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Abstract: Osteoporosis is a degenerative bone disease that causes significant morbidity and mortality in multiple sclerosis (MS) patients; the pathogenesis of this disease being poorly understood in the context of MS. Osteoporosis is seen more frequently in MS patients than in healthy controls matched for age and sex. Extensively studied factors, including impaired ambulation and the use of steroids, do not appear to completely account for the phenomenon. This review summarizes common risk factors, physiologic and genetic, that may contribute to the etiology and progression of osteoporosis in MS patients as well as providing insight into nervous system control of bone metabolism and homeostasis. [Copyright &y& Elsevier]

Abstract: Multiple sclerosis is an autoimmune demyelinating disorder of the central nervous system. Its etiology continues to be elucidated. The debate about the environmental impact on the disease etiology and progression has focused on sun light exposure in the recent past, but mainly as it applies to vitamin D and its derivatives. This paper will discuss how sunlight stimulus may effect neuronal and microglial antigenic presentation based on sunlight-dependent neuronal activity, as well as how sunlight may alter the amount of vitamin A and melatonin levels during immune development in the central nervous system. Changes in the number of antigens presented to lymphocytes by antigen-presenting cells for self-selective removal during immune development could therefore alter the number of circulating self-recognizing B and T-lymphocytes. This situation would increase susceptibility to a significantly greater number of self-antigens, and lead to autoimmune disorders such as multiple sclerosis. [Copyright &y& Elsevier]

Laboratory factors associated with hemorrhagic conversion (HC) after Intravenous thrombolysis with rtPA (IVT) for Acute Ischemic Stroke (AIS) remain nebulous despite advances in our knowledge of AIS. This study aimed to investigate the laboratory factors predisposing to HC in AIS patients receiving IVT. We retrospectively reviewed the medical records of patients who received IV tPA for AIS at our comprehensive stroke center over a 9.6-year period. Besides age, gender, NIHSS, history of diabetes mellitus (DM), history of atrial fibrillation (Afib), we gathered their laboratory data including International Normalized Ratio (INR), lipid panel, serum albumin, serum creatinine, hemoglobin A1c (HbA1c), and admission blood glucose. Post-thrombolysis brain imagings were reviewed to evaluate for symptomatic ICH (sICH). The mean values of above mentioned laboratory data were compared between the group with sICH and patients with no sICH. Univariate and multivariate logistic regression were performed to evaluate the association of the laboratory findings with presence of sICH. sICH was defined as ICH causing an increase in NIHSS ≥4. Of the 794 subjects in this study 51 (6.4%) had sICH. In the univariate analysis, patients who developed sICH had significantly higher NIHSS on admission (14.2 ± 5.4 vs 11.2 ± 6.5, p <.001), LDL-cholesterol (113.3 mg/dl ±36.9 vs. 101.8 mg/dl ± 38.2, p =.032), HbA1c (6.9% ± 2.3 vs. 6.1 ± 1.3, p =.003) and lower levels of Albumin (3.5 g/dl ±0.4 vs. 3.9 g/dl ± 0.5, p <.001). Furthermore, a higher prevalence of history of DM (45% vs. 21.6%, p =.020) and Afib (25.4% vs. 10.4%, p =.028) was found in subjects who developed sICH. There were no significant group differences regarding age, sex, total cholesterol, blood glucose on admission, serum creatinine or INR levels (p >.05). After adjusting for multiple covariates, lower Albumin level and and higher HbA1c were significantly associated with an increased risk for sICH development (p <.05). Chances of sICH increased by 33% for every 1 g/dl below a normal albumin level of 4.0 g/dl (p <.05). Lower endogenous albumin level and higher HbA1c have shown to predispose to a higher risk of sICH after IVT for AIS and might be good predictors of sICH post IVT. • We studied the laboratory factors predisposing to hemorrhagic conversion (HC) in acute ischemic stroke (AIS) patients receiving Intravenous thrombolysis (IVT). • Lower Albumin level and higher HbA1c were significantly associated with an increased risk of symptomatic HC (sHC). • Chances of sHC increased by 33% for every 1 g/dl below a normal albumin level of 4.0 g/dl (p <.05). [ABSTRACT FROM AUTHOR]

A comprehensive investigation of the structural, vibrational, electronic, and elastic characteristics of four hexagonal bilayer chromium pnictogens (CrX; X = N, P, As, Sb) materials has been conducted using first-principles calculations based on density functional theory (DFT). The phonon dispersion investigations demonstrate the dynamic stability of the examined hexagonal bilayers belonging to pnictogens group, in their planar structure. According to our phonon dispersion analysis, only two materials, CrN/CrN and CrP/CrP, are found to be dynamically stable, while the other two, CrAs/CrAs and CrSb/CrSb are reveal to be dynamically unstable. The band structure calculations carried out utilizing HSE06 hybrid functionals reveals the metallic nature of bilayer chromium pnictogens. In all CrX materials, the highest work function we observed for CrN/CrN material as 5.17 eV. Along the armchair direction in CrN/CrN compounds, highest elastic constants (C 2D) is obtained among all CrX compounds, measured as 192.47 Nm−1 for electron carriers. In addition to examining the phonon dispersion, we also assessed their mechanical stability by the computation of elastic characteristics. Our calculated elastic parameters and polar diagrams of Young's modulus and Poisson's ratio indicate the mechanical stability of all the systems under consideration. To further our understanding of CrX compounds, we also acquired data on their deformation potential for electron carriers in both armchair and zigzag orientations. This work unequivocally demonstrates the advantages of CrX bilayers as potential materials for upcoming robust conducting devices and also possible applications for a 2D metallic material. • Structural, vibrational, electronic and elastic properties of hexagonal bilayer chromium pnictogens are investigated. • Analysis of electronic properties reveals metallic behavior of CrX (X = N, P, As, Sb). • Investigation of elastic properties of all CrX materials implying their mechanical stability. • Present work may certainly be a motivation to explore these materials for future robust conductors. [ABSTRACT FROM AUTHOR]