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Kang DH, Hwang YH, Kim YS, Bae GY, Lee SJ. Cognitive Outcome and Clinically Silent Thromboembolic Events After Coiling of Asymptomatic Unruptured Intracranial Aneurysms. Neurosurgery 2012; 72:638-45; discussion 645. [DOI: 10.1227/neu.0b013e3182846f74] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Abstract
BACKGROUND:
Thromboembolic events are the most common complication after coiling of unruptured intracranial aneurysms (UIAs). However, it remains unclear whether these clinically silent ischemic lesions (CSILs) have any clinical significance.
OBJECTIVE:
To evaluate cognitive outcome after coil embolization of asymptomatic UIAs and its relationship with CSILs after the procedure.
METHODS:
We prospectively enrolled 40 UIA patients who showed no new focal neurological deficit after coil embolization. CSILs were assessed with diffusion-weighted imaging (DWI) within 1 day after the procedure. A battery of neuropsychological tests was performed 3 times: preoperatively and postoperatively at 1 and 4 weeks after coil embolization.
RESULTS:
The incidence of cognitive impairment after coiling in patients with UIAs was 44% (17 of 39) at 1 week and 19% (7 of 37) at 4 weeks after coil embolization. DWI within 1 day after coil embolization revealed that 60% of patients (24 of 40) showed CSILs. However, no significant difference was found in any mean cognitive scores or in the number of cognitively impaired variables between patients with and without CSILs at weeks 1 and 4. Additional correlation analysis revealed no correlations between the number of CSILs on DWI and the cognitive sum z score at both 1 and 4 weeks.
CONCLUSION:
Exhaustive neuropsychological evaluation of UIA patients who underwent coil embolization demonstrated recovery or improvements from baseline cognitive function after 4 weeks, although some patients still showed cognitive deficits at 4 weeks after the procedure. However, we found no statistically significant relationship between the presence and number of CSILs on DWI and cognitive changes after the procedure.
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Kang DW, Sohn SI, Hong KS, Yu KH, Hwang YH, Han MK, Lee J, Park JM, Cho AH, Kim HJ, Kim DE, Cho YJ, Koo J, Yun SC, Kwon SU, Bae HJ, Kim JS. Reperfusion therapy in unclear-onset stroke based on MRI evaluation (RESTORE): a prospective multicenter study. Stroke 2012; 43:3278-83. [PMID: 23093613 DOI: 10.1161/strokeaha.112.675926] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Unclear-onset strokes are generally excluded from time-based thrombolytic therapy. We examined the safety and feasibility of magnetic resonance imaging-based reperfusion therapy in unclear-onset stroke. METHODS This prospective, multicenter, single-arm study screened consecutive unclear-onset stroke patients within 6 hours of symptom detection. Patients with perfusion-diffusion mismatch>20% and negative or subtle fluid-attenuated inversion recovery changes were treated with intravenous tissue plasminogen activator, intra-arterial therapy, or a combination. The safety outcome was symptomatic intracranial hemorrhage within 48 hours after treatment. The primary efficacy outcome was a 3-month modified Rankin Scale score of 0 to 2. Controls were untreated unclear-onset stroke patients prospectively captured in stroke registries. RESULTS Of 430 unclear-onset stroke patients, 83 (19.3%) received reperfusion therapy (mean age, 67.5±10.4 years; males, 66.3%; median baseline National Institutes of Health Stroke Scale, 14). Symptomatic intracranial hemorrhage with any neurological decline developed in 5 patients (6.0%). Symptomatic intracranial hemorrhage with National Institutes of Health Stroke Scale worsening ≥4 developed in 3 patients (3.6%). Thirty-seven patients (44.6%) achieved modified Rankin Scale score of 0 to 2, and 24 (28.9%) had modified Rankin Scale score of 0 to 1. Female, baseline National Institutes of Health Stroke Scale score, no immediate or early recanalization, and more white blood cells were independent predictors of poor outcome. Compared with untreated controls, the treated group was significantly associated with good outcomes of modified Rankin Scale score of 0 to 2 after adjusting for age, sex, and baseline National Institutes of Health Stroke Scale in logistic regression analysis (odds ratio, 2.25; 95% CI, 1.14-4.49). CONCLUSIONS In unclear-onset stroke patients, magnetic resonance imaging-based reperfusion therapy was feasible and safe. Randomized controlled trials are warranted to confirm the benefit of reperfusion therapy for unclear-onset stroke.
