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1.
J Chem Phys ; 160(6)2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38341782

RESUMEN

Poly(ethylene oxide) (PEO) is a well-known biocompatible polymer and has widely been used for medical applications. Recently, we have investigated the dynamic behavior of hydration water in the vicinity of PEO chains at physiological temperature and shown the presence of slow water with diffusion coefficient one order of magnitude less than that of bulk water. This could be evidence for the intermediate water that is critical for biocompatibility; however, its detailed dynamical features were not established. In this article, we analyze the quasi-elastic neutron scattering from hydration water through mode distribution analysis and present a microscopic picture of hydration water as well as its relation to cold crystallization.

2.
Biochim Biophys Acta Gen Subj ; 1861(1 Pt B): 3651-3660, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27156489

RESUMEN

J-PARC, Japan Proton Accelerator Research Complex provides short pulse proton beam at a repetition rate 25Hz and the maximum power is expected to be 1MW. Materials and Life Science Experimental Facility (MLF) has 23 neutron beam ports and 21 instruments have already been operated or under construction/commissioning. There are 6 inelastic/quasi-elastic neutron scattering spectrometers and the complementary use of these spectrometers will open new insight for life science. This article is part of a Special Issue entitled "Science for Life" Guest Editor: Dr. Austen Angell, Dr. Salvatore Magazù and Dr. Federica Migliardo.


Asunto(s)
Elasticidad , Difracción de Neutrones/instrumentación , Análisis Espectral/instrumentación , ADN/química , Japón , Membrana Dobles de Lípidos/química , Fonones , Protones , Agua/química
3.
J Chem Phys ; 147(3): 034905, 2017 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-28734290

RESUMEN

Shear-induced multilamellar vesicle (MLV) formation has been studied by coupling the small-angle neutron scattering (SANS) technique with neutron spin echo (NSE) spectroscopy. A 10% mass fraction of the nonionic surfactant pentaethylene glycol dodecyl ether (C12E5) in water was selected as a model system for studying weak inter-lamellar interactions. These interactions are controlled either by adding an anionic surfactant, sodium dodecyl sulfate, or an antagonistic salt, rubidium tetraphenylborate. Increasing the charge density in the bilayer induces an enhanced ordering of the lamellar structure. The charge density dependence of the membrane bending modulus was determined by NSE and showed an increasing trend with charge. This behavior is well explained by a classical theoretical model. By considering the Caillé parameters calculated from the SANS data, the layer compressibility modulus B¯ is estimated and the nature of the dominant inter-lamellar interaction is determined. Shear flow induces MLV formation around a shear rate of 10 s-1, when a small amount of charge is included in the membrane. The flow-induced layer undulations are in-phase between neighboring layers when the inter-lamellar interaction is sufficiently strong. Under these conditions, MLV formation can occur without significantly changing the inter-lamellar spacing. On the other hand, in the case of weak inter-lamellar interactions, the flow-induced undulations are not in-phase, and greater steric repulsion leads to an increase in the inter-lamellar spacing with shear rate. In this case, MLV formation occurs as the amplitude of the undulations gets larger and the steric interaction leads to in-phase undulations between neighboring membranes.

4.
Br J Dermatol ; 170(4): 922-9, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24329764

RESUMEN

BACKGROUND: Current treatment with biologics has produced dramatic therapeutic effects in patients with psoriasis, although these agents occasionally decrease in efficacy. One of the main factors responsible for this attenuation is attributed to the development of antidrug antibodies (ADAs). OBJECTIVES: To analyse the relationship between serum drug concentrations, the presence of ADAs and treatment efficacy of adalimumab and infliximab, and to determine the optimal use of these biologics. METHODS: This was a 1-year prospective study in the dermatology departments of Kobe University Hospital and collaborating hospitals. All patients starting a regimen of adalimumab and infliximab for psoriasis were included. We measured the serum concentration of the drugs and titres of antibodies to adalimumab and infliximab, as well as the Psoriasis Area and Severity Index scores at weeks 0, 4, 12, 24 and 48 during the first year of treatment. RESULTS: We observed a 50% positive rate of ADAs to adalimumab, and a 41% positive rate of ADAs to infliximab. The titres of ADAs showed a wide range from low to high titres. In the high-titre groups, the patients exhibited a decreased clinical response, and demonstrated a negative correlation between titre and clinical response. However, an equivalent therapeutic effect was observed between the low-titre group and the group with no antibodies detected for adalimumab. For infliximab, the patients with ADAs showed decreased clinical response. An apparent negative correlation between antibody production and reduced clinical response was observed. CONCLUSIONS: Two biologics, adalimumab and infliximab, showed different therapeutic behaviour. The measurement of ADAs and drug concentrations has important implications for treatment with biologics.


Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Neutralizantes/fisiología , Fármacos Dermatológicos/uso terapéutico , Psoriasis/tratamiento farmacológico , Adalimumab , Anticuerpos Monoclonales/sangre , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales Humanizados/sangre , Anticuerpos Monoclonales Humanizados/inmunología , Formación de Anticuerpos/efectos de los fármacos , Factores Biológicos/uso terapéutico , Fármacos Dermatológicos/sangre , Fármacos Dermatológicos/inmunología , Femenino , Humanos , Infliximab , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Psoriasis/inmunología , Resultado del Tratamiento
5.
J Periodontal Res ; 46(6): 655-62, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21722135

RESUMEN

BACKGROUND AND OBJECTIVE: Periodontitis is characterized by periodontal tissue inflammation and alveolar bone loss. The intermittent administration of parathyroid hormone (PTH), a major regulator of bone remodeling, has been demonstrated to stimulate osteoblastic activity. Although the systemic administration of PTH has been reported to protect against periodontitis-associated bone loss, the effect of the topical administration of PTH is unclear. In this study, the effect of intermittent administration of PTH on osteoblastic differentiation was examined in cultured calvaria cells and then the effect of topical and intermittent administration of PTH was determined by measuring the recovery of alveolar bone loss after inducing experimental periodontitis in rats. MATERIAL AND METHODS: Alkaline phosphatase activity and bone nodule formation were measured in fetal rat calvaria cells. Experimental periodontitis was induced by placing nylon ligature around rat maxillary molars for 20 d. After ligature removal (day 0), PTH was topically injected into buccal gingiva three times a week for 10 wk. Micro-computed tomography analysis and histological examination were performed on days 35 and 70. RESULTS: Intermittent exposure of PTH in calvaria cells increased alkaline phosphatase activity and bone nodule formation by 1.4- and 2.4-fold, respectively. Ligature procedures induced marked alveolar bone loss around the molars on day 0 and greater bone recovery was observed in the PTH-treated rats on day 70. An increase in osteoid formation on the surface of alveolar bone was detected in the PTH-treated rats. CONCLUSION: Intermittent treatment with PTH stimulated osteoblastic differentiation in fetal rat calvaria cell cultures, and topical and intermittent administration of PTH recovered alveolar bone loss in rat experimental periodontitis.


Asunto(s)
Pérdida de Hueso Alveolar/tratamiento farmacológico , Regeneración Ósea/efectos de los fármacos , Osteoblastos/efectos de los fármacos , Hormona Paratiroidea/administración & dosificación , Periodontitis/tratamiento farmacológico , Administración Tópica , Fosfatasa Alcalina/biosíntesis , Pérdida de Hueso Alveolar/diagnóstico por imagen , Animales , Diferenciación Celular/efectos de los fármacos , Células Cultivadas , Esquema de Medicación , Feto , Procesamiento de Imagen Asistido por Computador , Ligadura , Osteoblastos/citología , Osteoblastos/metabolismo , Ratas , Ratas Endogámicas F344 , Ratas Wistar , Cráneo/citología , Microtomografía por Rayos X
6.
Appl Radiat Isot ; 164: 109106, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32819495

RESUMEN

Boron Neutron Capture Therapy (BNCT) is a radiotherapy for the treatment of intractable cancer. In BNCT precise determination of 10B concentration in whole blood sample before neutron irradiation of the patient, as well as accurate neutron dosimetry, is crucial for control of the neutron irradiation time. For this purpose ICP-AES and neutron induced prompt γ-ray analysis are generally used. In Ibaraki Neutron Medical Research Center (iNMRC), an intense proton beam will be accelerated up to 8 MeV, which can also be used for Charged Particle Activation Analysis (CPAA). Thus, in this study, we apply the CPAA utilizing the proton beam to non-destructive and accurate determination of 10B concentration in whole blood sample. A CPAA experiment is performed by utilizing an 8 MeV proton beam from the tandem accelerator of Nuclear Science Research Institute in Japan Atomic Energy Agency. The 478 keV γ-ray of 7Be produced by the 10B(p, α)7Be reaction is used to quantify the 10B in human blood. The 478 keV γ-ray intensity is normalized by the intensities of the 847 keV and 1238 keV γ-rays of 56Co originating from Fe in blood. The normalization methods were found to be linear in the range of 3.27 µg 10B/g to 322 µg 10B/g with correlation coefficients of better than 0.9999.


