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Age-Specific Cutoff Scores on a T1-Weighted Axial Medial Temporal-Lobe Atrophy Visual Rating Scale in Alzheimer's Disease Using Clinical Research Center for Dementia of South Korea Data
No full textBackground and Purpose Visual assessment of medial temporal-lobe atrophy (MTA) has been quick, reliable, and easy to apply in routine clinical practice. However, one of the limitations in visual assessments of MTA is the lack of widely accepted age-adjusted norms and cutoff scores for MTA for a diagnosis of Alzheimer's disease (AD). This study aimed to determine the optimal cutoff score on a T1-weighted axial MTA Visual Rating Scale (VRS) for differentiating patients with AD from cognitively normal elderly people. Methods The 3,430 recruited subjects comprising 1,427 with no cognitive impairment (NC) and 2003 AD patients were divided into age ranges of 50-59, 60-69, 70-79, and 80-89 years. Of these, 446 participants (218 in the NC group and 228 in the AD group) were chosen by random sampling for inclusion in this study. Each decade age group included 57 individuals, with the exception of 47 subjects being included in the 80- to 89-year NC group. The scores on the T1-weighted axial MTA VRS were graded by two neurologists. The cutoff values were evaluated from the area under the receiver operating characteristic curve. Results The optimal axial MTA VRS cutoff score from discriminating AD from NC increased with age: it was >= as >= 1, >= 2, and >= 3 in subjects aged 50-59, 60-69, 70-79, and 80-89 years, respectively (all p<0.001). Conclusions These results show that the optimal cutoff score on the axial MTA VRS for diagnosing of AD differed according to the decade age group. This information could be of practical usefulness in the clinical setting
The J-shape association of serum total IgE levels with age-related cataract
No full text● AIM: To address the association between serum total IgE levels and age-related cataract in adults. ● METHODS: The study participants consisted of 1052 adults aged 40y or older in the Korean National Health and Nutrition Examination Survey 2010. We performed multivariable logistic regression analyses using the quartile cut-points of total IgE levels. ● RESULTS: The odds ratios (ORs) for nuclear and any cataract with ≥267 kU/L of serum IgE levels were 1.75 [95% confidence intervals (CI), 1.04-2.96] and 2.00 (95%CI, 1.22-3.27), respectively, comparing to 35-87 kU/L. Interestingly, participants with ≤35 kU/L of IgE levels (OR, 1.67; 95%CI, 1.02-2.72) also had higher risk for any cataract than those with 35-87 kU/L. The risk for any cataract (OR, 1.48; 95%CI, 1.03-2.13) was higher in participants with high total IgE levels (>150 kU/L), comparing to normal participants. ● CONCLUSION: Our findings indicate a J-shaped relationship between serum IgE levels and age-related cataract. © 2018, International Journal of Ophthalmology (c/o Editorial Office). All rights reserved
Damage propagation from component level to system level in the electricity sector
No full textIn the aftermath of an earthquake, the electric power supply system may have a reduced ability to maintain its intended function, leading to service disruptions of other interdependent facilities until the electricity sector gets restored. In order to analyze such extra functionality losses, the authors have developed an agent-based inoperability input-output model with a focus on damage propagation from a component level to a system level in the electricity sector. In addition, this research presents the probabilistic matrix for the quantification of correlation coefficients between two connected electricity sector components (e.g., power generator and deliverer) and uses these coefficients to identify critical components from a perspective of the network's reliability. The developed model thus allows us to understand how a degradation of component affects the functionality of the whole electricity sector. To demonstrate the model's analytic capability, this research conducted case simulations using the data from 2011 Tohoku earthquake. The simulation results show that the impact of seismic damage in a network is generally underestimated because there is unforeseen damage propagation from the component to the system level. Moreover, the results demonstrate that demand-side efforts to conserve electricity usage and restoration priority setting in accordance with component criticality are crucial to ensure community resilience in case of disaster. © 2018 American Society of Civil Engineers
Tonsil-derived mesenchymal stem cell-embedded in situ crosslinkable gelatin hydrogel therapy recovers postmenopausal osteoporosis through bone regeneration
No full textWe investigated therapeutic potential of human tonsil-derived mesenchymal stem cells (TMSC) subcutaneously delivered to ovariectomized (OVX) mice for developing more safe and effective therapy for osteoporosis. TMSC were isolated from tonsil tissues of children undergoing tonsillectomy, and TMSC-embedded in situ crosslinkable gelatin-hydroxyphenyl propionic acid hydrogel (TMSC-GHH) or TMSC alone were delivered subcutaneously to the dorsa of OVX mice. After 3 months, three-dimensionally reconstructed micro-computed tomographic images revealed better recovery of the femoral heads in OVX mice treated with TMSC-GHH. Serum osteocalcin and alkaline phosphatase were also recovered, indicating bone formation only in TMSC-GHH-treated mice, and absence in hypercalcemia or other severe macroscopic deformities showed biocompatibility of TMSC-GHH. Additionally, visceral fat reduction effects by TMSC-GHH further supported their therapeutic potential. TMSC provided therapeutic benefits toward osteoporosis only when embedded in GHH, and showed potential as a supplement or alternative to current therapies
