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1.
Clin J Sport Med ; 34(1): 61-68, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37285595

RESUMEN

OBJECTIVE: To investigate the link between dysfunction of the blood-brain barrier (BBB) and exposure to head impacts in concussed football athletes. DESIGN: This was a prospective, observational pilot study. SETTING: Canadian university football. PARTICIPANTS: The study population consisted of 60 university football players, aged 18 to 25. Athletes who sustained a clinically diagnosed concussion over the course of a single football season were invited to undergo an assessment of BBB leakage. INDEPENDENT VARIABLES: Head impacts detected using impact-sensing helmets were the measured variables. MAIN OUTCOME MEASURES: Clinical diagnosis of concussion and BBB leakage assessed using dynamic contrast-enhanced MRI (DCE-MRI) within 1 week of concussion were the outcome measures. RESULTS: Eight athletes were diagnosed with a concussion throughout the season. These athletes sustained a significantly higher number of head impacts than nonconcussed athletes. Athletes playing in the defensive back position were significantly more likely to sustain a concussion than remain concussion free. Five of the concussed athletes underwent an assessment of BBB leakage. Logistic regression analysis indicated that region-specific BBB leakage in these 5 athletes was best predicted by impacts sustained in all games and practices leading up to the concussion-as opposed to the last preconcussion impact or the impacts sustained during the game when concussion occurred. CONCLUSIONS: These preliminary findings raise the potential for the hypothesis that repeated exposure to head impacts may contribute to the development of BBB pathology. Further research is needed to validate this hypothesis and to test whether BBB pathology plays a role in the sequela of repeated head trauma.


Asunto(s)
Conmoción Encefálica , Fútbol Americano , Humanos , Barrera Hematoencefálica/lesiones , Conmoción Encefálica/diagnóstico , Canadá , Fútbol Americano/lesiones , Estudios Prospectivos , Universidades
2.
Spine Deform ; 11(3): 733-738, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36689054

RESUMEN

BACKGROUND: Clinically significant proximal junctional kyphosis (PJK) occurs in 20% of children with scoliosis treated with posterior distraction-based growth-friendly surgery. In an effort to identify modifiable risk factors, it has been theorized biomechanically that low radius of curvature (ROC) implants (i.e., more curved rods) may increase post-operative thoracic kyphosis, and thus may pose a higher risk of developing PJK. We sought to test the hypothesis that early onset scoliosis (EOS) patients treated with low ROC distraction-based implants will have a greater risk of developing clinically significant PJK as compared to those treated with high ROC (straighter) implants. METHODS: We conducted a retrospective review of prospectively collected data obtained from a multi-centre EOS database on children treated with rib-based distraction with a minimum 2-year follow-up. Variables of interest included: implant ROC at index (220 mm or 500 mm), participant age, pre-operative scoliosis, pre-operative kyphosis, and scoliosis etiology. PJK was defined as clinically significant if revision surgery with a superior extension of the upper instrumented vertebrae was performed. RESULTS: In 148 participants with scoliosis, there was a higher risk of clinically significant PJK with low ROC (more curved) rods (OR: 2.6 (95% CI 1.09-5.99), χ2 (1, n = 148) = 4.8, p = 0.03). Participants had a mean pre-operative age of 5.3 years (4.6y 220 mm vs 6.2y 500 mm, p = 0.002). A logistic regression model was created with age as a confounding variable, but it was determined to be not significant (p = 0.6). Scoliosis etiologies included 52 neuromuscular, 52 congenital, 27 idiopathic, 17 syndromic with no significant differences in PJK risk between etiologies (p = 0.07). Overall, participants had pre-op scoliosis of 69° (67° 220 mm vs 72° 500 mm, p = 0.2), and kyphosis of 48° (45° 220 mm vs 51° 500 mm, p = 0.1). The change in thoracic kyphosis pre-operatively to final follow-up (mean 4.0 ± 0.2 years) was higher in participants treated with 220 mm implants compared to 500 mm implants (220 mm: 7.5 ± 2.6° vs 500 mm: - 4.0 ± 3.0°, p = 0.004). CONCLUSIONS: Use of low ROC (more curved) posterior distraction implants is associated with a significantly greater increase in thoracic kyphosis which likely led to a higher risk of developing clinically significant PJK in participants with EOS. LEVEL OF EVIDENCE: Level III - retrospective comparative study.


