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1.
Phys Rev Lett ; 124(11): 112501, 2020 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-32242689

RESUMEN

The gyromagnetic factor of the low-lying E=251.96(9) keV isomeric state of the nucleus ^{99}Zr was measured using the time-dependent perturbed angular distribution technique. This level is assigned a spin and parity of J^{π}=7/2^{+}, with a half-life of T_{1/2}=336(5) ns. The isomer was produced and spin aligned via the abrasion-fission of a ^{238}U primary beam at RIKEN RIBF. A magnetic moment |µ|=2.31(14)µ_{N} was deduced showing that this isomer is not single particle in nature. A comparison of the experimental values with interacting boson-fermion model IBFM-1 results shows that this state is strongly mixed with a main νd_{5/2} composition. Furthermore, it was found that monopole single-particle evolution changes significantly with the appearance of collective modes, likely due to type-II shell evolution.

3.
Plant Biol (Stuttg) ; 25(5): 687-695, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37070345

RESUMEN

The reproductive characteristics of understory bamboo and the effects of dieback on overstory tree seedlings through temporal changes in the environment at the forest floor have only been examined in a few bamboo species, due to the unpredictable occurrence of flowering events and long intervals between them but provide valuable information on tree regeneration and succession in a forest with dense dwarf bamboo cover. We investigated environmental conditions and assessed seedlings (< 30-cm tall) of the dwarf bamboo Sasa borealis and overstory tree species at 44-50 measurement points during 2016-2021, which included a S. borealis mass flowering event in 2017. We also conducted seed germination tests to determine germination rates and patterns in S. borealis. Environmental factors affecting seedling recruitment of S. borealis and of overstory trees were analysed using spatiotemporal generalized linear mixed models in the Bayesian framework. We observed gradual temporal changes in the environment, including increasing canopy openness and decreasing maximum height of dead S. borealis culms. The seeds germinated slowly and the emergence of current-year S. borealis seedlings peaked in spring-summer in 2019. The tree seedling density after 2019 increased significantly compared to that before the dieback. The model results suggest that tree seedling establishment was enhanced by increased light availability. Continuous field observation beginning before S. borealis dieback revealed gradually enhanced tree recruitment in response to slow decay of the remaining dead culms and slow recovery of S. borealis. The seedling regeneration pattern of understory bamboo partly contributes to a prolonged opportunity for overstory tree regeneration.


Asunto(s)
Bosques , Plantones , Japón , Teorema de Bayes , Plantones/fisiología , Germinación , Ecosistema
4.
Phys Rev Lett ; 108(16): 162501, 2012 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-22680712

RESUMEN

We report on the spectroscopic quadrupole moment measurement of the 7/2(1)(-) isomeric state in (16)(43)S(27) [E*=320.5(5) keV, T(1/2)=415(3) ns], using the time dependent perturbed angular distribution technique at the RIKEN RIBF facility. Our value, |Q(s)|=23(3) efm(2), is larger than that expected for a single-particle state. Shell model calculations using the modern SDPF-U interaction for this mass region reproduce remarkably well the measured |Q(s)|, and show that non-negligible correlations drive the isomeric state away from a purely spherical shape.

5.
Diabet Med ; 29(4): 492-500, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21916970

RESUMEN

AIMS: Skin autofluorescence, a non-invasive measure of the accumulation for advanced glycation end products, has been reported to be a useful marker for diabetic vascular risks in the Caucasian population. The aim of this study was to evaluate associations between skin autofluorescence and vascular complications in non-Caucasian patients with Type 2 diabetes. METHODS: Subjects in this cross-sectional study comprised 130 Japanese patients with Type 2 diabetes. Skin advanced glycation end products were assessed by skin autofluorescence using an autofluorescence reader. Association between skin autofluorescence and severity of vascular complications was evaluated. RESULTS: Of the 130 patients, 60 (46.2%) had microvascular complications such as diabetic retinopathy, neuropathy and nephropathy, 10 (7.7%) had macrovascular complications and 63 (48.5%) had micro- and/or macrovascular complications. Skin autofluorescence increased with severity of vascular complications. Independent determinants of skin autofluorescence were age (ß = 0.24, P < 0.01), mean HbA(1c) in previous year (ß = 0.17, P = 0.03), microvascular complications (ß = 0.44, P < 0.01) and macrovascular complications (ß = 0.27, P < 0.01). Multiple logistic regression analysis revealed that diabetes duration (odds ratio 1.15, P < 0.01), systolic blood pressure (odds ratio 1.04, P = 0.01), skin autofluorescence (odds ratio 3.62, P = 0.01) and serum albumin (odds ratio 0.84, P < 0.01) were independent factors for the presence of vascular complications in these patients. CONCLUSIONS: Skin autofluorescence had independent effects on vascular complications in Japanese patients with Type 2 diabetes. This indicates that skin advanced glycation end products are a surrogate marker for vascular risk and a non-invasive autofluorescence reader may be a useful tool to detect high-risk cases in non-Caucasian patients with diabetes.


