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1.
Cell ; 186(19): 4172-4188.e18, 2023 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-37633267

RESUMEN

Selective clearance of organelles, including endoplasmic reticulum (ER) and mitochondria, by autophagy plays an important role in cell health. Here, we describe a developmentally programmed selective ER clearance by autophagy. We show that Parkinson's disease-associated PINK1, as well as Atl, Rtnl1, and Trp1 receptors, regulate ER clearance by autophagy. The E3 ubiquitin ligase Parkin functions downstream of PINK1 and is required for mitochondrial clearance while having the opposite function in ER clearance. By contrast, Keap1 and the E3 ubiquitin ligase Cullin3 function downstream of PINK1 to regulate ER clearance by influencing Rtnl1 and Atl. PINK1 regulates a change in Keap1 localization and Keap1-dependent ubiquitylation of the ER-phagy receptor Rtnl1 to facilitate ER clearance. Thus, PINK1 regulates the selective clearance of ER and mitochondria by influencing the balance of Keap1- and Parkin-dependent ubiquitylation of substrates that determine which organelle is removed by autophagy.


Asunto(s)
Retículo Endoplásmico , Factor 2 Relacionado con NF-E2 , Retículo Endoplásmico/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch , Proteínas Quinasas , Ubiquitina-Proteína Ligasas , Drosophila melanogaster , Animales
2.
J Neurosci ; 43(1): 28-55, 2023 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-36446587

RESUMEN

Developing neurons must meet core molecular, cellular, and temporal requirements to ensure the correct formation of synapses, resulting in functional circuits. However, because of the vast diversity in neuronal class and function, it is unclear whether or not all neurons use the same organizational mechanisms to form synaptic connections and achieve functional and morphologic maturation. Moreover, it remains unknown whether neurons united in a common goal and comprising the same sensory circuit develop on similar timescales and use identical molecular approaches to ensure the formation of the correct number of synapses. To begin to answer these questions, we took advantage of the Drosophila antennal lobe (AL), a model olfactory circuit with remarkable genetic access and synapse-level resolution. Using tissue-specific genetic labeling of active zones, we performed a quantitative analysis of synapse formation in multiple classes of neurons of both sexes throughout development and adulthood. We found that olfactory receptor neurons (ORNs), projection neurons (PNs), and local interneurons (LNs) each have unique time courses of synaptic development, addition, and refinement, demonstrating that each class follows a distinct developmental program. This raised the possibility that these classes may also have distinct molecular requirements for synapse formation. We genetically altered neuronal activity in each neuronal subtype and observed differing effects on synapse number based on the neuronal class examined. Silencing neuronal activity in ORNs, PNs, and LNs impaired synaptic development but only in ORNs did enhancing neuronal activity influence synapse formation. ORNs and LNs demonstrated similar impairment of synaptic development with enhanced activity of a master kinase, GSK-3ß, suggesting that neuronal activity and GSK-3ß kinase activity function in a common pathway. ORNs also, however, demonstrated impaired synaptic development with GSK-3ß loss-of-function, suggesting additional activity-independent roles in development. Ultimately, our results suggest that the requirements for synaptic development are not uniform across all neuronal classes with considerable diversity existing in both their developmental time frames and molecular requirements. These findings provide novel insights into the mechanisms of synaptic development and lay the foundation for future work determining their underlying etiologies.SIGNIFICANCE STATEMENT Distinct olfactory neuron classes in Drosophila develop a mature synaptic complement over unique timelines and using distinct activity-dependent and molecular programs, despite having the same generalized goal of olfactory sensation.


Asunto(s)
Neuronas Receptoras Olfatorias , Animales , Femenino , Masculino , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Neuronas Receptoras Olfatorias/fisiología , Drosophila/fisiología , Olfato/fisiología , Sinapsis/fisiología , Vías Olfatorias/fisiología
3.
J Biol Chem ; 298(12): 102689, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36370844

RESUMEN

ATP-binding cassette (ABC) multidrug transporters are large, polytopic membrane proteins that exhibit astonishing promiscuity for their transport substrates. These transporters unidirectionally efflux thousands of structurally and functionally distinct compounds. To preclude the reentry of xenobiotic molecules via the drug-binding pocket, these proteins contain a highly conserved molecular gate, essentially allowing the transporters to function as molecular diodes. However, the structure-function relationship of these conserved gates and gating regions are not well characterized. In this study, we combine recent single-molecule, cryo-EM data with genetic and biochemical analyses of residues in the gating region of the yeast multidrug transporter Pdr5, the founding member of a large group of clinically relevant asymmetric ABC efflux pumps. Unlike the symmetric ABCG2 efflux gate, the Pdr5 counterpart is highly asymmetric, with only four (instead of six) residues comprising the gate proper. However, other residues in the near vicinity are essential for the gating activity. Furthermore, we demonstrate that residues in the gate and in the gating regions have multiple functions. For example, we show that Ile-685 and Val-1372 are required not only for successful efflux but also for allosteric inhibition of Pdr5 ATPase activity. Our investigations reveal that the gating region residues of Pdr5, and possibly other ABCG transporters, play a role not only in molecular gating but also in allosteric regulation, conformational switching, and protein folding.


