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The degradation of mesoporous silica nanoparticles (MSNs) in the biological milieu due to silica hydrolysis plays a fundamental role for the delivery of encapsulated drugs and therapeutics. However, little is known on the evolution of the pore arrangement in the MSNs in biologically relevant conditions. Small Angle X-ray scattering (SAXS) studies were performed on unmodified and PEGylated MSNs with a MCM-48 pore structure and average sizes of 140 nm, exposed to simulated body fluid solution (SBF) at pH 7.4 for different time intervals from 30 min to 24 h. Experiments were performed with silica concentrations below, at and over 0.14 mg/mL, the saturation concentration of silica in water at physiological temperature. At silica concentrations of 1 mg/mL (oversaturation), unmodified MSNs show variation in interpore distances over 6 h exposure to SBF, remaining constant thereafter. A decrease in radius of gyration is observed over the same time. Mesoporosity and radius of gyration of unmodified MSNs remain then unchanged up to 24 h. PEGylated MSNs at 1 mg/mL concentration show a broader diffraction peak but no change in the position of the peak is observed following 24 h exposure to SBF. PEGylated MSNs at 0.01 mg/mL show no diffraction peaks already after 30 min exposure to SBF, while at 0.14 mg/mL a small diffraction peak is present after 30 min exposure but disappears after 1 h.

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Total resistance (rt) to evaporative water loss (EWL) in amphibians is given by the sum of the boundary layer (rb) and the skin resistance (rs). Thus, rs can be determined if the rb component is defined (rs=rt-rb). The use of agar models has become the standard technique to estimate rb under the assumption that the agar surface imposes no barrier to evaporation (rs=0). We evaluated this assumption by determining EWL rates and rb values from exposed surfaces of free water, a physiological solution mimicking the osmotic properties of a generalized amphibian, and agar gels prepared at various concentrations using either water or physiological solution as diluent. Water evaporation was affected by both the presence of solutes and agar concentration. Models prepared with agar at 5% concentration in water provided the most practical and appropriate proxy for the estimation of rb.

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Poly(lactic-co-glycolic acid) (PLGA) has been used in the field of tissue engineering as a scaffold due to its good biocompatibility, biodegradability and mechanical strength. With the aim to explore the degradability of PLGA electrospun nonwoven structures for oral mucosa tissue engineering applications, non-irradiated and gamma irradiated nonwovens were immersed in three different solutions, in which simulated body fluid (SBF) and artificial saliva are important for future oral mucosa tissue engineering. The nonwovens were immersed for 7, 15 and 30 days in SBF, culture media (DMEM) and artificial saliva at 37 °C. Before immersion in the solutions, the dosage of 15 kGy was applied for sterilization in one assay and compared with non-irradiated samples at the same timepoints. Samples were characterized using different techniques such as scanning electron microscopy (SEM), differential scanning calorimetric (DSC) and gel permeation chromatography (GPC) to evaluate the nonwoven degradation and Fourier-transform infrared spectroscopy (FTIR) to evaluate the chain scissions. Our results showed that PLGA nonwovens were constituted by semicrystalline fibers with moderate degradation properties up to thirty days. The non-irradiated samples exhibited slower kinetics of degradation than irradiated nonwovens. For immersion times longer than 7 days in the three different solutions, the mean diameter of irradiated fibers stayed in the same range, but significantly different from the control sample. On non-irradiated samples, the degradation kinetics was slower and the plateau in the diameter value was only attained after 30 days of immersion in the fluids. Plasticization (fluid absorption into the fiber structure) occurred in the bulk material, as confirmed by a decrease in Tg observed by DSC analyses of non-irradiated and irradiated nonwovens, in comparison with the respective controls. In addition, artificial saliva showed a higher capacity of influencing PLGA crystallization than SBF and DMEM. FTIR analyses showed typical PLGA chemical functional groups changes. These results will be important for future application of those PLGA electrospun nonwovens for oral mucosa regeneration.

