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1.
J Neurooncol ; 167(2): 349-359, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38427131

RESUMO

PURPOSE: Multidisciplinary tumor boards (MTBs) integrate clinical, molecular, and radiological information and facilitate coordination of neuro-oncology care. During the COVID-19 pandemic, our MTB transitioned to a virtual and multi-institutional format. We hypothesized that this expansion would allow expert review of challenging neuro-oncology cases and contribute to the care of patients with limited access to specialized centers. METHODS: We retrospectively reviewed records from virtual MTBs held between 04/2020-03/2021. Data collected included measures of potential clinical impact, including referrals to observational or therapeutic studies, referrals for specialized neuropathology analysis, and whether molecular findings led to a change in diagnosis and/or guided management suggestions. RESULTS: During 25 meetings, 32 presenters discussed 44 cases. Approximately half (n = 20; 48%) involved a rare central nervous system (CNS) tumor. In 21% (n = 9) the diagnosis was changed or refined based on molecular profiling obtained at the NIH and in 36% (n = 15) molecular findings guided management. Clinical trial suggestions were offered to 31% (n = 13), enrollment in the observational NCI Natural History Study to 21% (n = 9), neuropathology review and molecular testing at the NIH to 17% (n = 7), and all received management suggestions. CONCLUSION: Virtual multi-institutional MTBs enable remote expert review of CNS tumors. We propose them as a strategy to facilitate expert opinions from specialized centers, especially for rare CNS tumors, helping mitigate geographic barriers to patient care and serving as a pre-screening tool for studies. Advanced molecular testing is key to obtaining a precise diagnosis, discovering potentially actionable targets, and guiding management.


Assuntos
Neoplasias do Sistema Nervoso Central , Pandemias , Humanos , Estudos Retrospectivos , Neoplasias do Sistema Nervoso Central/diagnóstico , Neoplasias do Sistema Nervoso Central/terapia , Equipe de Assistência ao Paciente , Encaminhamento e Consulta
2.
Hum Genet ; 142(10): 1499-1517, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37668839

RESUMO

Enlargement of the endolymphatic sac, duct, and vestibular aqueduct (EVA) is the most common inner ear malformation identified in patients with sensorineural hearing loss. EVA is associated with pathogenic variants in SLC26A4. However, in European-Caucasian populations, about 50% of patients with EVA carry no pathogenic alleles of SLC26A4. We tested for the presence of variants in CHD7, a gene known to be associated with CHARGE syndrome, Kallmann syndrome, and hypogonadotropic hypogonadism, in a cohort of 34 families with EVA subjects without pathogenic alleles of SLC26A4. In two families, NM_017780.4: c.3553A > G [p.(Met1185Val)] and c.5390G > C [p.(Gly1797Ala)] were detected as monoallelic CHD7 variants in patients with EVA. At least one subject from each family had additional signs or potential signs of CHARGE syndrome but did not meet diagnostic criteria for CHARGE. In silico modeling of these two missense substitutions predicted detrimental effects upon CHD7 protein structure. Consistent with a role of CHD7 in this tissue, Chd7 transcript and protein were detected in all epithelial cells of the endolymphatic duct and sac of the developing mouse inner ear. These results suggest that some CHD7 variants can cause nonsyndromic hearing loss and EVA. CHD7 should be included in DNA sequence analyses to detect pathogenic variants in EVA patients. Chd7 expression and mutant phenotype data in mice suggest that CHD7 contributes to the formation or function of the endolymphatic sac and duct.


Assuntos
Surdez , Perda Auditiva Neurossensorial , Perda Auditiva , Aqueduto Vestibular , Animais , Camundongos , Alelos , DNA Helicases/genética , Perda Auditiva/genética , Perda Auditiva Neurossensorial/genética
3.
J Magn Reson Imaging ; 57(4): 1079-1092, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36056625

RESUMO

BACKGROUND: Dynamic diffusion magnetic resonance imaging (ddMRI) metrics can assess transient microstructural alterations in tissue diffusivity but requires additional scan time hindering its clinical application. PURPOSE: To determine whether a diffusion gradient table can simultaneously acquire data to estimate dynamic and diffusion tensor imaging (DTI) metrics. STUDY TYPE: Prospective. SUBJECTS: Seven healthy subjects, 39 epilepsy patients (15 female, 31 male, age ± 15). FIELD STRENGTH/SEQUENCE: Two-dimensional diffusion MRI (b = 1000 s/mm2 ) at a field strength of 3 T. Sessions in healthy subjects-standard ddMRI (30 directions), standard DTI (15 and 30 directions), and nested cubes scans (15 and 30 directions). Sessions in epilepsy patients-two 30 direction (standard ddMRI, 10 nested cubes) or two 15 direction scans (standard DTI, 5 nested cubes). ASSESSMENT: Fifteen direction DTI was repeated twice for within-session test-retest measurements in healthy subjects. Bland-Altman analysis computed bias and limits of agreement for DTI metrics using test-retest scans and standard 15 direction vs. 5 nested cubes scans. Intraclass correlation (ICC) analysis compared tensor metrics between 15 direction DTI scans (standard vs. 5 nested cubes) and the coefficients of variation (CoV) of trace and apparent diffusion coefficient (ADC) between 30 direction ddMRI scans (standard vs. 10 nested cubes). STATISTICAL TESTS: Bland-Altman and ICC analysis using a P-value of 0.05 for statistical significance. RESULTS: Correlations of mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) were strong and significant in gray (ICC > 0.95) and white matter (ICC > 0.95) between standard vs. nested cubes DTI acquisitions. Correlation of white matter fractional anisotropy was also strong (ICC > 0.95) and significant. ICCs of the CoV of dynamic ADC measured using repeated cubes and nested cubes acquisitions were modest (ICC >0.60), but significant in gray matter. CONCLUSION: A nested cubes diffusion gradient table produces tensor-based and dynamic diffusion measurements in a single acquisition. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 1.


