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1.
J Chin Polit Sci ; 28(1): 151-167, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35693300

RESUMO

As China's global footprint expands and Sino-American competition intensifies, it is apparent that one of the most important arenas for competition between Western Liberal norms and Chinese Communist Party's (CCP) authoritarian norms is going to come in competing technologies (Western/Korean/Taiwanese 5G/chips vs Huawei 5G/chips) and competing cyber-norms (Western cyber-libertarianism vs Chinese cyber-sovereignty). Inside China, China's technologies and its cyber-sovereign norms converge.Outside of China, while China champions the norm of cyber-sovereignty, Huawei itself may pose the greatest challenge to sovereign states' cyber-sovereignty where Huawei controls or otherwise participates significantly as a provider for telecommunications networks, given its relationship to the Chinese state. Is China sincere in advocating cyber-sovereignty as an international norm, or is this just something it is concerned about inside China?Are the laws of China and the technologies and practices of its own Huawei antithetical to China's own stated norms of cyber-sovereignty? Is cyber-sovereignty simply a stop-gap measure adopted by an insecure regime to justify draconian censorship and thought control at home while it seeks to use its growing presence in 5G telecommunications to expand its surveillance of foreign powers/actors worldwide? Finally, in keeping with the theme of this special issue, does digital orientalism explain the growing tension between China and some of the Western/Liberal powers as it regards competition in 5G? Is the US/West needlessly securitizing Huawei and its 5G, or is there something there worth securitizing? Clarity about these issues and the implications of the answers arrived at are important for nations around the world as China expands its technological reach via Huawei and other national champions.

2.
BMC Med Inform Decis Mak ; 18(1): 32, 2018 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-29843696

RESUMO

BACKGROUND: Genomic medicine is emerging into clinical care. Communication of genetic laboratory results to patients and providers is hampered by the complex technical nature of the laboratory reports. This can lead to confusion and misinterpretation of the results resulting in inappropriate care. Patients usually do not receive a copy of the report leading to further opportunities for miscommunication. To address these problems, interpretive reports were created using input from the intended end users, patients and providers. This paper describes the technical development and deployment of the first patient-facing genomic test report (PGR) within an electronic health record (EHR) ecosystem using a locally developed standards-based web-application interface. METHODS: A patient-facing genomic test report with a companion provider report was configured for implementation within the EHR using a locally developed software platform, COMPASS™. COMPASS™ is designed to manage secure data exchange, as well as patient and provider access to patient reported data capture and clinical display tools. COMPASS™ is built using a Software as a Service (SaaS) approach which exposes an API that apps can interact with. RESULTS: An authoring tool was developed that allowed creation of patient-specific PGRs and the accompanying provider reports. These were converted to a format that allowed them to be presented in the patient portal and EHR respectively using the existing COMPASS™ interface thus allowing patients, caregivers and providers access to individual reports designed for the intended end user. CONCLUSIONS: The PGR as developed was shown to enhance patient and provider communication around genomic results. It is built on current standards but is designed to support integration with other tools and be compatible with emerging opportunities such as SMART on FHIR. This approach could be used to support genomic return of results as the tool is scalable and generalizable.


Assuntos
Revelação , Registros Eletrônicos de Saúde , Testes Genéticos , Aplicações da Informática Médica , Acesso dos Pacientes aos Registros , Relações Profissional-Paciente , Humanos
3.
NPJ Digit Med ; 1: 9, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-31304294

RESUMO

Intracranial hemorrhage (ICH) requires prompt diagnosis to optimize patient outcomes. We hypothesized that machine learning algorithms could automatically analyze computed tomography (CT) of the head, prioritize radiology worklists and reduce time to diagnosis of ICH. 46,583 head CTs (~2 million images) acquired from 2007-2017 were collected from several facilities across Geisinger. A deep convolutional neural network was trained on 37,074 studies and subsequently evaluated on 9499 unseen studies. The predictive model was implemented prospectively for 3 months to re-prioritize "routine" head CT studies as "stat" on realtime radiology worklists if an ICH was detected. Time to diagnosis was compared between the re-prioritized "stat" and "routine" studies. A neuroradiologist blinded to the study reviewed false positive studies to determine whether the dictating radiologist overlooked ICH. The model achieved an area under the ROC curve of 0.846 (0.837-0.856). During implementation, 94 of 347 "routine" studies were re-prioritized to "stat", and 60/94 had ICH identified by the radiologist. Five new cases of ICH were identified, and median time to diagnosis was significantly reduced (p < 0.0001) from 512 to 19 min. In particular, one outpatient with vague symptoms on anti-coagulation was found to have an ICH which was treated promptly with reversal of anticoagulation, resulting in a good clinical outcome. Of the 34 false positives, the blinded over-reader identified four probable ICH cases overlooked in original interpretation. In conclusion, an artificial intelligence algorithm can prioritize radiology worklists to reduce time to diagnosis of new outpatient ICH by 96% and may also identify subtle ICH overlooked by radiologists. This demonstrates the positive impact of advanced machine learning in radiology workflow optimization.