Asunto(s)
Transportadoras de Casetes de Unión a ATP , Proteínas de Saccharomyces cerevisiae , Transportadoras de Casetes de Unión a ATP/genética , Transportadoras de Casetes de Unión a ATP/metabolismo , Pliegue de Proteína , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
4.
Stroke ; 53(5): 1651-1656, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34865511

RESUMEN

BACKGROUND: Prehospital automated large vessel occlusion (LVO) detection in Mobile Stroke Units (MSUs) could accelerate identification and treatment of patients with LVO acute ischemic stroke. Here, we evaluate the performance of a machine learning (ML) model on CT angiograms (CTAs) obtained from 2 MSUs to detect LVO. METHODS: Patients evaluated on MSUs in Houston and Los Angeles with out-of-hospital CTAs were identified. Anterior circulation LVO was defined as an occlusion of the intracranial internal carotid artery, middle cerebral artery (M1 or M2), or anterior cerebral artery vessels and determined by an expert human reader. A ML model to detect LVO was trained and tested on independent data sets consisting of in-hospital CTAs and then tested on MSU CTA images. Model performance was determined using area under the receiver-operator curve statistics. RESULTS: Among 68 patients with out-of-hospital MSU CTAs, 40% had an LVO. The most common occlusion location was the middle cerebral artery M1 segment (59%), followed by the internal carotid artery (30%), and middle cerebral artery M2 (11%). Median time from last known well to CTA imaging was 88.0 (interquartile range, 59.5-196.0) minutes. After training on 870 in-hospital CTAs, the ML model performed well in identifying LVO in a separate in-hospital data set of 441 images with area under receiver-operator curve of 0.84 (95% CI, 0.80-0.87). ML algorithm analysis time was under 1 minute. The performance of the ML model on the MSU CTA images was comparable with area under receiver-operator curve 0.80 (95% CI, 0.71-0.89). There was no significant difference in performance between the Houston and Los Angeles MSU CTA cohorts. CONCLUSIONS: In this study of patients evaluated on MSUs in 2 cities, a ML algorithm was able to accurately and rapidly detect LVO using prehospital CTA acquisitions.


Asunto(s)
Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Angiografía , Angiografía por Tomografía Computarizada/métodos , Humanos , Aprendizaje Automático , Accidente Cerebrovascular/diagnóstico por imagen , Tomografía Computarizada por Rayos X
6.
Stroke ; 49(3): 565-572, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29459391

RESUMEN

BACKGROUND AND PURPOSE: Prehospital scales have been developed to identify patients with acute cerebral ischemia (ACI) because of large vessel occlusion (LVO) for direct routing to Comprehensive Stroke Centers (CSCs), but few have been validated in the prehospital setting, and their impact on routing of patients with intracranial hemorrhage has not been delineated. The purpose of this study was to validate the Los Angeles Motor Scale (LAMS) for LVO and CSC-appropriate (LVO ACI and intracranial hemorrhage patients) recognition and compare the LAMS to other scales. METHODS: The performance of the LAMS, administered prehospital by paramedics to consecutive ambulance trial patients, was assessed in identifying (1) LVOs among all patients with ACI and (2) CSC-appropriate patients among all suspected strokes. Additionally, the LAMS administered postarrival was compared concurrently with 6 other scales proposed for paramedic use and the full National Institutes of Health Stroke Scale. RESULTS: Among 94 patients, age was 70 (±13) and 49% female. Final diagnoses were ACI in 76% (because of LVO in 48% and non-LVO in 28%), intracranial hemorrhage in 19%, and neurovascular mimic in 5%. The LAMS administered by paramedics in the field performed moderately well in identifying LVO among patients with ACI (C statistic, 0.79; accuracy, 0.72) and CSC-appropriate among all suspected stroke transports (C statistic, 0.80; accuracy, 0.72). When concurrently performed in the emergency department postarrival, the LAMS showed comparable or better accuracy versus the 7 comparator scales, for LVO among ACI (accuracies LAMS, 0.70; other scales, 0.62-0.68) and CSC-appropriate (accuracies LAMS, 0.73; other scales, 0.56-0.73). CONCLUSIONS: The LAMS performed in the field by paramedics identifies LVO and CSC-appropriate patients with good accuracy. The LAMS performs comparably or better than more extended prehospital scales and the full National Institutes of Health Stroke Scale.