Asunto(s)
Cifosis , Escoliosis , Niño , Humanos , Preescolar , Escoliosis/cirugía , Escoliosis/complicaciones , Estudios Retrospectivos , Radio (Anatomía) , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Cifosis/cirugía , Cifosis/complicaciones , Costillas
3.
Brain ; 145(6): 2049-2063, 2022 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-34927674

RESUMEN

The mechanisms underlying the complications of mild traumatic brain injury, including post-concussion syndrome, post-impact catastrophic death, and delayed neurodegeneration remain poorly understood. This limited pathophysiological understanding has hindered the development of diagnostic and prognostic biomarkers and has prevented the advancement of treatments for the sequelae of mild traumatic brain injury. We aimed to characterize the early electrophysiological and neurovascular alterations following repetitive mild traumatic brain injury and sought to identify new targets for the diagnosis and treatment of individuals at risk of severe post-impact complications. We combined behavioural, electrophysiological, molecular, and neuroimaging techniques in a rodent model of repetitive mild traumatic brain injury. In humans, we used dynamic contrast-enhanced MRI to quantify blood-brain barrier dysfunction after exposure to sport-related concussive mild traumatic brain injury. Rats could clearly be classified based on their susceptibility to neurological complications, including life-threatening outcomes, following repetitive injury. Susceptible animals showed greater neurological complications and had higher levels of blood-brain barrier dysfunction, transforming growth factor ß (TGFß) signalling, and neuroinflammation compared to resilient animals. Cortical spreading depolarizations were the most common electrophysiological events immediately following mild traumatic brain injury and were associated with longer recovery from impact. Triggering cortical spreading depolarizations in mild traumatic brain injured rats (but not in controls) induced blood-brain barrier dysfunction. Treatment with a selective TGFß receptor inhibitor prevented blood-brain barrier opening and reduced injury complications. Consistent with the rodent model, blood-brain barrier dysfunction was found in a subset of human athletes following concussive mild traumatic brain injury. We provide evidence that cortical spreading depolarization, blood-brain barrier dysfunction, and pro-inflammatory TGFß signalling are associated with severe, potentially life-threatening outcomes following repetitive mild traumatic brain injury. Diagnostic-coupled targeting of TGFß signalling may be a novel strategy in treating mild traumatic brain injury.


Asunto(s)
Conmoción Encefálica , Animales , Barrera Hematoencefálica/metabolismo , Encéfalo/metabolismo , Conmoción Encefálica/etiología , Humanos , Neuroimagen , Ratas , Factor de Crecimiento Transformador beta/metabolismo
4.
Int J Mol Sci ; 22(21)2021 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-34769073

RESUMEN

Traumatic brain injury (TBI) is the leading cause of death in young individuals, and is a major health concern that often leads to long-lasting complications. However, the electrophysiological events that occur immediately after traumatic brain injury, and may underlie impact outcomes, have not been fully elucidated. To investigate the electrophysiological events that immediately follow traumatic brain injury, a weight-drop model of traumatic brain injury was used in rats pre-implanted with epidural and intracerebral electrodes. Electrophysiological (near-direct current) recordings and simultaneous alternating current recordings of brain activity were started within seconds following impact. Cortical spreading depolarization (SD) and SD-induced spreading depression occurred in approximately 50% of mild and severe impacts. SD was recorded within three minutes after injury in either one or both brain hemispheres. Electrographic seizures were rare. While both TBI- and electrically induced SDs resulted in elevated oxidative stress, TBI-exposed brains showed a reduced antioxidant defense. In severe TBI, brainstem SD could be recorded in addition to cortical SD, but this did not lead to the death of the animals. Severe impact, however, led to immediate death in 24% of animals, and was electrocorticographically characterized by non-spreading depression (NSD) of activity followed by terminal SD in both cortex and brainstem.


Asunto(s)
Lesiones Traumáticas del Encéfalo/fisiopatología , Tronco Encefálico/fisiopatología , Depresión de Propagación Cortical , Animales , Lesiones Traumáticas del Encéfalo/metabolismo , Tronco Encefálico/metabolismo , Masculino , Estrés Oxidativo , Ratas , Ratas Sprague-Dawley
5.
Abdom Radiol (NY) ; 46(4): 1752-1760, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33044652

