El consumo de la polidextrosa previene la obesidad y sus comorbilidades en ratas alimentados con dieta hipercalórica / Polydextrose consumption prevents obesity and comorbidities in rats fed with a hypercaloric diet

RESUMEN El objetivo de este trabajo fue evaluar el efecto de las diferentes concentraciones de polidextrosa en la prevención de la obesidad y sus comorbilidades, en ratas alimentados con dieta hipercalórica. Se utilizaron ratas machos Wistar, repartidos en 4 grupos: Grupo control (HC) y 3 grupos que recibieron dieta hipercalórica con suplementación del 2%, 4% y 6% de polidextrosa (HC2%P, HC4%P y HC6%P respectivamente). La dieta hipercalórica utilizada fue la del tipo de cafetería para inducir la obesidad. Se midió peso corporal e ingesta de la dieta, se realizaron pruebas de tolerancia a la glucosa y a la insulina. Los animales fueron sometidos a eutanasia para toma de muestra de sangre medidas antropométricas y pesaje de órganos y tejidos. La polidextrosa disminuyó significantemente el peso, la grasa corporal, la glicemia, los triglicéridos, la intolerancia a la glucosa y la resistencia a la insulina, y aumentó los niveles del colesterol HDL. Se concluye que el consumo de poli- dextrosa redujo las complicaciones derivadas de la obesidad en ratas alimentados con dieta hipercalórica, siendo éste un potencial tratamiento para el control de la obesidad, la diabetes tipo II y las enfermedades cardiovasculares.

ABSTRACT The aim of this study was to evaluate the effect of different polydextrose concentrations for the prevention of obesity and its comorbidities in rats fed a high calorie diet. Thirty male Wistar rats were used. Rats were divided into 4 groups: Control group (HC) and 3 groups which received a hypercaloric diet with 2%, 4% and 6% polydextrose supplementation (HC2%P, HC4%P and HC6%P, respectively). The hypercaloric diet used was of the cafeteria type to induce obesity. Body weight and feed intake were verified weekly. Glucose and insulin tolerance tests were performed five days before finalizing the experiment. At the end of the experiment, animals were euthanized for blood collection, anthropometric measurements and tissue weighing. Polydextrose significantly decreased weight, body fat, blood glucose, triglycerides, glucose intolerance and insulin resistance and increased HDL cholesterol levels. The use of polydextrose reduced the complications of obesity in mice fed a hypercaloric diet. In conclusion, polydextrose may be a promising treatment for controlling obesity, diabetes type II and cardiovascular diseases.

Massaranduba Sawdust: A Potential Source of Charcoal and Activated Carbon.

This paper provides proof of concept that activated carbon (AC) may be readily produced using limited conversion methods and resources from sawdust of massaranduba (Manilkara huberi) wood, thereby obtaining value-added products. Sawdust was sieved and heat-treated in an oxygen-free muffle furnace at 500 °C to produce charcoal. The charcoal was activated in a tubular electric furnace at 850 °C while being purged with CO2 gas. Microstructural, thermal and physical properties of the three components: sawdust, charcoal and AC were compared by means of field emission scanning electron microscopy (FESEM), X-ray diffractometry (XRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), density and water adsorption/desorption measurements. The resulting AC had a large surface area as measured by Brunauer-Emmett-Teller (BET) comparable to other such values found in the literature. The large surface area was due to pore development at the microstructural level as shown by FESEM. XRD illustrated that sawdust had a semi-crystalline structure whereas charcoal and AC evidenced mostly amorphous structures. TGA and DSC showed that AC had high reactivity to moisture compared to sawdust and charcoal.

Microwave-assisted digestion of organic samples: how simple can it become?