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Kim YW, Kang DH, Hwang YH, Park SP. Unusual MRI findings of dural arteriovenous fistula: isolated perfusion lesions mimicking TIA. BMC Neurol 2012; 12:77. [PMID: 22905952 PMCID: PMC3495893 DOI: 10.1186/1471-2377-12-77] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Accepted: 08/16/2012] [Indexed: 11/25/2022] Open
Abstract
Background The diagnosis of transient ischemic attack (TIA) based on clinical history and objective findings, even including multiparametric MRI, can be misleading. We report two patients who presented with TIA-like deficits with isolated perfusion lesions in corresponding areas but were finally diagnosed as transient neurological symptoms associated with dural arteriovenous fistula (dAVF). Case presentation Two patients presented with transient focal neurological symptoms lasting less than one hour. An isolated perfusion deficit with no diffusion change in the clinically relevant area was shown on brain MRI, indicating transient ischemia as the most plausible cause of neurological symptoms. However, cerebral angiography let to diagnosis of dAVF in both cases. Intracerebral hemorrhage occurred after the initial diagnosis of TIA in one patient, and the small area of perfusion abnormality accompanied by the enlarged cortical vein in the other case helped to identify the dAVF through the further investigation. The pattern of perfusion-weighted imaging in both cases revealed increase of mean transit time and relative cerebral blood volume denoting the venous congestion in a clinically corresponding area. Conclusion Reported cases are uncommon clinical presentation of a dAVF, which can be misdiagnosed as TIA on clinical grounds. In rare cases, the isolated perfusion deficits could be attributable to venous congestion, despite the similar pattern of clinical presentation, such as with TIA.
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Lee PS, Han Q, Yang HY, Lee SH, Hwang YH, Han SH, Kim TW. Effect of thermal annealing on the efficiency of heterojunction photovoltaic cells fabricated using poly(3-hexylthiophene) and methanofullerene, [6,6]-phenyl C61-butyric acid methyl ester. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2012; 12:5577-5581. [PMID: 22966613 DOI: 10.1166/jnn.2012.6247] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The effects of thermal annealing on the efficiency of heterojunction photovoltaic (PV) cells that were fabricated using poly(3-hexylthiophene) (P3HT) and methanofullerene, [6,6]-phenyl C61-butyric acid methyl ester (PCBM) were investigated. The absorption spectra showed that the absorption intensity of the P3HT:PCBM layer that was annealed for 5 min had the highest value among the several samples with different annealing temperatures. The atomic force microscopy image showed that the P3HT:PCBM layer that was annealed for 5 min had the best surface morphology. The X-ray photoelectron spectroscopy demonstrated that the P3HT:PCBM layer that was annealed at 140 degrees C for 10 min enhanced the PCBM aggregation on the surface Al layer that was covered by the P3HT:PCBM layer. The efficiencies of the PV cells that were annealed at 3, 5, and 10 min were approximately 2.7, 4.2, and 3.5%, respectively. Based on the experiment results, the variations in the efficiency of the PV cells due their thermal treatment were described.
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Hwang YH, Kang DH, Kim YW, Kim YS, Park SP, Suh CK. Outcome of forced-suction thrombectomy in acute intracranial internal carotid occlusion. J Neurointerv Surg 2012; 5 Suppl 1:i81-4. [PMID: 22544821 DOI: 10.1136/neurintsurg-2012-010277] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVES Ischemic stroke from acute intracranial distal internal carotid artery (ICA) occlusion usually carries a poor prognosis. Despite the intra-arterial revascularization therapies, the results are still unsatisfactory. The aim of this study was to compare the outcomes between two endovascular techniques, the modified Penumbra System (mPS) and mechanical clot disruption (MCD), and to confirm the influence of recanalization on the outcomes. METHODS In a retrospective review of 39 consecutive cases of acute distal ICA occlusion, the recanalization rates and functional outcomes at 3 months of the two intra-arterial techniques during two consecutive periods (May 2006 to February 2009: MCD technique (n=19) vs March 2009 to August 2010: mPS technique (n=20)) were compared. Univariate and multivariate analyses were performed to determine the predictors of a favorable functional outcome. RESULTS The rate of successful recanalization (Thrombolysis In Cerebral Infarction score 2 or 3) was significantly higher in the mPS group than in the MCD group (85% (17/20) vs 32% (6/19); p=0.001). Favorable outcomes at 3 months (modified Rankin Scale score 0-2) were achieved in 9/20 and 3/19 in the mPS and MCD groups, respectively (45% vs 16%; p=0.048). Binary logistic regression analysis showed that younger age and successful recanalization were independent predictors of a favorable functional outcome. CONCLUSIONS Forced-suction thrombectomy using the mPS technique may be a viable option for acute distal ICA occlusion and could result in more successful recanalization and a more positive clinical outcome.