RESUMEN

PURPOSE: To prospectively validate a method to accurately and rapidly differentiate normal from abnormal spinal bone mineral density (BMD) using colored abdominal CT images. METHODS: For this prospective observational study, 196 asymptomatic women ≥ 50 years of age presenting for screening mammograms underwent routine nonenhanced CT imaging of the abdomen. The CT images were processed with software designed to generate sagittal colored images with green vertebral trabecular bone indicating normal BMD and red indicating abnormal BMD (low BMD or osteoporosis). Four radiologists evaluated L1/L2 BMD on sagittal images using visual assessment of grayscale images, quantitative measurements of mean vertebral attenuation, and visual assessment of colored images. Mean BMD values at L1/L2 using quantitative CT with a phantom served as the reference standard. The average accuracy and time of interpretation were calculated. Inter-observer agreement was assessed using intraclass correlation coefficient (ICC). RESULTS: Mean attenuation at L1/L2 was highly correlated with mean BMD (r = 0.96/0.91, p < 0.001 for both). The average accuracy and mean time to assess BMD among four readers for differentiating normal from abnormal BMD was 66% and 6.0 s using visual assessment of grayscale images, 88% and 15.2 s using quantitative measurements of mean vertebral attenuation, and 92% and 2.1 s using visual assessment of colored images (p < 0.001 and p < 0.001, respectively). Inter-observer agreement was poor using visual assessment of grayscale images (ICC:0.31), good using quantitative measurements of mean vertebral attenuation (ICC:0.73), and excellent using visual assessment of colored images (ICC:0.90). CONCLUSION: Detection of abnormal BMD using colored abdominal CT images was highly accurate, rapid, and had excellent inter-observer agreement.


Asunto(s)
Densidad Ósea , Osteoporosis , Femenino , Humanos , Vértebras Lumbares/diagnóstico por imagen , Estudios Prospectivos , Tomografía Computarizada por Rayos X
6.
Brain ; 143(6): 1826-1842, 2020 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-32464655

RESUMEN

Repetitive mild traumatic brain injury in American football players has garnered increasing public attention following reports of chronic traumatic encephalopathy, a progressive tauopathy. While the mechanisms underlying repetitive mild traumatic brain injury-induced neurodegeneration are unknown and antemortem diagnostic tests are not available, neuropathology studies suggest a pathogenic role for microvascular injury, specifically blood-brain barrier dysfunction. Thus, our main objective was to demonstrate the effectiveness of a modified dynamic contrast-enhanced MRI approach we have developed to detect impairments in brain microvascular function. To this end, we scanned 42 adult male amateur American football players and a control group comprising 27 athletes practicing a non-contact sport and 26 non-athletes. MRI scans were also performed in 51 patients with brain pathologies involving the blood-brain barrier, namely malignant brain tumours, ischaemic stroke and haemorrhagic traumatic contusion. Based on data from prolonged scans, we generated maps that visualized the permeability value for each brain voxel. Our permeability maps revealed an increase in slow blood-to-brain transport in a subset of amateur American football players, but not in sex- and age-matched controls. The increase in permeability was region specific (white matter, midbrain peduncles, red nucleus, temporal cortex) and correlated with changes in white matter, which were confirmed by diffusion tensor imaging. Additionally, increased permeability persisted for months, as seen in players who were scanned both on- and off-season. Examination of patients with brain pathologies revealed that slow tracer accumulation characterizes areas surrounding the core of injury, which frequently shows fast blood-to-brain transport. Next, we verified our method in two rodent models: rats and mice subjected to repeated mild closed-head impact injury, and rats with vascular injury inflicted by photothrombosis. In both models, slow blood-to-brain transport was observed, which correlated with neuropathological changes. Lastly, computational simulations and direct imaging of the transport of Evans blue-albumin complex in brains of rats subjected to recurrent seizures or focal cerebrovascular injury suggest that increased cellular transport underlies the observed slow blood-to-brain transport. Taken together, our findings suggest dynamic contrast-enhanced-MRI can be used to diagnose specific microvascular pathology after traumatic brain injury and other brain pathologies.


Asunto(s)
Conmoción Encefálica/diagnóstico por imagen , Conmoción Encefálica/patología , Imagen por Resonancia Magnética/métodos , Adolescente , Adulto , Animales , Atletas , Barrera Hematoencefálica/metabolismo , Encéfalo/patología , Isquemia Encefálica/patología , Encefalopatía Traumática Crónica/patología , Imagen de Difusión Tensora , Fútbol Americano/lesiones , Humanos , Masculino , Microvasos/diagnóstico por imagen , Ratas , Ratas Sprague-Dawley , Accidente Cerebrovascular/patología , Tauopatías/patología , Estados Unidos , Sustancia Blanca/patología , Proteínas tau/metabolismo
7.
Anal Bioanal Chem ; 411(21): 5405-5413, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30382326

