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1.
N Engl J Med ; 384(17): 1613-1622, 2021 04 29.
Artículo en Inglés | MEDLINE | ID: mdl-33838625

RESUMEN

BACKGROUND: Outcomes in children and adolescents with recurrent or progressive high-grade glioma are poor, with a historical median overall survival of 5.6 months. Pediatric high-grade gliomas are largely immunologically silent or "cold," with few tumor-infiltrating lymphocytes. Preclinically, pediatric brain tumors are highly sensitive to oncolytic virotherapy with genetically engineered herpes simplex virus type 1 (HSV-1) G207, which lacks genes essential for replication in normal brain tissue. METHODS: We conducted a phase 1 trial of G207, which used a 3+3 design with four dose cohorts of children and adolescents with biopsy-confirmed recurrent or progressive supratentorial brain tumors. Patients underwent stereotactic placement of up to four intratumoral catheters. The following day, they received G207 (107 or 108 plaque-forming units) by controlled-rate infusion over a period of 6 hours. Cohorts 3 and 4 received radiation (5 Gy) to the gross tumor volume within 24 hours after G207 administration. Viral shedding from saliva, conjunctiva, and blood was assessed by culture and polymerase-chain-reaction assay. Matched pre- and post-treatment tissue samples were examined for tumor-infiltrating lymphocytes by immunohistologic analysis. RESULTS: Twelve patients 7 to 18 years of age with high-grade glioma received G207. No dose-limiting toxic effects or serious adverse events were attributed to G207 by the investigators. Twenty grade 1 adverse events were possibly related to G207. No virus shedding was detected. Radiographic, neuropathological, or clinical responses were seen in 11 patients. The median overall survival was 12.2 months (95% confidence interval, 8.0 to 16.4); as of June 5, 2020, a total of 4 of 11 patients were still alive 18 months after G207 treatment. G207 markedly increased the number of tumor-infiltrating lymphocytes. CONCLUSIONS: Intratumoral G207 alone and with radiation had an acceptable adverse-event profile with evidence of responses in patients with recurrent or progressive pediatric high-grade glioma. G207 converted immunologically "cold" tumors to "hot." (Supported by the Food and Drug Administration and others; ClinicalTrials.gov number, NCT02457845.).


Asunto(s)
Neoplasias Encefálicas/terapia , Glioma/terapia , Viroterapia Oncolítica , Adolescente , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/radioterapia , Niño , Preescolar , Terapia Combinada , Femenino , Glioma/diagnóstico por imagen , Glioma/patología , Glioma/radioterapia , Humanos , Estimación de Kaplan-Meier , Células Asesinas Naturales , Recuento de Leucocitos , Masculino , Viroterapia Oncolítica/efectos adversos , Linfocitos T
2.
J Pediatr ; 268: 113934, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38309519

RESUMEN

OBJECTIVE: The objective of this study was to determine if valganciclovir initiated after 1 month of age improves congenital cytomegalovirus-associated sensorineural hearing loss. STUDY DESIGN: We conducted a randomized, double-blind, placebo-controlled phase 2 trial of 6 weeks of oral valganciclovir at US (n = 12) and UK (n = 9) sites. Patients of ages 1 month through 3 years with baseline sensorineural hearing loss were enrolled. The primary outcome was change in total ear hearing between baseline and study month 6. Secondary outcome measures included change in best ear hearing and reduction in cytomegalovirus viral load in blood, saliva, and urine. RESULTS: Of 54 participants enrolled, 35 were documented to have congenital cytomegalovirus infection and were randomized (active group: 17; placebo group: 18). Mean age at enrollment was 17.8 ± 15.8 months (valganciclovir) vs 19.5 ± 13.1 months (placebo). Twenty (76.9%) of the 26 ears from subjects in the active treatment group did not have worsening of hearing, compared with 27 (96.4%) of 28 ears from subjects in the placebo group (P = .09). All other comparisons of total ear or best ear hearing outcomes were also not statistically significant. Saliva and urine viral loads decreased significantly in the valganciclovir group but did not correlate with change in hearing outcome. CONCLUSIONS: In this randomized controlled trial, initiation of antiviral therapy beyond the first month of age did not improve hearing outcomes in children with congenital cytomegalovirus-associated sensorineural hearing loss. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT01649869.


