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1.
Oncogene ; 31(48): 4996-5006, 2012 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-22310286

RESUMO

TRAIL (TNF (tumour necrosis factor)-related apoptosis-inducing ligand) a putative anti-cancer cytokine induces apoptosis through DISC (death-inducing signalling complex)-mediated activation of caspase-8 and/or cleavage of Bid. TRAIL is relatively specific for tumour cells but primary chronic lymphocytic leukaemia and mantle cell lymphoma (MCL) cells are resistant. Herein, we show that cellular metabolism influences cell death and that MCL cells (Z138 cell line) can survive/proliferate in glucose-free media by switching from aerobic glycolysis to 'coupled' oxidative phosphorylation. Extracellular flux analysis and mitochondrial inhibitors reveal that in the absence of glycolysis, Z138 cells have enhanced respiratory capacity coupled to ATP synthesis, similar to 'classical' state 3 mitochondria. Conversely, 2-deoxyglucose (2DG) blocked glycolysis and partially inhibited glycolytic-dependent oxidative phosphorylation, resulting in a 50% reduction in cellular ATP levels. Also, 2DG sensitised Z138 cells to TRAIL and induced a marked decrease in caspase-8, -3, cFLIP(S), Bid and Mcl-1 expression but Bak remained unchanged, altering the Mcl-1/Bak ratio, facilitating cytochrome c release and cell death. Conversely, under glucose-free conditions, Z138 cells were less sensitive to TRAIL with reduced TRAIL-R1/R2 surface receptor expression and impaired DISC formation. Anti-apoptotic proteins Bcl-2 and XIAP were up-regulated while pro-apoptotic BAX was down-regulated. Additionally, mitochondria had higher levels of cytochrome c and ultrastucturally exhibited a condensed configuration with enhanced intracristal spaces. Thus, metabolic switching was accompanied by mitochondrial proteome and ultrastructural remodelling enabling enhanced respiration activity. Cytochrome c release was decreased in glucose-free cells, suggesting that either pore formation was inhibited or that cytochrome c was more tightly bound. Glucose-free Z138 cells were also resistant to intrinsic cell death stimuli (ABT-737 and ionising radiation). In summary, in MCL cells, the anti-glycolytic effects of 2DG and glucose restriction produced opposite effects on TRAIL-induced cell death, demonstrating that mitochondrial metabolism directly modulates sensitivity of tumour cells to apoptosis.


Assuntos
Linfoma de Célula do Manto/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/fisiologia , Aerobiose , Apoptose/fisiologia , Linhagem Celular Tumoral , Meios de Cultura , Citocromos c/metabolismo , Glicólise , Humanos , Linfoma de Célula do Manto/patologia , Mitocôndrias/fisiologia , Fosforilação Oxidativa
2.
Percept Mot Skills ; 97(3 Pt 1): 743-52, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14738334

RESUMO

The preliminary study investigated metabolic anomalies in children and teenagers with Irlen Syndrome, particularly in relation to the levels of n-3 and n-6 essential fatty acids, plasma cholesterol levels, and the relative abundance of plasma saturated fatty acids. The experimental group involved 13 subjects with Irlen Syndrome (M=13.3 yr., SD=2.5 yr.), with a comparison group of 16 age- and sex-matched controls (M=13.8 yr., SD=2.4 yr.). The Irlen Syndrome group were selected from people referred for help with reading and writing problems. The control group were primarily recruited from the general public. All subjects were screened for symptoms of the syndrome using the Scotopic Sensitivity Syndrome Screening Manual. Samples of whole blood were collected and plasma extracted. Metabolites were compared using the Student t test. There were no differences in n-3 and n-6 essential fatty acids between Irlen Syndrome and control groups, although the former group had lower mean levels in most of these essential fatty acids. Total plasma cholesterol level was significantly decreased for the Irlen Syndrome group, and there was a significant increase in the relative abundance of the odd-chain fatty acid, heptadecanoic acid. The differences in heptadecanoic acid may have implications for altered membrane function and neurotransmission. The differences in plasma cholesterol levels, as well as heptadecanoic acid, may also point to the presence of viral or bacterial infection.


Assuntos
Colesterol/sangue , Transtornos da Percepção/sangue , Transtornos da Percepção/fisiopatologia , Percepção Visual/fisiologia , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/complicações , Criança , Cromatografia Gasosa , Feminino , Humanos , Masculino , Transtornos da Percepção/complicações , Estudantes , Síndrome
3.
Percept Mot Skills ; 93(2): 486-504, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11769907

RESUMO

This study investigated the biological basis of visual processing disabilities in adults with Chronic Fatigue Syndrome. The study involved 61 adults with symptoms of Chronic Fatigue Syndrome who were screened for visual processing problems (Irlen Syndrome) and divided into two groups according to the severity of symptoms of Irlen Syndrome. Significant variations were identified in blood lipids and urine amino and organic acids of the two groups, which may be indicative of activation of the immune system due to some infective agent. It was suggested that metabolic profiling may help the development of more valid diagnostic categories and allow more investigation of immune system dysfunction as a possible causal factor in a range of learning and behaviour disorders.


