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1.
Nat Rev Mol Cell Biol ; 18(1): 5-17, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27703243

RESUMO

The narrow membrane necks formed during viral, exosomal and intra-endosomal budding from membranes, as well as during cytokinesis and related processes, have interiors that are contiguous with the cytosol. Severing these necks involves action from the opposite face of the membrane as occurs during the well-characterized formation of coated vesicles. This 'reverse' (or 'inverse')-topology membrane scission is carried out by the endosomal sorting complex required for transport (ESCRT) proteins, which form filaments, flat spirals, tubes and conical funnels that are thought to direct membrane remodelling and scission. Their assembly, and their disassembly by the ATPase vacuolar protein sorting-associated 4 (VPS4) have been intensively studied, but the mechanism of scission has been elusive. New insights from cryo-electron microscopy and various types of spectroscopy may finally be close to rectifying this situation.


Assuntos
Complexos Endossomais de Distribuição Requeridos para Transporte/química , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , ATPases Associadas a Diversas Atividades Celulares , Membrana Celular/metabolismo , Endossomos/metabolismo , HIV-1/metabolismo , Humanos , ATPases Vacuolares Próton-Translocadoras/metabolismo
2.
Cell ; 146(5): 732-45, 2011 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-21884935

RESUMO

Calcium/calmodulin-dependent kinase II (CaMKII) forms a highly conserved dodecameric assembly that is sensitive to the frequency of calcium pulse trains. Neither the structure of the dodecameric assembly nor how it regulates CaMKII are known. We present the crystal structure of an autoinhibited full-length human CaMKII holoenzyme, revealing an unexpected compact arrangement of kinase domains docked against a central hub, with the calmodulin-binding sites completely inaccessible. We show that this compact docking is important for the autoinhibition of the kinase domains and for setting the calcium response of the holoenzyme. Comparison of CaMKII isoforms, which differ in the length of the linker between the kinase domain and the hub, demonstrates that these interactions can be strengthened or weakened by changes in linker length. This equilibrium between autoinhibited states provides a simple mechanism for tuning the calcium response without changes in either the hub or the kinase domains.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/química , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Sequência de Aminoácidos , Animais , Cristalografia por Raios X , Holoenzimas/química , Holoenzimas/metabolismo , Humanos , Modelos Moleculares , Conformação Proteica , Estrutura Terciária de Proteína , Alinhamento de Sequência
3.
JAMA ; 330(9): 832-842, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37668619

RESUMO

Importance: Optimal blood pressure (BP) control after successful reperfusion with endovascular thrombectomy (EVT) for patients with acute ischemic stroke is unclear. Objective: To determine whether intensive BP management during the first 24 hours after successful reperfusion leads to better clinical outcomes than conventional BP management in patients who underwent EVT. Design, Setting, and Participants: Multicenter, randomized, open-label trial with a blinded end-point evaluation, conducted across 19 stroke centers in South Korea from June 2020 to November 2022 (final follow-up, March 8, 2023). It included 306 patients with large vessel occlusion acute ischemic stroke treated with EVT and with a modified Thrombolysis in Cerebral Infarction score of 2b or greater (partial or complete reperfusion). Interventions: Participants were randomly assigned to receive intensive BP management (systolic BP target <140 mm Hg; n = 155) or conventional management (systolic BP target 140-180 mm Hg; n = 150) for 24 hours after enrollment. Main Outcomes and Measures: The primary outcome was functional independence at 3 months (modified Rankin Scale score of 0-2). The primary safety outcomes were symptomatic intracerebral hemorrhage within 36 hours and death related to the index stroke within 3 months. Results: The trial was terminated early based on the recommendation of the data and safety monitoring board, which noted safety concerns. Among 306 randomized patients, 305 were confirmed eligible and 302 (99.0%) completed the trial (mean age, 73.0 years; 122 women [40.4%]). The intensive management group had a lower proportion achieving functional independence (39.4%) than the conventional management group (54.4%), with a significant risk difference (-15.1% [95% CI, -26.2% to -3.9%]) and adjusted odds ratio (0.56 [95% CI, 0.33-0.96]; P = .03). Rates of symptomatic intracerebral hemorrhage were 9.0% in the intensive group and 8.1% in the conventional group (risk difference, 1.0% [95% CI, -5.3% to 7.3%]; adjusted odds ratio, 1.10 [95% CI, 0.48-2.53]; P = .82). Death related to the index stroke within 3 months occurred in 7.7% of the intensive group and 5.4% of the conventional group (risk difference, 2.3% [95% CI, -3.3% to 7.9%]; adjusted odds ratio, 1.73 [95% CI, 0.61-4.92]; P = .31). Conclusions and Relevance: Among patients who achieved successful reperfusion with EVT for acute ischemic stroke with large vessel occlusion, intensive BP management for 24 hours led to a lower likelihood of functional independence at 3 months compared with conventional BP management. These results suggest that intensive BP management should be avoided after successful EVT in acute ischemic stroke. Trial Registration: ClinicalTrials.gov Identifier: NCT04205305.


