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1.
Nutr Metab Cardiovasc Dis ; 26(9): 808-14, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27212620

RESUMEN

BACKGROUND AND AIMS: Findings of observational studies suggest cardioprotective effects of antioxidant vitamins and carotenoids. However, recent meta-analyses failed to show the beneficial effects of supplemental intake of antioxidants on cardiovascular disease (CVD). We aimed to assess the association between CVD risk and ß-cryptoxanthin in Japan, where Satsuma mandarin, a major source of ß-cryptoxanthin, is widely consumed. METHODS AND RESULTS: This was part of the Mikkabi cohort study. Surveys were conducted at baseline, in 2003 and 2005, and on follow-up in 2006, 2009, and 2013. We examined brachial-ankle pulse wave velocity (baPWV) with a high cut-off value set at 18.3 m s(-1). Hazard ratios (HR) and 95% confidence intervals for high baPWV were estimated using a Cox proportional hazards model with adjustment for potential confounders. A total of 635 participants with baPWV of less than 18.3 m s(-1) at baseline were included in the analysis. During the follow-up period of 57,921 person-months, 99 subjects developed high baPWV. After multivariate adjustment, the HR for high baPWV in the highest tertile compared with the lowest tertile was significantly low for ß-cryptoxanthin, ß-carotene, and total carotenoids. Serum concentrations of ß-cryptoxanthin and ß-carotene were higher in people who ate Satsuma mandarin frequently. Compared with <1/d intake of Satsuma mandarin, 3-4/d was associated with a low risk of high PWV. CONCLUSION: This study indicated that ß-cryptoxanthin and ß-carotene derived from Satsuma mandarin are candidate micronutrients for preventing arteriosclerosis development. Further longitudinal and interventional studies will be required to validate the effect on CVD.


Asunto(s)
Índice Tobillo Braquial , Arteriosclerosis/prevención & control , beta-Criptoxantina/sangre , Citrus , Dieta Saludable , Frutas , Análisis de la Onda del Pulso , beta Caroteno/sangre , Adulto , Anciano , Arteriosclerosis/sangre , Arteriosclerosis/diagnóstico , Arteriosclerosis/fisiopatología , beta-Criptoxantina/administración & dosificación , Femenino , Encuestas Epidemiológicas , Humanos , Japón , Masculino , Persona de Mediana Edad , Análisis Multivariante , Valor Predictivo de las Pruebas , Pronóstico , Estudios Prospectivos , Factores de Riesgo , Conducta de Reducción del Riesgo , Factores de Tiempo , beta Caroteno/administración & dosificación
3.
Eur Surg Res ; 34(4): 306-12, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12145557

RESUMEN

We studied the effect of hyperthermia pretreatment on subsequent small intestinal ischemia and reperfusion (I/R) injury in the rat. Systemic hyperthermia has been reported to induce heat shock proteins (HSPs) in several organs [1-6]. We examined the expression of HSP72 in the small intestinal mucosa using Western blotting and immunohistochemistry. We monitored energy metabolism using magnetic resonance spectroscopy continuously during a 60-min ischemia and the following 120 min of reperfusion. Expression of HSP72 in the small intestine was significantly increased at 6-8 h after hyperthermia. Intestinal ischemia was induced by clamping the superior mesenteric artery. Heating of the rat conferred substantial resistance to the I/R injury. In the untreated rats, beta-ATP decreased during ischemia (37.1 +/- 15.5% of the pre-ischemic value) and recovered on reperfusion, but reached only approximately 50% of the pre-ischemic value after 120 min of reperfusion. However, beta-ATP in the pretreated rats was maintained during ischemia at significantly higher levels and on reperfusion reached approximately 80% of the pre-ischemic value. These results indicate that hyperthermia protects the rat intestine from the I/R injury by unknown mechanisms which may include the induction of HSPs.


Asunto(s)
Adenosina Trifosfato/metabolismo , Hipertermia Inducida , Intestino Delgado/metabolismo , Daño por Reperfusión/patología , Daño por Reperfusión/terapia , Animales , Metabolismo Energético , Proteínas del Choque Térmico HSP72 , Proteínas de Choque Térmico/metabolismo , Intestino Delgado/patología , Espectroscopía de Resonancia Magnética , Masculino , Isótopos de Fósforo , Ratas , Ratas Wistar , Daño por Reperfusión/metabolismo
4.
Proc Natl Acad Sci U S A ; 98(25): 14446-51, 2001 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-11724922

RESUMEN

Conjugation in Blepharisma japonicum is induced by interaction between complementary mating-types I and II, which excrete blepharmone (gamone 1) and blepharismone (gamone 2), respectively. Gamone 1 transforms type II cells such that they can unite, and gamone 2 similarly transforms type I cells. Moreover, each gamone promotes the production of the other gamone. Gamone 2 has been identified as calcium-3-(2'-formylamino-5'-hydroxy-benzoyl) lactate and has been synthesized chemically. Gamone 1 was isolated and characterized as a glycoprotein of 20-30 kDa containing 175 amino acids and 6 sugars. However, the amino acid sequence and arrangement of sugars in this gamone are still unknown. To determine partial amino acid sequences of gamone 1, we established a method of isolation based on the finding that this glycoprotein can be concentrated by a Con A affinity column. Gamone 1 is extremely unstable and loses its biological activity once adsorbed to any of the columns that we tested. By using a Con A affinity column and native PAGE, we detected a 30-kDa protein corresponding to gamone 1 activity and determined the partial amino acid sequences of the four peptides. To isolate gamone 1 cDNA, we isolated mRNA from mating-type I cells stimulated by synthetic gamone 2 and then performed rapid amplification of cDNA ends procedures by using gene-specific primers and cloned cDNA of gamone 1. The cDNA sequence contains an ORF of 305 amino acids and codes a possibly novel protein. We also estimated the arrangement of sugars by comparing the affinity to various lectin columns.


Asunto(s)
Cilióforos/genética , Glicoproteínas/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Carbohidratos/química , Clonación Molecular , ADN Complementario/genética , ADN Protozoario/genética , Glicoproteínas/química , Glicoproteínas/aislamiento & purificación , Péptidos y Proteínas de Señalización Intercelular , Datos de Secuencia Molecular , Reproducción/genética
5.
Plant Mol Biol ; 44(2): 155-65, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11117259

RESUMEN

Intron-containing tRNA genes are exceptional within nuclear plant genomes. It appears that merely two tRNA gene families coding for tRNA(GpsiA(Tyr)) and elongator tRNA(CmAU(Met)) contain intervening sequences. We have previously investigated the features required by wheat germ splicing endonuclease for efficient and accurate intron excision from Arabidopsis pre-tRNA(Tyr). Here we have studied the expression of an Arabidopsis elongator tRNA(Met) gene in two plant extracts of different origin. This gene was first transcribed either in HeLa or in tobacco cell nuclear extract and splicing of intron-containing tRNA(Met) precursors was then examined in wheat germ S23 extract and in the tobacco system. The results show that conversion of pre-tRNA(Met) to mature tRNA proceeds very efficiently in both plant extracts. In order to elucidate the potential role of specific nucleotides at the 3' and 5' splice sites and of a structured intron for pre-tRNA(Met) splicing in either extract, we have performed a systematic survey by mutational analyses. The results show that cytidine residues at intron-exon boundaries impair pre-tRNA(Met) splicing and that a highly structured intron is indispensable for pre-tRNA(Met) splicing. tRNA precursors with an extended anticodon stem of three to four base pairs are readily accepted as substrates by wheat and tobacco splicing endonuclease, whereas pre-tRNA molecules that can form an extended anticodon stem of only two putative base pairs are not spliced at all. An amber suppressor, generated from the intron-containing elongator tRNA(Met) gene, is efficiently processed and spliced in both plant extracts.


Asunto(s)
Arabidopsis/genética , Precursores del ARN/genética , Empalme del ARN , ARN de Transferencia de Metionina/genética , Secuencia de Bases , Núcleo Celular/genética , Citidina/genética , Exones/genética , Células HeLa , Humanos , Intrones/genética , Datos de Secuencia Molecular , Estructura Molecular , Extractos Vegetales/metabolismo , Plantas Tóxicas , Precursores del ARN/química , Sitios de Empalme de ARN , ARN de Transferencia de Metionina/química , Homología de Secuencia de Ácido Nucleico , Supresión Genética , Nicotiana/citología , Triticum/química
6.
Contact Dermatitis ; 43(3): 157-60, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10985632

