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1.
Rev. colomb. reumatol ; 28(2): 111-117, abr.-jun. 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1357256

RESUMO

ABSTRACT Background: MicroRNAs (miRNAs) are non-coding RNAs that regulate gene expression post-transcriptionally. Accumulating evidence indicates that the miR-30 family takes part in the development of multiple tissues and organs, and is a potential contributor to various dis eases, including autoimmune disorders such as systemic lupus erythematosus (SLE). The aim of this study was to evaluate the expression of miR-30e-5p, a member of the miR-30 fam ily, and investigate its potential relationship to clinical characteristics and possible disease activity in an Egyptian SLE cohort. Methods: Serum samples from 40 SLE patients and 37 age and gender matched healthy sub jects were tested for miR-30e-5p expression level using the Taqman quantitative reverse transcription-polymerase chain reaction. Analysis was performed using the 2 - AACT method. Results: The mean age of the patients was 28.7 ± 7.9 years, with a mean disease duration of 6.4 ±5.3 years. The median fold change in serum miR-30e-5p among our SLE cohort was significantly higher 1.748 (0.223-20.485) compared to the control group 0.877 (0.058-3.522) (P = 0.02). Receiver operating characteristic curve analysis revealed that miR-30e-5p expres sion level can discriminate SLE patients from controls at a cut-off value >1.06 with the area under the curve (AUC) = 0.676 (95% CI: 0.559-0.794, P = 0.02), with 64.3% sensitivity and 61.5% specificity. There was no correlation between any of the demographic features, clinical manifestations (apart from serositis, P = 0.013) or disease activity and miR-30e-5p levels. Conclusion: Our study demonstrated elevated miR-30e-5p expression levels in serum sam ples of SLE patients. Apart from serositis, it was not associated with any other disease characteristics.


RESUMEN Antecedentes: Los microARN (miRNA) son ARN no codificantes que regulan la expresión de los genes después de la transcripción. Las pruebas acumuladas indican que la familia de miR-30 participa en el desarrollo de múltiples tejidos y órganos, y es un posible contribuyente a diversas enfermedades, incluidos los trastornos autoinmunes como el lupus eritematoso sistémico (LES). El objetivo de este estudio fue evaluar la expresión del miR-30e-5p, un miembro de la familia miR-30, e investigar su posible relación con las características clínicas y la posible actividad de la enfermedad en una cohorte egipcia de LES. Métodos: Se analizaron muestras de suero de 40 pacientes con LES y 37 sujetos sanos de edad y sexo similares para determinar el nivel de expresión de miR-30e-5p, utilizando la reacción en cadena de la polimerasa de transcripción inversa cuantitativa Taqman. El análisis se llevó a cabo empleando el método 2-AACT. Los resultados: La edad media de los pacientes fue de 28,7 ± 7,9 años, mientras que la duración media de la enfermedad fue de 6,4 ± 5,3 años. La mediana del cambio de pliegue del suero miR-30e-5p entre nuestra cohorte de LES fue significativamente mayor, 1,748 (0,223-20,485), en comparación con el grupo de control, 0,877 (0,058-3,522) (p = 0,02). El análisis de la curva característica de funcionamiento del receptor reveló que el nivel de expresión del miR-30e-5p puede discriminar a los pacientes con LES de los controles en un valor de corte > 1,06, con el área bajo la curva (AUC) = 0,676 (IC del 95%: 0,559-0,794; p = 0,02), una sensibilidad del 64,3% y una especificidad del 61,5%. No hubo asociación entre ninguna de las características demográficas, manifestaciones clínicas (aparte de la serositis, p = 0,013) o actividad de la enfermedad y los niveles de miR-30e-5p. Conclusión: Nuestro estudio demostró niveles elevados de expresión de miR-30e-5p en mues tras de suero de pacientes con LES. Aparte de la serositis, no se asoció con ninguna otra característica de la enfermedad.


Assuntos
Humanos , Feminino , Adulto , Reação em Cadeia da Polimerase , Doenças da Pele e do Tecido Conjuntivo , Ácidos Nucleicos, Nucleotídeos e Nucleosídeos , Processos Patológicos , Serosite , Condições Patológicas, Sinais e Sintomas , Elementos Antissenso (Genética) , RNA Antissenso , Doenças do Tecido Conjuntivo , MicroRNAs , Lúpus Eritematoso Sistêmico
2.
Salud pública Méx ; 56(6): 631-637, nov.-dic. 2014.
Artigo em Espanhol | LILACS | ID: lil-733342

