Quality of life in patients with seasonal affective disorder: summer vs winter scores.

OBJECTIVE: To compare perceived quality of life (QoL) in patients diagnosed with seasonal affective disorder (SAD) during the winter and summer months. METHODS: Twenty-six patients who were enrolled in an ongoing multicentre study in Canada completed 2 measures of QoL (the 20-item Medical Outcomes Study Short-Form General Health Survey [SF-20] and the Quality of Life Enjoyment and Satisfaction Questionnaire, [Q-LES-Q]) during the winter, when suffering from depression, and again during the summer months. RESULTS: Both general and health-related QoL scores were significantly improved in patients with SAD during the summer months, with scores for the most part falling within normal range. CONCLUSIONS: Perceived QoL in patients with SAD is markedly impaired during the winter months but shows a substantial rebound during the summer months. The findings of this study provide further evidence that SAD is a distinct diagnostic entity.     

Teaching ethics to paediatrics residents: the centrality of the therapeutic alliance

Context Previous research on ethical issues encountered by medical professionals in training and practice have presented the thematic content of the cases they encounter rather than the activities in which clinicians engage and in which they most often encounter ethical issues. We conducted a direct observation study of paediatrics residents and their preceptors seeing patients in an out‐patient general paediatrics clinic. Our objectives were to describe the everyday ethics‐related issues paediatrics residents encounter as they interact with patients. Our ultimate goal is to use this knowledge to enhance current efforts to teach ethics to paediatrics residents. Methods The study team directly observed paediatrics residents discussing patients with their faculty preceptors (19 half‐day sessions, 76 hours) in an out‐patient general paediatrics clinic located in an urban academic medical centre. Each interaction between resident and preceptor about a single patient was considered a case for further analysis. Results A total of 247 cases were recorded. Forty‐one of the cases were coded as having ethics‐related content. A constant comparative method of qualitative data analysis revealed that residents were most likely to encounter ethical issues when engaged in the following activities: (i) maintaining a therapeutic alliance with the caregiver (e.g. the parent); (ii) prioritising patient or family needs; (iii) adjusting to the power embodied by the role of doctors, and (iv) distinguishing suboptimal care from abuse or neglect. In addition, our findings indicate that it is through their efforts to maintain the therapeutic alliance with the caregivers of their patients that residents engage in and integrate three processes: developing their medical knowledge; adhering to professional norms, and balancing the power inherent in the doctor’s role with their responsibility to serve the patient’s interests. Conclusions Medical faculty tasked with teaching ethics to paediatrics residents can utilise the results of this project to better target and enhance their ethics education efforts directed at residents in the out‐patient setting. Future research could further examine and test these findings in other clinical settings (e.g. adult general medicine).     

Engineering angiogenesis following spinal cord injury: a coculture of neural progenitor and endothelial cells in a degradable polymer implant leads to an increase in vessel density and formation of the blood–spinal cord barrier

Angiogenesis precedes recovery following spinal cord injury and its extent correlates with neural regeneration, suggesting that angiogenesis may play a role in repair. An important precondition for studying the role of angiogenesis is the ability to induce it in a controlled manner. Previously, we showed that a coculture of endothelial cells (ECs) and neural progenitor cells (NPCs) promoted the formation of stable tubes in vitro and stable, functional vascular networks in vivo in a subcutaneous model. We sought to test whether a similar coculture would lead to the formation of stable functional vessels in the spinal cord following injury. We created microvascular networks in a biodegradable two-component implant system and tested the ability of the coculture or controls (lesion control, implant alone, implant + ECs or implant + NPCs) to promote angiogenesis in a rat hemisection model of spinal cord injury. The coculture implant led to a fourfold increase in functional vessels compared with the lesion control, implant alone or implant + NPCs groups and a twofold increase in functional vessels over the implant + ECs group. Furthermore, half of the vessels in the coculture implant exhibited positive staining for the endothelial barrier antigen, a marker for the formation of the blood–spinal cord barrier. No other groups have shown positive staining for the blood–spinal cord barrier in the injury epicenter. This work provides a novel method to induce angiogenesis following spinal cord injury and a foundation for studying its role in repair.     

Macrophage activation and Fcgamma receptor-mediated signaling do not require expression of the SLP-76 and SLP-65 adaptors

The Src-homology 2 domain-containing, leukocyte-specific phosphoprotein of 76 kDa (SLP-76) is a hematopoietic adaptor that plays a central role during immunoreceptor-mediated activation of T lymphocytes and mast cells and collagen receptor-induced activation of platelets. Despite similar levels of expression in macrophages, SLP-76 is not required for Fc receptor for immunoglobulin G (IgG; FcgammaR)-mediated activation. We hypothesized that the related adaptor SLP-65, which is also expressed in macrophages, may compensate for the loss of SLP-76 during FcgammaR-mediated signaling and functional events. To address this hypothesis, we examined bone marrow-derived macrophages (BMM) from wild-type (WT) mice or mice lacking both of these adaptors. Contrary to our expectations, SLP-76(-/-) SLP-65(-/-) BMM demonstrated normal FcgammaR-mediated activation, including internalization of Ig-coated sheep red blood cells and production of reactive oxygen intermediates. FcgammaR-induced biochemical events were normal in SLP-76(-/-) SLP-65(-/-) BMM, including phosphorylation of phospholipase C and the extracellular signaling-regulated kinases 1 and 2. To determine whether macrophages functioned normally in vivo, we infected WT and SLP-76(-/-) SLP-65(-/-) mice with sublethal doses of Listeria monocytogenes (LM), a bacterium against which the initial host defense is provided by activated macrophages. WT and SLP-76(-/-) SLP-65(-/-) mice survived acute, low-dose infection and showed no difference in the number of liver or spleen LM colony-forming units, a measure of the total body burden of this organism. Taken together, these data suggest that neither SLP-76 nor SLP-65 is required during FcgammaR-dependent signaling and functional events in macrophages.     

Real-time imaging of Rab3a and Rab5a reveals differential roles in presynaptic function

We investigated the roles of two Rab-family proteins, Rab3a and Rab5a, in hippocampal synaptic transmission using real-time fluorescence imaging. During synaptic activity, Rab3a dissociated from synaptic vesicles and dispersed into neighbouring axonal regions. Dispersion required calcium-dependent exocytosis and was complete before the entire vesicle pool turned over. In contrast, even prolonged synaptic activity produced limited dispersion of Rab5a. A GTPase-deficient mutant, Rab3a (Q81L), dispersed more slowly than wild-type Rab3a, and decreased the rate of exocytosis and the size of the recycling pool of vesicles. While overexpression of Rab3a did not affect vesicle recycling, overexpression of Rab5a reduced the recycling pool size by 50%. We propose that while Rab3a preferentially associates with recycling synaptic vesicles and modulates their trafficking, Rab5a is largely excluded from recycling vesicles.