Teias de caridade e o lugar social dos expostos da Freguesia de Nª Srª da Apresentação: capitania do Rio Grande do Norte, século XVIII

The abandonment of newborn children is a reality nowadays. This reality enables us to discuss this issue in other temporalities, in all kinds of societies. Thus, this work aims to demonstrate how the population that lived at Freguesia de Nossa Senhora da Apresentação, a civil parish at a Rio Grande do Norte captaincy, socially placed the abandoned newborn during in the eighteenth century. These newborn were called exposed ones at the time and were inserted in a regional Exposed Circle. The research also discussed how the local Council assembly sheltered these newborn. For research development the following manuscript documents were used: baptism, wedding and demise documents at Freguesia de Nossa Senhora da Apresentação as well as the first Book of Records if the matrix church at this civil parish. The research also considered the terms of the Council assembly. Some printed documents were used such as Philippine Ordainments, the First Constitutions of the Archbishop in 1707 including the Lunario contents as well as texts from André João Antonil and Henry Koster. In the analysis reference work related to Social History was used. Thus, it is possible confirm that there was construction of socially accepted places for these exposed on behalf of the colonist at the region

Avaliação do risco ocupacional de trabalhadores expostos a agrotóxicos no município de Touros/Rio grande do Norte

The use of pesticides is being used intensively with severe consequences for exposed farmers. This study aimed to describe the socioeconomic and health profiles of 60 farmers in the city of Touros / RN through the questionnaire recommended by: (International Commission for Protection against Environmental Mutagens and Carcinogens (ICPEMC). The analysis of these data allowed to prove the importance of knowledge about the socioeconomic and health profile of rural farmers as a way to understand the reality of this population, that is vulnerable to exposure due to the lack of knowledge and conditions. Aiming to analyze the frequency of micronucleus (MN) and other nuclear abnormalities in oral mucosa cells of 54 farmers that work in the city of Touros / RN it was applied the micronucleus test (MN) in oral mucosa. Our results showed an increased frequency of MN and other nuclear abnormalities related to the exposure and effects of pesticides on health. Based on the results, it is clear that farmers are using pesticide in the wrong way and compromising their health. A Cordel has been developed as a method to taking the results to the people affected by the pesticides. Therefore this study alerts to the need for profound changes in the social, cultural and health context to reduce health risks for both people and for the environment

Efeito do parceiro social sobre a resposta comportamental ao ambiente novo em sagüi comum (Callithrix jacchus)

Algumas pesquisas demonstram que a presença de um parceiro social durante uma situação de risco modula a resposta ao estresse, atenuando seus efeitos negativos. Neste estudo, 8 díades de machos e 8 de fêmeas de sagüi comum (Callithrix jacchus) foram expostos a um ambiente novo, sozinhos e acompanhados de um parceiro de mesmo sexo e idade. Quando submetidos a um ambiente novo em companhia de um animal de mesmo sexo, os machos apresentaram um perfil mais filiativo enquanto as fêmeas foram mais competitivas entre si. Os resultados mostram que a resposta comportamental é sexualmente dimórfica, e que machos e fêmeas utilizam diferentes estratégias quando confrontados com situações desafiadoras no ambiente natural Abstract Some researches demonstrate that the presence of a social partner during a challenging situation modulates the stress response, decreasing its negative effects. In this study common marmoset (Callithrix jacchus) males and females were exposed to a new environment, alone or in companion of a social partner of the same sex and age. When submitted to new environment in companion of a same-sex social partner males showed more affiliation whereas females performed agonistic behaviors. The results show that behavioral response is sexually dimorphic and that males and females used different strategies when facing challenging situations in natural conditions

Avaliação da toxicidade de florações naturais e de cultura de cianobactérias: efeitos sobre Ceriodaphnia silvestri (Crustacea, Cladocera)

