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1.
Cell ; 165(2): 434-448, 2016 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-26997484

RESUMEN

Mutations in the Kv3.3 potassium channel (KCNC3) cause cerebellar neurodegeneration and impair auditory processing. The cytoplasmic C terminus of Kv3.3 contains a proline-rich domain conserved in proteins that activate actin nucleation through Arp2/3. We found that Kv3.3 recruits Arp2/3 to the plasma membrane, resulting in formation of a relatively stable cortical actin filament network resistant to cytochalasin D that inhibits fast barbed end actin assembly. These Kv3.3-associated actin structures are required to prevent very rapid N-type channel inactivation during short depolarizations of the plasma membrane. The effects of Kv3.3 on the actin cytoskeleton are mediated by the binding of the cytoplasmic C terminus of Kv3.3 to Hax-1, an anti-apoptotic protein that regulates actin nucleation through Arp2/3. A human Kv3.3 mutation within a conserved proline-rich domain produces channels that bind Hax-1 but are impaired in recruiting Arp2/3 to the plasma membrane, resulting in growth cones with deficient actin veils in stem cell-derived neurons.


Asunto(s)
Citoesqueleto de Actina/metabolismo , Proteína 2 Relacionada con la Actina/metabolismo , Proteína 3 Relacionada con la Actina/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Canales de Potasio Shaw/metabolismo , Ataxias Espinocerebelosas/metabolismo , Complejo 2-3 Proteico Relacionado con la Actina/metabolismo , Secuencia de Aminoácidos , Membrana Celular/metabolismo , Datos de Secuencia Molecular , Mutación , Neuronas/metabolismo , Células Madre Pluripotentes/metabolismo , Canales de Potasio Shaw/química , Canales de Potasio Shaw/genética , Transducción de Señal , Proteínas de Unión al GTP rac/metabolismo
2.
Stroke ; 54(11): 2842-2850, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37795589

RESUMEN

BACKGROUND: Right to left shunt (RLS), including patent foramen ovale, is a recognized risk factor for stroke. RLS/patent foramen ovale diagnosis is made by transthoracic echocardiography (TTE), which is insensitive, transesophageal echocardiography, which is invasive, and transcranial Doppler (TCD), which is noninvasive and accurate but scarce. METHODS: We conducted a prospective, single-arm device clinical trial of robot-assisted TCD (raTCD) versus TTE for RLS diagnosis at 6 clinical sites in patients who presented with an event suspicious for embolic cerebrovascular ischemia from October 6, 2020 to October 20, 2021. raTCD was performed with standard TCD bubble study technique. TTE bubble study was performed per local standards. The primary outcome was rate of RLS detection by raTCD versus TTE. RESULTS: A total of 154 patients were enrolled, 129 evaluable (intent to scan) and 121 subjects had complete data per protocol. In the intent to scan cohort, mean age was 60±15 years, 47% were women, and all qualifying events were diagnosed as ischemic stroke or transient ischemic attack. raTCD was positive for RLS in 82 subjects (64%) and TTE was positive in 26 (20%; absolute difference 43.4% [95% CI, 35.2%-52.0%]; P<0.001). On prespecified secondary analysis, large RLS was detected by raTCD in 35 subjects (27%) versus 13 (10%) by TTE (absolute difference 17.0% [95% CI, 11.5%-24.5%]; P<0.001). There were no serious adverse events. CONCLUSIONS: raTCD was safe and ≈3 times more likely to diagnose RLS than TTE. TTE completely missed or underdiagnosed two thirds of large shunts diagnosed by raTCD. The raTCD device, used by health professionals with no prior TCD training, may allow providers to achieve the known sensitivity of TCD for RLS and patent foramen ovale detection without the need for an experienced operator to perform the test. Pending confirmatory studies, TCD appears to be the superior screen for RLS compared with TTE (funded by NeuraSignal). REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT04604015.


Asunto(s)
Foramen Oval Permeable , Robótica , Accidente Cerebrovascular , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ecocardiografía , Ecocardiografía Transesofágica , Foramen Oval Permeable/complicaciones , Estudios Prospectivos , Accidente Cerebrovascular/etiología , Ultrasonografía Doppler Transcraneal
3.
Stroke ; 50(1): 143-147, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30580705

