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1.
Knee Surg Sports Traumatol Arthrosc ; 25(6): 1712-1719, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26499998

RESUMO

PURPOSE: The purpose of our study was to compare the accuracy of the rotational position of the femoral component in total knee arthroplasty aligned with patient individualized jigs (PSJ) to a gap balancing technique (GBT). METHODS: A consecutive series of 21 osteoarthritic patients were treated with 22 cruciate-retaining total knee prostheses. During surgery, the rotation of the femoral component pinholes was recorded for all knees using PSJ and GBT and transferred to computer tomograms (CT). The rotational differences between PSJ and GBT relative to the transepicondylar axis were analysed. RESULTS: The medium rotation of the femoral component pinholes was 1.3° ± 5.1° (min = -6.3°; max = 14.4°) for PSJ and 0.1 ± 1.4° (min = -1.6°; max = 3.4°) for GBT. Outliers of more than 3° were found more frequently with PSJ in 12 cases but only in one for GBT. CONCLUSION: Based on our study, we would not recommend relying intra-operatively solely on the CT-based PSJ without the option to adjust or control femoral rotation. LEVEL OF EVIDENCE: II.


Assuntos
Artroplastia do Joelho , Fêmur/cirurgia , Idoso , Pontos de Referência Anatômicos/cirurgia , Artroplastia do Joelho/métodos , Feminino , Fêmur/diagnóstico por imagem , Fêmur/fisiopatologia , Humanos , Prótese do Joelho , Masculino , Amplitude de Movimento Articular , Rotação , Tomografia Computadorizada por Raios X
2.
J Xray Sci Technol ; 24(3): 379-88, 2016 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-27257876

RESUMO

Grating based X-ray differential phase contrast imaging (DPCI) allows for high contrast imaging of materials with similar absorption characteristics. In the last years' publications, small animals or parts of the human body like breast, hand, joints or blood vessels have been studied. Larger objects could not be investigated due to the restricted field of view limited by the available grating area. In this paper, we report on a new stitching method to increase the grating area significantly: individual gratings are merged on a carrier substrate. Whereas the grating fabrication process is based on the LIGA technology (X-ray lithography and electroplating) different cutting and joining methods have been evaluated. First imaging results using a 2×2 stitched analyzer grating in a Talbot-Lau interferometer have been generated using a conventional polychromatic X-ray source. The image quality and analysis confirm the high potential of the stitching method to increase the field of view considerably.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Interferometria/métodos , Radiografia/métodos , Animais , Anuros , Desenho de Equipamento , Interferometria/instrumentação , Radiografia/instrumentação
3.
Neurologia ; 31(2): 121-9, 2016 Mar.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-24636132

RESUMO

Previous Official Clinical Practice Guidelines (CPGs) in Epilepsy were based on expert opinions and developed by the Epilepsy Study Group of the Spanish Neurological Society (GE-SEN). The current CPG in epilepsy is based on the scientific method, which extracts recommendations from published scientific evidence. A reduction in the variability in clinical practice through standardization of medical practice has become its main function. SCOPE AND OBJECTIVES: This CPG is focused on comprehensive care for individuals affected by epilepsy as a primary and predominant symptom, regardless of the age of onset and medical policy. METHODOLOGY: 1. Creation of GE-SEN neurologists working group, in collaboration with Neuropediatricians, Neurophysiologists and Neuroradiologists. 2. Identification of clinical areas to be covered: diagnosis, prognosis and treatment. 3. Search and selection of the relevant scientific evidence. 4. Formulation of recommendations based on the classification of the available scientific evidence. RESULTS: It contains 161 recommendations of which 57% are consensus between authors and publishers, due to an important lack of awareness in many fields of this pathology. CONCLUSIONS: This Epilepsy CPG formulates recommendations based on explicit scientific evidence as a result of a formal and rigorous methodology, according to the current knowledge in the pre-selected areas. This paper includes the CPG chapter dedicated to emergency situations in seizures and epilepsy, which may present as a first seizure, an unfavorable outcome in a patient with known epilepsy, or status epilepticus as the most severe manifestation.