Assuntos
Síndrome de Fadiga Crônica/imunologia , Infecções/imunologia , Transtornos da Percepção/imunologia , Percepção Visual , Adulto , Pós-Imagem/fisiologia , Comorbidade , Diagnóstico Diferencial , Síndrome de Fadiga Crônica/diagnóstico , Feminino , Humanos , Hidroxiprolina/urina , Infecções/diagnóstico , Lipídeos/sangue , Masculino , Metilistidinas/urina , Transtornos da Percepção/diagnóstico , Prolina/urina , Síndrome , Percepção Visual/fisiologia
4.
Percept Mot Skills ; 91(3 Pt 1): 707-24, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11153837

RESUMO

The familial incidence of Scotopic Sensitivity/Irlen Syndrome was investigated in two samples. One sample involved parents and siblings of 126 children identified with symptoms who had been referred for screening. The other sample involved parents and siblings of 33 children who had been identified with symptoms through mass screening of all children in Grades 3 to 6 at two local schools. Two different samples were taken to investigate the possibility of parental referral bias. Familial incidence may be inflated in a referred sample because some parents may be aware of their own symptoms and actively seek assistance. For the sample of children referred for screening, there was an 81% chance of either one or both parents showing similar symptoms and a 76% chance of siblings being similarly affected. For the sample of children identified through school screening, there was an 85%, chance of either one or both parents showing similar symptoms and a 54% chance of siblings being similarly affected. The data confirm previous estimates of incidence and suggest that Scotopic Sensitivity/Irlen Syndrome may be a genetically-based deficit in visual processing.


Assuntos
Dislexia/genética , Testes Genéticos , Programas de Rastreamento , Transtornos da Percepção/genética , Encaminhamento e Consulta , Percepção Visual/genética , Adulto , Criança , Dislexia/diagnóstico , Educação Inclusiva , Feminino , Humanos , Incidência , Masculino , New South Wales , Transtornos da Percepção/diagnóstico
5.
Percept Mot Skills ; 89(1): 83-113, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10544403

RESUMO

This study investigated the effects of using coloured filters on reading speed, accuracy, and comprehension as well as on perception of academic ability. A double-masked, placebo-controlled crossover design was used, with subjects being assessed over a period of 20 mo. There were three treatment groups (Placebo filters, Blue filters, and Optimal filters) involving 113 subjects with "reading difficulties", ranging in age from 9.2 yr. to 13.1 yr. and with an average discrepancy between chronological age and reading age of 1.8 yr. The 35 controls (who did not use coloured filters) ranged in age from 9.4 yr. to 12.9 yr., with an average discrepancy between chronological age and reading age of 2.1 yr. The treatment groups increased at a significantly greater rate than the control group in reading accuracy and reading comprehension but not for speed of reading. For self-reported perception of academic ability, two of the three treatment groups showed significantly greater increases than the control group. The larger improvements for treatment groups in reading comprehension may be related to a reduction in print and background distortions allowing attention to be directed to the processing of continuous text rather than to the identification of individual words. A reduction in print distortion, however, may not be sufficient to generate improved word-identification skills without additional remedial support, and this may be indicated by the nonsignificant increase in rate of reading.


Assuntos
Logro , Cor , Dislexia/terapia , Percepção de Forma , Mascaramento Perceptivo , Leitura , Doenças Retinianas/fisiopatologia , Adolescente , Aptidão , Atenção , Criança , Dislexia/fisiopatologia , Óculos , Feminino , Seguimentos , Percepção de Forma/fisiologia , Humanos , Luz/efeitos adversos , Masculino , Óptica e Fotônica , Distorção da Percepção , Placebos , Autoimagem , Inquéritos e Questionários , Resultado do Tratamento
6.
Percept Mot Skills ; 88(1): 35-52, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10214632

RESUMO

This study investigated the long-term effects of using coloured filters on the frequency and type of errors in oral reading. A double-masked, placebo-controlled crossover experimental design was used, with subjects being assessed over a period of 20 months. There were three experimental groups (Placebo tints, Blue tints, and Diagnosed tints) involving 113 subjects with reading difficulties, ranging in age from 9.2 yr. to 13.1 yr. The 35 controls (ranging in age from 9.4 yr. to 12.9 yr.) had reading difficulties but did not require coloured filters. There was a significant improvement for all groups in the accuracy of miscues over the period, although experimental groups over-all did not improve at a significantly different rate than the control group. The failure to find significantly greater improvement for the experimental groups over the control group for the total period, despite subjects' reports of improved print clarity, may be partly related to the lack of effective letter-sound analysis and synthesis skills and to the use of a word-identification strategy of guessing based on partial visual analysis.


