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1.
Psychosomatics ; 59(4): 369-378, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29580558

RESUMEN

BACKGROUND: Neurological conditions carry a high risk of depression. Given this risk, the Neurological Institute (NI) at Cleveland Clinic has initiated systematic screening for depression using the 9-item Patient Health Questionnaire-9 (PHQ-9) embedded within its electronic medical record and its data capture system, the Knowledge Program (KP)1. OBJECTIVE: We sought to (1) estimate the prevalence of depression among patients with epilepsy, stroke, and multiple sclerosis (MS); (2) identify risk factors for depression within each disease; and (3) determine differential risks and predictors across neurological disorders. METHODS: The KP1 database provided information on approximately 23,000 visits involving 7946 outpatients with epilepsy, stroke, or MS seen in neurology specialty clinics. The primary outcome measure was depression as defined as a PHQ-9 ≥ 10. RESULTS: Overall, the point prevalence of depression was 29.0%. For stroke, epilepsy, and MS, prevalence of depression was 23% (95% CI: 21-25%), 33% (95% CI: 31-35%), and 29% (95% CI: 28-30%), respectively. For all 3 conditions, increasing disease severity and decreased health-related quality of life were independent predictors of depression. In multivariable models, there was a significant interaction between age and condition, and condition with disease severity. In stroke and MS, increasing age was associated with reduced odds for depression, whereas in epilepsy, increasing age was associated with an increased odds for depression. CONCLUSIONS: Although depression is common among patients with neurological disorders, our data suggest that predictors of depression such as age and disease severity varied by condition, supporting important possible phenomenological and pathophysiological differences of depression across these neurological conditions.


Asunto(s)
Trastorno Depresivo/diagnóstico , Trastorno Depresivo/epidemiología , Epilepsia/epidemiología , Esclerosis Múltiple/epidemiología , Accidente Cerebrovascular/epidemiología , Encuestas y Cuestionarios , Adulto , Comorbilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ohio , Prevalencia
2.
Value Health ; 20(8): 1143-1149, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28964447

RESUMEN

BACKGROUND: Patient-reported outcome performance measures (PRO-PMs) incorporate outcomes from the patient's perspective into performance measures and may have great potential to impact health care. The various patient-reported outcome measures (PROMs) used to assess the same outcome challenge widespread use of PRO-PMs. A potential solution is to statistically link PROMs to provide equivalent PRO-PM conclusions to be drawn regardless of which PROM was used. OBJECTIVES: To determine the level of agreement in the performance of two depression-related PRO-PMs assessed using the nine-item Patient Health Questionnaire (PHQ-9) depression scale and the eight-item Patient-Reported Outcomes Measurement Information System (PROMIS) Depression short form and the PHQ-9 cocalibrated on the PROMIS metric. METHODS: We conducted a retrospective cohort study of patients who visited one of eight ambulatory neurological and psychiatric clinics at the Cleveland Clinic between January 23 and June 15, 2012, and who completed both the PHQ-9 and PROMIS Depression scales at the same visit. The level of agreement was measured between PRO-PM performance assessed with standard scoring of the PHQ-9, the PROMIS cocalibrated scoring of the PHQ-9, and the PROMIS score for two depression-related PRO-PMs. RESULTS: Of the 5736 enrolled patients, 701 had PROMs from two or more visits. Differences in performance of the depression remission PRO-PM ranged from 0.4% to 2.1%, and differences in the progress toward remission PRO-PM ranged from 0.9% to 5.1%, depending on which depression score was used. CONCLUSIONS: There was a high level of agreement in the PRO-PM for depression when incorporating different PROMs. These findings support the ability to use linkage of scale scores to assess performance of PRO-PMs with different PROMs.