The incidence of toxic cyanobacterial blooms is one of the important consequences of eutrophication in aquatic ecosystems. It is a very common phenomenon in reservoirs and shrimp ponds in the State of Rio Grande do Norte (RN), Brazil. Cyanobacterias produce toxins which can affect aquatic organisms and men trough the food chain. Aiming to contribute to the studies of cyanobacterias in RN, we propose: a) to evaluate the toxicity of isolated cyanobacterias in important fresh-water environments; and b) to verify the effects of both natural and cultured blooms occurred in reservoirs for human supply and in the cladoceran Ceriodaphnia silvestrii. This study was carried out using samples of natural blooms occurred between March and October of 2004 in Gargalheiras Dam (08º L e 39º W), in July of 2004 in Armando Ribeiro Gonçalves Dam (06o S e 37o W) and in commercial shrimp ponds (Litopenaeus vannamei) located in fresh-water environments. The samples were collected with plankton net (20µm.) for identification, isolation and obtaining of phytoplanktonic biomass for liophilization and later toxicity bioassays. The toxicity of cultured samples and natural blooms was investigated through bioassays in Swiss mice. Quantification of cyanobacteria in samples was conducted following the Ütermol method, with 300mL samples fixed with lugol. The toxicity test with Ceriodaphnia silvestrii followed ABNT, 2001 recommendations, and were accomplished with natural hepatotoxic bloom s samples and cultured samples of both non-toxic and neurotoxic C. raciborskii. In this test, five newborns, aged between 6 and 24 hours, were exposed to different concentrations (0 a 800 mg.L-1) of crude cyanobacterial extracts during 24 and 48 hours. Three replicates were used per treatment. The pH, temperature and dissolved oxygen at the beginning and after 24 and 48hours from the test were measured. We estimated the CL50 through the Trimmed Spearman-Karber method. The blooms were constituted by Microcystis panniformis, M. aeruginosa, Anabaena circinalis, Cylindrospermopsis raciborskii and Planktothrix agardhii, producers of mycrocistin-LR confirmed with HPLC analysis. Samples of hepatotoxic blooms registered toxinogenic potential for C. silvestrii, with CL50-24h value of 47.48 mg.L-1 and CL5048h of 38.15 mg.L-1 for GARG samples in march/2005; CL50-24h of 113,13 mg.L-1 and CL5048h of 88,24 mg.L-1 for ARG July/2004; CL50-24h of 300.39 mg.L-1 and CL50-48h of 149.89 mg.L-1 for GARG October/2005. For cultured samples, values of CL50-24h and CL50-48h for C. raciborskii toxic strains were 228.05 and 120.28 mg.L-1, respectively. There was no mortality of C. silvestrii during the tests with non-toxic C. raciborskii strain. The toxicity test with C. silvestrii presented good sensitivity degree to cyanotoxins. The toxicity of natural hepatotoxic blooms samples (microcystins) and cultured neurotoxic saxitoxins producer samples analyzed in this study give us strong indications of that toxin s influence on the zooplanktonic community structure in tropical aquatic environments. Eleven cyanobacteria strains were isolated, representing 6 species: Anabaenopsis sp., Cylindrospermopsis raciborskii, Chroococcus sp., Microcystis panniformis, Geitlerinema unigranulatum e Planktothrix agardhii. None presented toxicity in Swiss mice. The strains were catalogued and deposited in the Laboratório de Ecologia e Toxicologia de Organismos Aquáticos (LETMA), in UFRN, and will be utilized in ecotoxicológical and ecophysiological studies, aiming to clarify the causes and control of cyanobacterial blooms in aquatic environments in RN. This state s reservoirs must receive broader attention from the authorities, considering the constant blooms occurring in waters used for human consumption