Asunto(s)
Enfermedades Cardiovasculares/etiología , Diabetes Mellitus Tipo 2/complicaciones , Fluorescencia , Productos Finales de Glicación Avanzada/metabolismo , Piel/metabolismo , Fumar/efectos adversos , Anciano , Pueblo Asiatico , Presión Sanguínea , Índice de Masa Corporal , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/metabolismo , Estudios Transversales , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/metabolismo , Angiopatías Diabéticas/epidemiología , Angiopatías Diabéticas/etiología , Angiopatías Diabéticas/metabolismo , Nefropatías Diabéticas/epidemiología , Nefropatías Diabéticas/etiología , Nefropatías Diabéticas/metabolismo , Neuropatías Diabéticas/epidemiología , Neuropatías Diabéticas/etiología , Neuropatías Diabéticas/metabolismo , Retinopatía Diabética/epidemiología , Retinopatía Diabética/etiología , Retinopatía Diabética/metabolismo , Femenino , Hemoglobina Glucada/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Factores de Riesgo
6.
Biochim Biophys Acta ; 1359(1): 71-9, 1997 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-9398087

RESUMEN

Differanisole A, 3,5-dichloro-2-hydroxy-4-methoxy-6-n-propylbenzoic acid, inhibited growth of human myeloid leukemia cells. The compound induced G1 arrest and granulocytic differentiation of HL-60 cells, although the differentiation-inducing effect was modest. Differanisole A and 9-cis retinoic acid (9cisRA) synergistically inhibited the growth and induced functional and morphologic differentiation of HL-60 and NB4 cells, whereas the combined treatment with differanisole A and all-trans retinoic acid or 1alpha,25-dihydroxyvitamin D3 was less effective. Similar results were obtained in primary culture of leukemia cells from a patient with acute promyelocytic leukemia. The synergistic effect on growth inhibition and induction of differentiation required simultaneous treatment with differanisole A and 9cisRA. Differanisole A and an RXR-specific ligand (Ro47-5944) cooperatively inhibited the cell growth, while the combined effect of differanisole A and an RAR-specific ligand Am80 was just additive. Differanisole A in combination with 9cisRA may have implications for therapy of acute promyelocytic leukemia patients.


Asunto(s)
Antibióticos Antineoplásicos/farmacología , Diferenciación Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Clorobenzoatos/farmacología , Leucemia Mieloide/patología , Tretinoina/farmacología , Alitretinoína , Calcitriol/farmacología , Citometría de Flujo , Granulocitos/citología , Granulocitos/efectos de los fármacos , Células HL-60 , Humanos , Ligandos , Receptores de Ácido Retinoico/metabolismo , Retinoides/farmacología , Sales de Tetrazolio/metabolismo , Activación Transcripcional/efectos de los fármacos , Células Tumorales Cultivadas
7.
Biochim Biophys Acta ; 676(3): 350-6, 1981 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-7284443

RESUMEN

A vegetalizing factor which induces the formation of endodermal and mesodermal organs in amphibian gastrula ectoderm was purified from chicken embryos. Preparative sodium dodecyl sulfate polyacrylamide electrophoresis and gel permeation chromatography on sephadex with different eluants were employed. In buffer containing 6 M urea the molecular weight of the factor was estimated to about 28 000-30 000. In buffer containing sodium dodecyl sulfate (SDS) the factor partially dissociates to smaller polypeptide chains. Because an equilibrium between molecules of different size is established, SDS-containing buffers are not suitable for preparative purposes. In 50%-70% formic acid the factor completely dissociates into smaller peptide chains (Mr about 13 000-15 000). Furthermore, very little absorption of the factor to the gel matrices or glass surfaces is observed in formic acid. The final purification can be achieved by high-performance gel permeation chromatography with glycerolpropyl-treated silica gel as column packing and 50% formic acid as eluant.


