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1.
Brain ; 147(4): 1247-1263, 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-37935051

RESUMEN

Missense variants in SCN3A encoding the voltage-gated sodium (Na+) channel α subunit Nav1.3 are associated with SCN3A-related neurodevelopmental disorder (SCN3A-NDD), a spectrum of disease that includes epilepsy and malformation of cortical development. How genetic variation in SCN3A leads to pathology remains unclear, as prior electrophysiological work on disease-associated variants has been performed exclusively in heterologous cell systems. To further investigate the mechanisms of SCN3A-NDD pathogenesis, we used CRISPR/Cas9 gene editing to modify a control human induced pluripotent stem cell (iPSC) line to express the recurrent de novo missense variant SCN3A c.2624T>C (p.Ile875Thr). With the established Ngn2 rapid induction protocol, we generated glutamatergic forebrain-like neurons (iNeurons), which we showed to express SCN3A mRNA and Nav1.3-mediated Na+ currents. We performed detailed whole-cell patch clamp recordings to determine the effect of the SCN3A-p.Ile875Thr variant on endogenous Na+ currents in, and intrinsic excitability of, human neurons. Compared to control iNeurons, variant-expressing iNeurons exhibit markedly increased slowly-inactivating/persistent Na+ current, abnormal firing patterns with paroxysmal bursting and plateau-like potentials with action potential failure, and a hyperpolarized voltage threshold for action potential generation. We then validated these findings using a separate iPSC line generated from a patient harbouring the SCN3A-p.Ile875Thr variant compared to a corresponding CRISPR-corrected isogenic control line. Finally, we found that application of the Nav1.3-selective blocker ICA-121431 normalizes action potential threshold and aberrant firing patterns in SCN3A-p.Ile1875Thr iNeurons; in contrast, consistent with action as a Na+ channel blocker, ICA-121431 decreases excitability of control iNeurons. Our findings demonstrate that iNeurons can model the effects of genetic variation in SCN3A yet reveal a complex relationship between gain-of-function at the level of the ion channel versus impact on neuronal excitability. Given the transient expression of SCN3A in the developing human nervous system, selective blockade or suppression of Nav1.3-containing Na+ channels could represent a therapeutic approach towards SCN3A-NDD.


Asunto(s)
Acetamidas , Encefalopatías , Células Madre Pluripotentes Inducidas , Tiazoles , Humanos , Potenciales de Acción , Canal de Sodio Activado por Voltaje NAV1.3/genética , Neuronas/fisiología , Sodio , Canales de Sodio/genética
2.
Genes Dev ; 31(9): 889-903, 2017 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-28546511

RESUMEN

A subset of long noncoding RNAs (lncRNAs) is spatially correlated with transcription factors (TFs) across the genome, but how these lncRNA-TF gene duplexes regulate tissue development and homeostasis is unclear. We identified a feedback loop within the NANCI (Nkx2.1-associated noncoding intergenic RNA)-Nkx2.1 gene duplex that is essential for buffering Nkx2.1 expression, lung epithelial cell identity, and tissue homeostasis. Within this locus, Nkx2.1 directly inhibits NANCI, while NANCI acts in cis to promote Nkx2.1 transcription. Although loss of NANCI alone does not adversely affect lung development, concurrent heterozygous mutations in both NANCI and Nkx2.1 leads to persistent Nkx2.1 deficiency and reprogramming of lung epithelial cells to a posterior endoderm fate. This disruption in the NANCI-Nkx2.1 gene duplex results in a defective perinatal innate immune response, tissue damage, and progressive degeneration of the adult lung. These data point to a mechanism in which lncRNAs act as rheostats within lncRNA-TF gene duplex loci that buffer TF expression, thereby maintaining tissue-specific cellular identity during development and postnatal homeostasis.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica , Homeostasis , Pulmón/crecimiento & desarrollo , Pulmón/fisiología , Proteínas Nucleares/metabolismo , ARN Largo no Codificante/metabolismo , Factores de Transcripción/genética , Animales , Células Epiteliales/inmunología , Células Epiteliales/metabolismo , Humanos , Inmunidad Celular , Pulmón/inmunología , Ratones , Proteínas Nucleares/genética , ARN Largo no Codificante/genética , Factor Nuclear Tiroideo 1 , Factores de Transcripción/metabolismo
3.
J Clin Immunol ; 44(4): 87, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38578402

