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1.
Nature ; 530(7591): 453-6, 2016 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-26911781

RESUMEN

In recent years, millisecond-duration radio signals originating in distant galaxies appear to have been discovered in the so-called fast radio bursts. These signals are dispersed according to a precise physical law and this dispersion is a key observable quantity, which, in tandem with a redshift measurement, can be used for fundamental physical investigations. Every fast radio burst has a dispersion measurement, but none before now have had a redshift measurement, because of the difficulty in pinpointing their celestial coordinates. Here we report the discovery of a fast radio burst and the identification of a fading radio transient lasting ~6 days after the event, which we use to identify the host galaxy; we measure the galaxy's redshift to be z = 0.492 ± 0.008. The dispersion measure and redshift, in combination, provide a direct measurement of the cosmic density of ionized baryons in the intergalactic medium of ΩIGM = 4.9 ± 1.3 per cent, in agreement with the expectation from the Wilkinson Microwave Anisotropy Probe, and including all of the so-called 'missing baryons'. The ~6-day radio transient is largely consistent with the radio afterglow of a short γ-ray burst, and its existence and timescale do not support progenitor models such as giant pulses from pulsars, and supernovae. This contrasts with the interpretation of another recently discovered fast radio burst, suggesting that there are at least two classes of bursts.

2.
Ann Oncol ; 23(12): 3051-3057, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22767585

RESUMEN

BACKGROUND: The aim of this study was to investigate the clinicopathological characteristics of GATA binding protein 3 (GATA3)-positive breast cancers as well as the association of GATA3 expression with response to chemotherapy. PATIENTS AND METHODS: Tumor specimens obtained before neoadjuvant chemotherapy [paclitaxel followed by 5-fluorouracil/epirubicin/cyclophosphamide)] from breast cancer patients (n = 130) were subjected to immunohistochemical and mutational analysis of GATA3 and DNA microarray gene expression analysis for intrinsic subtyping. RESULTS: Seventy-four tumors (57%) were immunohistochemically positive for GATA3. GATA3-positive tumors were significantly more likely to be lobular cancer, estrogen receptor (ER)-positive, progesterone receptor (PgR)-positive, Ki67-negative, and luminal A tumors. Somatic mutations were found in only three tumors. Pathological complete response (pCR) was observed in 8 (11%) GATA3-positive tumors and in 22 (39%) GATA3-negative tumors. multivariate analysis showed that tumor size, human epidermal growth factor receptor 2 (her2), and gata3 were independent predictors of pcr. CONCLUSIONS: GATA3-positive breast cancers showed luminal differentiation characterized by high ER expression and were mostly classified as luminal-type tumors following intrinsic subtyping. Interestingly, GATA3 was an independent predictor of response to chemotherapy, suggesting that GATA3 might be clinically useful as a predictor of a poor response to chemotherapy.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama , Factor de Transcripción GATA3/metabolismo , Paclitaxel/uso terapéutico , Adulto , Anciano , Secuencia de Bases , Neoplasias de la Mama/clasificación , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Ciclofosfamida/uso terapéutico , Epirrubicina/uso terapéutico , Receptores ErbB/metabolismo , Femenino , Fluorouracilo/uso terapéutico , Factor Nuclear 3-alfa del Hepatocito/metabolismo , Humanos , Antígeno Ki-67/metabolismo , Persona de Mediana Edad , Mucina-1/metabolismo , Terapia Neoadyuvante , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Análisis de Secuencia de ADN , Resultado del Tratamiento
3.
Int J Clin Pharmacol Ther ; 48(11): 708-17, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20979929

RESUMEN

OBJECTIVE: To investigate potential differences in zibotentan pharmacokinetics between Japanese and Caucasian patients with hormone-resistant prostate cancer (HRPC) following single and multiple dosing. METHODS: In the Japanese study, 18 patients received a single dose of zibotentan 5, 10 or 15 mg followed by 72 h washout before 26 days' once-daily dosing. In the Caucasian study, 21 patients received a single dose of zibotentan 5, 10 or 15 mg followed by 72 h washout before 12 days' once-daily dosing. RESULTS: Pharmacokinetic parameters were similar between populations. Absorption of zibotentan was rapid with maximum plasma concentrations typically achieved within 3 h of dosing. Mean clearance, 17.9 and 18.7 ml/min in Japanese and Caucasian patients, respectively (range 7.0 - 36.3 ml/min in Japanese patients and 7.8 - 29.5 ml/min in Caucasian patients) and volume of distribution, 14.0 and 15.6 l for Japanese and Caucasian patients, respectively (range 7.9 - 29.1 l in Japanese patients and 9.6 - 23.8 l in Caucasian patients) were relatively low, and t1/2 was approximately 12 h (range 5.7 - 18.8 h in Japanese patients and 5.0 - 22.9 h in Caucasian patients) following single dosing. Little accumulation was observed following daily dosing and multiple-dose pharmacokinetics were predictable. Exposure levels achieved in some Japanese patients receiving zibotentan 15 mg were higher than those observed in Caucasian patients, however, this may be due to differences in body weight, as exposure levels were similar when data were normalized for body weight. Zibotentan was well tolerated in both populations. CONCLUSIONS: There are no clinically relevant differences in the disposition and pharmacokinetics of zibotentan between Japanese and Caucasian patients with HRPC.


Asunto(s)
Antineoplásicos/farmacocinética , Neoplasias de la Próstata/tratamiento farmacológico , Pirrolidinas/farmacocinética , Anciano , Anciano de 80 o más Años , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Pueblo Asiatico , Peso Corporal , Relación Dosis-Respuesta a Droga , Antagonistas de los Receptores de la Endotelina A , Semivida , Humanos , Japón , Masculino , Persona de Mediana Edad , Neoplasias de la Próstata/patología , Pirrolidinas/administración & dosificación , Pirrolidinas/efectos adversos , Distribución Tisular , Población Blanca
4.
Protein Sci ; 3(8): 1245-52, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7987219

RESUMEN

Reversible unfolding of rat testis fructose 6-phosphate,2-kinase:fructose 2,6-bisphosphatase in guanidine hydrochloride was monitored by following enzyme activities as well as by fluorescence methodologies (intensity, emission maximum, polarization, and quenching), using both intrinsic (tryptophan) and extrinsic (5((2-(iodoacetyl)amino) ethyl)naphthalene-1-sulfonic acid) probes. The unfolding reaction is described minimally as a 4-state transition from folded dimer-->partially unfolded dimer-->monomer-->unfolded monomer. The partially unfolded dimer had a high phosphatase/kinase ratio due to preferential unfolding of the kinase domain. The renaturation reaction proceeded by very rapid conversion (less than 1 s) of unfolded monomer to dimer, devoid of any enzyme activity, followed by slow (over 60 min) formation of the active enzyme. The recovery rates of the kinase and the phosphatase were similar. Thus, the refolding appeared to be a reversal of the unfolding pathway involving different forms of the transient dimeric intermediates. Fluorescence quenching studies using iodide and acrylamide showed that the tryptophans, including Trp-15 in the N-terminal peptide, were only slightly accessible to iodide but were much more accessible to acrylamide. Fructose 6-phosphate, but not ATP or fructose 2,6-bisphosphate, diminished the iodide quenching, but all these ligands inhibited the acrylamide quenching by 25%. These results suggested that the N-terminal peptide (containing a tryptophan) was not exposed on the protein surface and may play an important role in shielding other tryptophans from solvent.


Asunto(s)
Complejos Multienzimáticos/química , Monoéster Fosfórico Hidrolasas/química , Fosfotransferasas/química , Acrilamidas/farmacología , Animales , Polarización de Fluorescencia , Fructosafosfatos/farmacología , Guanidina , Guanidinas/farmacología , Yoduros/farmacología , Sustancias Macromoleculares , Masculino , Fosfofructoquinasa-2 , Desnaturalización Proteica , Pliegue de Proteína , Ratas , Proteínas Recombinantes/química , Espectrometría de Fluorescencia , Testículo/enzimología
5.
Endocrinology ; 131(1): 441-6, 1992 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1319324

RESUMEN

When isolated rat fat pads were incubated with vanadate, the low Michaelis-Menten constant (Km) cAMP phosphodiesterase (PDE) activity in the microsomal fraction was increased in a time- and dose-dependent manner with vanadate. 3',5'-Cyclic GMP inhibited the vanadate-stimulated PDE activity with similar profile to the insulin-stimulated one. The stimulatory effect of vanadate was inhibited by inhibitors of tyrosine kinases such as amiloride, biochanin A, and genistein to various extents. Vanadate and insulin both showed the full effect in the absence of either K+, N+, or Ca2+ in the medium, while preincubation of the fat pads with a chelator of intracellular Ca2+ inhibited the vanadate action in a dose-dependent manner. The insulin action was not inhibited by it at tested concentrations. These results suggest that the vanadate action, in contrast to the insulin one, is dependent on the intracellular level of Ca2+. Preincubation of the fat pads with inhibitors of protein kinase C such as 1-(5-isoquinoline sulfonyl)-2-methylpiperazine (H-7) and staurosporine inhibited, in part, the vanadate action but did not inhibit the insulin one. Furthermore, vanadate increased the protein kinase C activity in fat pads but insulin did not increase. H-7 and amiloride showed a significant inhibition of stimulation of protein kinase C activity by vanadate. These results suggest that vanadate stimulates, in part, the 3',5'-cyclic GMP-inhibited low Km cAMP PDE activity in the microsomal fraction of fat pads through the activation of tyrosine kinase and protein kinase C-mediated processes.


Asunto(s)
3',5'-AMP Cíclico Fosfodiesterasas/metabolismo , Tejido Adiposo/enzimología , GMP Cíclico/farmacología , Vanadatos/farmacología , 1-(5-Isoquinolinesulfonil)-2-Metilpiperazina , Alcaloides/farmacología , Amilorida/farmacología , Animales , Relación Dosis-Respuesta a Droga , Activación Enzimática/efectos de los fármacos , Insulina/farmacología , Isoquinolinas/farmacología , Cinética , Masculino , Microsomas/enzimología , Piperazinas/farmacología , Proteína Quinasa C/antagonistas & inhibidores , Proteína Quinasa C/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Ratas , Ratas Endogámicas , Receptor de Insulina/efectos de los fármacos , Receptor de Insulina/fisiología , Estaurosporina , Vanadatos/administración & dosificación
6.
Bone Marrow Transplant ; 13(2): 181-5, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7515741

RESUMEN

Peripheral blood lymphocytes (PBL) from 24 allogeneic bone marrow transplant (BMT) recipients were studied serially using flow cytometry and two-color analysis. Dual labelling with two monoclonal antibodies (moAbs), CD8/S6F1 (CD11a) and CD8/CD57 was used to analyze the surface phenotypes of PBL after allogeneic BMT. In patients with acute and chronic GVHD, CD8+S6F1+ cells were markedly increased from the onset of GVHD and recovered to normal range 6 years after transplantation. By contrast, CD8+S6F1- cells fell below normal range and remained markedly decreased for 2-3 years after transplantation in patients with acute and chronic GVHD. A slight but significant increase of CD8+CD57- cells was observed with clinical signs of acute GVHD. On the other hand, CD8+CD57+ cells were increased after the onset of acute and chronic GVHD and recovered to normal range 6 years after transplantation. These results suggest that these subsets of CD8+ cells may play important roles in the pathophysiology of GVHD.


Asunto(s)
Anticuerpos Monoclonales/análisis , Antígenos CD/análisis , Antígenos de Diferenciación de Linfocitos T/análisis , Trasplante de Médula Ósea/efectos adversos , Antígenos CD8/análisis , Enfermedad Injerto contra Huésped/inmunología , Enfermedad Injerto contra Huésped/patología , Linfocitos/inmunología , Linfocitos/patología , Adolescente , Adulto , Anticuerpos Monoclonales/inmunología , Antígenos CD/inmunología , Antígenos de Diferenciación de Linfocitos T/inmunología , Trasplante de Médula Ósea/inmunología , Antígenos CD11 , Antígenos CD57 , Antígenos CD8/inmunología , Femenino , Citometría de Flujo , Enfermedad Injerto contra Huésped/fisiopatología , Humanos , Subgrupos Linfocitarios/inmunología , Subgrupos Linfocitarios/patología , Subgrupos Linfocitarios/fisiología , Linfocitos/fisiología , Masculino , Persona de Mediana Edad , Fenotipo , Factores de Tiempo
7.
J Biochem ; 78(6): 1287-96, 1975 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-5423

RESUMEN

A proteinase from the sarcocarp of melon (Cucumis Melo L. var. Prince) was purified by a three-step procedure involving batch-wise treatment with CM-cellulose fibers, column chromatography on CM-cellulose powder and gel filtration on Sephadex G-75. The final enzyme preparation was homogeneous on acrylamide gel electrophoresis. Its molecular weight was estimated by two different methods to be about 50,000. Anlayses indicated tha presence of 475 amino acid residues and at least 7 moles of hexose. The maximum activity was found in the alkaline pH region against casein as a substrate. The optimum temperature against casein was 70 degrees at pH 7.1. The enzyme was strongly inhibited by diisopropyl fluorophosphate, partly inhibited by HgCl2 and not inhibited by EDTA, p-chloromercuribenzoic acid, N-tosyl-L-lysine chloromethyl ketone, N-tosyl-L-phenylalanine chloromethyl ketone, and soybean trypsin inhibitor. The reduced and carboxymethylated insulin B-chain was cleaved at the peptide bonds of Asn3-Gln4, Cm-Cys7-Gly8, Glu13-Ala14, Leu15-Tyr16, Cm-Cys19-Gly20, Phe25-Tyr26, Pro28-Lys29, and Lys29-Ala30 by the enzyme.


Asunto(s)
Péptido Hidrolasas , Plantas/enzimología , Aminoácidos/análisis , Cationes Bivalentes , Diurona/farmacología , Ácido Edético/farmacología , Concentración de Iones de Hidrógeno , Cinética , Mercurio/farmacología , Peso Molecular , Fragmentos de Péptidos/análisis , Péptido Hidrolasas/aislamiento & purificación , Péptido Hidrolasas/metabolismo , Reactivos de Sulfhidrilo/farmacología , Temperatura
8.
J Biochem ; 81(2): 477-83, 1977 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14950

RESUMEN

An inorganic pyrophosphatase [EC 3.6.1.1] was isolated from Thiobacillus thiooxidans and purified 975-fold to a state of apparent homogeneity. The enzyme catalyzed the hydrolysis of inorganic pyrophosphate and no activity was found with a variety of other phosphate esters. The cation Mg2+ was required for maximum activity; Co2+ and Mn2+ supported 25 per cent and 10.6 per cent of the activity with Mg2+, respectively. The pH optimum was 8.8. The molecular weight was estimated to be 88,000 by gel filtration and SDS gel electrophoresis, and the enzyme consisted of four identical subunits. The isoelectric point was found to be 5.05. The enzyme was exceptionally heat-stable in the presence of 0.01 M Mg2+.


Asunto(s)
Acidithiobacillus thiooxidans/enzimología , Pirofosfatasas/metabolismo , Thiobacillus/enzimología , Azidas/farmacología , Cationes Bivalentes/farmacología , Cianuros/farmacología , Fluoruros/farmacología , Calor , Concentración de Iones de Hidrógeno , Magnesio/farmacología , Peso Molecular , Pirofosfatasas/aislamiento & purificación
9.
J Biochem ; 109(1): 99-105, 1991 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2016279

RESUMEN

As we previously reported [Sakakibara et al. (1986) Biochem. Biophys. Res. Commun. 137, 443-452; and Tominaga et al. (1989) J. Biochem. 105, 992-997], subunits of human chorionic gonadotropin (hCG) containing immature N-linked sugar chains (immature subunits), i.e., the 21 kDa form of alpha-subunit and the 23 and 19 kDa forms of beta-subunit, are present predominantly in first trimester placental cells. The molecular mass of intracellular hCG consisting of these subunits, based on gel filtration, was approximately 200 kDa, suggesting homo- or hetero-oligomerization of intracellular hCG. In the present study, we purified the 21 kDa form of alpha-subunit as well as the 23 and 19 kDa forms of beta-subunit from fresh normal first trimester placental tissues by gel filtration and reverse-phase high-performance liquid chromatography. Purified subunits were hydrolyzed (with a decrease in their molecular weighs) by endoglycosidase H and alpha-mannosidase but not by sialidase or sialidase followed by O-glycanase, indicating that those forms have presumably only high-mannose-type N-linked sugar chains but not O-linked sugar chains of the type present in mature beta-subunit. Fifteen cycles of Edman degradation of the purified forms of the subunits were performed. Only one phenylthiohydantoin amino acid, which was the same amino acid as in the urinary beta-subunit, was detected at each step for the mixture of 23 and 19 kDa forms of beta-subunit, indicating that the protein backbones of both forms are identical to each other as well as to the urinary beta-subunit.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Gonadotropina Coriónica/aislamiento & purificación , Placenta/química , Secuencia de Aminoácidos , Secuencia de Carbohidratos , Gonadotropina Coriónica/química , Cromatografía en Gel , Femenino , Glicósido Hidrolasas , Humanos , Datos de Secuencia Molecular , Peso Molecular , Embarazo , Conformación Proteica
10.
J Biochem ; 99(2): 569-77, 1986 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3516984

RESUMEN

Seven proteinases were isolated from the fruit of snake-gourd, Trichosanthes cucumeroides Maxim. Their isozymes are all serine proteinases, and homologous in their respective molecular weights, amino acid compositions, and enzymatic properties. Their molecular weight was estimated to be about 50,000. Using casein as a substrate, the maximum activity was found in the alkaline pH region. The optimum temperature using casein was 70 degrees C at pH 7.3. The enzymes were strongly inhibited by diisopropyl fluorophosphate and not inhibited by inhibitors of sulfhydryl or metalloproteases. The reduced and S-carboxymethylated insulin B-chain was used as a substrate in an investigation of the specificity. The enzyme was found to have a wide specificity for this substrate but preferentially hydrolyzed the peptide bonds involving the carboxyl groups of charged amino acid such as S-cm-cysteine, glutamic acid, histidine, arginine, and lysine. Experimental evidence indicated that the snake-gourd proteinases are similar in their properties to cucumisin, which is isolated from the sarcocarp of melon fruit.


Asunto(s)
Endopeptidasas/aislamiento & purificación , Plantas/enzimología , Serina Endopeptidasas , Aminoácidos/análisis , Sitios de Unión , Endopeptidasas/metabolismo , Concentración de Iones de Hidrógeno , Insulina , Cinética , Peso Molecular , Temperatura
11.
J Biochem ; 95(3): 825-9, 1984 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-6427203

RESUMEN

Cucumisin is a diisopropyl fluorophosphate-sensitive enzyme. The inactivation by DFP is accompanied by the formation of 1 mol of labeled serine residue per mol of enzyme. From the soluble portion of the chymotryptic digest of the diisopropyl phosphoryl derivative of cucumisin, two peptides containing phosphorus were isolated; their amino acid sequences were determined to be Gly-Thr-Ser(P)-Met and Asn-Ile-Ile-Ser-Gly-Thr-Ser(P)-Met, respectively. The four residues Gly-Thr-Ser-Met in the above amino acid sequence are identical with those of subtilisin.


Asunto(s)
Endopeptidasas/aislamiento & purificación , Plantas/enzimología , Serina Endopeptidasas , Serina/aislamiento & purificación , Secuencia de Aminoácidos , Fenómenos Químicos , Química , Cromatografía en Gel , Fragmentos de Péptidos/aislamiento & purificación
12.
J Biochem ; 105(6): 992-7, 1989 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2768225

RESUMEN

The molecular sizes of human chorionic gonadotropin (hCG) subunits in the native state in normal first trimester placental extracts were determined by gel filtration on Sephacryl S-300, followed by SDS-polyacrylamide gel electrophoresis, protein blotting, and immunobinding analysis using anti-alpha and - beta antibodies. Mature forms of hCG subunits in the extracts were only found in the same fraction as that which contained standard urinary hCG, indicating an alpha beta dimer. On the other hand, immature forms were detected with a wide range of molecular weights, which were higher than that of standard hCG, suggesting oligomerization of associated or non-associated immature subunits. In order to determine the associated state of these subunits, various forms of associated subunits (hCG alpha beta) in placental extracts were immunoprecipitated with anti-hCG antiserum, which only recognized hCG alpha beta, and Protein A-Sepharose. They were then analyzed by SDS-polyacrylamide gel electrophoresis under reducing and non-reducing conditions, followed by immunobinding assaying. It has been suggested that there are three kinds of hCG alpha beta S (one mature and two immature). To confirm the above results and to clarify the existence of free subunits, placental extracts were subjected to two-dimensional SDS-polyacrylamide gel electrophoresis. With this technique, high molecular weight forms of immature hCG subunits were found to be present in placental cells as an oligomer of not only the alpha beta dimer but of each subunit as well.


Asunto(s)
Gonadotropina Coriónica/análisis , Placenta/análisis , Extractos de Tejidos/análisis , Gonadotropina Coriónica/orina , Cromatografía en Gel , Electroforesis en Gel Bidimensional , Femenino , Humanos , Neuraminidasa , Pruebas de Precipitina , Embarazo
13.
J Biochem ; 90(4): 1087-91, 1981 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6171565

RESUMEN

Gramicidin S (GS) containing 14C-labeled proline was synthesized by a solid-phase method, and the labeled GS dihydrochloride was obtained as crystals. The labeled GS exhibited same antibacterial activity as natural GS. Strains sensitive to GS (B. subtilis and S. aureus) and an insensitive strain (E. coli) were treated with the labeled GS, and the amount of the labeled GS adsorbed on the cells was measured. GS was adsorbed rapidly on the cells of the sensitive strains; the amount adsorbed increased linearly with GS concentration up to 1-1.5 microgram/ml, and at a lower rate at above 1.5 microgram/ml. GS molecules covered most of the cell surface at the minimum inhibitory concentration of 1.5 microgram/ml; the number of molecules adsorbed per cell was 1.3-1.4 x 10(6). No GS was adsorbed by the insensitive strain.


Asunto(s)
Bacillus subtilis/metabolismo , Escherichia coli/metabolismo , Gramicidina/metabolismo , Staphylococcus aureus/metabolismo , Adsorción , Relación Dosis-Respuesta a Droga , Gramicidina/síntesis química , Factores de Tiempo
14.
J Biochem ; 102(5): 993-1001, 1987 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2449427

RESUMEN

To determine the subcellular sites for synthesis and processing of human chorionic gonadotropin subunits in cells, first trimester placental cells were fractionated subcellularly on sucrose density gradients. Analysis of the subcellular fractions by immunobinding techniques revealed that the rough endoplasmic reticulum-rich fraction contained only intermediates having high-mannose oligosaccharides, but the Golgi-rich fraction contained not only intermediates but also mature forms which were resistant to endoglycosidase H but sensitive to neuraminidase. These results show that human chorionic gonadotropin subunits are synthesized in the rough endoplasmic reticulum as forms containing high-mannose oligosaccharides, and their maturation occurs in the Golgi apparatus by trimming with endogenous glycosidases. They are then modified by addition of complex oligosaccharides and terminal sialic acid through glycosyltransferases.


Asunto(s)
Gonadotropina Coriónica/metabolismo , Placenta/ultraestructura , Acetilglucosaminidasa/metabolismo , Fraccionamiento Celular , Centrifugación por Gradiente de Densidad , Gonadotropina Coriónica Humana de Subunidad beta , Retículo Endoplásmico/metabolismo , Femenino , Hormonas Glicoproteicas de Subunidad alfa , Aparato de Golgi/metabolismo , Humanos , Manosil-Glicoproteína Endo-beta-N-Acetilglucosaminidasa , NADPH-Ferrihemoproteína Reductasa/metabolismo , Neuraminidasa/metabolismo , Fragmentos de Péptidos/metabolismo , Hormonas Adenohipofisarias/metabolismo , Placenta/metabolismo , Embarazo
15.
J Biochem ; 121(4): 724-30, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9163524

RESUMEN

Fructose-6-phosphate,2-kinase/fructose-2,6-bisphosphatase (Fru-6-P,2-kinase/Fru-2,6-BPase), a bifunctional enzyme, catalyzes the synthesis and degradation of a potent activator, fructose-2,6-bisphosphate (Fru-2,6-P2), of phosphofructokinase, and has been postulated to be an important enzyme in the regulation of glycolysis in mammalian tissues. The purpose of this study was to determine whether or not N-bromoacetylethanolamine phosphate (BrAcNHEtOP), a specific active site-directed inactivator of Fru-6-P,2-kinase, is useful for studies on the role of Fru-6-P,2-kinase in the regulation of glycolysis in vivo. BrAcNHEtOP inactivated purified recombinant rat testis-type Fru-6-P,2-kinase as well as Fru-6-P,2-kinase in a rat liver extract, with half maximum inactivation concentrations of 2 and 15 mM, respectively, on 30 min incubation at 30 degrees C. The increases in Fru-6-P,2-kinase activity and the Fru-2,6-P2 concentration in livers, prepared from fasted rats, induced by high glucose (50 mM) perfusion were suppressed in parallel after pre-perfusion with 1 to 10 mM BrAcNHEtOP, dose-dependently. Five hours after intraperitoneal injection of BrAcNHEtOP (50 to 150 mg/kg) into mice, the Fru-6-P,2-kinase activity and Fru-2,6-P2 concentration in livers had decreased in parallel, dose-dependently. These effects continued for 24 h and were accompanied by decreases in the fructose-1,6-bisphosphate, triose phosphates, and lactate contents, although the contents of glucose-6-phosphate and fructose-6-phosphate did not change. These results suggested that BrAcNHEtOP inactivates Fru-6-P, 2-kinase, resulting in a decrease in the Fru-2,6-P2 level, which causes inactivation of phosphofructokinase and consequently inhibition of glycolysis in liver. Furthermore, the suppressed levels of Fru-6-P,2-kinase activity and metabolites in mice livers were sustained by daily injection of BrAcNHEtOP for 4 days, and body weight gain was also suppressed during the administration of BrAcNHEtOP. These results suggested that BrAcNHEtOP will be a useful reagent for studying the role of Fru-6-P,2-kinase in vivo.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Etanolaminas/farmacología , Hígado/metabolismo , Fosfotransferasas (Aceptor de Grupo Alcohol)/antagonistas & inhibidores , Animales , Glucemia/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/administración & dosificación , Ácido Láctico/sangre , Hígado/efectos de los fármacos , Hígado/enzimología , Masculino , Ratones , Ratones Endogámicos , Perfusión , Fosfofructoquinasa-2 , Fosfotransferasas (Aceptor de Grupo Alcohol)/genética , Fosfotransferasas (Aceptor de Grupo Alcohol)/metabolismo , Ratas , Ratas Wistar , Proteínas Recombinantes/efectos de los fármacos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Testículo/enzimología , Triglicéridos/sangre
16.
J Biochem ; 122(1): 122-8, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9276680

