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1.
Mol Pharm ; 11(10): 3443-51, 2014 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-25189995

RESUMO

The M-type phospholipase A2 receptor (PLA2R1) is a member of the C-type lectin superfamily and can internalize secreted phospholipase A2 (sPLA2) via endocytosis in non-cancer cells. sPLA2 itself was recently shown to be overexpressed in prostate tumors and to be a possible mediator of metastasis; however, little is known about the expression of PLA2R1 or its function in prostate cancers. Thus, we examined PLA2R1 expression in primary prostate cells (PCS-440-010) and human prostate cancer cells (LNCaP, DU-145, and PC-3), and we determined the effect of PLA2R1 knockdown on cytotoxicity induced by free or liposome-encapsulated chemotherapeutics. Immunoblot analysis demonstrated that the expression of PLA2R1 was higher in prostate cancer cells compared to that in primary prostate cells. Knockdown of PLA2R1 expression in PC-3 cells using shRNA increased cell proliferation and did not affect the toxicity of cisplatin, doxorubicin (Dox), and docetaxel. In contrast, PLA2R1 knockdown increased the in vitro toxicity of Dox encapsulated in sPLA2 responsive liposomes (SPRL) and correlated with increased Dox and SPRL uptake. Knockdown of PLA2R1 also increased the expression of Group IIA and X sPLA2. These data show the novel findings that PLA2R1 is expressed in prostate cancer cells, that PLA2R1 expression alters cell proliferation, and that PLA2R1 modulates the behavior of liposome-based nanoparticles. Furthermore, these studies suggest that PLA2R1 may represent a novel molecular target for controlling tumor growth or modulating delivery of lipid-based nanomedicines.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Lipossomos/administração & dosagem , Neoplasias da Próstata/enzimologia , Receptores da Fosfolipase A2/metabolismo , Western Blotting , Linhagem Celular Tumoral , Humanos , Masculino , Nanopartículas/química , Receptores da Fosfolipase A2/genética , Células Tumorais Cultivadas
2.
Epidemiol Infect ; 141(2): 251-9, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22370185

RESUMO

Shiga toxin-producing Escherichia coli (STEC) have led to outbreaks worldwide and are considered emerging pathogens. Infections by STEC in humans have been reported after consumption of mainly beef, but also deer. This study investigated the occurrence of STEC in deer in Germany. The virulence genes eae, e-hlyA and saa, the stx subtypes, pulsed-field gel electrophoresis (PFGE) patterns and serovars were studied. In total, 120 samples of 60 animals were screened by real-time polymerase chain reaction (PCR). The PCR results showed a high detection rate of stx genes (83%). Mainly faecal samples, but also some lymphatic tissue samples, tested stx-positive. All isolates carried stx2, were eae-negative and carried e-hlyA in 38% and saa in 9% of samples. Serovars (O88:[H8], O174:[H8], O146:H28) associated with human diseases were also identified. In some animals, isolates from lymphatic tissue and faecal samples showed undistinguishable PFGE patterns. The examined deer were shown to be relevant reservoirs of STEC with subtype stx2b predominating.


Assuntos
Cervos/microbiologia , Infecções por Escherichia coli/veterinária , Fezes/microbiologia , Tecido Linfoide/microbiologia , Toxinas Shiga/genética , Escherichia coli Shiga Toxigênica/isolamento & purificação , Animais , Reservatórios de Doenças/veterinária , Eletroforese em Gel de Campo Pulsado , Alemanha , Reação em Cadeia da Polimerase em Tempo Real , Sorotipagem , Escherichia coli Shiga Toxigênica/classificação , Escherichia coli Shiga Toxigênica/genética , Escherichia coli Shiga Toxigênica/patogenicidade , Virulência/genética
4.
Rheumatology (Oxford) ; 47(10): 1489-92, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18703528

