267 resultados para parafina


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Objetivo: avaliar os efeitos de precondicionamento isquêmico remoto (PCI-R) no modelo de transplante de intestino delgado fetal. Métodos: foram constituídos dois grupos: transplante isogênico (Iso, camundongos C57BL/6, n=24) e transplante alogênico (Alo, camundongos BALB/c, n=24). Em cada grupo, distribuíram-se os animais com e sem PCI-R, que foi realizado por oclusão da artéria femoral esquerda da fêmea prenhe durante 10 minutos, seguida por tempo igual de reperfusão. O imunossupressor utilizado foi Tacrolimo (Fk, 5 mg/kg/dia v.o.). Ao final obteve-se os seguintes subgrupos: Alo-Tx, Alo-Pci, Alo-Fk, Alo-Pci-Fk, Iso-Tx, Iso-Pci, Iso-Fk e Iso-Pci-Fk. O enxerto foi transplantado no espaço entre o músculo reto-abdominal e pré- peritoneal dos receptores a meio centímetro do apêndice xifóide, à esquerda da linha mediana. Após o sétimo dia de seguimento, o enxerto foi removido, fixado e embebido em parafina para avaliação histomorfológica (desenvolvimento e rejeição) e análise imunohistoquímica (anti-PCNA e anti-caspase-3 clivada). Os dados foram analisados usando ANOVA e testes complementares e foi considerado significante quando p <0.05. Resultados: A avaliação do desenvolvimento do enxerto no grupo de Iso mostrou que o PCI-R reduziu o desenvolvimento comparado com Iso-Tx (5,2±0,4 vs 9,0±0,8), o Fk e sua associação com PCI-R aumentaram o desenvolvimento do enxerto comparado com PCI-R (11,2±0,7 e 10,2±0,8, respectivamente). No grupo Alo, o Fk e/ou sua associação com PCI-R aumentaram o desenvolvimento comparado com Alo-Tx e Alo com PCI-R (6,0±0,8, 9,0±1,2, 0,0±0,0, 0,5±0,3, respectivamente). A expressão de PCNA foi maior no grupo ISO em animais tratados com Fk e PCI-R comparados a outros grupos (12,2±0,8 vs Tx: 8,8±0,9, PCI-R: 8,0±0,4 e Fk: 9,0±0,6). No grupo Alo, a expressão de PCNA não diferiu entre grupos. A rejeição do enxerto foi menor nos grupos tratados com PCI-R (-18%), Fk (- 68%) ou ambos (-61%) comparados com Alo-Tx. A expressão de caspase-3 clivada foi menor no grupo Iso em animais tratados com associação de PCI-R e Fk (6,2 ±0,9 vs Tx: 8,6±0,5; PCI-R: 5,8 ±0,9 e Fk: 6,0 ±0,3). Conclusão: O PCIR mostrou efeito benéfico sobre a lesão de isquemia e reperfusão do enxerto intestinal fetal nos transplantes isogênico e alogênico, aumentando o número de células caliciformes e a proliferação celular. No transplante alogênico, aumentou o desenvolvimento do enxerto, diminuiu o grau de rejeição aguda na ausência de imunossupressão, porém não apresentou efeito sinérgico com o imunossupressor. No transplante isogênico houve diminuição do grau de desenvolvimento do enxerto, porém foi efetivo na redução da apoptose.

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[ES] En este trabajo, hemos tratado de identificar, y poner a punto las técnicas necesarias para la cuantificación de los miRNAs asociados con el control post-transcripcional del receptor de andrógenos (AR) y el receptor de estrógenos (ER) en tumores de mama. Para ello, hemos usado las bases de datos publicadas en Internet. Además, comparamos la cantidad y la calidad del RNA total aislado (miRNA y mRNA) en 11 tumores de mama incluidos en parafina mediante el uso de dos kits comerciales.

