787 research outputs found

    In vivo impact of presynaptic calcium channel dysfunction on motor axons in episodic ataxia type 2

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    Ion channel dysfunction causes a range of neurological disorders by altering transmembrane ion fluxes, neuronal or muscle excitability, and neurotransmitter release. Genetic neuronal channelopathies affecting peripheral axons provide a unique opportunity to examine the impact of dysfunction of a single channel subtype in detail in vivo. Episodic ataxia type 2 is caused by mutations in CACNA1A, which encodes the pore-forming subunit of the neuronal voltage-gated calcium channel Cav2.1. In peripheral motor axons, this channel is highly expressed at the presynaptic neuromuscular junction where it contributes to action potential-evoked neurotransmitter release, but it is not expressed mid-axon or thought to contribute to action potential generation. Eight patients from five families with genetically confirmed episodic ataxia type 2 underwent neurophysiological assessment to determine whether axonal excitability was normal and, if not, whether changes could be explained by Cav2.1 dysfunction. New mutations in the CACNA1A gene were identified in two families. Nerve conduction studies were normal, but increased jitter in single-fibre EMG studies indicated unstable neuromuscular transmission in two patients. Excitability properties of median motor axons were compared with those in 30 age-matched healthy control subjects. All patients had similar excitability abnormalities, including a high electrical threshold and increased responses to hyperpolarizing (P < 0.00007) and depolarizing currents (P < 0.001) in threshold electrotonus. In the recovery cycle, refractoriness (P < 0.0002) and superexcitability (P < 0.006) were increased. Cav2.1 dysfunction in episodic ataxia type 2 thus has unexpected effects on axon excitability, which may reflect an indirect effect of abnormal calcium current fluxes during development

    Clinical, genetic, neurophysiological and functional study of new mutations in episodic ataxia type 1.

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    Heterozygous mutations in KCNA1 cause episodic ataxia type 1 (EA1), an ion channel disorder characterised by brief paroxysms of cerebellar dysfunction and persistent neuromyotonia. This paper describes four previously unreported families with EA1, with the aim of understanding the phenotypic spectrum associated with different mutations

    Bilateral congenital alveolar synechiae—a rare cause of trismus

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    Health-related Quality of Life in Patients With Nonalcoholic Fatty Liver Disease: A Prospective Multi-center UK Study

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    BACKGROUND & AIMS: It is unclear whether health-related quality of life (HRQoL) is impaired in patients with nonalcoholic fatty liver disease (NAFLD) without advanced fibrosis and how this compares with the general population. We aimed to assess HRQoL in patients with NAFLD in comparison to the general population and any associations of fibrosis severity and metabolic comorbidities with impairments in HRQoL. METHODS: We prospectively enrolled 513 consecutive patients with NAFLD who completed the EuroQol 5-dimensional questionnaire (EQ-5D) and Chronic Liver Disease Questionnaires (CLDQ). Demographic and clinical information, liver biopsy results, and/or liver stiffness (LS) by transient elastography were recorded. A general population sub-cohort of the Health Survey for England 2018 was used as a comparator (n = 5483), and a 1:1 propensity-score (PS) matching was performed, according to age, sex, body mass index, and type 2 diabetes mellitus (T2DM). RESULTS: EQ-5D-5L utility was significantly lower in 466 PS-matched patients with NAFLD compared with PS-matched controls (0.77 ± 0.27 vs 0.84 ± 0.19; P < .001), even in those without advanced fibrosis (F ≤2 or LS <8kPa) (0.80 ± 0.24 vs 0.84 ± 0.19; P = .024). HRQoL measures (EQ-5D-5L, EQ-VAS, CLDQ) did not differ between patients with NAFLD with and without advanced fibrosis. LS was independently associated with lower EQ-5D-5L in all patients with NAFLD but not in those without advanced fibrosis. In the latter, lower EQ-5D-5L was associated with female sex, T2DM, and depression. CONCLUSIONS: Patients with NAFLD, even those without advanced fibrosis, have worse HRQoL compared with the general population. In patients with NAFLD without advanced fibrosis, HRQoL is independently associated with non-liver comorbidities but not LS. Multi-disciplinary management is therefore required in NAFLD, irrespective of fibrosis severity

    Depression in older adults: prevalence and risk factors in a primary health care sample