Assuntos
Epilepsia/terapia , Anticonvulsivantes , Serviços Médicos de Emergência , Medicina Baseada em Evidências , Humanos , Convulsões/terapia
4.
Ann Pharm Fr ; 74(1): 45-8, 2016 Jan.
Artigo em Francês | MEDLINE | ID: mdl-26194063

RESUMO

In early 2012, due to national supply disruption, the methoxy-polyethylene glycol-epoetin beta (CERA) was no longer available and has been replaced by darbepoetin alfa (DA) in all dialysis patients. Official recommendations for the replacement of one by the other is missing or unclear. On this occasion, we wanted to examine how the shift from CERA to DA was done in terms of dose conversion factor and the other factors that could have influenced the dose of DA prescribed (hemoglobin, patient weight, dose of CERA). This retrospective multicenter open conducted in six dialysis centers in Alsace is the first large study (n=263) that evaluated the switch from CERA to DA in all chronic hemodialysis patients. We found that the instantaneous ratio of dose adjustment is close to 1 and that nephrologists are mainly based on the dose of CERA for determining the DA dose, before hemoglobin and weight. However, establishing a true dose-response ratio between the two molecules requires a long term prospective study.


Assuntos
Darbepoetina alfa/uso terapêutico , Eritropoetina/uso terapêutico , Diálise Renal , Idoso , Anemia/tratamento farmacológico , Anemia/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/uso terapêutico , Diálise Renal/efeitos adversos , Estudos Retrospectivos
5.
J Oral Rehabil ; 41(2): 133-40, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24289234

RESUMO

Sensorimotor impairment of the tongue has the potential to affect speech and swallowing. The purpose of this study was to critically examine the effects of nerve preservation and reinnervation after reconstruction of the base of tongue on patient-perceived outcomes of quality of life (QoL) related to speech and swallowing through completion of the EORTC QLQ-H&N35 standardised questionnaire. Thirty participants with a diagnosis of base of tongue cancer underwent primary resection and reconstruction with a radial forearm free flap, which may or may not have included nerve repair to the lingual nerve, hypoglossal nerve or both. Eight QoL domains sensitive to changes in motor and sensory nerve function were included in the analysis. Transected lingual and hypoglossal nerves were associated with difficulty in swallowing, social eating, dry mouth and social contact. There were fewer problems reported when these nerves were either repaired or left intact. There were no significant differences between patient nerve status and QoL outcomes for speech, sticky saliva and use of feeding tubes. This study was the first to examine the impact of sensory or motor nerve transection and reconstruction on health-related QoL outcomes.


Assuntos
Nervo Hipoglosso/cirurgia , Nervo Lingual/cirurgia , Qualidade de Vida , Neoplasias da Língua/cirurgia , Língua/inervação , Deglutição/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos de Cirurgia Plástica/efeitos adversos , Procedimentos de Cirurgia Plástica/métodos , Fala/fisiologia , Retalhos Cirúrgicos , Inquéritos e Questionários , Língua/fisiopatologia , Resultado do Tratamento
6.
Klin Monbl Augenheilkd ; 231(12): 1187-95, 2014 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-25519506

RESUMO

This review documents technical progress in ophthalmic magnetic resonance imaging (MRI) at ultrahigh fields (UHF, B(0) ≥ 7.0 T). The review surveys frontier applications of UHF-MRI tailored for high spatial resolution in vivo imaging of the eye, orbit and optic nerve. Early examples of clinical ophthalmic UHF-MRI including the assessment of melanoma of the choroid membrane and the characterisation of intraocular masses are demonstrated. A concluding section ventures a glance beyond the horizon and explores research promises along with future directions of ophthalmic UHF-MRI.


