Factors associated with knowledge of the nursing staff at a teaching hospital on blood transfusion / Fatores associados ao conhecimento da equipe de enfermagem de um hospital de ensino sobre hemotransfusão / Factores asociados al conocimiento del equipo de enfermería sobre transfusión sanguínea en un hospital de enseñanza

AbstractObjective: to determine whether there is an association between knowledge of the nursing professionals about blood transfusion and the variables related to the professional aspects.Method: this is an observational, cross-sectional and quantitative study, carried out at a large general teaching hospital. The sample consisted of 209 nursing professionals, obtained by simple random sampling. For data collection, a checklist was used. In the univariate analysis, descriptive statistics and central trend and dispersion measures were used. In the bivariate analysis, Student's t-Test, analysis of variance and Pearson's correlation were used. To determine the predictors, multiple linear regression was applied. The Institutional Review Board (Opinion number 2434) approved the study.Results: the overall average knowledge score was 52.66%; in the Pre-transfusion Step, it corresponded to 53.38%; in the Transfusion Step 51.25% and, in the Post-transfusion Step, 62.68%. The factors related to knowledge were professional category and received training and/or guidance to accomplish the transfusion process (p<0.01).Conclusion: this study showed the influence of training and guidance on the knowledge and provided a diagnosis to identify the professionals' difficulties regarding the transfusion process.

ResumoObjetivo:verificar se há associação entre o conhecimento dos profissionais da equipe de enfermagem sobre hemotransfusão e as variáveis relacionadas aos aspectos profissionais.Método:trata-se de um estudo observacional, transversal, quantitativo, realizado em um hospital geral, de ensino e de grande porte. A amostra foi constituída por 209 profissionais da equipe de enfermagem, obtida por sorteio aleatório simples. A coleta de dados utilizou um instrumento do tipo checklist. Na análise univariada, utilizaram-se estatística descritiva e medidas de centralidade e de dispersão. Na análise bivariada, utilizaram-se o Teste t de Student, a análise de variância e a correlação de Pearson. Para determinar os preditores, utilizou-se a regressão linear múltipla. O estudo foi aprovado pelo Comitê de Ética em Pesquisa (Parecer n° 2434).Resultados:a média de escore geral de conhecimento foi de 52,66%, na Etapa Pré-transfusional foi de 53,38%; na Etapa Transfusional, 51,25%; e na Etapa Pós-transfusional, 62,68%. Os fatores relacionados ao conhecimento foram categoria profissional e receber treinamento e/ou orientação para a realização do processo transfusional (p<0,01).Conclusão:este estudo evidenciou a influência do treinamento e orientação sobre o conhecimento e forneceu um diagnóstico para a identificação das dificuldades dos profissionais relacionadas ao processo transfusional.

ResumenObjetivo:verificar si existe asociación entre el conocimiento de los profesionales del equipo de enfermería sobre transfusión sanguínea con las variables relacionadas a aspectos profesionales.Método:se trata de un estudio observacional, transversal, cuantitativo, realizado en un hospital general, de enseñanza y de gran porte. La muestra fue constituida por 209 profesionales del equipo de enfermería, obtenida por sorteo aleatorio simple. La recolección de datos utilizó un instrumento del tipo lista de verificación. En el análisis univariado, se utilizó la estadística descriptiva y las medidas de centralidad y de dispersión. En el análisis bivariado, se utilizaron el test t de Student, el análisis de variancia y la correlación de Pearson. Para determinar los factores de predicción, se utilizó la regresión linear múltiple. El estudio fue aprobado por el Comité de Ética en Investigación con dictamen n° 2434.Resultados:el promedio del puntaje general de conocimiento fue de 52,66%; en la Etapa de Pre-transfusión fue de 53,38%; en la Etapa de Transfusión, 51,25%; y, en la Etapa Post-transfusión, 62,68%. Los factores relacionados al conocimiento fueron: categoría profesional y recibir entrenamiento y/u orientación para la realización del proceso de transfusión (p<0,01).Conclusión:este estudio evidenció la influencia del entrenamiento y la orientación sobre el conocimiento y suministró un diagnóstico para la identificación de las dificultades de los profesionales relacionadas al proceso de transfusión.

Recombinant hepatitis C virus-envelope protein 2 interactions with low-density lipoprotein/CD81 receptors

Hepatitis C virus (HCV) envelope protein 2 (E2) is involved in viral binding to host cells. The aim of this work was to produce recombinant E2B and E2Y HCV proteins in Escherichia coli and Pichia pastoris, respectively, and to study their interactions with low-density lipoprotein receptor (LDLr) and CD81 in human umbilical vein endothelial cells (HUVEC) and the ECV304 bladder carcinoma cell line. To investigate the effects of human LDL and differences in protein structure (glycosylated or not) on binding efficiency, the recombinant proteins were either associated or not associated with lipoproteins before being assayed. The immunoreactivity of the recombinant proteins was analysed using pooled serum samples that were either positive or negative for hepatitis C. The cells were immunophenotyped by LDLr and CD81 using flow cytometry. Binding and binding inhibition assays were performed in the presence of LDL, foetal bovine serum (FCS) and specific antibodies. The results revealed that binding was reduced in the absence of FCS, but that the addition of human LDL rescued and increased binding capacity. In HUVEC cells, the use of antibodies to block LDLr led to a significant reduction in the binding of E2B and E2Y. CD81 antibodies did not affect E2B and E2Y binding. In ECV304 cells, blocking LDLr and CD81 produced similar effects, but they were not as marked as those that were observed in HUVEC cells. In conclusion, recombinant HCV E2 is dependent on LDL for its ability to bind to LDLr in HUVEC and ECV304 cells. These findings are relevant because E2 acts to anchor HCV to host cells; therefore, high blood levels of LDL could enhance viral infectivity in chronic hepatitis C patients.

