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1.
Arthritis Care Res (Hoboken) ; 64(4): 475-87, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22563590

RESUMO

OBJECTIVE: We propose new classification criteria for Sjögren's syndrome (SS), which are needed considering the emergence of biologic agents as potential treatments and their associated comorbidity. These criteria target individuals with signs/symptoms suggestive of SS. METHODS: Criteria are based on expert opinion elicited using the nominal group technique and analyses of data from the Sjögren's International Collaborative Clinical Alliance. Preliminary criteria validation included comparisons with classifications based on the American­European Consensus Group (AECG) criteria, a model-based "gold standard"obtained from latent class analysis (LCA) of data from a range of diagnostic tests, and a comparison with cases and controls collected from sources external to the population used for criteria development. RESULTS: Validation results indicate high levels of sensitivity and specificity for the criteria. Case definition requires at least 2 of the following 3: 1) positive serum anti-SSA and/or anti-SSB or (positive rheumatoid factor and antinuclear antibody titer >1:320), 2) ocular staining score >3, or 3) presence of focal lymphocytic sialadenitis with a focus score >1 focus/4 mm2 in labial salivary gland biopsy samples. Observed agreement with the AECG criteria is high when these are applied using all objective tests. However, AECG classification based on allowable substitutions of symptoms for objective tests results in poor agreement with the proposed and LCA-derived classifications. CONCLUSION: These classification criteria developed from registry data collected using standardized measures are based on objective tests. Validation indicates improved classification performance relative to existing alternatives, making them more suitable for application in situations where misclassification may present health risks.


Assuntos
Fenótipo , Síndrome de Sjogren/classificação , Síndrome de Sjogren/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antinucleares/sangue , Biópsia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Fator Reumatoide/sangue , Glândulas Salivares/patologia , Sensibilidade e Especificidade , Sialadenite/patologia , Sociedades Médicas , Estados Unidos
2.
Ann Rheum Dis ; 68(8): 1310-5, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18701557

RESUMO

BACKGROUND: Mikulicz's disease (MD) has been considered as one manifestation of Sjögren's syndrome (SS). Recently, it has also been considered as an IgG(4)-related disorder. OBJECTIVE: To determine the differences between IgG(4)-related disorders including MD and SS. METHODS: A study was undertaken to investigate patients with MD and IgG(4)-related disorders registered in Japan and to set up provisional criteria for the new clinical entity IgG(4)-positive multiorgan lymphoproliferative syndrome (IgG(4)+MOLPS). The preliminary diagnostic criteria include raised serum levels of IgG(4) (>135 mg/dl) and infiltration of IgG(4)(+) plasma cells in the tissue (IgG(4)+/IgG+ plasma cells >50%) with fibrosis or sclerosis. The clinical features, laboratory data and pathologies of 64 patients with IgG(4)+MOLPS and 31 patients with typical SS were compared. RESULTS: The incidence of xerostomia, xerophthalmia and arthralgia, rheumatoid factor and antinuclear, antiSS-A/Ro and antiSS-B/La antibodies was significantly lower in patients with IgG(4)+MOLPS than in those with typical SS. Allergic rhinitis and autoimmune pancreatitis were significantly more frequent and total IgG, IgG(2), IgG(4) and IgE levels were significantly increased in IgG(4)+MOLPS. Histological specimens from patients with IgG(4)+MOLPS revealed marked IgG(4)+ plasma cell infiltration. Many patients with IgG(4)+MOLPS had lymphocytic follicle formation, but lymphoepithelial lesions were rare. Few IgG(4)+ cells were seen in the tissue of patients with typical SS. Thirty-eight patients with IgG(4)+MOLPS treated with glucocorticoids showed marked clinical improvement. CONCLUSION: Despite similarities in the involved organs, there are considerable clinical and pathological differences between IgG(4)+MOLPS and SS. Based on the clinical features and good response to glucocorticoids, we propose a new clinical entity: IgG(4)+MOLPS.