RESUMEN

We report the annual results of patch testing with lavender oil for a 9-year period from 1990 to 1998 in Japan. Using Finn Chambers and Scanpor tape, we performed 2-day closed patch testing with lavender oil 20% pet. on the upper back of each patient suspected of having cosmetic contact dermatitis. We compared the frequency of positive patch tests to lavender oil each year with those to other fragrances. We diagnosed contact allergy when patch test reactions were + or <+ at 1 day after removal. The positivity rate of lavender oil was 3.7% (0-13.9%) during the 9-year period from 1990 to 1998. The positivity rate of lavender oil increased suddenly in 1997. Recently, in Japan, there has been a trend for aromatherapy using lavender oil. With this trend, placing dried lavender flowers in pillows, drawers, cabinets, or rooms has become a new fashion. We asked patients who showed a positive reaction to lavender oil about their use of dried lavender flowers. We confirmed the use of dried lavender flowers in 5 cases out of 11 positive cases in 1997 and 8 out of 15 positive cases in 1998. We concluded that the increase in patch test positivity rates to lavender oil in 1997 and 1998 was due to the above fashion, rather than due to fragrances in cosmetic products.


Asunto(s)
Cosméticos/efectos adversos , Dermatitis por Contacto , Dermatitis por Contacto/etiología , Aceites Volátiles/efectos adversos , Extractos Vegetales/efectos adversos , Aceites de Plantas , Adolescente , Adulto , Anciano , Aromaterapia/efectos adversos , Dermatitis por Contacto/diagnóstico , Dermatitis por Contacto/epidemiología , Femenino , Humanos , Japón/epidemiología , Lavandula , Masculino , Persona de Mediana Edad , Pruebas del Parche , Perfumes/efectos adversos
7.
J Neurophysiol ; 84(3): 1656-66, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10980035

RESUMEN

This study describes the functional anatomy of olfactory and visual naming and matching in humans, using positron emission tomography (PET). One baseline control task without olfactory or visual stimulation, one control task with simple olfactory and visual stimulation without cognition, one set of olfactory and visual naming tasks, and one set of olfactory and visual matching tasks were administered to eight normal volunteers. In the olfactory naming task (ON), odors from familiar items, associated with some verbal label, were to be named. Hence, it required long-term olfactory memory retrieval for stimulus recognition. The olfactory matching task (OM) involved differentiating a recently encoded unfamiliar odor from a sequentially presented group of unfamiliar odors. This required short-term olfactory memory retrieval for stimulus differentiation. The simple olfactory and visual stimulation resulted in activation of the left orbitofrontal region, the right piriform cortex, and the bilateral occipital cortex. During olfactory naming, activation was detected in the left cuneus, the right anterior cingulate gyrus, the left insula, and the cerebellum bilaterally. It appears that the effort to identify the origin of an odor involved semantic analysis and some degree of mental imagery. During olfactory matching, activation was observed in the left cuneus and the cerebellum bilaterally. This identified the brain areas activated during differentiation of one unlabeled odor from the others. In cross-task analysis, the region found to be specific for olfactory naming was the left cuneus. Our results show definite recruitment of the visual cortex in ON and OM tasks, most likely related to imagery component of these tasks. The cerebellar role in cognitive tasks has been recognized, but this is the first PET study that suggests that the human cerebellum may have a role in cognitive olfactory processing as well.


Asunto(s)
Mapeo Encefálico , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Olfato/fisiología , Tomografía Computarizada de Emisión , Adolescente , Adulto , Análisis de Varianza , Cerebelo/diagnóstico por imagen , Cerebelo/fisiología , Lóbulo Frontal/diagnóstico por imagen , Lóbulo Frontal/fisiología , Giro del Cíngulo/diagnóstico por imagen , Giro del Cíngulo/fisiología , Humanos , Masculino , Memoria a Corto Plazo/fisiología , Lóbulo Occipital/diagnóstico por imagen , Lóbulo Occipital/fisiología , Odorantes , Vías Olfatorias/diagnóstico por imagen , Vías Olfatorias/fisiología , Estimulación Luminosa , Estimulación Química
8.
Neurosci Res ; 38(4): 331-9, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11164559

