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1.
Cerebellum ; 21(6): 879-904, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34665396

RESUMEN

Purkinje cells (PCs) in the cerebellar flocculus carry rate-coded information that ultimately drives eye movement. Floccular PCs lying nearby each other exhibit partial synchrony of their simple spikes (SS). Elsewhere in the cerebellum, PC SS synchrony has been demonstrated to influence activity of the PCs' synaptic targets, and some suggest it constitutes another vector for information transfer. We investigated in the cerebellar flocculus the extent to which the rate code and PC synchrony interact. One motivation for the study was to explain the cerebellar deficits in ataxic mice like tottering; we speculated that PC synchrony has a positive effect on rate code transmission that is lost in the mutants. Working in transgenic mice whose PCs express channelrhodopsin, we exploited a property of optogenetics to control PC synchrony: pulsed photostimulation engenders stimulus-locked spiking, whereas continuous photostimulation engenders spiking whose timing is unconstrained. We photoactivated flocculus PCs using pulsed stimuli with sinusoidally varying timing vs. continuous stimuli with sinusoidally varying intensity. Recordings of PC pairs confirmed that pulsed stimuli engendered greater PC synchrony. We quantified the efficiency of transmission of the evoked PC firing rate modulation from the amplitudes of firing rate modulation and eye movement. Rate code transmission was slightly poorer in the conditions that generated greater PC synchrony, arguing against our motivating speculation regarding the origin of ataxia in tottering. Floccular optogenetic stimulation prominently augmented a 250-300 Hz local field potential oscillation, and we demonstrate relationships between the oscillation power and the evoked PC synchrony.


Asunto(s)
Vermis Cerebeloso , Células de Purkinje , Ratones , Animales , Células de Purkinje/fisiología , Channelrhodopsins , Cerebelo/fisiología , Movimientos Oculares , Ataxia , Potenciales de Acción
2.
J Nerv Ment Dis ; 210(5): 373-379, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-34937847

RESUMEN

ABSTRACT: To ascertain the relative importance of attributes considered when deciding to discharge patients hospitalized with major depressive disorder (MDD) and active suicidal ideation with intent, a choice-based conjoint analysis was conducted via online survey among US-based psychiatrists actively managing such patients. Potential attributes and attribute levels were identified. Attribute importance in decision to discharge and the discharge time frame were assessed. One hundred psychiatrists completed the survey. The relative importance of attributes were current MDD severity (relative importance weight [out of 100] 24.8 [95% confidence interval, 23.3-26.3]), clinician assessment of current suicidal ideation (20.8 [18.5-23.0]), previous history of suicide attempts (16.7 [15.9-17.6]), psychosocial support at discharge (13.0 [11.7-14.4]), postdischarge outpatient follow-up (9.8 [8.8-10.8]), current length of hospital stay (9.2 [8.1-10.3]), and suicidal ideation at admission (5.7 [4.8-6.6]). Thus, current clinical symptoms were considered the most important attributes by psychiatrists when discharging patients initially hospitalized with MDD and active suicidal ideation with intent.


Asunto(s)
Trastorno Depresivo Mayor , Psiquiatría , Adulto , Cuidados Posteriores , Trastorno Depresivo Mayor/psicología , Trastorno Depresivo Mayor/terapia , Humanos , Alta del Paciente , Ideación Suicida
3.
J Natl Compr Canc Netw ; 20(4): 371-377.e5, 2021 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-34384045

RESUMEN

BACKGROUND: Optimal treatment of nonoperative patients with large, node-negative non-small cell lung cancer (NSCLC) is poorly defined. Current NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) recommend definitive radiotherapy (RT) with or without sequential chemotherapy and do not include concurrent chemoradiotherapy (chemoRT) as a treatment option. In this study, we identified factors that predict nonadherence to NCCN Guidelines. PATIENTS AND METHODS: Patients who received definitive RT for nonmetastatic, node-negative NSCLC with tumor size of 5 to 7 cm were identified in the National Cancer Database from 2004 through 2016. Patients were evaluated by RT type (stereotactic body RT [SBRT], hypofractionated RT [HFRT], or conventionally fractionated RT [CFRT]) and chemotherapy use (none, sequential, or concurrent with RT). Patients were classified as receiving NCCN-adherent (RT with or without sequential chemotherapy) or NCCN-nonadherent (concurrent chemoRT) treatment. Demographic and clinical factors were assessed with logistic regression modeling. Overall survival was evaluated with Kaplan-Meier, log-rank, and univariable/multivariable Cox proportional hazards regression analyses. RESULTS: Among 2,020 patients in our cohort, 32% received NCCN-nonadherent concurrent chemoRT, whereas others received NCCN-adherent RT alone (51%) or sequential RT and chemotherapy (17%). CFRT was most widely used (64% CFRT vs 22% SBRT vs 14% HFRT). Multivariable analysis revealed multiple factors to be associated with NCCN-nonadherent chemoRT: age ≤70 versus >70 years (odds ratio [OR] , 2.72; P<.001), treatment at a nonacademic facility (OR, 1.65; P<.001), and tumor size 6 to 7 cm versus 5 to 6 cm (OR, 1.27; P=.026). Survival was similar between the NCCN-nonadherent chemoRT and NCCN-adherent groups (hazard ratio, 1.00; P=.992) in multivariable analysis. CONCLUSIONS: A substantial proportion of inoperable patients with large, node-negative NSCLC are not treated according to NCCN Guidelines and receive concurrent chemoRT. Younger patients with larger tumors receiving treatment at nonacademic medical centers were more likely to receive NCCN-nonadherent therapy, but adherence to NCCN Guidelines was not associated with differences in overall survival.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Radiocirugia , Anciano , Quimioradioterapia , Humanos , Neoplasias Pulmonares/patología , Hipofraccionamiento de la Dosis de Radiación , Resultado del Tratamiento
4.
Support Care Cancer ; 27(4): 1425-1433, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30187220