4.
Radiology ; 284(3): 862-869, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28448234

RESUMO

Purpose To validate the use of thick-section clinically acquired magnetic resonance (MR) imaging data for estimating total brain volume (TBV), gray matter (GM) volume (GMV), and white matter (WM) volume (WMV) by using three widely used automated toolboxes: SPM ( www.fil.ion.ucl.ac.uk/spm/ ), FreeSurfer ( surfer.nmr.mgh.harvard.edu ), and FSL (FMRIB software library; Oxford Centre for Functional MR Imaging of the Brain, Oxford, England, https://fsl.fmrib.ox.ac.uk/fsl ). Materials and Methods MR images from a clinical archive were used and data were deidentified. The three methods were applied to estimate brain volumes from thin-section research-quality brain MR images and routine thick-section clinical MR images acquired from the same 38 patients (age range, 1-71 years; mean age, 22 years; 11 women). By using these automated methods, TBV, GMV, and WMV were estimated. Thin- versus thick-section volume comparisons were made for each method by using intraclass correlation coefficients (ICCs). Results SPM exhibited excellent ICCs (0.97, 0.85, and 0.83 for TBV, GMV, and WMV, respectively). FSL exhibited ICCs of 0.69, 0.51, and 0.60 for TBV, GMV, and WMV, respectively, but they were lower than with SPM. FreeSurfer exhibited excellent ICC of 0.63 only for TBV. Application of SPM's voxel-based morphometry on the modulated images of thin-section images and interpolated thick-section images showed fair to excellent ICCs (0.37-0.98) for the majority of brain regions (88.47% [306924 of 346916 voxels] of WM and 80.35% [377 282 of 469 502 voxels] of GM). Conclusion Thick-section clinical-quality MR images can be reliably used for computing quantitative brain metrics such as TBV, GMV, and WMV by using SPM. © RSNA, 2017 Online supplemental material is available for this article.


Assuntos
Encéfalo/anatomia & histologia , Encéfalo/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Reprodutibilidade dos Testes , Adulto Jovem
5.
EGEMS (Wash DC) ; 5(1): 23, 2017 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-29930964

RESUMO

INTRODUCTION: Reducing misdiagnosis has long been a goal of medical informatics. Current thinking has focused on achieving this goal by integrating diagnostic decision support into electronic health records. METHODS: A diagnostic decision support system already in clinical use was integrated into electronic health record systems at two large health systems, after clinician input on desired capabilities. The decision support provided three outputs: editable text for use in a clinical note, a summary including the suggested differential diagnosis with a graphical representation of probability, and a list of pertinent positive and pertinent negative findings (with onsets). RESULTS: Structured interviews showed widespread agreement that the tool was useful and that the integration improved workflow. There was disagreement among various specialties over the risks versus benefits of documenting intermediate diagnostic thinking. Benefits were most valued by specialists involved in diagnostic testing, who were able to use the additional clinical context for richer interpretation of test results. Risks were most cited by physicians making clinical diagnoses, who expressed concern that a process that generated diagnostic possibilities exposed them to legal liability. DISCUSSION AND CONCLUSION: Reconciling the preferences of the various groups could include saving only the finding list as a patient-wide resource, saving intermediate diagnostic thinking only temporarily, or adoption of professional guidelines to clarify the role of decision support in diagnosis.