Asunto(s)
Boro/sangre , Boro/normas , Terapia por Captura de Neutrón de Boro/métodos , Calibración , Rayos gamma , Humanos , Espectrometría de Masas/métodos , Radiometría/métodos , Dosificación Radioterapéutica , Estándares de Referencia , Reproducibilidad de los Resultados , Incertidumbre
7.
Science ; 270(5244): 1988-92, 1995 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-8533090

RESUMEN

A complementary DNA encoding a mitogen-activated protein (MAP) kinase homolog has been isolated from tobacco plants. Transcripts of the corresponding gene were not observed in healthy tobacco leaves but began to accumulate 1 minute after mechanical wounding. In tobacco plants transformed with the cloned complementary DNA, trans inactivation of the endogenous homologous gene occurred, and both production of wound-induced jasmonic acid and accumulation of wound-inducible gene transcripts were inhibited. In contrast, the levels of salicylic acid and transcripts for pathogen-inducible, acidic pathogenesis-related proteins were increased upon wounding. These results indicate that this MAP kinase is part of the initial response of higher plants to mechanical wounding.


Asunto(s)
Proteínas Quinasas Dependientes de Calcio-Calmodulina/genética , Genes de Plantas , Nicotiana/enzimología , Plantas Tóxicas , Transducción de Señal , Secuencia de Aminoácidos , Proteínas Quinasas Dependientes de Calcio-Calmodulina/química , Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , Ciclopentanos/metabolismo , ADN Complementario/genética , Datos de Secuencia Molecular , Oxilipinas , Fosfolipasas A/metabolismo , Fosforilación , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Salicilatos/metabolismo , Ácido Salicílico , Nicotiana/genética
8.
J Periodontal Res ; 43(3): 261-7, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18447852

RESUMEN

BACKGROUND AND OBJECTIVE: Simvastatin, a cholesterol-lowering drug, has been reported to show anabolic effects on bone metabolism. We examined the effects of simvastatin in vitro using cultured rat calvaria cells and in vivo using periodontitis-induced rats. MATERIAL AND METHODS: Alkaline phosphatase activity and bone nodule formation were measured in cultured rat calvaria cells. Nylon ligature was placed around the maxillary molars of Fischer male rats for 20 d to induce alveolar bone resorption. After ligature removal, simvastatin was topically injected into the buccal gingivae for 70 d and then microcomputed tomography and histological examinations were performed. RESULTS: Simvastatin maintained high alkaline phosphatase activity and increased bone nodule formation in rat calvaria cells in a dose-dependent manner, showing that simvastatin increased and maintained a high level of osteoblastic function. Microcomputed tomography images revealed that treatment with simvastatin recovered the ligature-induced alveolar bone resorption, showing a 46% reversal of bone height. Histological examination clarified that low-mineralized alveolar bone was formed in simvastatin-treated rats. CONCLUSION: These findings demonstrate that simvastatin has the potential to stimulate osteoblastic function and that topical administration of simvastatin may be effective for the recovery of alveolar bone loss in rats.


Asunto(s)
Pérdida de Hueso Alveolar/tratamiento farmacológico , Regeneración Ósea/efectos de los fármacos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Osteoblastos/efectos de los fármacos , Periodontitis/tratamiento farmacológico , Simvastatina/uso terapéutico , Administración Tópica , Fosfatasa Alcalina/biosíntesis , Animales , Células Cultivadas , Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Masculino , Ratas , Ratas Endogámicas F344 , Simvastatina/administración & dosificación , Simvastatina/farmacología , Cráneo , Tomografía
9.
Maturitas ; 58(1): 59-69, 2007 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-17658706

