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1.
Head Neck ; 40(4): 846-854, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29155470

RESUMEN

BACKGROUND: Indications for treatment and outcomes after endovascular management of carotid blowout syndrome for patients with head and neck cancer are not well defined. We investigated the safety and effectiveness of endovascular embolization and stent-graft reconstruction. METHODS: A literature review was performed for studies published between 2001 and 2015 with relevance to treatment outcomes. Our institutional database was examined to identify patients treated with endovascular techniques. RESULTS: A total of 266 patients were included. Rates of procedural stroke were higher after embolization of internal carotid artery (ICA)/common carotid artery (CCA) compared to stent graft (embolization 10.3%; stent graft 2.5%; P < .02). Stent graft of ICA/CCA was associated with higher rates of recurrent bleeding (embolization 9.1%; stent graft 31.9%; P < .01). CONCLUSION: Both embolization and stent grafts are safe therapeutic options for acute carotid blowout syndrome. Embolization for ICA/CCA carotid blowout syndrome was associated with higher risks of procedural stroke and lower recurrent bleeding compared to stent grafts.


Asunto(s)
Enfermedades de las Arterias Carótidas/terapia , Embolización Terapéutica/métodos , Procedimientos Endovasculares/métodos , Neoplasias de Cabeza y Cuello/cirugía , Disección del Cuello/efectos adversos , Stents , Enfermedad Aguda , Adulto , Anciano , Enfermedades de las Arterias Carótidas/etiología , Arteria Carótida Común/fisiopatología , Arteria Carótida Interna/fisiopatología , Femenino , Neoplasias de Cabeza y Cuello/patología , Humanos , Masculino , Persona de Mediana Edad , Disección del Cuello/métodos , Estudios Observacionales como Asunto , Medición de Riesgo , Rotura Espontánea/etiología , Rotura Espontánea/terapia , Síndrome , Resultado del Tratamiento
2.
Comp Biochem Physiol B Biochem Mol Biol ; 163(1): 96-100, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22580267

RESUMEN

In the oyster Crassostrea gigas consumption-related traits, amylase properties and growth were found to be linked through genotypes that differed for polymorphism in the two amylase genes AMYA and AMYB. Modulation of AMYA mRNA level had already been observed in response to food availability, whereas the functional role of AMYB was still unknown. To improve knowledge about the regulation of amylase expression in C. gigas and the respective roles of the two genes, we made an assay of amylase expression at mRNA and enzymatic levels in the digestive gland of oysters that had received dietary supplements of starch. After 18 days, a significant increase of translatable mRNA for AMYB was observed, with a correlated increase in Michaelis-Menten constant Km values and a decrease in total amylase activity. This modulation is the first evidence of observable functioning of AMYB in digestive processes. Amylase B is suggested to display a higher Km than amylase A, offering a means of adapting to high substrate concentrations. The highest starch supplement level (10 mgL(-1)) induced alteration in oyster physiology. The 1 mgL(-1) treatment should be tested as a practical food supplement that could lead to growth benefits for oysters.


Asunto(s)
Amilasas/genética , Amilasas/metabolismo , Crassostrea/enzimología , Almidón/farmacología , Animales , Crassostrea/efectos de los fármacos , Crassostrea/genética , Activación Enzimática/efectos de los fármacos , Activación Enzimática/genética , ARN Mensajero/genética
3.
Anim Genet ; 39(6): 662-5, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18717666

RESUMEN

To examine further a previously reported association between amylase gene polymorphism and growth in the Pacific oyster Crassostrea gigas, ecophysiological parameters and biochemical and molecular expression levels of alpha-amylase were studied in Pacific oysters of different amylase genotypes. Genotypes that previously displayed significantly different growth were found to be significantly different for ingestion and absorption efficiency. These estimated parameters, used in a dynamic energy budget model, showed that observed ingestion rates (unlike absorption efficiencies) allowed an accurate prediction of growth potential in these genotypes. The observed association between growth and amylase gene polymorphism is therefore more likely to be related to ingestion than to absorption efficiency. Additionally, relative mRNA levels of the two amylase cDNAs were also strongly associated with amylase gene polymorphism, possibly reflecting variation in an undefined regulatory region, although no corresponding variation was observed in specific amylase activity. Amylase gene sequences were determined for each genotype, showing the existence of only synonymous or functionally equivalent non-synonymous polymorphisms. The observed associations among growth, food consumption-related traits and amylase gene polymorphism are therefore more likely to be related to variation in the level of amylase gene expression than to functional enzymatic variants.