Assuntos
Cor , Adaptação à Escuridão , Dislexia/reabilitação , Lentes/estatística & dados numéricos , Transtornos da Percepção/reabilitação , Leitura , Percepção Visual , Adolescente , Criança , Estudos Cross-Over , Escolaridade , Feminino , Humanos , Estudos Longitudinais , Masculino , Mascaramento Perceptivo , Fonética , Placebos , Fala , Resultado do Tratamento
7.
Subst Use Misuse ; 33(6): 1367-73, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9603275

RESUMO

This study examines the perceptions of the social aspects, triggers, and effects of chamba (marijuana) use among psychiatric patients at Zomba Mental Hospital in Malawi. Focus groups were used to elicit responses from 44 male and 10 female psychiatric patients about their perceptions of chamba use in Malawi. This study provides insight into these patients' perceptions of the triggers and effects of their chamba use, and it has implications for the development of treatment and prevention programs for chamba users in Malawi.


Assuntos
Atitude Frente a Saúde/etnologia , Abuso de Maconha/etnologia , Transtornos Mentais/psicologia , Adulto , Feminino , Grupos Focais , Humanos , Malaui , Masculino , Abuso de Maconha/psicologia
8.
Percept Mot Skills ; 83(3 Pt 1): 1043-55, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8961341

RESUMO

The familial incidence of Scotopic Sensitivity/Irlen Syndrome was investigated using parents of 751 children identified with symptoms. Children were identified by methods independent of their parents' symptoms or lack of symptoms. For these children, there was an 84% chance of either one or both parents showing similar symptoms, with similar numbers of mothers identified with symptoms as fathers. The data suggest that Scotopic Sensitivity/Irlen Syndrome may be a genetically based deficit in visual processing, but the simplest genetic models do not appear to fit.


Assuntos
Dislexia/genética , Genótipo , Transtornos da Percepção/genética , Doenças Retinianas/genética , Percepção Visual/genética , Adolescente , Criança , Sensibilidades de Contraste/genética , Dislexia/diagnóstico , Educação Inclusiva , Feminino , Humanos , Masculino , Transtornos da Percepção/diagnóstico , Doenças Retinianas/diagnóstico , Fatores de Risco
9.
J Med Chem ; 39(1): 143-8, 1996 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-8568801

RESUMO

A series of substituted phenethyl derivatives of 3-benzisothiazolylpiperazine incorporating potent D2 and 5-HT2A antagonist activity was investigated as an approach to a novel atypical antipsychotic agent. The in vitro profile of 8e from this series is a combination of D2 receptor affinity comparable to the typical antipsychotic agent haloperidol and a 5-HT2A/D2 ratio comparable to the atypical agent clozapine. In vivo 8e possesses activity consistent with an efficacious antipsychotic agent with less tendency to induce extrapyramidal side effects in man.


Assuntos
Antipsicóticos/farmacologia , Piperazinas/farmacologia , Antagonistas da Serotonina/farmacologia , Tiazóis/farmacologia , Anfetamina/farmacologia , Animais , Antipsicóticos/química , Apomorfina/farmacologia , Aprendizagem da Esquiva/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Catalepsia/metabolismo , Clozapina/farmacologia , Dopamina/metabolismo , Dopamina/farmacologia , Desenho de Fármacos , Humanos , Estrutura Molecular , Fosfatidilinositóis/antagonistas & inibidores , Fosfatidilinositóis/metabolismo , Piperazinas/química , Prazosina/antagonistas & inibidores , Prazosina/metabolismo , Ratos , Receptores Adrenérgicos/metabolismo , Receptores Dopaminérgicos/metabolismo , Antagonistas da Serotonina/química , Tiazóis/química
10.
Mol Cell Biol ; 15(3): 1398-404, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7862133