RESUMEN

To clarify the antinociceptive mechanism of acupuncture on acute pain, c-fos protein (Fos) expression induced by tooth pulp stimulation was immunohistochemically examined in the spinal trigeminal subnucleus pars caudalis (spVc) and the periaqueductal gray (PAG) of rats with or without Neiting acupuncture. The central projection of trigeminal ganglion neurons innervating in the tooth pulp was examined by tract-tracing method with horseradish peroxidase-conjugated wheat germ agglutinin (WGA-HRP). Central terminals from the first maxillary molar tooth were labeled transganglionically in the dorsomedial part of spVc with WGA-HRP. Numerous numbers of Fos-immunoreactive (Fos-ir) cells were found in the spVc and PAG by stimulation of the tooth pulp with acetic acid or saline. Neiting acupuncture significantly reduced the Fos expression in the spVc induced by tooth pulp stimulation. On the other hand, Neiting acupuncture evoked many Fos-ir cells in the PAG. The present results suggest that Neiting acupuncture activated PAG neurons that sent descending inhibitory fibers to medullo-spinal nociceptive neurons, and reduced the number of Fos-expressed neurons in the trigeminal subnucleus pars caudalis mediating noxious information from teeth to the higher central nervous system.


Asunto(s)
Analgesia por Acupuntura , Nociceptores/metabolismo , Sustancia Gris Periacueductal/metabolismo , Proteínas Proto-Oncogénicas c-fos/metabolismo , Odontalgia/terapia , Núcleo Caudal del Trigémino/metabolismo , Animales , Pulpa Dental/metabolismo , Femenino , Pie/inervación , Pie/fisiología , Inmunohistoquímica , Vías Nerviosas/citología , Vías Nerviosas/metabolismo , Neuronas/citología , Neuronas/metabolismo , Sustancia Gris Periacueductal/citología , Ratas , Ratas Wistar , Odontalgia/fisiopatología , Núcleo Caudal del Trigémino/citología , Ganglio del Trigémino/citología , Ganglio del Trigémino/metabolismo
9.
J Med Chem ; 41(16): 2985-93, 1998 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-9685237

RESUMEN

In continuation of our previous work on eosinophilia inhibitors, we synthesized an additional series of inhibitors, which consisted of 5-amino-1-[(methylamino)thiocarbonyl]-1H-1,2,4-triazole derivatives and a newly developed series of 1,2,4-triazolo[1,5-a]-1,3,5-triazine derivatives. We evaluated their inhibitory activity on the airway eosinophilia model, which was induced by the intravenous (iv) injection of Sephadex particles. In the 1,2,4-triazole series with various substituents at the 3 position of the triazole ring such as 2-furyl, pyridyl, and phenoxy, none of derivatives had comparable activity to the previously reported compound GCC-AP0341, 5-amino-3-(4-chlorophenyl)-1-[(methylamino)thiocarbonyl]-1H-1,2, 4-triazole. In the triazolo[1,5-a]triazine series, 2-(4-chlorophenyl)-6-methyl-1,2,4-triazolo[1,5-a]-1,3, 5-triazine-7(6H)-thione (3h) was highly potent, and when given orally it had an ID50 value of 0.3 mg/kg, which is comparable to that of GCC-AP0341. The fact that the structure-activity relationship of these two series was quite similar suggests that a common substructure, such as the 1,2,4-triazole ring with a substituted phenyl ring at the 3 position and a thiocarbonyl moiety at the 1 position, could contribute to the activity. Our selected compound 3h was less active than GCC-AP0341 in the antigen-induced hyper-responsiveness model in guinea pigs; however, we plan to carry out further studies on eosinophil functions, especially on their activation, using our two compounds, 3h and GCC-AP0341.


Asunto(s)
Antiasmáticos , Eosinofilia Pulmonar/prevención & control , Triazinas , Triazoles , Animales , Antiasmáticos/síntesis química , Antiasmáticos/química , Antiasmáticos/farmacología , Antígenos Helmínticos/inmunología , Ascaris/inmunología , Asma/tratamiento farmacológico , Asma/inmunología , Recuento de Células/efectos de los fármacos , Dextranos/toxicidad , Evaluación Preclínica de Medicamentos , Eosinófilos/citología , Eosinófilos/efectos de los fármacos , Cobayas , Humanos , Técnicas In Vitro , Masculino , Eosinofilia Pulmonar/inducido químicamente , Eosinofilia Pulmonar/inmunología , Hipersensibilidad Respiratoria/tratamiento farmacológico , Hipersensibilidad Respiratoria/inmunología , Relación Estructura-Actividad , Triazinas/síntesis química , Triazinas/química , Triazinas/farmacología , Triazoles/síntesis química , Triazoles/química , Triazoles/farmacología
10.
Plant J ; 12(1): 215-21, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9263462