RESUMEN

Preterm birth (PTB) is defined as birth before the 37th week of pregnancy and results in 15 million early deliveries worldwide every year. Presently, there is no clinical test to determine PTB risk; however, a panel of nine biomarkers found in maternal blood serum has predictive power for a subsequent PTB. A significant step in creating a clinical diagnostic for PTB is designing an automated method to extract and purify these biomarkers from blood serum. Here, microfluidic devices with 45 µm × 50 µm cross-section channels were 3D printed with a built-in polymerization window to allow a glycidyl methacrylate monolith to be site-specifically polymerized within the channel. This monolith was then used as a solid support to attach antibodies for PTB biomarker extraction. Using these functionalized monoliths, it was possible to selectively extract a PTB biomarker, ferritin, from buffer and a human blood serum matrix. This is the first demonstration of monolith formation in a 3D printed microfluidic device for immunoaffinity extraction. Notably, this work is a crucial first step toward developing a 3D printed microfluidic clinical diagnostic for PTB risk.


Asunto(s)
Dispositivos Laboratorio en un Chip , Embarazo/sangre , Nacimiento Prematuro , Impresión Tridimensional/instrumentación , Biomarcadores/sangre , Femenino , Humanos , Recién Nacido , Polimerizacion
8.
Cureus ; 10(10): e3426, 2018 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-30542636

RESUMEN

Purpose The definition of radiotherapy target volume is a critical step in treatment planning for all tumor sites. Conventional magnetic resonance imaging (MRI) pulse sequences are used for the definition of the gross target volume (GTV) and the contouring of glioblastoma multiforme (GBM) and meningioma. We propose the use of multiparametric MRI combined with radiomic features to improve the texture-based differentiation of tumor from edema for GTV definition and to differentiate vasogenic from tumor cell infiltration edema. Methods Twenty-five patients with brain tumor and peritumoral edema (PTE) were assessed. Of the enrolled patients, 17 (63 ± 10 years old, six female and 11 male patients) were diagnosed with GBM and eight (64 ± 14 years old, five female and three male patients) with meningioma. A 3 Tesla (3T) MRI scanner was used to scan patients using a 3D multi-echo Gradient Echo (GRE) sequence. After the acquisition process, two experienced neuroradiologists independently used an in-house semiautomatic algorithm to conduct a segmentation of two regions of interest (ROI; edema and tumor) in all patients using functional MRI sequences, apparent diffusion coefficient (ADC), and dynamic contrast-enhanced MRI (DCE-MRI), as well as anatomical MRI sequences-T1-weighted, T2-weighted and fluid-attenuated inversion recovery (FLAIR). Radiomic (computer-extracted texture) features were extracted from all ROIs through different approaches, including first-, second-, and higher-order statistics, both with and without normalization, leading to the calculation of around 300 different texture parameters for each ROI. Based on the extracted parameters, a least absolute shrinkage and selection operator (LASSO) analysis was used to isolate the parameters that best differentiated edema from tumors while irrelevant parameters were discarded. Results and conclusions The parameters chosen by LASSO were used to perform statistical analyses which allowed identification of the variables with the best discriminant ability in all scenarios. Receiver operating characteristic results showcase both the best single discriminator and the discriminant capacity of the model using all variables selected by LASSO. Excellent results were obtained for patients with GBM with all MRI sequences, with and without normalization; a T1-weighted sequence postcontrast (T1W+C) with normalization offered the best tumor classification (area under the curve, AUC > 0.97). For patients with meningioma, a good model of tumor classification was obtained through the T1-weighted sequence (T1W) without normalization (AUC > 0.71). However, there was no agreement between the results of both radiologists for some MRI sequences analyzed for patients with GBM and meningioma. In conclusion, a small subset of radiomic features showed an excellent ability to distinguish edema from tumor tissue through its most discriminating features.

9.
Radiol Case Rep ; 13(3): 631-634, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30167024

RESUMEN

Liposarcoma of the larynx is a rare entity, typically well differentiated with a good prognosis. We present a patient who presented to ENT clinic with a 3-month history of hoarseness. Contrast-enhanced computed tomography of the neck demonstrated a 2.5-cm mass of the true vocal cord, which biopsy demonstrated to be dedifferentiated liposarcoma of the larynx. The patient went on to total laryngectomy with planned adjuvant radiation therapy. The presentation and imaging findings of laryngeal liposarcoma are nonspecific, but this neoplasm should be considered in the differential of masses in the head and neck.