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Esta Tesis plantea la pregunta de si el uso de morteros con parafinas microencapsuladas combinado con colectores solares térmicos puede reducir el consumo de energías convencionales, en un sistema tradicional de suelo radiante. Se pretende contribuir al conocimiento acerca del efecto que produce en el edificio, el calor latente acumulado en suelos radiantes, utilizando morteros de cemento Portland con material de cambio de fase (PCM), en conjunto con la energía solar. Para cumplir con este propósito, la investigación se desarrolla considerando diversos aspectos. En primer lugar, se revisa y analiza la documentación disponible en la actualidad, de almacenamiento de energía mediante calor latente en la construcción, y en particular la aplicación de microcápsulas de PCM en morteros y suelos radiantes. También se revisa la documentación relacionada con la aplicación de la energía solar térmica y en suelo radiante. Se analiza la normativa vigente respecto al material, a los colectores solares y al suelo radiante. Se verifica que no hay normativa relacionada con mortero-PCM, debido a esto se aplica en la investigación una adaptación de la existente. La fase experimental desarrollada esta principalmente dirigida a la cuantificación, caracterización y evaluación de las propiedades físicas, mecánicas y térmicas del mortero de cemento Portland con parafinas microencapsuladas. Los resultados obtenidos y su análisis, permiten conocer el comportamiento de este tipo de morteros, con las diferentes variables aplicadas en la investigación. Además, permite disponer de la información necesaria, para crear una metodología para el diseño de morteros con parafina microencapsulada, tanto del punto de vista de su resistencia a la compresión y contenido de PCM, como de su comportamiento térmico como acumulador de calor. Esto se logra procesando la información obtenida y generando modelos matemáticos, para dosificar mezclas, y predecir la acumulación de calor en función de su composición. Se determinan los tipos y cantidades de PCM, y el cemento más adecuado. Se obtienen importantes conclusiones respecto a los aspectos constructivos a considerar en la aplicación de morteros con PCM, en suelo radiante. Se analiza y evalúa la demanda térmica que se puede cubrir con el suelo radiante, utilizando morteros con parafina microencapsulada, a través de la acumulación de energía solar producida por colectores solares, para condiciones climáticas, técnicas y tipologías constructivas específicas. Se determina que cuando los paneles cubren más de 60 % de la demanda por calefacción, se puede almacenar en los morteros con PCM, el excedente generado durante el día. Se puede cubrir la demanda de acumulación de energía con los morteros con PCM, en la mayoría de los casos analizados. Con esto, se determina que el uso de morteros con PCM, aporta a la eficiencia energética de los edificios, disminuyendo el consumo de energías convencionales, reemplazándola por energía solar térmica. En esta investigación, el énfasis está en las propiedades del material mortero de cemento-PCM y en poder generar metodologías que faciliten su uso. Se aborda el uso de la energía solar, para verificar que es posible su acumulación en morteros con PCM aplicados en suelo radiante, posibilitando el reemplazo de energías convencionales. Quedan algunos aspectos de la aplicación de energía solar a suelo radiante con morteros con PCM, que no han sido tratados con la profundidad que requieren, y que resultan interesantes de evaluar en este tipo de aplicaciones constructivas, como entre otros, los relacionados con la cuantificación de los ahorros de energía en las diferentes estaciones del año, de la estabilización de temperaturas internas, su análisis de costo y la optimización de este tipo de sistemas para utilización en verano, los que dan pie para otras Tesis o proyectos de investigación. ABSTRACT This Thesis proposes the question of whether the use of mortars with microencapsulated paraffin combined with solar thermal collectors can reduce conventional energy consumption in a traditional heating floor system. It aims to contribute to knowledge about the effect that it has on the building, the latent heat accumulated in heating floor, using Portland cement mortars with phase change material (PCM), in conjunction with solar energy. To fulfill this purpose, the research develops it considering various aspects. First, it reviews and analyzes the documentation available today, about energy storage by latent heat in the building, and in particular the application of PCM microcapsules in mortars and heating floors. It also reviews the documentation related to the application of solar thermal energy and heating floor. Additionally, it analyzes the current regulations regarding to material, solar collectors and heating floors. It verifies that there aren’t regulations related to PCM mortar, due to this, it applies an adaptation in the investigation. The experimental phase is aimed to the quantification, mainly, characterization and evaluation of physical, mechanical and thermal properties of Portland cement mortar with microencapsulated paraffin. The results and analysis, which allow us to know the behavior of this type of mortars with different variables applied in research. It also allows having the information necessary to create a methodology for designing mortars with microencapsulated paraffin, both from the standpoint of its resistance to compression and PCM content, and its thermal performance as a heat accumulator. This accomplishes by processing the information obtained, and generating mathematical models for dosing mixtures, and predicting heat accumulation depending on their composition. The research determines the kinds and amounts of PCM, and the most suitable cement. Relevant conclusions obtain it regarding constructive aspects to consider in the implementation of PCM mortars in heating floor. Also, it analyzes and evaluates the thermal demand that it can be covered in heating floor using microencapsulated paraffin mortars, through the accumulation of solar energy produced by solar collectors to weather conditions, technical and specific building typologies. It determines that if the panels cover more than 60% of the demand for heating, the surplus generated during the day can be stored in PCM mortars. It meets the demand of energy storage with PCM mortars, in most of the cases analyzed. With this, it determines that the use of PCM mortars contributes to building energy efficiency, reducing consumption of conventional energy, replacing it with solar thermal energy. In this research approaches the use of solar energy to determine that it’s possible to verify its accumulation in PCM mortars applied in heating floor, enabling the replacement of conventional energy. The emphasis is on material properties of PCM mortar and, in order to generate methodologies to facilitate their use. There are some aspects of solar energy application in PCM mortars in heating floor, which have not been discussed with the depth required, and that they are relevant to evaluate in this kind of construction applications, including among others: the applications related to the energy savings quantification in different seasons of the year, the stabilizing internal temperatures, its cost analysis and optimization of these systems for use in summer, which can give ideas for other thesis or research projects.