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Lee JJ, Song HS, Hwang YH, Lee HW, Suh CK, Park SP. Psychiatric symptoms and quality of life in patients with drug-refractory epilepsy receiving adjunctive levetiracetam therapy. J Clin Neurol 2011; 7:128-36. [PMID: 22087206 PMCID: PMC3212598 DOI: 10.3988/jcn.2011.7.3.128] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2011] [Revised: 03/09/2011] [Accepted: 03/09/2011] [Indexed: 01/31/2023] Open
Abstract
Background and Purpose Levetiracetam (LEV) is a new antiepileptic drug that has been found to be effective as an adjunctive therapy for uncontrolled partial seizures. However, the results of several studies suggested that LEV has negative psychotropic effects, including irritability, aggressiveness, suicidality, and mood disorders. We investigated the impact of adjunctive LEV on psychiatric symptoms and quality of life (QOL) in patients with drug-refractory epilepsy (DRE) and determined the risk factors provoking psychiatric adverse events. Methods A 24-week, prospective, open-label study was conducted. At enrollment, we interviewed patients and reviewed their medical charts to collect demographic and clinical information. They were asked to complete self-report health questionnaires designed to measure various psychiatric symptoms and QOL at enrollment and 24 weeks later. Results Seventy-one patients were included in the study, 12 patients (16.9%) of whom discontinued LEV therapy due to serious adverse events including suicidality. The risk factor for premature withdrawal was a previous history of psychiatric diseases (odds ratio 4.59; 95% confidence interval, 1.22-17.32). LEV intake resulted in significant improvements in Beck Anxiety Inventory score (p<0.01) and some domains of the Symptom Checklist-90-Revised, such as somatization (p<0.05), obsessive-compulsiveness (p<0.05), depression (p<0.05), and anxiety (p<0.05). These improvements were not related to the occurrence of seizure freedom. The Quality of Life in Epilepsy Inventory-31 overall score and subscale scores, such as seizure worry (p<0.01), overall QOL (p<0.05), emotional well-being (p<0.05), energy-fatigue (p<0.05), and social function (p<0.05), also improved. Conclusions Adjunctive LEV in patients with DRE is likely to improve psychiatric symptoms and QOL. Clinicians should be well aware of the psychiatric histories of patients to prevent them from developing serious adverse events related to LEV.
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Hwang YH, Kim YW, Kim J, Kim YS, Park SP, Suh CK. Subacute Neurological Deterioration with Selective Axonal Injury in Patients with Acute Ischemic Stroke following Reperfusion of Middle Cerebral Artery Occlusion. Case Rep Neurol 2011; 3:199-202. [PMID: 22087099 PMCID: PMC3214670 DOI: 10.1159/000331450] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
To date, the long-term effects of reperfusion on the salvaged brain tissues have not been addressed in the literature. We report 4 cases presenting subacute neurological deteriorations with selective axonal injury following reperfusion therapies for acute ischemic stroke. Our case series based on 4 patients showed common features distinct from those of early reperfusion injury in that (1) the neurological symptoms developed after 1-2 months of reperfusion therapies, (2) these symptoms were accompanied by the subcortical white matter changes on brain MRI, and (3) these findings were mostly reversible with time. This suggests that axons in the reperfused brain may be vulnerable to further neurological injury.
