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1.
Biochim Biophys Acta ; 1273(1): 62-70, 1996 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-8573596

RESUMEN

Systems for overexpression and purification of active alpha, beta and gamma subunits of Escherichia coli H(+)-ATPase were established. The alpha and beta subunits recovered as soluble form were purified by hydroxyapatite column chromatography. Since the gamma subunit was overexpressed as the insoluble form, this subunit was purified by polyacrylamide gel-electrophoresis containing sodium dodecyl sulfate. By subsequent denaturation of this subunit with guanidine hydrochloride and renaturation, the active gamma subunit for reconstitution of the F1-ATPase activity with the purified alpha and beta subunit was obtained. The delta and epsilon subunits which were fused to the carboxy terminus of glutathione S-transferase (GST) were overproduced and purified by affinity chromatography. These fused proteins (delta-GST and epsilon-GST) were incubated with the purified alpha, beta and gamma subunits and applied to affinity chromatography. The alpha beta gamma delta-GST and alpha beta gamma epsilon-GST complex were eluted specifically by addition of glutathione and exhibited high and low ATPase activity, respectively, with a subunit stoichiometry similar to that in the native F1-ATPase, indicating that active complexes could be reconstituted with the fused proteins. These results suggested that the amino-terminal ends of the delta and epsilon subunits are not involved in formation of the active complex. The fused epsilon-GST bound the gamma subunit strongly, and the alpha subunit weakly. The delta-GST bound the gamma subunit significantly, and the alpha and beta subunits very weakly.


Asunto(s)
Escherichia coli/enzimología , Glutatión Transferasa/química , ATPasas de Translocación de Protón/química , Secuencia de Bases , Glutatión , Glutatión Transferasa/aislamiento & purificación , Ligandos , Datos de Secuencia Molecular , Plásmidos , ATPasas de Translocación de Protón/aislamiento & purificación , Proteínas Recombinantes de Fusión/química
2.
Diabetes Care ; 24(12): 2127-33, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11723095

RESUMEN

OBJECTIVE: The significance of abdominal visceral fat accumulation was evaluated in Japanese men with impaired glucose tolerance (IGT). RESEARCH DESIGN AND METHODS: The IGT subjects (n = 123) were aged 55 +/- 9 years with a BMI of 24 +/- 3 kg/m(2). The 148 control subjects with normal glucose tolerance (NGT) were matched for age and BMI. IGT and NGT were classified according to the 1985 World Health Organization criteria. Abdominal fat distribution was analyzed by computed tomography at umbilical level. Plasma lipid, glucose, and insulin concentrations and blood pressure (BP) were measured. RESULTS: In subjects with IGT, the average visceral fat area (VFA) was significantly greater than in subjects with NGT. Fasting insulin, the sum of insulin concentrations during an oral glucose tolerance test, insulin resistance according to a homeostasis model assessment for insulin resistance (HOMA-IR), systolic BP, and serum triglyceride were significantly higher, whereas the DeltaI(30-0)/DeltaG(30-0) was significantly lower, in subjects with IGT. Subjects with IGT and NGT were then divided into three subgroups according to the number of risk factors they possessed (dyslipidemia, hypertension, neither, or both). In both IGT and NGT subjects, BMI, VFA, subcutaneous fat area, fasting insulin, HOMA-IR, and insulin secretion of the homeostasis model assessment were significantly higher in the double-risk factor subgroup than in the no-risk factor subgroup, and VFA was a potent and independent variable in association with the presence of a double risk factor. CONCLUSIONS: Visceral fat accumulation is a major contributor for multiple risk factor clustering in Japanese men with IGT and NGT.