RESUMO

OBJECTIVE: Antibody subclasses reflect specific immunological processes and may be indicative of the underlying pathological pattern in an autoimmune disease like RA. We therefore quantified anti-cyclic citrullinated peptides (CCP) and anti- citrullinated vimentin (MCV) IgG subclass titres in RA patients and compared them with the respective titres of antibodies directed against the varicella zoster virus (VZV) and to total serum titres. METHODS: Sera of 77 patients fulfilling the ACR criteria for RA were collected. An IgG subclass-specific ELISA system was then established and combined with commercially available MCV, CCP and VZV pre-coated microtitre plates. RESULTS: Even though IgG1 is the predominant subclass among antibodies against CCP and MCV in RA patients, IgG4 is second with respect to titres and frequencies. This increase in IgG4 among RA-specific antibodies is independent of disease duration and does not reflect a general skewing of the immune response in these patients as overall serum titres and antibodies directed against VZV show a normal distribution of IgG1, IgG2, IgG3 and IgG4. CONCLUSION: Elevated IgG4 titres are specific for auto-antibodies against citrullinated antigens in RA and are indicative of a Th2-biased environment during the generation of auto-reactive plasma cells. We discuss here an indirect role for IgG4 auto-antibodies in hindering the elimination of auto-reactive B and plasma cells and thus driving the autoimmune process.


Assuntos
Artrite Reumatoide/imunologia , Autoanticorpos/sangue , Imunoglobulina G/sangue , Peptídeos Cíclicos/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/sangue , Estudos de Coortes , Ensaio de Imunoadsorção Enzimática/métodos , Herpesvirus Humano 3/imunologia , Humanos , Pessoa de Meia-Idade , Vimentina/imunologia
5.
Mol Cell Biol ; 19(5): 3383-94, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10207062

RESUMO

Some members of nuclear hormone receptors, such as the thyroid hormone receptor (TR), silence gene expression in the absence of the hormone. Corepressors, which bind to the receptor's silencing domain, are involved in this repression. Hormone binding leads to dissociation of corepressors and binding of coactivators, which in turn mediate gene activation. Here, we describe the characteristics of Alien, a novel corepressor. Alien interacts with TR only in the absence of hormone. Addition of thyroid hormone leads to dissociation of Alien from the receptor, as shown by the yeast two-hybrid system, glutathione S-transferase pull-down, and coimmunoprecipitation experiments. Reporter assays indicate that Alien increases receptor-mediated silencing and that it harbors an autonomous silencing function. Immune staining shows that Alien is localized in the cell nucleus. Alien is a highly conserved protein showing 90% identity between human and Drosophila. Drosophila Alien shows similar activities in that it interacts in a hormone-sensitive manner with TR and harbors an autonomous silencing function. Specific interaction of Alien is seen with Drosophila nuclear hormone receptors, such as the ecdysone receptor and Seven-up, the Drosophila homologue of COUP-TF1, but not with retinoic acid receptor, RXR/USP, DHR 3, DHR 38, DHR 78, or DHR 96. These properties, taken together, show that Alien has the characteristics of a corepressor. Thus, Alien represents a member of a novel class of corepressors specific for selected members of the nuclear hormone receptor superfamily.


Assuntos
Proteínas de Insetos/genética , Proteínas , Receptores dos Hormônios Tireóideos/genética , Proteínas Repressoras/genética , Sequência de Aminoácidos , Animais , Complexo do Signalossomo COP9 , Linhagem Celular , Núcleo Celular/genética , Proteínas de Ligação a DNA/genética , Drosophila , Imunofluorescência , Genes Reporter , Humanos , Proteínas de Insetos/química , Dados de Sequência Molecular , Mutação , Receptores de Glucocorticoides/metabolismo , Receptores do Ácido Retinoico/metabolismo , Receptores dos Hormônios Tireóideos/metabolismo , Receptores X de Retinoides , Fatores de Transcrição/metabolismo
6.
J Mol Biol ; 197(4): 723-8, 1987 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-2448477

RESUMO

The algorithm of Smith & Waterman for identification of maximally similar subsequences is extended to allow identification of all non-intersecting similar subsequences with similarity score at or above some preset level. The resulting alignments are found in order of score, with the highest scoring alignment first. In the case of single gaps or multiple gaps weighted linear with gap length, the algorithm is extremely efficient, taking very little time beyond that of the initial calculation of the matrix. The algorithm is applied to comparisons of tRNA-rRNA sequences from Escherichia coli. A statistical analysis is important for proper evaluation of the results, which differ substantially from the results of an earlier analysis of the same sequences by Bloch and colleagues.