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Kang DH, Kim YS, Park J, Hwang YH. Rescue forced suction thrombectomy using the reperfusion catheter of the Penumbra System for thromboembolism during coil embolization of ruptured cerebral aneurysms. Neurosurgery 2011. [DOI: 10.1227/neu.0b013e31822fefc4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Tsai HY, Liu HL, Hwang YH, Chen CC, Wan YL. SU-E-I-94: Survey of CT Image Quality and Patient Doses in Taiwan. Med Phys 2011. [DOI: 10.1118/1.3611668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Hwang YH, Song IB, Lee HK, Kim TW, Kim MS, Lim JH, Park BK, Yun HI. Pharmacokinetics and bioavailability of cefquinome in rabbits following intravenous and intramuscular administration. J Vet Pharmacol Ther 2011; 34:618-20. [PMID: 21615754 DOI: 10.1111/j.1365-2885.2011.01289.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Ahn YT, Hwang YH, Shin HS. Application of PTFE membrane for ammonia removal in a membrane contactor. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2011; 63:2944-2948. [PMID: 22049723 DOI: 10.2166/wst.2011.141] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The feasibility of a membrane contactor system for ammonia removal was studied. The mass transfer coefficient was used to quantitatively compare the effect of various operation conditions on ammonia removal efficiency. Effective removal of ammonia was possible with a Polytetrafluoroethylene (PTFE) membrane contactor system at all tested conditions. Among the various operation parameters, contact time and solution pH showed significant effect on the ammonia removal mechanism. The overall ammonia removal rate was not affected by influent suspended solution concentration unlike other pressure driven membrane filtration processes. Also the osmotic distillation phenomena which deteriorate the mass transfer efficiency can be minimized by preheating of influent wastewater. A membrane contactor system can be a possible alternative to treat high strength nitrogen wastewater by optimizing operation conditions such as stripping solution flow rate, influent wastewater temperature, and influent pH.
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Park SP, Song HS, Hwang YH, Lee HW, Suh CK, Kwon SH. Differential effects of seizure control and affective symptoms on quality of life in people with epilepsy. Epilepsy Behav 2010; 18:455-9. [PMID: 20591744 DOI: 10.1016/j.yebeh.2010.05.021] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2010] [Revised: 05/27/2010] [Accepted: 05/28/2010] [Indexed: 02/07/2023]
Abstract
OBJECTIVE The purpose of the study was to delineate how affective symptoms (AS) influence quality of life (QOL) for individuals with drug-refractory epilepsy (DRE) and those with well-controlled epilepsy (WCE) independently. METHODS All subjects participating in the study were asked to complete reliable and validated self-report health questionnaires, including AS, measured with the Korean versions of the Beck Depression Inventory, Beck Anxiety Inventory, and Quality of Life in Epilepsy Inventory-31 (QOLIE-31). We examined predictors of QOLIE-31 scores among the various demographic and clinical factors. We compared the effects of AS on QOL between patients with DRE and those with WCE and investigated the differential effects of seizure control and AS on QOL. RESULTS Two hundred forty-nine patients with DRE or WCE were included in the study. The strongest predictor of QOL was AS, followed by seizure control and MRI abnormality. Affective symptoms had almost two times the effect of seizure control and six times the effect of MRI abnormality. Poorest QOL was noted in patients with DRE with AS, followed by those with WCE with AS, DRE without AS, and WCE without AS. CONCLUSION The major determinant of QOL in patients with epilepsy is AS rather than DRE or WCE status.