RESUMEN

In this study, a cDNA encoding a small RNA-binding protein was isolated from a Nicotiana sylvestris cDNA library. The predicted protein (RGP-3) is 144 amino acid residues long, and contains a consensus sequence-type RNA binding domain (CS-RBD) of 83 amino acids and a short glycine-rich region of 15 amino acids. RGP-3 synthesized in Escherichia coli has high affinity for poly(U). Immunocytochemical analysis indicated that RGP-3 is localized in the nucleoplasm, and that RGP-1b, a related protein reported previously, is localized in the nucleolus. Possible roles of these proteins in pre-mRNA or pre-rRNA processing are discussed.


Asunto(s)
Nicotiana/metabolismo , Proteínas Nucleares/biosíntesis , Proteínas Nucleares/química , Proteínas de Plantas , Plantas Tóxicas , Proteínas de Unión al ARN/biosíntesis , Proteínas de Unión al ARN/química , Secuencia de Aminoácidos , Secuencia de Bases , Sitios de Unión , Secuencia Conservada , ADN Complementario , Biblioteca de Genes , Genes de Plantas , Glicina , Datos de Secuencia Molecular , Proteínas Nucleares/análisis , Oligodesoxirribonucleótidos , Proteínas de Unión al ARN/análisis , Fracciones Subcelulares/metabolismo , Fracciones Subcelulares/ultraestructura , Nicotiana/genética , Nicotiana/ultraestructura
11.
Planta Med ; 63(3): 196-8, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9225598

RESUMEN

Several 13-alkyl substituted analogs of berberine and palmatine were found to be highly active against two types of Staphylococcus aureus (S1 and S2) of different origin. The most active 13-hexylberberine was 8 times more active (against S1) and the same order active (against S2) as kanamycin sulfate. 13-Hexylpalmatine displayed an activity against S. aureus (S1) 4 times greater than that of kanamycin sulfate. The activities of 13-hexylberberine against two types of S. aureus were 64 and 128 times greater than those of the clinically used alkaloid berberine. Additionally two hexyl derivatives possessed antifungal activity.


Asunto(s)
Alcaloides de Berberina/farmacología , Berberina/análogos & derivados , Berberina/farmacología , Staphylococcus aureus/efectos de los fármacos , Berberina/química , Alcaloides de Berberina/química , Pruebas de Sensibilidad Microbiana , Relación Estructura-Actividad
12.
Int J Immunopharmacol ; 19(1): 15-24, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9226475

RESUMEN

Dipeptidyl peptidase IV (DP IV, CD26) is a serine exoprotease which selectively cleaves the penultimate proline residue of polypeptides. This enzyme is also expressed as a surface marker on activated T cells. In order to assess the relevance of DP IV in immunological disorders, we evaluated the in vivo effects of specific DP IV inhibitors using two arthritis models, one which was induced by collagen one by alkyldiamine. These animal models share several pathological features associated with rheumatoid arthritis. The transition state substrate analog of DP IV, (S)-Alanylpyrrolidine-boronic Acid (Ala-boroPro), suppressed hind paw swelling, which was associated with collagen-induced and alkyldiamine-induced arthritis. A competitive inhibitor of DP IV, Lys(Z(NO2))-thiazolidide and an irreversible inhibitor, Ala-Pro-nitrobenzoylhydroxylamine also suppressed alkyldiamine-induced arthritis dose-dependently. We also analyzed the pharmacological effects of Lys(Z(NO2))-thiazolidide on several immune responses in vitro, in order to determine its mode of action. This inhibitor suppressed mitogen-induced and antigen-induced proliferation of T cells. However, studies using splenic cells from DP IV deficient rats showed that the inhibition of lymphocyte proliferation was not exerted through the inhibition of DP IV.


