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Introduction: Longitudinal observations of upper limb motor recovery after stroke have suggested that certain subgroups may exhibit distinct recovery patterns. Here we sought to examine whether the predictive ability for poststroke upper limb motor outcomes could be enhanced by applying conventional stratification strategies. Method: For 60 individuals who suffered the first stroke, upper limb motor impairment was assessed with the upper extremity Fugl-Meyer assessment (UE-FMA) at 2 weeks as a baseline and then 3 months post-stroke. Brain structural damage at baseline was assessed by MRI data-derived markers ranging from traditional lesion size to the lesion load and to the disconnectome. Linear regression models for predicting upper limb motor outcomes (UE-FMA score at 3 months post-stroke) based on baseline upper limb motor impairment (UE-FMA score at 2 weeks post-stroke), brain structural damage, and their combinations were generated, and those with the best predictive performance were determined for individual subgroups stratified according to initial impairment (severe and non-severe), lesion location (cortical and non-cortical), and neurophysiological status (motor evoked potential-positive and motor evoked potential-negative). Results: The best predictions were made by baseline upper limb motor impairment alone for subgroups with less functional impairment (nonsevere) or less structural involvement (non-cortical), but by the combination of baseline upper limb motor impairment and brain structural damage for the other subgroups. The predictive models tailored for subgroups determined according to initial impairment and neurophysiological status yielded a smaller overall error than that for the whole group in upper limb motor outcome predictions. Discussion: The predictive ability for upper limb motor outcomes could be enhanced beyond the one-size-fits-all model for all individuals with stroke by applying specific stratification strategies, with stratification according to initial impairment being the most promising. We expect that predictive models tailored for individual subgroups could lead closer to the personalized prognosis of upper limb motor outcomes after stroke. [ABSTRACT FROM AUTHOR]

Background: We utilized diffusion tensor imaging (DTI) to evaluate the cerebral white matter changes that are associated with phantom limb pain in patients with unilateral arm amputation. It was anticipated that this would complement previous research in which we had shown that changes in cerebral blood volume were associated with the cerebral pain network. Methods: Ten patients with phantom limb pain due to unilateral arm amputation and sixteen healthy age-matched controls were enrolled. The intensity of phantom limb pain was measured by the visual analogue scale (VAS) and depressive mood was assessed by the Hamilton depression rating scale. Diffusion tensor-derived parameters, including fractional anisotropy, mean diffusivity, axial diffusivity (AD), and radial diffusivity (RD), were computed from the DTI. Results: Compared with controls, the cases had alterations in the cerebral white matter as a consequence of phantom limb pain, manifesting a higher AD of white matter in both hemispheres symmetrically after adjusting for individual depressive moods. In addition, there were associations between the RD of white matter and VAS scores primarily in the hemispheres related to the missing hand and in the corpus callosum. Conclusions: The phantom limb pain after unilateral arm amputation induced plasticity in the white matter. We conclude that loss of white matter integrity, particularly in the hemisphere connected with the missing hand, is significantly correlated with phantom limb pain. [ABSTRACT FROM AUTHOR]

Background: We utilized diffusion tensor imaging (DTI) to evaluate the cerebral white matter changes that are associated with phantom limb pain in patients with unilateral arm amputation. It was anticipated that this would complement previous research in which we had shown that changes in cerebral blood volume were associated with the cerebral pain network. Methods: Ten patients with phantom limb pain due to unilateral arm amputation and sixteen healthy age-matched controls were enrolled. The intensity of phantom limb pain was measured by the visual analogue scale (VAS) and depressive mood was assessed by the Hamilton depression rating scale. Diffusion tensor-derived parameters, including fractional anisotropy, mean diffusivity, axial diffusivity (AD), and radial diffusivity (RD), were computed from the DTI. Results: Compared with controls, the cases had alterations in the cerebral white matter as a consequence of phantom limb pain, manifesting a higher AD of white matter in both hemispheres symmetrically after adjusting for individual depressive moods. In addition, there were associations between the RD of white matter and VAS scores primarily in the hemispheres related to the missing hand and in the corpus callosum. Conclusions: The phantom limb pain after unilateral arm amputation induced plasticity in the white matter. We conclude that loss of white matter integrity, particularly in the hemisphere connected with the missing hand, is significantly correlated with phantom limb pain. [ABSTRACT FROM AUTHOR]

