Obtenção e caracterização de um compósito de matriz polimérica com carga de resíduos vegetal proveniente do sabugo de milho

The feasibility of using the corn cob to obtain a polymer matrix composite was studied. To obtain the bran, corncob passed the drying process in a solar dryer, and was subsequently triturated in forage and to obtain the different particle sizes, by sieving. Three different grain sizes were used: fine particles (FP) size between 0,10 and 2mm; sized particles (PM) with sizes between 2,10 and 3,35 mm; large particles (PG) sizes between 3,45 and 4,10 mm. Using 20% of residue relative to the resin, the test samples were constructed for characterization of the composite, taking into account thermal and mechanical parameters. The main advantage of the proposed composite is that it has a low density, below the relative resin, about 1.06 kg / m³ for the PG. The composite showed a mechanical behavior less than of the resin to the grain sizes and for all formulations studied. Showed better results for the bending, reaching 25.3 MPa for the PG. The composite also showed be feasible for thermal applications, with thermal conductivity less than 0.21 W / m, ranking as insulation. In terms of homogeneity of the mixture, the most viable grain size is the PF, which also showed improved aesthetics and better processability. This composite can be used to make structures that do not require significant mechanical strength, such as tables, chairs, planks, and solar and wind prototypes, such as ovens and cookers and turbines blades.

Obtenção e caracterização de um compósito de matriz polimérica com carga de resíduos vegetal proveniente do sabugo de milho

The feasibility of using the corn cob to obtain a polymer matrix composite was studied. To obtain the bran, corncob passed the drying process in a solar dryer, and was subsequently triturated in forage and to obtain the different particle sizes, by sieving. Three different grain sizes were used: fine particles (FP) size between 0,10 and 2mm; sized particles (PM) with sizes between 2,10 and 3,35 mm; large particles (PG) sizes between 3,45 and 4,10 mm. Using 20% of residue relative to the resin, the test samples were constructed for characterization of the composite, taking into account thermal and mechanical parameters. The main advantage of the proposed composite is that it has a low density, below the relative resin, about 1.06 kg / m³ for the PG. The composite showed a mechanical behavior less than of the resin to the grain sizes and for all formulations studied. Showed better results for the bending, reaching 25.3 MPa for the PG. The composite also showed be feasible for thermal applications, with thermal conductivity less than 0.21 W / m, ranking as insulation. In terms of homogeneity of the mixture, the most viable grain size is the PF, which also showed improved aesthetics and better processability. This composite can be used to make structures that do not require significant mechanical strength, such as tables, chairs, planks, and solar and wind prototypes, such as ovens and cookers and turbines blades.

Eficiência e razão de hedge: uma análise dos mercados futuro brasileiros de boi, café, etanol, milho e soja

This research aims to investigate the Hedge Efficiency and Optimal Hedge Ratio for the future market of cattle, coffee, ethanol, corn and soybean. This paper uses the Optimal Hedge Ratio and Hedge Effectiveness through multivariate GARCH models with error correction, attempting to the possible phenomenon of Optimal Hedge Ratio differential during the crop and intercrop period. The Optimal Hedge Ratio must be bigger in the intercrop period due to the uncertainty related to a possible supply shock (LAZZARINI, 2010). Among the future contracts studied in this research, the coffee, ethanol and soybean contracts were not object of this phenomenon investigation, yet. Furthermore, the corn and ethanol contracts were not object of researches which deal with Dynamic Hedging Strategy. This paper distinguishes itself for including the GARCH model with error correction, which it was never considered when the possible Optimal Hedge Ratio differential during the crop and intercrop period were investigated. The commodities quotation were used as future price in the market future of BM&FBOVESPA and as spot market, the CEPEA index, in the period from May 2010 to June 2013 to cattle, coffee, ethanol and corn, and to August 2012 to soybean, with daily frequency. Similar results were achieved for all the commodities. There is a long term relationship among the spot market and future market, bicausality and the spot market and future market of cattle, coffee, ethanol and corn, and unicausality of the future price of soybean on spot price. The Optimal Hedge Ratio was estimated from three different strategies: linear regression by MQO, BEKK-GARCH diagonal model, and BEKK-GARCH diagonal with intercrop dummy. The MQO regression model, pointed out the Hedge inefficiency, taking into consideration that the Optimal Hedge presented was too low. The second model represents the strategy of dynamic hedge, which collected time variations in the Optimal Hedge. The last Hedge strategy did not detect Optimal Hedge Ratio differential between the crop and intercrop period, therefore, unlikely what they expected, the investor do not need increase his/her investment in the future market during the intercrop

