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1.
Medicina (Kaunas) ; 57(5)2021 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-34069555

RESUMEN

Background and Objectives: Endovascular thrombectomy (EVT is an emerging gold standard treatment for acute cerebral infarction and may allow functional improvement after subacute cerebral infarction. However, the long-term functional benefits of EVT in patients with moderate to severe disability remain unclear. We investigated the effects of EVT on the activities of daily living (ADL), handicap, gait, and eating in patients with middle cerebral artery (MCA) occlusion who exhibited moderate to severe disability (score of 3-5 on the modified Rankin scale (mRS)) due to stroke, up to six months after onset. Materials and Methods: This retrospective longitudinal case-control study assessed 45 patients with MCA occlusion who exhibited moderate to severe disability (mRS score ≥ 3): 15 underwent EVT and 30 served as controls. Clinical assessments were conducted at two weeks (12-16 days), four weeks (26-30 days), and six months (180-210 days) after stroke onset. Functional assessments comprised the Korean version of the modified Barthel index (MBI), mRS, functional ambulation category (FAC), and dysphagia outcome severity scale (DOSS) to assess disability, handicap, gait, and eating. Results: The MBI, mRS, FAC, and DOSS scores all improved significantly (all p < 0.05) in the EVT group, compared to the controls. Conclusions: EVT has favorable effects on performing routine ADL, the handicap itself, walking, and eating. Therefore, EVT is recommended for patients with acute MCA occlusion, including those with severe disability at the initial assessment.


Asunto(s)
Procedimientos Endovasculares , Accidente Cerebrovascular , Actividades Cotidianas , Estudios de Casos y Controles , Humanos , Infarto de la Arteria Cerebral Media/cirugía , Estudios Retrospectivos , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/cirugía , Trombectomía , Resultado del Tratamiento
2.
Inorg Chem ; 56(15): 9369-9375, 2017 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-28741956

RESUMEN

A novel lithium-rich transition metal selenite, Li13Mn(SeO3)8, that is composed of a Jahn-Teller distortive cation, Mn3+, in the high spin d4 state, and a second-order Jahn-Teller (SOJT) distortive lone pair cation, Se4+, has been synthesized via hydrothermal and high temperature solid state reactions. The selenite is classified as a molecular compound consisting of MnO6 octahedra, SeO3 trigonal pyramids, and Li+ cations. Considering the Li-O interactions, the structure of Li13Mn(SeO3)8 may be described as a pseudo-three-dimensional framework as well. The title compound is thermally stable up to 500 °C and starts decomposing above the temperature attributable to the volatilization of SeO2. While the MnO6 octahedra in Li13Mn(SeO3)8 exhibit six identical Mn-O bond distances at room temperature due to the dynamic Jahn-Teller effect, a clear elongation of two Mn-O bonds along a specific direction is observed at 100 K. A series of isostructural selenites with different transition metals, i.e., Li13M(SeO3)8 (M = Sc, Cr, and Fe), have been also successfully obtained in phase pure forms using similar synthetic methods. Magnetic properties, spectroscopic characterizations, and local dipole moments calculations for all the synthesized selenites are presented.

3.
Nanotechnology ; 28(43): 435102, 2017 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-28783035

RESUMEN

In this study, a novel type of hyaluronic acid (HA)-decorated nanostructured lipid carrier (NLC) was prepared and investigated as a light-triggered drug release and combined photothermal-chemotherapy for cancer treatment. Polyhedral gold nanoparticles (Au NPs) with an average size of 10 nm were synthesized and co-encapsulated with doxorubicin (DOX) in the matrix of NLCs with a high drug loading efficiency (above 80%). HA decoration was achieved by the electrostatic interaction between HA and CTAB on the NLC surface. A remarkable temperature increase was observed by exposing the Au NP-loaded NLCs to an NIR laser, which heated the samples sufficiently (above 40 °C) to kill tumor cells. The entrapped DOX exhibited a sustained, stepwise NIR laser-triggered drug release pattern. The biocompatibility of the NLCs was investigated by MTT assay and the cell viability was maintained above 85%, even at high concentrations. The intracellular uptake of free DOX and entrapped DOX, observed by confocal microscopy, revealed two distinct uptake mechanisms, i.e. passive diffusion and endocytosis, respectively. In particular, internalization of the HA-Au-DOX-NLCs was more extensively enhanced than the Au-DOX-NLCs, which was attributed to HA-CD44 receptor-mediated endocytosis. Meanwhile, the internalized NLCs successfully escaped from the lysosomes, increasing the intracellular DOX. The HA-Au-DOX-NLCs IC50 value decreased from 2.3 to 0.6 µg ml-1 with NIR irradiation at 72 h, indicating the excellent synergistic antitumor effect of photothermal-chemotherapy. The photothermal ablation was further confirmed by a live/dead cell staining assay. Thus, a combined photothermal-chemotherapy approach has been proposed as a promising strategy for cancer treatment.


