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1.
World J Surg ; 47(11): 2825-2833, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37541981

RESUMO

BACKGROUND: The prevalence and impact of sarcopenia and sarcopenic obesity noted on body composition analysis in severe acute pancreatitis (SAP) is unknown. This study investigates the prevalence of sarcopenia at different timepoints and its effect on post-pancreatitis complications and mortality. METHODS: A prospective database of SAP admissions with organ failure at a single institution from 2015 to 2019 were analysed. Sarcopenia was determined by IMAGE J software on CT. Database was further queried for post-pancreatitis complications and mortality. RESULTS: 141 patients with a median age of 59 (range 18-88) and M:F ratio 1.52:1 of were analysed. Sarcopenia was present in 111/141 (79%) patients at admission, 78/79 (99%) at 3 months and 26/36 (72%) at 12 months. 67/111 patients with sarcopenia on admission had sarcopenic obesity. The mortality at 30 days, 3 months and 12 months was 16/141 (11%), 30/141 (21%) and 42/141 (30%) respectively. Mortality was significantly higher in sarcopenic patients at admission (35.14%) compared to the non-sarcopenic group (10%), P = 0.008). Mortality in the sarcopenic obesity group was significantly higher (45%) compared to the sarcopenic non-obese group (20%), P = 0.009) at admission. Multivariate logistic regression identified sarcopenic obesity (OR: 2.880), age (OR: 1.048) and number of organ failures (OR: 3.225) as significant predictors of mortality. CONCLUSIONS: Sarcopenia and Sarcopenic obesity are highly prevalent in SAP patients on admission and during follow up. Furthermore, sarcopenic obesity was shown to be a significant predictor of mortality at admission, suggesting that body composition analysis could be a potential predictive marker of mortality in SAP patients.


Assuntos
Pancreatite , Sarcopenia , Humanos , Sarcopenia/complicações , Sarcopenia/epidemiologia , Doença Aguda , Pancreatite/complicações , Obesidade/epidemiologia , Composição Corporal
2.
MethodsX ; 10: 102141, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37091957

RESUMO

Stochastic field reconstruction is a crucial technique to improve the accuracy of modern rock simulation. It allows explicit modelling of field conditions, often employed in uncertainty quantification analysis and upsampling and upscaling procedures. This paper presents a case-study of a framework for the stochastic reconstruction of rock's strain field using experimental data. The proposed framework is applied to a limestone outcrop in which the strain field is measured using Digital Image Correlation (DIC). Assuming that the strain fields of these rocks are well-represented by Gaussian random fields, we capitalize on the algorithms used for training Gaussian processes to estimate the correlation family and the parameters that best represent these fields. Although the spherical and exponential kernels often correspond to the best fit, our results depict that each field shall be analyzed separately and no general rule can be defined. We show that the method is versatile and can be employed in any measurable field reasonably represented by a Gaussian random field. Therefore, the present work aims to highlight the following topics:•A study-case of stochastic strain field reconstruction aims to contribute to uncertainty quantification of rock experimental procedures.•A stochastic minimization algorithm is presented to solve the maximum likelihood estimation to define the most suitable hyper-parameter: correlation length.•The calculated hyper-parameters of a set correlation functions are presented to best reproduce the strain fields of a rock sample.

3.
Diagnostics (Basel) ; 12(4)2022 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-35454035

RESUMO

Blast-related mild traumatic brain injury (bmTBI) often leads to long-term sequalae, but diagnostic approaches are lacking due to insufficient knowledge about the predominant pathophysiology. This study aimed to build a diagnostic model for future verification by applying machine-learning based support vector machine (SVM) modeling to diffusion tensor imaging (DTI) datasets to elucidate white-matter features that distinguish bmTBI from healthy controls (HC). Twenty subacute/chronic bmTBI and 19 HC combat-deployed personnel underwent DTI. Clinically relevant features for modeling were selected using tract-based analyses that identified group differences throughout white-matter tracts in five DTI metrics to elucidate the pathogenesis of injury. These features were then analyzed using SVM modeling with cross validation. Tract-based analyses revealed abnormally decreased radial diffusivity (RD), increased fractional anisotropy (FA) and axial/radial diffusivity ratio (AD/RD) in the bmTBI group, mostly in anterior tracts (29 features). SVM models showed that FA of the anterior/superior corona radiata and AD/RD of the corpus callosum and anterior limbs of the internal capsule (5 features) best distinguished bmTBI from HCs with 89% accuracy. This is the first application of SVM to identify prominent features of bmTBI solely based on DTI metrics in well-defined tracts, which if successfully validated could promote targeted treatment interventions.