RESUMEN

OBJECTIVE: Increasing research suggested that Cimicifugae rhizoma might be protective against osteoporosis. In this study, we investigated the effects of three cycloartane-type triterpenoids isolated from Cimicifugae rhizoma, cimicidol-3-O-beta-D-xyloside (1), cimicidanol-3-O-beta-D-xyloside (2) and acetylacteol-3-O-beta-d-xyloside (3) on bone resorption in vitro and bone loss in ovariectomized (OVX) mice. METHODS: The activities of the tested compounds on bone resorption were evaluated using three assays, neonatal mouse parietal bone organ culture, osteoclast-like cells (OCLs) formation and pit formation. The effects on bone mineral density (BMD) and uterine weight were examined using OVX mice. Using LC-MS/MS method, the serum concentrations of the triterpenoids were measured in mice serum collected at 0.5, 1, 3, 6 and 12h following its oral administration. RESULTS: All of the tested compounds exerted the inhibitory effects on bone resorption in bone organ culture, suppressed both of the formation and the resorbing activity of OCLs. Furthermore, a synergistic effect was observed among those compounds. In vivo studies revealed that compounds 1-3 and the mixture of compounds 1-3 prevented the bone loss in OVX mice without affecting uterine weight, and each compound was detected in the mice serum after single oral administration. CONCLUSIONS: The triterpenoids exerted the inhibitory effects on osteoclastic bone resorption through the suppression of both OCLs formation and the resorbing activity of OCLs, and also showed a significant protective effect on BMD in OVX mice. The present results might provide a new pharmacological potential for the treatment of osteoporosis.


Asunto(s)
Resorción Ósea/tratamiento farmacológico , Cimicifuga/química , Medicamentos Herbarios Chinos/farmacología , Osteoclastos/efectos de los fármacos , Osteoporosis/tratamiento farmacológico , Ovariectomía/efectos adversos , Fitoterapia , Animales , Índice de Masa Corporal , Resorción Ósea/etiología , Cimicifuga/clasificación , Medicamentos Herbarios Chinos/química , Femenino , Ratones , Osteoporosis/etiología , Osteoporosis/prevención & control , Fitoterapia/métodos , Relación Estructura-Actividad , Resultado del Tratamiento , Triterpenos/química , Triterpenos/aislamiento & purificación
10.
AJNR Am J Neuroradiol ; 27(6): 1252-6, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16775275

RESUMEN

BACKGROUND AND PURPOSE: Retrograde cortical venous drainage (RCVD) is the most major risk factor for aggressive behavior of intracranial dural arteriovenous fistulas (DAVF). The purpose of this study was to assess the efficacy of relative cerebral blood volume (rCBV) map for RCVD in patients with DAVF. METHODS: Ten patients with angiographically proven DAVF with RCVD, 2 reference patients with DAVF without RCVD, and 10 control subjects underwent examinations with dynamic susceptibility contrast (DSC)-MR imaging. Four patients with DAVF with unilateral RCVD were evaluated, before and after treatment. The calculation of mean rCBV ratio was performed on a hemispheric basis. The mean rCBV ratio was defined as the value on one side (higher value side) divided by that on the other side (lower value side). RESULTS: In all patients with DAVF with RCVD, the rCBV map showed an increase in rCBV of the angiographically proved affected hemisphere. In 2 reference patients with DAVF without RCVD and all control subjects, the rCBV map showed no increase of rCBV. The mean rCBV ratio in patients with DAVF with RCVD was significantly higher than that of control subjects (P = .0002). Treatment response for RCVD was indicated by a decrease of CBV on the rCBV map and by a decrease of 22% in the mean rCBV ratio. CONCLUSIONS: Increased rCBV by DSC-MR correlated with RCVD in patients with DVAF. The assessment with rCBV for RCVD may be more quantitative than that with angiogram.


Asunto(s)
Volumen Sanguíneo , Malformaciones Vasculares del Sistema Nervioso Central/diagnóstico , Circulación Cerebrovascular , Medios de Contraste , Angiografía por Resonancia Magnética , Anciano , Determinación del Volumen Sanguíneo , Malformaciones Vasculares del Sistema Nervioso Central/diagnóstico por imagen , Malformaciones Vasculares del Sistema Nervioso Central/fisiopatología , Angiografía Cerebral , Femenino , Humanos , Masculino , Persona de Mediana Edad
11.
Cancer Res ; 48(3): 609-14, 1988 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-3257169