Asunto(s)
Antivirales , Infecciones por Citomegalovirus , Ganciclovir , Pérdida Auditiva Sensorineural , Valganciclovir , Humanos , Infecciones por Citomegalovirus/tratamiento farmacológico , Infecciones por Citomegalovirus/congénito , Infecciones por Citomegalovirus/complicaciones , Valganciclovir/uso terapéutico , Valganciclovir/administración & dosificación , Pérdida Auditiva Sensorineural/tratamiento farmacológico , Pérdida Auditiva Sensorineural/virología , Pérdida Auditiva Sensorineural/etiología , Antivirales/uso terapéutico , Antivirales/administración & dosificación , Masculino , Femenino , Método Doble Ciego , Lactante , Administración Oral , Ganciclovir/análogos & derivados , Ganciclovir/uso terapéutico , Ganciclovir/administración & dosificación , Preescolar , Resultado del Tratamiento , Carga Viral , Recién Nacido
3.
Pediatr Res ; 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39147903

RESUMEN

BACKGROUND: Incubator oxygen may improve respiratory stability in preterm infants compared with nasal cannula oxygen. METHODS: Single center randomized trial of infants <29 weeks' gestation on supplemental oxygen at ≥32 weeks' postmenstrual age. Infants were crossed-over every 24 hours for 96 hours between incubator oxygen and nasal cannula ≤1.0 L/kg/min. We measured episodes of intermittent hypoxemia (oxygen saturations (SpO2) < 85% ≥10 seconds), bradycardia, cerebral and abdominal hypoxemia, and end-tidal carbon dioxide. RESULTS: We enrolled 25 infants with a gestational age of 26 weeks 4 days±15 days (mean ± SD) and birth weight 805 ± 202 grams. There were no differences in episodes of intermittent hypoxemia, bradycardia, or cerebral hypoxemia between groups. There were fewer episodes of abdominal hypoxemia <40% ≥10 seconds with incubator oxygen compared with nasal cannula (132 ± 130 versus 158 ± 125; p < 0.01). Time with SpO2 < 85% and abdominal hypoxemia was lower among infants on incubator oxygen. Carbon dioxide values were higher while on incubator oxygen (41 ± 11 versus 36 ± 10 mmHg; p < 0.02). CONCLUSION: There was no difference in intermittent hypoxemia between incubator and nasal cannula oxygen among preterm infants on supplemental oxygen. Infants had higher levels of carbon dioxide while on incubator oxygen, which may have improved some measures of respiratory stability. CLINCALTRIALS. GOV IDENTIFIERS: NCT03333174 and NCT03174301. IMPACT STATEMENT: In this randomized cross-over trial of preterm infants on supplemental oxygen, incubator oxygen did not decrease episodes of intermittent hypoxemia compared with nasal cannula oxygen. Incubator oxygen reduced time with oxygen saturations less than 85%, reduced abdominal hypoxemia, and increased carbon dioxide levels. Differences in measures of respiratory stability on incubator oxygen may be partly due to higher carbon dioxide levels compared with nasal cannula oxygen. The mode of supplemental oxygen administration may impact control of breathing in preterm infants through its effect on hypopharyngeal oxygen stability and carbon dioxide levels.

4.
Transpl Infect Dis ; 26(2): e14237, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38341645

RESUMEN

BACKGROUND: BK polyomavirus (BKV) can cause permanent loss of allograft function due to BKV-associated nephropathy (BKVN) in kidney transplant recipients. Besides immunosuppression reduction, there are no consistently effective interventions for BKV infection. Study purpose was to define natural history of BKV infection, identify risk factors for BKV reactivation and BKVN in kidney transplant recipients, and inform the design/conduct of future clinical trials of BKV-targeted therapeutics. METHODS: We conducted a multicenter prospective observational study of incident kidney transplant recipients at six U.S. transplant centers. Participants were monitored every 4 weeks for BKV reactivation and followed for up to 24 months post-transplant. We used regression models (logistic, survival, mixed models) to study relationships between BK viremia/BKVN, clinical characteristics, and allograft function. RESULTS: We enrolled 335 participants. Fifty-eight (17%) developed BK viremia, 6 (2%) developed biopsy-proven BKVN, and 29 (9%) developed suspected/presumed BKVN (defined as BKV viral load > 10,000 copies/mL without biopsy). Male donor sex was associated with lower odds for BK viremia, whereas recipient Black race was associated with two-fold increased odds for BK viremia. Recipient female sex was associated with more rapid clearance of BK viremia. Persistent BK viremia/BKVN was associated with poorer allograft function by 24 months post-transplant. CONCLUSIONS: We identified multiple donor and recipient demographic factors associated with risk for BKV infection and poorer allograft function by 24 months post-transplant. This may help design future clinical trials of therapies to prevent or mitigate the deleterious impact of BKV reactivation on kidney transplant outcomes.


Asunto(s)
Virus BK , Enfermedades Renales , Trasplante de Riñón , Infecciones por Polyomavirus , Infecciones Tumorales por Virus , Humanos , Masculino , Femenino , Trasplante de Riñón/efectos adversos , Estudios Prospectivos , Viremia/complicaciones , Infecciones por Polyomavirus/complicaciones , Infecciones Tumorales por Virus/tratamiento farmacológico
5.
Pediatr Nephrol ; 39(7): 2245-2251, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38438560

