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1.
Pathologica ; 107(3-4): 181-4, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26946873

RESUMO

We report the unusual case of a plexiform fibromyxoma, occasionally assessed in a lithiasic gallbladder. The full thickness assessment of the gallbladder wall revealed an intra-mural, well demarked multi-nodular tumor (1 cm), consisting of a plexiform growth of spindle cells, included within a fibromyxoid stroma with a rich micro-vascular network. The tumor cells featured no nuclear atypia, nor mitotic activity. At the immunohistochemical profiling, the spindle shaped cells unequivocally featured vimentin, SMA, HHF35, collagen IV, and CD34; no cells expressed CD117, PDGFRA, CD10, desmin, GFAP, EMA, and S-100. Faint STAT6 nuclear expression was observed in isolated tumor cells. The molecular profiling did not revealed any CKIT and PDGFRA genes mutations. The uncommon site of the tumor presentation and its aberrant CD34 expression both confer to the reported case a unique place among the myxoid tumors of the gastrointestinal tract.


Assuntos
Fibroma/patologia , Neoplasias da Vesícula Biliar/patologia , Vesícula Biliar/patologia , Feminino , Humanos , Pessoa de Meia-Idade
2.
Neuroimage ; 31(3): 1306-14, 2006 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-16545581

RESUMO

We used blood oxygen-dependent (BOLD) fMRI technique at 1.5 T to examine brain regions associated with language comprehension in normally developing children, age 5 to 10 years. Twenty-three children participated in the study using an auditory semantic decision task which varied in task difficulty. Analysis of individual participants' data showed patterns of activation largely consistent with previous neuroimaging findings in adult language processing. Group data analysis also showed a strong left-lateralized pattern of activation that closely resembles those typically observed in adults. In addition, significant activation in the left fusiform gyrus was observed and was associated with task accuracy. This finding suggests that auditory semantic processing in young children may recruit cortical regions associated with word reading in adults prior to the initiation of a semantic category decision, a process which is consistent with patterns of early word recognition process and language development.


Assuntos
Córtex Cerebral/fisiologia , Dominância Cerebral/fisiologia , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Oxigênio/sangue , Leitura , Semântica , Percepção da Fala/fisiologia , Fatores Etários , Mapeamento Encefálico , Criança , Pré-Escolar , Tomada de Decisões/fisiologia , Feminino , Lobo Frontal/fisiologia , Humanos , Masculino , Córtex Motor/fisiologia , Testes Neuropsicológicos , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia
3.
Neurology ; 65(10): 1604-11, 2005 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-16301489

RESUMO

OBJECTIVE: To investigate the degree of language dominance in patients with left and right hemisphere seizure foci compared to normal volunteers using a fMRI reading comprehension task. METHODS: Fifty patients with complex partial epilepsy, aged 8 to 56 years and 33 normal volunteers, aged 7 to 34 had fMRI (1.5 T) and neuropsychological testing. Participants silently named an object described by a sentence compared to a visual control. Data were analyzed with region of interest (ROI) analysis based on t maps for inferior frontal gyrus (IFG), midfrontal gyrus (MFG), and Wernicke area (WA). Regional asymmetry indices (AIs) were calculated [(L - R)/(L + R)]; AI > 0.20 was deemed left dominant and AI < 0.20 as atypical language. RESULTS: Left hemisphere focus patients had a higher likelihood of atypical language than right hemisphere focus patients (21% vs 0%, chi2 < 0.002). Left hemisphere focus patients, excluding those with atypical language, had lower regional AI in IFG, MFG, and WA than controls. Right hemisphere focus patients were all left language dominant and had a lower AI than controls in WA and MFG, but not for IFG. AI in MFG and WA were similar between left hemisphere focus/left language patients and right hemisphere focus patients. Patients activated more voxels than healthy volunteers. Lower AIs were attributable to greater activation in right homologous regions. Less activation in the right-side WA correlated with better verbal memory performance in right focus/left hemisphere-dominant patients, whereas less strongly lateralized activation in IFG correlated better with Verbal IQ in left focus/left hemisphere-dominant patients. CONCLUSIONS: Patients had lower asymmetry indices than healthy controls, reflecting increased recruitment of homologous right hemisphere areas for language processing. Greater right hemisphere activation may reflect greater cognitive effort in patient populations, the effect of epilepsy, or its treatment. Regional activation patterns reflect adaptive efforts at recruiting more widespread language processing networks that are differentially affected based on hemisphere of seizure focus.


