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1.
Head Neck ; 40(4): 846-854, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29155470

RESUMO

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.


Assuntos
Doenças das Artérias Carótidas/terapia , Embolização Terapêutica/métodos , Procedimentos Endovasculares/métodos , Neoplasias de Cabeça e Pescoço/cirurgia , Esvaziamento Cervical/efeitos adversos , Stents , Doença Aguda , Adulto , Idoso , Doenças das Artérias Carótidas/etiologia , Artéria Carótida Primitiva/fisiopatologia , Artéria Carótida Interna/fisiopatologia , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Esvaziamento Cervical/métodos , Estudos Observacionais como Assunto , Medição de Risco , Ruptura Espontânea/etiologia , Ruptura Espontânea/terapia , Síndrome , Resultado do Tratamento
2.
Comp Biochem Physiol B Biochem Mol Biol ; 163(1): 96-100, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22580267

RESUMO

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.


Assuntos
Amilases/genética , Amilases/metabolismo , Crassostrea/enzimologia , Amido/farmacologia , Animais , Crassostrea/efeitos dos fármacos , Crassostrea/genética , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/genética , RNA Mensageiro/genética
3.
Anim Genet ; 39(6): 662-5, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18717666

RESUMO

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.


Assuntos
Amilases/genética , Comportamento Alimentar , Ostreidae/genética , Polimorfismo Genético , Amilases/metabolismo , Animais , Sequência de Bases , Primers do DNA , Cinética , Ostreidae/enzimologia , Ostreidae/fisiologia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição
4.
Anim Genet ; 37(4): 348-51, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16879344

RESUMO

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.


Assuntos
Crassostrea/crescimento & desenvolvimento , Crassostrea/genética , Polimorfismo Genético , alfa-Amilases/genética , Animais , Cruzamento , França , Marcadores Genéticos , Genótipo
5.
Genomics ; 87(1): 84-92, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16314073

RESUMO

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.


Assuntos
Substituição de Aminoácidos , Mutação de Sentido Incorreto , Porfiria Eritropoética/enzimologia , Uroporfirinogênio III Sintetase/genética , Animais , Transplante de Medula Óssea , Modelos Animais de Doenças , Terapia Genética , Camundongos , Camundongos Transgênicos , Porfiria Eritropoética/patologia , Porfiria Eritropoética/terapia , Uroporfirinogênio III Sintetase/metabolismo , Uroporfirinas/metabolismo
6.
Comp Biochem Physiol B Biochem Mol Biol ; 140(4): 635-46, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15763519

RESUMO

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.


Assuntos
Regulação Enzimológica da Expressão Gênica , Glicogênio Fosforilase/genética , Glicogênio Sintase/genética , Ostreidae/enzimologia , Sequência de Aminoácidos , Animais , Clonagem Molecular , DNA Complementar/genética , DNA Complementar/isolamento & purificação , Glicogênio Fosforilase/isolamento & purificação , Glicogênio Sintase/isolamento & purificação , Dados de Sequência Molecular , Filogenia , Estações do Ano , Alinhamento de Sequência , Distribuição Tecidual
7.
Biochem Biophys Res Commun ; 320(2): 592-8, 2004 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-15219870

RESUMO

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.


Assuntos
Biomarcadores , Genes , Células Germinativas , Ostreidae/embriologia , Animais , Sequência de Bases , Primers do DNA , Feminino , Hibridização In Situ/métodos , Masculino , Ostreidae/genética , Reação em Cadeia da Polimerase/métodos , RNA Mensageiro/genética
8.
Placenta ; 25(1): 20-8, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15013635

RESUMO

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.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento/genética , Núcleosídeo-Difosfato Quinase/genética , Trofoblastos/enzimologia , Desenvolvimento Embrionário e Fetal/fisiologia , Proteínas do Olho/metabolismo , Feminino , Idade Gestacional , Humanos , Imuno-Histoquímica , Hibridização In Situ , Antígeno Ki-67/análise , Nucleosídeo NM23 Difosfato Quinases , Proteínas do Tecido Nervoso/metabolismo , Núcleosídeo-Difosfato Quinase/metabolismo , Gravidez
9.
J Bioenerg Biomembr ; 35(1): 19-30, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12848338

RESUMO

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.


Assuntos
Mama/metabolismo , Retardo do Crescimento Fetal/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Regulação Enzimológica da Expressão Gênica/genética , Modelos Animais , Núcleosídeo-Difosfato Quinase , Proteínas/genética , Proteínas/metabolismo , Animais , Animais Recém-Nascidos , Clonagem Molecular , Feminino , Retardo do Crescimento Fetal/metabolismo , Camundongos , Camundongos Knockout/embriologia , Camundongos Knockout/crescimento & desenvolvimento , Camundongos Knockout/metabolismo , Nucleosídeo NM23 Difosfato Quinases , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transdução de Sinais/genética , Relação Estrutura-Atividade
10.
Mar Biotechnol (NY) ; 5(4): 360-72, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14719164

RESUMO

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.