Asunto(s)
Depresión/diagnóstico , Medición de Resultados Informados por el Paciente , Encuestas y Cuestionarios , Adulto , Calibración , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Inducción de Remisión , Estudios Retrospectivos
3.
Epilepsy Behav ; 56: 149-52, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26878459

RESUMEN

Management of psychogenic nonepileptic seizures (PNES) is complex, requiring multidisciplinary care. A standardized assessment and formulation approach to PNES is lacking, yet use of a comprehensive model may alleviate problems such as mental health aftercare noncompliance. Although a biopsychosocial (BPS) approach to PNES balancing predisposing, precipitating, and perpetuating (PPP) variables has been described and has been recently tested in pilot form, it is unclear how this assessment style is perceived among community mental health practitioners such as psychotherapists (including psychologists, counselors, and social workers). We predicted preference of a comprehensive "BPS/PPP" assessment style by those most involved in PNES care (i.e., community psychotherapists). One hundred and forty-three community-based social workers and counselors completed a survey featuring a fictional PNES case followed by assessment style options ("Multiaxial," "Narrative," and "BPS/PPP"). Respondents clearly preferred the robust BPS/PPP approach over less-comprehensive multiaxial and narrative assessments (p<0.0001). Reasons for choosing the BPS/PPP by respondents include ease of organization, clear therapeutic goals, and comprehensive nature. This assessment of acceptability of a BPS/PPP approach to PNES assessment among community mental health practitioners may provide a patient-centered mechanism to enhance referrals from the neurological to mental health setting. Implications and future directions are explored.


Asunto(s)
Actitud del Personal de Salud , Salud Mental , Psicoterapia/métodos , Convulsiones/diagnóstico , Convulsiones/psicología , Encuestas y Cuestionarios , Humanos , Psicología , Convulsiones/terapia
4.
Med Care ; 53(4): 374-9, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25769057

RESUMEN

BACKGROUND: Recently, van Walraven developed a weighted summary score (VW) based on the 30 comorbidities from the Elixhauser comorbidity system. One of the 30 comorbidities, cardiac arrhythmia, is currently excluded as a comorbidity indicator in administrative datasets such as the Nationwide Inpatient Sample (NIS), prompting us to examine the validity of the VW score and its use in the NIS. METHODS: Using data from the 2009 Maryland State Inpatient Database, we derived weighted summary scores to predict in-hospital mortality based on the full (30) and reduced (29) set of comorbidities and compared model performance of these and other comorbidity summaries in 2009 NIS data. RESULTS: Weights of our derived scores were not sensitive to the exclusion of cardiac arrhythmia. When applied to NIS data, models containing derived summary scores performed nearly identically (c statistics for 30 and 29 variable-derived summary scores: 0.804 and 0.802, respectively) to the model using all 29 comorbidity indicators (c=0.809), and slightly better than the VW score (c=0.793). Each of these models performed substantially better than those based on a simple count of Elixhauser comorbidities (c=0.745) or a categorized count (0, 1, 2, or ≥ 3 comorbidities; c=0.737). CONCLUSIONS: The VW score and our derived scores are valid in the NIS and are statistically superior to summaries using simple comorbidity counts. Researchers wishing to summarize the Elixhauser comorbidities with a single value should use the VW score or those derived in this study.


Asunto(s)
Comorbilidad , Indicadores de Salud , Mortalidad Hospitalaria , Humanos , Pacientes Internos , Maryland
5.
Epilepsy Behav ; 37: 215-20, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25064739

RESUMEN

OBJECTIVE: This study aimed to assess the accuracy and operating characteristics of the Patient Health Questionnaire-9 (PHQ-9) for depression screening in adults with epilepsy. METHODS: Tertiary epilepsy center patients served as the study population, with 237 agreeing to structured interview using the Mini-International Neuropsychiatric Interview (MINI), a "gold standard" instrument developed for rapid diagnosis of neuropsychiatric disorders, including major depressive disorder (MDD); 172 also completed the PHQ-9, and 127 completed both the PHQ-9 and the Neurological Disorders Depression Inventory for Epilepsy (NDDI-E) within two days of the MINI. Sensitivity, specificity, positive and negative predictive values, and areas under the ROC curves for each instrument were determined. Cut-points of 10 for the PHQ-9 and 15 for the NDDI-E were used, and ratings at or above the cut-points were considered screen-positive. The PHQ-9 was divided into cognitive/affective (PHQ-9/CA) and somatic (PHQ-9/S) subscales to determine comparative depression screening accuracy. RESULTS: The calculated areas under the ROC curves for the PHQ-9 (n=172) and the PHQ-9/CA and PHQ-9/S subscales were 0.914, 0.924, and 0.846, respectively, with the PHQ-9 more accurate than the PHQ-9/S (p=0.002) but not different from the PHQ-9/CA (p=0.378). At cut-points of 10 and 15, respectively, the PHQ-9 had higher sensitivity (0.92 vs 0.87) but lower specificity (0.74 vs 0.89) compared with the NDDI-E. The areas under the ROC curves of the PHQ-9 and the NDDI-E showed similar accuracy (n=127; 0.930 vs 0.934; p=0.864). SIGNIFICANCE: The PHQ-9 is an efficient and nonproprietary depression screening instrument with excellent accuracy validated for use in adult patients with epilepsy as well as multiple other medical populations.