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Lim HW, Song HS, Hwang YH, Lee HW, Suh CK, Park SP, Kwon SH. Predictors of suicidal ideation in people with epilepsy living in Korea. J Clin Neurol 2010; 6:81-8. [PMID: 20607047 PMCID: PMC2895228 DOI: 10.3988/jcn.2010.6.2.81] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2010] [Revised: 03/09/2010] [Accepted: 03/10/2010] [Indexed: 11/17/2022] Open
Abstract
Background and Purpose The risk of suicide or suicide attempts is reported higher in people with epilepsy (PWE) than in the general population. Although epileptic, psychiatric, and psychosocial factors are known risk factors for suicide or suicide attempt, no studies have evaluated the predictors of the severity of suicidal ideation-which is a warning sign for suicide attempts-in PWE. Therefore, we measured the severity of suicidal ideation and its risk factors. Methods Consecutive PWE who were medicated with antiepileptic drugs (AEDs) and attended epilepsy clinic were included in the study. The subjects completed self-reported questionnaires, which included the Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), Symptom Checklist-90-Revised (SCL-90-R), and Scale for Suicide Ideation-Beck (SSI-Beck). We compared the patients' demographic and clinical variables, and BDI, BAI, and SCL-90-R scores with their SSI-Beck score, and used our findings to determine the predictors for suicidal ideation. Results In total, 257 PWE were enrolled in the study. SSI-Beck scores correlated strongly with several seizure-related variables, duration of education, IQ, BDI and BAI scores, and nine domains of the SCL-90-R questionnaire. However, the strongest predictor for suicidal ideation was BDI score (β=0.41, p<0.001), followed by several SCL-90-R domains, such as obsessive-compulsive (β=-0.39, p<0.001), depression (β=0.38, p<0.001), hostility (β=0.22, p=0.002), paranoid ideation (β=0.17, p=0.01), and IQ (β=-0.10, p=0.017). These variables explained 59% of the variance in the SSI-Beck score. The seizure-related variables that influenced the BDI score were seizure frequency, duration of education, MRI abnormality, and number of AEDs. However, these variables explained only 18% of the variance in the BDI score. Conclusions Major risk factors for suicidal ideation in PWE were depressive and psychiatric symptoms rather than seizure-related variables. Therefore, clinicians should focus on screening for depression and other psychiatric problems and treat them appropriately in order to reduce suicidal behavior in PWE. Since seizure-related variables also exhibited a minor role in determining depressive symptoms, stronger seizure-related risk factors for depression should be sought, such as seizure severity or psychosocial factors, to minimize suicidal behavior.
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Park J, Hwang YH, Kim Y. Extended superciliary approach for middle cerebral artery embolectomy after unsuccessful endovascular recanalization therapy: technical note. Neurosurgery 2010; 65:E1191-4; discussion E1194. [PMID: 19934937 DOI: 10.1227/01.neu.0000351783.00831.bb] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE Although an intra-arterial mechanical embolectomy extends the therapeutic time window for restoration of the cerebral blood flow, its suboptimal recanalization rate also necessitates a salvage procedure if the patient is still within the therapeutic time window. As such, a surgical embolectomy can be performed in a rapid and less invasive manner for an acute middle cerebral artery (MCA) occlusion. The technical details of this procedure are discussed and demonstrated. METHODS Four patients with an acute MCA occlusion were treated using a novel surgical embolectomy technique after unsuccessful intra-arterial mechanical recanalization therapy. Unique to the proposed surgical technique are a laterally extended superciliary approach, small (3-mm) arteriotomy, and closure of the arteriotomy using an aneurysm clip after removal of the intravascular embolus. RESULTS Occluded MCAs were successfully recanalized using the present technique, and the operative time from skin incision to recanalization was 1 to 1.5 hours in each patient. One to 3 arteriotomies were made in each patient. Six of the 8 arteriotomies in the present series were closed using an aneurysm clip, whereas the other 2 arteriotomies were repaired using microsutures. Postoperative angiograms demonstrated patent MCAs without remarkable clip-induced stenosis. The successful recanalization provided considerable neurological improvement in all patients without procedural complications, except for 1 patient with a fatal putaminal hemorrhage resulting from a reperfusion injury. CONCLUSION A laterally extended superciliary approach and clip application for arteriotomy closure enable a surgical embolectomy to become a rapid and less invasive procedure.
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Kang DH, Kim YS, Hwang YH. Directly Retrieved Entire Clot from Forced Suction Thrombectomy Using the Penumbra System in Acute Middle Cerebral Artery Occlusion. Neurointervention 2010. [DOI: 10.5469/neuroint.2010.5.1.40] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Hwang YH, Kim DG, Ahn YT, Moon CM, Shin HS. Fate of nitrogen species in nitrate reduction by nanoscale zero valent iron and characterization of the reaction kinetics. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2010; 61:705-712. [PMID: 20150707 DOI: 10.2166/wst.2010.895] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
This study investigates the fate of nitrogen species during nitrate reduction by nanoscale zero valent iron (NZVI) as well as the related kinetics. The NZVI used for the experiments was prepared by chemical reduction without a stabilizing agent. The pseudo first order kinetic constant of nitrate reduction at 30 degrees C with an NZVI/nitrate ratio of 1.25:1, which were the reference conditions of this study, was 4.08 h(-1) (R(2)=0.955). A nitrogen mass balance was established by quantitative analysis of aqueous-phase and gas-phase nitrogen species. The results confirm that the nitrate was converted to ammonium ion, that ammonia stripping subsequently occurred under a strong alkaline condition, and that the total amount of aqueous nitrogen was consequently reduced. The nitrate reduction rate also increased with a lower pH and a higher temperature when microscale ZVI was used. However, in contrast to the reaction by microscale ZVI, the nitrate reduction rate by NZVI was higher for an unbuffered condition, possibly due to the abundance of surface atoms and the smaller size.
