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1.
Clin Microbiol Infect ; 24(12): 1305-1310, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29496597

RESUMEN

OBJECTIVES: Antimicrobial resistance (AMR) is a priority for surveillance in bacterial infections. For leprosy, AMR has not been assessed because Mycobacterium leprae does not grow in vitro. We aim to obtain AMR data using molecular detection of resistance genes and to conduct a prospective open survey of resistance to antileprosy drugs in countries where leprosy is endemic through a WHO surveillance network. METHODS: From 2009 to 2015, multi-bacillary leprosy cases at sentinel sites of 19 countries were studied for resistance to rifampicin, dapsone and ofloxacin by PCR sequencing of the drug-resistance-determining regions of the genes rpoB, folP1 and gyrA. RESULTS: Among 1932 (1143 relapse and 789 new) cases studied, 154 (8.0%) M. leprae strains were found with mutations conferring resistance showing 182 resistance traits (74 for rifampicin, 87 for dapsone and 21 for ofloxacin). Twenty cases showed rifampicin and dapsone resistance, four showed ofloxacin and dapsone resistance, but no cases were resistant to rifampicin and ofloxacin. Rifampicin resistance was observed among relapse (58/1143, 5.1%) and new (16/789, 2.0%) cases in 12 countries. India, Brazil and Colombia reported more than five rifampicin-resistant cases. CONCLUSIONS: This is the first study reporting global data on AMR in leprosy. Rifampicin resistance emerged, stressing the need for expansion of surveillance. This is also a call for vigilance on the global use of antimicrobial agents, because ofloxacin resistance probably developed in relation to the general intake of antibiotics for other infections as it is not part of the multidrug combination used to treat leprosy.


Asunto(s)
Antibacterianos/uso terapéutico , Farmacorresistencia Bacteriana/genética , Lepra/epidemiología , Mycobacterium leprae/efectos de los fármacos , Mycobacterium leprae/genética , Antibacterianos/efectos adversos , Proteínas Bacterianas/genética , Biopsia con Aguja , Brasil/epidemiología , Colombia/epidemiología , Girasa de ADN/genética , Dapsona/uso terapéutico , Enfermedades Endémicas/estadística & datos numéricos , Monitoreo Epidemiológico , Salud Global , Humanos , India/epidemiología , Lepra/diagnóstico , Lepra/tratamiento farmacológico , Lepra/microbiología , Pruebas de Sensibilidad Microbiana , Mutación , Ofloxacino/uso terapéutico , Reacción en Cadena de la Polimerasa , Estudios Prospectivos , Recurrencia , Rifampin/uso terapéutico , Vigilancia de Guardia , Piel/microbiología , Piel/patología , Encuestas y Cuestionarios , Organización Mundial de la Salud
2.
J Nutr Health Aging ; 19(7): 719-28, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26193854

RESUMEN

BACKGROUND/OBJECTIVES: Serum polyunsaturated fatty acid (PUFA) composition reflects dietary intake and is related to risks for cardiovascular diseases. We hypothesized that serum n-3 PUFA composition, especially including long-chain n-3 PUFA such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), is associated with inflammatory status, which is related to increased risk for cardiovascular diseases. SUBJECTS/METHODS: We investigated the relationship between serum PUFA composition and high-sensitivity C-reactive protein (hs-CRP) levels in a cross-sectional study among 1,102 healthy men and women aged 40-74 years who reside in Kobe City. Multiple linear regression models that predict hs-CRP level were prepared to confirm the contribution of serum total n-3 PUFA, long-chain n-3 PUFA, EPA and DHA compositions after adjusting for other PUFAs and atherosclerotic risk factors. RESULTS: The serum n-3 PUFA, particularly long-chain n-3 PUFA, compositions were inversely associated with the hs-CRP levels. The standardized regression coefficient was -0.089 (p < 0.01) for total n-3 PUFA, -0.091 (p < 0.01) for long-chain n-3 PUFA, -0.071 (p = 0.03) for EPA, and -0.068 (p = 0.04) for DHA. The n-6 PUFA compositions were also inversely associated with the hs-CRP levels (-0.169 [p < 0.01] for total n-6 PUFA and -0.159 [p < 0.01] for linoleic acid). CONCLUSIONS: The serum n-3 PUFA compositions were inversely related with the hs-CRP levels, similar associations were also observed in n-6 PUFA compositions. Our results suggest that dietary PUFA intake was inversely associated with attenuated inflammation in healthy Japanese population.


