Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Int J Mol Sci ; 25(17)2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39273119

RESUMO

Phycocyanin (PC) is a naturally occurring green pigment in Spirulina. It was extracted by ultrasonic extraction using green technology, and its structure was studied using IR- and NMR-spectroscopy. Spectral data confirmed the PC structure. This study also involves an in silico assessment of the diverse applications of green pigment PC. Utilizing QSAR, PreADME/T, SwissADME, and Pro-Tox, this study explores the safety profile, pharmacokinetics, and potential targets of PC. QSAR analysis reveals a favorable safety profile, with the parent structure and most metabolites showing no binding to DNA or proteins. PreADME/T indicates low skin permeability, excellent intestinal absorption, and medium permeability, supporting oral administration. Distribution analysis suggests moderate plasma protein binding and cautious blood-brain barrier permeability, guiding formulation strategies. Metabolism assessments highlight interactions with key cytochrome P450 enzymes, influencing drug interactions. Target prediction analysis unveils potential targets, suggesting diverse therapeutic effects, including cardiovascular benefits, anti-inflammatory activities, neuroprotection, and immune modulation. Based on the in silico analysis, PC holds promise for various applications due to its safety, bioavailability, and potential therapeutic benefits. Experimental validation is crucial to elucidate precise molecular mechanisms, ensuring safe and effective utilization in therapeutic and dietary contexts. DFT calculations, including geometry optimization, MEP analysis, HOMO-LUMO energy surface, and quantum reactivity parameters of the PC compound, were obtained using the B3LYP/6-311G(d,p) level. This integrated approach contributes to a comprehensive understanding of PC's pharmacological profile and informs future research directions.


Assuntos
Teoria da Densidade Funcional , Ficocianina , Spirulina , Spirulina/química , Ficocianina/química , Ficocianina/isolamento & purificação , Ficocianina/farmacologia , Relação Quantitativa Estrutura-Atividade , Humanos , Simulação por Computador , Barreira Hematoencefálica/metabolismo
2.
Breathe (Sheff) ; 12(2): e50-4, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27408646

RESUMO

A case report of an interesting paraneoplastic syndrome http://ow.ly/YGAR3.

3.
Breathe (Sheff) ; 11(1): 67-70, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26306105

RESUMO

A 35-year-old man presented to the accident and emergency department with history of productive cough, breathlessness and some weight loss over several weeks. He had a past medical history of asthma and eczema. He mentioned that, at times, he had been expectorating sputum with some haemoptysis over the past few months. He was of Bangladeshi origin, but had been resident in the UK since 1986 and last visited Bangladesh a year ago. He was a smoker of 10-15 cigarettes per day. He also admitted to smoking heroin. In addition to his respiratory symptoms he also complained of vomiting, which was precipitated by eating. He denied bowel or urinary symptoms.

4.
Indian J Exp Biol ; 51(1): 29-36, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23441477

RESUMO

Different concentrations of H. rhodopensis total extract (HRE; 0.03, 0.06 and 0.12 g/kg body weight) were injected im, into rabbits 2 h before collecting the blood samples. The whole blood samples were exposed in vitro to 2.0 Gy 60Co gamma-radiation. The radiation-induced changes were estimated by using the chromosome aberration test (CA) and cytokinesis blocked micronucleus assay (CBMN) in peripheral lymphocytes, and by determining the malondialdehyde levels (MDA) in blood plasma and the superoxide dismutase (SOD) and catalase (CAT) activity in erythrocytes. Radiation significantly increased the chromosome aberration and micronuclei frequencies as well as MDA levels and decreased the antioxidant enzyme activity. On the other hand, the HRE pretreatment significantly decreased the CA, MN frequencies and MDA levels and increased the SOD and CAT activity in a concentration dependent manner. The most effective was the highest concentration of HRE (0.12 g/kg body weight). The results suggest that HRE as a natural product with a nantioxidant capacity could play a modulatory role against the cellular damage induced by gamma-irradiation. The possible mechanism involved in the radioprotective potential of HRE is discussed.


Assuntos
Dano ao DNA/efeitos dos fármacos , Magnoliopsida/metabolismo , Extratos Vegetais/farmacologia , Lesões por Radiação/prevenção & controle , Animais , Antioxidantes/química , Antioxidantes/metabolismo , Catalase/metabolismo , Aberrações Cromossômicas , Meios de Cultura , Eritrócitos/citologia , Radicais Livres , Raios gama , Peroxidação de Lipídeos , Masculino , Testes para Micronúcleos/métodos , Modelos Biológicos , Coelhos , Protetores contra Radiação/farmacologia , Superóxido Dismutase/metabolismo
5.
J Neurosci ; 29(3): 727-42, 2009 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-19158299