Assuntos
Anti-Hipertensivos , Pressão Sanguínea , Estado Funcional , AVC Isquêmico , Trombectomia , Idoso , Feminino , Humanos , Pressão Sanguínea/efeitos dos fármacos , Hemorragia Cerebral/etiologia , AVC Isquêmico/tratamento farmacológico , AVC Isquêmico/cirurgia , Acidente Vascular Cerebral/terapia , Trombectomia/efeitos adversos , Trombectomia/métodos , Procedimentos Endovasculares , Doença Aguda , Resultado do Tratamento , Masculino , Anti-Hipertensivos/efeitos adversos , Anti-Hipertensivos/uso terapêutico
4.
BMC Bioinformatics ; 23(1): 48, 2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35062867

RESUMO

BACKGROUND: Fluorescence image analysis in biochemical science often involves the complex tasks of identifying samples for analysis and calculating the desired information from the intensity traces. Analyzing giant unilamellar vesicles (GUVs) is one of these tasks. Researchers need to identify many vesicles to statistically analyze the degree of molecular interaction or state of molecular organization on the membranes. This analysis is complicated, requiring a careful manual examination by researchers, so automating the analysis can significantly aid in improving its efficiency and reliability. RESULTS: We developed a convolutional neural network (CNN) assisted intelligent analysis routine based on the whole 3D z-stack images. The programs identify the vesicles with desired morphology and analyzes the data automatically. The programs can perform protein binding analysis on the membranes or state decision analysis of domain phase separation. We also show that the method can easily be applied to similar problems, such as intensity analysis of phase-separated protein droplets. CNN-based classification approach enables the identification of vesicles even from relatively complex samples. We demonstrate that the proposed artificial intelligence-assisted classification can further enhance the accuracy of the analysis close to the performance of manual examination in vesicle selection and vesicle state determination analysis. CONCLUSIONS: We developed a MATLAB based software capable of efficiently analyzing confocal fluorescence image data of giant unilamellar vesicles. The program can automatically identify GUVs with desired morphology and perform intensity-based calculation and state decision for each vesicle. We expect our method of CNN implementation can be expanded and applied to many similar problems in image data analysis.


Assuntos
Inteligência Artificial , Lipossomas Unilamelares , Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Reprodutibilidade dos Testes
5.
Stroke ; 53(12): 3622-3632, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36128905

RESUMO

BACKGROUND: A high and low estimated glomerular filtration rate (eGFR) could affect outcomes after reperfusion therapy for ischemic stroke. This study aimed to determine whether renal function based on eGFR affects mortality risk in patients with ischemic stroke within 6 months following reperfusion therapy. METHODS: This prospective registry-based cohort study included 2266 patients who received reperfusion therapy between January 2000 and September 2019 and were registered in the SECRET (Selection Criteria in Endovascular Thrombectomy and Thrombolytic Therapy) study or the Yonsei Stroke Cohort. A high and low eGFR were based on the Chronic Kidney Disease Epidemiology Collaboration equation and defined, respectively, as the 5th and 95th percentiles of age- and sex-specific eGFR. Occurrence of death within 6 months was compared among the groups according to their eGFR such as low, normal, or high eGFR. RESULTS: Of the 2266 patients, 2051 (90.5%) had a normal eGFR, 110 (4.9%) a low eGFR, and 105 (4.6%) a high eGFR. Patients with high eGFR were younger or less likely to have hypertension, diabetes, or atrial fibrillation than the other groups. Active cancer was more prevalent in the high-eGFR group. During the 6-month follow-up, there were 24 deaths (22.9%) in the high-eGFR group, 37 (33.6%) in the low-eGFR group, and 237 (11.6%) in the normal-eGFR group. After adjusting for variables with P<0.10 in the univariable analysis, 6-month mortality was independently associated with high eGFR (hazard ratio, 2.22 [95% CI, 1.36-3.62]; P=0.001) and low eGFR (HR, 2.29 [95% CI, 1.41-3.72]; P=0.001). These associations persisted regardless of treatment modality or various baseline characteristics. CONCLUSIONS: High eGFR as well as low eGFR were independently associated with 6-month mortality after reperfusion therapy. Kidney function could be considered a prognostic factor in patients with ischemic stroke after reperfusion therapy.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Masculino , Feminino , Humanos , Estudos de Coortes , Rim/fisiologia , Taxa de Filtração Glomerular , Acidente Vascular Cerebral/epidemiologia , Reperfusão , Fatores de Risco
6.
Langmuir ; 38(15): 4702-4712, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35385290