Atividades Biológicas De Xilana De Sabugo De Milho

The corn cob is an agricultural by-product still little used, this in part due to the low knowledge of the biotechnological potential of their molecules. Xylan from corn cobs (XSM) is a polysaccharide present in greater quantity in the structure of plant and its biotechnology potential is little known. This study aimed to the extraction, chemical characterization and evaluation of biological activities of xylan from corn cobs. To this end, corncobs were cleaned, cut, dried and crushed, resulting in flour. This was subjected to a methodology that combines the use of alkaline conditions with waves of ultrasound. After methanol precipitation, centrifugation and drying was obtained a yield of 40% (g/g flour). Chemical analysis indicated a high percentage of polysaccharides in the sample (60%) and low contamination by protein (0.4%) and phenolic compounds (> 0.01%). Analysis of monosaccharide composition indicated the presence of xylose:glucose:arabinose:galactose:mannose:glucuronic acid in a molar ratio 50:20:15:10:2.5:2.5. The presence of xylan in the sample was confirmed by nuclear magnetic resonance (¹H and ¹³C) and infrared spectroscopy (IR). Tests were conducted to evaluate the antioxidant potential of XSM. This showed a total antioxidant capacity of 48.45 EAA/g sample. However, did not show scavenging activity of superoxide and hydroxyl radical and also reducing power. But, showing a high capacity chelating iron ions with 70% with about 2 mg/mL. The ability to XSM to influence cell proliferation in culture was also evaluated. This polymer did not influence the proliferation of normal fibroblast cells (3T3), however, decreased the rate of proliferation of tumor cells (HeLa) in a dose-dependent, reaching an inhibition of about 50% with a concentration around 2 mg/mL. Analyzing proteins related to cell death, by immunoblotting, XSM increases the amount of Bax, Bcl-2 decrease, increase cytochrome c and AIF, and reduce pro-caspase-3, indicating the induction of cell death induced apoptosis dependent and independent of caspase. XSM did not show anticoagulant activity in the PT test. However, the test of activated partial thromboplastin time (aPTT), XSM increased clotting time at about 5 times with 600 μg of sample compared with the negative control. The presence of sulfate on the XSM was discarded by agarose gel electrophoresis and IR. After carboxyl-reduction of XSM the anticoagulant activity decreased dramatically. The data of this study demonstrate that XSM has potential as antioxidant, antiproliferative and anticoagulant compound. Future studies to characterize these activities of XSM will help to increase knowledge about this molecule extracted from corn and allow their use in functional foods, pharmaceuticals and chemical industries.

Efeito inseticida de vicilinas isoladas de sementes de erythrina velutina em condições de semi-campo para moscas das frutas (ceratitis capitata)

Chitin-binding vicilins from legume seeds (Erythrina velutina. Canavalia ensiformes and Phaseolus vulgares) were isolated by ammonium sulfate followed by affinity chromatography on a chitin column. Effect of these vicilins on female adults of Ceratitis capitata was examined by bioassay and in a semi-field assay model. Mechanism of action of the vicilins was determined by in vivo digestibility and chitin affinity. Among the tested vicilins, E. velutina when added to diet caused strong effect on mortality at 10% dose. This insecticidal property was tested in a semi-field assay which showed the same effect observed in laboratory conditions, where doses of 10% and 15% were lethal to female adults of C. capitata. These deleterious effects were not only associated to the binding to chitin structures present in peritrophic membrane, but principally to its low digestibility in the C. capitata digestive tract. This fact was confirmed because chiting binding proteins as WGA and the other tested vicilins were not toxic to female adults of C. capitata due susceptibility of these proteins to digestive enzymes of the insects. By other side EvV was more resistant to digestive enzymes, causing deleterious effects on female adults of C. capitata. These results showed that EvV may be part of the pest management programs or an alternative in plant improvement program in the population control of this fruticulture pest