Assuntos
Algoritmos , RNA Bacteriano , RNA Ribossômico , RNA de Transferência , Sequência de Bases , Escherichia coli/genética , Dados de Sequência Molecular , RNA Ribossômico 16S , RNA de Transferência de Alanina
7.
J Mol Biol ; 186(1): 117-28, 1985 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-3908689

RESUMO

The basic nature of the sequence features that define a promoter sequence for Escherichia coli RNA polymerase have been established by a variety of biochemical and genetic methods. We have developed rigorous analytical methods for finding unknown patterns that occur imperfectly in a set of several sequences, and have used them to examine a set of bacterial promoters. The algorithm easily discovers the "consensus" sequences for the -10 and -35 regions, which are essentially identical to the results of previous analyses, but requires no prior assumptions about the common patterns. By explicitly specifying the nature of the search for consensus sequences, we give a rigorous definition to this concept that should be widely applicable. We also have provided estimates for the statistical significance of common patterns discovered in sets of sequences. In addition to providing a rigorous basis for defining known consensus regions, we have found additional features in these promoters that may have functional significance. These added features were located on either side of the -35 region. The pattern 5', or upstream, from the -35 region was found using the standard alphabet (A, G, C and T), but the pattern between the -10 and the -35 regions was detectable only in a sub-alphabet. Recent results relating DNA sequence to helix conformation suggest that the former (upstream) pattern may have a functional significance. Possible roles in promoter function are discussed in this light, and an observation of altered promoter function involving the upstream region is reported that appears to support the suggestion of function in at least one case.


Assuntos
DNA Bacteriano/genética , Reconhecimento Automatizado de Padrão , Regiões Promotoras Genéticas , Sequência de Bases , Escherichia coli/genética , Métodos , Homologia de Sequência do Ácido Nucleico , Transcrição Gênica
8.
Arch Gen Psychiatry ; 53(6): 523-9, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8639035

RESUMO

BACKGROUND: This study investigated biochemical and family variables and predictors of recidivism among forensic psychiatric patients who had committed violent offenses or set fires. METHODS: One hundred fourteen male alcoholic violent offenders and fire setters were followed up for an average of 4.5 years after release from prison. At the beginning of their incarceration, the first half of the offenders were administered clinical diagnostic interviews, whereas the latter half received the Structured Clinical Interview for DSM-III (SCID) that was blind rated. A structured family history questionnaire was administered to all available first-degree relatives of offenders. The offenders also received lumbar punctures for monoamine metabolites, an oral glucose tolerance test, and a measurement of fasting plasma cholesterol level. At the end of the follow-up, the Finnish criminal registry was searched for recidivist crimes. RESULTS: Among all offenders, low cerebrospinal fluid (CSF) 5-hydroxyindoleacetic acid (5-HIAA) and homovanillic acid (HVA) concentrations were associated with a family history positive for paternal alcoholism with violence. Low plasma cholesterol concentration was associated with a family history positive for paternal alcoholism without violence. The recidivists, who committed violent offenses or set fires during the follow-up period, had low CSF 5-HIAA and 3-methoxy-4-hydroxyphenylglycol (MHPG) concentrations compared with those in nonrecidivists. Early family environments of the recidivists, compared with those of the nonrecidivists, were characterized by common paternal absence from and presence of brothers at home. CONCLUSION: Among male alcoholic violent offenders and fire setters, low CSF 5-HIAA and HVA concentrations are strongly associated with a family history positive for paternal violence and alcoholism, while low fasting plasma cholesterol concentration is associated with a family history positive for paternal alcoholism. Recidivist violent offenders and fire setters are predicted by low CSF 5-HIAA and MHPG concentrations and a developmental history positive for early paternal absence from and presence of brothers in the family of origin.


Assuntos
Alcoolismo/diagnóstico , Piromania/diagnóstico , Psiquiatria Legal , Violência , Adulto , Alcoolismo/líquido cefalorraquidiano , Alcoolismo/epidemiologia , Colesterol/sangue , Comorbidade , Direito Penal , Família , Finlândia/epidemiologia , Piromania/líquido cefalorraquidiano , Piromania/epidemiologia , Seguimentos , Ácido Homovanílico/líquido cefalorraquidiano , Humanos , Ácido Hidroxi-Indolacético/líquido cefalorraquidiano , Masculino , Transtornos Mentais/líquido cefalorraquidiano , Transtornos Mentais/diagnóstico , Transtornos Mentais/epidemiologia , Metoxi-Hidroxifenilglicol/líquido cefalorraquidiano , Prisioneiros/estatística & dados numéricos , Estudos Prospectivos , Escalas de Graduação Psiquiátrica , Recidiva , Sistema de Registros
9.
Arch Gen Psychiatry ; 55(11): 989-94, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9819067

RESUMO

BACKGROUND: In mice, quantitative trait locus studies and behavioral evaluation of animals deleted for 5-HT1B have implicated this serotonin autoreceptor in alcohol consumption and aggressive behavior. We therefore investigated whether the 5-HT1B gene (HTR1B) is linked to alcoholism with aggressive and impulsive behavior in the human, as represented by 2 psychiatric diagnoses: antisocial personality disorder and intermittent explosive disorder comorbid with alcoholism. METHODS: Linkage was first tested in 640 Finnish subjects, including 166 alcoholic criminal offenders, 261 relatives, and 213 healthy controls. This was followed by a study in a large multigenerational family derived from a Southwestern American Indian tribe (n=418) with a high rate of alcoholism. All subjects were psychiatrically interviewed, blind-rated for psychiatric diagnoses, and typed for a HTR1B G861C polymorphism and for a closely linked short-tandem repeat locus, D6S284. Linkage was evaluated in sib pairs, and by using an association approach in which pedigree randomization corrects for nonindependence of observations on related subjects. RESULTS: In Finnish sib pairs, antisocial alcoholism showed significant evidence of linkage to HTR1B G861C (P=.04) and weak evidence with D6S284 (P=.06). By association analysis, the 183 Finnish antisocial alcoholics had a significantly higher HTR1B-861C allele frequency than the other 457 Finns we studied (P=.005). In the Southwestern American Indian tribe, significant sib pair linkage of antisocial alcoholism to HTR1B G861C (P=.01) was again observed, and there was also significant linkage to D6S284 (P=.01). CONCLUSION: These results suggest that a locus predisposing to antisocial alcoholism may be linked to HTR1B at 6q13-15.


Assuntos
Alcoolismo/genética , Transtorno da Personalidade Antissocial/genética , Transtornos Disruptivos, de Controle do Impulso e da Conduta/genética , Ligação Genética , Receptores de Serotonina/genética , Adolescente , Adulto , Alcoolismo/epidemiologia , Animais , Transtorno da Personalidade Antissocial/epidemiologia , Sequência de Bases , Comorbidade , Transtornos Disruptivos, de Controle do Impulso e da Conduta/epidemiologia , Feminino , Finlândia/epidemiologia , Finlândia/etnologia , Genótipo , Humanos , Indígenas Norte-Americanos/genética , Masculino , Camundongos , Dados de Sequência Molecular , Linhagem , Polimorfismo Genético , Receptor 5-HT1B de Serotonina , Sudoeste dos Estados Unidos/epidemiologia , Sequências de Repetição em Tandem/genética
10.
Arch Gen Psychiatry ; 55(7): 593-602, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9672049