RESUMO

Protein cargos anchored on the lipid membrane can be segregated by fluidic domain phase separation. Lipid membranes at certain compositions may separate into lipid domains to segregate cargos, and protein cargos themselves may be involved in protein condensate domain formation with multivalent binding proteins to segregate cargos. Recent studies suggest that these two driving forces of phase separation closely interact on the lipid membranes to promote codomain formation. In this report, we studied the effect of cargo density on the outcome of the cargo phase separation on giant unilamellar vesicles. Proteins and lipids are connected only by the anchored cargos, so it was originally hypothesized that higher cargo density would increase the degree of interaction between the lipid and protein domains, promoting more phase separation. However, fluorescence image analysis on different cargo densities showed that the cooperative domain formation and steric pressure are at a tug of war opposing each other. Cooperative domain formation is dominant under lower anchor density conditions, and above a threshold density, steric pressure was dominant opposing the domain formation. The result suggests that the cargo density is a key parameter affecting the outcome of cargo organization on the lipid membranes by phase separation.


Assuntos
Microdomínios da Membrana , Lipossomas Unilamelares , Fenômenos Biofísicos , Bicamadas Lipídicas/química , Lipídeos/química , Microdomínios da Membrana/química , Proteínas/metabolismo , Lipossomas Unilamelares/química
7.
Proc Natl Acad Sci U S A ; 112(52): 15892-7, 2015 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-26668364

RESUMO

The endosomal sorting complexes required for transport (ESCRT) machinery functions in HIV-1 budding, cytokinesis, multivesicular body biogenesis, and other pathways, in the course of which it interacts with concave membrane necks and bud rims. To test the role of membrane shape in regulating ESCRT assembly, we nanofabricated templates for invaginated supported lipid bilayers. The assembly of the core ESCRT-III subunit CHMP4B/Snf7 is preferentially nucleated in the resulting 100-nm-deep membrane concavities. ESCRT-II and CHMP6 accelerate CHMP4B assembly by increasing the concentration of nucleation seeds. Superresolution imaging was used to visualize CHMP4B/Snf7 concentration in a negatively curved annulus at the rim of the invagination. Although Snf7 assemblies nucleate slowly on flat membranes, outward growth onto the flat membrane is efficiently nucleated at invaginations. The nucleation behavior provides a biophysical explanation for the timing of ESCRT-III recruitment and membrane scission in HIV-1 budding.


Assuntos
Membrana Celular/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Endossomos/metabolismo , Bicamadas Lipídicas/metabolismo , Algoritmos , Membrana Celular/virologia , Recuperação de Fluorescência Após Fotodegradação , HIV/fisiologia , Humanos , Microscopia de Força Atômica , Microscopia de Fluorescência/métodos , Modelos Biológicos , Transporte Proteico , Replicação Viral
8.
Neurointervention ; 19(1): 52-56, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38303611

RESUMO

A rupture of a femoral pseudoaneurysm is an extremely rare complication of endovascular procedures, but its outcome can be life-threatening. In this report, we present a case of a femoral pseudoaneursym rupture in a patient in their early 90s following intra-arterial mechanical thrombectomy for acute ischemic stroke. Despite receiving medical and surgical interventions, the patient subsequently developed multiple organ failure, ultimately resulting in death. This case emphasizes the critical role of appropriate selection of vascular closure technique and careful post-procedural monitoring, particularly in high-risk patients.

