Global aphasia as a predictor of mortality in the acute phase of a first stroke / Afasia global prediz mortalidade na fase aguda de um primeiro acidente vascular cerebral isquêmico

OBJECTIVE: To establish whether vascular aphasic syndromes can predict stroke outcomes. METHOD: Thirty-seven adults were evaluated for speech and language within 72 hours after a single first-ever ischemic brain lesion, in blind association to CT and/or MR. RESULTS: Speech or language disabilities were found in seven (87.5 percent) of the eight deceased patients and twenty-six (89.7 percent) of the twenty-nine survivors. Global aphasia was identified in eleven patients, all with left hemisphere lesions (nine mute; five deceased), consisting on a risk factor for death in the acute stroke phase (ρ=0.022). Age (z=1.65; ρ>0.09), thrombolysis (ρ=0.591), infarct size (ρ=0.076) and side (ρ=0.649) did not significantly influence survival. Absence of aphasia did not predict a better evolution, regardless of the affected hemisphere. Prevalence of cardiovascular risk factors was similar for all patient groups. CONCLUSION: Global aphasia in acute stroke can adversely affect prognosis, translated into impairment of dominant perisylvian vascular territories, with mutism as an important semiological element.

OBJETIVO: Determinar se síndromes afásicas na fase aguda do infarto cerebral influenciam o prognóstico. MÉTODO: Avaliação para fala e linguagem de 37 adultos dentro de 72 horas após um primeiro infarto cerebral, em associação topográfica cega com TC e/ou RM. RESULTADOS: Detectaram-se afasias ou disartria em 7 (87,5 por cento) dos 8 pacientes falecidos, e em 26 (89,7 por cento) dos 29 sobreviventes. Afasia global foi identificada em 11 pacientes, todos com lesões no hemisfério esquerdo (cinco óbitos; mutismo em nove), consistindo em fator de risco para mortalidade na fase aguda do acidente vascular cerebral isquêmico (ρ=0,022). Idade (z=1,65; ρ>0,09), trombólise (ρ=0,591), dimensões da lesão (ρ=0,076) e lado (ρ=0,649) não afetaram significativamente a sobrevivência. Ausência de afasia não prenunciou melhor evolução. Fatores de risco cardiovascular tiveram similar prevalência para todos os grupos de pacientes. CONCLUSÃO: Afasia global na fase aguda do infarto cerebral pode aumentar mortalidade, demonstrando envolvimento de território vascular perisylviano dominante, tomando-se mutismo como importante elemento semiológico.

Microemulsão: um promissor carreador para moléculas insolúveis / Microemulsion: a promising carrier system for insoluble compounds

Microemulsão (ME) é um sistema que foi descoberto por Hoar e Schulman no ano de 1943 e que é termodinamicamente estável e isotropicamente translúcido de dois líquidos imiscíveis (óleo/água), estabilizados por um filme interfacial de tensoativos. O estudo de sistemas microemulsionados se baseia nas suas três teorias de formação: (1) teoria da solubilização, (2) teoria da tensão interfacial e (3) teoria termodinâmica. A estrutura formada é influenciada pelas propriedades físico-químicas dos componentes utilizados e da razão entre os componentes. O objetivo desta revisão foi avaliar o estado da arte de sistemas microemulsionados enfatizando uma abordagem teórica. Além disso, os recentes avanços sobre a aplicabilidade clínca e utilização como carreador de moléculas insolúveis foram discutidas.

Microemulsions (ME) are thermodynamically stable and isotropic systems of two immiscible liquids (oil/water), stabilized by an interfacial film of surfactants, discovered by Hoar and Schulman in 1943. The study of ME formation is based on three areas of theory: (1) solubilization, (2) interfacial tension and (3) thermodynamics. ME structures are influenced by the physicochemical properties and proportions of their ingredients. The goal of this review is to assess the state of the art of microemulsified systems, from a theoretical viewpoint. Also, recent progress on their clinical application and use as carriers for insoluble compounds is discussed.

Administração cutânea de fármacos: desafios e estratégias para o desenvolvimento de formulações transdérmicas / Cutaneous administration of drugs: challenges and strategies for the development of transdermal formulations

O desenvolvimento de formulações para aplicação na pele é uma estratégia interessante para transportar fármacos cuja ação é a própria pele, representando uma alternativa para superar aspectos indesejados relacionados às características farmacocinéticas e farmacodinâmicas dos fármacos. No entanto, a pele apresenta camadas que formam uma barreira à penetração de fármacos. Desse modo, estratégias têm sido pesquisadas e os modernos estudos farmacêuticos apontam para o uso de métodos físicos e químicos, norteados no desenvolvimento de novas formas farmacêuticas, as quais devem apresentar propriedades físico-químicas e parâmetros farmacotécnicos adequados para o uso transdérmico.

The development of formulations for skin application is a good strategy for the delivery of drugs whose target is the skin itself, which avoids some unwanted effects of treatment arising from the pharmacokinetic and pharmacodynamic properties of drugs. However, the skin has layers that resist the penetration of drugs. Thus, new strategies have been researched and the latest pharmaceutical studies point to the use of physical and chemical methods aimed at the development of new drug delivery systems, exhibiting physicochemical properties and pharmaceutical parameters suitable for transdermal administration.

The immunomodulator glatiramer acetate influences spinal motoneuron plasticity during the course of multiple sclerosis in an animal model

The immunomodulador glatiramer acetate (GA) has been shown to significantly reduce the severity of symptoms during the course of multiple sclerosis and in its animal model - experimental autoimmune encephalomyelitis (EAE). Since GA may influence the response of non-neuronal cells in the spinal cord, it is possible that, to some extent, this drug affects the synaptic changes induced during the exacerbation of EAE. In the present study, we investigated whether GA has a positive influence on the loss of inputs to the motoneurons during the course of EAE in rats. Lewis rats were subjected to EAE associated with GA or placebo treatment. The animals were sacrificed after 15 days of treatment and the spinal cords processed for immunohistochemical analysis and transmission electron microscopy. A correlation between the synaptic changes and glial activation was obtained by performing labeling of synaptophysin and glial fibrillary acidic protein using immunohistochemical analysis. Ultrastructural analysis of the terminals apposed to alpha motoneurons was also performed by electron transmission microscopy. Interestingly, although the GA treatment preserved synaptophysin labeling, it did not significantly reduce the glial reaction, indicating that inflammatory activity was still present. Also, ultrastructural analysis showed that GA treatment significantly prevented retraction of both F and S type terminals compared to placebo. The present results indicate that the immunomodulator GA has an influence on the stability of nerve terminals in the spinal cord, which in turn may contribute to its neuroprotective effects during the course of multiple sclerosis.