4.
Hum Brain Mapp ; 42(7): 1987-2004, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33449442

RESUMO

Combat-related mild traumatic brain injury (cmTBI) is a leading cause of sustained physical, cognitive, emotional, and behavioral disabilities in Veterans and active-duty military personnel. Accurate diagnosis of cmTBI is challenging since the symptom spectrum is broad and conventional neuroimaging techniques are insensitive to the underlying neuropathology. The present study developed a novel deep-learning neural network method, 3D-MEGNET, and applied it to resting-state magnetoencephalography (rs-MEG) source-magnitude imaging data from 59 symptomatic cmTBI individuals and 42 combat-deployed healthy controls (HCs). Analytic models of individual frequency bands and all bands together were tested. The All-frequency model, which combined delta-theta (1-7 Hz), alpha (8-12 Hz), beta (15-30 Hz), and gamma (30-80 Hz) frequency bands, outperformed models based on individual bands. The optimized 3D-MEGNET method distinguished cmTBI individuals from HCs with excellent sensitivity (99.9 ± 0.38%) and specificity (98.9 ± 1.54%). Receiver-operator-characteristic curve analysis showed that diagnostic accuracy was 0.99. The gamma and delta-theta band models outperformed alpha and beta band models. Among cmTBI individuals, but not controls, hyper delta-theta and gamma-band activity correlated with lower performance on neuropsychological tests, whereas hypo alpha and beta-band activity also correlated with lower neuropsychological test performance. This study provides an integrated framework for condensing large source-imaging variable sets into optimal combinations of regions and frequencies with high diagnostic accuracy and cognitive relevance in cmTBI. The all-frequency model offered more discriminative power than each frequency-band model alone. This approach offers an effective path for optimal characterization of behaviorally relevant neuroimaging features in neurological and psychiatric disorders.


Assuntos
Concussão Encefálica/diagnóstico por imagem , Concussão Encefálica/fisiopatologia , Distúrbios de Guerra/diagnóstico por imagem , Distúrbios de Guerra/fisiopatologia , Conectoma/normas , Aprendizado Profundo , Magnetoencefalografia/normas , Adulto , Conectoma/métodos , Humanos , Magnetoencefalografia/métodos , Masculino , Sensibilidade e Especificidade , Adulto Jovem
5.
Parasit Vectors ; 13(1): 19, 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31931883

RESUMO

BACKGROUND: Effective mosquito control approaches incorporate both adult and larval stages. For the latter, physical, biological, and chemical control have been used with varying results. Successful control of larvae has been demonstrated using larvicides including insect growth regulators, e.g. the organophosphate temephos, as well as various entomopathogenic microbial species. However, a variety of health and environmental issues are associated with some of these. Laboratory trials of essential oils (EO) have established the larvicidal activity of these substances, but there are currently no commercially available EO-based larvicides. Here we report on the development of a new approach to mosquito larval control using a novel, yeast-based delivery system for EO. METHODS: Food-grade orange oil (OO) was encapsulated into yeast cells following an established protocol. To prevent environmental contamination, a proprietary washing strategy was developed to remove excess EO that is adsorbed to the cell exterior during the encapsulation process. The OO-loaded yeast particles were then characterized for OO loading, and tested for efficacy against Aedes aegypti larvae. RESULTS: The composition of encapsulated OO extracted from the yeast microparticles was demonstrated not to differ from that of un-encapsulated EO when analyzed by high performance liquid chromatography. After lyophilization, the oil in the larvicide comprised 26-30 percentage weight (wt%), and is consistent with the 60-65% reduction in weight observed after the drying process. Quantitative bioassays carried with Liverpool and Rockefeller Ae. aegypti strains in three different laboratories presented LD50 of 5.1 (95% CI: 4.6-5.6) to 27.6 (95% CI: 26.4-28.8) mg/l, for L1 and L3/L4 mosquito larvae, respectively. LD90 ranged between 18.9 (95% CI: 16.4-21.7) mg/l (L1 larvae) to 76.7 (95% CI: 69.7-84.3) mg/l (L3/L4 larvae). CONCLUSIONS: The larvicide based on OO encapsulated in yeast was shown to be highly active (LD50 < 50 mg/l) against all larval stages of Ae. aegypti. These results demonstrate its potential for incorporation in an integrated approach to larval source management of Ae. aegypti. This novel approach can enable development of affordable control strategies that may have significant impact on global health.