Determinantes genéticos da hanseníase em uma população do Rio Grande do Norte

Background: Leprosy can cause severe disability and disfigurement and is still a major health in different parts of the world. Only a subset of those individuals exposed to the pathogen will go on to develop clinical disease and there is a broad clinical spectrum amongst leprosy patients. The outcome of infection is in part due to host genes that influence control of the initial infection and the host´s immune response to that infection. Aim: Evaluate if polymorphisms type SNP in the 17q118q21 chromosomic region contribute to development of leprosy in Rio Grande do Norte population. Material and methods: A sample composed of 215 leprosy patients and 229 controls drawn from the same population were genotyped by using a Snapshot assay for eight genes (NOS2A, CCL18, CRLF3, CCL23, TNFAIP1, STAT5B, CCR7 and CSF3) located in chromosomic region 17q118q21. The genotype and allele frequency were measured and statistical analysis was performed by chi-square in SPSS version 15 and graph prism pad version 4 software. Results: Ours results indicated that the markers NOS2A8277, NOS2A8rs16949, CCR78rs11574663 and CSF38rs2227322 presented strong association with leprosy and their risk genotype were GG, TT, AA and GG respectively. The risk genotypes for all markers associated to leprosy presented recessive inheritance standard. When we compared the interaction among the markers in different combination we find that the marker NOS2A8277 associated with CCR78rs11574663 presented highest risk probability to development of leprosy. When we evaluated the haplotype of the risk markers it was found a haplotype associated with increase of the protection (CSF38rs22273228CC, CCR78 rs115746638GA, NOS2A8rs169498CT and NOS2A82778GA). The association of the clinical forms paucibacilary and multibacilary with markers showed that to the markers NOS2A8 2778GG, CCR78rs115746638AA and CSF38rs22273228GG there were a strong influence to migration to multibacilary pole and to marker NOS2A8rs169498TT the high proportion was found to the paucibacilary form. Conclusions: Changes in the genes NOS2A, CCR7 and CSF3 can influence the immune response against Mycobacterium leprae. The combination among these polymorphisms alters the risk probability to develop leprosy. The markers type SNP associated to development of the leprosy also are linked to clinical forms and its severity being the polymorphism NOS2A8rs169498TT associated with paucibacilar form and the polymorphisms NOS2A82778GG, CCR78rs115746638AA and CSF38rs22273228GG associated to multibacilar form

Investigação do papel modulador do Haloperidol sobre os níveis de proteínas relacionadas à plasticidade e preferência por objetos novos em camudongos

Dopamine (DA) is known to regulate both sleep and memory formations, while sleep plays a critical role in the consolidation of different types of memories. We believe that pharmacological manipulation of dopaminergic pathways might disrupt the sleep-wake cycle, leading to mnemonic deficits, which can be observed in both behavioral and molecular levels. Therefore, here we investigated how systemic injections of haloperidol (0.3 mg/kg), immediately after training in dark and light periods, affects learning assessed in the novel object preference test (NOPT) in mice. We also investigated the hippocampal levels of the plasticity-related proteins Zif-268, brain-derived neurotrophic factor (BDNF) and phosphorylated Ca2+/calmodulin-dependent protein kinases II (CaMKII-P) in non-exposed (naïve), vehicle-injected controls and haloperidol-treated mice at 3, 6 and 12 hours after training in the light period. Haloperidol administration during the light period led to a subsequent impairment in the NOPT. In contrast, preference was not observed during the dark period neither in mice injected with haloperidol, nor in vehicle-injected animals. A partial increase of CaMKII-P in the hippocampal field CA3 of vehicle-injected mice was detected at 3h. Haloperidol-treated mice showed a significant decrease in the dentate gyrus of CaMKII-P levels at 3, 6 and 12h; of Zif-268 levels at 6h, and of BDNF levels at 12h after training. Since the mnemonic effects of haloperidol were only observed in the light period when animals tend to sleep, we suggest that these effects are related to REM sleep disruption after haloperidol injection

Análise e avaliação dos elementos de penetração no solo de equipamentos rodoviários após revestimento