Asunto(s)
Amilasas/genética , Conducta Alimentaria , Ostreidae/genética , Polimorfismo Genético , Amilasas/metabolismo , Animales , Secuencia de Bases , Cartilla de ADN , Cinética , Ostreidae/enzimología , Ostreidae/fisiología , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción
4.
Anim Genet ; 37(4): 348-51, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16879344

RESUMEN

This study investigated the non-neutrality of genetic polymorphism in two alpha-amylase genes (AMYA and AMYB) in the oyster Crassostrea gigas. Bi-parental oyster families, bred to be polymorphic for markers in these genes, were monitored for growth and survival for 1 year under standard culture conditions in two French production sites. Within-family genotype frequencies indicated that the two amylase genes were closely linked (c. 1.7 cM). Within two of three families, significant differences in growth were observed between genotypes at one of the two production sites, suggesting that this polymorphism is not neutral and might be under selection because of its role in digestive function. Estimated daily yields were different between amylase genotypes, indicating the potential value of amylase markers in selective breeding programmes to improve oyster growth.


Asunto(s)
Crassostrea/crecimiento & desarrollo , Crassostrea/genética , Polimorfismo Genético , alfa-Amilasas/genética , Animales , Cruzamiento , Francia , Marcadores Genéticos , Genotipo
5.
Genomics ; 87(1): 84-92, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16314073

RESUMEN

Congenital erythropoietic porphyria (CEP) is a recessive autosomal disorder characterized by a deficiency in uroporphyrinogen III synthase (UROS), the fourth enzyme of the heme biosynthetic pathway. The severity of the disease, the lack of specific treatment except for allogeneic bone marrow transplantation, and the knowledge of the molecular lesions are strong arguments for gene therapy. An animal model of CEP has been designed to evaluate the feasibility of retroviral gene transfer in hematopoietic stem cells. We have previously demonstrated that the knockout of the Uros gene is lethal in mice (Uros(del) model). This work describes the achievement of a knock-in model, which reproduces a mutation of the UROS gene responsible for a severe UROS deficiency in humans (P248Q missense mutant). Homozygous mice display erythrodontia, moderate photosensitivity, hepatosplenomegaly, and hemolytic anemia. Uroporphyrin (99% type I isomer) accumulates in urine. Total porphyrins are increased in erythrocytes and feces, while Uros enzymatic activity is below 1% of the normal level in the different tissues analyzed. These pathological findings closely mimic the CEP disease in humans and demonstrate that the Uros(mut248) mouse represents a suitable model of the human disease for pathophysiological, pharmaceutical, and therapeutic purposes.


Asunto(s)
Sustitución de Aminoácidos , Mutación Missense , Porfiria Eritropoyética/enzimología , Uroporfirinógeno III Sintetasa/genética , Animales , Trasplante de Médula Ósea , Modelos Animales de Enfermedad , Terapia Genética , Ratones , Ratones Transgénicos , Porfiria Eritropoyética/patología , Porfiria Eritropoyética/terapia , Uroporfirinógeno III Sintetasa/metabolismo , Uroporfirinas/metabolismo
6.
Comp Biochem Physiol B Biochem Mol Biol ; 140(4): 635-46, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15763519

RESUMEN

To investigate the control at the mRNA level of glycogen metabolism in the cupped oyster Crassostrea gigas, we report in the present paper the cloning and characterization of glycogen phosphorylase and synthase cDNAs (Cg-GPH and Cg-GYS, respectively, transcripts of main enzymes for glycogen use and storage), and their first expression profiles depending on oyster tissues and seasons. A strong expression of both genes was observed in the labial palps and the gonad in accordance with specific cells located in both tissues and ability to store glucose. Cg-GPH expression was also found mainly in muscle suggesting ability to use glycogen as readily available glucose to supply its activity. For seasonal examinations, expression of Cg-GYS and Cg-GPH genes appeared to be regulated according to variation in glycogen content. Relative levels of Cg-GYS transcripts appeared highest in October corresponding to glycogen storage and resting period. Relative levels of Cg-GPH transcripts were highest in May corresponding to mobilization of glycogen needed for germ cell maturation. Expression of both genes would likely be driven by the oyster's reproductive cycle, reflecting the central role of glycogen in energy storage and gametogenic development in C. gigas. Both genes are useful molecular markers in the regulation of glycogen metabolism and reproduction in C. gigas but enzymatic regulation of glycogen phosphorylase and synthase remains to be elucidated.


