Influência das tensões tectônicas na permeabilidade da formação Açu - Bacia Potiguar

The behavior of the fluid flux in oil fields is influenced by different factors and it has a big impact on the recovery of hydrocarbons. There is a need of evaluating and adapting the actual technology to the worldwide reservoirs reality, not only on the exploration (reservoir discovers) but also on the development of those that were already discovered, however not yet produced. The in situ combustion (ISC) is a suitable technique for these recovery of hydrocarbons, although it remains complex to be implemented. The main objective of this research was to study the application of the ISC as an advanced oil recovery technique through a parametric analysis of the process using vertical wells within a semi synthetic reservoir that had the characteristics from the brazilian northwest, in order to determine which of those parameters could influence the process, verifying the technical and economical viability of the method on the oil industry. For that analysis, a commercial reservoir simulation program for thermal processes was used, called steam thermal and advanced processes reservoir simulator (STARS) from the computer modeling group (CMG). This study aims, through the numerical analysis, find results that help improve mainly the interpretation and comprehension of the main problems related to the ISC method, which are not yet dominated. From the results obtained, it was proved that the mediation promoted by the thermal process ISC over the oil recovery is very important, with rates and cumulated production positively influenced by the method application. It was seen that the application of the method improves the oil mobility as a function of the heating when the combustion front forms inside the reservoir. Among all the analyzed parameters, the activation energy presented the bigger influence, it means, the lower the activation energy the bigger the fraction of recovered oil, as a function of the chemical reactions speed rise. It was also verified that the higher the enthalpy of the reaction, the bigger the fraction of recovered oil, due to a bigger amount of released energy inside the system, helping the ISC. The reservoir parameters: porosity and permeability showed to have lower influence on the ISC. Among the operational parameters that were analyzed, the injection rate was the one that showed a stronger influence on the ISC method, because, the higher the value of the injection rate, the higher was the result obtained, mainly due to maintaining the combustion front. In connection with the oxygen concentration, an increase of the percentage of this parameter translates into a higher fraction of recovered oil, because the quantity of fuel, helping the advance and the maintenance of the combustion front for a longer period of time. About the economic analysis, the ISC method showed to be economically feasible when evaluated through the net present value (NPV), considering the injection rates: the higher the injection rate, the higher the financial incomes of the final project

Diagnóstico da possível influência da atividade petrolífera em sedimentos de fundo da Bacia Piranhas-Açu, região Baixo Açu/RN

It is located in an area of increasing oil exploration, the region of the Lower Açu is at the mercy of a possible pollution generated by this economic activity, which includes various chemical substances harmful to health, such as metals. This thesis aims to, diagnose the areas of River Piranhas-Açu, a region of the Lower Açu, which are polluted by traces factors and more. In this study, it was determined the concentration of the chemica elements Al, CD, Cr, Cu, Fe, Mn, Ni, P, Pb, V and Zn, through the technique of ICP-OES analysis and the size of sediments and their contents organic matter. Were mapped by GPS, 12 points from collections. The interpretations of the results, together associating that allowed pollution to a possible contamination by oil activity. The results showed tha some regions have low concentrations of cadmium, lead, copper, manganese and zinc unable to promote damage to human health. However, there are places where the concentrations of certain metals chromium, iron and zinc are moderately polluted compared to the results with the reference values of literature and others that are highly polluted by iron. However, due to a greater number of wells in production in those locations, those higher concentrations, it can be suggested a possible influence of oi production in some areas with concentrations of chromium and lead are higher than the rest of the points of monitoring. Moreover, it is observed that the highest levels of metals found in sediment of finer texture and more organic matter content

Influência da adição de gres porcelanato no comportamento mecânico e microestrutural em pastas de cimento portland para cimentação de poços de petróleo

