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1.
Eur J Neurol ; 27(2): 343-351, 2020 02.
Article in English | MEDLINE | ID: mdl-31535427

ABSTRACT

BACKGROUND AND PURPOSE: The rate at which the chance of a good outcome of endovascular stroke therapy (EVT) decays with time when eligible patients are selected by baseline diffusion-weighted magnetic resonance imaging (DWI-MRI) and whether ischaemic core size affects this rate remain to be investigated. METHODS: This study analyses a prospective multicentre registry of stroke patients treated with EVT based on pretreatment DWI-MRI that was categorized into three groups: small [Diffusion-Weighted Imaging Alberta Stroke Program Early Computed Tomography Score (DWI-ASPECTS)] (8-10), moderate (5-7) and large (<5) cores. The main outcome was a good outcome at 90 days (modified Rankin Scale 0-2). The interaction between onset-to-groin puncture time (OTP) and DWI-ASPECTS categories regarding functional outcomes was investigated. RESULTS: Ultimately, 985 patients (age 69 ± 11 years; male 55%) were analysed. Potential interaction effects between the DWI-ASPECTS categories and OTP on a good outcome at 90 days were observed (Pinteraction  = 0.06). Every 60-min delay in OTP was associated with a 16% reduced likelihood of a good outcome at 90 days amongst patients with large cores, although no associations were observed amongst patients with small to moderate cores. Interestingly, the adjusted rates of a good outcome at 90 days steeply declined between 65 and 213 min of OTP and then remained smooth throughout 24 h of OTP (Pnonlinearity  = 0.15). CONCLUSIONS: Our study showed that the probability of a good outcome after EVT nonlinearly decreased, with a steeper decline at earlier OTP than at later OTP. Discrepant effects of OTP on functional outcomes by baseline DWI-ASPECTS categories were observed. Thus, different strategies for EVT based on time and ischaemic core size are warranted.


Subject(s)
Stroke , Aged , Aged, 80 and over , Alberta , Brain Ischemia/diagnostic imaging , Brain Ischemia/therapy , Diffusion Magnetic Resonance Imaging , Female , Humans , Male , Middle Aged , Prospective Studies , Stroke/diagnostic imaging , Stroke/therapy , Time-to-Treatment , Treatment Outcome
2.
J Phys Conf Ser ; 1001: 012013, 2018.
Article in English | MEDLINE | ID: mdl-31632451

ABSTRACT

Despite the large amount of information provided by direct numerical simulations of turbulent flows, their underlying dynamics remain elusive even in the most simple and canonical configurations. Most common approaches to investigate the turbulence phenomena do not provide a clear causal inference between events, which is essential to determine the dynamics of self-sustaining processes. In the present work, we examine the causal interactions between streaks, rolls and mean shear in the logarithmic layer of a minimal turbulent channel flow. Causality between structures is assessed in a non-intrusive manner by transfer entropy, i.e., how much the uncertainty of one structure is reduced by knowing the past states of the others. We choose to represent streaks by the first Fourier modes of the streamwise velocity, while rolls are defined by the wall-normal and spanwise velocity modes. The results show that the process is mainly unidirectional rather than cyclic, and that the log-layer motions are sustained by extracting energy from the mean shear which controls the dynamics and time-scales. The well-known lift-up effect is also identified, but shown to be of secondary importance in the causal network between shear, streaks and rolls.

3.
Int J Cosmet Sci ; 37(6): 567-73, 2015 Dec.
Article in English | MEDLINE | ID: mdl-25857400

ABSTRACT

OBJECTIVE: Arbutin is an effective agent for the treatment of melanin disorders. Arbutin may be converted to hydroquinone under conditions of high temperature, ultraviolet (UV) radiation and dilute acid. The aim of the current study was to develop an analytical method to determine the levels of arbutin and hydroquinone in whitening cosmetic products using high-performance liquid chromatography with photodiode array detection (HPLC-DAD). In addition, we investigated the effects of high temperature and pH on the decomposition of arbutin. METHODS: Samples extracted using two-step sonications were separated on a C18 column using a gradient mobile phase consisting of water and methanol. A 60-mm (40 µL) DAD cell was used to enhance the sensitivity of hydroquinone determination. Thermal decomposition of arbutin was evaluated at temperatures ranging from 60 to 120°C for 1-36 h. RESULTS: The method showed good linearity (R(2) ≥ 0.9997), precision (relative standard deviation, RSD < 5%) and acceptable extraction recovery (90-102.6%). The limits of quantitation for arbutin and hydroquinone were 0.0085 and 0.0119 µg mL(-1) , respectively. One sample of 21 cosmetic products tested contained arbutin at a concentration 1.61 g 100 g(-1) cream and 0.12 g 100 g(-1) cream of hydroquinone. Arbutin (327.18 ppm) decomposed after 6 h at 120°C and produced 10.73 ppm of hydroquinone. CONCLUSION: The developed method is simple to detect both arbutin and hydroquinone simultaneously in cosmetic products, at an adequate level of sensitivity. Notably, temperature and pH did not influence the decomposition of arbutin to hydroquinone in a 2% arbutin cream.