Assuntos
Imunoglobulina G/análise , Transtornos Linfoproliferativos/imunologia , Doença de Mikulicz/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Diagnóstico Diferencial , Feminino , Glucocorticoides/uso terapêutico , Humanos , Aparelho Lacrimal/patologia , Transtornos Linfoproliferativos/diagnóstico , Transtornos Linfoproliferativos/tratamento farmacológico , Transtornos Linfoproliferativos/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doença de Mikulicz/diagnóstico , Doença de Mikulicz/tratamento farmacológico , Doença de Mikulicz/patologia , Prednisolona/uso terapêutico , Estudos Retrospectivos , Glândulas Salivares Menores/patologia , Síndrome de Sjogren/diagnóstico , Síndrome de Sjogren/imunologia , Síndrome de Sjogren/patologia , Síndrome , Adulto Jovem
3.
Clin Exp Immunol ; 150(2): 279-84, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17937678

RESUMO

The aim of this study was to clarify the nature of the clonal lymphocyte infiltration in Sjögren's syndrome (SS) patients associated with lymphoproliferative disorders. We examined B cell clonality in lymphoproliferative tissues from six primary SS patients associated with lymphoproliferative disorders or lymphoma by cloning and sequencing of the gene rearrangement of the immunoglobulin heavy chain complementarity determining region 3 (IgVH-CDR3). Three patients with sequential observation showed progressional clonal expansion with the presence of the same subclone in different tissues during the course of disease. Among them, one patient developed mucosa-associated lymphoid tissue (MALT) lymphoma in glandular parotid. The other three SS patients concomitant with malignant B cells lymphomas showed different clonal expansion of B cells between nodal sites and salivary glands. The cloanality analysis indicated that monoclonal B cell population could spread from one glandular site to another site during the course of SS, suggesting that the malignant clone may arise from the general abnormal microenvironment, not restricted to the glandular tissue, in some SS patients.


Assuntos
Linfócitos B/patologia , Transtornos Linfoproliferativos/patologia , Células-Tronco Neoplásicas/patologia , Síndrome de Sjogren/patologia , Idoso , Idoso de 80 Anos ou mais , Sequência de Aminoácidos , Regiões Determinantes de Complementaridade/genética , Progressão da Doença , Feminino , Rearranjo Gênico de Cadeia Pesada de Linfócito B , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Linfoma de Células B/patologia , Linfoma de Zona Marginal Tipo Células B/patologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase/métodos
4.
Clin Exp Immunol ; 142(1): 148-54, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16178869

RESUMO

The objective of this study was to detect autoantibodies against granzyme B cleavage products in sera from patients with primary Sjögren's syndrome (SS). Cell lysates derived from human salivary gland (HSG) cell lines were incubated with granzyme B. The susceptibility to the generation of cleavage fragments of SS autoantigens was assayed by immunoblotting using sera from 57 primary SS patients, 17 primary SS patients with malignant lymphoma (ML), 28 systemic lupus erythematosus (SLE) patients, and 20 healthy controls. A 27 kD protein was recognized by serum autoantibodies in 8 (14.0%) of 57 primary SS patients, 5 (29.4%) of 17 SS patients with ML, 2 (7.1%) of 28 SLE patients, but not in 20 normal subjects. This protein was recognized by anti-SSB (La) monoclonal antibodies. Granzyme B-treated recombinant La protein was also shown to migrate as a discrete 27 kD protein by SDS PAGE. Blocking studies demonstrated the existence of an apoptosis-specific B cell epitope present in sera from 2 of 8 primary SS patients and in 2 of 5 primary SS patients with ML which recognized the 27 kD protein. Granzyme B-induced La fragments are generated during cytotoxicity in vitro. This is the first report describing autoantibodies in sera from primary SS patients that specifically recognize fragments of the La protein that are produced by the granzyme B protease.