RESUMEN

BACKGROUND: Vaginal dilators (VD) are recommended following vaginal or pelvic radiotherapy for patients with endometrial carcinoma (EC) to prevent vaginal stenosis (VS). The time course of VS is not fully understood and the optimal duration of VD use is unknown. METHODS: We reviewed 243 stage IA-II EC patients who received adjuvant brachytherapy (BT) at an academic tertiary referral center. Patients were instructed to use their VD three times per week for at least 1-year duration. The primary outcome was development of grade ≥ 1 VS using CTCAEv4 criteria during the follow-up period. The log-rank test and multivariable Cox proportional hazards modeling were used to evaluate the effect of VD use (noncompliance vs. standard compliance [up to 1 year] vs. extended compliance [over 1 year]) on VS. RESULTS: The median follow-up was 15.2 months over the 5-year study period. At 15 months, the incidence of VS was 38.8% for noncompliant patients, 33.5% for those with standard compliance, and 21.4% for those with extended compliance (median time to grade ≥ 1 VS was 17.5 months, 26.7 months, and not yet reached for these groups, respectively). On multivariable Cox regression analysis, extended compliance remained a significant predictor of reduced VS risk when compared to both noncompliance (HR 0.38, 95% CI 0.18-0.80, p = 0.012) and standard compliance (HR 0.43, 95% CI 0.20-0.89, p = 0.023). CONCLUSIONS: The risk of VS persists beyond 1 year after BT. Extended VD compliance beyond 1 year may mitigate this risk.


Asunto(s)
Braquiterapia , Constricción Patológica/prevención & control , Dilatación/instrumentación , Neoplasias Endometriales/radioterapia , Enfermedades Vaginales/prevención & control , Adulto , Anciano , Braquiterapia/efectos adversos , Constricción Patológica/etiología , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Cooperación del Paciente , Dosificación Radioterapéutica , Resultado del Tratamiento , Vagina/patología , Vagina/efectos de la radiación
5.
Cancer ; 123(14): 2762-2772, 2017 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-28323338

RESUMEN

BACKGROUND: Extranodal (or extracapsular) extension (ENE) is an adverse prognostic factor in patients with head and neck cancers who undergo primary surgery. However, the significance of ENE in human papillomavirus (HPV)-positive oropharyngeal squamous cell carcinoma (OPSCC) is not well established, and single-institution studies have not established that ENE predicts inferior outcome. The authors investigated the prognostic value of ENE in HPV-positive patients who underwent primary surgery and whether adjuvant chemoradiation improved overall survival (OS) compared with radiation alone in ENE-positive patients. METHODS: Patients who underwent primary surgery for pathologic T1 (pT1) through pT4 tumors, pathologic N1 (pN1) through pN3 lymph node status, HPV-positive OPSCC were identified in the National Cancer Data Base from 2010 through 2012. Features associated with ENE were analyzed. Univariable and multivariable Cox regression analyses identified predictors of OS. The effect of adjuvant treatment on OS in ENE-positive cohort was also evaluated. RESULTS: In total, 1043 patients met inclusion criteria, among whom 43.5% were ENE-positive. Of the ENE-positive patients who had treatment details available, 72% received concurrent chemoradiotherapy, 16% received radiotherapy, and 12% received no adjuvant treatment. After a median follow-up of 28.4 months, ENE was associated with worse 3-year OS (89.3% vs 93.6%; P = .01). On multivariable analysis that included involved lymph nodes, only ENE, lymphovascular invasion, pT3/pT4 tumors, and Charlson-Deyo score were associated with worse OS. Among ENE-positive patients, there was no difference in 3-year OS between those who received adjuvant concurrent chemoradiotherapy versus radiotherapy alone (89.6% vs 89.3%, respectively; P = .55). Propensity score-matched comparison revealed similar results. CONCLUSIONS: ENE is associated with inferior OS in patients with HPV-positive OPSCC. However, OS was not better with adjuvant chemoradiotherapy compared with radiotherapy alone in ENE-positive patients. The current findings support the need for prospective studies of adjuvant chemoradiation in HPV-positive patients with ENE. Cancer 2017;123:2762-72. © 2017 American Cancer Society.


