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1.
Am J Hum Genet ; 107(5): 963-976, 2020 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-33157009

RESUMEN

NCKAP1/NAP1 regulates neuronal cytoskeletal dynamics and is essential for neuronal differentiation in the developing brain. Deleterious variants in NCKAP1 have been identified in individuals with autism spectrum disorder (ASD) and intellectual disability; however, its clinical significance remains unclear. To determine its significance, we assemble genotype and phenotype data for 21 affected individuals from 20 unrelated families with predicted deleterious variants in NCKAP1. This includes 16 individuals with de novo (n = 8), transmitted (n = 6), or inheritance unknown (n = 2) truncating variants, two individuals with structural variants, and three with potentially disruptive de novo missense variants. We report a de novo and ultra-rare deleterious variant burden of NCKAP1 in individuals with neurodevelopmental disorders which needs further replication. ASD or autistic features, language and motor delay, and variable expression of intellectual or learning disability are common clinical features. Among inherited cases, there is evidence of deleterious variants segregating with neuropsychiatric disorders. Based on available human brain transcriptomic data, we show that NCKAP1 is broadly and highly expressed in both prenatal and postnatal periods and demostrate enriched expression in excitatory neurons and radial glias but depleted expression in inhibitory neurons. Mouse in utero electroporation experiments reveal that Nckap1 loss of function promotes neuronal migration during early cortical development. Combined, these data support a role for disruptive NCKAP1 variants in neurodevelopmental delay/autism, possibly by interfering with neuronal migration early in cortical development.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Trastorno del Espectro Autista/genética , Discapacidad Intelectual/genética , Discapacidades para el Aprendizaje/genética , Mutación , Proteínas Adaptadoras Transductoras de Señales/deficiencia , Adolescente , Animales , Trastorno del Espectro Autista/diagnóstico , Trastorno del Espectro Autista/patología , Corteza Cerebral/metabolismo , Corteza Cerebral/patología , Niño , Femenino , Expresión Génica , Genotipo , Células HEK293 , Humanos , Discapacidad Intelectual/diagnóstico , Discapacidad Intelectual/patología , Discapacidades para el Aprendizaje/diagnóstico , Discapacidades para el Aprendizaje/patología , Masculino , Ratones , Ratones Noqueados , Neuroglía/metabolismo , Neuroglía/patología , Neuronas/metabolismo , Neuronas/patología , Linaje , Fenotipo , Embarazo , Isoformas de Proteínas/antagonistas & inhibidores , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Transcriptoma , Adulto Joven
2.
Crit Care Med ; 51(6): 797-807, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-36988337

RESUMEN

OBJECTIVES: We implemented a computerized protocol for low tidal volume ventilation (LTVV) to improve management and outcomes of mechanically ventilated patients with, and without, the acute respiratory distress syndrome (ARDS). DESIGN: Pragmatic, nonrandomized stepped wedge type II hybrid implementation/effectiveness trial. SETTING: Twelve hospitals in an integrated healthcare system over a 2-year period. PATIENTS: Patients greater than or equal to 18 years old who had initiation of mechanical ventilation in the emergency department or ICU. We excluded patients who died or transitioned to comfort care on the day of admission to the ICU. We defined a subgroup of patients with ARDS for analysis. INTERVENTIONS: Implementation of ventilator protocols for LTVV in the ICU. MEASUREMENTS AND MAIN RESULTS: Our primary clinical outcome was ventilator-free days (VFDs) to day 28. Our primary process outcome was median initial set tidal volume. We included 8,692 mechanically ventilated patients, 3,282 (38%) of whom had ARDS. After implementation, set tidal volume reported as mL/kg predicted body weight decreased from median 6.1 mL/kg (interquartile range [IQR], 6.0-6.8 mL/kg) to 6.0 mL/kg (IQR, 6.0-6.6 mL/kg) ( p = 0.009). The percent of patients receiving LTVV (tidal volume ≤ 6.5 mL/kg) increased from 69.8% ( n = 1,721) to 72.5% ( n = 1,846) ( p = 0.036) after implementation. The percent of patients receiving greater than 8 mL/kg initial set tidal volume was reduced from 9.0% ( n = 222) to 6.7% ( n = 174) ( p = 0.005) after implementation. Among patients with ARDS, day 1 positive end-expiratory pressure increased from 6.7 to 8.0 cm H 2 O ( p < 0.001). We observed no difference in VFD (adjusted odds ratio, 1.06; 95% CI, 0.91-1.24; p = 0.44), or in secondary outcomes of length of stay or mortality, either within the main cohort or the subgroup of patients with ARDS. CONCLUSIONS: We observed improved adherence to optimal ventilator management with implementation of a computerized protocol and reduction in the number of patients receiving tidal volumes greater than 8 mL/kg. We did not observe improvement in clinical outcomes.