Cementation operation consists in an extremely important work for the phases of perforation and completion of oil wells, causing a great impact on the well productivity. Several problems can occur with the cement during the primary cementation, as well as throughout the productive period. The corrective operations are frequent, but they are expensive and demands production time. Besides the direct cost, prejudices from the interruption of oil and gas production till the implementation of a corrective operation must be also taken into account. The purpose of this work is the development of an alternative cement paste constituted of Portland cement and porcelainized stoneware residue produced by ceramic industry in order to achieve characteristics as low permeability, high tenacity, and high mechanical resistance, capable of supporting various operations as production or oil wells recuperation. Four different concentration measures of hydrated paste were evaluated: a reference paste, and three additional ones with ceramic residue in concentrations of the order of 10%, 20% and 30% in relation to cement dough. High resistance and low permeability were found in high concentration of residues, as well as it was proved the pozolanic reactivity of the residue in relation to Portland cement, which was characterized through x-ray and thermogravimetry assays. It was evident the decrease of calcium hydroxide content, once it was substituted by formation of new hydrated products as it was added ceramic residue

Influência da areia argilosa na recuperação de petróleo por injeção de vapor

Continuous steam injection is one of heavy oil thermal recovery methods used in the Brazilian Northeast because of high occurrence of heavy oil reservoir. In this process, the oil into the reservoir is heated while reduces, substantially, its viscosity and improves the production. This work analyzed how the shaly sand layers influenced in the recovery. The studied models were synthetics, but the used reservoir data can be extrapolated to real situations of Potiguar Basin. The modeling was executed using the STARS - Steam Thermal and Advanced Process Reservoir Simulator - whose version was 2007.10. STARS is a tool of CMG Computer Modeling Group. The study was conducted in two stages, the first we analyzed the influence of reservoir parameters in the thermal process, so some of these were studied, including: horizontal permeability of the reservoir and the layer of shaly sand, ratio of horizontal permeability to vertical permeability, the influence of capillary pressure layer of shaly sand and as the location and dimensions of this heterogeneity can affect the productivity of oil. Among the parameters studied the horizontal permeability of the reservoir showed the most significant influence on the process followed by diversity. In the second stage three models were selected and studied some operational parameters such as injection rate, distance between wells, production time and completion intervals. Among the operating parameters studied the low rate and intermediate distances between wells showed the best recoveries

Metodologia de utilização de dados de sensoriamento remoto em zonas costeiras sob influência da indústria petrolífera

Oil spills in marine environments represent immediate environmental impacts of large magnitude. For that reason the Environmental Sensitivity to Oil Maps constitute a major instrument for planning actions of containment and cleanup. For both the Environmental Sensitivity Maps always need to be updated, to have an appropriate scale and to represent accurately the coastal areas. In this context, this thesis presents a methodology for collecting and processing remote sensing data for the purpose of updating the territorial basis of thematic maps of Environmental Sensitivity to Oil. To ensure greater applicability of the methodology, sensors with complementary characteristics, which provide their data at a low financial cost, were selected and tested. To test the methodology, an area located on the northern coast of the Northeast of Brazil was chosen. The results showed that the products of ASTER data and image hybrid sensor PALSAR + CCD and HRC + CCD, have a great potential to be used as a source of cartographic information on projects that seek to update the Environmental Sensitivity Maps of Oil

Influência da adição de cinza do bagaço de cana calcinada em sistemas de pastas para cimentação de poços petrolíferos