Asunto(s)
Antibióticos Antineoplásicos/farmacología , Neoplasias de la Mama/terapia , Doxorrubicina/farmacología , Ácido Hialurónico/química , Nanopartículas del Metal/administración & dosificación , Nanoestructuras/administración & dosificación , Animales , Antibióticos Antineoplásicos/química , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Cetrimonio , Compuestos de Cetrimonio/química , Preparaciones de Acción Retardada , Doxorrubicina/química , Composición de Medicamentos/métodos , Liberación de Fármacos , Femenino , Oro/química , Calor , Humanos , Rayos Infrarrojos , Cinética , Lípidos/química , Células MCF-7 , Nanopartículas del Metal/química , Nanopartículas del Metal/ultraestructura , Ratones Endogámicos BALB C , Nanoestructuras/química , Nanoestructuras/ultraestructura , Ensayos Antitumor por Modelo de Xenoinjerto
4.
Inorg Chem ; 54(10): 5032-8, 2015 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-25915517

RESUMEN

Four new stoichiometrically equivalent quaternary scandium selenites, ASc(SeO3)2 (A = Na, K, Rb, and Cs) have been hydrothermally synthesized using A2CO3, Sc(NO3)3·xH2O (or ScO3), and SeO2 as starting materials. All four materials share similar bond networks that are composed of corner-shared distorted ScO6 octahedra and SeO3 trigonal pyramids. However, each material reveals different frameworks and centricities. Detailed structural analysis suggests that the structural variation is attributed to the difference in size and subsequent coordination number for the alkali metal cations. Powder second-harmonic generation (SHG) measurements on noncentrosymmetric (NCS) RbSc(SeO3)2 show that the compound has an SHG efficiency similar to that of (NH4)H2PO4. The observed SHG efficiency is due to the remaining net polarization after cancellation of oppositely aligned moments for SeO3 and ScO6 groups. Thorough characterizations such as spectroscopic, thermal, and elemental analyses for the new materials are presented as are dipole moment and out-of-center distortion calculations.

5.
Inorg Chem ; 53(13): 7040-6, 2014 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-24918773

RESUMEN

Both single crystals and pure bulk phases of three new scandium selenium/tellurium oxides, Sc2(SeO3)2(SeO4), Sc2(TeO3)(SeO3)(SeO4), and Sc2(TeO3)3, have been synthesized through hydrothermal and solid-state reactions. X-ray diffractions were used to determine the structures and confirm the phase purities of the reported materials. Isostructural Sc2(SeO3)2(SeO4) and Sc2(TeO3)(SeO3)(SeO4) reveal three-dimensional frameworks with ScO7 pentagonal bipyramids, SeO3 (and TeO3) trigonal pyramids, and SeO4 tetrahedra. A novel ternary scandium tellurite, Sc2(TeO3)3, also shows a three-dimensional framework that is composed of ScO6 octahedra, ScO7-capped octahedra, and TeO3 trigonal pyramids. All three materials accommodate local asymmetric coordination moieties owing to the lone pairs on Se(4+) and Te(4+) cations. The effect of coordination environments of constituent cations on the frameworks, dimensionalities, and centricities of products is discussed. Thorough characterizations including elemental analyses, infrared and UV-vis diffuse reflectance spectroscopies, thermal analyses, and dipole moment calculations for the reported materials are reported. Crystal data: Sc2(SeO3)2(SeO4), monoclinic, space group P21/c (No. 14), a = 6.5294(2) Å, b = 10.8557(4) Å, c = 12.6281(6) Å, ß = 103.543(3)°, V = 870.21(6) Å(3), and Z = 4; Sc2(TeO3)(SeO3)(SeO4), monoclinic, space group P21/c (No. 14), a = 6.5345(12) Å, b = 10.970(2) Å, c = 12.559(2) Å, ß = 102.699(10)°, V = 878.3(6) Å(3), and Z = 4; Sc2(TeO3)3, monoclinic, space group P21/n (No. 14), a = 5.2345(3) Å, b = 24.3958(15) Å, c = 6.8636(4) Å, ß = 106.948(2)°, V = 838.42(9) Å(3), and Z = 4.