Assuntos
Apoptose/imunologia , Autoanticorpos/imunologia , Autoantígenos/imunologia , Ribonucleoproteínas/imunologia , Serina Endopeptidases/imunologia , Síndrome de Sjogren/imunologia , Adulto , Idoso , Autoanticorpos/sangue , Linfócitos B/imunologia , Linhagem Celular , Sistema Livre de Células/imunologia , Citotoxicidade Imunológica/imunologia , Feminino , Granzimas , Humanos , Lúpus Eritematoso Sistêmico/imunologia , Linfoma/imunologia , Masculino , Pessoa de Meia-Idade , Antígeno SS-B
5.
Eur J Haematol ; 67(3): 194-8, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11737254

RESUMO

A 43-yr-old Japanese woman presented with mild anemia, leukocytosis and splenomegaly in May 1984. Splenomegaly and anemia gradually progressed. Sixteen years later, in October 2000, she developed inguinal lymphadenopathy. Biopsy of the lymph node revealed infiltration of blasts, megakaryocytes, fibroblasts and myeloid cells. Large blasts with basophilic cytoplasm with cytoplasmic projections appeared in the peripheral blood. These blasts were negative in peroxidase stain, positive in acid phosphatase and weakly positive in periodic acid-Schiff stain. Immunohistochemical staining with monoclonal antibodies revealed that these blasts were positive with anti-CD41 (glycoprotein IIb/IIIa) and negative with other monoclonal antibodies. So diagnosis of granulocytic sarcoma in megakaryoblastic transformation from chronic idiopathic myelofibrosis was made. A cytogenetic study revealed that bone marrow cells were 46,XX del(13)(q?) initially and additional abnormalities including der(5,5,11)(q11;q13)ins(5;?)(q11;?) were found when she developed megakaryoblastic transformation. Granulocytic sarcoma of megakaryoblastic transformation from chronic idiopathic myelofibrosis is a rare event. Immunophenotyping with monoclonal antibody for CD41(glycoprotein IIb/IIIa) confirmed the diagnosis.


Assuntos
Leucemia Megacarioblástica Aguda/etiologia , Mielofibrose Primária/complicações , Sarcoma Mieloide/etiologia , Diferenciação Celular , Transformação Celular Neoplásica , Doença Crônica , Feminino , Humanos , Leucemia Megacarioblástica Aguda/patologia , Linfonodos/patologia , Megacariócitos/patologia , Pessoa de Meia-Idade , Mielofibrose Primária/patologia , Sarcoma Mieloide/patologia
6.
J Rheumatol ; 28(10): 2238-44, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11669163

RESUMO

OBJECTIVE: To determine whether the clinical and laboratory characteristics of anticentromere antibody (ACA) positive, anti-SSA/Ro antibody (SSA) negative primary Sjogren's syndrome (SS) differ from SSA positive, ACA negative primary SS. METHODS: Twelve patients with ACA positive primary SS (ACA SS) and 19 patients with SSA positive primary SS (SSA SS) were examined. We compared the age, laboratory data, proportion with Raynaud's phenomenon (RP), activity of natural killer cells (NK), titer of antibodies against Epstein-Barr virus, and histological findings of minor labial salivary glands. The presence of anti-chromo antibodies (AChA) was evaluated by immunoblotting of patients' sera. RESULTS: The mean age of the ACA SS group was higher than that of the SSA SS group (p < 0.05). Serum IgG level was lower in ACA SS than in SSA SS (p < 0.0001). Serum IgG level of the ACA SS group with one exception was close to the normal range. Leukocytopenia was less frequently observed in ACA SS than in SSA SS (p < 0.05). RP was seen more frequently in the ACA SS group than the SSA SS group (p < 0.05). NK activity of the ACA SS group was higher than that of the SSA SS group (p < 0.05). Most of the ACA SS patients' NK activity was normal, in contrast to the tendency for NK activity in SS to be low. Virus capsid antigen IgA titer of the ACA SS group was lower than that of the SSA SS group (p < 0.05). Histological findings of minor labial salivary glands of both groups showed a similar severity of lymphocytic infiltrates, destruction of normal structures, and pattern of infiltrating lymphocyte subsets. AChA was positive in 11 of the 12 sera of ACA SS patients. CONCLUSION: The results confirm that ACA positive primary SS differs from SSA positive classic SS in several significant respects.


