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1.
J Nanosci Nanotechnol ; 15(1): 562-5, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26328402

RESUMEN

White organic light-emitting devices (WOLEDs) were fabricated utilizing blue and red emitting organic light-emitting devices and a color conversion layer (CCL) made of yttrium aluminum garnet (YAG:Ce3+) phosphors embedded into polymethylmethacrylate. The good color balance for the color conversion of the WOLEDs was achieved utilizing 20-nm blue and 10-nm red OLEDs. The electroluminescence spectrum for the fabricated device showed a white color consisting of the blue color from the 4,4-bis(2,2-diphenylethen-1-yl)bipheny layer, the red color from the tris-(8-hydroxyquinolinato) aluminum: 4-(dicyanomethylene)-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran layer, and the green color from the YAG:Ce3+ phosphor. The Commission Internationale de l'Eclairage coordinates of the WOLEDs slightly shifted from (0.25, 0.23) of the blue and red emission OLEDs without phosphors to (0.34, 0.35) of the OLEDs with green phosphors, indicative of the pure white color. WOLEDs with a CCL exhibited three wavelength white emissions with a color rendering index of 86.

2.
J Nanosci Nanotechnol ; 13(6): 4390-3, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23862508

RESUMEN

White organic light-emitting devices (WOLEDs) were fabricated by combining a blue emitting organic light-emitting devices (OLEDs) and a color conversion layer made of yttrium aluminum garnet phosphors and CdSe/ZnS quantum dots (QDs) embedded into polymethylmethacrylate. When the ratio of phosphors and QDs changed, a good color balance was achieved at a ratio of 1:5, and the maximum luminance of 18.21 cd/m2 was obtained. As the applied voltage varied from 12 to 16 V, Commission Internationale de l'Eclairage coordinates shifted only slightly from (0.32, 0.34) to (0.30, 0.33), indicating a good color stability.

3.
J Nanosci Nanotechnol ; 13(6): 4394-7, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23862509

RESUMEN

White organic light-emitting devices (OLEDs) were fabricated by combining a blue OLED with a color conversion layer made of mixed Y3Al5O12:Ce3+ green and Ca2AlO19:Mn4+ red phosphors. The X-ray diffraction patterns showed that Ce3+ ions in the Y3Al5O12:Ce3+ phosphors completely substituted for the Y3+ ions and the Mn4+ ions in the CaAl12O19:Mn4+ phosphors completely substituted for the Ca2+ ions. Electroluminescence spectra at 11 V for the OLEDs fabricated utilizing a color conversion layer showed that the Commission Internationale de l'Eclairage coordinates for the Y3Al5O12:Ce3+ and CaAl12O19:Mn4+ phosphors mixed at the ratio of 1:5 and 1:10 were (0.31, 0.34) and (0.32, 0.37), respectively, indicative of a good white color.

4.
J Nanosci Nanotechnol ; 12(2): 1654-7, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22630022

RESUMEN

The optical properties of white organic light-emitting devices (WOLEDs) fabricated utilizing a CaAl12O19:Mn and Zn2SiO4:Mn phosphor layer were investigated. X-ray diffraction patterns for CaAl12O19:Mn and Zn2SiO4:Mn phosphors showed that Mn ions in the CaAl12O19:Mn phosphors were completely substituted into Ca ions and that Mn ions in the Zn2SiO4:Mn phosphors were completely substituted into Zn ions. Field emission scanning electron microscopy images showed that the size of the CaAl12O19:Mn phosphor was approximately between 0.1 and 3 microm, and that the size of the Zn2SiO4:Mn phosphor was smaller than 7 microm. The color coordinates of the electroluminescence spectra for WOLEDs with phosphor thicknesses of 0.25 and 0.35 mm shifted to the white emission side because the generated blue light from the blue OLEDs combined with the red and green lights was converted by the CaAl12O19:Mn and the Zn2SiO4:Mn phosphor down-conversion layers.

