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1.
J Exp Med ; 182(6): 1985-96, 1995 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-7500044

RESUMO

Resting autoreactive T cells are present in the circulation of normal individuals without pathologic consequences. In autoimmune animal models, stimulation of these self-reactive T cells in the presence of costimulatory molecules B7-1 results in T cell-mediated autoimmune disease, whereas B7-2 stimulation generates regulatory autoreactive T cells that abrogate disease severity. Thus, reactivation in the brain of myelin-autoreactive T cells by antigen with costimulatory molecules may be a critical event in the pathophysiology of multiple sclerosis (MS), a putative autoimmune disease of central nervous system (CNS) myelin. We investigated the expression of cytokines and costimulatory molecules in a panel of 41 histologically characterized CNS specimens from 15 MS and 10 control cases using semiquantitative reverse transcriptase-polymerase chain reaction and immunocytochemistry. In four cases, vascular CNS infarcts with inflammation were compared with MS plaques from the same brain. We observed increased expression of B7-1 and interleukin (IL) 12p40 in acute MS plaques, particularly from early disease cases but not in inflammatory infarcts. B7-1 staining was localized predominantly to the lymphocytes in perivenular inflammatory cuffs but not the parenchyma. In contrast, B7-2 was expressed predominantly on macrophages both in MS lesions of varied time duration and in inflammatory infarcts. These findings indicate that an early event in the initiation of MS involves upregulation of B7-1 and IL-12, resulting in conditions that maximally stimulate T cell activation and induction of T helper 1-type immune responses.


Assuntos
Antígenos CD/metabolismo , Antígeno B7-1/metabolismo , Encéfalo/imunologia , Interleucina-12/metabolismo , Glicoproteínas de Membrana/metabolismo , Esclerose Múltipla/imunologia , Adulto , Idoso , Antígeno B7-2 , Sequência de Bases , Encéfalo/patologia , Criança , Primers do DNA/química , Feminino , Expressão Gênica , Humanos , Técnicas Imunoenzimáticas , Imunofenotipagem , Linfócitos/imunologia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Esclerose Múltipla/patologia , RNA Mensageiro/genética
3.
Mult Scler J Exp Transl Clin ; 3(4): 2055217317745340, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29276624

RESUMO

BACKGROUND: Evolution of gadolinium-enhancing lesions into chronic black holes (CBH) may be reduced by interferon (IFN) therapy. OBJECTIVE: The objective of this paper is to assess the effect of IFN ß-1a and placebo on CBH evolution and disability in patients with relapsing-remitting multiple sclerosis (RRMS), as well as CBH evolution in patients with secondary progressive multiple sclerosis (SPMS). METHODS: A post hoc, exploratory analysis of patients with RRMS and SPMS with monthly MRI scans (months -1 to 9) from two separate placebo-controlled clinical trials of IFN ß-1a was conducted. RESULTS: In RRMS patients, the risk of ≥1 evolved CBH was lower for IFN ß-1a versus placebo (odds ratio 0.42; p = 0.024); volume of newly evolved CBH was numerically reduced. A numerically higher proportion of patients with ≥1 evolving CBH vs no evolving CBH had confirmed three-month disability progression (four-year rate 55.8% vs 43.1%, respectively). Proportion of lesions evolving into CBH (patient level: 34.7% vs 12.6%, p < 0.0001; lesion level: 28.8% vs 11.0%, p < 0.0001) and evolved CBH volume (median 33.5 mm3 (Quartile 1, 0.0; Quartile 3, 173.4) vs 0.0 mm3 (0.0; 52.4); p = 0.0008) was higher for SPMS than RRMS patients treated with IFN ß-1a. CONCLUSION: In RRMS, IFN ß-1a significantly decreased the proportion of new T1 Gd+ lesions evolving into CBH and the risk of developing a CBH. In patients with SPMS, more lesions develop to CBH, indicating reduced repair capacity, and the natural history of lesion development appears to be unaffected by IFN ß-1a treatment.

