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1.
Opt Express ; 22(3): 2632-55, 2014 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-24663556

RESUMO

We demonstrate, for the first time, OCT imaging capabilities of a novel, akinetic (without any form of movement in the tuning mechanism), all-semiconductor, all-electronic tunable, compact and flexible swept source laser technology at 1550 nm and 1310 nm. To investigate its OCT performance, 2D and 3D ex vivo and in vivo OCT imaging was performed at different sweep rates, from 20 kHz up to 200 kHz, with different axial resolutions, about 10 µm to 20 µm, and at different coherence gate displacements, from zero delay to >17 cm. Laser source phase linearity and phase repeatability standard deviation of <2 mrad (<160 pm) were observed without external phase referencing, indicating that the laser operated close to the shot noise limit (~2 × factor); constant percentile wavelengths variations of sliding RIN and ortho RIN <0.2% could be demonstrated, ~5 times better as compared to other swept laser technologies.


Assuntos
Aumento da Imagem/instrumentação , Lasers Semicondutores , Lasers , Iluminação/instrumentação , Microscopia Confocal/instrumentação , Tomografia de Coerência Óptica/métodos , Desenho de Equipamento , Análise de Falha de Equipamento
2.
Osteoarthritis Cartilage ; 17(1): 33-42, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18621555

RESUMO

OBJECTIVE: To investigate a novel optical method to determine the three dimensional (3-D) structure of articular cartilage collagen non-destructively. METHODS: Polarization-sensitive optical coherence tomography was used to determine the apparent optical birefringence of articular cartilage for a number of different illumination directions. A quantitative method based on the theory of light propagation in uniaxial crystalline materials was validated on equine flexor tendon. Qualitative maps of fiber polar and azimuthal orientation at sites on the posterior and anterior segments of the equine third metacarpophalangeal (fetlock) joint were produced, and the azimuthal orientations compared with data from a split-line experiment. RESULTS: Polar and azimuthal angles of cut flexor tendon broadly agreed with the nominal values but suggested that the accuracy was limited by our method of determining the apparent birefringence. On intact equine fetlock joints we found a non-zero polar tilt that changed in direction at various points along the apex, moving from the sagittal ridge outwards. The azimuthal orientation changes from being parallel to the sagittal ridge in the posterior region to being inclined to the ridge in the anterior region. This broadly agrees with split-line data for the anterior region but differs in the posterior region, possibly reflecting depth-dependent orientation changes. CONCLUSION: General quantitative agreement was found between our method and histology in validation experiments. Qualitative results for cartilage suggest a complicated 3-D structure that warrants further study. There is potential to develop this approach into a tool that can provide depth-resolved information on collagen orientation in near real-time, non-destructively and in vivo.


Assuntos
Cartilagem Articular/química , Colágeno/análise , Animais , Cartilagem Articular/ultraestrutura , Cavalos , Imageamento Tridimensional/métodos , Microscopia de Polarização , Modelos Biológicos , Tendões/química , Tomografia de Coerência Óptica/métodos
3.
Nat Prod Res ; 32(5): 521-528, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28486828

RESUMO

Ruta chalepensis L. (Rutaceae) leaf extract was investigated for its chemical profile and antioxidant and hypoglycaemic properties. The antioxidant effects were investigated by 2,2-diphenyl-1-picrylhydrazyl (DPPH), ß-carotene bleaching, and metal chelating activity assays. The carbohydrate-hydrolysing enzymes inhibition assay was used to test the hypoglycaemic potential. R. chalepensis showed a high content of hesperidin and rutin with values of 591.9 and 266.7 mg/g dry extract, respectively. The extract exhibited a promising protection of lipid peroxidation (IC50 value of 16.9 µg/mL) and inhibited both α-amylase and α-glucosidase enzymes in a concentration-dependent manner. The highest activity was found against α-amylase (IC50 value of 69.0 µg/mL). The obtained results support the use of R. chalepensis leaves as healthy food ingredients.


Assuntos
Antioxidantes/farmacologia , Inibidores Enzimáticos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Ruta/química , Antioxidantes/química , Compostos de Bifenilo/química , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/química , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Hesperidina/análise , Hidrólise , Concentração Inibidora 50 , Peroxidação de Lipídeos/efeitos dos fármacos , Picratos/química , Folhas de Planta/química , Rutina/análise , alfa-Amilases/antagonistas & inibidores , beta Caroteno/química
4.
Food Chem Toxicol ; 106(Pt A): 155-164, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28552787

RESUMO

The aim of the present study was to investigate the in vitro antioxidant and antitumor effects of Salvia fruticosa Mill subsp. thomasii (Lacaita) Brullo, Guglielmo, Pavone & Terrasi (Lamiaceae). The aerial parts were extracted by maceration with methanol. This extract was partitioned with methanol and n-hexane. Luteolin, luteolin 7-O-glucoside, rutin and salvigenin were isolated from the methanol-soluble fraction. n-Hexane fraction showed viridiflorol, ß-pinene, 1,8-cineole, as main components. The methanol-soluble fraction exerted antitumor activity against human breast cancer (MCF-7 and MDA-MB-231) and human colorectal carcinoma (RKO and Caco-2) cells. TUNEL test revealed that S. fruticosa subsp. thomasii leads to cells death by apoptosis, with low cytotoxic effects on non-tumoral 3T3-L1 cells. Moreover, it exerted the highest protection of lipid peroxidation and reduced the oxidative stress induced by menadione treatment in 3T3-L1 murine fibroblasts. S. fruticosa subsp. thomasii bioactivity could promote its use not only as food but also in nutraceutical/pharmaceutical industries.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Extratos Vegetais/farmacologia , Salvia/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Componentes Aéreos da Planta/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação
5.
Curr Med Chem ; 22(12): 1515-38, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25723509

