Adesão à terapia antiretroviral para HIV/AIDS

A não-adesão à terapêutica antiretroviral altamente eficaz (HAART) é considerada, no plano individual, como um dos mais ameaçadores perigos para a efetividade do tratamento da pessoa com HIV/aids e para a disseminação de vírus-resistência, no plano coletivo. Assim, o objetivo deste estudo foi analisar, mediante revisão de literatura, os fatores de risco para não-adesão à HAART, além de agrupá-los e relacioná-los à pessoa em tratamento, à doença, ao tratamento e ao serviço de saúde e suporte social. A literatura aponta para a necessidade da realização de estudos que avaliem aspectos socioculturais, crenças, qualidade do serviço prestado, relações do cliente com a equipe multiprofissional e outros referentes à raça e aos efeitos colaterais dos anti-retrovirais. Estes estudos visam a favorecer o estabelecimento de estratégias que melhorem a adesão dos clientes à HAART, ao mesmo tempo em e que contribuem para a construção e exercício da cidadania

Timing of potential and metabolic brain energy

The temporal relationship between cerebral electro-physiological activities, higher brain functions and brain energy metabolism is reviewed. The duration of action potentials and transmission through glutamate and GABA are most often less than 5 ms. Subjects may perform complex psycho-physiological tasks within 50 to 200 ms, and perception of conscious experience requires 0.5 to 2 s. Activation of cerebral oxygen consumption starts after at least 100 ms and increases of local blood flow become maximal after about 1 s. Current imaging technologies are unable to detect rapid physiological brain functions. We introduce the concepts of potential and metabolic brain energy to distinguish trans-membrane gradients of ions or neurotransmitters and the capacity to generate energy from intra- or extra-cerebral substrates, respectively. Higher brain functions, such as memory retrieval, speaking, consciousness and self-consciousness are so fast that their execution depends primarily on fast neurotransmission (in the millisecond range) and action-potentials. In other words: brain functioning requires primarily maximal potential energy. Metabolic brain energy is necessary to restore and maintain the potential energy

Cationic liposome–microtubule complexes: Pathways to the formation of two-state lipid–protein nanotubes with open or closed ends

Intermolecular interactions between charged membranes and biological polyelectrolytes, tuned by physical parameters, which include the membrane charge density and bending rigidity, the membrane spontaneous curvature, the biopolymer curvature, and the overall charge of the complex, lead to distinct structures and morphologies. The self-assembly of cationic liposome–microtubule (MT) complexes was studied, using synchrotron x-ray scattering and electron microscopy. Vesicles were found to either adsorb onto MTs, forming a “beads on a rod” structure, or undergo a wetting transition and coating the MT. Tubulin oligomers then coat the external lipid layer, forming a tunable lipid–protein nanotube. The beads on a rod structure is a kinetically trapped state. The energy barrier between the states depends on the membrane bending rigidity and charge density. By controlling the cationic lipid/tubulin stoichiometry it is possible to switch between two states of nanotubes with either open ends or closed ends with lipid caps, a process that forms the basis for controlled chemical and drug encapsulation and release