9.
Biochim Biophys Acta Biomembr ; 1866(2): 184256, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37989398

RESUMO

Vesicular trafficking facilitates material transport between membrane-bound organelles. Membrane protein cargos are trafficked for relocation, recycling, and degradation during various physiological processes. In vitro fusion studies utilized synthetic lipid membranes to study the molecular mechanisms of vesicular trafficking and to develop synthetic materials mimicking the biological membrane trafficking. Various fusogenic conditions which can induce vesicular fusion have been used to establish synthetic systems that can mimic biological systems. Despite these efforts, the mechanisms underlying vesicular trafficking of membrane proteins remain limited and robust in vitro methods that can construct synthetic trafficking systems for membrane proteins between large membranes (>1 µm2) are unavailable. Here, we provide data to show the spontaneous transfer of small membrane-bound peptides (∼4 kD) between a supported lipid bilayer (SLB) and giant unilamellar vesicles (GUVs). We found that the contact between the SLB and GUVs led to the occasional but notable transfer of membrane-bound peptides in a physiological saline buffer condition (pH 7.4, 150 mM NaCl). Quantitative and dynamic time-lapse analyses suggested that the observed exchange occurred through the formation of hemi-fusion stalks between the SLB and GUVs. Larger protein cargos with a size of ∼77 kD could not be transferred between the SLB and GUVs, suggesting that the larger-sized cargos limited diffusion across the hemi-fusion stalk, which was predicted to have a highly curved structure. Compositional study showed Ni-chelated lipid head group was the essential component catalyzing the process. Our system serves as an example synthetic platform that enables the investigation of small-peptide trafficking between synthetic membranes and reveals hemi-fused lipid bridge formation as a mechanism of peptide transfer.


Assuntos
Bicamadas Lipídicas , Lipossomas Unilamelares , Lipossomas Unilamelares/química , Bicamadas Lipídicas/química , Peptídeos , Proteínas de Membrana
10.
Sci Rep ; 14(1): 304, 2024 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172278

RESUMO

This study aimed to investigate whether there was a difference in one-year outcome after stroke between patients treated with antiplatelet and anticoagulation (OAC + antiplatelet) and those with anticoagulation only (OAC), when comorbid atherosclerotic disease was present with non-valvular atrial fibrillation (NVAF). This was a retrospective study using a prospective cohort of consecutive patients with ischemic stroke. Patients with NVAF and comorbid atherosclerotic disease were assigned to the OAC + antiplatelet or OAC group based on discharge medication. All-cause mortality, recurrent ischemic stroke, hemorrhagic stroke, myocardial infarction, and bleeding events within 1 year after the index stroke were compared. Of the 445 patients included in this study, 149 (33.5%) were treated with OAC + antiplatelet. There were no significant differences in all outcomes between groups. After inverse probability of treatment weighting, OAC + antiplatelet was associated with a lower risk of all-cause mortality (hazard ratio 0.48; 95% confidence interval 0.23-0.98; P = 0.045) and myocardial infarction (0% vs. 3.0%, P < 0.001). The risk of hemorrhagic stroke was not significantly different (P = 0.123). OAC + antiplatelet was associated with a decreased risk of all-cause mortality and myocardial infarction but an increased risk of ischemic stroke among patients with NVAF and systemic atherosclerotic diseases.


Assuntos
Aterosclerose , Fibrilação Atrial , AVC Isquêmico , Infarto do Miocárdio , Acidente Vascular Cerebral , Humanos , Anticoagulantes/efeitos adversos , Fibrilação Atrial/complicações , Fibrilação Atrial/tratamento farmacológico , Estudos Retrospectivos , Estudos Prospectivos , Acidente Vascular Cerebral/complicações , Infarto do Miocárdio/tratamento farmacológico , Aterosclerose/complicações , Aterosclerose/tratamento farmacológico , Aterosclerose/induzido quimicamente , AVC Isquêmico/tratamento farmacológico , Administração Oral , Inibidores da Agregação Plaquetária/efeitos adversos
11.
Sci Rep ; 14(1): 12656, 2024 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-38825610