Asunto(s)
Isquemia Encefálica/diagnóstico , Índice de Severidad de la Enfermedad , Accidente Cerebrovascular/diagnóstico , Anciano , Anciano de 80 o más Años , Isquemia Encefálica/terapia , Femenino , Humanos , Hemorragias Intracraneales/diagnóstico , Hemorragias Intracraneales/terapia , Masculino , Persona de Mediana Edad , Accidente Cerebrovascular/terapia
7.
Stroke ; 48(7): 1901-1907, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28583999

RESUMEN

BACKGROUND AND PURPOSE: Paramedic use of fixed-size lumen, gravity-controlled tubing to initiate intravenous infusions in the field may allow rapid start of neuroprotective therapy for acute stroke. In a large, multicenter trial, we evaluated its efficacy in attaining target serum levels of candidate neuroprotective agent magnesium sulfate and the relation of achieved magnesium levels to outcome. METHODS: The FAST-MAG phase 3 trial (Field Administration of Stroke Therapy - Magnesium) randomized 1700 patients within 2 hours of onset to paramedic-initiated, a 15-minute loading intravenous infusion of magnesium or placebo followed by a 24-hour maintenance dose. The drug delivery strategy included fixed-size lumen, gravity-controlled tubing for field drug administration, and a shrink-wrapped ambulance kit containing both the randomized field loading and hospital maintenance doses for seamless continuation. RESULTS: Among patient randomized to active treatment, magnesium levels in the first 72 hours were assessed 987 times in 572 patients. Mean patient age was 70 years (SD±14 years), and 45% were women. During the 24-hour period of active infusion, mean achieved serum level was 3.91 (±0.8), consistent with trial target. Mg levels were increased by older age, female sex, lower weight, height, body mass index, and estimated glomerular filtration rate, and higher blood urea nitrogen, hemoglobin, and higher hematocrit. Adjusted odds for clinical outcomes did not differ by achieved Mg level, including disability at 90 days, symptomatic hemorrhage, or death. CONCLUSIONS: Paramedic infusion initiation using gravity-controlled tubing permits rapid achievement of target serum levels of potential neuroprotective agents. The absence of association of clinical outcomes with achieved magnesium levels provides further evidence that magnesium is not biologically neuroprotective in acute stroke.


Asunto(s)
Auxiliares de Urgencia , Sulfato de Magnesio/farmacología , Magnesio/sangre , Fármacos Neuroprotectores/farmacología , Evaluación de Resultado en la Atención de Salud , Accidente Cerebrovascular/tratamiento farmacológico , Administración Intravenosa , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Sulfato de Magnesio/administración & dosificación , Masculino , Persona de Mediana Edad , Fármacos Neuroprotectores/administración & dosificación
8.
Stroke ; 48(5): 1389-1391, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28389617

RESUMEN

BACKGROUND AND PURPOSE: Novel methods are needed to reduce the disparity of Hispanic enrollment in stroke clinical trials. Prehospital enrollment using a dedicated Spanish language line may help overcome this bias. METHODS: Subjects or legally authorized representatives provided information on race and ethnicity for all cases enrolled in the FAST-MAG clinical trial (Field Administration of Stroke Therapy-Magnesium), a prehospital phase 3 randomized study of intravenous magnesium for neuroprotection. One of 2 in-ambulance cell phones (in English or Spanish) was used to obtain informed content in the field. We describe the yield and characteristics of subjects enrolled via Spanish line. RESULTS: There were 1700 subjects enrolled from 2005 to 2012, of which 402 (24%) identified as Hispanic ethnicity. Study racial makeup was 1325 (78%) white, 219 (13%) black, and 139 (8%) Asian. The dedicated Spanish line was used for 195 (12%) enrollments. Spanish-line enrollments were younger (65 versus 70 years old; P<0.001), more likely to identify as Hispanic (98% versus 14%; P<0.001), and more likely to present with intracerebral hemorrhage (36% versus 21%; P<0.001). CONCLUSIONS: The use of a dedicated Spanish language enrollment line allowed for greater enrollment of Hispanics, a population with significantly different baseline characteristics. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00059332.


