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1.
Clin Microbiol Infect ; 20(1): O50-7, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23889746

RESUMO

Invasive candidiasis is a life-threatening infection in patients with haematological malignancies. The objective of our study was to determine the incidence, microbiological characteristics and clinical outcome of candidaemia among hospitalized adult patients with haematological malignancies. This is a population-based, prospective, multicentre study of patients ≥ 18 years admitted to haematology and/or haematopoietic stem cell transplantation units of nine tertiary care Greek hospitals from January 2009 through to February 2012. Within this cohort, we conducted a nested case-control study to determine the risk factors for candidaemia. Stepwise logistic regression was used to identify independent predictors of 28-day mortality. Candidaemia was detected in 40 of 27,864 patients with haematological malignancies vs. 967 of 1,158,018 non-haematology patients for an incidence of 1.4 cases/1000 admissions vs. 0.83/1000 respectively (p <0.001). Candidaemia was caused predominantly (35/40, 87.5%) by non-Candida albicans species, particularly Candida parapsilosis (20/40, 50%). In vitro resistance to at least one antifungal agent was observed in 27% of Candida isolates. Twenty-one patients (53%) developed breakthrough candidaemia while receiving antifungal agents. Central venous catheters, hypogammaglobulinaemia and a high APACHE II score were independent risk factors for the development of candidaemia. Crude mortality at day 28 was greater in those with candidaemia than in control cases (18/40 (45%) vs. 9/80 (11%); p <0.0001). In conclusion, despite antifungal prophylaxis, candidaemia is a relatively frequent infection associated with high mortality caused by non-C. albicans spp., especially C. parapsilosis. Central venous catheters and hypogammaglobulinaemia are independent risk factors for candidaemia that provide potential targets for improving the outcome.


Assuntos
Candida/classificação , Candidemia/epidemiologia , Candidemia/etiologia , Neoplasias Hematológicas/complicações , Adolescente , Adulto , Agamaglobulinemia/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Antifúngicos/uso terapêutico , Candidemia/microbiologia , Candidemia/mortalidade , Estudos de Casos e Controles , Cateteres Venosos Centrais/efeitos adversos , Feminino , Grécia/epidemiologia , Hospitalização , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Adulto Jovem
2.
Autoimmune Dis ; 2011: 841325, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21687651

RESUMO

We report a case of multiple autoimmunity consisting of the presence of autoimmune haemolytic anaemia (AIHA), antimitochondrial antibodies (AMAs), and antiphospholipid antibodies (APLAbs) as the presenting manifestations of an extrahepatic B-non-Hodgkin lymphoma (B-NHL) in a 63-year-old woman. The patient presented with fatigue attributed to severe AIHA. Due to increased serum IgM and γ-GT levels, an investigation for AMA was performed, which proved positive with anti-M2 specificity. A prolongation of activated partial thromboplastin time (aPTT) led to the determination of APLAbs (lupus anticoagulant and other APLAbs) which were also positive. Bone marrow biopsy in combination with immmunohistochemical studies established the diagnosis of lymphoplasmacytic B-NHL. Ten months later, B-NHL was in remission while AMA and APLAbs were still positive. In conclusion, we documented the coexistence of multiple autoimmune reactions together with B-NHL highlighting the possible common pathogenetic pathways of the two entities.

3.
Case Rep Med ; 2010: 421239, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21274282

RESUMO

Acute panmyelosis with myelofibrosis (APMF) is a rare, fatal hematological neoplasm that is characterized by the acute onset of cytopenias and fibrosis in the bone marrow in the absence of splenomegaly or fibrosis-related morphological changes in the RBCs. We present the case of a 59-year-old female who presented with a two-month history of anemia, leucopenia and a normal platelet count. The marrow was heavily fibrotic, and no aspirate material could be obtained; the biopsy showed extensive infiltration with small to medium size megakaryocytes, dysplastic changes in the erythroid compartment, and left shift in the myeloid cells. The patient was treated for four months with anabolic steroids (Danazol), growth factors and received regular blood transfusions. At 4 months after diagnosis, the patient was started on Lenalidomide, 10 mg/day for a 21-d-course along with growth factor support. At 6 months after treatment, the patient was transfusion-independent, had normalized blood counts, and, at 32 months on continuous lenalidomide treatment, her needs for growth factor support have been minimized. Repeat bone marrow biopsies showed a patchy distribution of fibrosis with areas of normal cellularity and morphology. To our knowledge, this is the first case for a medication that could reverse the fatal outcome of APMF.