6.
Front Neurosci ; 10: 522, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27994534

RESUMO

Voxel based morphometry (VBM) is a widely utilized neuroimaging technique for spatially normalizing brain structural MRI (sMRI) onto a common template. The DARTEL technique of VBM takes into account the spatial intensity distribution of sMRIs to construct a study specific group template. The group template is then used to create final individual normalized tissue maps (FINTM) for each subject in the group. In this study, we investigate the effect of group on FINTM, i.e., we evaluate the variability of a constant subject's FINTM when other subjects in the group are iteratively changed. We examine this variability under the following scenarios: (1) when the demographics of the iterative groups are similar, (2) when the average age of the iterative groups is increased, and (3) when the number of subjects with a brain disorder (here we use subjects with autism) is increased. Our results show that when subject demographics of the group remains similar the mean standard deviation (SD) of FINTM gray matter (GM) of the constant subject was around 0.01. As the average age of the group is increased, mean SD of GM increased to around 0.03 and at certain brain locations variability was as high as 0.23. A similar increase in variability was observed when the number of autism subjects in the group was increased where mean SD was around 0.02. Further, we find that autism vs. control GM differences are in the range of -0.05 to +0.05 for more than 97% of the voxels and note that the magnitude of the differences are comparable to GM variability. Finally, we report that opting not to modulate during normalization or increasing the size of the smoothing kernel can decrease FINTM variability but at the loss of subject-specific features. Based on the findings of this study, we outline precautions that should be considered by investigators to reduce the impact of group on FINTM and thereby derive more meaningful group differences when comparing two cohorts of subjects.

7.
Front Neurosci ; 10: 439, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27746713

RESUMO

Previous studies applying automatic preprocessing methods on Structural Magnetic Resonance Imaging (sMRI) report inconsistent neuroanatomical abnormalities in Autism Spectrum Disorder (ASD). In this study we investigate inter-method differences as a possible cause behind these inconsistent findings. In particular, we focus on the estimation of the following brain volumes: gray matter (GM), white matter (WM), cerebrospinal fluid (CSF), and total intra cranial volume (TIV). T1-weighted sMRIs of 417 ASD subjects and 459 typically developing controls (TDC) from the ABIDE dataset were estimated using three popular preprocessing methods: SPM, FSL, and FreeSurfer (FS). Brain volumes estimated by the three methods were correlated but had significant inter-method differences; except TIVSPM vs. TIVFS, all inter-method differences were significant. ASD vs. TDC group differences in all brain volume estimates were dependent on the method used. SPM showed that TIV, GM, and CSF volumes of ASD were larger than TDC with statistical significance, whereas FS and FSL did not show significant differences in any of the volumes; in some cases, the direction of the differences were opposite to SPM. When methods were compared with each other, they showed differential biases for autism, and several biases were larger than ASD vs. TDC differences of the respective methods. After manual inspection, we found inter-method segmentation mismatches in the cerebellum, sub-cortical structures, and inter-sulcal CSF. In addition, to validate automated TIV estimates we performed manual segmentation on a subset of subjects. Results indicate that SPM estimates are closest to manual segmentation, followed by FS while FSL estimates were significantly lower. In summary, we show that ASD vs. TDC brain volume differences are method dependent and that these inter-method discrepancies can contribute to inconsistent neuroimaging findings in general. We suggest cross-validation across methods and emphasize the need to develop better methods to increase the robustness of neuroimaging findings.

8.
Behav Brain Res ; 315: 141-6, 2016 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-27555534

RESUMO

Schizophrenia represents the extreme end of a distribution of traits that extends well into the general population. Using a recently developed measure of psychotic-like traits in children, we examined the neural substrates of psychotic (and other psychiatric) symptoms using structural magnetic resonance imaging (MRI). Twenty-eight typically-developing children (14 males) between the ages of 6-17 years underwent a 3T MRI scan. Parents completed the Psychiatric and Schizotypal Inventory for Children. Results revealed that caudate, amygdala, hippocampal and middle temporal gyrus volumes were associated with quantitative dimensions of psychiatric traits. Furthermore, results suggest a differential a sexually-dimorphic pattern of brain-schizotypy associations. These findings highlight brain-behavior continuities between clinical conditions such as schizophrenia and normal trait variation in typical development.