4.
Physiol Genomics ; 7(2): 97-104, 2001 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-11773596

RESUMO

This study creates a compendium of gene expression in normal human tissues suitable as a reference for defining basic organ systems biology. Using oligonucleotide microarrays, we analyze 59 samples representing 19 distinct tissue types. Of approximately 7,000 genes analyzed, 451 genes are expressed in all tissue types and designated as housekeeping genes. These genes display significant variation in expression levels among tissues and are sufficient for discerning tissue-specific expression signatures, indicative of fundamental differences in biochemical processes. In addition, subsets of tissue-selective genes are identified that define key biological processes characterizing each organ. This compendium highlights similarities and differences among organ systems and different individuals and also provides a publicly available resource (Human Gene Expression Index, the HuGE Index, http://www.hugeindex.org) for future studies of pathophysiology.


Assuntos
Biologia Computacional/normas , Bases de Dados Genéticas , Perfilação da Expressão Gênica/normas , Expressão Gênica , Especificidade de Órgãos/genética , Análise por Conglomerados , Feminino , Variação Genética , Humanos , Internet , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Valores de Referência
5.
Neurology ; 44(9): 1754-5, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7936310

RESUMO

We report a 74-year-old woman with opsoclonus, myoclonus, ataxia, and encephalopathy who had small-cell lung cancer and high titers of anti-Hu antibody in her serum. At autopsy, there were perivascular inflammatory infiltrates in the brainstem, putamen, and meninges overlying the orbital frontal cortex. Immunohistochemical studies showed the expression of the Hu antigens by the tumor and the presence of deposits of anti-Hu IgG in the patient's cortex, brainstem, and cerebellum, suggesting that anti-Hu immune response was related to the patient's clinical syndrome. This case of paraneoplastic opsoclonus, myoclonus, ataxia, and encephalopathy expands the spectrum of neurologic dysfunction associated with the anti-Hu antibody.


Assuntos
Anticorpos/sangue , Mioclonia/imunologia , Proteínas do Tecido Nervoso/imunologia , Transtornos da Motilidade Ocular/imunologia , Síndromes Paraneoplásicas/imunologia , Proteínas de Ligação a RNA/imunologia , Idoso , Encefalopatias/imunologia , Carcinoma de Células Pequenas/imunologia , Ataxia Cerebelar/imunologia , Proteínas ELAV , Feminino , Humanos , Neoplasias Pulmonares/imunologia
6.
Neurology ; 43(12): 2715-7, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8255488

RESUMO

Calcific brain embolization leading to stroke is rarely recognized. We report a case of spontaneous embolization to the right cerebral circulation from a severely regurgitant, calcified bicuspid valve. Bicuspid aortic valves constitute the most common congenital heart abnormality, and have a tendency to become stenosed, regurgitant, calcified, or infected. The presence of heavy calcification in a noninfected bicuspid valve may lead to dislodgement of calcific embolic material which is not necessarily heralded by acute valvular rupture. Accurate localization of the calcific embolus to the right supraclinoid internal carotid artery was provided by spiral CT imaging in this case.


Assuntos
Insuficiência da Valva Aórtica/complicações , Valva Aórtica/diagnóstico por imagem , Calcinose/etiologia , Artéria Carótida Interna , Embolia e Trombose Intracraniana/etiologia , Adulto , Insuficiência da Valva Aórtica/diagnóstico por imagem , Calcinose/diagnóstico , Calcinose/patologia , Artéria Carótida Interna/patologia , Ecocardiografia Transesofagiana , Humanos , Embolia e Trombose Intracraniana/diagnóstico , Embolia e Trombose Intracraniana/patologia , Masculino , Tomografia Computadorizada por Raios X
7.
Neurology ; 42(12): 2251-7, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1361034

RESUMO

We report the familial occurrence and apparent autosomal dominant inheritance of alternating hemiplegia of childhood. The proband, a 9-year-old boy, presented with developmental retardation, rare tonic-clonic seizures, and frequent episodes of flaccid alternating hemiplegia that had been presumed to represent postictal paralysis. The hemiplegia spells, which started in his first year, did not respond to multiple antiepileptics. Between attacks, there was choreoathetosis and dystonic posturing. Father, brother, paternal uncle, and paternal grandmother had similar histories of alternating hemiplegia. Investigations included negative CT, metabolic, and coagulation studies. EEG and SPECT 99mTc exametazime scanning failed to reveal any significant slowing or any major changes in cortical perfusion during hemiplegia as compared with nonhemiplegic periods. The karyotype revealed a balanced reciprocal translocation, 46,XY,t(3;9)(p26;q34) in the patient, in all the affected living relatives, and in one apparently unaffected sibling. The asymptomatic mother had a normal karyotype. Analysis of DNA markers was consistent with the karyotype results. Both affected siblings were treated with and responded to flunarizine therapy, with a greater than 70% decrease in attack frequency. Documented flunarizine trough serum concentrations were 28.9 ng/ml in the proband and 6.6 ng/ml in his brother.


