ABSTRACT The chemical modification of chitosan (CH) from shrimp shells (Litopenaeus vannamei) was performed with amino acids: L-leucine (Leu) and L-tyrosine (Tyr), in order to change some of its physical and chemical properties, which allow the enhancement of the applications of chitosan in biomedical and pharmacological areas. The characterization of chitosan derivatives (CH-CH-Leu and Tyr) was performed by infrared spectroscopy studies (ATR-FTIR) to verify the new structure of the modified compounds. The thermal stability was analyzed by thermogravimetry (TGA). Solubility tests were carried out, where it was observed that the obtained derivatives are soluble in aqueous solutions at neutral and alkaline pH values, unlike the chitosan that is only soluble under acid pH conditions. The cytotoxicity of the derivatives was analyzed by hemocompatibility tests with human erythrocytes. Subsequently, membranes were obtain from the derivatives of CH-Leu and CH-Tyr, and contact angle was measured. The process of biodegradability in these membranes was studied through hydrolysis processes in H2O and phosphate buffered saline (PBS), pH 7.4 at 37ºC during time intervals of 24, 72 and 168 h. Scaffolds were prepared using the electrospinning technique to be able to prepare a mixture between poly (vinyl alcohol) (PVA) and CH derivatives (given their solubility in water) and the morphology was studied using scanning electron microscopy (SEM). In general, FTIR spectroscopy, TGA thermal analysis and SEM served as tools to verify the modification, and these derivatives allow to expand the physical and chemical properties of neat chitosan, mainly in terms of its solubility, allowing this novel biomaterial to be used in multiple applications, highlighting that they can be mixed with synthetic polymer phases which opens windows for the use of this interesting biopolymer.

RESUMEN Se realizó la modificación química de quitosano (CH) proveniente de conchas de camarón (Litopenaeus vannamei) con aminoácidos: L-leucina (Leu) y L-tirosina (Tyr), con el fin de variar algunas de sus propiedades físicas y químicas, y ampliar su uso en la fabricación de películas y andamios, potenciando las aplicaciones del quitosano en áreas biomédicas y farmacológicas. Los derivados (CH-Leu y CH-Tyr) fueron caracterizados mediante estudios de espectroscopia infrarrojo (ATR-FTIR) para verificar la estructura de los productos modificados y las propiedades térmicas fueron analizadas mediante termogravimetría (TGA). Se realizaron ensayos de solubilidad, donde se observó que los derivados obtenidos son solubles en disoluciones acuosas a valores de pH neutro y alcalino, a diferencia del quitosano que solo es soluble bajo condiciones de pH ácido. La citotoxicidad de los derivados fue analizada mediante ensayos de hemocompatibilidad con eritrocitos humanos. Posteriormente se realizaron membranas a partir de los derivados de CH-Leu y CH-Tyr, y se determinó el ángulo de contacto. El proceso de biodegradabilidad en membranas se estudió a través de procesos de hidrólisis en H2O y buffer fosfato salino (PBS), pH 7,4 a 37ºC durante intervalos de tiempo de 24, 72 y 168 h. Los andamios fueron preparados usando la técnica de electrospinning al preparar una mezcla entre poli(vinil alcohol) (PVA) y los derivados de CH (dada la solubilidad mostrada en agua), y la morfología de las fibras fue estudiada mediante microscopía electrónica de barrido (MEB). En general, los resultados obtenidos por FTIR, TGA y MEB sirvieron como herramientas para verificar la modificación, y estos derivados permiten ampliar las propiedades físicas y químicas del quitosano puro, principalmente en cuanto a su solubilidad, permitiendo que este novedoso biomaterial sea empleado en múltiples aplicaciones, resaltando que pueden ser mezclados con fases poliméricas sintéticas lo cual abre ventanas para el uso de este interesante biopolímero.

Abstract The aim of this study was to evaluate the cytotoxic effect, degree of conversion (% DC), Vickers hardness (VH), and surface morphology of composite resins. Eleven resins, nine bulk-fill resins, and two conventional resins were evaluated. Each material was sampled to evaluate DC (using FTIR), VH, cytotoxicity (using MTT and Neutral Red - NR test), surface morphology (using SEM and AFM), and organic filler (using EDS). All statistical tests were performed with SPSS and the level of significance was set at 0.05. MTT revealed that the materials presented low or no cytotoxic potential in relation to the control. Opus was the resin with the lowest cell viability at a 1:2 concentration at 72 h (32%) and at 7 days (43%), but that significantly increased when the NR test was applied at a 1:2 concentration after 7 days. Thickness and surface subjected to polymerization had no influence on DC, and differences were observed only between the materials. In the microhardness test, statistical differences were observed between the evaluated thicknesses. The bulk-fill resins analyzed in this study exhibited low and/or no cytotoxicity to L929 cells, except for Opus, which showed moderate cytotoxicity according to the MTT assay. When the NR test was used, results were not satisfactory for all composites, indicating the need for different methodologies to evaluate the properties of these materials. The assessed resins demonstrated acceptable physicomechanical properties.