Assuntos
Mapeamento Encefálico , Encéfalo/diagnóstico por imagem , Encéfalo/crescimento & desenvolvimento , Transtorno da Personalidade Esquizotípica/diagnóstico por imagem , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Oxigênio/sangue
9.
Neurosurgery ; 78(1): 62-70, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26348013

RESUMO

BACKGROUND: The estimated prevalence of lumbar or sacral transitional vertebrae (LSTV) in the population is 4% to 30%. Few small patient series have studied the normal level of the conus medullaris (CM) in individuals with LSTV. OBJECTIVE: To determine, by using a large cohort of patients, whether individuals of all ages with LSTV have different CM positions in the spinal canal in comparison with the rest of the population with normal vertebral columns. METHODS: We performed an institutional retrospective analysis of spinal magnetic resonance images on individuals with LSTV of all ages, sexes, and pathologies during a 10-year period. Fifty-seven percent of patients (n = 467) had a lumbarized vertebra and 43% had sacralized vertebra (n = 355). Mean age at the time of the study was 55 ± 19 years (range 1-97 years). Fifty-two percent were male and 48% were female. Sixty percent of subjects with a sacralized vertebra were female, and 54.5% of those with a lumbarized vertebra were male (P = .001). RESULTS: The CM in individuals with a lumbarized vertebra was seen to be lower at L1-2 to L2s, than un those with a sacralized vertebra where most conuses were at T12-L1 to L1s (P ≤ 0.001). The CM level was similarly distributed among sexes and ages. CONCLUSION: In our series, the CM level, when lumbarization occurred, was lower, with a mean level at L1-L2, whereas a more superior mean level at T12-L1 was seen when sacralization occurred. CM level was not influenced by sex, age, or pathology other than tethered cords.


Assuntos
Vértebras Lombares/patologia , Sacro/patologia , Medula Espinal/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Defeitos do Tubo Neural/patologia , Estudos Retrospectivos , Adulto Jovem
10.
Neuropsychol Rev ; 26(1): 25-43, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26482248

RESUMO

ASD and ADHD are regarded as distinct disorders in the current DSM-5. However, recent research and the RDoC initiative are recognizing considerable overlap in the clinical presentation of ASD, ADHD, and other neurodevelopmental disorders. In spite of numerous neuroimaging findings in ASD and ADHD, the extent to which either of the above views are supported remains equivocal. Here we compare structural MRI and DTI literature in ASD and ADHD. Our main findings reveal both distinct and shared neural features. Distinct expressions were in total brain volume (ASD: increased volume, ADHD: decreased volume), amygdala (ASD: overgrowth, ADHD: normal), and internal capsule (ASD: unclear, ADHD: reduced FA in DTI). Considerable overlap was noted in the corpus callosum and cerebellum (lower volume in structural MRI and decreased FA in DTI), and superior longitudinal fasciculus (reduced FA in DTI). In addition, we identify brain regions which have not been studied in depth and require more research. We discuss relationships between brain features and symptomatology. We conclude by addressing limitations of current neuroimaging research and offer approaches that account for clinical heterogeneity to better distinguish brain-behavior relationships.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/patologia , Transtorno do Espectro Autista/patologia , Encéfalo/patologia , Imagem de Tensor de Difusão , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino
11.
Brain Imaging Behav ; 9(2): 264-74, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24788335

RESUMO

The social-cognitive deficits associated with several neurodevelopmental and neuropsychiatric disorders have been linked to structural and functional brain anomalies. Given the recent appreciation for quantitative approaches to behavior, in this study we examined the brain-behavior links in social cognition in healthy young adults from a quantitative approach. Twenty-two participants were administered quantitative measures of social cognition, including the social responsiveness scale (SRS), the empathizing questionnaire (EQ) and the systemizing questionnaire (SQ). Participants underwent a structural, 3-T magnetic resonance imaging (MRI) procedure that yielded both volumetric (voxel count) and asymmetry indices. Model fitting with backward elimination revealed that a combination of cortical, limbic and striatal regions accounted for significant variance in social behavior and cognitive styles that are typically associated with neurodevelopmental and neuropsychiatric disorders. Specifically, as caudate and amygdala volumes deviate from the typical R > L asymmetry, and cortical gray matter becomes more R > L asymmetrical, overall SRS and Emotion Recognition scores increase. Social Avoidance was explained by a combination of cortical gray matter, pallidum (rightward asymmetry) and caudate (deviation from rightward asymmetry). Rightward asymmetry of the pallidum was the sole predictor of Interpersonal Relationships and Repetitive Mannerisms. Increased D-scores on the EQ-SQ, an indication of greater systemizing relative to empathizing, was also explained by deviation from the typical R > L asymmetry of the caudate.These findings extend the brain-behavior links observed in neurodevelopmental disorders to the normal distribution of traits in a healthy sample.