Internet gaming disorder (IGD) is often diagnosed on the basis of nine underlying criteria from the latest version of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5). Here, we examined whether such symptom-based categorization could be translated into computation-based classification. Structural MRI (sMRI) and diffusion-weighted MRI (dMRI) data were acquired in 38 gamers diagnosed with IGD, 68 normal gamers diagnosed as not having IGD, and 37 healthy non-gamers. We generated 108 features of gray matter (GM) and white matter (WM) structure from the MRI data. When regularized logistic regression was applied to the 108 neuroanatomical features to select important ones for the distinction between the groups, the disordered and normal gamers were represented in terms of 43 and 21 features, respectively, in relation to the healthy non-gamers, whereas the disordered gamers were represented in terms of 11 features in relation to the normal gamers. In support vector machines (SVM) using the sparse neuroanatomical features as predictors, the disordered and normal gamers were discriminated successfully, with accuracy exceeding 98%, from the healthy non-gamers, but the classification between the disordered and normal gamers was relatively challenging. These findings suggest that pathological and non-pathological gamers as categorized with the criteria from the DSM-5 could be represented by sparse neuroanatomical features, especially in the context of discriminating those from non-gaming healthy individuals. [ABSTRACT FROM AUTHOR]

Background: Although the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation has been recommended for accurate estimates of glomerular filtration rate (eGFR), there is little information regarding differences in GFR estimates obtained using the Cockcroft-Gault (CG) or Modification of Diet in Renal Disease (MDRD) equations in East Asian cancer patients. We investigated discrepancies in GFR and toxicities in patients treated with cisplatin-based chemotherapy using three equations equations. Methods: A total of 229 patients were retrospectively recruited. We calculated eGFR using the three equations and separated patients into three categories based on GFR < 10 (group A), 10-50 (group B), and > 50 (group C) mL/min/1.73m². We analyzed chemotherapy toxicities. Results: The mean eGFR calculated using the CG was the lowest of the values derived using the three equations. Estimates using the MDRD and CKD-EPI equations resulted in reclassifying 32 (71.1%) and 33 (73.3%) of 45 patients, originally placed in group B using the CG into group C. However, only 1 (7.7%) of 13 patients placed in group B using the MDRD were reclassified into group C using the CKD-EPI. Twenty-eight of 45 patients classified into group B using the CG equation were treated with reduced doses of cisplatin. However, these patients did not show significant differences in toxicities compared with other patients taking full doses of cisplatin. Conclusion: The CG equations underestimated GFR compared to the MDRD and CKD-EPI equations. Therefore, when GFR is estimated using CG equations, East Asian cancer patients may receive insufficient doses of chemotherapeutic agents, including cisplatin. [ABSTRACT FROM AUTHOR]

Val66Met, a naturally occurring polymorphism in the human brain-derived neurotrophic factor (BDNF) gene resulting in a valine (Val) to methionine (Met) substitution at codon 66, plays an important role in neuroplasticity. While the effect of the BDNF Val66Met polymorphism on local brain structures has previously been examined, its impact on the configuration of the graph-based white matter structural networks is yet to be investigated. In the current study, we assessed the effect of the BDNF polymorphism on the network properties and robustness of the graph-based white matter structural networks. Graph theory was employed to investigate the structural connectivity derived from white matter tractography in two groups, Val homozygotes (n = 18) and Met-allele carriers (n = 55). Although there were no differences in the global network measures including global efficiency, local efficiency, and modularity between the two genotype groups, we found the effect of the BDNF Val66Met polymorphism on the robustness properties of the white matter structural networks. Specifically, the white matter structural networks of the Met-allele carrier group showed higher vulnerability to targeted removal of central nodes as compared with those of the Val homozygote group. These findings suggest that the central role of the BDNF Val66Met polymorphism in regards to neuroplasticity may be associated with inherent differences in the robustness of the white matter structural network according to the genetic variants. Furthermore, greater susceptibility to brain disorders in Met-allele carriers may be understood as being due to their limited stability in white matter structural connectivity. [ABSTRACT FROM AUTHOR]

