Levantamento da distribuição de equipamentos de diagnóstico por imagem e freqüência de exames radiológicos no Estado de São Paulo

OBJETIVO: Realizar um levantamento no Estado de São Paulo das informações referentes a equipamentos de diagnóstico por imagem e exames radiológicos. MATERIAIS E MÉTODOS: Essas informações foram obtidas através do Departamento de Informática do Sistema Único de Saúde (Datasus). A distribuição de equipamentos e a freqüência anual de exames foram analisadas considerando-se as diferentes regiões de saúde (Diretorias de Saúde) que compõem o Estado e suas respectivas populações. RESULTADOS: Os resultados obtidos apontam para diferenças regionais significativas, tanto em relação à distribuição de equipamentos como à freqüência de exames. Comparações com dados disponíveis de outros países indicam que pode haver demanda por parte da população em relação a exames de diagnóstico por imagem, principalmente no caso de mamografia, embora o acesso público a esses serviços tenha melhorado nos últimos anos. CONCLUSÃO: Estudos como este demonstram a importância da democratização das informações do sistema de saúde do País e contribuem para uma análise sistemática e objetiva de áreas específicas, servindo de referência para futuros trabalhos.

Tomografia computadorizada na avaliação da distribuição do tecido adiposo abdominal de ratos alimentados com rações hiperlipídicas após desnutrição neonatal

OBJETIVO: Descrever repercussões da ração suplementada com óleo de soja ou óleo de canola, por meio da tomografia computadorizada, na distribuição do tecido adiposo abdominal, após desmame de ratos desnutridos durante a lactação. MATERIAIS E MÉTODOS: Ratas lactantes submetidas a restrição alimentar (RA) em 50%, de acordo com o consumo das lactantes controles (C). Após o desmame, filhotes desnutridos receberam ração contendo 19% de óleo de soja (RA-soja 19%) ou óleo de canola (RA-canola 19%). Os filhotes do grupo controle receberam ração contendo 7% de óleo de soja (C-soja 7%). Aos 60 dias de idade, foram realizadas medidas corporais e das áreas de tecido adiposo abdominal por meio de tomografia computadorizada. Após sacrifício, tecido adiposo abdominal foi excisado e pesado. Os dados foram expressos como média ± erro-padrão da média, considerando o nível de significância de p < 0,05. RESULTADOS: Os grupos RA 19% desenvolveram similares comprimento, massa corporal e depósito de tecido adiposo visceral. Todas as avaliações realizadas foram significantemente menores em relação ao grupo C-soja 7%. Entretanto, na tomografia computadorizada, os grupos RA-soja 19% e RA-canola 19% apresentaram diferenças significativas da distribuição do tecido adiposo abdominal. CONCLUSÃO: A tomografia computadorizada mostrou que a distribuição de tecido adiposo, na cavidade abdominal, pode ser dependente do tipo de óleo vegetal na dieta.

Análise da distribuição espacial de dose absorvida em próton terapia ocular

OBJETIVO: Propõe-se avaliar os perfis de dose em profundidade e as distribuições espaciais de dose para protocolos de radioterapia ocular por prótons, a partir de simulações computacionais em código nuclear e modelo de olho discretizado em voxels. MATERIAIS E MÉTODOS: As ferramentas computacionais empregadas foram o código Geant4 (GEometry ANd Tracking) Toolkit e o SISCODES (Sistema Computacional para Dosimetria em Radioterapia). O Geant4 é um pacote de software livre, utilizado para simular a passagem de partículas nucleares com carga elétrica através da matéria, pelo método de Monte Carlo. Foram executadas simulações computacionais reprodutivas de radioterapia por próton baseada em instalações pré-existentes. RESULTADOS: Os dados das simulações foram integrados ao modelo de olho através do código SISCODES, para geração das distribuições espaciais de doses. Perfis de dose em profundidade reproduzindo o pico de Bragg puro e modulado são apresentados. Importantes aspectos do planejamento radioterápico com prótons são abordados, como material absorvedor, modulação, dimensões do colimador, energia incidente do próton e produção de isodoses. CONCLUSÃO: Conclui-se que a terapia por prótons, quando adequadamente modulada e direcionada, pode reproduzir condições ideais de deposição de dose em neoplasias oculares.

Avaliação quimiométrica da distribuição de metais pesados em composto de lixo urbano domiciliar

The main obstacle to the use of compost from urban waste in agriculture is the presence of heavy metals. Once in the soil, their effect is accumulative and they may contaminate crops and water. The present study reports the evaluation of the chemical distributions of Cu, Pb, Mn and Zn in three different sized fractions (unsieved, < 1,18mm and > 1,18mm) of compost, by means of a sequencial extraction procedure and a chemometric analysis of the total content of all metals in each fraction. The pattern recognition methods showed significant differences in total heavy metal contents for the different fractions. The finest one was the most contaminated. Meanwhile, this fraction presented lower amounts of metals in avaliable forms. This behavior can be attributed to the presence of metal particles in their elemental states in this fraction.

