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1.
Ann Pathol ; 39(2): 167-171, 2019 Apr.
Artigo em Francês | MEDLINE | ID: mdl-30554833

RESUMO

Clear cells sarcomas (CCS) are exceptionally rare in the tongue, with, to our knowledge, only three previous reports in anglo-saxon literature. Through our case, we will discuss the differential diagnosis of clear cells tumors of the tongue and bring this tumour closer to the newly described entity of the gastrointestinal tract named "clear cells sarcoma-like gastrointestinal (SCCLGI)", recently renamed "gastrointestinal neuroectodermal tumour (GNET)". SCCLGI/GNET share morphological and molecular characteristics with SCC but had until then been observed only in the digestive tract. Our case could be a lingual localization of a SCCLGI/GNET. SCC and SCCLGI/GNET characteristic molecular profil involves EWSR1-ATF1 [t(12; 22) (q13; q12)] and EWSR1-CREB1 [t(2; 22) (q34; q12)] fusion genes, but it is not specific of these tumours.


Assuntos
Tumores Neuroectodérmicos/patologia , Sarcoma de Células Claras/patologia , Neoplasias da Língua/patologia , Adulto , Diagnóstico Diferencial , Feminino , Neoplasias Gastrointestinais/patologia , Humanos
2.
J Neurosci ; 36(41): 10673-10682, 2016 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-27733617

RESUMO

Spontaneous ventilation in mammals is driven by automatic brainstem networks that generate the respiratory rhythm and increase ventilation in the presence of increased carbon dioxide production. Hypocapnia decreases the drive to breathe and induces apnea. In humans, this occurs during sleep but not during wakefulness. We hypothesized that hypocapnic breathing would be associated with respiratory-related cortical activity similar to that observed during volitional breathing, inspiratory constraints, or in patients with defective automatic breathing (preinspiratory potentials). Nineteen healthy subjects were studied under passive (mechanical ventilation, n = 10) or active (voluntary hyperventilation, n = 9) profound hypocapnia. Ventilatory and electroencephalographic recordings were performed during voluntary sniff maneuvers, normocapnic breathing, hypocapnia, and after return to normocapnia. EEG recordings were analyzed with respect to the ventilatory flow signal to detect preinspiratory potentials in frontocentral electrodes and to construct time-frequency maps. After passive hyperventilation, hypocapnia was associated with apnea in 3 cases and ventilation persisted in 7 cases (3 and 6 after active hyperventilation, respectively). No respiratory-related EEG activity was observed in subjects with hypocapnia-related apneas. In contrast, preinspiratory potentials were present at vertex recording sites in 12 of the remaining 13 subjects (p < 0.001). This was corroborated by time-frequency maps. This study provides direct evidence of a cortical substrate to hypocapnic breathing in awake humans and fuels the notion of corticosubcortical cooperation to preserve human ventilation in a variety of situations. Of note, maintaining ventilatory activity at low carbon dioxide levels is among the prerequisites to speech production insofar as speech often induces hypocapnia. SIGNIFICANCE STATEMENT: Human ventilatory activity persists, during wakefulness, even when hypocapnia makes it unnecessary. This peculiarity of human breathing control is important to speech and speech-breathing insofar as speech induces hypocapnia. This study evidences a specific respiratory-related cortical activity. This suggests that human hypocapnic breathing is driven, at least in part, by cortical mechanisms similar to those involved in volitional breathing, in breathing against mechanical constraints or with weak inspiratory muscle, and in patients with defective medullary breathing pattern generators. This fuels the notion that the human ventilatory drive during wakefulness often results from a corticosubcortical cooperation, and opens new avenues to study certain ventilatory and speech disorders.


Assuntos
Córtex Cerebral/fisiopatologia , Impulso (Psicologia) , Hipocapnia/fisiopatologia , Respiração , Vigília , Mapeamento Encefálico , Dióxido de Carbono/metabolismo , Eletroencefalografia , Feminino , Humanos , Masculino , Respiração Artificial , Sono , Adulto Jovem
3.
Clin Nucl Med ; 43(4): e118-e121, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29401145

RESUMO

F-FDG PET/CT and MRI were performed in a 44-year-old woman to characterize a mass of the anterior tongue. MR images showed a voluminous mass, well circumscribed and enhanced heterogeneously after gadolinium chelates injection. There was an intense uptake on PET/CT. Pathological examination and molecular analysis revealed the diagnosis of clear cell sarcoma of the tongue. We present a case of clear cell sarcoma of the tongue, which includes imaging features. It is an extremely rare tumor, with only 3 cases previously reported in the literature.