10.
Case Rep Neurol Med ; 2018: 5070712, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30073102

RESUMEN

CONTEXT: We describe a case of unilateral posterior upper cervical spinal cord infarction and propose a pathophysiologic mechanism causing this lesion after vertebral artery endovascular intervention. FINDINGS: A 70-year-old male presented with subacute onset of left hemibody sensory changes and gait instability following a left vertebral angioplasty procedure. MRI cervical spine revealed upper posterior cervical spinal cord infarction (PSCI). After 3 months patient had substantial improvement of his symptoms. CONCLUSION: PSCI is rare but can present as a complication from vertebral artery angioplasty procedure. Early diagnosis of PSCI can be achieved with adequate understanding of its clinical signs and the blood supply of the spinal cord.

11.
Abdom Radiol (NY) ; 43(12): 3307-3316, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29700590

RESUMEN

PURPOSE: To evaluate precision of a software-based liver surface nodularity (LSN) score derived from CT images. METHODS: An anthropomorphic CT phantom was constructed with simulated liver containing smooth and nodular segments at the surface and simulated visceral and subcutaneous fat components. The phantom was scanned multiple times on a single CT scanner with adjustment of image acquisition and reconstruction parameters (N = 34) and on 22 different CT scanners from 4 manufacturers at 12 imaging centers. LSN scores were obtained using a software-based method. Repeatability and reproducibility were evaluated by intraclass correlation (ICC) and coefficient of variation. Using abdominal CT images from 68 patients with various stages of chronic liver disease, inter-observer agreement and test-retest repeatability among 12 readers assessing LSN by software- vs. visual-based scoring methods were evaluated by ICC. RESULTS: There was excellent repeatability of LSN scores (ICC:0.79-0.99) using the CT phantom and routine image acquisition and reconstruction parameters (kVp 100-140, mA 200-400, and auto-mA, section thickness 1.25-5.0 mm, field of view 35-50 cm, and smooth or standard kernels). There was excellent reproducibility (smooth ICC: 0.97; 95% CI 0.95, 0.99; CV: 7%; nodular ICC: 0.94; 95% CI 0.89, 0.97; CV: 8%) for LSN scores derived from CT images from 22 different scanners. Inter-observer agreement for the software-based LSN scoring method was excellent (ICC: 0.84; 95% CI 0.79, 0.88; CV: 28%) vs. good for the visual-based method (ICC: 0.61; 95% CI 0.51, 0.69; CV: 43%). Test-retest repeatability for the software-based LSN scoring method was excellent (ICC: 0.82; 95% CI 0.79, 0.84; CV: 12%). CONCLUSION: The software-based LSN score is a quantitative CT imaging biomarker with excellent repeatability, reproducibility, inter-observer agreement, and test-retest repeatability.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Hígado/diagnóstico por imagen , Fantasmas de Imagen , Tomografía Computarizada por Rayos X/métodos , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados
12.
BMC Med Educ ; 18(1): 32, 2018 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-29499682

RESUMEN

BACKGROUND: Although electronic cigarette (e-cigarette) use has rapidly increased, there is little data about what United States medical students know or are taught about them. This study examined medical students' experiences, knowledge, and attitudes regarding e-cigarettes, as well as their evaluation of their education on e-cigarettes. METHODS: A cross-sectional online survey of medical students currently enrolled at the University of Minnesota Medical School (n = 984) was conducted over a three-week period in August and September 2015. Primary outcomes included students' personal experiences with e-cigarettes, knowledge and attitudes about e-cigarettes, and students' assessment of their education on e-cigarettes. RESULTS: 66.9% medical students completed the survey. 58% (n = 382) of participants identified as female. 35.8% (n = 235) were "not sure" whether e-cigarettes were approved by the FDA for smoking cessation, while 4.1% (n = 27) falsely believed they were. While 82.9% (n = 543) agreed or strongly agreed that they felt confident in their ability to discuss traditional cigarette use with patients, only 12.4% (n = 81) agreed or strongly agreed that they felt confident in their ability to discuss e-cigarettes with patients. 94.8% (n = 619) of participants believed that they had not received adequate education about e-cigarettes in medical school. A higher proportion of males reported ever using an e-cigarette. CONCLUSIONS: The gaps in medical student knowledge and wide variances in attitudes about e-cigarettes at one medical school together with their report of inadequate education in an environment of increasing use of e-cigarette use in the U.S. speaks to a need for the development of medical school curriculum on e-cigarettes.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Conocimientos, Actitudes y Práctica en Salud , Estudiantes de Medicina/psicología , Adulto , Estudios Transversales , Femenino , Humanos , Masculino , Minnesota , Facultades de Medicina , Estudiantes de Medicina/estadística & datos numéricos , Encuestas y Cuestionarios
13.
Analyst ; 143(1): 224-231, 2017 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-29136068