Caracterização ácido-base da superfície de espécies mistas da alga Spirulina através de titulação potenciométrica e modelo de distribuição de sítios discretos

Acid base properties of mixed species of the microalgae Spirulina were studied by potentiometric titration in medium of 0.01 and 0.10 mols L-1 NaNO3 at 25.0±0.10 C using modified Gran functions or nonlinear regression techniques for data fitting. The discrete site distribution model was used, permitting the characterization of five classes of ionizable sites in both ionic media. This fact suggests that the chemical heterogeneity of the ionizable sites on the cell surface plays a major role on the acid-base properties of the suspension in comparison to electrostatic effects due to charge-charge interactions. The total of ionizable sites were 1.75±0.10 and 1.86±0.20 mmolsg-1 in ionic media of 0.01 and 0.10 mols L-1 NaNO3, respectively. A major contribution of carboxylic groups was observed with an average 34 and 22% of ionizable sites being titrated with conditional pcKa of 4.0 and 5.4, respectively. The remaining 44% of ionizable sites were divided in three classes with averaged conditional pcKa of 6.9, 8.7 and 10.12, which may be assigned respectively to imidazolic, aminic, and phenolic functionalities.

Distribuição de coprostanol (5beta(H)-colestan-3beta-ol) em sedimentos superficiais da Baía de Guanabara: indicador da poluição recente por esgotos domésticos

A critical evaluation is presented on the use of faecal sterols for the identification of sewage contamination in Guanabara Bay. Sediments were collected from 8 stations in the bay selected as representative of different contamination levels. GC/MS determination of faecal sterols gave: coprostanol, 335 - 40000 ng g-1; coprostanone, 112-4136 ng g-1; cholesterol, 1407-7800 ng g-1; cholestanol, 2011 - 10900 ng g-1 and cholestanone, 655-7954 ng g-1. The observed concentration is in accordance with the presence of known pollution sources, however, concentration ratios of different sterols species produced unclear results evidently influenced by primary production and microbial processes.

Distribuição de metais e caracterização das constantes de troca entre espécies metálicas e frações húmicas aquáticas de diferentes tamanhos moleculares

In this work the metal distribution and exchange constants between metal species and aquatic humic fractions with different molecular sizes were studied. The aquatic humic substances (AHS) were extracted by XAD-8 resin from water sample collected from Itapitanguí river, São Paulo State, Brazil. The AHS were fractionated in six fractions with different molecular sizes (>100 - <5 kDa) and characterized by several techniques. Molar ratios H/C suggested higher aromaticity for fractions F1 and F6 whereas molar ratios C/N didn´t show any differences regarding the humification degree between the fractions. The UV-Vis absorbance a254/a436 ratio showed higher results for F4 and F5, probably by less condensed features. FTIR studies showed high similarity in the functional groups in the fractions. The highest percentage of traces of Co, Al, Fe, Mn, Cu, Zn and Ni (determined by ICP-AES) was preferably complexed by fractions F3 and F4 with a greater amount of dissolved organic carbon (DOC). In addition, the exchange constants, determined by ultrafiltration method, showed complexes AHS-Fe and AHS-Al with higher stability than complexes AHS-Co in all fractions.

Distribuição de compostos organoclorados nas águas e sedimentos da bacia do rio Piracicaba/SP - Brasil

The great utilization of synthetic and persistent xenobiotic cumulative compounds is the main causes of the deterioration of aquatic ecosystems. The one of objective of this work was the determination of the organochlorine levels in the Piracicaba river basin, situated at the center of São Paulo state. Four PCBs congeners, PCP and HCB were determined by GC-ECD in two different matrices: water and sediments. The pattern of the compound distribution indicated a dominance of PCP, HCB and PCB-200. The results indicated contamination in the sampling points located in Campinas, Piracicaba, Santa Bárbara d'Oeste and Sumaré cities.

Distribuição de metais pesados em sedimentos do sistema estuarino da Ilha de Vitória-ES

Heavy-metal concentration in sediment is an important parameter for identifying pollution sources and assessing pollution levels in aquatic ecosystems. In this context, the present study aimed at determining concentrations of heavy metals in sediments from the Vitória estuarine system, Brazil. Twenty nine stations were surveyed to assess the spatial distribution of heavy metals. The metals for silt-clay fractions (<63 µm) were analyzed through atomic absorption spectrometry. A discriminant analysis segregated the stations in four groups representing four areas within the estuarine system. The Espírito Santo Bay showed the lowest metal concentrations, while the Vitória harbor canal showed the highest. We concluded that concentrations of heavy metals reflect natural conditions and the contribution of human activities from sewage and industrial effluents. It was not possible to directly associate metal concentrations to specific pollution sources.