RESUMEN

Background and Purpose- Although aggressive medical therapy was superior to stenting in the SAMMPRIS trial (Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis), the stroke rate in the medical arm was still high. The aim of this study was to determine the association between hemodynamic markers (borderzone infarct pattern and impaired collateral flow on baseline imaging) and rates of recurrent stroke in patients treated medically in SAMMPRIS. Methods- This was a post hoc analysis of patients whose qualifying event for SAMMPRIS was an infarct in the territory of a stenotic middle cerebral artery or intracranial carotid artery. Infarcts were adjudicated as involving primarily internal or cortical borderzone territories, the core middle cerebral artery territory, or perforator territories, and collateral flow was assessed according to a standard scale (American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology). Log-rank tests and χ2 tests were performed to assess associations of infarct patterns and collateral flow with rates of recurrent stroke. Results- Of 101 patients who qualified, 14 of 53 (26.4%) with borderzone infarcts, 2 of 24 (8.3%) with core middle cerebral artery infarcts, and 3 of 24 (12.5%) with perforator infarcts had a recurrent stroke in the territory (P=0.14 for comparing the 3 groups, P=0.052 for borderzone versus nonborderzone). Of 82 patients with collateral flow assessment, 30 of 43 (70%) with borderzone infarcts, 7 of 19 (37%) with core middle cerebral artery infarcts, and 11 of 20 (55%) with perforator infarcts had impaired collateral flow distal to the stenosis (P=0.049). Patients with borderzone infarcts and impaired collateral flow had the highest risk of recurrent stroke (37%). Conclusions- Borderzone infarcts and impaired collateral flow identify a subgroup of patients with intracranial stenosis who are at particularly high risk of recurrent stroke on medical treatment. Clinical Trial Registration- URL: https://www.clinicaltrials.gov. Unique identifier: NCT00576693.

4.
Ann Neurol ; 84(5): 717-728, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30295338

RESUMEN

OBJECTIVE: The present study was undertaken to determine the efficacy of coadministration of fingolimod with alteplase in acute ischemic stroke patients in a delayed time window. METHODS: This was a prospective, randomized, open-label, blinded endpoint clinical trial, enrolling patients with internal carotid artery or middle cerebral artery proximal occlusion within 4.5 to 6 hours from symptom onset. Patients were randomly assigned to receive alteplase alone or alteplase with fingolimod. All patients underwent pretreatment and 24-hour noncontrast computed tomography (CT)/perfusion CT/CT angiography. The coprimary endpoints were the decrease of National Institutes of Health Stroke Scale scores over 24 hours and the favorable shift of modified Rankin Scale score (mRS) distribution at day 90. Exploratory outcomes included vessel recanalization, anterograde reperfusion, and retrograde reperfusion of collateral flow. RESULTS: Each treatment group included 23 patients. Compared with alteplase alone, patients receiving fingolimod plus alteplase exhibited better early clinical improvement at 24 hours and a favorable shift of mRS distribution at day 90. In addition, patients who received fingolimod and alteplase exhibited a greater reduction in the perfusion lesion accompanied by suppressed infarct growth by 24 hours. Fingolimod in conjunction with alteplase significantly improved anterograde reperfusion of downstream territory and prevented the failure of retrograde reperfusion from collateral circulation. INTERPRETATION: Fingolimod may enhance the efficacy of alteplase administration in the 4.5- to 6-hour time window in patients with a proximal cerebral arterial occlusion and salvageable penumbral tissue by promoting both anterograde reperfusion and retrograde collateral flow. These findings are instructive for the design of future trials of recanalization therapies in extended time windows. Ann Neurol 2018;84:725-736.


Asunto(s)
Fibrinolíticos/administración & dosificación , Clorhidrato de Fingolimod/administración & dosificación , Inmunosupresores/administración & dosificación , Accidente Cerebrovascular/tratamiento farmacológico , Activador de Tejido Plasminógeno/administración & dosificación , Anciano , Circulación Colateral/efectos de los fármacos , Quimioterapia Combinada , Femenino , Humanos , Masculino , Recuperación de la Función/efectos de los fármacos , Reperfusión , Accidente Cerebrovascular/patología , Tiempo de Tratamiento
5.
Curr Opin Neurol ; 36(2): 124, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-36862013
6.
Clin Sci (Lond) ; 132(5): 581-593, 2018 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-29500223

RESUMEN

Significant neuroprotective effects of angiotensin II type 2 (AT2) receptor (AT2 receptor) agonists in ischemic stroke have been previously demonstrated in multiple studies. However, the routes of agonist application used in these pre-clinical studies, direct intracerebroventricular (ICV) and systemic administration, are unsuitable for translation into humans; in the latter case because AT2 receptor agonists are blood-brain barrier (BBB) impermeable. To circumvent this problem, in the current study we utilized the nose-to-brain (N2B) route of administration to bypass the BBB and deliver the selective AT2 receptor agonist Compound 21 (C21) to naïve rats or rats that had undergone endothelin 1 (ET-1)-induced ischemic stroke. The results obtained from the present study indicated that C21 applied N2B entered the cerebral cortex and striatum within 30 min in amounts that are therapeutically relevant (8.4-9 nM), regardless of whether BBB was intact or disintegrated. C21 was first applied N2B at 1.5 h after stroke indeed provided neuroprotection, as evidenced by a highly significant, 57% reduction in cerebral infarct size and significant improvements in Bederson and Garcia neurological scores. N2B-administered C21 did not affect blood pressure or heart rate. Thus, these data provide proof-of-principle for the idea that N2B application of an AT2 receptor agonist can exert neuroprotective actions when administered following ischemic stroke. Since N2B delivery of other agents has been shown to be effective in certain human central nervous system diseases, the N2B application of AT2 receptor agonists may become a viable mode of delivering these neuroprotective agents for human ischemic stroke patients.