RESUMEN

BACKGROUND: Prophylactic peritoneal dialysis (PD) in neonates undergoing cardiopulmonary bypass (CPB) is safe and improves outcomes. We sought to (1) derive the pre-operative characteristics of neonates who are most likely to benefit from PD after CPB and (2) validate a new prophylactic PD protocol based on our retrospective analysis. METHODS: First, we retrospectively evaluated neonates requiring cardiac surgery with CPB from October 2012 to June 2016. We categorized neonates as those who "needed PD" and those who "did not need PD" based on prior experience with neonates requiring kidney support therapy. Pre-operative serum creatinine ≥ 0.8 mg/dL, pre-operative weight ≤ 2.5 kg, or having an open chest post-operatively were independently associated with "needed PD." Next, beginning in March 2019, we implemented a new prophylactic PD protocol in which only those who met at least one of the three criteria derived in the retrospective analysis had a PD catheter placed in the OR. RESULTS: In Era 2, after the implementation of a new prophylactic PD protocol, 100% of neonates in the "needed PD" group had a PD catheter placed in the OR, which was more than in the prior era (Era 1 = 86.6%) (p = 0.05). Only 26.1% in the "did not need PD" group had a PD catheter placed in the OR which was less than in the prior era (Era 1 = 50.6%) (p < 0.01). CONCLUSIONS: We successfully developed and implemented an evidence-based prophylactic PD protocol that has improved our ability to provide prophylactic PD in neonates after CPB.


Asunto(s)
Puente Cardiopulmonar , Diálisis Peritoneal , Humanos , Diálisis Peritoneal/efectos adversos , Estudios Retrospectivos , Recién Nacido , Masculino , Femenino , Puente Cardiopulmonar/efectos adversos , Puente Cardiopulmonar/métodos , Complicaciones Posoperatorias/prevención & control , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/diagnóstico , Protocolos Clínicos , Creatinina/sangre , Lesión Renal Aguda/prevención & control , Lesión Renal Aguda/etiología , Lesión Renal Aguda/diagnóstico
6.
J Pediatr Hematol Oncol ; 46(6): 322-326, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38652051

RESUMEN

Lymphadenopathy is a common reason for referral to a subspecialist, which may result in significant anxiety for parents. Understanding which patients require a subspecialty referral for lymphadenopathy is key to streamlining health care utilization for this common clinical entity. This is an IRB-approved retrospective study examining pediatric patients consecutively referred to pediatric hematology oncology, otolaryngology, or surgery for lymphadenopathy from 2012 to 2021 at a free-standing tertiary-care children's hospital. Logistic regression was fitted to examine the association between the maximum size of the lymph nodes (LN) and a diagnosis of malignancy. The odds ratio, area under the receiver operator curve, sensitivity, and specificity were estimated. We found a significant association between LN size and cancer diagnosis. For every centimeter increase in the maximal dimension of LN, there was an estimated 2.3 times increase in the odds of malignancy (OR=2.3, 95% CI: 1.65-3.11; P <0.0001). The estimated area under the curve (0.84, 95% CI: 0.78-0.90) indicated that LN size correlated well with cancer diagnosis. A LN cut-off size of 2 cm resulted in an estimated sensitivity of 1.0 (95% CI: 0.87-1.00) and specificity of 0.54 (95% CI: 0.46-0.61). Maximum LN size may be a predictor of malignancy among pediatric patients with lymphadenopathy.


Asunto(s)
Linfadenopatía , Derivación y Consulta , Humanos , Linfadenopatía/patología , Niño , Masculino , Derivación y Consulta/estadística & datos numéricos , Femenino , Estudios Retrospectivos , Adolescente , Preescolar , Lactante , Neoplasias/patología , Ganglios Linfáticos/patología
7.
Physiol Genomics ; 55(4): 194-212, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36939205

RESUMEN

Acute exercise elicits dynamic transcriptional changes that, when repeated, form the fundamental basis of health, resilience, and performance adaptations. While moderate-intensity endurance training combined with conventional resistance training (traditional, TRAD) is often prescribed and recommended by public health guidance, high-intensity training combining maximal-effort intervals with intensive, limited-rest resistance training is a time-efficient alternative that may be used tactically (HITT) to confer similar benefits. Mechanisms of action of these distinct stimuli are incompletely characterized and have not been directly compared. We assessed transcriptome-wide responses in skeletal muscle and circulating extracellular vesicles (EVs) to a single exercise bout in young adults randomized to TRAD (n = 21, 12 M/9 F, 22 ± 3 yr) or HITT (n = 19, 11 M/8 F, 22 ± 2 yr). Next-generation sequencing captured small, long, and circular RNA in muscle and EVs. Analysis identified differentially expressed transcripts (|log2FC|>1, FDR ≤ 0.05) immediately (h0, EVs only), h3, and h24 postexercise within and between exercise protocols. In aaddition, all apparently responsive transcripts (FDR < 0.2) underwent singular value decomposition to summarize data structures into latent variables (LVs) to deconvolve molecular expression circuits and interregulatory relationships. LVs were compared across time and exercise protocol. TRAD, a longer but less intense stimulus, generally elicited a stronger transcriptional response than HITT, but considerable overlap and key differences existed. Findings reveal shared and unique molecular responses to the exercise stimuli and lay groundwork toward establishing relationships between protein-coding genes and lesser-understood transcripts that serve regulatory roles following exercise. Future work should advance the understanding of these circuits and whether they repeat in other populations or following other types of exercise/stress.NEW & NOTEWORTHY We examined small and long transcriptomics in skeletal muscle and serum-derived extracellular vesicles before and after a single exposure to traditional combined exercise (TRAD) and high-intensity tactical training (HITT). Across 40 young adults, we found more consistent protein-coding gene responses to TRAD, whereas HITT elicited differential expression of microRNA enriched in brain regions. Follow-up analysis revealed relationships and temporal dynamics across transcript networks, highlighting potential avenues for research into mechanisms of exercise response and adaptation.