Influência da vermiculita expandida na resistência à compressão e reologia de pastas cimentantes de poços de petróleo

Several problems related to the loss of hydraulic seal in oilwells, causing gas migration and/or contamination of the production zone by water, have been reported. The loss of the hydraulic seal is a consequence of cracks which can be occasioned either by the invasion of gas during the wait on cement or by the expansion of the casing causing the fracture of the cement sheath. In case of the pressure of the formation is higher than the pressure in the annulus, gas can migrate into the slurry and form microannulus, which are channels where gas migrates after the cement is set. Cracks can be also occasioned by the fracture of the cement sheath when it does not withstand the thermal and dynamic loads. In reservoirs where the oil is heavy, steam water injection operation is required in order to get the oil flowing. This operation increases the temperature of the casing, and then it expands and causes the fracture of the cement sheath in the annulus. When the failures on the cement are detected, remedial cementing is required, which raise costs caused by the interventions. Once the use of cement in the construction civil sector is older than its use in the petroleum sector, it is common to bring technologies and solutions from the civil construction and apply them on the petroleum area. In this context, vermiculite, a mineral-clay widely encountered in Brazil, has been used, on its exfoliated form, in the civil construction, especially on the manufacture of lights and fireproof concretes with excellent thermal and acoustical properties. It has already been reported in scientific journals, studies of the addition of exfoliated vermiculite in Portland cements revealing good properties related to oilwell cementing operations. Thus, this study aimed to study the rheological behavior, thickening time, stability and compressive strength of the slurries made of Portland cement and exfoliated vermiculite in 5 different compositions, at room temperature and heated. The results showed that the compressive strength decreased with the addition of exfoliated vermiculite, however the values are still allowed for oiwell cementing operations. The thickening time of the slurry with no exfoliated vermiculite was 120 min and the thickening time of the slurry with 12 % of exfoliated vermiculite was 98 min. The stability and the rheological behavior of the slurries revealed that the exfoliated vermiculite absorbed water and therefore increased the viscosity of the slurries, even though increasing the factor cement-water. The stability experiment carried out at 133 ºF showed that, there was neither sedimentation nor reduction of the volume of the cement for the slurry with 12 % of exfoliated vermiculite. Thus, the addition of exfoliated vermiculite accelerates the set time of the cement and gives it a small shrinkage during the wait on cement, which are important to prevent gas migration

Desenvolvimento de bioblendas poliméricas a partir de gelatina bovina e de tilápia com amido de milho

The natural raw materials acquired special importance beside the mineral raw materials with the need for using alternative sources to oil, because they can be used to produce biopolymers. Gelatin, produced from the denaturation of collagen, and starch, an abundant polysaccharide in various plants, are examples of biopolymers which have several technological applications, especially in films. The objective of this work is to produce polymeric bioblends with gelatin and corn starch using two types of gelatin: commercial bovine gelatin and gelatin produced from mechanically separated flesh of tilapia (Oreochromis niloticus). For the extraction of tilapia gelatin 3 distinct pretreatments, followed by extraction in distilled water under heating were performed. The properties of gelatin extracted were similar to bovine gelatin, and the differences can be explained by the difference in extraction processes and sources. Blends of commercial gelatin and starch were produced in an internal mixer from a Haake torque rheometer, to study the behavior of the gelatin mixture with starch, thus, the same compositions were processed by twin screw extrusion, to define the mixing parameters. Subsequently, the extrusion of blends of tilapia gelatin and corn starch was carried out in the same twin screw extruder. The physico-chemical, rheological and morphological properties of the blends with thermoplastic starch and gelatin were studied. It was found that various properties vary linearly with increasing concentration of the components. The blends produced are immiscible, and among the two gelatins, tilapia gelatin showed a better interfacial adhesion with the corn starch. Regarding the morphology, gelatins formed the dispersed phase in all compositions studied, even in compositions rich in starch. Can be concluded that the procedure for tilapia gelatin extraction is feasible and advantageous, and the increasing in its scale to a reactor of 30 liters is possible, with a satisfactory yield. The bioblends of bovine gelatin/corn starch and tilapia gelatin/corn starch were successfully produced, and the processing conditions were appropriate