RESUMEN

We present a case study of a young male with a history of 22q11.2 deletion syndrome (22qDS), diagnosed with systemic capillary leak syndrome (SCLS) who presented with acute onset of diffuse anasarca and sub-comatose obtundation. We hypothesized that his co-presentation of neurological sequelae might be due to blood-brain barrier (BBB) susceptibility conferred by the 22q11.2 deletion, a phenotype that we have previously identified in 22qDS. Using pre- and post-intravenous immunoglobulins (IVIG) patient serum, we studied circulating biomarkers of inflammation and assessed the potential susceptibility of the 22qDS BBB. We employed in vitro cultures of differentiated BBB-like endothelial cells derived from a 22qDS patient and a healthy control. We found evidence of peripheral inflammation and increased serum lipopolysaccharide (LPS) alongside endothelial cells in circulation. We report that the patient's serum significantly impairs barrier function of the 22qDS BBB compared to control. Only two other cases of pediatric SCLS with neurologic symptoms have been reported, and genetic risk factors have been suggested in both instances. As the third case to be reported, our findings are consistent with the hypothesis that genetic susceptibility of the BBB conferred by genes such as claudin-5 deleted in the 22q11.2 region promoted neurologic involvement during SCLS in this patient.


Asunto(s)
Síndrome de Fuga Capilar , Síndrome de DiGeorge , Humanos , Masculino , Niño , Síndrome de Fuga Capilar/diagnóstico , Barrera Hematoencefálica , Células Endoteliales , Permeabilidad , Inflamación
4.
Eur J Immunol ; 53(1): e2249840, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36337041

RESUMEN

Mice modeling the hemizygous deletion of chromosome 22q11.2 (22qMc) have been utilized to address various clinical phenotypes associated with the disease, including cardiac malformations, altered neural circuitry, and behavioral deficits. Yet, the status of the T cell compartment, an important clinical concern among 22q11.2 deletion syndrome (22qDS) patients, has not been addressed. While infancy and early childhood in 22qDS are associated with deficient T cell numbers and thymic hypoplasia, which can be severe in a small subset of patients, studies suggest normalization of the T cell counts by adulthood. We found that adult 22qMc do not exhibit thymic hypoplasia or altered thymic T cell development. Our findings that immune cell counts and inflammatory T cell activation are unaffected in 22qMc lend support to the hypothesis that human 22qDS immunodeficiencies are secondary to thymic hypoplasia, rather than intrinsic effects due to the deletion. Furthermore, the 22q11.2 deletion does not impact the differentiation capacity of T cells, nor their activity and response during inflammatory activation. Thus, 22qMc reflects the T cell compartment in adult 22qDS patients, and our findings suggest that 22qMc may serve as a novel model to address experimental and translational aspects of immunity in 22qDS.


Asunto(s)
Síndrome de DiGeorge , Síndromes de Inmunodeficiencia , Humanos , Preescolar , Adulto , Ratones , Animales , Síndrome de DiGeorge/genética , Síndrome de DiGeorge/complicaciones , Deleción Cromosómica , Timo , Síndromes de Inmunodeficiencia/genética , Linfocitos T
5.
Cancer ; 128(14): 2728-2735, 2022 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-35578919

RESUMEN

BACKGROUND: Black race is associated with worse outcome in patients with breast cancer. The distant relapse-free survival (DRFS) between Black and White women with localized breast cancer who participated in National Cancer Institute-sponsored clinical trial was evaluated. METHODS: Pooled data were analyzed from 8 National Surgical Adjuvant Breast and Bowel Project (NSABP) trials including 9702 women with localized breast cancer treated with adjuvant chemotherapy (AC, n = 7485) or neoadjuvant chemotherapy (NAC, n = 2217), who self-reported as Black (n = 1070) or White (n = 8632) race. The association between race and DRFS was analyzed using log-rank tests and multivariate Cox regression. RESULTS: After adjustment for covariates including age, tumor size, nodal status, body mass index and taxane use, and treatment (AC vs NAC), Black race was associated with an inferior DRFS in estrogen receptor-positive (ER+; hazard ratio [HR], 1.24; 95% CI, 1.05-1.46; P = .01), but not in ER- disease (HR, 0.97; 95% CI, 0.83-1.14; P = .73), and significant interaction between race and ER status was observed (P = .03). There was no racial disparity in DRFS among patients with pathologic complete response (pCR) (log-rank P = .8). For patients without pCR, Black race was associated with worse DRFS in ER+ (HR, 1.67; 95% CI, 1.14-2.45; P = .01), but not in ER- disease (HR, 0.91; 95% CI, 0.65-1.28; P = .59). CONCLUSIONS: Black race was associated with significantly inferior DRFS in ER+ localized breast cancer treated with AC or NAC, but not in ER- disease. In the NAC group, racial disparity was also observed in patients with residual ER+ breast cancer at surgery, but not in those who had pCR. LAY SUMMARY: Black women with breast cancer have worse outcomes compared with White women. We investigated if this held true in the context of clinical trials that provide controlled treatment setting. Black women with cancer expressing estrogen receptors (ERs) had worse outcome than White women. If breast cancers did not express ERs, there was no racial disparity in outcome. We also observed racial disparity in women who received chemotherapy before their cancer was removed, but only if they had cancer expressing ERs and residual disease on completion of treatment. If the cancer disappeared with presurgical chemotherapy, there was no racial disparity.