Asunto(s)
Encéfalo/metabolismo , Mucosa Nasal/metabolismo , Receptor de Angiotensina Tipo 2/agonistas , Accidente Cerebrovascular/prevención & control , Sulfonamidas/farmacología , Tiofenos/farmacología , Animales , Isquemia Encefálica/complicaciones , Infarto Cerebral/prevención & control , Vías de Administración de Medicamentos , Sistemas de Liberación de Medicamentos/métodos , Humanos , Masculino , Fármacos Neuroprotectores/administración & dosificación , Fármacos Neuroprotectores/sangre , Fármacos Neuroprotectores/farmacología , Ratas Sprague-Dawley , Receptor de Angiotensina Tipo 2/metabolismo , Accidente Cerebrovascular/etiología , Sulfonamidas/administración & dosificación , Sulfonamidas/sangre , Tiofenos/administración & dosificación , Tiofenos/sangre
7.
Cerebellum ; 17(5): 692-697, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29949095

RESUMEN

Mutations in the potassium channel gene KCNC3 (Kv3.3) cause the autosomal dominant neurological disease, spinocerebellar ataxia 13 (SCA13). In this study, we expand the genotype-phenotype repertoire of SCA13 by describing the novel KCNC3 deletion p.Pro583_Pro585del highlighting the allelic heterogeneity observed in SCA13 patients. We characterize adult-onset, progressive clinical symptoms of two afflicted kindred and introduce the symptom of profound spasticity not previously associated with the SCA13 phenotype. We also present molecular and electrophysiological characterizations of the mutant protein in mammalian cell culture. Mechanistically, the p.Pro583_Pro585del protein showed normal membrane trafficking with an altered electrophysiological profile, including slower inactivation and decreased sensitivity to the inactivation-accelerating effects of the actin depolymerizer latrunculin B. Taken together, our results highlight the clinical importance of the intracellular C-terminal portion of Kv3.3 and its association with ion channel function.


Asunto(s)
Espasticidad Muscular/genética , Espasticidad Muscular/fisiopatología , Eliminación de Secuencia , Canales de Potasio Shaw/genética , Ataxias Espinocerebelosas/congénito , Adulto , Animales , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Células CHO , Cricetulus , Femenino , Humanos , Masculino , Toxinas Marinas/farmacología , Potenciales de la Membrana/efectos de los fármacos , Potenciales de la Membrana/fisiología , Espasticidad Muscular/diagnóstico por imagen , Fenotipo , Ataxias Espinocerebelosas/diagnóstico por imagen , Ataxias Espinocerebelosas/genética , Ataxias Espinocerebelosas/fisiopatología , Tiazolidinas/farmacología
8.
Proc Natl Acad Sci U S A ; 112(4): 1155-60, 2015 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-25583472

RESUMEN

Cerebral vasospasm (CV) and the resulting delayed cerebral ischemia (DCI) significantly contribute to poor outcomes following aneurysmal subarachnoid hemorrhage (aSAH). Free hemoglobin (Hb) within the subarachnoid space has been implicated in the pathogenesis of CV. Haptoglobin (Hp) binds free pro-oxidant Hb, thereby modulating its harmful effects. Humans can be of three Hp phenotypes: Hp1-1, Hp2-1, or Hp2-2. In several disease states, the Hp2-2 protein has been associated with reduced ability to protect against toxic free Hb. We hypothesized that individuals with the Hp2-2 phenotype would have more CV, DCI, mortality, and worse functional outcomes after aSAH. In a sample of 74 aSAH patients, Hp2-2 phenotype was significantly associated with increased focal moderate (P = 0.014) and severe (P = 0.008) CV and more global CV (P = 0.014) after controlling for covariates. Strong trends toward increased mortality (P = 0.079) and worse functional outcomes were seen for the Hp2-2 patients with modified Rankin scale at 6 wk (P = 0.076) and at 1 y (P = 0.051) and with Glasgow Outcome Scale Extended at discharge (P = 0.091) and at 1 y (P = 0.055). In conclusion, Hp2-2 phenotype is an independent risk factor for the development of both focal and global CV and also predicts poor functional outcomes and mortality after aSAH. Hp phenotyping may serve as a clinically useful tool in the critical care management of aSAH patients by allowing for early prediction of those patients who require increased vigilance due to their inherent genetic risk for the development of CV and resulting DCI and poor outcomes.


Asunto(s)
Angiografía Cerebral , Genotipo , Haptoglobinas/genética , Hemorragia Subaracnoidea , Vasoespasmo Intracraneal , Adulto , Anciano , Supervivencia sin Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Hemorragia Subaracnoidea/diagnóstico por imagen , Hemorragia Subaracnoidea/genética , Hemorragia Subaracnoidea/mortalidad , Tasa de Supervivencia , Vasoespasmo Intracraneal/diagnóstico por imagen , Vasoespasmo Intracraneal/genética , Vasoespasmo Intracraneal/mortalidad
9.
South Med J ; 110(7): 466-474, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28679016