Asunto(s)
Regulación Enzimológica de la Expresión Génica , Glucógeno Fosforilasa/genética , Glucógeno Sintasa/genética , Ostreidae/enzimología , Secuencia de Aminoácidos , Animales , Clonación Molecular , ADN Complementario/genética , ADN Complementario/aislamiento & purificación , Glucógeno Fosforilasa/aislamiento & purificación , Glucógeno Sintasa/aislamiento & purificación , Datos de Secuencia Molecular , Filogenia , Estaciones del Año , Alineación de Secuencia , Distribución Tisular
7.
Biochem Biophys Res Commun ; 320(2): 592-8, 2004 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-15219870

RESUMEN

The oyster vasa-like gene was previously demonstrated to be specifically expressed in germline cells of adult oysters Crassostrea gigas. In the present study, this gene was used as a molecular marker to establish the developmental pattern of germline cells during oyster ontogenesis, using whole-mount in situ hybridization and real-time PCR. The Oyvlg transcripts appeared to be localized to the vegetal pole of unfertilized oocytes and maternally transmitted to embryos. At early development, these maternal transcripts were observed to segregate into a single blastomere, from the CD macromere of 2-cell stage to the 4d mesentoblast of blastula. From late blastula stage, the mesentoblast divided into two cell clumps that migrated to both sides of the larvae body and that would correspond to primordial germ cells (PGCs). Based on these results, we postulate that the germline of C. gigas is specified at early development by maternal cytoplasmic determinants including Oyvlg mRNAs, in putative PGCs that would differentiate into germinal stem cells in juvenile oysters.


Asunto(s)
Biomarcadores , Genes , Células Germinativas , Ostreidae/embriología , Animales , Secuencia de Bases , Cartilla de ADN , Femenino , Hibridación in Situ/métodos , Masculino , Ostreidae/genética , Reacción en Cadena de la Polimerasa/métodos , ARN Mensajero/genética
8.
Placenta ; 25(1): 20-8, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15013635

RESUMEN

NDP kinases are the non-specific enzymes which catalyse the synthesis of the NTPs through a transfer reaction using ATP as phosphoryl donor. In addition to their enzymatic activity, they display other not yet explained functions related to cell growth, differentiation and apoptosis, embryonic development, tumour progression and metastasis. In this study, the expression patterns of the three highly related NDP kinases A, B and C isoforms were investigated in the developing human trophoblast. Both NDP kinase A and B were found to be primarily present in the villous and extravillous cytotrophoblasts, while NDP kinase C was found almost exclusively in the syncytiotrophoblast layer. This suggests that NDP kinase A and B could be a marker for the mononuclear stage of differentiation of villous trophoblasts, while NDP kinase C could be a marker of the syncytiotrophoblast layer.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica/genética , Nucleósido-Difosfato Quinasa/genética , Trofoblastos/enzimología , Desarrollo Embrionario y Fetal/fisiología , Proteínas del Ojo/metabolismo , Femenino , Edad Gestacional , Humanos , Inmunohistoquímica , Hibridación in Situ , Antígeno Ki-67/análisis , Nucleósido Difosfato Quinasas NM23 , Proteínas del Tejido Nervioso/metabolismo , Nucleósido-Difosfato Quinasa/metabolismo , Embarazo
9.
J Bioenerg Biomembr ; 35(1): 19-30, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12848338

RESUMEN

Mice carrying a homozygous germ-line mutation in the nm23-M1 gene that eliminates its protein expression and drives expression of beta-galactosidase by nm23-M1 promoter have been generated. nm23-M1 gene inactivation is not teratogenic and the pups can grow to adult age without apparent health problems. However, they undergo a growth retardation and knocked out females cannot feed their pups. Both effects are background dependent. Beta-galactosidase mapping of nm23-M1 promoter activation during embryogenesis shows that the nm23-M1 gene is principally expressed in epithelial layer of tissues which require inductive epithelial-mesenchymal interactions for their formation. In conclusion, invalidated mice could be interesting models to analyze the role of nm23-M1 on signal transduction pathway regulation, or cancer induction and proliferation.