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According to the last global burden of disease published by the World Health Organization, tumors were the third leading cause of death worldwide in 2004. Among the different types of tumors, colorectal cancer ranks as the fourth most lethal. To date, tumor diagnosis is based mainly on the identification of morphological changes in tissues. Considering that these changes appears after many biochemical reactions, the development of vibrational techniques may contribute to the early detection of tumors, since they are able to detect such reactions. The present study aimed to develop a methodology based on infrared microspectroscopy to characterize colon samples, providing complementary information to the pathologist and facilitating the early diagnosis of tumors. The study groups were composed by human colon samples obtained from paraffin-embedded biopsies. The groups are divided in normal (n=20), inflammation (n=17) and tumor (n=18). Two adjacent slices were acquired from each block. The first one was subjected to chemical dewaxing and H&E staining. The infrared imaging was performed on the second slice, which was not dewaxed or stained. A computational preprocessing methodology was employed to identify the paraffin in the images and to perform spectral baseline correction. Such methodology was adapted to include two types of spectral quality control. Afterwards the preprocessing step, spectra belonging to the same image were analyzed and grouped according to their biochemical similarities. One pathologist associated each obtained group with some histological structure based on the H&E stained slice. Such analysis highlighted the biochemical differences between the three studied groups. Results showed that severe inflammation presents biochemical features similar to the tumors ones, indicating that tumors can develop from inflammatory process. A spectral database was constructed containing the biochemical information identified in the previous step. Spectra obtained from new samples were confronted with the database information, leading to their classification into one of the three groups: normal, inflammation or tumor. Internal and external validation were performed based on the classification sensitivity, specificity and accuracy. Comparison between the classification results and H&E stained sections revealed some discrepancies. Some regions histologically normal were identified as inflammation by the classification algorithm. Similarly, some regions presenting inflammatory lesions in the stained section were classified into the tumor group. Such differences were considered as misclassification, but they may actually evidence that biochemical changes are in course in the analyzed sample. In the latter case, the method developed throughout this thesis would have proved able to identify early stages of inflammatory and tumor lesions. It is necessary to perform additional experiments to elucidate this discrepancy between the classification results and the morphological features. One solution would be the use of immunohistochemistry techniques with specific markers for tumor and inflammation. Another option includes the recovering of the medical records of patients who participated in this study in order to check, in later times to the biopsy collection, whether they actually developed the lesions supposedly detected in this research.