Asunto(s)
Carcinoma de Células Escamosas/patología , Neoplasias de Cabeza y Cuello/patología , Neoplasias Orofaríngeas/patología , Infecciones por Papillomavirus/patología , Carcinoma de Células Escamosas/cirugía , Carcinoma de Células Escamosas/virología , Quimioradioterapia Adyuvante , Femenino , Neoplasias de Cabeza y Cuello/cirugía , Neoplasias de Cabeza y Cuello/virología , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Invasividad Neoplásica , Estadificación de Neoplasias , Neoplasias Orofaríngeas/cirugía , Neoplasias Orofaríngeas/virología , Procedimientos Quirúrgicos Otorrinolaringológicos , Papillomaviridae , Pronóstico , Puntaje de Propensión , Modelos de Riesgos Proporcionales , Radioterapia Adyuvante , Estudios Retrospectivos , Carcinoma de Células Escamosas de Cabeza y Cuello , Tasa de Supervivencia
6.
Cancer ; 123(4): 688-696, 2017 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-27741355

RESUMEN

BACKGROUND: Stereotactic body radiotherapy (SBRT) is the standard of care for patients with nonoperative, early-stage non-small cell lung cancer (NSCLC) measuring < 5 cm, but its use among patients with tumors measuring ≥5 cm is considerably less defined, with the existing literature limited to small, single-institution reports. The current multi-institutional study reported outcomes evaluating the largest such population reported to date. METHODS: Clinical/treatment characteristics, outcomes, toxicities, and patterns of failure were assessed in patients with primary NSCLC measuring ≥5 cm without evidence of distant/lymph node metastasis who underwent SBRT using ≤5 fractions. Statistics included Kaplan-Meier survival analyses and univariate/multivariate Cox proportional hazards models. RESULTS: A total of 92 patients treated from 2004 through 2016 were analyzed from 12 institutions. The median follow-up was 12 months (15 months in survivors). The median age and tumor size among the patients were 73 years (range, 50-95 years) and 5.4 cm (range, 5.0-7.5 cm), respectively. The median dose/fractionation was 50 Gray/5 fractions. The actuarial local control rates at 1 year and 2 years were 95.7% and 73.2%, respectively. The disease-free survival rate was 72.1% and 53.5%, respectively, at 1 year and 2 years. The 1-year and 2-year disease-specific survival rates were 95.5% and 78.6%, respectively. The median, 1-year, and 2-year overall survival rates were 21.4 months, 76.2%, and 46.4%, respectively. On multivariate analysis, lung cancer history and pre-SBRT positron emission tomography maximum standardized uptake value were found to be associated with overall survival. Posttreatment failures were most commonly distant (33% of all disease recurrences), followed by local (26%) and those occurring elsewhere in the lung (23%). Three patients had isolated local failures. Grade 3 to 4 toxicities included 1 case (1%) and 4 cases (4%) of grade 3 dermatitis and radiation pneumonitis, respectively (toxicities were graded according to the Common Terminology Criteria for Adverse Events [version 4.0]). Grades 2 to 5 radiation pneumonitis occurred in 11% of patients. One patient with a tumor measuring 7.5 cm and a smoking history of 150 pack-years died of radiation pneumonitis. CONCLUSIONS: The results of the current study, which is the largest study of patients with NSCLC measuring ≥5 cm reported to date, indicate that SBRT is a safe and efficacious option. Cancer 2017;123:688-696. © 2016 American Cancer Society.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Recurrencia Local de Neoplasia/radioterapia , Radiocirugia , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/epidemiología , Carcinoma de Pulmón de Células no Pequeñas/patología , Supervivencia sin Enfermedad , Fraccionamiento de la Dosis de Radiación , Femenino , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Metástasis Linfática , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/epidemiología , Recurrencia Local de Neoplasia/patología , Resultado del Tratamiento
7.
J Natl Compr Canc Netw ; 15(3): 355-362, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28275036

RESUMEN

Background: Definitive chemoradiotherapy (CRT) is recommended by the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Anal Carcinoma for all patients with stage I anal canal cancer. Because these patients were not well represented in clinical trials establishing CRT as standard therapy, it is unclear whether NCCN recommendations are being closely followed for stage I disease. This study identified factors that predict for NCCN Guideline-concordant versus NCCN Guideline-discordant care. Methods: Using the National Cancer Data Base, we identified patients diagnosed with anal canal carcinoma from 2004 to 2012 who received concurrent CRT (radiotherapy [RT] 45.0-59.4 Gy with multiagent chemotherapy), RT alone (45.0-59.4 Gy), or surgical procedure alone (local tumor destruction, tumor excision, or abdominoperineal resection). Demographic and clinicopathologic factors were analyzed using the chi-square test and logistic regression modeling. Results: A total of 1,082 patients with histologically confirmed stage I anal cancer were identified, among whom 665 (61.5%) received CRT, 52 (4.8%) received RT alone, and 365 (33.7%) received only a surgical procedure. Primary analyses were restricted to patients receiving CRT or excision alone, as these were most common. Multivariable analysis identified factors independently associated with reduced odds of CRT receipt: low versus intermediate/high tumor grade (adjusted odds ratio [AOR], 0.21; 95% CI, 0.14-0.29; P<.001), tumor size <1 cm vs 1 to 2 cm (AOR, 0.24; 95% CI, 0.17-0.35; P<.001), age ≥70 versus 50 to 69 years (AOR, 0.36; 95% CI, 0.24-0.54; P<.001), male sex (AOR, 0.63; 95% CI, 0.45-0.90; P=.009), and treatment at an academic versus a non-academic facility (AOR, 0.58; 95% CI, 0.41-0.81; P=.002). Conclusions: Despite the NCCN recommendation of CRT for stage I anal cancer, at least one-third of patients appear to be receiving guideline-discordant management. Excision alone is more common for patients who are elderly, are male, have small or low-grade tumors, or were evaluated at academic facilities.


Asunto(s)
Neoplasias del Ano/diagnóstico , Neoplasias del Ano/terapia , Cumplimiento de la Medicación , Guías de Práctica Clínica como Asunto , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias del Ano/mortalidad , Terapia Combinada , Bases de Datos Factuales , Manejo de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Oportunidad Relativa , Pronóstico , Modelos de Riesgos Proporcionales , Factores de Riesgo , Resultado del Tratamiento
8.
J Neurophysiol ; 114(3): 1455-67, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26108953

RESUMEN

Rigorous descriptions of ocular motor mechanics are often needed for models of ocular motor circuits. The mouse has become an important tool for ocular motor studies, yet most mechanical data come from larger species. Recordings of mouse abducens neurons indicate the mouse mechanics share basic viscoelastic properties with larger species but have considerably longer time constants. Time constants can also be extracted from the rate at which the eye re-centers when released from an eccentric position. The displacement can be accomplished by electrically stimulating ocular motor nuclei, but electrical stimulation may also activate nearby ocular motor circuitry. We achieved specific activation of abducens motoneurons through photostimulation in transgenic mice expressing channelrhodopsin in cholinergic neurons. Histology confirmed strong channelrhodopsin expression in the abducens nucleus with relatively little expression in nearby ocular motor structures. Stimulation was delivered as 20- to 1,000-ms pulses and 40-Hz trains. Relaxations were modeled best by a two-element viscoelastic system. Time constants were sensitive to stimulus duration. Analysis of isometric relaxation of isolated mouse extraocular muscles suggest the dependence is attributable to noninstantaneous decay of active forces in non-twitch fibers following stimulus offset. Time constants were several times longer than those obtained in primates, confirming that the mouse ocular motor mechanics are relatively sluggish. Finally, we explored the effects of 0.1- to 20-Hz sinusoidal photostimuli and demonstrated their potential usefulness in characterizing ocular motor mechanics, although this application will require further data on the temporal relationship between photostimulation and neuronal firing in extraocular motoneurons.


Asunto(s)
Nervio Abducens/fisiología , Movimientos Oculares , Neuronas Motoras/fisiología , Rodopsina/genética , Animales , Neuronas Colinérgicas/metabolismo , Neuronas Colinérgicas/fisiología , Ratones , Neuronas Motoras/metabolismo , Contracción Muscular , Optogenética , Rodopsina/metabolismo
9.
J Neurophysiol ; 112(10): 2647-63, 2014 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-25143538

RESUMEN

Mutation of the Cacna1a gene for the P/Q (CaV2.1) calcium channel invariably leads to cerebellar dysfunction. The dysfunction has been attributed to disrupted rhythmicity of cerebellar Purkinje cells, but the hypothesis remains unproven. If irregular firing rates cause cerebellar dysfunction, then the irregularity and behavioral deficits should covary in a series of mutant strains of escalating severity. We compared firing irregularity in floccular and anterior vermis Purkinje cells in the mildly affected rocker and moderately affected tottering Cacna1a mutants and normal C57BL/6 mice. We also measured the amplitude and timing of modulations of floccular Purkinje cell firing rate during the horizontal vestibuloocular reflex (VOR, 0.25-1 Hz) and the horizontal and vertical optokinetic reflex (OKR, 0.125-1 Hz). We recorded Purkinje cells selective for rotational stimulation about the vertical axis (VAPCs) and a horizontal axis (HAPCs). Irregularity scaled with behavioral deficit severity in the flocculus but failed to do so in the vermis, challenging the irregularity hypothesis. Mutant VAPCs exhibited unusually strong modulation during VOR and OKR, the response augmentation scaling with phenotypic severity. HAPCs exhibited increased OKR modulation but in tottering only. The data contradict prior claims that modulation amplitude is unaffected in tottering but support the idea that attenuated compensatory eye movements in Cacna1a mutants arise from defective transfer of Purkinje cell signals to downstream circuitry, rather than attenuated synaptic transmission within the cerebellar cortex. Shifts in the relative sizes of the VAPC and HAPC populations raise the possibility that Cacna1a mutations influence the development of floccular zone architecture.