6.
Inorg Chem ; 52(7): 4097-103, 2013 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-23506341

RESUMEN

Three new mixed metal selenium oxides materials, Bi2(SeO3)2(SeO4), Bi2(TeO3)2(SeO4), and Bi(SeO3)(HSeO3), have been synthesized by hydrothermal and solid-state reactions using Bi(NO3)3·5H2O, SeO2 (or TeO2), H2SeO4, and Bi2O3 as reagents. The reported materials have been structurally characterized by single crystal X-ray diffraction. While Bi2(SeO3)2(SeO4) and Bi2(TeO3)2(SeO4) are crystallographically centrosymmetric (CS), Bi(SeO3)(HSeO3) crystallizes in a noncentrosymmetric (NCS) space group. The isostructural Bi2(SeO3)2(SeO4) and Bi2(TeO3)2(SeO4) exhibit three-dimensional framework structures that are composed of BiO6, Se(4+)O3 (or Te(4+)O3), and Se(6+)O4 polyhedra. However, Bi(SeO3)(HSeO3) exhibits corrugated layers that are composed of BiO5, Se(4+)O3, and Se(4+)O2(OH) polyhedra. All three materials contain local asymmetric coordination environments attributable to the lone pairs on the Bi(3+), Se(4+), and/or Te(4+) cations. Powder second-harmonic generation (SHG) measurements on NCS Bi(SeO3)(HSeO3) using 1064 nm radiation indicate that the material has a SHG efficiency of approximately 20 times that of α-SiO2 and is not phase-matchable (type 1). The origin and magnitude of the SHG efficiency of Bi(SeO3)(HSeO3) is explained by determining the net direction of the polarizations arising from individual asymmetric polyhedra. Infrared spectroscopy, thermal analysis, elemental analysis, and dipole moment calculations for the reported materials are also presented.

7.
J Cerebrovasc Endovasc Neurosurg ; 25(1): 13-18, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36266236

RESUMEN

OBJECTIVE: Mechanical thrombectomy (MT) is an effective treatment for patients suffering from acute ischemic stroke secondary to large vessel occlusion. However, recanalization failure rates of interventions were about 20% in literature studies. We report our experience of unsuccessful MT with a focus on technical reasons. METHODS: From December 2010 to June 2021, six hundred eight patients with acute ischemic stroke due to large artery occlusion received MT using a stent retriever with or without an aspiration catheter in our institution. We divided the reasons for failure into six categories. We analyzed the reasons for failure by dividing our experience time into 3 periods. RESULTS: A total of 608 cases of thrombectomy for large vessel occlusion were identified in the study period. The successful recanalization rate was 90.4%. In most of the cases (20/57, 35%), the thrombus persisted despite several passes, and the second most common cause was termination of the procedure even after partial recanalization (10/57, 18%). Similar proportions of in-stent occlusion, distal embolization, and termination due to vessel rupture were observed. On analysis of three periods, the successful recanalization rate improved over time. CONCLUSIONS: MT fails due to various reasons, and intracranial artery stenosis is the main cause of MT failure. With the development of rescue techniques, the failure rate has gradually decreased. Further development of new devices and techniques could improve the recanalization rates.