Asunto(s)
Pueblo Asiatico , Proteína C-Reactiva/análisis , Ácidos Grasos Omega-3/sangre , Ácidos Grasos Omega-6/sangre , Salud , Adulto , Anciano , Enfermedades Cardiovasculares/sangre , Ciudades , Estudios Transversales , Dieta , Ácidos Docosahexaenoicos/sangre , Ácido Eicosapentaenoico/sangre , Ácidos Grasos Omega-3/química , Femenino , Encuestas Epidemiológicas , Humanos , Inflamación/sangre , Japón , Masculino , Persona de Mediana Edad , Factores de Riesgo
3.
Methods Find Exp Clin Pharmacol ; 32(10): 745-8, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21225011

RESUMEN

Administration of antihistamines 2-4 weeks before the pollen season showed a greater inhibitory effect on nasal allergy symptoms in patients with seasonal allergic rhinitis. However, the mechanism of slow-onset effects of preseasonal treatment with antihistamines remains unclear. Here, we investigated the effect of preseasonal prophylactic treatment with antihistamines on nasal symptoms and the expression of histamine H1 receptor (H1R) mRNA of the nasal mucosa in patients with cedar pollen pollinosis. During the peak pollen period, the expression of H1R mRNA in the nasal mucosa and the scores of sneezing and watery rhinorrhea in patients receiving preseasonal prophylactic treatment with antihistamines were significantly suppressed in comparison with those in the patients without treatment. Moreover, there was a significant correlation between the nasal symptoms and the expression of H1R mRNA in both patients with or without preseasonal prophylactic treatment. These findings suggest that preseasonal prophylactic treatment with antihistamines is more effective than on-seasonal administration to patients with pollinosis in reducing nasal symptoms during the peak pollen period by suppressing H1R gene expression in the nasal mucosa.


Asunto(s)
Antagonistas de los Receptores Histamínicos/farmacología , Mucosa Nasal/efectos de los fármacos , Receptores Histamínicos H1/efectos de los fármacos , Rinitis Alérgica Estacional/prevención & control , Cryptomeria/inmunología , Femenino , Estudios de Seguimiento , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Mucosa Nasal/inmunología , Polen/inmunología , ARN Mensajero/metabolismo , Receptores Histamínicos H1/genética , Rinitis Alérgica Estacional/inmunología
4.
J Neurosci ; 21(2): 750-7, 2001 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-11160454

RESUMEN

NMDA receptors, an ionotropic subtype of glutamate receptors (GluRs) forming high Ca(2+)-permeable cation channels, are composed by assembly of the GluRzeta subunit (NR1) with any one of four GluRepsilon subunits (GluRepsilon1-4; NR2A-D). In the present study, we investigated neuronal functions in mice lacking the GluRepsilon1 subunit. GluRepsilon1 mutant mice exhibited a malfunction of NMDA receptors, as evidenced by alterations of [(3)H]MK-801 binding as well as (45)Ca(2+) uptake through the NMDA receptors. A postmortem brain analysis revealed that both dopamine and serotonin metabolism were increased in the frontal cortex and striatum of GluRepsilon1 mutant mice. The NMDA-stimulated [(3)H]dopamine release from the striatum was increased, whereas [(3)H]GABA release was markedly diminished in GluRepsilon1 mutant mice. When (+)bicuculline, a GABA(A) receptor antagonist, was added to the superfusion buffer, NMDA-stimulated [(3)H]dopamine release was significantly increased in wild-type, but not in the mutant mice. GluRepsilon1 mutant mice exhibited an increased spontaneous locomotor activity in a novel environment and an impairment of latent learning in a water-finding task. Hyperlocomotion in GluRepsilon1 mutant mice was attenuated by treatment with haloperidol and risperidone, both of which are clinically used antipsychotic drugs, at doses that had no effect in wild-type mice. These findings provide evidence that NMDA receptors are involved in the regulation of behavior through the modulation of dopaminergic and serotonergic neuronal systems. In addition, our findings suggest that GluRepsilon1 mutant mice are useful as an animal model of psychosis that is associated with NMDA receptor malfunction and hyperfunction of dopaminergic and serotonergic neuronal systems.


Asunto(s)
Dopamina/metabolismo , Enfermedades del Sistema Nervioso/metabolismo , Subunidades de Proteína , Receptores de N-Metil-D-Aspartato/metabolismo , Serotonina/metabolismo , Animales , Antipsicóticos/farmacología , Monoaminas Biogénicas/metabolismo , Calcio/metabolismo , Calcio/farmacocinética , Cuerpo Estriado/efectos de los fármacos , Cuerpo Estriado/metabolismo , Maleato de Dizocilpina/metabolismo , Antagonistas de Aminoácidos Excitadores/metabolismo , Lóbulo Frontal/efectos de los fármacos , Lóbulo Frontal/metabolismo , Antagonistas del GABA/farmacología , Hipocampo/metabolismo , Aprendizaje/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Ratones Mutantes , Actividad Motora/efectos de los fármacos , Actividad Motora/genética , N-Metilaspartato/metabolismo , N-Metilaspartato/farmacología , Enfermedades del Sistema Nervioso/genética , Enfermedades del Sistema Nervioso/patología , Neuronas/metabolismo , Receptores de N-Metil-D-Aspartato/deficiencia , Receptores de N-Metil-D-Aspartato/genética , Tálamo/metabolismo , Ácido gamma-Aminobutírico/metabolismo
5.
J Agric Food Chem ; 48(11): 5618-23, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11087528

RESUMEN

Intestinal glucose uptake is mainly performed by the sodium-dependent glucose transporter, SGLT1. The transport activity of SGLT1 was markedly inhibited by green tea polyphenols, this inhibitory activity being most pronounced in polyphenols having galloyl residues such as epicatechin gallate (ECg) and epigallocatechin gallate (EGCg). Experiments using brush-border membrane vesicles obtained from the rabbit small intestine demonstrated that ECg inhibited SGLT1 in a competitive manner, although ECg itself was not transported via SGLT1. The present results suggest that tea polyphenols such as ECg interact with SGLT1 as antagonist-like molecules, possibly playing a role in controlling the dietary glucose uptake in the intestinal tract.


