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1.
ACS Nano ; 8(11): 11191-205, 2014 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-25337632

RESUMEN

We demonstrate essentially complete exfoliation of graphene aggregates in water at concentrations up to 5% by weight (166-fold greater than previous high concentration report) using recently developed triblock copolymers and copolymeric nanolatexes based on a reactive ionic liquid acrylate surfactant. We demonstrate that the visible absorption coefficient in aqueous dispersion, 48.9 ± 1.3 cm(2)/mg at 500 nm, is about twice that currently accepted, and we show that this value is a greatest lower bound to extant macroscopic single sheet optical studies of graphene when one considers both fine structure constant and excitonic mechanisms of visible absorption. We also show that dilute and concentrated graphene dispersions are rheo-optical fluids that exhibit an isotropic to nematic transition upon application of a shear field, and we demonstrate stimuli-responsive phase transfer.

2.
J Med Food ; 17(11): 1204-13, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25271471

RESUMEN

The goal for this study was to evaluate the effects of consumption of dried apple peel powder (DAPP) on joint function and range of motion (ROM). Additional in vitro and clinical testing was performed to suggest specific mechanisms of action. An open-label clinical pilot study involved 12 healthy people with moderate loss of joint ROM and associated chronic pain. The subjects consumed 4.25 g DAPP daily for 12 weeks, with evaluations at baseline, 2, 4, 8, and 12 weeks. ROM was evaluated at each visit using dual digital inclinometry. Pain scores were collected using Visual Analogue Scales. Blood draws enabled testing of serum antioxidant protective capacity using the cellular antioxidant protection (CAP-e) bioassay. Additional in vitro testing involved testing of cyclooxygenase-2 (COX-2) and lipoxygenase inhibition, cellular antioxidant protection by the CAP-e bioassay, and formation of reactive oxygen species (ROS) by polymorphonuclear (PMN) cells by flow cytometry. Twelve weeks of consumption of DAPP was associated with improved ROM. DAPP provided antioxidants that were available to enter into and protect cells from oxidative damage in vitro, and consumption of DAPP for 12 weeks was associated with a statistically significant improvement in serum antioxidant protective status. DAPP inhibited both COX-2 and lipoxygenase enzymes, and pretreatment of inflammatory PMN cells with DAPP before inflammatory stimulus resulted in reduced ROS formation. This suggests multifaceted anti-inflammatory properties of DAPP. Consumption of DAPP was associated with improved joint function and improved serum antioxidant protection status. The observed pain reduction may be associated with the improved antioxidant status and linked to the apple polyphenols' anti-inflammatory effects.


Asunto(s)
Antioxidantes/uso terapéutico , Inhibidores de la Ciclooxigenasa 2/uso terapéutico , Articulaciones/efectos de los fármacos , Malus/química , Dolor/tratamiento farmacológico , Preparaciones de Plantas/uso terapéutico , Rango del Movimiento Articular/efectos de los fármacos , Anciano , Antioxidantes/farmacología , Dolor Crónico/tratamiento farmacológico , Ciclooxigenasa 2/metabolismo , Inhibidores de la Ciclooxigenasa 2/farmacología , Femenino , Frutas/química , Humanos , Articulaciones/patología , Lipooxigenasa/metabolismo , Masculino , Persona de Mediana Edad , Movimiento , Fitoterapia , Preparaciones de Plantas/farmacología , Polifenoles/farmacología , Polifenoles/uso terapéutico
3.
Angew Chem Int Ed Engl ; 51(38): 9483-4, 2012 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-22887763
4.
Prev Med ; 54 Suppl: S83-9, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22342951

RESUMEN

OBJECTIVE: To evaluate anti-inflammatory properties of a nutraceutical blend containing L-ergothioneine in concert with other anti-inflammatory and analgesic ingredients, combined with nutritional cartilage support. METHODOLOGY: Twelve human subjects were tested over a 6-week period of product consumption followed by a 6-week wash-out period, conducted at NIS Labs during late fall/early winter 2010. Range of motion (ROM) assessment of joint motility was performed using JTECH dual digital inclinometry and included flexion, extension, and rotation through the vertical weight-bearing column (neck, thorax, lumbar, hip, knees) and shoulders. Pain evaluation included questionnaires and Visual Analogues Scales regarding primary and secondary pain complaints at rest and at use. RESULTS: ROM improvements were seen after 1 week, and further improved at 6 weeks (primary pain area P<0.2, secondary pain area P<0.03). Pain in primary and secondary areas at use was significantly reduced already at 1 week, compared to baseline (P<0.05). Pain reduction for both primary and secondary pain areas during use reached a high level of statistical significance at 6 weeks (P<0.004), and remained highly significant after the 6-week wash-out period. CONCLUSION: Pain reduction and improved ROM were observed during the 6-week consumption. Residual effects were seen 6 weeks after stopping consumption of the ergothioneine supplement.