Asunto(s)
Artritis Reumatoide/tratamiento farmacológico , Dipéptidos/farmacología , Dipéptidos/uso terapéutico , Dipeptidil Peptidasa 4/fisiología , Hidroxilaminas/farmacología , Inmunosupresores/uso terapéutico , Lisina/análogos & derivados , Inhibidores de Serina Proteinasa/farmacología , Linfocitos T/efectos de los fármacos , Tiazoles/farmacología , Animales , Artritis Reumatoide/inducido químicamente , Artritis Reumatoide/inmunología , Ácidos Borónicos/farmacología , Ácidos Borónicos/uso terapéutico , Células Cultivadas , Colágeno/toxicidad , Diaminas/toxicidad , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos , Femenino , Inmunosupresores/farmacología , Activación de Linfocitos/efectos de los fármacos , Lisina/farmacología , Modelos Inmunológicos , Ratas , Ratas Endogámicas F344 , Ratas Endogámicas Lew , Linfocitos T/enzimología , Linfocitos T/inmunología
13.
Biochim Biophys Acta ; 1308(3): 231-40, 1996 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-8809115

RESUMEN

A cDNA library constructed from poly(A)+ RNA of tobacco BY2 cells treated with 2,4-dichlorophenoxyacetic acid was screened by using a synthetic oligonucleotide corresponding to the heme binding region of avocado CYP71A1. A cloned 2-kb cDNA designated as cTBP contained an open reading frame of 1593 bp encoding a protein of molecular size of 58916. The deduced amino acid sequence included a cysteine residue corresponding to fifth ligand of heme-Fe at 497th. The coding sequence was expressed under the control of tac promoter and rrnB terminator in Escherichia coli to yield 7 to 10 nmol P450 equivalent per litre of the culture in the presence of delta-aminolevulinic acid. The modified coding sequences in which NH2-terminal residues 2-25 were replaced by the NH2-terminal 18 amino acid residues of microsomal bovine CYP17 were also expressed under the control of ADH promoter and terminator in Saccharomyces cerevisiae to yield 29 and 30 pmol of P450 equivalent/mg protein in the microsomal fraction, respectively. On co-expression of each of the modified coding sequences and yeast NADPH-cytochrome P-450 oxidoreductase gene, the yeast microsomes exhibited 7-ethoxycoumarin O-deethylase activity. Based on these results, tobacco cTBP was found to encode a novel P450-like species with a monooxygenese activity related to xenobiotic metabolism.


Asunto(s)
Clonación Molecular , Sistema Enzimático del Citocromo P-450/genética , Escherichia coli/genética , Nicotiana/genética , Plantas Tóxicas , Saccharomyces cerevisiae/genética , Ácido 2,4-Diclorofenoxiacético/farmacología , 7-Alcoxicumarina O-Dealquilasa/metabolismo , Secuencia de Aminoácidos , Secuencia de Bases , Northern Blotting , Células Cultivadas , Sistema Enzimático del Citocromo P-450/química , Sondas de ADN , ADN Complementario/genética , Electroforesis en Gel de Poliacrilamida , Expresión Génica , Microsomas/enzimología , Datos de Secuencia Molecular , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Espectrofotometría , Nicotiana/enzimología
14.
Plant Mol Biol ; 31(1): 57-68, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8704159

RESUMEN

A cDNA encoding a protein with a consensus sequence-type RNA-binding domain (CS-RBD) has been isolated from a Nicotiana sylvestris cDNA library. The deduced protein (designated 'RZ-1') contains CS-RBD in its N-terminal half, arginine/aspartic acid repeats in its center and a glycine-rich-C-terminal region in which a zinc finger motif of the CCHC type is present. The corresponding gene appears to be expressed constitutively in all tobacco organs. Immunocytochemical assays revealed that RZ-1 is localized in the nucleoplasm of tobacco cultured cells. Glycerol gradient fractionation of tobacco nuclear lysates showed that RZ-1 is associated with a large ribonucleoprotein particle of around 60 S in size. Nucleic acid-binding assays indicated that RZ-1 binds preferentially to poly (G) and both the CS-RBD and glycine-rich region are necessary for its binding activity. A possible role of RZ-1 is discussed.