Assuntos
Neoplasias Oculares/patologia , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Oftalmoscopia/métodos , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Avaliação da Tecnologia Biomédica
7.
Neurologia ; 28(1): 24-32, 2013.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-22608538

RESUMO

INTRODUCTION: There is a major gap in knowledge about the epidemiology of epilepsy in Mediterranean countries. The EPIBERIA group was formed with the aim of promoting the conducting of epidemiological studies in this region in order to improve this situation. This paper deals with the validation of a brief questionnaire for screening patients with epilepsy in the general population. METHODS: We selected an English-language questionnaire previously validated by the Ottman group. It was translated, modified to suit the characteristics of the Spanish population, and administered to a sample of 200 patients (93 epileptics and 107 non-epileptic patient controls) sampled consecutively from 5 epilepsy units in different cities in Spain. Both groups were homogeneous in demographic variables and the control group was representative of the general population. RESULTS: We obtained a sensitivity of 100% and a specificity of 74.77% for the least rigorous correction model for the questionnaire, with a sensitivity of 94.62% and a specificity of 99.07% for the most stringent correction model. The PPV ranged from 7.48% for the first case to 69.49% in the second, assuming an epilepsy prevalence of 2%. CONCLUSIONS: The questionnaire EPIBERIA is a valid Spanish tool for epilepsy screening in the general population in Spain.


Assuntos
Epilepsia/diagnóstico , Epilepsia/epidemiologia , Inquéritos e Questionários , Adulto , Idoso , Anticonvulsivantes/uso terapêutico , Epilepsia/terapia , Feminino , Humanos , Idioma , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Convulsões/fisiopatologia , Espanha
8.
Sci Rep ; 13(1): 4673, 2023 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-36949092

RESUMO

The current COVID19 pandemic is caused by a positive-sense single-stranded RNA virus, which presents high mutational rates. The development of effective therapeutics and mitigation strategies using vaccination or therapeutic antibodies faces serious challenges because of the regular emergence of immune escape variants of the virus. An efficient approach would involve the use of an agent to non-specifically limit or block viruses contacting the mucosae and therefore entering the body. Here, we investigated the ability of a micronized purified clinoptilolite-tuff to bind and neutralize different viruses from the Coronaviridae family. Using plaque assay, RT-qPCR and immunostaining, the adsorption and inactivation of the seasonal human coronavirus HCoV-229E and of 2 SARS-CoV-2 variants were demonstrated. The resulting data suggest that purified clinoptilolite-tuff could be used as an ingredient in new medical devices and/or pharmaceuticals to prevent or mitigate SARS-CoV-2 dissemination.


Assuntos
COVID-19 , Coronaviridae , Humanos , SARS-CoV-2
9.
Neuroimage ; 59(4): 3316-24, 2012 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-22155040

RESUMO

It is crucial to understand what brain signals can be decoded from single trials with different recording techniques for the development of Brain-Machine Interfaces. A specific challenge for non-invasive recording methods are activations confined to small spatial areas on the cortex such as the finger representation of one hand. Here we study the information content of single trial brain activity in non-invasive MEG and EEG recordings elicited by finger movements of one hand. We investigate the feasibility of decoding which of four fingers of one hand performed a slight button press. With MEG we demonstrate reliable discrimination of single button presses performed with the thumb, the index, the middle or the little finger (average over all subjects and fingers 57%, best subject 70%, empirical guessing level: 25.1%). EEG decoding performance was less robust (average over all subjects and fingers 43%, best subject 54%, empirical guessing level 25.1%). Spatiotemporal patterns of amplitude variations in the time series provided best information for discriminating finger movements. Non-phase-locked changes of mu and beta oscillations were less predictive. Movement related high gamma oscillations were observed in average induced oscillation amplitudes in the MEG but did not provide sufficient information about the finger's identity in single trials. Importantly, pre-movement neuronal activity provided information about the preparation of the movement of a specific finger. Our study demonstrates the potential of non-invasive MEG to provide informative features for individual finger control in a Brain-Machine Interface neuroprosthesis.


