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2.
Biochem Biophys Res Commun ; 277(2): 305-10, 2000 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-11032722

RESUMEN

Plant-plant interactions via herbivory-induced leaf volatiles could result in the induction of defense responses against aggressive biotic agents in plants. In this study, cDNA microarray technology showed comprehensive gene activation in lima bean leaves that were exposed to volatiles released from the neighboring leaves infested with spider mites. The infestation with spider mites and the herbivory-induced volatiles enhanced 97 and 227 gene spots on the microarray tip printed with 2032 lima bean cDNA, respectively. These genes are related to such broad functions as responses to pathogenesis, wounding, hormones, ethylene biosynthesis, flavonoid biosynthesis, (post) transcriptional modifications, translations, chaperones, secondary signaling messengers, membrane transports, protein/peptide degradations, and photosynthesis. We therefore conclude that herbivorous damage and herbivory-induced volatiles elicit comprehensive and drastic changes of metabolisms in leaves.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Regulación de la Expresión Génica , Animales , Ciclopentanos/metabolismo , ADN Complementario/metabolismo , Fabaceae/genética , Fabaceae/metabolismo , Colorantes Fluorescentes/metabolismo , Ácaros/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Oxilipinas , Plantas Medicinales , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal , Activación Transcripcional
3.
Nature ; 406(6795): 512-5, 2000 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-10952311

RESUMEN

In response to herbivore damage, several plant species emit volatiles that attract natural predators of the attacking herbivores. Using spider mites (Tetranychus urticae) and predatory mites (Phytoseiulus persimilis), it has been shown that not only the attacked plant but also neighbouring plants are affected, becoming more attractive to predatory mites and less susceptible to spider mites. The mechanism involved in such interactions, however, remains elusive. Here we show that uninfested lima bean leaves activate five separate defence genes when exposed to volatiles from conspecific leaves infested with T. urticae, but not when exposed to volatiles from artificially wounded leaves. The expression pattern of these genes is similar to that produced by exposure to jasmonic acid. At least three terpenoids in the volatiles are responsible for this gene activation; they are released in response to herbivory but not artificial wounding. Expression of these genes requires calcium influx and protein phosphorylation/dephosphorylation.


Asunto(s)
Ácido Egtácico/análogos & derivados , Fabaceae/fisiología , Plantas Medicinales , Acetatos/farmacología , Animales , Ciclopentanos/farmacología , Ácido Egtácico/farmacología , Fabaceae/efectos de los fármacos , Fabaceae/genética , Fabaceae/metabolismo , Femenino , Regulación de la Expresión Génica de las Plantas , Lipooxigenasa/biosíntesis , Lipooxigenasa/genética , Ácaros/fisiología , Aceites Volátiles/metabolismo , Oxilipinas , Aceites de Plantas/metabolismo , Proteínas de Plantas/genética , Salicilatos/farmacología , Terpenos/metabolismo , Activación Transcripcional , Volatilización
4.
Plant Cell Physiol ; 41(4): 391-8, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10845451

RESUMEN

We compared volatiles from lima bean leaves (Phaseolus lunatus) infested by either beet armyworm (Spodoptera exigua), common armyworm [Mythimna (Pseudaletia) separata], or two-spotted spider mite (Tetranychus urticae). We also analyzed volatiles from the leaves treated with jasmonic acid (JA) and/or methyl salicylate (MeSA). The volatiles induced by aqueous JA treatment were qualitatively and quantitatively similar to those induced by S. exigua or M. separata damage. Furthermore, both S. exigua and aqueous JA treatment induced the expression of the same basic PR genes. In contrast, gaseous MeSA treatment, and aqueous JA treatment followed by gaseous MeSA treatment, induced volatiles that was qualitatively and quantitatively more similar to the T. urticae-induced volatiles than those induced by aqueous JA treatment. In addition, T. urticae damage resulted in the expression of the acidic and basic PR genes that were induced by gaseous MeSA treatment and by aqueous JA treatment, respectively. Based on these data, we suggest that in lima bean leaves, the JA-related signaling pathway is involved in the production of caterpillar-induced volatiles, while both the SA-related signaling pathway and the JA-related signaling pathway are involved in the production of T. urticae-induced volatiles.


Asunto(s)
Ciclopentanos/farmacología , Interacciones Huésped-Parásitos , Insectos , Reguladores del Crecimiento de las Plantas/farmacología , Hojas de la Planta/efectos de los fármacos , Salicilatos/farmacología , Animales , Fabaceae , Larva , Oxilipinas , Hojas de la Planta/parasitología , Plantas Medicinales , Transducción de Señal , Terpenos/análisis , Volatilización
5.
J Nat Prod ; 61(11): 1413-5, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9834167

RESUMEN

Methanol extracts of Scutellaria baicalensis, Rheum officinale, and Paeonia suffruticosa showed potent inhibitory activity against rat intestinal sucrase. The active principles were identified as baicalein from the first and methyl gallate from the last two plants. In addition to its activity against the rat enzyme, baicalein also inhibited human intestinal sucrase expressed in Caco-2 cells.


Asunto(s)
Inhibidores Enzimáticos/aislamiento & purificación , Flavanonas , Flavonoides/aislamiento & purificación , Glucano 1,4-alfa-Glucosidasa/antagonistas & inhibidores , Plantas Medicinales/química , Animales , Células CACO-2 , Inhibidores Enzimáticos/farmacología , Flavonoides/farmacología , Humanos , Técnicas In Vitro , Intestinos/efectos de los fármacos , Intestinos/enzimología , Masculino , Ratas , Sacarasa/antagonistas & inhibidores
6.
Clin Ther ; 20(3): 477-85, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9663363

RESUMEN

The use of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors has become common in the treatment of hypercholesterolemia. The present uncontrolled study was undertaken to determine the effect of cerivastatin sodium (BAY w 6228), a new HMG-CoA reductase inhibitor, on biliary lipid levels in patients with hypercholesterolemia. Twenty-one hypercholesterolemic patients (World Health Organization type IIa = 16 patients; type IIb = 5 patients) received placebo during a 4- to 6-week observation period, after which they received cerivastatin sodium 0.2 mg/d for 12 weeks. Fasting blood samples were drawn for the measurement of serum lipid levels early in the morning before the start of treatment and once a month for each of the 12 weeks of cerivastatin sodium treatment. Gallbladder bile samples were aspirated with a duodenal tube by cerulein stimulation to assess bile lithogenicity. Serum total cholesterol levels decreased markedly after 12 weeks. However, no significant difference was found in the molar percentage composition of biliary lipids (e.g., cholesterol, phospholipids, and total bile acids) or in individual biliary bile acids. Consequently, no significant change in bile cholesterol saturation index was found. The index values before and after 12 weeks of treatment were 0.81 +/- 0.38 and 0.80 +/- 0.47, respectively, whereas when patients were grouped by type of hypercholesterolemia, there was a tendency toward decreased lithogenicity in patients with type IIb but not type IIa hypercholesterolemia. We concluded that cerivastatin sodium was an effective cholesterol-lowering drug that did not appear to worsen biliary lipid metabolism and that may decrease lithogenicity in patients with type IIb hypercholesterolemia.


Asunto(s)
Bilis/metabolismo , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Hipercolesterolemia/tratamiento farmacológico , Hipolipemiantes/uso terapéutico , Metabolismo de los Lípidos , Piridinas/uso terapéutico , Adulto , Anciano , Bilis/efectos de los fármacos , Ácidos y Sales Biliares/metabolismo , Colesterol/sangre , Dieta , Ácidos Grasos/metabolismo , Femenino , Humanos , Hipercolesterolemia/metabolismo , Lípidos/sangre , Masculino , Persona de Mediana Edad , Fosfatidilcolinas/metabolismo , Triglicéridos/sangre
7.
Endocr J ; 43(2): 233-9, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9026270

RESUMEN

In an attempt to define the hypothalamic-pituitary-adrenal (HPA) axis in non-insulin dependent diabetic rats (WBN/Kob), we measured plasma corticotropin releasing factor (CRF), as well as arginine vasopressin (AVP), ACTH, and corticosterone (B), CRF concentrations in the median eminence (ME), the remainder of the hypothalamus (rHY) and the neurointermediate lobe of the pituitary (NIL). We also measured Iodine-125-labeled ovine CRF ([125I]oCRF) binding in the brain and peripheral tissues. Body and thymus weight in WBN/Kob rats were significantly lower than in control Wistar rats, but adrenal weight was higher in WBN/Kob rats. Plasma ACTH levels were significantly higher in WBN/Kob rats than in the control rats. However, plasma CRF, AVP and B levels in WBN/Kob rats were not different from those in the control rats. The CRF concentration was significantly decreased in the ME of the diabetic rats, compared with control rats, but CRF concentrations in the rHY and NIL were unchanged in the two groups. A significant reduction in [125I]oCRF binding in the anterior pituitary was demonstrated in WBN/Kob rats, but no significant difference between the diabetic and control rats in CRF binding was observed in the frontal cortex, spleen or adrenal gland. These findings suggest that the HPA axis is chronically stimulated in the non-insulin dependent diabetic rats.


Asunto(s)
Glándulas Suprarrenales/fisiopatología , Diabetes Mellitus Tipo 2/fisiopatología , Hipotálamo/fisiopatología , Hipófisis/fisiopatología , Glándulas Suprarrenales/patología , Hormona Adrenocorticotrópica/sangre , Animales , Arginina Vasopresina/sangre , Glucemia/metabolismo , Peso Corporal , Encéfalo/metabolismo , Corticosterona/sangre , Hormona Liberadora de Corticotropina/sangre , Hormona Liberadora de Corticotropina/metabolismo , Diabetes Mellitus Tipo 2/patología , Insulina/sangre , Radioisótopos de Yodo , Masculino , Tamaño de los Órganos , Ratas , Ratas Mutantes , Ratas Wistar , Timo/patología
8.
Brain Res ; 649(1-2): 265-70, 1994 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-7953641

RESUMEN

We measured iodine-125-labeled recombinant human interleukin-1 alpha (125I-IL-1 alpha) binding in the hippocampus, pituitary, liver, spleen and testis, and plasma adrenocorticotropic hormone (ACTH) and corticosterone levels after i.p. injection of various dose and treatment regimens of the bacterial endotoxin, lipopolysaccharide (LPS). Plasma ACTH and corticosterone levels were significantly increased at 2 h after acute administration of LPS (60 or 300 micrograms/mouse). 125I-IL-1 alpha binding in all peripheral tissues examined was significantly and comparably decreased at 2 h after a single injection of 30 micrograms or 300 micrograms LPS/mouse. On the other hand, 125I-IL-1 alpha binding in hippocampus was significantly decreased only after high dose administration of LPS (300 micrograms/mouse). In order to evaluate if activation of IL-1 in brain resulting in the observed decrease in 125I-IL-1 alpha binding may require more sustained exposure to endotoxin, we compared the effects of a single injection (60 micrograms/mouse) and two injections of LPS (30 micrograms/mouse each at 0 and 12 h). A single injection of LPS (60 micrograms/mouse) decreased 125I-IL-1 alpha binding in the testis but not in the hippocampus, while two LPS injections (30 micrograms/mouse each at 0 and 12 h) caused dramatic reductions in 125I-IL-1 alpha binding in both the hippocampus and testis.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Sistema Hipotálamo-Hipofisario/metabolismo , Interleucina-1/metabolismo , Lipopolisacáridos/farmacología , Sistema Hipófiso-Suprarrenal/metabolismo , Receptores de Interleucina/biosíntesis , Hormona Adrenocorticotrópica/sangre , Animales , Corticosterona/sangre , Sistema Hipotálamo-Hipofisario/efectos de los fármacos , Radioisótopos de Yodo , Masculino , Ratones , Ratones Endogámicos C57BL , Sistema Hipófiso-Suprarrenal/efectos de los fármacos , Receptores de Interleucina/efectos de los fármacos
9.
Nihon Igaku Hoshasen Gakkai Zasshi ; 53(12): 1371-4, 1993 Dec 25.
Artículo en Japonés | MEDLINE | ID: mdl-8108241

RESUMEN

We examined lymphography as an interventional radiological technique for suppressing microscopic metastasis to the pelvic and paraaortic lymph nodes. There were no reports on this method in our survey of the literature. We performed a dose-escalation study as a phase I trial to determine the maximum dose that could be given without intolerable complications. From September 1991 to April 1992, carboplatin and iodized-oil emulsion was injected into both feet of 10 patients by the Kinmonth method. In the first 5 patients 5 mg of carboplatin was injected into each foot, and 10 mg was injected in the next 5 patients. When the injection of 15 mg was attempted, the injection could not be completed because carboplatin powder was deposited in the syringe. The amount of carboplatin was limited by the instability of the carboplatin-lipiodol emulsion at 15 mg in the present study. There were not intolerable complications. In one case in which 10 mg was injected into each foot, the average platinum concentration in resected pelvic lymph nodes was 0.83 microgram/gWet (maximum: 3.51 micrograms/gWet) even a week after treatment. Serum platinum was undetectable (< 50 ng/ml). These results suggest that a high concentration of carboplatin can be preserved for a long time by this novel interventional technique.


Asunto(s)
Carboplatino/administración & dosificación , Aceite Yodado/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Carboplatino/farmacocinética , Portadores de Fármacos , Emulsiones , Femenino , Humanos , Inyecciones , Ganglios Linfáticos/metabolismo , Metástasis Linfática , Masculino , Persona de Mediana Edad , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Neoplasias/patología
10.
Endocr J ; 40(2): 213-20, 1993 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7951507

RESUMEN

The effect of sustained stress on the plasma CRH level was studied in rats subjected to the stress of laparotomy conducted under ether anesthesia or water immersion-restraint. The role of AVP in ACTH secretion during such stress was also investigated. Concentrations of CRH and AVP in the hypothalamus, extrahypothalamic tissues and peripheral blood were measured by radioimmunoassays. Persistent secretion of ACTH was observed from 10 or 30 min to 120 min after the onset of each stress. Plasma CRH levels rose significantly 10 min after the onset of ether-laparotomy stress and remained significantly elevated at 120 min compared with controls. In the animals subjected to water immersion-restraint stress, plasma CRH tended to increase during the time course of the stress, reaching levels that were at least two times higher than the control. CRH concentrations in the median eminence (ME) during both types of stress decreased significantly at 120 min. In the ether-laparotomy stressed rats, CRH in the neurointermediate lobe (NIL) decreased significantly at 120 min, similar to the ME. Although a significant change in the adrenal CRH content was observed in the ether-laparotomy stressed rats, the involvement of adrenal CRH in ACTH secretion is unlikely as the absolute change in CRH was very small. These findings suggest that continuous CRH increase reflects a persistent secretion of CRH from the hypothalamic median eminence to the hypophysial portal vessels. It is possible that CRH secretion from the posterior pituitary gland is at least partly responsible for the persistent plasma ACTH increase in ether-laparotomy stress.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Anestesia por Inhalación , Hormona Liberadora de Corticotropina/metabolismo , Éter , Hipotálamo/metabolismo , Inmersión/efectos adversos , Laparotomía/efectos adversos , Estrés Psicológico/sangre , Hormona Adrenocorticotrópica/sangre , Animales , Arginina Vasopresina/metabolismo , Química Encefálica/fisiología , Hormona Liberadora de Corticotropina/sangre , Masculino , Eminencia Media/metabolismo , Hipófisis/metabolismo , Radioinmunoensayo , Ratas , Ratas Wistar
11.
Nihon Naibunpi Gakkai Zasshi ; 68(10): 1096-111, 1992 Oct 20.
Artículo en Japonés | MEDLINE | ID: mdl-1333997