Asunto(s)
Núcleo Celular/metabolismo , Nicotiana/metabolismo , Proteínas de Plantas/genética , Plantas Tóxicas , Proteínas de Unión al ARN/genética , Ribonucleoproteínas/metabolismo , Secuencia de Aminoácidos , Secuencia de Bases , ADN Complementario , Glicerol , Datos de Secuencia Molecular , Proteínas de Plantas/aislamiento & purificación , Proteínas de Plantas/metabolismo , Poli G/metabolismo , Unión Proteica , Proteínas de Unión al ARN/aislamiento & purificación , Proteínas de Unión al ARN/metabolismo , Nicotiana/citología
16.
Plant J ; 8(2): 295-8, 1995 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7670508

RESUMEN

An in vitro transcription system derived from tobacco (Nicotiana tabacum) cultured cell (BY-2) nuclei supports transcription of the RNA polymerase I-dependent tobacco rRNA gene. The transcription initiation site determined in vitro was found at residue A which corresponds to that lying within the consensus sequence surrounding plant pre-rRNA initiation sites. The tobacco rRNA gene is actively transcribed in the tobacco nuclear extract while the broad bean rRNA gene is inactive in the heterologous system, indicating that plant RNA polymerase I-dependent transcription is species-specific.


Asunto(s)
ADN Ribosómico/genética , Plantas/genética , ARN Polimerasa I/metabolismo , ARN Ribosómico/biosíntesis , Transcripción Genética , Secuencia de Bases , Núcleo Celular/metabolismo , Fabaceae/genética , Datos de Secuencia Molecular , Plantas Medicinales , Plantas Tóxicas , Especificidad de la Especie , Fracciones Subcelulares/metabolismo , Nicotiana/genética
17.
J Pharmacol Exp Ther ; 271(2): 703-7, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7965785

RESUMEN

The effects of crocin (crocetin di-gentiobiose ester) and its analogs on long-term potentiation (LTP) of evoked potential in the dentate gyrus were investigated by using anesthetized rats. Intracerebroventricular injection of crocin (51.2 nmol) alone did not affect the synaptic potential evoked by single stimulation of the medial perforant path, and neither inhibited nor facilitated the LTP induced by strong (30 pulses at 60 Hz) or weak (20 pulses at 60 Hz) tetanus. Administration of ethanol (30 v/v%, 2 ml/kg i.v.) blocked the LTP induced by application of tetanus (30 pulses at 60 Hz), but the LTP-blocking effect of ethanol was prevented by preadministration of crocin (51.2 nmol i.c.v.). Crocetin gentiobiose glucose ester also antagonized the LTP-blocking effect of ethanol, but it required a higher dose (102.5 nmol i.c.v.) to exhibit a more significant effect than crocin. Crocetin di-glucose ester at a dose up to 102.5 nmol (i.c.v.) did not significantly affect the LTP-blocking effect of ethanol. Neither gentiobiose alone (102.5 nmol i.c.v.) nor glucose alone (204.9 nmol i.c.v.) mimicked the activity of crocin. These results suggest that crocin can prevent the ethanol-induced impairment of hippocampal synaptic plasticity in vivo and that gentiobioses attached to the fatty acid chain are important for crocin to exert the biological activity.


Asunto(s)
Carotenoides/farmacología , Etanol/toxicidad , Hipocampo/efectos de los fármacos , Potenciación a Largo Plazo/efectos de los fármacos , Animales , Hipocampo/fisiología , Masculino , Memoria/efectos de los fármacos , Extractos Vegetales/farmacología , Ratas , Ratas Wistar , Vitamina A/análogos & derivados
18.
Biol Pharm Bull ; 17(2): 217-21, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8205119

RESUMEN

The acute effects of an alcohol extract of Crocus sativus L. (CS-extract) were studied on learning and memory in step through (ST) and step down (SD) tests in normal as well as in learning- and memory-impaired mice. A single oral administration of CS-extract had no effects on memory registration, consolidation or retrieval in normal mice. CS-Extract reduced the ethanol-induced impairment of memory registration both in ST and SD tests and the ethanol-induced impairment of memory retrieval in SD test. CS-Extract decreased the motor activity (MA) and prolonged the sleeping time induced by hexobarbital. These results suggested that CS-extract ameliorates the impairment effects of ethanol on learning and memory processes, and possesses a sedative effect.