Subject(s)
Arbutin/analysis , Chromatography, High Pressure Liquid/methods , Hydroquinones/analysis , Skin Lightening Preparations/chemistry , Spectrophotometry, Ultraviolet/methods , Hydrogen-Ion Concentration , Temperature
4.
Eur J Neurol ; 20(5): 824-30, 2013 May.
Article in English | MEDLINE | ID: mdl-23294009

ABSTRACT

BACKGROUND: Both vertebrobasilar dolichoectasia (VBD) and cerebral microbleeds (CMBs) are related with the risk of intracerebral hemorrhage. We aimed to examine the relationship between the VBD and CMB in ischaemic stroke patients. METHODS: A consecutive series of 182 patients hospitalized because of ischaemic stroke or transient ischaemic attack (TIA), and who underwent gradient echo brain magnetic resonance imaging were retrospectively recruited from a prospective stroke registry. CMB locations were categorized into anterior and posterior circulation. Ectasia was defined as basilar artery (BA) diameter > 4.5 mm, and dolichosis, as either BA bifurcation above the suprasellar cistern or lateral to the margin of the clivus or dorsum sellae. Whether VBD is associated with CMB anywhere in the brain or in anterior or posterior circulation territories was analysed using binary and multinomial logistic regression models. RESULTS: Twenty-four subjects (13.2%) had VBD and 48 (26.4%) had CMBs. CMBs were more frequently observed in patients with VBD than without (66.7% vs. 20.3%, P < 0.001). VBD was significantly associated with CMBs in any location (crude odds ratio, 7.88; 95% confidence interval, 3.10-20.02), in the posterior circulation territory only (9.63; 2.60-34.94), and in both territories (9.25; 3.40-26.29), but not in the anterior circulation only (1.14; 0.009-11.20). These associations remained unchanged after adjusting for age, gender, hypertension, leukoaraiosis and stroke subtype. CONCLUSIONS: VBD in patients with ischaemic stroke or TIA is independently associated with CMBs, especially in the posterior circulation territory.


Subject(s)
Cerebral Hemorrhage/complications , Stroke/complications , Vertebrobasilar Insufficiency/complications , Aged , Cerebral Hemorrhage/pathology , Female , Humans , Ischemic Attack, Transient/complications , Ischemic Attack, Transient/pathology , Male , Middle Aged , Neuroimaging , Retrospective Studies , Risk Factors , Stroke/pathology , Vertebrobasilar Insufficiency/pathology
5.
Eur J Neurol ; 20(8): 1161-9, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23551657

ABSTRACT

BACKGROUND AND PURPOSE: We investigated the effect of celecoxib, a selective inhibitor of cyclo-oxygenase 2, in patients with intracerebral hemorrhage (ICH). METHODS: We conducted a multicenter, randomized, controlled, and open with blinded end-point trial of 44 Korean patients 18 years or older with ICH within 24 h of onset. The intervention group (n = 20) received celecoxib (400 mg twice a day) for 14 days. The control group (n = 24) received the standard medical treatment for ICH. The primary end-point was the number of patients with a change in the volume of perihematomal edema (PHE) from the 1st to the 7th ± 1 day (cut-off value, 20%). RESULTS: The time from onset to computed tomography scan slightly differed between groups (177 ± 160 min for control vs. 297 ± 305 min for the celecoxib group; P = 0.10). In the primary end-point analysis using cut-off values, there was a significant shift to reduced expansion of PHE in the celecoxib group (P = 0.005). With respect to the secondary end-points, there was also a significant shift to reduced expansion of ICH in the celecoxib group (P = 0.046). In addition, the expansion rate of PHE at follow-up tended to be higher in the control group than in the celecoxib group (90.6 ± 91.7% vs. 44.4 ± 64.9%; P = 0.058). CONCLUSIONS: In our small, pilot trial, administration of celecoxib in the acute stage of ICH was associated with a smaller expansion of PHE than that observed in controls.