Assuntos
Epilepsia/diagnóstico , Hemiplegia/genética , Adulto , Criança , Pré-Escolar , Diagnóstico Diferencial , Eletroencefalografia , Flunarizina/uso terapêutico , Genes Dominantes , Ligação Genética , Hemiplegia/diagnóstico , Hemiplegia/tratamento farmacológico , Humanos , Cariotipagem , Masculino , Linhagem , Polimorfismo de Fragmento de Restrição , Síndrome , Tomografia Computadorizada de Emissão de Fóton Único
8.
J Neuroimmunol ; 76(1-2): 132-8, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9184642

RESUMO

Human microglia constitute the primary residential antigen presenting cells (APCs) in the central nervous system (CNS) and have the capacity of activating myelin reactive T-cells. T-cell activation requires two signals: first is the interaction of the T-cell receptor with the MHC-antigen complex and, secondly, contact of the CD28/CTLA4 T-cell surface molecules with the B7 family of costimulatory molecules on the APCs. We have previously shown high expression of B7.1 in early multiple sclerosis (MS) plaques, suggesting that acute T-cell-mediated CNS inflammation may require local B7.1 upregulation. We have now examined the expression of B7.1 and B7.2 costimulatory molecules on resting ex-vivo human microglia isolated directly from biopsy specimens. We found constitutive expression of B7.2 but not B7.1 on resting microglia, suggesting that B7.2 expression may lead to downregulation of pro-inflammatory Th1 T-cell responses in the normal brain.


Assuntos
Autoimunidade , Antígeno B7-1/análise , Encéfalo/imunologia , Microglia/imunologia , Adolescente , Células Cultivadas , Pré-Escolar , Feminino , Humanos , Masculino
9.
Mol Cell Endocrinol ; 172(1-2): 13-20, 2001 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-11165035

RESUMO

Recent evidence indicates that corepressor protein with histone deacetylase (HDAC) activity mediates thyroid hormone receptor (TR) transcriptional repression. In order to examine the physiological relevance of HDAC in ligand-independent TR-mediated repression, we studied the effect of trichostatin A (TSA), a specific HDAC inhibitor, in transient transfection studies with natural reporters, and assessed the expression of TR-regulated endogenous genes. Luciferase-coupled DR4-, F2-, PAL- or GH-TREs and TRbeta1 expression vectors were cotransfected in CV-1 and GH(3) cells. We did not observe any effect of TSA on TR-induced basal repression in CV-1 cells. Instead, TSA was able to induce an increase in transcription without T(3) on all TREs tested in GH(3) cells. This increase was >7-fold on F2-, >4-fold on DR4-, and 3-fold on GH-TREs. The cotransfection of a TRbeta1 mutant that exhibits decreased affinity with N-CoR (AHT) reduced the TSA effect in GH(3) cells, demonstrating a primary role for TR/N-CoR/Sin3/HDAC complex. Next, we examined the effects of TSA on endogenous GH mRNA production in GH(3) cells by Northern blot analysis. We observed an increase of 50-70% of GH mRNA in cells treated with TSA in hypothyroid medium, and an increase of GH mRNA in T(3)-treated cells after TSA treatment. Our results show that TSA can increase the expression of endogenous genes that are susceptible to TR regulation. These results support an active role of HDAC in transcriptional repression by ligand-independent TR.


Assuntos
Histona Desacetilases/genética , Receptores dos Hormônios Tireóideos/genética , Proteínas Repressoras/farmacologia , Animais , Linhagem Celular , Inibidores Enzimáticos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Genes Reporter/efeitos dos fármacos , Hormônio do Crescimento/genética , Inibidores de Histona Desacetilases , Histona Desacetilases/fisiologia , Ácidos Hidroxâmicos/farmacologia , Rim/citologia , Especificidade de Órgãos , Hipófise/citologia , Ratos , Elementos de Resposta/genética , Transcrição Gênica/efeitos dos fármacos , Transfecção
10.
Int J Oncol ; 19(4): 773-7, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11562754

