A experiência dos talassêmicos adultos ao tratamento

El objetivo de este estudio fue analizar los sentidos dados por los talasémicos adultos a su experiencia con el tratamiento, con base en la antropología médica y en el método del relato oral. Para la recolección de datos usamos entrevistas y seguimos el análisis temático inductivo. Participaron once adultos jóvenes, seis del sexo masculino; con edades, niveles educacionales y profesiones, distintas. Los sentidos da la experiencia son presentados por el tema "La vida del portador de talasemia con el tratamiento". El tema destaca la identidad de ser diferente por: el trazo de la enfermedad, el reconocimiento de la importancia de la adhesión al tratamiento, las dificultades en mantener sus funciones sociales y los episodios de irregularidad en la terapia y sus justificaciones. Aprendimos que los portadores están resignados con su condición y emplean la estrategia de normalización para el control de la enfermedad y para justificar la irregularidad en el tratamiento.O objetivo neste estudo foi analisar os sentidos dados pelos talassêmicos adultos à sua experiência em relação ao tratamento, com base na antropologia médica e no método do relato oral. Para a coleta de dados, usaram-se entrevistas e seguiu-se a análise temática indutiva. Participaram onze adultos jovens, seis do sexo masculino; com idades, níveis educacionais e profissões distintas. Os sentidos são apresentados pelo tema "a vida do portador de talassemia com o tratamento". O tema destacou a identidade de diferença pelo traço da doença, o reconhecimento da importância da adesão ao tratamento, as dificuldades em manterem suas funções sociais, os episódios de irregularidade na terapia e suas justificativas. Apreendeu-se que os portadores estão resignados com sua condição, empregam a estratégia de normalização para o controle da doença e justificaram a irregularidade no tratamento.This study, based on medical anthropology and oral reports, analyzes the meanings attributed by thalassemic adults to their experiences with the treatment. Interviews were used to collect data, which were analyzed through inductive thematic analysis. Eleven young adults, six of whom were men, at different ages, with different educational levels and occupations participated in the study. The meanings are discussed through the theme "the lives of patients with thalassemia in relation to their treatment". This core meaning highlights the difference made in their identity by having the disease trait, the recognition of the importance of adhering to their treatment, the difficulties in maintaining their social functions, the patients' irregular treatment adherence and their justifications for non-adherence to their treatment. Thalassemic patients conform to their condition and employ a normalization strategy to control the disease and justify irregular treatment adherence

El alta hospitalario en la evaluación de pacientes y cuidadores: una revisión integrada de la literatura

OBJECTIVE: To evaluate hospital discharge among patients and their caregivers. METHODS: A integrative literature review was performed in the database of Pubmed, CINAHL and Lilacs from 2000 and 2005, focusing on the adult patient discharge and elderly with clinical-surgical problems, published in the English or Portuguese language. RESULTS: The population was made up of 54 publications and the sample was made up of 23 papers, which were sorted into two theme categories: 13 focused on the effectiveness and 10 on the process inefficiency. CONCLUDING REMARKS: In the subjects standpoints, the effectiveness of the discharge planning stems to the provision of information related to the disease and its treatment, contents suitable to their socioeducational characteristics and needs, through individual educational strategies, visual and written, and suitable communication among professionals, patients, caregivers and services.OBJETIVO: Avaliar a alta hospitalar entre pacientes e cuidadores. MÉTODOS: Realizou-se uma revisão integrativa da literatura indexada nas bases de dados Pubmed, CINAHL e Lilacs de 2000 a 2005, focalizando a alta de pacientes adultos e idosos com problemas clínico-cirúrgicos, publicadas em língua inglesa ou portuguesa. RESULTADOS: A população consistiu de 54 publicações e a amostra foi de 23 artigos, que foram classificados em duas categorias temáticas: 13 focalizaram a efetividade e 10 a ineficácia do processo. CONSIDERAÇÕES FINAIS: Na visão dos sujeitos, a eficácia do planejamento da alta deve-se ao fornecimento de informações relacionadas à doença e tratamento, com conteúdos apropriados às suas características sócio-educacionais e necessidades, por meio de estratégias educacionais individuais, visuais e escritas, e comunicação adequada entre os profissionais, pacientes, cuidadores e serviços.OBJETIVO: Evaluar el alta hospitalario entre pacientes y cuidadores. MÉTODOS: Se llevó a cabo una revisión integrada de la literatura indexada en las bases de datos Pubmed, CINAHL y Lilacs del 2000 al 2005, enfocando el alta de pacientes adultos y ancianos con problemas clínico-quirúrgicos, publicadas en lengua inglesa o portuguesa. RESULTADOS: La población estuvo constituída de 54 publicaciones y la muestra fue de 23 artículos, clasificados en dos categorías temáticas: 13 enfocaban la efectividad y 10 la ineficacia del proceso. CONSIDERACIONES FINALES: En la visión de los sujetos, la eficacia de la planificación del alta se debe al ofrecimiento de informaciones relacionadas a la enfermedad y tratamiento, con contenidos apropiados a sus características socio-educativas y necesidades, por medio de estrategias educativas individuales, visuales y escritas, y comunicación adecuada entre los profesionales, pacientes, cuidadores y servicios