Subject(s)
Brain Edema/drug therapy , Cerebral Hemorrhage/drug therapy , Cyclooxygenase 2 Inhibitors/therapeutic use , Pyrazoles/therapeutic use , Sulfonamides/therapeutic use , Aged , Aged, 80 and over , Brain Edema/pathology , Brain Edema/surgery , Celecoxib , Cerebral Hemorrhage/pathology , Cerebral Hemorrhage/surgery , Cyclooxygenase 2 Inhibitors/adverse effects , Disease Progression , Double-Blind Method , Endpoint Determination , Female , Glasgow Coma Scale , Glasgow Outcome Scale , Humans , Male , Middle Aged , Neurosurgical Procedures , Prospective Studies , Pyrazoles/adverse effects , Republic of Korea , Sulfonamides/adverse effects , Tomography, X-Ray Computed , Treatment Outcome
6.
AJNR Am J Neuroradiol ; 43(9): 1292-1298, 2022 09.
Article in English | MEDLINE | ID: mdl-35902120

ABSTRACT

BACKGROUND AND PURPOSE: Data on SAH after M2 mechanical thrombectomy are limited. We aimed to determine the prevalence of sulcal SAH after mechanical thrombectomy for M2 occlusion, its associated predictors, and the resulting clinical outcome. MATERIALS AND METHODS: The study retrospectively reviewed the data of patients with acute ischemic stroke who underwent mechanical thrombectomy for isolated M2 occlusion. The patients were divided into 2 groups according to the presence of sulcal SAH after M2 mechanical thrombectomy. Angiographic and clinical outcomes were compared. Multivariable analysis was performed to identify independent predictors of sulcal SAH and unfavorable outcome (90-day mRS, 3-6). RESULTS: Of the 209 enrolled patients, sulcal SAH was observed in 33 (15.8%) patients. The sulcal SAH group showed a higher rate of distal M2 occlusion (69.7% versus 22.7%), a higher of rate of superior division occlusion (63.6% versus 43.8%), and a higher M2 angulation (median, 128° versus 106°) than the non-sulcal SAH group. Of the 33 sulcal SAH cases, 23 (66.7%) were covert without visible intraprocedural contrast extravasation. Distal M2 occlusion (OR, 12.04; 95% CI, 4.56-35.67; P < .001), superior division (OR, 3.83; 95% CI, 1.43-11.26; P = .010), M2 angulation (OR, 1.02; 95% CI, 1.01-1.04; P < .001), and the number of passes (OR, 1.58; 95% CI, 1.22-2.09; P < .001) were independent predictors of sulcal SAH. However, covert sulcal SAH was not associated with an unfavorable outcome (P = .830). CONCLUSIONS: After mechanical thrombectomy for M2 occlusion, sulcal SAH was not uncommon and occurred more frequently with distal M2 occlusion, superior division, acute M2 angulation, and multiple thrombectomy passes (≥3). The impact of covert sulcal SAH was mostly benign and was not associated with an unfavorable outcome.


Subject(s)
Brain Ischemia , Ischemic Stroke , Stroke , Humans , Retrospective Studies , Thrombectomy/adverse effects , Thrombectomy/methods , Treatment Outcome , Stroke/epidemiology
7.
Acta Neurol Scand ; 123(5): 325-31, 2011 May.
Article in English | MEDLINE | ID: mdl-21426306

ABSTRACT

BACKGROUND: It has not been clarified whether the disparity in ischemic stroke outcome between populations is caused by ethnic and geographic differences or by variations in case mix. Propensity score matching (PSM) analysis can overcome some analytical problems but is rarely used in stroke outcome research. This study was to compare the ischemic stroke case-fatality between two PSM cohorts of Sweden and Korea. METHODS: Prognostic variables related to baseline characteristics and stroke care were included in our PSM model. Then, we selected 7675 Swedish and 1220 Korean patients with ischemic stroke from each stroke registers and performed one-to-one matching based on propensity scores of each patient. RESULTS: After PSM, all measured variables were well balanced in 1163 matched subjects, and the 90-day case-fatality was identical 6.2% (HR 0.997, 95%CI 0.905-1.099) in Sweden and Korea. CONCLUSIONS: No difference is found in the 90-day case-fatality in propensity score-matched Swedish and Korean patients with ischemic stroke.