There are several types of steel products, such as wire rods, cold-rolled coils, hot-rolled coils, thick plates, and electrical sheets. Surface stains on cold-rolled coils are considered defects. However, surface stains on thick plates are not considered defects. A conventional optical structure is composed of a camera and lighting module. A defect inspection system that uses a dual lighting structure to distinguish uneven defects and color changes by surface noise is proposed. In addition, an image processing algorithm that can be used to detect defects is presented in this paper. The algorithm consists of a Gabor filter that detects the switching pattern and employs the binarization method to extract the shape of the defect. The optics module and detection algorithm optimized using a simulator were installed at a real plant, and the experimental results conducted on thick steel plate images obtained from the steel production line show the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Background: Motor deficit after stroke is related to regional anatomical damage.Objective: To examine the influence of lesion location on upper limb motor deficit in chronic patients with stroke.Methods: Lesion likelihood maps were created from T1-weighted structural MRI in 33 chronic patients with stroke with either purely subcortical lesions (SC, n=19) or lesions extending to any of the cortical motor areas (CM, n=14). We estimated lesion likelihood maps over the whole brain and applied multivoxel pattern analysis to seek the contribution weight of lesion likelihood to upper limb motor deficit. Among 5 brain regions of interest, the brain region with the greatest contribution to motor deficit was determined for each subgroup.Results: The corticospinal tract was most likely to be damaged in both subgroups. However, while damage in the corticospinal tract was the best indicator of motor deficit in the SC patients, motor deficit in the CM patients was best explained by damage in brain areas activated during handgrip.Conclusions: Quantification of structural damage can add to models explaining motor outcome after stroke, but assessment of corticospinal tract damage alone is unlikely to be sufficient when considering patients with stroke with a wide range of lesion topography. [ABSTRACT FROM AUTHOR]

Purpose: In brain-computer interfaces (BCIs), electrical brain signals during motor imagery are utilized as commands connecting the brain to a computer. To use BCI in patients with stroke, unique brain signal changes should be characterized during motor imagery process. This study aimed to examine the trial-dependent motor-imagery-related activities in stroke patients. Methods: During the recording of electroencephalography (EEG) signals, 12 chronic stroke patients and 11 age-matched healthy controls performed motor imagery finger tapping at 1.3 sec intervals. Trial-dependent brain signal changes were assessed by analysis of the mu and beta bands. Results: Neuronal activity in healthy controls was observed over bilateral hemispheres at the mu and beta bands regardless of changes in the trials, whereas neuronal activity in stroke patients was mainly seen over the ipsilesional hemisphere at the beta band. With progression to repeated trials, healthy controls displayed a decrease in cortical activity in the contralateral hemisphere at the mu band and in bilateral hemispheres at the beta band. In contrast, stroke patients showed a decreasing trend in cortical activity only over the ipsilesional hemisphere at the beta band. Conclusions: Trial-dependent changes during motor imagery learning presented in a different manner in stroke patients. Understanding motor imagery learning in stroke patients is crucial for enhancing the effectiveness of motor-imagery-based BCIs. [ABSTRACT FROM AUTHOR]

Background: Cerebrolysin is a neuropeptide preparation with neuroprotective and neurorestorative effects. Combining Cerebrolysin treatment with a standardized rehabilitation program may have a potential synergistic effect in the subacute stage of stroke. This study aims to evaluate whether Cerebrolysin provides additional motor recovery on top of rehabilitation therapy in the subacute stroke patients with moderate to severe motor impairment. Methods: This phase IV trial was designed as a prospective, multicenter, randomized, double-blind, placebo-controlled, parallel-group study. A total of 70 patients (Cerebrolysin n = 35, placebo n = 35) with moderate to severe motor function impairment were included within 7 days after stroke onset and were randomized to receive a 21-day treatment course of either Cerebrolysin or placebo, given in addition to standardized rehabilitation therapy. Assessments were performed at baseline, immediately after treatment as well as 2 and 3 months after stroke onset. The plasticity of motor system was assessed by diffusion tensor imaging and with resting state functional magnetic resonance imaging. Results: Both groups demonstrated significant improvement in motor function (p < 0.05); however, no significant difference was found between the two groups. In the stroke patients with severe motor impairment, the Cerebrolysin group exhibited significantly more improvement in motor function compared with the placebo group (p < 0.05). Effects of Cerebrolysin were demonstrated as restricted increments of corticospinal diffusivity and as recovery of the sensorimotor connectivity. Conclusion: The combination of standard rehabilitation therapy with Cerebrolysin treatment in the subacute stroke has shown additional benefit on motor recovery and plastic changes of the corticospinal tract in patients with severe motor impairment. Trial Registration: NCT01996761 (November 5, 2013). [ABSTRACT FROM AUTHOR]