Incorporação de resíduo cerâmico para prevenção da retrogressão da resistência de cimentos de poços de petróleo submetidos à injeção de vapor

Steam injection is the most used thermal recovery method of oil nowadays because of the high degree of development of the technique that allows high recovery factors. However, injection of superheated steam into the reservoir affects the entire structure of the well, including the cemented layer that presents a retrogression of compressive strength and increases the permeability due to formation of more crystalline and denser phases at temperatures above 110 °C. These changes result in failures in the cement that favor the entrance of formation fluids into the annulus space resulting in unsafe operations and restrictions in the economic life of the well. But the strength retrogression can be prevented by partial replacement of cement by silica-based materials that reduce the CaO/SiO2 ratio of cement slurries changing the trajectory of the reactions, converting those deleterious phases in phases with satisfactory mechanical strength and permeability. The aim of this study was to evaluate the behavior of a ceramic waste material rich in silica in partial and total substitution of a mineral additive used to fight the strength retrogression of cement slurries subjected to high temperatures. The evaluation was made by compression, X-ray diffraction (XRD) and thermogravimetry (TG/DTG). The samples were submitted to a cycle of low temperature (38 °C) for 28 days and a cycle of low temperature followed by exposure to 280 ºC and 1000 psi by 3 days. The results showed that slurries with additions of up to 30% of the waste material are not enough to prevent the strength retrogression, while slurries with additions of the waste material combined with silica flour in various proportions produced hydrated products of low Ca/Si ratios that maintained the compressive strength at satisfactory levels

Avaliação da corrosão em dutos por técnica gravimétrica e de resistência elétrica

With the increasing of demand for natural gas and the consequent growth of the pipeline networks, besides the importance of transport and transfer of oil products by pipeline, and when it comes to product quality and integrity of the pipeline there is an important role regarding to the monitoring internal corrosion of the pipe. This study aims to assess corrosion in three pipeline that operate with different products, using gravimetric techniques and electrical resistance. Chemical analysis of residues originated in the pipeline helps to identify the mechanism corrosive process. The internal monitoring of the corrosion in the pipelines was carried out between 2009 and 2010 using coupon weight loss and electrical resistance probe. Physico-chemical techniques of diffraction and fluorescence X-rays were used to characterize the products of corrosion of the pipelines. The corrosion rate by weight loss was analyzed for every pipeline, only those ones that has revealed corrosive attack were analyzed located corrosion rate. The corrosion potential was classified as low to pipeline gas and ranged from low to severe for oil pipelines and the pipeline derivatives. Corrosion products were identified as iron carbonate, iron oxide and iron sulfide

Efeito da adição de cargas minerais leves na resistência mecânica de grautes para cimentação de poços offshore

The preparation of cement slurries for offshore well cementing involves mixing all solid components to be added to the mixing water on the platform. The aim of this work was to study the formulation of pre-prepared dry mixtures, or grouts, for offshore oilwell cementing. The addition of mineral fillers in the strength of lightweight grouts applied for depths down to 400 m under water depths of 500 m was investigated. Lightweight materials and fine aggregates were selected. For the choice of starting materials, a study of the pozzolanic activity of low-cost fillers such as porcelain tile residue, microsilica and diatomaceous earth was carried out by X-ray diffraction and mechanical strength tests. Hardened grouts containing porcelain tile residue and microsilica depicted high strength at early ages. Based on such preliminary investigation, a study of the mechanical strength of grouts with density 1.74 g/cm3 (14.5 lb/gal) cured initially at 27 °C was performed using cement, microsilica, porcelain tile residue and an anti-foaming agent. The results showed that the mixture containing 7% of porcelain tile residue and 7% of microsilica was the one with the highest compressive strength after curing for 24 hours. This composition was chosen to be studied and adapted for offshore conditions based on testes performed at 4 °C. The grout containing cement, 7% of porcelain tile residue, 7% of active silica and admixtures (CaCl2), anti-foaming and dispersant resulted satisfactory rheology and mechanical strength after curing for 24 hours of curing

Avaliação do potencial de formigas (Hymenoptera: formicidae) como vetores mecânicos de bactérias do gêneroSstaphylococcus no ambiente hospitalar.