Cementing operation is one of the most important stages in the oil well drilling processes and has main function to form hydraulic seal between the various permeable zones traversed by the well. However, several problems may occur with the cement sheath, either during primary cementing or during the well production period. Cements low resistance can cause fissures in the cement sheath and compromise the mechanical integrity of the annular, resulting in contamination of groundwater and producing zones. Several researches show that biomass ash, in particular, those generated by the sugarcane industry have pozzolanic activity and can be added in the composition of the cementing slurries in diverse applications, providing improvements in mechanical properties, revenue and cement durability. Due to the importance of a low cost additive that increases the mechanical properties in a well cementing operations, this study aimed to potentiate the use of sugarcane bagasse ash as pozzolanic material, evaluate the mechanisms of action of this one on cement pastes properties and apply this material in systems slurries aimed to cementing a well with 800 m depth and geothermal gradient of 1.7 °F/100 ft, as much primary cementing operations as squeeze. To do this, the ash beneficiation methods were realized through the processes of grinding, sifting and reburning (calcination) and then characterization by X-ray fluorescence, XRD, TG / DTG, specific surface area, particle size distribution by laser diffraction and mass specific. Moreover, the ash pozzolanic activity added to the cement at concentrations of 0%, 20% and 40% BWOC was evaluated by pozzolanic activity index with lime and with Portland cement. The evaluation of the pozzolanic activity by XRD, TG / DTG and compressive strength confirmed the ash reactivity and indicated that the addition of 20% in the composition of cement slurries produces improvement 34% in the mechanical properties of the slurry cured. Cement slurries properties evaluated by rheological measurements, fluid loss, free fluid, slurry sedimentation, thickening time and sonic strength (UCA) were satisfactory and showed the viability of using the sugarcane ash in cement slurries composition for well cementing

Contribuição da Geodésia ao monitoramento costeiro do Litoral Setentrional do Rio Grande do Norte, área de influência da indústria petrolífera

The general objective of this thesis has been seasonal monitoring (quarterly time scale) of coastal and estuarine areas of a section of the Northern Coast of Rio Grande do Norte, Brazil, environmentally sensitive and with intense sediment erosion in the oil activities to underpin the implementation of projects for containment of erosion and mitigate the impacts of coastal dynamics. In order to achieve the general objective, the work was done systematically in three stages which consisted the specific objectives. The first stage was the implementation of geodetic reference infrastructure for carrying out the geodetic survey of the study area. This process included the implementation of RGLS (Northern Coast of the RN GPS Network), consisting of stations with geodetic coordinates and orthometric heights of precision; positioning of Benchmarks and evaluation of the gravimetric geoid available, for use in GPS altimetry of precision; and development of software for GPS altimetry of precision. The second stage was the development and improvement of methodologies for collection, processing, representation, integration and analysis of CoastLine (CL) and Digital Elevation Models (DEM) obtained by geodetic positioning techniques. As part of this stage have been made since, the choice of equipment and positioning methods to be used, depending on the required precision and structure implanted, and the definition of the LC indicator and of the geodesic references best suited, to coastal monitoring of precision. The third step was the seasonal geodesic monitoring of the study area. It was defined the execution times of the geodetic surveys by analyzing the pattern of sediment dynamics of the study area; the performing of surveys in order to calculate and locate areas and volumes of erosion and accretion (sandy and volumetric sedimentary balance) occurred on CL and on the beaches and islands surfaces throughout the year, and study of correlations between the measured variations (in area and volume) between each survey and the action of the coastal dynamic agents. The results allowed an integrated study of spatial and temporal interrelationships of the causes and consequences of intensive coastal processes operating in the area, especially to the measurement of variability of erosion, transport, balance and supply sedimentary over the annual cycle of construction and destruction of beaches. In the analysis of the results, it was possible to identify the causes and consequences of severe coastal erosion occurred on beaches exposed, to analyze the recovery of beaches and the accretion occurring in tidal inlets and estuaries. From the optics of seasonal variations in the CL, human interventions to erosion contention have been proposed with the aim of restoring the previous situation of the beaches in the process of erosion.

Monitoramento da morfologia costeira em setores da bacia potiguar sob influência da indústria petrolífera utilizando geodésia de alta precisão e laser escâner terrestre