Asunto(s)
Síndrome de Dificultad Respiratoria , Insuficiencia Respiratoria , Humanos , Pulmón , Respiración con Presión Positiva/métodos , Respiración Artificial/métodos , Síndrome de Dificultad Respiratoria/terapia , Insuficiencia Respiratoria/terapia , Volumen de Ventilación Pulmonar
3.
Am J Hum Genet ; 103(5): 786-793, 2018 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-30343942

RESUMEN

PCGF2 encodes the polycomb group ring finger 2 protein, a transcriptional repressor involved in cell proliferation, differentiation, and embryogenesis. PCGF2 is a component of the polycomb repressive complex 1 (PRC1), a multiprotein complex which controls gene silencing through histone modification and chromatin remodelling. We report the phenotypic characterization of 13 patients (11 unrelated individuals and a pair of monozygotic twins) with missense mutations in PCGF2. All the mutations affected the same highly conserved proline in PCGF2 and were de novo, excepting maternal mosaicism in one. The patients demonstrated a recognizable facial gestalt, intellectual disability, feeding problems, impaired growth, and a range of brain, cardiovascular, and skeletal abnormalities. Computer structural modeling suggests the substitutions alter an N-terminal loop of PCGF2 critical for histone biding. Mutant PCGF2 may have dominant-negative effects, sequestering PRC1 components into complexes that lack the ability to interact efficiently with histones. These findings demonstrate the important role of PCGF2 in human development and confirm that heterozygous substitutions of the Pro65 residue of PCGF2 cause a recognizable syndrome characterized by distinctive craniofacial, neurological, cardiovascular, and skeletal features.

4.
Crit Care ; 23(1): 424, 2019 12 27.
Artículo en Inglés | MEDLINE | ID: mdl-31881909

RESUMEN

BACKGROUND: In patients with acute respiratory distress syndrome (ARDS), low tidal volume ventilation has been associated with reduced mortality. Driving pressure (tidal volume normalized to respiratory system compliance) may be an even stronger predictor of ARDS survival than tidal volume. We sought to study whether these associations hold true in acute respiratory failure patients without ARDS. METHODS: This is a retrospectively cohort analysis of mechanically ventilated adult patients admitted to ICUs from 12 hospitals over 2 years. We used natural language processing of chest radiograph reports and data from the electronic medical record to identify patients who had ARDS. We used multivariable logistic regression and generalized linear models to estimate associations between tidal volume, driving pressure, and respiratory system compliance with adjusted 30-day mortality using covariates of Acute Physiology Score (APS), Charlson Comorbidity Index (CCI), age, and PaO2/FiO2 ratio. RESULTS: We studied 2641 patients; 48% had ARDS (n = 1273). Patients with ARDS had higher mean APS (25 vs. 23, p < .001) but similar CCI (4 vs. 3, p = 0.6) scores. For non-ARDS patients, tidal volume was associated with increased adjusted mortality (OR 1.18 per 1 mL/kg PBW increase in tidal volume, CI 1.04 to 1.35, p = 0.010). We observed no association between driving pressure or respiratory compliance and mortality in patients without ARDS. In ARDS patients, both ΔP (OR1.1, CI 1.06-1.14, p < 0.001) and tidal volume (OR 1.17, CI 1.04-1.31, p = 0.007) were associated with mortality. CONCLUSIONS: In a large retrospective analysis of critically ill non-ARDS patients receiving mechanical ventilation, we found that tidal volume was associated with 30-day mortality, while driving pressure was not.