Assuntos
Eletroencefalografia , Dedos/fisiologia , Magnetoencefalografia , Córtex Motor/fisiologia , Movimento/fisiologia , Adulto , Feminino , Mãos/fisiologia , Humanos , Masculino , Adulto Jovem
10.
J Oral Rehabil ; 39(3): 170-81, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21923892

RESUMO

Primary treatment of oropharyngeal cancer often involves surgical resection and reconstruction of the affected area. However, during base of tongue reconstruction the lingual nerve is often severed on one or both sides, affecting sensation in the preserved tissue of the anterior tongue. The loss of specific tongue sensations could negatively affect a person's oral function and quality of life. The aim of this study was to explore the effects of different types of lingual nerve intervention on sensory function for patients with base of tongue cancer as compared to healthy, age-matched adults. Subjects included 30 patients who had undergone primary oropharyngeal reconstruction with a radial forearm free-flap and 30 matched controls. Sensations tested were temperature, two-point discrimination, light touch, taste, oral stereognosis and texture on the anterior two-thirds of the tongue. Results indicated that type of surgical nerve repair may not have a significant impact on overall sensory outcomes, providing mixed results for either nerve repair technique. Sensations for the nonoperated tongue side and operated side with lingual nerve intact were comparable to matched controls, with mixed outcomes for nerve repair. The poorest sensory outcomes were observed in patients with the lingual nerve severed, while all patients with lingual nerve intervention exhibited deteriorated taste sensation on the affected tongue side. Overall, patients in this study who had undergone oropharyngeal reconstruction with lingual nerve intervention exhibited decreased levels of sensation on the operated tongue side, with minimal differences between types of lingual nerve repair.


Assuntos
Traumatismos do Nervo Lingual/cirurgia , Nervo Lingual/cirurgia , Procedimentos Neurocirúrgicos/efeitos adversos , Sensação/fisiologia , Neoplasias da Língua/cirurgia , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Antebraço/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/métodos , Retalhos Cirúrgicos , Resultado do Tratamento
11.
Neurologia ; 27(9): 575-84, 2012.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-22078651

RESUMO

INTRODUCTION: Drug-resistant epilepsy (DRE) is a top-priority social health problem which requires early individual treatment due to its dramatic repercussions for the patient and society. DEVELOPMENT: The International League Against Epilepsy (ILAE) has recently defined DRE as that in which the seizures are not controlled after having correctly taken two appropriate and well tolerated anti-epileptic drugs, with lack of control being understood as the appearance of seizures within one year or in a period less than three times the inter-seizure interval before starting treatment. This International Society recommends a rapid and detailed assessment of all patients in an Epilepsy Unit. A Clinical Epilepsy Unit (CEU) is understood as a group of professionals who, acting in collaboration, have the diagnosis and treatment of the patient with epilepsy as their primary objective. CEUs in Spain may be stratified into different levels depending on the activity carried out in each of them. The specific epilepsy clinic is considered the fundamental type of CEU and includes the necessary figure of an expert in epilepsy. Prolonged video-monitoring is performed in medical CEUs. In medical-surgical CEUs epilepsy surgery with varying degrees of difficulty is also performed. CONCLUSIONS: All CEUs must cooperate with consensus protocols, and there must be a two-way flow between them. Stratification of CEUs increases efficacy and efficiency, due to there being a sufficient number of them to ensure easy access by all patients with epilepsy.


Assuntos
Epilepsia/diagnóstico , Epilepsia/terapia , Anticonvulsivantes/efeitos adversos , Anticonvulsivantes/uso terapêutico , Resistência a Medicamentos , Necessidades e Demandas de Serviços de Saúde , Unidades Hospitalares , Humanos , Espanha , Terminologia como Assunto
12.
Neurologia ; 27(8): 481-90, 2012 Oct.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-22078652

RESUMO

OBJECTIVE: To ascertain the opinions of an Epilepsy Expert Group and prepare a consensus document on the definition of drug-resistant epilepsy (DRE) according to the International League Against Epilepsy (ILAE) and the different healthcare levels for the patient with epilepsy in Spain. MATERIAL AND METHODS: The study was conducted using the Delphi method, by means of successive rounds of questionnaires. A scientific committee prepared a preliminary document and fourteen associated questions, which were sent by e-mail to the panel of experts. They included items related to the concept of DRE, health care levels and the route between these levels for patients with DRE. RESULTS: A total of 41 experts answered the questionnaire. They agreed regarding the necessity and applicability of the DRE definition according to the ILAE, the need for an expert panel on epilepsy, specialist epilepsy clinics, and clinical epilepsy units stratified depending on the level of activities they carried out. There was moderate consensus on the resources and activity of the clinical units of reference and there was no consensus on the referral of patients who have suffered an epileptic seizure to an epilepsy clinic. CONCLUSIONS: The expert panel agreed with the definition of DRE according to the ILAE and on referring patients with DRE for a detailed study in an epilepsy clinic or epilepsy clinical unit. They highlighted the need for video-EEG monitoring in the study of patients with DRE and the need to propose other forms of treatment in selected patients.


Assuntos
Epilepsia/diagnóstico , Epilepsia/terapia , Protocolos Clínicos , Consenso , Técnica Delphi , Resistência a Medicamentos , Eletroencefalografia , Epilepsia/tratamento farmacológico , Pesquisas sobre Atenção à Saúde , Humanos , Espanha
13.
Oncology ; 80(5-6): 330-2, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21791942

RESUMO

After failure of temozolomide, there is no established standard salvage chemotherapy for patients with recurrent glioblastoma (GBM). Two phase II trials combining ifosfamide, carboplatin and etoposide chemotherapy (ICE) showed favorable results. We therefore applied the ICE protocol to 13 patients (10 GBM, 3 anaplastic astrocytomas). Partial or complete remissions were not observed. None of the 13 patients survived progression-free for 6 months. Our retrospective analysis suggests that the ICE regimen is not effective in patients with recurrent high-grade glioma if applied at second or third relapse.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Astrocitoma/tratamento farmacológico , Neoplasias Encefálicas/tratamento farmacológico , Glioma/tratamento farmacológico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Astrocitoma/secundário , Neoplasias Encefálicas/patologia , Carboplatina/administração & dosagem , Dacarbazina/análogos & derivados , Dacarbazina/uso terapêutico , Esquema de Medicação , Etoposídeo/administração & dosagem , Feminino , Glioma/secundário , Humanos , Ifosfamida/administração & dosagem , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Temozolomida , Falha de Tratamento
14.
Poult Sci ; 98(5): 2080-2086, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30566631

RESUMO

The current study evaluated the effects of different inclusion levels of microbial muramidase (Muramidase 007, DSM Nutritional Products) on gastrointestinal functionality by determination of apparent ileal digestibility (AID) of nutrients, investigation of intestinal histomorphology, and quantification of resulting growth performance. Four maize-wheat-soybean experimental diets were produced without (C) and with different dosages of muramidase: low (L, 25,000 LSU(F)/kg), medium (M, 35,000 LSU(F)/kg), and high (H, 45,000 LSU(F)/kg); diets were fed to broilers for 35 d. At the end of the experiment, AID of ether extract (EE), crude protein (CP), Ca, and P were determined and samples of the mid-jejunum and -ileum were collected for histomorphological observations. Data were subjected to ANOVA analysis using the GLM procedure. Orthogonal polynomial contrasts were used to assess linear and quadratic effects of different levels of the muramidase. At the end of the trial, Muramidase 007 supplementation linearly increased body weight gain and decreased feed conversion ratio (FCR) (P ≤ 0.05). Adding the muramidase to broiler diets also linearly increased the European poultry efficiency factor (P ≤ 0.05). Inclusion of the muramidase in broiler diets linearly increased AID of CP, EE, and P (P ≤ 0.05), and the H group had a higher AID of EE and CP compared to C group (P ≤ 0.05). Microbial muramidase supplementation linearly increased ileal villus length to crypt depth ratio and decreased the number of ileal CD45 cells (P ≤ 0.05). Broilers fed M and H diets had fewer number of CD45 cells in the ileum compared to those in C group (P ≤ 0.05). In conclusion, the results of the present study demonstrated that inclusion of the microbial muramidase in broiler diets could increase AID of key nutrients and improve growth performance in broilers. Adding microbial muramidase to broiler diets can therefore be considered as an interesting prospect to improve gastrointestinal functionality. Biological mechanisms causing these improvements need to be studied further.