5.
Neuroscience ; 218: 216-25, 2012 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-22626645

RESUMEN

In the present study, withdrawal symptoms induced by morphine or ß-endorphin administered intracerebroventricularly (i.c.v.) were compared in ICR mice. Naloxone (10mg/kg) was post-treated intraperitoneally (i.p.) 3h after either a single or repeated (1 time/day for 3 days) i.c.v. injections with opioids. Withdrawal symptoms such as jumping frequency, diarrhea, weight loss, rearing, penile licking and paw tremor were observed for 30 min immediately after naloxone treatment. Withdrawal symptoms (jumping, diarrhea, weight loss, rearing, penile licking and paw tremor) observed in the group treated with morphine was persistently increased during 3 days. On the other hand, withdrawal symptoms such as diarrhea, weight loss and rearing in ß-endorphin-treated group were increased after a single injection with ß-endorphin, but gradually decreased after the repeated injection. Furthermore, no jumping behavior, penile licking and paw tremor in ß-endorphin-treated group were observed throughout the whole period of time. In addition, the hypothalamic changes of several signal molecules such as pERK, pCaMK-IIα, c-FOS and pCREB expression were observed during the presence or absence of withdrawal responses induced by morphine or ß-endorphin administered once or repeatedly. Both hypothalamic pCaMK-IIα and c-FOS expressions were increased by naloxone treatment in acutely administered morphine group, whereas only pCaMK-IIα expression was elevated by naloxone treatment in repeatedly administered morphine group. In contrast with the findings in morphine-treated group, only pCaMK-IIα expression was decreased by naloxone treatment in repeatedly administered ß-endorphin group. Our results suggest that profiles of the withdrawal symptoms induced by morphine and ß-endorphin administered supraspinally appear to be differentially regulated. The pCaMK-IIα and the c-FOS protein expression may play important roles for the regulation of naloxone-precipitated withdrawal symptoms such as jumping, diarrhea, weight loss, rearing, penile licking and paw tremor induced by morphine-treated group, whereas the phosphorylation of hypothalamic pCaMK-IIα appears to be involved only in the regulation of naloxone-precipitated withdrawal symptoms such as diarrhea, weight loss and rearing in ß-endorphin-treated group.


Asunto(s)
Hipotálamo/efectos de los fármacos , Morfina/administración & dosificación , Narcóticos/administración & dosificación , Síndrome de Abstinencia a Sustancias , betaendorfina/administración & dosificación , Animales , Western Blotting , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/biosíntesis , Hipotálamo/metabolismo , Inyecciones Intraventriculares , Masculino , Ratones , Ratones Endogámicos ICR , Proteínas Proto-Oncogénicas c-fos/biosíntesis , Síndrome de Abstinencia a Sustancias/metabolismo
6.
J Physiol Pharmacol ; 63(1): 87-94, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22460465

RESUMEN

It is important to understand the mechanism on the fluid shift and volume regulation occurring in astronauts after spaceflight for future life in space. In the present study, we examined the time-dependent alteration of anti-diuretic hormone (ADH) concentrating on the water reabsorption system in hindlimb unloaded rats. Male Sprague-Dawley rats were hindlimb unloaded for 1 (HU1), 7(HU7), 14 days (HU14) or rested in the ground for 3 days after HU14 (HU14+3). The plasma ADH and angiotensin II level showed peak value at HU7, and the alterations were restored at HU14. However, several serum electrolytes (Na, K, Cl) were not changed regardless of HU period. In the immunohistochemical study, we examined that ADH and c-Fos immunoreactivities (IR) were maximized at HU7 in the paraventricular nucleus (PVN) and supraoptic nucleus (SON). Aquaporin 2 (AQP2) IR also was increased in the renal collecting duct for water re-absorption at HU7 showing a similar pattern with ADH. These results present a series of physiological ADH system alteration following to period of hindlimb unloading stimulus, indicating that ADH system is activated significantly at HU7. In addition, our results suggest that ADH system activation may be involved in anti-diuretic phenomenon in early spaceflight period. Furthermore, it is speculated that ADH system may require 14 days for adaptation to microgravity.


Asunto(s)
Suspensión Trasera/fisiología , Vasopresinas/sangre , Vasopresinas/metabolismo , Angiotensina II/sangre , Animales , Acuaporina 2/metabolismo , Nitrógeno de la Urea Sanguínea , Peso Corporal/fisiología , Creatinina/metabolismo , Diuréticos , Electrólitos/sangre , Túbulos Renales/metabolismo , Masculino , Núcleo Hipotalámico Paraventricular/metabolismo , Proteínas Proto-Oncogénicas c-fos/metabolismo , Ratas , Ratas Sprague-Dawley , Núcleo Supraóptico/metabolismo , Agua/metabolismo
7.
Neuroscience ; 165(4): 1333-44, 2010 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-19961903