Asunto(s)
Potenciales de Acción/fisiología , Canales de Calcio Tipo N/genética , Canales de Calcio Tipo N/metabolismo , Mutación , Células de Purkinje/fisiología , Animales , Medidas del Movimiento Ocular , Movimientos Oculares/fisiología , Ratones Endogámicos C57BL , Ratones Mutantes , Microelectrodos , Fenotipo , Estimulación Física , Reflejo Vestibuloocular/fisiología , Rotación
10.
Adv Radiat Oncol ; 8(4): 101214, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37124314

RESUMEN

Purpose: Various radiation therapy (RT) dose/fractionation schedules are acceptable for palliation in multiple myeloma. Nine years of single-institution RT experience were reviewed to determine the influence of dose/fractionation and other factors pertinent to individualizing therapy. Methods and Materials: In total, 152 items were identified from Current Procedural Terminology codes for multiple myeloma treatment from 2012 through June 30, 2021. After exclusions, 205 sites of radiation in 94 patients were reviewed. Data were captured from treatment planning and clinical records. To statistically assess the association between biological effective dose (BED10) and variables of interest, BED was first dichotomized to <24 Gy versus ≥24 Gy. Multivariate analysis used SAS software and a generalized estimating equation approach to account for multiple observations per patient. Results: Fractions of 1.8 to 8 Gy were used in 1 to 25 fractions. Most patients had no significant toxicity. Grade 1 toxicity was more likely with greater BED radiation courses, as expected (20% vs 12% for BED <24 Gy). Pain relief was complete or very good for most sites, with <3% reporting no pain relief. Eleven sites in 9 patients required retreatment. All retreatment sites had palliation that was lasting, with a median of 22 months to last follow-up or death after repeat course (range, 0.5-106 months). There was a trend for better pain control and less risk of fracture retreatment with BED ≥24 Gy. Conclusions: Most patients had good palliation without toxicity. BED ≥24 Gy caused 8% greater risk of grade 1 toxicity and trended toward better pain control plus reduced risk of fracture retreatment.

11.
Radiat Oncol ; 18(1): 57, 2023 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-36964622

RESUMEN

PURPOSE: Relating dose-volume histogram (DVH) information to patient outcomes is critical for outcomes research in radiation oncology, but this is statistically challenging. We performed this focused review of DVH toxicity studies to characterize current statistical approaches and determine the need for updated reporting recommendations. METHODS AND MATERIALS: We performed a focused MEDLINE search to identify studies published in 5 radiation oncology specialty journals that associated dosimetry with toxicity outcomes in humans receiving radiotherapy between 2015 and 2021. Elements abstracted from each manuscript included the study outcome, organs-at-risk (OARs) considered, DVH parameters analyzed, summary of the analytic approach, use of multivariable statistics, goodness-of-fit reporting, completeness of model reporting, assessment of multicollinearity, adjustment for multiple comparisons, and methods for dichotomizing variables. Each study was also assessed for sufficient reporting to allow for replication of results. RESULTS: The MEDLINE search returned 2,300 studies for review and 325 met the inclusion criteria for the analysis. DVH variables were dichotomized using cut points in 154 (47.4%) studies. Logistic regression (55.4% of studies) was the most common statistical method used to relate DVH to toxicity outcomes, followed by Cox regression (20.6%) and linear regression (12.0%). Multivariable statistical tests were performed in 226 (69.5%) studies; of these, the possibility of multicollinearity was addressed in 47.8% and model goodness-of-fit were reported in 32.6%. The threshold for statistical significance was adjusted to account for multiple comparisons in 41 of 196 (17.1%) studies that included multiple statistical comparisons. Twenty-eight (8.6%) studies were classified as missing details necessary to reproduce the study results. CONCLUSIONS: Current practices of statistical reporting in DVH outcomes suggest that studies may be vulnerable to threats against internal and external validity. Recommendations for reporting are provided herein to guard against such threats and to promote cohesiveness among radiation oncology outcomes researchers.