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Yang HS, Ali MS, Jeong JY, Moon SH, Hwang YH, Park GB, Joo ST. Properties of duck meat sausages supplemented with cereal flours. Poult Sci 2009; 88:1452-8. [PMID: 19531717 DOI: 10.3382/ps.2008-00361] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Jeong JY, Hur SJ, Yang HS, Moon SH, Hwang YH, Park GB, Joo ST. Discoloration characteristics of 3 major muscles from cattle during cold storage. J Food Sci 2009; 74:C1-5. [PMID: 19200079 DOI: 10.1111/j.1750-3841.2008.00983.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Discoloration characteristics of 3 major muscles (LD, Longissimus dorsi; PM, Psoas major; SM, Semimemebranosus) from Korean native cattle (Hanwoo) were monitored during 7 d of cold storage at 4 degrees C. The muscles were obtained from 12 Hanwoo carcasses at 24 h postmortem. Meat color (CIE L*, a*, b*), myoglobin (Mb) concentration, chemical form, metmyoglobin (MetMb) reducing ability (MRA), mitochondria concentration, and thiobarbituric acid reactive substance (TBARS) were measured at 1, 3, 5, and 7 d of storage. Although there were no significant differences in CIE a* and b*-values between the 3 muscles at day 1, the values of PM muscle were significantly (P < 0.05) lower than those of LD and SM muscles at day 5 and 7. PM muscle showed a rapid decrease in the oxymyoglobin (OxyMb) and an increase in MetMb, which resulted in a significantly (P < 0.05) higher percentage of MetMb in PM muscle compared to LD and SM muscles. Also, the Mb and mitochondria concentration of PM muscle was significantly (P < 0.05) higher than those of LD and SM muscles. However, there were no significant differences in MRA, pH, or TBARS between the 3 muscles during 7 d of cold storage. It was concluded that rapid discoloration (that is, MetMb accumulation) in PM muscle of Hanwoo could be due to its higher contents of Mb and mitochondria.
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Ali MS, Yang HS, Jeong JY, Moon SH, Hwang YH, Park GB, Joo ST. Effect of chilling temperature of carcass on breast meat quality of duck. Poult Sci 2008; 87:1860-7. [PMID: 18753455 DOI: 10.3382/ps.2007-00194] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
An experiment was carried out to investigate whether variations in chill water temperature affect muscle shortening and meat quality in duck breast. Three chill water temperatures were applied to duck carcasses at 20 min postmortem for 30 min, including in ice water at 0 degrees C, in cold water at 10 degrees C, and in water at 20 degrees C. Results revealed that carcass temperatures were different (P < 0.05) at 50 and 120 min of postmortem with lower temperatures at the 0 degrees C treatment (P < 0.05). The pH over the first 24 h postmortem was not different (P > 0.05) among treatments, with the exception of 50 min postmortem. The pH of breast meat in the 0 degrees C treatment was higher (P < 0.05) than that of 20 degrees C treatment at 50 min postmortem (just after chilling). No other differences (P > 0.05) in pH existed among treatments. Drip loss, cooking loss, and moisture content were not different for breast meat samples that were chilled at different temperatures. Differences (P < 0.05) were found in CIE (L, a, and b) color values. Lightness (L) increased, whereas redness (a) decreased as the chill water temperature increased. Lower yellowness (b) was found in the breast meat samples at the 10 degrees C chill water temperature. However, shear force, sarcomere length, and protein solubility were not different (P > 0.05) among the breast meat samples chilled at different chill water temperatures. It may be concluded that chilling duck carcasses at different temperature ranges from 0 to 20 degrees C did not influence muscle shortening or meat quality, except in regard to breast meat color.