RESUMO

BACKGROUND: Tryptophan hydroxylase (TPH) is the rate-limiting enzyme in the synthesis of serotonin. Low turnover rate of this monoamine neurotransmitter is associated with impaired impulse control. We previously reported that, in Finns, TPH genotype was associated with suicidality, a pathophysiological mechanism that may involve impaired impulse control. METHODS: Association and sib-pair linkage analyses of a polymorphism in intron 7 of the TPH gene with suicidality, alcoholism, and the Karolinska Scales of Personality were conducted in 804 Finnish alcoholic offenders, controls, and their relatives, in a sample that included 369 sib pairs. RESULTS: The association of the TPH 17 779C (L) allele to suicidality in impulsive offenders reported previously was replicated in a new group of Finnish offenders (P=.001, n=122). The intron 7 variant in the TPH gene showed significant evidence for linkage to suicidality (P=.006 in unaffected sib pairs), severe suicide attempts (P=.006 in unaffected sib pairs; regression: P=.01), alcoholism (P=.003 in unaffected sib-pairs; regression: P=.02), and Karolinska Scales of Personality socialization score (regression: P=.002). CONCLUSIONS: The status of the TPH A779C allele as a marker for suicidality was replicated and linkage with alcoholism and Karolinska Scales of Personality socialization score was also observed. A functional variant(s) in or close to the TPH gene may predispose individuals to suicidality and other behaviors thought to be influenced by serotonin.


Assuntos
Alcoolismo/genética , Marcadores Genéticos , Tentativa de Suicídio/estatística & dados numéricos , Triptofano Hidroxilase/genética , Adulto , Alcoolismo/diagnóstico , Alcoolismo/epidemiologia , Transtornos Disruptivos, de Controle do Impulso e da Conduta/epidemiologia , Transtornos Disruptivos, de Controle do Impulso e da Conduta/genética , Família , Finlândia/epidemiologia , Ligação Genética , Variação Genética , Genótipo , Humanos , Íntrons , Masculino , Modelos Genéticos , Personalidade/classificação , Personalidade/genética , Polimorfismo Genético , Prisioneiros/estatística & dados numéricos , Análise de Regressão , Serotonina/genética , Tentativa de Suicídio/classificação
11.
Arch Gen Psychiatry ; 55(10): 936-40, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9783565

RESUMO

BACKGROUND: The heritability of interindividual variation in anxiety and other aspects of personality establishes that variants of genes influence these traits. A functional polymorphism in the promoter of the human serotonin transporter gene (SLC6A4*C) was identified and found to be linked to an anxiety-related personality trait, Neuroticism. The polymorphism affects gene transcription and, ultimately, gene function. We have attempted to confirm the role of SLC6A4*C in anxiety-related personality traits by sibpair analysis and association studies. METHODS: Sibpair linkage analysis and association study were performed in 655 Finns. The index cases were 182 alcoholic criminal offenders, through which 258 relatives were ascertained to obtain 366 sibpairs. In addition, 215 unrelated population controls were collected. Each individual was psychiatrically interviewed, blind-rated for DSM-III-R diagnoses, and assessed with the Tridimensional Personality Questionnaire. RESULTS: The sibpair analysis revealed a positive linkage between SLC6A4*C and the 2 anxiety-related subdimensions of Harm Avoidance: HA1 (Anticipatory Worry) and HA2 (Fear of Uncertainty) (P = .003). However, there was no consistent association between SLC6A4*C and any Tridimensional Personality Questionnaire trait. CONCLUSIONS: In the present study we replicated the relationship of SLC6A4*C to anxiety by sibpair linkage analysis but found no evidence of association, raising the question of whether SLC6A4*C locus is itself affecting anxiety or is linked to another still unknown functional variant.