Assuntos
Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Sarcoma de Células Claras/diagnóstico por imagem , Neoplasias da Língua/diagnóstico por imagem , Adulto , Feminino , Fluordesoxiglucose F18 , Humanos
4.
Cogn Neuropsychol ; 24(6): 623-60, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18416512

RESUMO

We investigated the visual word recognition ability of M.T., a young boy with surface dyslexia, by means of a paradigm that measures performance as a function of the eye fixation position within the word, known as the "viewing-position effect" paradigm. In well-achieving readers, the viewing-position effect is mainly determined by factors affecting letter visibility and by lexical constraints on word recognition. We further quantified M.T.'s sensory limitations on letter visibility by computing visual-span profiles - that is, the number of letters recognizable at a glance. Finally, in an ideal-observer's perspective, M.T.'s performance was compared with a parameter-free model combining M.T.'s letter visibility data with a simple lexical matching rule. The results showed that M.T. did not use the whole visual information available on letter identities to recognize words and that preorthographical factors constrained his word recognition performance. The results can be best accounted for by a reduction of the number of letters processed in parallel.


Assuntos
Dislexia/diagnóstico , Reconhecimento Psicológico , Percepção Visual , Vocabulário , Adolescente , Conscientização , Humanos , Masculino , Memória de Curto Prazo , Fonética , Índice de Gravidade de Doença
5.
Vision Res ; 47(19): 2521-30, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17719073

RESUMO

The eye movements of 14 French dyslexic children having a VA span reduction and 14 normal readers were compared in two tasks of visual search and text reading. The dyslexic participants made a higher number of rightward fixations in reading only. They simultaneously processed the same low number of letters in both tasks whereas normal readers processed far more letters in reading. Importantly, the children's VA span abilities related to the number of letters simultaneously processed in reading. The atypical eye movements of some dyslexic readers in reading thus appear to reflect difficulties to increase their VA span according to the task request.


Assuntos
Atenção , Dislexia/fisiopatologia , Leitura , Movimentos Sacádicos , Criança , Dislexia/psicologia , Medições dos Movimentos Oculares , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Estimulação Luminosa/métodos , Desempenho Psicomotor
6.
Medicine (Baltimore) ; 94(20): e523, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25997035

RESUMO

Anticitrullinated peptide/protein antibodies (ACPA), which are highly specific for rheumatoid arthritis (RA), may be found in some patients with other systemic autoimmune diseases. The clinical significance of ACPA in patients with antisynthetase syndrome (ASS), a systemic disease characterized by the association of myositis, interstitial lung disease, polyarthralgia, and/or polyarthritis, has not yet been evaluated with regard to phenotype, prognosis, and response to treatment. ACPA-positive ASS patients were first identified among a French multicenter registry of patients with ASS. Additionally, all French rheumatology and internal medicine practitioners registered on the Club Rhumatismes et Inflammation web site were asked to report their observations of ASS patients with ACPA. The 17 collected patients were retrospectively studied using a standardized questionnaire and compared with 34 unselected ACPA-negative ASS patients in a case-control study. All ACPA-positive ASS patients suffered from arthritis versus 41% in the control group (P < 0.0001). The number of swollen joints was significantly higher (7.0 ±â€Š5.0 vs 2.9 ±â€Š3.9, P < 0.005), with a distribution resembling that of RA. Radiographic damages were also more frequent in ACPA-positive ASS patients (87% vs 11%, P < 0.0001). Aside from a significantly higher transfer factor for carbon monoxide in ACPA-ASS patients, lung, muscle, and skin involvements had similar incidences, patterns, and severity in both groups. Although Nonbiologic treatments were similarly used in both groups, ACPA-positive patients received biologics more frequently (59% vs 12%, P < 0.0008), mostly due to refractory arthritis (n = 9). Eight patients received anti-Cluster of differentiation 20 (CD20) monoclonal antibodies (mAbs) with good efficacy and tolerance, whereas 2 of the 5 patients treated with antitumor necrosis factor drugs had worsened myositis and/or interstitial lung disease. After a >7-year mean follow-up, extra-articular outcomes and survival were not different. ACPA-positive ASS patients showed an overlapping RA-ASS syndrome, were at high risk of refractory erosive arthritis, and might experience ASS flare when treated with antitumor necrosis factor drugs. In contrast, other biologics such as anti-CD20 mAb were effective in this context, without worsening systemic involvements.