Asunto(s)
Neoplasias de la Mama , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/cirugía , Quimioterapia Adyuvante , Femenino , Humanos , Terapia Neoadyuvante , Recurrencia Local de Neoplasia/tratamiento farmacológico , Receptores de Estrógenos/análisis
6.
Dev Neurosci ; 44(4-5): 246-265, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35279653

RESUMEN

Intrauterine hypoxia is a common cause of brain injury in children resulting in a broad spectrum of long-term neurodevelopmental sequela, including life-long disabilities that can occur even in the absence of severe neuroanatomic damage. Postnatal hypoxia-ischemia rodent models are commonly used to understand the effects of ischemia and transient hypoxia on the developing brain. Postnatal models, however, have some limitations. First, they do not test the impact of placental pathologies on outcomes from hypoxia. Second, they primarily recapitulate severe injury because they provoke substantial cell death, which is not seen in children with mild hypoxic injury. Lastly, they do not model preterm hypoxic injury. Prenatal models of hypoxia in mice may allow us to address some of these limitations to expand our understanding of developmental brain injury. The published rodent models of prenatal hypoxia employ multiple days of hypoxic exposure or complicated surgical procedures, making these models challenging to perform consistently in mice. Furthermore, large animal models suggest that transient prenatal hypoxia without ischemia is sufficient to lead to significant functional impairment to the developing brain. However, these large animal studies are resource-intensive and not readily amenable to mechanistic molecular studies. Therefore, here we characterized the effect of late gestation (embryonic day 17.5) transient prenatal hypoxia (5% inspired oxygen) on long-term anatomical and neurodevelopmental outcomes in mice. Late gestation transient prenatal hypoxia increased hypoxia-inducible factor 1 alpha protein levels (a marker of hypoxic exposure) in the fetal brain. Hypoxia exposure predisposed animals to decreased weight at postnatal day 2, which normalized by day 8. However, hypoxia did not affect gestational age at birth, litter size at birth, or pup survival. No differences in fetal brain cell death or long-term gray or white matter changes resulted from hypoxia. Animals exposed to prenatal hypoxia did have several long-term functional consequences, including sex-dichotomous changes. Hypoxia exposure was associated with a decreased seizure threshold and abnormalities in hindlimb strength and repetitive behaviors in males and females. Males exposed to hypoxia had increased anxiety-related deficits, whereas females had deficits in social interaction. Neither sex developed any motor or visual learning deficits. This study demonstrates that late gestation transient prenatal hypoxia in mice is a simple, clinically relevant paradigm for studying putative environmental and genetic modulators of the long-term effects of hypoxia on the developing brain.


Asunto(s)
Lesiones Encefálicas , Placenta , Animales , Animales Recién Nacidos , Encéfalo/patología , Lesiones Encefálicas/patología , Modelos Animales de Enfermedad , Femenino , Hipoxia , Masculino , Ratones , Embarazo , Convulsiones
7.
PLoS Comput Biol ; 17(11): e1009594, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34762648

RESUMEN

The growing number of next-generation sequencing (NGS) data presents a unique opportunity to study the combined impact of mitochondrial and nuclear-encoded genetic variation in complex disease. Mitochondrial DNA variants and in particular, heteroplasmic variants, are critical for determining human disease severity. While there are approaches for obtaining mitochondrial DNA variants from NGS data, these software do not account for the unique characteristics of mitochondrial genetics and can be inaccurate even for homoplasmic variants. We introduce MitoScape, a novel, big-data, software for extracting mitochondrial DNA sequences from NGS. MitoScape adopts a novel departure from other algorithms by using machine learning to model the unique characteristics of mitochondrial genetics. We also employ a novel approach of using rho-zero (mitochondrial DNA-depleted) data to model nuclear-encoded mitochondrial sequences. We showed that MitoScape produces accurate heteroplasmy estimates using gold-standard mitochondrial DNA data. We provide a comprehensive comparison of the most common tools for obtaining mtDNA variants from NGS and showed that MitoScape had superior performance to compared tools in every statistically category we compared, including false positives and false negatives. By applying MitoScape to common disease examples, we illustrate how MitoScape facilitates important heteroplasmy-disease association discoveries by expanding upon a reported association between hypertrophic cardiomyopathy and mitochondrial haplogroup T in men (adjusted p-value = 0.003). The improved accuracy of mitochondrial DNA variants produced by MitoScape will be instrumental in diagnosing disease in the context of personalized medicine and clinical diagnostics.