Assuntos
Ansiedade/genética , Proteínas de Transporte/genética , Glicoproteínas de Membrana/genética , Proteínas de Membrana Transportadoras , Proteínas do Tecido Nervoso , Personalidade/genética , Regiões Promotoras Genéticas/genética , Serotonina/genética , Alcoolismo/genética , Proteínas de Transporte/fisiologia , Crime , Ligação Genética , Humanos , Glicoproteínas de Membrana/fisiologia , Reação em Cadeia da Polimerase , Polimorfismo Genético , Regiões Promotoras Genéticas/fisiologia , Serotonina/fisiologia , Proteínas da Membrana Plasmática de Transporte de Serotonina , Transcrição Gênica/fisiologia
12.
Mol Endocrinol ; 12(9): 1420-31, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9731709

RESUMO

Using an ATP-depletion paradigm to augment glucocorticoid receptor (GR) binding to the nuclear matrix, we have identified a minimal segment of the receptor that constitutes a nuclear matrix targeting signal (NMTS). While previous studies implicated a role for the receptor's DNA-binding domain in nuclear matrix targeting, we show here that this domain of rat GR is necessary, but not sufficient, for matrix targeting. A minimal NMTS can be generated by linking the rat GR DNA-binding domain to either its tau2 transactivation domain in its natural context, or a heterologous transactivation domain derived from the Herpes simplex virus VP16 protein. The transactivation and nuclear matrix-targeting activities of tau2 are separable, as transactivation mutants were identified that either inhibited or had no apparent effect on matrix targeting of tau2. A functional interaction between the NMTS of rat GR and the RNA-binding nuclear matrix protein hnRNP U was revealed in cotransfection experiments in which hnRNP U overexpression was found to interfere with the transactivation activity of GR derivatives that possess nuclear matrix-binding capacity. We have therefore ascribed a novel function to a steroid hormone transactivation domain that could be an important component of the mechanism used by steroid hormone receptors to regulate genes in their native configuration within the nucleus.


Assuntos
DNA/metabolismo , Sinais de Localização Nuclear , Receptores de Glucocorticoides/metabolismo , Ativação Transcricional , Trifosfato de Adenosina/metabolismo , Animais , Western Blotting , Células CHO , Cricetinae , Ribonucleoproteínas Nucleares Heterogêneas Grupo U , Ribonucleoproteínas Nucleares Heterogêneas , RNA/metabolismo , Ratos , Ribonucleoproteínas/metabolismo
13.
Mol Cell Endocrinol ; 399: 103-9, 2015 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-25258300

RESUMO

The cannabinoid receptor subtype 1 gene CNR1 is not only associated with phenotypes such as cognitive performance, addiction and anxiety, but is also known to be crucially involved in responses to acute and chronic psychological and cellular stress conditions. Functional analysis of the 5' untranslated regions of the five known mRNA variants of the human CNR1 gene revealed that two of these variants contain upstream open reading frames that are able to modulate gene expression both under baseline condition and conditions of cellular stress including hypoxia, glucose restriction and hyperthermia. The upstream open reading frames might provide a mechanism that enables the cannabinoid 1 receptor to escape the general repression of protein synthesis that is typical for conditions of cellular stress.


Assuntos
Regiões 5' não Traduzidas/fisiologia , Regulação da Expressão Gênica/fisiologia , Fases de Leitura Aberta/fisiologia , Receptor CB1 de Canabinoide/biossíntese , Estresse Fisiológico , Células HEK293 , Humanos
14.
FEBS Lett ; 292(1-2): 205-9, 1991 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-1959608

RESUMO

Isolated interphase lamin C, obtained from Ehrlich ascites tumor cells, was digested by Lys-C endoproteinase, the resulting peptides separated by reversed-phase HPLC and subjected to microsequencing in order to identify phosphorylation sites in interphase and following phosphorylation in vitro by cdc2-kinase, protein kinase C (PKC) and protein kinase A (PKA), respectively. Nuclear lamin C showed partial phosphorylation of Ser392 and Ser409, and possibly Ser407 in interphase. Phosphorylation was increased in response to cdc2-kinase at Ser390 and Ser392 and to PKC at Ser572. The N-terminal peptide (aa 1-32) containing consensus sequences for the 3 kinases was phosphorylated by cdc2-kinase, PKC and PKA. The sequence data suggests that multiple molecular switches via lamina modification control the dynamic behaviour of the nucleoskeleton during the cell cycle.