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A proposta busca reduzir a absorção de água dos agregados reciclados de Resíduos de Construção e Demolição (RCD), através do tratamento de sua superfície com hidrofugante, de maneira que estes não aumentem o consumo de água tampouco reduzam a resistência mecânica. Os agregados reciclados de RCD foram caracterizados quanto à granulometria, morfologia, porosidade, ângulo de contato aparente, absorção de água, análise de imagem e rugosidade superficial. Em seguida, os mesmos foram tratados superficialmente com dois tipos de hidrofugante: solução de silano e parafina. Todos os tratamentos permitiram reduzir a absorção de água dos agregados reciclados de RCD. O tratamento por imersão foi aquele que permitiu obter os melhores resultados e a menor variabilidade entre as técnicas. Os tratamentos hidrofugam a superfície, apesar da parafina apresentar maior molhabilidade. O tratamento com parafina apresentou, em termos de absorção de água, resultados inferiores e menos variáveis que o silano. Os parâmetros de rugosidade constataram que, ambos os materiais perdem seu perfil topográfico original quando tratados com parafina. Os diferentes agregados reciclados com cada hidrofugante foram aplicados em materiais cimentícios analisados no estado fresco e no estado endurecido. Os tratamentos reduziram a absorção e o consumo de água de mistura, porém afetaram negativamente as propriedades mecânicas, devido nova interface gerada (no caso específica de parafina) e falta de molhabilidade nas superfícies.

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En este trabajo se analizarán las características estructurales, cuantitativas y el proceso de muerte celular por apoptosis en el ovario de C. maculosa y C.picui con el objetivo de aportar conocimientos básicos a la biología reproductiva de estas aves. Cincuenta hembras adultas de cada especie se capturarán en el Dpto. Río Primero (Pcia. de Cba), R. Argentina, durante el ciclo reproductivo 2011-2012. Las muestras de ovarios se fijaran en Formalina Neutra pH 7.0, procesarán con la técnica de inclusión en parafina y colorearan con Hematoxilina /Eosina y Reacción Nuclear de Feulgen. Cinco muestras serán utilizadas para la determinación de muerte celular por apoptosis con la técnica de TUNEL. Se estudiarán las características morfohistológicas del ovario de C.maculosa y C. picui e identificarán, categorizarán y cuantificarán los folículos atrésicos no bursting (folículos atrésicos previtelogénicos y vcitelogénicos pequeños que conservan la integridad de la pared folicular) y bursting (folículos vitelogénicos mayores de 2 mm que liberar el contenido folicular por ruptura de la pared folicular) durante el ciclo reproductivo anual. Mediante la marcación de ADN fragmentado, se revelará la muerte celular por apoptosis en las células granulosas de los folículos atrésicos. Se compararán las semejanzas y diferencias estructurales y cuantitativas y el proceso de muerte celular en los folículos regresivos entre las dos especies. Los resultados de este trabajo representarán un importante aporte al conocimiento de la atresia folicular como así también a la muerte celular, un proceso estrechamente asociado a la misma, aún poco estudiado en el ovario de las aves.

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Compatibility testing between a drilling fluid and a cement slurry is one of the steps before an operation of cementing oil wells. This test allows us to evaluate the main effects that contamination of these two fluids may cause the technological properties of a cement paste. The interactions between cement paste and drilling fluid, because its different chemical compositions, may affect the cement hydration reactions, damaging the cementing operation. Thus, we carried out the study of the compatibility of non-aqueous drilling fluid and a cement slurry additives. The preparation procedures of the non-aqueous drilling fluid, the cement paste and completion of compatibility testing were performed as set out by the oil industry standards. In the compatibility test is evaluated rheological properties, thickening time, stability and compressive strength of cement pastes. We also conducted analyzes of scanning electron microscopy and X-ray diffraction of the mixture obtained by the compatibility test to determine the microstructural changes in cement pastes. The compatibility test showed no visual changes in the properties of the cement paste, as phase separation. However, after the addition of nonaqueous drilling fluid to cement slurry there was an increased amount of plastic viscosity, the yield point and gel strength. Among the major causative factors can include: chemical reaction of the components present in the non-aqueous drilling fluid as the primary emulsifier, wetting agent and paraffin oil, with the chemical constituents of the cement. There was a reduction in the compressive strength of the cement paste after mixing with this drilling fluid. Thickening test showed that the oil wetting agent and high salinity of the non-aqueous fluid have accelerating action of the handle of the cement paste time. The stability of the cement paste is impaired to the extent that there is increased contamination of the cement slurry with the nonaqueous fluid. The X-ray diffraction identified the formation of portlandite and calcium silicate in contaminated samples. The scanning electron microscopy confirmed the development of the identified structures in the X-ray diffraction and also found the presence of wells in the cured cement paste. The latter, formed by the emulsion stability of the drilling fluid in the cement paste, corroborate the reduction of mechanical strength. The oil wetting agent component of the non-aqueous drilling fluid, the modified cement hydration processes, mainly affecting the setting time.

