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1.
Osteoarthritis Cartilage ; 28(6): 831-841, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32272195

RESUMEN

OBJECTIVE: Temporomandibular joint osteoarthritis (TMJOA) is a degenerative disease characterized by progressive cartilage degeneration, abnormal bone remodeling, and chronic pain. In this study, we aimed to investigate effective therapies to reverse or suppress TMJOA progression. DESIGN: To this end, we performed intravenous administration of serum free conditioned media from human exfoliated deciduous teeth stem cells (SHED-CM) into a mechanical-stress induced murine TMJOA model. RESULTS: SHED-CM administration markedly suppressed temporal muscle inflammation, and improved bone integrity and surface smoothness of the destroyed condylar cartilage. Moreover, SHED-CM treatment decreased the number of IL-1ß, iNOS, and MMP-13 expressing chondrocytes, whereas it specifically increased PCNA-positive cells in the multipotent polymorphic cell layer. Notably, the numbers of TdT-mediated dUTP nick end labeling (TUNEL)-positive apoptotic chondrocytes in the SHED-CM treated condyles were significantly lower than in those treated with DMEM, whereas the proteoglycan positive area was restored to a level similar to that of the sham treated group, demonstrating that SHED-CM treatment regenerated the mechanical-stress injured condylar cartilage and subchondral bone. Secretome analysis revealed that SHED-CM contained multiple therapeutic factors that act in osteochondral regeneration. CONCLUSIONS: Our data demonstrated that SHED-CM treatment promoted the regeneration and repair of mechanical-stress induced mouse TMJOA. Our observations suggest that SHED-CM has potential to be a potent tissue-regenerating therapeutic agent for patients with severe TMJOA.


Asunto(s)
Productos Biológicos/metabolismo , Productos Biológicos/uso terapéutico , Pulpa Dental/citología , Osteoartritis/terapia , Células Madre/metabolismo , Articulación Temporomandibular , Animales , Modelos Animales de Enfermedad , Humanos , Masculino , Ratones
2.
Br J Cancer ; 107(2): 340-4, 2012 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-22617127

RESUMEN

BACKGROUND: KRAS mutations are predictive markers for the efficacy of anti-EGFR antibody therapies in patients with metastatic colorectal cancer. Although the mutational status of KRAS is reportedly highly concordant between primary and metastatic lesions, it is not yet clear whether genotoxic chemotherapies might induce additional mutations. METHODS: A total of 63 lesions (23 baseline primary, 18 metastatic and 24 post-treatment metastatic) from 21 patients who were treated with FOLFOX as adjuvant therapy for stage III/IV colorectal cancer following curative resection were examined. The DNA samples were obtained from formalin-fixed paraffin-embedded specimens, and KRAS, NRAS, BRAF and PIK3CA mutations were evaluated. RESULTS: The numbers of primary lesions with wild-type and mutant KRAS codons 12 and 13 were 8 and 13, respectively. The mutational status of KRAS remained concordant between the primary tumours and the post-FOLFOX metastatic lesions, irrespective of patient background, treatment duration and disease-free survival. Furthermore, the mutational statuses of the other genes evaluated were also concordant between the primary and metastatic lesions. CONCLUSION: Because the mutational statuses of predictive biomarker genes were not altered by FOLFOX therapy, specimens from both primary tumours and post-FOLFOX tumour metastases might serve as valid sources of DNA for known genomic biomarker testing.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Mutación , Proteínas Proto-Oncogénicas/genética , Proteínas ras/genética , Adulto , Anciano , Biomarcadores de Tumor/genética , Fosfatidilinositol 3-Quinasa Clase I , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Supervivencia sin Enfermedad , Receptores ErbB/genética , Receptores ErbB/metabolismo , Femenino , Fluorouracilo/uso terapéutico , Genes ras , Humanos , Leucovorina/uso terapéutico , Masculino , Persona de Mediana Edad , Compuestos Organoplatinos/uso terapéutico , Fosfatidilinositol 3-Quinasas/genética , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas p21(ras)
3.
Diabetes Obes Metab ; 14(4): 379-82, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22098444

