53 resultados para Descriptive quantitative analysis
Resumo:
Attention to the health of adolescents, based on paradigm flexneriano, needs to be overcome. Since the International Conference of Ottawa (1986), the literature is developing a discussion of the promotion of health, based on the paradigm of social production in health, suggests a design to overcome the health care traditional practices. Program Health of the Family PSF has this purpose to transmute the model of existing assistance, where the nurse is an essential element to the work done in the program. Around this context, it is our purpose to analyze the practice of nurse of the PSF for the promotion of health of adolescents, produced by a search of descriptive quantitative approach with the inclusion of qualitative data. Interviews were conducted with 9 nurses 3 units of health of the family USF, Mossoró-RN and applied questionnaires with 74 teenagers aged between 15 and 19 years old, with some nearby public schools where USF operate these nurses. The quantitative descriptions were transformed on tables, pictures and graphics using the program Excel (Microsoft) and the qualitative were worked through the technique of analyzing the content of Bardin (2004). The review was realized using the reference to promote health brought by the study. The results show that the most common problems that happen with teenagers are the drugs (33,8%), pregnancy (27,0%) and political problems-socio-economic-cultural issues (24,3%). Adolescents are spontaneous demand and rarely seek the USF. The actions presented by the nurses as, lectures and groups, are nothing comparing to the macro-problems presented by adolescents, and verticalized irregular. The nurses know the promotion of health generally, not explaining how operate it from its daily practice. Concluded that the practice of nurse of the PSF has not yet reach the promotion of health of the adolescent, being necessary to scheduling modules on the subject to continuous training of teams, professionals from USF, as well as teachers and other staff of schools, giving space to the participation of academic. The discussions should be socialized with the community to discuss possibilities of confrontation of the problems, which also require socio-structural changes. This research can contribute as work-diagnosis, which experienced the reality of care in nursing PSF to a specific group
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The objective of this exploratory descriptive quantitative study was to analyze the behaviors in the detection, treatment and followup of the pregnant woman with syphilis, by health professionals that conduct the pre-natal consultation in the Family Health Strategy, as to the adherence to the recommendations of the Ministry of Health. The study was conducted in nine municipalites of the Trairi region in the state of Rio Grande do Norte. Data were collected during the months of July through September 2007, by means of a questionnaire with a population of 53 health professionals, 30 nurses and 23 physicians. Data were analyzed by descriptive statistics. The results were organized in three major items: knowledge of the health professionals about the symptomatology of syphilis and their actions in the detection of the disease; actions in the treatment of the pregnant woman with syphilis; and the actions of followup of the desease. We identified that 81,2% of the professionals have knowledge about the symptomatology of syphilis in the pregnant woman;79,2% request the VDRL exam in the adequate intervals and approximately 50% conduct the treatment in conformity with the recommendations of the Ministry of Health. For the followup care of the infected woman, 79,2% request a monthly VDRL examination, 69,8% explain the disease to the pregnant woman, and 20,7% affirm that they conduct a proper reception to the woman.We conclude that the majority of the health professionals have knowledge of the detection, treatment and followup of the pregnant woman with syphilis. However, the actions of some professionals diverge from the conduct procedures recommended by the Ministry of Health, as to the requesting of the examinations, medication prescription and notification of the iesease. This indicates the need for improved
Resumo:
A descriptive, quantitative approach and non-participant observation study, which was aimed at analyzing the association between knowledge and practice of inclusion and maintenance of urinary catheter by nursing professionals in the occurrence of urinary tract infection, performed in the ICU of Onofre Lopes University Hospital in Natal / RN. The original sample was composed of 42 nursing staff professional, five (5) nurses and 37 nursing technicians, 27 of them were outsourced (FUNPEC and IEL fellows) and 10 servers UFRN. Data collection was performed using two instruments, the first observation procedures used in the insertion and manipulation of indwelling urinary catheter (IUC) and the second with a questionnaire that addressed the characterization data of respondents, knowledge and conduct the insertion and manipulation of the IUC. The results were tabulated in Microsoft Excel and analyzed using SPSS software, version 15.0. We found the prevalence of institutional staff members on outsourcing - IEL and FUNPEC - (64.3%) were female (69.0%), aged 21 to 35 years (59.5%) and with mid-level education (88.1%). As to knowledge, we found that the nurses had levels of good to excellent and the nursing technicians, to regulate the poor. The nurses made a mistake when choosing IUC (40.0%) and washing hands (30.0%) and technicians on hand washing (74.4%) and the contents of the tray (34.7%). In relation to the conduct of insertion of IUC, the nurses made a mistake when choosing SVD (66.7%) and washing hands (57.1%). Regarding the handling of IUC/drainage system, the technicians were wrong more about washing their hands (56.0%). Analyzing the misconduct to the categorization of knowledge, we saw that the nursing staff who had missed more had inadequate knowledge (ρ = 0.001). At the end we found the risk of a patient to acquire UTI is higher in two and a half times when there is a large number of mismatches, patient spends more time using the IUC and hospitalized in the ICU. As regards the study hypotheses, we accept the alternative hypothesis and reject the null hypothesis proposed at the start of this research, where the number of gaps in knowledge and behavior increases the incidence of urinary tract infection.
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This study aimed to validate tools for evaluating the ability and knowledge about blood pressure (BP) among nursing students. It is a cross-sectional, descriptive, quantitative and methodological study accomplished at the Universidade Federal do Rio Grande do Norte (UFRN), Universidade do Estado do Rio Grande do Norte (UERN) and a private university of the state. The sample consisted of 27 judges of research selected from the inclusion criteria: nursing, teachers of the semiology and/or semiotics discipline, with at least 1 year of experience, being from UFRN, EEN, UERN and private university of the state and and agree to participate voluntarily with the signing of the consent form. The research was development in three stages: construction of two instruments based on the scientific literature, resulting in a structured checklist consists of 28 items and a knowledge questionnaire with 12 questions; submission of the instruments to the judges, in the period from June to September 2012, which should evaluate each item in appropriate , appropriate with changes and inappropriate , addition to making an overall assessment of each instrument based on 10 requirements; validation and verification to the level of agreement among the judges, through the application of Kappa and Content Validity Index (CVI). Was used the consensus level greater than 0.61 (good) to the Kappa index and greater than 0.75 for CVI. Was approved by the Ethics in Research / HUOL. After being coded and tabulated, the data were analyzed using descriptive statistics. Of the 27 judges who evaluated the instrument, 77.8% are female, with a mean age of 36.6 (± 9.0) years, 63.0% worked in UFRN, 74.1% had academic master and 63.0% worked exclusively on teaching. Average length of teaching experience was 7.9 (± 8.0) years and in the semiology and/or semiotics discipline of 5.5 (± 6.7) years. In the judgment of structured checklist and questionnaire of knowledge about blood pressure mensurement any item/question was considered inappropriate since all obtained level of agreement within the indices established (CVI> 0,75 E Kappa> 0.61). In relation to structured checklist, of those 28 items present, 9 showed perfect concordance index (CVI = 1.00, Kappa = 1.00) and another 19 were considered appropriate with changes, especially with regard to clarity and vocabulary. In the questionnaire of knowledge, among the 12 questions that comprised, 7 had perfect concordance index and the others were considered appropriate with changes as requirements as clarity, vocabulary, and feasible sequence of instructional topics. In terms of a overall evaluating of instruments, the structured checklist got CVI of 0.94 and Kappa of 0.89 and the knowledge questionnaire, CVI of 0.97 and a kappa of 0.94. Both instruments proved to be valid as to their content, configuring it as clear and objective tools of assessment of knowledge and ability on blood pressure, being of nursing students as well as others students and health professionals, since the use of valid measures seeking to reduce the risk of distorting the results