Asunto(s)
Formiatos , Sustancias de Crecimiento/aislamiento & purificación , Proteínas/aislamiento & purificación , Animales , Fenómenos Químicos , Química , Embrión de Pollo , Cromatografía en Gel , Electroforesis en Gel de Poliacrilamida , Endodermo/efectos de los fármacos , Sustancias de Crecimiento/farmacología , Mesodermo/efectos de los fármacos , Peso Molecular , Proteínas/farmacología , Dodecil Sulfato de Sodio , Triturus/embriología
8.
Clin Nephrol ; 63(2): 68-73, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15730047

RESUMEN

BACKGROUND AND AIM: Corticosteroid therapy is an effective way of treatment for many renal diseases, however, it is sometimes associated with infections. Our aim is to identify useful predictive markers of infection during steroid therapy. METHODS: We examined 121 patients (M/F = 71/50, mean age 43.8, range 15 - 82 years) who were treated with corticosteroids (IgA nephropathy in 51, minimal-change disease in 17, membranous nephropathy in 16 rapidly progressive glomerulonephritis (RPGN) in 13, lupus nephritis in 12 and other disorders in 12). Karnofsky's performance score (KPS) was employed to assess the physical functional status at the time of diagnosis. Infections were defined as conditions that required more than 1-week care, and those that caused the patient's death. RESULTS: Nineteen patients (15.7%) had infections during treatment. A logistic multivariate analysis showed significant correlations between infection and the use of immunosuppressive agents (relative risk RR = 7.7, p = 0.0265), ages of 52.9 years or more (RR = 13.5, p = 0.0026), initial number of lymphocytes (Lym) less than 1.250/microl (RR = 14.2, p = 0.0011), and KPS less than 77.4 (RR = 12.1, p = 0.0020). All correlations with infection were independent of all the other variables listed above. CONCLUSION: KPS, along with age, Lym and the use of immunosuppressive agents, are useful for the prediction of infectious complications during steroid therapy.


Asunto(s)
Actividades Cotidianas , Glucocorticoides/efectos adversos , Estado de Salud , Estado de Ejecución de Karnofsky , Enfermedades Renales/tratamiento farmacológico , Infecciones Oportunistas/etiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Quimioterapia Combinada , Femenino , Estudios de Seguimiento , Glucocorticoides/administración & dosificación , Humanos , Inmunosupresores/administración & dosificación , Inmunosupresores/efectos adversos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad
9.
J Clin Endocrinol Metab ; 80(2): 350-5, 1995 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7852489

RESUMEN

We reported that gestational thyrotoxicosis is induced by thyroid-stimulating activity (TSA) of circulating hCG. However, the serum immunological hCG concentration did not correlate to TSA. To elucidate this, we examined the relation of carbohydrate moieties of hCG to bioactivity in 79 early pregnant women, divided into 4 groups: no emesis, mild emesis, hyperemesis, and gestational thyrotoxicosis with hyperemesis. Serum free T4 (FT4) and free T3 (FT3) levels were significantly higher and TSH was lower in the hyperemesis (FT4, 23.42 +/- 5.02 pmol/L; FT3, 6.26 +/- 1.80 pmol/L; TSH, 0.30 +/- 0.44 mU/L) and in gestational thyrotoxicosis (FT4, 48.65 +/- 14.80 pmol/L; FT3, 14.71 +/- 3.47 pmol/L; TSH, < 0.04 mU/L) groups than in the no emesis group (FT4, 16.99 +/- 2.48 pmol/L; FT3, 5.51 +/- 0.75 pmol/L; TSH, 1.37 +/- 1.23 mU/L; P < 0.0005). TSA was also significantly higher in the hyperemesis (566 +/- 187%) and gestational thyrotoxicosis (832 +/- 168%) groups than in the no emesis group (321 +/- 135%). We found no significant difference among serum hCG concentrations measured by immunoassay in the four groups. To characterize the carbohydrate chains, serum hCG was fractionated by Concanavalin-A and ricin lectin affinity chromatography. The fraction firmly bound to Con-canavalin-A, which contains hCG with high mannose and hybrid-type carbohydrate chains, was significantly higher in the hyperemesis group (91.07 +/- 2.06%; n = 15) than in the no emesis group (89.61 +/- 2.38%; n = 24; P < 0.04). The fraction firmly bound to ricin column, which contains hCG with asialo-carbohydrate chains, was significantly increased in the gestational thyrotoxicosis group (3.44 +/- 1.70%; n = 5) compared with that in the no emesis group (1.77 +/- 0.49%; n = 24; P < 0.03). Serum FT4 positively correlated to the hCG fraction firmly bound to ricin column (r = 0.61; P < 0.001). We conclude that thyrotoxicosis with hyperemesis may be caused by circulating asialo-hCG with higher thyrotropic bioactivity.