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OBJECTIVES: In patients with heart failure, fluid alteration and low muscle strength frequently coexist because of their reduced physical activity and sedentary behavior; however, few studies have evaluated the effects of this coexistence on the prognosis of these patients. The aim of this study was to examine the independent association between fluid alteration and the low handgrip strength (HGS) index with mortality in patients with chronic heart failure. METHODS: This observational study included 546 (53.3% male) stable outpatients with heart failure. The presence of an abnormal fluid distribution was determined with a bioelectrical impedance ratio (200/5 kHz) ≥0.85. Handgrip strength (HGS) was measured with a hand dynamometer, and the HGS index was calculated by dividing the HGS (kg) by the squared height (meters). A low HGS index was defined if men had <10.1 and women <7.95 kg/m2. The primary outcome was all-cause mortality. RESULTS: The mean age of the study population was 60.75 ± 17 y, and 30% were classified with a low HGS index, 9.5% with an abnormal fluid distribution, and 29% with both. During the 36 mo of follow-up, 16.5% of the participants reached the endpoint. In men but not in women, coexistence of a low HGS index and abnormal fluid distribution were independently associated with all-cause mortality with a hazard ratio of 2.8 (95% confidence interval, 1.25-6.4; P = 0.01). CONCLUSIONS: In men with heart failure, co-existence of a low HGS index and abnormal fluid distribution was independently associated with all-cause mortality.

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A simple, inexpensive, highly sensitive, selective, and novel electrochemical method was developed for determination of the Bisphenol A in samples of tap water, blood serum, and urine using a bentonite-modified carbon paste electrode. The graphite, bentonite and the working electrodes (without and chemically modified) were characterized by scanning electron microscopy, infrared absorption spectroscopy, and X-ray diffraction. The electrodes were electrochemically characterized using cyclic voltammetry, square wave voltammetry, and electrochemical impedance spectroscopy. The studied electrochemical variables were: electrode area, standard heterogeneous rate constant, charge transfer coefficient and double-layer capacitance. The bentonite as a sensor modifier had a strong influence on these variables. For the development of the methodology to quantify Bisphenol A, the instrumental parameters (frequency, amplitude, and step potential) and experimental parameters (pH, bentonite quantity) were optimized. The analytical curve to Bisphenol showed a linear response of the oxidation peak current intensity vs. the concentration in the range of 6.8 × 10-10 to 1.5 × 10-8 mol mL-1, with a limit of detection (LOD) of 2.11 × 10-11 mol mL-1 and limit of quantification (LOQ) of 7.04 × 10-11 mol mL-1. Recovery experiments were performed by adding known amounts of Bisphenol A in tap water, blood serum, and urine samples. Recovery rates using the standard addition method were in the range of 97.8-101.8%. The results demonstrated the method feasibility for quantifying Bisphenol A in these samples.

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The objective of this study was to determine the frequency of different categories of specific and general classification in canine cavitary effusions (CE), as well as their association with the underlying etiologies. The laboratorial and clinical data from 304 cases of canine CE were retrospectively assessed. In 32.9% (100 cases), at least one of the specific classification categories was established, with a subtotal predominance of neoplasia (42%), bacterial serositis (24%) and hemorrhage (16%). Neoplasia was confirmed by effusion cytology in 57.5% of the cases with histopathological confirmation. From the cases in which the specific classification was not obtained, 35.8% were classified as modified transudate, 30.4% as pure transudate, 21.1% % as exudate and 12.7% was not included in any general category. The most common causes of effusion among these cases were hypoproteinemia and/or hipoalbuminemia (HPHA) (25.8%), hepatopathy (22.5%), cardiac insufficiency (15.5%) and cytologically undetected cases of neoplasia (12.4%). In conclusion, HPHA, hepatopathy and neoplasia represents important etiologies for canine CE development. Classification of effusions, solely based on [TP] and TNCC, might be an inaccurate diagnostic tool of effusions. New laboratorial classification methods for canine CE should be researched.(AU)

O objetivo deste estudo foi determinar a frequência de diferentes categorias de classificação específica e geral em efusões cavitárias (EC) caninas, bem como sua associação com as etiologias subjacentes. Os dados laboratoriais e clínicos de 304 casos de EC canina foram avaliados retrospectivamente. Em 32,9% (100 casos), pelo menos uma das categorias específicas de classificação foi estabelecida, com predomínio subtotal de neoplasia (42%), serosite bacteriana (24%) e hemorragia (16%). A neoplasia foi confirmada pela citologia da efusão em 57,5% dos casos com confirmação histopatológica. Dos casos em que a classificação específica não foi obtida (204 casos), 35,8% foram classificados como transudato modificado, 30,4% como transudato puro, 21,1% como exsudato e 12,7% não foram incluídos em nenhuma categoria geral. As causas mais comuns de efusão nestes casos foram hipoproteinemia e/ou hipoalbuminemia (HPHA) (25,8%), hepatopatia (22,5%), insuficiência cardíaca (15,5%) e casos de neoplasia citologicamente não detectados (12,4%). Em conclusão, HPHA, hepatopatia e neoplasia representam importantes etiologias para o desenvolvimento da EC canina. A classificação geral de efusões, baseada exclusivamente em proteína e celularidade, pode ser uma ferramenta diagnóstica imprecisa. Novos métodos de classificação laboratorial para ECs caninas devem ser pesquisados.(AU)

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The objective of this study was to determine the frequency of different categories of specific and general classification in canine cavitary effusions (CE), as well as their association with the underlying etiologies. The laboratorial and clinical data from 304 cases of canine CE were retrospectively assessed. In 32.9% (100 cases), at least one of the specific classification categories was established, with a subtotal predominance of neoplasia (42%), bacterial serositis (24%) and hemorrhage (16%). Neoplasia was confirmed by effusion cytology in 57.5% of the cases with histopathological confirmation. From the cases in which the specific classification was not obtained, 35.8% were classified as modified transudate, 30.4% as pure transudate, 21.1% % as exudate and 12.7% was not included in any general category. The most common causes of effusion among these cases were hypoproteinemia and/or hipoalbuminemia (HPHA) (25.8%), hepatopathy (22.5%), cardiac insufficiency (15.5%) and cytologically undetected cases of neoplasia (12.4%). In conclusion, HPHA, hepatopathy and neoplasia represents important etiologies for canine CE development. Classification of effusions, solely based on [TP] and TNCC, might be an inaccurate diagnostic tool of effusions. New laboratorial classification methods for canine CE should be researched.(AU)

O objetivo deste estudo foi determinar a frequência de diferentes categorias de classificação específica e geral em efusões cavitárias (EC) caninas, bem como sua associação com as etiologias subjacentes. Os dados laboratoriais e clínicos de 304 casos de EC canina foram avaliados retrospectivamente. Em 32,9% (100 casos), pelo menos uma das categorias específicas de classificação foi estabelecida, com predomínio subtotal de neoplasia (42%), serosite bacteriana (24%) e hemorragia (16%). A neoplasia foi confirmada pela citologia da efusão em 57,5% dos casos com confirmação histopatológica. Dos casos em que a classificação específica não foi obtida (204 casos), 35,8% foram classificados como transudato modificado, 30,4% como transudato puro, 21,1% como exsudato e 12,7% não foram incluídos em nenhuma categoria geral. As causas mais comuns de efusão nestes casos foram hipoproteinemia e/ou hipoalbuminemia (HPHA) (25,8%), hepatopatia (22,5%), insuficiência cardíaca (15,5%) e casos de neoplasia citologicamente não detectados (12,4%). Em conclusão, HPHA, hepatopatia e neoplasia representam importantes etiologias para o desenvolvimento da EC canina. A classificação geral de efusões, baseada exclusivamente em proteína e celularidade, pode ser uma ferramenta diagnóstica imprecisa. Novos métodos de classificação laboratorial para ECs caninas devem ser pesquisados.(AU)

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The use of pesticides in agricultural activities has increased significantly during the last decades. Several studies have reported the health damage that results from exposure to pesticides. In Mexico, hundreds of communities depend economically on agricultural activities. The participation of minors in this type of activity and their exposure to pesticides represents a potential public health problem. A cross-sectional study was conducted, in which urine samples (first-morning urine) were taken from children under 15 years of age in both communities. A total of 281 urine samples obtained in both communities were processed for the determination of pesticides with high-performance liquid chromatography together with tandem mass spectrometry. In 100% of the samples, at least two pesticides of the 17 reported in the total samples were detected. The presence of malathion, metoxuron, and glyphosate was remarkable in more than 70% of the cases. Substantial differences were detected regarding the other compounds. It is necessary to carry out long-term studies to determine the damage to health resulting from this constant exposure and to inform the health authorities about the problem in order to implement preventive measures.