RESUMEN

An androgen-independent, transplantable prostate carcinoma line (AIT), originally derived from the dorsolateral prostate (DLP) of Noble rat, was implanted into orchiectomized Noble rats and its response to androgen stimulation was studied and compared to that of the regenerating DLP tissue in sexually ablated rats. AIT tumors carried in castrated hosts displayed a high basal level of proliferative activity (mitotic index (MI), 15.0 +/- 0.5) while DLP tissue in untreated castrates exhibited no proliferative activity. Following androgen stimulation by testosterone capsule implantation into host rats, the AIT responded with a marked increase in cell proliferation; MI values doubled to 30.0 +/- 2.9 on Day 5 following androgen stimulation. This androgen-induced increase in MI values was coincident with elevations in nuclear androgen receptor (20-fold increase) and 5 alpha-dihydrotestosterone content (3-fold increase) in the tumor. However, by Day 10 following androgen treatment, indices of cell proliferation in the AIT declined to pre-androgen-stimulated levels (MI, 14.8 +/- 1.9) despite the continued elevations in nuclear androgen receptor and tissue 5 alpha-dihydrotestosterone contents. Parallel changes in MI were also observed in the normal regenerating DLP following androgen stimulation. MI values in this tissue increased from nondetectable levels to 38.1 +/- 4.7 on Day 5 but declined to relatively low levels (4.5 +/- 0.9) by Day 10 following androgen replacement. Taken together these findings led us to conclude that the AIT carried in castrates is capable of responding to testosterone in a manner similar to that observed for androgen-stimulated DLP of sexually ablated rats. Thus, in both the neoplastic and regenerating tissues, the initial response to androgen is characterized by a marked enhancement of cell proliferation which was correlated with an increase in androgen receptor and 5 alpha-dihydrotestosterone content. However, like its tissue of origin, the AIT possesses mechanisms which act to limit androgen-induced cell division despite continued elevations in key parameters of androgen activation.


Asunto(s)
Carcinoma/metabolismo , División Celular/efectos de los fármacos , Dihidrotestosterona/metabolismo , Neoplasias de la Próstata/metabolismo , Receptores Androgénicos/metabolismo , Testosterona/farmacología , Animales , Núcleo Celular/metabolismo , Citosol/metabolismo , Estrenos/metabolismo , Masculino , Metribolona , Índice Mitótico/efectos de los fármacos , Orquiectomía , Ratas , Testosterona/sangre
12.
Biochim Biophys Acta ; 1490(1-2): 159-62, 2000 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-10786631

RESUMEN

The first step of C-P compound biosynthesis is a C-P bond formation reaction catalyzed by phosphoenolpyruvate phosphomutase, but this reaction favors the cleavage of the C-P bond. This C-P bond forming reaction is driven by the following reaction catalyzed by phosphonopyruvate (PnPy) decarboxylase. We have cloned and sequenced the gene (bcpC) encoding PnPy decarboxylase, a key enzyme of C-P compound biosynthesis, from the bialaphos (BA) producing microorganism Streptomyces hygroscopicus by complementation methods using Streptomyces wedmorensis NP-7, which is a mutant of a fosfomycin producing strain deficient in this step. The location of this gene in the BA biosynthetic gene cluster was determined by using the expression system in Streptomyces lividans. DNA sequencing of this gene revealed a 1203-bp open reading frame encoding a polypeptide of 401 amino acids.


Asunto(s)
Proteínas Bacterianas , Carboxiliasas/genética , Genes Bacterianos , Streptomyces/genética , Carboxiliasas/biosíntesis , Carboxiliasas/química , Expresión Génica , Herbicidas/metabolismo , Datos de Secuencia Molecular , Familia de Multigenes , Compuestos Organofosforados/metabolismo , Fosfotransferasas (Fosfomutasas)/metabolismo , Plásmidos , Streptomyces/enzimología
13.
Biochim Biophys Acta ; 1294(2): 177-82, 1996 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-8645736

RESUMEN

Quinolidomicin A1, a 60-membered macrolide purified from an actinomycete Micromonospora sp. markedly induced 45Ca2+ release from the heavy fraction of skeletal muscle sarcoplasmic reticulum (HSR), but induced only slightly from the light fraction of sarcoplasmic reticulum (LSR), showing a lack of the ionophoretic activity even at a high concentration (300 microM). This was also confirmed by measuring the 45Ca2+ transport activity of quinolidomicin A1 across an organic solvent barrier. Quinolidomicin A1 (3-300 microM) increased 45Ca2+ release from HSR with an EC50 value of approx. 20 microM. The potency of quinolidomicin A1 was approx. 100-fold higher than that of caffeine. The bell-shaped profile of Ca2+ dependence for quinolidomicin A1 was different from that for caffeine. Blockers of Ca2+ release channels such as Mg2+ (10 mM), procaine (10 mM) and ruthenium red (10 microM) partially blocked quinolidomicin A1 (30 microM)-induced 45Ca2+ release from HSR. At 0 degrees C, quinolidomicin A1-induced 45Ca2+ release was ascertained not to be due to the inhibition of Ca2+ ATPase by the ATPase assay. Quinolidomicin A1 potentiated [3H]ryanodine binding to HSR with a decrease in KD but without a change in Bmax. These results suggest that quinolidomicin A1-induced Ca2+ release from HSR is consisted of two components, which are both sensitive and insensitive to blockers of Ca2+ release channels, and that the former component is associated with the ryanodine receptor.