The objective of this Doctoral Thesis was monitoring, in trimestral scale, the coastal morphology of the Northeastern coast sections of Rio Grande do Norte State, in Brazil, which is an area of Potiguar Basin influenced by the oil industry activities. The studied sections compose coastal areas with intense sedimentary erosion and high environmental sensitivity to the oil spill. In order to achieve the general objective of this study, the work has been systematized in four steps. The first one refers to the evaluation of the geomorphological data acquisition methodologies used on Digital Elevation Model (DEM) of sandy beaches. The data has been obtained from Soledade beach, located on the Northeastern coast of Rio Grande Norte. The second step has been centered on the increasing of the reference geodetic infrastructure to accomplish the geodetic survey of the studied area by implanting a station in Corta Cachorro Barrier Island and by conducting monitoring geodetic surveys to understand the beach system based on the Coastline (CL) and on DEM multitemporal analysis. The third phase has been related to the usage of the methodology developed by Santos; Amaro (2011) and Santos et al. (2012) for the surveying, processing, representation, integration and analysis of Coastlines from sandy coast, which have been obtained through geodetic techniques of positioning, morphological change analysis and sediment transport. The fourth stage represents the innovation of surveys in coastal environment by using the Terrestrial Laser Scanning (TLS), based on Light Detection and Ranging (LiDAR), to evaluate a highly eroded section on Soledade beach where the oil industry structures are located. The evaluation has been achieved through high-precision DEM and accuracy during the modeling of the coast morphology changes. The result analysis of the integrated study about the spatial and temporal interrelations of the intense coastal processes in areas of building cycles and destruction of beaches has allowed identifying the causes and consequences of the intense coastal erosion in exposed beach sections and in barrier islands

Influência de fatores ambientais na incidência do vírus da infecção hipodermal e necrose hematopoiética (IHHNV) no camarão Litopenaeus vannamei cultivado em fazendas do Estado do Rio Grande do Norte (RN)

The shrimp farming industry is the most profitable area of the aquaculture at Rio Grande do Norte (RN) state, which is one of the largest producers in Brazil. However the infections that affect the shrimp cause major economic losses. The infection is a result of the interaction between the shrimp, the environment and pathogen. The change of these factors may lead to a condition of stress and susceptibility to opportunistic infections. One of these infections caused by Infectious Hypodermal and Hematopoietic Necrosis Virus (IHHNV) is widely distributed in several countries and affects a wide range of hosts. To optimize conditions for production of Litopenaeus vannamei shrimp, the more species cultivated in Brazil, it is necessary to understand the effects of environmental factors in the susceptibility of this species to infections. The aim of this study was to determine the IHHNV prevalence and to investigate the influence of environmental factors as salinity, temperature, stocking density, dissolved oxygen and rainfall in the IHHNV incidence in L. vannamei grown in farms, in the RN state. To determine the IHHNV prevalence were used 1089 samples of L. vannamei collected in seven farms. To perform the study about the influence of environmental factors, 525 samples of L. vannamei shrimp were collected in eight farms located in regions of low (0-1 ), medium (21-30 ) and high (38-57 ) salinity, using extensive (≤15 shrimp/m2 ), semi-intensive (18-33 shrimp/m2) or intensive (>36 shrimp/m2) stocking density systems. The IHHNV infection was determined in pleopod and hemolymph using the polymerase chain reaction (PCR). The environmental factors were recorded during the collection of animals, using a refractometer to measure the salinity and a multi-parameter meter to measure the temperature and concentration of dissolved oxygen in the water. The IHHNV prevalence in RN was 43% (468 infected shrimp out of 1089), varying on different farms. On the seven farms studied, IHHNV prevalence ranged from 18.6% to 54.8%. The infection rates in the shrimp cultured in low, medium and high salinity were respectively 43.10% (125/290), 31.2% (15/48) and 24.6% (46/187) and was significantly higher in shrimp grown in low salinity (P<0.001). The infection rates in ponds of extensive, semi-intensive and intensive systems were respectively, 28.7%, 28.28% and 47.84%, and was significantly higher in high stocking densities (P<0.001). This study indicated a high IHHNV prevalence and a significant effect of salinity and stocking density, but not of the temperature, rainfall and dissolved oxygen on the IHHNV infection rate in the L. vannamei shrimp cultured in the northeastern Brazil

Influência de fatores biopsicossociais sobre a mortalidade de idosos no município de Santa Cruz/RN: um estudo prospectivo