Asunto(s)
Asialoglicoproteínas/fisiología , Gonadotropina Coriónica/fisiología , Complicaciones del Embarazo , Tirotoxicosis/etiología , Adulto , Gonadotropina Coriónica/sangre , Femenino , Humanos , Hiperemesis Gravídica/sangre , Hiperemesis Gravídica/etiología , Embarazo , Tirotoxicosis/sangre , Tirotropina/sangre , Tiroxina/sangre , Triyodotironina/sangre , Vómitos/sangre
10.
J Cereb Blood Flow Metab ; 20(3): 452-7, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10724108

RESUMEN

Thrombolytic stroke therapy with tissue plasminogen activator (tPA) remains complicated by serious risks of cerebral hemorrhage and brain injury. In this study, a novel model of tPA-induced hemorrhage was used in spontaneously hypertensive rats to examine the correlates of hemorrhage, and test methods of reducing hemorrhage and brain injury. Homologous blood clot emboli were used to occlude the middle cerebral artery in spontaneously hypertensive rats, and delayed administration of tPA (6 hours postischemia) resulted in high rates of cerebral hemorrhage 24 hours later. Compared with untreated rats, tPA significantly increased hemorrhage volumes by almost 85%. Concomitantly, infarction and neurological deficits were worsened by tPA. A parallel experiment in normotensive Wistar-Kyoto rats showed markedly reduced rates of hemorrhage, and tPA did not significantly increase hemorrhage volumes. To examine whether tPA-induced hemorrhage was caused by the delayed onset of reperfusion per se, another group of spontaneously hypertensive rats was subjected to focal ischemia using a mechanical method of arterial occlusion. Delayed (6 hours) reperfusion via mechanical means did not induce hemorrhage. However, administration of tPA plus delayed mechanical reperfusion significantly increased hemorrhage volumes. Since reperfusion injury was implicated, a final experiment compared outcomes in spontaneously hypertensive rats treated with tPA plus the free radical spin trap alpha-phenyl tert butyl nitrone (alpha-PBN) versus tPA alone. tPA-induced hemorrhage volumes were reduced by 40% with alpha-PBN, and infarction and neurological deficits were also decreased. These results indicate that (1) blood pressure is an important correlate of tPA-induced hemorrhage, (2) tPA interacts negatively with reperfusion injury to promote hemorrhage, and (3) combination therapies with anti-free radical treatments may reduce the severity of tPA-induced hemorrhage and brain injury after cerebral ischemia.


Asunto(s)
Isquemia Encefálica/terapia , Encéfalo/patología , Hemorragia Cerebral/inducido químicamente , Embolia Intracraneal/terapia , Activadores Plasminogénicos/efectos adversos , Detección de Spin , Activador de Tejido Plasminógeno/efectos adversos , Animales , Isquemia Encefálica/tratamiento farmacológico , Hemorragia Cerebral/complicaciones , Hemorragia Cerebral/etiología , Óxidos N-Cíclicos , Quimioterapia Combinada , Radicales Libres , Hipertensión/complicaciones , Embolia Intracraneal/tratamiento farmacológico , Masculino , Óxidos de Nitrógeno/uso terapéutico , Activadores Plasminogénicos/uso terapéutico , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas WKY , Daño por Reperfusión/complicaciones , Activador de Tejido Plasminógeno/uso terapéutico
11.
J Cereb Blood Flow Metab ; 20(2): 396-404, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10698078

RESUMEN

The overall hypothesis that cell death after intracerebral hemorrhage is mediated in part by apoptotic mechanisms was tested. Intracerebral hemorrhage was induced in rats using stereotactic infusions of 0.5 U of collagenase (1-microL volume) into the striatum. After 24 hours, large numbers of TUNEL-positive stained cells with morphologies suggestive of apoptosis were present in the center and periphery of the hemorrhage. Double staining with Nissl and immunocytochemical labeling with antibodies against neuronal nuclei and glial fibrillary acidic protein suggested that these TUNEL-positive cells were mostly neurons and astrocytes. Electrophoresis of hemorrhagic brain extracts showed evidence of DNA laddering into approximately 200-bp fragments. Western blots showed cleavage of the cytosolic caspase substrate gelsolin. The density of TUNEL-positive cells at 24 and 48 hours after hemorrhage was significantly reduced by treatment with the broad-spectrum caspase inhibitor zVADfmk. It was unlikely that apoptotic changes were due to neurotoxicity of injected collagenase because TUNEL-positive cells and DNA laddering were also obtained in an alternative model of hemorrhage where autologous blood was infused into the striatum. Furthermore, equivalent doses of collagenase did not induce cell death in primary neuronal cultures. These results provide initial evidence that apoptotic mechanisms may mediate some of the injury in brain after intracerebral hemorrhage.


Asunto(s)
Apoptosis , Hemorragia de los Ganglios Basales/patología , Ganglios Basales/irrigación sanguínea , Ganglios Basales/patología , Clorometilcetonas de Aminoácidos/farmacología , Animales , Astrocitos/química , Ganglios Basales/enzimología , Hemorragia de los Ganglios Basales/metabolismo , Caspasas/análisis , Caspasas/metabolismo , Recuento de Células , Células Cultivadas , Colagenasas/metabolismo , ADN/análisis , Gelsolina/análisis , Gelsolina/metabolismo , Proteína Ácida Fibrilar de la Glía/análisis , Etiquetado Corte-Fin in Situ , Masculino , Neuronas/citología , Neuronas/efectos de los fármacos , Neuronas/enzimología , Fármacos Neuroprotectores/farmacología , Ratas , Ratas Sprague-Dawley
12.
J Cereb Blood Flow Metab ; 19(12): 1316-21, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10598935

RESUMEN

Tissue type plasminogen activator (tPA) can be effective therapy for embolic stroke by restoring cerebral perfusion. However, a recent experimental study showed that tPA increased infarct size in a mouse model of transient focal ischemia, suggesting a possible adverse effect of tPA on ischemic tissue per se. In this report, the effects of tPA in two rat models of cerebral ischemia were compared. In experiment 1, rats were subjected to focal ischemia via injection of autologous clots into the middle cerebral artery territory. Two hours after clot injection, rats were treated with 10 mg/kg tPA or normal saline. Perfusion-sensitive computed tomography scanning showed that tPA restored cerebral perfusion in this thromboembolic model. Treatment with tPA significantly reduced ischemic lesion volumes measured at 24 hours by >60%. In experiment 2, three groups of rats were subjected to focal ischemia via a mechanical approach in which a silicon-coated filament was used intraluminally to occlude the origin of the middle cerebral artery. In two groups, the filament was withdrawn after 2 hours to allow for reperfusion, and then rats were randomly treated with 10 mg/kg tPA or normal saline. In the third group, rats were not treated and the filament was not withdrawn so that permanent focal ischemia was present. In this experiment, tPA did not significantly alter lesion volumes after 2 hours of transient focal ischemia. In contrast, permanent ischemia significantly increased lesion volumes by 55% compared with transient ischemia. These results indicate that in these rat models of focal cerebral ischemia, tPA did not have detectable negative effects. Other potentially negative effects of tPA may be dependent on choice of animal species and model systems.


Asunto(s)
Ataque Isquémico Transitorio/tratamiento farmacológico , Activador de Tejido Plasminógeno/toxicidad , Activador de Tejido Plasminógeno/uso terapéutico , Animales , Traumatismos de las Arterias Carótidas , Arteria Carótida Externa , Modelos Animales de Enfermedad , Fibrinolíticos/uso terapéutico , Fibrinolíticos/toxicidad , Embolia Intracraneal , Masculino , Ratones , Arteria Cerebral Media , Ratas , Ratas Sprague-Dawley
13.
J Cereb Blood Flow Metab ; 20(12): 1681-9, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11129784