4.
Ann Hematol ; 85(4): 250-6, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16416114

RESUMO

In elderly patients with secondary leukemia, poor therapeutic response and low overall survival have been attributed mainly to age and to the primary resistance of leukemic cells to chemotherapy. Modulation of resistance has been attempted in different studies, but the results have been contradictory. We conducted an open, randomized multicenter clinical trial involving patients more than 60 years old with secondary leukemia preceded by a myelodysplastic syndrome. The induction chemotherapy regimen included idarubicin, cytarabine, and etoposide (group A); randomization involved simultaneous administration of cyclosporin-A per os (group B). Fifty-five patients were evaluated, 26 in group A and 29 in group B. Overall complete remission was achieved in 40% of the patients, 27% vs 52% in groups A and B, respectively (p=0.01). Leukemia-free survival was more favorable in patients who received cyclosporin-A, 12 vs 7 months for groups B and A, respectively (p=0.03). In a follow up period of 30 months, 7 out of 55 patients (13%) were alive, 4 of whom were in complete remission. Five out of the 7 alive patients were randomized in group B and had received cyclosporin-A. Treatment failure was higher in group A [19 of 26 patients (73%)] than in group B with CsA [14 of 29 patients (48%)] (p<0.0001). Treatment-related toxicity/mortality was 13%. Modulation of drug resistance by CsA in elderly people suffering from secondary acute leukemia may improve the outcome of chemotherapy without increasing drug toxicity and treatment-related mortality.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ciclosporina/administração & dosagem , Leucemia Mieloide/tratamento farmacológico , Segunda Neoplasia Primária/tratamento farmacológico , Doença Aguda , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Ciclosporina/efeitos adversos , Ciclosporina/uso terapêutico , Citarabina/administração & dosagem , Citarabina/uso terapêutico , Interpretação Estatística de Dados , Intervalo Livre de Doença , Etoposídeo/administração & dosagem , Etoposídeo/uso terapêutico , Feminino , Seguimentos , Grécia , Humanos , Idarubicina/administração & dosagem , Idarubicina/uso terapêutico , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Indução de Remissão , Sociedades Médicas , Análise de Sobrevida , Resultado do Tratamento
6.
J BUON ; 8(4): 341-50, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-17472275

RESUMO

PURPOSE: Aberrant methylation, as an epigenetic phenomenon, may precede and regulate the expression of genes involved in transformation mechanisms that lead to leukemogenesis of hemopoietic cells. The genes involved mostly encode transcription factors and cell cycle specific inhibitors. The aim of this project was to study the DNA methylation pattern of c-myc, c-fos and p53 in myelodysplastic syndromes (MDS) and in acute non-lymphocytic leukemias (ANLL). PATIENTS AND METHODS: DNA was isolated from the monocyte cell layer harvested from bone marrow or peripheral blood samples of 44 patients suffering from MDS and ANLL. Genomic DNA was digested with methylation-specific enzymes, and was electrophoresed and hybridized with probes specific for human c-myc, c-fos and p53 genes. RESULTS: In MDS, the c-myc gene in exons 2 and 3 was regionally hypomethylated, whereas exon 2 in ANLL was hypermethylated and exon 3 hypomethylated. The c-fos gene was hypomethylated in ANLL type 4 and presented aberrant hypomethylation in the different types of MDS. The p53 anti-oncogene appeared extensively hypomethylated in MDS. CONCLUSION: Aberrant DNA methylation pattern of the c-myc, c-fos and p53 tumor suppressor gene seems to be a primary event in the transformation process from myelodysplasia to acute leukemia, affecting their expression, and, consequently, altering the proliferation, differentiation or apoptosis of hemopoietic precursor cells. The p53 hypomethylation predisposes to critical mutations that enhance the transformation process of myelodysplasia to leukemia. The recognition of altered methylation of these genes in myelodysplasia may have prognostic implications and may lead to novel therapeutic modalities.