RESUMEN

A full-length cDNA, which encodes a human placental fructose-6-phosphate,2-kinase/ fructose-2,6-bisphosphatase, was constructed and expressed in Escherichia coli. The expressed protein, purified to homogeneity, showed a molecular weight of 58,000 by gel electrophoresis under denaturing conditions, compared to the deduced molecular weight of 59,410. The N-terminal sequence of 15 amino acids coincided with that of the deduced sequence. The active enzyme was a dimer as judged by molecular sieve filtration. The expressed enzyme was bifunctional with Vmax values of 142 and 0.2 milliunits/mg for the kinase and phosphatase activities, respectively. The phosphatase activity was extremely low, because one phosphatase active site residue was mutated, and consequently the kinase/phosphatase ratio was the highest among the known isozymes. Furthermore, the enzyme was phosphorylated by cAMP-dependent protein kinase, protein kinase C and also by [2-32P]fructose-2,6-bisphosphate. Phosphorylation by cAMP-dependent protein kinase and protein kinase C increased the maximal Fru-6-P,2-kinase activities by 1.8- and 1.1-fold, respectively. These results suggested that placental fructose-6-phosphate,2-kinase/ fructose-2,6-bisphosphatase is important in maintaining and regulating a relatively high rate of glycolysis in placenta.


Asunto(s)
Monoéster Fosfórico Hidrolasas/aislamiento & purificación , Monoéster Fosfórico Hidrolasas/metabolismo , Fosfotransferasas (Aceptor de Grupo Alcohol)/aislamiento & purificación , Fosfotransferasas (Aceptor de Grupo Alcohol)/metabolismo , Placenta/enzimología , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Femenino , Humanos , Isoenzimas , Cinética , Fosfofructoquinasa-2 , Monoéster Fosfórico Hidrolasas/genética , Fosforilación , Fosfotransferasas (Aceptor de Grupo Alcohol)/genética , Placenta/química , Embarazo , Proteína Quinasa C/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
17.
J Endod ; 18(2): 58-62, 1992 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19186419

RESUMEN

Although intraradicular bacteria are widely considered to be the primary etiological agents of periapical lesions, the immunobiological properties of the species in question are not adequately known. The aim of this study, therefore, was to investigate the pathobiological properties of the 10 most frequently isolated endodontopathic bacterial species. Using cellular components of the pathogens obtained by sonic extraction, we have investigated their ability to induce monocyte migration, interleukin 1 production, mitogenic responses of lymphocytes, and the polyclonal activation of B lymphocytes. It was found that all of the tested species enhanced the migration of monocytes and induced mitogenesis in B lymphocytes. The polyclonal activation of B cells and the induction of interleukin 1 by monocytes were found to be stronger in Gram-negative anaerobes. Furthermore, all of the tested species excluding Bacteroides oralis were poor T cell mitogens. These findings show that a wide range of pathobiological properties are attributable to the most frequently isolated endodontic pathogens. It thus seems plausible that a battery of complex immunological responses induced by such microbes lead to the formation of persistent periapical lesions.