Asunto(s)
Exposición a la Radiación , Planificación de la Radioterapia Asistida por Computador , Humanos , Órganos en Riesgo , Radiometría , Dosis de Radiación , Dosificación Radioterapéutica
12.
J Thorac Oncol ; 18(3): 339-349, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36396062

RESUMEN

INTRODUCTION: Distant metastases (DMs) are the primary driver of mortality for patients with early stage NSCLC receiving stereotactic body radiation therapy (SBRT), yet patient-level risk is difficult to predict. We developed and validated a model to predict individualized risk of DM in this population. METHODS: We used a multi-institutional database of 1280 patients with cT1-3N0M0 NSCLC treated with SBRT from 2006 to 2015 for model development and internal validation. A Fine and Gray (FG) regression model was built to predict 1-year DM risk and compared with a random survival forests model. The higher performing model was evaluated on an external data set of 130 patients from a separate institution. Discriminatory performance was evaluated using the time-dependent area under the curve (AUC). Calibration was assessed graphically and with Brier scores. RESULTS: The FG model yielded an AUC of 0.71 (95% confidence interval [CI]: 0.57-0.86) compared with the AUC of random survival forest at 0.69 (95% CI: 0.63-0.85) in the internal test set and was selected for further testing. On external validation, the FG model yielded an AUC of 0.70 (95% CI: 0.57-0.83) with good calibration (Brier score: 0.08). The model identified a high-risk patient subgroup with greater 1-year DM rates in the internal test (20.0% [3 of 15] versus 2.9% [7 of 241], p = 0.001) and external validation (21.4% [3 of 15] versus 7.8% [9 of 116], p = 0.095). A model nomogram and online application was made available. CONCLUSIONS: We developed and externally validated a practical model that predicts DM risk in patients with NSCLC receiving SBRT which may help select patients for systemic therapy.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Radiocirugia , Humanos , Pronóstico , Neoplasias Pulmonares/patología , Carcinoma de Pulmón de Células no Pequeñas/patología , Nomogramas
13.
J Neurophysiol ; 108(9): 2509-23, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22896719

RESUMEN

The mechanics of the eyeball and orbital tissues (the "ocular motor plant") are a fundamental determinant of ocular motor signal processing. The mouse is used increasingly in ocular motor physiology, but little is known about its plant mechanics. One way to characterize the mechanics is to determine relationships between extraocular motoneuron firing and eye movement. We recorded abducens nucleus neurons in mice executing compensatory eye movements during 0.1- to 1.6-Hz oscillation in the light. We analyzed firing rates to extract eye position and eye velocity sensitivities, from which we determined time constants of a viscoelastic model of the plant. The majority of abducens neurons were already active with the eye in its central rest position, with only 6% recruited at more abducted positions. Firing rates exhibited largely linear relationships to eye movement, although there was a nonlinearity consisting of increasing modulation in proportion to eye movement as eye amplitudes became small (due to reduced stimulus amplitude or reduced alertness). Eye position and velocity sensitivities changed with stimulus frequency as expected for an ocular motor plant dominated by cascaded viscoelasticities. Transfer function poles lay at approximately 0.1 and 0.9 s. Compared with previously studied animal species, the mouse plant is stiffer than the rabbit but laxer than cat and rhesus. Differences between mouse and rabbit can be explained by scaling for eye size (allometry). Differences between the mouse and cat or rhesus can be explained by differing ocular motor repertoires of animals with and without a fovea or area centralis.


Asunto(s)
Neuronas Motoras/fisiología , Puente/fisiología , Animales , Potenciales Evocados Motores , Medidas del Movimiento Ocular , Movimientos Oculares/fisiología , Ratones , Ratones Endogámicos C57BL , Músculos Oculomotores/inervación , Músculos Oculomotores/fisiología , Especificidad de la Especie
14.
Clin Lung Cancer ; 23(7): e408-e414, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35680550

RESUMEN

OBJECTIVES: The ideal non-operative treatment for patients with large, node-negative non-small cell lung cancer (NSCLC) is poorly defined. To inform optimal treatment paradigms for this cohort, we examined patterns of failure and the impact of radiation therapy (RT) and chemotherapy receipt. MATERIALS AND METHODS: Node-negative NSCLC patients with 5+ cm primary tumors receiving definitive RT at our institution were identified. Sites of initial progression were analyzed. Local progression, regional/distant progression, progression-free survival, and overall survival were analyzed via cumulative incidence function and Kaplan-Meier. Associations between local vs. regional/distant progression with treatment and clinicopathologic variables were assessed via univariable and multivariable competing risks regression. RESULTS AND CONCLUSION: We identified 88 patients for analysis. Among patients with recurrent disease (N = 36), initial patterns of failure analysis showed that isolated distant (27.8%) and isolated regional progression (22.2%) were most common. Distant or regional failure as a component of initial failure was seen in 88.9% of patients who progressed, while isolated local failure was uncommon (11.1%). Univariable and multivariable competing risks regression showed that receipt of SBRT was associated with reduced risk of local progression (HR 0.23, P = .012), and receipt of chemotherapy was associated with reduced risk of regional/distant progression (HR 0.12, P = .040). In conclusion, patients with large, node-negative NSCLC treated with definitive RT are at high risk of regional and distant progression. SBRT correlates with a reduced risk of local failure while chemotherapy is associated with reduced regional/distant progression in this patient population. Ideal treatment may include SBRT when feasible with appropriate systemic therapy.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Radiocirugia , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/patología , Radiocirugia/métodos , Supervivencia sin Progresión , Estudios de Cohortes , Resultado del Tratamiento , Estudios Retrospectivos
15.
Ann Neurol ; 67(5): 676-80, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20437565