7.
Leuk Lymphoma ; 43(8): 1605-12, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12400603

RESUMO

According to the widely accepted myeloma staging system, the bulk of paraprotein is the main determinant of disease stage. However, myelomatous plasma cells differ considerably in their ability to synthesize and secrete monoclonal paraprotein. We determined plasma cell secreting potential (PCSP) as the amount of M-component, divided by the percentage of marrow plasmacytic infiltration, in 240 patients with myeloma, and correlated our results with chain isotype, plasma cell morphology, severity of bone disease, well-recognized prognostic factors, such as serum LDH, CRP, albumin and beta2-microglobulin, treatment response and overall survival. PCSP was higher in IgG than in other myeloma types, and was an almost constant parameter for each individual patient, in 134/166 cases. A > 10% decrease of PCSP in 26 patients was associated with disease aggressiveness and treatment failure. Patients with MGUS had significantly higher PCSP than those with myeloma of the same chain type. Higher PCSP was associated with stage I, absence of Bence-Jones proteinuria and indolent forms of disease with lower proliferating cell nuclear antigen (PCNA) positivity, serum LDH, alpha2-globulins, CRP and beta2-microglobulin and higher albumin levels. Conversely, patients with immature/plasmablastic morphology and those with severe bone disease had lower PCSP. Good responders to treatment had significantly higher PCSP than moderate and poor responders and PCSP was strongly correlated with overall survival in IgG and IgA myeloma. In conclusion, PCSP reflects the maturation status of myelomatous cells and therefore can be used as a prognostic factor, since patients with high secreting potential represent a lower malignancy group, in comparison to those with a low secreting potential.


Assuntos
Mieloma Múltiplo/metabolismo , Plasmócitos/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteína de Bence Jones/urina , Doenças Ósseas/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/mortalidade , Mieloma Múltiplo/patologia , Estadiamento de Neoplasias , Prognóstico , Antígeno Nuclear de Célula em Proliferação/análise
8.
Am J Hematol ; 71(1): 24-32, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12221670

RESUMO

Ticlopidine-induced aplastic anemia (TIAA) is considered very uncommon. We present two new cases, and we review 55 additional cases from the literature. The first case concerns a 70-year-old man who developed severe aplastic anemia 7 weeks after treatment with 500 mg of ticlopidine daily. The patient sustained a severe septic episode, was treated with antibiotics and GM-CSF, and recovered the 14(th) day after ticlopidine withdrawal. The second was an 82-year-old man receiving ticlopidine for 2 years when, during a febrile episode, he was found neutropenic with marrow aplasia. Ticlopidine withdrawal and treatment with antibiotics, transfusions, and G-CSF helped him to recover. When the data of the 57 patients are evaluated, a reversible direct cytotoxic effect of ticlopidine on the pluripotent/bipotent hematopoietic progenitor stem cell is proposed. It is estimated that the real incidence if TIAA is higher, and many cases, initially presented as agranulocytosis +/- thrombocytopenia, might be true aplastic anemias, not proven by marrow aspiration or trephine biopsy. There is no effective monitoring to prevent this side effect. Recombinant growth factors appear not to help in shortening the neutropenic period.


Assuntos
Anemia Aplástica/induzido quimicamente , Inibidores da Agregação Plaquetária/efeitos adversos , Ticlopidina/efeitos adversos , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Agranulocitose/induzido quimicamente , Anemia Aplástica/complicações , Anemia Aplástica/diagnóstico , Anemia Aplástica/epidemiologia , Antibacterianos , Transfusão de Sangue , Medula Óssea/patologia , Diabetes Mellitus Tipo 2/complicações , Erros de Diagnóstico , Quimioterapia Combinada/uso terapêutico , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Células-Tronco Hematopoéticas/efeitos dos fármacos , Humanos , Masculino , Doenças Vasculares Periféricas/complicações , Sepse/tratamento farmacológico , Sepse/etiologia , Distribuição por Sexo , Trombocitopenia/induzido quimicamente
10.
Eur J Intern Med ; 11(3): 161-164, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10854823