RESUMO

Enzymes which affect histone acetylation status have been shown to play an important role in determining transcriptional activity in chromatin through conformational modification of its structure. Since the timely presence of such enzymes may be of critical importance, our experiments were designed to determine whether the level of expression of HDAC1 is cell cycle dependent and/or affected by a high cell density. Our results show that in mouse fibroblasts the expression of mHDAC1 is neither affected by cell cycle phases nor by cell density. In contrast, the expression of several hHDACs including hHDAC1 were affected in a cell density dependent fashion in the human prostate adenocarcinoma cell line PC3, paralleling our previously published findings in the hepatocellular carcinoma derived cell line Hep3B. Differential recruitment of HDAC mRNAs suggests that these enzymes may play unique roles in different cell types and under different environmental conditions (i.e., exposure to various cell densities and cell-cell contacts). Our study has implications for the proposed use of HDAC inhibitors in the treatment of human malignancy, highlighting issues of drug action selectivity in tissues and potential secondary effects.


Assuntos
Contagem de Células , Ciclo Celular/fisiologia , Fibroblastos/citologia , Histona Desacetilases/metabolismo , Células Tumorais Cultivadas/patologia , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Animais , Northern Blotting , Butiratos/farmacologia , Divisão Celular , Sondas de DNA , Fibroblastos/metabolismo , Histona Desacetilase 1 , Histona Desacetilases/genética , Humanos , Masculino , Camundongos , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Ribonuclease Pancreático/metabolismo , Células Tumorais Cultivadas/metabolismo
11.
Am J Trop Med Hyg ; 52(2): 155-8, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7872443

RESUMO

Tropical spastic paraparesis (TSP) is a retroviral disease characterized predominantly by a chronic myelopathy and progressive leg weakness. Four patients from the northern coast of Columbia with chronic spastic paraparesis and serum positivity for antibodies to human T cell lymphotropic virus type 1 by enzyme-linked immunosorbent assay and Western blot are reported. All patients had mixed ethnic origins (white, black, and amerindian). This is the first report of TSP on the Caribbean coast of Colombia. This study extends the geographic boundaries of TSP in the Caribbean basin.


Assuntos
Paraparesia Espástica Tropical , Adulto , Idoso , Estudos de Casos e Controles , Colômbia , Feminino , Anticorpos Anti-HTLV-I/sangue , Humanos , Masculino , Exame Neurológico
12.
Gene Expr ; 11(1): 13-21, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12691522

RESUMO

Within the context of the chromatin environment histone deacetylases are important transcriptional regulators. Three classes of human histone deacetylases have currently been identified on the basis of their similarity to yeast proteins. The class I enzymes contain four members: HDACs 1-3 and HDAC8. Of these, HDAC3 is known to generate transcript variants with altered amino-terminal regions. Here we describe the identification of a novel splice variant of HDAC3, in which exon 3 is alternatively spliced from the messenger RNA transcript. We show that this human HDAC3 splice transcript is upregulated by treatments with histone deacetylase inhibitors. We also demonstrate evidence of splicing events in murine HDAC3 as a response to various signals, including switching between splice transcript isoforms following treatments with kinase inhibitors or by osmotic shock. In contrast, such switching events were not observed in human cells. These results indicate that differential pathways in mouse and human may control the regulation of HDAC3, and that splice variants may play important roles in responding to exogenous stimuli that act via signal transduction pathways.


Assuntos
Processamento Alternativo/genética , Células Eucarióticas/enzimologia , Genes Reguladores/genética , Histona Desacetilases/genética , Transdução de Sinais/genética , Animais , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/metabolismo , Inibidores Enzimáticos/farmacologia , Éxons/genética , Líquido Extracelular/metabolismo , Histona Desacetilases/metabolismo , Humanos , Neoplasias Renais/genética , Neoplasias Renais/metabolismo , Camundongos , Pressão Osmótica , Isoformas de Proteínas/genética , RNA Mensageiro/genética , Especificidade da Espécie , Células Tumorais Cultivadas
13.
Pediatr Neurol ; 9(6): 491-3, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-7605561

RESUMO

The diagnosis of pre-eruptive varicella cerebellitis is usually based on a history of exposure and thus depends on a subjective clinical assessment. The confirmation of the diagnosis has traditionally depended on the development of skin manifestations of varicella and on varicella-zoster antibody seroconversion. Confirming the diagnosis of pre-eruptive cerebellar ataxia or encephalitis early in the course of a viral infection may save the patient unnecessary tests, procedures, or attempts at therapeutic intervention. A patient is reported in whom, after clinically suspecting a diagnosis of pre-eruptive varicella cerebellitis, the diagnosis was confirmed by performing polymerase chain reaction analysis of varicella-zoster virus DNA in peripheral blood leukocytes and cerebrospinal fluid. The patient developed skin manifestations of varicella 5 days after the onset of neurologic symptoms and 15 days after known exposure. In some patients with preeruptive varicella cerebellitis, polymerase chain reaction may be extremely useful for rapid confirmation of the diagnosis.