RESUMEN

OBJECTIVES: Although disparities in stroke care and outcomes have been well documented nationally, state-based registries to monitor acute stroke care in Florida (FL) and Puerto Rico (PR) have not been established. The FL-PR Collaboration to Reduce Stroke Disparities (CReSD) was developed to evaluate race-ethnicity and regional disparities in stroke care performance. The objective of this study was to assess and compare hospital characteristics within a large quality improvement registry to identify characteristics associated with better outcomes for acute ischemic stroke care. METHODS: Trained personnel from 78 FL-PR CReSD hospitals (69 FL, 9 PR) completed a 50-item survey assessing institutional characteristics across seven domains: acute stroke care resource availability, emergency medical services integration, stroke center certification, data collection and use, quality improvement processes, FL-PR CReSD recruitment incentives, and hospital infrastructure. RESULTS: The rate of survey completion was 100%. Differences were observed both within FL and between FL and PR. Years participating in Get With The Guidelines-Stroke (8.9 ± 2.6 years FL vs 4.8 ± 2.4 years PR, P < 0.0001) and proportion of hospitals with any stroke center certification (94.2% FL vs 11.1% PR, P < 0.0001) showed the largest variations. Smaller hospital size, fewer years in Get With The Guidelines-Stroke, and lack of stroke center designation and acute stroke care practice implementation may contribute to poorer outcomes. CONCLUSIONS: Results from our survey indicated variability in hospital- and system-level characteristics in stroke care across hospitals in Florida and Puerto Rico. Identification of these variations, which may explain potential disparities, can help clinicians understand gaps in stroke care and outcomes and targeted interventions to reduce identified disparities can be implemented.


Asunto(s)
Disparidades en Atención de Salud/etnología , Disparidades en Atención de Salud/estadística & datos numéricos , Hospitales Especializados/organización & administración , Colaboración Intersectorial , Accidente Cerebrovascular/etnología , Accidente Cerebrovascular/terapia , Florida , Adhesión a Directriz , Encuestas de Atención de la Salud , Disparidades en Atención de Salud/tendencias , Hospitales Especializados/tendencias , Humanos , Evaluación de Resultado en la Atención de Salud/estadística & datos numéricos , Puerto Rico , Mejoramiento de la Calidad/organización & administración , Mejoramiento de la Calidad/tendencias , Sistema de Registros , Accidente Cerebrovascular/epidemiología
10.
Lancet ; 383(9914): 333-41, 2014 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-24168957

RESUMEN

BACKGROUND: Early results of the Stenting and Aggressive Medical Management for Preventing Recurrent stroke in Intracranial Stenosis trial showed that, by 30 days, 33 (14·7%) of 224 patients in the stenting group and 13 (5·8%) of 227 patients in the medical group had died or had a stroke (percentages are product limit estimates), but provided insufficient data to establish whether stenting offered any longer-term benefit. Here we report the long-term outcome of patients in this trial. METHODS: We randomly assigned (1:1, stratified by centre with randomly permuted block sizes) 451 patients with recent transient ischaemic attack or stroke related to 70-99% stenosis of a major intracranial artery to aggressive medical management (antiplatelet therapy, intensive management of vascular risk factors, and a lifestyle-modification programme) or aggressive medical management plus stenting with the Wingspan stent. The primary endpoint was any of the following: stroke or death within 30 days after enrolment, ischaemic stroke in the territory of the qualifying artery beyond 30 days of enrolment, or stroke or death within 30 days after a revascularisation procedure of the qualifying lesion during follow-up. Primary endpoint analysis of between-group differences with log-rank test was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT 00576693. FINDINGS: During a median follow-up of 32·4 months, 34 (15%) of 227 patients in the medical group and 52 (23%) of 224 patients in the stenting group had a primary endpoint event. The cumulative probability of the primary endpoints was smaller in the medical group versus the percutaneous transluminal angioplasty and stenting (PTAS) group (p=0·0252). Beyond 30 days, 21 (10%) of 210 patients in the medical group and 19 (10%) of 191 patients in the stenting group had a primary endpoint. The absolute differences in the primary endpoint rates between the two groups were 7·1% at year 1 (95% CI 0·2 to 13·8%; p=0·0428), 6·5% at year 2 (-0·5 to 13·5%; p=0·07) and 9·0% at year 3 (1·5 to 16·5%; p=0·0193). The occurrence of the following adverse events was higher in the PTAS group than in the medical group: any stroke (59 [26%] of 224 patients vs 42 [19%] of 227 patients; p=0·0468) and major haemorrhage (29 [13%]of 224 patients vs 10 [4%] of 227 patients; p=0·0009). INTERPRETATION: The early benefit of aggressive medical management over stenting with the Wingspan stent for high-risk patients with intracranial stenosis persists over extended follow-up. Our findings lend support to the use of aggressive medical management rather than PTAS with the Wingspan system in high-risk patients with atherosclerotic intracranial arterial stenosis. FUNDING: National Institute of Neurological Disorders and Stroke (NINDS) and others.