RESUMO

Background: The purpose of this study was to assess the effectiveness of alpha-IFN in adult beta-thalassemic patients with chronic hepatitis C. After a long-term follow-up, we describe the special pattern of biochemical and virological response of thalassemics. Methods: Thirty-two anti-HCV-positive adult thalassemic patients (19 female and 13 male, mean age 23.4+/-5.5 years) with biopsy-proven chronic hepatitis were treated with IFN alpha2beta at a dose of 3 MU thrice weekly for 6-12 months. The patients were followed up until 45-62 months after the end of treatment. Results: A sustained response was obtained in eight patients (25%). Only two of the sustained responders (25%) normalized ALT during the first 3 months of treatment. Both early and late biochemical responders cleared HCV-RNA after 6 months of treatment. Eight patients (25%) responded with ALT normalization within 2 months of treatment but relapsed soon after stopping IFN. Sixteen patients (50%) did not respond to IFN. Conclusion: The response rate in multitransfused thalassemic patients with chronic hepatitis C treated with IFN is similar to that in non-thalassemics. The special feature of thalassemics is that early biochemical response does not predict a sustained response; on the contrary, patients who normalize ALT after 6 months of IFN treatment usually do not relapse.

11.
Clin Hemorheol Microcirc ; 22(1): 35-43, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10711820

RESUMO

The rheological properties of human leukocytes (WBCs) have been studied using the micropipette aspiration and the filtration technique. Partial micropipette (i.d. 2.8-4.5 microm) aspiration of individual leukocytes under constant aspiration pressure of 8 mm H20 and measurement of the aspirated length as a function of time (creep experiments) according to the Evans model have been carried out and the apparent viscosity mu(app) was estimated. In the filtration experiments, using the Hemorheometer, the Index Rigidity of Leukocytes, ILR, was also estimated. The apparent viscosity mu(app) of normal PMN and MNC was significantly different p < 0.05), while the LYM and PMN had no statistical difference (p < 0.5). The leukocytes of the cell line HL-60 were more rigid than the normal PMN (p < 0.01), while the PMN from patients with type II diabetes mellitus were more rigid than the normal PMN (p < 0.005). The results of IRL showed similar differences among all of the leukocyte subpopulations. Comparison of these findings suggests a possible relationship between ILR and mu(app) which in this case is: ILR = 598 + 0.54 mu(app) (r = 0.986, p-value 0.0003).


Assuntos
Hemofiltração/normas , Leucócitos/classificação , Adulto , Idoso , Viscosidade Sanguínea , Tamanho Celular , Diabetes Mellitus Tipo 2/sangue , Células HL-60 , Hemofiltração/métodos , Humanos , Leucócitos/fisiologia , Linfócitos/fisiologia , Pessoa de Meia-Idade , Monócitos/fisiologia , Neutrófilos/fisiologia
12.
Mol Cell Endocrinol ; 160(1-2): 115-22, 2000 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-10715545

RESUMO

We studied whether programmed cell death (or apoptosis) is the predominant mechanism in radiation-induced cell damage to rat intestinal mucosa and investigated the mechanism of the protective effect of GH and IGF-I in the same model. Male albino Wistar rats were divided into four groups: controls, radiation, radiation plus GH and radiation plus IGF-I. Radiation was administered on the first day and on day 4. All animals were sacrificed and segments of the terminal ileum were stained with hematoxylin-eosin. Apoptosis of the epithelial cells was identified at the cellular level by the TUNEL stain and was distinguished from necrosis by the characteristic morphology of the cells (cytoplasmic shrinkage, marginal chromatin condensation and generation of nuclear apoptotic bodies). Apoptotic cells in the control animals were few and detected only at the tips of the villi while in the irradiated animals almost all the epithelial cells were apoptotic, distributed from the crypts to the tips of the villi and the mucosa showed severe epithelial atrophy and ulceration. The histologic picture of the mucosa in the GH and IGF-I treated animals was similar to normal controls and apoptotic cells were restricted only at the tips of the villi. DNA and RNA from the mucosa cells were isolated and analyzed by electrophoresis. DNA fragmentation and RNA 28s band ribonuclease cleavage was observed only in the irradiated animals. We have shown that abdominal radiation causes intestinal epithelial cell damage mainly through the induction of apoptosis and the treatment with GH and IGF-I inhibits apoptosis of the cells and preserves the mucosal integrity.