A entorse lateral do tornozelo é umas das lesões mais comuns em atletas e adultos fisicamente ativos. A utilização de instrumentos de avaliação confiáveis e válidos é fundamental na determinação da intervenção terapêutica adequada e, portanto, do sucesso do tratamento. O objetivo deste trabalho foi fazer um levantamento crítico, por meio de uma análise sistemática da literatura, dos instrumentos de medida adequados (questionários e escalas funcionais) disponíveis para a avaliação dos indivíduos que sofreram entorse lateral do tornozelo. Após busca nos bancos de dados Medline e Scielo foram incluídos 11 questionários para avaliação funcional do tornozelo. A escala funcional de extremidade inferior LEFS (Lower extremity functional scale) e a medida funcional de pé e tornozelo FAAM (Foot and ankle ability measure) foram as que apresentaram melhor qualidade metodológica, além de mais informações sobre suas propriedades de medida e suas aplicações práticas - mas não foram traduzidas para o português. Foram encontrados dois questionários traduzidos e adaptados para a população brasileira, o instrumento de instabilidade de tornozelo CAIT (Cumberland Ankle Instability Tool) e a escala de tornozelo e retropé AOFAS (American Orthopaedic Foot and Ankle Society - ankle-hindfoot scale). A AOFAS apresentou uma análise mais completa de suas propriedades, sendo portanto o instrumento mais recomendado para avaliação funcional do complexo pé-tornozelo atualmente no Brasil.

Lateral ankle sprain is the most common injury among athletes and physically active adults. The adoption of valid and reliable clinical assessment instruments is basic for determining the most adequate therapeutic intervention, hence to achieve better rehabilitation. This is a systematic literature review to search for available and reliable outcome measures (questionnaires and functional scales) in the assessment of individuals who suffered lateral ankle sprain. After a search in Medline and Scielo databases a total of 11 instruments were selected and critically analysed. The Lower Extremity Functional Scale and the Foot and Ankle Ability Measure showed the best methodological properties and provided more information concerning measurement features and clinical application (but have not been translated into Portuguese). Two instruments were found that were translated and culturally adapted for the Brazilian people, the CAIT (Cumberland Ankle Instability Tool) and the AOFAS (American Orthopaedic Foot and Ankle Society - ankle-hindfoot scale). The AOFAS was found to present a more thorough analysis of its properties and applicability, being thus suggested to be used for functional assessment of ankle and hindfoot in Brazil.

Objetivos: verificar os níveis de leptina em pacientes com síndrome dos ovários policísticos (SOP) e suas relações com a testosterona, o estradiol, o FSH e a insulina. Métodos: estudo transversal realizado com 40 pacientes portadoras de SOP, divididas em dois grupos, de acordo com o seu índice de massa corporal (IMC): Grupo I (n = 20): pacientes obesas (IMC >28 kg/m²) e Grupo II (n = 20): pacientes não-obesas (IMC <28 kg/m²). Resultados: foi observada diferença significativa na relação glicemia/insulina entre os dois grupos (p=0,043). Os níveis de leptina se mostraram fortemente correlacionados com o IMC (p<0,001). Verificou-se que, eliminado o efeito do IMC, por meio de análise de regressão multivariada, a dosagem da insulina (p=0,194), do FSH (p=0,793), das testosteronas total (p=0,441) e livre (p=0,422), e a relação glicemia/insulina (p=0,166) não influenciaram a concentração de leptina. Entretanto, observou-se uma correlação entre as concentrações de leptina e de estradiol (p=0,043). Conclusão: existe correlação entre os níveis de leptina, o IMC e as concentrações de estradiol, em mulheres portadoras de SOP.

Purpose: to investigate leptin levels in patients with polycystic ovary syndrome (PCOS), and relationships with testosterone, estradiol, follicle-stimulating hormone (FSH) and insulin levels. Methods: transversal study on 40 patients with PCOS divided into two groups: Group I (n = 20)- obese women (body mass index - BMI > or = 28 kg/m²), and Group II (n = 20) - non obese women (BMI <28 kg/m²). Results: BMI was different between the two groups (p=0.04). We observed that leptin concentrations were significantly correlated with BMI (p<0.001). After adjusting for BMI, no correlation between leptin, insulin (p=0.194), FSH (p=0.793), and total (p=0.441) and free (p=0.422) testosterone was found. However, we only observed positive correlations between leptin and estradiol (p=0.043). Conclusions: there is a strong correlation between leptin levels, BMI and estradiol levels in women with PCOS.

A endocardite infecciosa (EI) acometendo próteses valvares é uma complicação freqüente, sendo tratada geralmente com cirurgia, devido ao seu difícil controle clínico e má resposta à antibioticoterapia. Este relato descreve o caso de uma paciente com EI, acometendo simultaneamente as biopróteses aórtica (Ao) e mitral (Mi) após vinte e quatro meses de cirurgia de implantes valvares, submetida a tratamento cirúrgico conservador, e com resultado favorável. Discutem-se as vantagens deste procedimento em situações específicas.

Infective endocarditis is a frequent complication for valvar prosthesis currently treated with surgery, orving to its difficult control and poor response to therapy with antibiotics. Although conservative surgery for infective endocarditis of prosthesis is not a procedure of choice, this report shows a case of infective endocarditis of aortic and mitral prosthesis, after 24 months of implantation, treated by conservative surgery with favorable outcome.