Asunto(s)
Angioplastia/métodos , Arteriosclerosis Intracraneal/terapia , Inhibidores de Agregación Plaquetaria/uso terapéutico , Stents , Adulto , Anciano , Anciano de 80 o más Años , Angioplastia/efectos adversos , Aspirina/uso terapéutico , Estenosis Carotídea/complicaciones , Estenosis Carotídea/terapia , Clopidogrel , Femenino , Estudios de Seguimiento , Humanos , Arteriosclerosis Intracraneal/complicaciones , Ataque Isquémico Transitorio/etiología , Ataque Isquémico Transitorio/prevención & control , Masculino , Persona de Mediana Edad , Inhibidores de Agregación Plaquetaria/efectos adversos , Prevención Secundaria , Método Simple Ciego , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/prevención & control , Ticlopidina/análogos & derivados , Ticlopidina/uso terapéutico , Resultado del Tratamiento
11.
Nat Genet ; 38(4): 447-51, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16501573

RESUMEN

Potassium channel mutations have been described in episodic neurological diseases. We report that K+ channel mutations cause disease phenotypes with neurodevelopmental and neurodegenerative features. In a Filipino adult-onset ataxia pedigree, the causative gene maps to 19q13, overlapping the SCA13 disease locus described in a French pedigree with childhood-onset ataxia and cognitive delay. This region contains KCNC3 (also known as Kv3.3), encoding a voltage-gated Shaw channel with enriched cerebellar expression. Sequencing revealed two missense mutations, both of which alter KCNC3 function in Xenopus laevis expression systems. KCNC3(R420H), located in the voltage-sensing domain, had no channel activity when expressed alone and had a dominant-negative effect when co-expressed with the wild-type channel. KCNC3(F448L) shifted the activation curve in the negative direction and slowed channel closing. Thus, KCNC3(R420H) and KCNC3(F448L) are expected to change the output characteristics of fast-spiking cerebellar neurons, in which KCNC channels confer capacity for high-frequency firing. Our results establish a role for KCNC3 in phenotypes ranging from developmental disorders to adult-onset neurodegeneration and suggest voltage-gated K+ channels as candidates for additional neurodegenerative diseases.


Asunto(s)
Ataxia Cerebelosa/genética , Activación del Canal Iónico , Mutación Missense , Mutación , Canales de Potasio Shaw/genética , Secuencia de Aminoácidos , Animales , Humanos , Datos de Secuencia Molecular , Fenotipo , Canales de Potasio Shaw/química , Xenopus laevis
12.
Neurobiol Dis ; 71: 270-9, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25152487

RESUMEN

Spinocerebellar ataxia 13 (SCA13) is an autosomal dominant disease resulting from mutations in KCNC3 (Kv3.3), a voltage-gated potassium channel. The KCNC3(R420H) mutation was first identified as causative for SCA13 in a four-generation Filipino kindred with over 20 affected individuals. Electrophysiological analyses in oocytes previously showed that this mutation did not lead to a functional channel and displayed a dominant negative phenotype. In an effort to identify the molecular basis of this allelic form of SCA13, we first determined that human KCNC3(WT) and KCNC3(R420H) display disparate post-translational modifications, and the mutant protein has reduced complex glycan adducts. Immunohistochemical analyses demonstrated that KCNC3(R420H) was not properly trafficking to the plasma membrane and surface biotinylation demonstrated that KCNC3(R420H) exhibited only 24% as much surface expression as KCNC3(WT). KCNC3(R420H) trafficked through the ER but was retained in the Golgi. KCNC3(R420H) expression results in altered Golgi and cellular morphology. Electron microscopy of KCNC3(R420H) localization further supports retention in the Golgi. These results are specific to the KCNC3(R420H) allele and provide new insight into the molecular basis of disease manifestation in SCA13.


Asunto(s)
Arginina/genética , Histidina/genética , Líquido Intracelular/metabolismo , Mutación/genética , Canales de Potasio Shaw/genética , Degeneraciones Espinocerebelosas/genética , Animales , Animales Modificados Genéticamente , Biotinilación , Células COS , Cadherinas/metabolismo , Chlorocebus aethiops , Citoplasma/genética , Citoplasma/metabolismo , Drosophila , Proteínas de Drosophila/genética , Retículo Endoplásmico/metabolismo , Femenino , Humanos , Masculino , Oocitos , Procesamiento Proteico-Postraduccional , Transporte de Proteínas , Ataxias Espinocerebelosas/congénito , Degeneraciones Espinocerebelosas/metabolismo , Transfección
13.
N Engl J Med ; 365(11): 993-1003, 2011 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-21899409

