Ortodeoxia recorrente e foramen ovale patente.

Introdução: Foramen ovale patente (FOP) ocorre em até 25% dos adultos saudáveis. Pode favorecer embolização paradoxal, enxaqueca e insuficiência respiratória (IR). Apresenta-se caso de IR e ortodeoxia por shunt direito-esquerdo via FOP sem evidência prévia de aumento da pressão intra-auricular direita. Encerramento do FOP resolveu eficazmente IR. Caso clínico: Homem, 52 anos. Mieloma múltiplo IgA/k diagnosticado um ano antes. Internado por IR hipoxémica grave com ortodeoxia e má resposta à oxigenoterapia, após colocação de cateter venoso central (CVC) na subclávia direita. Referia parestesias e alterações visuais inespecíficas, após manipulações do CVC. Características da IR sugeriam shunt entre circulação pulmonar e sistémica. Sem evidência clínica ou imagiológica de shunt intra-pulmonar. Ecocardiograma transtorácico com contraste: shunt direito- -esquerdo. Ecocardiograma transesofágico: FOP. Cateterismo cardíaco (após resolução espontânea da IR): sem shunt. Uma semana depois recorreu IR grave, que resolveu (bem como queixas neurológicas) com encerramento do FOP. Discussão: IR por shunt intra-cardíaco sem aumento da pressão nas cavidades direitas é de difícil interpretação hemodinâmica. Raros relatos (em adultos) associam esta entidade a anomalias anatómicas, que favorecerão shunt por orientação preferencial do fluxo sanguíneo para o FOP. São exemplos parésia diafragmática direita e ectasia da aorta ascendente, identificadas no doente apresentado. O papel do CVC, colocado imediatamente antes da IR, é especulativo. O completo sucesso terapêutico após encerramento do FOP apoia o diagnóstico. Conclusão: Avaliar correctamente IR (pesquisar ortodeoxia e resposta à oxigenoterapia) permite suspeitar de shunt, que se diagnostica utilizando meios acessíveis, seguros e rentáveis. Shunt intra-cardíaco sem aumento da pressão à direita deve ser considerado porque tem tratamento eficaz. Background: Patent foramen ovale (PFO) occurs in 25% of healthy adults. It can lead to paradoxical embolization, migraine and respiratory failure (RF). The authors present a case of RF and orthodeoxia due to a rightto- left shunt via a PFO without previous elevation of right atrial pressure. Closure of the PFO effectively resolved the RF. Case report: A 52-year-old man, with IgA-k multiple myeloma diagnosed one year before, was admitted for severe hypoxemic RF, with orthodeoxia and poor response to oxygen supplementation, after placement of a central venous catheter (CVC) in the right subclavian vein. The patient reported paresthesia and nonspecific visual changes after manipulation of the CVC. The RF suggested a shunt between the pulmonary and systemic circulations. There was no clinical or radiological evidence of an intrapulmonary shunt. Contrast echocardiography showed a right-to-left shunt and transesophageal echocardiography revealed a PFO. Cardiac catheterization, after spontaneous resolution of the RF, showed no shunt. A week later, severe RF recurred. Complete resolution of respiratory dysfunction and neurological symptoms was seen after PFO closure. Discussion: RF due to an intracardiac shunt without increased right-sided pressure is hemodynamically difficult to interpret. A few reports (in adults) relate this entity to anatomical anomalies, which can lead to a shunt by directing blood flow preferentially to the PFO. Examples include right diaphragmatic paresis and ectasia of the ascending aorta, which were observed in this patient. The role of the CVC, which was placed immediately before the RF, is uncertain. Complete therapeutic success after closure of the PFO supports the diagnosis. Conclusion: Correct evaluation of RF (by investigating orthodeoxia and response to oxygen therapy) enables the suspicion of a shunt, which can be confirmed through simple, safe and cost-effective exams. Intracardiac shunt without increased rightsided pressure should be considered because it can be successfully treatment

Water activity in lamellar stacks of lipid bilayers: "Hydration forces" revisited

Water activity and its relationship with interactions stabilising lamellar stacks of mixed lipid bilayers in their fluid state are investigated by means of osmotic pressure measurements coupled with small-angle x-ray scattering. The (electrically-neutral) bilayers are composed of a mixture in various proportions of lecithin, a zwitterionic phospholipid, and Simulsol, a non-ionic cosurfactant with an ethoxylated polar head. For highly dehydrated samples the osmotic pressure profile always exhibits the "classical" exponential decay as hydration increases but, depending on Simulsol to lecithin ratio, it becomes either of the "bound" or "unbound" types for more water-swollen systems. A simple thermodynamic model is used for interpreting the results without resorting to the celebrated but elusive "hydration forces"Comment: 24 pages, 12 figures. Accepted for publication in The European Physical Journal

Developing a site-conditions map for seismic hazard Assessment in Portugal

The evaluation of site effects on a broad scale is a critical issue for seismic hazard and risk assessment, land use planning and emergency planning. As characterization of site conditions based on the shear-wave velocity has become increasingly important, several methods have been proposed in the literature to estimate its average over the first thirty meters (Vs30) from more extensively available data. These methods include correlations with geologic-geographic defined units and topographic slope. In this paper we present the first steps towards the development of a site–conditions map for Portugal, based on a regional database of shear-wave velocity data, together with geological, geographic, and lithological information. We computed Vs30 for each database site and classified it according to the corresponding geological-lithological information using maps at the smallest scale available (usually 1:50000). We evaluated the consistency of Vs30 values within generalized-geological classes, and assessed the performance of expedient methodologies proposed in the literature

Experimental realization of the Yang-Baxter Equation via NMR interferometry

The Yang-Baxter equation is an important tool in theoretical physics, with many applications in different domains that span from condensed matter to string theory. Recently, the interest on the equation has increased due to its connection to quantum information processing. It has been shown that the Yang-Baxter equation is closely related to quantum entanglement and quantum computation. Therefore, owing to the broad relevance of this equation, besides theoretical studies, it also became significant to pursue its experimental implementation. Here, we show an experimental realization of the Yang-Baxter equation and verify its validity through a Nuclear Magnetic Resonance (NMR) interferometric setup. Our experiment was performed on a liquid state Iodotrifluoroethylene sample which contains molecules with three qubits. We use Controlled-transfer gates that allow us to build a pseudo-pure state from which we are able to apply a quantum information protocol that implements the Yang-Baxter equation.Comment: 10 pages and 6 figure

Application of a 235 rRNA Fluorescent In Situ Hybridization method for rapid detection of Salmonella sp. in slaughtered pigs

Pork products contamination during the slaughter process represents an important vehicle of Salmonella sp. dissemination to humans. It\u27s urgent to develop rapid, sensitive and accurate methods that allow the detection of a large number of Sa/monel/a-positive samples, in order to control these risks efficiently and in a practical time. This study evaluates the suitability of Fluorescent In Situ Hybridization (FISH) method as a rapid screening tool for Salmonella sp. deteclton in pork carcasses, as well in some risk tissues (ileum, ileocolic and mandibular lymph nodes and tonsils), which could be involved in Salmonella contamination during slaughter process. For that, FISH was comparatively analysed with the labour intenstve reference microbiological culture method (ISO 6579:2002) whose results were previously published by the same authors