Assuntos
Epilepsia , Substância Branca , Humanos , Masculino , Feminino , Adolescente , Imagem de Tensor de Difusão/métodos , Estudos Prospectivos , Imagem de Difusão por Ressonância Magnética , Substância Branca/patologia , Epilepsia/patologia , Anisotropia
4.
Pediatr Blood Cancer ; : e30358, 2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37347686

RESUMO

BACKGROUND: Chordomas are rare tumors arising from the skull base and spine, with approximately 20 pediatric chordoma cases in the Unitedn States per year. The natural history and optimal treatment of pediatric chordomas, especially poorly differentiated and dedifferentiated subtypes, is incompletely understood. Herein, we present findings from our first National Cancer Institute (NCI) chordoma clinic and a retrospective analysis of published cases of pediatric poorly differentiated chordomas (PDC) and dedifferentiated chordomas (DC). METHODS: Patients less than 40 years old with chordoma were enrolled on the NCI Natural History and Biospecimens Acquisitions Study for Children and Adults with Rare Solid Tumors protocol (NCT03739827). Chordoma experts reviewed patient records, evaluated patients, and provided treatment recommendations. Patient-reported outcomes, biospecimens, and volumetric tumor analyses were collected. A literature review for pediatric PDC and DC was conducted. RESULTS: Twelve patients (median age: 14 years) attended the clinic, including four patients with active disease and three patients with PDC responsive to systemic therapy. Consensus treatment, management, and recommendations were provided to patients. Literature review returned 45 pediatric cases of PDC or DC with variable treatments and outcomes. CONCLUSIONS: A multidisciplinary expert clinic was feasible and successful in improving understanding of pediatric chordoma. While multimodal approaches have all been employed, treatment for PDC has been inconsistent and a recommended standardized treatment approach has not been defined. Centralized efforts, inclusive of specialized chordoma-focused clinics, natural history studies, and prospective analyses will help in the standardization of care for this challenging disease.

5.
J Magn Reson Imaging ; 56(5): 1529-1535, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35852491

RESUMO

BACKGROUND: Susceptibility-weighted imaging (SWI) provides superior image contrast of cerebral microhemorrhages (CMBs). It is based on a three-dimensional (3D) gradient echo (GRE) sequence with a relatively long imaging time. PURPOSE: To evaluate whether an accelerated 3D segmented echo planar imaging SWI is comparable to GRE SWI in detecting CMBs in traumatic brain injury (TBI). STUDY TYPE: Prospective. SUBJECTS: Four healthy volunteers and 46 consecutive subjects (38.0 ± 14.4 years, 16 females; 12 mild, 13 moderate, and 7 severe TBI). FIELD STRENGTH/SEQUENCE: A 3 T scanner/3D gradient echo and 3D segmented echo planar imaging (segEPI). ASSESSMENT: Brain images were acquired using GRE and segEPI in a single session (imaging time = 9 minutes 47 seconds and 1 minute 30 seconds, respectively). The signal-to-noise ratio (SNR) calculated from healthy volunteer thalamus and centrum semiovale were compared. CMBs were counted by three raters blinded to diagnostic information. STATISTICAL TESTS: A t-test was used to assess SNR difference. Pearson correlation and Wilcoxon signed-rank test were performed using CMB counts. The intermethod agreement was evaluated using Bland-Altman method. Intermethod and interrater reliabilities of image-based diffuse axonal injury (DAI) diagnoses were evaluated using Cohen's kappa and percent agreement. P ≤ 0.05 was considered statistically significant. RESULTS: Thalamus SNRs were 16.9 ± 2.2 and 16.5 ± 3 for GRE and segEPI (P = 0.84), respectively. Centrum semiovale SNRs were 25.8 ± 4.6 and 21.1 ± 2.7 (P = 0.13). The correlation coefficient of CMBs was 0.93, and differences were not significant (P = 0.56-0.85). For DAI diagnoses, Cohen's kappa was 0.62-0.84 and percent agreement was 85%-94%. DATA CONCLUSION: CMB counts on segEPI and GRE were highly correlated, and DAI diagnosis was made equally effectively. segEPI SWI can potentially replace GRE SWI in detecting TBI CMBs, especially when time constraints are critical. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY: Stage 2.