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In this study we evaluated the capacity removal of PAHs in an oily solution between the bentonite hydrofobized with linseed oil and paraffin with natural bentonite. Analyses of natural bentonite and hydrofobized were made by the characterization techniques: (1) Thermogravimetric Analysis (TGA), which aimed to evaluate the thermal events due to mass loss, both associated with the exit of moisture and decomposition of clay as due to hidrofobizante loss agent. (2) Analysis of X-ray diffraction (XRD) in order to determine the mineralogical phases that make up the structure of clay and (3) Spectrophotometry in the infrared region used to characterize the functional groups of both the matrix mineral (bentonite) and the hidrofobizantes agents (linseed oil and paraffin). We used a factorial design 24 with the following factors; hidrofobizante, percent hidrofobizante, adsorption time and volume of the oily solution. Analyzing the factorial design 24 was seen that none of the factors apparently was more important than the others and, as all responses showed significant values in relation to the ability of oil removal was not possible to evaluate a difference in the degree of efficiency the two hidrofobizantes. For the new study compared the efficiency of the modified clay, with each hidrofobizante separately in relation to their natural form. As such, there are four new factorial designs 23 using natural bentonite as a differentiating factor. The factors used were bentonite (with and without hydrophobization), exposure time of the adsorbent material to the oily solution and volume of an oily solution, trying to interpret how these factors could influence the process of purifying water contaminated with PAHs. Was employed as a technique for obtaining responses to fluorescence spectroscopy, as already known from literature that PAHs, for presenting combined chains due to condensation of the aromatic rings fluoresce quite similar when excited in the ultraviolet region and as an auxiliary technique to gas chromatography / mass spectrometry (GC-MS) used for the analysis of PAHs in order to complement the study of fluorescence spectroscopy, since the spectroscopic method only allows you an idea of total number of fluorescent species contained in the oil soluble. The result shows an excellent adsorption of PAHs and other fluorescent species assigned to the main effect of the first factor, hydrophobization for the first planning 23 BNTL 5%, for 93% the sixth stop in the second test (+-+),factorial design 23 BNTL 10%, the fourth test (++-) with 94.5% the third factorial design 23 BNTP 5%, the second test (+--) with 91% and the fourth and final planning 23 BNTP 10%, the last test ( + + +) with 88%. Compared with adsorption of bentonite in its natural form. This work also shows the maximum adsorption of each hidrofobizante

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The peripheral giant cell lesion ( PG CL ) and the central giant cell lesion ( CGC L) are lesions histologically similar affecting the head and neck region . The study aimed to analyze the immunohistochemical expression of markers GLUT - 1 , GLUT - 3 and M - CSF in a series of cases of PGCL and CGCL , in trying to understand the different biological behavior of these pathologies . The sample consisted of 20 tissue specimens of PGCL 20 central lesion of not aggressive giant cell ( CLNAGC) and 20 central lesi on of aggressive giant cell ( CLAGC), coming from the Pathology Unit of Oral Pathology of the Department of Dentistry of UFRN . W as performed the s emi - quantitative and qualitative analysis of immunohistochemical expression of the markers in giant cells and m ononuclear cells . In relation to the GLUT - 1, it was found a statistically significant difference (p < 0.05) in the number of mononuclear cells immunomarked between the PGCL and the CLNAGC and between the PGCL and CLAGC . Regarding the intensity of staining w as also observed a statistically significant difference both at the mononuclear cells as in giant cells between PL and CLNAGC and between PGCL and CLAGC , at the giant cells there was also a statistically significant difference between the CLNAGC and CLAGC . In relation to GLUT - 3 , was found a statistically significant difference between PGCL and CLAGC and between CLAGC and CLNAGC in amount of mononuclear cells immunomarked . Regarding the intensity of labeling for such protein was found a statistically signifi cant difference at the giant cells between PL and CLAGC . To the M - CSF was observed only a statistically significant difference in the intensity of labeling at the mononuclear cells between PGCL and CLNAGC and between PGCL and CLAGC . Based on these results, we can conclude the participation of GLUT - 1, GLUT - 3 and M - CSF in the pathogenesis of the lesions studied. The bigger immunostaining of these proteins in mononuclear cells show that these cells perform a higher metabolic activity and osteoclastogenic, espe cially in CLAGC . It was found that the mononuclear cells were more related to the pathogenesis of the studied lesions than properly the giant s cell s.

