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1.
J Nutr Health Aging ; 19(5): 548-54, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25923485

RESUMEN

OBJECTIVES: To examine the effect of a dietary supplement containing bilberry extract (BE) on eye fatigue induced by acute video display terminal (VDT) loads. DESIGN AND SETTING: A prospective, randomized, double-blind, placebo-controlled study was performed from August 2012 to February 2013 in the Medical Corporation Jico-kai Yagi Hospital, and the Shinyokohama Shinoharaguchi Orthopedic Surgery and Dermatology Clinic, in Japan. PARTICIPANTS: Two hundred eighty-one office workers aged 20-40 years that used VDTs were screened by critical flicker fusion (CFF) and near point accommodation (NPA). INTERVENTION: The participants were randomized to either a BE (480 mg/day) or placebo (vehicle) group, and took allocated capsule, daily, for 8 weeks. MEASUREMENTS: The CFF, NPA, contrast visual acuity, functional visual acuity, keratoconjunctival epithelial damage, and fluorescein tear film break-up time were examined, and 18 subjective symptoms of eye fatigue were evaluated by questionnaire. Adverse events were reported via medical interviews. Data were collected both before and after VDT load at baseline, and 4, and 8 weeks after daily supplementation with either BE or placebo. RESULTS: Of 281 participants screened, 88 having relatively lower levels of CFF and NPA were enrolled in the study. Of these, 37 control and 43 BE group subjects completed the study. The VDT load-induced reduction in CFF was alleviated after 8 weeks of BE supplementation (95% confidence interval, 0.10-1.60; p=0.023), in contrast to placebo supplementation, while NPA variation was not. Of the subjective symptoms of eye fatigue, VDT load-induced ocular fatigue sensation, ocular pain, eye heaviness, uncomfortable sensation, and foreign body sensation were mitigated more in the BE group than in the control group, at week 8 (p<0.05). There were no severe adverse events in either group. CONCLUSIONS: BE supplementation improved some of the objective and subjective parameters of eye fatigue induced by VDT loads.


Asunto(s)
Astenopía/dietoterapia , Astenopía/prevención & control , Terminales de Computador , Suplementos Dietéticos , Extractos Vegetales/farmacología , Vaccinium myrtillus/química , Agudeza Visual/efectos de los fármacos , Agudeza Visual/fisiología , Adulto , Astenopía/patología , Astenopía/fisiopatología , Conjuntiva/efectos de los fármacos , Conjuntiva/patología , Suplementos Dietéticos/efectos adversos , Método Doble Ciego , Femenino , Humanos , Japón , Masculino , Extractos Vegetales/efectos adversos , Encuestas y Cuestionarios , Lágrimas , Adulto Joven
2.
J Int Med Res ; 33(3): 295-300, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15938590

RESUMEN

We developed a system to measure nitric oxide (NO) concentration during cardiopulmonary bypass in anaesthetized pigs (n = 6). A T-shaped connector, attached to an NO sensor, was mounted in the extracorporeal circuit at two measuring sites: proximal to the membrane oxygenator (venous side) and distal to the arterial line filter (arterial side). After performing a preliminary validation study, we measured plasma NO concentration before and during total cardiopulmonary bypass circulation (non-pulsatile flow 1.5 l/min) and without pulmonary ventilation. After establishing bypass, PaO2 was 318 - 393 mmHg; when PaO2 was decreased to 80 - 100 mmHg, plasma NO concentration in the arterial circuit fell by 39.2 +/- 15.6 nM. There was no observable change in plasma NO concentration at the venous circuit. This new system could be useful in monitoring NO concentration during cardiac surgery with cardiopulmonary bypass, and for understanding the possible pathophysiological roles of hyper-nitric oxaemia in cardiopulmonary bypass-related cardiovascular complications.


Asunto(s)
Puente Cardiopulmonar/métodos , Óxido Nítrico/análisis , Animales , Procedimientos Quirúrgicos Cardíacos/métodos , Modelos Animales de Enfermedad , Circulación Extracorporea , Oxigenación por Membrana Extracorpórea , Óxido Nítrico/química , Óxido Nítrico/metabolismo , Oxígeno/metabolismo , Oxigenadores , Porcinos , Tromboembolia/cirugía
3.
Chem Pharm Bull (Tokyo) ; 45(10): 1631-41, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9353891