Asunto(s)
Mucosa Intestinal/fisiología , Proteínas de Transporte de Monosacáridos/antagonistas & inhibidores , Fenoles/química , Fenoles/farmacología , Polímeros/química , Polímeros/farmacología , Té/química , Animales , Transporte Biológico/efectos de los fármacos , Catequina/análogos & derivados , Catequina/química , Catequina/farmacología , Flavonoides/química , Flavonoides/farmacología , Glucosa/metabolismo , Técnicas In Vitro , Mucosa Intestinal/efectos de los fármacos , Yeyuno , Cinética , Masculino , Microvellosidades/efectos de los fármacos , Microvellosidades/fisiología , Fenoles/aislamiento & purificación , Polímeros/aislamiento & purificación , Conejos , Ratas , Ratas Wistar
6.
Biosci Biotechnol Biochem ; 64(6): 1166-72, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10923786

RESUMEN

An ethanol extract from sesame seeds inhibited the taurine uptake in human intestinal epithelial Caco-2 cells. The uptake of such alpha-amino acids as leucine and glutamic acid was not inhibited by the extract, indicating that this inhibition is specific to the taurine uptake. The unknown inhibitor in the sesame extract was purifled by reversed-phase HPLC by monitoring the inhibitory effect on taurine uptake. The isolated substance was identified as lysophosphatidylcholine, linoleoyl (Lyso-PC), by NMR and MS analysis. Lyso-PC inhibited the taurine uptake in a dose-dependent manner with an IC50 value of approximately 200 microM. Although Lyso-PC is known to be a surface active and cell lytic compound, neither damage nor loss of integrity of the Caco2 cell monolayer was apparent after treating with 200 microM Lyso-PC. Inhibition was observed by incubating cells with Lyso-PC for only 1 min prior to the uptake experiments. These results suggest the direct effect of Lyso-PC on the cell membrane to be the main mechanism for this inhibition. Lyso-PC may play a role in the regulation of certain intestinal transporters.


Asunto(s)
Semillas/química , Taurina/metabolismo , Transporte Biológico Activo/efectos de los fármacos , Células CACO-2 , Análisis de los Alimentos , Humanos , Mucosa Intestinal/metabolismo , Intestinos/efectos de los fármacos , Cinética , Lisofosfatidilcolinas/aislamiento & purificación , Lisofosfatidilcolinas/farmacología , Lisofosfatidilcolinas/toxicidad , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología
7.
Infect Immun ; 68(8): 4378-83, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10899833

RESUMEN

Helicobacter pylori can produce a persistent infection in the human stomach, where chronic and active inflammation, including the infiltration of phagocytes such as neutrophils and monocytes, is induced. H. pylori may have a defense system against the antimicrobial actions of phagocytes. We studied the defense mechanism of H. pylori against host-derived peroxynitrite (ONOO(-)), a bactericidal metabolite of nitric oxide, focusing on the role of H. pylori urease, which produces CO(2) and NH(3) from urea and is known to be an essential factor for colonization. The viability of H. pylori decreased in a time-dependent manner with continuous exposure to 1 microM ONOO(-), i.e., 0.2% of the initial bacteria remained after a 5-min treatment without urea. The bactericidal action of ONOO(-) against H. pylori was significantly attenuated by the addition of 10 mM urea, the substrate for urease, whereas ONOO(-)-induced killing of a urease-deficient mutant of H. pylori or Campylobacter jejuni, another microaerophilic bacterium lacking urease, was not affected by the addition of urea. Such a protective effect of urea was potentiated by supplementation with exogenous urease, and it was almost completely nullified by 10 microM flurofamide, a specific inhibitor of urease. The bactericidal action of ONOO(-) was also suppressed by the addition of 20 mM NaHCO(3) but not by the addition of 20 mM NH(3). In addition, the nitration of L-tyrosine of H. pylori after treatment with ONOO(-) was significantly reduced by the addition of urea or NaHCO(3), as assessed by high-performance liquid chromatography with electrochemical detection. These results suggest that H. pylori-associated urease functions to produce a potent ONOO(-) scavenger, CO(2)/HCO(3)(-), that defends the bacteria from ONOO(-) cytotoxicity. The protective effect of urease may thus facilitate sustained bacterial colonization in the infected gastric mucosa.