Plasmon-Mediated Electrocatalysis for Sustainable Energy: From Electrochemical Conversion of Different Feedstocks to Fuel Cell Reactions
No full textThe incorporation of plasmonic properties recently emerged as an advanced strategy for achieving high-performance catalysis. The hot carriers and near-field enhancement induced by localized surface plasmon resonance (LSPR) excitation are the key parameters that are responsible for the enhanced performance. Thus, the logical combination of the plasmonic nanostructures and electrocatalytic materials can be an effective strategy for further widening application of the plasmonic effect. This short Review provides a concise overview of the fundamental principles of LSPR; the mechanism of plasmon-enhanced electrocatalysis; alternative design methods of plasmonic nanomaterials for various catalytic systems; and recent progress in plasmon-mediated electrocatalysis for the production of energy, including electrochemical conversion of different feedstocks into fuels along with fuel cell catalysis. This Review also sheds light on the areas where major advancements are required to further improve the field of plasmon-mediated electrocatalysis to achieve a major paradigm shift toward a sustainable future. © 2018 American Chemical Society
Aminophylline and Ephedrine, but Not Flumazenil, Inhibit the Activity of the Excitatory Amino Acid Transporter 3 Expressed in Xenopus Oocytes and Reverse the Increased Activity by Propofol
No full textWe investigated the effects of flumazenil, aminophylline, and ephedrine on the excitatory amino acid transporter type 3 (EAAT3) activity and the interaction with propofol. EAAT3 was expressed in the Xenopus oocytes. L-Glutamate-induced membrane currents were measured using the two-electrode voltage clamp at various drug concentrations. Oocytes were preincubated with protein kinase C- (PKC-) activator, or inhibitor, and phosphatidylinositol 3-kinase (PI3K) inhibitor. To study the interaction with propofol, oocytes were exposed to propofol, propofol + aminophylline, or ephedrine. Aminophylline and ephedrine significantly decreased EAAT3 activity. Aminophylline (95 μM) and ephedrine (1.19 μM) significantly decreased Vmax, but not Km of EAAT3, for glutamate. The phorbol 12-myristate-13-acetate-induced increase in EAAT3 activity was abolished by aminophylline or ephedrine. The decreased EAAT3 activities by PKC inhibitors (staurosporine, chelerythrine) and PI3K inhibitor (wortmannin) were not significantly different from those by aminophylline or ephedrine, as well as those by PKC inhibitors or PI3K inhibitor + aminophylline or ephedrine. The enhanced EAAT3 activities induced by propofol were significantly abolished by aminophylline or ephedrine. Aminophylline and ephedrine inhibit EAAT3 activity via PKC and PI3K pathways and abolish the increased EAAT3 activity by propofol. Our results indicate a novel site of action for aminophylline and ephedrine. © 2018 Sohyeon Moon and Hee Jung Baik.National Research Foundation of Kore
GATA1 Expression in BCR/ABL1-negative Myeloproliferative Neoplasms
No full textBackground: This study aimed to determine GATA1 expression levels to better characterize subgroups in BCR/ABL1-negative myeloproliferative neoplasms (MPNs). Methods: This study enrolled 49 patients diagnosed as having BCR/ABL1-negative MPN on the basis of the 2016 World Health Organization classification : nine polycythemia vera (PV), 17 essential thrombocythemia (ET), 12 prefibrotic primary myelofibrosis (prePMF), and 11 overt primary myelofibrosis (PMF). Relevant clinical and laboratory data were retrieved from the medical records. The molecular analysis of CALR and MPL mutations and quantification of JAK2 V617F allele burden were performed. GATA1 expression was assessed by an immunohistochemical assay on bone marrow biopsy. GATA1 expression was analyzed serially in 18 patients. Results: GATA1 expression decreased significantly in PMF compared with that in other subtypes, while no statistical difference was identified between ET and prePMF. GATA1 expression did not differ according to the mutation profiles or the allele burden of JAK2 V617F, but it decreased significantly in patients with overt fibrosis or leukemic transformation. Conclusions: Our results suggest that GATA1 expression is significantly low in PMF and decreases with progressive fibrosis and possibly with leukemic transformation, although our attempt to accurately distinguish between subgroups using GATA1 immunohistochemical approach did not achieve statistical significance. A large patient cohort with long term follow-up is required to evaluate the prognostic value of GATA1 expression
Lipidomic profiling reveals free fatty acid alterations in plasma from patients with atrial fibrillation