RESUMEN

We conducted a masked, crossover, therapeutic trial of gabapentin (1,200mg/day) versus memantine (40 mg/day) for acquired nystagmus in 10 patients (aged 28-61 years; 7 female; 3 multiple sclerosis [MS]; 6 post-stroke; 1 post-traumatic). Nystagmus was pendular in 6 patients (4 oculopalatal tremor; 2 MS) and jerk upbeat, hemi-seesaw, torsional, or upbeat-diagonal in each of the others. For the group, both drugs reduced median eye speed (p < 0.001), gabapentin by 32.8% and memantine by 27.8%, and improved visual acuity (p < 0.05). Each patient improved with 1 or both drugs. Side effects included unsteadiness with gabapentin and lethargy with memantine. Both drugs should be considered as treatment for acquired forms of nystagmus.


Asunto(s)
Aminas/uso terapéutico , Ácidos Ciclohexanocarboxílicos/uso terapéutico , Antagonistas de Aminoácidos Excitadores/uso terapéutico , Memantina/uso terapéutico , Nistagmo Patológico/tratamiento farmacológico , Ácido gamma-Aminobutírico/uso terapéutico , Adulto , Estudios Cruzados , Movimientos Oculares/efectos de los fármacos , Femenino , Gabapentina , Humanos , Masculino , Persona de Mediana Edad
16.
Electrophoresis ; 32(12): 1492-9, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21563180

RESUMEN

In this paper, we demonstrate, using both experiment and simulation, how sample zone conductivity can affect plug-plug mixing in small molecule applications of electrophoretically mediated microanalysis (EMMA). The effectiveness of in-line mixing, which is driven by potential, can vary widely with experimental conditions. Using two small molecule systems, the effects of local conductivity differences between analyte plugs, reagent plugs and the BGE on EMMA analyses are examined. Simul 5.0, a dynamic simulation program for CE systems, is used to understand the ionic boundaries and profiles that give rise to the experimentally obtained data for EMMA analyses for (i) creatinine determination via the Jaffe reaction, a reaction involving a neutral and an anion, and (ii) the redox reaction between gallate and 2,6-dichloroindophenol, two anions. Low sample conductivity, which is widely used in CE analyses, can be detrimental for in-line reactions involving a neutral reactant, as rapid migration of the ionic component across a low conductivity neutral zone results in poor reagent plug overlap and low reaction efficiency. Conversely, with two similarly charged reagents, a low conductivity sample plug is advantageous, as it allows field-amplified stacking of the reagents into a tight reaction zone. In addition, the complexity of simultaneously overlapping three reagent zones is considered, and experimental results validate the predictions made by the simulation. The simulations, however, do not appear to predict all of the observed experimental behavior. Overall, by combining experiment with simulation, an enhanced appreciation for the local field effects in EMMA is realized, and general guidelines for an advantageous sample matrix can be established for categories of EMMA analyses.


Asunto(s)
Conductividad Eléctrica , Electroforesis Capilar/métodos , Modelos Químicos , 2,6-Dicloroindofenol/química , Aniones/química , Simulación por Computador , Creatinina/química , Ácido Gálico/química , Picratos/química
17.
J Appl Meas ; 12(4): 399-426, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22357160

RESUMEN

This article discusses the strengths and weakness of the Angoff and Bookmark standard setting procedures. An alternative approach that focuses on the strengths of these procedures and adds three diagnostic indices is presented. This alternative approach is applied to three standard setting data sets and the results are discussed.


Asunto(s)
Pruebas de Aptitud/normas , Evaluación Educacional/normas , Concesión de Licencias/normas , Estándares de Referencia , Gráficos por Computador , Consenso , Humanos , Cómputos Matemáticos , Psicometría/estadística & datos numéricos , Reproducibilidad de los Resultados
18.
Clin Lung Cancer ; 22(5): e716-e722, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33658160