Asunto(s)
Respiración Artificial/mortalidad , Insuficiencia Respiratoria/fisiopatología , Volumen de Ventilación Pulmonar/fisiología , Anciano , Estudios de Cohortes , Femenino , Humanos , Idaho , Masculino , Persona de Mediana Edad , Respiración con Presión Positiva/mortalidad , Respiración con Presión Positiva/normas , Respiración Artificial/normas , Respiración Artificial/estadística & datos numéricos , Insuficiencia Respiratoria/mortalidad , Insuficiencia Respiratoria/terapia , Estudios Retrospectivos , Resultado del Tratamiento , Utah
5.
Crit Care Med ; 46(12): 1943-1952, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30277890

RESUMEN

OBJECTIVES: Low tidal volume (= tidal volume ≤ 6 mL/kg, predicted body weight) ventilation using volume control benefits patients with acute respiratory distress syndrome. Airway pressure release ventilation is an alternative to low tidal volume-volume control ventilation, but the release breaths generated are variable and can exceed tidal volume breaths of low tidal volume-volume control. We evaluate the application of a low tidal volume-compatible airway pressure release ventilation protocol that manages release volumes on both clinical and feasibility endpoints. DESIGN: We designed a prospective randomized trial in patients with acute hypoxemic respiratory failure. We randomized patients to low tidal volume-volume control, low tidal volume-airway pressure release ventilation, and traditional airway pressure release ventilation with a planned enrollment of 246 patients. The study was stopped early because of low enrollment and inability to consistently achieve tidal volumes less than 6.5 mL/kg in the low tidal volume-airway pressure release ventilation arm. Although the primary clinical study endpoint was PaO2/FIO2 on study day 3, we highlight the feasibility outcomes related to tidal volumes in both arms. SETTING: Four Intermountain Healthcare tertiary ICUs. PATIENTS: Adult ICU patients with hypoxemic respiratory failure anticipated to require prolonged mechanical ventilation. INTERVENTIONS: Low tidal volume-volume control, airway pressure release ventilation, and low tidal volume-airway pressure release ventilation. MEASUREMENTS AND MAIN RESULTS: We observed wide variability and higher tidal (release for airway pressure release ventilation) volumes in both airway pressure release ventilation (8.6 mL/kg; 95% CI, 7.8-9.6) and low tidal volume-airway pressure release ventilation (8.0; 95% CI, 7.3-8.9) than volume control (6.8; 95% CI, 6.2-7.5; p = 0.005) with no difference between airway pressure release ventilation and low tidal volume-airway pressure release ventilation (p = 0.58). Recognizing the limitations of small sample size, we observed no difference in 52 patients in day 3 PaO2/ FIO2 (p = 0.92). We also observed no significant difference between arms in sedation, vasoactive medications, or occurrence of pneumothorax. CONCLUSIONS: Airway pressure release ventilation resulted in release volumes often exceeding 12 mL/kg despite a protocol designed to target low tidal volume ventilation. Current airway pressure release ventilation protocols are unable to achieve consistent and reproducible delivery of low tidal volume ventilation goals. A large-scale efficacy trial of low tidal volume-airway pressure release ventilation is not feasible at this time in the absence of an explicit, generalizable, and reproducible low tidal volume-airway pressure release ventilation protocol.