RESUMO

Objetivo. Analizar la percepción que el prestador de servicios de salud y el adulto mayor (AM) tienen sobre el maltrato al AM en los servicios públicos de salud, en ciudades seleccionadas de México. Material y métodos. De 2009 a 2012 se realizó un estudio con diseño cualitativo y estrategia de triangulación de fuentes de datos; se efectuaron entrevistas semiestructuradas a 13 prestadores y a 12 ancianos para recuperar su experiencia en el tema. El análisis utilizó procedimientos de la Teoría Fundamentada. Resultados. El maltrato contra el AM es una práctica naturalizada por el personal y por el anciano, la cual se manifiesta de formas diversas. Conclusiones. La institucionalización, profesionalización histórica y falta de conciencia sobre las necesidades de los AM demandan cambios de planeación, organización y supervisión del Sistema de Salud. El personal requiere intervenciones de formación, capacitación y cambio de actitudes/comportamiento, para otorgar atención integral, digna, humana y de respeto a los Derechos Humanos de los AM.


Objective. To analyze the health care providers (HCP) and elderly patients' perceptions about abuse of the elderly by health personnel of public health services, in selected cities in Mexico. Materials and methods. A qualitative study and a strategy of data triangulation were performed during 2009 and 2012; 13 HCPs and 12 elders were interviewed, in order to obtain their experience regarding elder abuse. Grounded Theory proceedings were used for the analysis. Results. Elder abuse is a naturalized practice, from HCP and elderly people's point of view; these perceptions are showed in different ways. Conclusion. Institutionalization, historical professionalization and lack of consciousness about needs of the elderly (sociocultural and economic), require changes in planning, organization and monitoring process in the Health System; training and educational interventions on staff and exchange attitudes and behavior are necessary in order to offer a health care that is comprehensive, decent, human and with respect for the human rights.


Assuntos
Animais , Feminino , Humanos , Camundongos , Antimetabólitos Antineoplásicos/farmacologia , Ciclinas/metabolismo , Inibidores Enzimáticos/metabolismo , Fenilacetatos/farmacologia , Elementos Antissenso (Genética) , Neoplasias da Mama , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Divisão Celular/efeitos dos fármacos , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Ciclinas/genética , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/enzimologia , Regulação Neoplásica da Expressão Gênica/fisiologia , Camundongos Knockout , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , RNA Mensageiro/metabolismo , Proteína do Retinoblastoma/metabolismo , Transdução de Sinais/fisiologia , Células Tumorais Cultivadas/citologia , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/enzimologia , Regulação para Cima/efeitos dos fármacos
3.
Exp Parasitol ; 135(3): 532-40, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24012862

RESUMO

Programmed cell death (PCD) is induced in Entamoeba histolytica by a variety of stimuli in vitro and in vivo. In mammals, intracellular acidification serves as a global switch for inactivating cellular processes and initiates molecular mechanisms implicated in the destruction of the genome. In contrast, intracellular alkalinization produced by P-glycoprotein overexpression in multidrug-resistant cells has been related to apoptosis resistance. Our previous studies showed that overexpression of E. histolytica P-glycoprotein (PGP) altered chloride-dependent currents and triggered trophozoite swelling, the reverse process of cell shrinkage produced during PCD. Here we showed that antisense inhibition of PGP expression produced a synchronous death of trophozoites and the enhancement of biochemical and morphological characteristics of PCD induced by G418. The nucleus was contracted, and the nuclear membrane was disrupted. Moreover, chromatin was extensively fragmented. Ca(2+) concentration was increased, while the intracellular pH (ipH) was acidified. In contrast, PGP overexpression prevented intracellular acidification and circumvented the apoptotic effect of G418.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Amebicidas/farmacologia , Apoptose/fisiologia , Entamoeba histolytica/metabolismo , Gentamicinas/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/efeitos dos fármacos , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Elementos Antissenso (Genética)/fisiologia , Apoptose/efeitos dos fármacos , Entamoeba histolytica/efeitos dos fármacos , Entamoeba histolytica/ultraestrutura , Expressão Gênica , Concentração de Íons de Hidrogênio , Plasmídeos , Transfecção , Trofozoítos/metabolismo
4.
Methods Enzymol ; 457: 395-404, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19426880

RESUMO

Uncoupling protein 2 (UCP2) is a member of the uncoupling protein family. It is expressed in the inner mitochondrial membrane and plays a role in the control of free radical production, oxidative damage, insulin secretion, and fatty-acid peroxide exportation. Although UCP2 expression occurs in several tissues, some of its most remarkable functions are exerted in organs of difficult experimental access, such as the central nervous system, particularly the hypothalamus and the pancreatic islets. In addition, due to its low levels of expression in the mitochondrial membrane, studying UCP2 expression and function depends on specific- and well-established methods. This chapter describes methods for directly assessing UCP2 expression and function in different tissues. Purified mitochondria preparations are used for enhancing the capacity of detection of UCP2 protein or for evaluating the role of UCP2 in mitochondria respiration. Exposure of experimental animals to cold environment leads to increased UCP2 expression, while reduction of its expression can be achieved directly by targeting its mRNA with antisense oligonucleotides, or indirectly by targeting PGC-1alpha expression with antisense oligonucleotides.


