187 research outputs found

    Novel large-range mitochondrial dna deletions and fatal multisystemic disorder with prominent hepatopathy

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    Hepatic involvement in mitochondrial cytopathies rarely manifests in adulthood, but is a common feature in children. Multiple OXPHOS enzyme defects in children with liver involvement are often associated with dramatically reduced amounts of mtDNA. We investigated two novel large scale deletions in two infants with a multisystem disorder and prominent hepatopathy. Amount of mtDNA deletions and protein content were measured in different post-mortem tissues. The highest levels of deleted mtDNA were in liver, kidney, pancreas of both patients. Moreover, mtDNA deletions were detected in cultured skin fibroblasts in both patients and in blood of one during life. Biochemical analysis showed impairment of mainly complex I enzyme activity. Patients manifesting multisystem disorders in childhood may harbour rare mtDNA deletions in multiple tissues. For these patients, less invasive blood specimens or cultured fibroblasts can be used for molecular diagnosis. Our data further expand the array of deletions in the mitochondrial genomes in association with liver failure. Thus analysis of mtDNA should be considered in the diagnosis of childhood-onset hepatopathies

    Clinical-genetic features and peculiar muscle histopathology in infantile DNM1L-related mitochondrial epileptic encephalopathy

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    Mitochondria are highly dynamic organelles, undergoing continuous fission and fusion. The DNM1L gene encodes for the DRP1 protein, an evolutionary conserved member of the dynamin family, responsible for fission of mitochondria, and having a role in the division of peroxisomes, as well. DRP1 impairment is implicated in several neurological disorders and associated with either de novo dominant or compound heterozygous mutations. In five patients presenting with severe epileptic encephalopathy we identified 5 de novo dominant DNM1L variants, the pathogenicity of which was validated in a yeast model. Fluorescence microscopy revealed abnormally elongated mitochondria and aberrant peroxisomes in mutant fibroblasts, indicating impaired fission of these organelles. Moreover, a very peculiar finding in our cohort of patients was the presence, in muscle biopsy, of core like areas with oxidative enzyme alterations, suggesting an abnormal distribution of mitochondria in the muscle tissue

    Expanded phenotype of AARS1-related white matter disease.

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    Purpose Recent reports of individuals with cytoplasmic transfer RNA (tRNA) synthetase-related disorders have identified cases with phenotypic variability from the index presentations. We sought to assess phenotypic variability in individuals with AARS1-related disease. Methods A cross-sectional survey was performed on individuals with biallelic variants in AARS1. Clinical data, neuroimaging, and genetic testing results were reviewed. Alanyl tRNA synthetase (AlaRS) activity was measured in available fibroblasts. Results We identified 11 affected individuals. Two phenotypic presentations emerged, one with early infantile–onset disease resembling the index cases of AARS1-related epileptic encephalopathy with deficient myelination (n = 7). The second (n = 4) was a later-onset disorder, where disease onset occurred after the first year of life and was characterized on neuroimaging by a progressive posterior predominant leukoencephalopathy evolving to include the frontal white matter. AlaRS activity was significantly reduced in five affected individuals with both early infantile–onset and late-onset phenotypes. Conclusion We suggest that variants in AARS1 result in a broader clinical spectrum than previously appreciated. The predominant form results in early infantile–onset disease with epileptic encephalopathy and deficient myelination. However, a subgroup of affected individuals manifests with late-onset disease and similarly rapid progressive clinical decline. Longitudinal imaging and clinical follow-up will be valuable in understanding factors affecting disease progression and outcome

    Novel NDUFA12 variants are associated with isolated complex I defect and variable clinical manifestation.