Asunto(s)
Helicobacter pylori/efectos de los fármacos , Nitratos/farmacología , Ureasa/metabolismo , Amoníaco/farmacología , Antibacterianos/farmacología , Dióxido de Carbono/metabolismo , Interacciones Farmacológicas , Helicobacter pylori/enzimología , Helicobacter pylori/patogenicidad , Pruebas de Sensibilidad Microbiana , Oxidantes/farmacología , Bicarbonato de Sodio/farmacología , Tirosina/análogos & derivados , Tirosina/metabolismo , Urea/metabolismo , Ureasa/antagonistas & inhibidores
8.
J Neurosci ; 20(6): 2418-26, 2000 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-10704516

RESUMEN

Tyrosine hydroxylase (TH) is the initial and rate-limiting enzyme for the biosynthesis of catecholamines that are considered to be involved in a variety of neuropsychiatric functions. Here, we report behavioral and neuropsychological deficits in mice carrying a single mutated allele of the TH gene in which TH activity in tissues is reduced to approximately 40% of the wild-type activity. In the mice heterozygous for the TH mutation, noradrenaline accumulation in brain regions was moderately decreased to 73-80% of the wild-type value. Measurement of extracellular noradrenaline level in the frontal cortex by the microdialysis technique showed a reduction in high K(+)-evoked noradrenaline release in the mutants. The mutant mice displayed impairment in the water-finding task associated with latent learning performance. They also exhibited mild impairment in long-term memory formation in three distinct forms of associative learning, including active avoidance, cued fear conditioning, and conditioned taste aversion. These deficits were restored by the drug-induced stimulation of noradrenergic activity. In contrast, the spatial learning and hippocampal long-term potentiation were normal in the mutants. These results provide genetic evidence that the central noradrenaline system plays an important role in memory formation, particularly in the long-term memory of conditioned learning.


Asunto(s)
Hipocampo/fisiología , Norepinefrina/metabolismo , Tirosina 3-Monooxigenasa/genética , Animales , Aprendizaje por Asociación/fisiología , Reacción de Prevención/fisiología , Química Encefálica/genética , Quimera , Miedo , Femenino , Lóbulo Frontal/citología , Lóbulo Frontal/enzimología , Heterocigoto , Hipocampo/citología , Potenciación a Largo Plazo/fisiología , Masculino , Memoria/fisiología , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos ICR , Ratones Mutantes Neurológicos , Microdiálisis , Neuronas/enzimología , Percepción Espacial/fisiología , Tirosina 3-Monooxigenasa/metabolismo
9.
Yakugaku Zasshi ; 120(3): 311-4, 2000 Mar.
Artículo en Japonés | MEDLINE | ID: mdl-10723275

RESUMEN

While copper(II) gluconate (CuGL) is generally used as a nutrient supplement for infant foods and as an oral deodorant, little information is available regarding a toxic effect of CuGL on mammals. In this article, we examined in vivo induction of toxicity and change of level of glutathione and ascorbic acid, major biological antioxidants, lipid peroxide and copper (Cu) in liver and kidney 4 h after single intraperitoneal administration of CuGL at 0.05 and 0.10 mmol/kg to mice. Serum glutamic pyruvic transaminase (SGPT) activity, an indicator of hepatotoxicity, significantly increased compared to control in proportion to doses of CuGL. Hepatic level of glutathione measured as nonprotein sulfhydryl was not proportional to CuGL doses, but enhanced after dosing of 0.05 mmol/kg and lowered by 0.10 mmol/kg. Like SGPT activity, serum urea nitrogen (SUN) concentration, an indicator of nephrotoxicity, significantly increased in proportion to doses of CuGL. Renal glutathione level was not different from control after dosing of 0.05 mmol/kg and lowered by 0.10 mmol/kg. In both organs, relative organ weight and lipid peroxide level were not affected by the treatment with CuGL; ascorbic acid level was elevated after dosing of 0.05 mmol/kg and was not different from control after treatment with 0.10 mmol/kg; like SGPT activity and SUN concentration, Cu level significantly increased in proportion to doses of CuGL. These results suggest that in the liver and kidney after the treatment with CuGL Cu accumulated may induce toxicity, leading to level changes of glutathione and ascorbic acid and to no induction of oxidative damage.