Assuntos
Regulação da Expressão Gênica , Canais Iônicos/genética , Canais Iônicos/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Animais , Elementos Antissenso (Genética) , Temperatura Baixa , Hipotálamo/metabolismo , Immunoblotting , Canais Iônicos/isolamento & purificação , Ilhotas Pancreáticas/metabolismo , Masculino , Camundongos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Proteínas Mitocondriais/isolamento & purificação , Oxigênio/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Reação em Cadeia da Polimerase , Proteínas de Ligação a RNA/genética , Ratos , Ratos Wistar , Fatores de Transcrição/genética , Proteína Desacopladora 2
5.
Eur J Endocrinol ; 156(1): 65-74, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17218727

RESUMO

OBJECTIVE: It is believed that the variable effectiveness of somatostatin analogs in post-surgical management of somatotropinomas and non-functioning pituitary adenomas (NFPA) may be due in part to variable expression of somatostatin receptor isoforms (SSTR1-5), within and between pituitary tumor types. DESIGN AND METHODS: Quantitative real-time RT-PCR was used to compare absolute mRNA copy numbers for all five SSTR isoforms in 23 somatotropinomas and 19 NFPA. RESULTS: Somatostatin receptor subtype 5 mRNA was present at the highest level in somatotropinomas, followed by SSTR2>SSTR3>>SSTR1>>>SSTR4. In contrast, SSTR3 mRNA was present at the highest level in NFPA, followed by SSTR2, while SSTR1, SSTR4, and SSTR5 transcripts were only detectable in select tumors. Among somatotropinomas, a positive correlation was found between SSTR2 mRNA levels and the percent decrease of GH (%GH) after 3 and 6 months of therapy with octreotide long acting repeatable (LAR) (r=0.51 and r=0.66; P=0.05 and P=0.008). Also the percent decrease of IGF-I (%IGF-I) after 3 months of octreotide LAR was negatively correlated with SSTR5 and %IGF-I after 6 months of octreotide LAR was positively correlated with SSTR2. CONCLUSIONS: The present report is a large series examining SSTR mRNA levels in somatotropinomas and NFPA. These initial findings suggest that detailed knowledge of the SSTR mRNA expression profile in somatotropinomas can help to predict the hormonal response to therapy with LAR. Also, it appears that SSTR3 in NFPA may be a potential target for SSTR3 preferential or universal ligands such as pasireotide.


Assuntos
Adenoma/metabolismo , Hormônio do Crescimento Humano/metabolismo , Neoplasias Hipofisárias/metabolismo , Receptores de Somatostatina/genética , Acromegalia/etiologia , Adenoma/cirurgia , Adulto , Elementos Antissenso (Genética) , Primers do DNA , Feminino , Seguimentos , Dosagem de Genes , Expressão Gênica , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Octreotida/uso terapêutico , Neoplasias Hipofisárias/cirurgia , RNA Mensageiro/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa
6.
Artigo em Inglês | LILACS | ID: lil-339344