Asunto(s)
Reacción de Prevención/efectos de los fármacos , Etanol/toxicidad , Memoria/efectos de los fármacos , Actividad Motora/efectos de los fármacos , Extractos Vegetales/farmacología , Administración Oral , Análisis de Varianza , Animales , Defecación/efectos de los fármacos , Masculino , Ratones , Extractos Vegetales/administración & dosificación , Sueño/efectos de los fármacos , Micción/efectos de los fármacos
19.
Am Rev Respir Dis ; 148(3): 569-77, 1993 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8368625

RESUMEN

We evaluated four ventilator patterns after the administration of 80 mg/kg bovine lipid extract surfactant (LES) to anesthetized, paralyzed, saline-lavaged New Zealand white rabbits. Two ventilator types were compared: high frequency oscillatory ventilation (HFO) versus conventional mechanical ventilation (CMV), each at high (HI) and low (LO) end-expiratory lung volumes (EELV); n = 6, each group; treatment duration = 4 h. Target PaO2 ranges were > 350 mm Hg for groups with high EELV (i.e., HFO-HI and CMV-HI) and 70 to 100 mm Hg for those with low EELV (i.e., HFO-LO and CMV-LO). Ventilator pressures were limited to < or = 39/9 cm H2O in the CMV-HI group. Five of six CMV-HI-treated animals did not maintain target PaO2 levels. Both ventilator type and strategy influenced outcome significantly. Animals managed with HFO had higher mean arterial pressures (p = 0.004), lower mean airway pressures (Paw) (p < 0.00008) and HCO3- requirements (p < 0.02), larger inflation (p = 0.003) and deflation (p < 0.00001) respiratory system volumes at 10 cm inflation pressure, and higher lung lamellar body (p = 0.0006) and lavage fluid (p = 0.003) phospholipid quantities than did CMV-treated animals. The deflation P-V curve (p = 0.0004), lamellar body (p < 0.00001) and lavage fluid (p = 0.0002) phospholipid levels were superior after the high EELV strategy. We conclude that ventilator pattern strongly influences exogenous surfactant efficacy. Benefits arise from keeping EELV high enough to prevent atelectasis and using small (approximately 2 ml/kg) tidal volumes to prevent overdistension.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Alveolos Pulmonares/fisiología , Surfactantes Pulmonares/uso terapéutico , Respiración Artificial/métodos , Análisis de Varianza , Animales , Líquido del Lavado Bronquioalveolar/química , Evaluación Preclínica de Medicamentos , Pulmón/química , Fosfolípidos/análisis , Intercambio Gaseoso Pulmonar , Surfactantes Pulmonares/deficiencia , Conejos , Distribución Aleatoria , Respiración Artificial/instrumentación , Respiración Artificial/estadística & datos numéricos , Mecánica Respiratoria , Factores de Tiempo
20.
Chem Pharm Bull (Tokyo) ; 39(3): 566-71, 1991 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2070439

RESUMEN

During the course of our screening of bioactive natural products, three new saponins named periandradulcins A (1), B (2) and C (3) were isolated as phosphodiesterase (PDE, EC 3.1.4.17) inhibitors from 80% MeOH extract of the roots of Periandra dulcis Mart. (Leguminosae) by a combination of column chromatography and reversed- and normal-phase high-performance liquid chromatography (HPLC). On the basis of 1H-, 13C- and two-dimensional nuclear magnetic resonance (NMR) spectral data and chemical evidence, their chemical structures were characterized as 3-O-beta-[alpha-L-rhamnopyranosyl(1----2)-beta-D-xylopyranosyl(1----2)-b eta-D- glucuronopyranosyl]-30-hydroxyl-25-formylolean-18-ene-22 beta-O-syringate, 3-O-beta-[alpha-L-rhamnopyranosyl(1----2)-beta-D- xylopyranosyl(1----2)-beta-D-glucuronopyranosyl]-22 beta-hydroxyl-25- formylolean-12-ene and 3-O-beta-[alpha-L-rhamnopyranosyl(1----2)-beta-D- glucopyranosyl(1----2)-beta-D-glucuronopyranosyl]-22 beta-hydroxyl-25-formylolean-18-ene, respectively. The concentrations of periandradulcins A, B and C required to give 50% inhibition (IC50 values) of PDE from bovine heart, were 0.033, 7.6 and 7.7 microM, respectively. Compound 1 was the most potent among the known PDE inhibitors; it inhibited PDE-I (IC50:0.0022 microM) twenty and forty times more effectively than PDE-II and -III, respectively.


Asunto(s)
Fabaceae/análisis , Ácido Oleanólico/análogos & derivados , Inhibidores de Fosfodiesterasa/aislamiento & purificación , Plantas Medicinales , Saponinas/aislamiento & purificación , Secuencia de Carbohidratos , Datos de Secuencia Molecular , Inhibidores de Fosfodiesterasa/química , Saponinas/química , Saponinas/farmacología
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