Assuntos
Lesões Encefálicas Traumáticas , Lesão Axonal Difusa , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Imagem Ecoplanar/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Estudos Prospectivos
6.
Proc Natl Acad Sci U S A ; 114(37): E7766-E7775, 2017 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-28847925

RESUMO

The NLRP3 inflammasome is an intracellular innate immune sensor that is expressed in immune cells, including monocytes and macrophages. Activation of the NLRP3 inflammasome leads to IL-1ß secretion. Gain-of-function mutations of NLRP3 result in abnormal activation of the NLRP3 inflammasome, and cause the autosomal dominant systemic autoinflammatory disease spectrum, termed cryopyrin-associated periodic syndromes (CAPS). Here, we show that a missense mutation, p.Arg918Gln (c.2753G > A), of NLRP3 causes autosomal-dominant sensorineural hearing loss in two unrelated families. In family LMG446, hearing loss is accompanied by autoinflammatory signs and symptoms without serologic evidence of inflammation as part of an atypical CAPS phenotype and was reversed or improved by IL-1ß blockade therapy. In family LMG113, hearing loss segregates without any other target-organ manifestations of CAPS. This observation led us to explore the possibility that resident macrophage/monocyte-like cells in the cochlea can mediate local autoinflammation via activation of the NLRP3 inflammasome. The NLRP3 inflammasome can indeed be activated in resident macrophage/monocyte-like cells in the mouse cochlea, resulting in secretion of IL-1ß. This pathway could underlie treatable sensorineural hearing loss in DFNA34, CAPS, and possibly in a wide variety of hearing-loss disorders, such as sudden sensorineural hearing loss and Meniere's disease that are elicited by pathogens and processes that stimulate innate immune responses within the cochlea.


Assuntos
Perda Auditiva Neurossensorial/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Adulto , Animais , Sequência de Bases , Proteínas de Transporte/metabolismo , Cóclea/metabolismo , Síndromes Periódicas Associadas à Criopirina/genética , Síndromes Periódicas Associadas à Criopirina/metabolismo , Surdez/genética , Família , Feminino , Perda Auditiva , Perda Auditiva Neurossensorial/metabolismo , Humanos , Inflamassomos/metabolismo , Inflamação/metabolismo , Proteína Antagonista do Receptor de Interleucina 1/metabolismo , Proteína Antagonista do Receptor de Interleucina 1/farmacologia , Interleucina-1beta/antagonistas & inibidores , Interleucina-1beta/metabolismo , Masculino , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/fisiologia , Linhagem , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/metabolismo , Polimorfismo de Nucleotídeo Único/genética
7.
J Magn Reson Imaging ; 50(3): 951-960, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30681220

RESUMO

BACKGROUND: Arterial spin labeling with 3D acquisition requires determining a single postlabeling delay (PLD) value. PLD affects the signal-to-noise ratio (SNR) per unit time as well as quantitative cerebral blood flow (CBF) values due to its bearing on the presence of a vascular signal. PURPOSE: To search for an optimal PLD for pseudocontinuous arterial spin labeling (pCASL) using patient-specific carotid artery blood velocity measurements. STUDY TYPE: Prospective. SUBJECTS: A control group of 11 volunteers with no known pathology. Corroboration was through a separate group of six volunteers and a noncontrol group of five sickle cell disease (SCD) patients. FIELD STRENGTH/SEQUENCE: Pseudocontinuous arterial spin labeling with 3D nonsegmented echo planar imaging acquisition at 3T. ASSESSMENT: A perfusion-based measure was determined over a range of PLDs for each of 11 volunteers. A third-order polynomial was used to find the optimal PLD where the defined measure was maximum. This was plotted against the corresponding carotid artery velocity to determine a relationship between the perfusion measure and velocity. Corroboration was done using a group of six volunteers and a noncontrol group of five patients with SCD. PLD was determined from the carotid artery velocity and derived relationship and compared with optimal PLD obtained from measured perfusion over a range of PLD values. Error between the perfusion measure at predicted and measured optimal PLD was determined. STATISTICAL TESTS: Chi-squared goodness of fit; Pearson correlation; Bland-Altman. RESULTS: Carotid artery velocity was 63.8 ± 6.6 cm/s (53.1 ≤ v ≤ 72.3 cm/s) while optimal PLD was 1374 ± 226.5 msec (1102 ≤ PLD ≤ 1787 msec) across the 11 volunteers. PLD as a function of carotid velocity was determined to be PLD = -31.94. v + 3410 msec (Pearson correlation -0.93). In six volunteers, mean error between the perfusion measure at predicted and measured optimal PLD was 1.35%. Pearson correlation between the perfusion measure at the predicted PLD and the measure obtained experimentally was r = 0.96 (P < 0.001). Bland-Altman revealed a slight bias of 1.3%. For the test case of five SCD patients, the mean error was 1.3%. DATA CONCLUSION: Carotid artery velocity was used to determine optimal PLD for pCASL with 3D acquisition. The derived relationship was used to predict optimal PLD and the associated perfusion measure, which was found to be accurate when compared with its measured counterpart. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2019;50:951-960.