Assuntos
Córtex Cerebral/fisiopatologia , Epilepsia/complicações , Lateralidade Funcional/fisiologia , Transtornos da Linguagem/etiologia , Transtornos da Linguagem/fisiopatologia , Rede Nervosa/fisiopatologia , Adaptação Fisiológica/fisiologia , Adolescente , Adulto , Criança , Epilepsia/fisiopatologia , Feminino , Humanos , Idioma , Transtornos da Linguagem/diagnóstico , Testes de Linguagem , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Vias Neurais/fisiopatologia , Plasticidade Neuronal/fisiologia , Valor Preditivo dos Testes , Comportamento Verbal/fisiologia
4.
Neurology ; 63(8): 1403-8, 2004 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-15505156

RESUMO

BACKGROUND: fMRI language tasks reliably identify language areas in presurgical epilepsy patients, but activation using single paradigms may disagree with the intracarotid amobarbital test (IAT). OBJECTIVE: To determine whether a panel of fMRI tasks targeting different aspects of language processing increases accuracy in determining hemisphere language dominance. METHODS: Twenty-six patients age 12 to 56 years, predominantly with temporal lobe epilepsy, were studied using whole-brain 1.5 T fMRI (echo planar imaging, blood oxygenation level-dependent) with three task categories using a block design: verbal fluency, reading comprehension, and auditory comprehension. fMRI t maps were visually rated at three thresholds. All patients had assessment of language lateralization by IAT. RESULTS: fMRI showed left dominance in 21 patients, right dominance in 2, and bilateral activation in 2; raters disagreed over a left vs right bilateral rating in 1 patient. There was full agreement between IAT and fMRI in 21 of 25 patients (IAT failed in 1). In three instances of partial disparity with IAT, the fMRI panel showed consistent findings across raters. Agreement between raters was excellent (partial disagreement in only one patient); the panel of tasks was superior to any single task for interrater agreement (Cramer V 0.93 [range 0.91 to 1.0] vs 0.72 [range 0.60 to 0.86]). CONCLUSIONS: A panel of fMRI language paradigms may be more accurate for evaluating partial epilepsy patients than a single task. A panel of tasks reduces the likelihood of nondiagnostic findings, improves interrater reliability, and helps confirm language laterality.


Assuntos
Córtex Cerebral/fisiologia , Dominância Cerebral/fisiologia , Epilepsia/cirurgia , Testes de Linguagem/normas , Imageamento por Ressonância Magnética/métodos , Cuidados Pré-Operatórios/métodos , Comportamento Verbal/fisiologia , Adolescente , Adulto , Mapeamento Encefálico/instrumentação , Mapeamento Encefálico/métodos , Córtex Cerebral/anatomia & histologia , Circulação Cerebrovascular/fisiologia , Criança , Epilepsia/fisiopatologia , Feminino , Humanos , Idioma , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Percepção da Fala/fisiologia , Lobo Temporal/patologia , Lobo Temporal/fisiopatologia
5.
Neurology ; 60(10): 1598-605, 2003 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-12771248