Assuntos
Encéfalo/anatomia & histologia , Cognição , Habilidades Sociais , Feminino , Substância Cinzenta/anatomia & histologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Modelos Neurológicos , Tamanho do Órgão , Testes Psicológicos , Inquéritos e Questionários , Adulto Jovem
12.
Behav Brain Res ; 263: 1-8, 2014 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-24462962

RESUMO

BACKGROUND: Social cognition is an important aspect of social behavior in humans. Social cognitive deficits are associated with neurodevelopmental and neuropsychiatric disorders. In this study we examine the neural substrates of social cognition and face processing in a group of healthy young adults to examine the neural substrates of social cognition. METHODS: Fifty-seven undergraduates completed a battery of social cognition tasks and were assessed with electroencephalography (EEG) during a face-perception task. A subset (N=22) were administered a face-perception task during functional magnetic resonance imaging. RESULTS: Variance in the N170 EEG was predicted by social attribution performance and by a quantitative measure of empathy. Neurally, face processing was more bilateral in females than in males. Variance in fMRI voxel count in the face-sensitive fusiform gyrus was predicted by quantitative measures of social behavior, including the Social Responsiveness Scale (SRS) and the Empathizing Quotient. CONCLUSIONS: When measured as a quantitative trait, social behaviors in typical and pathological populations share common neural pathways. The results highlight the importance of viewing neurodevelopmental and neuropsychiatric disorders as spectrum phenomena that may be informed by studies of the normal distribution of relevant traits in the general population.


Assuntos
Encéfalo/fisiologia , Face , Percepção Social , Percepção Visual/fisiologia , Adolescente , Encéfalo/crescimento & desenvolvimento , Encéfalo/fisiopatologia , Eletroencefalografia , Empatia/fisiologia , Potenciais Evocados Visuais , Feminino , Lateralidade Funcional , Humanos , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/crescimento & desenvolvimento , Vias Neurais/fisiologia , Vias Neurais/fisiopatologia , Testes Neuropsicológicos , Lobo Occipital/fisiologia , Estimulação Luminosa , Fatores Sexuais , Lobo Temporal/fisiologia , Fatores de Tempo , Adulto Jovem
13.
J Clin Invest ; 123(4): 1809-20, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23478409

RESUMO

Maple syrup urine disease (MSUD) is an inherited disorder of branched chain amino acid metabolism presenting with neonatal encephalopathy, episodic metabolic decompensation, and chronic amino acid imbalances. Dietary management enables survival and reduces risk of acute crises. Liver transplantation has emerged as an effective way to eliminate acute decompensation risk. Psychiatric illness is a reported MSUD complication, but has not been well characterized and remains poorly understood. We report the prevalence and characteristics of neuropsychiatric problems among 37 classical MSUD patients (ages 5-35 years, 26 on dietary therapy, 11 after liver transplantation) and explore their underlying mechanisms. Compared with 26 age-matched controls, MSUD patients were at higher risk for disorders of cognition, attention, and mood. Using quantitative proton magnetic resonance spectroscopy, we found lower brain glutamate, N-acetylaspartate (NAA), and creatine concentrations in MSUD patients, which correlated with specific neuropsychiatric outcomes. Asymptomatic neonatal course and stringent longitudinal biochemical control proved fundamental to optimizing long-term mental health. Neuropsychiatric morbidity and neurochemistry were similar among transplanted and nontransplanted MSUD patients. In conclusion, amino acid dysregulation results in aberrant neural networks with neurochemical deficiencies that persist after transplant and correlate with neuropsychiatric morbidities. These findings may provide insight into general mechanisms of psychiatric illness.