RESUMEN

In this 12-week, randomized, double-blind, placebo-controlled trial, the efficacy and safety of transglucosidase (TGD) were compared with placebo in patients with type 2 diabetes mellitus (T2DM). At 12 weeks, TGD 300 mg/day and TGD 900 mg/day significantly reduced HbA1c (0.18 and 0.21%) and insulin concentration (19.4 and 25.0 pmol/l), respectively, vs. placebo. TGD 300 mg/day and TGD 900 mg/day also significantly reduced low-density lipoprotein cholesterol (0.22 and 0.17 mmol/l, respectively). TGD 900 mg/day significantly reduced triglyceride by 0.24 mmol/l and diastolic blood pressure by 8 mmHg. Placebo was associated with a significant increase from baseline in body mass index, alanine aminotransferase and aspartate aminotransferase (0.17 kg/m(2) , 3 and 2 U/l, respectively), whereas TGD was not. TGD 300 mg/day significantly increased high-molecular-weight adiponectin by 0.6 µg/ml. Adverse events did not differ significantly between the groups. TGD resulted in lowering of HbA1c and blood insulin level and improvements in metabolic and cardiovascular risk factors in T2DM.


Asunto(s)
Glucemia/efectos de los fármacos , Enfermedades Cardiovasculares/etiología , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Glucosiltransferasas/uso terapéutico , Hipoglucemiantes/uso terapéutico , Hígado/efectos de los fármacos , Adiponectina/sangre , Alanina Transaminasa/sangre , Aspartato Aminotransferasas/sangre , Biomarcadores/sangre , Glucemia/metabolismo , Presión Sanguínea/efectos de los fármacos , Índice de Masa Corporal , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/tratamiento farmacológico , LDL-Colesterol/sangre , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/metabolismo , Método Doble Ciego , Femenino , Hemoglobina Glucada/metabolismo , Humanos , Insulina/sangre , Hígado/metabolismo , Masculino , Persona de Mediana Edad , Factores de Riesgo , Triglicéridos/sangre
4.
Br J Cancer ; 105(3): 403-6, 2011 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-21730978

RESUMEN

BACKGROUND: We aimed to compare the sensitive and quality-controlled KRAS testing with direct sequencing and to assess the impact on decision making of treatment. PATIENTS AND METHODS: We analysed genomic DNA isolated from macrodissected formalin-fixed paraffin-embedded specimens by direct sequencing and an amplification refractory mutation system-Scorpion assay (ARMS/S) method. Cetuximab was administered to patients identified as having wild-type (WT) KRAS using direct sequencing. Therapeutic effects were evaluated according to their KRAS status as determined by ARMS/S. RESULTS: Among the 159 patients, the overall mutation rate was determined to be 37.0% by direct sequencing and 44.0% by ARMS/S. For the patients diagnosed as WT by direct sequencing and treated with cetuximab (n=47), a response rate of 16.0% was observed for 38 ARMS/S WT patients, whereas 9 ARMS/S mutant (MUT) patients failed to respond. The ARMS/S WT patients showed significant improvement in progression-free survival (PFS) and overall survival (OS) compared with ARMS/S MUT patients (PFS median 5.0 vs 1.7 months, hazards ratio (HR)=0.29, P=0.001; OS median 12.1 vs 3.8 months, HR=0.26, P=0.001). CONCLUSION: Sensitive and quality-controlled KRAS testing may provide improved predictive power to determine the efficacy of anti-epidermal growth factor antibodies.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Análisis Mutacional de ADN/métodos , Genes ras , Mutación , Anciano , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales Humanizados , Cetuximab , Neoplasias Colorrectales/mortalidad , Supervivencia sin Enfermedad , Femenino , Humanos , Masculino , Análisis de Secuencia de ADN/métodos
5.
Methods Find Exp Clin Pharmacol ; 32(4): 243-6, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20508872

RESUMEN

Primary Helicobacter pylori eradication rate using triple therapy (a proton pump inhibitor [PPI] + amoxicillin [AMPC] + clarithromycin [CAM], over 7 days) is showing a declining trend. In this study we report recent eradication rates and have evaluated the usefulness of a pack preparation of three drugs. H. pylori eradication rate was 85.1% (57/67) in 2004 but then fell to 75.2% (79/105) in 2005, 70.1% (68/97) in 2006 and 69.9% (58/83) in 2007. With the introduction of packs (lansoprazole [LPZ] 60 mg, AMPC 1500 mg, CAM 400 mg) the eradication rate recovered to 78.0% (110/141) in 2008. A comparative study in 2008 delineated that the eradication rate in the pack group (88.4%, 38/43) was significantly higher than that of the conventional group (73.5%, 72/98). These results suggest that packs of eradication medicine are useful in increasing eradication success.


Asunto(s)
2-Piridinilmetilsulfinilbencimidazoles/uso terapéutico , Amoxicilina/uso terapéutico , Claritromicina/uso terapéutico , Infecciones por Helicobacter/tratamiento farmacológico , 2-Piridinilmetilsulfinilbencimidazoles/administración & dosificación , Adulto , Anciano , Amoxicilina/administración & dosificación , Antibacterianos/administración & dosificación , Antibacterianos/uso terapéutico , Antiulcerosos/administración & dosificación , Antiulcerosos/uso terapéutico , Claritromicina/administración & dosificación , Quimioterapia Combinada , Femenino , Infecciones por Helicobacter/microbiología , Helicobacter pylori/efectos de los fármacos , Helicobacter pylori/aislamiento & purificación , Humanos , Lansoprazol , Masculino , Persona de Mediana Edad , Inhibidores de la Bomba de Protones/administración & dosificación , Inhibidores de la Bomba de Protones/uso terapéutico , Estudios Retrospectivos
6.
Br J Cancer ; 100(8): 1320-9, 2009 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-19337254

RESUMEN

BCL6 is a transcriptional repressor that has important functions in lymphocyte differentiation and lymphomagenesis, but there have been no reports of BCL6 expression in gastric cancers. In the present study, we investigated the BCL6 function in gastric cancers. Treatment with TPA resulted in BCL6 degradation and cyclin D2 upregulation. This phenomenon was inhibited by the suppression of the nuclear translocation of HB-EGF-CTF (C-terminal fragment of pro-HB-EGF). The HB-EGF-CTF nuclear translocation leads to the interaction of BCL6 with HB-EGF-CTF and the nuclear export of BCL6, and after that BCL6 degradation was mediated by ubiquitin/proteasome pathway. Real-time RT-PCR and siRNA targeting BCL6 revealed that BCL6 suppresses cyclin D2 expression. Our data indicate that BCL6 interacts with nuclear-translocated HB-EGF-CTF and that the nuclear export and degradation of BCL6 induces cyclin D2 upregulation. We performed immunohistochemical analyses of BCL6, HB-EGF and cyclin D2 in human gastric cancers. The inverse correlation between BCL6 and cyclin D2 was also found in HB-EGF-positive human gastric cancers. BCL6 degradation caused by the HB-EGF-CTF also might induce cyclin D2 expression in human gastric cancers. Inhibition of HB-EGF-CTF nuclear translocation and maintenance of BCL6 function are important for the regulation of gastric cancer progression.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Represoras/metabolismo , Neoplasias Gástricas/genética , Anciano , Línea Celular Tumoral , Ciclina D2 , Ciclinas/genética , Receptores ErbB/metabolismo , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Invasividad Neoplásica , Metástasis de la Neoplasia , Fosforilación , Proteínas Proto-Oncogénicas/deficiencia , Proteínas Proto-Oncogénicas/genética , ARN Neoplásico/genética , ARN Interferente Pequeño/genética , Proteínas Represoras/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Neoplasias Gástricas/patología , Supresión Genética
7.
J Clin Invest ; 84(3): 1024-7, 1989 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2760209

RESUMEN

We report the identification of a female patient with the X-linked recessive Lesch-Nyhan syndrome (hypoxanthine phosphoribosyltransferase [HPRT] deficiency). Cytogenetic and carrier studies revealed structurally normal chromosomes for this patient and her parents and demonstrated that this mutation arose through a de novo gametic event. Comparison of this patient's DNA with the DNA of her parents revealed that a microdeletion, which occurred within a maternal gamete and involved the entire HPRT gene, was partially responsible for the disease in this patient. Somatic cell hybrids, generated to separate maternal and paternal X chromosomes, showed that expression of two additional X-linked enzymes, phosphoglycerate kinase and glucose-6-phosphate dehydrogenase, were expressed only in cells that contained the maternal X chromosome, suggesting the presence of a functionally inactive paternal X chromosome. Furthermore, comparison of methylation patterns within a region of the HPRT gene known to be important in gene regulation revealed differences between DNA from the father and the patient, in keeping with an active HPRT locus in the father and an inactive HPRT locus in the patient. Together these data indicate that nonrandom inactivation of the cytogenetically normal paternal X chromosome and a microdeletion of the HPRT gene on an active maternal X chromosome were responsible for the absence of HPRT in this patient.


Asunto(s)
Hipoxantina Fosforribosiltransferasa/deficiencia , Síndrome de Lesch-Nyhan/genética , Southern Blotting , Niño , Deleción Cromosómica , Femenino , Tamización de Portadores Genéticos , Ligamiento Genético , Humanos , Células Híbridas/enzimología , Hipoxantina Fosforribosiltransferasa/genética , Síndrome de Lesch-Nyhan/enzimología , Síndrome de Lesch-Nyhan/etiología , Masculino , Linaje , Cromosoma X
8.
Mol Cell Biol ; 9(5): 2244-6, 1989 May.
Artículo en Inglés | MEDLINE | ID: mdl-2568582

RESUMEN

AMP deaminase, a ubiquitous enzyme in eucaryotes, plays a central role in energy metabolism. In the present study, RNase protection analyses and immunoprecipitation with tissue-specific antisera were used to examine the transcripts and peptides of AMP deaminase produced during myogenesis in vivo and during myocyte differentiation in vitro. In embryonic muscle and undifferentiated myoblasts, a 3.4-kilobase (kb) transcript encoded a 78-kilodalton (kDa) AMP deaminase peptide that cross-reacted with antisera raised to the AMP deaminase isoform purified from kidney of the adult animal. In perinatal muscle and myocytes at an intermediate stage of differentiation in vitro, a 2.5-kb transcript was produced, and it encoded a 77.5-kDa AMP deaminase peptide that cross-reacted with antisera to the isoform purified from adult heart muscle. At about the time of birth, another 2.5-kb AMP deaminase transcript that encoded an 80-kDa peptide became detectable. This peptide cross-reacted with antisera to the predominant isoform purified from adult skeletal muscle.


Asunto(s)
AMP Desaminasa/genética , Músculos/enzimología , Nucleótido Desaminasas/genética , AMP Desaminasa/biosíntesis , Animales , Regulación de la Expresión Génica , Inmunoquímica , Desarrollo de Músculos , Poli A/genética , Sondas ARN , ARN Mensajero/genética , Ratas , Transcripción Genética
9.
Mol Cell Biol ; 13(8): 5043-56, 1993 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8336734

RESUMEN

We have reported the isolation of linking clones of HindIII and EcoRI fragments, altogether spanning a 230-kb continuous stretch of chromosome VI. The presence or absence of autonomously replicating sequence (ARS) activities in all of these fragments has been determined by using ARS searching vectors containing CEN4. Nine ARS fragments were identified, and their positions were mapped on the chromosome. Structures essential for and/or stimulative to ARS activity were determined for the ARS fragments by deletions and mutations. The organization of functional elements composed of core and stimulative sequences was found to be variable. Single core sequences were identified in eight of nine ARSs. The remaining ARS (ARS603) essential element is composed of two core-like sequences. The lengths of 3'- and 5'-flanking stimulative sequences required for the full activity of ARSs varied from ARS to ARS. Five ARSs required more than 100 bp of the 3'-flanking sequence as stimulative sequences, while not more than 79 bp of the 3' sequence was required by the other three ARSs. In addition, five ARSs had stimulative sequences varying from 127 to 312 bp in the 5'-flanking region of the core sequence. In general, these stimulative activities were correlated with low local delta Gs of unwinding, suggesting that the low local delta G of an ARS is an important element for determining the efficiency of initiation of replication of ARS plasmids.


Asunto(s)
Cromosomas Fúngicos/ultraestructura , Replicación del ADN , Saccharomyces cerevisiae/genética , Secuencia de Bases , Mapeo Cromosómico , Secuencia de Consenso , Análisis Mutacional de ADN , ADN de Hongos/genética , Datos de Secuencia Molecular , Oligonucleótidos/química , Mapeo Restrictivo , Eliminación de Secuencia
10.
Nucleic Acids Res ; 29(3): 683-92, 2001 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-11160890

RESUMEN

We used 2D protein gel electrophoresis and DNA microarray technologies to systematically analyze genes under glucose repression in B:acillus subtilis. In particular, we focused on genes expressed after the shift from glycolytic to gluconeogenic at the middle logarithmic phase of growth in a nutrient sporulation medium, which remained repressed by the addition of glucose. We also examined whether or not glucose repression of these genes was mediated by CcpA, the catabolite control protein of this bacterium. The wild-type and ccpA1 cells were grown with and without glucose, and their proteomes and transcriptomes were compared. 2D gel electrophoresis allowed us to identify 11 proteins, the synthesis of which was under glucose repression. Of these proteins, the synthesis of four (IolA, I, S and PckA) was under CcpA-independent control. Microarray analysis enabled us to detect 66 glucose-repressive genes, 22 of which (glmS, acoA, C, yisS, speD, gapB, pckA, yvdR, yxeF, iolA, B, C, D, E, F, G, H, I, J, R, S and yxbF ) were at least partially under CcpA-independent control. Furthermore, we found that CcpA and IolR, a repressor of the iol divergon, were involved in the glucose repression of the synthesis of inositol dehydrogenase encoded by iolG included in the above list. The CcpA-independent glucose repression of the iol genes appeared to be explained by inducer exclusion.


Asunto(s)
Bacillus subtilis/efectos de los fármacos , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Glucosa/farmacología , Proteoma , Secuencia de Aminoácidos , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Proteínas Bacterianas/efectos de los fármacos , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , División Celular/efectos de los fármacos , División Celular/genética , Medios de Cultivo/farmacología , Proteínas de Unión al ADN/efectos de los fármacos , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Electroforesis en Gel Bidimensional , L-Iditol 2-Deshidrogenasa/efectos de los fármacos , L-Iditol 2-Deshidrogenasa/genética , L-Iditol 2-Deshidrogenasa/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Proteínas Represoras/efectos de los fármacos , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Transcripción Genética
11.
Nucleic Acids Res ; 28(21): 4317-31, 2000 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-11058132

RESUMEN

The 4 202 353 bp genome of the alkaliphilic bacterium Bacillus halodurans C-125 contains 4066 predicted protein coding sequences (CDSs), 2141 (52.7%) of which have functional assignments, 1182 (29%) of which are conserved CDSs with unknown function and 743 (18. 3%) of which have no match to any protein database. Among the total CDSs, 8.8% match sequences of proteins found only in Bacillus subtilis and 66.7% are widely conserved in comparison with the proteins of various organisms, including B.subtilis. The B. halodurans genome contains 112 transposase genes, indicating that transposases have played an important evolutionary role in horizontal gene transfer and also in internal genetic rearrangement in the genome. Strain C-125 lacks some of the necessary genes for competence, such as comS, srfA and rapC, supporting the fact that competence has not been demonstrated experimentally in C-125. There is no paralog of tupA, encoding teichuronopeptide, which contributes to alkaliphily, in the C-125 genome and an ortholog of tupA cannot be found in the B.subtilis genome. Out of 11 sigma factors which belong to the extracytoplasmic function family, 10 are unique to B. halodurans, suggesting that they may have a role in the special mechanism of adaptation to an alkaline environment.


Asunto(s)
Bacillus subtilis/genética , Bacillus/genética , Genoma Bacteriano , Transportadoras de Casetes de Unión a ATP/genética , Adaptación Fisiológica/genética , Álcalis/metabolismo , Bacillus/química , Bacillus/clasificación , Bacillus/metabolismo , Bacillus subtilis/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/fisiología , Composición de Base , Transporte Biológico , Pared Celular/genética , Pared Celular/metabolismo , Secuencia Conservada/genética , Elementos Transponibles de ADN/genética , Bases de Datos como Asunto , Metabolismo Energético , Evolución Molecular , Transferencia de Gen Horizontal/genética , Genes Bacterianos/genética , Genes Bacterianos/fisiología , Datos de Secuencia Molecular , Sistemas de Lectura Abierta/genética , Mapeo Físico de Cromosoma , Biosíntesis de Proteínas , ARN de Transferencia/genética , Origen de Réplica/genética , Homología de Secuencia , Factor sigma/genética , Esporas Bacterianas/genética , Transcripción Genética/genética , Transposasas/genética
12.
Biochim Biophys Acta ; 717(3): 439-44, 1982 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-7126639

RESUMEN

Three trypsinogens and one chymotrypsinogen were found in and purified from the pancreas of a mouse strain (CFO). The molecular weights of the trypsinogens and the chymotrypsinogen were all estimated as 25 000. The enzyme properties of the three trypsinogens were studied and they showed very low Km values (3.2-6.5 microM) for the substrates, Bz-Arg-OEt and Tos-Arg-OMe, and the same pH optimum profile between pH 8.0-10.0. However, the ratios of catalytic rate constants, kcat (s-1), with Bz-Arg-OEt as substrates compared to that with Tos-Arg-OMe were very different. The values of Try-III were similar with the two substrates, Try-I was slightly higher value with Tos-Arg-OMe than with Bz-Arg-OEt, and the values of Try-II were much higher with Tos-Arg-OMe than with Bz-Arg-OEt. Also, the trypsinogens and the chymotrypsinogen were purified from pancreas of Mol-A strain mice. When the enzyme properties of the three trypsinogens were examined, one form of trypsinogen (Try-I) was shown to have different properties in kcat (s-1) for the two substrates, compared to the trypsinogen of CFO mice.


Asunto(s)
Quimotripsinógeno/aislamiento & purificación , Páncreas/enzimología , Tripsinógeno/aislamiento & purificación , Animales , Fenómenos Químicos , Química , Cromatografía DEAE-Celulosa , Cromatografía en Gel , Ratones , Ratones Endogámicos
13.
Biochim Biophys Acta ; 1171(1): 125-8, 1992 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-1420359

RESUMEN

The nucleotide sequence of cDNA encoding human erythrocyte AMP deaminase has been determined by screening of human spleen cDNA library and by utilizing polymerase chain reaction (PCR) techniques. The 3.7 kb cDNA contains an open reading frame of 2301 bp which encodes 767 amino acids chain resulting in 89 kDa protein. The polyadenylation consensus signal (5'-AATAAA) located at 1212 bp 3' downstream from the stop codon. The homologies to human and rat muscle-specific AMP deaminases showed 64.1% and 65.2% identities, respectively, at the nucleotide level in the area of open reading frame, and 60.2% and 59.8% similarities at the deduced amino acid level.


Asunto(s)
AMP Desaminasa/genética , ADN , Eritrocitos/enzimología , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , Codón , Humanos , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Reacción en Cadena de la Polimerasa , Mapeo Restrictivo
14.
Biochim Biophys Acta ; 761(1): 34-40, 1983 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-6315069

RESUMEN

Purine nucleoside kinases in human B- and T-lymphoblasts were fractionated by DEAE-cellulose chromatography. Human B-lymphoblast cell extracts showed three peaks of nucleoside kinase activities, adenosine kinase (EC 2.7.1.20), deoxyguanosine kinase and deoxycytidine kinase (EC 2.7.1.74). However, T-lymphoblast cell extracts showed a nucleoside kinase activity which phosphorylates deoxycytidine, deoxyadenosine and deoxyguanosine, similar to deoxycytidine kinase, in addition to the three nucleoside kinases. The Km values of T-lymphoblast-specific nucleoside kinase for deoxyadenosine and deoxyguanosine, 15 and 26 microM, respectively, were smaller than those of deoxycytidine kinase, 150 and 330 microM, respectively. Deoxyadenosine phosphorylation by deoxycytidine kinase was strongly inhibited by dCTP, but the phosphorylation by T-lymphoblast-specific nucleoside kinase was only weakly inhibited by dCTP. Deoxyadenosine phosphorylating activity in B-lymphoblast extracts was more distinctly inhibited by dCTP than that in T-lymphoblast extracts.


Asunto(s)
Linfocitos B/enzimología , Fosfotransferasas (Aceptor de Grupo Alcohol) , Fosfotransferasas/metabolismo , Nucleósidos de Purina/metabolismo , Linfocitos T/enzimología , Adenosina Quinasa/metabolismo , Línea Celular , Cromatografía DEAE-Celulosa , Desoxicitidina Quinasa/metabolismo , Humanos , Cinética
15.
Biochim Biophys Acta ; 616(2): 199-207, 1980 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-6260151

RESUMEN

Adenosine kinase (ATP:adenosine 5'-phosphotransferase, EC 2.7.1.20) has been purified to apparent homogeneity from rat brain by (NH4)2SO4 fractionation, affinity chromatography on AMP-Sepharose 4B, gel filtration with Sephadex G-100, and DE-52 cellulose column chromatography. The yield was 56% of the initial activity with a final specific activity of 7.8 mumol/min per mg protein. The molecular weight was estimated as 38 000 by gel filtration with Sephadex G-100 and 41 000 by acrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS). The enzyme catalyzed the phosphorylation of adenosine, deoxyadenosine, arabinoadenosine, inosine and ribavirin. The activity of deoxyadenosine phosphorylation was 20% that of adenosine phosphorylation. The pH optimum profile was biphasic; a sharp pH optimum at pH 5.5 and a broad pH optimum at pH 7.5-8.5. The Km value for adenosine was 0.2 microM and the maximum activity was observed at 0.5 microM. At higher concentrations of adenosine, the activity was strongly inhibited. The Km value for ATP was 0.02 mM and that for Mg2+ was 0.1 mM. GTP, dGTP, dATP and UTP were also proved to be effective phosphate donors. Co2+ was as effective as Mg2+, and Ca2+, Mn2+ or Ni2+ showed about 50% of the activity for Mg2+. The kinase is quite unstable, but stable in the presence of a high concentration of salt; e.g., 0.15 M KCl.


Asunto(s)
Adenosina Quinasa/metabolismo , Encéfalo/enzimología , Fosfotransferasas/metabolismo , Adenosina Quinasa/aislamiento & purificación , Adenosina Trifosfato/farmacología , Animales , Desoxiadenosinas , Concentración de Iones de Hidrógeno , Técnicas In Vitro , Cinética , Magnesio/farmacología , Peso Molecular , Ratas , Especificidad por Sustrato
16.
Biochim Biophys Acta ; 524(2): 442-6, 1978 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-208624

RESUMEN

Purified rat muscle AMP deaminase (AMP aminohydrolase, EC 3.5.4.6) binds tightly to rat myosin. The binding is abolished in the presence of low concentrations of various ligands. Pyrophosphate and GTP at concentrations as low as 0.1 micrometer were effective in abolishing the interaction between two proteins. Other nucleoside triphosphates were less effective than GTP and the concentrations required for 50% inhibition were approximately 0.3 to 0.7 micrometer. ADP and AMP are effective in inhibiting the interaction between two proteins, but they are less effective than the nucleoside triphosphates; 50% inhibition occurred at 34 micrometer with ADP and at 1 mM with AMP. Creatine phosphate and inorganic phosphate showed 50% inhibition at 5 to 6 mM. All of the compounds, which affected AMP deaminase activity, were effective in abolishing the interaction of the enzyme with myosin; however, the interaction-abolishing effects of the compounds are not parallel with their inhibitory effects on the deaminase activity. Although there exist three parental isozymes of AMP deaminase in the rat, all three enzymes interacted with myosin.


Asunto(s)
AMP Desaminasa , Miosinas , Nucleótido Desaminasas , Animales , Difosfatos , Guanosina Trifosfato , Cinética , Ligandos , Músculos/enzimología , Unión Proteica , Ratas
17.
Biochim Biophys Acta ; 403(2): 530-7, 1975 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-1182154

RESUMEN

Three AMP deaminase isozymes (EC 3.5.4.6 AMP aminohydrolase) were purified from rat heart, kidney and muscle. These enzyme preparations contained only the required isozyme. Antisera to individual isozymes were prepared and immunological relationships were tested. There was no cross-reactivity as tested by precipitation experiments. The antisera precipitated only the corresponding isozyme and there was no effect on other isozymes. These isozymes were also different in Km values for AMP and in substrate specificity. From the present studies, combined with previous results, it seems clear that the heart, kidney and muscle enzymes are different basic types. It is proposed that the muscle enzyme be designated as AMP deaminase A; the enzyme in kidney and liver, AMP deaminase B; the enzyme in heart, AMP deaminase C. Brain extracts contained five isozymes; two parent isozymes (B and C) and presumably their three hybrids.


Asunto(s)
AMP Desaminasa/metabolismo , Isoenzimas/metabolismo , Riñón/enzimología , Músculos/enzimología , Miocardio/enzimología , Nucleótido Desaminasas/metabolismo , AMP Desaminasa/inmunología , AMP Desaminasa/aislamiento & purificación , Animales , Encéfalo/enzimología , Isoenzimas/inmunología , Isoenzimas/aislamiento & purificación , Cinética , Especificidad de Órganos , Pruebas de Precipitina , Ratas
18.
Biochim Biophys Acta ; 709(2): 265-72, 1982 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-6295492

RESUMEN

Deoxyguanosine kinase (ATP:deoxyguanosine 5'-phosphotransferase) has been purified up to a specific activity of 10.3 nmol/min per mg protein from human placenta. The enzyme appears to have a molecular weight of 58 000 from the results of Sephadex G-75 gel filtration. The enzyme catalyzed phosphorylation of deoxyguanosine and deoxyadenosine, but deoxycytidine was not phosphorylated. An apparent Km value for deoxyguanosine was 2.5 micro M. When ATP was used as a phosphate donor, the pH optimum was at pH 6.0, but the optimum was shifted to pH 6.8 by the addition of dTTP. At physiological pH, the activity was stimulated 3-4-fold by dTTP. dTTP was also an effective phosphate donor, but using dTTP as a phosphate donor, a broad pH optimum of 7.0 was observed. Two Km values of 0.13 and 2.2 mM were obtained for both MgATP2- and MgdTTP2-. The activity was strongly inhibited by dGTP and dGDP; 50% inhibition by 1.0 micro M dGTP and 2.1 micro M dGDP, respectively. The enzyme required the presence o Mg2+ or Mn2+.


