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1.
Appl Opt ; 53(31): 7230-5, 2014 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-25402881

RESUMEN

It is known that liquid crystal (LC) cells are useful as compact and easy-to-handle phase shifters that are readily coupled into the optics of standard microscope systems. Here, a uniformly aligned molecular LC phase shifter is introduced into a polarization microscope to attain a birefringence imaging system, using the phase-shift interferometric technique. Since the birefringence can be determined accurately only when the optical axis of the sample is parallel or perpendicular to the slow axis (variable axis) of the LC phase shifter, an improved data analysis method is proposed for determining the birefringence independently of the direction; a simple method of determining the slow axis distribution is also demonstrated. Measurements of the birefringence and slow axis distribution properties of a potato starch particle are demonstrated to confirm the novel determination method.


Asunto(s)
Interferometría/instrumentación , Cristales Líquidos/química , Microscopía de Contraste de Fase/instrumentación , Refractometría/instrumentación , Solanum tuberosum/química , Almidón/química , Almidón/ultraestructura , Birrefringencia , Diseño de Equipo , Análisis de Falla de Equipo , Imagen Molecular/instrumentación
2.
Artículo en Inglés | MEDLINE | ID: mdl-22461840

RESUMEN

Acupuncture, an alternative medicine, has been widely applied for people with sleep disturbances; therefore, the effects should be evaluated objectively. Micro-minipigs (MMPigs), the smallest miniature pigs for animal experiments, were used. Acupuncture was performed at two different points: Dafengmen is located on the head and is an anatomically similar point to human-Baihui (GV20), an effective acupoint for sleep disturbances in humans; pig-Baihui is on the back. The procedure was performed as follows: shallow, within 5 mm depth for several seconds; deep, 10-20 mm depth for 20 min. The sleep conditions were evaluated by actigraph, and the amount of catecholamine in pooled urine after acupuncture treatment. MMPigs with deep acupuncture at Dafengmen showed significantly efficient values on actigraph and catecholamine analysis as compared with untreated MMPigs. The effective acupoint for sleep conditions in the porcine model is at an anatomically similar point to humans, rather than the point determined by traditional Chinese medicine.

3.
Biochim Biophys Acta ; 1792(11): 1087-93, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19744557

RESUMEN

Carnitine-deficient juvenile visceral steatosis (JVS) mice, suffering from fatty acid metabolism abnormalities, have reduced locomotor activity after fasting. We examined whether JVS mice exhibit specific defect in the feeding response to fasting, a key process of anti-famine homeostatic mechanism. Carnitine-deficient JVS mice showed grossly defective feeding response to 24 h-fasting, with almost no food intake in the first 4 h, in marked contrast to control animals. JVS mice also showed defective acyl-ghrelin response to fasting, less suppressed leptin, and seemingly normal corticotropin-releasing factor (CRF) expression in the hypothalamus despite markedly increased plasma corticosterone. The anorectic response was ameliorated by intraperitoneal administration of carnitine or acyl-ghrelin, with decreased CRF expression. Intracerebroventricular treatment of CRF type 2 receptor antagonist, anti-sauvagine-30, recovered the defective feeding response of 24 h-fasted JVS mice. The defective feeding response to fasting in carnitine-deficient JVS mice is due to the defective acyl-ghrelin and enhanced CRF signaling in the hypothalamus through fatty acid metabolism abnormalities. In this animal model, carnitine normalizes the feeding response through an inhibition of CRF.


Asunto(s)
Carnitina/deficiencia , Ayuno/metabolismo , Ácidos Grasos/metabolismo , Hígado Graso/metabolismo , Conducta Alimentaria , Animales , Hormona Liberadora de Corticotropina/metabolismo , Modelos Animales de Enfermedad , Hígado Graso/genética , Hígado Graso/fisiopatología , Ghrelina/metabolismo , Hipotálamo/metabolismo , Hipotálamo/fisiopatología , Leptina/metabolismo , Ratones , Ratones Mutantes , Receptores de Hormona Liberadora de Corticotropina/metabolismo
4.
Free Radic Res ; 43(10): 922-31, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19680996

RESUMEN

Dehydroepiandrosterone (DHEA), a reversible inhibitor of glucose-6-phosphate dehydrogenase (G6PD), is increasingly taken as an antioxidative and anti-ageing supplement. This study investigated the effects of DHEA on the expression of G6PD and on the state of oxidative stress in a human promyelocytic leukaemia cell line, HL60, during the differentiation to neutrophil-like cell. This study differentiated HL60 with dimethyl sulfoxide (DMSO) in the presence (DMSO-HL60/DHEA) or absence (DMSO-HL60) of DHEA. During the differentiation, activity, mRNA and protein levels of G6PD were increased. DHEA increased these levels further. DHEA by itself suppressed the production of superoxide from DMSO-HL60 upon stimulation with phorbol myristate acetate (PMA). However, DMSO-HL60/DHEA stimulated with PMA in the absence of DHEA produced superoxide and 8-oxo-deoxyguanosine more than PMA-stimulated DMSO-HL60. After addition of H(2)O(2), the ratio of reduced glutathione to oxidized glutathione was lower in DMSO-HL60/DHEA than in DMSO-HL60. These findings indicate that DHEA acts both as an antioxidant and as a pro-oxidant.


Asunto(s)
Deshidroepiandrosterona/farmacología , Glucosafosfato Deshidrogenasa/antagonistas & inhibidores , Estrés Oxidativo/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/fisiología , Procesos de Crecimiento Celular/efectos de los fármacos , Procesos de Crecimiento Celular/fisiología , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Dimetilsulfóxido/farmacología , Glucosafosfato Deshidrogenasa/biosíntesis , Glucosafosfato Deshidrogenasa/genética , Glucosafosfato Deshidrogenasa/metabolismo , Células HL-60 , Humanos , NADPH Oxidasas/metabolismo , NADPH Oxidasas/farmacología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Especies Reactivas de Oxígeno/metabolismo
5.
Biochem Biophys Res Commun ; 297(5): 1238-44, 2002 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-12372420

RESUMEN

The aim of this work was to characterize folates modified by ONOO(-) and HOCl and to evaluate the binding capacity of folates modified by ONOO(-) to folate receptor alpha and beta. For the modification of folate by ONOO(-), folic acid was reacted with the combination of PMA activated PMN and PAPA NONOate or chemically synthesized ONOO(-). For the modification of folate by HOCl, folic acid was reacted with the combination of MPO and H(2)O(2) or NaOCl. The structures of products were determined by 1H-NMR and MALDI-TOF mass. Nitrated folate species were identified as 10-nitro-folate and 12-nitro-folate, and chlorinated folate was identified as 12-chloro-folate. The 10-nitro-folate showed the selective binding to FR-beta, compared to folic acid.


Asunto(s)
Proteínas Portadoras/metabolismo , Cloro/metabolismo , Ácido Fólico/química , Ácido Fólico/metabolismo , Ácido Hipocloroso/farmacología , Nitrógeno/metabolismo , Ácido Peroxinitroso/farmacología , Receptores de Superficie Celular , Línea Celular , Cromatografía Líquida de Alta Presión , ADN Complementario/metabolismo , Citometría de Flujo , Receptores de Folato Anclados a GPI , Ácido Fólico/análogos & derivados , Ácido Fólico/farmacología , Humanos , Espectroscopía de Resonancia Magnética , Modelos Químicos , Neutrófilos/metabolismo , Oxidantes/química , Unión Proteica , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Acetato de Tetradecanoilforbol/farmacología , Factores de Tiempo , Transfección , Rayos Ultravioleta
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