Asunto(s)
Presión de las Vías Aéreas Positiva Contínua/métodos , Mortalidad Hospitalaria , Insuficiencia Respiratoria/mortalidad , Insuficiencia Respiratoria/terapia , Volumen de Ventilación Pulmonar/fisiología , Adulto , Anciano , Protocolos Clínicos , Estudios de Factibilidad , Femenino , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Estudios Prospectivos
7.
Ann Am Thorac Soc ; 20(10): 1483-1490, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37413692

RESUMEN

Rationale: Routine spontaneous awakening and breathing trial coordination (SAT/SBT) improves outcomes for mechanically ventilated patients, but adherence varies. Understanding barriers to and facilitators of consistent daily use of SAT/SBT (implementation determinants) can guide the development of implementation strategies to increase adherence to these evidence-based interventions. Objectives: We conducted an explanatory, sequential mixed-methods study to measure variation in the routine daily use of SAT/SBT and to identify implementation determinants that might explain variation in SAT/SBT use across 15 intensive care units (ICUs) in urban and rural locations within an integrated, community-based health system. Methods: We described the patient population and measured adherence to daily use of coordinated SAT/SBT from January to June 2021, selecting four sites with varied adherence levels for semistructured field interviews. We conducted key informant interviews with critical care nurses, respiratory therapists, and physicians/advanced practice clinicians (n = 55) from these four sites between October and December 2021 and performed content analysis to identify implementation determinants of SAT/SBT use. Results: The 15 sites had 1,901 ICU admissions receiving invasive mechanical ventilation (IMV) for ⩾24 hours during the measurement period. The mean IMV patient age was 58 years, and the median IMV duration was 5.3 days (interquartile range, 2.5-11.9). Coordinated SAT/SBT adherence (within 2 h) was estimated at 21% systemwide (site range, 9-68%). ICU clinicians were generally familiar with SAT/SBT but varied in their knowledge and beliefs about what constituted an evidence-based SAT/SBT. Clinicians reported that SAT/SBT coordination was difficult in the context of existing ICU workflows, and existing protocols did not explicitly define how coordination should be performed. The lack of an agreed-upon system-level measure for tracking daily use of SAT/SBT led to uncertainty regarding what constituted adherence. The effects of the COVID-19 pandemic increased clinician workloads, impacting performance. Conclusions: Coordinated SAT/SBT adherence varied substantially across 15 ICUs within an integrated, community-based health system. Implementation strategies that address barriers identified by this study, including knowledge deficits, challenges regarding workflow coordination, and the lack of performance measurement, should be tested in future hybrid implementation-effectiveness trials to increase adherence to daily use of coordinated SAT/SBT and minimize harm related to the prolonged use of mechanical ventilation and sedation.


Asunto(s)
Pandemias , Desconexión del Ventilador , Humanos , Persona de Mediana Edad , Desconexión del Ventilador/métodos , Respiración Artificial/métodos , Respiración , Unidades de Cuidados Intensivos
8.
Implement Sci ; 18(1): 45, 2023 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-37735443

RESUMEN

BACKGROUND: Intensive care unit (ICU) patients on mechanical ventilation often require sedation and analgesia to improve comfort and decrease pain. Prolonged sedation and analgesia, however, may increase time on mechanical ventilation, risk for ventilator associated pneumonia, and delirium. Coordinated interruptions in sedation [spontaneous awakening trials (SATs)] and spontaneous breathing trials (SBTs) increase ventilator-free days and improve mortality. Coordination of SATs and SBTs is difficult with substantial implementation barriers due to difficult-to-execute sequencing between nurses and respiratory therapists. Telehealth-enabled remote care has the potential to overcome these barriers and improve coordinated SAT and SBT adherence by enabling proactive high-risk patient monitoring, surveillance, and real-time assistance to frontline ICU teams. METHODS: The telehealth-enabled, real-time audit and feedback for clinician adherence (TEACH) study will determine whether adding a telehealth augmented real-time audit and feedback to a usual supervisor-led audit and feedback intervention will yield higher coordinated SAT and SBT adherence and more ventilator-free days in mechanically ventilated patients than a usual supervisor-led audit and feedback intervention alone in a type II hybrid effectiveness-implementation cluster-randomized clinical trial in 12 Intermountain Health hospitals with 15 ICUs. In the active comparator control group (six hospitals), the only intervention is the usual supervisor-led audit and feedback implementation. The telehealth-enabled support (TEACH) intervention in six hospitals adds real-time identification of patients eligible for a coordinated SAT and SBT and consultative input from telehealth respiratory therapists, nurses, and physicians to the bedside clinicians to promote adherence including real-time assistance with execution. All intubated and mechanically ventilated patients ≥ 16 years of age are eligible for enrollment except for patients who die on the day of intubation or have preexisting brain death. Based on preliminary power analyses, we plan a 36-month intervention period that includes a 90-day run-in period. Estimated enrollment in the final analysis is up to 9900 mechanically ventilated patients over 33 months. DISCUSSION: The TEACH study will enhance implementation science by providing insight into how a telehealth intervention augmenting a usual audit and feedback implementation may improve adherence to coordinated SAT and SBT and increase ventilator-free days. TRIAL REGISTRATION: Clinicaltrials.gov, NCT05141396 , registered 12/02/2021.