Advancements in sample preparation for performing trace analysis of inorganic analytes are coming from the dissemination of microwave-assisted procedures, but there is still room for improvements by looking for simple and easily applied procedures. Recently it was proposed a new approach called single reaction chamber with capability for digestions at high pressures and temperatures using simple vials and racks. This was a limitation of former cavity microwave ovens with closed vessels. It was demonstrated here that the use of single reaction chamber approach allows the implementation of efficient digestions using diluted solutions of nitric acid and also allows addressing a critical need of sample preparation for inorganic analysis by running mixed batches of samples. The feasibility of this procedure was demonstrated for organic samples and accuracy was proved by using certified reference materials of apple leaves, bovine liver and whole milk powder. Digestions performed of whole milk powder and bovine liver using 2.0 mol L(-1) nitric acid solution plus concentrated hydrogen peroxide at 240 °C led to residual carbon contents of 0.825 and 1.50% and residual acidities of 1.04 and 0.618 mol L(-1), respectively. These parameters are fully compatible with further measurements using ICP OES or ICP-MS. Al, Cu, Fe, Mn, Mo, Rb, Se, Sr, and Zn were accurately determined by ICP OES or ICP-MS depending on their concentrations in digests.

Duplications involving a conserved regulatory element downstream of BMP2 are associated with brachydactyly type A2.

Autosomal-dominant brachydactyly type A2 (BDA2), a limb malformation characterized by hypoplastic middle phalanges of the second and fifth fingers, has been shown to be due to mutations in the Bone morphogenetic protein receptor 1B (BMPR1B) or in its ligand Growth and differentiation factor 5 (GDF5). A linkage analysis performed in a mutation-negative family identified a novel locus for BDA2 on chromosome 20p12.3 that incorporates the gene for Bone morphogenetic protein 2 (BMP2). No point mutation was identified in BMP2, so a high-density array CGH analysis covering the critical interval of approximately 1.3 Mb was performed. A microduplication of approximately 5.5 kb in a noncoding sequence approximately 110 kb downstream of BMP2 was detected. Screening of other patients by qPCR revealed a similar duplication in a second family. The duplicated region contains evolutionary highly conserved sequences suggestive of a long-range regulator. By using a transgenic mouse model we can show that this sequence is able to drive expression of a X-Gal reporter construct in the limbs. The almost complete overlap with endogenous Bmp2 expression indicates that a limb-specific enhancer of Bmp2 is located within the identified duplication. Our results reveal an additional functional mechanism for the pathogenesis of BDA2, which is duplication of a regulatory element that affects the expression of BMP2 in the developing limb.

Age-related white matter lesions are associated with reduction of the apparent diffusion coefficient in the cerebellum.

Cerebellar apparent diffusion coefficient (ADC) was found to be increased after acute cerebral hemispheric stroke. There are no data on cerebellar ADC changes in patients with chronic, age-related white matter lesions (ARWML). We aimed to determine longitudinal ADC variations on cerebral hemispheric and cerebellar white matter regions of patients with ARWML in order to study relations between ADC changes in both regions. ADC was measured serially (1-year interval) on lesioned periventricular frontal white matter, frontal and parietoccipital normal appearing white matter and middle cerebellar peduncles, on 19 aged patients with ARWML, which also underwent gait assessment. We compared regional ADC at 0 and 1 year and calculated variation percentages for each region. Correlation analysis was made between ADC variation in cerebellar regions and in contralateral hemispheric regions and between cerebellar ADC at 1 year and walking speed. After 1 year, ADC was higher on lesioned periventricular frontal white matter and lower on cerebellar regions. ADC variations on these regions were negatively correlated. Cerebellar ADC measured after 1 year was positively correlated with walking speed. This suggests a link between vascular disease progression inside frontal lesions and ADC reduction in contralateral cerebellar peduncles. Chronic ischemia in frontal white matter could have interrupted frontal-cerebellar circuits, producing hypometabolism in cerebellar regions (and worse performance on motor tasks), decreased perfusion and hence ADC reduction.

Reduction of heavy metal contents in liquid effluents by vermicomposts and the use of the metal-enriched vermicomposts in lettuce cultivation.

