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Background and purpose Increasing evidence suggests the presence of demyelination in the normal-appearing white matter ( NAWM) of patients with neuromyelitis optica spectrum disorder ( NMOSD). The objective was to determine the presence of subclinical demyelination in the NAWM of patients with NMOSD using myelin water imaging ( MWI). Methods Whole brain and regions-of-interest ( ROIs) analyses, including the centrum semiovale, corona radiata, genu and splenium of the corpus callosum, and optic radiation, were conducted in the NAWM of 28 NMOSD patients and 18 healthy controls ( HCs) using two MWI modalities: conventional MWI and direct visualization of short transverse relaxation time component (Vi STa) MWI. Results Conventional myelin water fractions ( MWFs) of the global NAWM and three ROIs (centrum semiovale, corona radiata, and genu of the corpus callosum) were slightly lower in NMOSD patients than in HCs, although not statistically significant. On the other hand, Vi STa MWF values of the global NAWM and all ROIs except the genu of the corpus callosum were significantly lower in NMOSD patients relative to HCs. In particular, the MWF in the optic radiation was significantly reduced in NMOSD patients relative to HCs in both MWI methods, even in patients who had no brain involvement. Additionally, patients with optic neuritis showed lower MWF than patients without optic neuritis and a negative correlation was identified between the MWF of the optic radiation and visual functional system score. Conclusions This study identified the presence of widespread demyelination in the NAWM of NMOSD patients and highlighted the optic radiation as a site of marked demyelination. [ABSTRACT FROM AUTHOR]

The carbothermic reduction of MnO2with graphite has been investigated for the reduction mechanism in the temperature range of 1000–1300°C. Although several researchers studied the reduction step from MnO2to MnO, it was attempted to employ thein situtesting of reduction behaviour with the analysis of product gas composition simultaneously from the different points of view. The overall reduction rate increased with temperature, which was controlled by the carbon gasification. It is because the reduction rate of MnO2to MnO was much faster than the carbon gasification at the experimental temperatures. This was confirmed by the generation of negligible amount of CO compared with CO2in the analysis of product gases. Furthermore, the results could explain the difficult formation of manganese carbide from MnO2in contrast with the carbide formation from pure MnO. [ABSTRACT FROM PUBLISHER]

Background/Aims: The purpose of this study was to determine the effect of performing laparoscopic cholecystectomy on patients undergoing laparoscopic-assisted gastrectomy for gastric cancer. Methods: This single center study involved a retrospective review of a database of 400 patients who underwent consecutive laparoscopic-assisted gastrectomy for early gastric cancer from June 2003 to July 2007. Outcomes in 26 patients who underwent both laparoscopic-assisted gastrectomy and laparoscopic cholecystectomy were compared with outcomes from 364 patients who underwent laparoscopic-assisted gastrectomy without laparoscopic cholecystectomy. Results: There were no postoperative 30-day mortalities in the combined cholecystectomy group. The mean surgery duration, time to first flatus and postoperative hospital stay for the laparoscopic gastric resection without combined operation were 181.7 min, 2.7 days and 9.7 days, respectively, and 196.7 min, 2.6 days and 8.8 days, respectively, for the combined cholecystectomy group. None of the postoperative complications was related to combined cholecystectomy. Conclusion: Performing a combined cholecystectomy prolonged the mean surgery duration by approximately 15 min, but had no effect on surgical outcomes. It appears that performing a cholecystectomy at the same time as laparoscopic gastric resection is safe and feasible in patients with both early gastric cancer and gallbladder disease. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

A fast and accurate current programming method with a current unity-gain amplifier which provides high gain and driving capability has been designed. Experimental results show that the maximum error of the programming current in pixels is less than 0.22 least significant bit using the proposed current driving method and the lowest grey-level current, 6.7 nA, can be successfully programmed within 19 µs. The power consumption of the proposed current driving method with a channel is 10.5 µW. This performance is good enough to apply to a 12-inch-wide extended graphics array resolution format active matrix organic light emitting diode display with 8-bit greyscale. [ABSTRACT FROM AUTHOR]

Background and purpose Studies on cortical involvement and its relationship with cognitive function in patients with neuromyelitis optica spectrum disorder (NMOSD) remain scarce. The objective of this study was to compare cortical thickness on magnetic resonance imaging (MRI) between patients with NMOSD and multiple sclerosis (MS) and to investigate its relationship with clinical features and cognitive function. Methods This observational clinical imaging study of 91 patients with NMOSD, 52 patients with MS and 44 healthy controls was conducted from 1 December 2013 to 30 April 2015 at the institutional referral center. Three tesla MRI of the brain and neuropsychological tests were performed. Cortical thickness was measured using three-dimensional surface-based analysis. Results Both sets of patients exhibited cortical thinning throughout the entire brain cortex. Patients with MS showed a significantly greater reduction in cortical thickness over broad regions of the bilateral frontal and parieto-temporal cortices and the left precuneus compared to those with NMOSD. Memory functions in patients with MS were correlated with broad regional cortical thinning, whereas no significant associations were observed between cortical thickness and cognitive function in patients with NMOSD. Conclusions Widespread cortical thinning was observed in patients with NMOSD and MS, but the extent of cortical thinning was greater in patients with MS. The more severe cortical atrophy may contribute to memory impairment in patients with MS but not in those with NMOSD. These results provide in vivo evidence that the severity and clinical relevance of cortical thinning differ between NMOSD and MS. [ABSTRACT FROM AUTHOR]