In a hospital environment, these bacteria can be spread by insects such as ants, which are characterized by high adaptability to the urban environment. Staphylococcus is a leading cause of hospital infection. In Europe, Latin America, USA and Canada, the group of coagulase negative staphylococci (CoNS) is the second leading cause of these infections, according to SENTRY (antimicrobial surveillance program- EUA). In this study, we investigated the potential of ants (Hymenoptera: Formicidae) as vehicle mechanics of Staphylococcus bacteria in a public hospital, in Natal-RN. The ants were collected, day and night, from June 2007 to may 2008, in the following sectors: hospitals, laundry, kitchen, blood bank. The ants were identified according to the identification key of Bolton, 1997. For the analysis of staphylococci, the ants were incubated in broth Tryptic Soy Broth (TSB) for 24 hours at 35 º C and then incubated on Mannitol Salt Agar. The typical colonies of staphylococci incubated for 24 hours at 35 ° C in Tryptic Soy Agar for the characterization tests (Gram stain, catalase, susceptibility to bacitracin and free coagulase). The identification of CoNS was performed through biochemical tests: susceptibility to novobiocin, growth under anaerobic conditions, presence of urease, the ornithine decarboxylation and acid production from the sugars mannose, maltose, trehalose, mannitol and xylose. The antimicrobial susceptibility examined by disk-diffusion technique. The technique of Polymerase Chain Reaction was used to confirm the presence of mecA gene and the ability to produce biofilm was verified by testing in vitro using polystyrene inert surface, in samples of resistant staphylococci. Among 440 ants, 85 (19.1%) were carrying coagulase-negative staphylococci (CoNS) of the species Staphylococcus saprophyticus (17), Staphylococcus epidermidis (15), Staphylococcus xylosus (13), Staphylococcus hominis hominis (10), Staphylococcus lugdunensis (10), Staphylococcus warneri (6), Staphylococcus cohnii urealyticum (5), Staphylococcus haemolyticus (3), Staphylococcus simulans (3), Staphylococcus cohnii cohnii (2), and Staphylococcus capitis (1). No Staphylococcus aureus was found. Among the isolates, 30.58% showed resistance to erythromycin. Two samples of CoNS (2.35%), obtained from the ant Tapinoma melanocephalum collected in the post-surgical female ward, S. Hominis hominis and S. lugdunensis harbored the mecA gene and were resistant to multiple antibiotics, and the specie S. hominis hominis even showed to be a biofilm producer. This study proves that ants act as carriers of multidrug-resistant coagulase-negative Staphylococci and biofilm producers and points to the risk of the spreading of pathogenic microorganisms by this insect in the hospital environment

Comportamento adaptativo de Lutzomyia longipalpis (Diptera: Psychodidae) às áreas urbanas da cidade de Teresina-PI.

The sand fly Lutzomyia longipalpis (Diptera: Psychodidae) is currently appointed as the main vector of visceral leishmaniasis in the Americas. The growth of cities in areas originally endemics to American Visceral Leishmaniasis (AVL) resulted in the spread of the disease at the same time that observed the adaptation of this species to the urban environment.Changes in behavior of L.longipalpis that enabled the adapt to increasing losings of biodiversity, as well as the frequent exposure of the vector to insecticides evident in urban areas, could justify the increasing population of the species and consequently the spread of disease for these environments .Thus, we selected sixty houses spread among three areas with increasing stages of occupation of an area endemic for AVL in Teresina-PI. We evaluated the correlation between the density of L.longipalpis captured and different aspects, such as population density of animals, vegetation cover and socio-economic aspects in each house. In addition to the correlations, the feeding preference of the vector between the predominant plant species in the neighborhoods, as well as the presence of metabolic mechanisms of resistance among the captured insects were tested. The results showed that over the growing occupations, represented by three areas, L.longipalpis demonstrate its adaptive nature through an apparent opportunistic behavior in relation to sources of carbohydrates and blood. On the evolutionary point of view, this behavior may have favored its vector competence in urban areas among the limited presence of food sources, as well as in various environments encountered.