The main objective is to analyze the abrasive wear resistance to the low stress of the elements that make up the organs of road machinery that are exposed directly to contact with abrasives. These samples were analyzed after these elements are coated superficially by the process of welding electrode coated with (SAER) and the manual process of coating type LVOF thermal spraying. As well, is to provide suggestions for a better recovery and return of these elements, which are reducing costs and avoiding downtime in the fronts of service. The samples were made from a substrate of carbon ABNT 1045 tempered steel, following the same specifications and composition of metals and alloys of constituents was followed the standard governing the dimensions of these samples and in accordance with the corresponding size. The results were evaluated by testing the hardness, abrasion resistance to wear by the low stress and the loss of volume involving the microstructure of coatings analyzed

Avaliação de concretos reforçados por confinamento com manta de fibra de vidro estrutural e pré-impreganada

Due to the occurrence of diseases in the use of structural reinforcements in composites, with presentation of concrete blanket detachment, has been identified the need to evaluate the performance of concrete reinforced with glass fiber. This study aims to evaluate these concretes by means of testing methodologies, using concrete with low resistance with structural reinforcement for confinement by preimpregnated glass fiber and traditional fiberglass blanket. The first stage of work was the development of methodologies for analysis, opting for four types, such as the acoustic survey, strength to compressive, the pull-off and ultrasound. Next, tests were carried out using the four selected methodologies in 30 of proof-of-specimens by 5x10 cm, 15 were reinforced with the traditional fiberglass blanket with 5specimens exposed to test a marine environment of marine coastline of Natal-RN and 15 were reinforced with a pre-impregnated glass fiber blanket, as well as 5specimens exposed to a test environment of the marine coastline of Natal-RN. After conducting the acoustic survey, it has been verified a lack of delaminating and air bubbles in the samples, confirming the absence of gross shortcomings in the implementation of the ribs both the traditional fiberglass blanket and in the preimpregnated fiber glass blanket. After carrying out methods of pull-off and compressive strengthening test it was observed that the reinforced proof-bodies with pre-impregnated glass blanket showed maximum stresses higher than the traditional fiberglass blanket; consequently a greater grip with the formation of a smaller area of . fracture, unlike traditional glass mat, which showed lower maximum stresses, with a greater area of fracture. It was also found that the traditional fiberglass blanket presented detachment of blanket-concrete interface, unlike the pre-impregnated fiberglass blanket, which showed a better grip on the blanket-concrete interface. In the trial of ultrasound there was no presence of cracks in the blanket-concrete interface, yielding to both blankets good compactness of the concrete. At the end of this work, they were developed and proposed two methods of testing for evaluation of reinforced concrete structures with composites, for standardization, the acoustic survey and pull-off

Desenvolvimento de argamassa para restauração utilizando resíduo do polimento do porcelanato

The coatings mortars are essential elements of building structures because they execute an important role in protecting walls and are particularly exposed to aggressive action responsible for its degradation over time. The importance of wall coverings has been the subject of discussion and analysis in the conservation and rehabilitation of old buildings. Are sometimes removed and replaced with inappropriate solutions of constructive point of view or architecture. The most commonly used coatings on walls of old buildings is based on traditional hydraulic lime mortars. The present study aims at the formulation of new lime- based mortars and aerial fine aggregate, in order to contribute to a better field of conservation and restoration mortar coating of old buildings. Residue was used for polishing porcelain as fine aggregate, replacing the aggregate (sand), in percentages 05-30% by mass. We conducted a thorough evaluation of the mortar properties in fresh and hardened state by comparing the performance of the same with a reference mortar. The residue used was characterized as the density, bulk density, and particle size laser, scanning electron microscopy, X-ray diffraction and X-ray fluorescence. Formulations were produced 7, 6 with residue and one commonly used formulation, which served as a reference. In the formulations of lime mortars air (hydrated lime powder CH-I) has been adopted a stroke volume (1:3) with constant binder, was varied and the water / binder and aggregate and waste. For evaluation of mortars fresh, proceeded to consistency analysis, specific gravity, water retention and air content embedded. In the hardened state assays were performed in specific gravity, water retention, modulus of elasticity, tensile strength in bending, compressive strength, water absorption by capillary action, adhesion, tensile strength, resistance to shrinkage and salts by of crystallization trials with resources chloride solution, nitrate and sulfate all sodium in prismatic at 90 days of age, in addition to the micro structural analysis of mortars. Based on the results we can see that the mortar formulated with 10% content of waste and the reference free retraction feature more stable closer to neutrality. The composition of 10% was obtained better performance against the action of the salt crystallization. The mortar with 15% residue obtained better density, lower air content embedded and high capacity for water retention developing good workability. The replacement of 20% of waste generates a satisfactory utilization of resistance to compression, flexion and traction grip the base. And, finally, it can be seen that the mortar with 10, 15 and 20% residual show, in principle, good suitability as coatings, thus enabling a final result consistent with durability, workability and aesthetics developing therefore a material with better performance to repair or replace existing mortars in old buildings