RESUMO

OBJECTIVE: The organization of neuronal systems that process language in young children is poorly understood. The authors used fMRI to identify brain regions underlying auditory comprehension in healthy young children. METHODS: Fifteen right-handed children (mean age 6.8 years) underwent fMRI at 1.5-T using blood oxygen level dependent echoplanar imaging. They listened to stories with a reverse speech control condition. Group data were analyzed with statistical parametric mapping. Individual subject data were analyzed with a region of interest approach based on t-maps. An asymmetry index (AI = [(L-R)/(L+R)]) was calculated for each region. RESULTS: Group analysis showed significant activation in the left middle temporal gyrus (Brodmann area [BA] 21) and left superior temporal gyrus (BA 22) along the superior temporal sulcus extending back to the angular gyrus (BA 39). Individual maps showed lateralized activation in temporal regions (AI > 0.49 +/- 0.39). There was minimal activation in the frontal lobe. There were no significant correlations between age and regional AI. CONCLUSION: Networks for auditory language processing are regionally localized and lateralized by age 5. These data may provide a means to interpret language fMRI studies performed in preparation for brain surgery, and may be employed to investigate the effect of chronic disease states, such as epilepsy, on language organization during critical periods for plasticity.


Assuntos
Mapeamento Encefálico , Desenvolvimento Infantil , Compreensão , Desenvolvimento da Linguagem , Imageamento por Ressonância Magnética , Rede Nervosa/fisiologia , Vias Auditivas/anatomia & histologia , Vias Auditivas/fisiologia , Criança , Pré-Escolar , Dominância Cerebral , Feminino , Lobo Frontal/fisiologia , Humanos , Masculino , Rede Nervosa/anatomia & histologia , Valores de Referência , Lobo Temporal/fisiologia
6.
Neurology ; 60(1): 94-100, 2003 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-12525725

RESUMO

BACKGROUND: fMRI allows mapping of neural networks underlying cognitive networks during development, but few studies have systematically examined children 7 and younger, in whom language networks may be more diffusely organized than in adults. OBJECTIVE: To identify neural networks during early reading consolidation in young children. METHODS: The authors studied 16 normal, right-handed, native English-speaking children with a mean age of 7.2 years (range 5.8 to 7.9) with fMRI reading paradigms adjusted for reading level. Data were acquired with the echoplanar imaging BOLD technique at 1.5 T. Group data were analyzed with statistical parametric mapping (SPM-99); individual data sets were analyzed with a region of interest approach from individual study t maps (t = 4). The number of activated pixels in brain regions was determined and an asymmetry index (AI) ([L-R]/[L+R]) calculated for each region. RESULTS: In group analysis the authors found prominent activation in left inferior temporal occipital junction and left fusiform gyrus (Brodmann area [BA] 37), middle temporal gyrus (BA 21, 22), middle frontal gyrus (BA 44, 45), and the supplementary motor area. Activation was strongly lateralized in middle frontal gyrus and Wernicke areas (AI 0.54, 0.62). Fourteen subjects had left-sided language lateralization, one was bilateral, and one had poor activation. CONCLUSIONS: The neural networks that process reading are strongly lateralized and regionally specific by age 6 to 7 years. Neural networks in early readers are similar to those in adults.


Assuntos
Mapeamento Encefálico , Rede Nervosa/anatomia & histologia , Rede Nervosa/fisiologia , Leitura , Comportamento Verbal/fisiologia , Criança , Pré-Escolar , Dominância Cerebral/fisiologia , Feminino , Lobo Frontal/anatomia & histologia , Lobo Frontal/fisiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Psicológicos , Lobo Temporal/anatomia & histologia , Lobo Temporal/fisiologia
7.
Neurology ; 59(2): 256-65, 2002 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-12136067