Assuntos
Autoanticorpos/sangue , Centrômero/imunologia , Síndrome de Sjogren/imunologia , Idoso , Idoso de 80 Anos ou mais , Antígenos Virais/imunologia , Autoantígenos/imunologia , Feminino , Herpesvirus Humano 4/imunologia , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Linfócitos/imunologia , Pessoa de Meia-Idade , Ribonucleoproteínas/imunologia , Glândulas Salivares Menores/imunologia , Glândulas Salivares Menores/patologia , Síndrome de Sjogren/patologia , Antígeno SS-B
7.
Int J Hematol ; 73(2): 226-9, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11372736

RESUMO

Cyclosporin A (CsA) is used to prevent rejection in transplantation and to treat autoimmune and hematologic diseases such as aplastic anemia. However, the tumor growth-promoting effect of CsA remains controversial. We report the case of a 24-year-old man who developed acute lymphoblastic leukemia of precursor-T-cell origin after 75 months of treatment with CsA for aplastic anemia. The surface antigen phenotype of his leukemic cells was CD2+, CD3+, CD5+, CD7+, CD4-, CD8-, CD10-, CD20-, CD34-, CD41-, and CD56-. Southern blot analysis revealed a monoclonal rearrangement of T-cell receptor-Jgamma nongermline fragments in HindIII digestion.


Assuntos
Anemia Aplástica/tratamento farmacológico , Ciclosporina/efeitos adversos , Leucemia de Células T/induzido quimicamente , Leucemia-Linfoma Linfoblástico de Células Precursoras/induzido quimicamente , Adolescente , Anemia Aplástica/complicações , Transformação Celular Neoplásica/efeitos dos fármacos , Células Clonais , Ciclosporina/administração & dosagem , Rearranjo Gênico , Humanos , Imunofenotipagem , Leucemia de Células T/patologia , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Receptores de Antígenos de Linfócitos T/genética
8.
J Comput Assist Tomogr ; 25(2): 262-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11242226

RESUMO

PURPOSE: The purpose of this work was to compare the diagnostic accuracy of MR sialography with that of salivary gland scintigraphy in Sjögren syndrome. METHOD: One hundred thirty patients clinically suspected of having Sjögren syndrome were examined by MR sialography and salivary gland scintigraphy. A labial gland biopsy was performed in all patients. Imaging findings of MR sialography and salivary gland scintigraphy were compared with the results of labial gland biopsy. RESULTS: From the results of labial gland biopsy, the diagnosis of Sjögren syndrome was established in 80 patients. Abnormally high T2 signal intensity areas on MR sialography and decreased uptake and delayed excretion of [(99m)Tc]pertechnetate on salivary gland scintigraphy were well seen in patients with Sjögren syndrome. For the diagnosis of Sjögren syndrome, salivary gland scintigraphy showed higher sensitivity than MR sialography. On the other hand, MR sialography showed higher specificity and positive predictive value (PPV) than salivary gland scintigraphy. Overall diagnostic accuracy was 83% for MR sialography and 72% for salivary gland scintigraphy. CONCLUSION: The high PPV of MR sialography suggests that MR sialography is the preferred imaging modality in patients suspected of having Sjögren syndrome.


Assuntos
Imageamento por Ressonância Magnética , Glândulas Salivares/diagnóstico por imagem , Glândulas Salivares/patologia , Síndrome de Sjogren/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Criança , Glândulas Exócrinas/patologia , Feminino , Humanos , Lábio/patologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Cintilografia , Compostos Radiofarmacêuticos , Sensibilidade e Especificidade , Síndrome de Sjogren/diagnóstico por imagem , Síndrome de Sjogren/patologia , Pertecnetato Tc 99m de Sódio
9.
Nihon Rinsho Meneki Gakkai Kaishi ; 24(4): 160-7, 2001 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-16578967

RESUMO

A 64-year-old female was admitted in May 1997, because of salivary gland swelling. Histology of the right parotid gland revealed malignant lymphoma, diffuse medium-sized B-cell type, and she was treated with local radiotherapy and chemotherapy. She was rehospitalized in April 1998, because of recurrence of lymphoma in the stomach and the sigmoid colon. She had splenomegaly and lymphadenopathy (neck and inguinal). Laboratory findings revealed marked elevation of rheumatoid factor and RNA of hepatitis C virus. A diagnosis of Sjogren's syndrome was made by dryness and the histological findings of labial biopsy. Marginal zone B-cell lymphoma mainly consisted of centrocyte-like cells and lymphoepithelial lesions, and CD 20 and IgM-kappa were positive with immunohistochemical staining. Lymphoma involved the gut and spleen. We discuss the correlation of malignant lymphoma with Sjogren's syndrome and HCV infection.


Assuntos
Hepatite C/complicações , Linfoma de Células B/etiologia , Neoplasias Parotídeas/etiologia , Síndrome de Sjogren/complicações , Antígenos CD20/metabolismo , Evolução Fatal , Feminino , Trato Gastrointestinal/patologia , Humanos , Imuno-Histoquímica , Linfoma de Células B/metabolismo , Linfoma de Células B/patologia , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Recidiva Local de Neoplasia , Neoplasias Parotídeas/metabolismo , Neoplasias Parotídeas/patologia , Baço/patologia
12.
Rinsho Ketsueki ; 41(1): 54-60, 2000 Jan.
Artigo em Japonês | MEDLINE | ID: mdl-10695400

RESUMO

After 2 years of steroid therapy that had effectively controlled her systemic lupus erythematosus, a 37-year-old woman presented with fever, erythema (face, upper chest), and low CH50. Increased oral steroid (prednisolone from 15 mg to 40 mg) and intravenous methylprednisolone (mPSL) (80 mg for 3 days) alleviated these symptoms except for the fever. Subsequently, the patient's fever worsened and leukocytopenia, abnormal liver function, lymphadenopathy (neck, axilla), and salivary gland swelling developed. Lymph node histology revealed features characteristic of Kikuchi-Fujimoto's disease (KFD). Laboratory examinations showed WBC 600/microliter, Hb 9.5 g/dl, platelets 90,000/microliter, GOT 766 IU/l, GPT 646 IU/l, LDH 4,228 IU/l, TG 1,622 mg/dl, and ferritin 6,330 ng/ml. Serum interferon gamma was also elevated (673 U/ml). Because a bone marrow smear revealed hemophagocytosis, mPSL pulse therapy (1 g for 3 days) was started for treatment of hemophagocytic syndrome. The fever promptly disappeared, and the patient's clinical symptoms resolved within 2 weeks. The abnormal laboratory data related to KFD and hemophagocytosis returned to normal within 4 weeks after the initiation of mPSL pulse therapy. We speculated that the hemophagocytosis and salivary gland involvement in this patient were also symptoms of KFD. This case indicated that corticosteroid pulse therapy is effective for KFD with serious clinical symptoms.


Assuntos
Linfadenite Histiocítica Necrosante/etiologia , Histiocitose de Células não Langerhans/etiologia , Lúpus Eritematoso Sistêmico/complicações , Sialadenite/etiologia , Adulto , Feminino , Linfadenite Histiocítica Necrosante/tratamento farmacológico , Histiocitose de Células não Langerhans/tratamento farmacológico , Humanos , Prednisolona/administração & dosagem , Pulsoterapia , Sialadenite/tratamento farmacológico , Resultado do Tratamento
15.
Virchows Arch ; 436(2): 109-14, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10755599