RESUMO

Skin aging is an inevitable biological phenomenon of human life. Advancing age brings changes to all components of the integumentary system with consequent signs on the skin. Skin aging is mainly due to intrinsic (chronologic) and extrinsic aging (photo-aging). Photo-aging is a consequence of exposure to ultraviolet radiations. Despite variable economic conditions, the skin care market based on natural products continues to see strong growth. In this context, the research of naturally occurring anti-aging agents is greatly expanding and in recent years numerous plant-derived products have been investigated. This review article focuses on highlighting recent advances in current knowledge on anti-aging natural products grouped and presented according to their family origin. Plants from 35 families were reviewed. A variety of phytomolecules, derived in particular from polyphenols, triterpenes and sterols classes, demonstrated a promising activity. Among them carnosic acid, curculigoside, curcumin, glycyrrhizic acid, mangiferin, mirkoin, asiaticoside, rosmarinic acid, tectorigenin, tyrosol etc., able to inhibit tyrosinase, hyaluronidase, elastase, and collagenase, to scavenge free radicals from skin cells, to prevent trans-epidermal water loss, and to contribute to protect skin from wrinkles, were largely investigated and herein discussed. Extracts and pure compounds from Fabaceae, Asperaceae and Zingiberaceae families have shown particular interest and appear most promising in the development of anti-aging products.


Assuntos
Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/farmacologia , Flavonoides/química , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Humanos , Magnoliopsida/química , Magnoliopsida/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/efeitos da radiação , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Plantas Medicinais/metabolismo , Polifenóis/química , Polifenóis/isolamento & purificação , Polifenóis/farmacologia , Envelhecimento da Pele/efeitos dos fármacos , Envelhecimento da Pele/efeitos da radiação , Raios Ultravioleta
6.
Phys Med Biol ; 55(13): 3777-87, 2010 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-20551504

RESUMO

The objective of this study was to develop a method based on polarization-sensitive optical coherent tomography (PSOCT) for the imaging and quantification of degenerative changes associated with Achilles tendon rupture. Ex vivo PSOCT examinations were performed in 24 patients. The study involved samples from 14 ruptured Achilles tendons, 4 tendinopathic Achilles tendons and 6 patellar tendons (collected during total knee replacement) as non-ruptured controls. The samples were imaged in both intensity and phase retardation modes within 24 h after surgery, and birefringence was quantified. The samples were fixed and processed for histology immediately after imaging. Slides were assessed twice in a blind manner to provide a semi-quantitative histological score of degeneration. In-depth micro structural imaging was demonstrated. Collagen disorganization and high cellularity were observable by PSOCT as the main markers associated with pathological features. Quantitative assessment of birefringence and penetration depth found significant differences between non-ruptured and ruptured tendons. Microstructure abnormalities were observed in the microstructure of two out of four tendinopathic samples. PSOCT has the potential to explore in situ and in-depth pathological change associated with Achilles tendon rupture, and could help to delineate abnormalities in tendinopathic samples in vivo.


Assuntos
Tendão do Calcâneo/patologia , Ruptura/patologia , Tomografia de Coerência Óptica/métodos , Tendão do Calcâneo/fisiopatologia , Tendão do Calcâneo/cirurgia , Adulto , Idoso , Colágeno/metabolismo , Humanos , Imageamento Tridimensional , Técnicas In Vitro , Pessoa de Meia-Idade , Ligamento Patelar/patologia , Ligamento Patelar/fisiopatologia , Ligamento Patelar/cirurgia , Ruptura/fisiopatologia , Ruptura/cirurgia , Tendinopatia/patologia , Tendinopatia/fisiopatologia , Tendinopatia/cirurgia , Fatores de Tempo , Adulto Jovem
7.
Phytother Res ; 18(7): 585-7, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15305322

RESUMO

The aim of this study was to evaluate the in vitro antioxidant and cytotoxic activities of the methanol extracts of Retama raetam subsp. gussonei leaves and seeds. The antioxidant activity of the extracts was assessed by means of two different tests: (1) bleaching of the stable 2,2-diphenyl-1-picrylhydrazil (DPPH) radical; and (2) lipid peroxidation of liposomes which were prepared from bovine brain extract. In both tests used leaves extract showed a significant antioxidant effect. The extract of leaves also demonstrated a good cytotoxic activity against COR-L23 (large cell carcinoma) cell line.


Assuntos
Antioxidantes/farmacologia , Fabaceae , Fitoterapia , Extratos Vegetais/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Compostos de Bifenilo , Linhagem Celular Tumoral/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Lipossomos , Picratos/química , Folhas de Planta , Sementes
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