RESUMEN

It has been reported that glucocorticoid (Gc) can induce neuronal cell toxicity in the hippocampus. In addition, we examined that serum Gc increased by restraint stress aggravated kainic acid (KA)-induced neuronal death in hippocampal CA3 region. However, the effect of other stressful stimulus like lipopolysaccharide (LPS) increasing serum Gc on KA-induced neuronal death was not elucidated until now. Thus, we examined the time course effect of LPS on KA-induced neuronal death in the hippocampal CA3 region of mice, especially to address the role of Gc and inflammatory mediators. In the present study, we found that an aggravating effect of LPS on KA-induced neuronal death was correlated with an alteration of hippocampal IL-1beta mRNA level at all time points, and the serum Gc and hippocampal IL-1beta mRNA level was peak at 90 min after LPS treatment (LPS 90 min) when the aggravating effect of LPS on KA-induced neuronal death was maximum. In addition, RU38486 (glucocorticoid receptor antagonist) decreased the hippocampal IL-1beta mRNA level and abolished the aggravating effect of LPS on KA-induced neuronal death at LPS 90 min and 24 h. In the immunohistochemical study, we found activated and ramified microglia (OX-42) and astrocyte (GFAP) at 24 h after LPS treatment (LPS 24 h) in the hippocampus. These results suggest that Gc itself, cytokines triggered by Gc, or both appears to be involved in the LPS effect depending on LPS pretreatment time.


Asunto(s)
Región CA3 Hipocampal/efectos de los fármacos , Agonistas de Aminoácidos Excitadores/toxicidad , Ácido Kaínico/toxicidad , Lipopolisacáridos/toxicidad , Neuronas/efectos de los fármacos , Animales , Astrocitos/efectos de los fármacos , Astrocitos/fisiología , Región CA3 Hipocampal/fisiopatología , Muerte Celular/efectos de los fármacos , Muerte Celular/fisiología , Corticosterona/sangre , Corticosterona/metabolismo , Citocinas/metabolismo , Interleucina-1beta/metabolismo , Masculino , Ratones , Ratones Endogámicos ICR , Microglía/efectos de los fármacos , Microglía/fisiología , Mifepristona/farmacología , Neuroinmunomodulación/efectos de los fármacos , Neuroinmunomodulación/fisiología , Neuronas/fisiología , ARN Mensajero/metabolismo , Receptores de Glucocorticoides/antagonistas & inhibidores , Receptores de Glucocorticoides/metabolismo , Factores de Tiempo
8.
Neuroscience ; 156(3): 436-49, 2008 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-18771711

RESUMEN

In the present study, we characterized differential expressions of phosphorylated Ca(2+)/calmodulin-dependent protein kinase IIalpha (pCaMKIIalpha) and phosphorylated extracellular signal-regulated protein (pERK) in the mouse hippocampus induced by various nociceptive stimuli. In an immunoblot study, s.c. injection of formalin and intrathecal (i.t.) injections of glutamate, tumor necrosis factor-alpha (TNF-alpha), and interleukin-1beta (IL-1 beta) significantly increased pCaMKIIalpha expression in the hippocampus, but i.p. injections of acetic acid did not. pERK1/2 expression was also increased by i.t. injection of glutamate, TNF-alpha, and IL-1beta but not by s.c. injections of formalin or i.p. injections of acetic acid. In an immunohistochemical study, we found that increased pCaMKIIalpha and pERK expressions were mainly located at CA3 or the dentate gyrus of the hippocampus. In a behavioral study, we assessed the effects of PD98059 (a MEK 1/2 inhibitor) and KN-93 (a CaMKII inhibitor) following i.c.v. administration on the nociceptive behaviors induced by i.t. injections of glutamate, pro-inflammatory cytokines (TNF-alpha or IL-1beta), and i.p. injections of acetic acid. PD98059 as well as KN-93 significantly attenuated the nociceptive behavior induced by glutamate, pro-inflammatory cytokines, and acetic acid. Our results suggest that (1) pERKalpha and pCaMK-II located in the hippocampus are important regulators during the nociceptive processes induced by s.c. formalin, i.t. glutamate, i.t. pro-inflammatory cytokines, and i.p. acetic acid injection, respectively, and (2) the alteration of pERK and pCaMKIIalpha in nociceptive processing induced by formalin, glutamate, pro-inflammatory cytokines and acetic acid was modulated in a different manner.