The aging process if characterizes for a complex events network, from multidimensional nature, that encloses biological, social, psychic and functional aspects. The alteration of one or more aspects can speed up the aging process, anticipating limitations and until the death in the aged. For an adjusted confrontation of this question is necessary an interdisciplinary vision, in which the some areas of the knowledge can interact and with this to intervenes of the best possible form. Then, information derived from studies of aspects related to incidence, morbidity-mortality and transition patterns, involved in the health-illness process can more accurately identify risk groups thereby establishing links between social factors, illness, incapacity and death. Thus, this study aimed to identify, by a multidimensional vision, the risk factors of mortality in a coorth of elderly in a city in the interior of the state of Rio Grande do Norte (RN), Brazil. A prospective study carried out in Santa Cruz RN, where 310 elderly were randomly selected to form a baseline. The follow-up was 53 months. The predictive variables were divided into sociodemographic, physical health, neuropsychiatric and functional capacity. The statistical analysis carried out by bivariate analysis, survival analysis, followed by binary logistic regression and Cox regression, in the multivariate analysis, considering significant levels p < 0.05 and confidence interval (CI) of 95%. A total of 60 (19.3%) elderly died during the follow-up, where cardiovascular disease was the main cause. The survival was approximately 24.8 months. The study of general survival showed, at 12, 24, 36, and 48 months of observation, a survival rate of 97%, 54%, 31%, and 5% respectively, with a statistical difference in survival only observed for the variables of cognitive function and Basic Activities of Daily Living. In the logistic regression analysis, the risk factors identified were cognitive deficits (OR = 8.74), poor perception of health (OR = 3.89) and dependence for Basic Activities of Daily Living (OR = 3.96). In the Cox analysis, as well as dependence for Basic Activities of Daily Living (HR = 3.17), cognitive deficit (HR = 4.30) and stroke (CVA) (HR = 3.49) continued as independent risk factors for death. The risk factors found in the study can be interpreted as the primary predictors for death among elderly members of the community. Therefore, improvements in health conditions, with actions towards sustaining an autonomous life with special attention for elderly with cognitive impairment, could mean additional healthy quality of life, resulting in the reduction of premature mortality in this population

Hiperidrose compensatória após simpatectomia toracoscópica: características, incidência e influência na satisfação do paciente

Hyperhidrosis is an idiopathic condition characterized by excessive sweating. Symptoms generally begin in childhood or early adolescence, and rarely improve with age. The excessive localized sweating generally occurs either spontaneously, or in association with stressful or emotionally charged situations. This prospective study aimed to investigate predictive factors for compensatory hyperhidrosis after thoracoscopic sympathicotomy. From 2000 to 2002, 80 patients (53 female and 27 male) underwent hyperhidrosis surgery. The patients, ranging from 12 to 56 years old, were studied and followed-up for 42.51 ±5.98 months. A satisfaction grading using a visual analogue scale -VAS (0 = not at all satisfied, and 10 = fully satisfied) was used. The surgical procedure was performed bilaterally on the second ganglion (T2) for facial hyperhidrosis, on the third and fourth ganglia (T3 and T4) for axillary hyperhidrosis, and on the third ganglion (T3) for palmar hyperhidrosis. The results showed that, 68 patients (85%) presented with compensatory sweating (CS), which was classified as mild (33.8%), moderate (33.8%) and severe (32.4%). Considering the final surgical results, 70 patients (87.5%) were satisfied with the outcome of the operation, while 10 patients (12.5%) were dissatisfied. Degrees of satisfaction varied according to sex, age, BMI and extent of denervation. Moreover, the compensatory hyperhidrosis was more severe in abdomen and back than in legs. In conclusion, although CS is a frequent adverse effect of sympathicotomy, the degree of patient satisfaction was high. Some factors were related to the occurrence and severity of CS and the most adequate patients to be submitted to this operation are young adult women whose BMI is less than 24.9