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That study had the aim to validate an instrument to evaluate the knowledge about the Urinary Catheterization (UC) in males. Cross-sectional, descriptive, quantitative and methodological study, accomplished in Universidade Federal do Rio Grande do Norte (UFRN), Universidade do Estado do Rio Grande do Norte (UERN) and a private university from Rio Grande do Norte. Sample of 27 judges selected from the inclusion criteria: registered nurses, discipline of semiology and/or semiotics teachers, with at least 1 year of experience in the disciplines, to work at UFRN, UERN or in private university and agree to participate voluntarily with the signing of the Consent Form. Study developed in three stages: a) elaboration of twos instruments based on the scientific literature, resulting in a structured observation script type checklist consisting of 36 items and a knowledge questionnaire with 12 questions; b) submission of instruments to judges from June to September 2012, which should evaluate each item in "adequate," "adequate with changes" and "inappropriate", and make an overall evaluation of each instrument based on 10 requirements; c) and validation with a verification of the agreement level among the judges, through the application of Kappa Index (K) and Content Validity Index (CVI). It was used the consensus level higher than 0.60 (good) for Kappa Index and higher than 0.70 for CVI. The research project had favorable opinion from the Ethics in Research/HUOL (CAAE n. 0002.0.294.000-10). After being coded and tabulated, the data were analyzed using descriptive statistics. Of the 27 judges who evaluated the instrument, 77.8% are female, with a mean age of 36.6 (± 9.0) years, 63.0% worked in UFRN, 74.1% had master degree and 63.0% worked exclusively on teaching. The experience time mean in teaching was 7.9 (± 8.0) years and in the disciplines of semiology and/or semiotics in nursing was 5.5 (± 6.7) years. In judgment of the checklist and knowledge questionnaire, no step/question was considered inappropriate, since all achieved level of agreement within the established values. All the checklist steps obtained good to excellent K (between 0.60 and 1.00). Of the 36 items, 25 had excellent K (0.75 ≤ K <1.00) and excellent total K (K = 0.83). Regarding the IVC, all steps reached levels above 0.70 (between 0.74 and 1.00) and CVI total was 0.90. All questionnaire questions evaluated separately (K from 0.60 to 0.93 and CVI from 0.74 to 0.96) and generally (K from 0.79 to 1.00 and CVI from 0.89 to 1.00) had evaluation levels of content validity within the established values. The instruments were reformulated based on the agreement levels between judges and international guidelines, dissertations and scientific articles. Both instruments proved to be valid regarding to their content, allowing a clear and objective evaluation of knowledge and skills about UC, both nursing students as well as other students and health professionals, since the use of valid measures seeking the reduction of the risk of the results distorted
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ln this work the implementation of the SOM (Self Organizing Maps) algorithm or Kohonen neural network is presented in the form of hierarchical structures, applied to the compression of images. The main objective of this approach is to develop an Hierarchical SOM algorithm with static structure and another one with dynamic structure to generate codebooks (books of codes) in the process of the image Vector Quantization (VQ), reducing the time of processing and obtaining a good rate of compression of images with a minimum degradation of the quality in relation to the original image. Both self-organizing neural networks developed here, were denominated HSOM, for static case, and DHSOM, for the dynamic case. ln the first form, the hierarchical structure is previously defined and in the later this structure grows in an automatic way in agreement with heuristic rules that explore the data of the training group without use of external parameters. For the network, the heuristic mIes determine the dynamics of growth, the pruning of ramifications criteria, the flexibility and the size of children maps. The LBO (Linde-Buzo-Oray) algorithm or K-means, one ofthe more used algorithms to develop codebook for Vector Quantization, was used together with the algorithm of Kohonen in its basic form, that is, not hierarchical, as a reference to compare the performance of the algorithms here proposed. A performance analysis between the two hierarchical structures is also accomplished in this work. The efficiency of the proposed processing is verified by the reduction in the complexity computational compared to the traditional algorithms, as well as, through the quantitative analysis of the images reconstructed in function of the parameters: (PSNR) peak signal-to-noise ratio and (MSE) medium squared error