Asunto(s)
Tejido Adiposo , Composición Corporal , Intolerancia a la Glucosa , Vísceras , Presión Sanguínea , Ayuno , Prueba de Tolerancia a la Glucosa , Homeostasis , Humanos , Hiperlipidemias/complicaciones , Hipertensión/complicaciones , Insulina/sangre , Insulina/metabolismo , Resistencia a la Insulina , Secreción de Insulina , Modelos Logísticos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Triglicéridos/sangre
3.
J Biosci Bioeng ; 90(1): 112-4, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-16232827

RESUMEN

N-(Benzyloxycarbonyl)-L-aspartyl-L-phenylalanine methyl ester (Z-AspPheOMe), a precursor of the synthetic sweetener aspartame, was synthesized, using thermolysin immobilized onto Amberlite XAD-7, both in ethyl acetate and in tert-amyl alcohol. The initial rates for synthesis of Z-AspPheOMe in the organic solvents were predicted on the basis of a model proposed for an aqueous/organic biphasic reaction and compared with the experimentally observed substrate concentration dependencies. The experimental synthetic rates using the enzyme immobilized at a high enzyme concentration were lower than the calculated ones over a wide range of the substrate concentration. It was suggested as a reason for this discrepancy that the enzyme molecules form compact aggregates and those existing inside the aggregates cannot be utilized for reaction. The experimental results with the enzyme immobilized at a low concentration in ethyl acetate coincided well with the calculated ones. On the other hand, when tert-amyl alcohol was used, the experimental results were different in tendency irrespective of the amount of enzyme loaded, probably due to the fact that a distinct water phase does not exist around the enzyme aggregates inside the support.

4.
J Biosci Bioeng ; 90(1): 43-51, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-16232816

RESUMEN

The initial kinetics for the syntheses of N-(benzyloxycarbonyl)-L-alanyl-L-phenylalanine methyl ester (ZAPM) and N-(benzyloxycarbonyl)-L-aspartyl-L-phenylalanine methyl ester (ZDPM) in an aqueous/organic biphasic system, using free thermolysin were elucidated, both experimentally and theoretically. As model organic solvents, ethyl acetate and tert-amyl alcohol were used. The substrate concentration dependencies of the initial rate of syntheses for ZAPM and ZDPM observed in the biphasic system were well simulated using the overall partition coefficients of the substrates and product taking into consideration the effect of the formation of ion-pair complexes between the acid and amine components of the substrate, the initial rate equations determined in an aqueous buffer saturated with the organic solvent, and the pH dependence of the rate constant. The equilibrium yield for the synthesis of ZDPM was also in good agreement with the calculated result using the overall partition coefficients and equilibrium constant measured in the aqueous buffer.

5.
J Biosci Bioeng ; 87(4): 463-72, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-16232500

RESUMEN

Various factors affecting the stability of thermolysin immobilized by cross-linking with glutaraldehyde were elucidated, particularly in the water-immiscible organic solvents such as ethyl acetate and tert-amyl alcohol. The main reason for enzyme inactivation in water-immiscible organic solvents was found to be autolysis in the water phase, which may surround the enzyme immobilized inside the support. By contrast, in water-miscible organic solvents thermal denaturation was the predominant cause of enzyme inactivation. Courses of inactivation were expressed by second-order kinetics in the initial stage, after which inactivation proceeded at a slower rate. The extent of autolysis was found to strongly depend on the kind of organic solvent, the water content, and type of support and these dependencies were explained by the difference in the amount and state of water inside the support. Thermolysin was immobilized onto Amberlite XAD-7 as a compact aggregate inside the support which may increase the stability of the enzyme. Finally, it was shown that the stability of the immobilized enzyme could be correlated with the logP value for water-miscible organic solvents and with the solubility of water for water-immiscible organic solvents.

6.
J Biosci Bioeng ; 88(6): 651-8, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-16232679

RESUMEN

The overall partition coefficients of the acid and amine components of amino acid derivatives, the substrates for proteinase-catalyzed synthesis of oligopeptide precursors, in an aqueous/organic biphasic system were studied both experimentally and theoretically. In a single-component system containing either an acid or amine component, the overall partition coefficient was well expressed by a model using the acid dissociation constant and partition coefficients for the non-ionized and ionized forms of the component. The overall partition coefficient in a binary-component system containing both acid and amine components was well simulated by the model when the formation of ion-pair complexes in the organic solvent phase was taken into consideration in addition to the partitioning of the non-ionized and ionized forms of the components. The formation of ion-pair complexes in the organic solvent phase was indicated by an analysis using Fourier transform infrared ray spectroscopy (FT-IR). In addition to the partition equilibrium, the aqueous-phase pH change after partitioning could be predicted by the model.

7.
J Long Term Eff Med Implants ; 10(4): 239-50, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11194608

RESUMEN

We have applied a reconstructive operation to patients with injury of the lateral ligament in the ankle joint using an artificial ligament made of polyester (Leeds-Keio) since 1985. The operation was performed on 451 feet of 436 patients. Average follow-up period was 5 years and 8 months. Talar tilt and anterior drawer translation before and after the operation were improved from 16 degrees to 4 degrees and from 11 mm to 4 mm, respectively. In this study, which has followed the same patients over an extended period, there were no cases with a decrease in the range of motion of the joint, with further development of osteoarthritis, or with a poorer result than those observed in our earlier study, which reported a short-term follow-up of the same patients. It may therefore be concluded that this reconstructive procedure of the lateral ligament of the ankle joint, using the artificial ligament, is also excellent after long-term follow-up.


Asunto(s)
Articulación del Tobillo , Inestabilidad de la Articulación/cirugía , Prótesis e Implantes , Adolescente , Adulto , Anciano , Fenómenos Biomecánicos , Niño , Femenino , Estudios de Seguimiento , Humanos , Inestabilidad de la Articulación/diagnóstico por imagen , Inestabilidad de la Articulación/etiología , Inestabilidad de la Articulación/fisiopatología , Masculino , Persona de Mediana Edad , Poliésteres , Postura , Radiografía , Rango del Movimiento Articular , Mallas Quirúrgicas , Resultado del Tratamiento
8.
Nihon Koshu Eisei Zasshi ; 39(7): 428-36, 1992 Jul.
Artículo en Japonés | MEDLINE | ID: mdl-1504337

RESUMEN

A survey of the frequency of various kinds of foods, dietary habits, life style, and health status was performed on 2,049 men aged from 40 to 59 living in an urban area who were participants in a "human dock" medical checkup. The relationships between these factors and health status were studied in order to identify a particular life style associated with good health status. The instrument utilized in this survey was a special form of a structured questionnaire. The results are summarized below. 1. The frequency of various kinds of foods were correlated with the kind of breakfast eaten, dietary habits, physical exercise habits, daily physical activity, smoking, and occupation. The strongest correlation to frequency of various kinds of foods was found to be with the kind of breakfast eaten and dietary habits. 2. Dietary habits were also correlated to various aspects of life style: smoking, drinking, the frequency of various kinds of foods, kind of breakfast eaten, daily physical activity, sleeping hours, habits related to physical exercise, and the frequency of meals eaten away from home. Dietary habits correlated most closely with the frequency of various kinds of foods and daily physical activity. The frequency of various kinds of food and dietary habits were found to correlate with various aspects of life style, and those subjects with good overall life styles were also found to have desirable dietary life styles. The correlation of desirable dietary habits, food intake and a suitable life style with good health status was confirmed by the results of clinical blood tests used as an index of health status.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Análisis Químico de la Sangre , Conducta Alimentaria , Estilo de Vida , Humanos , Masculino , Persona de Mediana Edad
14.
Br J Ophthalmol ; 92(4): 505-8, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18245272

RESUMEN

AIM: To investigative whether clinical manifestations of anterior uveitis are associated with the viral load of varicella zoster virus (VZV) in the aqueous humor in patients with herpes zoster ophthalmicus (HZO) and zoster sine herpete (ZSH). METHODS: After informed consent was given, an aliquot of aqueous humor was collected from patients with VZV anterior uveitis (n = 8). Genomic DNA of the human herpes viruses was measured in the aqueous humor by two PCR assays: a qualitative multiplex PCR and a quantitative real-time PCR. RESULTS: All patients had unilateral acute anterior uveitis with high intraocular pressure, mutton fat keratic precipitates with some pigmentation, and trabecular meshwork pigmentation. Multiplex PCR demonstrated VZV genomic DNA in all of the samples, but not in other human herpes virus samples (human simplex virus types 1 and 2, Epstein-Barr virus, cytomegalovirus and human herpes virus types 6, 7 and 8). Real-time PCR revealed a high copy number of VZV DNA in the aqueous humor. After the initial onset of anterior uveitis, iris atrophy and distorted pupil with paralytic mydriasis developed. The intensity of iris atrophy and pupil distortion, but not ocular hypertension, correlated with the viral load of VZV in the aqueous humor. CONCLUSION: VZV viral load in the aqueous humor correlated significantly with damage to the iris (iris atrophy and pupil distortion) in patients with HZO and ZSH.


Asunto(s)
Humor Acuoso/virología , Herpes Zóster Oftálmico/virología , Herpesvirus Humano 3/aislamiento & purificación , Uveítis Anterior/virología , Zoster Sine Herpete/virología , Enfermedad Aguda , Adulto , Anciano , ADN Viral/análisis , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa/métodos , Carga Viral
15.
ASDC J Dent Child ; 65(6): 495-8, 439, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9883327

RESUMEN

The authors presented a case report of a seven-year-old male with eight submerged primary molars and a primary lateral incisor. Two major treatment modalities, tooth extraction and observation, were reported. In this case we applied the two alternative modalities and observed the patient for five years. The permanent successors were in the process of almost normal eruption after the extraction of the submerged primary teeth; no eruption and more severe submerging were observed, however, in the permanent successors of the submerged primary teeth that were not extracted. These results suggest that submerged or impacted primary teeth should be extracted immediately when they are moderately or severely submerged.


Asunto(s)
Diente Primario/fisiopatología , Diente no Erupcionado/cirugía , Anodoncia/complicaciones , Niño , Diente Canino/anomalías , Humanos , Masculino , Diente Molar/fisiopatología , Diente Molar/cirugía , Extracción Dental , Diente Primario/anomalías , Diente no Erupcionado/complicaciones
16.
Biotechnol Bioeng ; 46(6): 631-5, 1995 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-18623359

RESUMEN

N-(benzyloxycarbonyl)-L-aspartyl-L-phenylalanine methyl ester, a precursor of the synthetic sweetener, aspartame, was synthesized from N-(benzyloxycarbonyl)-L-aspartic acid and L-phenylalanine methyl ester with an immobilized thermolysin (EC 3.4.24.4) in the mixed organic solvent system of tert-amyl alcohol and ethyl acetate. A mixed solvent consisting of tert-amyl alcohol and ethyl acetate at a ratio of 33:67 (v/v) was found to be the most suitable with respect to synthetic rate and stability of the immobilized enzyme. The reaction continued to proceed quite successfully in a column reactor at 40 degrees C and at a space velocity of 3.6 h(-1) with a yield of 99%, using 40 mM Z-Asp and 200 mM PheOMe dissolved in the mixed solvent as the substrate. (c) 1995 John Wiley & Sons, Inc.

17.
Biotechnol Bioeng ; 43(11): 1108-17, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-18615523

RESUMEN

N-(Benzyloxycarbonyl)-L-aspartyl-L-phenylalanine methyl ester (Z-AspPheOMe), a precursor of the aspartame, and N-(benzyloxycarbonyl)-L-phenylalanyl-Lphenylalanine methyl ester (Z-PhePheOMe) were synthesized from the respective amino acid derivatives with an immobilized thermolysin (EC 3.4.24.4) in ethyl acetate. Various factors affecting the synthesis of these dipeptide precursors were clarified. The initial synthetic rate was the highest at the water content of 3.5% for both reactions. The substrate concentration dependencies of the initial synthetic rate of Z-AspkPheOMe and Z-PhePheOMe with the immobilized enzyme in ethyl acetate were different from those in an aqueous buffer solution saturated with ethyl acetate but similar to those in the aqueous/organic biphasic system using the free enzyme. Particularly, the initial synthetic rate of Z-AspPhOMe increased in order higher than first order with respect to the concentration of L-phenylalanine methyl ester (PheOMe), whereas it decreased sharply with the concentration of N-(benzyloxycarbonyl)-L-aspartic acid (Z-Asp). Such kinetic behavior could be explained by regarding the inside of the immobilized enzyme as being a biphasic mode composed from the organic phase and aqueous phase where the enzymatic reaction takes place. The reaction in the aqueous/organic biphasic system using the free enzyme could be simulated by taking into consideration the partition of the substrate and the initial rate of synthesis in the aqueous buffer saturated with ethyl acetate. Based on this analysis, the rate of reaction with the immobilized enzyme in ethyl acetate could also be predicted. Z-AsPheOMe and Z-PhePheOMe were synthesized by the fed-batch method where the acid component of the substrate was intermittently added during the course of reaction and by the batch method. In the synthesis of Z-AspPheOMe, the synthetic rate and maximum yield of reaction as well as the stability of the immobilized enzyme were higher in the fed-batch reaction than those in the batch reaction. In the synthesis of Z-PhePheOMe, the results obtained by both methods were similar. (c) 1994 John Wiley & Sons, Inc.