Influência da dor na capacidade funcional de idosos institucionalizados

The aim of this study was to evaluate the pain influence regarding location, intensity and duration over functional capacity in institutionalized elderly (Fundacao Leur Brito). This is a descriptive exploratory study with a transversal design and quantitative approach. The population of the study was composed of 60 elderly, being 50% males with 60 years-old minimum age and 104 years-old maximum age, with mean age 77,6 (?}11,64) years-old. Data was collected by a structured query formulary divided in four parts: 1) Social, health and demographic characterization; 2) Pain related aspects (time and location); 3) Pain evaluation by numeric scale and 4) Functional capacity measured by Barthel Index. It was observed after evaluation by Squared-chi test (x2) statistical significant difference between pain presence and Barthel Index activities: bath (pvalue=0,015), dressing (p-value= 0,041), intimal hygiene transference (p-value=0,001), chair and bed transference (p-value=0,032), walking (p-value=0,010) and go upstairs (p-value=0,008). It was also observed statistical difference between total Barthel score (dependent/independent) and pain presence, p-value<0, 000. Through data obtained by this study, a multiprofessional approach is necessary to proper pain control and maintenance and/or regain of functional capacity, leading to an increase in life quality with more independence and autonomy to elderly

Síndrome metabólica e risco cardiovascular na pós- menopausa: avaliação por diferentes critérios diagnósticos e influência de fatores sócio-econômicos

The metabolic syndrome (MetS) involves a group of risk factors and is associated with a significantly higher risk of developing cardiovascular diseases (CVD) and type 2 diabetes. Recent studies have shown the importance of preventing CVD through early diagnosis and treatment of patients with MetS. The objective of our study was to determine the prevalence of MetS by different diagnostic criteria in postmenopausal women and analyze the influence of socioeconomic factors on cardiovascular risk in this sample of the population. A cross-sectional study involving 127 postmenopausal women (45 to 64 years) from Natal and Mossoró, Brazil. The study was approved by the Research Ethics Committee of the Federal University of Rio Grande do Norte. The experimental protocol consisted of applying structured interview, clinical examination and implementation of dosages blood. The diagnosis of MetS was based on NCEP-ATP III (National Cholesterol Education Program-Adult Treatment Panel III) and IDF (International Diabetes Federation) criteria. The research was accomplished with the participation of an interdisciplinary team in their several phases. The result of the sample studied had mean age of 53.9 ± 4.6 years and per capita income of 54.5 dollars. The prevalence of MetS, according to NCEP-ATP III and IDF criteria, was 52.8% and 61.4$, respectively. The agreement rate between NCEP-ATP III and IDF criteria was 81.9%, with a kappa value of 0.63 (CI 95%, 0.49-0.76), indicating good agreement between the two definitions. The most prevalent cardiovascular risk factor was HDL < 50 mg/dl, observed in 96.1% of the women analyzed, followed by increased waist circumference (≥ 80 cm) in 78.0%, elevated blood pressure in 51.2%, triglycerides ≥ 150 mg/dl in 40.9% and glycemia ≥ 100 mg/dl in 37.0% of the women. The occurrence of MetS was significantly associated with schooling and body mass index (BMI). High blood pressure was significantly associated with low family income, low schooling and weight gain. There was no significant association between the intensity of climacteric symptomatology and the occurrence of MetS. The conclusions of the research were that MetS and its individual components show a high prevalence in postmenopausal Brazilian women, and significant associations with weight gain and low socioeconomic indicators. The data point to the need for an interdisciplinary approach at the basic health care level, directed toward the early identification of risk factors and the promotion of cardiovascular health of climacteric women.

Influência do ácido α-lipóico na adaptação antioxidante ao exercício físico em ratas wistar hígidas e ovariectomizadas