Subject(s)
Brain Ischemia/mortality , Stroke/mortality , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Outcome Assessment, Health Care , Prognosis , Propensity Score , Registries , Republic of Korea/epidemiology , Risk Factors , Sweden/epidemiology , Treatment Outcome
8.
AJNR Am J Neuroradiol ; 42(11): 1986-1992, 2021 11.
Article in English | MEDLINE | ID: mdl-34475193

ABSTRACT

BACKGROUND AND PURPOSE: Data on adjunctive intra-arterial thrombolysis during mechanical thrombectomy for refractory thrombus are sparse. The aim of this study was to evaluate the efficacy and safety of local intra-arterial urokinase as an adjunct to mechanical thrombectomy for refractory large-vessel occlusion. MATERIALS AND METHODS: We retrospectively evaluated patients with acute ischemic stroke who underwent mechanical thrombectomy for anterior circulation large-vessel occlusion between January 2016 and December 2019. Patients were divided into 2 groups based on the use of intra-arterial urokinase as an adjunctive therapy during mechanical thrombectomy for refractory thrombus: the urokinase and nonurokinase groups. Herein, refractory thrombus was defined as the target occlusion with minimal reperfusion (TICI 0 or 1) despite >3 attempts with conventional mechanical thrombectomy. The baseline characteristics, procedural outcomes, and clinical outcome were compared between the 2 groups. RESULTS: One hundred fourteen cases of refractory thrombus were identified. A total of 45 and 69 patients were in the urokinase and the nonurokinase groups, respectively. The urokinase group compared with the nonurokinase group showed a higher rate of successful reperfusion (82.2% versus 63.8%, P = .034), with lower procedural times (54 versus 69 minutes, P = .137). The rates of good clinical outcome, distal embolism, and symptomatic intracranial hemorrhage were similar between the 2 groups. The use of intra-arterial urokinase (OR = 3.682; 95% CI, 1.156-11.730; P = .027) was an independent predictor of successful reperfusion. CONCLUSIONS: The use of local intra-arterial urokinase as an adjunct to mechanical thrombectomy may be an effective and safe method that provides better recanalization than the conventional mechanical thrombectomy for refractory thrombus in patients with embolic large-vessel occlusion.


Subject(s)
Brain Ischemia , Mechanical Thrombolysis , Stroke , Humans , Retrospective Studies , Stroke/diagnostic imaging , Stroke/surgery , Thrombectomy , Thrombolytic Therapy , Treatment Outcome
9.
AJNR Am J Neuroradiol ; 42(6): 1099-1103, 2021 06.
Article in English | MEDLINE | ID: mdl-33926897

ABSTRACT

BACKGROUND AND PURPOSE: The treatment paradigm for very large and giant aneurysms has recently changed to flow diversion, in light of the results of the Pipeline for Uncoilable or Failed Aneurysms trial. However, the effects of flow diversion were definitely unknown. We explored this topic and identified the predictors of such effects. MATERIALS AND METHODS: We retrospectively reviewed 51 patients with unruptured aneurysms admitted to our institution for flow diversion between February 2014 and August 2019. Patients were categorized into an effect group (no filling or remnant entry) and a no-effect group (subtotal or total filling). We evaluated the aneurysm size and shape, incorporation vessel, parent artery stenosis and curvature, stagnation of contrast medium within the aneurysm, use of balloon angioplasty, and intra-aneurysm thrombus as potential predictors of the effects of flow diversion. RESULTS: The effect group comprised 34 patients (66.7%, 34/51; no filling, 35.3%, 18/51; and remnant entry, 31.4%, 16/51). The no-effect group comprised 17 patients (33.3%, 17/51; subtotal filling, 29.4%, 15/51; and total filling, 3.9%, 2/51). An incorporation vessel and balloon angioplasty were independent risk factors for the no-effect group in multivariate logistic regression analyses (OR = 0.13 and 0.05; 95% confidence intervals, 0.02-0.62 and 0.00-0.32; P values, .021 and .004, respectively). CONCLUSIONS: Flow diversion is effective for very large and giant aneurysms, but the outcomes require further improvement. The results of this study show that an incorporated vessel and excessive balloon angioplasty might compromise flow diversion. This finding can help improve the outcomes of flow diversion.


Subject(s)
Intracranial Aneurysm , Embolization, Therapeutic , Endovascular Procedures , Humans , Intracranial Aneurysm/diagnostic imaging , Intracranial Aneurysm/surgery , Retrospective Studies , Stents , Treatment Outcome
10.
Diabetologia ; 53(3): 429-34, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20091021