Asunto(s)
Macrodatos , ADN Mitocondrial/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Aprendizaje Automático , Genes Mitocondriales , Humanos
8.
Brain ; 144(5): 1351-1360, 2021 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-33876226

RESUMEN

Neuroimmune dysregulation is implicated in neuropsychiatric disorders including schizophrenia. As the blood-brain barrier is the immunological interface between the brain and the periphery, we investigated whether this vascular phenotype is intrinsically compromised in the most common genetic risk factor for schizophrenia, the 22q11.2 deletion syndrome (22qDS). Blood-brain barrier like endothelium differentiated from human 22qDS+schizophrenia-induced pluripotent stem cells exhibited impaired barrier integrity, a phenotype substantiated in a mouse model of 22qDS. The proinflammatory intercellular adhesion molecule-1 was upregulated in 22qDS+schizophrenia-induced blood-brain barrier and in 22qDS mice, indicating compromise of the blood-brain barrier immune privilege. This immune imbalance resulted in increased migration/activation of leucocytes crossing the 22qDS+schizophrenia blood-brain barrier. We also found heightened astrocyte activation in murine 22qDS, suggesting that the blood-brain barrier promotes astrocyte-mediated neuroinflammation. Finally, we substantiated these findings in post-mortem 22qDS brain tissue. Overall, the barrier-promoting and immune privilege properties of the 22qDS blood-brain barrier are compromised, and this might increase the risk for neuropsychiatric disease.


Asunto(s)
Síndrome de Deleción 22q11/patología , Barrera Hematoencefálica/patología , Síndrome de Deleción 22q11/inmunología , Animales , Astrocitos/metabolismo , Humanos , Privilegio Inmunológico/fisiología , Inflamación/metabolismo , Ratones
9.
Clin Trials ; 19(2): 127-136, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34991349

RESUMEN

Dr. Bernard Fisher (1918-2019) was an early proponent of evidence-based medicine using the mechanism of prospective, multicenter, randomized clinical trials to test biological and clinical hypotheses. In this article, I trace how his early scientific work in striving to understand the nature of cancer metastasis through animal experiments led to a new, testable, clinical hypothesis: that surgery to remove only the tumor and a small amount of tissue around it was as effective as the more disfiguring operations that were then the standard treatment. Fisher's work with the National Surgical Adjuvant Breast and Bowel Project (NSABP) using large, randomized clinical trials to demonstrate the veracity of this hypothesis led to a new paradigm in which the emphasis was placed on how systemic therapies used at an early stage of disease could effectively eradicate breast cancer for many patients. This new therapeutic approach led to the successful development of new treatments, many of which are widely used today. Ultimately, the new paradigm led to successfully preventing breast cancer in women who were at high risk for the disease but who had not yet been diagnosed with the disease. Throughout his entire career, Fisher championed the use of large prospective, randomized clinical trials despite criticism from many in the medical community who strongly criticized his use of randomization as a mechanism for testing clinical hypotheses. The approach he and the NSABP employed is still considered to be the highest standard of evidence in conducting clinical studies.


Asunto(s)
Neoplasias de la Mama , Neoplasias de la Mama/tratamiento farmacológico , Femenino , Humanos , Estudios Prospectivos , Ensayos Clínicos Controlados Aleatorios como Asunto
10.
Stem Cells ; 38(11): 1375-1386, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32638460

RESUMEN

The cerebral cortex functions by the complex interactions of intrinsic and extrinsic neuronal activities, glial actions, and the effects of humoral factors. The intrinsic neuronal influences are mediated by two major subclasses: excitatory glutamatergic neurons that generally have axonal projections extending beyond the neuron's locality and inhibitory GABAergic neurons that generally project locally. These interneurons can be grouped based on morphological, neurochemical, electrophysiological, axonal targeting, and circuit influence characteristics. Cortical interneurons (CIns) can also be grouped based on their origins within the subcortical telencephalon. Interneuron subtypes, of which a dozen or more are thought to exist, are characterized by combinations of these subgrouping features. Due to their well-documented relevance to the causes of and treatments for neuropsychiatric disorders, and to their remarkable capacity to migrate extensively following transplantation, there has been tremendous interest in generating cortical GABAergic interneurons from human pluripotent stem cells. In this concise review, we discuss recent progress in understanding how interneuron subtypes are generated in vivo, and how that progress is being applied to the generation of rodent and human CIns in vitro. In addition, we will discuss approaches for the rigorous designation of interneuron subgroups or subtypes in transplantation studies, and challenges to this field, including the protracted maturation of human interneurons.