RESUMEN

A series of renin inhibitors containing the (2S,3S,5S)-2-amino-1-cyclohexyl-6-methyl-3,5-heptanediol (2-amino-3,5-anti-diol) fragment as a novel transition-state mimic was synthesized, and their biological activities were evaluated. All of the synthesized compounds containing the 2-amino-3,5-anti-diol fragment at the P1-P1' position showed high in vitro renin-inhibitory activity with IC50 values in the 10(-8)-10(-10) M range, and most of them caused a reduction of blood pressure when administered orally to salt-depleted, conscious marmosets. The inhibitor (29) with the 4-hydroxypiperidine residue at the P4 position showed the highest activity in terms of both potency and duration of the blood pressure-lowering effect.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/síntesis química , Antihipertensivos/síntesis química , Presión Sanguínea/efectos de los fármacos , Dipéptidos/química , Alcoholes Grasos/química , Renina/antagonistas & inhibidores , Administración Oral , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Animales , Antihipertensivos/farmacología , Callithrix , Catepsina D/antagonistas & inhibidores , Humanos , Espectroscopía de Resonancia Magnética , Pepsina A/antagonistas & inhibidores , Renina/sangre , Sistema Renina-Angiotensina/efectos de los fármacos , Cloruro de Sodio , Especificidad de la Especie , Espectrometría de Masa Bombardeada por Átomos Veloces , Relación Estructura-Actividad
4.
Cell ; 90(6): 1085-95, 1997 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-9323136

RESUMEN

Hematopoietic prostaglandin (PG) D synthase is the key enzyme for production of the D and J series of prostanoids in the immune system and mast cells. We isolated a cDNA for the rat enzyme, crystallized the recombinant enzyme, and determined the three-dimensional structure of the enzyme complexed with glutathione at 2.3 A resolution. The enzyme is the first member of the sigma class glutathione S-transferase (GST) from vertebrates and possesses a prominent cleft as the active site, which is never seen among other members of the GST family. The unique 3-D architecture of the cleft leads to the putative substrate binding mode and its catalytic mechanism, responsible for the specific isomerization from PGH2 to PGD2.


Asunto(s)
Oxidorreductasas Intramoleculares , Isomerasas/química , Isomerasas/genética , Animales , Sitios de Unión/fisiología , Clonación Molecular , Cristalografía , ADN Complementario , Epoprostenol/metabolismo , Regulación Enzimológica de la Expresión Génica , Hematopoyesis/fisiología , Isomerasas/metabolismo , Isomerismo , Lipocalinas , Datos de Secuencia Molecular , Prostaglandina D2/química , Prostaglandina D2/metabolismo , Prostaglandina H2 , Prostaglandinas H/química , Prostaglandinas H/metabolismo , Estructura Terciaria de Proteína , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Homología de Secuencia de Aminoácido , Especificidad por Sustrato , Tromboxano A2/metabolismo
5.
J Mol Biol ; 274(1): 16-20, 1997 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-9398511

RESUMEN

The crystal structure of recombinant human annexin V complexed with K-201, an inhibitor of the calcium ion channel activity of annexin V, was solved at 3.0 A by molecular replacement including the apo and high-calcium forms. K-201 was bound at the hinge region cavity formed by the N-terminal strand and domains II, III and IV, at the side opposite the calcium and membrane-binding surface, in an L-shaped conformation. Based on the complex and other annexin structures, K-201 is proposed to restrain the hinge movement of annexin V in an allosteric manner, resulting in the inhibition of calcium movement across the annexin V molecule.


Asunto(s)
Anexina A5/química , Bloqueadores de los Canales de Calcio/química , Canales de Calcio/efectos de los fármacos , Tiazepinas/química , Anexina A5/genética , Anexina A5/metabolismo , Cristalografía por Rayos X , Humanos , Ligandos , Modelos Moleculares , Unión Proteica , Proteínas Recombinantes/química , Espectrometría de Fluorescencia , Tiazepinas/metabolismo
6.
Eur J Biochem ; 225(1): 369-74, 1994 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-7925458

RESUMEN

We have determined the crystal structure of alpha-pokeweed antiviral protein, a member of ribosome-inactivating proteins, at 0.23 nm resolution, by the molecular-replacement method. The crystals belong to the space group P2(1)2(1)2 with unit-cell dimensions a = 4.71, b = 11.63 and c = 4.96 nm, and contain one protein molecule/asymmetric unit based on a crystal volume/unit protein molecular mass of 2.1 x 10(-3) nm3/Da. The crystallographic residual value was reduced to 17.2% (0.6-0.23 nm resolution) with root-mean-square deviations in bond lengths of 1.9 pm and bond angles of 2.2 degrees. The C alpha-C alpha distance map shows that alpha-pokeweed antiviral protein is composed of three modules, the N-terminal (Ala1-Leu76), the central (Tyr77-Lys185) and the C-terminal (Tyr186-Thr266) modules. The substrate-binding site is formed as a cleft between the central and C-terminal modules and all the active residues exist on the central module. The electrostatic potential around the substrate-binding site shows that the central and C-terminal module sides of this cleft have a negatively and a positively charged region, respectively. This charge distribution in the protein seems to provide a suitable interaction with the substrate rRNA.