Asunto(s)
Mama/metabolismo , Retardo del Crecimiento Fetal/genética , Regulación del Desarrollo de la Expresión Génica/genética , Regulación Enzimológica de la Expresión Génica/genética , Modelos Animales , Nucleósido-Difosfato Quinasa , Proteínas/genética , Proteínas/metabolismo , Animales , Animales Recién Nacidos , Clonación Molecular , Femenino , Retardo del Crecimiento Fetal/metabolismo , Ratones , Ratones Noqueados/embriología , Ratones Noqueados/crecimiento & desarrollo , Ratones Noqueados/metabolismo , Nucleósido Difosfato Quinasas NM23 , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transducción de Señal/genética , Relación Estructura-Actividad
10.
Mar Biotechnol (NY) ; 5(4): 360-72, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14719164

RESUMEN

Using the previously determined complementary DNA Sequence of Crassostrea gigas amylase (Y08370), we designed several oligonucleotide primers and used them with polymerase chain reaction (PCR) technology to characterize oyster amylase gene sequences. Two genes encoding 2 different amylases were characterized and sequenced. The 2 genes are similarly organized with 8 exons and 7 introns. Intron insertions are found at the same location in the 2 genes. Sizes and nucleotide sequences are different for the different introns inside each gene and different for the corresponding introns in the 2 genes. Comparing the 2 genes, around 10% of the nucleotides are different along the exons, and comparing the 2 deduced protein sequences, a mean value of 10.4% of amino acids are changed. Genes A and B encode mature proteins of, respectively, 500 and 499 amino acids, which present 94% similarity. A microsatellite (TC(37)) that constitutes the largest part of intron 4 of gene A has been used as a polymorphic marker. A method consisting of a PCR step followed by EcoRI digestion of the obtained fragments was used to observe polymorphism in these 2 genes. Six and 4 alleles for genes A and B, respectively, have been sequenced, leading to a maximum of 2.9% base change. The 2 genes are ubiquitously expressed in the different digestive tissues with quantitative differences. Gene A is strongly expressed in the digestive gland and at a lower level in stomach, while gene B is preferentially expressed in the labial palps. The microsatellite repeat was used in the analysis of 4 populations of Crassostrea gigas from the French Atlantic coast. A high level of polymorphism observed with 30 different alleles of gene A inside the populations should allow their characterization using the mean value of the microsatellite allelic distribution. These populations showed a low level of differentiation ( F(st) between 0 and 0.011); however, the population of Bonne Anse appeared to be distinguished from the other populations.


Asunto(s)
Alelos , Amilasas/genética , Genética de Población , Ostreidae/genética , Polimorfismo Genético , Animales , Secuencia de Bases , Mapeo Cromosómico , Cartilla de ADN , ADN Complementario/genética , Francia , Perfilación de la Expresión Génica , Frecuencia de los Genes , Datos de Secuencia Molecular , Polimorfismo de Longitud del Fragmento de Restricción , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN
11.
Gene ; 296(1-2): 87-97, 2002 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-12383506

RESUMEN

The nm23 gene family is thought to be involved in physiopathological processes such as growth, differentiation and cancer promotion, progression or metastasis. We report here the mouse nm23-M3 and nm23-M4 complementary DNA sequences and the genomic cloning, characterization and tissue expression pattern of the nm23-M2, nm23-M3 and nm23-M4 genes, in comparison with their human and rat orthologs and with the human nm23-H1 and mouse nm23-M1 genes. The organization and structure of the members of this gene family are remarkably similar in human and rodents. Accordingly, the striking similarities between the human and mouse nm23 genes enable the use of mouse transgenic and knock-out models for studying the role of nucleoside diphosphate kinase isoforms in human physiopathology.


Asunto(s)
Proteínas de Unión al GTP Monoméricas/genética , Nucleósido-Difosfato Quinasa/genética , Factores de Transcripción/genética , Secuencia de Aminoácidos , Animales , Northern Blotting , Clonación Molecular , ADN/química , ADN/genética , ADN Complementario/química , ADN Complementario/genética , Embrión de Mamíferos/enzimología , Embrión de Mamíferos/metabolismo , Exones , Regulación del Desarrollo de la Expresión Génica , Regulación Enzimológica de la Expresión Génica , Genes/genética , Humanos , Hibridación in Situ , Intrones , Isoenzimas/genética , Ratones , Datos de Secuencia Molecular , Nucleósido Difosfato Quinasas NM23 , ARN Mensajero/genética , ARN Mensajero/metabolismo , Alineación de Secuencia , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Sitio de Iniciación de la Transcripción
12.
Br J Cancer ; 86(1): 117-22, 2002 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-11857022

RESUMEN

Neuroblastoma and its benign differentiated counterpart, ganglioneuroma, are paediatric neuroblastic tumours arising in the sympathetic nervous system. Their broad spectrum of clinical virulence is mainly related to heterogeneous biologic background and tumour differentiation. Neuroblastic tumours synthesize various neuropeptides acting as neuromodulators. Previous studies suggested that galanin plays a role in sympathetic tissue where it could be involved in differentiation and development. We investigated the expression and distribution of galanin and its three known receptors (Gal-R1, Gal-R2, Gal-R3) in 19 samples of neuroblastic tumours tissue by immunohistochemistry, in situ hybridization and fluorescent-ligand binding. This study provides clear evidence for galanin and galanin receptor expression in human neuroblastic tumours. The messengers coding for galanin, Gal-R1 and -R3 were highly expressed in neuroblastoma and their amount dramatically decreased in ganglioneuroma. In contrast, Gal-R2 levels remained unchanged. Double labelling studies showed that galanin was mainly co-expressed with its receptors whatever the differentiation stage. In neuroblastic tumours, galanin might promote cell-survival or counteract neuronal differentiation through the different signalling pathways mediated by galanin receptors. Finally, our results suggest that galanin influences neuroblastoma growth and development as an autocrine/paracrine modulator. These findings suggest potential critical implications for galanin in neuroblastic tumours development.


Asunto(s)
Galanina/análisis , Neuroblastoma/química , Receptores de Neuropéptido/análisis , Diferenciación Celular , Niño , Preescolar , Femenino , Galanina/metabolismo , Humanos , Inmunohistoquímica , Lactante , Masculino , Neuroblastoma/patología , Receptores de Galanina
13.
Hepatology ; 32(1): 73-81, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10869291

RESUMEN

Erythropoietic protoporphyria (EPP) is characterized clinically by cutaneous photosensitivity and biochemically by the accumulation of excessive amounts of protoporphyrin in erythrocytes, plasma, feces, and other tissues, such as the liver. The condition is inherited as an autosomal dominant or recessive trait, with a deficiency of ferrochelatase activity. A major concern in EPP patients is the development of cholestasis with accumulation of protoporphyrin in hepatobiliary structures and progressive cellular damage, which can rapidly lead to fatal hepatic failure. The availability of a mouse model for the disease, the Fech(m1Pas)/Fech(m1Pas) mutant mouse, allowed us to test a cellular therapy protocol to correct the porphyric phenotype. When Fech/Fech mice received bone marrow cells from normal animals, the accumulation of protoporphyrin in red blood cells and plasma was reduced 10-fold but still remained 2.5 times above normal levels. Interestingly, in very young animals, bone marrow transplantation can prevent hepatobiliary complications as well as hepatocyte alterations and partially reverse protoporphyrin accumulation in the liver. Bone marrow transplantation may be an option for EPP patients who are at risk of developing hepatic complications.