Asunto(s)
Corteza Cerebral/fisiología , Neuronas GABAérgicas/metabolismo , Interneuronas/metabolismo , Células-Madre Neurales/metabolismo , Animales , Diferenciación Celular , Humanos , Ratones
11.
Biometrics ; 75(4): 1299-1309, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31022303

RESUMEN

Predicting clinical variables from whole-brain neuroimages is a high-dimensional problem that can potentially benefit from feature selection or extraction. Penalized regression is a popular embedded feature selection method for high-dimensional data. For neuroimaging applications, spatial regularization using the ℓ1 or ℓ2 norm of the image gradient has shown good performance, yielding smooth solutions in spatially contiguous brain regions. Enormous resources have been devoted to establishing structural and functional brain connectivity networks that can be used to define spatially distributed yet related groups of voxels. We propose using the fused sparse group lasso (FSGL) penalty to encourage structured, sparse, and interpretable solutions by incorporating prior information about spatial and group structure among voxels. We present optimization steps for FSGL penalized regression using the alternating direction method of multipliers algorithm. With simulation studies and in application to real functional magnetic resonance imaging data from the Autism Brain Imaging Data Exchange, we demonstrate conditions under which fusion and group penalty terms together outperform either of them alone.


Asunto(s)
Mapeo Encefálico/métodos , Red Nerviosa , Neuroimagen/métodos , Algoritmos , Simulación por Computador , Conjuntos de Datos como Asunto , Humanos , Imagen por Resonancia Magnética/métodos , Modelos Estadísticos
12.
Am J Geriatr Psychiatry ; 27(10): 1035-1045, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31047790

RESUMEN

OBJECTIVE: Older adults with knee osteoarthritis (OA) and comorbid subsyndromal depressive symptoms are at elevated risk for incidental major depression or anxiety disorders. Using an indicated prevention paradigm, the authors conducted a sequenced multiple assignment randomized trial (SMART) to: 1) evaluate the effect of cognitive behavioral therapy (CBT) and physical therapy (PT), together with the temporal ordering of these interventions, on patient-reported global impression of change (P-GIC), mood, anxiety, and pain; and 2) compare the strategies' impact on incidence of common psychiatric disorders over 12-months. METHODS: This intervention development trial compared four adaptive strategies delivered in two stages (each up to 8 weeks), contrasted with enhanced usual care (EUC). The strategies were CBT followed by an increased dose of CBT (CBT-CBT), CBT followed by PT (CBT-PT), PT followed by an increased dose of PT (PT-PT), and PT followed by CBT (PT-CBT). Participants (n = 99) were aged 60 years and older and met clinical criteria for knee OA and subthreshold depression. Response was defined as at least "much better" on the P-GIC. Participants were assessed quarterly for 12 months for incidence of psychiatric disorders. RESULTS: Stage 1 response was higher for PT (47.5%) compared to CBT (20.5%). Non-responders receiving an additional dose of the same intervention experienced a response rate of 73%, higher than for switching to a different intervention. All strategies were superior to EUC (5%). Although not powered to detect effects on disorders, neither intervention strategy nor response status affected 12-month incidence of depression and anxiety disorders. CONCLUSION: As response rates were similar for PT-PT and CBT-CBT, it may be dose and not type of these interventions that are necessary for clinical benefit. For non-responders, this finding may guide providers to stay the clinical course for up to 12 weeks before switching. These results support future trials of SMART designs in late-life depression prevention.


Asunto(s)
Trastornos de Ansiedad/prevención & control , Terapia Cognitivo-Conductual/métodos , Trastorno Depresivo Mayor/prevención & control , Osteoartritis de la Rodilla/psicología , Medición de Resultados Informados por el Paciente , Anciano , Comorbilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dolor/psicología , Escalas de Valoración Psiquiátrica , Índice de Severidad de la Enfermedad
13.
Am J Geriatr Psychiatry ; 27(6): 619-624, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30795944

