36 resultados para erros de resposta
Determinantes envolvidos na resposta imune celular humana à infecção por Leishmania infantum chagasi
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Visceral leishmaniasis (VL) is a disease caused by protozoa of the Leishmania donovani complex, whose infection has clinical spectrum ranging from asymptomatic infection to active disease characterized by fever, cachexia, hepatosplenomegaly, and immunosuppression. The healing or protective immunity require an antigen-specific type 1. The Montenegro skin test (DTH) has been interpreted as a marker of protective immunity. However, there is no known correlation between the DTH response to type 1 and DTH and immunity of type 1 are maintained in the long term. Thus, a longitudinal study of 8 years, nested in a cohort family held in Brazil, documented the status of DTH and cytokine production by peripheral blood mononuclear cells in response to antigen-specific stimulation. This study was the interdisciplinary approach of physicians, biochemists, nutritionists, veterinary medicine, biology and statistics. The results show that 46.2% of subjects were analyzed DTH positive at baseline. The prevalence of positive and DTH induration size increased with age (p = 0.0021). 15.7% of individuals positive DTH "retro-converted" the negative and 50.4% (64) of individuals negative DTH became positive. The size of DTH induration was correlated significantly with the antigen-induced production of IFN-γ (r = 0.6186, p = 0.0001). IL-6 was secreted at higher levels in peripheral blood mononuclear cells of individuals who "retro-converted" DTH positive to negative than individuals who remained stable DTH status (p = 0.005). Thus, IFN-γ produced by peripheral blood mononuclear cells, may be a surrogate marker for protective immunity instead of the DTH response. In addition, differences in innate immune response may determine whether individuals maintain or eliminate the infection by Leishmania infantum chagasi in asymptomatic patients
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This laboratory study involves the participation of a group with professionals from different areas that had contributed to the construction of a multidisciplinary knowledge, about biological response of titanium surfaces modified through thermochemical treatment by plasma. Thus, the crystalline phase was previously characterized in relation to the topography, roughness, molhability and nitrogen concentration in the samples surface. It s indispensable that materials implanted can influence in a good cellular response as well as promotes a bacteria action. Surfaces modified by plasma were exposed to different cultures such as: cellular (human osteoblastic) and bacteria (Staphylococcus epidermidis ATCC35984 and Pseudomonas aeruginosa ATCC 27853) in order to evaluate the biological response. It was evaluated the adhesion, proliferation, morphology and cellular preference of human ostheoblastic cells (HOST), as well as the formation of a biofilm and bacteria proliferation. It was still analyzed the bacteria selectivity ability in relation to the surfaces. The software Image Pro Plus was used to the counting of cells and bacteria adhered to the surface of disks. The results were submitted to the variance analysis (ANOVA), and then, by the Kruskal-Wallis test, using GraphPad Instat ® software, version 3.5 to Windows. The nitrided samples in spite of show a higher roughness and molhability showed a smaller bacteria growing and higher cellular proliferation, when compared to non treated samples, indicating that the treated material present a high efficiency to biomedical implants
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
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The food chain theory predict that presence of omnivory prevent the trophic cascade and could be a strong stabilizing factor over resource and consumer community dynamics, and that the nutrient enrichment destabilize populations dynamics. Most of the freshwater tropical reservoirs are eutrophic, and strategies that seek improve the water quality through the control of phytoplankton biomass and nutrient input, become essential for the improvement and preservation of water quality. The aim of this study was test the zooplanktivory (when larvae) and omnivory (when young and adult) effects of Nile Tilapia over the structure and dynamics of plankton communities, in addition or absence of nutrients enrichment. For this, one field experiment was performed with a factorial design 2x3 resulting in six treatments: control, without fish and nutrient (C); with omnivorous fish (O); with zooplanktivorous fish (Z); without fish and with enrichment of nutrients (NP); with omnivorous fish and nutrients (ONP); and, with zooplanktivorous fish and nutrients (ZNP). The two planktivory types reduced the zooplankton biomass and increased the phytoplankton biomass, but the omnivory of filter-feeding fish attenuated the trophic cascade magnitude. The fertilization by nutrients increases the nutrient concentrations in water and the phytoplankton biomass, but