Asunto(s)
Hemorragia Cerebral/terapia , Ensayos Clínicos como Asunto/normas , Asistencia Sanitaria Culturalmente Competente/normas , Hispánicos o Latinos , Selección de Paciente , Accidente Cerebrovascular/terapia , Anciano , Anciano de 80 o más Años , Investigación Biomédica/normas , California/etnología , Teléfono Celular , Auxiliares de Urgencia , Femenino , Humanos , Lenguaje , Magnesio/administración & dosificación , Magnesio/farmacología , Masculino , Persona de Mediana Edad , Fármacos Neuroprotectores/administración & dosificación , Fármacos Neuroprotectores/farmacología
9.
Stroke ; 48(2): 298-306, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-28087807

RESUMEN

BACKGROUND AND PURPOSE: The Los Angeles Motor Scale (LAMS) is a 3-item, 0- to 10-point motor stroke-deficit scale developed for prehospital use. We assessed the convergent, divergent, and predictive validity of the LAMS when performed by paramedics in the field at multiple sites in a large and diverse geographic region. METHODS: We analyzed early assessment and outcome data prospectively gathered in the FAST-MAG trial (Field Administration of Stroke Therapy-Magnesium phase 3) among patients with acute cerebrovascular disease (cerebral ischemia and intracranial hemorrhage) within 2 hours of onset, transported by 315 ambulances to 60 receiving hospitals. RESULTS: Among 1632 acute cerebrovascular disease patients (age 70±13 years, male 57.5%), time from onset to prehospital LAMS was median 30 minutes (interquartile range 20-50), onset to early postarrival (EPA) LAMS was 145 minutes (interquartile range 119-180), and onset to EPA National Institutes of Health Stroke Scale was 150 minutes (interquartile range 120-180). Between the prehospital and EPA assessments, LAMS scores were stable in 40.5%, improved in 37.6%, and worsened in 21.9%. In tests of convergent validity, against the EPA National Institutes of Health Stroke Scale, correlations were r=0.49 for the prehospital LAMS and r=0.89 for the EPA LAMS. Prehospital LAMS scores did diverge from the prehospital Glasgow Coma Scale, r=-0.22. Predictive accuracy (adjusted C statistics) for nondisabled 3-month outcome was as follows: prehospital LAMS, 0.76 (95% confidence interval 0.74-0.78); EPA LAMS, 0.85 (95% confidence interval 0.83-0.87); and EPA National Institutes of Health Stroke Scale, 0.87 (95% confidence interval 0.85-0.88). CONCLUSIONS: In this multicenter, prospective, prehospital study, the LAMS showed good to excellent convergent, divergent, and predictive validity, further establishing it as a validated instrument to characterize stroke severity in the field.


Asunto(s)
Técnicos Medios en Salud/normas , Servicios Médicos de Urgencia/normas , Índice de Severidad de la Enfermedad , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/epidemiología , Anciano , Anciano de 80 o más Años , California/epidemiología , Servicios Médicos de Urgencia/métodos , Auxiliares de Urgencia/normas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Reproducibilidad de los Resultados
10.
Stroke ; 47(1): 232-5, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26658446

RESUMEN

BACKGROUND AND PURPOSE: The enrollment yield and reasons for screen failure in prehospital stroke trials have not been well delineated. METHODS: The Field Administration of Stroke Therapy-Magnesium (FAST-MAG) trial identified patients for enrollment using a 2 stage screening process-paramedics in person followed by physician-investigators by cell phone. Outcomes of consecutive screening calls from paramedics to enrolling physician-investigators were prospectively recorded. RESULTS: From 2005 to 2012, 4458 phone calls were made by paramedics to physician-investigators, an average of 1 call per vehicle every 135.7 days. A total of 1700 (38.1%) calls resulted in enrollments. The rate of enrollment of stroke mimics was 3.9%. Among the 2758 patients not enrolled, 3140 reasons for screen failure were documented. The most common reasons for nonenrollment were >2 hours from last known well (17.2%), having a prestroke condition causing disability (16.1%), and absence of a consent provider (9.5%). Novel barriers for phone informed consent specific to the prehospital setting were infrequent, but included: cell phone connection difficulties (3.2%), patient being hard of hearing (1.4%), insufficient time to complete consent (1.3%), or severely dysarthric (1.3%). CONCLUSIONS: In this large, multicenter prehospital trial, nearly 40% of every calls from the field to physician-investigators resulted in trial enrollments. The most common reasons for nonenrollment were out of window last known well time, prestroke confounding medical condition, and absence of a consent provider. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00059332.


Asunto(s)
Servicios Médicos de Urgencia/métodos , Tamizaje Masivo/métodos , Selección de Paciente , Accidente Cerebrovascular/diagnóstico , Adulto , Servicios Médicos de Urgencia/normas , Femenino , Humanos , Masculino , Tamizaje Masivo/normas , Persona de Mediana Edad , Accidente Cerebrovascular/epidemiología , Resultado del Tratamiento
11.
J Mol Biol ; 436(15): 168473, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38311234

RESUMEN

Autophagy is used to degrade cytoplasmic materials, and is critical to maintain cell and organismal health in diverse animals. Here we discuss the regulation, utilization and impact of autophagy on development, including roles in oogenesis, spermatogenesis and embryogenesis in animals. We also describe how autophagy influences postembryonic development in the context of neuronal and cardiac development, wound healing, and tissue regeneration. We describe recent studies of selective autophagy during development, including mitochondria-selective autophagy and endoplasmic reticulum (ER)-selective autophagy. Studies of developing model systems have also been used to discover novel regulators of autophagy, and we explain how studies of autophagy in these physiologically relevant systems are advancing our understanding of this important catabolic process.