RESUMO

This study aimed to investigate the relationship between complex aortic plaque (CAP) and short-term as well as long-term outcomes following cardioembolic stroke. CAP is a known risk factor for occurrence and recurrence of ischemic stroke. However, the association of CAP on cardioembolic stroke remains unclear. This was retrospective study using prospective cohort of consecutive patients with cardioembolic stroke who underwent transesophageal echocardiography. The functional outcome was evaluated using the modified Rankin Scale score at 3 months, and long-term outcomes were assessed by recurrence of ischemic stroke and occurrence of major adverse cardiovascular events (MACE). Among 759 patients with cardioembolic stroke, 91 (12.0%) had CAP. Early ischemic stroke recurrence within 3 months was associated with CAP (p = 0.025), whereas CAP was not associated with functional outcome at 3 months (odd ratio 1.01, 95% confidence interval [CI] 0.57-1.84, p = 0.973). During a median follow-up of 3.02 years, CAP was significantly associated with ischemic stroke recurrence (hazard ratio = 2.68, 95% CI 1.48-4.88, p = 0.001) and MACE occurrence (hazard ratio = 1.61, 95% CI 1.03-2.51, p = 0.039). In conclusion, CAP was associated with early ischemic stroke recurrence and poor long-term outcomes in patients with cardioembolic stroke. It might be helpful to consider transesophageal echocardiography for patients with cardioembolic stroke to identify CAP.


Assuntos
AVC Embólico , AVC Isquêmico , Placa Aterosclerótica , Humanos , Masculino , Feminino , Idoso , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/etiologia , AVC Isquêmico/complicações , Placa Aterosclerótica/complicações , Placa Aterosclerótica/diagnóstico por imagem , Prognóstico , Pessoa de Meia-Idade , Estudos Retrospectivos , AVC Embólico/etiologia , Ecocardiografia Transesofagiana , Fatores de Risco , Recidiva , Doenças da Aorta/complicações , Doenças da Aorta/diagnóstico por imagem , Estudos Prospectivos , Idoso de 80 Anos ou mais
12.
Sci Rep ; 14(1): 9295, 2024 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-38653743

RESUMO

The prognosis of patients with embolic stroke of undetermined source (ESUS) may vary according to the underlying cause. Therefore, we aimed to divide ESUS into subtypes and assess the long-term outcomes. Consecutive patients with acute ischemic stroke who underwent a comprehensive workup, including transesophageal echocardiography and prolonged electrocardiography monitoring, were enrolled. We classified ESUS into minor cardioembolic (CE) ESUS, arteriogenic ESUS, two or more causes ESUS, and no cause ESUS. Arteriogenic ESUS was sub-classified into complex aortic plaque (CAP) ESUS and non-stenotic (< 50%) relevant artery plaque (NAP) ESUS. A total of 775 patients were enrolled. During 1286 ± 748 days follow-up, 116 major adverse cardiovascular events (MACE) occurred (4.2 events/100 patient-years). Among the ESUS subtypes, CAP ESUS was associated with the highest MACE frequency (9.7/100 patient-years, p = 0.021). Cox regression analyses showed that CAP ESUS was associated with MACE (hazard ratio 2.466, 95% confidence interval 1.305-4.660) and any stroke recurrence (hazard ratio 2.470, 95% confidence interval, 1.108-5.508). The prognosis of ESUS varies according to the subtype, with CAP ESUS having the worst prognosis. Categorizing ESUS into subtypes could improve patient care and refine clinical trials.


Assuntos
AVC Embólico , Humanos , Masculino , Feminino , AVC Embólico/etiologia , Idoso , Pessoa de Meia-Idade , Prognóstico , Ecocardiografia Transesofagiana , Fatores de Risco , AVC Isquêmico/etiologia , Placa Aterosclerótica/complicações , Placa Aterosclerótica/diagnóstico por imagem , Seguimentos
13.
Int J Stroke ; : 17474930241265652, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38907672

