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1.
Clin Radiol ; 74(1): 79.e1-79.e9, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30336942

RESUMO

AIM: To investigate the effect of colour scale choice on diagnostic performance in the interpretation of medical images. MATERIALS AND METHODS: Twelve clinicians interpreted 210 myocardial computed tomography (CT) perfusion (CTP) examinations, and nine clinicians interpreted 165 magnetic resonance imaging (MRI) apparent diffusion coefficient (ADC) prostate images. In three separate sessions, each participant read the same image set using greyscale, hot-iron, and rainbow scales, respectively. Participants scored their level of confidence for tumour presence in the ADC study, and for ischaemia in the CTP study, from 0 to 100. The area under the receiver operating characteristic (ROC) curve (AUC) was used as the performance metric. For cases that scored >50, CTP readers' agreement on the ischaemic transmural extent was analysed, and ADC map readers' selected values and coordinates for the lowest ADC within the detected tumour were compared across different colour scales. RESULTS: For CTP detection, the AUC was up to 0.10 higher with greyscale, 0.67±0.02 (standard error), compared to rainbow, 0.56±0.02, and detection with hot-iron was in between (0.61±0.03). For ischaemic transmural lesion categorisation, observed inter-reader agreement was highest with greyscale for category 25-50%. There is a small tendency for rainbow and greyscale to outperform hot-iron in the detection of prostate tumours. The selected lowest ADC value and pixel localisation was similar with all colour scales. CONCLUSIONS: The present findings suggest that colour visualisation has a measurable effect on CTP and ADC performance. Further investigation is necessary to determine the magnitude of the effect in diagnostic tasks.


Assuntos
Coração/diagnóstico por imagem , Próstata/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adulto , Cor , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Isquemia Miocárdica/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos
2.
Biomed Res Int ; 2018: 5095673, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30420965

RESUMO

The present study aimed to evaluate the effects of two types of 9-month adapted physical activity (APA) program, based on a muscle reinforcement training and a postural training, respectively, on muscle mass, muscle strength, and static balance in moderate sarcopenic older women. The diagnosis of sarcopenia was done in accordance with measurable variables and cut-off points suggested by the European Working Group on Sarcopenia in Older People (EWGSOP). Seventy-two participants were randomly assigned to two groups: the muscle reinforcement training group (RESISTANCE) (n=35; 69.9 ± 2.7 years) and the postural training group (POSTURAL) (n=37; 70.0±2.8 years). Body composition, muscle mass, skeletal muscle mass index (SMI), and handgrip strength (HGS) were evaluated for sarcopenia assessment, whereas Sway Path, Sway Area, Stay Time, and Spatial Distance were evaluated for static balance assessment. Sixty-six participants completed the study (RESISTANCE group: n=33; POSTURAL group: n=33). Significant increases of muscle mass, SMI, and handgrip strength values were found in the RESISTANCE group, after muscle reinforcement program. No significant differences appeared in the POSTURAL group, after postural training. Furthermore, RESISTANCE group showed significant improvements in static balance parameters, whereas no significant differences appeared in the POSTURAL group. On the whole, the results of this study suggest that the APA program based on muscle reinforcement applied on moderate sarcopenic older women was able to significantly improve muscle mass and muscle strength, and it was also more effective than the applied postural protocol in determining positive effects on static balance.


Assuntos
Terapia por Exercício , Força Muscular/fisiologia , Equilíbrio Postural/fisiologia , Treinamento Resistido , Sarcopenia/terapia , Idoso , Exercício Físico/fisiologia , Feminino , Força da Mão/fisiologia , Humanos , Músculo Esquelético/fisiologia , Sarcopenia/fisiopatologia
3.
Eur J Pharm Biopharm ; 124: 55-62, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29258912

RESUMO

Sugar fatty acid esters are an interesting class of non-ionic, biocompatible and biodegradable sugar-based surfactants, recently emerged as a valid alternative to the traditional commonly employed (e.g. polysorbates and polyethylene glycol derivatives). By varying the polar head (carbohydrate moiety) and the hydrophobic tail (fatty acid), surfactants with different physico-chemical characteristics can be easily prepared. While many research papers have focused on sucrose derivatives, relatively few studies have been carried out on lactose-based surfactants. In this work, we present the synthesis and the physico-chemical characterization of lactose oleate. The new derivative was obtained by enzymatic mono-esterification of lactose with oleic acid. Thermal, surface, and aggregation properties of the surfactant were studied in detail and the cytotoxicity profile was investigated by MTS and LDH assays on intestinal Caco-2 monolayers. Transepithelial electrical resistance (TEER) measurements on Caco-2 cells showed a transient and reversible effect on the tight junctions opening, which correlates with the increased permeability of 4 kDa fluorescein-labelled dextran (as model for macromolecular drugs) in a concentration dependent manner. Moreover, lactose oleate displayed a satisfactory antimicrobial activity over a range of Gram-positive and Gram-negative bacteria. Overall, the obtained results are promising for a further development of lactose oleate as an intestinal absorption enhancer and/or an alternative biodegradable preservative for pharmaceutical and food applications.


Assuntos
Materiais Biocompatíveis , Absorção Intestinal/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Lactose/farmacologia , Ácidos Oleicos/farmacologia , Conservantes Farmacêuticos/farmacologia , Tensoativos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Células CACO-2 , Varredura Diferencial de Calorimetria , Sobrevivência Celular/efeitos dos fármacos , Composição de Medicamentos , Difusão Dinâmica da Luz , Impedância Elétrica , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Humanos , Mucosa Intestinal/metabolismo , Intestinos/patologia , Lactose/análogos & derivados , Lactose/síntese química , Lactose/toxicidade , Testes de Sensibilidade Microbiana , Ácidos Oleicos/síntese química , Ácidos Oleicos/toxicidade , Permeabilidade , Conservantes Farmacêuticos/síntese química , Conservantes Farmacêuticos/toxicidade , Propriedades de Superfície , Tensoativos/síntese química , Tensoativos/toxicidade , Tecnologia Farmacêutica/métodos , Junções Íntimas/efeitos dos fármacos , Junções Íntimas/metabolismo , Junções Íntimas/patologia
4.
J Org Chem ; 66(3): 727-32, 2001 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-11430089

RESUMO

The synthesis of two oligomers containing three and four residues, respectively, of trans-(4S,5R)-4-carboxy 5-methyloxazolidin-2-ones is described. The monomer is obtained by starting from benzyl-N-Boc-(3R)-aminobutanoate, by cyclization into the corresponding trans-(2S,3R)-2-carboxybenzyl-3-methyl-N-Boc-aziridine and rearrangement of the product to trans-(4S,5R)-4-carboxybenzyl-5- methyloxazolidin-2-one, catalyzed by Sn(OTf)2. The oligomers are synthesized by activating the carboxy group as its pentaflourophenyl ester. The trimer and the tetramer are obtained in good yield, and their 1H NMR spectra suggest that these molecules fold in ordered structures, where the C-4 hydrogen of a ring is always close to the carbonyl of the next ring. This result shows that the 4-carboxy-5-substituted-oxazolidin-2-ones are a new class of pseudoprolines which fully control the formation of a Xaai-1-Proi peptide bond in the trans conformation and are complementary to the pseudoprolines obtained from cyclocondensation of cysteine, serine, or threonine and aldehydes or ketones, which strongly favor the Xaai-1-Proi peptide bond in the cis conformation.

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