Assuntos
Alelos , Amilases/genética , Genética Populacional , Ostreidae/genética , Polimorfismo Genético , Animais , Sequência de Bases , Mapeamento Cromossômico , Primers do DNA , DNA Complementar/genética , França , Perfilação da Expressão Gênica , Frequência do Gene , Dados de Sequência Molecular , Polimorfismo de Fragmento de Restrição , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA
11.
Gene ; 296(1-2): 87-97, 2002 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-12383506

RESUMO

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.


Assuntos
Proteínas Monoméricas de Ligação ao GTP/genética , Núcleosídeo-Difosfato Quinase/genética , Fatores de Transcrição/genética , Sequência de Aminoácidos , Animais , Northern Blotting , Clonagem Molecular , DNA/química , DNA/genética , DNA Complementar/química , DNA Complementar/genética , Embrião de Mamíferos/enzimologia , Embrião de Mamíferos/metabolismo , Éxons , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Genes/genética , Humanos , Hibridização In Situ , Íntrons , Isoenzimas/genética , Camundongos , Dados de Sequência Molecular , Nucleosídeo NM23 Difosfato Quinases , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Sítio de Iniciação de Transcrição
12.
Br J Cancer ; 86(1): 117-22, 2002 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-11857022

RESUMO

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.


Assuntos
Galanina/análise , Neuroblastoma/química , Receptores de Neuropeptídeos/análise , Diferenciação Celular , Criança , Pré-Escolar , Feminino , Galanina/metabolismo , Humanos , Imuno-Histoquímica , Lactente , Masculino , Neuroblastoma/patologia , Receptores de Galanina
13.
Hepatology ; 32(1): 73-81, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10869291

RESUMO

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.


Assuntos
Transplante de Medula Óssea , Fígado/patologia , Porfiria Eritropoética/terapia , Animais , Feminino , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Porfiria Eritropoética/metabolismo , Porfiria Eritropoética/patologia , Protoporfirinas/biossíntese
14.
J Comp Physiol B ; 170(1): 21-6, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10707321

RESUMO

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.


Assuntos
Amilases/metabolismo , Ostreidae/enzimologia , RNA Mensageiro/metabolismo , Sequência de Aminoácidos , Amilases/genética , Animais , Sequência de Bases , Clonagem Molecular , Ingestão de Alimentos , Regulação da Expressão Gênica , Dados de Sequência Molecular , Ostreidae/genética , Análise de Regressão , Alinhamento de Sequência , Fatores de Tempo
15.
Gene ; 236(2): 221-30, 1999 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-10452942

RESUMO

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.


Assuntos
Proteínas Monoméricas de Ligação ao GTP , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Animais , Mapeamento Cromossômico , Éxons , Biblioteca Genômica , Hibridização In Situ , Mucosa Intestinal/embriologia , Camundongos , Camundongos Endogâmicos C57BL , Modelos Genéticos , Nucleosídeo NM23 Difosfato Quinases , Núcleosídeo-Difosfato Quinase/genética , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas , Homologia de Sequência de Aminoácidos , Timo/embriologia , Distribuição Tecidual , Fatores de Transcrição/análise , Transcrição Gênica
16.
Brain Res Mol Brain Res ; 63(2): 351-65, 1999 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-9878823

RESUMO

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.


Assuntos
Sistema Nervoso Central/metabolismo , DNA Complementar/genética , Proteínas Monoméricas de Ligação ao GTP , Proteínas do Tecido Nervoso/genética , Núcleosídeo-Difosfato Quinase/genética , Isoformas de Proteínas/genética , Fatores de Transcrição/genética , Animais , Sequência de Bases , Northern Blotting , Células Cultivadas , Clonagem Molecular , Hibridização In Situ , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Família Multigênica , Nucleosídeo NM23 Difosfato Quinases
17.
Mol Mar Biol Biotechnol ; 6(3): 228-37, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9284561

RESUMO

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.


Assuntos
Regulação Enzimológica da Expressão Gênica/fisiologia , Moluscos/enzimologia , alfa-Amilases/genética , alfa-Amilases/isolamento & purificação , Sequência de Aminoácidos , Animais , Sequência de Bases , Cromatografia de Afinidade/métodos , Clonagem Molecular , DNA Complementar/genética , Sistema Digestório/enzimologia , Dados de Sequência Molecular , Peso Molecular , Moluscos/genética , RNA Mensageiro/análise , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Amido , Ultrafiltração , alfa-Amilases/química , alfa-Amilases/metabolismo
19.
Fertil Steril ; 62(3): 648-50, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8062966

RESUMO

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.


Assuntos
Inibidores do Crescimento/metabolismo , Interleucina-6 , Linfocinas/metabolismo , Células Vero/metabolismo , Animais , Bioensaio , Células Cultivadas , Chlorocebus aethiops , Meios de Cultura/metabolismo , Técnicas Citológicas , Embrião de Mamíferos/citologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Fator Inibidor de Leucemia , Masculino , Camundongos
20.
Artigo em Inglês | MEDLINE | ID: mdl-1677856

RESUMO

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.


Assuntos
Monofosfato de Adenosina/metabolismo , Criação de Animais Domésticos , Metabolismo Energético/fisiologia , Ostreidae/metabolismo , Estações do Ano , Animais , Dieta , Nucleotídeos/metabolismo , Temperatura
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