RESUMO

BACKGROUND: Multiple attempts of thrombectomy have been linked to a higher risk of intracerebral hemorrhage and worsened functional outcomes, potentially influenced by blood pressure (BP) management strategies. Nonetheless, the impact of intensive BP management following successful recanalization through multiple attempts remains uncertain. AIMS: This study aimed to investigate whether conventional and intensive BP management differentially affect outcomes according to multiple-attempt recanalization (MAR) and first-attempt recanalization (FAR) groups. METHODS: In this secondary analysis of the OPTIMAL-BP trial, which was a comparison of intensive (systolic BP target <140 mm Hg) and conventional (systolic BP target 140-180 mm Hg) BP managements during the 24 hours after successful recanalization, we included intention-to-treat population of the trial. Patients were divided into the MAR and the FAR groups. We examined a potential interaction between the number of thrombectomy attempts (MAR and FAR groups) and the effect of BP managements on clinical and safety outcomes. The primary outcome was functional independence at 3 months. Safety outcomes were symptomatic intracerebral hemorrhage within 36 hours and mortality within 3 months. RESULTS: Of the 305 patients (median 75 years), 102 (33.4%) were in the MAR group and 203 (66.6%) were in the FAR group. The intensive BP management was significantly associated with a lower rate of functional independence in the MAR group (intensive, 32.7% vs. conventional, 54.9%, adjusted OR 0.33, 95% CI 0.12-0.90, p = 0.03). In the FAR group, the proportion of patients with functional independence was not significantly different between the BP managements (intensive, 42.5% vs. conventional, 54.2%, adjusted OR 0.73, 95% CI 0.38-1.40). Incidences of symptomatic intracerebral hemorrhage and mortality rates were not significantly different according to the BP managements in both MAR and FAR groups. CONCLUSIONS: Among stroke patients who received multiple attempts of thrombectomy, intensive BP management for 24 hours resulted in a reduced chance of functional independence at 3 months and did not reduce symptomatic intracerebral hemorrhage following successful reperfusion.

14.
JAMA Netw Open ; 7(4): e246878, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38630474

RESUMO

Importance: The associations between blood pressure (BP) decreases induced by medication and functional outcomes in patients with successful endovascular thrombectomy remain uncertain. Objective: To evaluate whether BP reductions induced by intravenous BP medications are associated with poor functional outcomes at 3 months. Design, Setting, and Participants: This cohort study was a post hoc analysis of the Outcome in Patients Treated With Intra-Arterial Thrombectomy-Optimal Blood Pressure Control trial, a comparison of intensive and conventional BP management during the 24 hours after successful recanalization from June 18, 2020, to November 28, 2022. This study included 302 patients who underwent endovascular thrombectomy, achieved successful recanalization, and exhibited elevated BP within 2 hours of successful recanalization at 19 stroke centers in South Korea. Exposure: A BP decrease was defined as at least 1 event of systolic BP less than 100 mm Hg. Patients were divided into medication-induced BP decrease (MIBD), spontaneous BP decrease (SpBD), and no BP decrease (NoBD) groups. Main Outcomes and Measures: The primary outcome was a modified Rankin scale score of 0 to 2 at 3 months, indicating functional independence. Primary safety outcomes were symptomatic intracerebral hemorrhage within 36 hours and mortality due to index stroke within 3 months. Results: Of the 302 patients (median [IQR] age, 75 [66-82] years; 180 [59.6%] men), 47 (15.6%)were in the MIBD group, 39 (12.9%) were in the SpBD group, and 216 (71.5%) were in the NoBD group. After adjustment for confounders, the MIBD group exhibited a significantly smaller proportion of patients with functional independence at 3 months compared with the NoBD group (adjusted odds ratio [AOR], 0.45; 95% CI, 0.20-0.98). There was no significant difference in functional independence between the SpBD and NoBD groups (AOR, 1.41; 95% CI, 0.58-3.49). Compared with the NoBD group, the MIBD group demonstrated higher odds of mortality within 3 months (AOR, 5.15; 95% CI, 1.42-19.4). The incidence of symptomatic intracerebral hemorrhage was not significantly different among the groups (MIBD vs NoBD: AOR, 1.89; 95% CI, 0.54-5.88; SpBD vs NoBD: AOR, 2.75; 95% CI, 0.76-9.46). Conclusions and Relevance: In this cohort study of patients with successful endovascular thrombectomy after stroke, MIBD within 24 hours after successful recanalization was associated with poor outcomes at 3 months. These findings suggested lowering systolic BP to below 100 mm Hg using BP medication might be harmful.