RESUMO

There is growing evidence that nitric oxide (NO) has an important role in tumor growth. However, information on the expression of NO synthase (NOS) in colorectal cancers is scanty. We therefore investigated the distribution and expression of NOS in human colorectal cancers. The expression of three types of NOS, inducible (iNOS), endothelial (eNOS) and neuronal (nNOS), was examined by immunohistochemistry in 25 cases of colorectal cancer. The expression of iNOS was also investigated at the mRNA level using the reverse transcriptase polymerase chain reaction (RT-PCR) in 6 cases. Correlations were made between iNOS expression and the histopathological findings. Immunoreactive iNOS was detected in the tumor cells in 22 cases (88%) with diffuse cytoplasmic reactions. Expression of iNOS-mRNA detected by RT-PCR in three tumor tissues was over five-fold that in normal mucosa. Intensified immunoreactivity of iNOS was associated with vascular invasion. iNOS expression did not correlate with pathological staging, tumor size, lymph node metastasis, p53 expression or tumor vessel density. Immunoreactive eNOS stained more strongly in the endothelial cells of microvessels within and around the tumor than in the areas remote from the tumor. There is enhanced expression of iNOS and eNOS in human colorectal cancers, which may correlate with tumor growth and vascular invasion.


Assuntos
Neoplasias Colorretais/enzimologia , Óxido Nítrico Sintase/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Colo/enzimologia , Neoplasias Colorretais/patologia , Endotélio Vascular/enzimologia , Endotélio Vascular/patologia , Feminino , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase Tipo I , Óxido Nítrico Sintase Tipo II , Óxido Nítrico Sintase Tipo III , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , RNA Mensageiro/biossíntese , RNA Neoplásico/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína Supressora de Tumor p53/metabolismo
17.
Jpn J Cancer Res ; 90(8): 858-66, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10543258

RESUMO

To explore the role of cytokines in tumor development and clinical manifestations, we examined the expressions of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) in tumor tissues obtained from 57 patients with oral squamous cell carcinoma (OSCC) and their relationships to pathological grade and staging. Enzyme-linked immunosorbent assay on the tumor tissues demonstrated elevated concentrations of TNF-alpha and IL-6 proteins and upregulated mRNA levels were detected by the reverse transcription-polymerase chain reaction method when compared to those in normal control tissues. These cytokines and their transcripts were localized in stromal macrophages and in the tumor cells in particular of the front area of tumor tissues, possibly indicating active synthesis of these cytokines by tumor cells. Larger-sized tumors (T3, 4) contained significantly greater levels of IL-6 proteins than small-sized tumors (T1, 2) (P<0.05). The levels of these cytokines were significantly reduced in cases with effective pre-treatment with radiation or anti-cancer agents compared to those in the less effective group (P<0.05, grade IIa vs. grade IV for both TNF-alpha and IL-6). The present study thus demonstrated enhanced expression of cytokines in OSCC tissues.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Interleucina-6/biossíntese , Neoplasias Bucais/metabolismo , Fator de Necrose Tumoral alfa/biossíntese , Carcinoma de Células Escamosas/patologia , Citoplasma/metabolismo , Endotélio Vascular/metabolismo , Ensaio de Imunoadsorção Enzimática , Humanos , Imuno-Histoquímica , Hibridização In Situ , Neoplasias Bucais/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Estromais/metabolismo
18.
J Biol Chem ; 274(42): 30236-43, 1999 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-10514516

RESUMO

To elucidate the roles of SHP-2, we generated transgenic (Tg) mice expressing a dominant negative mutant lacking protein tyrosine phosphatase domain (DeltaPTP). On examining two lines of Tg mice identified by Southern blot, the transgene product was expressed in skeletal muscle, liver, and adipose tissues, and insulin-induced association of insulin receptor substrate 1 with endogenous SHP-2 was inhibited, confirming that DeltaPTP has a dominant negative property. The intraperitoneal glucose loading test demonstrated an increase in blood glucose levels in Tg mice. Plasma insulin levels in Tg mice after 4 h fasting were 3 times greater with comparable blood glucose levels. To estimate insulin sensitivity by a constant glucose, insulin, and somatostatin infusion, steady state blood glucose levels were higher, suggesting the presence of insulin resistance. Furthermore, we observed the impairment of insulin-stimulated glucose uptake in muscle and adipocytes in the presence of physiological concentrations of insulin. Moreover, tyrosine phosphorylation of insulin receptor substrate-1 and stimulation of phosphatidylinositol 3-kinase and Akt kinase activities by insulin were attenuated in muscle and liver. These results indicate that the inhibition of endogenous SHP-2 function by the overexpression of a dominant negative mutant may lead to impaired insulin sensitivity of glucose metabolism, and thus SHP-2 may function to modulate insulin signaling in target tissues.