Assuntos
Anemia Falciforme/fisiopatologia , Artérias Carótidas/diagnóstico por imagem , Artérias Carótidas/fisiopatologia , Circulação Cerebrovascular/fisiologia , Imageamento por Ressonância Magnética/métodos , Adulto , Imagem Ecoplanar/métodos , Feminino , Humanos , Imageamento Tridimensional/métodos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Razão Sinal-Ruído , Marcadores de Spin , Adulto Jovem
8.
J Neurooncol ; 139(1): 145-152, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29767308

RESUMO

INTRODUCTION: Pseudoprogression (PsP) is a diagnostic dilemma in glioblastoma (GBM) after chemoradiotherapy (CRT). Magnetic resonance imaging (MRI) features may fail to distinguish PsP from early true progression (eTP), however clinical findings may aid in their distinction. METHODS: Sixty-seven patients received CRT for GBM between 2003 and 2016, and had pre- and post-treatment imaging suitable for retrospective evaluation using RANO criteria. Patients with signs of progression within the first 12-weeks post-radiation (P-12) were selected. Lesions that improved or stabilized were defined as PsP, and lesions that progressed were defined as eTP. RESULTS: The median follow up for all patients was 17.6 months. Signs of progression developed in 35/67 (52.2%) patients within P-12. Of these, 20/35 (57.1%) were subsequently defined as eTP and 15/35 (42.9%) as PsP. MRI demonstrated increased contrast enhancement in 84.2% of eTP and 100% of PsP, and elevated CBV in 73.7% for eTP and 93.3% for PsP. A decrease in FLAIR was not seen in eTP patients, but was seen in 26.7% PsP patients. Patients with eTP were significantly more likely to require increased steroid doses or suffer clinical decline than PsP patients (OR 4.89, 95% CI 1.003-19.27; p = 0.046). KPS declined in 25% with eTP and none of the PsP patients. CONCLUSIONS: MRI imaging did not differentiate eTP from PsP, however, KPS decline or need for increased steroids was significantly more common in eTP versus PsP. Investigation and standardization of clinical assessments in response criteria may help address the diagnostic dilemma of pseudoprogression after frontline treatment for GBM.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/terapia , Glioblastoma/diagnóstico por imagem , Glioblastoma/terapia , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Quimiorradioterapia , Meios de Contraste , Progressão da Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Esteroides/uso terapêutico , Resultado do Tratamento
9.
AJR Am J Roentgenol ; 210(5): 1111-1117, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29547058

RESUMO

OBJECTIVE: Radiation exposure of the lens during neck CT may increase a patient's risk of developing cataracts. Radiologists at the National Institutes of Health worked with technicians to modify the neck CT scanning procedure to include a reduction in the scanning range, a reduction in the tube potential (kilovoltage), and a change in neck positioning using a head tilt. We objectively quantified the organ dose changes after this procedure modification using a computer simulation. MATERIALS AND METHODS: We retrospectively analyzed CT images of 40 patients (20 men and 20 women) scanned before and after the procedure change. Radiation dose to the lens delivered before and after the procedure change was calculated using an in-house CT dose calculator combined with computational human phantoms deformed to match head tilt angles. We also calculated the doses to other radiosensitive organs including the brain, pituitary gland, eye globes, and salivary glands before and after the procedure change. RESULTS: Our dose calculations showed that modifying the neck position, shortening the scanning range, and reducing the tube potential reduced the dose to the lens by 89% (p < 0.0001). The median brain, pituitary gland, globes, and salivary gland doses also decreased by 59%, 52%, 66%, and 29%, respectively. We found that overranging significantly affects the lens dose. CONCLUSION: Combining head tilt and scanning range reduction is an easy and effective method that significantly reduces radiation dose to the lens and other radiosensitive head and neck organs.


Assuntos
Catarata/prevenção & controle , Cristalino/efeitos da radiação , Pescoço/diagnóstico por imagem , Posicionamento do Paciente , Lesões por Radiação/prevenção & controle , Proteção Radiológica/métodos , Tomografia Computadorizada por Raios X , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doses de Radiação , Estudos Retrospectivos
10.
J Biomech Eng ; 140(10)2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30029236

RESUMO

Understanding of in vivo brain biomechanical behavior is critical in the study of traumatic brain injury (TBI) mechanisms and prevention. Using tagged magnetic resonance imaging, we measured spatiotemporal brain deformations in 34 healthy human volunteers under mild angular accelerations of the head. Two-dimensional (2D) Lagrangian strains were examined throughout the brain in each subject. Strain metrics peaked shortly after contact with a padded stop, corresponding to the inertial response of the brain after head deceleration. Maximum shear strain of at least 3% was experienced at peak deformation by an area fraction (median±standard error) of 23.5±1.8% of cortical gray matter, 15.9±1.4% of white matter, and 4.0±1.5% of deep gray matter. Cortical gray matter strains were greater in the temporal cortex on the side of the initial contact with the padded stop and also in the contralateral temporal, frontal, and parietal cortex. These tissue-level deformations from a population of healthy volunteers provide the first in vivo measurements of full-volume brain deformation in response to known kinematics. Although strains differed in different tissue type and cortical lobes, no significant differences between male and female head accelerations or strain metrics were found. These cumulative results highlight important kinematic features of the brain's mechanical response and can be used to facilitate the evaluation of computational simulations of TBI.


Assuntos
Aceleração , Encéfalo/diagnóstico por imagem , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Adulto , Feminino , Voluntários Saudáveis , Humanos , Masculino , Rotação , Estresse Mecânico
11.
Neuroimage ; 146: 132-147, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-27864083

RESUMO

Automatic skull-stripping or brain extraction of magnetic resonance (MR) images is often a fundamental step in many neuroimage processing pipelines. The accuracy of subsequent image processing relies on the accuracy of the skull-stripping. Although many automated stripping methods have been proposed in the past, it is still an active area of research particularly in the context of brain pathology. Most stripping methods are validated on T1-w MR images of normal brains, especially because high resolution T1-w sequences are widely acquired and ground truth manual brain mask segmentations are publicly available for normal brains. However, different MR acquisition protocols can provide complementary information about the brain tissues, which can be exploited for better distinction between brain, cerebrospinal fluid, and unwanted tissues such as skull, dura, marrow, or fat. This is especially true in the presence of pathology, where hemorrhages or other types of lesions can have similar intensities as skull in a T1-w image. In this paper, we propose a sparse patch based Multi-cONtrast brain STRipping method (MONSTR),2 where non-local patch information from one or more atlases, which contain multiple MR sequences and reference delineations of brain masks, are combined to generate a target brain mask. We compared MONSTR with four state-of-the-art, publicly available methods: BEaST, SPECTRE, ROBEX, and OptiBET. We evaluated the performance of these methods on 6 datasets consisting of both healthy subjects and patients with various pathologies. Three datasets (ADNI, MRBrainS, NAMIC) are publicly available, consisting of 44 healthy volunteers and 10 patients with schizophrenia. Other three in-house datasets, comprising 87 subjects in total, consisted of patients with mild to severe traumatic brain injury, brain tumors, and various movement disorders. A combination of T1-w, T2-w were used to skull-strip these datasets. We show significant improvement in stripping over the competing methods on both healthy and pathological brains. We also show that our multi-contrast framework is robust and maintains accurate performance across different types of acquisitions and scanners, even when using normal brains as atlases to strip pathological brains, demonstrating that our algorithm is applicable even when reference segmentations of pathological brains are not available to be used as atlases.


Assuntos
Mapeamento Encefálico , Encéfalo/anatomia & histologia , Encéfalo/patologia , Imageamento por Ressonância Magnética , Crânio/anatomia & histologia , Crânio/patologia , Algoritmos , Atlas como Assunto , Encéfalo/diagnóstico por imagem , Meios de Contraste , Bases de Dados Factuais , Humanos , Aumento da Imagem , Processamento de Imagem Assistida por Computador , Reconhecimento Automatizado de Padrão , Crânio/diagnóstico por imagem
12.
Hum Brain Mapp ; 37(9): 3236-49, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27144466

RESUMO

Previous work using transcranial magnetic stimulation (TMS) demonstrated that the right presupplementary motor area (preSMA), a node in the fronto-basal-ganglia network, is critical for response inhibition. However, TMS influences interconnected regions, raising the possibility of a link between the preSMA activity and the functional connectivity within the network. To understand this relationship, we applied single-pulse TMS to the right preSMA during functional magnetic resonance imaging when the subjects were at rest to examine changes in neural activity and functional connectivity within the network in relation to the efficiency of response inhibition evaluated with a stop-signal task. The results showed that preSMA-TMS increased activation in the right inferior-frontal cortex (rIFC) and basal ganglia and modulated their task-free functional connectivity. Both the TMS-induced changes in the basal-ganglia activation and the functional connectivity between rIFC and left striatum, and of the overall network correlated with the efficiency of response inhibition and with the white-matter microstructure along the preSMA-rIFC pathway. These results suggest that the task-free functional and structural connectivity between the rIFCop and basal ganglia are critical to the efficiency of response inhibition. Hum Brain Mapp 37:3236-3249, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Córtex Cerebral/fisiologia , Inibição Psicológica , Vias Neurais/fisiologia , Mapeamento Encefálico , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Estimulação Magnética Transcraniana , Adulto Jovem
13.
J Neurooncol ; 127(1): 127-35, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26643807