Etiopatogenia de la esclerosis sistémica progresiva / Etiopathogenesis of systemic sclerosis

La esclerosis sistémica progresiva (ESP) es una enfermedad autoinmune crónica del tejido conectivo. Se caracteriza por una alteración vascular inicial, una respuesta inmune alterada con producción de autoanticuerpos y un exceso de síntesis y depósito de fibras de colágeno en la piel y tejido conectivo. La activación y el daño endotelial son eventos tempranos en la patogenia de la enfermedad; sin embargo, el factor gatillante continúa siendo desconocido. Se piensa que el evento principal sería la interacción entre eventos autoinmunes y cambios vasculares tempranos, lo cual resulta en la generación de fibroblastos activados considerados como las células efectoras de la enfermedad. Se reconocen dos subgrupos clínicos de ESP: la variedad cutánea limitada y la variedad cutánea difusa, las cuales presentan distintos patrones de compromiso orgánico, autoanticuerpos, evolución y sobrevida.

Progressive systemic sclerosis is a chronic autoimmune disease of connective tissue. It is characterized by early vascular changes, altered immune response with production of auto-antibodies, and excessive synthesis and deposition of collagen fibers in the skin and connective tissue. Activation and endothelial cell damage are early events in the pathogenesis of the disease, but the precise triggering event(s) remain elusive. The main event would be the interaction between autoimmune events early vascular changes, resulting in the generation of activated fibroblasts, regarded as effector cells of the disease. There are two major subgroups of SSc, the limited cutaneous and the diffuse cutaneous variety, which have distinct patterns of organ involvement, self-auto-antibodies, evolution and survival.

Avances sobre síndrome antifosfolípido / Advances in antiphospholipid syndrome

El Síndrome antifosfolípido (SAF) es una trombofilia adquirida, que se caracteriza por presentar eventos trombóticos recurrentes y complicaciones obstétricas en presencia de anticuerpos antifosfolípidos (aFL), los cuales son pesquisados por pruebas de laboratorio como anticoagulante lúpico y anticuerpos anticardiolipina. En esta revisión se muestran los aspectos más relevantes del SAF, destacando los avances en fisiopatología y criterios diagnósticos.

Anticuerpos anticélulas endoteliales en enfermedades sistémicas / Anti-endothelial cell autoantibodies in systemic diseases

Anti-endothelial cell autoantibodies (AECA), first described more then 30 years ago, represent a heterogeneous group of autoantibodies directed against poorly characterized antigens located in endothelial cell membranes, and have been reported in a variety of sistemic diseases. Although most of the target antigens for AECA are still not well identified, and AECA have been considered an epiphenomenon of vascular injury, new evidence suggests a pathogenic role, specially by inducing endothelial cell activation and apoptosis. The presence of AECA has been correlated with disease activity in SLE and systemic vasculitis such as Wegener's granulomatosis, Takayasu arteritis, and behçet's disease, and they could be valuable markers of disease activity. Other potential areas of clinical interest in diseases associated to AECA could be the serum thrombomodulin level, as marker of endothelial cell injury in neuropsychiatric lupus, and other vasculitides; and the determination of anti-heat shock protein antibodies including the Hsp60, as a new, non traditional risk factor for atherosclerosis in patient with lupus.

Isolation of Endothelial Progenitor Cells from Cord Blood and Induction of Differentiation by Ex Vivo Expansion

Endothelial progenitor cells (EPCs) have been reported to possess the capacity to colonize vascular grafts and hold promise for therapeutic neovascularization. However, limited quantities of EPCs have been the major factor impeding effective research on vasculoangiogenesis. In this study, cytokine and culture conditions necessary for the provision of large quantities of endothelial cells (ECs) were investigated. Cord blood was collected from 18 normal full-term deliveries and CD34+ cells were isolated by MACS system (Miltenyi Biotech, Bergish-Gladbach, Germany). To evaluate the effect of cytokines, CD34+ cells were cultured with various cytokine combinations, such as stem cell factor (SCF), flt3-ligand (FL), and thrombopoietin (TPO) with vascular endothelial growth factor (VEGF), interleukin-1beta, fibroblast growth factor-basic (FGF-b) as basic cytokines. The quantities of non-adherent and adherent cells were the greatest with SCF, FL and TPO. The addition of TPO to all other cytokines significantly increased the number of non-adherent and adherent cells (p< 0.05, Wilcoxon rank sum test). After four weeks of culture, adherent cells expressed endothelial specific markers such as KDR, CD31 and CD62E. Typical morphology of ECs was observed during culture, such as cord-like structure and cobblestone appearance, suggesting that the adherent cells were consistent with ECs. In this study, the experimental conditions that optimize the production of ECs for therapeutic neovascularization were described. And it was possibly suggested that TPO plays a major role in differentiation from EPCs to ECs.

Immune responses in histoplasmosis, a prototype of respiratory mycoses.

The cellular and molecular mechanisms of host defenses to histoplasmosis, a prototype of respiratory fungal infections are described. Although, cell-mediated acquired immunity is considered as a hallmark of protective immunity to histoplasmosis, the recent findings provide mounting evidence on the importance of natural cellular immunity in host resistance to fungal infections. The natural immunity to Histoplasma capsulatum infection is primarily mediated by natural killer cells, endothelial cells and platelets but mechanisms of intercellular communication and their interactions with the pathogen are not clearly defined.