RESUMO

The 15-mer oligonucleotide sequence was synthesized, aminolinked (sense and antisense phosphodiester) and conjugated with S-Acetyl-NHS-MAG3 by a N-hydroxy-succinimide derivative. The purified MAG3-DNA was radiolabeled with 99mTc by transchelation from sodium tartrate and free 99mTc was separated by gel filtration. The radiolabeled antisense and sense probes were injected intravenously in mammary tumor-bearing KM mice(1×106 cells,6 days post inoculation).Biodistribution was studied and the mice were imaged.Essentially complete conjugation was achieved by reverse-phase Sep-Pak C18 chromatography analysis.The MAG3-DNA was labeled with 99mTc at room temperature and neutral pH, with a mean labeling efficiency of 80.11 percent (s.d=2.96 percent , N=4). After labeling, the stability of the DNA in saline or serum was retained as determined by reverse-phase Sep-Pak C18 chromatography analysis, except a shift at 30 min in serum incubation which might suggest a short time serum protein binding. The labeled antisense DNA still remained the ability to hybridize with its complementary DNA. The pharmacodynamics of 99mTc labeled c-myc probes (antisense and sense) in mammary tumor-bearing KM mice did not change with the time postinjection. The highest accumulation of label was in the liver first, with the kidney and small bowel next. The injected activity localized in the lesion as early as 30min and reached a saturation value at 4hr. The accumulation of radioactivity in the tumor was lower at all time points in animals receiving the blocking oligonucleotides or sense probes. All images obtained with 99mTc-MAG3-c-myc antisense probes showed specific accumulation of radioactivity at the site of tumor. Radiolabel rapidly accumulates at the site of tumor and remains associated with the site even though circulation levels of radioactivity have greatly diminished. The tumor was readily evident since 45min and reached the highest tumor-to-muscle ratio at 4hr. The quite encouraging result was obtained at 20hr to 22hr when the background activity was diminished sufficiently. Positive imaging was not obtained in case of control group (in which non-conjugated, non-labeled antisense oligonucleotides were administered 2hr before the radiolabeled antisense probes were injected) and of sense group. Conclusion The 99mTc labeled antisense probe may provide a sensible and specific tool for noninvasive imaging of c-myc oncogene mRNA for a variety of malignant tumors at an earlier stage


Assuntos
Animais , Camundongos , Neoplasias Mamárias Experimentais , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Radiometria , Genes myc , Tecnécio , Elementos Antissenso (Genética)/análise
7.
Steroids ; 67(6): 477-82, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11960624

RESUMO

Studies with different cell types have shown that modulation of various of the fast as well as long-term responses to 1,25(OH)(2)D(3) depends on the activation of tyrosine kinase pathways. Recent investigations of our laboratory have demonstrated that 1,25(OH)(2)D(3) rapidly stimulates in muscle cells tyrosine phosphorylation of PLC-gamma and the growth-related proteins MAPK and c-myc. We have now obtained evidence using antisense technology indicating that VDR-dependent activation of Src mediates the fast stimulation of tyrosine phosphorylation of c-myc elicited by the hormone. This non-genomic action of 1,25(OH)(2)D(3) requires tyrosine phosphorylation of the VDR. Immunoprecipitation under native conditions coupled to Western blot analysis revealed 1,25(OH)(2)D(3)-dependent formation of complexes between Src and the VDR and c-myc. However, the activation of MAPK by the hormone was only partially mediated by the VDR and required in addition increased PKC and intracellular Ca(2+). Following its phosphorylation, MAPK translocates into the nucleus where it regulates c-myc transcription. Altogether these results indicate that tyrosine phosphorylation plays a role in the stimulation of muscle cell growth by 1,25(OH)(2)D(3). Data were also obtained involving tyrosine kinases and the VDR in hormone regulation of the Ca(2+) messenger system by mediating the stimulation of store-operated calcium (SOC; TRP) channels. Congruent with this action, 1,25(OH)(2)D(3) induces a rapid translocation of the VDR to the plasma cell membrane which can be blocked by tyrosine kinase inhibitors. Of mechanistic relevance, an association between the VDR and TRP proteins with the participation of the scaffold protein INAD was shown.


Assuntos
Músculo Esquelético/efeitos dos fármacos , Receptores de Calcitriol/metabolismo , Esteroide Hidroxilases/farmacologia , Animais , Elementos Antissenso (Genética)/análise , Proteína Tirosina Quinase CSK , Cálcio/metabolismo , Núcleo Celular/metabolismo , Células Cultivadas , Embrião de Galinha , Ativação Enzimática , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Músculo Esquelético/citologia , Músculo Esquelético/metabolismo , Fosforilação/efeitos dos fármacos , Proteína Quinase C/metabolismo , Transporte Proteico , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Fosfolipases Tipo C/metabolismo , Tirosina/metabolismo , Quinases da Família src
8.
Nat Biotechnol ; 19(3): 231-4, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11231555

RESUMO

Peptide nucleic acids (PNAs) may be a potent tool for gene function studies in medically important parasitic organisms, especially those that have not before been accessible to molecular genetic knockout approaches. One such organism is Entamoeba histolytica, the causative agent of amebiasis, which infects about 500 million people and is the cause of clinical disease in over 40 million each year, mainly in the tropical and subtropical world. We used PNA antisense oligomers to inhibit expression of an episomally expressed gene (neomycin phosphorotransferase, NPT) and a chromosomal gene (EhErd2, a homolog of Erd2, a marker of the Golgi system in eukaryotic cells) in axenically cultured trophozoites of E. histolytica. Measurement of NPT enzyme activity and EhErd2 protein levels, as well as measurement of cellular proliferation, revealed specific decreases in expression of the target genes, and concomitant inhibition of cell growth, in trophozoites treated with micromolar concentrations of unmodified antisense PNA oligomers.