8.
Curr Neurovasc Res ; 18(1): 78-84, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33632099

RESUMEN

INTRODUCTION: Susceptibility-Eeighted Imaging (SWI) enables visualization of thrombotic material in acute ischemic stroke. We analyzed the association between thrombus length on SWI and the success rate of recanalization in stent-retriever mechanical thrombectomy. METHODS: A retrospective study was performed on 128 patients with Middle Cerebral Artery (MCA) thrombus on pretreatment SWI. The patients were divided into 2 groups, the successful recanalization and the failed recanalization group. Thrombus visibility and location on SWI were compared to those on Maximum Intensity Projection (MIP) in Computed Tomography (CT) angiography. A comparative analysis was performed in terms of clinical and radiologic outcomes as well as complications with respect to multiple categories. RESULTS: No significant differences were noted in terms of baseline characteristics and clinical outcomes between the 2 groups. However, compared with the successful recanalization group, the failed recanalization group had a larger number of stent-retriever passages and a longer thrombus length (p = 0.027 and 0.014, respectively). Multivariate analyses revealed that a larger mean number of stent-retriever passages was a predictive factor for failure of recanalization (odds ratio [OR] 1.60; 95% confidence Interval [CI] 1.12-2.08; p = 0.04). Thrombus length (OR 9.91; 95% CI 3.89-13.87; p < 0.001) and atrial fibrillation (OR 5.38; 95% CI 1.51-9.58; p = 0.008) were separately associated with more than 3 stent-retriever passages. CONCLUSION: Thrombus length has been identified as a predictor of recanalization failure in mechanical thrombectomy. A significant decline in the success rate of recanalization was associated with longer thrombus length.


Asunto(s)
Trombosis Intracraneal/cirugía , Trombectomía , Anciano , Anciano de 80 o más Años , Angiografía Cerebral , Angiografía por Tomografía Computarizada , Femenino , Humanos , Trombosis Intracraneal/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Stents , Resultado del Tratamiento
9.
J Korean Neurosurg Soc ; 64(1): 30-38, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32759627

RESUMEN

OBJECTIVE: The Solitaire Platinum 4×40 mm stent retriever contains radiopaque markers with a long length. We evaluated the effect of Solitaire Platinum 4×40 mm stent retriever in Solumbra technique thrombectomy, and compared it with shorter Solitaire stent retrievers. METHODS: A total of 70 patients who underwent Solumbra technique thrombectomy with equal diameter (4 mm) and different length (40 vs. 20 mm) Solitaire stent retrievers were divided into two groups : the Solitaire Platinum 4×40 mm stent (4×40) group and the Solitaire FR 4×20 mm stent or Solitaire Platinum 4×20 mm stent (4×20) group. The clinical outcomes, Thrombolysis in Cerebral Infarction score, the first pass reperfusion status, and complications were evaluated and compared between the two groups. Multivariate analysis was performed to evaluate the predictive factors for reperfusion and complete reperfusion from the first pass. RESULTS: Higher first-pass reperfusion and complete reperfusion were achieved in the 4×40 group (68.0% and 48.0%) than in the 4×20 group (46.7% and 33.3%; p=0.004 and 0.007, respectively). In multivariate analysis, radiopaque device and longer stent retriever were correlated with first-pass reperfusion (p=0.014 and 0.008, respectively) and first-pass complete reperfusion (p=0.022 and 0.012, respectively). CONCLUSION: Our study demonstrated the usefulness of the Solitaire Platinum 4×40 mm stent retriever, which led to higher firstpass reperfusion and complete reperfusion rates than the Solitaire FR 4×20 mm stent or the Solitaire Platinum 4×20 mm stent, especially in Solumbra technique thrombectomy.

10.
J Korean Neurosurg Soc ; 59(5): 485-91, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27651867

RESUMEN

OBJECTIVE: The aims of the Korean Neuro-Trauma Data Bank System (KNTDBS) are to evaluate and improve treatment outcomes for brain trauma, prevent trauma, and provide data for research. Our purpose was to examine the mortality rates following traumatic brain injury (TBI) in a retrospective study and to investigate the sociodemographic variables, characteristics, and causes of TBI-related death based on data from the KNTDBS. METHODS: From 2010 to 2014, we analyzed the data of 2617 patients registered in the KNTDBS. The demographic characteristics of patients with TBI were investigated. We divided patients into 2 groups, survivors and nonsurvivors, and compared variables between the groups to investigate variables that are related to death after TBI. We also analyzed variables related to the interval between TBI and death, mortality by region, and cause of death in the nonsurvivor group. RESULTS: The frequency of TBI in men was higher than that in women. With increasing age of the patients, the incidence of TBI also increased. Among 2617 patients, 688 patients (26.2%) underwent surgical treatment and 125 patients (4.7%) died. The age distributions of survivors vs. nonsurvivor groups and mortality rates according the severity of the brain injury, surgical treatment, and initial Glasgow Coma Scale (GCS) scores were statistically significantly different. Among 125 hospitalized nonsurvivors, 70 patients (56%) died within 7 days and direct brain damage was the most common cause of death (80.8%). The time interval from TBI to death differed depending on the diagnosis, surgical or nonsurgical treatment, severity of brain injury, initial GCS score, and cause of death, and this difference was statistically significant. CONCLUSION: Using the KNTDBS, we identified epidemiology, mortality, and various factors related to nonsurvival. Building on our study, we should make a conscious effort to increase the survival duration and provide rapid and adequate treatment for TBI patients.