Avaliação do efeito da adição de resíduo de borracha de pneu e brita calcária na formulação de compósitos cimentíceos

Researches have shown that the introduction of rubber in concrete improves the features of its deformability, as well as contributes to environmental disposal of waste generated in the tire retreading process. Furthermore, there is a high availability of limestone within RN and CE country. Ignorance about this stone, does not allow its wide use as aggregate, leaving, this abundant supply idle. A composite of limestone gravel, with proportions of tire rubber waste which could be used as concrete would be an alternative to concrete for low applications. Therefore, this research aims to evaluate the characteristics of concrete containing limestone gravel and proportions of little aggregate replacement (sand) by tire rubber waste. To this goal, the material components of the concrete were characterized, concrete specimens with limestone gravel were made, from the dash 1.0: 2.5: 3.5, varying the water/cement ratio, and inserting a commercial plasticizer, without a proportion of residue, known as reference. From this, concrete with and without the presence of the additive in the same proportions were chosen, as well as these with the use of granite gravel, for being the most used. Selected the references, to these, replacements of little aggregate (sand) were added replaced by rubber waste from the tire retreading process, treated with 1M NaOH in proportions from 5.0 to 20.0 % by mass, cured and exposed to the semiarid environment. The results indicate the possibility of using limestone gravel in the concrete composition with workability correction using plasticizer. There was a decrease in the mechanical properties of the concrete with increments of waste rubber, but there is an improvement in toughness and deformability of the composite, which makes it interesting for the construction of non-structural concrete floors, as well as, the rubber waste delayed the hardening process, continuing to gain resistance after 28 days

Protótipo de um microgerador termoelétrico de estado sólido: cogeração a gás

The thermoelectric energy conversion can be performed directly on generators without moving parts, using the principle of SEEBECK effect, obtained in junctions of drivers' thermocouples and most recently in semiconductor junctions type p-n which have increased efficiency of conversion. When termogenerators are exposed to the temperature difference (thermal gradient) eletromotriz a force is generated inducing the appearance of an electric current in the circuit. Thus, it is possible to convert the heat of combustion of a gas through a burner in power, being a thermoelectric generator. The development of infrared burners, using porous ceramic plate, is possible to improve the efficiency of heating, and reduce harmful emissions such as CO, CO2, NOx, etc.. In recent years the meliorate of thermoelectric modules semiconductor (TEG's) has stimulated the development of devices generating and recovery of thermal irreversibility of thermal machines and processes, improving energy efficiency and exergy these systems, especially processes that enable the cogeneration of energy. This work is based on the construction and evaluation of a prototype in a pilot scale, for energy generation to specific applications. The unit uses a fuel gas (LPG) as a primary energy source. The prototype consists of a porous plate burner infrared, an adapter to the module generator, a set of semiconductor modules purchased from Hi-Z Inc. and a heat exchanger to be used as cold source. The prototype was mounted on a test bench, using a system of acquisition of temperature, a system of application of load and instrumentation to assess its functioning and performance. The prototype had an efficiency of chemical conversion of 0.31% for electrical and heat recovery for cogeneration of about 33.2%, resulting in an overall efficiency of 33.51%. The efficiency of energy exergy next shows that the use of primary energy to useful fuel was satisfactory, although the proposed mechanism has also has a low performance due to underuse of the area heated by the small number of modules, as well as a thermal gradient below the ideal informed by the manufacturer, and other factors. The test methodology adopted proved to be suitable for evaluating the prototype