Asunto(s)
Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Hipocampo/enzimología , Dolor/metabolismo , Ácido Acético , Análisis de Varianza , Animales , Conducta Animal , Bencilaminas/farmacología , Flavonoides/farmacología , Formaldehído , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Ácido Glutámico , Hipocampo/efectos de los fármacos , Interleucina-1beta , Masculino , Ratones , Ratones Endogámicos ICR , Dolor/inducido químicamente , Dimensión del Dolor/métodos , Fosforilación , Inhibidores de Proteínas Quinasas/farmacología , Sulfonamidas/farmacología , Factores de Tiempo , Factor de Necrosis Tumoral alfa
9.
Neuroscience ; 154(2): 415-23, 2008 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-18456411

RESUMEN

Nicotine is attractive as an analgesic component despite that its antinociceptive mechanism is not well known until now. In the present study, we examined the antinociceptive effect of nicotine administered supra-spinally on acetic acid-induced visceral pain induction (writhing test), and found that the antinociceptive effect of nicotine was abolished by mu-, delta-, and kappa-opioid receptor antagonist administered i.c.v. In addition, s.c. 5% formalin pretreatment at 5 h, 20 h, 40 h, and 1 week prior to i.c.v. nicotine injection abolished the antinociceptive effect of nicotine in the writhing test, suggesting that s.c. formalin pretreatment induced tolerance to the antinociceptive effect of nicotine in the supra-spinal region. Furthermore, neuronal loss of the hippocampal cornus ammonis (CA) 3 region reduced nicotine-induced an antinociceptive effect in the writhing test. In Western blot assay, we examined s.c. formalin injection down-regulated mu-opioid receptor in the hippocampus after 40 h, and its effect was maintained for 1 week. However, various acetylcholine receptor subunits and delta-, and kappa-opioid receptors were not altered. These results suggest that s.c. formalin pretreatment can contribute to induce tolerance on nicotine-induced antinociception as down-regulating mu-opioid receptor in the hippocampus, especially 40 h after s.c. formalin injection.


Asunto(s)
Analgésicos , Hipocampo/fisiología , Nicotina/farmacología , Agonistas Nicotínicos/farmacología , Dolor/tratamiento farmacológico , Dolor/prevención & control , Receptores Opioides mu/fisiología , Ácido Acético , Animales , Benzoxazinas , Western Blotting , Encéfalo/patología , Colorantes , Tolerancia a Medicamentos , Formaldehído , Hipocampo/efectos de los fármacos , Inmunohistoquímica , Inyecciones Intraventriculares , Masculino , Ratones , Ratones Endogámicos ICR , Antagonistas de Narcóticos/farmacología , Proteínas del Tejido Nervioso/metabolismo , Oxazinas , Dolor/patología , Dimensión del Dolor/efectos de los fármacos , Receptores Nicotínicos/efectos de los fármacos , Receptores Opioides mu/efectos de los fármacos
10.
Neuroscience ; 152(4): 1054-66, 2008 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-18329177

RESUMEN

We examined proopiomelanocortin (POMC) mRNA and beta-endorphin expression in the hypothalamus of mice after various nociceptive stimuli. The time-course study (10 min, 30 min, 1 h, 2 h, and 10 h) showed that the POMC mRNA level significantly increases from 1 h after s.c. formalin injection and returns to the control level at 10 h. Intrathecal (i.t.) substance P (SP) injection also increases the hypothalamic POMC mRNA level from 1 h to 10 h. However, i.t. glutamate injection did not affect the hypothalamic POMC gene expression at all time points. We found that the POMC mRNA after s.c. formalin injection was located in the arcuate nucleus of the hypothalamus. In the same manner, beta-endorphin immunoreactivity was also increased in the hypothalamic arcuate nucleus. The expression of phosphorylated extracellular signal-regulated protein kinase 1/2 (pERK1/2), phosphorylated calcium/calmodulin-dependent protein kinase-IIalpha (pCaMK-IIalpha) protein and phosphorylated IkappaB (pIkappaB) protein was increased by s.c. formalin injection at various time points. We also found that increased pERK1/2, pCaMKIIalpha and pIkappaB protein after s.c. formalin injection was mainly located in the arcuate nucleus of hypothalamus in which cells containing beta-endorphin after s.c. formalin injection also express pERK1/2, pCaMK-IIalpha and pIkappaB immunoreactivity. In addition, formalin-induced POMC mRNA expression was significantly reduced by 10 min, pretreatment with i.c.v. PD98059 (mitogen-activated protein kinase (MAPK) pathways inhibitor; 6.6 mug) and KN93 (pCaMK-II inhibitor; 20 mug). In conclusion, POMC mRNA expression in the arcuate nucleus of the hypothalamus was increased by inflammatory pain stimuli, in which pERK1/2, pCaMK-IIalpha and NFkappaB may play an important role in the expression of the hypothalamic POMC gene and beta-endorphin expression.


Asunto(s)
Núcleo Arqueado del Hipotálamo/metabolismo , Regulación de la Expresión Génica/fisiología , Dolor/patología , Dolor/fisiopatología , Proopiomelanocortina/metabolismo , betaendorfina/metabolismo , Análisis de Varianza , Animales , Núcleo Arqueado del Hipotálamo/efectos de los fármacos , Quinasa de la Proteína Quinasa Dependiente de Calcio-Calmodulina/genética , Quinasa de la Proteína Quinasa Dependiente de Calcio-Calmodulina/metabolismo , Formaldehído , Regulación de la Expresión Génica/efectos de los fármacos , Proteínas I-kappa B/genética , Proteínas I-kappa B/metabolismo , Masculino , Ratones , Ratones Endogámicos ICR , Dolor/etiología , Proopiomelanocortina/genética , ARN Mensajero/metabolismo , Factores de Tiempo , betaendorfina/genética
11.
Neuroscience ; 142(4): 1281-92, 2006 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-16938401

RESUMEN

The effect of single or repeated restraint stress on several signal molecules in the hypothalamus was studied in ICR mice. Single restraint stress was induced for 30, 60, and 120 min. A repeated restraint stress was induced for 2 h daily during four consecutive days, and then induced in the same time course on the fifth day. In the immunoblot assay, we observed that the signal molecules c-Fos, phosphorylated extracellular cell-regulated protein kinase (pERK), phosphorylated calcium/calmodulin dependent protein kinase II (pCaMKII) and phosphorylated cyclic-AMP response element binding protein (pCREB) in the hypothalamus were increased by single restraint, and the increased c-Fos and pERK levels were attenuated by repeated restraint stress. However, pCaMKII and pCREB levels were increased by both single and repeated restraint stress. We also observed in the immunohistochemistry study that immunoreactivities (IR) of these signal molecules were changed in paraventricular (PVN) and arcuate nuclei (ArcN) of the hypothalamus in accordance with immunoblot results. Furthermore, in confocal immunofluorescence, the pCaMKII and pCREB up-regulated by repeated restraint stress were co-localized within many neurons of PVN and ArcN. In addition, we found that c-Fos and pCaMKII IR in locus coeruleus (LC) were increased by single restraint, and were attenuated by repeated restraint stress. However, the pERK and pCREB IR were increased by both single and repeated restraint stress. The confocal study revealed that pERK and pCREB up-regulated by repeated restraint stress were co-localized within many neurons of LC. Our results suggest that single and repeated restraint stress differentially triggers the induction and phosphorylation of several signal molecules in the PVN, ArcN, and LC. In addition, single and repeated stress stimuli elicited the brain-region specific changes of signal molecules examined. Furthermore, the upstream signal molecule activating CREB may be also brain-region specific, especially in repeated stress stimuli.


Asunto(s)
Núcleo Arqueado del Hipotálamo/metabolismo , Vías Autónomas/metabolismo , Locus Coeruleus/metabolismo , Núcleo Hipotalámico Paraventricular/metabolismo , Transducción de Señal/fisiología , Estrés Psicológico/metabolismo , Animales , Núcleo Arqueado del Hipotálamo/fisiopatología , Vías Autónomas/fisiopatología , Biomarcadores/metabolismo , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina , Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , Recuento de Células , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Modelos Animales de Enfermedad , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Locus Coeruleus/fisiopatología , Masculino , Ratones , Ratones Endogámicos ICR , Microscopía Confocal , Neuronas/metabolismo , Núcleo Hipotalámico Paraventricular/fisiopatología , Fosforilación , Proteínas Proto-Oncogénicas c-fos/metabolismo , Restricción Física , Estrés Psicológico/fisiopatología , Regulación hacia Arriba/fisiología
12.
Biotechnol Prog ; 18(3): 647-51, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12052086

RESUMEN

The baculovirus expression system has been used to produce large amounts of biologically active proteins by infecting insect cells with a recombinant baculovirus expressing the target protein. For an efficient expression of the target protein, it is necessary to infect insect cells with an adequate amount of virus. However, current methods are time-consuming and either have technical difficulties or are limited as a result of virus expression mechanism using a reporter gene. A novel method is developed to yield virus titers in 10 h that is easy to perform using 96-well plates and applicable to both any Autographa californica nucleopolyhyderovirus (AcNPV) and Bombyx mori nucleopolyhedrovirus (BmNPV)-based recombinant baculovirus. This assay uses an antibody to a DNA-binding protein to detect the infected cells via immunostaining. The titer is determined by counting foci produced as a result of infection of the virus under a fluorescent microscope. The required incubation period was shortened considerably because infected cells expressed viral antigens at the post-infection time of 4 h. Therefore, 10 h was enough to estimate the virus titer including virus infection time, insect cell culture, and estimation of virus titer. Titers determined using this immunological assay are comparable, both in value and validity, to those obtained using a traditional method, provided that the stocks have titers above 10(3) pfu/mL.


Asunto(s)
Anticuerpos Antivirales/análisis , Baculoviridae/aislamiento & purificación , Animales , Anticuerpos Antivirales/genética , Baculoviridae/inmunología , Línea Celular , Proteínas Fluorescentes Verdes , Proteínas Luminiscentes/genética , Reproducibilidad de los Resultados , Spodoptera
13.
Brain Res ; 884(1--2): 98-103, 2000 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-11082491

RESUMEN

Scrapie is a transmissible neurodegenerative disease of sheep and goats. The neuropathological changes include vacuolation, astrocytosis, the development of amyloid plaques in some instances, and neuronal loss. The mechanisms involved in neuronal cell death in scrapie are not known. Recently, we reported the presence of oxidative stress in the brains of scrapie-infected animals and suggested that this is the main mechanism that induces neuronal cell loss. It is known that oxidative stress induced by free radicals is associated with iron accumulation; this association led to an examination of the levels of iron (total iron, Fe(2+) and Fe(3+)) in the brains of control and scrapie-infected mice by biochemical methods. In the scrapie-infected group, both the level of total iron and the Fe(3+) level were significantly increased in cerebral cortex, striatum, and brainstem as compared to the values in the control group. A shift in the ratio of Fe(2+)/Fe(3+) was observed in the same regions of infected mice. Additionally, in this scrapie model, we confirmed the presence of oxidative stress, as evidenced by the increase of free malondialdehyde. These results suggest that iron metabolism is changed and that iron-induced oxidative stress partly contributes to neurodegeneration in scrapie infection.


Asunto(s)
Encéfalo/metabolismo , Compuestos Férricos/sangre , Compuestos Ferrosos/sangre , Hierro/sangre , Estrés Oxidativo/fisiología , Scrapie/metabolismo , Animales , Encéfalo/patología , Encéfalo/fisiopatología , Tronco Encefálico/citología , Tronco Encefálico/metabolismo , Corteza Cerebral/citología , Corteza Cerebral/metabolismo , Hipocampo/citología , Hipocampo/metabolismo , Peroxidación de Lípido/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Neostriado/citología , Neostriado/metabolismo , Neurotoxinas/metabolismo , Scrapie/patología , Scrapie/fisiopatología
14.
Mol Cells ; 10(4): 399-404, 2000 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-10987136

RESUMEN

Non-redundant expressed sequence tags (ESTs) were generated from six different organs at various developmental stages of Chinese cabbage, Brassica rapa L. ssp. pekinensis. Of the 1,295 ESTs, 915 (71%) showed significantly high homology in nucleotide or deduced amino acid sequences with other sequences deposited in databases, while 380 did not show similarity to any sequences. Briefly, 598 ESTs matched with proteins of identified biological function, 177 with hypothetical proteins or non-annotated Arabidopsis genome sequences, and 140 with other ESTs. About 82% of the top-scored matching sequences were from Arabidopsis or Brassica, but overall 558 (43%) ESTs matched with Arabidopsis ESTs at the nucleotide sequence level. This observation strongly supports the idea that gene-expression profiles of Chinese cabbage differ from that of Arabidopsis, despite their genome structures being similar to each other. Moreover, sequence analyses of 21 Brassica ESTs revealed that their primary structure is different from those of corresponding annotated sequences of Arabidopsis genes. Our data suggest that direct prediction of Brassica gene expression pattern based on the information from Arabidopsis genome research has some limitations. Thus, information obtained from the Brassica EST study is useful not only for understanding of unique developmental processes of the plant, but also for the study of Arabidopsis genome structure.