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The purpose of this work is to evaluate single and double-cell membraneless microfluidic fuel cells (MMFCs) that operate in the presence of simulated body fluids SBF, human serum and blood enriched with ethanol as fuels. The study was performed using the alcohol dehydrogenase enzyme immobilised by covalent binding through an array composed of carbon Toray paper as support and a layer of poly(methylene blue)/tetrabutylammonium bromide/Nafion and glutaraldehyde (3D bioanode electrode). The single MMFC was tested in a hybrid microfluidic fuel cell using Pt/C as the cathode. A cell voltage of 1.035V and power density of 3.154mWcm-2 were observed, which is the highest performance reported to date. The stability and durability were tested through chronoamperometry and polarisation/performance curves obtained at different days, which demonstrated a slow decrease in the power density on day 10 (14%) and day 20 (26%). Additionally, the cell was tested for ethanol oxidation in simulated body fluid (SBF) with ionic composition similar to human blood plasma. Those tests resulted in 0.93V of cell voltage and a power density close to 1.237mWcm-2. The double cell MMFC (Stack) was tested using serum and human blood enriched with ethanol. The stack operated with blood in a serial connection showed an excellent cell performance (0.716mWcm-2), demonstrating the feasibility of employing human blood as energy source.

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Determining the type and origin of body fluids in a forensic investigation can provide important assistance in reconstructing crime scenes. A set of epigenetic markers, ZC3H12D, BCAS4 and cg06379435, have been developed to produce unique and specific patterns of DNA methylation that can be used to identify semen, saliva, and blood, respectively. To ensure the efficacy of these markers, developmental validation studies were performed to determine the conditions and limitations of this new tool for forensic analysis. DNA was extracted from human samples and bisulfite modified using commercial bisulfite modification kits. Specific primers were used to amplify the region of interest and the methylation profile of the CpG sites were determined by pyrosequencing. The percent methylation values at each CpG site were determined in multiple samples and averaged for each tissue type. The versatility of these new markers is presented by showing the results of validation studies on sensitivity, human specificity, stability and mixture resolution. When testing the markers using different organisms, we did obtain positive results for certain non-human primate samples, however, all other tested species were negative. The lowest concentration consistently detected varied from 0.1 to 10ng, depending on the locus, indicating the importance of primer design and sequence in the assay. The method also proved to be effective when inhibitors were present in the samples or when samples were degraded by heat. Simulated case- samples were also tested. In the case of mixtures of different cell types, the overall methylation values varied in a consistent and predictable manner when multiple cell types were present in the same sample. Overall, the validation studies demonstrate the robustness and effectiveness of this new tool for body fluid identification.

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Natural rubber latex (NRL) is a flexible biomembrane that possesses angiogenic properties and has recently been used for guided bone regeneration, enhancing healing without fibrous tissue, allergies or rejection. Calcium phosphate (Ca/P) ceramics have chemical, biological, and mechanical properties similar to mineral phase of bone, and ability to bond to the host tissue, although it can disperse from where it is applied. Therefore, to create a composite that could enhance the properties of both materials, NRL biomembranes were coated with Ca/P. NRL biomembranes were soaked in 1.5 times concentrated SBF solution for seven days, avoiding the use of high temperatures. SEM showed that Ca/P has been coated in NRL biomembrane, XRD showed low crystallinity and FTIR showed that is the carbonated type B. Furthermore, hemolysis of erythrocytes, quantified spectrophotometrically using materials (Ca/P, NRL, and NRL + Ca/P) showed no hemolytic effects up to 0.125 mg/mL (compounds and mixtures), indicating no detectable disturbance of the red blood cell membranes. The results show that the biomimetic is an appropriate method to coat NRL with Ca/P without using high temperatures, aiming a new biomembrane to improve guided bone regeneration.