Introdução: Os hormônios estrogênicos possuem importante papel na defesa contra as espécies reativas do oxigênio, fato que se evidencia na maior incidência de doenças cardiovasculares e neurodegenerativas após a menopausa. O exercício físico melhora as defesas antioxidantes, contudo em altas cargas e em baixas concentrações de estrógeno possui efeito aditivo ao dano oxidativo. O ácido α-lipóico possui uma ampla gama de ação antioxidante e poderia contribuir para diminuição do dano nestas condições. Objetivo: O objetivo deste estudo é caracterizar a ação do ácido α-lipóico sobre a adaptação antioxidante e funções reprodutivas de ratas submetidas a natação moderada. Material e métodos: Os animais foram submetidos a natação diária (1 hora) e sacrificados após 30, 60 e 90 dias. Os animais foram divididos em controles sedentários e exercitados; suplementados (ácido α-lipóico 100mg/Kg/dia) sedentários e exercitados e animais ovariectomizados e suplementados com ácido lipóico. Avaliou-se diariamente o ciclo estral e os seguintes marcadores de estresse oxidativos foram mensurados em fígado e sangue: atividade enzimática da SOD, GPx e CAT, além do SRAT e GSH. Resultados: O protocolo de exercício aumentou a duração do ciclo estral no grupo controle exercitado, sobretudo na fase diestral. Neste mesmo grupo, houve diminuição da lipoperoxidação com melhora da atividade antioxidante da SOD e GPx. O grupo exercitado e suplementado não apresentou alteração na duração do ciclo estral e manteve os benefícios sobre o sistema antioxidante antes observado nos animais exercitados. A suplementação antioxidante juntamente com a natação em períodos superiores a 30 dias, diminuiu o processo de adaptação antioxidante quando comparado aos animais somente exercitados. Nos animais ovariectomizados, o exercício e a suplementação com ácido lipóico não promoveu adaptação antioxidante ao contrário dos demais grupos. Conclusão: O aumento na duração do ciclo estral e a melhora nos marcadores de estresse oxidativo seriam uma resposta adaptativa frente ao exercício moderado. O ácido lipóico impediu a alteração no ciclo induzida pelo exercício, mas preservou a melhoria no sistema antioxidante. A depleção estrogênica provocada pela ovariectomia eleva o potencial de dano oxidativo gerado pelo exercício. A ação antioxidante do LA na presença de estrógeno diminuiu excessivamente o dano oxidativo, comprometendo a adaptação antioxidante a natação. Nos animais ovariectomizados, contudo, o AL promoveu adaptação antioxidante ao exercício

Influência da esplenectomia na biodistribuição do ácido dimercaptosuccínico-tecnécio-99m (99mTc-DMSA) em ratos Wistar

A esplenectomia é indicada em doenças hematológicas, hiperesplenismo grave, traumas e tem sido causa de importantes alterações metabólicas e imunológicas. O objetivo do presente trabalho é avaliar se a retirada do baço altera a biodistribuição do radiofármaco DMSA Tc99m em ratos Wistar e se há correlação com possíveis alterações da função renal. Foram usados dois grupos: esplenectomia (n=6) e controle (n=6) animais não operados. Após 15 dias, foi administrado 0,1 ml de DMSA-Tc99m via plexo orbital (0,66 MBq). Trinta minutos depois, foram retiradas amostras do rim, coração, pulmão, tireóide, estômago, bexiga, fêmur, sangue. Após pesadas as amostras, foi determinado o percentual de radioatividade/g (% ATI/g) em cada uma delas, com o Wizard Gama Counter Perkin-Elmer . Dosadas uréia e creatinina sérica, hematócrito, plaquetas e leucócitos. Estatística pelo teste t, com significância 0,05. Foi observada redução significante no %ATI/g no rim e sangue (p<0,05) dos animais esplenectomizados, aumento significante (p<0,05) da uréia (88,8±18,6mg/dL) e creatinina (0,56±0,08), comparado aos controles (51,5±1,6 e 0,37±0,02mg/dL, respectivamente) assim como leucocitose, aumento de plaquetas e redução de hematócrito. Em conclusão, a esplenectomia provocou comprometimento da função renal, repercutindo na alteração da captação de DMSA 99mTc pelo rim de ratos. Uma parceria entre a Unidade de Medicina Nuclear da Liga Norteriograndense Contra o Câncer e o Núcleo de Cirurgia Experimental da Universidade Federal do Rio Grande doNorte tornou possível a realização deste trabalho, que contou com a participação de profissionais de diferentes áreas como: Biologia, Biomedicina, Medicina Nuclear, Cirurgia Geral, Bioquímica e Estatística, atestando dessa forma o caráter multidisciplinar do trabalho