Asunto(s)
Ácido Ascórbico/metabolismo , Cobre/metabolismo , Desodorantes/toxicidad , Suplementos Dietéticos/toxicidad , Gluconatos/toxicidad , Glutatión/metabolismo , Riñón/efectos de los fármacos , Hígado/efectos de los fármacos , Animales , Gluconatos/administración & dosificación , Inyecciones Intraperitoneales , Riñón/metabolismo , Peróxidos Lipídicos/metabolismo , Hígado/metabolismo , Masculino , Ratones
10.
Biofactors ; 13(1-4): 61-5, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11237201

RESUMEN

Intestinal glucose uptake is mainly performed by its specific transporters, such as SGLT 1, GLUT 2 and 5 expressed in the intestinal epithelial cells. By using human intestinal epithelial Caco-2 cells we observed that intestinal glucose uptake was markedly inhibited by tea extracts. While several substances in green tea seem to be involved in this inhibition, catechins play the major role and epicatechin gallate (ECg) showed the highest inhibitory activity. Since our Caco-2 cells did not express enough amount of SGLT 1, the most abundant intestinal glucose transporter, the effect of ECg on SGLT 1 was evaluated by using brush border membrane vesicles obtained from the rabbit small intestine. ECg inhibited SGLT 1 in a competitive manner, although ECg itself was not transported via the glucose transporters. These results suggest that tea catechins could play a role in controlling the dietary glucose uptake at the intestinal tract and possibly contribute to blood glucose homeostasis.


Asunto(s)
Catequina/farmacología , Glucosa/metabolismo , Mucosa Intestinal/fisiología , Microvellosidades/metabolismo , , Animales , Transporte Biológico/efectos de los fármacos , Alimentos , Humanos , Absorción Intestinal/efectos de los fármacos , Mucosa Intestinal/efectos de los fármacos , Intestino Delgado , Microvellosidades/efectos de los fármacos , Conejos , Células Tumorales Cultivadas
11.
J Gastroenterol ; 34(1): 75-82, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10204614

RESUMEN

Decreased effective circulating blood volume is an important factor in ascites formation in liver cirrhosis. We designed a "body compression" apparatus as a means to restore effective blood volume and investigated its effectiveness in reducing ascites formation in cirrhotics in terms of its effect on parameters of ascites formation noted below. The subjects, eight cirrhotics with ascites and eight cirrhotics without ascites were given spironolactone (50-75 mg/day) and furosemide (40-80 mg/day) while they received a diet containing 85 mEq of sodium per day. All four limbs and the lower abdomen were compressed with constant pressure [height (cm) divided by 13.6 mmHg] once, for 3h, using stroke rehabilitation splints, while patients lay supine. In cirrhotics both with and without ascites, urine volume, urinary sodium excretion, and creatinine clearance during the body compression were greater than values during control (non-compression) periods (urine volume, means 285 vs 169 ml/3h; P < 0.001, urinary sodium excretion 15.8 vs 9.5 mEq/3h; p < 0.001, creatinine clearance 74 vs 59 ml/min, P < 0.001, respectively). The increased basal plasma renin activity, angiotensin II, aldosterone, and norepinephrine levels in all cirrhotics were significantly decreased by the body compression. In another group of six cirrhotics who received no diuretics or albumin, repeat body compression alleviated ascites in three with well preserved renal function, but was ineffective in three with markedly impaired renal function. These results suggest that the improvement in renal function brought about by the body compression is attributable to an increase in effective circulating blood volume. This maneuver may be a useful complementary therapy in patients with cirrhotic ascites with well preserved renal function.


Asunto(s)
Ascitis/prevención & control , Trajes Gravitatorios , Cirrosis Hepática/complicaciones , Adulto , Anciano , Ascitis/etiología , Ascitis/fisiopatología , Volumen Sanguíneo , Femenino , Transferencias de Fluidos Corporales , Estudios de Seguimiento , Humanos , Pruebas de Función Renal , Cirrosis Hepática/fisiopatología , Cirrosis Hepática/terapia , Pruebas de Función Hepática , Masculino , Persona de Mediana Edad , Presión , Resultado del Tratamiento
12.
Proc Natl Acad Sci U S A ; 95(11): 6097-102, 1998 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-9600923

RESUMEN

In mammals the retina contains photoactive molecules responsible for both vision and circadian photoresponse systems. Opsins, which are located in rods and cones, are the pigments for vision but it is not known whether they play a role in circadian regulation. A subset of retinal ganglion cells with direct projections to the suprachiasmatic nucleus (SCN) are at the origin of the retinohypothalamic tract that transmits the light signal to the master circadian clock in the SCN. However, the ganglion cells are not known to contain rhodopsin or other opsins that may function as photoreceptors. We have found that the two blue-light photoreceptors, cryptochromes 1 and 2 (CRY1 and CRY2), recently discovered in mammals are specifically expressed in the ganglion cell and inner nuclear layers of the mouse retina. In addition, CRY1 is expressed at high level in the SCN and oscillates in this tissue in a circadian manner. These data, in conjunction with the established role of CRY2 in photoperiodism in plants, lead us to propose that mammals have a vitamin A-based photopigment (opsin) for vision and a vitamin B2-based pigment (cryptochrome) for entrainment of the circadian clock.


Asunto(s)
Ritmo Circadiano/fisiología , Proteínas de Drosophila , Proteínas del Ojo , Flavoproteínas/fisiología , Hipotálamo/fisiología , Células Fotorreceptoras de Invertebrados , Proteínas de Plantas/fisiología , Retina/fisiología , Riboflavina/fisiología , Animales , Criptocromos , Ratones , Receptores Acoplados a Proteínas G , Opsinas de Bastones/fisiología
13.
J Biol Chem ; 272(22): 14115-9, 1997 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-9162038

RESUMEN

The sequential oxidation and cleavage of the side chain of 1alpha, 25-dihydroxyvitamin D3 (1alpha,25(OH)2D3) initiated by the hydroxylation at C-24 is considered to be the major pathway of this hormone in the target cell metabolism. In this study, we examined renal metabolism of a synthetic analog of 1alpha,25(OH)2D3, 24, 24-difluoro-1alpha,25-dihydroxyvitamin D3 (F2-1alpha,25(OH)2D3), C-24 of which was designed to resist metabolic hydroxylation. When kidney homogenates prepared from 1alpha,25(OH)2D3-supplemented rats were incubated with F2-1alpha,25(OH)2D3, it was mainly converted to a more polar metabolite. We isolated and unequivocally identified the metabolite as 24,24-difluoro-1alpha,25,26-trihydroxyvitamin D3 (F2-1alpha,25,26(OH)3D3) by ultraviolet absorption spectrometry, frit-fast atom bombardment liquid chromatography/mass spectroscopy analysis, and direct comparison with chemically synthesized F2-1alpha,25,26(OH)3D3. Metabolism of F2-1alpha,25(OH)2D3 into F2-1alpha,25,26(OH)3D3 by kidney homogenates was induced by the prior administration of 1alpha,25(OH)2D3 into rats. The C-24 oxidation of 1alpha,25(OH)2D3 in renal homogenates was inhibited by F2-1alpha,25(OH)2D3 in a concentration-dependent manner. Moreover, F2-1alpha,25,26(OH)3D3 was formed in ROS17/2.8 cells transfected with a plasmid expressing 1alpha,25(OH)2D3-24-hydroxylase (CYP24) but not in the cells transfected with that expressing vitamin D3-25-hydroxylase (CYP27) or containing inverted CYP27 cDNA. These results show that CYP24 catalyzes not only hydroxylation at C-24 and C-23 of 1alpha,25(OH)2D3 but also at C-26 of F2-1alpha,25(OH)2D3, indicating that this enzyme has a broader substrate specificity of the hydroxylation sites than previously considered.


Asunto(s)
Calcifediol/análogos & derivados , Calcitriol/análogos & derivados , Sistema Enzimático del Citocromo P-450/metabolismo , Riñón/metabolismo , Esteroide Hidroxilasas/metabolismo , Animales , Calcifediol/metabolismo , Calcitriol/metabolismo , Carbono/metabolismo , Hidrólisis , Ratas , Vitamina D3 24-Hidroxilasa
14.
Curr Eye Res ; 15(3): 345-9, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8654117

RESUMEN

Reverse transcription-polymerase chain reaction (RT-PCR) was performed to amplify a cDNA encoding a taurine transporter in the human retinal pigment epithelium (HRPE). The coding region of a PCR product was found to be 1863 bp long, predicting a 620-amino acid protein (69,826 Da). This cDNA sequence is almost identical to those taurine transporters recently determined in the human thyroid and placenta: 12 and 1 base pair(s) different from the reported thyroid and placenta transporter clones, respectively. The injection of mRNA in vitro transcribed from the PCR product markedly increased taurine uptake in Xenopus laevis oocytes. Taurine uptake is Na+ and Cl- dependent. Unlabeled taurine, beta-alanine and gamma-amino-n-butyric acid at 100 microM inhibited the uptake of radiolabeled taurine whereas 100 microM alpha-alanine and alpha-aminoisobutyric acid did not. A kinetic study showed that taurine uptake is mediated by a single carrier system with the apparent Michaelis-Menten constant of approximately 2 microM. These results suggest that the PCR product encodes a functional taurine transporter whose characteristics are similar to those of taurine uptake observed in the original HRPE cells. A DNA encoding the reported placental transporter was made from the PCR product by site-directed mutagenesis but it was not functional in the oocyte expression. A similar RT-PCR was performed with poly (A)+ mRNA isolated from JAR human placenta choriocarcinoma cells. This PCR product was identical to that from the HRPE. In addition, the clone of the human thyroid transporter was obtained and re-sequenced. Its translation coding region was also identical to that of the PCR product from the HRPE, showing that taurine transporters are identical in the human RPE, thyroid and placenta.


Asunto(s)
Proteínas Portadoras/genética , ADN Complementario/aislamiento & purificación , Glicoproteínas de Membrana/genética , Proteínas de Transporte de Membrana , Epitelio Pigmentado Ocular/química , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Transporte Biológico , Proteínas Portadoras/metabolismo , Coriocarcinoma/metabolismo , ADN Complementario/genética , Femenino , Expresión Génica , Humanos , Glicoproteínas de Membrana/metabolismo , Datos de Secuencia Molecular , Oocitos/metabolismo , Placenta/química , Reacción en Cadena de la Polimerasa , ARN Mensajero/genética , ARN Mensajero/aislamiento & purificación , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Taurina/metabolismo , Glándula Tiroides/química , Transcripción Genética , Neoplasias Uterinas/metabolismo , Xenopus laevis
15.
Invest Radiol ; 30(9): 538-43, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8537211

RESUMEN

RATIONALE AND OBJECTIVES: The authors compared the safety and pharmacokinetics of Iotrolan (water-soluble) in hysterosalpingography (HSG) with those of Lipiodol (oil-soluble). METHODS: Iotrolan and Lipiodol were administered intraperitoneally at doses of 100 mg iodine/kg to female rabbits. Retention in the body was investigated by x-ray imaging, plasma kinetics, and urinary and fecal excretion. Irritability in the abdomen was investigated by histologic examination. RESULTS: Iotrolan was entirely excreted into the urine within 2 days after administration. Conversely, Lipiodol was excreted into the urine, had a half-life of 50 days, and was retained for more than 21 days in the abdomen. Iotrolan induced no inflammatory reaction in the abdomen, whereas Lipiodol induced a marked abdominal inflammatory reaction, including granuloma formation. Iotrolan had no effect on iodine concentration in the thyroid; Lipiodol increased iodine concentration significantly. CONCLUSIONS: Iotrolan, which is a water-soluble and nonionic dimeric contrast medium, has potential greater safety for use in HSG than Lipiodol.


Asunto(s)
Medios de Contraste/farmacocinética , Histerosalpingografía , Aceite Yodado/farmacocinética , Ácidos Triyodobenzoicos/farmacocinética , Abdomen/patología , Animales , Líquido Ascítico/inducido químicamente , Líquido Ascítico/patología , Heces/química , Femenino , Granuloma/inducido químicamente , Semivida , Inyecciones Intraperitoneales , Yodo/análisis , Aceite Yodado/efectos adversos , Aceite Yodado/análisis , Irritantes/efectos adversos , Conejos , Radiografía Abdominal , Seguridad , Glándula Tiroides/efectos de los fármacos , Glándula Tiroides/metabolismo , Ácidos Triyodobenzoicos/efectos adversos , Ácidos Triyodobenzoicos/análisis , Ácidos Triyodobenzoicos/sangre , Ácidos Triyodobenzoicos/orina
16.
Jpn J Pharmacol ; 66(3): 337-45, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7869621

RESUMEN

The effects of a mixture of three peptidase inhibitors (PIs), amastatin, captopril and phosphoramidon, on methionine-enkephalin (Met-enk)-, beta-endorphin (beta-end)-, dynorphin-(1-13) (Dyn)- and electroacupuncture (EA)-induced antinociception were compared in rats. EA was performed by passing electric pulses (3 Hz, 0.1-msec duration, for 45 min) through acupuncture needles inserted into the Hoku-point. The antinociceptive effect was estimated by the hind paw pressure test. The antinociceptive effects of Met-enk and beta-end injected i.c.v. or i.t. and of Dyn injected i.t. were clearly potentiated by the PIs pretreated by the same administration routes as used for the injection of opioid peptides. The antinociceptive effects of Met-enk, beta-end and Dyn injected i.c.v. were also potentiated significantly by i.t.-PIs. PIs injected into the periaqueductal gray (PAG) potentiated EA antinociception. However, the EA effect was not affected by i.t.-PIs and was rather attenuated by i.c.v.-PIs. These results suggest that: i) Met-enk hydrolyzing enzymes are involved in the degradation of not only Met-enk but also beta-end and Dyn in the rat central nervous system; ii) Met-enk and beta-end act on both supraspinal and spinal sites, while Dyn acts only on the spinal site; iii) EA antinociception is mediated by supraspinal Met-enk and/or beta-end; and iv) an anti-opiate peptide system may be activated by EA stimulation, being susceptible to Met-enk hydrolyzing enzymes.


Asunto(s)
Analgesia , Electroacupuntura , Inhibidores de Proteasas/farmacología , Analgesia por Acupuntura , Animales , Combinación de Medicamentos , Dinorfinas/farmacología , Encefalina Metionina/farmacología , Masculino , Ratas , Ratas Sprague-Dawley , betaendorfina/farmacología
17.
Biochim Biophys Acta ; 1218(3): 297-307, 1994 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-8049255

RESUMEN

A cDNA encoding a pituitary adenylate cyclase-activating polypeptide (PACAP) receptor was cloned from a bovine brain cDNA library using a synthetic oligonucleotide probe corresponding to the partial N-terminal amino acid sequence of the PACAP receptor purified from the bovine brain. The cloned cDNA encoded a polypeptide of 513 amino acid residues with seven putative transmembrane domains. The deduced amino acid sequence exactly matched the N-terminal amino acid sequence of the purified PACAP receptor. It also shared an apparent similarity with the vasoactive intestinal peptide (VIP), secretin, growth hormone releasing hormone, calcitonin, and glucagon receptors, suggesting that the PACAP receptor is a member of the secretin receptor subfamily of the guanine nucleotide-binding regulatory protein-coupled receptor family. Northern blot analysis showed that the size of the major mRNA band which hybridized with the cDNA was about 7 kb in the bovine cerebral-cortex and hippocampus. An expression vector containing the cloned cDNA for the PACAP receptor was introduced into Chinese hamster ovary (CHO) cells. The affinity of PACAP receptors expressed on the transfected CHO cells was quite similar to that of natural PACAP receptors on the bovine brain membranes. Competitive binding experiments showed that PACAP38 displaced the binding of 125I-labeled PACAP27 to the receptors on the CHO cells more efficiently than PACAP27, while VIP was less effective. In addition, both of PACAP27 and PACAP38 elevated the levels of cAMP and inositol phosphates in the transformed CHO cells. These results indicate that the PACAP receptors encoded by the cloned cDNA are identical to the purified PACAP receptors, and that they can stimulate dual signaling cascades.


Asunto(s)
ADN Complementario/metabolismo , Neuropéptidos/metabolismo , Hipófisis/metabolismo , Receptores de la Hormona Hipofisaria/biosíntesis , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Células CHO , Bovinos , Clonación Molecular , Cricetinae , AMP Cíclico/metabolismo , Biblioteca de Genes , Fosfatos de Inositol/metabolismo , Cinética , Datos de Secuencia Molecular , Sondas de Oligonucleótidos , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa , Receptores del Polipéptido Activador de la Adenilato-Ciclasa Hipofisaria , Receptores de la Hormona Hipofisaria/metabolismo , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/metabolismo , Mapeo Restrictivo , Transfección
18.
Rinsho Ketsueki ; 33(9): 1151-7, 1992 Sep.
Artículo en Japonés | MEDLINE | ID: mdl-1433935

RESUMEN

Serum erythropoietin (Epo) levels were measured in 53 patients with multiple myeloma (MM), 49 normal subjects and 53 patients with some hematological diseases including aplastic anemia (AA), iron deficiency anemia, etc. to study the significance of erythropoietin in anemia of MM. The serum Epo level was 72.0 +/- 94.4 mIU/ml (mean +/- SD) in MM patients, which was significantly higher than in normal subjects (24.1 +/- 6.1 mIU/ml), but lower than in AA patients (7069.9 +/- 9406 mIU/ml). A significant inverse correlation was found between the hemoglobin (Hb) levels and the logarithmic values of serum Epo levels (r = -0.543, p < 0.05) in MM patients. This inverse correlation was stronger (r = -0.636, p < 0.05) in MM patients without renal dysfunction than in whole MM patients, while no correlation was observed in MM patients with renal dysfunction. These results indicate that MM patients with renal dysfunction have a low ability to synthesize Epo and that the supplemental therapy of recombinant Epo is effective to improve their anemia. In addition, the circadian rhythm of serum Epo level was lower in the morning than in the afternoon in both MM patients and normal controls. Serum Epo levels after chemotherapy in MM patients were elevated temporarily and then decreased in spite of no change of blood Hb level.


Asunto(s)
Eritropoyetina/sangre , Mieloma Múltiple/sangre , Adulto , Anciano , Ritmo Circadiano , Femenino , Humanos , Fallo Renal Crónico/sangre , Masculino , Persona de Mediana Edad , Radioinmunoensayo
20.
Gan To Kagaku Ryoho ; 15(6): 1929-33, 1988 Jun.
Artículo en Japonés | MEDLINE | ID: mdl-3382242

RESUMEN

The purposes of this administration were to inactivate cancer cells liberated from the primary tumor, to prevent them from metastasizing to other organs and to treat established metastatic cancer. Sixty-one patients with advanced gastric cancer who had received preoperative 5-FU dry syrup administration and who had also undergone curative resection between 1976 and 1982, in addition to postoperative chemotherapy (more than 20 mg MMC, 5,000 mg 5-FU), (Group A) were admitted to the present study. Their survival rate was compared with that of 67 patients given curative resection for advanced cancer without preoperative 5-FU dry syrup, who received the same postoperative chemotherapy only (Group B) during the same period. The 5-year survival rate for Group A was 0.55 +/- 0.06, higher than the rate of 0.42 +/- 0.06 for Group B. Comparing the 5-year survival rates of both groups in terms of clinicopathological factors such as stage of cancer progression, serosal invasion, lymph node metastasis, and lymphangitic and blood vessel invasion, the 5-year survival rates for Group A were higher than those for Group B. There were significant differences for histological stage III and blood vessel invasion between the two groups. From these results, it is suggested that preoperative oral 5-FU dry syrup might be effective as an adjuvant therapy to surgery for gastric cancer.


Asunto(s)
Fluorouracilo/administración & dosificación , Cuidados Preoperatorios , Neoplasias Gástricas/tratamiento farmacológico , Administración Oral , Adulto , Anciano , Terapia Combinada , Femenino , Gastrectomía/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/cirugía
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