The removal of Cu, Ni and Zn from electroplating effluents by adsorption in cattle manure vermicompost has been discussed. A glass column 38 cm long and 7 cm i.d. was loaded with cattle manure vermicompost and effluents were passed through it. The metal concentrations were measured in the elutant. The experiments on adding effluent aliquots into the columns were continued until the metal concentrations in the elutant reached the maximum values established for effluent discharges in water courses by the Brazilian quality criteria, i.e., Cu=1.0 mg L(-1), Ni=2.0 mg L(-1), and Zn=5.0 mg L(-1). The amount of Cu retention by the vermicompost was determined at the natural effluent pH (2.0). The Zn and Ni retentions were evaluated at the natural effluent pH (6.9 and 7.4, respectively) as well pH 2.0. Vermicompost residues obtained from this process were used for lettuce cultivation. The vermicompost was found to be efficient in removing metals from the electroplating wastes, as well as in the increase of its pH values. Metal retention values were close to 100%. The Cu concentrations in lettuce leaves from the treatment with vermicompost enriched with this metal were below the range of critical toxicity level to plants, i.e., from 20 to 100 mg L(-1). However, the estimated Cu concentrations in the roots from the treatment with vermicompost enriched with Cu were much larger than that of the treatment with the natural vermicompost, reaching 246.3 mg L(-1). The Ni and Zn concentrations in lettuce leaves from the treatments, with vermicomposts enriched with the respective metals, were above the range of critical toxicity levels to plants, i.e., from 10 to 50 mg kg(-1) and from 15 to 30 mg kg(-1), respectively. However, no symptom of toxicity was found visually. Larger accumulations of Cu, Ni and Zn were found in the lettuce leaves than in the roots after the treatments with the uncontaminated vermicompost. A greater absorption of Cu and Ni by roots was found in treatments with vermicompost enriched with these elements, whereas Zn was found preferentially in the leaves. The statistical analysis was done by analyses of variance and regression.

Environmental assessment of water-courses of the Turvo Limpo River basin at the Minas Gerais State, Brazil.

A study was performed to evaluate the environmental contamination in the Turvo Limpo River basin which receives effluent discharges from domestic (residential and commercial) activities. The watercourses examined were the São Bartolomeu Stream, Turvo Sujo River, and Turvo Limpo River, located in the Minas Gerais State, Brazil. Water samples were collected at the river-side and analyzed for evaluation of pollutant inputs. The pH, temperature, electrical conductivity, redox potential (Eh), dissolved oxygen (DO), total and settleable solids, visual color, hardness, chemical oxygen demand (COD), biochemical oxygen demand (BOD), chloride, total phosphate, total nitrogen, ammonia nitrogen, nitrate, total coliforms and E. coli, as well as the Cd, Pb, Cu, and Zn speciation were determined in the watercourses. The data obtained were compared with those of the Brazilian Environmental Standards and with data from non-contaminated areas. River water characteristics in some sites were far from the limit values established for superficial waters with satisfactory quality. For instance, the BOD values reached 411 mg L(-1) for a maximum limit of 10.0 mg L(-1), while the ammonia nitrogen concentration reached 28 mg L(-1) for a maximum limit of 13.3 mg L(-1). Some sites showed E. coli values above those of non-contaminated regions. Besides the effects of sewage discharges into the water-courses, agriculture activities and the use of the area for cattle husbandry influenced the quality of the river waters, for instance, the pH of a spring-water sample reached the value of 4.3. The São Bartolomeu Stream has been contributing to the deterioration of the water quality of the Turvo Sujo River, while the Turvo Limpo River has also been affected by anthropogenic discharges in the Turvo Sujo River. The speciation of Cd, Cu and Pb showed that these metals were mainly found in the particulate fraction (i. e., associated with the suspended material). Fifty five percent of the water samples showed labile Zn concentrations greater than that of the nonlabile Zn.

Heavy metal availability in soil amended with composted urban solid wastes.

A study was performed to evaluate the pH and the availability of Zn, Cu, Mn, Pb, and Ni in soil amended with increasing doses of composted solid wastes, collected in Rio de Janeiro, Rio de Janeiro State and in Coimbra, Minas Gerais State, Brazil. The influence of the time elapsed between compost application to the soil and the sampling of the plant growth substrate (soil + compost) for pH and metal availability analyses was also examined. The availability of heavy metals in the soil, in the compost and in the substrate was evaluated using DTPA solution for metal extraction. The increase of the compost doses added to the soil resulted in the increase of the pH in the substrate. The addition of the compost from the bigger city, Rio de Janeiro, resulted in higher increase in soil pH and available Zn, Cu, Pb, and Ni levels as compared to the addition of the compost from the smaller city, Coimbra. Increasing the time elapsed between the compost application to the soil and the sampling of the mixture resulted in higher available Zn, Cu, Mn, and Pb levels. The addition of the compost from Rio de Janeiro resulted in substrate metal concentrations in the order Zn > Pb > Ni > Cu > Mn and for the Coimbra compost the metal concentrations in the substrate was Zn > Pb > Cu > Ni > Mn. The higher values of pH and available metals obtained for the bigger city were attributed to the greatest metal contamination of its compost.

Assessment of water systems for contaminants from domestic and industrial sewages.

The State of Minas Gerais represents one of Brazil's most outstanding mining resources. The contamination of river water from kaolin processing activities may be harmful to people in the way of slow but chronic poisoning. On the other hand, the discharge of untreated or inadequately treated domestic sewage into aquatic environments can also cause deleterious effects to the health. However, no reliable figures are available for pollutant occurrences in river water. This draws attention to the very precarious situation that exists with respect to pollution by organic and inorganic toxic wastes, especially with respect to humans and fauna in all its expressions. Thus, with the purpose of establishing a preliminary report to trace out industrialisation outcomes, samples of river water, vegetation and fish were collected and analysed to detect pollutant inputs. The concentration of metals was determined in suspended particle, vegetation and fish, while those of nitrite, nitrate, phosphate and chloride were determined in river water samples. The concentration of dissolved oxygen (DO) was measured in river water at the time of collection. Chemical oxygen demand (COD) and biochemical oxygen demand (BOD) were also determined. Metal inputs in the samples analysed appeared to be related to effluent discharges into the rivers. The suspended particles showed high concentrations (in mg kg(-1)) of zinc (62 600) and aluminium (559 000), while vegetation samples collected near rivers were heavily contaminated with iron (7680). The fishes examined were contaminated with chromium (1.5 mg kg(-1)). In general, the concentrations of nitrite, nitrate, chloride, phosphate and BOD in river water were lower than the maximum values established by the Brazilian Environmental Standards.

Chromium contamination in sediment, vegetation and fish caused by tanneries in the state of Minas Gerais, Brazil.

In order to evaluate the chromium contamination from tannery discharges into rivers in the State of Minas Gerais, Brazil, samples of fluvial sediment, vegetation and fish were collected and submitted to chemical analysis. The chromium content in the samples was measured by atomic absorption spectrophotometry. Metal inputs were related to effluent discharges into the rivers. High concentrations of chromium were found in samples when compared with controls. Sediment investigations indicated strong enrichment and high geoaccumulation indices, while chromium concentrations in the analyzed vegetation were higher than those normally found in these materials. Chromium levels in fish exceeded 35 times the Brazilian recommendation value for human intake.

Use of two short-term tests to evaluate the genotoxicity of river water treated with different concentration/extraction procedures.

The genotoxicity of river water samples was evaluated by the Salmonella mutagenicity assay and by the microscreen phage-induction assay. Different processes of sample treatment were compared using the following assays: different volumes of a non-concentrated sample (direct method); concentrated sample fractionated into portions with acid, basic and neutral activity (liquid-liquid extraction method); sample submitted to extraction of volatile substances (volatile extraction method). Samples that were positive to the Salmonella assay by the direct concentration method lost this activity after liquid-liquid extraction. This difference was related to the loss of substances that volatilize during the extraction process. The study of volatile product concentrates confirmed the role of these compounds in inducing activity present in some samples. The microscreen phage-induction assay proved to be a good screening assay for genotoxic compounds present in small concentration in environmental samples. We conclude that, whenever possible, samples should be treated by the direct method in different volumes to prevent the loss of genotoxic substances.