Asunto(s)
Antioxidantes/farmacología , Dolor Crónico/tratamiento farmacológico , Ergotioneína/farmacología , Rango del Movimiento Articular/efectos de los fármacos , Adulto , Anciano , Antioxidantes/administración & dosificación , Ergotioneína/administración & dosificación , Femenino , Humanos , Entrevistas como Asunto , Masculino , Persona de Mediana Edad , Dimensión del Dolor
5.
Chem Soc Rev ; 41(8): 3340-80, 2012 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-22318431

RESUMEN

Asymmetric hydrogenations are increasingly being used to introduce stereogenic centres into products used in the life sciences industries. There are a number of potential pitfalls when moving from a laboratory reaction to a manufacturing process, not least of which is safety. Time-to-market pressure leads to short development times, which in the past could be a large barrier for the implementation of catalytic steps; now there are new ways to minimise this problem. The potential problems associated with impurities and other methods that can shut down the hydrogenation reactions are highlighted in this critical review (353 references).


Asunto(s)
Hidrogenación , Catálisis , Evaluación Preclínica de Medicamentos , Humanos , Industrias , Compuestos Orgánicos/química , Seguridad
6.
J Med Food ; 14(7-8): 702-11, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21470042

RESUMEN

Dietary interventions involving antioxidants are of interest for reducing inflammation, improving joint motion, and altering pain perception. We evaluated the effect of oral consumption of a fruit and berry blend on pain and range of motion (ROM). This open-label clinical pilot study involved 14 study participants with limitations in ROM that was associated with pain and affected daily living. Participants included but were not limited to those with age-related osteoarthritis. Study participants consumed 120 mL MonaVie Active® fruit juice, predominantly containing açai pulp (Euterpe oleracea Mart.) and other fruit concentrates, daily for 12 weeks. Study participants were assessed at baseline and 2, 4, 8, and 12 weeks by structured nurse interviews, pain and activities of daily living (ADL) questionnaires, blood samples, and ROM assessment. Pain was scored by using a visual analogue scale. ROM was assessed by using dual digital inclinometry as recommended by American Medical Association guidelines. Consumption of the juice resulted in significant pain reduction, improved ROM measures, and improvement in ADLs. Serum antioxidant status, as monitored by the cell-based antioxidant protection in erythrocytes (CAP-e) assay, was improved within 2 weeks and continued to improve throughout the 12 weeks of study participation (P<.01). The inflammatory marker C-reactive protein was reduced at 12 weeks, but this change did not reach statistical significance. Lipid peroxidation decreased mildly at 12 weeks. The antioxidant status, as measured by the CAP-e bioassay, showed the best correlation with improvements in physical well-being (pain, ROM, and ADL). The significant association among increased antioxidant status, improved ROM, and pain reduction warrants further study.


Asunto(s)
Arecaceae/química , Bebidas/análisis , Flavonoides/administración & dosificación , Dolor/dietoterapia , Fenoles/administración & dosificación , Preparaciones de Plantas/administración & dosificación , Rango del Movimiento Articular/efectos de los fármacos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Frutas/química , Humanos , Masculino , Persona de Mediana Edad , Dolor/fisiopatología , Polifenoles
8.
Curr Opin Drug Discov Devel ; 5(6): 892-905, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12478720

RESUMEN

New methods to unnatural amino acids continue to be developed. This review covers methods, published in 2001, that employ an asymmetric hydrogenation, a transition metal-catalyzed reaction, an enzymatic resolution or a chiral auxiliary.


Asunto(s)
Aminoácidos/síntesis química , Aminoácidos/metabolismo , Tecnología Farmacéutica/métodos , Animales , Humanos , Hidrogenación/efectos de los fármacos , Estereoisomerismo
9.
Chem Soc Rev ; 31(3): 195-200, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12122644

RESUMEN

Noteworthy developments of the Peterson olefination reaction are reviewed. Evidence for both concerted and stepwise mechanisms for the Peterson olefination reaction is presented. The strong affinity of the oxygen anion for the silyl moiety is emphasised when the Peterson olefination reaction takes preference over both the Julia and Wittig reactions in the presence of S- and P-stabilised silyl carbanions. Cerium-mediated Peterson methylenation reactions are discussed.

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