Objective To investigate whether early stage diffusion tensor tractography (DTT) values predict motor function at 3 months after onset in supratentorial stroke patients with severe motor involvement. Methods A retrospective study design was used to analyze medical records and neuroimaging data of 49 supratentorial stroke patients with severe motor involvement. Diffusion tensor imaging was assessed within 3 weeks after stroke in all patients. Three-dimensional tractography of the ipsilateral corticospinal tract (CST) was performed using the fiber assignment of the continuous tracking algorithm. The two-step DTT analysis was used. The first step was classification according to ipsilateral CST visualization. The second step was a quantitative analysis of the visible-CST group parameters. Motor function was assessed at 2 weeks and at 3 months after stroke. Comparative and correlation analyses were performed between DTT-derived measures and motor assessment scores. Results Motor function of the upper extremity at 3 months after stroke was significantly higher in the visible-CST group than that in the nonvisible-CST group (p<0.05). Early stage fractional anisotropy was of DTT correlated significantly with upper extremity motor function at 3 months after stroke in the visible-CST group (p<0.05). Conclusion These results demonstrate that early DTT-derived measures predict motor recovery in the upper extremity at 3 months after onset in supratentorial stroke patients with severe motor involvement. [ABSTRACT FROM AUTHOR]

Background: High-dose remifentanil-based anesthesia is associated with opioid-induced hyperalgesia (OIH) and post-anesthetic shivering (PAS). These effects can be prevented by N-methyl-d-aspartate (NMDA) receptor antagonists. This study aimed to investigate correlations between OIH and PAS caused by high-dose remifentanil and the effects of low-dose ketamine on OIH and PAS. Methods: Seventy-five patients scheduled for single-port laparoscopic gynecologic surgery were randomly allocated into three groups, each of which received intraoperative remifentanil: group L at 0.1 μg/kg/min; group H at 0.3 μg/kg/min; and group HK at 0.3 μg/kg/min plus 0.25 mg/kg ketamine just before incision, followed by a continuous infusion of 5 μg/kg/min ketamine until skin closure. Results: PAS, postoperative tactile pain threshold, and the extent of hyperalgesia in group H were significantly different (P < 0.05) than in the other two groups. PAS was significantly correlated with OIH, including mechanically evoked pain such as postoperative tactile pain threshold (r = -0.529, P = 0.01) (r = -0.458, P = 0.021) and the extent of hyperalgesia (r = 0.537, P = 0.002) (r = 0.384, P = 0.031), respectively, in group H and group HK. Notably, both groups were treated with high-dose remifentanil. Tympanic membrane temperature, time to first postoperative analgesic requirement, post-operative pain scores, analgesic consumption, and cumulative patient-controlled analgesia volume containing morphine were comparable in all three groups. Conclusions: OIH, including the enhanced perception of pain, and PAS were both associated with high-dose remifentanil, were significantly correlated and were attenuated by a low dose of ketamine. This suggests that a common mechanism in part mediated through activation of the central glutamatergic system (e.g., NMDA receptors), underlies the two effects caused by high doses of remifentanil. [ABSTRACT FROM AUTHOR]

Purpose: The utility of the expression of glucose-regulated protein 78 (GRP78) in the evaluation of prognosis depends on the type of tumor. Hence, we aimed to examine the impact of expression of GRP78 and Bcl-2, which are used in the existing prognostic evaluation of ureter tumors, in the evaluation of recurrence and survival rates of ureter tumors. Materials and Methods: In 53 patients who had undergone radical nephroureterectomy for a ureter tumor from March 2002 to March 2012, age, sex, T stage, nuclear grade, bladder recurrence, and survival rate were analyzed at the time of the patient's surgery depending on the extent of immunohistochemical expression of GRP78 and Bcl-2. Results: GRP78 was overexpressed in 25 patients (47.2%). When GRP78 was overexpressed, there was a high T stage (p=0.001) and nuclear grade (p=0.007) and a lot of bladder recurrence (40.0%, p=0.034). Bcl-2 was overexpressed in 16 patients (30.1%), and there were no significant associations with any risk factors (p>0.05, respectively). In the multivariate analysis regarding bladder recurrence, the recurrence rate was higher with higher pT stage (p=0.048) and when GRP78 (p=0.033) was overexpressed. In the Kaplan-Meier survival analysis, although the survival rate was significantly lower in the group in which GRP78 was overexpressed (p=0.03), there was no correlation between Bcl-2 overexpression and survival rate (p=0.07). Conclusions: Patients with ureter tumors who had overexpression of GRP78 had a high T stage and nuclear grade, a lot of bladder recurrence, and a low survival rate. Therefore, if GRP78 is overexpressed in ureter tumor patients, active postoperative follow-up should be carried out. [ABSTRACT FROM AUTHOR]

