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1.
Anim Cogn ; 27(1): 42, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38833197

RESUMO

Cognitive bias is defined as the influence of emotions on cognitive processes. The concept of the cognitive judgement bias has its origins in human psychology but has been applied to animals over the past 2 decades. In this study we were interested in determining if laterality and personality traits, which are known to influence learning style, might also be correlated with a cognitive bias in the three-spined sticklebacks (Gasterosteus aculeatus). We used the judgement bias test with the go/no-go procedure where fish were first trained to discriminate between a black and white card and, after reaching a minimum learning criterion, tested their response to an ambiguous card (grey). Optimistic subjects were expected to have a high expectation of reward associated with an ambiguous stimulus, whereas pessimistic subjects a high expectation of non-reward. We used an emergence and a mirror test to quantify boldness and laterality, respectively. We hypothesised that male, bolder and more strongly lateralized fish would be more optimistic than female, shy and less strongly lateralised fish. We found that males and more strongly lateralized fish were more optimistic than females and less strongly lateralized fish. In addition, bold males were more optimistic than shy males as we predicted, but females showed the opposite pattern. Finally, fish trained on the black colour card learned the training task faster than those trained on a white card. Our results indicate that both laterality and personality traits are linked to animals' internal states (pessimistic or optimistic outlooks) which likely has broad implications for understanding animal behaviour particularly in a welfare context.


Assuntos
Lateralidade Funcional , Smegmamorpha , Animais , Masculino , Feminino , Smegmamorpha/fisiologia , Personalidade , Pessimismo , Julgamento , Otimismo , Recompensa , Cognição
2.
Nature ; 603(7901): 497-502, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35236989

RESUMO

Discrimination of self from non-self is fundamental to a wide range of immunological processes1. During pregnancy, the mother does not recognize the placenta as immunologically foreign because antigens expressed by trophoblasts, the placental cells that interface with the maternal immune system, do not activate maternal T cells2. Currently, these activation defects are thought to reflect suppression by regulatory T cells3. By contrast, mechanisms of B cell tolerance to trophoblast antigens have not been identified. Here we provide evidence that glycan-mediated B cell suppression has a key role in establishing fetomaternal tolerance in mice. B cells specific for a model trophoblast antigen are strongly suppressed through CD22-LYN inhibitory signalling, which in turn implicates the sialylated glycans of the antigen as key suppressive determinants. Moreover, B cells mediate the MHC-class-II-restricted presentation of antigens to CD4+ T cells, which leads to T cell suppression, and trophoblast-derived sialoglycoproteins are released into the maternal circulation during pregnancy in mice and humans. How protein glycosylation promotes non-immunogenic placental self-recognition may have relevance to immune-mediated pregnancy complications and to tumour immune evasion. We also anticipate that our findings will bolster efforts to harness glycan biology to control antigen-specific immune responses in autoimmune disease.


Assuntos
Antígenos , Placenta , Trofoblastos , Animais , Doenças Autoimunes , Linfócitos B , Feminino , Tolerância Imunológica , Camundongos , Placenta/imunologia , Polissacarídeos/metabolismo , Gravidez/imunologia
7.
Gene Ther ; 11(8): 711-21, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-14724672

RESUMO

Plasmid vectors have been widely used for DNA vaccines and gene therapy. Following intramuscular injection, the plasmid that persists is extrachromosomal and integration into host DNA, if it occurs at all, is negligible. However, new technologies for improving DNA delivery could increase the frequency of integration. In the present study, we tested the effect of electroporation on plasmid uptake and potential integration following intramuscular injection in mice, using a plasmid containing the mouse erythropoietin gene. Electroporation increased plasmid tissue levels by approximately six- to 34-fold. Using a quantitative gel-purification assay for integration, electroporation was found to markedly increase the level of plasmid associated with high-molecular-weight genomic DNA. To confirm integration and identify the insertion sites, we developed a new assay - referred to as repeat-anchored integration capture (RAIC) PCR - that is capable of detecting rare integration events in a complex mixture in vivo. Using this assay, we identified four independent integration events. Sequencing of the insertion sites suggested a random integration process, but with short segments of homology between the vector breakpoint and the insertion site in three of the four cases. This is the first definitive demonstration of integration of plasmid DNA into genomic DNA following injection in vivo.