Assuntos
Artrite Reumatoide/sangue , Autoanticorpos/sangue , Miosite/sangue , Adulto , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/diagnóstico por imagem , Artrite Reumatoide/patologia , Estudos de Casos e Controles , Feminino , Humanos , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/patologia , Miosite/diagnóstico , Miosite/diagnóstico por imagem , Miosite/patologia , Radiografia , Estudos Retrospectivos , Índice de Gravidade de Doença , Pele/patologia , Inquéritos e Questionários
7.
PLoS One ; 8(5): e64803, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23734220

RESUMO

To understand why human sensitivity for complex objects is so low, we study how word identification combines eye and ear or parts of a word (features, letters, syllables). Our observers identify printed and spoken words presented concurrently or separately. When researchers measure threshold (energy of the faintest visible or audible signal) they may report either sensitivity (one over the human threshold) or efficiency (ratio of the best possible threshold to the human threshold). When the best possible algorithm identifies an object (like a word) in noise, its threshold is independent of how many parts the object has. But, with human observers, efficiency depends on the task. In some tasks, human observers combine parts efficiently, needing hardly more energy to identify an object with more parts. In other tasks, they combine inefficiently, needing energy nearly proportional to the number of parts, over a 60∶1 range. Whether presented to eye or ear, efficiency for detecting a short sinusoid (tone or grating) with few features is a substantial 20%, while efficiency for identifying a word with many features is merely 1%. Why? We show that the low human sensitivity for words is a cost of combining their many parts. We report a dichotomy between inefficient combining of adjacent features and efficient combining across senses. Joining our results with a survey of the cue-combination literature reveals that cues combine efficiently only if they are perceived as aspects of the same object. Observers give different names to adjacent letters in a word, and combine them inefficiently. Observers give the same name to a word's image and sound, and combine them efficiently. The brain's machinery optimally combines only cues that are perceived as originating from the same object. Presumably such cues each find their own way through the brain to arrive at the same object representation.


Assuntos
Orelha/fisiologia , Audição/fisiologia , Fenômenos Fisiológicos Oculares , Reconhecimento Visual de Modelos/fisiologia , Estimulação Acústica , Adolescente , Adulto , Algoritmos , Limiar Auditivo/fisiologia , Sinais (Psicologia) , Humanos , Idioma , Pessoa de Meia-Idade , Modelos Biológicos , Estimulação Luminosa , Desempenho Psicomotor/fisiologia , Limiar Sensorial/fisiologia , Percepção Visual/fisiologia , Testes de Associação de Palavras , Adulto Jovem
8.
PLoS One ; 8(4): e58097, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23593117

RESUMO

A steady increase in reading speed is the hallmark of normal reading acquisition. However, little is known of the influence of visual attention capacity on children's reading speed. The number of distinct visual elements that can be simultaneously processed at a glance (dubbed the visual attention span), predicts single-word reading speed in both normal reading and dyslexic children. However, the exact processes that account for the relationship between the visual attention span and reading speed remain to be specified. We used the Theory of Visual Attention to estimate visual processing speed and visual short-term memory capacity from a multiple letter report task in eight and nine year old children. The visual attention span and text reading speed were also assessed. Results showed that visual processing speed and visual short term memory capacity predicted the visual attention span. Furthermore, visual processing speed predicted reading speed, but visual short term memory capacity did not. Finally, the visual attention span mediated the effect of visual processing speed on reading speed. These results suggest that visual attention capacity could constrain reading speed in elementary school children.


Assuntos
Atenção , Leitura , Visão Ocular , Criança , Pré-Escolar , Humanos , Modelos Biológicos , Fatores de Tempo
9.
Cortex ; 46(6): 717-38, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20116054

RESUMO

While there is growing evidence that some dyslexic children suffer from a deficit in simultaneously processing multiple visually displayed elements, the precise nature of the deficit remains largely unclear. The aim of the present study is to investigate possible cognitive impairments at the source of this deficit in dyslexic children. The visual processing of simultaneously presented letters was thus thoroughly assessed in two dyslexic children by means of a task that requires the report of briefly presented multi-letters arrays. A computational model of the attentional involvement in multi-object recognition (Bundesen, 1990, 1998) served as framework for analysing the data. By combining psychophysical measurements with computational modelling, we demonstrated that the visual processing deficit of simultaneously displayed letters, observed in the two dyslexic individuals reported in the current study, stems from at least two distinct cognitive sources: a reduction of the rate of-letter-information uptake, and a limitation of the maximal number of elements extracted from a brief visual display and stored in visual short-term memory. Possible relations between these impairments and learning to read proficiently are discussed.


Assuntos
Transtornos Cognitivos/fisiopatologia , Dislexia/fisiopatologia , Reconhecimento Psicológico/fisiologia , Percepção Visual/fisiologia , Atenção/fisiologia , Criança , Simulação por Computador , Feminino , Humanos , Testes de Linguagem , Masculino , Memória de Curto Prazo/fisiologia , Modelos Neurológicos , Testes Neuropsicológicos , Estimulação Luminosa , Psicofísica
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