Resistência da artéria carótida e autônima funcional em mulheres idosas

High carotid artery resistance indices in the elderly arise mainly as a result of harmful daily lifestyle behavior and poor eating habits. The aim of this multidisciplinary study was to assess and correlate carotid artery resistance and functional autonomy in elderly women. A descriptive, exploratory cross-sectional study was conducted with a sample comprising 27 women, enrolled in pastoral programs in the city of Teresina, Brazil. Carotid artery resistance was assessed by a high-resolution Doppler ultrasound device and functional autonomy was evaluated through five protocol tests of the Latin American Development Group for the Elderly (GDLAM), simulating activities of daily life. The data were analyzed by the Shapiro-Wilk test and the correlation by Spearman s test, considering a p-value of <0.05. The sample consisted of women with mean age and standard deviation of (68.67 ± 4.52) years, respectively and carotid resistance index of (0.71 ± 0.07). The general index value of functional autonomy classified the elderly of the study group as weak in the performance of activities of daily living (30.46 ± 6.31). The general index of functional autonomy showed a high level of sedentary behavior in the group studied (p < 0.01). The sample was classified as weak in the performance of activities of daily life. The correlation coefficient between the carotid resistance index and the general GDLAM index was r = 0.998 and p = 0.000, showing a significant correlation. The elderly women assessed had a high carotid artery resistance index and low functional autonomy; a positive correlation was found between the dependent variables studied. To perform this study we formed a team composed of a nurse, who helped in organizing the sample and performing the examinations; a radiologist, who conducted the Doppler examinations; an angiologist, who collaborated in interpreting examination data; in addition to two physical education professors and two physical therapists, who applied the functional autonomy tests and conducted the 34 research along elderly health lines, contributing thus to the multidisciplinary character, fundamental for carrying out the study

Resistotipagem e transferência genética de plasmídios de resistência entre coliformes e vibrios potencialmente patogênicos para o homem isolados de camarão (litopenaeus vannamei) comercializado em Natal-Rio Grande do Norte

Cinquenta amostras de camarão fresco e refrigerado (Litopenaeus vannamei) foram coletadas em diferentes pontos de comercialização na cidade de Natal RN. As amostras foram maceradas em um gral estéril e 25 gramas semeadas em 225mL de APA contendo 1% de NaCl e 25g em 225mL de CL incubadas a 35ºC - 24 horas. O crescimento em APA foi semeado em placas de Ágar TCBS, incubadas a 35ºC-24h para isolamento de Vibrio e Aeromonas. O crescimento do CL foi semeado em Agar EAM, para isolamento de coliformes. Dos 102 isolados, 91 (89,2%) pertenciam ao gênero Vibrio e 11 (10,8%) ao gênero Aeromonas, com predominância de V. cholerae não O1/não O139, V. alginolyticus, V. carchariae e V. parahaemolyticus K- e A. veronii biogrupo sobria , A. jandaei, A. schubertii, A. veronii biogrupo veronii e A. hydrophila. A menor eficiência entre os antimicrobianos foi da AMP (57,8% de resistência) seguida da AMK (29,4%) e TCY (21,6%). As 39 cepas de Vibrio e Aeromonas multirresistentes se distribuíram em 10 perfis distintos, sendo que um revelou cinco marcos (AMP, CHL, NIT, SXT e TCY) em um isolado de V. carchariae de camarão, adquirido em supermercados. O índice MAR, nas 39 cepas variou de 0,28 a 0,42, sugerindo que são de risco na transferência e difusão da resistência na cadeia alimentar. Após a cura plasmidial pelo tratamento com AO de 24 cepas multirresistentes e com resistência intermediária de víbrio e aeromonas escolhidas aleatoriamente, 13 perderam totalmente a resistência e 7 perderam parcialmente, sendo que o maior percentual de perda da resistência ocorreu nas cepas de V. cholerae não O1 e não O139 (6 cepas), se concentrando nos marcos de resistência a AMP (13), AMK (11), TCY(8) e CIP(3). Os resultados da conjugação realizada entre amostras de Vibrio xvi curadas e a E. coli K12C600 demonstraram que 78,5% das culturas de Vibrio testadas revelaram capacidade de transferência para o gene que confere resistência a AMP e 28,5% para a TCY. Dos coliformes, E. coli foi a mais frequente, seguida de Citrobacter spp, isoladas em 40,3% e 27,5% das amostras respectivamente. AMP foi o antimicrobiano menos eficaz, seguido de TCY. As 11 cepas multirresistentes se distribuíram em 9 perfis distintos, um deles constituído de cinco marcos (AMP, NIT, TCY, CHL, SXT), albergados em uma cepa de Klebsiella spp, oriunda de camarão adquirido em supermercado, similar ao resultado obtido em V. carchariae. Conclui-se que, os camarões marinhos frescos e refrigerados, comercializados em Natal-RN evidenciaram contaminação com coliformes, víbrios e aeromonas multirresistentes a antimicrobianos comumente utilizados na terapia médica e veterinária, e que, possivelmente, a transferência de genes de resistência entre bactérias se constitui um sério problema de saúde pública