Assuntos
Aedes/efeitos dos fármacos , Encapsulamento de Células/métodos , Controle de Mosquitos/métodos , Óleos Voláteis/farmacologia , Animais , Química Verde , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Mosquitos Vetores/efeitos dos fármacos , Óleos de Plantas/farmacologia , Saccharomyces cerevisiae
6.
Cereb Cortex ; 29(5): 1953-1968, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29668852

RESUMO

Combat-related mild traumatic brain injury (mTBI) is a leading cause of sustained cognitive impairment in military service members and Veterans. However, the mechanism of persistent cognitive deficits including working memory (WM) dysfunction is not fully understood in mTBI. Few studies of WM deficits in mTBI have taken advantage of the temporal and frequency resolution afforded by electromagnetic measurements. Using magnetoencephalography (MEG) and an N-back WM task, we investigated functional abnormalities in combat-related mTBI. Study participants included 25 symptomatic active-duty service members or Veterans with combat-related mTBI and 20 healthy controls with similar combat experiences. MEG source-magnitude images were obtained for alpha (8-12 Hz), beta (15-30 Hz), gamma (30-90 Hz), and low-frequency (1-7 Hz) bands. Compared with healthy combat controls, mTBI participants showed increased MEG signals across frequency bands in frontal pole (FP), ventromedial prefrontal cortex, orbitofrontal cortex (OFC), and anterior dorsolateral prefrontal cortex (dlPFC), but decreased MEG signals in anterior cingulate cortex. Hyperactivations in FP, OFC, and anterior dlPFC were associated with slower reaction times. MEG activations in lateral FP also negatively correlated with performance on tests of letter sequencing, verbal fluency, and digit symbol coding. The profound hyperactivations from FP suggest that FP is particularly vulnerable to combat-related mTBI.


Assuntos
Concussão Encefálica/fisiopatologia , Concussão Encefálica/psicologia , Encéfalo/fisiopatologia , Distúrbios de Guerra/patologia , Distúrbios de Guerra/fisiopatologia , Memória de Curto Prazo/fisiologia , Adulto , Concussão Encefálica/etiologia , Ondas Encefálicas , Distúrbios de Guerra/complicações , Humanos , Magnetoencefalografia , Masculino , Testes Neuropsicológicos , Veteranos
7.
Neurobiol Stress ; 9: 241-250, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30450388

RESUMO

Trauma-related disorders of affect and cognition (TRACs) are associated with a high degree of diagnostic comorbidity, which may suggest that these disorders share a set of underlying neural mechanisms. TRACs are characterized by aberrations in functional and structural circuits subserving verbal memory and affective anticipation. Yet, it remains unknown how the neural circuitry underlying these multiple mechanisms contribute to TRACs. Here, in a sample of 47 combat Veterans, we measured affective anticipation using functional magnetic resonance imaging (fMRI), verbal memory with fluorodeoxyglucose positron emission tomography (FDG-PET), and grey matter volume with structural magnetic resonance imaging (sMRI). Using a voxel-based multimodal canonical correlation analysis (mCCA), the set of neural measures were statistically integrated, or fused, with a set of TRAC symptom measures including mild traumatic brain injury (mTBI), posttraumatic stress, and depression severity. The first canonical correlation pair revealed neural convergence in clusters encompassing the middle frontal gyrus and supplemental motor area, regions implicated in top-down cognitive control and affect regulation. These results highlight the potential of leveraging multivariate neuroimaging analysis for linking neurobiological mechanisms associated with TRACs, paving the way for transdiagnostic biomarkers and targets for treatment.