Asunto(s)
Entrenamiento de Fuerza , Transcriptoma , Humanos , Adulto Joven , Transcriptoma/genética , Ejercicio Físico/fisiología , Perfilación de la Expresión Génica , Músculo Esquelético/metabolismo
8.
Genet Epidemiol ; 46(1): 17-31, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34672390

RESUMEN

Mendelian randomization (MR) is an application of instrumental variable (IV) methods to observational data in which the IV is a genetic variant. MR methods applicable to the general exponential family of distributions are currently not well characterized. We adapt a general linear model framework to the IV setting and propose a general MR method applicable to any full-rank distribution from the exponential family. Empirical bias and coverage are estimated via simulations. The proposed method is compared to several existing MR methods. Real data analyses are performed using data from the REGARDS study to estimate the potential causal effect of smoking frequency on stroke risk in African Americans. In simulations with binary variates and very weak instruments the proposed method had the lowest median [Q1 , Q3 ] bias (0.10 [-3.68 to 3.62]); compared with 2SPS (0.27 [-3.74 to 4.26]) and the Wald method (-0.69 [-1.72 to 0.35]). Low bias was observed throughout other simulation scenarios; as well as more than 90% coverage for the proposed method. In simulations with count variates, the proposed method performed comparably to 2SPS; the Wald method maintained the most consistent low bias; and 2SRI was biased towards the null. Real data analyses find no evidence for a causal effect of smoking frequency on stroke risk. The proposed MR method has low bias and acceptable coverage across a wide range of distributional scenarios and instrument strengths; and provides a more parsimonious framework for asymptotic hypothesis testing compared to existing two-stage procedures.


Asunto(s)
Análisis de la Aleatorización Mendeliana , Fumar , Causalidad , Humanos , Modelos Lineales , Análisis de la Aleatorización Mendeliana/métodos , Modelos Genéticos , Fumar/genética
9.
Muscle Nerve ; 67(1): 25-32, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36324261

RESUMEN

INTRODUCTION/AIMS: Factors associated with coronavirus disease 2019 (COVID-19) infection among the myasthenia gravis (MG) population are incompletely understood. This study aimed to characterize the behavior of MG patients during the pandemic and to examine risk factors associated with COVID-19 infection. METHODS: A "COVID-19 Survey" was sent to MG Patient Registry participants in the summer of 2020 (CSS20) and winter of 2021 (CWS21). Survey results were summarized descriptively. Demographics, disease characteristics, medication use, and survey results were compared between those reporting COVID-19 diagnosis (COVID), COVID-19 like symptoms without diagnosis (COVID-Like), and asymptomatic participants. RESULTS: A total of 454 and 665 participants completed the CSS20 and CWS21 surveys respectively; 326 participants completed both. Most continued follow-up visits and MG treatments. The frequency of COVID-like symptoms was similar between CSS20 and CWS21, while COVID-19 exposure (6% vs. 27%), COVID-19 testing among symptomatic individuals (35% vs. 78%), and COVID-19 diagnosis (0.2% vs. 6%) were higher in the CWS21. Cough, fever, fatigue, myalgia, anosmia/ageusia, and hospital and intensive care unit (ICU) admissions were more frequent in the COVID compared to the COVID-Like group. COVID-19 exposure (odds ratio [OR] 7.88), number of people in the household (OR 1.31), and report of MG exacerbation before the pandemic (OR 2.6) were independently associated with COVID-19 infection. DISCUSSION: COVID-19 affected MG patients increasingly through the early pandemic. While face-to-face contact with a COVID-19 infected individual was an obvious risk factor, MG patients who had more people in the household and unstable disease were at elevated risk for COVID-19 infection.