RESUMEN

It has been shown recently that matrix metalloproteinases (MMPs) are elevated after cerebral ischemia. In the current study, we investigated the pathophysiologic role for MMP-9 (gelatinase B, EC.3.4.24.35) in a mouse model of permanent focal cerebral ischemia, using a combination of genetic and pharmacologic approaches. Zymography and Western blot analysis demonstrated that MMP-9 protein levels were rapidly up-regulated in brain after ischemic onset. Reverse transcription polymerase chain reaction showed increased transcription of MMP-9. There were no differences in systemic hemodynamic parameters and gross cerebrovascular anatomy between wild type mice and mutant mice with a targeted knockout of the MMP-9 gene. After induction of focal ischemia, similar reductions in cerebral blood flow were obtained. In the MMP-9 knockout mice, ischemic lesion volumes were significantly reduced compared with wild type littermates in male and female mice. In normal wild type mice, the broad spectrum MMP inhibitor BB-94 (batimastat) also significantly reduced ischemic lesion size. However, BB-94 had no detectable protective effect when administered to MMP-9 knockout mice subjected to focal cerebral ischemia. These data demonstrate that MMP-9 plays a deleterious role in the development of brain injury after focal ischemia.


Asunto(s)
Isquemia Encefálica/metabolismo , Metaloproteinasa 9 de la Matriz/genética , Metaloproteinasa 9 de la Matriz/metabolismo , Fenilalanina/análogos & derivados , Fenilalanina/farmacología , Inhibidores de Proteasas/farmacología , Tiofenos/farmacología , Animales , Encéfalo/irrigación sanguínea , Encéfalo/enzimología , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/patología , Masculino , Inhibidores de la Metaloproteinasa de la Matriz , Ratones , Ratones Endogámicos , Ratones Noqueados , Fármacos Neuroprotectores/farmacología , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/metabolismo , Accidente Cerebrovascular/patología , Transcripción Genética/efectos de los fármacos , Transcripción Genética/fisiología
14.
FEBS Lett ; 165(2): 277-9, 1984 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-6581988

RESUMEN

Butylated hydroxytoluene (BHT) which is widely used as an anti-oxidant in food has been found to induce the differentiation of murine erythroleukemia cells. BHT also amplifies the differentiation inducing activity of DMSO.


Asunto(s)
Hidroxitolueno Butilado/farmacología , Leucemia Eritroblástica Aguda/patología , Leucemia Experimental/patología , Animales , Diferenciación Celular/efectos de los fármacos , Línea Celular , Dimetilsulfóxido/farmacología , Sinergismo Farmacológico , Cinética , Ratones
15.
FEBS Lett ; 322(1): 73-5, 1993 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-8387029

RESUMEN

Differanisole A isolated from the conditioned medium of a soil microorganism, Chaetomium strain RB-001, is an inducer of the differentiation of the Friend leukemic cells (mouse leukemia cells). The chemical structure of this substance is very similar to that of stalk cell differentiation-inducing factor (DIF) isolated from the cellular slime mould, Dictyostelium discoideum. We examined the effects of differanisole A on Dictyostelium HM44 cells, a mutant strain which is defective in DIF production, and found this substance to be an inducer of stalk cell differentiation in D. discoideum.


Asunto(s)
Clorobenzoatos/farmacología , Dictyostelium/efectos de los fármacos , Animales , Diferenciación Celular/efectos de los fármacos , Clorobenzoatos/química , AMP Cíclico/farmacología , Dictyostelium/citología , Hexanonas/química , Hexanonas/farmacología , Leucemia Eritroblástica Aguda , Ratones , Estructura Molecular , Células Tumorales Cultivadas
16.
FEBS Lett ; 445(1): 202-6, 1999 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-10069401

RESUMEN

We have pursued the hypothesis that the carbonyl modification of proteins by glycoxidation and lipoxidation reactions plays a role in atherogenesis. Human atherosclerotic tissues with fatty streaks and uremic arteriosclerotic tissues were examined, with specific antibodies, to detect protein adducts formed with carbonyl compounds by glycoxidation or lipoxidation reactions, i.e. advanced glycation end products (AGEs) or glycoxidation products, such as carboxymethyllysine (CML) and pentosidine, and lipoxidation products, such as malondialdehyde (MDA)-lysine and 4-hydroxy-nonenal (HNE)-protein adduct. All the four adducts were identified in the proliferative intima and in macrophage-rich fatty streaks. If the carbonyl modification is not a mere result but is a contributor to atherogenesis, inhibition of glycoxidation and lipoxidation reactions might prevent vascular tissue damage. We tested this hypothesis in rats following balloon injury of their carotid arteries, a model exhibiting a remarkable intimal thickening, which are stained positive for all the four adducts. Oral administration of 2-isopropylidenehydrazono-4-oxo-thiazolidin-5-ylacetanili de (OPB-9195), an inhibitor of both glycoxidation and lipoxidation reactions, in rats following balloon injury effectively prevented the intimal thickening. These data suggest a role for the carbonyl modification of proteins by glycoxidation and lipoxidation reactions in most, if not all, types of vascular tissue damage ('carbonyl stress'), and the usefulness of inhibitors of carbonyl reactions for the treatment of vascular tissue damage.