Neurotransmitter uptake of synaptic vesicles studied by X-ray diffraction

The size, polydispersity, and electron density profile of synaptic vesicles (SVs) can be studied by small-angle X-ray scattering (SAXS), i.e. by X-ray diffraction from purified SV suspensions in solution. Here we show that size and shape transformations, as they appear in the functional context of these important synaptic organelles, can also be monitored by SAXS. In particular, we have investigated the active uptake of neurotransmitters, and find a mean vesicle radius increase of about 12% after the uptake of glutamate, which indicates an unusually large extensibility of the vesicle surface, likely to be accompanied by conformational changes of membrane proteins and rearrangements of the bilayer. Changes in the electron density profile (EDP) give first indications for such a rearrangement. Details of the protein structure are screened, however, by SVs polydispersity. To overcome the limitations of large ensemble averages and heterogeneous structures, we therefore propose serial X-ray diffraction by single free electron laser pulses. Using simulated data for realistic parameters, we show that this is in principle feasible, and that even spatial distances between vesicle proteins could be assessed by this approach

Cross-linking mass spectrometry uncovers protein interactions and functional assemblies in synaptic vesicle membranes

Synaptic vesicles are storage organelles for neurotransmitters. They pass through a trafficking cycle and fuse with the pre-synaptic membrane when an action potential arrives at the nerve terminal. While molecular components and biophysical parameters of synaptic vesicles have been determined, our knowledge on the protein interactions in their membranes is limited. Here, we apply cross-linking mass spectrometry to study interactions of synaptic vesicle proteins in an unbiased approach without the need for specific antibodies or detergent-solubilisation. Our large-scale analysis delivers a protein network of vesicle sub-populations and functional assemblies including an active and an inactive conformation of the vesicular ATPase complex as well as non-conventional arrangements of the luminal loops of SV2A, Synaptophysin and structurally related proteins. Based on this network, we specifically target Synaptobrevin-2, which connects with many proteins, in different approaches. Our results allow distinction of interactions caused by ‘crowding’ in the vesicle membrane from stable interaction modules

In vitro fusion of single synaptic and dense core vesicles reproduces key physiological properties.

Regulated exocytosis of synaptic vesicles is substantially faster than of endocrine dense core vesicles despite similar molecular machineries. The reasons for this difference are unknown and could be due to different regulatory proteins, different spatial arrangements, different vesicle sizes, or other factors. To address these questions, we take a reconstitution approach and compare regulated SNARE-mediated fusion of purified synaptic and dense core chromaffin and insulin vesicles using a single vesicle-supported membrane fusion assay. In all cases, Munc18 and complexin are required to restrict fusion in the absence of calcium. Calcium triggers fusion of all docked vesicles. Munc13 (C1C2MUN domain) is required for synaptic and enhanced insulin vesicle fusion, but not for chromaffin vesicles, correlating inversely with the presence of CAPS protein on purified vesicles. Striking disparities in calcium-triggered fusion rates are observed, increasing with curvature with time constants 0.23 s (synaptic vesicles), 3.3 s (chromaffin vesicles), and 9.1 s (insulin vesicles) and correlating with rate differences in cells

Colocalization of different neurotransmitter transporters on synaptic vesicles is sparse except for VGLUT1 and ZnT3

Vesicular transporters (VTs) define the type of neurotransmitter that synaptic vesicles (SVs) store and release. While certain mammalian neurons release multiple transmitters, it is not clear whether the release occurs from the same or distinct vesicle pools at the synapse. Using quantitative single-vesicle imaging, we show that a vast majority of SVs in the rodent brain contain only one type of VT, indicating specificity for a single neurotransmitter. Interestingly, SVs containing dual transporters are highly diverse (27 types) but small in proportion (2% of all SVs), excluding the largest pool that carries VGLUT1 and ZnT3 (34%). Using VGLUT1-ZnT3 SVs, we demonstrate that the transporter colocalization influences the SV content and synaptic quantal size. Thus, the presence of diverse transporters on the same vesicle is bona fide, and depending on the VT types, this may act to regulate neurotransmitter type, content, and release in space and time

Caracterização dos efeitos do GMP sobre a memória de longa duração

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Antidepressant-like effects of chronic guanosine in the olfactory bulbectomy mouse model

Major depressive disorder (MDD) leads to pervasive changes in the health of afflicted patients. Despite advances in the understanding of MDD and its treatment, profound innovation is needed to develop fast-onset antidepressants with higher effectiveness. When acutely administered, the endogenous nucleoside guanosine (GUO) shows fast-onset antidepressant-like effects in several mouse models, including the olfactory bulbectomy (OBX) rodent model. OBX is advocated to possess translational value and be suitable to assess the time course of depressive-like behavior in rodents. This study aimed at investigating the long-term behavioral and neurochemical effects of GUO in a mouse model of depression induced by bilateral bulbectomy (OBX). Mice were submitted to OBX and, after 14 days of recovery, received daily (ip) administration of 7.5 mg/kg GUO or 40 mg/kg imipramine (IMI) for 45 days. GUO and IMI reversed the OBX-induced hyperlocomotion and recognition memory impairment, hippocampal BDNF increase, and redox imbalance (ROS, NO, and GSH levels). GUO also mitigated the OBX-induced hippocampal neuroinflammation (IL-1, IL-6, TNF-α, INF-γ, and IL-10). Brain microPET imaging ([18F]FDG) shows that GUO also prevented the OBX-induced increase in hippocampal FDG metabolism. These results provide additional evidence for GUO antidepressant-like effects, associated with beneficial neurochemical outcomes relevant to counteract depression