. Two salt treatments (0 and 75 mM NaCl) were applied to 10-day-old plants grown in nutrient solution for 24 days. Significant salt-induced oxidative damage as demonstrated via increases in malondialdehyde concentration were noted, particularly in leaves at the end of the experiment, although such damage was found earlier in Pitiúba. In salt-stressed plants, superoxide dismutase (SOD) activity increased only in Pitiúba at 24 days from the start of salt additions (DSSA). In Pitiúba, catalase (CAT) was not significantly affected by the treatments, whereas in TVu its activity was dramatically lower in salt- tressed plants at 10DSSAonwards. In general salt stress led to significant increases, much more pronounced in ascorbate peroxidase (APX), glutathione reductase (GR) and guaiacol peroxidase (GPX), at the end of the experiment in both cultivars. In roots, salt-induced increases in enzyme activities were particularly noted at 24 DSSA, as found for SOD and APX in Pitiúba, CAT in TVu and GR and GPX in both cultivars. Therefore, in contrast to our expectations, the present results argue, to a great extent, against a functional link between salt stress tolerance and the expression of the antioxidant system. We also demonstrated that leaves and roots should be evaluated for a full assessment of whole plant acclimation to salt stress