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Estudio prospectivo diseñado con el fin de evaluar a los trabajadores de salud del Hospital Universitario de Caracas que notificaran exposición a fluidos corporales al Sistema de Vigilancia de Virus de Inmunodeficiencia Humana y Hepatitis Viral, desde los años 1991 hasta 1999. Las variables estudiadas fueron: fecha y sitio del accidente, categoría del personal, edad, género, fluido involucrado, tipo de exposición, instrumento utilizado, serología basal para Virus de Inmunodeficiencia Humana y hepatitis viral del paciente índice y del TS, tipo de profilaxis antirretroviral, efectos adversos y seroconversión al Virus de Inmunodeficiencia Humana. Se utilizó el método descriptivo serie de casos los cuales fueron analizados por Epi-info. Versión 5. Durante el período de estudio fueron evaluados 242 trabajadores de la salud con exposición a fluidos corporales, 65% accidentes fueron notificados los dos últimos años. Ciento sesenta y tres femeninos y 79 masculinos, edad promedio 43 años (rango de 21-65 años). Los trabajadores de la salud que notificaron exposición a fluidos corporales procedían principalmente de los servicios de medicina interna, emergencia y cirugía. El mayor número de los accidentes correspondió a los médicos, principalmente residentes de posgrado. Exposición de tipo parenteral fue observada en 197 casos (179 percutáneas, y 18 salpicaduras en mucosas). Exposición cutánea se observó en 14 y combinada (piel y mucosas) 23 casos. El instrumento utilizado en 179 exposiciones percutáneas fue aguja con lumen en 48%. El fluido corporal involucrado fue la sangre en el 73% de los casos. La fuente fue conocida en 65% de las exposiciones. La profilaxis antirretroviral posexposición fue indicada inicialmente en 52% de los TS. Los efectos adversos se presentaron en 40%, en 7 casos fue motivo de abandono de tratamiento. El seguimiento se realizó en el 80% de los casos. Un trabajador de salud presentó Virus de Inmunodeficiencia Humana ocupacional...

Prospective study designed to assess the health workers at the Hospital Universitario de Caracas to notify body fluid exposure to Human Immunodeficiency Virus Surveillance System and Viral Hepatitis, from the years 1991-1999. The variables studied were: date and place of the accident, staff category, age, gender, fluid involved, type of exposure, instrument used, and baseline serology for Human Immunodeficiency Virus and Viral Hepatitis of health workers and index patient, type of prophylaxis antiretroviral, side effects and Human Immunodeficiency Virus seroconversion. Descriptive method was used series of cases which were analyzed by Epi-info. Version 5. During the study period were evaluated health workers 242 with body fluid exposure, 65% accidents were reported the past two years. 163 female and 79 male, mean age 43 years (range 21-65 years). Health workers who reported exposure to body fluids were mainly of Internal Medicine, Emergency and Surgery. The greatest numbers of injuries were doctors, mainly postgraduate residents. Parenteral exposure rate was observed in 197 cases (179 percutaneous, splash to mucous membranes 18). Dermal exposure was observed in 14 and combined (skin and mucosa) 23 cases. The instrument used in 179 percutaneous exposures was needle lumen in 48%. The body fluid blood was involved in 73% of cases. The source was known in 65% of exposures. Antiretroviral prophylaxis post exposure was initially indicated in 52% of the TS. Adverse events occurred in 40 %, in 7 cases was cause for withdrawals. The monitoring was performed in 80%. A case of Human Immunodeficiency Virus occupational in which it ruled out other risk factors