RESUMO

Three-dimensional (3D) shape is important for the visual control of grasping and manipulation and for object recognition. Although there has been some progress in our understanding of how 3D shape is extracted from motion and other monocular cues, little is known of how the human brain extracts 3D shape from disparity, commonly regarded as the strongest depth cue. Previous fMRI studies in the awake monkey have established that the interaction between stereo (present or absent) and the order of disparity (zero or second order) constitutes the MR signature of regions housing second-order disparity-selective neurons (Janssen et al., 2000; Srivastava et al., 2006; Durand et al., 2007; Joly et al., 2007). Testing the interaction between stereo and order of disparity in a large cohort of human subjects, revealed the involvement of five IPS regions (VIPS/V7*, POIPS, DIPSM, DIPSA, and phAIP), as well as V3 and the V3A complex in occipital cortex, the posterior inferior temporal gyrus (ITG), and ventral premotor cortex (vPrCS) in the extraction and processing of 3D shape from stereo. Control experiments ruled out attention and convergence eye movements as confounding factors. Many of these regions, DIPSM, DIPSA, phAIP, and probably posterior ITG and ventral premotor cortex, correspond to monkey regions with similar functionality, whereas the evolutionarily new or modified regions are located in occipital (the V3A complex) and occipitoparietal cortex (VIPS/V7* and POIPS). Interestingly, activity in these occipital regions correlates with the depth amplitude perceived by the subjects in the 3D surfaces used as stimuli in these fMRI experiments.


Assuntos
Mapeamento Encefálico , Encéfalo/fisiologia , Percepção de Profundidade/fisiologia , Percepção de Forma/fisiologia , Disparidade Visual/fisiologia , Adulto , Encéfalo/irrigação sanguínea , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Oxigênio/sangue , Estimulação Luminosa/métodos , Psicofísica , Vias Visuais/irrigação sanguínea , Vias Visuais/fisiologia , Adulto Jovem
6.
Cereb Cortex ; 18(10): 2416-38, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18281304

RESUMO

We used functional magnetic resonance imaging to investigate the human cortical areas involved in processing 3-dimensional (3D) shape from texture (SfT) and shading. The stimuli included monocular images of randomly shaped 3D surfaces and a wide variety of 2-dimensional (2D) controls. The results of both passive and active experiments reveal that the extraction of 3D SfT involves the bilateral caudal inferior temporal gyrus (caudal ITG), lateral occipital sulcus (LOS) and several bilateral sites along the intraparietal sulcus. These areas are largely consistent with those involved in the processing of 3D shape from motion and stereo. The experiments also demonstrate, however, that the analysis of 3D shape from shading is primarily restricted to the caudal ITG areas. Additional results from psychophysical experiments reveal that this difference in neuronal substrate cannot be explained by a difference in strength between the 2 cues. These results underscore the importance of the posterior part of the lateral occipital complex for the extraction of visual 3D shape information from all depth cues, and they suggest strongly that the importance of shading is diminished relative to other cues for the analysis of 3D shape in parietal regions.


Assuntos
Percepção de Profundidade/fisiologia , Percepção de Forma/fisiologia , Imageamento por Ressonância Magnética , Lobo Parietal/fisiologia , Córtex Visual/fisiologia , Adulto , Mapeamento Encefálico , Feminino , Humanos , Masculino , Estimulação Luminosa/métodos , Psicofísica , Movimentos Sacádicos/fisiologia , Visão Binocular/fisiologia , Visão Monocular/fisiologia , Adulto Jovem
7.
J Neurosci ; 25(17): 4294-306, 2005 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-15858056

RESUMO

Functional magnetic resonance imaging in awake monkeys and humans was used to compare object adaptation in shape-sensitive regions of these two species under identical and different size conditions. Object adaptation was similar in humans and monkeys under both conditions. Neither species showed complete size invariance, in agreement with single-cell studies. Both the macaque inferotemporal (IT) complex and human lateral occipital complex (LOC) displayed an anteroposterior gradient in object adaptation and size invariance, with the more anterior regions being more adaptable and size invariant. The results provide additional evidence for the homology between the macaque IT cortex and human LOC but also add to the growing list of differences between human and monkey intraparietal sulcus regions.


Assuntos
Adaptação Fisiológica/fisiologia , Mapeamento Encefálico , Córtex Cerebral/irrigação sanguínea , Percepção de Forma/fisiologia , Imageamento por Ressonância Magnética , Reconhecimento Visual de Modelos/fisiologia , Adolescente , Adulto , Animais , Córtex Cerebral/anatomia & histologia , Córtex Cerebral/fisiologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Macaca mulatta , Masculino , Oxigênio/sangue , Estimulação Luminosa
8.
J Cogn Neurosci ; 16(9): 1505-16, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15601515

RESUMO

The prefrontal cortex supports many cognitive abilities, which humans share to some degree with monkeys. The specialized functions of the prefrontal cortex depend both on the nature of its inputs from other brain regions and on distinctive aspects of local processing. We used functional MRI to compare prefrontal activity between monkey and human subjects when they viewed identical images of objects, either intact or scrambled. Visual object-related activation of the lateral prefrontal cortex was observed in both species, but was stronger in monkeys than in humans, both in magnitude (factors 2-3) and in spatial extent (fivefold or more as a percentage of prefrontal volume). This difference was observed for two different stimulus sets, at two field strengths, and over a range of tasks. These results suggest that there may be more volitional control over visual processing in humans than in monkeys.


Assuntos
Nível de Alerta/fisiologia , Mapeamento Encefálico , Potenciais Evocados Visuais/fisiologia , Processos Mentais/fisiologia , Córtex Pré-Frontal/fisiologia , Animais , Humanos , Macaca mulatta , Imageamento por Ressonância Magnética , Masculino , Reconhecimento Visual de Modelos/fisiologia , Valores de Referência , Especificidade da Espécie
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA