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1.
Reprod Domest Anim ; 45(6): e387-91, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20210879

RESUMO

Early bovine embryos are vulnerable to heat stress during the first few days after fertilization. The inhibitory effect of heat stress on embryonic development is known to be associated with oxidative stress, which can be attenuated by antioxidants. In the present study, we focused on the use of astaxanthin as an antioxidant and examined the effects of astaxanthin-containing oil (Ax) on post-fertilization development of bovine embryos subjected to heat stress in vitro and the expression of stress-related genes. Bovine 1-cell embryos were in vitro produced by in vitro maturation and fertilization (IVF) of oocytes recovered from abattoir-derived ovaries. At 20 h post-insemination (hpi, 0 h = the start of IVF), the embryos were introduced in modified synthetic oviduct fluid supplemented with 25 ppm of Ax (concentration of astaxanthin was 0.25 ppm) or vehicle (dimethyl sulfoxide) up to 72 hpi. The embryos were basically cultured at 38.5°C, and in the heat stress group, embryos were exposed twice to 40.5°C for 10 h (at 20-30 and 44-54 hpi). Under the condition without the Ax treatment, the cleavage rate, rate of development to the 5-8 cell stage, blastocyst yield from cultured embryos and that from cleaved embryos were lower in the heat stress group than in the group not subjected to heat stress (p < 0.05). In the heat stress group, the rate of development to the 5-8 cell stage was improved (p < 0.05) by the addition of Ax. Subsequently, we performed semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) to investigate the effects of heat stress and Ax on the mRNA expression of Src homology 2 domain-containing transforming protein C1 (SHC1), an oxidative stress adaptor protein, and superoxide dismutase 2 (SOD2), a mitochondrial reactive oxygen species (ROS) scavenger. In 5-8 cell embryos at 72 hpi, the mRNA expression levels of SHC1 and SOD2 were lower in the Ax- and heat-treated group than in the other groups (p < 0.05). These results suggest that Ax added to the culture medium ameliorates the embryonic development impaired by heat stress with its altering effects on the expression of stress-related genes.


Assuntos
Bovinos/embriologia , Desenvolvimento Embrionário/efeitos dos fármacos , Temperatura Alta , Estresse Fisiológico , Animais , Fertilização in vitro/veterinária , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Óleos/química , Xantofilas/química , Xantofilas/farmacologia
2.
J Immunol ; 165(2): 1138-45, 2000 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-10878393

RESUMO

Expansion of CD4+CD28null T cells is a characteristic finding in patients with rheumatoid arthritis. Despite lacking CD28 molecules, these unusual CD4 T cells undergo clonal proliferation and form large and long-lived clonal populations. They produce high levels of IFN-gamma, exhibit autoreactivity, and have cytolytic function. The mechanisms facilitating the expansion and longevity of CD4+CD28null T cell clones in vivo are unknown. Here, we report that CD4+CD28null, but not CD4+CD28+, T cells express MHC class I-recognizing receptors normally found on NK cells. CD4+CD28null T cells preferentially expressed killer cell activating receptors (KAR), often in the absence of killer cell inhibitory receptors. Cross-linking of KAR molecules enhanced the proliferative response to TCR-mediated stimulation, but not the cytolytic function of CD4+CD28null T cells, suggesting different signaling pathways in CD4 T cells and NK cells. Triggering of KAR signaling led to the phosphorylation of several cellular targets, although the pattern of phosphorylation differed from that induced by the TCR. Aberrant expression of KAR molecules in the absence of inhibitory receptors and in the appropriate HLA setting may lead to the clonal outgrowth of autoreactive CD4+CD28null T cells commonly seen in rheumatoid arthritis.


Assuntos
Artrite Reumatoide/imunologia , Antígenos CD28 , Linfócitos T CD4-Positivos/metabolismo , Células Matadoras Naturais/metabolismo , Ativação Linfocitária , Receptores Imunológicos/fisiologia , Subpopulações de Linfócitos T/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Adjuvantes Imunológicos/fisiologia , Artrite Reumatoide/metabolismo , Artrite Reumatoide/patologia , Antígenos CD28/biossíntese , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Divisão Celular/imunologia , Células Clonais , Citotoxicidade Imunológica , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Células Matadoras Naturais/imunologia , Proteínas de Membrana , Fosforilação , Fosfotirosina/metabolismo , Receptores Imunológicos/biossíntese , Receptores Imunológicos/metabolismo , Receptores KIR , Receptores de Células Matadoras Naturais , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/patologia
3.
Steroids ; 64(12): 805-11, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10576214