Assuntos
Ataxia Cerebelar/diagnóstico , Varicela/diagnóstico , Encefalite Viral/diagnóstico , Reação em Cadeia da Polimerase , Ataxia Cerebelar/virologia , Varicela/virologia , Criança , DNA Viral/genética , DNA Viral/isolamento & purificação , Encefalite Viral/virologia , Feminino , Herpesvirus Humano 3/genética , Humanos
14.
Pediatr Neurol ; 4(4): 207-12, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3072006

RESUMO

A child with infantile sialic acid storage disease is reported. Ultrasonography demonstrated fetal ascites. At birth, the infant appeared hydropic and presented with numerous dysmorphic features, including sparse white hair, coarse facies, hypertelorism, epicanthal folds, anteverted nostrils, and a long philtrum. In addition, he had visceromegaly, bilateral inguinal hernias, and a slight gibbus deformity. Lymphocytes were vacuolated and bone marrow contained large numbers of foam cells. There were generalized vacuolations of both reticuloendothelial and parenchymal cells in the examined tissues. Neuropathologic studies revealed wide-spread neuronal storage, myelin loss, axonal spheroids, and gliosis. Neurons, endothelial cells, and Kupffer cells stained with wheat germ agglutinin indicated an accumulation of sialic acid. Free sialic acid was significantly increased in urine and serum, as well as in liver, heart, and brain tissues. The alpha-neuraminidase activity was normal. It is assumed that the basic defect of infantile sialic acid storage disease lies in impaired transport of sialic acid across the lysosomal membrane.


Assuntos
Nefropatias/complicações , Doenças Metabólicas/complicações , Ácidos Siálicos/metabolismo , Encéfalo/metabolismo , Encéfalo/patologia , Humanos , Lactente , Nefropatias/patologia , Fígado/metabolismo , Fígado/patologia , Doenças Metabólicas/patologia , Miocárdio/metabolismo , Miocárdio/patologia
15.
Mult Scler Relat Disord ; 2(1): 45-56, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25877454

RESUMO

BACKGROUND: In clinical studies, treatment with subcutaneous interferon beta-1a (IFNß-1a) has been shown to reduce relapse rates and slow the progression of physical disability in patients with relapsing forms of multiple sclerosis (MS). A formulation of subcutaneous IFNß-1a has been developed that is free of fetal bovine serum and human serum albumin. OBJECTIVE: To evaluate (a) the impact on quality of life (QoL) and treatment satisfaction of transitioning from the original formulation of subcutaneous IFNß-1a to the serum-free formulation in patients with relapsing forms of MS; and (b) the impact of dose titration versus non-titration during the transition on tolerability and patterns of analgesic use. QoL was measured by the Multiple Sclerosis Treatment Concerns Questionnaire Global Side Effects (GSE) score. METHODS: Patients who had received the original formulation of IFNß-1a subcutaneously for ≥24 weeks were randomized to receive the serum-free formulation of IFNß-1a 44µg subcutaneously three times weekly for 12 weeks, with or without a dose titration over a 4-week period. After week 12, patients continued to receive serum-free subcutaneous IFNß-1a during a safety extension phase until they completed between 84 and 112 weeks of treatment. The primary endpoint was the percentage change from baseline to week 12 in GSE score in all patients. RESULTS: A total of 232 patients were randomized (titrated n=113; non-titrated n=119). The mean percent change (improvement) from baseline to week 12 in the GSE score was 5.0% (p<0.001 for mean change in GSE score from baseline); this change was similar between titrated and non-titrated patients and met criteria for non-inferiority to the original formulation. Adverse event (AE) incidence and use of analgesics for the treatment of flu-like symptoms (FLS) were less common in the titrated group. Few patients (<2%) discontinued due to AEs during weeks 0 to 12. CONCLUSION: Patients with relapsing forms of MS who transitioned from original-formulation subcutaneous IFNß-1a to serum-free subcutaneous IFNß-1a had overall improved QoL scores at 12 weeks of treatment. Titration during the transition resulted in a lower requirement for analgesic treatment of FLS and fewer AEs.