Assuntos
Lamina Tipo A , Proteínas Nucleares/metabolismo , Sequência de Aminoácidos , Animais , Autorradiografia , Proteína Quinase CDC2/metabolismo , Cromatografia Líquida de Alta Pressão , Eletroforese em Gel de Poliacrilamida , Laminas , Camundongos , Dados de Sequência Molecular , Fosforilação , Proteína Quinase C/metabolismo , Proteínas Quinases/metabolismo
15.
Curr Pharm Des ; 10(23): 2817-26, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15379670

RESUMO

Glucocorticoids are the first line medication used in the therapy of many severe inflammatory disorders. They exert their activity through binding to the glucocorticoid receptor, a ligand-dependent transcription factor, and result in either activation or repression of a large set of glucocorticoid responsive genes. The desired immunosuppressive effect is apparently due largely to the down-regulation of a variety of pro-inflammatory factors, whereas adverse reactions such as corticoid-induced diabetes and osteoporosis could be connected to the inappropriate activation of genes involved in the control of metabolic processes. The discovery of improved glucocorticoids, which maintain beneficial therapeutic activity together with a diminished risk of side effects, focuses on ligands that lead to repression rather than activation of genes targeted by the glucocorticoid receptor. Current drug-screening programs have yielded a number of molecules including steroidal as well as non-steroidal compounds, which preferentially induce receptor-mediated repression. The characterization of these novel glucocorticoids in several in vitro and in vivo models for their immune modulating activity marks an important step towards the development of a new class of safer glucocorticoid preparations.


Assuntos
Receptores de Glucocorticoides/genética , Ativação Transcricional , Animais , Humanos , Ligantes , Modelos Moleculares
16.
J Steroid Biochem Mol Biol ; 78(1): 59-65, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11530285

RESUMO

The glucocorticoid receptor (GR) is a ligand dependent transcription factor, which regulates the transcription of multiple hormone-dependent genes. The transcriptional regulation by GR takes place by interaction of GR with the basal transcription machinery and by recruiting glucocorticoid receptor interacting proteins (GRIPs). Previously we identified hnRNP U/SAF-A as a factor interfering with GR-dependent transcription by repressing glucocorticoid induced activation. To gain insight into the mechanisms that govern this interference, we have now investigated the transcription of GR-dependent reporter genes in Ltk(-) cells transiently transfected with a variety of hnRNP U constructs. We demonstrate that a hnRNP U construct lacking the GR-binding domain acts as a dominant negative factor that now enhances GR-driven transcription. In addition, hnRNP U repression of glucocorticoid induced transcription was found to be dependent on the amount of cotransfected GR, where a high amount of GR leads to ligand-inducible repression of GR-dependent reporter gene activity by hnRNP U, whereas low amounts of GR showed nearly no effect. The relative concentrations of GR, hnRNP U and DNA-binding sites for GR are important for the effect of hnRNP U on transcription, suggesting a model where hnRNP-U acts as a storage site for intranuclear GR.


Assuntos
Glucocorticoides/metabolismo , Ribonucleoproteínas/farmacologia , Transcrição Gênica , Sítios de Ligação , Linhagem Celular , Núcleo Celular/metabolismo , Separação Celular , Cloranfenicol O-Acetiltransferase/metabolismo , Células Eucarióticas/metabolismo , Citometria de Fluxo , Genes Dominantes , Genes Reporter , Ribonucleoproteínas Nucleares Heterogêneas Grupo U , Ribonucleoproteínas Nucleares Heterogêneas , Humanos , Ligantes , Modelos Genéticos , Mutação , Plasmídeos/metabolismo , Ligação Proteica , Estrutura Terciária de Proteína , RNA Polimerase II/metabolismo , Transfecção
17.
J Steroid Biochem Mol Biol ; 56(1-6 Spec No): 39-45, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8603046