Assuntos
Genes Dominantes , Glicogênio Sintase/metabolismo , Resistência à Insulina/genética , Proteínas Tirosina Fosfatases/genética , Animais , Ativação Enzimática , Glucose/metabolismo , Insulina/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular , Masculino , Camundongos , Camundongos Transgênicos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Músculo Esquelético/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 11 , Proteína Tirosina Fosfatase não Receptora Tipo 6 , Proteínas Tirosina Fosfatases/fisiologia , Transdução de Sinais
19.
Cancer Res ; 59(17): 4222-4, 1999 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-10485460

RESUMO

Activation of c-src, a cellular human gene homologous in sequence to the v-src gene of Rous sarcoma virus, had been thought to play an important role in the progression of several types of human cancers, without having undergone any genetic changes. However, recently truncating mutations at codon 531 of the c-src gene were reported in 12% of the advanced colon cancers, and it was also demonstrated that this change was activating, transforming, tumorigenic, and metastasis promoting. To investigate whether the codon 531-specific mutation could be involved in the carcinogenesis of colorectal cancer in the Japanese and Caucasian populations, we examined a total of 479 advanced colorectal cancers from 421 Japanese patients (46 of them with liver or lung metastases) and from 58 Caucasian patients (11 of them with liver metastases). Using the PCR-RFLP assay and additional single-strand conformation polymorphism analysis, we detected no genetic alteration in any of the advanced colorectal cancers. Our results suggest that the codon 531-specific mutational activation of c-src is unlikely to play a significant role in the malignant progression of colorectal cancers among most Japanese and Caucasian patients.


Assuntos
Códon , Neoplasias Colorretais/genética , Genes src , Mutação , Povo Asiático , Neoplasias Colorretais/etnologia , Humanos , Japão , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , População Branca
20.
Int J Hematol ; 69(3): 174-9, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10222656

RESUMO

The association of Epstein-Barr virus (EBV) with Sjögren's syndrome (SS) is controversial. Reports suggest there is an increased risk of developing lymphoid malignancy in SS. Among our 425 cases of SS, 17 cases of malignant lymphoma (4%), 16 cases of non-Hodgkin's lymphoma (NHL), and 1 case of Hodgkin's disease were found. We looked for an association between EBV and 14 cases of NHL, 13 cases of B-cell lymphoma, and 1 case of T-cell lymphoma in which tissue specimens were available. Epstein-Barr virus-encoded RNA in situ hybridization study and polymerase chain reaction (PCR) study using primers to detect the Bam HI W fragment of EBV with DNA extracts were positive in 2 NHLs: 1 diffuse, large B-cell-type lymphoma, 1 out of 13 cases (8%) of B-cell lymphoma, and 1 angioimmunoblastic T-cell lymphoma with dysproteinemia. In the Bam HI W PCR study of DNA obtained from the labial small salivary glands of 55 cases with SS, 3 cases (5%) were positive. These 3 cases were not associated with malignant lymphoma. Our study revealed that EBV association in SS did not lead to an increased occurrence.


Assuntos
Herpesvirus Humano 4/genética , Doença de Hodgkin/virologia , Linfoma não Hodgkin/virologia , RNA Viral/análise , Síndrome de Sjogren/virologia , Idoso , Linfoma de Burkitt/virologia , Feminino , Herpesvirus Humano 4/isolamento & purificação , Herpesvirus Humano 4/patogenicidade , Doença de Hodgkin/etiologia , Humanos , Imuno-Histoquímica , Hibridização In Situ , Linfoma não Hodgkin/etiologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Síndrome de Sjogren/complicações
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