Asunto(s)
Depresión/diagnóstico , Depresión/psicología , Epilepsia/psicología , Encuestas y Cuestionarios , Adolescente , Adulto , Anciano , Trastornos del Conocimiento/etiología , Trastornos del Conocimiento/psicología , Depresión/complicaciones , Epilepsia/complicaciones , Femenino , Humanos , Entrevista Psicológica , Masculino , Persona de Mediana Edad , Trastornos del Humor/etiología , Trastornos del Humor/psicología , Enfermedades del Sistema Nervioso/complicaciones , Enfermedades del Sistema Nervioso/psicología , Pruebas Neuropsicológicas , Estándares de Referencia , Reproducibilidad de los Resultados , Medición de Riesgo , Suicidio/psicología , Adulto Joven
6.
Neurol Clin Pract ; 9(1): 32-40, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30859005

RESUMEN

BACKGROUND: We describe patient-reported outcomes (PROs) in adults with CNS tumors and evaluate their correlation with physician-reported functional status. METHODS: We completed a retrospective cohort study of patients managed at a high-volume CNS tumor institute between September 2013 and September 2014. PROs were measured using 6 domains from the PROs Measurement Information System (PROMIS): anxiety, physical function, pain interference, sleep disturbance, fatigue, and satisfaction with social roles. Physician-reported outcomes were measured using the Eastern Cooperative Oncology Group Scale of Performance Status (ECOG). We compared differences in PROMIS scores across tumor types using analysis of variance and measured the correlation between PROMIS scores and ECOG scores using spearman correlations. Finally, we compared the range of PROMIS physical function scores within each ECOG level. RESULTS: In a cohort of 2,828 patients, 1,284 (45.4%) completed all 6 PROMIS domains. There were significant differences in PROMIS scores across tumor types for all domains except anxiety. The strength of the correlation between PROMIS and ECOG scores was weak to moderate for all PROMIS domains (all p < 0.001). The correlation was the strongest between the physical function domain and ECOG score (ρ = -0.54), although there was a broad distribution of physical function scores within ECOG level, with scores spanning nearly 5 SDs within most ECOG levels. CONCLUSIONS: Symptom burden was associated with tumor type. There were only weak to moderate correlations between PROMIS and ECOG scores, underscoring the importance of integrating PROs into clinical practice for patients with CNS tumors.