8.
Front Hum Neurosci ; 12: 196, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29867419

RESUMO

Veterans with posttraumatic stress disorder (PTSD) often report suboptimal sleep quality, often described as lack of restfulness for unknown reasons. These experiences are sometimes difficult to objectively quantify in sleep lab assessments. Here, we used a streamlined sleep assessment tool to record in-home 2-channel electroencephalogram (EEG) with concurrent collection of electrodermal activity (EDA) and acceleration. Data from a single forehead channel were transformed into a whole-night spectrogram, and sleep stages were classified using a fully automated algorithm. For this study, 71 control subjects and 60 military-related PTSD subjects were analyzed for percentage of time spent in Light, Hi Deep (1-3 Hz), Lo Deep (<1 Hz), and rapid eye movement (REM) sleep stages, as well as sleep efficiency and fragmentation. The results showed a significant tendency for PTSD sleepers to spend a smaller percentage of the night in REM (p < 0.0001) and Lo Deep (p = 0.001) sleep, while spending a larger percentage of the night in Hi Deep (p < 0.0001) sleep. The percentage of combined Hi+Lo Deep sleep did not differ between groups. All sleepers usually showed EDA peaks during Lo, but not Hi, Deep sleep; however, PTSD sleepers were more likely to lack EDA peaks altogether, which usually coincided with a lack of Lo Deep sleep. Linear regressions with all subjects showed that a decreased percentage of REM sleep in PTSD sleepers was accounted for by age, prazosin, SSRIs and SNRIs (p < 0.02), while decreased Lo Deep and increased Hi Deep in the PTSD group could not be accounted for by any factor in this study (p < 0.005). Linear regression models with only the PTSD group showed that decreased REM correlated with self-reported depression, as measured with the Depression, Anxiety, and Stress Scales (DASS; p < 0.00001). DASS anxiety was associated with increased REM time (p < 0.0001). This study shows altered sleep patterns in sleepers with PTSD that can be partially accounted for by age and medication use; however, differences in deep sleep related to PTSD could not be linked to any known factor. With several medications [prazosin, selective serotonin reuptake inhibitors (SSRIs), serotonin-norepinephrine reuptake inhibitors (SNRIs); p < 0.03], as well as SSRIs were associated with less sleep efficiency (b = -3.3 ± 0.95; p = 0.0005) and more sleep fragmentation (b = -1.7 ± 0.51; p = 0.0009). Anti-psychotics were associated with less sleep efficiency (b = -4.9 ± 1.4; p = 0.0004). Sleep efficiency was negatively impacted by SSRIs, antipsychotic medications, and depression (p < 0.008). Increased sleep fragmentation was associated with SSRIs, SNRIs, and anxiety (p < 0.009), while prazosin and antipsychotic medications correlated with decreased sleep fragmentation (p < 0.05).

9.
Brain Inj ; 31(13-14): 1951-1963, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28925734

RESUMO

BACKGROUND: Mild traumatic brain injury (mTBI) is a leading cause of sustained impairments in military service members, Veterans, and civilians. However, few treatments are available for mTBI, partially because the mechanism of persistent mTBI deficits is not fully understood. METHODS: We used magnetoencephalography (MEG) to investigate neuronal changes in individuals with mTBI following a passive neurofeedback-based treatment programme called IASIS. This programme involved applying low-intensity pulses using transcranial electrical stimulation (LIP-tES) with electroencephalography monitoring. Study participants included six individuals with mTBI and persistent post-concussive symptoms (PCS). MEG exams were performed at baseline and follow-up to evaluate the effect of IASIS on brain functioning. RESULTS: At the baseline MEG exam, all participants had abnormal slow-waves. In the follow-up MEG exam, the participants showed significantly reduced abnormal slow-waves with an average reduction of 53.6 ± 24.6% in slow-wave total score. The participants also showed significant reduction of PCS scores after IASIS treatment, with an average reduction of 52.76 ± 26.4% in PCS total score. CONCLUSIONS: The present study demonstrates, for the first time, the neuroimaging-based documentation of the effect of LIP-tES treatment on brain functioning in mTBI. The mechanisms of LIP-tES treatment are discussed, with an emphasis on LIP-tES's potentiation of the mTBI healing process.


Assuntos
Lesões Encefálicas Traumáticas/diagnóstico por imagem , Lesões Encefálicas Traumáticas/terapia , Imageamento por Ressonância Magnética , Magnetoencefalografia , Estimulação Transcraniana por Corrente Contínua , Adulto , Eletroencefalografia , Feminino , Análise de Fourier , Humanos , Masculino , Testes Neuropsicológicos , Projetos Piloto , Síndrome Pós-Concussão/diagnóstico , Inquéritos e Questionários , Veteranos
10.
J Orthop Case Rep ; 7(1): 46-49, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28630839

RESUMO

INTRODUCTION: Fungal joint infection can lead to serious consequences for those affected. It can often be a delayed diagnosis due to initial negative organism growth or lack of clinician awareness. Treatment should be early and aggressive to prevent patient morbidity and mortality. CASE REPORT: We present a case of staphylococcal septic arthritis of the native hip joint with secondary superinfection by Candida albicans in a young patient with no appreciable risk factors. We explain the complexity of a delayed diagnosis and subsequent treatment. CONCLUSION: This case highlights important learning points in terms of considering secondary fungal infection in any septic arthritis patient that does not respond to conventional antimicrobial treatment.