Asunto(s)
Arterias Carótidas/patología , Tiadiazoles/farmacología , Anciano , Anciano de 80 o más Años , Animales , Arteriosclerosis/patología , Arterias Carótidas/efectos de los fármacos , Cateterismo , Enfermedad de la Arteria Coronaria/patología , Femenino , Glicosilación , Humanos , Técnicas para Inmunoenzimas , Metabolismo de los Lípidos , Masculino , Persona de Mediana Edad , Oxidación-Reducción , Ratas , Ratas Sprague-Dawley , Tiazolidinas
17.
FEBS Lett ; 437(1-2): 24-8, 1998 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-9804165

RESUMEN

Accumulation of carbonyl derivatives of proteins (protein carbonyl) is taken as a biomarker of oxidative protein damage in aging and in various diseases. We detected protein carbonyls in situ in human diabetic arteriosclerotic tissues and characterized the formation of protein carbonyls. Protein carbonyls were identified in the thickened intima of arterial walls and co-localized with protein adducts formed by carbonyl amine chemistry between protein and carbonyl compounds derived from autoxidation of carbohydrates, lipids, and ascorbate, i.e. advanced glycation end products or glycoxidation products, such as carboxymethyllysine (CML) and pentosidine, and lipoxidation products, such as malondialdehyde (MDA) and 4-hydroxy-nonenal (HNE). In vitro incubation of proteins with ascorbic acid accelerated the production of protein carbonyls as well as CML and pentosidine, and incubation with arachidonate accelerated the production of protein carbonyls as well as CML, MDA, and HNE. By contrast, incubation of proteins with glucose resulted in the production of CML and pentosidine, but not protein carbonyls. Schiff base inhibitors, (+/-)-2-isopropylidenehydrazono-4-oxo-thiazolidin-5-ylace tanilide and aminoguanidine, inhibited the production of protein carbonyls after incubation with ascorbate and arachidonate. The present study suggests that ascorbate and polyunsaturated fatty acids, but not glucose, represent potential sources of protein carbonyls, and that both the glycoxidation and lipoxidation reactions contribute to protein carbonyl formation in aging and various diseases.


Asunto(s)
Arteriosclerosis/metabolismo , Angiopatías Diabéticas/metabolismo , Productos Finales de Glicación Avanzada/metabolismo , Ácido Araquidónico/farmacología , Arginina/análogos & derivados , Arginina/análisis , Ácido Ascórbico/farmacología , Glucosa/farmacología , Glicosilación , Humanos , Peroxidación de Lípido , Lipoproteínas/metabolismo , Lisina/análogos & derivados , Lisina/análisis , Malondialdehído/análisis , Oxidación-Reducción , Estrés Oxidativo
18.
J Dermatol Sci ; 20(1): 72-8, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-10342750

RESUMEN

Skin hyperpigmentation and itching are characteristic findings in systemic sclerosis (SSC) patients. Stem cell factor (SCF, c-kit ligand) is a multifunctional cytokine which can promote melanocyte and mast cell development. We investigated the SCF expression histopathologically in normal and SSC skin, and compared the expression with the serum SCF levels measured with a specific enzyme-linked immunosorbent assay. The epidermal and dermal immunoreactive SCF expression was markedly higher in the forearm skin of edematous phase SSC patients than in that of normal subjects. Tissue SCF expression declined from the sclerotic phase to the atrophic phase, where it was close to the normal level. In contrast, the elevated serum SCF level seen in the edematous phase samples was further increased in the sclerotic phase samples. The serum SCF level decreased in the atrophic phase, but it still remained at a level higher than that of the normal controls. Itching and increase of dermal mast cell number are characteristic of edematous phase SSC, and are in bears a parallel to the presently observed dermal SCF expression profile. Pigmentation is significant in sclerotic phase SSC and lasts to the atrophic phase, which may correspond to the serum SCF level observed here. These results indicate a contribution of the fibroblast membrane integral SCF in dermal mast cell development, and of the soluble serum SCF to melanocyte activation in SSC.