Asunto(s)
Trasplante de Médula Ósea , Hígado/patología , Porfiria Eritropoyética/terapia , Animales , Femenino , Hígado/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Porfiria Eritropoyética/metabolismo , Porfiria Eritropoyética/patología , Protoporfirinas/biosíntesis
14.
J Comp Physiol B ; 170(1): 21-6, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10707321

RESUMEN

A Crassostrea gigas digestive gland copy DNA (cDNA) library constructed in the lambda phage ZapII (Stratagene, La Jola, USA) was screened with an amylase heterologous proble. To get access to the complete cDNA, a polymerase chain reaction extension was conducted using DNA extracted from the phages. The complete cDNA sequence is 1688 base pairs (EMBL = Y08370). The deduced protein sequence is 519 aminoacids long with a 19 aminoacid signal peptide. Similarity with Pecten maximus amylase is 72%. A 3-day nutrition experiment with a cyclic algal food supply was carried out. Amylase enzyme activities and mRNAs were individually measured on five animals, nine times a day. Messenger RNAs were quantified by dot hybridization using the previously characterized cDNA as probe. Variation of amylase mRNA was observed, in relation with the level of activity of the enzyme. Coordinated changes in RNA and enzyme levels suggested a possible transcriptional regulation of amylase in C. gigas as in vertebrates.


Asunto(s)
Amilasas/metabolismo , Ostreidae/enzimología , ARN Mensajero/metabolismo , Secuencia de Aminoácidos , Amilasas/genética , Animales , Secuencia de Bases , Clonación Molecular , Ingestión de Alimentos , Regulación de la Expresión Génica , Datos de Secuencia Molecular , Ostreidae/genética , Análisis de Regresión , Alineación de Secuencia , Factores de Tiempo
15.
Gene ; 236(2): 221-30, 1999 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-10452942

RESUMEN

Nm23 is a gene family encoding different isoforms of the nucleotide diphosphate kinase (NDPK), an enzyme involved in the synthesis of nucleoside triphosphates. In the present study, the organization and expression of the nm23-M1 gene encoding the mouse NDPKA isoform are described. This gene is about 10kb long and composed of five exons. The organization and the exon-intron boundaries are strictly conserved as compared to the human and rat related genes. The gene promoter region did not exhibit any consensus TATA box, SP1 binding element or Inr sequence. By contrast, TCF-1/LEF-1 binding elements and Pit-1 consensus sequence were present. Northern blotting and in situ hybridization methods were carried out in adult and 18.5 days post-coitum (dpc) mouse embryo, respectively. They showed tissue-specific expression of nm23-M1 transcripts, despite housekeeping gene promoter features. The strongest signals were detected in the nervous system, sensory organs and embryonic thymus. In contrast nm23-M2 mRNA was shown to be more widely expressed.The relationship between nm23-M1 gene tissue-specific expression and the putative binding element of the promoter region is discussed.


Asunto(s)
Proteínas de Unión al GTP Monoméricas , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Animales , Mapeo Cromosómico , Exones , Biblioteca Genómica , Hibridación in Situ , Mucosa Intestinal/embriología , Ratones , Ratones Endogámicos C57BL , Modelos Genéticos , Nucleósido Difosfato Quinasas NM23 , Nucleósido-Difosfato Quinasa/genética , Reacción en Cadena de la Polimerasa , Regiones Promotoras Genéticas , Homología de Secuencia de Aminoácido , Timo/embriología , Distribución Tisular , Factores de Transcripción/análisis , Transcripción Genética
16.
Brain Res Mol Brain Res ; 63(2): 351-65, 1999 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-9878823

RESUMEN

Nm23 has been identified as a gene family encoding different isoforms of the nucleoside diphosphate kinase. This protein is a key enzyme in the control of cellular concentrations of nucleoside triphosphates. Moreover, it has been shown to play important roles in various cellular functions such as differentiation and metastasis. In the present study, a second cDNA for nucleoside diphosphate kinase A (Nm23-M1) was isolated from a cDNA library of mouse embryonic stem cells. This clone encodes the same putative 152 aminoacids long protein as an already published cDNA but is longer in both its 5' and 3' untranslated regions. Tissue and cellular distribution of nm23-M1 mRNA was investigated by using Northern blot analysis and in situ hybridization. Nm23-M1 transcripts were found to be widely distributed throughout the mouse central nervous system with prominent expression in several restricted areas. No differences were noticed between the distribution of long and short transcripts. Furthermore, a similar pattern of expression was described in the central nervous system for nm23-M2 mRNA, encoding a second isoform of the nucleoside diphosphate kinase. However, the transcript of this isoform displayed a wider distribution and was expressed in all organs analysed by northern blotting. The possible involvement of nm23-M1 in differentiation of mouse nervous system is further discussed.