Asunto(s)
Antibacterianos/farmacología , Calcio/metabolismo , Macrólidos , Músculo Esquelético/metabolismo , Retículo Sarcoplasmático/metabolismo , Actinomycetales , Análisis de Varianza , Animales , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antibióticos Antineoplásicos/farmacología , Transporte Biológico/efectos de los fármacos , Cafeína/farmacología , Radioisótopos de Calcio , Cinética , Estructura Molecular , Conejos , Rianodina/metabolismo , Retículo Sarcoplasmático/efectos de los fármacos
14.
Biochim Biophys Acta ; 1308(3): 256-62, 1996 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-8809118

RESUMEN

The in vitro relationship between eukaryotic DNA polymerases and fatty acids was investigated. Some fatty acids strongly inhibited the activities of DNA polymerase alpha and/or beta in vitro. The kinetics of inhibition by linoleic acid showed that DNA polymerase alpha was non-competitively inhibited with respect to the DNA template and substrate (dTTP), while DNA polymerase beta was inhibited competitively with both DNA and substrate.


Asunto(s)
Ácidos Grasos/farmacología , Inhibidores de la Síntesis del Ácido Nucleico , Animales , Bovinos , ADN Polimerasa I/antagonistas & inhibidores , ADN Polimerasa I/metabolismo , ADN Polimerasa II/antagonistas & inhibidores , ADN Polimerasa II/metabolismo , ADN Polimerasa Dirigida por ADN/metabolismo , Detergentes/farmacología , Ácidos Grasos/química , Cinética , Ácido Linoleico , Ácidos Linoleicos/farmacología , Octoxinol , Polietilenglicoles/farmacología , Ratas , Nucleótidos de Timina/metabolismo
15.
Plant Physiol ; 113(3): 773-778, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12223642

RESUMEN

Biosynthesis of GA73 methyl ester (GA73-Me), the principal antheridiogen in Lygodium ferns, was investigated. From the methanol extract of prothallia of Lygodium circinnatum, GA25, GA73, GA73-Me, GA88-Me, and a few unknown GA73 derivatives were detected by GC-MS. Because the presence of GA25 suggests that GA24, a direct precursor of GA25, could also be present in L. circinnatum prothallia, we used feeding experiments to investigate the possibility that GA24 is a precursor of GA73-Me. In L. circinnatum prothallia, [2H2]GA24 was converted into [2H2]GA73-Me and a trace amount of [2H2]GA9-Me, whereas [2H3]GA9 was converted into [2H3]GA9-Me and [2H3]monohydroxy-GA9-Me. Because GA73-Me, GA9-Me, and their monohydroxy derivatives had been identified by GC-MS from the culture medium of L. circinnatum prothallia, our results suggest that GA73-Me is biosynthesized from GA24 via GA73, and that neither GA9 nor GA9-Me is a precursor of GA73-Me. Though the possibility had been suggested that GA73-Me is biosynthesized from 9,15-cyclo-GA9 (GA103), [2H2]GA103 was not converted into [2H2]GA73-Me.

16.
Phys Rev E Stat Nonlin Soft Matter Phys ; 71(1 Pt 1): 011801, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15697622

RESUMEN

We report neutron spin-echo measurements on two types of poly(vinyl alcohol) (PVA) gels. The first is PVA gel in a mixture of dimethyl sulfoxide (DMSO) and water with volume ratio 60/40 , and the second is PVA gel in an aqueous borax solution. The observed normalized intermediate scattering functions I (Q,t) /I (Q,0) are very different between them. The former I (Q,t) /I (Q,0) shows a nondecaying component in addition to a fast decay, but the latter does not have the nondecaying one. This clearly indicates that the fluctuations in the former PVA gel consist of static and dynamic fluctuations whereas the latter PVA gel does include only the dynamic fluctuations. The dynamic fluctuations of the former and latter gels have been analyzed in terms of a restricted motion in the network and Zimm motion, respectively, and the origins of these motions will be discussed.