Efeitos do alcalóide indólico caulerpina, obtido de alga do gênero caulerpa, em modelo de colite experimental murina

As doenças inflamatórias intestinais são enfermidades onde a tolerância e homeostase da resposta inflamatória estão comprometidas, gerando lesões teciduais e favorecendo o surgimento de neoplasias. Há dois importantes exemplos de doenças inflamatórias intestinais, a colite ulcerativa, foco do modelo desse estudo, e a doença de Crohn. Os medicamentos utilizados no tratamento dessas doenças desencadeiam diversos efeitos adversos; além disso, em alguns pacientes, eles não são eficazes. Os extratos de algas têm demonstrado várias atividades biológicas, entre elas a atividade anti-inflamatória. Os extratos das algas do gênero Caulerpa foram utilizados em vários estudos, onde modelos inflamatórios foram analisados, entre eles o modelo de colite ulcerativa. A utilização do extrato metanólico da C. mexicana como terapêutica nesse modelo atenuou o quadro clinico desenvolvido pelos animais. Sendo assim, o presente estudo teve como objetivo analisar a ação terapêutica da Caulerpina (CLP), extraída da C. racemosa, no modelo murino de colite ulcerativa. Camundongos C57BL/6 machos foram expostos a uma solução de Dextrana Sulfato de Sódio (DSS) a 3% por sete dias. A partir do primeiro dia de exposição ao DSS os animais foram tratados em dias alternados com a CLP nas doses de 4 e 40 mg/kg e com a dexametasona (3 mg/kg) por via oral. O desenvolvimento da doença foi analisado através do índice de atividade da doença (IAD), que leva em consideração a perda de peso corporal, a consistência e a presença de sangue nas fezes. Após a eutanásia, o cólon foi removido e mensurado, e amostras do tecido colônico foram destinadas a análise histológica e à cultura para dosagem de citocinas. Os níveis de citocinas no sobrenadante da cultura do cólon foram mensurados por ELISA. O tratamento com a CLP (4 mg/kg) desencadeou significativa melhora quanto à perda de peso corporal e ao IAD, e atenuou o encurtamento do cólon em resposta ao DSS. Tal dose foi capaz de reduzir os níveis de citocinas pró-inflamatórias analisadas (TNF-, IFN-, IL-6, IL-17), mas não teve efeito significativo nas citocinas anti-inflamatórias IL-10 e TGF-. O tratamento com a CLP (40 mg/kg) não foi eficaz quanto a perda de peso e ao IAD, além de não ter atenuado a redução do cólon em resposta ao DSS. Essa dose conseguiu reduzir os níveis das citocinas pró-inflamatórias, porém não os níveis de IL-6. O tratamento com a dexametasona obteve melhora discreta quanto à perda de peso corporal e ao IAD, porém não atenuou a redução do cólon em resposta ao DSS. Esse tratamento também conseguiu reduzir todas as citocinas pró-inflamatórias testadas. Deste modo a CLP (4 mg/kg) demonstrou ser uma alternativa promissora no tratamento da colite ulcerativa, em razão dos seus efeitos benéficos sobre parâmetros clínicos, morfológicos e moleculares do modelo em estudo

Níveis de homocisteína e desempenho cognitivo em uma amostra populacional de idosos da cidade do Natal-RN

