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1.
Mol Cell Biol ; 27(14): 5147-60, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17515611

RESUMO

Tumor necrosis factor alpha (TNF-alpha) is a potent cytokine which regulates inflammation via the induction of adhesion molecules and chemokine expression. Its expression is known to be regulated in a complex manner with transcription, message turnover, message splicing, translation, and protein cleavage from the cell surface all being independently regulated. This study examined both cell lines and primary cells to understand the developmental regulation of epigenetic changes at the TNF-alpha locus. We demonstrate that epigenetic modifications of the TNF-alpha locus occur both developmentally and in response to acute stimulation and, importantly, that they actively regulate expression. DNA demethylates early in development, beginning with the hematopoietic stem cell. The TNF-alpha locus migrates from heterochromatin to euchromatin in a progressive fashion, reaching euchromatin slightly later in differentiation. Finally, histone modifications characteristic of a transcriptionally competent gene occur with myeloid differentiation and progress with differentiation. Additional histone modifications characteristic of active gene expression are acquired with stimulation. In each case, manipulation of these epigenetic variables altered the ability of the cell to express TNF-alpha. These studies demonstrate the importance of epigenetic regulation in the control of TNF-alpha expression. These findings may have relevance for inflammatory disorders in which TNF-alpha is overproduced.


Assuntos
Epigênese Genética , Fator de Necrose Tumoral alfa/genética , Acetilação/efeitos dos fármacos , Adenosina/análogos & derivados , Adenosina/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Metilação de DNA/efeitos dos fármacos , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Eucromatina/metabolismo , Histonas/metabolismo , Humanos , Hibridização in Situ Fluorescente , Camundongos , Modelos Genéticos , Transporte Proteico/efeitos dos fármacos , Sulfitos , Tionucleosídeos/farmacologia
2.
Rheumatology (Oxford) ; 45(2): 178-81, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16249245

RESUMO

OBJECTIVES: Patients with chronic granulomatous disease and carrier mothers of patients with chronic granulomatous disease are predisposed to developing various forms of lupus. This disorder is a neutrophil defect in intracellular killing. Abnormal apoptosis has been described. We hypothesized that abnormal apoptosis occurring in neutrophils of patients made them more immunogenic. METHODS: Human patients with chronic granulomatous disease were examined for abnormalities of neutrophil apoptosis by flow cytometry. To model the effect of abnormal apoptosis, a murine model was used. Apoptotic cells from either wild type or mice with chronic granulomatous disease were injected into either wild type or chronic granulomatous disease mice and autoantibodies were determined by ELISA. RESULTS: Our studies found that human and murine neutrophils carrying the gp91 form of chronic granulomatous disease had impaired exposure of phosphatidyl serine on the surface. Other markers of apoptosis were largely normal. Injection of apoptotic neutrophils from gp91 knockout mice into gp91 knockout mice led to the development of characteristic autoantibodies of lupus. CONCLUSIONS: Humans with chronic granulomatous disease may be at an increased risk of developing lupus due to abnormal apoptosis and abnormal clearance of apoptotic cells.


Assuntos
Apoptose , Autoanticorpos/biossíntese , Doença Granulomatosa Crônica/complicações , Lúpus Eritematoso Sistêmico/etiologia , Animais , Modelos Animais de Doenças , Doença Granulomatosa Crônica/imunologia , Doença Granulomatosa Crônica/patologia , Humanos , Lúpus Eritematoso Sistêmico/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neutrófilos/patologia , Receptores Imunológicos/genética
3.
J Chemother ; 11(5): 402-6, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10632388

RESUMO

Thirty patients with pretreated advanced breast cancer were enrolled in a study aimed to establish the maximum tolerated dose and to evaluate the efficacy of oral idarubicin (12 mg/m2/day for 3 days every 4 weeks) with tegafur and levo-folinate (200 mg/m2/day and 50 mg/day, respectively, for a minimum of 6 days, increasing the dose and duration according to a modified Fibonacci scheme). The maximum tolerated doses identified were 200 mg/m2 days 1-30 for tegafur and 50 mg days 1-30 for levo-folinate. We obtained 2 partial remissions (7%) and 12 stable disease (45%) in 27 objectively evaluable patients. The main toxicity was gastrointestinal, with no hematologic toxicity. Median time to progression was 4 months (range 2-14), median survival was 10 months (3-30). A median number of 4 cycles (1-13) was administered. The results seem to support the use of this combination in elderly and pretreated patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Administração Oral , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/patologia , Humanos , Idarubicina/administração & dosagem , Idarubicina/efeitos adversos , Leucovorina/administração & dosagem , Leucovorina/efeitos adversos , Pessoa de Meia-Idade , Tegafur/administração & dosagem , Tegafur/efeitos adversos
4.
Recenti Prog Med ; 83(12): 701-6, 1992 Dec.
Artigo em Italiano | MEDLINE | ID: mdl-1494710

RESUMO

Paget's disease is a bone disorder characterized by high rates of bone remodelling. We have evaluated the efficacy of the new drug, ipriflavone, which has a double effect on the inhibition of bone reabsorption and on the activation of bone neodeposition. We studied 20 patients with active Paget's disease: 10 have been treated with 600 mg/die and 10 with 1200 mg/die of ipriflavone, for six months. In pharmacological wash-out, we have measured alkaline phosphatase, plasmatic BGP, the urinary hydroxyproline/creatinine ratio and the urinary calcium (Nordin Test). These valuations have been repeated after three and six months from the beginning of the administration of the drug. We have verified a propitious and speedy effect on pain, independent of dosage, and efficacy of treatment in function of bone turn-over parameter changes, by using no parametric statistical tests. In all subjects favourable effects have been found after three months treatment with 1200 mg/die. These have shown a greater efficacy than the lower dosage. After six months treatment we have not found significant differences as regards the efficacy of both dosages. These results may suggest to start therapy with higher initial doses and to carry-on with lower supporting doses. It's necessary to investigate further confirmation regarding the consolidation and perseverance of obtained favourable results, even after interruption of the treatment.


Assuntos
Isoflavonas/administração & dosagem , Osteíte Deformante/tratamento farmacológico , Idoso , Remodelação Óssea/efeitos dos fármacos , Relação Dose-Resposta a Droga , Avaliação de Medicamentos , Humanos , Masculino , Pessoa de Meia-Idade , Osteíte Deformante/sangue , Osteíte Deformante/fisiopatologia , Fatores de Tempo
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