Análise do óxido nítrico, perfil lipídico, resistência arterial e capacidade funcional de idosas submetidas a um treinamento aquático

A prática regular de exercício físico possibilita redução dos efeitos das disfunções hormonais e envelhecimento biológico natural que promovem desajustes hemodinâmicos, vasculares e músculo-esqueléticos, principalmente na população feminina no período pós-menopausa. Nesta fase da vida, o exercício aquático representa mais do que uma forma de ajuste funcional, é uma forma de manutenção de independência para as atividades da vida diária (AVD s) e melhoria na qualidade de vida. Este estudo teve como objetivo avaliar as modificações adquiridas pela prática regular de um programa de exercício aquático concorrente de intensidade moderada no nível de óxido nítrico (ON), no índice de resistividade arterial (IR), no perfil lipídico, na capacidade funcional e na qualidade de vida de idosas. A amostra foi formada por idosas (60 a 80 anos) selecionadas por randomização, por sorteio simples divididas em grupo controle e grupo de intervenção as quais foram submetidas a um programa de exercícios aquáticos proposto inicialmente em projeto piloto, por 12 semanas (n=34) e o ensaio clínico teve duração de 16 semanas (n=40). Foi coletada amostra sanguínea das idosas e avaliado o perfil lipídico pelo método enzimático com kit Labtest e o ON por medida indireta a partir da concentração de nitrito no sobrenadante das células em cultura em leitor de ELISA. A avaliação das artérias carótidas e vertebrais foi feita utilizando o método de ultra-som Doopler. A capacidade funcional foi avaliada por quatro testes que simulam atividades da vida diária que são: caminhar 10 metros (C10m), levantar da posição sentada (LPS), levantar da cadeira e locomover-se pela casa (LCLC) e o de levantar-se da posição decúbito ventral (LPDV). No estudo piloto foi avaliado o índice geral de autonomia funcional (IG) e a qualidade de vida através do questionário WHOQOL-100. Empregou-se a análise de variância (ANOVA) com medidas repetidas nos fatores grupo (GH e GC) e tempo (pré e pós-teste) para as comparações intra e intergrupos nas variáveis seguida do post hoc de Scheffé. Utilizou-se o teste de correlação de Pearson e adotado o valor de p<0,05 para a significância estatística. Houve aumento do ON circulante, redução nos índices de resistividade arterial, melhoria significativa nos níveis de colesterol e triglicérides e ganho na capacidade funcional das idosas após a intervenção. Existiu correlação inversa entre a resistividade da artéria vertebral direita (VERTD) e níveis de ON e entre a VERTD e os níveis plasmáticos de HDL, assim como entre estes e o teste C10m nas idosas em estudo. Não houve modificações significativas na qualidade de vida das idosas. Em conclusão, o programa de exercício proposto foi capaz de oferecer melhorias funcionais, aumentar o nível de óxido nítrico circulante, diminuindo a resistência arterial promovendo modificações no perfil lipídico de idosas