RESUMO

BACKGROUND: fMRI language tasks readily identify frontal language areas; temporal activation has been less consistent. No studies have compared clinical visual judgment to quantitative region of interest (ROI) analysis. OBJECTIVE: To identify temporal language areas in patients with partial epilepsy using a reading paradigm with clinical and ROI interpretation. METHODS: Thirty patients with temporal lobe epilepsy, aged 8 to 56 years, had 1.5-T fMRI. Patients silently named an object described by a sentence compared to a visual control. Data were analyzed with ROI analysis from t-maps. Regional asymmetry indices (AI) were calculated ([L-R]/[L+R]) and language dominance defined as >0.20. t-Maps were visually rated by three readers at three t thresholds. Twenty-one patients had intracarotid amobarbital test (IAT). RESULTS: The fMRI reading task provided evidence of language lateralization in 27 of 30 patients with ROI analysis. Twenty-five were left dominant, two right, one bilateral, and two were nondiagnostic; IAT and fMRI agreed in most patients, three had partial agreement, none overtly disagreed. Interrater agreement ranged between 0.77 to 0.82 (Cramer V; p < 0.0001); agreement between visual and ROI reading with IAT was 0.71 to 0.77 (Cramer V; p < 0.0001). Viewing data at lower thresholds added interpretation to 12 patients on visual analysis and 8 with ROI analysis. CONCLUSIONS: An fMRI reading paradigm can identify language dominance in frontal and temporal areas. Clinical visual interpretation is comparable to quantitative ROI analysis.


Assuntos
Córtex Cerebral/fisiopatologia , Epilepsias Parciais/psicologia , Lateralidade Funcional , Idioma , Imageamento por Ressonância Magnética , Leitura , Adolescente , Adulto , Criança , Epilepsias Parciais/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Desempenho Psicomotor
8.
Clin Orthod Res ; 4(1): 35-42, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11553083

RESUMO

The treatment of skeletal Class III malocclusion is one of the most challenging problems that confronts the practicing orthodontist, particularly in the late deciduous or early mixed dentition periods. In addition to its inherent difficulty, compromised results can also be due to poor patient cooperation; orthopaedic appliances for Class III treatment can be uncomfortable and unaesthetic. There are few acceptable alternatives when a patient refuses to wear an orthopaedic appliance. The aim of this report is to introduce an approach for the treatment of the non compliant dental and skeletal Class III in growing patients. The Smart Wire (SW) is a new orthodontic device simply formed by a 1 mm diameter stainless-steel arch wire that is inserted into the extraoral tube of the upper molar bands. The SW interferes with lower incisors in the front upon mandibular closure. Thus, a distally directed force is applied on the lower incisors and on the mandible while at the same time a mesial force is transmitted onto the upper molars. This combination of force and reaction guides the orthodontic-orthopaedic correction of Class III malocclusions in growing patients.

9.
Neurology ; 57(1): 47-54, 2001 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-11445627

RESUMO

BACKGROUND: fMRI provides a noninvasive means of identifying the location and organization of neural networks that underlie cognitive functions. OBJECTIVE: To identify, using fMRI, brain regions involved in processing written text in children. METHODS: The authors studied nine normal right-handed native English-speaking children, aged 10.2 years (range 7.9 to 13.3 years), with two paradigms: reading Aesop's Fables and "Read Response Naming" (reading a description of an object that was then silently named). Data were acquired using blood oxygen level-dependent fMRI. Group data were analyzed with statistical parametric mapping; individual data sets were analyzed with a region-of-interest approach from individual study t maps. The number of activated pixels was determined in brain regions and an asymmetry index (AI = [L - R]/[L + R]) calculated for each region. RESULTS: The authors found strong activation in the left middle temporal gyrus and left midfrontal gyrus and variable activation in left inferior frontal gyrus for both reading tasks in the group analysis (z > 5.5 to 9.1). All subjects had strong left-sided lateralization for both tasks in middle/superior temporal gyrus, inferior frontal gyrus, and middle frontal gyrus (AI = 0.76 to 1.0 for t = 4). Reading Fables activated twice as many pixels in temporal cortex as the Read Response Naming task; activation in dorsolateral prefrontal cortex was similar for both tasks. Small homologous right middle temporal region activation was seen with reading a fable. CONCLUSIONS: The neural networks that process reading appear to be lateralized and localized by middle to late childhood. Reading text paradigms may prove useful for identifying frontal and temporal language-processing areas and for determining language dominance in children experiencing epilepsy or undergoing tumor surgery.


Assuntos
Mapeamento Encefálico , Córtex Cerebral/fisiologia , Leitura , Circulação Cerebrovascular , Criança , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Oxigênio/sangue , Valores de Referência
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