Asunto(s)
Autofagia , Desarrollo Embrionario , Animales , Humanos , Mitocondrias/metabolismo , Oogénesis , Retículo Endoplásmico/metabolismo , Espermatogénesis
12.
J Stroke Cerebrovasc Dis ; 22(8): e492-9, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23871701

RESUMEN

BACKGROUND: Pivotal clinical trials suggest that intravenous (IV) recombinant tissue plasminogen activator (rt-PA) benefits stroke patients regardless of the underlying etiology. Paradoxical strokes, presumed to be caused by fibrin-rich clots originating in the venous circulation, may respond better to fibrinolysis than other ischemic stroke subtypes. In this study, we compared the response with IV rt-PA in paradoxical stroke patients and other stroke subtypes. METHODS: In total, 486 patients treated with IV rt-PA at a single institution were retrospectively reviewed. Adjudication of stroke mechanism was based on chart review. Five major stroke mechanisms--cardioembolic, artery-to-artery emboli, lacunar, cryptogenic, and paradoxical--were identified by final diagnosis from chart reviews. Mimics, undefined etiology, and defined etiology not falling into the major mechanisms were excluded. Analysis of variance and general linear model were used to assess the differences between groups. RESULTS: A total of 323 patients were analyzed. We found significant differences in clinical outcome between stroke mechanisms, including discharge National Institutes of Health Stroke Scale (NIHSS) (P=.007), discharge Rankin (P=.011), discharge disposition (P=.000), and infarct volume (P=.007). Post hoc analysis showed that cardioembolic patients had the worst outcomes (discharge NIHSS score 11.12±12.26), whereas paradoxical strokes had the best outcomes (discharge NIHSS score 3.67±4.90), but these did not approach statistical significance. However, regression analysis showed that 4 variables--congestive heart failure, admission NIHSS, age, and mean infarct volume--rather than stroke mechanism were the true predictors of poor outcome. CONCLUSIONS: Paradoxical strokes had better outcomes after IV fibrinolysis than other ischemic stroke subtypes, but this difference is attributable to younger age and milder stroke severity on presentation.


Asunto(s)
Embolia Paradójica/tratamiento farmacológico , Fibrinolíticos/administración & dosificación , Foramen Oval Permeable/complicaciones , Embolia Intracraneal/tratamiento farmacológico , Accidente Cerebrovascular/tratamiento farmacológico , Terapia Trombolítica , Activador de Tejido Plasminógeno/administración & dosificación , Factores de Edad , Anciano , Arizona , Evaluación de la Discapacidad , Embolia Paradójica/diagnóstico , Embolia Paradójica/etiología , Femenino , Foramen Oval Permeable/diagnóstico , Insuficiencia Cardíaca/complicaciones , Humanos , Infusiones Intravenosas , Embolia Intracraneal/diagnóstico , Embolia Intracraneal/etiología , Modelos Lineales , Masculino , Persona de Mediana Edad , Alta del Paciente , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/diagnóstico , Factores de Tiempo , Resultado del Tratamiento
13.
Ann Neurol ; 70(2): 286-95, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21823156

RESUMEN

OBJECTIVE: Accurate assessment of Alzheimer's disease (AD), both presymptomatically and at different disease stages, will become increasingly important with the expanding elderly population. There are a number of indications that the immune system is engaged in AD. Here we explore the ability of an antibody-profiling technology to characterize AD and screen for peptides that may be used for a simple diagnostic test. METHODS: We developed an array-based system to profile the antibody repertoire of transgenic mice with cerebral amyloidosis (TG) and elderly individuals with or without AD. The array consists of 10,000 random sequence peptides (20-mers) capable of detecting antibody binding patterns, allowing the identification of peptides that mimic epitopes targeted by a donor's serum. RESULTS: TG mice exhibited a distinct immunoprofile compared to nontransgenic littermates. Further, we show that dementia patients, including autopsy-confirmed AD subjects, have distinguishable profiles compared to age-matched nondemented people. Using antibodies to different forms of Aß peptide and blocking protocols, we demonstrate that most of this signature is not due to the subject's antibodies raised against Aß. INTERPRETATION: We propose that "immunosignaturing" technology may have potential as a diagnostic tool in AD.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/inmunología , Técnicas de Diagnóstico Neurológico , Inmunoensayo/métodos , Péptidos beta-Amiloides/genética , Péptidos beta-Amiloides/inmunología , Animales , Anticuerpos/inmunología , Humanos , Ratones , Ratones Transgénicos , Análisis por Micromatrices/métodos , Péptidos/genética , Péptidos/inmunología , Proteínas tau/genética , Proteínas tau/inmunología
14.
J Stroke Cerebrovasc Dis ; 21(8): 839-43, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21640609