Assuntos
Elementos Antissenso (Genética)/farmacologia , Regulação para Baixo/efeitos dos fármacos , Entamoeba histolytica/efeitos dos fármacos , Canamicina Quinase/metabolismo , Ácidos Nucleicos Peptídicos/farmacologia , Animais , Elementos Antissenso (Genética)/genética , Biomarcadores/análise , Divisão Celular/efeitos dos fármacos , Entamoeba histolytica/enzimologia , Entamoeba histolytica/genética , Entamoeba histolytica/crescimento & desenvolvimento , Gentamicinas/farmacologia , Complexo de Golgi/efeitos dos fármacos , Complexo de Golgi/metabolismo , Canamicina Quinase/biossíntese , Canamicina Quinase/genética , Proteínas de Membrana/biossíntese , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Microscopia de Fluorescência , Neomicina/metabolismo , Ácidos Nucleicos Peptídicos/genética , Permeabilidade , Transfecção
9.
Neuroreport ; 10(15): 3131-6, 1999 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-10574548

RESUMO

To study the specific contribution of the D3 dopamine receptor in the generation of locomotor activity, total or partially dopamine-depleted rats were pretreated with an antisense oligodeoxynucleotide for the D3 receptor (D3R-as) and locomotor activity induced by apomorphine was measured. A 35.7% increase in locomotor activity was seen in the totally dopamine-depleted rats pretreated with the D3R-as, whereas the same antisense, caused a significantly greater increase in the locomotor response (95%) in the partially dopamine-depleted rats compared with control groups (pretreated with a control oligodeoxynucleotide or vehicle). In situ autoradiography for D3 receptors showed a 27% fall in the density of D3 receptors in the islands of Calleja compared with control animals. Our results seem to confirm that D3 receptors exert an inhibitory effect on locomotor activity, through the stimulation of both pre- and postsynaptic components.


Assuntos
Elementos Antissenso (Genética)/farmacologia , Locomoção/efeitos dos fármacos , Receptores de Dopamina D2/metabolismo , Inibidores da Captação Adrenérgica/farmacologia , Animais , Apomorfina/farmacologia , Autorradiografia , Sítios de Ligação , Agonistas de Dopamina/farmacologia , Regulação para Baixo/fisiologia , Feminino , Ínsulas Olfatórias/metabolismo , Ínsulas Olfatórias/fisiologia , Locomoção/fisiologia , Oligonucleotídeos/farmacologia , Ratos , Ratos Wistar , Receptores de Dopamina D3 , Reserpina/farmacologia , Fatores de Tempo
10.
Braz J Med Biol Res ; 32(7): 867-75, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10454746

RESUMO

A large number of DNA sequences corresponding to human and animal transcripts have been filed in data banks, as cDNAs or ESTs (expression sequence tags). However, the actual function of their corresponding gene products is still largely unknown. Several of these genes may play a role in regulation of important biological processes such as cell division, differentiation, malignant transformation and oncogenesis. Elucidation of gene function is based on 2 main approaches, namely, overexpression and expression interference, which respectively mimick or suppress a given phenotype. The currently available tools and experimental approaches to gene functional analysis and the most recent advances in mass cDNA screening by functional analysis are discussed.


Assuntos
Elementos Antissenso (Genética) , Expressão Gênica , RNA Catalítico , Transgenes , Animais , DNA Recombinante , Humanos
11.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;32(7): 867-75, July 1999.
Artigo em Inglês | LILACS | ID: lil-234893

RESUMO

A large number of DNA sequences corresponding to human and animal transcripts have been filed in data banks, as cDNAs or ESTs (expression sequence tags). However, the actual function of their corresponding gene products is still largely unknown. Several of these genes may play a role in regulation of important biological processes such as cell division, differentiation, malignant transformation and oncogenesis. Elucidation of gene function is based on 2 main approaches, namely, overexpression and expression interference, which respectively mimick or suppress a given phenotype. The currently available tools and experimental approaches to gene functional analysis and the most recent advances in mass cDNA screening by functional analysis are discussed


Assuntos
Animais , Humanos , Elementos Antissenso (Genética) , Expressão Gênica , RNA Catalítico , Transgenes , DNA Recombinante
12.
Brain Res Mol Brain Res ; 69(1): 1-9, 1999 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-10350632