7.
PM R ; 10(2): 160-167, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28694220

RESUMEN

BACKGROUND: Reducing the incidence of indwelling urinary catheter (IUC) use and early removal of the devices that are inserted are appropriate priorities for quality patient care. Just like symptomatic bacteriuria, failed catheter removal as a complication of IUC use is associated with considerable morbidity. In the ideal setting, patients who need IUCs have them, and patients who do not need them will have them removed safely, with the goal of reducing medical complications and facilitating the rehabilitation phase of care. OBJECTIVE: To determine the incidence of failed removal of IUCs and the factors associated with failed removal in persons hospitalized with acute stroke. DESIGN: Retrospective review of medical records and associated clinical data collection platforms. SETTING: Comprehensive stroke center at a tertiary care hospital. PATIENTS: The study cohort included 175 stroke patients admitted to the hospital and managed with IUCs. Mean age was 66.1 years (standard deviation = 15), 55% were female. METHODS: Univariable and multiple logistic regression analyses were performed. Variables assessed included age, gender, race, duration of hospital stay, stroke subtype, National Institutes of Health Stroke Scale, and 6-Clicks Scale, which is a measure of functional status. MAIN OUTCOME MEASUREMENTS: The dependent variable was occurrence of a failed attempt at removal of an IUC, defined as removal followed by a catheter reinsertion. RESULTS: During the study period, 175 of 432 patients with acute hospital admission for new stroke had an IUC removal event. Of these patients, 46 (26%) experienced a failed catheter removal. On univariate analysis, factors significantly associated with failed removal included presence of a hemorrhagic stroke (P = .005), lower level of physical function (by 6-Clicks and NIHSS scores), hospital length of stay (P < .001), and discharge location (P = .005). Bedside bladder ultrasound testing by nursing staff was used more frequently in the group of patients who had unsuccessful IUC removals (95% confidence interval 4.56-21.67, P < .001). Length of stay (P < .001), white race (P = .001), and hemorrhagic stroke (P = .009) were associated independently with failed catheter removal after adjustment for other clinical variables. CONCLUSIONS: This single-site study identified a high incidence of failed urinary catheter removal in patients with stroke, along with factors associated with failed removal. This is the first step in developing a predictive model that could reduce the incidence of this adverse event. Policies, penalties, and protocols designed to reduce catheter days must be sensitive to the special situations in which IUCs are medically necessary and equal consideration given to identifying the patients for which catheter removal poses a greater risk than continued catheter use. LEVEL OF EVIDENCE: III.


Asunto(s)
Catéteres de Permanencia/efectos adversos , Remoción de Dispositivos/efectos adversos , Medición de Riesgo/métodos , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular/terapia , Catéteres Urinarios/efectos adversos , Infecciones Urinarias/epidemiología , Anciano , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Ohio/epidemiología , Estudios Retrospectivos , Factores de Riesgo , Insuficiencia del Tratamiento , Infecciones Urinarias/etiología
8.
Int J MS Care ; 19(4): 199-207, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28835744

RESUMEN

BACKGROUND: Patients with multiple sclerosis (MS) newly seen by a neurologist may benefit from early psychological intervention owing to the reciprocal relationship between stress and disease progression. However, it is uncertain what factors contribute to patients' receiving these services. METHODS: Logistic regression analysis of prospectively gathered data evaluated how demographic and disease characteristics and emotional/physical health factors contributed to referral to receive behavioral medicine (BM) services within 1 year of their first neurology appointment at the Mellen Center for Multiple Sclerosis at the Cleveland Clinic. Survival analyses then evaluated whether this resulted in earlier receipt of services. RESULTS: Although many factors were associated with receiving BM services during univariate analyses (age, race, marital status, years since MS onset, depression, stress, and quality of life), when considering multivariable interactions, only two variables remained significant: age (odds ratio [OR] = 0.86, 95% confidence interval [CI], 0.80-0.92) and depression (OR = 1.56, 95% CI, 1.39-1.75). Survival analyses did not show differences in time to BM services for stratifications of age or depression scores. CONCLUSIONS: Younger patients and patients with more severe depression were more likely to receive BM services within 1 year of their first neurology appointment. Future research will focus on evaluating whether these are also the patients in greatest need of services or whether they are simply more open to receiving them.

9.
Pain ; 158(7): 1380-1394, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28328578

RESUMEN

Increased prescribing of opioids for chronic noncancer pain is associated with significant social costs, including overdose and addiction. In this context, there is interest in interdisciplinary chronic pain rehabilitation programs focusing on self-management and minimizing opioid use. This study examined outcomes of patients weaned from opioids in an ICPRP from 2007 to 2012. Participants included 413 patients on high dose chronic opioid therapy (COT; >100 mg), 528 on low dose COT, and 516 not on opioids (NO). Outcomes were assessed at discharge, 6, and 12 months posttreatment through self-report and chart review. One thousand one hundred ninety-four participants completed treatment (81.95%); 86.74% of those on opioids were weaned. High doses were less likely to complete (78.45%) than NO participants (85.27%; P < 0.05). Results showed immediate (P < 0.01) and sustained improvements (P < 0.05) in pain severity, depression, anxiety, and functional impairment with no group differences. Effect sizes ranged from medium to large (Cohen d values 0.57-1.96). Longitudinal medication use data were available for 319 no dose and 417 weaned participants; opioid resumption rates were 10.51% and 30.70% respectively. There were no differences in resumption between the high dose and low dose groups. Logistic regression analyses determined that opioid dose predicted neither treatment completion nor opioid resumption. Anxiety predicted completion, and functional impairment predicted opioid resumption within 1 year of discharge. Results suggest that patients on COT can be successfully weaned with long-term benefits in pain, mood, and function. Targeting anxiety and functional restoration may increase success rates.