Assuntos
Galinhas/fisiologia , Digestão , Íleo/enzimologia , Intestinos/efeitos dos fármacos , Muramidase/metabolismo , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Animais , Galinhas/anatomia & histologia , Galinhas/crescimento & desenvolvimento , Dieta/veterinária , Suplementos Nutricionais/análise , Digestão/efeitos dos fármacos , Relação Dose-Resposta a Droga , Metabolismo Energético , Íleo/fisiologia , Intestinos/anatomia & histologia , Masculino , Muramidase/administração & dosagem , Nutrientes/metabolismo , Distribuição Aleatória
15.
Cell Death Differ ; 13(7): 1156-69, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16254573

RESUMO

Conditionally BCL-xL-overexpressing LNT-229 Tet-On glioma cell clones were generated to investigate whether the 'antiapoptosis phenotype' and the 'motility phenotype' mediated by BCL-2 family proteins in glioma cells could be separated. BCL-xL induction led to an immediate and concentration-dependent protection of LNT-229 cells from apoptosis. BCL-xL induction for up to 3 days did not result in altered invasiveness. In contrast, long-term BCL-xL induction for 21 days resulted in increased transforming growth factor-beta2 expression, and in metalloproteinase-2 and -14 dependent, but integrin independent, increased invasiveness. Withdrawal of doxycycline (Dox) abolished the protection from apoptosis whereas the 'invasion phenotype' remained stable. Dox stimulation of BCL-xL-inducible LNT-229 cells conferred infiltrative growth to BCL-xL-positive glioma cells in vivo and reduced the survival of tumor-bearing mice. These data allow to dissect a direct antiapoptotic action of BCL-xL from an indirect effect, presumably mediated by altered gene expression, which modifies tumor cell invasiveness in vitro and in vivo.


Assuntos
Apoptose/fisiologia , Movimento Celular/fisiologia , Glioma/patologia , Proteína bcl-X/fisiologia , Animais , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/terapia , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Doxiciclina/farmacologia , Glioma/genética , Glioma/terapia , Humanos , Immunoblotting , Metaloproteinase 2 da Matriz/metabolismo , Camundongos , Camundongos Nus , Células NIH 3T3 , Invasividade Neoplásica , Análise de Sobrevida , Fatores de Tempo , Transfecção , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta2 , Ensaios Antitumorais Modelo de Xenoenxerto , Proteína bcl-X/genética
16.
Curr Biol ; 10(13): 805-8, 2000 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-10898985

RESUMO

Although color plays a prominent part in our subjective experience of the visual world, the evolutionary advantage of color vision is still unclear [1] [2], with most current answers pointing towards specialized uses, for example to detect ripe fruit amongst foliage [3] [4] [5] [6]. We investigated whether color has a more general role in visual recognition by looking at the contribution of color to the encoding and retrieval processes involved in pattern recognition [7] [8] [9]. Recognition accuracy was higher for color images of natural scenes than for luminance-matched black and white images, and color information contributed to both components of the recognition process. Initially, color leads to an image-coding advantage at the very early stages of sensory processing, most probably by easing the image-segmentation task. Later, color leads to an advantage in retrieval, presumably as the result of an enhanced image representation in memory due to the additional attribute. Our results ascribe color vision a general role in the processing of visual form, starting at the very earliest stages of analysis: color helps us to recognize things faster and to remember them better.