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Wang IJ, Hsieh WS, Guo YL, Jee SH, Hsieh CJ, Hwang YH, Chen PC. Neuro-mediators as predictors of paediatric atopic dermatitis. Clin Exp Allergy 2008; 38:1302-8. [PMID: 18510693 DOI: 10.1111/j.1365-2222.2008.03026.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND Attempts to identify predictors of atopic dermatitis (AD) have focused on genetic and immunologic factors. However, the role of neuro-mediators remains to be elucidated. OBJECTIVE To evaluate nerve growth factor (NGF) and vaso-active intestinal peptide (VIP) in predicting paediatric AD and assess their correlation with intrinsic and extrinsic types of AD. METHODS We performed a nested case-control study in the prospective Taiwan birth panel cohort study. Cord and maternal plasma and questionnaires were gathered at birth. During follow-up, we identified 40 available AD cases, which were matched to 80 unaffected controls chosen from this cohort. The concentrations of IgE, NGF, and VIP in cord and maternal plasma of these subjects were performed by ELISA. Receiver-operating characteristic (ROC) curves were generated to see how well each biomarker could predict AD. RESULTS The NGF levels were significantly higher in AD patients than controls (mean+/-SD: 65.47+/-44.45 vs. 49.21+/-12.18 pg/mL for cord plasma and 89.68+/-41.04 vs. 66.96+/-23.05 pg/mL for maternal plasma) (P<0.05). VIP levels were also higher but not statistically significant. Plasma NGF may be a better biomarker than IgE in detecting paediatric AD (area under the ROC curve=0.65 vs. 0.61 for cord plasma and 0.69 vs. 0.61 for maternal plasma). Maternal NGF levels were significantly higher in patients with both intrinsic (96.18+/-48.15 pg/mL) and extrinsic (86.18+/-37.23 pg/mL) types of AD compared with controls (66.96+/-23.05 pg/mL) (P<0.05). We assessed a significant correlation between self-reported stress during pregnancy and maternal NGF levels (r=0.22, P=0.02). CONCLUSION Our results suggest that NGF is a good alternative biomarker in predicting children with a risk of AD.
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Park SP, Hwang YH, Lee HW, Suh CK, Kwon SH, Lee BI. Long-term cognitive and mood effects of zonisamide monotherapy in epilepsy patients. Epilepsy Behav 2008; 12:102-8. [PMID: 17945539 DOI: 10.1016/j.yebeh.2007.08.002] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2007] [Revised: 08/01/2007] [Accepted: 08/01/2007] [Indexed: 11/25/2022]
Abstract
This study was a prospective, randomized, open-label investigation of the long-term effects of zonisamide (ZNS) monotherapy on cognition and mood of patients with epilepsy. Forty-three patients with epilepsy received ZNS, with final dose groups of 100, 200, 300, and 400mg/day. Cognitive and mood tests were done twice, at baseline and 1 year after starting medication. Nine patients were withdrawn prior to their follow-up tests. Three patients (33%) dropped out during the titration period because of cognitive and mood problems. Thirty-four patients completed follow-up neuropsychological tests. After 1 year of treatment, 16 patients (47%) complained of cognitive deficits. Only 5 patients (15%) experienced mood changes. Although ZNS decreased seizure frequency and EEG abnormalities and did not elicit significant mood changes, it had negative effects on several cognitive tests. Worse performance on delayed word recall, Trail Making Test Part B, and verbal fluency was related to dose. In conclusion, ZNS has adverse effects on cognition even after 1 year of treatment.