11.
J Neurotrauma ; 34(7): 1412-1426, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-27762653

RESUMO

Blast mild traumatic brain injury (mTBI) is a leading cause of sustained impairment in military service members and veterans. However, the mechanism of persistent disability is not fully understood. The present study investigated disturbances in brain functioning in mTBI participants using a source-imaging-based approach to analyze functional connectivity (FC) from resting-state magnetoencephalography (rs-MEG). Study participants included 26 active-duty service members or veterans who had blast mTBI with persistent post-concussive symptoms, and 22 healthy control active-duty service members or veterans. The source time courses from regions of interest (ROIs) were used to compute ROI to whole-brain (ROI-global) FC for different frequency bands using two different measures: 1) time-lagged cross-correlation and 2) phase-lock synchrony. Compared with the controls, blast mTBI participants showed increased ROI-global FC in beta, gamma, and low-frequency bands, but not in the alpha band. Sources of abnormally increased FC included the: 1) prefrontal cortex (right ventromedial prefrontal cortex [vmPFC], right rostral anterior cingulate cortex [rACC]), and left ventrolateral and dorsolateral prefrontal cortex; 2) medial temporal lobe (bilateral parahippocampus, hippocampus, and amygdala); and 3) right putamen and cerebellum. In contrast, the blast mTBI group also showed decreased FC of the right frontal pole. Group differences were highly consistent across the two different FC measures. FC of the left ventrolateral prefrontal cortex correlated with executive functioning and processing speed in mTBI participants. Altogether, our findings of increased and decreased regionalpatterns of FC suggest that disturbances in intrinsic brain connectivity may be the result of multiple mechanisms, and are associated with cognitive sequelae of the injury.


Assuntos
Concussão Encefálica/fisiopatologia , Ondas Encefálicas/fisiologia , Cerebelo/fisiopatologia , Córtex Cerebral/fisiopatologia , Conectoma/métodos , Magnetoencefalografia/métodos , Militares , Putamen/fisiopatologia , Veteranos , Adulto , Tonsila do Cerebelo/fisiopatologia , Traumatismos por Explosões/complicações , Concussão Encefálica/etiologia , Função Executiva/fisiologia , Humanos , Masculino , Giro Para-Hipocampal/fisiopatologia , Síndrome Pós-Concussão/etiologia , Síndrome Pós-Concussão/fisiopatologia , Córtex Pré-Frontal/fisiopatologia , Desempenho Psicomotor/fisiologia , Estados Unidos , Adulto Jovem
12.
Am J Orthop (Belle Mead NJ) ; 45(7): E478-E480, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28005106

RESUMO

Septic arthritis is a debilitating acute orthopedic emergency. Unfortunately, the diagnosis can be delayed or missed in immunocompromised patients with diabetes mellitus, and the result can be catastrophic. These patients are also at risk for atypical infections, including mycotic subtypes, which are more insidious than their more aggressive, more common Staphylococcus counterparts. The result is increased morbidity. In this article, we report a case of Candida albicans septic arthritis in a patient with diabetes mellitus and rheumatoid arthritis. Her case highlights the complexities of this specific disease entity. With early diagnosis, treatment is multimodal, involving surgical débridement and prolonged antifungal therapy.


Assuntos
Articulação do Tornozelo/cirurgia , Artrite Infecciosa/cirurgia , Candida albicans/isolamento & purificação , Candidíase/cirurgia , Articulação do Tornozelo/microbiologia , Antifúngicos/uso terapêutico , Artrite Infecciosa/complicações , Artrite Infecciosa/tratamento farmacológico , Artrite Infecciosa/microbiologia , Artrite Reumatoide/complicações , Candidíase/complicações , Desbridamento , Diabetes Mellitus Tipo 2/complicações , Feminino , Humanos , Pessoa de Meia-Idade , Resultado do Tratamento
13.
Pain ; 157(7): 1499-1507, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26963844