RESUMEN

BACKGROUND: Many patients with stroke-mimicking conditions receive treatment with intravenous fibrinolysis (IVF), a treatment associated with potentially serious complications. We sought to determine if any clinical or radiographic characteristics can help predict stroke mimics among IVF candidates. METHODS: This retrospective study was carried out at a single institution. Patients treated with intravenous recombinant tissue plasminogen activator (rt-PA; n = 193) were divided into 3 categories: acute ischemic stroke (n = 142), aborted stroke (n = 21), and stroke mimics (n = 30). Analysis of variance and the chi-square test were used to assess differences, while logistic regression models were computed to predict groups. RESULTS: Mimics treated with rt-PA did not experience complications (intracranial bleeding, systemic hemorrhage, or angioedema), and had better neurologic and functional outcomes than stroke patients (P < .05). Several variables helped differentiate strokes from mimics, including atherosclerosis on computed tomographic angiography (odds ratio [OR] 23.6; 95% confidence interval [CI] 8.4-66.2), atrial fibrillation (OR 11.4; 95% CI 1.5-86.3), age >50 years (OR 7.2; 95% CI 2.8-18.5), and focal weakness (OR 4.15; 95% CI 1.75-9.8). Other variables decreased chances of stroke: migraine history (OR 0.05; 95% CI 0.01-0.4), epilepsy (OR 0.13; 95% CI 0.02-0.8), paresthesia (OR 0.1; 95% CI 0.04-0.3), and precordialgia (OR 0.045; 95% CI 0.002-0.9). A regression model using focal weakness, computed tomographic angiography findings, and precordialgia had a 90.2% predictive accuracy. CONCLUSIONS: IVF has low complication rates in stroke mimics. Certain clinical characteristics appear predictive of stroke mimics, particularly normal computed tomographic angiography. If confirmed, this may help prevent giving IVF to patients without stroke.


Asunto(s)
Isquemia Encefálica/tratamiento farmacológico , Fibrinolíticos/administración & dosificación , Accidente Cerebrovascular/tratamiento farmacológico , Terapia Trombolítica , Activador de Tejido Plasminógeno/administración & dosificación , Procedimientos Innecesarios , Anciano , Anciano de 80 o más Años , Angioedema/inducido químicamente , Arizona , Isquemia Encefálica/diagnóstico , Angiografía Cerebral/métodos , Distribución de Chi-Cuadrado , Diagnóstico Diferencial , Servicio de Urgencia en Hospital , Femenino , Fibrinolíticos/efectos adversos , Humanos , Infusiones Intravenosas , Hemorragias Intracraneales/inducido químicamente , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Oportunidad Relativa , Selección de Paciente , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Factores de Riesgo , Accidente Cerebrovascular/diagnóstico , Terapia Trombolítica/efectos adversos , Activador de Tejido Plasminógeno/efectos adversos , Tomografía Computarizada por Rayos X
15.
Dev Cell ; 57(13): 1643-1660.e7, 2022 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-35654038

RESUMEN

Developing synapses mature through the recruitment of specific proteins that stabilize presynaptic and postsynaptic structure and function. Wnt ligands signaling via Frizzled (Fz) receptors play many crucial roles in neuronal and synaptic development, but whether and how Wnt and Fz influence synaptic maturation is incompletely understood. Here, we show that Fz2 receptor cleavage via the γ-secretase complex is required for postsynaptic development and maturation. In the absence of γ-secretase, Drosophila neuromuscular synapses fail to recruit postsynaptic scaffolding and cytoskeletal proteins, leading to behavioral deficits. Introducing presenilin mutations linked to familial early-onset Alzheimer's disease into flies leads to synaptic maturation phenotypes that are identical to those seen in null alleles. This conserved role for γ-secretase in synaptic maturation and postsynaptic development highlights the importance of Fz2 cleavage and suggests that receptor processing by proteins linked to neurodegeneration may be a shared mechanism with aspects of synaptic development.