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Licuri is a palm tree from the semiarid regions of Bahia State, Brazil. It is an important source of food and feed in that region, since their nuts are commonly eaten by humans and used as maize substitute for poultry feeding. The aim of this dissertation is to study the feasibility for use of natural convection solar dryers and forced being compared with the traditional drying outdoors for drying coconut licuri Syagrus coronate. The study led to the construction of two prototype solar dryer for carrying out experiments proving: model Solar Drying System Direct Exposure to Natural Convection built with wood, has a drying chamber with direct cover transparent glass laminates 4 mm, using techniques for proper isolation of the drying chamber. The two prototypes were comparatively analyzed for performance and drying efficiency with traditional extractive use by the community. Were evaluated the variables: time and drying rates and quality of the final samples of coconut licuri. The fruits were harvested and brought the town of Ouricuri, in the city of Caldeirão Grande, BA for the experiments comparing the three methods of drying was used a standard load of 4.0 kg The quantitative analysis for the result of the drying rate was found in 74% yield and 44% for natural and forced convection respectively compared with the traditional drying. These drying rates represent variation 3-5 times lower. Drying using forced convection licuri showed better quality, was found in a reddish pulp, representing the quantities that were kept of the nutrient beta carotene, and not notice the flavor change from the previous system, the final cost of construction of this system were higher . The prototypes built competitive advantage and had testified fully to resolve the technical difficulties previously encountered in the production of products made of coconut licuri. Allowing add value and increase their potential use for the fruit extractive communities of semi-arid region of Bahia
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Massively Multiplayer Online Role-Playing Games (MMORPGs) are role-playing games that, through the Internet, can integrate thousands of players interacting at the same time in at least one virtual world. This way, these games can provide, further than fun, a greater familiarity with the additional language and opportunity to improve the linguistic proficiency in a real context. Hence, what is proposed in this study is extended knowledge about the learning of an additional language mediated by MMORPGs for teachers to know how, if relevant, to present, use or encourage this practice to their students. Based on this major purpose, we seek to answer the following research questions: (a) what distinguishes the learning profile of the gamers and non-gamers; (b) if MMORPGs can, through a hybrid and systematic approach, assist the development of proficiency of the additional language and (c) what the think-aloud protocols show about the learning mediated by the MMORPG Allods Online. Following an experimental method (NUNAN, 1997), 16 students of the curricular component Reading and Writing Practices in English Language have comprised the control group and 17 students of the same class formed the experimental group and were submitted to a pre and post-test adapted from the Key English Test (KET) by the Cambridge University (2008). The tests were conducted before and after a period of 5 weeks of 3 hours of practice with Allods Online a week (experimental group), and classes of the curricular component (both groups). A quantitative analysis of the questionnaires about the exposure to English profiles of the participants, a quantitative analysis of the tests scores and a qualitative analysis of the thinkaloud protocols collected during the experiment were conducted based on the theories of (a) motivation (GARDNER, 1985, WILLIAMS & BURDEN, 1997, BROWN, 2007, HERCULANO-HOUZEL, 2005); (b) active learning (GASS, 1997, GEE, 2008, MATTAR, 2010); (c) interaction and collaborative learning (KRASHEN, 1991, GASS, 1997, VYGOTSKY, 1978); (d) situated learning (DAMASIO, 1994; 1999; 2003, BROWN, 2007, GEE, 2003) and (e), tangential learning (PORTNOW, 2008; MATTAR, 2010). The results indicate that the participants of the experimental group (gamers) seem to be more engaged in tangential English learning activities, such as playing games, listening to music in English, communicating with foreigners and reading in English. We also deduced that the period of experiment possibly generated positive results on the gamers proficiency scores, mainly in the parts related to orthographic development, reading and comprehension, writing with focus on content and orthographic accuracy. Lastly, the think-aloud protocols presented evidences that the gamers have engaged in active English language learning, they have interacted in English with other players, and learned linguistic aspects through the experience with the MMORPG Allods Online