Assuntos
Cognição/fisiologia , Percepção de Cores/fisiologia , Natureza , Percepção/fisiologia , Testes de Percepção de Cores , Sensibilidades de Contraste , Humanos , Medições Luminescentes , Memória/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Fatores de Tempo , Vias Visuais/fisiologia
17.
Eur J Med Res ; 12(2): 84-9, 2007 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-17369122

RESUMO

OBJECTIVE: Staging of bronchial carcinoma presents a diagnostic challenge. In addition to CT scans, endobronchial ultrasound is used. The aim of this study was to compare the diagnostic accuracy of high-resolution multidetector CT (MSCT) with that of endobronchial ultrasound with respect of detection and extension of the bronchial lesions. METHODS: 24 patients with lesions in the central bronchial area were examined using both EBUS and MSCT. Multiplanar reconstructions (MPR) as well as virtual endoscopy (VE) were used as adjuncts in this investigation of the comparative diagnostic accuracy of MSCT and EBUS in the imaging of bronchial lesions. RESULTS: No significant difference could be established between EBUS and MSCT in detecting and extension of bronchial lesions. With both procedures, the use of supplementary techniques may be advantageous and helpful in individual cases. CONCLUSIONS: When compared with EBUS, MSCT with post-processing has equally high sensitivity with regard to the visualization of malign endobronchial lesions.


Assuntos
Brônquios/patologia , Carcinoma Broncogênico/diagnóstico , Endossonografia/métodos , Tomografia Computadorizada por Raios X/métodos , Brônquios/diagnóstico por imagem , Carcinoma Broncogênico/diagnóstico por imagem , Constrição Patológica/diagnóstico , Humanos , Estadiamento de Neoplasias/métodos , Sensibilidade e Especificidade
18.
J Colloid Interface Sci ; 315(1): 107-15, 2007 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-17720181

RESUMO

Adsorption on ZnO of sodium poly(acrylate) (PAA), sodium poly(styrene sulfonate) (PSS) and a monomer surfactant [hydroxyethylidene diphosphonate (HEDP)] was investigated in suspensions initially equilibrated at pH 7. Results demonstrate interplay in the adsorption mechanism between zinc complexation, salt precipitation, and ZnO dissolution. In the case of PAA, the adsorption isotherm exhibits a maximum attributed to the precipitation of zinc polyacrylate. PSS and HEDP formed high-affinity adsorption isotherms, but the plateau adsorption of HEDP was significantly lower than that of PSS. The adsorption isotherm of each additive is divided into two areas. At low additive concentration (high zinc/additive ratio), the total zinc concentration in the solution decreased and the pH increased upon addition. At a higher additive ratio, zinc concentration and pH increased with the organic concentration. The increase in pH is due to the displacement of hydroxyl ions from the surface and the increase in zinc concentration results from the dissolution of ZnO due to the complexation of zinc ions by the organics. The stability of the ZnO dispersions was investigated by measurement of the particle size distribution after addition of various amounts of polymers. The three additives stabilized the ZnO dispersions efficiently once full surface coverage was reached.