RESUMEN

Biomarkers are often present in complex biological fluids like blood, requiring multiple, slow sample preparation steps that pose limitations in simplifying analysis. Here we report integrated immunoaffinity extraction and separation devices for analysis of preterm birth biomarkers in a human blood serum matrix. A reactive polymer monolith was used for immobilization of antibodies for selective extraction of target preterm birth biomarkers. Microfluidic immunoaffinity extraction protocols were optimized and then integrated with microchip electrophoresis for separation. Using these integrated devices, a ∼30 min analysis was carried out on low nanomolar concentrations of two preterm birth biomarkers spiked in a human serum matrix. This work is a promising step towards the development of an automated, integrated platform for determination of preterm birth risk.


Asunto(s)
Biomarcadores/sangre , Electroforesis por Microchip , Dispositivos Laboratorio en un Chip , Nacimiento Prematuro , Anticuerpos Inmovilizados , Femenino , Humanos , Recién Nacido , Embarazo
14.
Sci Rep ; 7: 45038, 2017 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-28332630

RESUMEN

The promyelocytic leukemia (PML) protein is an essential component of PML nuclear bodies (PML NBs) frequently lost in cancer. PML NBs coordinate chromosomal regions via modification of nuclear proteins that in turn may regulate genes in the vicinity of these bodies. However, few PML NB-associated genes have been identified. PML and PML NBs can also regulate mTOR and cell fate decisions in response to cellular stresses. We now demonstrate that PML depletion in U2OS cells or TERT-immortalized normal human diploid fibroblasts results in decreased expression of the mTOR inhibitor DDIT4 (REDD1). DNA and RNA immuno-FISH reveal that PML NBs are closely associated with actively transcribed DDIT4 loci, implicating these bodies in regulation of basal DDIT4 expression. Although PML silencing did reduce the sensitivity of U2OS cells to metabolic stress induced by metformin, PML loss did not inhibit the upregulation of DDIT4 in response to metformin, hypoxia-like (CoCl2) or genotoxic stress. Analysis of publicly available cancer data also revealed a significant correlation between PML and DDIT4 expression in several cancer types (e.g. lung, breast, prostate). Thus, these findings uncover a novel mechanism by which PML loss may contribute to mTOR activation and cancer progression via dysregulation of basal DDIT4 gene expression.


Asunto(s)
Regulación de la Expresión Génica , Proteína de la Leucemia Promielocítica/metabolismo , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Factores de Transcripción/genética , Línea Celular Tumoral , Cobalto/farmacología , Fibroblastos/metabolismo , Técnicas de Inactivación de Genes , Silenciador del Gen , Sitios Genéticos , Humanos , Hipoxia/genética , Hipoxia/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Unión Proteica , Biosíntesis de Proteínas , Radiación Ionizante , Factores de Transcripción/metabolismo , Transcripción Genética
15.
Radiol Case Rep ; 11(3): 238-41, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27594957

RESUMEN

Pneumocephalus and pneumorrhachis are related to transgression of the barriers to the central nervous system. We present a patient with a Pancoast tumor treated with palliative chemoradiation who developed symptomatic spinal and intracranial air caused by spontaneous bronchopleurodurosubarachnoid fistula secondary to direct tumor invasion into the thecal sac.

16.
J Acad Nutr Diet ; 116(1): 123-128, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26372337

RESUMEN

BACKGROUND: There are currently no national standards for school lunch period length and little is known about the association between the amount of time students have to eat and school food selection and consumption. OBJECTIVE: Our aim was to examine plate-waste measurements from students in the control arm of the Modifying Eating and Lifestyles at School study (2011 to 2012 school year) to determine the association between amount of time to eat and school meal selection and consumption. DESIGN: We used a prospective study design using up to six repeated measures among students during the school year. PARTICIPANTS/SETTING: One thousand and one students in grades 3 to 8 attending six participating elementary and middle schools in an urban, low-income school district where lunch period lengths varied from 20 to 30 minutes were included. MAIN OUTCOME MEASURES: School food selection and consumption were collected using plate-waste methodology. STATISTICAL ANALYSES PERFORMED: Logistic regression and mixed-model analysis of variance was used to examine food selection and consumption. RESULTS: Compared with meal-component selection when students had at least 25 minutes to eat, students were significantly less likely to select a fruit (44% vs 57%; P<0.0001) when they had <20 minutes to eat. There were no significant differences in entrée, milk, or vegetable selections. Among those who selected a meal component, students with <20 minutes to eat consumed 13% less of their entrée (P<0.0001), 10% less of their milk (P<0.0001), and 12% less of their vegetable (P<0.0001) compared with students who had at least 25 minutes to eat. CONCLUSIONS: During the school year, a substantial number of students had insufficient time to eat, which was associated with significantly decreased entrée, milk, and vegetable consumption compared with students who had more time to eat. School policies that encourage lunches with at least 25 minutes of seated time might reduce food waste and improve dietary intake.


Asunto(s)
Ingestión de Alimentos , Preferencias Alimentarias , Servicios de Alimentación , Almuerzo , Instituciones Académicas , Animales , Niño , Dieta , Etnicidad , Femenino , Frutas , Humanos , Masculino , Leche , Estudios Prospectivos , Estudiantes , Factores de Tiempo , Verduras
17.
JAMA Pediatr ; 169(5): 431-7, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25798990

RESUMEN

IMPORTANCE: Little is known about the long-term effect of a chef-enhanced menu on healthier food selection and consumption in school lunchrooms. In addition, it remains unclear if extended exposure to other strategies to promote healthier foods (eg, choice architecture) also improves food selection or consumption. OBJECTIVE: To evaluate the short- and long-term effects of chef-enhanced meals and extended exposure to choice architecture on healthier school food selection and consumption. DESIGN, SETTING, AND PARTICIPANTS: A school-based randomized clinical trial was conducted during the 2011-2012 school year among 14 elementary and middle schools in 2 urban, low-income school districts (intent-to-treat analysis). Included in the study were 2638 students in grades 3 through 8 attending participating schools (38.4% of eligible participants). INTERVENTIONS: Schools were first randomized to receive a professional chef to improve school meal palatability (chef schools) or to a delayed intervention (control group). To assess the effect of choice architecture (smart café), all schools after 3 months were then randomized to the smart café intervention or to the control group. MAIN OUTCOMES AND MEASURES: School food selection was recorded, and consumption was measured using plate waste methods. RESULTS: After 3 months, vegetable selection increased in chef vs control schools (odds ratio [OR], 1.75; 95% CI, 1.36-2.24), but there was no effect on the selection of other components or on meal consumption. After long-term or extended exposure to the chef or smart café intervention, fruit selection increased in the chef (OR, 3.08; 95% CI, 2.23-4.25), smart café (OR, 1.45; 95% CI, 1.13-1.87), and chef plus smart café (OR, 3.10; 95% CI, 2.26-4.25) schools compared with the control schools, and consumption increased in the chef schools (OR, 0.17; 95% CI, 0.03-0.30 cups/d). Vegetable selection increased in the chef (OR, 2.54; 95% CI, 1.83-3.54), smart café (OR, 1.91; 95% CI, 1.46-2.50), and chef plus smart café schools (OR, 7.38, 95% CI, 5.26-10.35) compared with the control schools, and consumption also increased in the chef (OR, 0.16; 95% CI, 0.09-0.22 cups/d) and chef plus smart café (OR, 0.13; 95% CI, 0.05-0.19 cups/d) schools; however, the smart café intervention alone had no effect on consumption. CONCLUSIONS AND RELEVANCE: Schools should consider both collaborating with chefs and using choice architecture to increase fruit and vegetable selection. Efforts to improve the taste of school foods through chef-enhanced meals should remain a priority because this was the only method that also increased consumption. This was observed only after students were repeatedly exposed to the new foods for 7 months. Therefore, schools should not abandon healthier options if they are initially met with resistance. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT02309840.


Asunto(s)
Preferencias Alimentarias , Servicios de Alimentación , Adolescente , Niño , Conducta de Elección , Humanos , Instituciones Académicas , Estudiantes , Verduras
18.
Am J Prev Med ; 46(4): 388-94, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24650841