Asunto(s)
Afecto/efectos de los fármacos , Analgésicos Opioides/uso terapéutico , Dolor Crónico/tratamiento farmacológico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Analgésicos Opioides/administración & dosificación , Ansiedad/diagnóstico , Dolor Crónico/diagnóstico , Depresión/diagnóstico , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Persona de Mediana Edad , Manejo del Dolor/métodos , Dimensión del Dolor , Autoinforme , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Adulto Joven
10.
Neurology ; 86(19): 1801-7, 2016 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-27164715

RESUMEN

OBJECTIVE: To evaluate the performance of the Patient Reported Outcomes Measurement Information System (PROMIS) physical function (PF) scale compared to the validated Stroke Impact Scale-16 (SIS-16) in ischemic stroke patients seen in an ambulatory cerebrovascular clinic. METHODS: This was a retrospective cohort study. PROMIS PF (computer adaptive testing version) and SIS-16 measures were electronically collected on 1,946 ischemic stroke patients seen in a cerebrovascular clinic using an electronic platform from September 12, 2012, to June 16, 2015. Distribution of scores was compared to assess ceiling and floor effects. Correlations with other commonly used functional status scales were performed to assess convergent validity. RESULTS: The SIS-16 and PROMIS PF had a 19.6% and <1% ceiling effect, respectively. Patients completed 16 SIS-16 items and a median of 4 (interquartile range 4-4) PROMIS PF items. Internal consistency of both SIS-16 and PROMIS PF was excellent. The SIS-16 had slightly but significantly higher correlations with the other functional scales than PROMIS PF. CONCLUSIONS: The use of PROMIS to obtain electronic patient-reported functional status in an ambulatory setting is feasible. PROMIS PF is an option for measurement of physical function in ischemic stroke patients. It had similar test characteristics as the SIS-16 but with lower patient burden and minimal ceiling effect.


Asunto(s)
Isquemia Encefálica/diagnóstico , Diagnóstico por Computador/métodos , Medición de Resultados Informados por el Paciente , Índice de Severidad de la Enfermedad , Accidente Cerebrovascular/diagnóstico , Isquemia Encefálica/fisiopatología , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Autoinforme , Accidente Cerebrovascular/fisiopatología
11.
Circ Cardiovasc Qual Outcomes ; 8(6 Suppl 3): S179-89, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26515207

RESUMEN

We describe the development, implementation, and outcomes of the first 2 years of the Electronic Stroke CarePath, an initiative developed for management of ischemic stroke patients in an effort to improve efficiency and quality of care for patients. The CarePath consists of care pathways for ischemic stroke that are integrated within the electronic health record. Patient-reported outcomes are collected using an external software platform. Documentation tools, order sets, and clinical decision support were designed to improve efficiency, optimize process measure adherence, and produce clinical data as a byproduct of care that are available for future analyses. Inpatient mortality and length of stay were compared before and after CarePath implementation in ischemic stroke patients after adjustment for case-mix. Postdischarge functional outcomes of patients with ischemic stroke were compared between the first 3 months of rollout and remainder of the study period. From January 2011 to December 2012, there were 1106 patients with ischemic stroke on the CarePath. There was a decline in inpatient mortality in patients with ischemic stroke, but not in control patients with intracerebral or subarachnoid hemorrhage. Completion rate of patient-reported questionnaires at postdischarge stroke follow-up was 72.9%. There was a trend toward improved functional outcomes at follow-up with CarePath implementation. Implementation of the Electronic Stroke CarePath is feasible and may be associated with a benefit in multiple different outcomes after ischemic stroke. This approach may be an important strategy for optimizing stroke care in the future.