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In this dissertation, based on two theoretical frameworks, American functionalism and variationist sociolinguistics, I take as subject the sequence connectors E and AÍ, which has the grammatical function of indicating retroactive-propeller sequenciation of information. I analyze the variable use of these connectors in texts written by students from two public schools in the city of Natal, RN, attending at the time of data collection (the year 2012), two distinct levels of basic education: the sixth and the ninth year. The students who contributed to this research wrote, as part of their activities in the classroom, texts of two narrative genres: narrative of personal experience (non-fictional) and short story (fictional). In addition, these students and their Portuguese teachers answered a test of linguistic attitude in which they gave their opinions regarding the appropriateness of the use of connectors E and AÍ in contexts of speech and writing marked by distinct degrees of formality. The results obtained by means of quantitative analysis showed different tendencies of linguistic, social and stylistic distribution of connectors E and AÍ in the narrative texts written by the students. I related these results to the action of two principles: the principle of persistence, linked to the process of change by grammaticalization, and the principle of stylistic markedness. Besides, I took into account the answers provided by students and teachers to the test of linguistic attitude for refine the interpretation of the results
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We study the optical-phonon spectra in periodic and quasiperiodic (Fibonacci type) superlattices made up from III-V nitride materials (GaN and AlN) intercalated by a dielectric material (silica - SiO2). Due to the misalignments between the silica and the GaN, AlN layers that can lead to threading dislocation of densities as high as 1010 cm−1, and a significant lattice mismatch (_ 14%), the phonon dynamics is described by a coupled elastic and electromagnetic equations beyond the continuum dielectric model, stressing the importance of the piezoelectric polarization field in a strained condition. We use a transfer-matrix treatment to simplify the algebra, which would be otherwise quite complicated, allowing a neat analytical expressions for the phonon dispersion relation. Furthermore, a quantitative analysis of the localization and magnitude of the allowed band widths in the optical phonon s spectra, as well as their scale law are presented and discussed
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In this work, we present a theoretical study of the propagation of electromagnetic waves in multilayer structures called Photonic Crystals. For this purpose, we investigate the phonon-polariton band gaps in periodic and quasi-periodic (Fibonacci-type) multilayers made up of both positive and negative refractive index materials in the terahertz (THz) region. The behavior of the polaritonic band gaps as a function of the multilayer period is investigated systematically. We use a theoretical model based on the formalism of transfer matrix in order to simplify the algebra involved in obtaining the dispersion relation of phonon-polaritons (bulk and surface modes). We also present a quantitative analysis of the results, pointing out the distribution of the allowed polaritonic bandwidths for high Fibonacci generations, which gives good insight about their localization and power laws. We calculate the emittance spectrum of the electromagnetic radiation, in THZ frequency, normally and obliquely incident (s and p polarized modes) on a one-dimensional multilayer structure composed of positive and negative refractive index materials organized periodically and quasi-periodically. We model the negative refractive index material by a effective medium whose electric permittivity is characterized by a phonon-polariton frequency dependent dielectric function, while for the magnetic permeability we have a Drude like frequency-dependent function. Similarity to the one-dimensional photonic crystal, this layered effective medium, called polaritonic Crystals, allow us the control of the electromagnetic propagation, generating regions named polaritonic bandgap. The emittance spectra are determined by means of a well known theoretical model based on Kirchoff s second law, together with a transfer matrix formalism. Our results shows that the omnidirectional band gaps will appear in the THz regime, in a well defined interval, that are independent of polarization in periodic case as well as in quasiperiodic case
