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Few studies have examined the views of policy makers regarding the impact of mental health stigma on the development and implementation of mental health policies. This study aimed to address this knowledge gap by exploring policymakers’ and policy advisors’ perspectives regarding the impact of mental health stigma on the development and implementation of mental health programmes, strategies, and services in Singapore. In all 13 participants were recruited for the study comprising practicing policymakers, senior staff of organisations involved in implementing the various mental health programmes, and policy advisors. Data was collected through semi-structured interviews, which were transcribed verbatim and analysed using reflexive thematic analysis. Data analysis revealed three superordinate themes related to challenges experienced by the policymakers/advisors when dealing with mental health policy and implementation of programmes. These themes included stigma as a barrier to mental health treatment, community-level barriers to mental health recovery, and mental health being a neglected need. Policymakers/advisors demonstrated an in-depth and nuanced understanding of the barriers (consequent to stigma) to mental healthcare delivery and access. Policymakers/advisors were able to associate the themes related to the stigma towards mental illness with help-seeking barriers based on personal experiences, knowledge, and insight gained through the implementation of mental health programmes and initiatives.

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Normal cardiac excitation involves orderly conduction of electrical activation and recovery dependent upon surface membrane, voltage‐gated, sodium (Na+) channel α‐subunits (Nav1.5). We summarize experimental studies of physiological and clinical consequences of loss‐of‐function Na+ channel mutations. Of these conditions, Brugada syndrome (BrS) and progressive cardiac conduction defect (PCCD) are associated with sudden, often fatal, ventricular tachycardia (VT) or fibrillation. Mouse Scn5a+/? hearts replicate important clinical phenotypes modelling these human conditions. The arrhythmic phenotype is associated not only with the primary biophysical change but also with additional, anatomical abnormalities, in turn dependent upon age and sex, each themselves exerting arrhythmic effects. Available evidence suggests a unified binary scheme for the development of arrhythmia in both BrS and PCCD. Previous biophysical studies suggested that Nav1.5 deficiency produces a background electrophysiological defect compromising conduction, thereby producing an arrhythmic substrate unmasked by flecainide or ajmaline challenge. More recent reports further suggest a progressive decline in conduction velocity and increase in its dispersion particularly in ageing male Nav1.5 haploinsufficient compared to WT hearts. This appears to involve a selective appearance of slow conduction at the expense of rapidly conducting pathways with changes in their frequency distributions. These changes were related to increased cardiac fibrosis. It is thus the combination of the structural and biophysical changes both accentuating arrhythmic substrate that may produce arrhythmic tendency. This binary scheme explains the combined requirement for separate, biophysical and structural changes, particularly occurring in ageing Nav1.5 haploinsufficient males in producing clinical arrhythmia.  相似文献   
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OBJECTIVE: To compare biomechanical strength of deep-frozen versus lyophilized large cortical allografts. DESIGN: In vivo transplantation studies performed in tibia of adult cats using 4 cm deep-frozen and lyophilized, gamma-irradiated allografts to bridge large cortical defect model. BACKGROUND: Bridging large cortical bone defect is a challenging problem. Options include autografts, allografts, bioceramics and prostheses. Allografts provide a suitable option. METHODS: Forty mature cats were used. A large defect (4 cm) was created in mid-diaphysis of right tibia. In 16 cats, cortical defect was reconstructed using deep-frozen allografts (-80 degrees C) with intra-medullary rodding. In another 16 cats, lyophilized, gamma-irradiated allografts were used. Observation periods include 8, 12, 16 and 24 weeks. The specimens were procured together with unoperated legs as controls. Mechanical testing was performed using a materials testing machine with torsion test device of up to 500 Nm at speed of 0.18 rpm. Parameters studied included maximum torque, torsional stiffness and energy of absorption. RESULTS: Deep-frozen allografts did not reach 100% strength, achieving only 64% at 6 months. In marked contrast, lyophilized allografts were significantly weaker with only 12% maximum torque strength at 6 months. Lyophilized allografts were significantly weaker than deep-frozen allografts in all observation periods (p < 0.05). CONCLUSION: Deep-frozen allografts did not reach 100% normal strength and were significantly weaker than non-vascularised autografts. Lyophilized allografts were significantly weaker than deep-frozen allografts. RELEVANCE: For the reconstruction of massive cortical bone defects, only deep-frozen cortical allografts should be used. Lyophilized allografts are not suitable.  相似文献   
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