Asunto(s)
COVID-19 , Miastenia Gravis , Humanos , COVID-19/epidemiología , COVID-19/complicaciones , Pandemias , Prueba de COVID-19 , Miastenia Gravis/diagnóstico , Sistema de Registros
10.
Proc Natl Acad Sci U S A ; 117(48): 30649-30660, 2020 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-33199596

RESUMEN

Myasthenia gravis (MG) is a neuromuscular, autoimmune disease caused by autoantibodies that target postsynaptic proteins, primarily the acetylcholine receptor (AChR) and inhibit signaling at the neuromuscular junction. The majority of patients under 50 y with AChR autoantibody MG have thymic lymphofollicular hyperplasia. The MG thymus is a reservoir of plasma cells that secrete disease-causing AChR autoantibodies and although thymectomy improves clinical scores, many patients fail to achieve complete stable remission without additional immunosuppressive treatments. We speculate that thymus-associated B cells and plasma cells persist in the circulation after thymectomy and that their persistence could explain incomplete responses to resection. We studied patients enrolled in a randomized clinical trial and used complementary modalities of B cell repertoire sequencing to characterize the thymus B cell repertoire and identify B cell clones that resided in the thymus and circulation before and 12 mo after thymectomy. Thymus-associated B cell clones were detected in the circulation by both mRNA-based and genomic DNA-based sequencing. These antigen-experienced B cells persisted in the circulation after thymectomy. Many circulating thymus-associated B cell clones were inferred to have originated and initially matured in the thymus before emigration from the thymus to the circulation. The persistence of thymus-associated B cells correlated with less favorable changes in clinical symptom measures, steroid dose required to manage symptoms, and marginal changes in AChR autoantibody titer. This investigation indicates that the diminished clinical response to thymectomy is related to persistent circulating thymus-associated B cell clones.


Asunto(s)
Linfocitos B/metabolismo , Recuento de Linfocitos , Miastenia Gravis/sangre , Timo/metabolismo , Adolescente , Adulto , Autoanticuerpos/inmunología , Linfocitos B/inmunología , Biomarcadores , Evolución Clonal/genética , Selección Clonal Mediada por Antígenos , Susceptibilidad a Enfermedades , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Biológicos , Miastenia Gravis/etiología , Radioinmunoensayo , Receptores Colinérgicos/inmunología , Timectomía , Timo/citología , Timo/inmunología , Recombinación V(D)J , Adulto Joven
11.
Physiol Genomics ; 54(12): 501-513, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36278270

RESUMEN

The ability of individuals with end-stage osteoarthritis (OA) to functionally recover from total joint arthroplasty is highly inconsistent. The molecular mechanisms driving this heterogeneity have yet to be elucidated. Furthermore, OA disproportionately impacts females, suggesting a need for identifying female-specific therapeutic targets. We profiled the skeletal muscle transcriptome in females with end-stage OA (n = 20) undergoing total knee or hip arthroplasty using RNA-Seq. Single-gene differential expression (DE) analyses tested for DE genes between skeletal muscle overlaying the surgical (SX) joint and muscle from the contralateral (CTRL) leg. Network analyses were performed using Pathway-Level Information ExtractoR (PLIER) to summarize genes into latent variables (LVs), i.e., gene circuits, and link them to biological pathways. LV differences in SX versus CTRL muscle and across sources of muscle tissue (vastus medialis, vastus lateralis, or tensor fascia latae) were determined with ANOVA. Linear models tested for associations between LVs and muscle phenotype on the SX side (inflammation, function, and integrity). DE analysis revealed 360 DE genes (|Log2 fold-difference| ≥ 1, FDR ≤ 0.05) between the SX and CTRL limbs, many associated with inflammation and lipid metabolism. PLIER analyses revealed circuits associated with protein degradation and fibro-adipogenic cell gene expression. Muscle inflammation and function were linked to an LV associated with endothelial cell gene expression highlighting a potential regulatory role of endothelial cells within skeletal muscle. These findings may provide insight into potential therapeutic targets to improve OA rehabilitation before and/or following total joint replacement.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Artroplastia de Reemplazo de Rodilla , Osteoartritis , Femenino , Humanos , Células Endoteliales , Articulación de la Rodilla , Osteoartritis/genética , Músculo Esquelético
12.
Genet Epidemiol ; 45(5): 549-560, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33998053

RESUMEN

BACKGROUND: Mendelian randomization (MR) applies instrumental variable (IV) methods to observational data using a genetic variant as an IV. Several Monte-Carlo studies investigate the performance of MR methods with binary outcomes, but few consider them in conjunction with binary risk factors. OBJECTIVE: To develop a novel MR estimator for scenarios with a binary risk factor and outcome; and compare to existing MR estimators via simulations and real data analysis. METHODS: A bivariate Bernoulli distribution is adapted to the IV setting. Empirical bias and asymptotic coverage probabilities are estimated via simulations. The proposed method is compared to the Wald method, two-stage predictor substitution (2SPS), two-stage residual inclusion (2SRI), and the generalized method of moments (GMM). An analysis is performed using existing data from the CLEAR study to estimate the potential causal effect of smoking on rheumatoid arthritis risk in African Americans. RESULTS: Bias was low for the proposed method and comparable to 2SPS. The Wald method was often biased towards the null. Coverage was adequate for the proposed method, 2SPS, and 2SRI. Coverage for the Wald and GMM methods was poor in several scenarios. The causal effect of ever smoking on rheumatoid arthritis risk was not statistically significant using a variety of genetic instruments. CONCLUSIONS: Simulations suggest the proposed MR method is sound with binary risk factors and outcomes, and comparable to 2SPS and 2SRI in terms of bias. The proposed method also provides more natural framework for hypothesis testing compared to 2SPS or 2SRI, which require ad-hoc variance adjustments.