Assuntos
Ácido Aspártico/análogos & derivados , Encéfalo/metabolismo , Ácido Glutâmico/metabolismo , Doença da Urina de Xarope de Bordo/psicologia , Adolescente , Adulto , Afeto , Ansiedade/epidemiologia , Ansiedade/etiologia , Ansiedade/metabolismo , Ácido Aspártico/metabolismo , Atenção , Estudos de Casos e Controles , Criança , Pré-Escolar , Creatina/metabolismo , Depressão/epidemiologia , Depressão/etiologia , Depressão/metabolismo , Feminino , Humanos , Comportamento Impulsivo/epidemiologia , Comportamento Impulsivo/etiologia , Comportamento Impulsivo/metabolismo , Transplante de Fígado , Masculino , Doença da Urina de Xarope de Bordo/epidemiologia , Doença da Urina de Xarope de Bordo/metabolismo , Doença da Urina de Xarope de Bordo/terapia , Prevalência , Agitação Psicomotora/epidemiologia , Agitação Psicomotora/etiologia , Agitação Psicomotora/metabolismo , Risco , Adulto Jovem
14.
Radiology ; 262(1): 216-23, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22069156

RESUMO

PURPOSE: To compare the relative incidence, distribution, and radiologic characteristics of spinal subdural hemorrhage after abusive head trauma versus that after accidental trauma in children. MATERIALS AND METHODS: This study received prior approval from the Human Subjects Protection Office. Informed consent was waived. This study was HIPAA compliant. Two hundred fifty-two children aged 0-2 years treated for abusive head trauma at our institute between 1997 and 2009 were identified through retrospective chart review. A second group of 70 children aged 0-2 years treated at our institute for well-documented accidental trauma between 2003 and 2010 were also identified through retrospective chart review. All clinical data and cross-sectional imaging results, including computed tomographic and magnetic resonance imaging of the brain, spine, chest, abdomen, and pelvis, were reviewed for both of these groups. A Fisher exact test was performed to assess the statistical significance of the proportion of the spinal canal subdural hemorrhage in abusive head trauma versus that in accidental trauma. RESULTS: In the abusive head trauma cohort, 67 (26.5%) of 252 children had evaluable spinal imaging results. Of these, 38 (56%) of 67 children had undergone thoracolumbar imaging, and 24 (63%) of 38 had thoracolumbar subdural hemorrhage. Spinal imaging was performed in this cohort 0.3-141 hours after injury (mean, 23 hours ± 27 [standard deviation]), with 65 (97%) of 67 cases having undergone imaging within 52 hours of injury. In the second cohort with accidental injury, only one (1%) of 70 children had spinal subdural hemorrhage at presentation; this patient had displaced occipital fracture. The comparison of incidences of spinal subdural hemorrhage in abusive head trauma versus those in accidental trauma was statistically significant (P < .001). CONCLUSION: Spinal canal subdural hemorrhage was present in more than 60% of children with abusive head trauma who underwent thoracolumbar imaging in this series but was rare in those with accidental trauma.


Assuntos
Acidentes , Maus-Tratos Infantis , Traumatismos Craniocerebrais/diagnóstico , Hematoma Subdural/diagnóstico , Traumatismos da Coluna Vertebral/diagnóstico , Traumatismos Craniocerebrais/epidemiologia , Feminino , Hematoma Subdural/epidemiologia , Humanos , Incidência , Lactente , Recém-Nascido , Imageamento por Ressonância Magnética/métodos , Masculino , Pennsylvania/epidemiologia , Estudos Retrospectivos , Traumatismos da Coluna Vertebral/epidemiologia , Tomografia Computadorizada por Raios X/métodos
15.
Physiol Behav ; 99(4): 445-50, 2010 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-20006966

RESUMO

Risk-taking behaviors involve increased motor activity and reduced anxiety in humans. Total sleep deprivation (SD) in animals produces a similar change in motor and fear behaviors. Investigators studied region-specific brain levels of glutamate in rats after TSD, an animal model of risk-taking behavior. We investigated the effects of sleep deprivation on these behaviors and associated levels of brain glutamate. Compared to the controls, the sleep-deprived rats spent a significantly greater percentage of time in the open arms of the elevated plus maze (EPM), demonstrating reduced fear-like and increased risk-taking behaviors. Additionally, sleep deprivation was associated with a significant increase in glutamate levels in the hippocampus and thalamus. An inverse relationship between glutamate in the medial prefrontal cortex and risk taking in the EPM and a positive association between the ratio of glutamate in the hippocampus to medial prefrontal cortex and risk taking was revealed. The role of sleep deprivation-induced changes in brain glutamate and its relationship to anxiety, fear, and posttraumatic stress disorder (PTSD) is discussed.