RESUMO

Gabapentin is prescribed for analgesia in chronic low back pain, yet there are no controlled trials supporting this practice. This randomized, 2-arm, 12-week, parallel group study compared gabapentin (forced titration up to 3600 mg daily) with inert placebo. The primary efficacy measure was change in pain intensity from baseline to the last week on treatment measured by the Descriptor Differential Scale; the secondary outcome was disability (Oswestry Disability Index). The intention-to-treat analysis comprised 108 randomized patients with chronic back pain (daily pain for ≥6 months) whose pain did (43%) or did not radiate into the lower extremity. Random effects regression models which did not impute missing scores were used to analyze outcome data. Pain intensity decreased significantly over time (P < 0.0001) with subjects on gabapentin or placebo, reporting reductions of about 30% from baseline, but did not differ significantly between groups (P = 0.423). The same results pertained for disability scores. In responder analyses of those who completed 12 weeks (N = 72), the proportion reporting at least 30% or 50% reduction in pain intensity, or at least "Minimal Improvement" on the Physician Clinical Global Impression of Change did not differ significantly between groups. There were no significant differences in analgesia between participants with radiating (n = 46) and nonradiating (n = 62) pain either within or between treatment arms. There was no significant correlation between gabapentin plasma concentration and pain intensity. Gabapentin appears to be ineffective for analgesia in chronic low back pain with or without a radiating component.


Assuntos
Aminas/uso terapêutico , Analgésicos/uso terapêutico , Dor Crônica/tratamento farmacológico , Ácidos Cicloexanocarboxílicos/uso terapêutico , Dor Lombar/tratamento farmacológico , Ácido gama-Aminobutírico/uso terapêutico , Adulto , Idoso , Avaliação da Deficiência , Método Duplo-Cego , Feminino , Gabapentina , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Resultado do Tratamento
14.
J Neurotrauma ; 32(22): 1736-50, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25915799

RESUMO

Individuals with mild traumatic brain injury (TBI) show diminished metabolic activity when studied with positron emission tomography (PET) with (18)F-fluorodeoxyglucose (FDG). Since blast injury may not be localized in the same specific anatomical areas in every patient or may be diffuse, significance probability mapping may be vulnerable to false-negative detection of abnormalities. To address this problem, we used an anatomically independent measure to assess PET scans: increased numbers of contiguous voxels that are 2 standard deviations below values found in an uninjured control group. We examined this in three age-matched groups of male patients: 16 veterans with a history of mild TBI, 17 veterans with both mild TBI and post-traumatic stress disorder (PTSD), and 15 veterans without either condition. After FDG administration, subjects performed a modified version of the California Verbal Learning Task. Clusters of low uptake voxels were identified by computing the mean and standard deviation for each voxel in the healthy combat veteran group and then determining the voxel-based z-score for the patient groups. Abnormal clusters were defined as those that contained contiguous voxels with a z-score <-2. Patients with mild TBI alone and patients with TBI+PTSD had larger clusters of low uptake voxels, and cluster size significantly differentiated the mild TBI groups from combat controls. Clusters were more irregular in shape in patients, and patients also had a larger number of low-activity voxels throughout the brain. In mild TBI and TBI+PTSD patients, but not healthy subjects, cluster volume was significantly correlated with verbal learning during FDG uptake.


Assuntos
Lesões Encefálicas/diagnóstico por imagem , Fluordesoxiglucose F18/farmacocinética , Compostos Radiofarmacêuticos/farmacocinética , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem , Adulto , Campanha Afegã de 2001- , Tonsila do Cerebelo/diagnóstico por imagem , Lesões Encefálicas/psicologia , Análise por Conglomerados , Substância Cinzenta/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Guerra do Iraque 2003-2011 , Masculino , Testes Neuropsicológicos , Tomografia por Emissão de Pósitrons , Transtornos de Estresse Pós-Traumáticos/psicologia , Aprendizagem Verbal , Veteranos , Substância Branca/diagnóstico por imagem
15.
J Head Trauma Rehabil ; 30(2): 116-21, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24413076

RESUMO

OBJECTIVE: To evaluate the validity of the Modified Fatigue Impact Scale (MFIS) in veterans with a history of mild to moderate traumatic brain injury (TBI). PARTICIPANTS: Veterans (N = 106) with mild (92%) or moderate (8%) TBI. SETTING: Veterans Administration Health System. PROCEDURE: Factor structure, internal consistency, convergent validity, sensitivity, and specificity of the MFIS were examined. RESULTS: Principal component analysis identified 2 viable MFIS factors: a Cognitive subscale and a Physical/Activities subscale. Item analysis revealed high internal consistency of the MFIS Total scale and subscale items. Strong convergent validity of the MFIS scales was established with 2 Beck Depression Inventory II fatigue items. Receiver operating characteristic curve analysis revealed good to excellent accuracy of the MFIS in classifying fatigued versus nonfatigued individuals. CONCLUSION: The MFIS is a valid multidimensional measure that can be used to evaluate the impact of fatigue on cognitive and physical functioning in individuals with mild to moderate TBI. The psychometric properties of the MFIS make it useful for evaluating fatigue and provide the potential for improving research on fatigue in this population.