Asunto(s)
Telemedicina , Humanos , Retroalimentación , Dolor , Manejo del Dolor , Técnicos Medios en Salud
9.
JAMIA Open ; 5(2): ooac050, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35815095

RESUMEN

Objective: Computer-aided decision tools may speed recognition of acute respiratory distress syndrome (ARDS) and promote consistent, timely treatment using lung-protective ventilation (LPV). This study evaluated implementation and service (process) outcomes with deployment and use of a clinical decision support (CDS) synchronous alert tool associated with existing computerized ventilator protocols and targeted patients with possible ARDS not receiving LPV. Materials and Methods: We performed an explanatory mixed methods study from December 2019 to November 2020 to evaluate CDS alert implementation outcomes across 13 intensive care units (ICU) in an integrated healthcare system with >4000 mechanically ventilated patients annually. We utilized quantitative methods to measure service outcomes including CDS alert tool utilization, accuracy, and implementation effectiveness. Attitudes regarding the appropriateness and acceptability of the CDS tool were assessed via an electronic field survey of physicians and advanced practice providers. Results: Thirty-eight percent of study encounters had at least one episode of LPV nonadherence. Addition of LPV treatment detection logic prevented an estimated 1812 alert messages (41%) over use of disease detection logic alone. Forty-eight percent of alert recommendations were implemented within 2 h. Alert accuracy was estimated at 63% when compared to gold standard ARDS adjudication, with sensitivity of 85% and positive predictive value of 62%. Fifty-seven percent of survey respondents observed one or more benefits associated with the alert. Conclusion: Introduction of a CDS alert tool based upon ARDS risk factors and integrated with computerized ventilator protocol instructions increased visibility to gaps in LPV use and promoted increased adherence to LPV.

11.
Implement Sci Commun ; 1(1): 67, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32835225

RESUMEN

BACKGROUND: Lung-protective ventilation (LPV) improves outcomes for patients with acute respiratory distress syndrome (ARDS) through the administration of low tidal volumes (≤ 6.5 ml/kg predicted body weight [PBW]) with co-titration of positive end-expiratory pressure and fraction of inspired oxygen. Many patients with ARDS, however, are not managed with LPV. The purpose of this study was to understand the implementation barriers and facilitators to the use of LPV and a computerized LPV clinical decision support (CDS) tool in intensive care units (ICUs) in preparation for a pilot hybrid implementation-effectiveness clinical trial. METHODS: We performed an explanatory sequential mixed methods study from June 2018 to March 2019 to evaluate the variation in LPV adherence across 17 ICUs in an integrated healthcare system with > 4000 mechanically ventilated patients annually. We analyzed 47 key informant interviews of ICU physicians, respiratory therapists (RTs), and nurses in 3 of the ICUs using a qualitative content analysis paradigm to investigate site variation as defined by adherence level (low, medium, high) and to identify barriers and facilitators to LPV and LPV CDS tool use. RESULTS: Forty-two percent of patients had an initial set tidal volume of ≤ 6.5 ml/kg PBW during the measurement period (site range 21-80%). LPV CDS tool use was 28% (site range 6-91%). This study's main findings revealed multi-factorial facilitators and barriers to use that varied by ICU site adherence level. The primary facilitator was that LPV and the LPV CDS tool could be used on all mechanically ventilated patients. Barriers included a persistent gap between clinician attitudes regarding the use of LPV and actual use, the perceived loss of autonomy associated with using a computerized protocol, the nature of physician-RT interaction in ventilation management, and the lack of clear organization measures of success. CONCLUSIONS: Variation in adherence to LPV persists in ICUs within a healthcare delivery system that was an early adopter of LPV. Potentially promising strategies to increase adherence to LPV and the LPV CDS tool for ARDS patients include initiating low tidal ventilation on all mechanically ventilated patients, establishing and measuring adherence measures, and focused education addressing the physician-RT interaction. These strategies represent a blueprint for a future hybrid implementation-effectiveness trial.