RESUMO

We evaluated the efficacy of combination enzastaurin (LY317615) and bevacizumab for recurrent malignant gliomas and explored serologic correlates. We enrolled 81 patients with glioblastomas (GBM, n = 40) and anaplastic gliomas (AG, n = 41). Patients received enzastaurin as a loading dose of 1125 mg, followed by 500 or 875 mg daily for patients on non-enzyme-inducing or enzyme-inducing antiepileptics, respectively. Patients received bevacizumab 10 mg/kg intravenously biweekly. Clinical evaluations were repeated every 4 weeks. Magnetic resonance imaging was obtained at baseline and every 8 weeks from treatment onset. Phosphorylated glycogen synthase kinase (GSK)-3 levels from peripheral blood mononuclear cells (PBMCs) were checked with each MRI. Median overall survival was 7.5 and 12.4 months for glioblastomas and anaplastic glioma cohorts, with median progression-free survivals of 2.0 and 4.4 months, respectively. Of GBM patients, 3/40 (7.5 %) were not evaluable, while 8/37 (22 %) had partial or complete response and 20/37 (54 %) had stable disease for 2+ months. Of the 39 evaluable AG patients, 18 (46 %) had an objective response, and 16 (41 %) had stable disease for 2+ months. The most common grade 3+ toxicities were lymphopenia (15 %), hypophosphatemia (8.8 %) and thrombotic events (7.5 %). Two (2.5 %) GBM patients died suddenly; another death (1.3 %) occurred from intractable seizures. Phosphorylated GSK-3 levels from PBMCs did not correlate with treatment response. A minimally important improvement in health-related quality of life was self-reported in 7-9/24 (29.2-37.5 %). Early response based on Levin criteria was significantly associated with significantly longer progression free survival for glioblastomas. Enzastaurin (LY317615) in combination with bevacizumab for recurrent malignant gliomas is well-tolerated, with response and progression-free survival similar to bevacizumab monotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Glioma/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Adulto , Idoso , Bevacizumab/administração & dosagem , Neoplasias Encefálicas/patologia , Feminino , Seguimentos , Glioma/patologia , Quinase 3 da Glicogênio Sintase/metabolismo , Humanos , Indóis/administração & dosagem , Leucócitos Mononucleares/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Prognóstico , Qualidade de Vida , Taxa de Sobrevida
14.
J Sleep Res ; 25(1): 16-22, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26439359

RESUMO

In rodent studies, paired box 6 (PAX6) appears to play an important role in the development of the pineal, the primary source of the circadian regulating hormone, melatonin. Pineal hypoplasia has been previously reported in patients with PAX6 haploinsufficiency (+/−); however, pineal measurement, melatonin concentrations and sleep quality have not been reported. This cross-sectional descriptive study examined pineal volume, melatonin secretion and sleep disturbance in 37 patients with PAX6+/− (age 15.3 ± 9.9 years) and 17 healthy controls (16.0 ± 7.2 years), within an inpatient setting at the Clinical Research Center of the National Institutes of Health, Bethesda, Maryland, USA. Pineal volume was evaluated by magnetic resonance imaging. Diurnal serum cortisol, serum melatonin and urine 6-sulphatoxymelatonin concentrations were measured by enzyme-linked immunosorbent assay. The Child Sleep Habits Questionnaire was administered for patients <13 years old. Pineal volume was fivefold lower in PAX6+/− versus controls (mean ± SD: 25 ± 15 versus 129 ± 50 µL, P < 0.001). Midnight serum cortisol was similar in PAX6+/− versus controls (P = 0.14). Midnight serum melatonin was > twofold lower in PAX6+/− versus controls [median (25th-75 th): 28 (22-42) versus 71 (46-88) pg mL-(1), P < 0.001]. First morning void urinary 6-sulphatoxymelatonin was fourfold lower in PAX6+/− versus controls [11 (6-26) versus 45 (34-61) ng mg(-1) Cr, P = 0.001]. Child Sleep Habits Questionnaire score was higher in PAX6+/− versus controls (48 ± 6 versus 41 ± 5, P = 0.03). The current findings suggest that PAX6+/− is associated with smaller pineal size, lower melatonin secretion and greater parental report of sleep disturbances in children. Further studies are needed to explore the potential use of melatonin replacement for improving sleep quality in patients with PAX6+/−.


Assuntos
Proteínas do Olho/genética , Haploinsuficiência/genética , Proteínas de Homeodomínio/genética , Melatonina/metabolismo , Fatores de Transcrição Box Pareados/deficiência , Fatores de Transcrição Box Pareados/genética , Glândula Pineal/patologia , Proteínas Repressoras/deficiência , Proteínas Repressoras/genética , Transtornos do Sono-Vigília/genética , Transtornos do Sono-Vigília/fisiopatologia , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Pré-Escolar , Estudos Transversais , Feminino , Hábitos , Humanos , Hidrocortisona/sangue , Imageamento por Ressonância Magnética , Masculino , Maryland , Melatonina/análogos & derivados , Melatonina/sangue , Melatonina/urina , Fator de Transcrição PAX6 , Pais , Sono/fisiologia , Inquéritos e Questionários , Fatores de Tempo , Adulto Jovem
15.
Ann Rheum Dis ; 74(9): 1714-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24906637