the effect on zooplankton is dependent of the trophic structure. In a general way, the effects of the fish and nutrient addition were addictive, but significant interactions among those factors were observed in the answer of some zooplankton groups. The effects of omnivorous fish over the temporal variability of phytoplankton and zooplankton biomass were very variable, the increase or reduce in variability of the plankton depending of the level of nutrients and of the analyzed variable. With base in this study, we conclude that the planktivory type exercised by the fish and the concentrations of nutrients in the water affects the force of pelagic trophic cascades and probably the success of biomanipulation programs for the handling of water quality in lakes and tropical reservoirs
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The attention with safety of the patients is important in the quality of the nursing and health care. In the pre-hospital care, such care is essential on site with the purpose of avoiding possible consequences to the individual, ensuring a fast and appropriate care, with improvement of the morbidity and reduction of the mortality. This medical attention is equally associated with the significant risks of adverse events and serious mistakes, which can be reduced with the awareness of the professionals, organization and quality management. It is a descriptive, transversal research, of quantitative approach, with the objective of identifying the risks for the safety of the patient during the mobile pre-hospital care under the view of the nurses, in a city of the Brazilian Northeast. The sample was formed by 23 nurses. The inclusion criteria: to have at least two years of experience and accept to participate on the research. The data collection was done in two steps, first photo collection, through the adapted method of photographic analysis, and the second with the application of questionnaire, divide in two parts: socio-professional data and digital photo punctuation instrument of the patient s safety. The majority of the nurses had an average working time in the mobile pre-hospital care of six years and six months, in the age group of 38 to 53 years old (69,56%) and with Lato sensu specialization (73,91%), being (29,41%) emergency and (29,41%) in intensive care. The (74%) have the Advance Cardiac Life Support (ACLS) and (100%) have the Pre-Hospital Trauma Life Support (PHTLS); (91, 30%) know the thematic safety of the patient. On the pictures it was observed a bigger variability of the categories (risks) where 44% of variance emerged on the first picture of the research. The pictures 4 and 9 with the average below 5 were classified as very insecure, while pictures 7 and 3 with an average above 7, very secure. On the results of risks observed for the patient s safety in the mobile pre-hospital care five categories emerged: organization and packaging of the equipment and materials, routines and specificities in the mobile pre-hospital care, risks on the management of medications, for traumas and infections. Starting from the analysis of these risks, it was proposed ten steps for the safety in the mobile pre-hospital care: 1- Identify the patient; 2- Safety related to prevention of infection; 3- Safety in the management of medications; 4- Safety and standardization of the packaging of equipment and materials; 5- Attention to the specificities of the mobile pre-hospital care; 6- Incentive and value the participation of the patient and family; 7- Promote the communication with the central of regulation; 8- Prevention of traumas and falls; 9- Protect the skin from additional injuries; 10- Understand the benefit of all the equipment in the ambulance. The multiple risks and their emerged combinations on the research indicate a variety of actions to be developed and stimulated, like the use of steps for the patient s safety in the mobile pre-hospital care which contributes with the aid and management of risks, reduction of mistakes, disabilities and death
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This work aims to show how the application of frequency selective surfaces (FSS) in planar antenna arrays become an alternative to obtain desired radiation characteristics from changes in radiation parameters of the arrays, such as bandwidth, gain and directivity. In addition to analyzing these parameters is also made a study of the mutual coupling between the elements of the array. To accomplish this study, were designed a microstrip antenna array with two patch elements, fed by a network feed. Another change made in the array was the use of the truncated ground plane, with the objective of increasing the bandwidth and miniaturize the elements of the array. In order to study the behavior of frequency selective surfaces applied in antenna arrays, three different layouts were proposed. The first layout uses the FSS as a superstrate (above the array). The second layout uses the FSS as reflector element (below the array). The third layout is placed between two FSS. Numerical and experimental results for each of the proposed configurations are presented in order to validate the research