RESUMEN

Two hundred and forty-one cases of isolated ACTH deficiency have been reported in Japan since 1969. Pituitary hormone responsiveness to stimulation tests before and after hydrocortisone supplementation was investigated in these cases. Plasma ACTH level showed no or little change in response to lysine vasopressin, metyrapone, CRF or insulin-induced hypoglycemia in 97.3-100% of the cases. Serum GH level changed little or not at all in response to GRF, insulin-induced hypoglycemia, glucagon, 1-dopa and arginine in 26.9, 29.3, 40.0, 50.0 and 56.1%, respectively. Serum TSH and prolactin (PRL) levels showed hyperresponse to TRH in 34.7 and 35.6%, respectively. After hydrocortisone therapy, GH secretion was more responsive than before therapy in 78.9% of the cases. After supplementation, TSH level was less responsive to TRH stimulation than before therapy in 59.3% of the cases. After hydrocortisone supplementation, TSH response to TRH decreased in 75% of ACTH-deficient patients without primary hypothyroidism but did not decrease in more than half of those with primary hypothyroidism. TSH response to TRH decreased after supplementation in 76.5% of the patients with TSH hyperresponsiveness before therapy, and increased after therapy in 66.7% of those with normal TSH responses before therapy. After supplementation, PRL response to TRH was less than that before therapy in 43.5% of ACTH--deficient patients, and greater than that before therapy in 30.4%. PRL response to TRH decreased after therapy in 66.7% of the patients with PRL hyperresponsiveness before therapy, and increased in 63.6% of those with normal PRL response before therapy. Primary hypothyroidism and Hashimoto's thyroiditis were complicated in 21.6 and 11.6%, respectively, of the 241 patients with isolated ACTH deficiency. In patients who had TSH hyperresponsiveness and/or high basal TSH levels and PRL hyperresponsiveness and/or high basal PRL levels, primary hypothyroidism was complicated in 58.4 and 42.3%, respectively. Hashimoto's thyroiditis was complicated in 29.8 and 20.5%, respectively, of these patients. Pituitary cell antibody (PCA) was detected in 36.6% of ACTH-deficient patients who were examined. Pituitary cell surface antibody (PCSA) to AtT-20 cells and GH3 cells was detected in 50.0 and 28.0% of the examined cases, respectively. The prevalence of PCA and PCSA did not differ between TSH-hyperresponsive patients and those with normal TSH basal levels and response, whereas PCA and PCSA were significantly more prevalent in PRL-hyperresponsive patients than in those with normal PRL levels and response. An empty sella was found in 30.2% of the examined case.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Hormona Adrenocorticotrópica/deficiencia , Hormona del Crecimiento/metabolismo , Prolactina/metabolismo , Tirotropina/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Hidrocortisona/uso terapéutico , Hipotiroidismo/complicaciones , Japón , Masculino , Persona de Mediana Edad , Pruebas de Función Hipofisaria , Pruebas de Función de la Tiroides , Hormona Liberadora de Tirotropina
12.
Jpn Heart J ; 31(3): 287-97, 1990 May.
Artículo en Inglés | MEDLINE | ID: mdl-2214132

RESUMEN

This study investigated the effects of a low dose of nisoldipine (5 mg, p.o.) in 10 patients with ischemic heart disease. The patients were subjected to a 90-min exercise regimen before and after a 5 mg dose of nisoldipine, using a supine bicycle ergometer adjusted to each patient's limitations. The mean blood plasma level of nisoldipine was 3.8 +/- 3.1 (SD) ng/ml. The drug significantly decreased the systolic arterial pressure in patients throughout the experimental session, whereas a change in the diastolic arterial pressure appeared only at the submaximal stage of the exercise. Additionally, at maximal exercise, nisoldipine caused a decrease in the mean coronary sinus pressure from 11.4 +/- 7 mmHg to 6.5 +/- 5 mmHg (p less than 0.01). By contrast, while at rest, nisoldipine decreased the coronary vascular resistance from 1.5 +/- 0.7 mmHg/ml/min to 1.0 +/- 0.7 mmHg/ml/min (p less than 0.05). After exercise, the drug decreased thromboxane B2 levels from 1133 +/- 907 pg/ml to 720 +/- 379 pg/ml (p less than 0.05) in the coronary sinus blood, and increased the 6 keto-prostaglandin F1 alpha levels from 465 +/- 135 pg/ml to 559 +/- 167 pg/ml (p less than 0.05) in brachial artery blood. This suggests that a low, oral dose of nisoldipine can moderately improve the systemic and coronary hemodynamics and afterloads, and may assist in improving the prostaglandin metabolism in ischemic heart disease patients.


Asunto(s)
Circulación Coronaria/efectos de los fármacos , Enfermedad Coronaria/tratamiento farmacológico , Hemodinámica/efectos de los fármacos , Nisoldipino/uso terapéutico , Prostaglandinas/metabolismo , 6-Cetoprostaglandina F1 alfa/sangre , Administración Oral , Adulto , Anciano , Presión Sanguínea/efectos de los fármacos , Enfermedad Coronaria/metabolismo , Enfermedad Coronaria/fisiopatología , Prueba de Esfuerzo , Humanos , Persona de Mediana Edad , Nisoldipino/administración & dosificación , Nisoldipino/sangre , Tromboxano B2/sangre , Resistencia Vascular/efectos de los fármacos
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