RESUMO

OBJECTIVE: To study efficacy and safety of escalating doses of canakinumab, a fully human anti-IL-1ß monoclonal antibody in the severe cryopyrin-associated periodic syndrome, neonatal-onset multisystem inflammatory disease (NOMID). METHODS: 6 patients were enrolled in this 24-month, open-label phase I/II study. All underwent anakinra withdrawal. The initial subcutaneous canakinumab dose was 150 mg (or 2 mg/kg in patients ≤40 kg) or 300 mg (or 4 mg/kg) with escalation up to 600 mg (or 8 mg/kg) every 4 weeks. Full remission was remission of patient-reported clinical components and measures of systemic inflammation and CNS inflammation. Hearing, vision and safety were assessed. Primary endpoint was full remission at month 6. RESULTS: All patients flared after anakinra withdrawal, and symptoms and serum inflammatory markers improved with canakinumab. All patients required dose escalation to the maximum dose. At month 6, none had full remission, although 4/6 achieved inflammatory remission, based on disease activity diary scores and normal C-reactive proteins. None had CNS remission; 5/6 due to persistent CNS leucocytosis. At the last study visit, 5/6 patients achieved inflammatory remission and 4/6 had continued CNS leucocytosis. Visual acuity and field were stable in all patients, progressive hearing loss occurred in 1/10 ears. Adverse events (AEs) were rare. One serious AE (abscess due to a methicillin-resistant Staphylococcus aureus infection) occurred. CONCLUSIONS: Canakinumab at the studied doses improves symptoms and serum inflammatory features of NOMID, although low-grade CNS leukocytosis in four patients and headaches in one additional patient persisted. Whether further dose intensifications are beneficial in these cases remains to be assessed. CLINICALTRIALSGOV IDENTIFIER: NCT00770601.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Síndromes Periódicas Associadas à Criopirina/tratamento farmacológico , Interleucina-1beta/antagonistas & inibidores , Adolescente , Adulto , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Proteína C-Reativa/metabolismo , Líquido Cefalorraquidiano/citologia , Criança , Síndromes Periódicas Associadas à Criopirina/complicações , Síndromes Periódicas Associadas à Criopirina/metabolismo , Feminino , Cefaleia/tratamento farmacológico , Cefaleia/etiologia , Humanos , Contagem de Leucócitos , Masculino , Indução de Remissão , Resultado do Tratamento , Adulto Jovem
16.
J Magn Reson Imaging ; 41(5): 1440-6, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-24979311

RESUMO

BACKGROUND: The purpose of this study is to design and evaluate a new reduced scan time three-dimensional (3D) FLuid Attenuated Inversion Recovery (FLAIR) sequence. METHODS: The 3D FLAIR sequence was modified so that the repetition time was modulated in a predetermined smooth manner (3D mFLAIR). Inversion times were adjusted accordingly to maintain cerebrospinal fluid (CSF) suppression. Simulations were performed to determine SNR for gray matter (GM), white matter (WM), and CSF. Fourteen volunteers were imaged using the modified and product sequence. SNR measurements were performed in GM, WM, and CSF. Mean value and the 95% confidence interval ([CI]) were assessed. Scan time for the 3D FLAIR and 3D mFLAIR sequences was measured. RESULTS: There was no statistically significant difference in the SNR measured in GM (P value = 0.5; mean SNR = 42.8 [CI]: 38.2-45.5 versus 42.2 [CI]: 38.3-46.1 for 3D FLAIR and 3D mFLAIR, respectively) and WM (P value = 0.25; mean SNR = 32.1 [CI]: 30.3-33.8 versus 32.9 [CI]: 31.1-34.7). Scan time reduction greater than 30% was achieved for the given parameter set with the 3D mFLAIR sequence. CONCLUSION: Scan time for 3D FLAIR can be effectively reduced by modulating repetition and inversion time in a predetermined manner while maintaining the SNR and CNR of a constant TR sequence.


Assuntos
Algoritmos , Encéfalo/anatomia & histologia , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Processamento de Sinais Assistido por Computador , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fatores de Tempo , Adulto Jovem
17.
J Magn Reson Imaging ; 41(6): 1695-700, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25143262