Asunto(s)
Isquemia Encefálica/terapia , Registros Electrónicos de Salud , Accidente Cerebrovascular/terapia , Anciano , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/mortalidad , Manejo de la Enfermedad , Femenino , Estudios de Seguimiento , Adhesión a Directriz , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Evaluación de Procesos y Resultados en Atención de Salud , Mejoramiento de la Calidad , Recuperación de la Función , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/mortalidad , Análisis de Supervivencia , Resultado del Tratamiento
12.
EGEMS (Wash DC) ; 3(1): 1125, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26290882

RESUMEN

INTRODUCTION: The use of clinically derived data from electronic health records (EHRs) and other electronic clinical systems can greatly facilitate clinical research as well as operational and quality initiatives. One approach for making these data available is to incorporate data from different sources into a joint data warehouse. When using such a data warehouse, it is important to understand the quality of the data. The primary objective of this study was to determine the completeness and concordance of common types of clinical data available in the Knowledge Program (KP) joint data warehouse, which contains feeds from several electronic systems including the EHR. METHODS: A manual review was performed of specific data elements for 250 patients from an EHR, and these were compared with corresponding elements in the KP data warehouse. Completeness and concordance were calculated for five categories of data including demographics, vital signs, laboratory results, diagnoses, and medications. RESULTS: In general, data elements for demographics, vital signs, diagnoses, and laboratory results were present in more cases in the source EHR compared to the KP. When data elements were available in both sources, there was a high concordance. In contrast, the KP data warehouse documented a higher prevalence of deaths and medications compared to the EHR. DISCUSSION: Several factors contributed to the discrepancies between data in the KP and the EHR-including the start date and frequency of data feeds updates into the KP, inability to transfer data located in nonstructured formats (e.g., free text or scanned documents), as well as incomplete and missing data variables in the source EHR. CONCLUSION: When evaluating the quality of a data warehouse with multiple data sources, assessing completeness and concordance between data set and source data may be better than designating one to be a gold standard. This will allow the user to optimize the method and timing of data transfer in order to capture data with better accuracy.

13.
Plant Cell ; 20(4): 995-1011, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18424615

RESUMEN

During polarized growth and tissue morphogenesis, cells must reorganize their cytoplasm and change shape in response to growth signals. Dynamic polymerization of actin filaments is one cellular component of polarized growth, and the actin-related protein 2/3 (ARP2/3) complex is an important actin filament nucleator in plants. ARP2/3 alone is inactive, and the Arabidopsis thaliana WAVE complex translates Rho-family small GTPase signals into an ARP2/3 activation response. The SCAR subunit of the WAVE complex is the primary activator of ARP2/3, and plant and vertebrate SCARs are encoded by a small gene family. However, it is unclear if SCAR isoforms function interchangeably or if they have unique properties that customize WAVE complex functions. We used the Arabidopsis distorted group mutants and an integrated analysis of SCAR gene and protein functions to address this question directly. Genetic results indicate that each of the four SCARs functions in the context of the WAVE-ARP2/3 pathway and together they define the lone mechanism for ARP2/3 activation. Genetic interactions among the scar mutants and transgene complementation studies show that the activators function interchangeably to meet the threshold for ARP2/3 activation in the cell. Interestingly, double, triple, and quadruple mutant analyses indicate that individual SCAR genes vary in their relative importance depending on the cell type, tissue, or organ that is analyzed. Differences among SCARs in mRNA levels and the biochemical efficiency of ARP2/3 activation may explain the functional contributions of individual genes.


Asunto(s)
Proteína 2 Relacionada con la Actina/fisiología , Proteína 3 Relacionada con la Actina/fisiología , Arabidopsis/fisiología , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Secuencia de Bases , Cartilla de ADN , Evolución Molecular , Expresión Génica , Genes de Plantas , Datos de Secuencia Molecular , Morfogénesis , Filogenia , Brotes de la Planta/crecimiento & desarrollo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
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