Asunto(s)
Análisis de la Aleatorización Mendeliana , Fumar , Causalidad , Humanos , Modelos Genéticos , Factores de Riesgo , Fumar/efectos adversos , Fumar/genética
13.
Muscle Nerve ; 66(4): 411-420, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35673964

RESUMEN

INTRODUCTION/AIMS: We studied the progression of myasthenia gravis (MG) disease burden and medication adjustment among MG Patient Registry participants. METHODS: Participants diagnosed with MG (age ≥18 years), registered between July 1, 2013 and July 31, 2018 and completing both 6- and 12-month follow-up surveys, were included in this investigation. Participants were grouped into high-burden (Myasthenia Gravis Activity of Daily Living scale [MG-ADL] score ≥6) and low-burden (MG-ADL <6) groups based on MG-ADL scores at enrollment. Demographics and disease history were compared between groups. MG-ADL score change and medication changes (escalation, no change, de-escalation) between enrollment and 12-month follow-up were compared between groups. Minimal symptom expression (MSE, MG-ADL <2) at 12 months was compared between groups. Logistic regression analysis was performed to study factors associated with MSE at 12 months. RESULTS: In total, 520 participants (56% female) were included in high-burden (n = 248) and low-burden (n = 272) groups. Those in the high-burden group were more likely to be younger, female, and have shorter disease duration. At 12 months, MSE was achieved in 6% of the high-burden group and newly achieved (42 of 201, 21%) or maintained (52 of 71, 73%) in the low-burden group. In the multivariable analysis, being in the high-burden group and use of pyridostigmine were associated with less likelihood of MSE, whereas MG-ADL score improvement (>2 or >20%) at 6 months significantly increased the likelihood of achieving MSE at 12 months (P = .0004). DISCUSSION: In both groups, but more so in the high-burden group, patients infrequently achieved MSE after 1 year of MG treatment. Baseline low disease burden, improvement at 6 months and no pyridostigmine use were associated with a higher likelihood of MSE at 12 months.


Asunto(s)
Actividades Cotidianas , Miastenia Gravis , Adolescente , Costo de Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Miastenia Gravis/diagnóstico , Bromuro de Piridostigmina/uso terapéutico , Sistema de Registros
14.
J Stat Plan Inference ; 217: 141-152, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36911105

RESUMEN

Spike-and-slab priors model predictors as arising from a mixture of distributions: those that should (slab) or should not (spike) remain in the model. The spike-and-slab lasso (SSL) is a mixture of double exponentials, extending the single lasso penalty by imposing different penalties on parameters based on their inclusion probabilities. The SSL was extended to Generalized Linear Models (GLM) for application in genetics/genomics, and can handle many highly correlated predictors of a scalar outcome, but does not incorporate these relationships into variable selection. When images/spatial data are used to model a scalar outcome, relevant parameters tend to cluster spatially, and model performance may benefit from incorporating spatial structure into variable selection. We propose to incorporate spatial information by assigning intrinsic autoregressive priors to the logit prior probabilities of inclusion, which results in more similar shrinkage penalties among spatially adjacent parameters. Using MCMC to fit Bayesian models can be computationally prohibitive for large-scale data, but we fit the model by adapting a computationally efficient coordinate-descent-based EM algorithm. A simulation study and an application to Alzheimer's Disease imaging data show that incorporating spatial information can improve model fitness.

15.
J Pediatr ; 231: 55-60.e1, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33373672

RESUMEN

OBJECTIVE: To determine whether early polyethylene bag use with skin-to-skin care compared with skin-to skin care alone reduce hypothermia among infants born at term in resource-limited settings. STUDY DESIGN: Infants born at term in the tertiary referral center in Lusaka, Zambia, were randomized using sequentially numbered sealed opaque envelopes in 2 phases: after birth (phase 1) and at 1 hour after birth (phase 2) to either skin-to-skin care with polyethylene bags or skin-to-skin care alone. Infant and maternal temperatures were recorded at birth, 1 hour, and every 4 hours until discharge or 24 hours. RESULTS: We enrolled 423 infants from May 2017 to August 2017. The rate of moderate-severe hypothermia (temperature <36.0°C) at 1 hour was 72 of 208 (34.6%) in the skin-to-skin care with a polyethylene bag group compared with 101 of 213 (47.4%) in the skin-to-skin care alone group (relative risk, 0.71; 95% CI 0.56-0.90; P < .01; number needed to treat = 8). phase 1 treatment assignment significantly modified the effect of phase 2 treatment (P = .02 for interaction effect). Among infants randomized to skin-to-skin care with a polyethylene bag in phase 1, the risk of moderate-severe hypothermia was decreased in infants randomized to continue this intervention until discharge compared with infants randomized to skin-to-skin care alone. The rates of severe hypothermia, hyperthermia, and other adverse events did not differ significantly between groups. CONCLUSIONS: Low-cost polyethylene bags started after birth in combination with skin-to-skin care reduced moderate or severe hypothermia at 1 hour and at discharge among infants born at term in a resource-limited setting compared with skin-to-skin care alone. TRIAL REGISTRATION: ClinicalTrials.gov: NCT03141723.