Distribuição de mercúrio total como indicador de poluição urbana e industrial na costa brasileira

The monitoring of the pollution status of the Brazilian coast is hampered by the lack of a consistent environmental indicator. We propose Hg as an environmental proxy to anthropogenic pollution of coastal regions due to its absence in the Brazilian geology, its ubiquity in anthropogenic effluents, and its toxicity. Available data suggest Hg "backgrounds" in coastal sediments of 1-10 ng g-1, in the East and 15-30 ng g-1 in the South. We suggest short sediment cores to establish these values estimating a geo-accumulation index to compare all areas. The distribution of index values showed the majority of southern coast at least moderately contaminated whereas many eastern areas are still pristine.

Determinação do coeficiente de distribuição (Kd) de benzo(a)pireno em solo por isotermas de sorção

Leaking of diesel oil from gas stations is frequent in Brazil. The presence of polycyclic aromatic hydrocarbons (PAHs), which are highly toxic is an indication of contamination by heavy hydrocarbons from diesel oil. Here were present the determination of the distribution coefficient (Kd) of benzo(a)pyrene (the most carcinogenic of the PAHs) in tropical soils using the sorption isotherm model. The sorption curves acquired for benzo(a)pyrene were of the S-type, probably due to the water/methanol experimental conditions. The sorption curves allowed calculation of the distribution coefficient (Kd). The experimental Kd values were lower than those calculated from literature Koc values (partition coefficient normalized by organic carbon), due mainly to the cosolvency effect and the percentage of organic matter and clay in soil.

Desempenho físico-químico de metais e estruturas de concreto de redes de distribuição de energia: estudo de caso na região de Manaus

The influence of natural aging furthered by atmospheric corrosion of parts of electric transformers and materials, as well as of concrete poles and cross arms containing corrosion inhibitors was evaluated in Manaus. Results for painted materials, it could showed that loss of specular gloss was more intensive in aliphatic polyurethane points than in acrylic polyurethane ones. No corrosion was observed for metal and concrete samples until 400 days of natural aging. Corrosion in steel reinforcement was noticed in some poles, arising from manufacturing faults, such as low cement content, water/cement ratio, thin concrete cover thickness, etc. The performance of corrosion inhibitors was assessed by many techniques after natural and accelerated aging in a 3.5% saline aqueous solution. The results show the need for better chemical component selection and its concentration in the concrete mixture.

Distribuição espacial de ferro, cobre e chumbo em sedimentos de manguezal em um gradiente de degradação na Baía de Guanabara (Estado do Rio de Janeiro)

Iron, copper and lead distribution was evaluated in sediment cores from a disturbed mangrove area in Guanabara Bay: a core from a seaward site where mangrove vegetation was removed ~20 yr before sampling (MD); a core from an intermediate site with dead vegetation, apparently due to insect attack (MP), and a core from a landward site with living vegetation (MV). Metal concentrations showed increasing values seaward while organic matter content showed an inverse trend, displaying a negative correlation with metals. This unusual correlation indicates opposite sources, since metals come from the bay and the main OM origin is probably degraded mangrove vegetation. Plant cover loss seems to be a critical factor affecting metal accumulation, particularly due to changes in OM input.

Distribuição de mercúrio em diferentes solos da Bacia do médio Rio Negro-AM: influência da matéria orgânica no ciclo biogeoquímico do mercúrio

Soils play an important role in the biogeochemical cycle of mercury as a sink for and source of this metallic species to atmospheric and hydrological compartments. In the study reported here, various types of soil were evaluated to ascertain the influence of parameters such as pH, organic matter content, Fe, Al, sand, silt, clay, C/H, C/N, C/O atomic ratios, and cation exchange capacity on the distribution of Hg in Amazonia's mid-Negro River basin. The data obtained were interpreted by multivariate exploratory analyses (hierarchical cluster analysis and principal component analysis), which indicated that organic matter plays an important role in mercury uptake in the various soils studied. The soils in floodable areas were found to contain 1.5 to 2.8-fold higher Hg concentrations than those in non-floodable areas. Since these soils are flooded almost year-round, they are less available to participate in redox processes at the soil/atmosphere interface. Hence, floodable areas, which comprise humic-rich soils, accumulate more mercury than non-floodable soils, thus playing an important role in the biogeochemical cycle of Hg in Amazonia's mid-Negro River basin.

Distribuição de selênio em organismos marinhos da Baía de Guanabara/ RJ

The study assessed selenium concentrations in the muscle tissues and liver samples of three fish species and in the soft tissues of a mussel species. The samples were analyzed by GF-AAS using Zeeman background correction. Selenium in the muscle samples was higher in carnivorous fish. The liver of all studied fish species presented higher selenium concentrations than the muscle. The fish species presented a high positive correlation between their total length and selenium concentration. A significant correlation was observed between the selenium concentration in the mussel soft tissues and the condition index.