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    Isolated biochemical deficiency of mitochondrial complex I is the most frequent signature amongst mitochondrial diseases and is associated with a wide variety of clinical symptoms. Leigh syndrome represents the most frequent neuroradiological finding in patients with complex I defect and >80 monogenic causes have been involved in the disease. In this report, we describe 7 patients from four unrelated families harbouring novel NDUFA12 variants, 6 of them presenting with Leigh syndrome. Molecular genetic characterization was performed using next generation sequencing combined with the Sanger method. Biochemical and protein studies were achieved by enzymatic activities, blue native gel electrophoresis and Western blotting. All patients displayed novel homozygous mutations in the NDUFA12 gene leading to the virtual absence of the corresponding protein. Surprisingly, despite in none of the analyzed patients NDUFA12 protein was detected, they present a different onset and clinical course of the disease. Our report expands the array of genetic alterations in NDUFA12 and underlines phenotype variability associated with NDUFA12 defect. This article is protected by copyright. All rights reserved

    Towards successful coordination of electronic health record based-referrals: a qualitative analysis

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    <p>Abstract</p> <p>Background</p> <p>Successful subspecialty referrals require considerable coordination and interactive communication among the primary care provider (PCP), the subspecialist, and the patient, which may be challenging in the outpatient setting. Even when referrals are facilitated by electronic health records (EHRs) (<it>i.e</it>., e-referrals), lapses in patient follow-up might occur. Although compelling reasons exist why referral coordination <it>should </it>be improved, little is known about which elements of the complex referral coordination process should be targeted for improvement. Using Okhuysen & Bechky's coordination framework, this paper aims to understand the barriers, facilitators, and suggestions for improving communication and coordination of EHR-based referrals in an integrated healthcare system.</p> <p>Methods</p> <p>We conducted a qualitative study to understand coordination breakdowns related to e-referrals in an integrated healthcare system and examined work-system factors that affect the timely receipt of subspecialty care. We conducted interviews with seven subject matter experts and six focus groups with a total of 30 PCPs and subspecialists at two tertiary care Department of Veterans Affairs (VA) medical centers. Using techniques from grounded theory and content analysis, we identified organizational themes that affected the referral process.</p> <p>Results</p> <p>Four themes emerged: lack of an institutional referral policy, lack of standardization in certain referral procedures, ambiguity in roles and responsibilities, and inadequate resources to adapt and respond to referral requests effectively. Marked differences in PCPs' and subspecialists' communication styles and individual mental models of the referral processes likely precluded the development of a <it>shared </it>mental model to facilitate coordination and successful referral completion. Notably, very few barriers related to the EHR were reported.</p> <p>Conclusions</p> <p>Despite facilitating information transfer between PCPs and subspecialists, e-referrals remain prone to coordination breakdowns. Clear referral policies, well-defined roles and responsibilities for key personnel, standardized procedures and communication protocols, and adequate human resources must be in place before implementing an EHR to facilitate referrals.</p

    Region-Specific Expression of Mitochondrial Complex I Genes during Murine Brain Development

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    Mutations in the nuclear encoded subunits of mitochondrial complex I (NADH:ubiquinone oxidoreductase) may cause circumscribed cerebral lesions ranging from degeneration of the striatal and brainstem gray matter (Leigh syndrome) to leukodystrophy. We hypothesized that such pattern of regional pathology might be due to local differences in the dependence on complex I function. Using in situ hybridization we investigated the relative expression of 33 nuclear encoded complex I subunits in different brain regions of the mouse at E11.5, E17.5, P1, P11, P28 and adult (12 weeks). With respect to timing and relative intensity of complex I gene expression we found a highly variant pattern in different regions during development. High average expression levels were detected in periods of intense neurogenesis. In cerebellar Purkinje and in hippocampal CA1/CA3 pyramidal neurons we found a second even higher peak during the period of synaptogenesis and maturation. The extraordinary dependence of these structures on complex I gene expression during synaptogenesis is in accord with our recent findings that gamma oscillations – known to be associated with higher cognitive functions of the mammalian brain – strongly depend on the complex I activity. However, with the exception of the mesencephalon, we detected only average complex I expression levels in the striatum and basal ganglia, which does not explain the exquisite vulnerability of these structures in mitochondrial disorders