RESUMO

Repeated amphetamine (AMPH) administration results in behavioral sensitization. To investigate the participation of the opioid system in this phenomenon, we examined the effects of acute and repeated AMPH administration on mu-opioid receptor (MOR) mRNA levels in the nucleus accumbens (NAc) and striatum (STR) of rats, by quantitative non-radioactive in situ hybridization. Five injections of d-AMPH (1.5 mg kg-1, i.p., once every other day), resulted in a sensitization response profile and a significant down-regulation of MOR mRNA levels in the NAc shell, whereas no change was observed in MOR mRNA levels in the NAc core compared to the saline controls. Conversely, MOR mRNA levels were up-regulated in the rostral STR of AMPH-sensitized rats compared to saline controls. No changes in MOR mRNA levels were observed after acute AMPH treatment in any of the brain regions studied. These results suggest that the opioid system participates in the neurobiological underpinnings of behavioral sensitization and that opioid receptor (OR) expression in the STR and NAc shell and core is differentially modulated by repeated AMPH exposure.


Assuntos
Anfetamina/farmacologia , Comportamento Animal/efeitos dos fármacos , Estimulantes do Sistema Nervoso Central/farmacologia , Núcleo Accumbens/química , Receptores Opioides mu/genética , Animais , Elementos Antissenso (Genética) , Química Encefálica/efeitos dos fármacos , Química Encefálica/genética , Corpo Estriado/química , Corpo Estriado/fisiologia , Regulação da Expressão Gênica/efeitos dos fármacos , Hibridização In Situ , Locomoção/efeitos dos fármacos , Masculino , Núcleo Accumbens/fisiologia , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley
13.
Cell Death Differ ; 6(12): 1209-15, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10637437

RESUMO

In mammalian cells, terminal differentiation is mutually exclusive with proliferation. However, resistance to differentiation-inducing therapy requires alternative strategies to control poorly responsive tumors. We now show that retroviral transfer of the antisense cyclin D1 gene to differentiation-refractory K1735 melanoma leads to loss of in vivo tumorigenicity, shortened replicative ability, induction of the tumor suppressor p53 protein and of the cdk-inhibitor p21WAF1, increased beta-galactosidase pH 6.0 activity, and elevation in the ratio of superoxide dismutases to peroxidases, all properties associated with replicative senescence. However, pigmentation and tyrosinase expression, characteristic of differentiated melanocytic cells or apoptosis-associated PARP cleavage, were not increased by antisense cyclin D1 transduction. Our data suggests that targetting cyclin D1 inhibition suppresses melanoma tumorigenicity by promoting a cytostatic differentiation-independent pathway, mediated by activation of p53 and anti-oxidant functions.


Assuntos
Proteínas de Ciclo Celular , Ciclina D1/genética , Ciclinas/biossíntese , Melanoma Experimental/genética , Superóxido Dismutase/biossíntese , Proteína Supressora de Tumor p53/biossíntese , Proteínas Supressoras de Tumor , Animais , Antioxidantes/metabolismo , Elementos Antissenso (Genética) , Apoptose , Catalase/metabolismo , Diferenciação Celular , Ciclina A/metabolismo , Inibidor de Quinase Dependente de Ciclina p21 , Inibidor de Quinase Dependente de Ciclina p27 , Ciclinas/genética , Regulação Neoplásica da Expressão Gênica , Técnicas de Transferência de Genes , Glutationa Peroxidase/metabolismo , Camundongos , Camundongos Endogâmicos C3H , Proteínas Associadas aos Microtúbulos/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Ligação Proteica , Proteína do Retinoblastoma/metabolismo
14.
J Neurosci ; 18(23): 9858-69, 1998 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-9822744

RESUMO

Cultures of cerebellar macroneurons were used to study the pattern of expression, subcellular localization, and function of the neuronal cdk5 activator p35 during laminin-enhanced axonal growth. The results obtained indicate that laminin, an extracellular matrix molecule capable of selectively stimulating axonal extension and promoting MAP1B phosphorylation at a proline-directed protein kinase epitope, selectively stimulates p35 expression, increases its association with the subcortical cytoskeleton, and accelerates its redistribution to the axonal growth cones. Besides, suppression of p35, but not of a highly related isoform designated as p39, by antisense oligonucleotide treatment selectively reduces cdk5 activity, laminin-enhanced axonal elongation, and MAP1b phosphorylation. Taken collectively, the present results suggest that cdk5/p35 may serve as an important regulatory linker between environmental signals (e.g., laminin) and constituents of the intracellular machinery (e.g., MAP1B) involved in axonal elongation.


