Endocardite das válvulas das cavidades direitas: a importância da ecocardiografia na identificação da(s) estrutura(s) afectada(s)

A endocardite das válvulas das cavidades direitas do coração é rara. Ocorre geralmente em doentes com toxicofilia endovenosa, portadores de pacemaker (PMD), portadores de próteses valvulares ou cateter venoso central e ainda em doentes com cardiopatias congénitas. A Ecocardiografia constitui o gold standard na identificação da(s) estrutura(s) afetada (s) e permite a orientação terapêutica. Apesar de ser rara, a endocardite das cavidades direitas deve ser tida em conta durante a realização de ecocardiografia transtorácica e/ou transesofágica que vise o diagnóstico de endocardite. A profilaxia antibiótica deve ser sempre aplicada antes da realização de qualquer procedimento invasivo de acordo com as recomendações publicadas. Acentua-se a necessidade de educar a população, prevenindo-se assim complicações graves resultantes de procedimentos simples cada vez mais vulgares nas populações mais jovens, como a colocação de piercing. Os autores apresentam dois casos clínicos dessa patologia

The regularized visible fold revisited

The planar visible fold is a simple singularity in piecewise smooth systems. In this paper, we consider singularly perturbed systems that limit to this piecewise smooth bifurcation as the singular perturbation parameter $\epsilon\rightarrow 0$. Alternatively, these singularly perturbed systems can be thought of as regularizations of their piecewise counterparts. The main contribution of the paper is to demonstrate the use of consecutive blowup transformations in this setting, allowing us to obtain detailed information about a transition map near the fold under very general assumptions. We apply this information to prove, for the first time, the existence of a locally unique saddle-node bifurcation in the case where a limit cycle, in the singular limit $\epsilon\rightarrow 0$, grazes the discontinuity set. We apply this result to a mass-spring system on a moving belt described by a Stribeck-type friction law

Contact lens case cleaning procedures affect storage solution pH and osmolality

AB Purpose. To investigate pH and osmolality changes in the solutions stored in contact lens (CL) cases, when different case rinsing and drying methods are used on a daily basis. Methods. Four multipurpose solutions (Opti-Free Express, Solo-Care Aqua, Re-Nu Multiplus, and Complete) and two hydrogen peroxide systems (AOsept and Oxysept) were studied. Cases were filled with the solutions and kept sealed. After 8 h, the cases underwent different rinsing (rinsing; non-rinsing) and drying (air drying-AD; lint-free tissue drying-LFTD; non-drying-ND) procedures on a daily basis. Five cases of each rinsing/drying combination for each solution were evaluated. The pH and osmolality of the case-contained solution were evaluated on the 1st, 7th, 15th, and then, 30th day. Results. pH and osmolality increased significantly from day 1 to 30, except for Complete in which a significant decrease in pH was found. Rinsing vs. non-rinsing CL cases did not have any influence on the pH or osmolality, except for Oxysept, which showed a significantly higher osmolality value when cases were not rinsed. However, the drying procedure did influence both measurements; pH was significantly higher in the AD compared with the ND group (p < 0.05), and there was a significant difference in osmolality between the three drying conditions (p < 0.05), with the AD group showing the highest values, and the LFTD group showing the lowest. Conclusions. Osmolality and pH values are time and drying process-dependent in a CL case cleaning schedule. Regarding drying conditions, LFTD causes less increase in osmolality. Future studies should determine whether these changes might affect bacterial growth, lens parameters, or subject comfort during CL wear. (C) 2011 American Academy of OptometryPeer Reviewed