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The Specialized Dental Care Centers (CEO) were developed to provide specialized dental care to the population, given the accumulated needs of health since the past. They must operate as units of reference for the Oral Health Team of the Primary Care, complementing the dental procedures performed at this level of attention. This study aims to assess the performance of CEOs of the Grande Natal Health Region as a strategy of Secondary Care consolidation in oral health through users, dentists and managers. For this to try to identify factors about access, hosting and satisfaction with the service, the actions developed in these centers, integration between the CEOs and the Basic Health Units (UBS), considering the reference and counter reference. Data were collected through semi-structured interview, conducted in four CEOs, among 253 users, 31 dentists and 4 managers. It was submitted to descriptive statistical analysis and to content analysis by software ALCESTE 4.5. The results revealed that the specialties of prosthesis, endodontics and surgery were the most sought by 38.2%, 23.7% and 21.7% of respondents, respectively. It was noticed that among users aged 18 to 30 years-old the greatest demand is for the specialty of endodontics (44.4%) and over 50 years for prosthesis (76.4%). There is a weakness in the reference and counter reference between UBS and CEO, because part of users goes directly to the centers without going before to the Primary Care and the majority does not want to return to the dentist of Health Unit. Satisfaction with care was reported by 90.9% of users, because they resolved the problems needed and were welcomed by the team. But the delay in care was the main factor for not satisfaction. For most dentists, some users could solve their problems completely in Primary Care, which shows the existence of unnecessary referrals to the CEOs, however they consider the existence of limiting factors in UBS that compromise the service. Most dentists revealed that some users do not get to CEOs with the basic dental treatment done, and some of them do not counter reference users. It can be concluded that the studied CEOs are being resolutive for those who access them, offering necessary care for the population, and if they don t account with this service, will encounter obstacles to resolution of problems, ranging seek care service in particular, in another public sector, or even giving up treatment. However, it is perceived the need of professionals training to understand the importance of the reference and counter reference, to that they can better serve and guide users. It is also important that cities offer better conditions to UBS and CEOs, so they can work together, with complementary actions of oral health, seeking full care, aiming for better resolution to the users' health problems
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The most common malignant neoplasm of the oral cavity and oropharynx are squamous cell carcinoma. Injuries to the same stage and subjected to the same treatment protocol have sometimes different evolutionary courses. The scope of this study was to investigate, through a retrospective cohort, associations between the number of CD8 + T cells and natural killer, identified immunohistochemically in the inflammatory infiltrate in a series of cases of oral squamous cell carcinoma and orofaringeano, and the level of tumor response to radiotherapy and chemotherapy, overall survival and relapse-free survival of patients. We identified 54 patients with unresectable disease were treated exclusively with radiotherapy and chemotherapy. The median follow-up was 22 months. The sample was characterized by the predominance of male subjects, median age 60 years, all were smokers. The most frequent site was the tongue and 81.5% were in stage IV. Patients with disease in the oral cavity had a worse response to treatment (p = 0.006), worse relapse-free survival (p = 0.007), worse overall survival (p = 0.007). The advanced T stage was shown a negative prognostic factor (p= 0.006) for the clinical treatment response made. Immunohistochemistry was performed to select CD8 + cells (anti-CD8) and NK cells (anti-CD57). Lymphocytes positive and negative markings were counted using the program ImageJ ®. Two groups were created for each marking evaluated: Group I patients with more than 50% cells positive, Group II: less than 50% of labeled cells. For CD8 + cells detected in 38 (70.3%) of Group I were CD8 + and 16 (29.7%) Group II CD8 +. For NK cells, 26 (48.15%) Group I NK and 28 (51.85%) Group II NK. Regarding the clinical response to treatment, we observed that 39% of patients achieved a complete response and 25.9% remained without recurrence at the end of follow-up. These results were better in Group I CD8 + (p = 0.2). Identified that 72.2% of patients progressed to death, this finding had no association with the immunohistochemical data. There was no statistically significant differences between the number of CD8 + and NK cells and the ability of tumor response to radiotherapy and chemotherapy, or with overall survival and relapse-free survival of patients. However, especially in relation to a learned response, we found that this group of patients with advanced disease have a low count of CD8 + T cells active. Believing in the role that the immune response plays in the local fight against neoplastic cells, however, our results do not support the use of quantitative analysis of CD8 + T cells and NK cells as a prognostic factors for oral squamous cell carcinoma and oropharynx