ABSTRACT

AIMS/HYPOTHESIS: Admission hyperglycaemia is associated with a poor outcome in patients with ischaemic stroke. However, its prognostic effects after intracerebral haemorrhage (ICH) are still unclear. METHODS: We prospectively enrolled patients with ICH at 33 centres in Korea between October 2002 and March 2004. A total of 1,387 patients who had ICH and underwent brain computed tomography within 48 h of symptom onset were included in the study (n = 1,387). Clinical information and radiological findings were collected at admission. Glucose levels were examined in relation to early (up to 30 days after ictus) and long-term (after 30 days) mortality rates using Cox regression analysis. To eliminate short-term effects, long-term mortality rate analysis was performed on surviving patients for more than 30 days. RESULTS: The long-term mortality rate was 21.1% after a mean follow-up of 434.3 +/- 223.2 days and was found to increase significantly with glucose quartile (p < 0.001). Admission glucose level was an independent risk factor for early mortality (per mmol/l; adjusted HR 1.10 [95% CI 1.01-1.19]), but not for long-term mortality. Moreover, when analysis was restricted to patients without diabetes, glucose level was found to be an independent risk factor for post-ICH mortality (n = 1,119; adjusted HR 1.10 [95% CI 1.03-1.17]) and had marginal significance for early (p = 0.053) and long-term mortality (p = 0.09). CONCLUSIONS/INTERPRETATION: We found that admission glucose levels were associated with early mortality after ICH. In patients without diabetes, admission glucose levels were associated with long-term mortality. We therefore suggest that intensive lowering of glucose level should be further investigated in ICH patients.


Subject(s)
Blood Glucose/metabolism , Cerebral Hemorrhage/blood , Cerebral Hemorrhage/mortality , Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Korea , Male , Middle Aged , Proportional Hazards Models , Prospective Studies , Risk Factors , Treatment Outcome
11.
Acta Neurol Scand ; 121(1): 51-7, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19925528

ABSTRACT

OBJECTIVES: The aim of this study was to compare the effects of antihypertensive agents on cerebral blood flow (CBF) in hypertensive patients with previous ischemic stroke. MATERIALS AND METHODS: In this double-blind, multi-center, non-inferiority trial, 196 patients were randomized to cilnidipine 10-20 mg or losartan 50-100 mg once daily for 4 weeks. Baseline and follow-up CBF as measured by single photon emission computed tomography were obtained in 167. The primary endpoint was the global CBF change. The secondary endpoints were the CBF change in the hemisphere ipsilateral to the index stroke, non-impairment of global CBF and blood pressure (BP) reduction. RESULTS: Global CBF increased significantly in the cilnidipine arm (9.0 +/- 29.6%, P = 0.0071) and the losartan arm (11.4 +/- 31.4%, P = 0.0012), and these changes were not different between the two groups (P = 0.607). However, the estimated difference in percentage global CBF change between the two groups was -2.43% (97.5% CI, -13.06% to 8.21%), which crossed the predetermined non-inferiority margin of -8.6%. Ipsilesional hemispheric CBF change, non-impairment of global CBF and BP reduction were similar in the two groups. CONCLUSIONS: This trial failed to prove the non-inferiority of cilnidipine to losartan regarding global CBF change. Both the treatments, however, increase the global CBF despite BP lowering.


Subject(s)
Angiotensin II Type 1 Receptor Blockers/therapeutic use , Brain Ischemia/epidemiology , Calcium Channel Blockers/therapeutic use , Dihydropyridines/therapeutic use , Hypertension/drug therapy , Hypertension/epidemiology , Losartan/therapeutic use , Acute Disease , Aged , Brain/diagnostic imaging , Brain Ischemia/diagnostic imaging , Cerebrovascular Circulation/physiology , Double-Blind Method , Drug Administration Schedule , Female , Humans , Male , Middle Aged , Tomography, Emission-Computed, Single-Photon
12.
Eur J Neurol ; 16(12): 1331-5, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19832903

ABSTRACT

BACKGROUND AND PURPOSE: Intrahospital delay is the most serious obstacle in thrombolysis in acute ischaemic stroke (AIS). We implemented the pre-hospital notification system from the emergency medical information system in our metropolitan area to reduce intrahospital delay. METHODS: From October 2007, we implemented a 24-h hotline system between our stroke center and the Korean Emergency Medical Information System in Busan. We compared processing times and clinical outcomes amongst patients after using intravenous tissue type plasminogen activator (iv t-PA) with and without the hotline system. RESULTS: After the pre-hospital notification system was implemented, the rate of iv t-PA use increased from 6.5% to 14.3%. Time of onset in patients with pre-hospital notification was much longer than in patients without (121.5 +/- 34.8 min vs. 74.7 +/- 38.5 min, P < 0.01) notification but door-to-needle time was significantly reduced (28.9 +/- 11.4 min vs. 47.7 +/- 22.8 min, P < 0.01). However, there were no significant differences in 90-day clinical outcomes between the two groups. CONCLUSIONS: The pre-hospital notification system reduced intrahospital processing times which led to increased iv t-PA use after AIS. However, the improvement of clinical outcomes in thrombolysis might require organization of not only intrahospital processes but of outside processes such as the early recognition and rapid dispatch of patients with suspected AIS.