RESUMEN

BACKGROUND: The U.S Department of Agriculture (USDA) recently made substantial changes to the school meal standards. The media and public outcry have suggested that this has led to substantially more food waste. PURPOSE: School meal selection, consumption, and waste were assessed before and after implementation of the new school meal standards. METHODS: Plate waste data were collected in four schools in an urban, low-income school district. Logistic regression and mixed-model ANOVA were used to estimate the differences in selection and consumption of school meals before (fall 2011) and after implementation (fall 2012) of the new standards among 1030 elementary and middle school children. Analyses were conducted in 2013. RESULTS: After the new standards were implemented, fruit selection increased by 23.0% and entrée and vegetable selection remained unchanged. Additionally, post-implementation entrée consumption increased by 15.6%, vegetable consumption increased by 16.2%, and fruit consumption remained the same. Milk selection and consumption decreased owing to an unrelated milk policy change. CONCLUSIONS: Although food waste levels were substantial both pre- and post-implementation, the new guidelines have positively affected school meal selection and consumption. Despite the increased vegetable portion size requirement, consumption increased and led to significantly more cups of vegetables consumed. Significantly more students selected a fruit, whereas the overall percentage of fruit consumed remained the same, resulting in more students consuming fruits. Contrary to media reports, these results suggest that the new school meal standards have improved students' overall diet quality. Legislation to weaken the standards is not warranted.


Asunto(s)
Dieta/normas , Preferencias Alimentarias , Servicios de Alimentación/normas , Instituciones Académicas/normas , Residuos/estadística & datos numéricos , Dieta/estadística & datos numéricos , Servicios de Alimentación/estadística & datos numéricos , Frutas , Humanos , Pobreza , Instituciones Académicas/estadística & datos numéricos , Estados Unidos , United States Department of Agriculture/normas , Población Urbana , Verduras
19.
J Acad Nutr Diet ; 112(6): 927-33, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22504283

RESUMEN

School cafeterias can play an important role in providing healthy meals. Although schools participating in the National School Lunch Program are required to meet minimum program standards, advocates recommend that innovations be sought to enhance menu dietary quality. This study evaluated the Chef Initiative, a 2-year pilot study in two Boston middle schools, designed to increase the availability and consumption of healthier school foods. Between 2007 and 2009, a professional chef trained cafeteria staff to prepare healthier school lunches (ie, more whole grains, fresh/frozen fruits and vegetables, and less sugar, salt, saturated fats, and trans fats). Meal nutrient compositions were monitored from 2007 to 2009, and a plate waste study conducted in the spring of 2009 compared food selection and consumption patterns among students at Chef Initiative schools, with students receiving standard school lunches at two matched control schools. Paired t tests and descriptive statistics were used to examine differences in menus and mixed-model analysis of variance was used to analyze differences in students' food selection and consumption between Chef Initiative and control schools. Overall, the Chef Initiative schools provided healthier lunches and the percent of foods consumed at Chef Initiative and control schools were similar (61.6% vs 57.3%; P=0.63). Of the areas targeted, there was greater whole-grain selection and vegetable consumption; 51% more students selected whole grains (P=0.02) and students consumed 0.36 more vegetable servings/day (P=0.01) at Chef Initiative schools. The potential of chefs collaborating with cafeteria staff to improve the availability, selection, and consumption of healthier meals is promising.


Asunto(s)
Culinaria/normas , Preferencias Alimentarias/psicología , Servicios de Alimentación/normas , Conductas Relacionadas con la Salud , Instituciones Académicas , Estudiantes/psicología , Adolescente , Fenómenos Fisiológicos Nutricionales de los Adolescentes , Análisis de Varianza , Boston , Estudios de Casos y Controles , Niño , Fenómenos Fisiológicos Nutricionales Infantiles , Conducta de Elección , Comportamiento del Consumidor , Femenino , Humanos , Masculino , Valor Nutritivo , Proyectos Piloto , Gusto
20.
AJR Am J Roentgenol ; 195(2): W164-71, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20651177

RESUMEN

OBJECTIVE: We summarize the rationale for and physiology of radiation therapy for the treatment of head and neck cancer and review the imaging findings of expected changes and complications after radiation to the neck. It is important to be able to recognize these features at all stages during management of patients with squamous cell carcinoma and other head and neck malignancies and to be able to distinguish these changes from residual or recurrent disease. CONCLUSION: Radiation therapy results in imaging findings of tissue edema followed by fibrosis, scarring, and atrophy. Complications from radiation therapy can occur months to years after treatment. Findings of a new mass, lymphadenopathy, or bone or cartilage destruction must be viewed as concerning for recurrent disease.


Asunto(s)
Diagnóstico por Imagen/métodos , Neoplasias de Cabeza y Cuello/complicaciones , Neoplasias de Cabeza y Cuello/radioterapia , Traumatismos por Radiación/diagnóstico , Traumatismos por Radiación/terapia , Radioterapia Conformacional/efectos adversos , Humanos , Traumatismos por Radiación/etiología
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