21 research outputs found

    Diagnosing and managing diabetic somatic and autonomic neuropathy

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    The diagnosis and management of diabetic neuropathy can be a major challenge. Late diagnosis contributes to significant morbidity in the form of painful diabetic neuropathy, foot ulceration, amputation, and increased mortality. Both hyperglycaemia and cardiovascular risk factors are implicated in the development of somatic and autonomic neuropathy and an improvement in these risk factors can reduce their rate of development and progression. There are currently no US Food and Drug Administration (FDA)-approved disease-modifying treatments for either somatic or autonomic neuropathy, as a consequence of multiple failed phase III clinical trials. While this may be partly attributed to premature translation, there are major shortcomings in trial design and outcome measures. There are a limited number of partially effective FDA-approved treatments for the symptomatic relief of painful diabetic neuropathy and autonomic neuropathy

    Enzymatic Mechanisms Involved in Evasion of Fungi to the Oxidative Stress: Focus on Scedosporium apiospermum

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    The airways of patients with cystic fibrosis (CF) are frequently colonized by various filamentous fungi, mainly Aspergillus fumigatus and Scedosporium species. To establish within the respiratory tract and cause an infection, these opportunistic fungi express pathogenic factors allowing adherence to the host tissues, uptake of extracellular iron, or evasion to the host immune response. During the colonization process, inhaled conidia and the subsequent hyphae are exposed to reactive oxygen species (ROS) and reactive nitrogen species (RNS) released by phagocytic cells, which cause in the fungal cells an oxidative stress and a nitrosative stress, respectively. To cope with these constraints, fungal pathogens have developed various mechanisms that protect the fungus against ROS and RNS, including enzymatic antioxidant systems. In this review, we summarize the different works performed on ROS- and RNS-detoxifying enzymes in fungi commonly encountered in the airways of CF patients and highlight their role in pathogenesis of the airway colonization or respiratory infections. The potential of these enzymes as serodiagnostic tools is also emphasized. In addition, taking advantage of the recent availability of the whole genome sequence of S. apiospermum, we identified the various genes encoding ROS- and RNS-detoxifying enzymes, which pave the way for future investigations on the role of these enzymes in pathogenesis of these emerging species since they may constitute new therapeutics targets

    Right ectopic paraesophageal parathyroid adenoma with refractory hypercalcemia in pregnancy : A case report and review of the literature

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    Introduction: Ectopic parathyroid adenoma is rare during pregnancy but poses multiple challenges in treatment. It presents as primary hyperparathyroidism which leads to symptoms and complications of hypercalcemia in both the mother and fetus. Presentation of case: A 38-year-old Sudanese female presented with diffuse bone pain and polyuria. Laboratory investigations revealed elevated serum calcium and parathyroid hormone. Ultrasound of the neck did not show any abnormal lesion, however 99mTc-sestamibi scan showed a right sided parathyroid adenoma, and an earlier CT scan showed the adenoma to be in an ectopic paraesophageal position. Focused surgical neck exploration was done, and the ectopic parathyroid adenoma was excised. Discussion: Preoperative localization of the ectopic parathyroid adenoma allows for a focused surgical procedure. Ultrasound is the safest during pregnancy, but 99mTc-sestamibi and CT scan may be necessary if ultrasound or initial bilateral neck exploration do not detect any adenoma. Mild elevations in maternal serum calcium can have detrimental effects on the fetus which suggests that a surgical approach may be necessary in the majority of cases. Conclusions: Ectopic parathyroid adenoma is rare during pregnancy and is detrimental to both the mother and fetus. Preoperative localization allows for a focused surgery which is a definitive treatment and can safely be performed during the 2nd trimester of pregnancy. CC BY-NC-ND 4.0</p

    Loss of corneal nerves and brain volume in mild cognitive impairment and dementia

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    Abstract Introduction This study compared the capability of corneal confocal microscopy (CCM) with magnetic resonance imaging (MRI) brain volumetry for the diagnosis of mild cognitive impairment (MCI) and dementia. Methods In this cross‐sectional study, participants with no cognitive impairment (NCI), MCI, and dementia underwent assessment of Montreal Cognitive Assessment (MoCA), MRI brain volumetry, and CCM. Results Two hundred eight participants with NCI (n = 42), MCI (n = 98), and dementia (n = 68) of comparable age and gender were studied. For MCI, the area under the curve (AUC) of CCM (76% to 81%), was higher than brain volumetry (52% to 70%). For dementia, the AUC of CCM (77% to 85%), was comparable to brain volumetry (69% to 93%). Corneal nerve fiber density, length, branch density, whole brain, hippocampus, cortical gray matter, thalamus, amygdala, and ventricle volumes were associated with cognitive impairment after adjustment for confounders (All P’s < .01). Discussion The diagnostic capability of CCM compared to brain volumetry is higher for identifying MCI and comparable for dementia, and abnormalities in both modalities are associated with cognitive impairment

    Effect of Growth Rate on the Microstructure and Microhardness in a Directionally Solidified Al-Zn-Mg Alloy

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    The Al-5.5Zn-2.5Mg (wt pct) ternary alloy was prepared using a vacuum melting furnace and a casting furnace. Five samples were directionally solidified upwards at a constant temperature gradient (G = 5.5 K/mm) under different growth rates (V = 8.3-165 mu m/s) in a Bridgman-type directional solidification furnace. The primary dendrite arm spacing, lambda (1), secondary dendrite arm spacing, lambda (2), and microhardness, HV, of the samples were measured. The effects of V on lambda (1), lambda (2) and HV properties of the Al-Zn-Mg alloy were studied by microstructure analysis and mechanical characterization. Microstructure characterization of the alloys was carried out using optical microscopy, scanning electron microscopy, wavelength-dispersive X-ray fluorescence spectrometry, and energy dispersive X-ray spectroscopy. From the experimental results, it is found that the lambda (1), lambda (2) values decrease, but HV values increase with the increase in V, and HV values decrease with the increase in lambda (1) and lambda (2). Dependencies of dendritic spacing and microhardness on the growth rate were determined using linear regression analysis. The growth rate, microstructure, and Hall-Petch-type relationships obtained in this work have been compared with the results of previous studies

    Effects of Growth Rates and Compositions on Dendrite Arm Spacings in Directionally Solidified Al-Zn Alloys

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    Dendritic spacing can affect microsegregation profiles and also the formation of secondary phases within interdendritic regions, which influences the mechanical properties of cast structures. To understand dendritic spacings, it is important to understand the effects of growth rate and composition on primary dendrite arm spacing (lambda(1)) and secondary dendrite arm spacing (lambda(2)). In this study, aluminum alloys with concentrations of (1, 3, and 5 wt pct) Zn were directionally solidified upwards using a Bridgman-type directional solidification apparatus under a constant temperature gradient (10.3 K/mm), resulting in a wide range of growth rates (8.3-165.0 mu m/s). Microstructural parameters, lambda(1) and lambda(2) were measured and expressed as functions of growth rate and composition using a linear regression analysis method. The values of lambda(1) and lambda(2) decreased with increasing growth rates. However, the values of lambda(1) increased with increasing concentration of Zn in the Al-Zn alloy, but the values of lambda(2) decreased systematically with an increased Zn concentration. In addition, a transition from a cellular to a dendritic structure was observed at a relatively low growth rate (16.5 mu m/s) in this study of binary alloys. The experimental results were compared with predictive theoretical models as well as experimental works for dendritic spacing. (C) The Minerals, Metals & Materials Society and ASM International 201
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