Subject(s)
Emergency Medicine/methods , Fibrinolytic Agents/administration & dosage , Hotlines , Stroke/drug therapy , Tissue Plasminogen Activator/administration & dosage , Delivery of Health Care/methods , Emergency Service, Hospital , Female , Humans , Male , Middle Aged , Time
13.
Neoplasma ; 56(2): 136-40, 2009.
Article in English | MEDLINE | ID: mdl-19239328

ABSTRACT

UNLABELLED: The Janus kinase 1 (JAK1) gene encodes a cytoplasmic tyrosine kinase that is noncovalently associated with a variety of cytokine receptors and plays a nonredundant role in cell proliferation, survival, and differentiation. The mutated forms of JAK1 often altered the activation of JAK1 and then changed the activation of JAK1/STAT pathways, and this may contribute to cancer development and progression. Thus, to investigate whether genetic mutations of JAK1 gene are associated in hepatocellular carcinoma (HCC) progression, we analyzed genetic alterations of JAK1 gene in 84 human HCCs by single-strand conformational polymorphism (SSCP) and direct sequencing. Of 24 exons of JAK1 gene, 12 exons were previously reported to have mutations, we searched genetic alteration of JAK1 in these exons. Overall, one missense mutation (1.2%) was found. In addition, 12 cases (14%) were found to have single nucleotide polymorphism (14%) in exon 14. Taken together, we found one novel missense mutation of JAK1 gene in hepatocellular carcinomas with some polymorphisms. Although the functional assessment of this novel mutant remains to be completed, JAK1 mutation may contribute to the tumor development in liver cancer. KEYWORDS: JAK1 gene, hepatocellular carcinoma, mutation.


Subject(s)
Carcinoma, Hepatocellular/genetics , Janus Kinase 1/genetics , Liver Neoplasms/genetics , Mutation , Adult , Aged , Aged, 80 and over , Female , Humans , Janus Kinase 1/physiology , Male , Middle Aged , Polymorphism, Single Nucleotide , Signal Transduction
14.
Neoplasma ; 56(4): 331-4, 2009.
Article in English | MEDLINE | ID: mdl-19469653

ABSTRACT

EphA3 is a component of the Eph/ephrin tyrosine kinase system, which participates in vasculature development. This receptor/ligand system is associated with various signaling pathways related to cell growth and viability, cytoskeletal organization, cell migration, and anti-apoptosis. Accumulated evidence suggests that aberrant regulation of EphA3 and its genetic alterations are implicated in the development and progression of various cancers. However, despite a high incidence of EphA3 over-expression, no such investigation has been performed in hepatocellular carcinoma. Thus, we investigated genetic alterations of the EphA3 gene in 73 cases of hepatocellular carcinoma by single-strand conformational polymorphism and sequencing. One novel D219V missense mutation was found in the extracellular domain of EphA3, and two genetic alterations in the intracellular sterile-alpha-motif (SAM) domain of EphA3 appeared to be polymorphisms. Although the functional assessments of this mutant are incomplete, it is believed that this novel EphA3 mutation may contribute to the development of hepatocellular carcinoma.


Subject(s)
Carcinoma, Hepatocellular/genetics , Liver Neoplasms/genetics , Mutation, Missense/genetics , Receptor Protein-Tyrosine Kinases/genetics , Adult , Aged , Aged, 80 and over , Carcinoma, Hepatocellular/pathology , Disease Progression , Female , Humans , Liver Neoplasms/pathology , Male , Middle Aged , Neoplasm Staging , Polymerase Chain Reaction , Polymorphism, Single-Stranded Conformational , Prognosis , Receptor, EphA3
16.
Eur J Neurol ; 15(12): 1324-31, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19049549

ABSTRACT

OBJECTIVE: To evaluate the impact of neurological and medical complications on 3-month outcomes in acute ischaemic stroke patients. METHODS: We prospectively investigated complications for all the consecutive acute ischaemic stroke patients admitted within 7 days from onset in four university hospitals during a 1-year period. Baseline data and 3-month outcomes were collected. Poor outcome was defined as a modified Rankin Scale score 3-6. RESULTS: A total of 1 254 patients were recruited: 264 (21.1%) and 303 (24.2%) patients experienced one or more neurological and medical complications, respectively. The most common complications were ischaemic stroke progression (17.1%) and pneumonia (12.0%). Of 1 233 patients with available 3-month outcomes, 34.9% had a poor outcome. Multivariate analysis revealed that neurological (odds ratio, 95% confidence interval; 5.47, 3.63-8.24) and medical (3.47, 2.30-5.23) complications were independent predictors of the poor outcome. For the individual complications, ischaemic stroke progression (7.48, 4.73-11.84), symptomatic hemorrhagic transformation (3.57, 1.33-9.54), pneumonia (4.44, 2.20-8.99), extracranial bleeding (4.45, 1.88-10.53), and urinary tract infection (2.72, 1.32-5.60) were independently associated with the poor outcome. CONCLUSION: Outcome after ischaemic stroke is adversely influenced by complications, especially ischaemic stroke progression, symptomatic hemorrhagic transformation, pneumonia, extracranial bleeding, and urinary tract infection. Interventions to prevent those complications might improve ischaemic stroke outcome.