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    BACKGROUND: Depression in the geriatric population has been identified as a significant problem in view of the associated negative outcomes regarding poor functioning, increased perception of poor health and increased utilisation of medical services. Significantly associated with increased morbidity and mortality, depression has been found to be an independent cause of disability as well as adding to disability due to primary physical illnesses. Early identification and treatment of depression reduces medical costs and lessens caregiver burden. Epidemiological data and prevalence rates of geriatric depression in Africa are limited, although such data are vital to mobilise and plan government mental health initiatives aimed at screening and early intervention. OBJECTIVE: To determine the prevalence of depression and associated clinical and socio-demographic factors amongst older adult patients attending a primary health care clinic in the Ethekwini District in Kwa-Zulu Natal, South Africa. METHODS: The 15-item Geriatric Depression Scale and a socio-demographic questionnaire were administered in English to 255 geriatric outpatients, randomly selected, at a local community clinic in Durban. DATA ANALYSIS: Data were analysed using SPSS version 23®. Descriptive statistics were used to summarise the sample demographics and response rate and non-parametric statistics were used to test for associations and differences. RESULTS: A Cronbach’s alpha for the GDS was calculated (p = 0.793). Some 40% of participants screened positive for depression. Female gender, widowhood and a negative subjective health status rating were significantly associated with depression and marriage appeared to be protective (p < 0.001). Participants with a poor subjective health rating were 21 times more likely to be depressed and widowhood conferred an almost fourfold increased risk of being depressed, with widows at greater risk than widowers. No association between depression and specific medical conditions was identified. CONCLUSION: There is a high rate of undetected depression among the elderly attending a local primary health care clinic with widowhood and poor subjective health being strong predictors of mood disorders. The findings warrant replication in bigger samples.DHE

    Treatments for alopecia areata: a network meta-analysis

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    Acknowledgement: “This Protocol of a Cochrane Review was published in the Cochrane Database of Systematic Reviews 2020, Issue 9. Cochrane Protocols and Reviews are regularly updated as new evidence emerges and in response to feedback, and the Cochrane Database of Systematic Reviews should be consulted for the most recent version of the Protocol.'Copyright © 2020 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd. Objectives: This is a protocol for a Cochrane Review (intervention). The objectives are as follows:. To assess the comparative effectiveness and safety of interventions used in the management of alopecia areata (AA), including patchy alopecia (PA), alopecia totalis (AT) and alopecia universalis (AU). To establish rankings of the available treatments for AA, based on their effectiveness and safety (primary outcomes), through a network meta-analysis

    Using honey to heal diabetic foot ulcers

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    Diabetic ulcers seem to be arrested in the inflammatory/proliferative stage of the healing process, allowing infection and inflammation to preclude healing. Antibiotic-resistant bacteria have become a major cause of infections, including diabetic foot infections. It is proposed here that the modern developments of an ancient and traditional treatment for wounds, dressing them with honey, provide the solution to the problem of getting diabetic ulcers to move on from the arrested state of healing. Honeys selected to have a high level of antibacterial activity have been shown to be very effective against antibiotic-resistant strains of bacteria in laboratory and clinical studies. The potent anti-inflammatory action of honey is also likely to play an important part in overcoming the impediment to healing that inflammation causes in diabetic ulcers, as is the antioxidant activity of honey. The action of honey in promotion of tissue regeneration through stimulation of angiogenesis and the growth of fibroblasts and epithelial cells, and its insulin-mimetic effect, would also be of benefit in stimulating the healing of diabetic ulcers. The availability of honey-impregnated dressings which conveniently hold honey in place on ulcers has provided a means of rapidly debriding ulcers and removing the bacterial burden so that good healing rates can be achieved with neuropathic ulcers. With ischemic ulcers, where healing cannot occur because of lack of tissue viability, these honey dressings keep the ulcers clean and prevent infection occurring

    Sialic Acid Glycobiology Unveils Trypanosoma cruzi Trypomastigote Membrane Physiology.

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    Trypanosoma cruzi, the flagellate protozoan agent of Chagas disease or American trypanosomiasis, is unable to synthesize sialic acids de novo. Mucins and trans-sialidase (TS) are substrate and enzyme, respectively, of the glycobiological system that scavenges sialic acid from the host in a crucial interplay for T. cruzi life cycle. The acquisition of the sialyl residue allows the parasite to avoid lysis by serum factors and to interact with the host cell. A major drawback to studying the sialylation kinetics and turnover of the trypomastigote glycoconjugates is the difficulty to identify and follow the recently acquired sialyl residues. To tackle this issue, we followed an unnatural sugar approach as bioorthogonal chemical reporters, where the use of azidosialyl residues allowed identifying the acquired sugar. Advanced microscopy techniques, together with biochemical methods, were used to study the trypomastigote membrane from its glycobiological perspective. Main sialyl acceptors were identified as mucins by biochemical procedures and protein markers. Together with determining their shedding and turnover rates, we also report that several membrane proteins, including TS and its substrates, both glycosylphosphatidylinositol-anchored proteins, are separately distributed on parasite surface and contained in different and highly stable membrane microdomains. Notably, labeling for α(1,3)Galactosyl residues only partially colocalize with sialylated mucins, indicating that two species of glycosylated mucins do exist, which are segregated at the parasite surface. Moreover, sialylated mucins were included in lipid-raft-domains, whereas TS molecules are not. The location of the surface-anchored TS resulted too far off as to be capable to sialylate mucins, a role played by the shed TS instead. Phosphatidylinositol-phospholipase-C activity is actually not present in trypomastigotes. Therefore, shedding of TS occurs via microvesicles instead of as a fully soluble form
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