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The oil industry is one of the activities that generates more waste to the environment. The drill cuttings is a waste generated in large quantities in the drilling process and that may cause environmental damage such as soil contamination and consequently the contamination of groundwater if disposed of without prior treatment. Arises the need to develop scientific activities and research ways to adapt these wastes the current environmental standards. In the case of solid wastes, the NBR 10004: 2004 of the Brazilian Association of Technical Standards (ABNT) classifies them into class I waste (hazardous) and class II (not dangerous), which determines which wastes may or may not be discarded in the environment without causing environmental impact. This study presents a novel alternative for treating drill cuttings, where this waste was classified as class I (Abreu & Souza, 2005), mainly by removing the n-paraffin present in it, since this arises when using drilling fluids base oil. Using microemulsion systems promotes the removal of this contaminant drill cuttings samples from wells located in Alto do Rodrigues - RN. Initially, we determined the concentration of paraffin using infrared method in samples were extracted with ultrasound, we obtained a paraffin concentration in the range from 36.59 to 43.52 g of paraffin per kilogram of cuttings. Used two microemulsion systems containing two nonionic surfactants from different classes, one is an alcohol ethoxylated (UNTL-90) and the other an nonylphenol ethoxylated (RNX 110). The results indicated that the system UNTL-90 surfactant has better efficiency than the system with RNX 110. The study of the influence of contact time at the extraction showed that for times greater than 25 minutes has a tendency to increase the percentage extraction with increasing contact time. It was also observed that the extraction is fast because at 1 minute contact has 22.7% extraction. The reuse of the microemulsion system without removing the paraffin extracted in previous steps, showed reduction of 29.32 in percentage of extraction by comparing the first and third extraction, but by comparing the first and second extractions reduction is 8.5 in percentage extraction, so the systems reuse optimization can be an option for economically viable removing paraffin from cuttings. The extraction with shaking is more effective in the treatment of cuttings, reaching the extraction percentage of 87.04%, that is, obtaining a drill cuttings with 0.551% paraffin. Using the percentage of paraffin employed in non-aqueous drilling fluids and fluid maximum limit on cuttings for disposal established by the Environmental Protection Agency of the United States (US EPA), one arrives at the conclusion that the level of paraffin on gravel cannot exceed 3.93%. Conclude that the amount of paraffin in the treated cuttings with the microemulsion system with shaking is below the established by US EPA, showing that the system used was efficient in removing the paraffin from the drill cuttings.

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This work describes the synthesis and study of the application of a new surfactant (Triester Lipophilic – TEL) obtained by citric acid with octanol. It is reaction was followed by thin layer chromatography (TLC) and after purification the product was characterized by proton and 13 – carbon nuclear magnetic resonance spectroscopy ( H and 13C NMR), thermogravimetric analysis (TGA) and surface tension analysis of oil-in-water emulsions. The TEL performance as surfactant in ester, n-paraffin and biodiesel based drilling fluids on the 70/30 and 60/40 water- oil rations (WOR) was evaluated by comparative tests of two commercial products used in the fields. These drilling fluids were aged in roller oven at 200 0 F during 16 h. The rheological and electric stability measurements were carried out at 135 ºF, the phase separation was evaluated after seven days at rest and the filtrate volume of drilling fluids was determined at high temperature and high pressure. The rheological behavior of the drilling fluids was evaluated by the flow curves. The results showed that the drilling fluids studied here presented Binghamian behavior as well as the used in the oil fields. The laboratory tests showed that the TEL reduced the filtrate volume and promoted the enhance of the thermal and mechanical stabilities.