RESUMO

A method is described for the preparation of multi-labeled tetrahydrocortisol (3alpha,11beta,17alpha,21-tetrahydroxy-5beta-[1, 2,3,4,5-2H5]pregnan-20-one, THF-d5), allo-tetrahydrocortisol (3alpha,11beta,17alpha,21-tetrahydroxy-5alpha-[1 ,2,3,4,5-2H5]pregnan-20-one, allo-THF-d5), and tetrahydrocortisone (3alpha,17alpha,21-trihydroxy-5beta-[1,2,3,4,5-2H5]pre gnane-11,20-dione, THE-d5) containing five non-exchangeable deuterium atoms in the steroid ring A. Reductive deuteration at C-1, C-2, C-3, C-4, and C-5 of prednisolone or prednisone was performed in CH3COOD with rhodium (5%) on alumina under the deuterium atmosphere. The isotopic purities of the labeled compounds as [2H5]-form were estimated to be 86.17 atom%D for THF-d5, 74.46 atom%D for allo-THF-d5 and 81.90 atom%D for THE-d5, based on the ion intensities in the region of the molecular ion of methoxime-trimethylsilyl (MO-TMS) derivatives measured by GC-MS.


Assuntos
Hidrocortisona/metabolismo , Tetra-Hidrocortisol/metabolismo , Tetra-Hidrocortisona/metabolismo , Cromatografia Líquida , Deutério , Humanos , Marcação por Isótopo , Espectroscopia de Ressonância Magnética , Espectrometria de Massas
4.
Arthritis Rheum ; 41(12): 2108-16, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9870867

RESUMO

OBJECTIVE: To identify the functional properties of CD4+ CD28- T cells, which accumulate and clonally expand in patients with rheumatoid arthritis (RA). METHODS: The gene expression of molecules involved in T cell effector functions was compared in CD4+ CD28- and CD4+ CD28+ T cell clones. The expression of differentially up-regulated genes was confirmed by flow cytometry of T cells and by 2-color immunohistochemistry of rheumatoid synovial tissue. Cytotoxicity of CD4+ CD28- T cells was tested by anti-CD3 redirected lysis of Fc receptor-positive target cells. RESULTS: CD4+ CD28- T cell clones lacked messenger RNA for the CD40 ligand (CD40L) but transcribed the perforin gene. Perforin was also found in freshly isolated CD4+ CD28- peripheral blood lymphocytes from RA patients. CD4+ CD28-, but not CD4+ CD28+, T cell clones lysed Fc receptor-bearing target cells. CD4+ perforin-positive T cells were present in the synovial tissue, where their frequency correlated with the expansion of the CD4+ CD28- compartment in the periphery. Among tissue-infiltrating CD4+ T cells, only the CD40L-negative subset expressed perforin transcripts. CONCLUSION: Clonally expanded CD4+ CD28- T cells are functionally specialized for killing, while they lack the ability to provide B cell help. Tissue-infiltrating CD4+ T cells can be subdivided phenotypically and functionally into at least 2 distinct subsets based on their expression of perforin and CD40L. Because the expansion of CD4+ CD28- T cells is associated with extraarticular RA, T cell-mediated cytotoxicity may be particularly important in these most severe complications of RA.


Assuntos
Artrite Reumatoide/imunologia , Artrite Reumatoide/patologia , Linfócitos T CD4-Positivos/fisiologia , Sinovite/imunologia , Sinovite/patologia , Subpopulações de Linfócitos T/fisiologia , Artrite Reumatoide/sangue , Antígenos CD28/sangue , Antígenos CD40/análise , Ligante de CD40 , Células Clonais/metabolismo , Granzimas , Humanos , Glicoproteínas de Membrana/análise , Glicoproteínas de Membrana/biossíntese , Glicoproteínas de Membrana/genética , Perforina , Proteínas Citotóxicas Formadoras de Poros , Serina Endopeptidases/biossíntese , Serina Endopeptidases/genética , Linfócitos T/imunologia , Linfócitos T/metabolismo , Linfócitos T Citotóxicos/fisiologia
5.
J Chromatogr B Biomed Sci Appl ; 706(2): 181-90, 1998 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-9551804

RESUMO

A capillary gas chromatographic-mass spectrometric method for the simultaneous determination of tetrahydrocortisol (THF, 3alpha,11beta,17alpha,21-tetrahydroxy-5beta-preg nane-20-one), allo-tetrahydrocortisol (allo-THF, 3alpha,11beta,17alpha,21-tetrahydroxy-5alpha-pre gnane-20-one) and tetrahydrocortisone (THE, 3alpha,17alpha,21-trihydroxy-5beta-pregnane-11,20-dion e) in human plasma and urine is described. [1,2,3,4,5-2H5]THF (THF-d5), allo-[1,2,3,4,5-2H5]THF (allo-THF-d5) and [1,2,3,4,5-2H5]THE (THE-d5) were used as internal standards. A double derivatization (bismethylenedioxypentafluoropropionate, BMD-PFP) made possible the separation of the three tetrahydrocorticoids with good gas chromatographic behavior. Quantitation was carried out by selected-ion monitoring of the characteristic fragment ions ([M-30]+) of the BMD-PFP derivatives of THF, allo-THF and THE. The sensitivity, specificity, precision and accuracy of the method were demonstrated to be satisfactory for measuring low concentrations of THF, allo-THF and THE in human plasma and urine.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Tetra-Hidrocortisol/análise , Tetra-Hidrocortisona/análise , Deutério , Humanos , Técnicas de Diluição do Indicador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tetra-Hidrocortisol/sangue , Tetra-Hidrocortisol/química , Tetra-Hidrocortisol/urina , Tetra-Hidrocortisona/sangue , Tetra-Hidrocortisona/química , Tetra-Hidrocortisona/urina
6.
J Immunol ; 158(2): 1020-5, 1997 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-8993025

RESUMO

Apoptosis is found in labial salivary glands of patients with Sjogren's syndrome (SS). To analyze the pathogenesis of apoptosis in labial salivary glands of SS patients, we examined the expression of Fas Ag and Fas ligand (FasL) and TCR on T cells susceptible to anti-Fas mAbs (CH-11). Fas Ag is expressed on epithelial cells and mononuclear cells in the salivary glands as observed by an immunohistochemical method. FasL is over-expressed specifically on T cells infiltrating into the labial salivary glands as seen by an reverse transcription-PCR method. These results suggest that apoptosis in SS lips is mediated by a Fas/FasL pathway. PCR single-strand conformation polymorphism (SSCP) clearly demonstrated that more than 40% of the T cells accumulated in labial salivary glands are deleted by incubation with CH-11 for 24 h in vitro, indicating that these expanded cells are Fas sensitive. junctional sequence analysis showed that the same conserved amino acid motifs (LAGG, RLA, SLG, QGPG, PGG, GGE, RGR, KPG, AGD, and MLG) in complementarity determining region 3 (CDR3) are found in Fas-sensitive T cell clones, whereas they are not detected in Fas-resistant clones, suggesting that Fas-sensitive T cells recognize restricted T cell epitopes on autoantigens. In conclusion, the findings suggest that Fas-sensitive T cells in labial salivary glands of SS patients are generated by Ag stimulation and might function as autoreactive T cells.


Assuntos
Lábio/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/análise , Glândulas Salivares Menores/citologia , Glândulas Salivares Menores/imunologia , Síndrome de Sjogren/imunologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Receptor fas/farmacologia , Sequência de Aminoácidos , Apoptose/efeitos dos fármacos , Proteína Ligante Fas , Humanos , Ligantes , Glicoproteínas de Membrana/farmacologia , Dados de Sequência Molecular
7.
Nihon Kyobu Shikkan Gakkai Zasshi ; 35(12): 1305-11, 1997 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-9567073

RESUMO

We evaluated 240 consecutive subjects (aged 20-91) without cardiopulmonary, endocrine or, neuromuscular disease consecutively regarding pulmonary function (TLC, VC, FEV1, RV) and static maximal inspiratory (PImax) and expiratory (PEmax) pressures. PImax and PEmax declined with advancing age. PImax correlated with grip strength, VC, FEV1, height, weight, and RV/TLC. PEmax also correlated with grip strength, TLC, VC, FEV1, height, and weight. Age, height, weight, and grip strength were entered stepwise into multiple linear regression models with PImax or PEmax as the dependent variable. Stepwise regression analysis revealed that grip strength was an independent predictor for both PImax and PEmax. However, age itself was not an independent predictor for PImax or PEmax. These results suggest that static maximal respiratory pressures decrease with aging, and that age-dependent changes in respiratory muscle function may depend on other factors, including lung volume, skeletal muscle status, and body composition.