Assuntos
Hipertensão , Acidente Vascular Cerebral , Idoso , Feminino , Humanos , Masculino , Pressão Sanguínea , Hemorragia Cerebral , Estudos de Coortes , Hipertensão/epidemiologia , Pressão , Acidente Vascular Cerebral/cirurgia , Idoso de 80 Anos ou mais
15.
J Stroke ; 25(1): 111-118, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36592972

RESUMO

BACKGROUND AND PURPOSE: Left atrial or left atrial appendage (LA/LAA) thrombi are frequently observed during cardioembolic evaluation in patients with ischemic stroke. This study aimed to investigate stroke outcomes in patients with LA/LAA thrombus. METHODS: This retrospective study included patients admitted to a single tertiary center in Korea between January 2012 and December 2020. Patients with nonvalvular atrial fibrillation who underwent transesophageal echocardiography or multi-detector coronary computed tomography were included in the study. Poor outcome was defined as modified Rankin Scale score >3 at 90 days. The inverse probability of treatment weighting analysis was performed. RESULTS: Of the 631 patients included in this study, 68 (10.7%) had LA/LAA thrombi. Patients were likely to have a poor outcome when an LA/LAA thrombus was detected (42.6% vs. 17.4%, P<0.001). Inverse probability of treatment weighting analysis yielded a higher probability of poor outcomes in patients with LA/LAA thrombus than in those without LA/LAA thrombus (P<0.001). Patients with LA/LAA thrombus were more likely to have relevant arterial occlusion on angiography (36.3% vs. 22.4%, P=0.047) and a longer hospital stay (8 vs. 7 days, P<0.001) than those without LA/LAA thrombus. However, there was no difference in early neurological deterioration during hospitalization or major adverse cardiovascular events within 3 months between the two groups. CONCLUSIONS: Patients with ischemic stroke who had an LA/LAA thrombus were at risk of a worse functional outcome after 3 months, which was associated with relevant arterial occlusion and prolonged hospital stay.

16.
Neurointervention ; 18(3): 204-208, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37723651

RESUMO

We present a case of delayed migration of an open-cell design carotid stent, which is a rare complication following carotid artery stenting (CAS). A 65-year-old patient with carotid artery stenosis underwent CAS with an open-cell stent, initially achieving successful deployment. However, 4 months later, the stent migrated and resulted in restenosis. The patient underwent balloon angioplasty and received an additional stent, leading to improved blood flow. The rarity of stent migration, particularly in the absence of risk factors, highlights the need for clinicians to be vigilant and consider early imaging follow-up for patients at risk of this complication after CAS.

17.
Sci Rep ; 13(1): 14568, 2023 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-37666907

RESUMO

Clot perviousness on computerized tomography (CT) is predictive of response to reperfusion therapy. This study aimed to determine the association of clot perviousness with ultrastructural features of clot in stroke patients undergoing endovascular thrombectomy. We quantitatively analyzed the ultrastructural components identified using scanning electron microscopy. The clot components were determined in the inner portions of the clots. Clot perviousness was assessed as thrombus attenuation increase (TAI) using noncontrast CT and CT angiography. We compared the association between the identified ultrastructural components and clot perviousness. The proportion of pores consisted of 3.5% on scanning electron microscopy images. The proportion of porosity in the inner portion was 2.5%. Among the ultrastructural components, polyhedrocytes were most commonly observed. The mean TAI was 9.3 ± 10.0 (median 5.6, interquartile range 1.1-14.3) Hounsfield units. TAI correlated positively with inner porosity (r = 0.422, p = 0.020). Among the ultrastructural clot components, TAI was independently associated with polyhedrocytes (B = - 0.134, SE = 0.051, p = 0.008). Clot perviousness is associated with porosity and the proportion of polyhdrocytes of clots.