Subject(s)
Brain Ischemia/complications , Stroke/complications , Acute Disease , Aged , Brain Ischemia/mortality , Cerebral Hemorrhage/etiology , Cerebral Hemorrhage/mortality , Diabetes Complications/mortality , Female , Hemorrhage/etiology , Hemorrhage/mortality , Humans , Hyperlipidemias/complications , Hyperlipidemias/mortality , Hypertension/complications , Hypertension/mortality , Incidence , Korea/epidemiology , Male , Middle Aged , Mortality/trends , Pneumonia/etiology , Pneumonia/mortality , Prognosis , Prospective Studies , Risk Factors , Smoking/adverse effects , Stroke/mortality , Time Factors , Urinary Tract Infections/etiology , Urinary Tract Infections/mortality
17.
Phys Rev Fluids ; 3(1)2018 Jan.
Article in English | MEDLINE | ID: mdl-31633075

ABSTRACT

A persistent problem in wall-bounded large-eddy simulations (LES) with Dirichlet no-slip boundary conditions is that the near-wall streamwise velocity fluctuations are overpredicted, while those in the wall-normal and spanwise directions are underpredicted. The problem may become particularly pronounced when the near-wall region is underresolved. The prediction of the fluctuations is known to improve for wall-modeled LES, where the no-slip boundary condition at the wall is typically replaced by Neumann and no-transpiration conditions for the wall-parallel and wall-normal velocities, respectively. However, the turbulence intensity peaks are sensitive to the grid resolution and the prediction may degrade when the grid is refined. In the present study, a physical explanation of this phenomena is offered in terms of the behavior of the near-wall streaks. We also show that further improvements are achieved by introducing a Robin (slip) boundary condition with transpiration instead of the Neumann condition. By using a slip condition, the inner energy production peak is damped, and the blocking effect of the wall is relaxed such that the splatting of eddies at the wall is mitigated. As a consequence, the slip boundary condition provides an accurate and consistent prediction of the turbulence intensities regardless of the near-wall resolution.

18.
AJNR Am J Neuroradiol ; 39(2): 331-336, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29242362

ABSTRACT

BACKGROUND AND PURPOSE: The Solitaire FR can be used not only as a tool for mechanical thrombectomy but also as a detachable permanent stent. Our aim was to assess the feasibility and safety of permanent stent placement with the Solitaire FR compared with other self-expanding stents for intracranial artery recanalization for acute ischemic stroke. MATERIALS AND METHODS: From January 2011 through January 2016, we retrospectively selected 2979 patients with acute ischemic stroke. Among them, 27 patients who underwent permanent stent placement (13 patients with the Solitaire FR [Solitaire group] and 14 patients with other self-expanding stents [other stent group]) were enrolled. The postprocedural modified TICI grade and angiographic and clinical outcomes were assessed. The safety and efficacy of permanent stent placement of the Solitaire FR for acute large-artery occlusion were evaluated. RESULTS: Stent placement was successful in all cases. Modified TICI 2b-3 reperfusion was noted in 84.6% of the Solitaire group and in 78.6% of the other stent group. Procedural time was significantly shorter in the Solitaire group than in the other stent group (P = .022). Shorter procedural time was correlated with favorable outcome (ρ = 0.46, P = .035). No significant differences were found in the modified TICI grade, NIHSS score, mRS, and hemorrhagic transformation rate between the 2 groups. The acute in-stent thrombosis rate at discharge was significantly lower when a glycoprotein IIb/IIIa inhibitor was injected during the procedure (P = .013). CONCLUSIONS: Permanent stent placement with the Solitaire FR compared with other self-expanding stents appears to be feasible and safe as a rescue tool for refractory intra-arterial therapy.