Assuntos
Lesões Encefálicas/complicações , Lesões Encefálicas/psicologia , Fadiga/diagnóstico , Fadiga/etiologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Componente Principal , Psicometria , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Inquéritos e Questionários , Veteranos , Adulto Jovem
16.
Psychiatry Res ; 224(1): 58-66, 2014 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-25150386

RESUMO

Posttraumatic stress disorder (PTSD) is common among combat personnel with mild traumatic brain injury (mTBI). While patients with either PTSD or mTBI share abnormal activation of multiple frontal brain areas, anterior cingulate cortex (ACC) activity during inhibitory processing may be particularly affected by PTSD. To further test this hypothesis, we recorded electroencephalography from 32 combat veterans with mTBI-17 of whom were also comorbid for PTSD (mTBI+PTSD) and 15 without PTSD (mTBI-only). Subjects performed the Stop Task, a validated inhibitory control task requiring inhibition of initiated motor responses. We observed a larger inhibitory processing eventrelated potential (ERP) in veterans with mTBI+PTSD, including greater N200 negativity. Furthermore, greater N200 negativity correlated with greater PTSD severity. This correlation was most dependent on contributions from the dorsal ACC. Support vector machine analysis demonstrated that N200 and P300 amplitudes objectively classified veterans into mTBI-only or mTBI+PTSD groups with 79.4% accuracy. Our results support a model where, in combat veterans with mTBI, larger ERPs from cingulate areas are associated with greater PTSD severity and likely related to difficulty controlling ongoing brain processes, including trauma-related thoughts and feelings.


Assuntos
Lesões Encefálicas/psicologia , Potenciais Evocados , Giro do Cíngulo/fisiopatologia , Transtornos de Estresse Pós-Traumáticos/psicologia , Veteranos , Adulto , Lesões Encefálicas/epidemiologia , Lesões Encefálicas/fisiopatologia , Comorbidade , Eletroencefalografia , Emoções , Feminino , Humanos , Masculino , Índice de Gravidade de Doença , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Pensamento , Estados Unidos/epidemiologia , Veteranos/psicologia , Veteranos/estatística & dados numéricos
17.
PLoS One ; 9(3): e92017, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24651705

RESUMO

BACKGROUND: Individuals with anorexia nervosa (AN) are often cognitively rigid and behaviorally over-controlled. We previously showed that adult females recovered from AN relative to healthy comparison females had less prefrontal activation during an inhibition task, which suggested a functional brain correlate of altered inhibitory processing in individuals recovered from AN. However, the degree to which these functional brain alterations are related to disease state and whether error processing is altered in AN individuals is unknown. METHODOLOGY/PRINCIPAL FINDINGS: In the current study, ill adolescent AN females (n = 11) and matched healthy comparison adolescents (CA) with no history of an eating disorder (n = 12) performed a validated stop signal task (SST) during functional magnetic resonance imaging (fMRI) to explore differences in error and inhibitory processing. The groups did not differ on sociodemographic variables or on SST performance. During inhibitory processing, a significant group x difficulty (hard, easy) interaction was detected in the right dorsal anterior cingulate cortex (ACC), right middle frontal gyrus (MFG), and left posterior cingulate cortex (PCC), which was characterized by less activation in AN compared to CA participants during hard trials. During error processing, a significant group x accuracy (successful inhibit, failed inhibit) interaction in bilateral MFG and right PCC was observed, which was characterized by less activation in AN compared to CA participants during error (i.e., failed inhibit) trials. CONCLUSION/SIGNIFICANCE: Consistent with our prior findings in recovered AN, ill AN adolescents, relative to CA, showed less inhibition-related activation within the dorsal ACC, MFG and PCC as inhibitory demand increased. In addition, ill AN adolescents, relative to CA, also showed reduced activation to errors in the bilateral MFG and left PCC. These findings suggest that altered prefrontal and cingulate activation during inhibitory and error processing may represent a behavioral characteristic in AN that is independent of the state of recovery.