13.
Artículo en Inglés | MEDLINE | ID: mdl-23944734

RESUMEN

Amyotrophic lateral sclerosis (ALS) is a degenerative motor neuron disease leading to progressive paralysis that is generally fatal. Only 10% of cases are familial, a subset of which overlaps with frontotemporal dementia (FTD). Up to half of ALS patients have cognitive impairment, with 15% meeting the criteria for FTD. Clinical sequencing of UBQLN2 in a family with X-linked FTD/ALS with suspected incomplete penetrance, manifesting in both genders, revealed a P506S mutation in. Affected individuals were diagnosed with various conditions including hereditary spastic paraplegia (HSP), bulbar palsy and multiple sclerosis. The mutation in UBQLN2 was first identified in a 35-year-old female who presented with one year of progressive dysarthria, dyspnea, dysphagia, and cognitive decline. EMG suggested early motor neuron disease with prominent bulbar involvement. Her cognition declined rapidly and she developed extremity weakness. Her brother, initially diagnosed with HSP, and her second cousin, with primary lateral sclerosis, also have a P506S mutation in UBQLN2. In conclusion, the P506S mutation in UBQLN2 can affect both males and females and displays great phenotypic variability within the same family. Females can potentially have a more severe and rapidly progressive presentation than their male relatives. Additionally, the P506S mutation can also cause an FTD phenotype.


Asunto(s)
Esclerosis Amiotrófica Lateral/diagnóstico , Esclerosis Amiotrófica Lateral/genética , Proteínas de Ciclo Celular/genética , Demencia Frontotemporal/diagnóstico , Demencia Frontotemporal/genética , Variación Genética/genética , Mutación/genética , Penetrancia , Ubiquitinas/genética , Proteínas Adaptadoras Transductoras de Señales , Adulto , Proteínas Relacionadas con la Autofagia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Linaje , Adulto Joven
14.
Brain Dev ; 34(9): 750-5, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22277191

RESUMEN

Rett syndrome (OMIM 312750) is a progressive, X-linked neurodevelopmental disorder caused by mutations in the MECP2 gene located on chromosome Xq28. The disorder is characterized by a period of normal development during the first 6-18months of life, followed by gradual loss of skills already gained, such as speech and purposeful movement of the hands. The majority of cases are sporadic and represent "de novo" mutations. In this study we summarize the results of diagnostic testing of 30 patients with Rett syndrome (RTT) or mental retardation of unknown etiology using bidirectional sequencing of the open reading frame of the MECP2 gene. Twenty different variants were identified in those patients including 12 missense (R133C, P152R, T158M, V300I, I303M, R306C, T311M, R344W, A358T, P384L, A443T, V481M), four nonsense (R168X, K192X, R255X, R270X), two deletion (E137_L386del, I293_S350del), and two frameshift (S291QfsX26, G343AfsX6) mutations. Seven of the twenty variants identified were novel mutations (E137_L386del, K192X, S291QfsX26, G343AfsX6, I293_S350del, P384L, and A443T). In the cases with novel or non-recurrent missense mutations, family studies were performed to investigate genotype-phenotype correlations. Our results demonstrate the importance of family studies and highlight the complexity of interpretation of MECP2 alterations, which may or may not be disease-associated.


Asunto(s)
Proteína 2 de Unión a Metil-CpG/genética , Mutación Missense/genética , Patología Molecular/métodos , Síndrome de Rett/diagnóstico , Síndrome de Rett/genética , Salud de la Familia , Estudios de Asociación Genética , Humanos , Masculino
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