Assuntos
Respiração/fisiologia , Músculos Respiratórios/fisiologia , Capacidade Pulmonar Total/fisiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Composição Corporal , Feminino , Força da Mão/fisiologia , Humanos , Complacência Pulmonar/fisiologia , Masculino , Pessoa de Meia-Idade , Pressão
9.
J Clin Invest ; 97(8): 1969-77, 1996 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-8621782

RESUMO

Sjogren's syndrome (SS) is an autoimmune disease characterized by lymphocytic infiltration into lacrimal and salivary glands leading to symptomatic dry eyes and mouth. Immunohistological studies have clarified that the majority of infiltrating lymphocytes around the lacrimal glands and labial salivary glands are CD4 positive alphabeta T cells. To analyze the pathogenesis of T cells infiltrating into lacrimal and labial salivary glands, we examined T cell clonotype of these cells in both glands from four SS patients using PCR-single-strand conformation polymorphism (SSCP) and a sequencing method. SSCP analysis showed that some infiltrating T cells in both glands expand clonally, suggesting that the cells proliferate by antigen-driven stimulation. Intriguingly, six to sixteen identical T cell receptor (TCR) Vbeta genes were commonly found in lacrimal glands and labial salivary glands from individual patients. This indicates that some T cells infiltrating into both glands recognize the shared epitopes on autoantigens. Moreover, highly conserved amino acid sequence motifs were found in the TCR CDR3 region bearing the same TCR Vbeta family gene from four SS patients, supporting the notion that the shared epitopes on antigens are limited. In conclusion, these findings suggest that some autoreactive T cells infiltrating into the lips and eyes recognized restricted epitopes of a common autoantigen in patients with SS.


Assuntos
Aparelho Lacrimal/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Glândulas Salivares/imunologia , Síndrome de Sjogren/genética , Síndrome de Sjogren/imunologia , Linfócitos T/imunologia , Sequência de Aminoácidos , Autoantígenos , Sequência de Bases , Biópsia , Southern Blotting , Células Clonais , Antígenos HLA-DQ/análise , Antígenos HLA-DR/análise , Humanos , Aparelho Lacrimal/patologia , Dados de Sequência Molecular , Família Multigênica , Sondas de Oligonucleotídeos , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Glândulas Salivares/patologia , Síndrome de Sjogren/patologia
10.
J Rheumatol ; 22(11): 2092-9, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8596150

RESUMO

OBJECTIVE: To identify the self-antigens recognized by autoreactive T cells in labial salivary glands from patients with Sjõgren's syndrome (SS). METHODS: T cells lines were established from infiltrating T cells in the labial salivary glands from 6 patients with SS, using interleukin 2 and phytohemagglutinin. Bulk cultured T cells and T cell lines were examined for the proliferative response to recombinant Ro(SSA) 52 kDa and SSB proteins. The usage of T cell receptor (TCR) V beta and V alpha genes from Ro(SSA) 52kDa reactive T cells was analyzed by family polymerase chain reaction. The sequences of complementary determining region 3 of TCR V beta genes were also examined. RESULTS: Three of 6 bulk cultured T cells and 4 of 16 T cell lines showed a significant proliferative response to Ro(SSA) 52 kDa protein. All T cell lines represented CD4+ alpha beta T cells by flow cytometry analysis. All 4 RO(SSA) 52 kDa reactive T cell lines utilized the V beta 2 gene and 3 lines used the V beta 13 gene, suggesting preferential usage of the V beta 2 and the V beta 13 genes in Ro(SSA) 52 kDa reactive T cells. Junctional sequences of TCR V beta genes from Ro(SSA) 52 kDa reactive T cell lines showed the conserved amino acid sequences in CDR3 region. CONCLUSION: These findings support the notion that Ro(SSA) 52 kDa is a possible autoantigen recognized by autoreactive T cells and that limited epitope is present on the Ro(SSA) 52 kDa antigen.


Assuntos
Autoantígenos/imunologia , Lábio , RNA Citoplasmático Pequeno , Ribonucleoproteínas/imunologia , Glândulas Salivares/imunologia , Síndrome de Sjogren/imunologia , Linfócitos T/imunologia , Sequência de Aminoácidos , Sequência de Bases , Antígenos CD4/imunologia , Divisão Celular , Linhagem Celular , Genes , Humanos , Sondas Moleculares/genética , Dados de Sequência Molecular , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Síndrome de Sjogren/patologia , Linfócitos T/patologia
11.
Nihon Rinsho ; 53(10): 2395-400, 1995 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-8531344