11.
J Cerebrovasc Endovasc Neurosurg ; 18(3): 253-257, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27847770

RESUMEN

An intracranial saccular aneurysm is uncommonly diagnosed in a patient with closed head trauma. We herein present a patient with delayed rebleeding of a cerebral aneurysm misdiagnosed as traumatic subarachnoid hemorrhage (SAH). A 26-year-old female visited our emergency department because of headache after a motorcycle accident. Brain computed tomography (CT) showed a right-side dominant SAH in Sylvian fissure. Although traumatic SAH was strongly suggested because of the history of head trauma, we performed a CT angiogram to exclude any vascular abnormalities. The CT angiogram showed no vascular abnormality. She was discharged after conservative treatment. One day after discharge, she returned to the emergency department because of mental deterioration. Brain CT showed diffuse SAH, which was dominant in the right Sylvian fissure. The CT angiogram revealed a right middle cerebral artery bifurcation aneurysm. During operation, a non-traumatic true saccular aneurysm was found. The patient recovered fully after successful clipping of the aneurysm and was discharged without neurologic deficit. Normal findings on a CT angiogram do not always exclude aneurysmal SAH. Follow-up vascular study should be considered in trauma patients who are highly suspicious of aneurysmal rupture.

12.
Korean J Spine ; 12(3): 235-8, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26512293

RESUMEN

Calcifying psuedoneoplasm of the spine is a rare non-neoplastic lesion of unknown origin. Radiologic and histologic manifestations are very variable and clinical symptoms include isolated pain, myelopathy, and radiculopathy. Surgical resection is the preferred option of treatment. This report describes three cases of calcifying pseudoneoplasm in the spine. The first case is a 77-year-old female with pain in both legs. The second case is a 67-year-old woman who presented as right leg pain. The third case is a 78-year-old woman with isolated back pain. The involved sites of each of cases were T12, L2-3, and L1, respectively. Surgical resection of the involved masses relieved symptoms.

13.
J Korean Neurosurg Soc ; 58(4): 321-7, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26587184

RESUMEN

OBJECTIVE: To determine whether the use of contrast enhancement (especially its extent) predicts malignant brain edema after intra-arterial thrombectomy (IAT) in patients with acute ischemic stroke. METHODS: We reviewed the records of patients with acute ischemic stroke who underwent IAT for occlusion of the internal carotid artery or the middle cerebral artery between January 2012 and March 2015. To estimate the extent of contrast enhancement (CE), we used the contrast enhancement area ratio (CEAR)-i.e., the ratio of the CE to the area of the hemisphere, as noted on immediate non-enhanced brain computed tomography (NECT) post-IAT. Patients were categorized into two groups based on the CEAR values being either greater than or less than 0.2. RESULTS: A total of 39 patients were included. Contrast enhancement was found in 26 patients (66.7%). In this subgroup, the CEAR was greater than 0.2 in 7 patients (18%) and less than 0.2 in the other 19 patients (48.7%). On univariate analysis, both CEAR ≥0.2 and the presence of subarachnoid hemorrhage were significantly associated with progression to malignant brain edema (p<0.001 and p=0.004), but on multivariate analysis, only CEAR ≥0.2 showed a statistically significant association (p=0.019). In the group with CEAR ≥0.2, the time to malignant brain edema was shorter (p=0.039) than in the group with CEAR <0.2. Clinical functional outcomes, based on the modified Rankin scale, were also significantly worse in patients with CEAR ≥0.2 (p=0.003). CONCLUSION: The extent of contrast enhancement as noted on NECT scans obtained immediately after IAT could be predictive of malignant brain edema and a poor clinical outcome.

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