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INTRODUCCIÓN: la exposición accidental ocupacional a sangre y otros fluidos corporales es uno de los más frecuentes riesgos laborales, presentándose en el personal sanitario mundial alrededor de 3 millones de pinchazos/año con objetos cortopunzantes contaminados; su adecuada atención es indispensable para prevenir enfermedades infecciosas. OBJETIVO: Determinar la adherencia al protocolo de manejo de los accidentes de trabajo con riesgo biológico, las variables asociadas en las atenciones iniciales, y la oportunidad en los seguimientos recomendados al trabajador en una aseguradora de riesgos laborales (ARL) de Colombia. MATERIALES Y MÉTODOS: Se realiza un estudio descriptivo de corte transversal analizando todos los casos reportados a la ARL Colpatria entre el 1 de febrero del 2012 y el 28 de febrero de 2013. La recolección de los datos fue realizada por una entidad especializada en asesoramiento y acompañamiento de los casos mediante seguimiento telefónico, considerando variables sociodemográficas (edad, sexo, lugar de ocurrencia), propias del evento (tipo de accidente, fluido involucrado, parte de cuerpo afectada); se determinó la adherencia a la guía de manejo de acuerdo al cumplimiento de la misma. Se aplicaron pruebas de x² y regresión logística. RESULTADOS: se caracterizaron 1485 accidentes con riesgo biológico; los cargos como técnico en enfermería y personal encargado de la disposición de residuos presentaron la frecuencias más altas de exposición, con una proporción de 40,7 y 19,2%, respectivamente. La adherencia al esquema de hepatitis B fue del 70%, al de hepatitis C fue del 83%, al de VIH de 86% y el inicio de terapia postexposición del 89%; la oportunidad en los seguimientos varió entre el 18 y 41. DISCUSIÓN: se encuentran grandes falencias tanto en el proceso de disposición de cortopunzantes y cobertura de vacunación (prevención primaria), como en el diagnóstico de riesgo y en la oportunidad en el seguimiento de los casos estudiados (prevención secundaria).

INTRODUCTION: accidental occupational exposure to blood and other body fluids, is one of the most common occupational risks. In the world suffers medical staff about 3 million needlestick / sharps contaminated year, adequate care is essential to prevent and / or early detection of infectious diseases. OBJECTIVE: To determine adherence to protocol management of occupational accidents with biological risk associated variables in the initial care, and recommended follow-ups opportunity to work in a labor risk insurance (ARL) of Colombia, MATERIALS AND METHODS: We performed a cross-sectional descriptive study analyzing all cases reported to the ARL Colpatria between February 1, 2012 and February 28, 2013. The data collection was carried out by an entity specializing in advice and support by telephone follow-up cases, considering sociodemographic variables (age, sex, place of occurrence), own the event (type of accident involved fluid, body part affected) was determined adherence to management guidelines according to the fulfillment of the same. x² tests were applied and logistic regression. RESULTS: Were characterized 1485 cases of occupational exposure to bloodborne pathogen, the technician charges in nursing and staff responsible for waste disposal had the highest frequency exposure with a ratio of 40.7 and 19.2 % respectively. Scheme adherence hepatitis B was 70%, that of hepatitis C was 83%, the HIV of 86% and post-exposure therapy was started 89%, the opportunity in traces ranged between 18 and 41. DISCUSSION: are major flaws in the process both sharps disposal and vaccination coverage (primary prevention) and in the diagnosis of risk and the opportunity to monitor the cases studied (secondary prevention).

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Fundamento: los avances tecnológicos en el campo de la electrónica y la informática han proporcionado grandes mejoras en la seguridad y tolerancia a la hemodiálisis. La incorporación de biosensores que informan del desarrollo de la sesión de hemodiálisis en tiempo real ha supuesto una novedad relevante. Objetivo: profundizar sobre la utilidad y los principios de los biosensores aplicados a las máquinas actuales de la hemodiálisis. Método: se realizó una revisión de investigaciones publicadas en revista de nefrología biomed.uninet; asn-online.org y scielo., libros, revistas y manuales de funcionamiento de las máquinas de hemodiálisis seleccionándose 34 artículos científicos sobre los biosensores y su empleo. Desarrollo:revisión de los avances tecnológicos en las máquinas de hemodiálisis, los biosensores existentes, con las señales captadas por el sensor, su equivalente biológico y la señal clínica que nos aportan. Conclusiones: los biosensores son monitores que, a través de señales fisicoquímicas obtenidas del circuito extracorpóreo de sangre o del baño de diálisis, proporcionan datos de la eficacia de la sesión de hemodiálisis o de los cambios que produce en el medio interno del enfermo.