Asunto(s)
Proteínas de Drosophila , Drosophila , Secretasas de la Proteína Precursora del Amiloide/genética , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Animales , Drosophila/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Receptores Frizzled/metabolismo , Receptores Wnt/metabolismo , Sinapsis/metabolismo
16.
Cereb Circ Cogn Behav ; 2: 100006, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-36324716

RESUMEN

White matter changes (WMC) are frequently observed in clinical practice, but their clinical relevance is often obscured by radiology reports that do not clearly convey a likely diagnosis. In this regard, two attitudes contribute to diagnostic confusion: a tendency to dismiss findings as trivial (i.e., using vague characterizations such as "non-specific" or "normal for age"), and a gratuitous dilatation of the differential diagnosis (i.e., routinely adding rare diseases to the list, such as vasculitis). Very often, the finding of WMC presents physicians with a very practical problem, which is to determine whether the underlying etiology is an autoimmune demyelinating disease such as multiple sclerosis (MS), or a vasculopathy such as small vessel cerebrovascular disease (SVCVD). The implications of this distinction are great, because the treatment and prognosis of these two syndromes are very different. Here, we describe the challenging case of a relatively young woman with dementia due to a combination of MS and cerebrovascular disease.

17.
Int J Stroke ; 16(6): 701-709, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33115382

RESUMEN

BACKGROUND: Intracranial atherosclerotic disease (ICAD) is one of the most challenging stroke etiologies, with frequent recurrences despite optimized medical management. Encephaloduroarteriosynangiosis (EDAS) is an indirect revascularization method that produces extra-cranial collaterals to intracranial vessels. We present the results of a phase-II trial of EDAS in intracranial atherosclerotic disease patients. AIMS: To evaluate the feasibility, safety, and preliminary efficacy of EDAS in intracranial atherosclerotic disease patients. METHODS: ERSIAS was a prospective objective-performance-criterion trial of EDAS plus intensive medical management (IMM) in intracranial atherosclerotic disease (ICAD) patients failing medical treatment. Primary endpoint was any stroke/death within 30-days post-surgery or stroke in the territory of the qualifying artery beyond 30 days. The primary analysis compared event rates through one year with an objective-performance-criterion based on a 10% reduction from the 20% rate in the intensive medical management arm of the stenting versus aggressive medical management for preventing recurrent stroke in intracranial stenosis trial (SAMMPRIS) in patients with poor collaterals. Event rates through two years were compared with propensity-score-matched (PSM) medically treated patients from SAMMPRIS and the carotid occlusion surgery study (COSS). RESULTS: During a median follow-up of 24.5 months, 5 (9.6%) of 52 patients had a primary endpoint event. The primary endpoint rate at one year met the threshold for nonfutility and advancement to phase III (<10%). In the sensitivity analysis, primary endpoint event rate at two years was lower than in PSM controls, 9.6% versus 21.2% (p < 0.07). Overall, 86% of EDAS-plus-intensive medical management patients were functionally independent at last follow-up and 89% demonstrated neovascularization. There were two (3.8%) surgical complications and no intracranial hemorrhages. CONCLUSION: ERSIAS phase II provides evidence of safety and strong signals of efficacy of EDAS-plus-intensive medical management, supporting advancement to a seamless phase-IIb/III trial. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov.NCT01819597.


Asunto(s)
Revascularización Cerebral , Arteriosclerosis Intracraneal , Accidente Cerebrovascular , Humanos , Arteriosclerosis Intracraneal/cirugía , Estudios Prospectivos , Accidente Cerebrovascular/terapia , Resultado del Tratamiento
18.
J Neurointerv Surg ; 13(11): 990-994, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33443113

RESUMEN

BACKGROUND: Targeted eloquence-based tissue reperfusion within the primary motor cortex may have a differential effect on disability as compared with traditional volume-based (thrombolysis in cerebral infarction, TICI) reperfusion after endovascular thrombectomy (EVT) in the setting of acute ischemic stroke (AIS). METHODS: We explored the impact of eloquent reperfusion (ER) within primary motor cortex (PMC) on clinical outcome (modified Rankin Scale, mRS) in AIS patients undergoing EVT. ER-PMC was defined as presence of flow on final digital subtraction angiography (DSA) within four main cortical branches, supplying the PMC (middle cerebral artery (MCA) - precentral, central, postcentral; anterior cerebral artery (ACA) - medial frontal branch arising from callosomarginal or pericallosal arteries) and graded as absent (0), partial (1), and complete (2). Prospectively collected data from two centers were analyzed. Multivariate analysis was conducted to assess the impact of ER-PMC on 90-day disability (mRS) among patients with anterior circulation occlusion who achieved partial reperfusion (TICI 2a and 2b). RESULTS: Among the 125 patients who met the study criteria, ER-PMC distribution was: absent (0) in 19/125 (15.2%); partial (1) in 52/125 (41.6%), and complete (2) in 54/125 (43.2%). TICI 2b was achieved in 102/125 (81.6%) and ER-PMC was substantially higher in those patients (P<0.001). In multivariate analysis, in addition to age and symptomatic intracranial hemorrhage, ER-PMC had a profound independent impact on 90-day disability (OR 6.10, P=0.001 for ER-PMC 1 vs 0 and OR 9.87, P<0.001 for ER-PMC 2 vs 0), while the extent of total partial reperfusion (TICI 2b vs 2a) was not related to 90-day mRS. CONCLUSIONS: Eloquent PMC-tissue reperfusion is a key determinant of functional outcome, with a greater impact than volume-based (TICI) degree of partial reperfusion alone. PMC-targeted revascularization among patients with partial reperfusion may further diminish post-stroke disability after EVT.