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Except the non-melanoma skin tumors, colorectal cancer is the second most common in the Southeastern Region of Brazil, the third most common in the Southern and Central Regions. It is also the forth most common in the Northern Region and it is the fifth one in the Northeastern. To assess pathological and clinical variables of colorectal Cancer is crucial to know the possible conclusions for the survival of patients and point out the characteristics in the progress of tumor, such as the profile of tumor invasion and its angiogenesis. This work focuses on analyzing clinically and pathologically some settings in colorectal cancer patients (CRC) in the city of Natal and its countryside through those variables as parameters of prognosis and determine the level of protein expression, for instance: E-cadherin (E-cad), beta- -catenin (β-cat), galectin-3 (gal-3), matrix metalloproteinases (MMP) 2 and 9 and vascular-endothelial growth factor alpha (α VEGF) in the tumor tissues. A retrospective study was done in colorectal cancer cases in the regions of Rio Grande do Norte state from 1995 to 2005, specifically in Natal city/RN/Brazil. The pathological and clinical variables, such as: age, gender, ethnicity, lifestyle, family history, the location of the primary tumor, level of differentiation, TDM staging, modified Dukes’, treatment and survival were analyzed. The pathological and clinical data were collected from medical records through a specific form and were filed on Excel. A total of 534 patients were selected from the Pathology Department file in this institution, however, 176 patients were excluded. 358 patients were included for Epidemiological analysis and its clinical and pathological correlations were selected. 180 patients were also selected for histological and immunohistochemical studies. The tumor progression of these selected proteins mentioned before were analyzed. The Paraffin blocks of these samples were treated by Microarray Tissue technique and its blades subjected to immunohistochemistry to test the intensity of these proteins in tumor tissues. The results of this analysis were correlated with clinicopathologic variables of patients. Statistical analysis using the chi-frame Pearson test and analysis of midlife by Kaplan-Meier curve was also utilized. P values < 0.05 were considered statistically significant. The average age of our sample was 58.8 years and 51.7 % were female. Alcohol consumption has increased by 1.71 time the risk of death by CCR (p = 0.034) and tobacco consumption increased 2.7 times the chance of developing tumors of high TNM stage (p = 0.001). Cancer patients had a family history of 3,833 times the chance of developing the CCR (p = 0.002). The expression of MMP-2 showed a significant association with tumors of high TNM stage (p <0.046) and mortality (p = 0.041). The α VEGF expression had statistically significant correlation with high TNM stage (p <0.009), degree of cell indifferentiation (p <0.025) and mortality (p <0.035). Expressions of E-cadherin and beta-catetina demonstrated tumor linked to high TNM stage (p = 0.0001) and Dukes› modified (p = 0.05), lesions in the rectum (p = 0.03 and p = 0.007, respectively), smoking (p = 0.05) and indifferentiation (p = 0.001). The expression of Gal-3 showed statistical significance with high TNM stage of patients (p = 0.01), smokers (p = 0.01), alcohol drinking (p = 0.03), indifferentiation (p = 0.0001) and mortality (p = 0.0001). Based on the results, therefore, we could realize that lifestyle and family history had correlation in the CCR prognosis, as well as MMP-2 expression, MMP-9, VEGF alpha, E-cadherin, Beta-catenin and Galectin-3 were important prognostic markers in tumor progression in colorectal cancer.

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Introduction: Apurinic/Apyrimidinic Endonuclease 1 (APE-1) is an essential protein for DNA base excision repair (BER) pathway and regulation of redox activities. The ability of malignant cells to recognize and repair DNA damage is an important mechanism for tumor survival, and recent studies suggest that APE-1 overexpression is related to poor prognosis in some tumors. Purpose: To analyze the immunoreactivity of APE-1 in Pleomorphic Adenomas (PA) and Carcinomas Ex Pleomorphic Adenomas (CaExPA) of salivary glands. Materials and Methods: A total of 49 tumors fixed in formalin and embedded in paraffin (33 PA and 16 CaExPA) underwent immunohistochemical study by the immunoperoxidase technique. APE-1 immunoreactivity was evaluated quantitatively by the percentage of immunopositive cells. For statistical analysis a significance level of 5% (p≤ 0.05) was adopted. Results: All cases of PA and CaExPA (n=49) were positive for APE-1, however, there was a higher expression in CaExPA, with statistically significant difference (p<0.001). There was no association between APE-1 expression and tumors of major or minor salivary gland, however, not encapsulated PA (median expression = 54.2%) showed higher expression when compared to encapsulated tumors (p=0.02). APE-1 overexpression was found mainly in cases of CaExAP with lymph node metastasis (median expression = 90.3% - p=0.002) and invasive pattern (median expression = 89.9% - p=0.003), when compared to cases without metastasis and intracapsular pattern. Conclusion: This study suggests that APE-1 is deregulated in the studied tumors. The increased expression of APE-1 is associated with the absence of complete capsule in PA and it is associated with more aggressive behavior in CaExPA.