Asunto(s)
Esclerodermia Sistémica/metabolismo , Piel/metabolismo , Factor de Células Madre/biosíntesis , Factor de Células Madre/sangre , Adulto , Anciano , Western Blotting , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Valores de Referencia , Esclerodermia Sistémica/sangre , Esclerodermia Sistémica/inmunología , Piel/inmunología , Factor de Células Madre/inmunología
19.
J Dermatol Sci ; 21(1): 49-58, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10468192

RESUMEN

Caspase-1 (CASP1) interleukin-1beta (IL-1beta) converting enzyme (ICE) has been cloned as a specific enzyme which activates the biologically inactive pro-form of IL-1beta into biological active IL-1beta. Based on the significant homology to Ced-3, Caenorhabditis elegans apoptotic gene and, proof of apoptotic activity of ICE in rat fibroblasts, ICE was renamed as CASP1. In contrast to in vitro functions, the in vivo significance of high expression of CASP1 in skin remains to be elucidated. We transferred plasmid DNA encoding murine CASP1 with beta-actin promoter into mouse skin. The CASP1 DNA-injected skin, but not skin injected with control plasmid without CASP1, developed localized erythema with subcutaneous nodules. The nodules were associated with marked inflammatory infiltrates. The apoptotic cells detected by the TUNEL method were distributed in and around the inflammatory foci. The plasma IL-1beta level of CASP1 DNA-injected mouse was elevated compared with that of the control DNA-injected mouse. These inflammatory reactions of CASP1 DNA-injected skin were suppressed by treatment with neutralizing anti-murine IL-1beta antibodies, but the TUNEL positive apoptotic cells were still detected. This study clearly demonstrate dual roles of CASP1 in causing IL-1beta associated granulomatous skin infiltration and inducing apoptotic cell death in vivo.


Asunto(s)
Apoptosis , Caspasa 1/administración & dosificación , Caspasa 1/genética , ADN/administración & dosificación , Dermatitis por Contacto/enzimología , Dermatitis por Contacto/etiología , Interleucina-1/fisiología , Animales , Anticuerpos/farmacología , Apoptosis/genética , Caspasa 1/fisiología , Dermatitis por Contacto/genética , Dermatitis por Contacto/patología , Femenino , Inyecciones Intradérmicas , Interleucina-1/biosíntesis , Interleucina-1/inmunología , Operón Lac , Ratones , Ratones Pelados , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transfección
20.
Surgery ; 109(3 Pt 1): 277-83, 1991 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2000559

RESUMEN

This study was designed to clarify the effect of hyperdynamic circulatory support with dobutamine or dopamine after massive hepatectomy on hepatic hemodynamics, oxygen supply and demand, and lactate uptake. Mongrel dogs were allocated three groups: 70% hepatectomy group; a group that received dobutamine after 70% hepatectomy; and a group that received dopamine after 70% hepatectomy. Hepatic blood flow and oxygen delivery to the liver decreased after 70% hepatectomy. Although oxygen consumption in the liver also decreased, oxygen consumption per liver weight increased after massive hepatectomy; an increase of oxygen uptake ratio and a decrease of lactate uptake in the liver were observed. When dobutamine or dopamine were administered after 70% hepatectomy, hepatic blood flow increased, followed by normalization of the balance of oxygen supply and demand in the liver; lactate uptake subsequently improved in the liver. The data support the conclusion that hepatic oxygen consumption affected by dopamine and dobutamine is associated with an increase in the extraction of lactate. Hyperdynamic hepatic circulatory support was advantageous to hemodynamics and metabolism in the residual liver after massive hepatectomy.


Asunto(s)
Hemodinámica , Hepatectomía , Circulación Hepática , Hígado/fisiología , Animales , Dobutamina/farmacología , Perros , Lactatos/metabolismo , Hígado/efectos de los fármacos , Circulación Hepática/efectos de los fármacos , Oxígeno/sangre , Consumo de Oxígeno/efectos de los fármacos , Presión Parcial , Valores de Referencia , Flujo Sanguíneo Regional/efectos de los fármacos
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