Assuntos
Encéfalo/metabolismo , Ácido Glutâmico/metabolismo , Assunção de Riscos , Animais , Comportamento Animal/fisiologia , Encéfalo/anatomia & histologia , Cromatografia Líquida de Alta Pressão/métodos , Espectroscopia de Ressonância Magnética/métodos , Masculino , Aprendizagem em Labirinto/fisiologia , Ratos , Ratos Sprague-Dawley , Privação do Sono/patologia , Privação do Sono/fisiopatologia , Estatística como Assunto/métodos , Trítio
16.
J Clin Psychiatry ; 70(5): 699-705, 2009 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-19389332

RESUMO

OBJECTIVE: Recent molecular, preclinical, and preliminary clinical studies suggest that the therapeutic effects of mood stabilizers may be mediated by modulating expression of potent neurotrophic and neuroprotective factors having the potential to reverse impairments of cellular resilience, reductions in brain volume, and cell death or atrophy. Our main goal was to investigate the potential clinical significance of these findings in relation to bipolar disorder. METHOD: The longitudinal effect of lithium on brain gray matter volume was investigated in well-characterized (DSM-IV criteria) bipolar depressed subjects (N = 28) at baseline (medication-free) and after lithium administration (4 weeks). Total brain gray matter, prefrontal gray matter, and left subgenual prefrontal gray matter volumes were determined using validated semiautomated segmentation and region of interest methodology. The study was conducted from November 1997 until April 2004 at Wayne State University School of Medicine, Detroit, Mich. RESULTS: Significant increases in total brain gray matter volume in bipolar subjects were observed after 4 weeks of lithium administration (p = .0043). Moreover, regional analyses in the bipolar subjects revealed significant differences between responders (>50% decrease in Hamilton Depression Rating Scale total score) and nonresponders; only responders showed a significant increase in gray matter volume in the prefrontal cortex (p = .003) and an increase at trend level in the left subgenual prefrontal cortex volume (p = .0786). CONCLUSION: The increase in gray matter volume in these areas, which various neuroimaging and postmortem neuropathology studies have implicated in the neuropathophysiology of bipolar disorder, suggests that the observed effects may be linked to clinical response. The findings also support the notion that future treatments that more directly target molecules in critical central nervous system pathways that regulate cellular plasticity hold promise as novel, improved, long-term treatments for mood disorders as well as some neurodegenerative conditions, such as Alzheimer's disease. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00870311.


Assuntos
Antimaníacos/farmacologia , Antimaníacos/uso terapêutico , Transtorno Bipolar/tratamento farmacológico , Transtorno Bipolar/fisiopatologia , Carbonato de Lítio/farmacologia , Carbonato de Lítio/uso terapêutico , Córtex Pré-Frontal , Adulto , Transtorno Bipolar/diagnóstico , Manual Diagnóstico e Estatístico de Transtornos Mentais , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Córtex Pré-Frontal/anatomia & histologia , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/fisiopatologia , Índice de Gravidade de Doença , Inquéritos e Questionários , Adulto Jovem
17.
Psychiatry Res ; 164(1): 86-9, 2008 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-18703320

RESUMO

The medial temporal cortex (MTC) has been implicated in the pathogenesis of pediatric major depressive disorder (MDD). Eleven MDD case-control pairs underwent proton magnetic resonance spectroscopic imaging. N-acetyl-aspartate was lower in the left MTC (27%) in MDD patients versus controls. Lower N-acetyl-aspartate concentrations in MDD patients may reflect reduced neuronal viability.


Assuntos
Ácido Aspártico/análogos & derivados , Transtorno Depressivo Maior/metabolismo , Adolescente , Ácido Aspártico/metabolismo , Criança , Colina/metabolismo , Creatina/metabolismo , Feminino , Humanos , Masculino
18.
Biol Psychiatry ; 63(4): 385-90, 2008 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-17640621

RESUMO

BACKGROUND: Abnormalities in the amygdala and hippocampus have been implicated in the pathogenesis of major depressive disorder (MDD). To our knowledge, no prior study has examined amygdala-hippocampus anatomy in pediatric patients with familial MDD (at least one first degree relative with MDD). METHODS: Thirty-two psychotropic-naive patients with familial MDD, aged 8-21 years (12 males and 20 females), and 35 group-matched healthy participants (13 males and 22 females) underwent volumetric magnetic resonance imaging in order to evaluate hippocampal and amygdala volumes. RESULTS: Patients with familial MDD had significantly smaller left hippocampal (p = .007, effect size [d] = .44) and right hippocampal volumes (p = .025, d = .33) than controls. No differences were noted in amygdala volumes between groups (right: p > .05, left: p > .05). No correlations between hippocampal or amygdala volumes and demographic or clinical variables were noted. CONCLUSIONS: Reduced hippocampal volume may be suggestive of a risk factor for developing MDD.