Assuntos
Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Hormônio do Crescimento Humano/farmacologia , Fator de Crescimento Insulin-Like I/farmacologia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/efeitos da radiação , Animais , Fragmentação do DNA/efeitos dos fármacos , Fragmentação do DNA/efeitos da radiação , Íleo/citologia , Íleo/efeitos dos fármacos , Íleo/efeitos da radiação , Marcação In Situ das Extremidades Cortadas , Mucosa Intestinal/citologia , Masculino , RNA/metabolismo , Ratos , Ratos Wistar
13.
Eur J Gastroenterol Hepatol ; 11(9): 1033-6, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10503842

RESUMO

AIM: The aim of this study was to assess the prevalence of diabetes mellitus in patients with hepatitis C virus (HCV) chronic hepatitis and secondary haemochromatosis as a consequence of beta-thalassaemia major. This group of patients was studied in order to reveal subtle effects of early stages of HCV infection on glucose metabolism, made more apparent by the coexistence of the diabetogenic effect of haemochromatosis. PATIENTS AND METHODS: The study included 108 beta-thalassaemic multitransfused patients, 55 females and 53 males, age 26.8+/-9 years. Sixty-four patients were seropositive for HCV by ELISA-3 (61/64 HCV-polymerase chain reaction-positive by Amplicor). In 51 of these, chronic hepatitis C was documented by liver biopsy, which also showed incomplete cirrhosis for eight and cirrhosis for four patients. Diabetes was diagnosed according to the criteria of the National Diabetes Data Group of the National Institutes of Health. RESULTS: (1) Patients with thalassaemia and HCV infection were diabetic more often than thalassaemic patients without HCV infection (45.3% versus 11.3%; P<0.001). This highly significant difference was also found when patients with definite cirrhosis or incomplete cirrhosis were excluded (41% versus 11.3%; P<0.01). (2) The high frequency of diabetes in thalassaemic patients with HCV chronic hepatitis is not related to body mass index or iron load, but it seems especially evident in patients over 25 years of age (50% of HCV-positive were diabetic versus 9.5% of HCV-negative; P<0.01). CONCLUSION: The frequency of diabetes in adult thalassaemic patients is significantly increased by HCV infection, even in the absence of cirrhosis. It is probable that the coexistence of haemochromatosis makes the effect of HCV infection on glucose metabolism clinically evident, even in the stage of chronic hepatitis.


Assuntos
Diabetes Mellitus/etiologia , Hepatite C Crônica/complicações , Talassemia beta/complicações , Adolescente , Adulto , Idoso , Diabetes Mellitus/epidemiologia , Feminino , Hepacivirus , Hepatite C Crônica/patologia , Humanos , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prevalência , Estudos Retrospectivos
14.
Eur Urol ; 21(1): 85-8, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1606990

RESUMO

Primary non-Hodgkin's lymphoma of the bladder is a rare entity and when found in such an unusual location is often difficult to distinguish from other vesical or extravesical neoplasms. Understanding of the pathobiological characteristics of this malignancy has been hampered not only because of its rarity but also by the previous confusion in its nomenclature. Factors that influence survival most strongly are the stage and the bulk of disease at presentation and the histologic classification of the tumor. We report a case of primary non-Hodgkin's lymphoma of the bladder presenting as a large pelvic mass which dramatically regressed with systemic chemotherapy with simultaneous restoration of the upper dilated urinary tracts. In addition, the incidence, clinical picture, staging procedures, histologic classification and treatment modalities of this disease are reviewed.