RESUMEN

BACKGROUND: Atherosclerotic intracranial arterial stenosis is an important cause of stroke that is increasingly being treated with percutaneous transluminal angioplasty and stenting (PTAS) to prevent recurrent stroke. However, PTAS has not been compared with medical management in a randomized trial. METHODS: We randomly assigned patients who had a recent transient ischemic attack or stroke attributed to stenosis of 70 to 99% of the diameter of a major intracranial artery to aggressive medical management alone or aggressive medical management plus PTAS with the use of the Wingspan stent system. The primary end point was stroke or death within 30 days after enrollment or after a revascularization procedure for the qualifying lesion during the follow-up period or stroke in the territory of the qualifying artery beyond 30 days. RESULTS: Enrollment was stopped after 451 patients underwent randomization, because the 30-day rate of stroke or death was 14.7% in the PTAS group (nonfatal stroke, 12.5%; fatal stroke, 2.2%) and 5.8% in the medical-management group (nonfatal stroke, 5.3%; non-stroke-related death, 0.4%) (P=0.002). Beyond 30 days, stroke in the same territory occurred in 13 patients in each group. Currently, the mean duration of follow-up, which is ongoing, is 11.9 months. The probability of the occurrence of a primary end-point event over time differed significantly between the two treatment groups (P=0.009), with 1-year rates of the primary end point of 20.0% in the PTAS group and 12.2% in the medical-management group. CONCLUSIONS: In patients with intracranial arterial stenosis, aggressive medical management was superior to PTAS with the use of the Wingspan stent system, both because the risk of early stroke after PTAS was high and because the risk of stroke with aggressive medical therapy alone was lower than expected. (Funded by the National Institute of Neurological Disorders and Stroke and others; SAMMPRIS ClinicalTrials.gov number, NCT00576693.).


Asunto(s)
Arteriosclerosis Intracraneal/terapia , Ataque Isquémico Transitorio/terapia , Stents , Accidente Cerebrovascular/prevención & control , Anciano , Antihipertensivos/uso terapéutico , Aspirina/uso terapéutico , Clopidogrel , Terapia Combinada , Femenino , Estudios de Seguimiento , Conductas Relacionadas con la Salud , Humanos , Arteriosclerosis Intracraneal/tratamiento farmacológico , Hemorragias Intracraneales/epidemiología , Hemorragias Intracraneales/etiología , Ataque Isquémico Transitorio/tratamiento farmacológico , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Inhibidores de Agregación Plaquetaria/uso terapéutico , Stents/efectos adversos , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/terapia , Ticlopidina/análogos & derivados , Ticlopidina/uso terapéutico
14.
BMC Neurol ; 14: 62, 2014 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-24678735

RESUMEN

BACKGROUND: Takayasu arteritis (TA) is an idiopathic large-vessel vasculitis that can result in significant morbidity and mortality secondary to progressive stenosis and occlusion. Monitoring disease progression is crucial to preventing relapse, but is often complicated by the lack of clinical symptoms in the setting of active disease. Although acute phase reactants such as ESR and CRP are generally used as an indicator of inflammation and disease activity, mounting evidence suggests that these markers cannot reliably distinguish active from inactive TA. CASE PRESENTATION: We report a 24-year-old Hispanic female with a 5-year history of TA who presented with stroke-like symptoms and evidence of left MCA occlusion on imaging, despite a history of decreasing inflammatory markers. CTA revealed complete occlusion of the left common carotid artery, left subclavian, and left MCA from their origins. It also revealed a striking compensatory circulation supplying the left anterior circulation as well as the left subclavian as a response to progressive stenosis. CONCLUSION: Monitoring ESR and CRP levels alone may not be a reliable method to evaluate disease progression in patients with TA, and should be taken in context with both patient's clinical picture and the imaging. We recommend that serial imaging be performed regularly in the setting of active disease to monitor progression and allow for immediate therapy in response to evidence of disease advancement, with a relaxation of the imaging interval once the disease is presumed inactive.


Asunto(s)
Biomarcadores/sangre , Mediadores de Inflamación/sangre , Arteritis de Takayasu/diagnóstico , Sedimentación Sanguínea , Proteína C-Reactiva/análisis , Estenosis Carotídea/etiología , Estenosis Carotídea/terapia , Circulación Colateral/fisiología , Femenino , Humanos , Isquemia/etiología , Monitoreo Fisiológico , Accidente Cerebrovascular/etiología , Arteritis de Takayasu/fisiopatología , Adulto Joven
15.
J Stroke Cerebrovasc Dis ; 23(1): 17-24, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22818388

RESUMEN

BACKGROUND: Health care disparities exist between demographic groups with stroke. We examined whether patients of particular ethnicity or income levels experienced reduced access to or delays in receiving stroke care. METHODS: We studied all admissions for ischemic stroke in the Nationwide Inpatient Sample (NIS) database between 2002 and 2008. We used statistical models to determine whether median income or race were associated with intravenous (i.v.) thrombolysis treatment, in-hospital mortality, discharge disposition, hospital charges, and LOS in high- or low-volume hospitals. RESULTS: There were a total of 477,474 patients with ischemic stroke: 10,781 (2.3%) received i.v. thrombolysis, and 380,400 (79.7%) were treated in high-volume hospitals. Race (P < .0001) and median income (P < .001) were significant predictors of receiving i.v. thrombolysis, and minorities and low-income patients were less likely to receive i.v. thrombolysis. Median income was a predictor of access to high-volume hospitals (P < .0001), with wealthier patients more likely to be treated in high-volume hospitals, which had lower mortality rates (P = .0002). Patients in high-volume hospitals were 1.84 times more likely to receive i.v. thrombolysis (P < .0001). CONCLUSIONS: African Americans, Hispanics, and low median income patients are less likely to receive i.v. thrombolysis for ischemic stroke. Low median income patients are less likely to be treated at high-volume hospitals. High-volume hospitals have lower mortality rates and a higher likelihood of treating patients with i.v. thrombolysis. There is evidence for an influence of socioeconomic status and racial disparity in the treatment of ischemic stroke.