Subject(s)
Arterial Occlusive Diseases/therapy , Cerebral Revascularization/instrumentation , Endovascular Procedures/instrumentation , Stents , Stroke/therapy , Aged , Cerebral Revascularization/methods , Endovascular Procedures/methods , Feasibility Studies , Female , Humans , Male , Middle Aged , Retrospective Studies , Treatment Outcome
19.
Transplant Proc ; 48(3): 840-3, 2016 Apr.
Article in English | MEDLINE | ID: mdl-27234748

ABSTRACT

BACKGROUND: End-stage renal disease patients with autosomal dominant polycystic kidney disease may require native nephrectomy for various indications. However, the appropriate timing for nephrectomy in kidney transplantation and its effect on allograft survival have not been fully investigated. METHODS: We retrospectively analyzed 41 kidney transplant recipients with autosomal dominant polycystic kidney disease in whom transplantation was done simultaneously, after, or without native nephrectomy at Seoul St. Mary's hospital between January 1987 and February 2014. We divided patients into 2 groups based on when native nephrectomy was performed: simultaneously (group A, n = 13) and after or without nephrectomy (group B, n = 28), and compared perioperative outcomes, posttransplantation complications, and allograft survival rates. RESULTS: The mean operative time was significantly longer in group A than in group B (6.48 ± 1.84 vs 5.27 ± 0.84 hours; P = .048). The mean numbers of units required for intraoperative blood transfusions were also significantly higher in group A than in group B (3.66 ± 3.43 vs 0.75 ± 0.26 units; P = .018). However, there were no differences between groups in the incidence of acute rejection and other complications such as postoperative bleeding and infectious complications (P > .05, for all). The allograft survival rate also did not differ between groups (P > .05). CONCLUSIONS: Our study showed that patients undergoing simultaneous nephrectomy and kidney transplantations had clinical outcomes, in terms of complications and allograft survival, that were comparable to those in patients undergoing kidney transplantations with or without previous nephrectomy.


Subject(s)
Kidney Transplantation , Nephrectomy , Polycystic Kidney, Autosomal Dominant/surgery , Blood Transfusion/statistics & numerical data , Female , Graft Survival , Humans , Male , Middle Aged , Operative Time , Retrospective Studies
20.
Stroke ; 32(1): 94-9, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11136921

ABSTRACT

BACKGROUND AND PURPOSE: Although extracranial carotid artery disease (ECAD) is accepted as a risk factor for central nervous system (CNS) complications after coronary artery bypass graft (CABG) surgery, it remains to be clarified whether intracranial cerebral artery disease (ICAD) may also increase the risk. We conducted a prospective study to elucidate the relation between ICAD and CNS complications after CABG surgery. METHODS: We prospectively studied 201 patients undergoing nonemergency isolated CABG surgery during a 39-month period (from March 1995 to June 1998). Each patient was evaluated before surgery with neurological examination, transcranial Doppler, and carotid duplex ultrasonography. Magnetic resonance angiography was used to determine the presence and severity of ECAD and ICAD in patients with abnormal findings on clinical examination, carotid duplex ultrasonography, or transcranial Doppler. Patients were followed after surgery and evaluated for the development of CNS complications. Association between CNS complications and their potential predictors was analyzed. RESULTS: One hundred nine patients (54.2%) were found to have ECAD and/or ICAD. ECAD alone was found in 48 patients (23.9%), ICAD alone in 33 (16.4%), and both ECAD and ICAD in 28 (13.9%). Fifty-one patients (25.4%) had single or multiple CNS complications: 23 (11.4%) had delirium; 18 (9.0%) had hypoxic-metabolic encephalopathy; 7 (3.5%) had stroke; and 7 (3. 5%) had seizure. In multivariate analysis, ICAD was found to have an independent association with the development of CNS complications (prevalence OR, 2.28; 95% CI, 1.04 to 5.01) after controlling for covariates including age, occurrence of intraoperative events, and reoperation. The joint effect of ECAD and ICAD was also statistically significant and stronger than ICAD alone (prevalence OR, 3.87; 95% CI, 1.80 to 6.52). CONCLUSIONS: Our results suggest that ICAD may be an independent risk factor for CNS complications after CABG surgery. These results support pre-CABG evaluation of the intracranial arteries for the risk assessment of CABG surgery, at least in black and Asian patients, in whom there may be a higher prevalence of intracranial arterial stenosis.


Subject(s)
Brain Diseases/etiology , Coronary Artery Bypass/adverse effects , Postoperative Complications/etiology , Adult , Aged , Asian People , Carotid Arteries/diagnostic imaging , Cerebral Arterial Diseases/complications , Female , Humans , Korea , Logistic Models , Magnetic Resonance Angiography , Male , Middle Aged , Odds Ratio , Predictive Value of Tests , Prospective Studies , Risk Assessment , Risk Factors , Ultrasonography, Doppler, Transcranial
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