RESUMEN

BACKGROUND: Interventions to prevent depression in older adults have mainly focused on young-old ambulatory adults, not on the old-old with disabilities who receive supportive services in their homes. OBJECTIVE: The Depression Agency-Based Collaborative (Dep-ABC) is a single-blind pilot randomized controlled trial assessing the effect of an intervention-development strategy using problem-solving therapy (PST) on the risk of common mental health disorders in this vulnerable population. METHODS: The intervention involved six to eight sessions of PST over 12 weeks. Participants were followed up to 12 months postintervention. RESULTS: Dep-ABC randomized 104 participants-68.4% of eligible and 17.5% of all older adults screened. The proportion of participants with incident major depressive disorder or generalized anxiety disorder was 11.4% in PST and 14.3% in the enhanced usual care control arm. A test of the interaction between time and intervention for anxiety symptoms favored the PST arm (p = 0.04). CONCLUSION: PST did not lower the risk of incident common mental illness but did lower anxiety symptom burden. Apart from low power, the effects of PST may have been blunted by referral for medical and aging services in the enhanced usual care group.


Asunto(s)
Trastornos de Ansiedad/prevención & control , Trastorno Depresivo Mayor/epidemiología , Solución de Problemas , Psicoterapia/métodos , Anciano , Anciano de 80 o más Años , Trastornos de Ansiedad/epidemiología , Trastorno Depresivo Mayor/prevención & control , Femenino , Servicios de Atención de Salud a Domicilio , Humanos , Masculino , Persona de Mediana Edad , Método Simple Ciego , Resultado del Tratamiento
14.
Stat Med ; 38(3): 301-314, 2019 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-30264471

RESUMEN

A strategy for early-stage breast cancer trials in recent years consists of a neoadjuvant trial with pathological complete response (pCR) at time of surgery as the efficacy endpoint, followed by the collection of long-term data to show efficacy in survival. To calculate an appropriate sample size to detect a survival difference based upon pCR data, it is necessary to relate the effect size in pCR with the effect size in survival. Here, we propose an exponential mixture model for survival time with parameters for the neoadjuvant pCR rates and an estimated benefit of achieving pCR to determine the treatment effect size. Through simulation studies, we demonstrated how to estimate the empirical power for detecting the survival efficacy under a parameter setting. We also showed a more efficient way to estimate the power for detecting the survival efficacy through estimated average hazard ratios and the Schoenfeld formula. Our method can be used to power future confirmatory adjuvant trials based on the preliminary data obtained from the neoadjuvant component.


Asunto(s)
Interpretación Estadística de Datos , Determinación de Punto Final/métodos , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Análisis de Supervivencia , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/cirugía , Neoplasias de la Mama/terapia , Terapia Combinada , Femenino , Humanos , Modelos Estadísticos , Terapia Neoadyuvante/mortalidad , Terapia Neoadyuvante/estadística & datos numéricos , Modelos de Riesgos Proporcionales , Factores de Tiempo
15.
Am J Psychother ; 72(4): 88-94, 2019 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-31813228

RESUMEN

OBJECTIVE: As a sequel to the Depression in Later Life trial of lay counselor-delivered problem-solving therapy for depression prevention among older adults in Goa, India, this qualitative study aimed to explore participant experiences to illuminate the reasons for the trial's positive findings and implications for further efforts at depression prevention in low-resource settings. METHODS: In-depth interviews were conducted with 19 participants (21% of those randomly assigned to the original intervention). Two independent raters coded the data and organized narratives according to broad themes. RESULTS: Most participants valued their relationship with the lay counselor, learned self-care strategies to cope with illnesses, and increased engagement in pleasurable social and physical activities. Some participants reported needing assistance with managing financial strain and family conflicts. CONCLUSIONS: The lay-counselor-delivered intervention was well received. The relationship with the counselor and behavioral activation toward better self-care and more-pleasurable activities may have been keys to the intervention's success.


Asunto(s)
Depresión/psicología , Depresión/terapia , Psicoterapia , Anciano , Trastorno Depresivo/psicología , Trastorno Depresivo/terapia , Femenino , Humanos , India , Masculino , Investigación Cualitativa
16.
Am J Epidemiol ; 187(7): 1520-1529, 2018 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-29394305

RESUMEN

Type 1 diabetes (T1D) is associated with increased risk of cardiovascular disease (CVD), but hyperglycemia (measured by hemoglobin A1c (HbA1c) level), which characterizes T1D, has itself been an inconsistent predictor of CVD incidence. However, only baseline HbA1c or a summary measure (e.g., mean level over follow-up) is usually analyzed. Joint models allow simultaneous modeling of repeatedly measured longitudinal covariates, using random effects, and time-to-event data. We evaluated data from the Pittsburgh Epidemiology of Diabetes Complications Study, an ongoing prospective cohort study of childhood-onset T1D that has followed participants since 1986-1988 and has repeatedly found little association between baseline HbA1c or mean follow-up HbA1c and coronary artery disease incidence. Of 561 participants without CVD at baseline, 263 (46.9%) developed CVD over a period of 25 years (1986-2014). In joint models, each 1% unit increase in HbA1c trajectory was associated with a 1.26-fold increased risk of CVD (95% confidence interval: 1.07, 1.45), after adjustment for baseline levels of other CVD risk factors, and a 1.13-fold increased risk (95% confidence interval: 0.99, 1.32) after adjustment for updated mean levels of other CVD risk factors. These findings, which support the need for good glycemic control to prevent CVD in persons with T1D, underscore the importance of utilizing methods incorporating within-subject variation over time when analyzing and interpreting longitudinal cohort study data.


Asunto(s)
Enfermedades Cardiovasculares/epidemiología , Diabetes Mellitus Tipo 1/complicaciones , Hemoglobina Glucada/análisis , Modelos Estadísticos , Factores de Tiempo , Adulto , Enfermedades Cardiovasculares/etiología , Diabetes Mellitus Tipo 1/sangre , Femenino , Humanos , Incidencia , Estudios Longitudinales , Masculino , Pennsylvania/epidemiología , Estudios Prospectivos , Factores de Riesgo
17.
Cancer ; 124(14): 2923-2930, 2018 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-29723396

RESUMEN

BACKGROUND: Several studies have reported a high risk of local disease recurrence (LR) and locoregional disease recurrence (LRR) in patients with breast cancer after neoadjuvant chemotherapy (NCT) and breast-conserving therapy (BCT). The objective of the current study was to identify potential risk factors for LR and LRR after NCT and BCT. METHODS: Individual patient data sets from 9 studies were pooled. The outcomes of interest were the occurrence of LR and/or LRR. A 1-stage meta-analytic approach was used. Cox proportional hazards regression models were applied to identify factors that were predictive of LR and LRR, respectively. RESULTS: A total of 9 studies (4125 patients) provided their data sets. The 10-year LR rate was 6.5%, whereas the 10-year LRR rate was 10.3%. Four factors were found to be associated with a higher risk of LR: 1) estrogen receptor-negative disease; 2) cN + disease; 3) a lack of pathologic complete response in axilla (pN0); and 4) pN2 to pN3 disease. The predictive score for LR determined 3 risk groups: a low-risk, intermediate-risk, and high-risk group with 10-year LR rates of 4.0%, 7.9%, and 20.4%, respectively. Two additional factors were found to be associated with an increased risk of LRR: cT3 to cT4 disease and a lack of pathologic complete response in the breast. The predictive score for LRR determined 3 risk groups; a low-risk, intermediate-risk, and high-risk group with 10-year LRR rates of 3.2%, 10.1%, and 24.1%, respectively. CONCLUSIONS: BCT after NCT appears to be an oncologically safe procedure for a large percentage of patients with breast cancer. Two easy-to-use clinical scores were developed that can help clinicians to identify patients at higher risk of LR and LRR after NCT and BCT and individualize the postoperative treatment plan and follow-up. Cancer 2018;124:2923-30. © 2018 American Cancer Society.


Asunto(s)
Neoplasias de la Mama/terapia , Mastectomía Segmentaria , Recurrencia Local de Neoplasia/epidemiología , Protocolos de Quimioterapia Combinada Antineoplásica , Axila , Mama/patología , Mama/cirugía , Neoplasias de la Mama/patología , Femenino , Humanos , Incidencia , Metástasis Linfática/patología , Terapia Neoadyuvante/métodos , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/prevención & control , Estadificación de Neoplasias , Receptores de Estrógenos/metabolismo , Factores de Riesgo , Ganglio Linfático Centinela/patología , Resultado del Tratamiento
18.
Development ; 142(7): 1267-78, 2015 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-25804737