RESUMEN

BACKGROUND: Radiation pneumonitis (RP) is a dose-limiting and potentially fatal toxicity of thoracic radiotherapy most often seen in patients treated for primary lung cancer. The purpose of this study was to identify predictors of in-hospital death among lung cancer patients admitted for acute RP in the Healthcare Cost and Utilization Project (HCUP) database. MATERIALS AND METHODS: The HCUP National Inpatient Sample database was queried from 2012 through 2016 to capture adult lung cancer patients admitted to the hospital with a principal diagnosis of acute RP. Multivariate logistic regression modeling and χ2 tests were used to determine predictors of in-hospital death. RESULTS: Of the 882 patients with lung cancer admitted for RP, 67 patients (7.6%) died during the hospitalization and 90 patients (10.2%) required mechanical ventilation. Of those requiring mechanical ventilation, 38 patients (42.2%) died. The average age at hospitalization was 70.4 years (range, 35-90). Of those factors associated with death on univariate analysis, interstitial lung disease (odds ratio [OR] = 6.14; 95% confidence interval [CI], 1.9-19.4; P = .002), pulmonary hypertension (OR = 3.1; 95% CI, 1.6-6.2; P = .001), diabetes mellitus (OR = 2.0; 95% CI, 1.1-3.3; P = .013), and more affluent Zip Code (OR = 1.9; 95% CI, 1.1-3.2; P = .021) remained statistically significant on multivariate logistic regression. CONCLUSION: In the largest reported cohort of patients with lung cancer hospitalized with a principal diagnosis of acute RP, the presence of interstitial lung disease, pulmonary hypertension, diabetes mellitus, and more affluent Zip Code were associated with in-hospital death. Comorbid diagnoses may be useful for risk-stratified management of inpatients with RP.


Asunto(s)
Costos de la Atención en Salud , Mortalidad Hospitalaria/tendencias , Neoplasias Pulmonares/radioterapia , Aceptación de la Atención de Salud , Neumonitis por Radiación , Anciano , Bases de Datos Factuales , Femenino , Predicción , Humanos , Modelos Logísticos , Masculino , Estudios Retrospectivos
19.
Acad Emerg Med ; 28(7): 718-744, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34228849

RESUMEN

This first Guideline for Reasonable and Appropriate Care in the Emergency Department (GRACE-1) from the Society for Academic Emergency Medicine is on the topic: Recurrent, Low-risk Chest Pain in the Emergency Department. The multidisciplinary guideline panel used The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to assess the certainty of evidence and strength of recommendations regarding eight priority questions for adult patients with recurrent, low-risk chest pain and have derived the following evidence based recommendations: (1) for those >3 h chest pain duration we suggest a single, high-sensitivity troponin below a validated threshold to reasonably exclude acute coronary syndrome (ACS) within 30 days; (2) for those with a normal stress test within the previous 12 months, we do not recommend repeat routine stress testing as a means to decrease rates of major adverse cardiac events at 30 days; (3) insufficient evidence to recommend hospitalization (either standard inpatient admission or observation stay) versus discharge as a strategy to mitigate major adverse cardiac events within 30 days; (4) for those with non-obstructive (<50% stenosis) coronary artery disease (CAD) on prior angiography within 5 years, we suggest referral for expedited outpatient testing as warranted rather than admission for inpatient evaluation; (5) for those with no occlusive CAD (0% stenosis) on prior angiography within 5 years, we recommend referral for expedited outpatient testing as warranted rather than admission for inpatient evaluation; (6) for those with a prior coronary computed tomographic angiography within the past 2 years with no coronary stenosis, we suggest no further diagnostic testing other than a single, normal high-sensitivity troponin below a validated threshold to exclude ACS within that 2 year time frame; (7) we suggest the use of depression and anxiety screening tools as these might have an effect on healthcare use and return emergency department (ED) visits; and (8) we suggest referral for anxiety or depression management, as this might have an impact on healthcare use and return ED visits.


Asunto(s)
Síndrome Coronario Agudo , Dolor en el Pecho , Síndrome Coronario Agudo/complicaciones , Síndrome Coronario Agudo/diagnóstico , Síndrome Coronario Agudo/terapia , Adulto , Dolor en el Pecho/diagnóstico , Dolor en el Pecho/etiología , Dolor en el Pecho/terapia , Angiografía Coronaria , Servicio de Urgencia en Hospital , Prueba de Esfuerzo , Hospitalización , Humanos , Medición de Riesgo
20.
Adv Radiat Oncol ; 6(5): 100743, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34466713

RESUMEN

PURPOSE: The number of US fourth-year medical students applying to radiation oncology has decreased during the past few years. We conducted a survey of fourth-year medical students to examine factors that may be influencing the decision to pursue radiation oncology. METHODS AND MATERIALS: An anonymous online survey was sent to medical students at 9 participating US medical schools. RESULTS: A total of 232 medical students completed the survey. Of the 153 students who stated they were never interested in radiation oncology, 77 (50%) reported never having been exposed to the specialty as their reason for not pursuing radiation oncology. The job market was the most commonly cited factor among students who said they were once interested in but ultimately chose not to pursue radiation oncology. Conversely, the recent low pass rates for board examinations and a perception of a lack of diversity within radiation oncology had the least influence. CONCLUSIONS: Despite discussion of potential measures to address this disquieting trend, there have been minimal formal attempts to characterize and address potential causes of a decreasing interest in radiation oncology. This study's data are consistent with previous research regarding the trend of decreased medical student interest in radiation oncology and may be used as part of ongoing introspective assessment to inform future change within radiation oncology.

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