Asunto(s)
Brassica/genética , Etiquetas de Secuencia Expresada , Perfilación de la Expresión Génica , Genoma de Planta , Arabidopsis/genética , Bases de Datos como Asunto , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico
15.
Mol Biol Cell ; 11(4): 1433-43, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10749940

RESUMEN

The engagement of integrin alpha7 in E63 skeletal muscle cells by laminin or anti-alpha7 antibodies triggered transient elevations in the intracellular free Ca(2+) concentration that resulted from both inositol triphosphate-evoked Ca(2+) release from intracellular stores and extracellular Ca(2+) influx through voltage-gated, L-type Ca(2+) channels. The extracellular domain of integrin alpha7 was found to associate with both ectocalreticulin and dihydropyridine receptor on the cell surface. Calreticulin appears to also associate with cytoplasmic domain of integrin alpha7 in a manner highly dependent on the cytosolic Ca(2+) concentration. It appeared that intracellular Ca(2+) release was a prerequisite for Ca(2+) influx and that calreticulin associated with the integrin cytoplasmic domain mediated the coupling of between the Ca(2+) release and Ca(2+) influx. These findings suggest that calreticulin serves as a cytosolic activator of integrin and a signal transducer between integrins and Ca(2+) channels on the cell surface.


Asunto(s)
Antígenos CD/metabolismo , Señalización del Calcio/fisiología , Proteínas de Unión al Calcio/metabolismo , Calcio/metabolismo , Cadenas alfa de Integrinas , Ribonucleoproteínas/metabolismo , Animales , Anticuerpos/farmacología , Antígenos CD/inmunología , Proteínas de Unión al Calcio/inmunología , Calreticulina , Línea Celular , Citosol/metabolismo , Técnica del Anticuerpo Fluorescente , Fluorometría , Inositol 1,4,5-Trifosfato/metabolismo , Activación del Canal Iónico , Laminina/farmacología , Músculo Esquelético/citología , Músculo Esquelético/metabolismo , Ratas , Ribonucleoproteínas/inmunología , Transducción de Señal/fisiología
16.
Br J Radiol ; 73(865): 73-5, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10721324

RESUMEN

We report a case of pseudomembranous necrotizing bronchial aspergillosis in a patient with acute myelocytic leukaemia who died of massive haemoptysis. Lobar collapse was demonstrated on chest radiography. CT showed a marked necrotic thickening of the lobar bronchus with extension of the disease in to the peribronchial region.


Asunto(s)
Aspergilosis/diagnóstico por imagen , Leucemia Mieloide Aguda/complicaciones , Enfermedades Pulmonares Fúngicas/diagnóstico por imagen , Aspergilosis/complicaciones , Aspergilosis/patología , Resultado Fatal , Humanos , Enfermedades Pulmonares Fúngicas/complicaciones , Enfermedades Pulmonares Fúngicas/patología , Masculino , Persona de Mediana Edad , Necrosis , Tomografía Computarizada por Rayos X
17.
Life Sci ; 66(4): 317-26, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10665983

RESUMEN

We examined the effects of cigarette smoke (CS) on three parameters associated with kainic acid (KA)-induced neurotoxicity: seizure activity, cell loss in the hippocampus, and increased Fos-related antigen (FRA) expression. Animals were exposed to the main stream of CS from 15 Kentucky 2R1F research cigarettes containing 28.6 mg tar and 1.74 mg nicotine per cigarette, for 10 min a day, 6 days per week, for 4 weeks, using an automatic smoking machine. KA administration (10 mg/kg, i.p.) produced robust behavioral convulsions lasting 4-5 h. Pre-exposure to CS significantly reduced the seizures, mortality, and severe loss of cells in regions CA1 and CA3 of the hippocampus after KA administration. Consistently, pre-exposure to CS significantly attenuated the KA-induced increased FRA immunoreactivity in the hippocampus. In contrast, pretreatment with central nicotinic antagonist, mecamylamine (2 or 10 mg/kg, i.p.) blocked the neuroprotective effects mediated by CS in a dose-dependent manner. These results indicate that CS exposure provides neuroprotection against the KA insult via nicotinic receptor activation.