Asunto(s)
Isquemia Encefálica/terapia , Disparidades en Atención de Salud/estadística & datos numéricos , Renta/estadística & datos numéricos , Grupos Minoritarios/estadística & datos numéricos , Accidente Cerebrovascular/terapia , Anciano , Anciano de 80 o más Años , Isquemia Encefálica/epidemiología , Bases de Datos Factuales , Femenino , Precios de Hospital/estadística & datos numéricos , Mortalidad Hospitalaria , Hospitales/estadística & datos numéricos , Humanos , Pacientes Internos , Clasificación Internacional de Enfermedades , Tiempo de Internación , Masculino , Persona de Mediana Edad , Pacientes , Clase Social , Factores Socioeconómicos , Accidente Cerebrovascular/epidemiología , Terapia Trombolítica/estadística & datos numéricos , Resultado del Tratamiento , Estados Unidos/epidemiología
16.
Stroke ; 44(12): 3452-7, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24149008

RESUMEN

BACKGROUND AND PURPOSE: Spontaneous swallowing frequency has been described as an index of dysphagia in various health conditions. This study evaluated the potential of spontaneous swallow frequency analysis as a screening protocol for dysphagia in acute stroke. METHODS: In a cohort of 63 acute stroke cases, swallow frequency rates (swallows per minute [SPM]) were compared with stroke and swallow severity indices, age, time from stroke to assessment, and consciousness level. Mean differences in SPM were compared between patients with versus without clinically significant dysphagia. Receiver operating characteristic curve analysis was used to identify the optimal threshold in SPM, which was compared with a validated clinical dysphagia examination for identification of dysphagia cases. Time series analysis was used to identify the minimally adequate time period to complete spontaneous swallow frequency analysis. RESULTS: SPM correlated significantly with stroke and swallow severity indices but not with age, time from stroke onset, or consciousness level. Patients with dysphagia demonstrated significantly lower SPM rates. SPM differed by dysphagia severity. Receiver operating characteristic curve analysis yielded a threshold of SPM≤0.40 that identified dysphagia (per the criterion referent) with 0.96 sensitivity, 0.68 specificity, and 0.96 negative predictive value. Time series analysis indicated that a 5- to 10-minute sampling window was sufficient to calculate spontaneous swallow frequency to identify dysphagia cases in acute stroke. CONCLUSIONS: Spontaneous swallowing frequency presents high potential to screen for dysphagia in acute stroke without the need for trained, available personnel.


Asunto(s)
Trastornos de Deglución/diagnóstico , Deglución/fisiología , Accidente Cerebrovascular/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , Trastornos de Deglución/etiología , Trastornos de Deglución/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Accidente Cerebrovascular/fisiopatología , Factores de Tiempo
17.
Stroke ; 44(11): 3154-60, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23963330

RESUMEN

BACKGROUND AND PURPOSE: Dysphagia can lead to pneumonia and subsequent death after acute stroke. However, no prospective study has demonstrated reduced pneumonia prevalence after implementation of a dysphagia screen. METHODS: We performed a single-center prospective interrupted time series trial of a quality initiative to improve dysphagia screening. Subjects included all patients with ischemic or hemorrhagic stroke admitted to our institution over 42 months with a 31-month (n=1686) preintervention and an 11-month (n=648) postintervention period. The intervention consisted of a dysphagia protocol with a nurse-administered bedside dysphagia screen and a reflexive rapid clinical swallow evaluation by a speech pathologist. RESULTS: The dysphagia initiative increased the percentage of patients with stroke screened from 39.3% to 74.2% (P<0.001). Furthermore, this initiative coincided with a drop in hospital-acquired pneumonia from 6.5% to 2.8% among patients with stroke (P<0.001). Patients admitted postinitiative had 57% lower odds of pneumonia, after controlling for multiple confounds (odds ratio=0.43; confidence interval, 0.255-0.711; P=0.0011). The best predictors of pneumonia were stroke type (P<0.0001), oral intake status (P<0.0001), dysphagia screening status (P=0.0037), and hospitalization before the beginning of the quality improvement initiative (P=0.0449). CONCLUSIONS: A quality improvement initiative using a nurse-administered bedside screen with rapid bedside swallow evaluation by a speech pathologist improves screening compliance and correlates with decreased prevalence of pneumonia among patients with stroke.