Asunto(s)
Bacterias/inmunología , Cavidad Pulpar/microbiología , Periodontitis Periapical/microbiología , Tratamiento del Conducto Radicular , Actinomycetales/inmunología , Animales , Linfocitos B/inmunología , Bacteroides/inmunología , Movimiento Celular/inmunología , Células Cultivadas , Clostridium/inmunología , Humanos , Interleucina-1/inmunología , Lactobacillus plantarum/inmunología , Activación de Linfocitos/inmunología , Linfocitos/inmunología , Macrófagos Peritoneales/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C3H , Ratones Endogámicos , Ratones Desnudos , Monocitos/inmunología , Peptostreptococcus/inmunología , Periodontitis Periapical/inmunología , Staphylococcus epidermidis/inmunología , Streptococcus constellatus/inmunología , Veillonella/inmunología
18.
J Trace Elem Med Biol ; 10(3): 133-8, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8905555

RESUMEN

Dietary intakes of calcium (Ca) and iron (Fe) were investigated in 227 women (mostly housewives) in 12 regions in Japan in 1991-1993 by the 24-hour food duplicate method. Nine regions out of 12 had been previously studied in 1977-1982. Utilizing Standard Food Composition database, mean Ca and Fe-intakes in 1991-1993 were estimated to be 602 and 10.4 mg/day, respectively; the former was barely sufficient and the latter was below sufficiency when compared with the Recommended Daily Allowance in Japan for pre-menopausal women. Ca- and Fe-intake did not increase in the 10-year period. Further analysis after classification of the women into three groups of farmers in Okinawa, farmers in Mainland Japan and urban residents showed that Ca and Fe insufficiency was most evident among Okinawa farmers. The leading Ca sources were milk, pulse, vegetables and fish-shellfish, but consumption of milk was generally low, especially among Okinawa farmers. Pulse, vegetables and fish-shellfish were 3 major Fe sources; Okinawa farmers depended more on vegetables and less on fish-shellfish.


Asunto(s)
Calcio/administración & dosificación , Hierro/administración & dosificación , Dieta , Femenino , Humanos , Japón
19.
Intern Med ; 32(5): 412-5, 1993 May.
Artículo en Inglés | MEDLINE | ID: mdl-8400505

RESUMEN

A case of extramedullary plasmacytoma presenting with biclonal gammopathy is reported. The patient was an 82-year-old man in whom monoclonal-protein (M-protein) was not noted during his first hospitalization. On his second hospitalization generalized lymph node swelling and biclonal gammopathy (IgG-kappa, IgA-kappa) were observed. Histological findings were compatible with those of extramedullary plasmacytoma. In the terminal stages, the patient became cachexic. The autopsy disclosed dissemination of the plasmacytoma. Only two other cases have been reported in the literature, and a review of these previous reports is included.


Asunto(s)
Hipergammaglobulinemia/etiología , Plasmacitoma/complicaciones , Anciano , Anciano de 80 o más Años , Humanos , Hipergammaglobulinemia/inmunología , Masculino , Plasmacitoma/inmunología
20.
Jpn J Antibiot ; 42(5): 1065-76, 1989 May.
Artículo en Japonés | MEDLINE | ID: mdl-2664253

RESUMEN

One hundred ninety-eight patients with severe infections associated with hematopoietic disorders were treated with imipenem/cilastatin sodium (IPM/CS), and the efficacy and safety of the drug were evaluated. The results obtained are summarized below. 1. Out of 182 patients in whom efficacies are evaluable, responses were excellent in 50 patients, good in 52, fair in 21 and poor in 59, and the efficacy rating was 56.0%. 2. The efficacy rating in 87 patients who had failed to respond to prior treatment with other antibiotics was 58.6%. 3. There were significant differences in efficacy ratings when patients were grouped according to differences the number of neutrophils after treatment, less than 100, 101 approximately 500 and over 501/mm3. 4. The eradication rate in 38 patients from whom causative organisms were isolated was 75.8%. 5. Out of 197 patients in whom the safety was evaluable, side effects were observed in 19 patients (9.6%) and abnormal laboratory test values in 15 (7.6%).


Asunto(s)
Antibacterianos/uso terapéutico , Infecciones Bacterianas/tratamiento farmacológico , Cilastatina/uso terapéutico , Imipenem/uso terapéutico , Leucemia Mieloide Aguda/complicaciones , Linfoma/complicaciones , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/administración & dosificación , Infecciones Bacterianas/etiología , Cilastatina/administración & dosificación , Combinación Cilastatina e Imipenem , Ensayos Clínicos como Asunto , Combinación de Medicamentos/administración & dosificación , Combinación de Medicamentos/uso terapéutico , Femenino , Humanos , Imipenem/administración & dosificación , Infusiones Intravenosas , Recuento de Leucocitos , Masculino , Persona de Mediana Edad
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