Assuntos
Acidente Vascular Cerebral , Trombose , Humanos , Clotrimazol , Angiografia por Tomografia Computadorizada , Acidente Vascular Cerebral/diagnóstico por imagem , Trombectomia , Trombose/diagnóstico por imagem
18.
Sci Rep ; 13(1): 9550, 2023 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-37308509

RESUMO

We investigated the prognostic impact of central blood pressure (BP) on outcomes in patients with embolic stroke of undetermined source (ESUS). The prognostic value of central BP according to ESUS subtype was also evaluated. We recruited patients with ESUS and data on their central BP parameters (central systolic BP [SBP], central diastolic BP [DBP], central pulse pressure [PP], augmentation pressure [AP], and augmentation index [AIx]) during admission. ESUS subtype classification was arteriogenic embolism, minor cardioembolism, two or more causes, and no cause. Major adverse cardiovascular event (MACE) was defined as recurrent stroke, acute coronary syndrome, hospitalization for heart failure, or death. Over a median of 45.8 months, 746 patients with ESUS were enrolled and followed up. Patients had a mean age of 62.8 years, and 62.2% were male. Multivariable Cox regression analysis showed that central SBP and PP were associated with MACE. All-cause mortality was independently associated with AIx. In patients with no cause ESUS, central SBP and PP, AP, and AIx were independently associated with MACE. AP and AIx were independently associated with all-cause mortality (all p < 0.05). We demonstrated that central BP can predict poor long-term prognosis in patients with ESUS, especially those with the no cause ESUS subtype.


Assuntos
Síndrome Coronariana Aguda , AVC Embólico , Insuficiência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Pressão Sanguínea , Prognóstico
19.
Front Neurol ; 13: 979073, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36203995

RESUMO

Background: Understanding the factors related to early neurologic deterioration (END) is crucial in the management of patients with lacunar infarction. Blood viscosity is a significant factor for microvascular perfusion. We investigated the association between blood viscosity and occurrence of END in lacunar infarction. Methods: We included consecutive patients admitted for lacunar infarction within 72 h from symptoms onset. END was defined as an increase in the National Institute of Health Stroke Scale (NIHSS) score ≥2 within 24 h of admission. Viscosity was measured within 24 h of hospitalization with a scanning capillary tube viscometer. Viscosity measured at a shear rate of 300 s-1 was defined as systolic blood viscosity (SBV), whereas that measured at a shear rate of 5 s-1 as diastolic blood viscosity (DBV). Results: Of the 178 patients included (median age, 65.5; interquartile range [IQR], 56.0, 76.0], END occurred in 33 (18.5%). DBV was significantly higher in patients with END than those without END (13.3 mPa·s [IQR 11.8, 16.0] vs. 12.3 mPa·s [IQR11.0, 13.5]; P = 0.023). In the multivariate analysis, DBV was independently associated with the occurrence of END (odds ratio 1.17; 95% confidence interval 1.01-1.36; P = 0.043). Subgroup analysis showed no heterogeneity in the effect of viscosity on the occurrence of END. Conclusions: Blood viscosity at a low shear rate (DBV) was associated with the occurrence of END in patients with lacunar infarction. Blood rheology may be important in pathophysiology of END in patients with lacunar infarction.

20.
J Clin Med ; 11(11)2022 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-35683461

RESUMO

We investigated the association of low ankle-brachial index (ABI < 0.9) with major adverse cardiovascular events (MACE) and all-cause mortality in patients with embolic stroke of undetermined source (ESUS) as well as whether the association differed by ESUS subtype. This retrospective single-center study included ESUS patients who underwent transesophageal echocardiography and ABI during hospitalization. ESUS was classified as ESUS with minor cardioembolic source, arteriogenic embolism, two or more causes, or no cause. Arteriogenic embolism was defined and classified as complex aortic or non-stenotic relevant artery plaque. MACE was defined as stroke recurrence, acute coronary syndrome, hospitalization for heart failure, or death. Overall, 829 patients were included, with a median follow-up of 45.8 months. Of these, 42 (5.1%) and 370 (44.6%) had low ABI and arteriogenic embolism, respectively. ABI < 0.9 was independently associated with MACE (hazard ratio [HR]: 2.038, 95% confidence interval [CI]: 1.093−3.801) and all-cause mortality (HR: 3.608, 95% CI: 1.538−8.465) according to the multivariable Cox regression analysis. Between ESUS subtypes, low ABI was independently associated with MACE (HR: 2.513, 95% CI: 1.257−5.023) and all-cause mortality (HR: 5.681, 95% CI: 2.151−15.008) in arteriogenic embolism patients, especially in those with complex aortic plaque. However, in non-arteriogenic embolism patients, low ABI was not related to MACE and mortality. In ESUS patients, low ABI was linked to MACE and all-cause mortality, especially in those with arteriogenic embolisms from complex aortic plaque.

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