18.
Biotechnol Bioeng ; 43(11): 1118-23, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-18615524

RESUMEN

N-(Benzyloxycarbonyl)-L-aspartyl-L-phenylalanine methyl ester (Z-AspPheOMe), a precursor of the synthetic sweetner asparatame, was synthesized from N-(benzyloxycarbolyl)-L-aspartic acid (Z-Asp) and L-phenylalanine methyl ester (PheOMe) with an immobilized thermolysin in various organic solvents. We found that in tert-amyl alcohol containing a small amount of water the immobilized enzyme showed a high activity comparble to that in ethyl acetate with quite a high stability. The immobilized enzyme was fully stable up to 70 degrees C in tert-amyl alcohol in the absence of the subatrate, and up to 50 degrees C in the presence of the substrate. The high stability in the presence of the substrate was found due to the fact that the release of calcium ions, the stabilizing factor of thermolysin, is suppressed.The substrate concentration dependence of the initial synthetic rate with the immobilized enzyme was quite different from that with the free enzyme in the biphasic system, in contrast to that in ethyl acetate. Finally, Z-AspPheOMe was continuously synthesized in a column reactor using 200 mM PheOMe and 120 mM Z-Asp as the substrate for over 300 h at 45 degrees C and a space velocity of 1 h(-1) without any loss of acivity. (c) 1994 John Wiley & Sons, Inc.

19.
Eur Respir J ; 10(3): 735-6, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9073015

RESUMEN

We report a case of spontaneous haemothorax in a 19 year old boy with an exostosis of the left second rib. It may have been caused by nontraumatic rupture of markedly dilated pleural vessels, as a result of long-standing friction between the exostosis and the pleura. This is the first report of spontaneous haemothorax, without penetrative injury to the pleura or the diaphragm, in a patient with hereditary multiple exostosis.


Asunto(s)
Exostosis Múltiple Hereditaria/complicaciones , Hemotórax/etiología , Costillas , Adulto , Hemotórax/diagnóstico por imagen , Hemotórax/cirugía , Humanos , Masculino , Pleura/irrigación sanguínea , Radiografía , Costillas/diagnóstico por imagen , Costillas/patología , Costillas/cirugía , Rotura Espontánea
20.
Acta Pathol Jpn ; 32(4): 677-82, 1982 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6287799

RESUMEN

An autopsy case of bronchiolo-alveolar adenocarcinoma in the lung is reported. The patient is a 70-year-old male who complained of severe cough with 500-600 ml watery sputum a day, loss of weight. and general fatigue. Autopsy revealed numerous whitish tumors in various sizes with multiple cysts in both lungs, with no metastasis being found in any other organs. Histological findings identified the tumor as a bronchiolo-alveolar adenocarcinoma originating from the lungs. Electron-microscopic findings showed that the tumor cells were covered by prominent microvilli, and contained abundant irregularly-shaped cytoplasmic vacuoles suggestive of mucin.


Asunto(s)
Adenocarcinoma Bronquioloalveolar/patología , Quistes/patología , Enfermedades Pulmonares/patología , Neoplasias Pulmonares/patología , Adenocarcinoma Bronquioloalveolar/complicaciones , Adenocarcinoma Bronquioloalveolar/ultraestructura , Anciano , Quistes/complicaciones , Humanos , Pulmón/ultraestructura , Enfermedades Pulmonares/complicaciones , Neoplasias Pulmonares/complicaciones , Neoplasias Pulmonares/ultraestructura , Masculino
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