Asunto(s)
Sistema Nervioso Central/metabolismo , ADN Complementario/genética , Proteínas de Unión al GTP Monoméricas , Proteínas del Tejido Nervioso/genética , Nucleósido-Difosfato Quinasa/genética , Isoformas de Proteínas/genética , Factores de Transcripción/genética , Animales , Secuencia de Bases , Northern Blotting , Células Cultivadas , Clonación Molecular , Hibridación in Situ , Masculino , Ratones , Ratones Endogámicos C57BL , Datos de Secuencia Molecular , Familia de Multigenes , Nucleósido Difosfato Quinasas NM23
17.
Mol Mar Biol Biotechnol ; 6(3): 228-37, 1997 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9284561

RESUMEN

The digestive enzyme alpha-amylase in Pecten maximus has been purified from the digestive gland, where it is present as two isoforms, In order to gain information on its structure and regulation, a digestive gland cDNA library, constructed in lambda phage Zap II (Stratagene, La Jolla, Calif., U.S.A.), was screened with a shrimp alpha-amylase cDNA probe. Only 0.02% of the clones were positive, and the longest clone, having a size of 1700 bp and identical to that of the mRNA, was fully sequenced. It contains the complete cDNA coding frame for one of the amylase isoforms of P. maximus. The deduced protein sequence is 508 amino acids long, with a putative 18 amino acid, highly hydrophobic signal peptide and a mature enzyme of 489 residues. The molecular weight corresponds to 54,500 Da and the calculated isoelectric point is 6.76. Locations of conserved sequences confirms the high level of similarity with the other members of the family.


Asunto(s)
Regulación Enzimológica de la Expresión Génica/fisiología , Moluscos/enzimología , alfa-Amilasas/genética , alfa-Amilasas/aislamiento & purificación , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Cromatografía de Afinidad/métodos , Clonación Molecular , ADN Complementario/genética , Sistema Digestivo/enzimología , Datos de Secuencia Molecular , Peso Molecular , Moluscos/genética , ARN Mensajero/análisis , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Almidón , Ultrafiltración , alfa-Amilasas/química , alfa-Amilasas/metabolismo
19.
Fertil Steril ; 62(3): 648-50, 1994 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8062966

RESUMEN

In the light of the newly discovered implications of human interleukin for DA cells and leukemia inhibitory factor in embryology, we searched for the presence of this soluble cytokine in the supernatant of Vero cell coculture systems. Using a bioassay as well as a specific ELISA, we demonstrated that Vero cells are able to release large quantities of human interleukin for DA cells and leukemia inhibitory factor in the embryo-growing medium of such cocultures.


Asunto(s)
Inhibidores de Crecimiento/metabolismo , Interleucina-6 , Linfocinas/metabolismo , Células Vero/metabolismo , Animales , Bioensayo , Células Cultivadas , Chlorocebus aethiops , Medios de Cultivo/metabolismo , Técnicas Citológicas , Embrión de Mamíferos/citología , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Factor Inhibidor de Leucemia , Masculino , Ratones
20.
Artículo en Inglés | MEDLINE | ID: mdl-1677856

RESUMEN

1. O. edulis and C. gigas both exhibit a seasonal variation in AEC with minimum values in summer. Two factors, food and temperature, were examined to explain these low summer values. 2. The AEC level varied with food level but a seasonal pattern was still observed. Two age groups of oysters were tested, giving a similar response. 3. The effect of temperature on the seasonal variations in AEC was confirmed by a significant correlation between AEC and temperature. This relationship allows us to calculate an AEC standard that only retains the trophic information. 4. Different trophic levels were identified in Marennes-Oléron Bay with AEC standard but growth rate was not related to them. So, AEC may inform on the carrying capacity of a given area but does not predict growth performances which will depend on other parameters.


Asunto(s)
Adenosina Monofosfato/metabolismo , Crianza de Animales Domésticos , Metabolismo Energético/fisiología , Ostreidae/metabolismo , Estaciones del Año , Animales , Dieta , Nucleótidos/metabolismo , Temperatura
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