19.
Phys Med Biol ; 62(16): 6729-6745, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28762340

RESUMO

We report on a radiographic measurement of an ex vivo human knee using a grating-based phase-contrast imaging setup and a medical x-ray tube at a tube voltage of 70 kV. The measurement has been carried out using a Talbot-Lau setup that is suitable to achieve a high visibility in the energy regime of medical imaging. In a medical reading by an experienced trauma surgeon signatures of chondrocalcinosis in the medial meniscus have been identified more evidently using the dark-field image in comparison to the conventional attenuation image. The analysis has been carried out at various dose levels down to 0.14 mGy measured as air kerma, which is a dose comparable to clinically used radiographic devices. The diagnosis has been confirmed by a histological analysis of the meniscus tissue. In the introduced high-frequency filtered phase-contrast image the anterior and posterior horn of the medial meniscus and the posterior cruciate ligament have also been visible. Furthermore, atherosclerotic plaque is visible in both imaging modalities, attenuation and dark-field, despite the presence of overlaying bone. This measurement, for the first time, proves the feasibility of Talbot-Lau x-ray imaging at high-energy spectra above 40 kVp and reasonable dose levels with regard to spacious and dense objects.


Assuntos
Joelho/diagnóstico por imagem , Radiografia/métodos , Estudos de Viabilidade , Humanos , Doses de Radiação
20.
Neuroscience ; 141(4): 2029-39, 2006 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-16777350

RESUMO

Activation of the adenosine A(2A) receptor (A(2A)R) at the time of reperfusion has been shown to reduce ischemia-reperfusion injury in peripheral tissues and spinal cord. In this study we show that treating mice with the A(2A)R agonist, 4-{3-[6-amino-9-(5-cyclopropylcarbamoyl-3,4-dihydroxy-tetrahydro-furan-2-yl)-9H-purin-2-yl]-prop-2-ynyl}-piperidine-1-carboxylic acid methyl ester for four days beginning before or just after the onset of reperfusion after compression-induced spinal cord injury rapidly (within 1 day) and persistently (>42 days) reduces locomotor dysfunction and spinal cord demyelination. Protection is abolished in knockout/wild type bone marrow chimera mice selectively lacking the A(2A)R only on bone marrow-derived cells but retaining receptors on other tissues including blood vessels. Paradoxically, reduced spinal cord injury is also noted in A(2A)R -/- mice, and in wild type/knockout bone marrow chimera mice selectively lacking the A(2A)R on non-bone marrow-derived cells, or in mice treated with the A(2A) antagonist, 4-(2-[7-amino-2-[2-furyl][1,2,4]triazolo[2,3-a][1,3,5]triazin-5-yl-amino]ethyl)phenol. The greatest protection is seen in knockout/wild type bone marrow chimera mice treated with 4-{3-[6-amino-9-(5-cyclopropylcarbamoyl-3,4-dihydroxy-tetrahydro-furan-2-yl)-9H-purin-2-yl]-prop-2-ynyl}-piperidine-1-carboxylic acid methyl ester, i.e. by activating the A(2A)R in mice expressing the receptor only in bone marrow-derived cells. The data suggest that inflammatory bone marrow-derived cells are the primary targets of A(2A) agonist-mediated protection. We conclude that A(2A) agonists or other interventions that inhibit inflammation during and after spinal cord ischemia may be effective in reducing spinal cord injury in patients, but excessive or prolonged stimulation of the A(2A)R may be counterproductive. It may be possible to devise strategies to produce optimal spinal cord protection by exploiting temporal differences in A(2A)R-mediated responses.


Assuntos
Células da Medula Óssea/metabolismo , Transplante de Medula Óssea/métodos , Receptor A2A de Adenosina/genética , Receptor A2A de Adenosina/metabolismo , Compressão da Medula Espinal/metabolismo , Compressão da Medula Espinal/terapia , Agonistas do Receptor A2 de Adenosina , Análise de Variância , Animais , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , Feminino , Camundongos , Camundongos Knockout , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Bainha de Mielina/patologia , Piperidinas/química , Piperidinas/farmacologia , Ensaio Radioligante/métodos , Compressão da Medula Espinal/patologia , Compressão da Medula Espinal/fisiopatologia , Fatores de Tempo , Triazinas/farmacocinética , Triazóis/farmacocinética
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