Assuntos
Tonsila do Cerebelo/anatomia & histologia , Transtorno Depressivo Maior/genética , Hipocampo/anatomia & histologia , Imageamento por Ressonância Magnética , Adolescente , Adulto , Idade de Início , Tonsila do Cerebelo/fisiopatologia , Criança , Transtorno Depressivo Maior/epidemiologia , Feminino , Hipocampo/fisiopatologia , Humanos , Masculino , Fatores de Tempo
19.
Life Sci ; 80(10): 940-4, 2007 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-17174342

RESUMO

The pituitary gland plays a central role in sexual development and brain function. Therefore, we examined the effect of age and gender on pituitary volume in a large sample of healthy children and adults. Volumetric magnetic resonance imaging (MRI) was conducted in one hundred and fifty four (77 males and 77 females) healthy participants. Males were between the ages of 7 to 35 years (16.91+/-5.89 years) and females were 7 to 35 years of age (16.75+/-5.75 years). Subjects were divided into subgroups of age (7 to 9, 10 to 13, 14 to 17, 18 to 21, 22 and older) and sex (male/female). Pituitary gland volume differed between sexes when comparing the age groups (F=3.55, df=2, 143, p=0.03). Females demonstrated larger pituitary glands than males in the age 14 to 17 year old groups (p=0.04). Young (19 years and under) and old (20 years and older) females demonstrated a correlation between pituitary volume and age. Males did not show this relationship. These findings provide additional evidence for gender differences in the normative anatomy of the pituitary and may have relevance for the study of various childhood onset neuropsychiatric disorders in which pituitary dysfunction has been implicated.


Assuntos
Hipófise/crescimento & desenvolvimento , Adolescente , Adulto , Envelhecimento/fisiologia , Criança , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Hipófise/anatomia & histologia , Hipófise/fisiologia , Caracteres Sexuais
20.
Neurotoxicol Teratol ; 28(5): 597-606, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16996247

RESUMO

Magnetic resonance imaging (MRI) and magnetic resonance spectroscopic imaging (MRSI) offer unique, noninvasive methods of measuring, respectively, in vivo quantitative neuroanatomy and neurochemistry. The main purpose of the present study was to identify and compare the neuroanatomical and neurochemical abnormalities that are associated with prenatal exposure to alcohol in both fetal alcohol syndrome (FAS)-diagnosed children and those diagnosed with fetal alcohol effects (FAE). MR data of three age-, gender- and race-balanced groups of children, FAS-diagnosed, FAE-diagnosed and non-exposed controls, were compared. Effects of prenatal alcohol exposure, regardless of diagnosis, were found in the caudate nucleus. Specifically, a significantly smaller caudate nucleus was found for the FAS and FAE participants compared to the controls. In addition, the metabolite ratio of N-acetyl-aspartate to creatine (NAA/Cr), an indicator of neuronal function, in left caudate nucleus of both the FAS and FAE participants was elevated compared to the control group. Analysis of absolute concentrations revealed that the increase in the ratio of NAA/Cr was due to an increase in NAA alone. Although its exact function in the CNS is unknown, NAA is believed to be a neuronal marker due to its exclusive localization to neurons. Some also speculate a role for NAA in myelination. Elevated NAA in the prenatal alcohol-exposed participants could indicate a lack of normal program cell death, dendritic pruning and/or myelination during development. The present study demonstrates that prenatal alcohol-exposed children, with or without facial dysmorphology, have abnormal brain anatomy and chemistry.


Assuntos
Núcleo Caudado/patologia , Etanol/farmacologia , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Efeitos Tardios da Exposição Pré-Natal/patologia , Mapeamento Encefálico , Criança , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente
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