Purpose: A ureter obstruction caused by a ureteral stone results in inflammatory changes in the proximal submucosal layer and prevents the spontaneous passage of the ureteral stone. Accordingly, we analyzed the relationship between the spontaneous passage rates of ureteral stones less than 8 mm in size and serum C-reactive protein (CRP) levels and neutrophil percentages. Materials and Methods: A total of 187 patients who were diagnosed with ureteral stones less than 8 mm in size and were managed consecutively at Keimyung University Dongsan Medical Center from January 2001 to January 2011 were retrospectively analyzed. Ureteral stone removal was defined as no ureteral stone shown in an imaging test without any treatment for 8 weeks after diagnosis. The patients were divided into three groups according to the levels of serum CRP and into two groups according to neutrophil percentage. The associations between these factors and ureteral stone passage rates were then examined. Results: The ureteral stone passage rates of the low serum CRP level group, the medium serum CRP level group, and the high serum CRP level group were 94.1% (159/169), 70% (7/10), and 50.0% (4/8), respectively. The passage rates of ureteral stones in the group with a normal neutrophil percentage and in the group with a higher neutrophil percentage were 94.5% (121/128) and 83.1% (49/59), respectively (p=0.011). Conclusions: Measuring serum CRP levels and neutrophil percentages in patients with small ureteral stones of less than 8 mm is useful in predicting whether the stone will be spontaneously passed. When the serum CRP level and neutrophil percentage of a patient are high, aggressive treatment such as extracorporeal shock wave lithotripsy should be considered. [ABSTRACT FROM AUTHOR]

Background. This study aimed to delineate the cerebral attentional network in patients with traumatic brain injury (TBI) and assess for adaptations in this network in response to a rehabilitation intervention. Methods. Seventeen patients with TBI and 15 healthy subjects underwent functional magnetic resonance imaging (fMRI) using a visuospatial attention task. Ten TBI patients who successfully completed attentional training had a follow-up fMRI. Results. In the TBI patients, fMRI analysis showed more activation in the frontal and temporoparietal lobes, as well as less activation in the anterior cingulated gyrus, SMA, and temporooccipital regions compared to the healthy subjects. Following cognitive training, the TBI patients improved performance of attention tasks accompanied by changes in attentional network activation; the activity of the frontal lobe decreased, whereas activation of the anterior cingulate cortices and precuneus increased. Conclusions. These findings demonstrate the plasticity and training induced redistribution of the visuospatial attentional network in TBI patients. [ABSTRACT FROM AUTHOR]

This paper presents a method for stochastic prediction of voltage sags caused by faults in a power system. The area of vulnerability must be determined to estimate the expected sag frequency (ESF) at a sensitive load site. However, the area of vulnerability is not easy to identify in a large meshed network. In the paper, the residual phase voltage equations for balanced and unbalanced faults are presented, and an efficient method to determine the area of vulnerability in a large meshed network is described. An ESF estimation method based on Information Technology Industry Council (ITIC) curve is also described. The developed method was applied to the IEEE 30-bus test system. [ABSTRACT FROM AUTHOR]

This article presents a training system for live-line workers. The developed training system is based on immersive virtual reality and automatic speech recognition technology. The training is focused on live-line Cut-Out-Switch (COS) replacement work in a distribution system. Most work in power systems must be free of interruption, so it is carried out by live-line techniques. However, these techniques have increased the number of accidents by electric shock. Because most electric accidents are due to live-line work, it is important to train live-line workers. The proposed training system provides repeated and cost-effective training for a small space. It also guarantees safety during training operations. In this article, the background of live-line techniques and the work procedure of COS replacement are presented. The architecture of the developed system, the creation of the virtual work environment, and the collision detection among virtual objects are also described. [ABSTRACT FROM AUTHOR]

Three-dimensional (3-D) information on nervous tissue is essential for the understanding of brain function. Especially, 3-D synaptic analyses on serial ultrathin sections with transmission electron microscopy (TEM) have contributed to the knowledge on neural plasticity associated with various pathophysiological conditions. The 3-D reconstruction procedures, however, not only require a great amount of expertise but also include time-consuming processes. Here, we carried out computer-assisted 3-D reconstruction of parallel fibre–Purkinje cell synapses based on 250 nm serial sections using high-voltage electron microscopy (HVEM). The 3-D synapse models were constructed more efficiently and rapidly compared with conventional serial TEM reconstruction. This result suggests that 3-D reconstruction with thicker sections and HVEM is a useful method to study synaptic connectivity. [ABSTRACT FROM AUTHOR]