16.
Mult Scler Relat Disord ; 1(2): 87-94, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25876936

RESUMO

BACKGROUND: For patients with multiple sclerosis (MS), electronic autoinjectors may improve convenience and reduce discomfort associated with chronic injections. OBJECTIVE: To assess ease of use, patient satisfaction, and functional reliability of an investigational electronic autoinjector for self-injection of subcutaneous interferon beta-1a (IFNß-1a). METHODS: This prospective, multicenter, open-label, single-arm, 12-week, Phase IIIb study enrolled patients aged 18-65 years with relapsing MS receiving IFNß-1a 44µg subcutaneously 3 times weekly for ≥12 weeks before enrollment. Thereafter, patients continued their regimen using an electronic autoinjector. The primary endpoint was the proportion of patients rating the autoinjector 'easy to use' or 'very easy to use' on a User Trial Questionnaire at week 12. Secondary endpoints included patient responses to questions regarding device reliability, patient satisfaction, and convenience. RESULTS: Of 103 patients enrolled, 88 completed the study. The primary objective was met, with most patients (78%) indicating the device was 'easy to use' or 'very easy to use' at week 12 (worst-case imputation). In an analysis of secondary endpoints, over 60% of patients responded favorably to each of the User Trial questions regarding device ease-of-use and their satisfaction with the device. Overall convenience was judged the most important benefit of the device. Adverse events reported were consistent with the known safety profile of IFNß-1a, with injection site reactions the most frequently reported. CONCLUSION: These data show that patients found the electronic autoinjector for delivery of subcutaneous IFNß-1a reliable and easy to use, suggesting the device may help patients with relapsing MS to administer self-injections.

19.
Biochem Biophys Res Commun ; 247(3): 833-7, 1998 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-9647779

RESUMO

The reversible acetylation of histones by histone deacetylases (HDACs) and acetyltransferases (HATs) plays a fundamental role in gene transcription. We previously showed that HDAC mRNA is upregulated in immune cells upon PHA-induced activation. Little is known, however, about the differential regulation of HDAC mRNAs by the HDAC inhibitors Trichostatin A (TSA) and butyrate, agents known to block proliferation and induce apoptosis. We report that apoptosis-inducing concentrations of TSA and butyrate upregulate the expression of HDAC mRNAs in a differential manner and act synergistically with PHA to induce HDAC expression, suggesting the presence of independent HDAC regulatory mechanisms. Moreover, we show that HDAC inhibitor-induced apoptosis is associated with early abrogation of gamma-IFN production by Th1 lymphocytes and with p53 mRNA downregulation. Our findings highlight the dynamic interplay of cell cycle-, activation- and apoptosis-related proteins in association with time-dependent expression of HDACs and are suggestive of different specific roles for these enzymes.


Assuntos
Butiratos/farmacologia , Linfócitos T CD4-Positivos/enzimologia , Regulação da Expressão Gênica/genética , Histona Desacetilases/genética , Ácidos Hidroxâmicos/farmacologia , RNA Mensageiro/metabolismo , Proteínas de Saccharomyces cerevisiae , Acetiltransferases/fisiologia , Apoptose/efeitos dos fármacos , Ácido Butírico , Ciclo Celular/fisiologia , Divisão Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Citometria de Fluxo , Genes p53/genética , Histona Acetiltransferases , Humanos , Interferon gama/metabolismo , Isoenzimas/metabolismo , Fito-Hemaglutininas/farmacologia , Timidina/metabolismo , Regulação para Cima/efeitos dos fármacos
20.
Headache ; 33(5): 257-8, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8320102

RESUMO

Four cases of idiopathic stabbing headache subjectively perceived as lasting several seconds are reported. The classification of the International Headache Society suggests that these headaches typically last "a fraction of a second". The perception of such brief pains may be difficult to quantitate and, therefore, the duration of the headache should not be used as a strict diagnostic criteria.


Assuntos
Cefaleia/fisiopatologia , Adulto , Feminino , Humanos , Masculino , Fatores de Tempo
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