RESUMEN

Medial ganglionic eminence (MGE)-derived GABAergic cortical interneurons (cINs) consist of multiple subtypes that are involved in many cortical functions. They also have a remarkable capacity to migrate, survive and integrate into cortical circuitry after transplantation into postnatal cortex. These features have engendered considerable interest in generating distinct subgroups of interneurons from pluripotent stem cells (PSCs) for the study of interneuron fate and function, and for the development of cell-based therapies. Although advances have been made, the capacity to generate highly enriched pools of subgroup fate-committed interneuron progenitors from PSCs has remained elusive. Previous studies have suggested that the two main MGE-derived interneuron subgroups--those expressing somatostatin (SST) and those expressing parvalbumin (PV)--are specified in the MGE from Nkx2.1-expressing progenitors at higher or lower levels of sonic hedgehog (Shh) signaling, respectively. To further explore the role of Shh and other factors in cIN fate determination, we generated a reporter line such that Nkx2.1-expressing progenitors express mCherry and postmitotic Lhx6-expressing MGE-derived interneurons express GFP. Manipulations of Shh exposure and time in culture influenced the subgroup fates of ESC-derived interneurons. Exposure to higher Shh levels, and collecting GFP-expressing precursors at 12 days in culture, resulted in the strongest enrichment for SST interneurons over those expressing PV, whereas the strongest enrichment for PV interneurons was produced by lower Shh and by collecting mCherry-expressing cells after 17 days in culture. These findings confirm that fate determination of cIN subgroups is crucially influenced by Shh signaling, and provide a system for the further study of interneuron fate and function.


Asunto(s)
Linaje de la Célula , Células Madre Embrionarias/citología , Proteínas Hedgehog/metabolismo , Interneuronas/metabolismo , Parvalbúminas/metabolismo , Transducción de Señal , Somatostatina/metabolismo , Potenciales de Acción , Animales , Tipificación del Cuerpo , Línea Celular , Separación Celular , Corteza Cerebral/citología , Células Madre Embrionarias/metabolismo , Neuronas GABAérgicas/metabolismo , Genes Reporteros , Proteínas Fluorescentes Verdes/metabolismo , Eminencia Media/citología , Ratones , Mitosis , Trasplante de Células Madre , Telencéfalo/embriología , Telencéfalo/metabolismo , Factores de Tiempo
19.
Nat Rev Neurosci ; 14(3): 202-16, 2013 03.
Artículo en Inglés | MEDLINE | ID: mdl-23385869

RESUMEN

A systematic classification and accepted nomenclature of neuron types is much needed but is currently lacking. This article describes a possible taxonomical solution for classifying GABAergic interneurons of the cerebral cortex based on a novel, web-based interactive system that allows experts to classify neurons with pre-determined criteria. Using Bayesian analysis and clustering algorithms on the resulting data, we investigated the suitability of several anatomical terms and neuron names for cortical GABAergic interneurons. Moreover, we show that supervised classification models could automatically categorize interneurons in agreement with experts' assignments. These results demonstrate a practical and objective approach to the naming, characterization and classification of neurons based on community consensus.


Asunto(s)
Algoritmos , Corteza Cerebral/citología , Interneuronas/clasificación , Interneuronas/citología , Terminología como Asunto , Ácido gamma-Aminobutírico/metabolismo , Animales , Teorema de Bayes , Corteza Cerebral/metabolismo , Análisis por Conglomerados , Humanos , Interneuronas/metabolismo
20.
Neurobiol Dis ; 103: 174-183, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28433741

RESUMEN

The zinc-finger SWIM domain-containing protein 6 (ZSWIM6) is a protein of unknown function that has been associated with schizophrenia and limited educational attainment by three independent genome-wide association studies. Additionally, a putatively causal point mutation in ZSWIM6 has been identified in several cases of acromelic frontonasal dysostosis with severe intellectual disability. Despite the growing number of studies implicating ZSWIM6 as an important regulator of brain development, its role in this process has never been examined. Here, we report the generation of Zswim6 knockout mice and provide a detailed anatomical and behavioral characterization of the resulting phenotype. We show that Zswim6 is initially expressed widely during embryonic brain development but becomes restricted to the striatum postnatally. Loss of Zswim6 causes a reduction in striatal volume and changes in medium spiny neuron morphology. These changes are associated with alterations in motor control, including hyperactivity, impaired rotarod performance, repetitive movements, and behavioral hyperresponsiveness to amphetamine. Together, our results show that Zswim6 is indispensable to normal brain function and support the notion that Zswim6 might serve as an important contributor to the pathogenesis of schizophrenia and other neurodevelopmental disorders.


Asunto(s)
Cuerpo Estriado/metabolismo , Cuerpo Estriado/patología , Proteínas de Unión al ADN/deficiencia , Hipercinesia/metabolismo , Hipercinesia/patología , Animales , Cuerpo Estriado/crecimiento & desarrollo , Proteínas de Unión al ADN/genética , Hipercinesia/genética , Locomoción/fisiología , Ratones , Ratones de la Cepa 129 , Ratones Endogámicos C57BL , Ratones Noqueados , Trastornos del Neurodesarrollo/genética , Trastornos del Neurodesarrollo/metabolismo , Trastornos del Neurodesarrollo/patología
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