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Introduction: Apurinic/Apyrimidinic Endonuclease 1 (APE-1) is an essential protein for DNA base excision repair (BER) pathway and regulation of redox activities. The ability of malignant cells to recognize and repair DNA damage is an important mechanism for tumor survival, and recent studies suggest that APE-1 overexpression is related to poor prognosis in some tumors. Purpose: To analyze the immunoreactivity of APE-1 in Pleomorphic Adenomas (PA) and Carcinomas Ex Pleomorphic Adenomas (CaExPA) of salivary glands. Materials and Methods: A total of 49 tumors fixed in formalin and embedded in paraffin (33 PA and 16 CaExPA) underwent immunohistochemical study by the immunoperoxidase technique. APE-1 immunoreactivity was evaluated quantitatively by the percentage of immunopositive cells. For statistical analysis a significance level of 5% (p≤ 0.05) was adopted. Results: All cases of PA and CaExPA (n=49) were positive for APE-1, however, there was a higher expression in CaExPA, with statistically significant difference (p<0.001). There was no association between APE-1 expression and tumors of major or minor salivary gland, however, not encapsulated PA (median expression = 54.2%) showed higher expression when compared to encapsulated tumors (p=0.02). APE-1 overexpression was found mainly in cases of CaExAP with lymph node metastasis (median expression = 90.3% - p=0.002) and invasive pattern (median expression = 89.9% - p=0.003), when compared to cases without metastasis and intracapsular pattern. Conclusion: This study suggests that APE-1 is deregulated in the studied tumors. The increased expression of APE-1 is associated with the absence of complete capsule in PA and it is associated with more aggressive behavior in CaExPA.

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The chronic state of hyperglycemia due to diabetes mellitus affects multiples organs impairing life quality. In bone, diabetes alters strength and mineral density and also suppresses the osteoblast activity, leading to an unbalanced bone healing process. Hyperbaric oxygen therapy (HBO) is suggested as an adjuvant treatment to accelerate bone repair. This study evaluated the effects of HBO in the number of mast cells and in new bone formation at the initial stage of bone repair in normoglycemic and diabetic rats. It was hypothesized that HBO treatment may improve bone repair in diabetic bone. The rats were equally divided in four groups: Control (C); Control + HBO (CH); Diabetes (D) and Diabetes + HBO (DH). Diabetes was induced by streptozotocin (65mg/kg) and femoral bone defects were created thirty days after diabetes induction in all groups. HBO initiated immediately after surgery procedure and was performed daily, for 7 days, in the CH e DH groups. Seven days after surgery, all animals were euthanized. The femur diaphyses were removed, fixated, decalcified and processed for paraffin embedding. The semi-serial histological sections obtained were stained with Hematoxylin-Eosin (HE), Mallory Trichrome and Toluidine Blue. The qualitative analysis was conducted in the histology slides stained with HE, where it was evaluated the morphological aspects of bone repair in the lesion area, observing the presence of clot, inflammatory cells, granulation tissue, type of bone tissue, morphology of bone cells, and thickness and organization of bone trabeculae. In the slides stained with Mallory Trichrome and Toluidine Blue were evaluated the percentage of new bone formation and number of mast cells, respectively. The qualitative analysis showed that the CH group presented a more advanced stage of bone repair compared to the C group, showing thicker trabeculae and greater bone filling of the lesion area. In D and DH group, the lesion area was partially filled with new bone formation tissue and presented thinner trabeculae and fewer areas associated to osteoclasts compared to control group. The histomorphometric analysis showed a significant improvement in new bone formation (p<0.001) comparing CH (38.08 ± 4.05) and C (32.05 ± 5.51); C and D (24.62 ± 2.28 and CH and DH (27.14 ± 4.21) groups. In the normoglycemic rats there was a significant increasing in the number of mast cells (p<0.05) comparing C (8.06 ± 5.15) and CH (21.06 ± 4.91) groups. In conclusion, this study showed that diabetes impaired bone repair and HBO was only able to increase new bone formation and the number of mast cells in the normoglycemic animals.