    Organizing risk: organization and management theory for the risk society

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    Risk has become a crucial part of organizing, affecting a wide range of organizations in all sectors. We identify, review and integrate diverse literatures relevant to organizing risk, building on an existing framework that describes how risk is organized in three ‘modes’ – prospectively, in real-time, and retrospectively. We then identify three critical issues in the existing literature: its fragmented nature; its neglect of the tensions associated with each of the modes; and its tendency to assume that the meaning of an object in relation to risk is singular and stable. We provide a series of new insights with regard to each of these issues. First, we develop the concept of a risk cycle that shows how organizations engage with all three modes and transition between them over time. Second, we explain why the tensions have been largely ignored and show how studies using a risk work perspective can provide further insights into them. Third, we develop the concept of risk translation to highlight the ways in the meanings of risks can be transformed and to identify the political consequences of such translations. We conclude the paper with a research agenda to elaborate these insights and ideas further

    Identification of nursing assessment models/tools validated in clinical practice for use with diverse ethno-cultural groups: an integrative review of the literature

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    <p>Abstract</p> <p>Background</p> <p>High income nations are currently exhibiting increasing ethno-cultural diversity which may present challenges for nursing practice. We performed an integrative review of literature published in North America and Europe between 1990 and 2007, to map the state of knowledge and to identify nursing assessment tools/models which are have an associated research or empirical perspective in relation to ethno-cultural dimensions of nursing care.</p> <p>Methods</p> <p>Data was retrieved from a wide variety of sources, including key electronic bibliographic databases covering research in biomedical fields, nursing and allied health, and culture, e.g. CINAHL, MEDline, PUBmed, Cochrane library, PsycINFO, Web of Science, and HAPI. We used the Critical Appraisal Skills Programme tools for quality assessment. We applied Torraco's definition and method of an integrative review that aims to create new knowledge and perspectives on a given phenomena. To add methodological rigor with respect to the search strategy and other key review components we also used the principles established by the Centre for Reviews and Dissemination.</p> <p>Results</p> <p>Thirteen thousand and thirteen articles were retrieved, from which 53 full papers were assessed for inclusion. Eight papers met the inclusion criteria, describing research on a total of eight ethno-cultural assessment tools/models. The tools/models are described and synthesized.</p> <p>Conclusions</p> <p>While many ethno-cultural assessment tools exist to guide nursing practice, few are informed by research perspectives. An increased focus on the efficiency and effectiveness of health services, patient safety, and risk management, means that provision of culturally responsive and competent health services will inevitably become paramount.</p

    Modify the redefined: strategic human resource development maturity at a crossroads

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    This integrative literature review reports on strategic human resource development (SHRD) models that examine the strategic embeddedness of HRD (SHRD maturity) in organizations. A review and critique of all existing SHRD models is provided, exemplifying their limitations and building upon their strengths to inform a modified SHRD framework. The latter suggests an enhanced set of strategic components to assess SHRD maturity. This paper further outlines how SHRD aspirations can be practiced within complex, dynamic, and continually changing business and economic environments. The SHRD literature is advanced by new insights on how HRD scholars and practitioners could assess and enhance the maturity of their HRD interventions in the context of constantly changing (dynamic) environments. The modified SHRD framework further contributes to the academic literature with its enhanced set of strategic characteristics, as well as with its SHRD pointers, all of which can offer a better evaluation of SHRD maturity during periods of business and economic complexity and uncertainty

    Spiritual Care in General Practice : Rushing in or fearing to tread? An Integrative Review of Qualitative Literature

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    Acknowledgements Thanks to Jenny Jones, Stirling University, Rod Sampson and Melanie Bickerton, and Nicola Ring, University of Stirling. Funding A bursary from the University of Aberdeen was awarded. Ethical approval is not required. Open access via Springer CompactPeer reviewedPublisher PD
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