Asunto(s)
Fosfotransferasas (Aceptor de Grupo Alcohol) , Fosfotransferasas/metabolismo , Placenta/enzimología , Cationes Bivalentes , Femenino , Humanos , Concentración de Iones de Hidrógeno , Cinética , Peso Molecular , Fosfotransferasas/aislamiento & purificación , Embarazo , Especificidad por Sustrato
19.
Biochim Biophys Acta ; 660(1): 36-43, 1981 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-6268173

RESUMEN

Adenosine kinase (ATP: adenosine 5'-phosphotransferase, EC 2.7.1.20) has been purified to homogeneity from human liver. The yield was 55% of the initial activity with a final specific activity of 6.3 mumol/min per mg protein. The molecular weight was estimated as about 40 000 by Sephadex G-100 gel filtration and polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS). The enzyme catalyzed the phosphorylation of adenosine, deoxyadenosine, arabinoadenosine, inosine and ribavirin. The activity of deoxyadenosine phosphorylation was 18% of that of adenosine. The pH optimum profile was biphasic; a sharp pH optimum at pH 5.5 and a broad optimum at pH 7.5--8.5. The Km value for adenosine was 0.15 micrometer, and the activity was strongly inhibited at higher concentrations than 0.5 micrometer. ATP, dATP, GTP and dGTP were proved to be effective phosphate donors. Co2+ was more effective than Mg2+, and Ca2+, Mn2+, Fe2+ and Ni2+ showed about 50% of the activity for Mg2+. Some difference in structure between the adenosine kinase from human liver and that from rabbit or rat tissue, was observed by amino acid analysis and peptide mapping analysis.


Asunto(s)
Adenosina Quinasa/metabolismo , Hígado/enzimología , Fosfotransferasas (Aceptor de Grupo Alcohol) , Fosfotransferasas/metabolismo , Adenosina Quinasa/aislamiento & purificación , Animales , Cationes Bivalentes/farmacología , Fenómenos Químicos , Química , Humanos , Concentración de Iones de Hidrógeno , Nucleótidos/metabolismo , Fragmentos de Péptidos , Conejos , Ratas , Especificidad de la Especie , Especificidad por Sustrato
20.
Biochim Biophys Acta ; 661(1): 164-9, 1981 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-6170336

RESUMEN

tRNA, 18 S and 28 S ribosomal RNAs were found to activate muscle AMP deaminase (AMP aminohydrolase, EC 3.5.4.6) but inhibit liver and heart AMP deaminases. The macromolecular structures are essential for modulation of enzyme activity, since the effects of RNA disappeared after RNAase treatment. Sucrose density centrifugation experiments clearly demonstrated the binding of purified muscle AMP deaminase to tRNA, 18 S and 28 S RNAs. The binding is reversible and responsive to alterations of pH and KCl concentration. The binding was stable at pH 5.1-7.0 in 0.1 M KCl, but most of the enzyme dissociated at pH 7.5. KCl below 0.1 M concentration had no effect on dissociation of enzyme-RNA complex, but in 0.15 M KCl the complex was partially dissociated and in 0.2 M KCl most of the enzyme was released. Various nucleotides were also effective in dissociation of the enzyme from complex. The binding is saturable and the maximum number of muscle AMP deaminase molecules bound per mol 28 S RNA was calculated to be approx. 30. Liver and heart AMP deaminases were also found to interact with RNA.


Asunto(s)
AMP Desaminasa/metabolismo , Nucleótido Desaminasas/metabolismo , ARN/metabolismo , Animales , Técnicas In Vitro , Isoenzimas/metabolismo , Cinética , Hígado/metabolismo , Músculos/metabolismo , Miocardio/metabolismo , Nucleótidos/farmacología , ARN/farmacología , ARN Ribosómico/metabolismo , ARN de Transferencia/metabolismo , Ratas
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