Assuntos
DNA/metabolismo , Eritropoetina/genética , Terapia Genética/métodos , Genoma , Animais , DNA/administração & dosagem , Eletroporação , Injeções Intramusculares , Camundongos , Camundongos Endogâmicos BALB C , Reação em Cadeia da Polimerase/métodos , Transfecção/métodos
8.
G Ital Nefrol ; 20(2): 200-4, 2003.
Artigo em Italiano | MEDLINE | ID: mdl-12746806

RESUMO

Isolated peripheral arterial ischaemia (IPAI) is an unusual pathology of dialysis and peritoneal patients which represents the first sign of a complication of uraemia known as calciphylaxis. Recent studies have revealed an increased incidence of this complication. Risk factors are known but there is no consensus on them: elevated CaxP product, female gender, elevated serum parathormone. We present here the case of a 65-year-old man with 21-year history of dialysis, distal isolated ulceration and without any signs of severe vasculopathy. Our clinical diagnosis was calciphylaxis. In this case, the role of early PTX is not clear and the use of steroids is recommended only in non-ulcerating cases. The therapy gives good results but not in all patients. Electrical stimulation of the posterior roots of the spinal cord is an alternative approach to this case. We hypothesised that the electrical action, through cutaneous vasodilatation of afferent dorsal fibres and release of calcitonin gene-releasing protein, determines the release of prostaglandin E sub 2 that may positively affect the proliferation and activity of epidermal fibroblasts.


Assuntos
Calciofilaxia/etiologia , Terapia por Estimulação Elétrica , Isquemia/etiologia , Doenças Vasculares Periféricas/etiologia , Diálise Renal/efeitos adversos , Vias Aferentes/fisiopatologia , Idoso , Anti-Inflamatórios/uso terapêutico , Calciofilaxia/terapia , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Terapia Combinada , Dexametasona/uso terapêutico , Dinoprostona/metabolismo , Fibroblastos/patologia , Úlcera do Pé/tratamento farmacológico , Úlcera do Pé/etiologia , Úlcera do Pé/terapia , Humanos , Isquemia/terapia , Perna (Membro)/irrigação sanguínea , Plexo Lombossacral , Masculino , Modelos Neurológicos , Doenças Vasculares Periféricas/terapia , Temperatura Cutânea , Raízes Nervosas Espinhais , Vasodilatação
9.
Nephron ; 92(2): 487-9, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12218339

RESUMO

The present study was designed to test the biocompatibility of a new vitamin E-modified multilayer membrane compared with highly biocompatible polysulphone dialyzer and acrylonitrile dialyzer. Thirty patients (mean age 53.2 +/- 15.3 SD years; dialytic age 36 +/- 5.6 months) were selected for the study. The study was divided into three periods of 6 months (phases A, B and C). In the first phase (from Jan. 1999 to June 1999) patients undergoing maintenance bicarbonate dialysis were randomly divided into three filter groups composed, respectively, of 10 patients: acrylonitrile group, polysulphone group and vitamin E-coated dialyzer group. In the phase B (from July 1999 to Dec. 1999) and in the phase C (from Jan. 2000 to June 2000), all three groups changed their own dialysis membranes. Vitamin E-coated dialyzer causes significant decreases in beta(2)-microglobulin, ferritin and immunoglobulin G, a normalization of complement C3 and an increase of plasmatic vitamin E compared to other filters. In the VE group homocysteine decreases but not in a significant manner. In addition, this dialyzer seems not to influence lipid pattern and protein-energy malnutrition parameters. These results clearly show a positive effect of this new filter in influencing different biochemical parameters, perhaps saving vitamin E and reducing polymorphonuclear cell activation.