The imprecision of the frontier that separates those cognitive deficits inherent to the human physiological aging process from those which represent the early signs of nervous system degenerative pathologies ,very prevalent among the elderly, has brought attention to the need of studies aiming to establish clinical and/or laboratorial criteria to allow this differentiation. Elderly people living in poor and developing countries are frequently exposed to precarious socioeconomic conditions which facilitate the development of an array of pathologies which have metabolic and nutritional dysfunctions as the established or proposed etiological agents. The levels of certain micronutrients, such as the vitamins B12 and B9 (folic acid), and of some intermediary metabolites, such as homocysteine are being thought of as etiological factors and/or as biological markers of a group of alterations which affect the normal functioning of the nervous system with important reflexes upon cognitive performance. This study aims to investigate the influence of homocysteine, B12 vitamin and folic acid levels on the cognitive performance of the low income elderly population. This transversal study took place in Natal, Rio Grande do Norte State, Brazil, and involved 205 dwelling elderly people, users of the Programa de Saúde da Família, a public healthcare program, maintained by the city s health authorities. A multidimensional questionnaire was used to assess the socio-demographic aspects and the overall health and nutrition conditions. The cognitive performance was measured by the use of the Portuguese version of the Mini Mental State Exam (MMSE). The serum levels of homocysteine, B12 vitamin and folic acid were determined by chemiluminescence. The association between the socio-demographic and serum levels of Hcy, B12 vitamin and folic acid was determined by multiple linear regression. Serum levels higher than 13.5 μmol/l, indicative of hyperhomocysteinemia (HHcy), were found on 25.4% of the sample, being more prevalent in men (p<0.05). Deficitary levels of folic acid (<5ng/mol) and of B12 vitamin (<193 pg/ml) were found on 3.9% and 10.2% of the sample respectively. A negative correlation was found between cognitive performance with both age and HHcy and a positive correlation was found between cognitive performance and schooling. The isolated HHcy R2 values were an explanation to only 4% of the variance of the MMSE scores. However, when associated with schooling and age, this model explains about 25% of this association

IL-10 na patogênese da infecção por Leishmania infantum

Conselho Nacional de Desenvolvimento Científico e Tecnológico

Conhecimentos, atitudes e práticas sobre contracepção para adolescentes

Conhecer o fenômeno da gravidez no contexto da adolescência, considerando a importância da contracepção como valioso recurso deprevenção, é uma abordagem que carece de atenção e norteia esta pesquisa, cujoobjetivo é avaliar a vivência sexual dos adolescentes e uso de métodos contraceptivos a partir do que eles conhecem sobre esses métodos e de suas atitudes frente à contracepção. Trata-se de um estudo exploratório, conduzido com estudantesdo 7º ao 9º ano de escolaridade. Os instrumentos de coleta de dados foram construídos e validados com análise das melhores condições para obtenção derespostas coerentes. As variáveis consideradas para análise foram: comunicação, atitudes, conhecimentos sobre contracepção, sexo, idade e comportamento sexual. As análises foram realizadas através dos cálculos de frequência, testes de qui-quadrado, t de student e regressão logística (considerou-se p<0,05). Os instrumentos foram validados com alfa de Cronbach de 0,70. Houve dificuldades para aobtenção de dados confiáveis nos auto-relatos dos sujeitos, verificando-se a necessidade de investigar a coerência das repostas mesmo utilizando instrumentos já validados. Dos 570 participantes, 68,8% tinha até 14 anos. Apresentaram pouco conhecimento e atitudes desfavoráveis ou ambivalentes à contracepção. Apenas 65% conversaram sobre o tema e 21,4% declararam iniciação sexual. Entre esses, a maioria (60,8%) tinha até 15 anos e 49,3% nunca usaram qualquer método contraceptivo. Não houve diferença significativa no uso da prevenção entre os que conversaram ou não sobre contracepção (p= 0,201). Os resultados apontam adolescentes expostos não só à gravidez, como à DST e alerta para a necessidade deintervenções que viabilizem uma orientação sexual capaz de promover competências para práticas sexuais mais seguras. Além disso, este estudo alerta para a dificuldade em obter dados confiáveis em pesquisas com adolescentes e evidencia a importância em se verificar a coerência das respostas mesmo utilizando instrumentos validados