Clinical Characteristics of a Nationwide Hospital-based Registry of Mild-to-Moderate Alzheimer's Disease Patients in Korea: A CREDOS (Clinical Research Center for Dementia of South Korea) Study

With rapid population aging, the socioeconomic burden caused by dementia care is snowballing. Although a few community-based studies of Alzheimer's disease (AD) have been performed in Korea, there has never been a nationwide hospital-based study thereof. We aimed to identify the demographics and clinical characteristics of mild-to-moderate AD patients from the Clinical Research Center for Dementia of Korea (CREDOS) registry. A total of 1,786 patients were consecutively included from September 2005 to June 2010. Each patient underwent comprehensive neurological examination, interview for caregivers, laboratory investigations, neuropsychological tests, and brain MRI. The mean age was 74.0 yr and the female percentage 67.0%. The mean period of education was 7.1 yr and the frequency of early-onset AD (< 65 yr old) was 18.8%. Among the vascular risk factors, hypertension (48.9%) and diabetes mellitus (22.3%) were the most frequent. The mean score of the Korean version of Mini-Mental State Examination (K-MMSE) was 19.2 and the mean sum of box scores of Clinical Dementia Rating (CDR-SB) 5.1. Based on the well-structured, nationwide, and hospital-based registry, this study provides the unique clinical characteristics of AD and emphasizes the importance of vascular factors in AD in Korea

Asymptomatic Secondary Aortoduodenal Fistula Incidentally Diagnosed During a Health Check-up: A Case Report

Secondary aortoenteric fistulas (AEFs) are an uncommon but fatal complication of abdominal aortic reconstructive surgery. Aortoduodenal fistulas (ADFs) are the most frequent secondary AEFs (80%). The incidence of secondary AEFs is increasing because of the increasing number of individuals undergoing aortic aneurysm repairs with prosthetics. In most cases of secondary AEFs, surgical repair is performed with the patient in a poor condition, owing to late diagnosis. Thus, an early diagnosis is crucial. We report a case of an asymptomatic secondary ADF that was incidentally diagnosed using esophagogastroduodenoscopy (EGD) and computed tomography during a health check-up and was successfully repaired, with the patient in a stable condition even after the development of life-threatening symptoms. Based on our case, we suggest that noticing unexplained leukocytosis in regular hematological examination and performing surveillance EGD in an asymptomatic individual who has undergone abdominal aortic reconstructive surgery may aid in the early diagnosis of secondary AEFs before fatal complications manifest

Ultrahigh strength and modulus of polyimide-carbon nanotube based carbon and graphitic fibers with superior electrical and thermal conductivities for advanced composite applications

Development of carbon fibers (CFs) with high strength and high modulus for structural applications in CF-reinforced polymer (CFRP) industry has been a challenge. Herein, we propose a method for manufacturing highly oriented polymer???carbon nanotube (CNT) composite fibers having high strength (4.8 ?? 0.2 GPa), modulus (390 ?? 48 GPa), and electrical conductivity (5.75 ?? 0.84 MS m-1) by a liquid crystalline wet-spinning process. The use of chlorosulfonic acid (CSA) as a solvent for CNTs and polyimide (PI) promotes dispersion and enables the production of high-performance composite fibers. In addition, the functional groups of PI in composite fibers improve the interfacial shear strength with epoxy resin without sizing additives by 72% compared to that of CNT fibers. Carbonization and graphitization of the composite fibers with an optimal ratio of PI (30%) and CNT cause significant improvement in their mechanical (tensile strength; 6.21 ?? 0.3 GPa and modulus; 701 ?? 47 GPa) and thermal properties (496 ?? 38 W m???1 K???1) by reducing voids and improving orientation. We believe that the polymer???CNT composites and their CFs with high strength and high modulus would be the next-generation CFs for aerospace and defense industry

Chemical Method for Improving Both the Electrical Conductivity and Mechanical Properties of Carbon Nanotube Yarn via Intramolecular Cross-Dehydrogenative Coupling

Chemical post-treatment of the carbon nanotube fiber (CNTF) was carried out via intramolecular cross-dehydrogenative coupling (ICDC) with FeCl₃ at room temperature. The Raman intensity ratio of the G band to the D band (<i>I</i>_G/<i>I</i>_D ratio) of CNT fiber increased from 2.3 to 4.6 after ICDC reaction. From the XPS measurements, the <i>A</i>_CC/<i>A</i>_C–C ratio of the CNT fiber increased from 3.6 to 4.8. It is of keen interest that both the electrical conductivity and tensile strength of CNT yarn improved to 3.5 × 10³ S/cm and 420 MPa, which is 180 and 200% higher than that of neat CNT yarn