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Hwang YH, Seo JG, Lee HW, Park SP, Suh CK. Early Neurological Deterioration following Intravenous Recombinant Tissue Plasminogen Activator Therapy in Patients with Acute Lacunar Stroke. Cerebrovasc Dis 2008; 26:355-9. [DOI: 10.1159/000151638] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2007] [Accepted: 03/31/2008] [Indexed: 11/19/2022] Open
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Park SP, Kim SY, Hwang YH, Lee HW, Suh CK, Kwon SH. Long-term efficacy and safety of zonisamide monotherapy in epilepsy patients. J Clin Neurol 2007; 3:175-80. [PMID: 19513128 PMCID: PMC2686939 DOI: 10.3988/jcn.2007.3.4.175] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2007] [Accepted: 12/05/2007] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND AND PURPOSE Zonisamide (ZNS) is a useful antiepileptic drug with a broad therapeutic spectrum. However, there is limited information on the long-term use of ZNS as a monotherapy. This study investigated the long-term effects of ZNS as a monotherapy for the treatment of epilepsy. METHODS We retrospectively analyzed the records of epilepsy patients treated with ZNS monotherapy at our clinic. We identified outcomes for patients treated with ZNS monotherapy for a minimum of 6 months. Efficacy was quantified as the percentage change in seizure frequency, and safety was assessed by the frequency and types of adverse events. RESULTS Sixty patients who received ZNS for a minimum of 6 months were included. The mean duration of treatment was 19.8 months (range, 6-37 months), and the mean ZNS dosage was 255 mg/day (range, 100-500 mg/day). Twenty-seven patients (45%) were seizure-free, and an additional 20 patients (33%) had above 50% seizure frequency reduction at the last follow-up visit. Partial seizures with or without secondary generalization and generalized seizures were well controlled by ZNS, whereas complex partial seizures were not. Forty-eight patients (80%) reported mild-to-moderate adverse events, including memory loss (35%), attention deficit (27%), and weight loss (20%). CONCLUSIONS Long-term ZNS monotherapy is effective at treating a broad spectrum of seizure disorders, except complex partial seizures. However, a specific adverse event, such as cognitive impairment, is common and long-lasting.
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Park J, Hwang YH, Baik SK, Kim YS, Park SH, Hamm IS. Angiographic examination of spontaneous putaminal hemorrhage. Cerebrovasc Dis 2007; 24:434-8. [PMID: 17878724 DOI: 10.1159/000108433] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2007] [Accepted: 05/22/2007] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND This study was carried out to examine indications for angiographic evaluation in the case of spontaneous putaminal hemorrhage. METHODS Angiographic examinations were performed on 62 consecutive adults with spontaneous putaminal hemorrhage without remarkable subarachnoid hemorrhage. Most patients were evaluated using conventional catheter angiography except for hypertensive patients over the age of 60 who underwent a magnetic resonance angiogram or a computed tomography angiogram. Computed tomography and clinical factors such as age and hypertension were correlated with the angiographic findings. RESULTS Nine of the 62 patients (15%) exhibited angiographic abnormalities, including middle cerebral artery aneurysm (n = 1), arteriovenous malformations (n = 3), moyamoya disease (n = 2), and the moyamoya phenomenon associated with a proximal middle cerebral artery occlusion (n = 3). The angiographic yield was significantly higher (1) among patients at or below the median age of 55 compared with those above (9/33, 27%, versus 0/29, 0%; p < 0.01), and (2) among patients without hypertension compared with those with hypertension (5/9, 56%, versus 4/53, 8%; p < 0.01). CONCLUSIONS Although our data could be biased due to the patient selection procedure, they suggest that angiographic evaluation is highly useful for spontaneous putaminal hemorrhage regardless of volume and shape of the hematomas, excepting hypertensive patients over 55 years of age.
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Kim SY, Hwang YH, Lee HW, Suh CK, Kwon SH, Park SP. Cognitive impairment in juvenile myoclonic epilepsy. J Clin Neurol 2007; 3:86-92. [PMID: 19513297 PMCID: PMC2686860 DOI: 10.3988/jcn.2007.3.2.86] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2007] [Accepted: 05/31/2007] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND AND PURPOSE Cognitive impairments are frequent consequences of epilepsy, with intellectual ability reportedly being lower in patients with idiopathic generalized epilepsies than in the general population. However, neuropsychological investigations have been rarely performed in patients with juvenile myoclonic epilepsy (JME). We aimed to quantify the cognitive function in JME patients using various neuropsychological tests. METHODS We compared cognitive function in 27 JME patients with that in 27 healthy volunteers using tests examining cognitive performance, such as the verbal and visual memory, frontal function, attention, IQ score, and mood. In the JME group, we examined risk factors for cognitive function such as age, sex, family history, education level, age at seizure onset, seizure frequency, EEG abnormality, disease duration, and previous intake of antiepileptic drugs. RESULTS Verbal learning was significantly lower in JME patients than in controls, and attention and verbal fluency were impaired in JME patients compared with controls. However, general intellectual ability and mood did not differ between the groups. Early onset of seizure and long duration of disease were closely related to impaired cognitive function. CONCLUSIONS JME patients may exhibit impaired cognitive function, in terms of memory and execution, despite having normal intelligence and mood.
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