RESUMO

Glucocorticoids and thyroid hormones induce complex responses in about every mammalian tissue. These effects are mediated by the transcription factor function of the corresponding nuclear receptors, which in most cases achieve the observed regulatory strength in synergy with other factors. Here we describe the functional interaction of the glucocorticoid receptor (GR) with liver-specific transcription factors, the functional synergy of GR with the thyroid hormone receptor (TR), the synergizing sub-domains of the TR, and finally the direct interaction of the GR with other proteins.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Proteínas Nucleares/fisiologia , Proteínas Oncogênicas v-erbA/fisiologia , Receptores de Glucocorticoides/fisiologia , Receptores dos Hormônios Tireóideos/fisiologia , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/fisiologia , Transcrição Gênica/efeitos dos fármacos , Animais , Proteínas Estimuladoras de Ligação a CCAAT , Carcinoma Hepatocelular/patologia , Proteínas de Transporte/isolamento & purificação , Proteínas de Transporte/metabolismo , Dexametasona/farmacologia , Indução Enzimática/efeitos dos fármacos , Genes Reporter , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Transgênicos , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Receptores de Glucocorticoides/efeitos dos fármacos , Sequências Reguladoras de Ácido Nucleico , Triptofano Oxigenase/biossíntese , Triptofano Oxigenase/genética , Células Tumorais Cultivadas
18.
Brain Res Bull ; 4(6): 793-7, 1979.
Artigo em Inglês | MEDLINE | ID: mdl-526860

RESUMO

Melanin was measured by a spectrophotofluorometric method in the brains of albino rats from birth to 20 months of age. The concentration of brain melanin increased from Day 1 until adult levels were reached at 1 month. Between 1 and 20 months of age no significant differences were found in brain melanin. Daily injections of alpha-MSH, MIF-I, melatonin, or diluent did not consistently alter the concentration of brain melanin and a high (40%) protein diet did not appear to increase it. After concurrent injections of alpha-MSH and theophylline, an initial elevation of the level of melanin in the brain of newborn rats was found beginning at Day 8 but by age 1 month the values had returned to control levels. The results show that the largest changes in the concentrations of melanin in the brains of rats occur with age during the first month after birth.


Assuntos
Envelhecimento , Encéfalo/metabolismo , Melaninas/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Proteínas Alimentares/administração & dosagem , Hormônios Estimuladores de Melanócitos/farmacologia , Melatonina/farmacologia , Ratos , Teofilina/farmacologia
19.
Psychol Aging ; 2(3): 211-6, 1987 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3268211

RESUMO

We describe the development of an Orientation Questionnaire (OQ), a standardized measure of the impairment of an older person's ability to communicate orientation information. Starting with a pool of selected items, we made a series of revisions that resulted in a 17-item questionnaire with a score range from 0 through 40 points. In additional studies we determined that OQ scores evidence adequate reliability (test-retest r = .969) and adequate validity (r with nurse ratings = .798 and .793; r with behavioral assessment = .807). The OQ scores discriminated groups on the basis of environmental structure (community vs. nursing home vs. neuropsychiatric hospital) and psychiatric diagnosis (organic vs. schizophrenic vs. no diagnosis). Tentative classification data are presented, and uses of the OQ are discussed.


Assuntos
Transtornos Cognitivos/psicologia , Confusão/psicologia , Testes Neuropsicológicos , Orientação , Idoso , Confusão/diagnóstico , Demência/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psicometria , Valores de Referência , Psicologia do Esquizofrênico
20.
Phys Med Biol ; 26(6): 1055-67, 1981 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7323145

RESUMO

A constant temperature perfusion system employing four heat exchangers has been developed in which perfusion fluid is heated from room temperature to 37 +/- 10 -4 degrees C for precision heat flow measurements on isolated working rat hearts. The temperature characteristics have been established and mathematical expressions developed to identify and quantify spurious thermal events. The system is a refinement of existing perfusion systems for metabolic and mechanical investigations which meets the complete requirements of myocardial energetics. It can also be used for experiments which include high precision temperature measurements on isolated working hearts or for thermal investigations on other isolated perfused organs where a highly stabilised temperature base line is required over perfusion flows from 0-100 cm3 min -1.


Assuntos
Metabolismo Energético , Coração/fisiologia , Animais , Regulação da Temperatura Corporal , Calorimetria , Perfusão , Ratos , Temperatura
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