Asunto(s)
Hipotermia/prevención & control , Método Madre-Canguro , Polietileno/uso terapéutico , Ropa de Protección , Terapia Combinada , Femenino , Humanos , Hipotermia/diagnóstico , Recién Nacido , Masculino , Resultado del Tratamiento
16.
Muscle Nerve ; 62(2): 261-266, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32369631

RESUMEN

INTRODUCTION: Quantitative Myasthenia Gravis (QMG) and Myasthenia Gravis Activities of Daily Living (MG-ADL) scales were compared using the data from the Thymectomy Trial in Non-Thymomatous Myasthenia Gravis Patients Receiving Prednisone Therapy (MGTX) study. METHODS: Correlation between QMG and MG-ADL raw and change-from-baseline scores was calculated every 3 months for 60 months based on treatment groups and minimal manifestation status (MMS). RESULTS: QMG and MG-ADL change-from-baseline scores correlated significantly, with increasing strength of correlation over time, in both treatment groups. QMG and MG-ADL raw scores correlated significantly in both treatment groups, with increasing correlation only in the prednisone-alone group. Correlation between raw scores was weaker in patients who were in MMS, demonstrating a "floor effect" on the MG-ADL scale. Raw QMG scores could be modeled assuming a normal distribution, whereas raw MG-ADL scores could not be modeled this way. DISCUSSION: The floor effect and skewed distribution of the MG-ADL measure should be taken into account in the design of myasthenia gravis clinical trials.


Asunto(s)
Actividades Cotidianas , Miastenia Gravis/fisiopatología , Evaluación de Resultado en la Atención de Salud , Terapia Combinada , Glucocorticoides/uso terapéutico , Humanos , Miastenia Gravis/terapia , Prednisona/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto , Timectomía
17.
Neurosurg Focus ; 48(4): E13, 2020 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-32234993

RESUMEN

OBJECTIVE: The goal of this study was to evaluate the predictive value and relative contribution of noninvasive presurgical functional imaging modalities based on the authors' institutional experience in pursuing seizure-free surgical outcomes in children with medically refractory epilepsy. METHODS: This was a retrospective, single-institution, observational cohort study of pediatric patients who underwent evaluation and surgical treatment for medically refractory partial epilepsy between December 2003 and June 2016. During this interval, 108 children with medically refractory partial epilepsy underwent evaluation for localization and resective epilepsy surgery. Different noninvasive functional imaging modalities, including ictal SPECT, FDG-PET, and magnetoencephalography-magnetic source imaging, were utilized to augment a standardized paradigm (electroencephalography/semiology, MRI, and neuropsychology findings) for localization. Outcomes were evaluated at a minimum of 2 years (mean 7.5 years) utilizing area under the receiver operating characteristic curve analysis. Localizing modalities and other clinical covariates were examined in relation to long-term surgical outcomes. RESULTS: There was variation in the contribution of each test, and no single presurgical workup modality could singularly and reliably predict a seizure-free outcome. However, concordance of presurgical modalities yielded a high predictive value. No difference in long-term outcomes between inconclusive (normal or diffusely abnormal) and abnormal focal MRI results were found. Long-term survival analyses revealed a statistically significant association between seizure freedom and patients with focal ictal EEG, early surgical intervention, and no history of generalized convulsions. CONCLUSIONS: Comprehensive preoperative evaluation utilizing multiple noninvasive functional imaging modalities is not redundant and can improve pediatric epilepsy surgical outcomes.


Asunto(s)
Epilepsia/diagnóstico por imagen , Epilepsia/cirugía , Procedimientos Neuroquirúrgicos , Convulsiones/diagnóstico por imagen , Convulsiones/cirugía , Adolescente , Adulto , Preescolar , Estudios de Cohortes , Electroencefalografía/métodos , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Procedimientos Neuroquirúrgicos/métodos , Estudios Retrospectivos
18.
Emerg Infect Dis ; 25(11): 2064-2073, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31625835

RESUMEN

West Nile Virus (WNV) can result in clinically severe neurologic disease. There is no treatment for WNV infection, but administration of anti-WNV polyclonal human antibody has demonstrated efficacy in animal models. We compared Omr-IgG-am, an immunoglobulin product with high titers of anti-WNV antibody, with intravenous immunoglobulin (IVIG) and normal saline to assess safety and efficacy in patients with WNV neuroinvasive disease as part of a phase I/II, randomized, double-blind, multicenter study in North America. During 2003-2006, a total of 62 hospitalized patients were randomized to receive Omr-IgG-am, standard IVIG, or normal saline (3:1:1). The primary endpoint was medication safety. Secondary endpoints were morbidity and mortality, measured using 4 standardized assessments of cognitive and functional status. The death rate in the study population was 12.9%. No significant differences were found between groups receiving Omr-IgG-am compared with IVIG or saline for either the safety or efficacy endpoints.