Assuntos
Rins Artificiais , Vitamina E/administração & dosagem , Vitamina E/sangue , Acrilonitrila , Adulto , Idoso , Materiais Biocompatíveis , Estudos Cross-Over , Feminino , Sequestradores de Radicais Livres/administração & dosagem , Humanos , Masculino , Teste de Materiais , Membranas Artificiais , Pessoa de Meia-Idade , Polímeros , Diálise Renal , Sulfonas
10.
Tissue Antigens ; 59(4): 325-7, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12135434

RESUMO

This paper describes 10 novel HLA-A alleles that have been characterized by DNA sequencing. Seven alleles, A*0308, A*2616, A*3009, A*3206, A*3403, A*3602 and A*6604 carry motifs observed in other HLA-A alleles, suggesting that gene conversion has created this diversity. The remaining three alleles, A*01012, A*0306 and A*2617, contain polymorphisms not previously found in any "classical" class I allele. All alleles were identified due to unexpected probe hybridization patterns during routine SSOP typing. Exons 2 and 3 of each allele were subsequently characterized by DNA sequencing.


Assuntos
Alelos , Antígenos HLA-A/genética , Humanos , Polimorfismo Genético
11.
Tissue Antigens ; 57(5): 474-7, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11556974

RESUMO

Twelve new B*15 alleles are described. All of the known B*15 alleles are divided into subgroups based on serologic assignments and/or nucleotide sequence polymorphisms. These groups might be used as a reference for DNA-based testing at an intermediate (i.e. "serologic") level of resolution.


Assuntos
Alelos , Antígenos HLA-B/genética , Motivos de Aminoácidos , Sequência de Aminoácidos , Éxons/imunologia , Conversão Gênica/imunologia , Antígenos HLA-B/química , Antígeno HLA-B15 , Humanos , Dados de Sequência Molecular , Família Multigênica/imunologia
12.
Tissue Antigens ; 57(5): 481-5, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11556976

RESUMO

This paper describes 29 novel HLA-B locus alleles identified during low-resolution typing. The majority of the novel alleles carry new patterns of previously known polymorphic motifs or codons. Three alleles carry alterations in the Bw4/Bw6 epitope. Five alleles carry novel substitutions.


Assuntos
Alelos , Antígenos HLA-B/genética , Família Multigênica/imunologia , Reações Cruzadas/genética , Antígenos HLA-B/imunologia , Humanos , Dados de Sequência Molecular
13.
Tissue Antigens ; 57(5): 486-8, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11556977

RESUMO

This paper describes 9 novel HLA-B locus alleles. All of the alleles carry sequence motifs observed in other HLA-B alleles.


Assuntos
Alelos , Antígenos HLA-B/genética , Família Multigênica/imunologia , Antígenos HLA-B/imunologia , Humanos , Dados de Sequência Molecular
14.
Tissue Antigens ; 57(4): 373-5, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11380951

RESUMO

This paper describes 13 novel HLA-B locus alleles, B*0809, B*0812, B*0813, B*0814, B*14062, B*3804, B*3806, B*3914, B*3915, B*3918, B*3919, B*3920, and B*3922 which represent new patterns of known polymorphic residues.


Assuntos
Alelos , Antígenos HLA-B/genética , Proteínas Repressoras/genética , Antígeno HLA-B14 , Antígeno HLA-B18 , Antígeno HLA-B38 , Antígeno HLA-B39 , Humanos
15.
Mol Cell Biol ; 21(5): 1621-32, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11238899

RESUMO

We generated mice carrying a STAT3 allele amenable to Cre-mediated deletion and intercrossed them with Mx-Cre transgenic mice, in which the expression of Cre recombinase can be induced by type I interferon. Interferon-induced deletion of STAT3 occurred very efficiently (more than 90%) in the liver and slightly less efficiently (about 70%) in the bone marrow. Analysis of the induction of liver acute-phase genes in response to bacterial lipopolysaccharide unequivocally identifies STAT3 as a fundamental mediator of their induction. The different degrees of defectiveness displayed by the various genes allowed us to differentiate them into three separate groups according to their degree of dependence on STAT3. Induction was totally defective for group I genes, defective at 24 h but almost normal at earlier time points for group II genes, and only slightly defective for group III genes. This division was in good agreement with the known structures of the respective promoters. We also found that the overall induction of the transcription factors C/EBP beta and -delta was only minimally defective in the absence of STAT3. Finally, even though corticosterone levels and action were found to be normal in the conditional-mutant mice, production of both proinflammatory and antiinflammatory cytokines was increased and prolonged, probably as a result of STAT3 deletion in macrophages.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Regulação da Expressão Gênica , Fígado/metabolismo , Transativadores/fisiologia , Fatores de Transcrição , Proteínas Virais , Alelos , Animais , Sequência de Bases , Western Blotting , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Proteína delta de Ligação ao Facilitador CCAAT , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Diferenciação Celular , Núcleo Celular/metabolismo , Corticosterona/metabolismo , Cruzamentos Genéticos , Citocinas/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Dexametasona/farmacologia , Ensaio de Imunoadsorção Enzimática , Feminino , Deleção de Genes , Genótipo , Glucocorticoides/farmacologia , Humanos , Integrases/metabolismo , Interferon Tipo I/metabolismo , Lipopolissacarídeos/farmacologia , Sistema de Sinalização das MAP Quinases , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Modelos Genéticos , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Ratos , Fator de Transcrição STAT3 , Fatores de Tempo , Transativadores/genética , Transativadores/metabolismo
16.
Hum Gene Ther ; 11(13): 1891-900, 2000 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-10986561

RESUMO

We have investigated the efficacy of a gene transfer strategy based on plasmid DNA electroinjection for the correction of anemia associated with renal failure. An expression plasmid encoding the rat erythropoietin (EPO) cDNA under the control of the CMV promoter as constructed and utilized for this work. Electroinjection of pCMV/rEPO in different rat muscles yielded sustained and long-term EPO production and secretion. The muscle-produced EPO corrected the anemia in five of six nephrectomized rats, used as a model of renal failure. The efficiency of muscle transduction was comparable in rats and mice injected with equivalent amounts of DNA per kilogram of body weight. These results demonstrate that gene electrotransfer can be applied to produce therapeutically significant levels of erythropoietin in chronic renal failure.


Assuntos
Anemia/terapia , Eritropoetina/genética , Técnicas de Transferência de Genes , Falência Renal Crônica/complicações , Músculo Esquelético/fisiologia , Anemia/etiologia , Animais , Citomegalovirus/genética , Modelos Animais de Doenças , Eritropoetina/metabolismo , Eritropoetina/farmacologia , Terapia Genética/métodos , Hematócrito , Injeções/métodos , Camundongos , Camundongos Endogâmicos BALB C , Nefrectomia , Plasmídeos/farmacologia , Regiões Promotoras Genéticas , Coelhos , Ratos , Ratos Sprague-Dawley , Transdução Genética
17.
Hum Immunol ; 61(8): 808-15, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10980391

RESUMO

The frequency of each B*40 allele was determined by DNA sequencing in four major United States populations: Caucasians, African Americans, Asians/Pacific Islanders, and Hispanics. Thirty-two individuals from each ethnic group, who were previously described serologically as B40, B60, or B61, were randomly selected out of a pool of 82,979 unrelated individuals for allele characterization. Out of nine different B*40 alleles identified in this study, B*4001 and B*4002 were the two most frequent B*40 alleles in all the population groups. B*4001 was the primary B*40 allele seen in Caucasians (83%) and African Americans (76%), while B*4002 was found in the majority of Hispanics (62%). The distributions of both alleles were comparable in the Asian/Pacific Islander population. These two alleles were the only B*40 alleles detected in Caucasians while four to five additional B*40 alleles were seen in the other population groups. The other B*40 alleles detected in this study included: B*4003 and B*4010 in Asian/Pacific Islanders; B*4012 and B*4016 in African Americans; and B*4004, B*4006, and B*4027 in Hispanics. Analysis revealed significant differences between Hispanics and all other groups as well as between African Americans and Asian/Pacific Islanders. This report also describes five novel B*40 alleles: B*4019, B*4020, B*4024, B*4027, and B*4028.