RESUMO

BACKGROUND: To report that artifactual microhemorrhages are introduced by the two-dimensional (2D) homodyne filtering method of generating susceptibility weighted images (SWI) when open-ended fringelines (OEF) are present in phase data. METHODS: SWI data from 28 traumatic brain injury (TBI) patients was obtained on a 3 tesla clinical Siemens scanner using both the product 3D gradient echo sequence (GRE) with generalized autocalibrating partially parallel acquisition acceleration and an in-house developed segmented echo planar imaging (sEPI) sequence without GRAPPA acceleration. SWI processing included (i) 2D homodyne method implemented on the scanner console and (ii) a 3D Fourier-based phase unwrapping followed by 3D high pass filtering. Original and enhanced magnitude and phase images were carefully reviewed for sites of type III OEFs and microhemorrhages by a neuroradiologist on a PACS workstation. RESULTS: Nineteen of 28 (68%) phase datasets acquired using GRAPPA-accelerated GRE acquisition demonstrated type III OEFs. In SWI images, artifactual microhemorrhages were found on 17 of 19 (89%) cases generated using 2D homodyne processing. Application of a 3D Fourier-based unwrapping method prior HP filtering minimized the appearance of the phase singularities in the enhanced phase, and did not generate microhemorrhage-like artifacts in magnitude images. CONCLUSION: The 2D homodyne filtering method may introduce artifacts mimicking intracranial microhemorrhages in SWI images when type III OEFs are present in phase images. Such artifacts could lead to overestimation of pathology, e.g., TBI. This work demonstrates that 3D phase unwrapping methods minimize this artifact. However, methods to properly combine phase across coils are needed to eliminate this artifact.


Assuntos
Artefatos , Lesões Encefálicas/complicações , Imagem Ecoplanar/métodos , Processamento de Imagem Assistida por Computador/métodos , Hemorragia Cerebral/diagnóstico , Humanos , Imageamento Tridimensional
18.
J Magn Reson Imaging ; 40(6): 1463-73, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24923594

RESUMO

PURPOSE: To evaluate different susceptibility-weighted imaging (SWI) phase processing methods and parameter selection, thereby improving understanding of potential artifacts, as well as facilitating choice of methodology in clinical settings. MATERIALS AND METHODS: Two major phase processing methods, homodyne-filtering and phase unwrapping-high pass (HP) filtering, were investigated with various phase unwrapping approaches, filter sizes, and filter types. Magnitude and phase images were acquired from a healthy subject and brain injury patients on a 3T clinical Siemens MRI system. The results were evaluated based on image contrast-to-noise ratio and presence of processing artifacts. RESULTS: When using a relatively small filter size (32 pixels for the matrix size 512 × 512 pixels), all homodyne-filtering methods were subject to phase errors leading to 2% to 3% masked brain area in lower and middle axial slices. All phase unwrapping-filtering/smoothing approaches demonstrated fewer phase errors and artifacts compared to the homodyne-filtering approaches. For performing phase unwrapping, Fourier-based methods, although less accurate, were 2-4 orders of magnitude faster than the PRELUDE, Goldstein, and Quality-guide methods. CONCLUSION: Although homodyne-filtering approaches are faster and more straightforward, phase unwrapping followed by HP filtering approaches perform more accurately in a wider variety of acquisition scenarios.


Assuntos
Algoritmos , Artefatos , Encéfalo/anatomia & histologia , Imagem de Difusão por Ressonância Magnética/métodos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
20.
Hum Mutat ; 34(9): 1250-9, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23661601

RESUMO

Melanoma is the most deadly form of skin cancer and DiGeorge syndrome (DGS) is the most frequent interstitial deletion syndrome. We characterized a novel balanced t(9;22)(p21;q11.2) translocation in a patient with melanoma, DNA repair deficiency, and features of DGS including deafness and malformed inner ears. Using chromosome sorting, we located the 9p21 breakpoint in CDKN2A intron 1. This resulted in underexpression of the tumor suppressor p14 alternate reading frame (p14ARF); the reduced DNA repair was corrected by transfection with p14ARF. Ultraviolet radiation-type p14ARF mutations in his melanoma implicated p14ARF in its pathogenesis. The 22q11.2 breakpoint was located in a palindromic AT-rich repeat (PATRR22). We identified a new gene, FAM230A, that contains PATRR22 within an intron. The 22q11.2 breakpoint was located 800 kb centromeric to TBX1, which is required for inner ear development. TBX1 expression was greatly reduced. The translocation resulted in a chimeric transcript encoding portions of p14ARF and FAM230A. Inhibition of chimeric p14ARF-FAM230A expression increased p14ARF and TBX1 expression and improved DNA repair. Expression of the chimera in normal cells produced dominant negative inhibition of p14ARF. Similar chimeric mRNAs may mediate haploinsufficiency in DGS or dominant negative inhibition of other genes such as those involved in melanoma.


Assuntos
Distúrbios no Reparo do DNA/genética , Surdez/genética , Fusão Gênica , Melanoma/genética , Proteínas com Domínio T/genética , Translocação Genética , Proteína Supressora de Tumor p14ARF/genética , Sequência de Bases , Proteínas de Transporte , Cromossomos Humanos Par 22 , Cromossomos Humanos Par 9 , Distúrbios no Reparo do DNA/metabolismo , Surdez/metabolismo , Genes p16 , Humanos , Masculino , Melanoma/metabolismo , Dados de Sequência Molecular , RNA Longo não Codificante , Análise de Sequência de DNA , Proteínas com Domínio T/metabolismo , Proteína Supressora de Tumor p14ARF/metabolismo , Adulto Jovem
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