Asunto(s)
Infección Hospitalaria/epidemiología , Trastornos de Deglución/diagnóstico , Neumonía/epidemiología , Neumonía/prevención & control , Accidente Cerebrovascular/complicaciones , Anciano , Isquemia Encefálica/complicaciones , Isquemia Encefálica/terapia , Infección Hospitalaria/prevención & control , Deglución , Femenino , Humanos , Hemorragias Intracraneales/complicaciones , Hemorragias Intracraneales/terapia , Masculino , Tamizaje Masivo/métodos , Persona de Mediana Edad , Oportunidad Relativa , Prevalencia , Estudios Prospectivos , Calidad de la Atención de Salud , Accidente Cerebrovascular/terapia , Encuestas y Cuestionarios
18.
Cerebellum ; 12(6): 932-6, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23912307

RESUMEN

The p.Arg420His allelic form of spinocerebellar ataxia type 13 has been reported in a large Filipino kindred, as well as three European index cases, one with an affected offspring. Haplotype analysis has confirmed independent mutational events. All individuals share adult-onset, predominantly cerebellar signs and a slowly progressive course. However, a comprehensive phenotypic description has yet to be published on SCA13(p.Arg420His). In this study, we present the results of a detailed neurological clinical and diagnostic testing on 21 mutation-positive members of a four-generation Filipino family to further define this disease, aiding diagnosis and prognosis.


Asunto(s)
Arginina/genética , Histidina/genética , Mutación/genética , Canales de Potasio Shaw/genética , Degeneraciones Espinocerebelosas/genética , Degeneraciones Espinocerebelosas/fisiopatología , Adulto , Cerebelo/patología , Salud de la Familia , Femenino , Ligamiento Genético , Genotipo , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Fenotipo , Filipinas , Ataxias Espinocerebelosas/congénito , Degeneraciones Espinocerebelosas/patología
19.
Stroke ; 43(10): 2682-8, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22984008

RESUMEN

BACKGROUND AND PURPOSE: Enrollment in the Stenting and Aggressive Medical Management for Preventing Recurrent stroke in Intracranial Stenosis (SAMMPRIS) trial was halted due to the high risk of stroke or death within 30 days of enrollment in the percutaneous transluminal angioplasty and stenting arm relative to the medical arm. This analysis focuses on the patient and procedural factors that may have been associated with periprocedural cerebrovascular events in the trial. METHODS: Bivariate and multivariate analyses were performed to evaluate whether patient and procedural variables were associated with cerebral ischemic or hemorrhagic events occurring within 30 days of enrollment (termed periprocedural) in the percutaneous transluminal angioplasty and stenting arm. RESULTS: Of 224 patients randomized to percutaneous transluminal angioplasty and stenting, 213 underwent angioplasty alone (n=5) or with stenting (n=208). Of these, 13 had hemorrhagic strokes (7 parenchymal, 6 subarachnoid), 19 had ischemic stroke, and 2 had cerebral infarcts with temporary signs within the periprocedural period. Ischemic events were categorized as perforator occlusions (13), embolic (4), mixed perforator and embolic (2), and delayed stent occlusion (2). Multivariate analyses showed that higher percent stenosis, lower modified Rankin score, and clopidogrel load associated with an activated clotting time above the target range were associated (P ≤ 0.05) with hemorrhagic stroke. Nonsmoking, basilar artery stenosis, diabetes, and older age were associated (P ≤ 0.05) with ischemic events. CONCLUSIONS: Periprocedural strokes in SAMMPRIS had multiple causes with the most common being perforator occlusion. Although risk factors for periprocedural strokes could be identified, excluding patients with these features from undergoing percutaneous transluminal angioplasty and stenting to lower the procedural risk would limit percutaneous transluminal angioplasty and stenting to a small subset of patients. Moreover, given the small number of events, the present data should be used for hypothesis generation rather than to guide patient selection in clinical practice. Clinical Trial Registration Information- URL: http://clinicaltrials.gov. Unique Identifier: NCT00576693.


Asunto(s)
Angioplastia/efectos adversos , Constricción Patológica/cirugía , Periodo Perioperatorio , Stents/efectos adversos , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/prevención & control , Anciano , Angioplastia/instrumentación , Angioplastia/métodos , Constricción Patológica/complicaciones , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Análisis Multivariante , Recurrencia , Factores de Riesgo , Accidente Cerebrovascular/etiología , Factores de Tiempo , Resultado del Tratamiento
20.
Neurosurg Focus ; 32(2): E1, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22296678

RESUMEN

The overall incidence of neurological complications due to infective endocarditis is as high as 40%, with embolic infarcts more common than hemorrhagic strokes. The standard of care for typical strokes does not apply to infective endocarditis because there is a substantial risk of hemorrhage with thrombolysis. In the last decade there have been multiple case reports of intravenous and intraarterial thrombolysis with successful outcomes for acute strokes with related infective endocarditis, but successful endovascular interventions for acute strokes associated with infective endocarditis are rarely reported. To the authors' knowledge, this report is the first case in the literature to use a mechanical retrieval device in successful vegetation retrieval in an infective endocarditis acute stroke. Although an interventional approach for treatment of acute stroke related to infective endocarditis is a promising option, it is controversial and a cautious clinical decision should be made on a case-by-case basis. The authors conclude that this approach can be tested in a case series with matched controls, because this condition is rare and a randomized clinical trial is not a realistic option.


Asunto(s)
Endocarditis/complicaciones , Endocarditis/cirugía , Procedimientos Endovasculares/métodos , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/cirugía , Anciano , Endocarditis/diagnóstico , Femenino , Humanos , Accidente Cerebrovascular/diagnóstico
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