Asunto(s)
Isquemia Encefálica , Procedimientos Endovasculares , Corteza Motora , Accidente Cerebrovascular , Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/cirugía , Infarto Cerebral/diagnóstico por imagen , Infarto Cerebral/cirugía , Humanos , Corteza Motora/diagnóstico por imagen , Reperfusión , Estudios Retrospectivos , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/cirugía , Trombectomía , Terapia Trombolítica , Resultado del Tratamiento
19.
Cell Rep ; 31(7): 107654, 2020 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-32433963

RESUMEN

Adenosine-to-inosine RNA editing, catalyzed by adenosine deaminase acting on RNA (ADAR) enzymes, alters RNA sequences from those encoded by DNA. These editing events are dynamically regulated, but few trans regulators of ADARs are known in vivo. Here, we screen RNA-binding proteins for roles in editing regulation with knockdown experiments in the Drosophila brain. We identify zinc-finger protein at 72D (Zn72D) as a regulator of editing levels at a majority of editing sites in the brain. Zn72D both regulates ADAR protein levels and interacts with ADAR in an RNA-dependent fashion, and similar to ADAR, Zn72D is necessary to maintain proper neuromuscular junction architecture and fly mobility. Furthermore, Zn72D's regulatory role in RNA editing is conserved because the mammalian homolog of Zn72D, Zfr, regulates editing in mouse primary neurons. The broad and conserved regulation of ADAR editing by Zn72D in neurons sustains critically important editing events.


Asunto(s)
Adenosina Desaminasa/genética , Proteínas Portadoras/genética , Proteínas de Drosophila/genética , Neuronas/fisiología , Edición de ARN , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Adenosina Desaminasa/metabolismo , Animales , Animales Modificados Genéticamente , Encéfalo/citología , Encéfalo/metabolismo , Encéfalo/fisiología , Proteínas Portadoras/metabolismo , Drosophila , Proteínas de Drosophila/metabolismo , Femenino , Ratones , Ratones Endogámicos C57BL , Neuronas/metabolismo
20.
Cerebrovasc Dis ; 28(6): 539-44, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19844092

RESUMEN

BACKGROUND: Cellular phone conversations between on-scene patients or their legally authorized representatives (LARs) and off-scene enrolling physician-investigators require immediate and reliable connection systems to obtain explicit informed research consent in prehospital treatment trials. METHODS: The NIH Field Administration of Stroke Therapy-Magnesium (FAST-MAG) Trial implemented a voice-over-internet protocol (VOIP) simultaneous ring system (multiple investigator cell phones called simultaneously and first responder connected to call) to enable physician-investigators to elicit consent immediately from competent patients or LARs encountered by 228 ambulances enrolling patients in a multicenter prehospital stroke trial. For 1 month, the number, origin, duration, and yield of enrolling line calls were monitored prospectively. RESULTS: Six investigators were connected to 106 enrolling line calls, with no identified unanswered calls. Thirty-five percent of new patient calls yielded an enrollment. The most common reasons for non-enrollment were last known well >2 h (n = 7) and unconsentable patient without LAR available (n = 7). No non-enrollments were directly attributable to the VOIP system. In enrollments, consent was provided by the patient in 67% and a LAR in 33%. The duration of enrollment calls (mean +/- SD: 8.4 +/- 2.5 min, range 6-14) was longer than non-enrollment calls (5.5 +/- 3.5, range 2-13; p < 0.001). The median interval from last known well to study agent start was 46 min, and 70% were enrolled within 60 min of onset. CONCLUSIONS: The simultaneous ring system was reliable and effective, permitting enrollment of a substantial number of patients within the first hour after stroke onset. VOIP cellular networks with simultaneous ring are a preferred means of facilitating consent in prehospital treatment trials.


Asunto(s)
Teléfono Celular , Consentimiento Informado , Internet , Médicos , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Accidente Cerebrovascular/tratamiento farmacológico , Anciano , Bloqueadores de los Canales de Calcio/uso terapéutico , Femenino , Humanos , Los Angeles , Sulfato de Magnesio/uso terapéutico , Masculino , National Institutes of Health (U.S.) , Estudios Prospectivos , Factores de Tiempo , Estados Unidos
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