Background: technological advances in the fields of electronics and computer science have provided great improvements concerning safety and tolerance to haemodialysis. The incorporation of biosensors that inform about the progress of the haemodialysis session in real time has meant a significant innovation. Objective: to look in depth at the usefulness and principles of biosensors applied to current haemodialysis machines. Method: a review of researches published in nephrology journals, biomed.uninet, as-online.org, Scielo, books, other journals, and training manuals about the workings of haemodialysis machines, was made. Thirty-four scientific articles related to biosensors and the instructions for their use, were selected. Development: a review of the technological advances related to haemodialysis machines, the existing biosensors, the signals received by the sensor, the biological equivalent and the clinical signal they contribute with, was made. Conclusions: biosensors are monitors that, by means of physical-chemical signals obtained from the extracorporeal circuit of blood or of the dialysis bath, provide information of the effectiveness of the session of haemodialysis or of the changes that it produces in the organism of the patient.

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INTRODUCTION: Regenerative therapies using biomaterials require accurate information on interactions between the implanted material and the human body. To improve the process of bone regeneration it is necessary to obtain a better understanding of the influence of the surfaces on the early stages of osseointegration. This work aims to investigate the dynamic interaction between simulated body fluid (SBF) and titanium surfaces (Ti cp) immediately after their first contact. METHODS: Ti cp samples were passed through physicochemical treatments after immersion in acid solution, alkaline solution and solutions containing TiO2 and Ca2+, to obtain three different surfaces. These were characterized by electron microscopy and free energy estimates. The evaluation of the interaction with SBF was performed by measuring the dynamic contact angles after contacting the surfaces. RESULTS: The effects of SBF wettability were more significant on surfaces according to high energy estimates. A comparative analysis of the three types of surfaces showed that fluid spreading was greater in samples with greater polar components, indicating that the surface nature influences interactions in the early stages of osseointegration. CONCLUSION: The results indicate the influence of polar interactions in the dynamic wettability of the SBF. It is possible that these interactions can also influence cellular viability on surfaces. Based on these results, new experiments are being designed to improve the presented methodology as a tool for the evaluation of biomaterials without the need for in vivo experiments.

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A hipermatilação aberrante de regiões gênicas promotoras foi recentemente sugerida como meio de detecção do carcinoma epidermóide de cabeça e pescoço. Neste estudo nós avaliamos o status de metilação de um painel de 7 genes já relatados na literatura e sua correlação com lesões orais malignas e cancerizáveis de boca. Inicialmente, nós utilizamos amostras de enxágues salivares de pacientes com lesões benignas, displásicas e malignas para determinar a hipermetilação em regiões gênicas promotoras em pacientes de alto risco. Uma avaliação clínica de risco foi realizada e correlacionada com o diagnóstico histológico e status dos biomarcadores. A partir dos resultados analisados nas lesões intraorais, o gene DCC, que obteve a melhor performance entre os 7 genes, foi testado em lesões de queilite actínica e carcinoma epidermoide de lábio. Foram realizadas reações de PCR específica para metilação, quantitativa (Q-MSP) para os 7 genes (CCNA1, MGMT, MINT31, TIMP3, P16, DAPK, DCC) em enxágues salivares de 191 pacientes com lesões intraorais, e do gene DCC em 39 lesões de lábio. Análises de regressão logística e curva ROC foram utilizadas para avaliar a associação do status de metilação com o diagnóstico histológico e para estimar a acurácia da classificação respectivamente, nas amostras de enxágue salivar. Na análise multivariada, o diagnóstico displasia/ câncer foi associado com a idade (OR=1.3, 95% CI= (1.01-1.6, p=0.014) e a metilação do painel de 7 genes (OR=2.2, 95% CI=(1.34.0), p=0.006); a metilação do DCC também foi fortemente associada (OR=3.3, 95% CI=(1.7-6.6), p=0.004). Na análise multivariada, o diagnóstico histológico foi independentemente associado com a metilação do painel de 7 genes (OR=2.0, 95% CI=(1.1-3.6), p=0.027) ou do DCC (OR=2.8, 95% CI=(1.4-5.7), p=0.004)...