Assuntos
Linfoma não Hodgkin , Neoplasias da Bexiga Urinária , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Terapia Combinada , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Grécia/epidemiologia , Humanos , Linfoma não Hodgkin/diagnóstico , Linfoma não Hodgkin/epidemiologia , Linfoma não Hodgkin/terapia , Masculino , Prednisona/administração & dosagem , Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/epidemiologia , Neoplasias da Bexiga Urinária/terapia , Vincristina/administração & dosagem
15.
Eur J Haematol ; 47(4): 277-81, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1954986

RESUMO

We determined nine immune function parameters at diagnosis in patients with myelodysplastic syndromes (MDS) and correlated the results with the FAB classification and prognosis by univariate and multivariate analyses. Patients with refractory anaemia (RA) and refractory anaemia with ring sideroblasts (RAS) tended to have a higher CD4/CD8 ratio and a lower amount of gamma-globulins and soluble interleukin-2 receptors in serum in comparison to those suffering from the other three subgroups of MDS. FAB classification, neutrophil and CD8+ T-cell number had the best discriminatory capacity for predicting survival less than 1 year, and FAB classification, neutrophil number and serum TNF levels were predictors for conversion to acute leukaemia. The frequent occurrence of infections, on the other hand, could be better predicted by the absolute numbers of neutrophils and CD4+ cells and by the skin test score.


Assuntos
Linfócitos/imunologia , Síndromes Mielodisplásicas/imunologia , Idoso , Análise de Variância , Antígenos CD4/análise , Antígenos CD8/análise , Feminino , Seguimentos , Humanos , Células Matadoras Naturais/imunologia , Masculino , Análise Multivariada , Síndromes Mielodisplásicas/classificação , Síndromes Mielodisplásicas/diagnóstico , Síndromes Mielodisplásicas/terapia , Neutrófilos/fisiologia , Prognóstico , Testes Cutâneos , Subpopulações de Linfócitos T/imunologia
17.
Mol Endocrinol ; 3(11): 1845-51, 1989 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2481817

RESUMO

It has been shown previously that the rate of glucose transport in fibroblasts is accelerated by oncoproteins such as v-src, ras, and the transforming protein of feline sarcoma virus. This induction of glucose transport is associated with, and presumably caused by, induction of Hep-G2/rat brain glucose transporter gene expression. To determine the mechanism underlying the induction of glucose transporter gene expression by the v-src oncogene we studied cell lines that overexpress the normal counterpart of the v-src protein (c-src), or various mutants of the c-src protein. In these mutants, the tyrosines at positions 416, 527, or 519, or various combinations of these, have been replaced by phenylalanine by site directed mutagenesis, resulting in mutated c-src proteins that possess varying tyrosine kinase activity and transforming potential. Cells that overexpress the c-src protein show no changes in glucose transporter gene expression. However, when Tyr 527 in the COOH terminus of the c-src protein is replaced with Phe, the tyrosine kinase activity and transforming potential of the protein are increased and the protein acquires a potent ability to increase levels of glucose transporter mRNA and protein, as well as the rate of 2-deoxy-D-glucose uptake. This ability is abolished by the double mutation of Tyr to Phe in positions 416 and 527, which reduces the tyrosine kinase activity of the 527 single mutant. Thus, the ability of src proteins to induce expression of the glucose transport system is linked to the tyrosine kinase activity of the protein.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Proteínas de Transporte de Monossacarídeos/genética , Proteínas Tirosina Quinases/fisiologia , Proteínas Proto-Oncogênicas/fisiologia , Animais , Vírus do Sarcoma Aviário/genética , Linhagem Celular , Linhagem Celular Transformada , Desoxiglucose/farmacocinética , Fibroblastos/metabolismo , Regulação da Expressão Gênica , Camundongos , Proteínas de Transporte de Monossacarídeos/biossíntese , Mutação , Proteína Oncogênica pp60(v-src)/genética , Proteína Oncogênica pp60(v-src)/fisiologia , Fosforilação , Fosfotirosina , Processamento de Proteína Pós-Traducional , Proteínas Tirosina Quinases/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas pp60(c-src) , Proteínas Recombinantes de Fusão/fisiologia , Tirosina/análogos & derivados , Tirosina/fisiologia
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