Asunto(s)
Enfermedades Virales del Sistema Nervioso Central/tratamiento farmacológico , Enfermedades Virales del Sistema Nervioso Central/virología , Inmunoglobulina G/uso terapéutico , Inmunoglobulinas Intravenosas/uso terapéutico , Fiebre del Nilo Occidental/tratamiento farmacológico , Fiebre del Nilo Occidental/virología , Virus del Nilo Occidental , Adulto , Anciano , Anticuerpos Neutralizantes/administración & dosificación , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/administración & dosificación , Anticuerpos Antivirales/inmunología , Enfermedades Virales del Sistema Nervioso Central/inmunología , Femenino , Humanos , Inmunoglobulina G/administración & dosificación , Inmunoglobulinas Intravenosas/administración & dosificación , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Fiebre del Nilo Occidental/inmunología , Virus del Nilo Occidental/inmunología
19.
N Engl J Med ; 375(6): 511-22, 2016 08 11.
Artículo en Inglés | MEDLINE | ID: mdl-27509100

RESUMEN

BACKGROUND: Thymectomy has been a mainstay in the treatment of myasthenia gravis, but there is no conclusive evidence of its benefit. We conducted a multicenter, randomized trial comparing thymectomy plus prednisone with prednisone alone. METHODS: We compared extended transsternal thymectomy plus alternate-day prednisone with alternate-day prednisone alone. Patients 18 to 65 years of age who had generalized nonthymomatous myasthenia gravis with a disease duration of less than 5 years were included if they had Myasthenia Gravis Foundation of America clinical class II to IV disease (on a scale from I to V, with higher classes indicating more severe disease) and elevated circulating concentrations of acetylcholine-receptor antibody. The primary outcomes were the time-weighted average Quantitative Myasthenia Gravis score (on a scale from 0 to 39, with higher scores indicating more severe disease) over a 3-year period, as assessed by means of blinded rating, and the time-weighted average required dose of prednisone over a 3-year period. RESULTS: A total of 126 patients underwent randomization between 2006 and 2012 at 36 sites. Patients who underwent thymectomy had a lower time-weighted average Quantitative Myasthenia Gravis score over a 3-year period than those who received prednisone alone (6.15 vs. 8.99, P<0.001); patients in the thymectomy group also had a lower average requirement for alternate-day prednisone (44 mg vs. 60 mg, P<0.001). Fewer patients in the thymectomy group than in the prednisone-only group required immunosuppression with azathioprine (17% vs. 48%, P<0.001) or were hospitalized for exacerbations (9% vs. 37%, P<0.001). The number of patients with treatment-associated complications did not differ significantly between groups (P=0.73), but patients in the thymectomy group had fewer treatment-associated symptoms related to immunosuppressive medications (P<0.001) and lower distress levels related to symptoms (P=0.003). CONCLUSIONS: Thymectomy improved clinical outcomes over a 3-year period in patients with nonthymomatous myasthenia gravis. (Funded by the National Institute of Neurological Disorders and Stroke and others; MGTX ClinicalTrials.gov number, NCT00294658.).


Asunto(s)
Glucocorticoides/administración & dosificación , Miastenia Gravis/tratamiento farmacológico , Miastenia Gravis/cirugía , Prednisona/administración & dosificación , Timectomía , Adolescente , Adulto , Anciano , Terapia Combinada , Femenino , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Miastenia Gravis/clasificación , Índice de Severidad de la Enfermedad , Método Simple Ciego , Resultado del Tratamiento , Adulto Joven
20.
Muscle Nerve ; 60(6): 700-706, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31478207

RESUMEN

INTRODUCTION: Labor-market participation is potentially very difficult for patients with refractory myasthenia gravis (MG). In this study, employment status and work absences are compared between refractory and nonrefractory MG. METHODS: Adults (aged 18-64 years, all diagnosed ≥2 years previously) were included if enrolled in the Myasthenia Gravis Foundation of America Patient Registry during July 2013 to February 2018. RESULTS: Seventy-six patients (9.2%) had refractory and 749 (90.8%) had nonrefractory disease; demographic data did not differ between groups. Relative to the nonrefractory group, the refractory group patients were more than twice as likely to work fewer hours per week (odds ratio [95% confidence interval]: currently employed, 2.777 [1.640-4.704]; employed over previous 6 months, 2.643 [1.595-4.380]), but those employed were not more likely to be absent from work. DISCUSSION: Because absence from the labor market adversely affects quality of life and personal finances, these findings reaffirm the considerable disease burden associated with refractory MG.


Asunto(s)
Empleo/estadística & datos numéricos , Miastenia Gravis/fisiopatología , Ausencia por Enfermedad/estadística & datos numéricos , Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Miastenia Gravis/terapia , Insuficiencia del Tratamiento , Desempleo/estadística & datos numéricos , Adulto Joven
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