Aberrant promoter hypermethylation has been recently proposed as a means for detection of HNSCC in salivary rinses. Here we evaluate the ability of a previously reported 7-gene methylation panel status to correlate with premalignant and malignant oral lesions. We used a large prospective cohort of salivary rinses obtained from patients with benign, dysplastic, and cancer diagnoses to determine promoter hypermethylation in high-risk patients. Clinical risk assessment was performed and correlated with histological diagnosis and biomarker status. Also, a cohort of lip lesions was selected and methylation status of DCC gene was correlated with histology. Quantitative methylation-specific PCR (Q-MSP) was performed analyzing methylation status of 7 genes (CCNA1, MGMT, MINT31, TIMP3, P16, DAPK, DCC) in salivary rinses of 191 patients with oral lesion and 39 lip lesions. Logistic regression and receiver operating characteristic (ROC) analyses were used to examine the association of methylation status with histologic diagnosis and to estimate classification accuracy, respectively. On univariate analysis, diagnosis of dysplasia/cancer was associated with age (OR=1.3, 95% CI= (1.01-1.6, p=0.014) and 7-gene panel methylation (OR=2.2, 95% CI=(1.34.0), p=0.006); DCC methylation was also strongly associated (OR=3.3, 95% CI=(1.7-6.6), p=0.004). On multivariable modeling, histologic diagnosis was independently associated with 7 gene panel (OR=2.0, 95% CI=(1.1-3.6), p=0.027) or DCC (OR=2.8, 95% CI=(1.4- 5.7), p=0.004) methylation...

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A substituição de ossos, articulações e dentes por biomateriais é usualmente feita em cirurgias para aliviar a dor e recuperar a função dos tecidos afetados. Adequada resistência mecânica, boa resistência à corrosão no meio corpóreo, não provocar toxicidade ao corpo e longa permanência no local são algumas das principais características que um biomaterial deve possuir para ter sucesso na aplicação. Porém, no corpo humano a degeneração óssea, inflamações nas articulações, bem como o desgaste ou corrosão das próteses e implantes, freqüentemente ocorrem e trazem complicações clínicas (HE e HAGIWARA, 2006). Mo presente trabalho, amostras de titânio comercialmente puro e implantes dentários osseointegráveis na forma de cilindro com roscas, fabricados com titânio comercialmente puro (Ti cp) ASTM grau 4 foram analisados com quatro tipos de superfícies usadas comercialmente: Master Screw (usinada), Master Porous (Superfície tratada com ácido), Master Vulcano Actives (Superfície anodizada) e tratado com flúor. O objetivo deste estudo foi avaliar a bioatividade e a influência do tratamento da superfície do Ti cp mediante imersão em solução de fluído corpóreo simulado (SBF). Após imersão em SBF por 10, 20 e 30 dias, as amostras foram observadas no microscópio eletrônico de varredura caracterizadas por difração de raio X. Os resultados mostraram que entre as superfícies analisadas, a superfície com melhor biocompatibilidade avaliada pela deposição de íons da solução SBF foi a Vulcano; apesar dos tempos de imersão terem sido relativamente baixos, obteve-se um resultado significantivamento positivo após os tratamentos Porous e com flúor

The replacement of bones, articulations and tooth for biomaterials are usually made in sugeries to relieve the pain and to recover the function of the affected tissue. Suitable mechanical properties, high corrosion resistance in the human body environment, no toxicity and long time in the place are some characteristics that a biomaterial should present to have success in the application. However, in the human body the bone degeneration, inflammations problems, as well as the wear or corrosion of the prostheses and implants, frequently happens and brings clinical complications (HE and HAGIWARA, 2006). In the present work, samples of discs and dental implants with cylinder shape were machined with commercial pure titanium (Ti cp) ASTM grade 4 were machined with commercial pure titanium (Ti cp) ASTM grade 4 were analyzed. Four implant surfaces were used: Master Screw (machined), Master Porous (acid etched), Master Vulcano Actives (anodized) and immersed in fluorine. The goal of this study was to evaluate the bioactivity and the influence of the surface treatment on Ti cp 4 immersed in Simulated Body Fluid (SBF). After immersion in SBR for 10, 20 and 30 days, the samples were observed by scanning electron microscopy (SEM) and characterized by X ray diffraction. The results showed that among the studied surface, the best surface result of deposition of ions from the SBF solution was the Vulcano one. In spite of the immersion times have been relatively low, a significantly positive result was obtained with Porous and fluorine treatments

Assuntos