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Composites based on PEEK + PTFE + CARBON FIBER + Graphite (G_CFRP) has increased application in the top industries, as Aerospace, Aeronautical, Petroleum, Biomedical, Mechanical and Electronics Engineering challenges. A commercially available G_CFRP was warmed up to three different levels of thermal energy to identify the main damage mechanisms and some evidences for their intrinsic transitions. An experimental test rig for systematize a heat flux was developed in this dissertation, based on the Joule Effect. It was built using an isothermal container, an internal heat source and a real-time measurement system for test a sample by time. A standard conical-cylindrical tip was inserted into a soldering iron, commercially available and identified by three different levels of nominal electrical power, 40W (manufacturer A), 40W (manufacturer B), 100W and 150W, selected after screening tests: these power levels for the heat source, after one hour of heating and one hour of cooling in situ, carried out three different zones of degradation in the composite surface. The bench was instrumented with twelve thermocouples, a wattmeter and a video camera. The twelve specimens tested suffered different degradation mechanisms, analyzed by DSC (Differential Scanning Calorimetry) and TG (Thermogravimetry) techniques, Scanning Electron Microscopy (SEM) and Energy-Dispersive X-Rays (EDX) Analysis. Before and after each testing, it was measured the hardness of the sample by HRM (Hardness Rockwell M). Excellent correlations (R2=1) were obtained in the plots of the evaporated area after one hour of heating and one hour of cooling in situ versus (1) the respective power of heat source and (2) the central temperature of the sample. However, as resulting of the differential degradation of G_CFRP and their anisotropy, confirmed by their variable thermal properties, viscoelastic and plastic properties, there were both linear and non-linear behaviour between the temperature field and Rockwell M hardness measured in the radial and circumferential directions of the samples. Some morphological features of the damaged zones are presented and discussed, as, for example, the crazing and skeletonization mechanism of G_CFRP
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The aim of the present study was to extract vegetable oil from brown linseed (Linum usitatissimum L.), determine fatty acid levels, the antioxidant capacity of the extracted oil and perform a rapid economic assessment of the SFE process in the manufacture of oil. The experiments were conducted in a test bench extractor capable of operating with carbon dioxide and co-solvents, obeying 23 factorial planning with central point in triplicate, and having process yield as response variable and pressure, temperature and percentage of cosolvent as independent variables. The yield (mass of extracted oil/mass of raw material used) ranged from 2.2% to 28.8%, with the best results obtained at 250 bar and 50ºC, using 5% (v/v) ethanol co-solvent. The influence of the variables on extraction kinetics and on the composition of the linseed oil obtained was investigated. The extraction kinetic curves obtained were based on different mathematical models available in the literature. The Martínez et al. (2003) model and the Simple Single Plate (SSP) model discussed by Gaspar et al. (2003) represented the experimental data with the lowest mean square errors (MSE). A manufacturing cost of US$17.85/kgoil was estimated for the production of linseed oil using TECANALYSIS software and the Rosa and Meireles method (2005). To establish comparisons with SFE, conventional extraction tests were conducted with a Soxhlet device using petroleum ether. These tests obtained mean yields of 35.2% for an extraction time of 5h. All the oil samples were sterilized and characterized in terms of their composition in fatty acids (FA) using gas chromatography. The main fatty acids detected were: palmitic (C16:0), stearic (C18:0), oleic (C18:1), linoleic (C18:2n-6) and α-linolenic (C18:3n-3). The FA contents obtained with Soxhlet dif ered from those obtained with SFE, with higher percentages of saturated and monounsaturated FA with the Soxhlet technique using petroleum ether. With respect to α-linolenic content (main component of linseed oil) in the samples, SFE performed better than Soxhlet extraction, obtaining percentages between 51.18% and 52.71%, whereas with Soxhlet extraction it was 47.84%. The antioxidant activity of the oil was assessed in the β-carotene/linoleic acid system. The percentages of inhibition of the oxidative process reached 22.11% for the SFE oil, but only 6.09% for commercial oil (cold pressing), suggesting that the SFE technique better preserves the phenolic compounds present in the seed, which are likely responsible for the antioxidant nature of the oil. In vitro tests with the sample displaying the best antioxidant response were conducted in rat liver homogenate to investigate the inhibition of spontaneous lipid peroxidation or autooxidation of biological tissue. Linseed oil proved to be more efficient than fish oil (used as standard) in decreasing lipid peroxidation in the liver tissue of Wistar rats, yielding similar results to those obtained with the use of BHT (synthetic antioxidant). Inhibitory capacity may be explained by the presence of phenolic compounds with antioxidant activity in the linseed oil. The results obtained indicate the need for more detailed studies, given the importance of linseed oil as one of the greatest sources of ω3 among vegetable oils
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La dificultad que los alumnos encuentran en el aprendizaje de matemática viene siendo objeto de investigación por estudiosos en educación matemática, tanto en Brasil como en el exterior. El objetivo de este estudio consiste em investigar las dificuldades en el aprendizado sobre funciones matemáticas y la influencia de las concepciones alternativas a partir de los errores que los candidatos acerca de las cuestiones sobre funciones en la prueba objetiva de matemática del acceso a la universidad de los años de 2001 a 2008. Teniendo como cuestiones de estudio para alcanzar el objetivo propuesto: identificar la relevancia del tema funciones que son contemplados en las pruebas de acceso a la Universidad; asi como cuáles han sido los tipos de funciones más privilegiados y menos privilegiados; analizar si la contextualización de la pregunta y la presencia de elementos no textuales han influenciado en el aumento de tal dificultad; analizar si la representación semiótica agrega mayor exigencia a la pregunta; analizar respecto a la exigencia matemática de la pregunta; analizar lo que se refiere al desempeño de los candidatos para verificar cuál pregunta tuvo mejor desempeño y cuál el peor e identificar los errores más frecuentemente cometidos por los candidatos en esas pruebas. Las reflexiones de los estudiosos como: Radatz (1980), Cury (1994), Socas (1997), Borasi (1997), Franchi e Rincón (2004), Pochulu (2004) presentan las dificultades en el aprendizaje matemático, que aparecen a partir de los errores cometidos por los alumnos, quando estos errores reciben la influencia de las concepciones alternativas. El estudio que se presenta en esta disertación configura un análisis de los errores que los candidatos han cometido en las preguntas objetivas sobre el tema funciones de las pruebas de acceso a la Universidad de los años de 2001 a 2008, a partir de los relatorios de la Comissão Permanente do Vestibular COMPERVE/UFRN. Con la intención de alcanzar los objetivos propuestos para este estudio, fueran sido construidas categorías de análisis. Los resultados encontrados han sido: El tema funciones es el más frecuente entre los demás con (28,1%); el tipo de función priorizada durante esos años ha sido la función logarítmica con (24%); la contextualización de las preguntas exige una mayor comprensión por parte del candidato de lo que las situaciones directas; la caracterización semiótica posee elementos que estructuran esas preguntas que el educando debe saber asociar al texto; la exigencia matemática posibilitó analizar que el procedimiento medio ha sido el más requisitado; el desempeño de los candidatos ha sido en la mayoría bajo (50%); y los principales errores que ellos han cometido han sido de realizar traducciones incorrectas de las expresiones que aparecen en las situaciones-problema; utilizar todos los datos que aparezcan en el problema sin tomar en cuenta si el cálculo realizado responde a la pregunta solicitada; no interpretar coherentemente las informaciones del gráfico; decodificar incorrectamente los valores representados por literales en una recta numérica. Los resultados señalizan la necesidad de una revisión didáctico-metodológicas de la enseñanza de funciones a raíz de las cuales las dificultades en el aprendizaje se han presentado
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
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This dissertation aims at characterizing the practices as well as the effects of a teacher s feedback in oral conversation interaction with students in an English Language classroom at a Primary School, 6th Grade in Açu/RN, Brazil. Therefore, this study is based on Vygotsky s (1975) and Bruner´s (1976) researches, which state that the learning process is constructed through interaction between a more experienced individual (teacher, parents and friends) and a learner who plays an active role, a re-constructor of knowledge. It is also based on Ur´s (2006) and Brookhart s (2008) studies (among other authors in Applied Linguistic) who defend that the feedback process needs to be evaluative and formative since it sets interfaces with both students autonomy and learning improvement. Our study is based on qualitative, quantitative and interpretive researches, whose natural environment (the classroom) is a direct source of data generated in this research through field observations/note-taking as well as through the transcriptions of five English classes audio taped. This study shows the following results: the teacher still seems to accept the patterns of interaction in the classroom that correspond to the IRE process (Initiation, Response, Evaluation) in behaviorist patterns: (1) he speaks and determines the turns of speech; (2) the teacher asks more questions and directs the activities most of the time; (3) the teacher´s feedback presents the following types: questioning, modeling, repeated response, praise, depreciation, positive/negative and sarcasm feedback, whose functions are to assess students' performance based on the rightness and wrongness of their responses. Thus, this implies to state that the feedback does not seem to help students improvement in terms of acquiring knowledge because of its normative effects/roles. Therefore, it is the teacher´s role to give evaluative and formative feedback to a student so that he/she should advance in the learning of the language and in the construction of knowledge
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Este trabalho tem como foco principal a interação em sala de aula, especificando aspectos da organização linguístico-discursiva, na produção conjunta da fala da professora e dos alunos, materializada em turnos, ressaltando o par pergunta-resposta na aula de Língua Portuguesa. Para alcançarmos esse objetivo, inspiramo-nos em alguns trabalhos acerca da organização da interação que adotaram a perspectiva dos estudos interacionais e a abordagem etnográfica, a fim de explicitar o conhecimento nos espaços de ensino e aprendizagem. Entre eles, citamos as pesquisas de Galvão (1996, 2004) e de Matêncio (2001). Nessa direção, descrevemos o processo de interação em sala de aula em uma escola pública, analisando e interpretando as ações de linguagem realizadas pela professora e pelos alunos. Teoricamente, embasamo-nos, principalmente, na Análise da Conversação, ancorando-nos no estudo pioneiro de Sacks, Schegloff e Jefferson ([1974] 2003); nos postulados de Marcuschi ([1986] 2007a); nas pesquisas de Kerbrat-Orecchioni (2006), dentre outros. Explicitamos uma tipologia de perguntas e respostas em sala de aula, quanto à sua forma e função, conforme os postulados teóricos de Stubbs (1987), Araújo (2003), Fávero, Andrade e Aquino (2006), Silva (2006) e Koshik (2010). Analisamos a organização da tomada de turno, seguida de uma investigação sobre perguntas e respostas no discurso desenvolvido face a face. Na tentativa de compreendermos o cotidiano dos envolvidos no cenário de sala de aula, adotamos a abordagem etnográfica e o método indutivo, nas perspectivas de André (2010) e Chizzotti (2006). Os dados foram gerados através de pesquisa de campo, por meio de gravações (em áudio) de aulas de Língua Portuguesa, posteriormente transcritas e transformadas no corpus de pesquisa. As análises demonstraram que a interação entre professora e alunos organizou-se em trocas de turnos, na maioria das vezes, controladas pela professora, evidenciando-se uma relação de assimetria entre os participantes. Esses turnos concretizados, geralmente, no par adjacente pergunta-resposta revelaram como a construção do conhecimento se realiza em sala de aula. Por fim, observamos que a interação em sala de aula de Língua Portuguesa é organizada por aspectos sociais e pedagógicos intrinsecamente imbricados
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Through a careful examination of the relationship between Zoroastrianism and the Western tradition, and a detailed and critical reading of the writings of Nietzsche, this work aims at showing to what extent the character Zarathustra , his discourses and poetical-philosophical thoughts, and related passages from many distinct Nietzschean works, directly or undirectly reflect a philosophy that harvests contributions from the Zoroastrian tradition or its headways (in the Judeo-Greco-Christian tradition, and furthermore in the whole Western philosophical tradition). Supplied with this provisions, and with the interpretation cast upon them, Nietzschean philosophy questions the entire Western tradition of thought, and proposes its replacement by a new attitude towards life. This work also intends to show the way the Nietzschean Zarathustra was built up, in the writings of the German philosopher, together with the idea of making, out of the namesake character of the ancient Iranian prophet (Zarathushtra or Zoroaster, the founder of Zoroastrianism), the herald of that important text that intended to bring the German language to its highest perfection , clumping together, and leading to a prophetic-poetic climax consonant with the meaning of the Earth , Nietzsche s key ideas about the rectification of the most fatal of errors and about the death of God . An elaborate investigation has been pursued after the reasons and manners of the building up of Nietzsche s Zarathustra mirroring its Iranian namesake (sections 1.1 to 1.6), and a survey of the works of Nietzsche has suggested unquestionable relations with the Zoroastrian tradition, mostly through the Jewish, Greek or Christian repercussions of this tradition. These relations have been put in context, in many framings (sections 2.1 to 2.3.2), in the ambit of the most fatal of errors - the - creation of morals in the very occasion of its transposition to metaphysics (Ecce Homo, Why I am a destiny , 3). Through an evaluation of the possible circumstances and repercussions of the death of God , the relations between Nietzsche s writings and Zoroastrian tradition have been investigated (sections 3.1 to 3.7), allowing the understanding of this event as an essential component, and tragic outcome, of the rectification of the most fatal of errors