17.
Mol Plant Microbe Interact ; 14(2): 261-4, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11204791

RESUMEN

Jasmonic acid (JA) transiently accumulated during temperature-dependent synchronous necrotic lesion formation in Tobacco mosaic virus-infected tobacco leaves. The accumulation of JA was preceded by activation of a tobacco mitogen-activated protein kinase, WIPK, which functions upstream of JA in wound signal transduction pathways.


Asunto(s)
División Celular , Ciclopentanos/metabolismo , Nicotiana/metabolismo , Plantas Tóxicas , Virus del Mosaico del Tabaco/fisiología , Sistema de Señalización de MAP Quinasas , Oxilipinas , Hojas de la Planta/citología , Hojas de la Planta/enzimología , Hojas de la Planta/metabolismo , Hojas de la Planta/virología , Nicotiana/citología , Nicotiana/enzimología , Nicotiana/virología
18.
Gene ; 158(1): 149-50, 1995 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-7789803

RESUMEN

The nucleotide sequence of the Streptomyces hygroscopicus gene encoding P-methyltransferase, catalyzing the formation of a carbon-phosphorus bond, involved in bialaphos biosynthesis, has been determined. The amino-acid sequence deduced from the nt sequence, shows homology with those of magnesium-protoporphyrin IX monomethyl ester oxidative cyclase (Mg-ProtoMe cyclase) of Rhodobacter capsulatus and the enzyme catalyzing the methylation of the aldehyde carbon of phosphonoacetaldehyde in fosfomycin biosynthesis.


Asunto(s)
Herbicidas/metabolismo , Metiltransferasas/genética , Compuestos Organofosforados/metabolismo , Streptomyces/genética , Secuencia de Aminoácidos , Secuencia de Bases , ADN Bacteriano , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Homología de Secuencia de Aminoácido , Streptomyces/enzimología , Streptomyces/metabolismo
19.
Gene ; 153(1): 143-4, 1995 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-7883179

RESUMEN

The nucleotide (nt) sequence of the Streptomyces hygroscopicus gene encoding carboxyphosphonoenolpyruvate (CPEP) synthase, that catalyzes a transesterification between phosphoenolpyruvate (PEP) and phosphonoformate (PF) in the bialaphos biosynthetic pathway, has been determined. The amino-acid sequence deduced from the nt sequence is similar to several eukaryotic 2-phospho-D-glycerate hydrolases (EC 4.2.1.11).


Asunto(s)
Proteínas Bacterianas/genética , Genes Bacterianos , Fosfopiruvato Hidratasa/genética , Streptomyces/genética , Secuencia de Aminoácidos , Proteínas Bacterianas/metabolismo , Secuencia de Bases , Esterificación , Datos de Secuencia Molecular , Compuestos Organofosforados/metabolismo , Fosfopiruvato Hidratasa/química , Fosfopiruvato Hidratasa/metabolismo , Fosfotransferasas (Fosfomutasas)/metabolismo , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Streptomyces/enzimología
20.
Am J Psychiatry ; 158(10): 1717-9, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11579008

RESUMEN

OBJECTIVE: High-resolution magnetic resonance imaging was used to evaluate the prevalence of the cavum septi pellucidi (CSP) in 79 normal subjects and 86 patients with schizophrenia. METHOD: The CSP was assessed by counting the number of consecutive coronal 1-mm slices containing the CSP. A CSP equal to or greater than 6 mm in length was defined as large. RESULTS: The CSP was found in 74.4% of the patients and 74.7% of the normal subjects, a nonsignificant difference. No difference between groups was found in the prevalence of a large CSP. CONCLUSIONS: The findings support the idea that a small CSP is a normal anatomical variant. More cases of a large CSP are needed to elucidate the implications of this abnormality in schizophrenia.


Asunto(s)
Imagen por Resonancia Magnética/estadística & datos numéricos , Esquizofrenia/diagnóstico , Tabique Pelúcido/anatomía & histología , Adulto , Femenino , Humanos , Masculino , Prevalencia , Esquizofrenia/patología , Tabique Pelúcido/anomalías , Tabique Pelúcido/patología , Factores Sexuales
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