Asunto(s)
Antivirales/química , N-Glicosil Hidrolasas , Proteínas de Plantas/química , Estructura Secundaria de Proteína , Secuencia de Aminoácidos , Sitios de Unión , Clonación Molecular , Cristalografía por Rayos X/métodos , Modelos Moleculares , Datos de Secuencia Molecular , Proteínas de Plantas/biosíntesis , Proteínas de Plantas/metabolismo , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Proteínas Inactivadoras de Ribosomas Tipo 1 , Homología de Secuencia de Aminoácido
7.
Carbohydr Res ; 251: 203-12, 1994 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-8149373

RESUMEN

Erlose [beta-D-fructofuranosyl O-alpha-D-glucopyranosyl-(1-->4)-D-glucopyranoside] trihydrate, C18H32 O16.3H2O, M(r) = 558.48, is orthorhombic, P2(1)2(1)2(1) with a = 31.164(7), b = 13.111(5), c = 11.636(5) A, and Z = 8. The structure was solved by direct methods, and refined to R = 0.035 for 3926 observed reflections. The unit cell contains two independent molecules having a similar conformation. The conformation of the alpha-(1-->2) glycosidic linkage is similar to that observed in erlose monohydrate, whereas the conformation of the alpha-(1-->4) glycosidic linkage differs significantly. The molecule has no intramolecular hydrogen-bonds except for the minor components of three-center bonds, but indirect intramolecular hydrogen-bonds through the water molecules are formed. The hydrogen-bond system in the crystal structure consists of infinite and finite chains crosslinked by water molecules.


Asunto(s)
Cariostáticos/química , Edulcorantes/química , Trisacáridos/química , Conformación de Carbohidratos , Secuencia de Carbohidratos , Cristalografía por Rayos X , Enlace de Hidrógeno , Modelos Químicos , Modelos Moleculares , Datos de Secuencia Molecular , Agua/química
8.
Carbohydr Res ; 241: 63-9, 1993 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-8472262

RESUMEN

The crystal and molecular structure of beta-D-fructofuranosyl alpha-D-xylopyranoside (xylosucrose) hemihydrate, C11H20O10.0.5H2O, is orthorhombic, P2(1)2(1)2, with a = 20.919(5), b = 18.727(2), c = 7.071(1) A, V = 2770.1(2) A3, Z = 8, and Dx = 1.541 g.cm-3. The structure was solved by direct methods and refined to R = 0.040 for 2564 observed reflections. Two independent xylosucrose molecules exist in the unit cell, and their conformations about the 1-->2' glycosidic bond are similar to sucrose. The orientations of the primary hydroxyl groups in the two molecules differ. An O-1'...O-2 intramolecular hydrogen bond was observed in the one molecule, while an O-6'...O-5 intramolecular hydrogen bond was observed in the other involving disorder of O-6'.


Asunto(s)
Sacarosa/análogos & derivados , Secuencia de Carbohidratos , Enlace de Hidrógeno , Modelos Moleculares , Datos de Secuencia Molecular , Sacarosa/química , Difracción de Rayos X
9.
Carbohydr Res ; 240: 39-45, 1993 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-8458014

RESUMEN

Erlose [O-beta-D-fructofuranosyl-(1-->2)-O-alpha-D-glucopyranosyl-(1-->4)- alpha-D-glucopyranoside] monohydrate, C18H32O16.H2O, M(r) = 522.45, is orthorhombic, P2(1)2(1)2(1) with a = 30.748 (3), b = 8.757 (1), c = 8.270 (1) A, and Z = 4. The structure was solved by direct methods, and refined to R = 0.048 for 1909 observed reflections. The torsion angles about the (1-->2) and (1-->4) glycosidic bonds are similar to those observed in other sucrose- and maltose-like oligosaccharides. The maltose moiety has an O-3'-H...O-2 intramolecular hydrogen-bond, but the sucrose moiety has no intramolecular hydrogen bonds. The hydrogen bonding in the crystal includes infinite and finite chains crosslinked by the water molecule.


Asunto(s)
Edulcorantes/química , Trisacáridos/química , Conformación de Carbohidratos , Secuencia de Carbohidratos , Enlace de Hidrógeno , Datos de Secuencia Molecular , Difracción de Rayos X
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