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Exercise-induced muscle damage mainly affects individuals who returned to physical activity after a time without practicing it or had some kind of exhaustive exercise, particularly eccentric exercise. To evaluate the effect of cryotherapy and laser therapy in response to muscle damage induced by eccentric exercise on the biceps muscle. This was a randomized clinical trial consisting of 60 female subjects. All subjects initially underwent an evaluation consisting of perimetry, measurement of pain sensation (via algometry and visual analogue scale), electromyography and dynamometry. Then the subjects performed an exercise protocol on the isokinetic dynamometer consisting of 2 sets of 10 eccentric elbow flexors contraction at 60 °/s. Completed this protocol, an intervention was held according to a previously random group distribution: control group (no intervention), cryotherapy group and laser therapy group. Finally, subjects were re-evaluated immediately and 48 hours after the intervention protocol, except for Visual Analogue Scale (VAS), which was also evaluated 24 hours after exercise. The circumference of the limb, the pain sensation (VAS and algometry), the muscle activation amplitude (via Root Mean Square - RMS), median frequency, peak torque normalized per body weight, average peak torque, power and work were analyzed. The median frequency immediately after the intervention protocol on the cryotherapy group was the only variable that showed inter and intra-group differences; the remaining variables showed only intragroup differences. The perimetry values did not change immediately after the protocol on the groups which underwent cryotherapy and laser therapy, however, there was an increase after 48 hours; algometry values decreased in all groups for 48 hours and the VAS values increased 24 and 48 hours also for all groups. Regarding RMS no significant change was observed. For dynamometry, peak torque normalized per body weight and average peak torque had a similar behavior, with a reduction in the post protocol that has remained after 48 hours. For the power and work, a decrease was observed immediately after the protocol with a further reduction after 48 hours. Cryotherapy and laser therapy does not alter the muscle damage response, except for the perimetry values immediately after exercise.
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Th17 cells have been strongly associated with the pathogenesis of several autoimmune and inflammatory diseases. IL-17 and IL-23 are important cytokines associated with this lineage. The aim of this study was to analyze, through immunohistochemical methods, the immunoexpression of IL-17 and IL-23 in the inflammatory infiltrate of oral lichen planus (OLP) lesion compared to that of inflammatory fibrous hyperplasia (IFH) and between clinical forms reticular and erosive of OLP. The sample included 41 cases of OLP, of which 23 were reticular and 18 erosive and 10 cases of IFH. The results were subjected to nonparametric statistical tests with a 5% significance level. In OLP lesions histomorphological analysis, the most common findings were: hyperparakeratinization, specimens with atrophic epithelium in erosive clinical form (p = 0.011), epithelial projections in most of reticular type of lesions, in addition Civatte bodies were identified in most samples of both clinical forms. For immunohistochemistry analysis, five fields with strong immunoreactivity for IL-17 and IL-23 were photomicrographed at 400x magnification, images were transferred to a computer where with ImageJ software®, lymphocytes that exhibited cytoplasmic immunostaining for these cytokines were counted. A mean was established after for each case. There was no statistically significant difference in the number of imunopositive lymphocytes for IL-17 and IL-23 among the group of OLP and IFH group, however a larger amount of lymphocytes imunopositive for IL-17 was found in the LPO group (p = 0.079) and significantly higher amounts of those lymphocytes were found in the erosive OLP when compared to the group of reticular OLP and IFH (p = 0.019). Furthermore, a marker epithelial immunopositivity for IL-17 was observed in OLP group. Although the results of this study do not permit the forceful assertion about the participation of Th17 lineage in OLP lesions, the findings of immunopositive lymphocytes counting for IL-17 and IL-23, which are potent proinflammatory cytokines, together with the the marked epithelial immunopositivity found for IL-17 in this study, suggest a possible role of this lineage in the pathogenesis of this disorder