Asunto(s)
Encéfalo/efectos de los fármacos , Ácido Kaínico/toxicidad , Fármacos Neuroprotectores/farmacología , Nicotiana , Plantas Tóxicas , Humo , Animales , Sitios de Unión , Masculino , Mecamilamina/farmacología , Nicotina/farmacología , Proteínas Proto-Oncogénicas c-fos/análisis , Proteínas Proto-Oncogénicas c-fos/inmunología , Ratas , Ratas Sprague-Dawley , Receptores de N-Metil-D-Aspartato/fisiología , Receptores Nicotínicos/fisiología
18.
AJNR Am J Neuroradiol ; 20(9): 1744-6, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10543652

RESUMEN

We report a case of cemento-ossifying fibroma that presented as a large extraosseous mass in the masticator and parapharyngeal space. CT scanning and MR imaging showed a large extraosseous mass with central conglomerated, well-matured ossified nodules and fatty marrow. The central matured ossified nodules were of low density on CT scans and high signal intensity on T1- and T2-weighted MR images. Multiplanar reformatted CT scans revealed the origin of the mass to be at the extraction site of the right lower second molar tooth.


Asunto(s)
Fibroma Osificante/diagnóstico , Imagen por Resonancia Magnética , Neoplasias Mandibulares/diagnóstico , Tumores Odontogénicos/diagnóstico , Neoplasias Faríngeas/diagnóstico , Tomografía Computarizada por Rayos X , Diagnóstico Diferencial , Femenino , Fibroma Osificante/patología , Humanos , Neoplasias Mandibulares/patología , Persona de Mediana Edad , Diente Molar/patología , Tumores Odontogénicos/patología , Neoplasias Faríngeas/patología , Extracción Dental
19.
Biomaterials ; 18(23): 1565-9, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9430340

RESUMEN

A novel biodegradable polymer blend was developed for potential biomedical applications. A 50:50 poly(lactide-co-glycolide) (PLAGA) was blended in a 50:50 ratio with the followiing polyphosphazenes (PPHOS): poly[(25% ethyl glycinato)(75% p-methylphenoxy)phosphazene[, poly[(50% ethyl glycinato)(50% p-methylphenoxy)phosphazene], and poly[(75% ethyl glycinato)(25% p-methylphenoxy)phosphazene] to obtain Blends A, B, and C, respectively, using a mutual solvent technique. The miscibility of these blends was determined by measuring their glass transition temperature (Tg) using differential scanning calorimetry. After fabrication using a casting technique, the degradation of the matrices was examined. Differential scanning calorimetry showed one glass transition temperature for each blend which was between the Tg's of their respective parent polymers indicating miscibility of the blends. Surface analysis by scanning electron microscopy showed the matrices to have smooth uniform surfaces. Degradation studies showed near-zero order degradation kinetics for the blends with Blends A and B losing 10% of their mass after two weeks and Blend C degrading more rapidly (30% mass loss during the same period). These findings suggest that these novel biodegradable PLAGA/PPHOS blends may be useful for biomedical purposes.


Asunto(s)
Materiales Biocompatibles/química , Ácido Láctico/química , Compuestos Organofosforados/química , Ácido Poliglicólico/química , Polímeros/química , Materiales Biocompatibles/metabolismo , Ácido Láctico/metabolismo , Microscopía Electrónica de Rastreo , Ácido Poliglicólico/metabolismo , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Polímeros/metabolismo , Solventes/química , Propiedades de Superficie , Temperatura
20.
Biochem Biophys Res Commun ; 150(3): 904-8, 1988 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-2829898

RESUMEN

We report the isolation of a 1.5 kb cDNA clone for the beta subunit of human pyruvate dehydrogenase (E1) from a human liver lambda gt11 cDNA library using anti-E1 serum. We generated a peptide sequence of 24 amino acids starting from the N-terminus of bovine heart mature E1 beta. The identity of the E1 beta cDNA clone was confirmed by the similarity between the amino acid sequence deduced from the cDNA nucleotide sequence and the known amino acid sequence of bovine heart E1 beta. In Northern analysis of total RNA extracted from human heart, the E1 beta cDNA clone hybridized to a major 1.6 kb and a minor 5.2 kb RNA species.


Asunto(s)
ADN/aislamiento & purificación , Complejo Piruvato Deshidrogenasa/genética , Secuencia de Aminoácidos , Bacteriófago lambda/genética , Secuencia de Bases , ADN/genética , Enzimas de Restricción del ADN , ADN Recombinante/aislamiento & purificación , Humanos , Hígado/análisis , Datos de Secuencia Molecular , Hibridación de Ácido Nucleico
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