Assuntos
Axônios/fisiologia , Quinases Ciclina-Dependentes , Laminina/genética , Proteínas do Tecido Nervoso/metabolismo , Neurônios/enzimologia , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Anticorpos , Elementos Antissenso (Genética) , Axônios/química , Células Cultivadas , Cerebelo/citologia , Quinase 5 Dependente de Ciclina , Epitopos/fisiologia , Imunofluorescência , Regulação Enzimológica da Expressão Gênica/fisiologia , Laminina/análise , Laminina/imunologia , Proteínas Associadas aos Microtúbulos/metabolismo , Neurônios/citologia , Neurônios/ultraestrutura , Fosforilação , RNA Mensageiro/análise , Coelhos
15.
J Cell Biol ; 143(2): 443-55, 1998 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-9786954

RESUMO

In this study we have examined the cellular functions of ERM proteins in developing neurons. The results obtained indicate that there is a high degree of spatial and temporal correlation between the expression and subcellular localization of radixin and moesin with the morphological development of neuritic growth cones. More importantly, we show that double suppression of radixin and moesin, but not of ezrin-radixin or ezrin-moesin, results in reduction of growth cone size, disappearance of radial striations, retraction of the growth cone lamellipodial veil, and disorganization of actin filaments that invade the central region of growth cones where they colocalize with microtubules. Neuritic tips from radixin-moesin suppressed neurons displayed high filopodial protrusive activity; however, its rate of advance is 8-10 times slower than the one of growth cones from control neurons. Radixin-moesin suppressed neurons have short neurites and failed to develop an axon-like neurite, a phenomenon that appears to be directly linked with the alterations in growth cone structure and motility. Taken collectively, our data suggest that by regulating key aspects of growth cone development and maintenance, radixin and moesin modulate neurite formation and the development of neuronal polarity.


Assuntos
Proteínas Sanguíneas/genética , Proteínas do Citoesqueleto , Cones de Crescimento/fisiologia , Proteínas de Membrana/genética , Proteínas dos Microfilamentos , Proteínas/genética , Células Piramidais/citologia , Actinas/metabolismo , Animais , Elementos Antissenso (Genética) , Proteínas Sanguíneas/metabolismo , Polaridade Celular/fisiologia , Células Cultivadas , Citoesqueleto/fisiologia , Expressão Gênica/fisiologia , Cones de Crescimento/química , Hipocampo/citologia , Proteínas de Membrana/metabolismo , Neuritos/química , Neuritos/fisiologia , Proteínas/metabolismo , Células Piramidais/química , Células Piramidais/ultraestrutura , Ratos , Frações Subcelulares/química , Tionucleotídeos
16.
Acta Haematol ; 91(1): 7-9, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-8171942

RESUMO

Genomic DNA from two Brazilian hemoglobin (Hb) Lepore heterozygotes of Italian ancestry have been studied in order to identify the Hb Lepore type and to sequence the breakpoint region. The two genes were sequenced after PCR amplification and had the delta globin sequence up to exon 2 codon 68 while the first specific base for the beta globin gene was at codon 86 of the second exon; between the two ends, they had 51 base pairs in common with the delta and beta globin genes. These data indicate that the mutation was of the Hb Lepore Baltimore type. The Lepore chromosome haplotype was different from that previously described in members of a Spanish family with Hb Lepore Baltimore. These data suggest that independent mutations have given rise to Hb Lepore Baltimore in different regions of the world.


Assuntos
DNA/sangue , Hemoglobinas Anormais/análise , Anemia/sangue , Anemia/etnologia , Anemia/genética , Elementos Antissenso (Genética)/sangue , Elementos Antissenso (Genética)/genética , Brasil/epidemiologia , Criança , Códon/sangue , Códon/genética , DNA/genética , Eritrócitos Anormais , Feminino , Haplótipos , Hemoglobinas Anormais/genética , Humanos , Itália/etnologia , Dados de Sequência Molecular , Reação em Cadeia da Polimerase
17.
J Pediatr ; 123(4): 509-18, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8410501

RESUMO

McCune-Albright syndrome (MCAS) is a sporadic disease classically including polyostotic fibrous dysplasia, café au lait spots, sexual precocity, and other hyperfunctional endocrinopathies. An activating missense mutation in the gene for the alpha subunit of GS, the G protein that stimulates cyclic adenosine monophosphate formation, has been reported to be present in these patients. The mutation is found in variable abundance in different affected endocrine and nonendocrine tissues, consistent with the mosaic distribution of abnormal cells generated by a somatic cell mutation early in embryogenesis. We describe three patients with MCAS who had profound endocrine and nonendocrine disease and who died in childhood. Two of the patients were severely ill neonates whose complex symptoms did not immediately suggest MCAS. A mutation of residue Arg201 of GS alpha was found in affected tissues from all three children. A review of the literature and unpublished case histories emphasizes the existence of other patients with severe and unusual clinical manifestations. We conclude that the manifestations of MCAS are more extensive than is generally appreciated, and may include hepatobiliary disease, cardiac disease, other nonendocrine abnormalities, and sudden or premature death.


Assuntos
Arginina/genética , Displasia Fibrosa Poliostótica/genética , Proteínas de Ligação ao GTP/genética , Adolescente , Elementos Antissenso (Genética) , AMP Cíclico/genética , Morte Súbita/epidemiologia , Doenças do Sistema Endócrino/genética , Feminino , Displasia Fibrosa Poliostótica/complicações , Humanos , Recém-Nascido , Masculino , Mosaicismo , Mutação , Reação em Cadeia da Polimerase , Fatores de Risco
18.
Blood ; 81(2): 462-7, 1993 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-8380725

RESUMO

In industrialized populations, Hodgkin's disease (HD) has an initial peak in young adulthood, whereas in economically developing populations the initial peak occurs in childhood. This pattern resembles that of infection with poliovirus and suggests an infectious cofactor in the etiology. Serologic studies have linked Epstein-Barr virus (EBV) to young adult and adult HD, and viral nucleic acids and antigens have been detected in a subset of Hodgkin's tumor specimens. To investigate the association of childhood HD with EBV we studied tumor specimens from 11 children treated in Honduras and 25 children treated in the United States using in situ hybridization and antigen detection techniques. Among the patients from Honduras, tumor specimens from all cases were EBV positive. Among the patients from the United States, tumor specimens from six of seven patients with mixed cellularity histology, 2 of 15 with nodular sclerosis histology, and neither of two patients with lymphocyte-predominant histologies were EBV positive. These findings support the hypothesis that EBV contributes to the pathogenesis of HD in children, particularly in mixed cellularity HD, and raises the possibility that there are important geographic, racial, or ethnic factors in the EBV association with HD.


Assuntos
Herpesvirus Humano 4/isolamento & purificação , Doença de Hodgkin/microbiologia , Adolescente , Elementos Antissenso (Genética) , Criança , Feminino , Herpesvirus Humano 4/genética , Doença de Hodgkin/classificação , Doença de Hodgkin/patologia , Honduras , Humanos , Hibridização In Situ , Masculino , Grupos Raciais , Estados Unidos
19.
Am J Hum Genet ; 50(6): 1252-8, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1350885

RESUMO

The lysosomal removal of the sulfate moiety from sulfatide requires the action of two proteins, arylsulfatase A and sphingolipid activator protein-1 (SAP-1). Recently, patients have been identified who have a variant form of metachromatic leukodystrophy which is characterized by mutations in the gene coding for SAP-1, which is also called "prosaposin." All of the mutations characterized in these patients result in (a) deficient mature SAP-1, as determined by immunoblotting after SDS-PAGE of tissue and cell extracts, and (b) decreased ability of cultured skin fibroblasts to metabolize endocytosed [14C]-sulfatide. We now report the insertion of the full-length prosaposin cDNA into the Moloney murine leukemia virus-derived retroviral vector, pLJ, and the infection of cultured skin fibroblasts from a newly diagnosed and molecularly characterized patient with SAP-1 deficiency. The cultured cells infected with the prosaposin cDNA construct now show both production of normal levels of mature SAP-1 and completely normal metabolism of endocytosed [14C]-sulfatide. These studies demonstrate that the virally transferred prosaposin cDNA is processed normally and is localized within lysosomes, where it is needed for interaction between sulfatide and arylsulfatase A. In addition, normal as well as mutant sequences can now be found by allele-specific oligonucleotide hybridization of PCR-amplified genomic DNA by using exonic sequences as primers.


Assuntos
Glicoproteínas/deficiência , Glicoproteínas/genética , Precursores de Proteínas/genética , Pele/metabolismo , Sulfoglicoesfingolipídeos/metabolismo , Transfecção , Elementos Antissenso (Genética) , Sequência de Bases , Células Cultivadas , Cerebrosídeo Sulfatase/metabolismo , Criança , Fibroblastos/enzimologia , Fibroblastos/metabolismo , Vetores Genéticos , Glicoproteínas/metabolismo , Humanos , Cinética , Leucodistrofia Metacromática/genética , Leucodistrofia Metacromática/metabolismo , Dados de Sequência Molecular , Mutação , Oligodesoxirribonucleotídeos , Plasmídeos , Reação em Cadeia da Polimerase , Precursores de Proteínas/metabolismo , Retroviridae/genética , Saposinas , Pele/enzimologia , Proteínas Ativadoras de Esfingolipídeos , Ácidos Esteáricos/metabolismo
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