RESUMO

Sjögren's syndrome (SS) is an autoimmune disease characterized by lymphocytic infiltration into lachrymal and salivary glands leading to symptomatic dye eyes and mouth. Immunohistological studies have clarified that the majority of infiltrating lymphocytes around the lachrymal glands and labial salivary glands are CD4 positive alpha beta T cells. To analyze the nature of T cells in lachrymal glands and labial salivary glands, we examined TCR V beta genes of infiltrating T cells into both glands from SS patients, using PCR-SSCP and sequencing methods. The results showed the following two findings. 1) Some of T cells infiltrating in both glands expand clonally, suggesting that these cells proliferate by antigen-driven stimulation. 2) The common T cells accumulated in lachrymal and labial salivary glands. In conclusion, autoreactive T cells in lips and eyes should recognize the same epitopes of autoantigen in individual patients with SS. Further analysis on autoantigen using T cell lines from labial salivary glands supports the notion that Ro/SS-A 52 kD is a possible autoantigen recognized by autoreactive T cells.


Assuntos
Receptores de Antígenos de Linfócitos T alfa-beta/genética , Síndrome de Sjogren/imunologia , Autoantígenos , Linfócitos T CD4-Positivos/imunologia , Humanos , Aparelho Lacrimal/citologia , Reação em Cadeia da Polimerase , Glândulas Salivares/citologia
12.
Int Immunol ; 6(9): 1445-9, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7819154

RESUMO

beta 2-Microglobulin (beta 2m)-deficient non-obese diabetic (NOD) mice were established by crossing beta 2m-deficient 129/Sv mice with NOD mice, and used to examine the possible involvement of MHC class I molecules and CD8+ T cells in the development of insulitis and diabetes. In these mice, MHC class I molecules were not expressed, resulting in no generation of CD8+ T cells. None of eight lines of beta 2m-deficient NOD mice (-/-) established developed overt diabetes by 32 weeks, while control littermates (+/+) became diabetic by 22 weeks. histological studies showed no significant lymphocyte infiltration of the islets (insulitis score: 0.03 +/- 0.03) in any of the beta 2m-deficient NOD mice (-/-) compared with littermate NOD mice (+/+) with overt insulitis (1.42 +/- 0.28). These findings support the notion that the expression of MHC class I molecules and/or CD8+ T cells plays an essential role in the infiltration of CD4+ T cells in islets as well as the development of diabetes in NOD mice.


Assuntos
Diabetes Mellitus Tipo 1/prevenção & controle , Ilhotas Pancreáticas/patologia , Pancreatopatias/prevenção & controle , Microglobulina beta-2/deficiência , Animais , Sequência de Bases , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Primers do DNA , Diabetes Mellitus Tipo 1/imunologia , Feminino , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe II/genética , Ilhotas Pancreáticas/imunologia , Complexo Principal de Histocompatibilidade/imunologia , Masculino , Camundongos , Camundongos Endogâmicos NOD , Dados de Sequência Molecular , Pancreatopatias/imunologia , Pancreatopatias/patologia , Microglobulina beta-2/genética
13.
Br J Rheumatol ; 33(5): 420-4, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8173843

RESUMO

To identify genetic factors that play a role in the pathogenesis of patients with SS over-representing V beta 2 and V beta 13 genes in the lips, HLA-DR and -DQ alleles of 10 primary SS patients with predominant expression of V beta 2 and V beta 13 genes in the lips were analysed, using the polymerase chain reaction (PCR) and sequence specific oligonucleotide probes. The CDR3 amino acid sequences of cDNA clones encoding V beta 2 and V beta 13 genes were also determined by PCR. The results showed that the DRB4*0101 allele was significantly increased (80%) and that the frequency of DRB3 allele was decreased (0%) when compared to findings in healthy subjects (35.6 and 26%, respectively). Sequencing analyses demonstrated that 75% of V beta 2 cDNA clones and 87% of V beta 13 cDNA clones had a glutamine residue at position 106, in the CDR13 region. Moreover, the conserved sequences (Y*TLRNEQ) in the CDR3 of V beta 13-positive T cell were detected in two different clones (27%) from the two individual SS patients. These findings suggest that the decreased DRB3 and increased DRB4*0101 alleles may be associated with the antigens recognized by V beta 2- and V beta 13-positive T cells.


Assuntos
Antígenos HLA-DQ/genética , Antígenos HLA-DR/genética , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Glândulas Salivares Menores/imunologia , Síndrome de Sjogren/genética , Alelos , Sequência de Aminoácidos , Sequência de Bases , DNA Complementar/genética , Humanos , Lábio , Dados de Sequência Molecular , Síndrome de Sjogren/imunologia
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