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The odontogenic myxoma shares cellular and structural aspects with dental papilla, which has been implicated as probable origin of this neoplasm. The aim of the present study was to perform a comparative immunohistochemical analysis for the expression of collagenase-1 (MMP-1) and gelatinases A (MMP-2) and B (MMP-9) in odontogenic myxomas and dental papilla of teeth germs. Twelve cases of odontogenic myxomas and eight specimens of teeth germs were selected. It was taken into consideration the presence or absence of immunoreactivity, the pattern of immunohistochemical distribution of proteases within extracellular matrix, as well as, the number of cells revealing immunostaining for matrix metalloproteinases (MMPs). It was verified a significant difference (p<0,05) in relation to MMP-2 immunoexpression, which was observed only within extracellular matrix of myxomas. Nevertheless, MMP-1 labeling was revealed by most of the cases of odontogenic myxoma, at levels close to those observed in dental papilla. In relation to the pattern of distribution, a significant difference was obtained between specimens (p<0,05), with neoplasms predominantly exhibiting a focal pattern for MMP-1. The quantitative analysis of neoplastic cells labeled for MMPs denoted a significant difference (p<0,05), demonstrating a higher proportion of MMP-1 in comparison to MMPs-2 and -9. It can be concluded that immunohistochemical expression of MMP-1 at levels comparable to those observed in dental papilla and quantitatively superior in relation to MMPs-2 and -9, suggest an implication of this protease on extracellular matrix degradation of odontogenic myxomas. Moreover, the possibility of interactions with receptors involved in cellular adhesion, particularly with integrins, suggests a plausible function on local invasiveness of such neoplasms. Additionally, the presence of a descent immunoexpression gradient for these MMPs on odontogenic myxomas, associated to substrate specificity inherent in each enzyme, suggest the existence of a coordinated mechanism between interstitial collagenase and gelatinases A and B in order to allow an efficient degradation of extracellular matrix and local invasion by neoplastic cells
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Ameloblastomas and keratocystic odontogenic tumors (KOT) represent odontogenic lesions that, despite their benign nature, are distinguished by a distinct biological behavior, characterized by locally aggressive growth and recurrent episodes. The gnathic bone resorption caused by the growth of these lesions is a key to the expansion of the same, both being mediated by osteoclastic cells like enzymatic activity of various matrix metalloproteinases (MMPs) factor. The expression of stimulatory factors and inhibitors of bone resorption has been correlated with the development of these lesions, with emphasis to some MMPs such as collagenases and gelatinases and tissue inhibitors of metalloproteinases (TIMPs), among others. Based on the premise that stimulatory and inhibitory factors of osteolytic processes can be decisive for the growth rate of intraosseous odontogenic lesions, this experiment evaluated the immunoreactivity of MMP-9, -13 and TIMP-1 protein in the epithelium and mesenchyme of ameloblastoma and the KOT specimens, by a quantitative analysis of the immunoreactivity cells. Statistical analysis was performed using the Mann-Whitney and Wilcoxon tests with a significance level set at 5 %. Immunohistochemical expression of MMP-9, -13 and TIMP-1 was observed in 100% of cases both in the epithelium and in mesenchyme. The immunoreactivity in the epithelium of KOT and ameloblastomas revealed a predominance of score 3 for MMP-9 (p=0.382) and MMP-13 (p=0.069) and no statistically significance for TIMP-1, the latter being significantly higher immunoreactivity in ameloblastomas. In the mesenchyme, there was a higher score immunoreactivity of MMP-13 (p=0.031) in ameloblastomas in relation to KOT, whereas for MMP-9 and TIMP-1 no statistically significant difference (p=0.403 was observed, p=1.000). The calculation of the ratio of scores revealed expression of proteins in general, similarity of the lesions, a significant predominance of equal expression of TIMP-1 and MMP-9 was observed only in the epithelium of ameloblastoma. The marked immunostaining of MMP-9 , MMP-13 and TIMP-1 in epithelium and mesenchyme of the lesion indicate that these proteins involved in ECM remodeling required for tumor progression, however, specific differences in the expression of some of these proteins, are not sufficient to suggest differences in the biological behavior of ameloblastomas and KOTs