No full textAtrial fibrillation (AF) is the most common cardiac arrhythmia, and its incidence is increasing worldwide. One method used to restore sinus rhythm is direct current cardioversion (DCCV). Despite the high success rate of DCCV, AF typically recurs within the first 2 weeks. However, our understanding of the pathophysiology of AF recurrence, incidence, and progression are highly limited. Lipidomic profiling was applied to identify altered lipids in plasma from patients with AF using ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry coupled with multivariate statistical analysis. Partial least-squares discriminant analysis revealed a clear separation between AF patients and healthy controls. The levels of several lipid species, including fatty acids and phospholipids, were different between AF patients and healthy controls, indicating that oxidative stress and inflammation are associated with the pathogenesis of AF. Similar patterns were also detected between recurrent and non-recurrent AF patients. These results suggest that the elevated saturated fatty acid and reduced polyunsaturated fatty acid levels in AF patients may be associated with enhanced inflammation and that free fatty acid levels may play a crucial role in the development and progression of AF. © 2018 Jung et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
High dietary glycemic load is associated with poor functional outcome in patients with acute cerebral infarction
No full textBackground and Purpose Elevated postprandial blood glucose is a critical risk factor for stroke. The dietary glycemic load (GL) and glycemic index (GI) are frequently used as markers of the postprandial blood glucose response to estimate the overall glycemic effect of diets. We hypothesized that high dietary GL, GI, or total carbohydrate intake is associated with a poor functional outcome in patients with acute ischemic stroke. Methods We prospectively included 263 first-ever ischemic stroke patients who completed a semiquantitative food-frequency questionnaire. The dietary GL, GI, and total carbohydrate intake were investigated by examining the average frequency of intake during the previous year based on reference amounts for various food items. Poor functional outcome was defined as a score on the modified Rankin Scale (mRS) of ≥3 at 3 months after stroke. Results The patients were aged 65.4±11.7 years (mean±standard deviation), and 58.2% of them were male. A multivariate analysis adjusted for age, sex, marital status, prestroke mRS score, diabetes mellitus, hyperlipidemia, body mass index, triglycerides, low-density lipopro-tein, hemoglobin A1c, stroke classification, and National Institutes of Health Stroke Scale score, early neurological deterioration, and high-grade white-matter hyperintensities revealed that the dietary GL and total carbohydrate intake were associated with a poor functional outcome, with odds ratios for the top quartile relative to the bottom quartile of 28.93 (95% confidence interval= 2.82–296.04) and 36.84 (95% confidence interval=2.99–453.42), respectively (p for trend=0.002 and 0.002, respectively). In contrast, high dietary GI was not associated with a poor functional outcome (p for trend=0.481). Conclusions Increased dietary GL and carbohydrate intake were associated with a poor short-term functional outcome after an acute ischemic stroke. © 2018 Korean Neurological Association
Breastfeeding and Maternal hypertension
No full textBACKGROUND: Little is known about the relationship between breastfeeding and hypertension. We performed this study to identify whether breastfeeding itself influenced maternal hypertension and whether degree of obesity or insulin sensitivity would contribute to the relationship between breastfeeding and hypertension in postmenopausal women. METHODS: Our study population comprised 3,119 nonsmoking postmenopausal women aged 50 years or above in the 2010-2011 Korea National Health and Nutrition Examination Survey. We performed logistic regression analyses to examine the relationship between breastfeeding and hypertension and mediation analyses to examine the contributions of obesity and insulin sensitivity to the breastfeeding-hypertension relationship. RESULTS: The odds ratios, with 95% confidence intervals, for hypertension among the highest quintile of number of breastfed children (5-11) and the highest quintile of duration of breastfeeding (96-324 months) were 0.49 (0.31-0.75) and 0.55 (0.37-0.82), respectively, compared to each of lowest quintile groups. The population attributable fractions of hypertension caused by breastfeeding 3 or fewer children and breastfeeding for 56 months or less were 10.2% (P < 0.001) and 6.5% (P = 0.017), respectively. In the mediation analysis, unexpectedly, increased insulin resistance significantly attenuated the protective effect on hypertension of having breastfed more children; additionally, greater obesity and insulin resistance significantly attenuated the protective effects on hypertension of having breastfed for longer. CONCLUSIONS: More children breastfed and longer duration of breastfeeding were associated with lower risk of hypertension in postmenopausal women, and degree of obesity and insulin resistance moderated the breastfeeding-hypertension association. © American Journal of Hypertension, Ltd 2018. All rights reserved