Assuntos
Anorexia Nervosa/fisiopatologia , Inibição Neural/fisiologia , Oxigênio/sangue , Adolescente , Análise de Variância , Comportamento , Mapeamento Encefálico , Demografia , Feminino , Humanos , Imageamento por Ressonância Magnética , Tempo de Reação/fisiologia , Análise e Desempenho de Tarefas
18.
J Affect Disord ; 155: 234-40, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24342149

RESUMO

Posttraumatic stress disorder (PTSD) worsens prognosis following mild traumatic brain injury (mTBI). Combat personnel with histories of mTBI exhibit abnormal activation of distributed brain networks-including emotion processing and default mode networks. How developing PTSD further affects these abnormalities has not been directly examined. We recorded electroencephalography in combat veterans with histories of mTBI, but without active PTSD (mTBI only, n=16) and combat veterans who developed PTSD after mTBI (mTBI+PTSD, n=16)-during the Reading the Mind in the Eyes Test (RMET), a validated test of empathy requiring emotional appraisal of facial features. Task-related event related potentials (ERPs) were identified, decomposed using independent component analysis (ICA) and localized anatomically using dipole modeling. We observed larger emotional face processing ERPs in veterans with mTBI+PTSD, including greater N300 negativity. Furthermore, greater N300 negativity correlated with greater PTSD severity, especially avoidance/numbing and hyperarousal symptom clusters. This correlation was dependent on contributions from the precuneus and posterior cingulate cortex (PCC). Our results support a model where, in combat veterans with histories of mTBI, larger ERPs from over-active posterior-medial cortical areas may be specific to PTSD, and is likely related to negative self-referential activity.


Assuntos
Lesões Encefálicas/complicações , Distúrbios de Guerra/fisiopatologia , Potenciais Evocados/fisiologia , Giro do Cíngulo/fisiopatologia , Reconhecimento Visual de Modelos/fisiologia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Veteranos/psicologia , Distúrbios de Guerra/diagnóstico , Estudos Transversais , Eletroencefalografia , Emoções , Face , Humanos , Masculino , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Veteranos/estatística & dados numéricos
19.
Eat Behav ; 14(4): 488-92, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24183142

RESUMO

Self-report studies suggest that patients with bulimia nervosa (BN) evidence difficulties with interoceptive awareness. Indeed, interoceptive deficits may persist after recovery of BN and may be a biological trait that predisposes symptom development in BN. However, no studies to date have directly assessed interoceptive sensitivity, or accuracy in detecting and perceiving internal body cues, in patients with or recovered from BN. Nine women who had recovered from BN and 10 healthy control women completed the Heart Beat Perception Task (HBPT) in which individuals were required to estimate the number of heartbeats between intervals of time. Accuracy scores were compared between groups. Significant differences were found between the groups on the HBPT ((F1,19) = 7.78, p = .013, Cohen's d = 1.16) when controlling for age. These results suggest that deficits in interoceptive sensitivity are present in individuals recovered from BN. Thus interoceptive deficits may be one factor that bridges the gap between brain dysfunction and symptom presentation in BN.


Assuntos
Conscientização , Bulimia Nervosa/psicologia , Frequência Cardíaca , Percepção , Adolescente , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Autorrelato , Adulto Jovem
20.
Psychiatry Res ; 214(2): 132-41, 2013 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-23993362

RESUMO

Individuals with anorexia nervosa (AN) restrict food consumption and become severely emaciated. Eating food, even thinking of eating food, is often associated with heightened anxiety. However, food cue anticipation in AN is poorly understood. Fourteen women recovered from AN and 12 matched healthy control women performed an anticipation task viewing images of food and object images during functional magnetic resonance imaging. Comparing anticipation of food versus object images between control women and recovered AN groups showed significant interaction only in the right ventral anterior insula, with greater activation in recovered AN anticipating food images. These data support the hypothesis of a disconnect between anticipating and experiencing food stimuli in recovered AN. Insula activation positively correlated with pleasantness ratings of palatable foods in control women, while no such relationship existed in recovered AN, which is further evidence of altered interoceptive function. Finally, these findings raise the possibility that enhanced anterior insula anticipatory response to food cues in recovered AN could contribute to exaggerated sensitivity and anxiety related to food and eating.


Assuntos
Anorexia Nervosa , Córtex Cerebral/fisiopatologia , Alimentos , Imagens, Psicoterapia/métodos , Motivação , Recuperação de Função Fisiológica/fisiologia , Adolescente , Adulto , Anorexia Nervosa/patologia , Anorexia Nervosa/psicologia , Anorexia Nervosa/terapia , Mapeamento Encefálico , Córtex Cerebral/irrigação sanguínea , Sinais (Psicologia) , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Modelos Lineares , Imageamento por Ressonância Magnética , Oxigênio/sangue , Prazer , Fatores de Tempo , Adulto Jovem
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