Properties of Adsorbed Bovine Serum Albumin and Fibrinogen on Self-Assembled Monolayers

International audienceWe have studied kinetics of adsorption and properties of adsorbed bovine serum albumin (BSA) and fibrinogen (Fb) on a hydrophobic octyl surface, a hydrophilic amine surface, and a mixture of octyl and amine self-assembled monolayer (SAM) and newly synthesized hybrid SAM by using quartz crystal microbalance (QCM). In addition, we have proposed a combined kinetic and mass transfer constrained protein adsorption model. The model is fitted to a change in resonance frequency, Delta F-n/n versus time data obtained from QCM to get the kinetic rate constants, mass transfer coefficient, and spreading of adsorbed proteins. Initial rate of adsorption increases with a decrease in surface energy of the substrate. The equilibrium adsorbed amount of BSA on the hybrid surface is less than that on the mixed surface and lies in between that on octyl and amine surfaces and that of Fb is the least on hybrid surface. The analysis of variation of the dissipation factor, Delta D, with Delta F-n/n indicates that BSA is more flexible than Fb and the adsorbed layer of both proteins is softest on the hybrid surface. The relaxation times of adsorbed proteins are the slowest on the octyl surface, while those on the hybrid surface are the fastest. The analysis of secondary structures of proteins using ATR-FTIR suggests secondary structures of the proteins change during adsorption. The content of alpha-helix of the proteins increases due to adsorption on the amine surface, while that decreases on all other surfaces. The total content of a-helix and beta-sheet strongly depends on the adsorbed mass of the proteins and is weakly dependent related to elasticity and viscosity of the adsorbed proteins, respectively

CONSULTA DE ENFERMAGEM EM GERIATRIA: TÓPICOS A SEREM ABORDADOS NO EXAME FÍSICO — PARTE II.

Neste trabalho são apresentados os itens considerados importantes para o exame físico do indivíduo idoso, além de outros tópicos que são fundamentais para a consulta de Enfermagem, complementando o artigo intitulado: "Consulta de Enfermagem em Geriatria: tópicos a serem abordados na Entrevista — parte I".The author approachers physycal exam in elderly and other items that are essential to nurses consultation. This article completes the topic Nurses consultation on Geriatrics —part I

Prevalence study of mental disorders in an Italian region. Preliminary report

Background: Mental disorders are a major public health problem. However, over the last few years, there have been few studies aimed at evaluating their diffusion. Therefore, this study aimed at evaluating: the prevalence of the most frequent psychiatric disorders in the general population residing in Tuscany using a clinical scale administered by trainee in psychiatry. Methods: The study was carried out on a representative sample of the general population aged > 18 years, randomly extracted from the register of patients in the Tuscany region, adopting a proportional sampling method stratified by gender, age group and Local Health Units (LHU). Each person was contacted by letter followed by a phone call from an operator who makes an appointment with the trainee in psychiatry. The diagnostic interview conducted was the Mini-International Neuropsychiatric Interview (MINI). Point and lifetime prevalence by gender and age group were calculated. Differences and associations were considered statistically significant if their p-values were less than 0.05. Results: Of the 408 people involved, 390 people were enrolled (of which 52.6% female). The 28.5% of the sample had been affected by a psychiatric disorder during their lifetime. In their lifetime, the most represented psychiatric disorders were major depressive episode (20.4%), major depressive disorder (17.0%) and panic disorder (10.3%), more frequent in the female than the male group. Current conditions were predominantly major depressive episode (3.1%) and agoraphobia (2.8%). A 5.9% rate of current suicidal ideation was also found. Conclusions: In the general population, 28.5% of people reported a psychiatric disorder during their lifetime. This prevalence is considerably higher than that reported in a previous study carried out in central Italy