Assuntos
Alelos , Variação Genética , Antígenos HLA-B/genética , Frequência do Gene , Antígenos HLA-B/classificação , Antígeno HLA-B40 , Estados Unidos
18.
Proc Natl Acad Sci U S A ; 96(11): 6417-22, 1999 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-10339602

RESUMO

We show that an electric treatment in the form of high-frequency, low-voltage electric pulses can increase more than 100-fold the production and secretion of a recombinant protein from mouse skeletal muscle. Therapeutical erythopoietin (EPO) levels were achieved in mice with a single injection of as little as 1 microgram of plasmid DNA, and the increase in hematocrit after EPO production was stable and long-lasting. Pharmacological regulation through a tetracycline-inducible promoter allowed regulation of serum EPO and hematocrit levels. Tissue damage after stimulation was transient. The method described thus provides a potentially safe and low-cost treatment for serum protein deficiencies.


Assuntos
Eritropoetina/genética , Técnicas de Transferência de Genes , Músculo Esquelético/fisiologia , Regiões 5' não Traduzidas/genética , Animais , Citomegalovirus/genética , Estimulação Elétrica , Eletroporação/métodos , Eritropoetina/biossíntese , Eritropoetina/sangue , Feminino , Regulação da Expressão Gênica , Cinética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Músculo Esquelético/citologia , Plasmídeos , Regiões Promotoras Genéticas , Proteínas Recombinantes/biossíntese , Sensibilidade e Especificidade , Fatores de Tempo
19.
J Virol ; 73(3): 2517-26, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9971837

RESUMO

The adeno-associated virus (AAV) is unique in its ability to target viral DNA integration to a defined region of human chromosome 19 (AAVS1). Since AAVS1 sequences are not conserved in a rodent's genome, no animal model is currently available to study AAV-mediated site-specific integration. We describe here the generation of transgenic rats and mice that carry the AAVS1 3.5-kb DNA fragment. To test the response of the transgenic animals to Rep-mediated targeting, primary cultures of mouse fibroblasts, rat hepatocytes, and fibroblasts were infected with wild-type wt AAV. PCR amplification of the inverted terminal repeat (ITR)-AAVS1 junction revealed that the AAV genome integrated into the AAVS1 site in fibroblasts and hepatocytes. Integration in rat fibroblasts was also observed upon transfection of a plasmid containing the rep gene under the control of the p5 and p19 promoters and a dicistronic cassette carrying the green fluorescent protein (GFP) and neomycin (neo) resistance gene between the ITRs of AAV. The localization of the GFP-Neo sequence in the AAVS1 region was determined by Southern blot and FISH analysis. Lastly, AAV genomic DNA integration into the AAVS1 site in vivo was assessed by virus injection into the quadriceps muscle of transgenic rats and mice. Rep-mediated targeting to the AAVS1 site was detected in several injected animals. These results indicate that the transgenic lines are proficient for Rep-mediated targeting. These animals should allow further characterization of the molecular aspects of site-specific integration and testing of the efficacy of targeted integration of AAV recombinant vectors designed for human gene therapy.


Assuntos
Dependovirus/genética , Integração Viral , Animais , Animais Geneticamente Modificados , Células Cultivadas , Terapia Genética , Genoma Viral , Masculino , Camundongos , Ratos , Ratos Sprague-Dawley
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