RESUMO

Pancreatic beta-cell-type-specific transcription of the insulin gene is principally controlled by trans-acting factors which influence insulin control element (ICE)-mediated expression. The ICE activator is composed, in part, of the basic helix-loop-helix proteins E12, E47, and E2-5 encoded by the E2A gene. Previous experiments showed that ICE activation in beta cells was repressed in vivo by the c-jun proto-oncogene (E. Henderson and R. Stein, Mol. Cell. Biol. 14:655-662, 1994). Here we focus on the mechanism by which c-Jun inhibits ICE-mediated activation. c-Jun was shown to specifically repress the transactivation potential of the E2A proteins. Thus, we found that the activity of GAL4:E2A fusion constructs was inhibited by c-Jun. The transrepression capabilities of c-Jun were detected only in pancreatic islet cell lines that contained a functional ICE activator. Repression of GAL4:E2A was mediated by the basic leucine zipper regions of c-Jun, which are also the essential regions of this protein necessary for controlling ICE activator-stimulated expression in vivo. The specific target of c-Jun repression was the transactivation domain (located between amino acids 345 and 408 in E12 and E47) conserved in E12, E47, and E2-5. In contrast, the activation domain unique to the E12 and E47 proteins (located between amino acids 1 and 99) was unresponsive to c-Jun. Our results indicate that c-Jun inhibits insulin gene transcription in beta cells by reducing the transactivation potential of the E2A proteins present in the ICE activator complex.


Assuntos
Proteínas E2 de Adenovirus/metabolismo , Regulação da Expressão Gênica , Genes jun , Insulina/biossíntese , Insulina/genética , Ilhotas Pancreáticas/metabolismo , Proteínas Proto-Oncogênicas c-jun/metabolismo , Transcrição Gênica , Ativação Transcricional , Adenoviridae/genética , Adenoviridae/metabolismo , Proteínas E2 de Adenovirus/biossíntese , Animais , Sequência de Bases , Linhagem Celular , Cricetinae , Primers do DNA , Células HeLa , Humanos , Camundongos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas c-jun/biossíntese , Transfecção
11.
Mol Cell Biol ; 14(10): 6704-14, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7935390

RESUMO

Pancreatic beta-cell-type-specific transcription of the insulin gene is principally regulated by a single cis-acting DNA sequence element, termed the insulin control element (ICE), which is found within the 5'-flanking region of the gene. The ICE activator is a heteromeric complex composed of an islet alpha/beta-cell-specific factor associated with the ubiquitously distributed E2A-encoded proteins (E12, E47, and E2-5). We describe the isolation and characterization of a cDNA for a protein present in alpha and beta cells, termed INSAF for insulin activator factor, which binds to and activates ICE-mediated expression. INSAF was isolated from a human insulinoma cDNA library. Transfection experiments demonstrated that INSAF activates ICE expression in insulin-expressing cells but not in non-insulin-expressing cells. Cotransfection experiments showed that activation by INSAF was inhibited by Id, a negative regulator of basic helix-loop-helix (bHLH) protein function. INSAF was also shown to associate in vitro with the bHLH protein E12. In addition, affinity-purified INSAF antiserum abolished the formation of the activator-specific ICE-binding complex. Immunohistochemical studies indicate that INSAF is restricted in terms of its expression pattern, in that INSAF appears to be detected only within the nuclei of islet pancreatic alpha and beta cells. All of these data are consistent with the proposal that INSAF is either part of the ICE activator or is antigenically related to the specific activator required for insulin gene transcription.


Assuntos
Regulação da Expressão Gênica , Insulina/farmacologia , Pâncreas/fisiologia , Sequências Reguladoras de Ácido Nucleico , Proteínas Repressoras , Transativadores/metabolismo , Fatores de Transcrição , Sequência de Aminoácidos , Sequência de Bases , Compartimento Celular , Clonagem Molecular , Proteínas de Ligação a DNA/metabolismo , Humanos , Proteína 1 Inibidora de Diferenciação , Insulinoma/genética , Dados de Sequência Molecular , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Especificidade de Órgãos , Neoplasias Pancreáticas/genética , Ligação Proteica , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Fatores de Transcrição TCF , Transativadores/genética , Proteína 1 Semelhante ao Fator 7 de Transcrição , Ativação Transcricional
12.
Percept Mot Skills ; 79(1 Pt 2): 467-83, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7808885

RESUMO

The effect of tinted nonoptical (Irlen) lenses was investigated with 29 lens-using subjects and a control group of 31 subjects. Assessment of reading four months after the initial screening showed a significant improvement in reading rate and comprehension but not in accuracy. A significant decrease in the number of pauses while reading was also noted for the lens users as well as increases in correlation between word repetition and reading rate and accuracy. The lens users also showed significantly improved scores on a scale of attitude towards school tasks.


Assuntos
Aptidão , Percepção de Cores , Escolaridade , Óculos , Filtração/instrumentação , Leitura , Adolescente , Atitude , Criança , Dislexia/psicologia , Dislexia/terapia , Educação Inclusiva , Feminino , Humanos , Masculino , Distorção da Percepção
13.
J Biol Chem ; 269(4): 2452-60, 1994 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-8300572

RESUMO

Cell type-specific expression of the major differentiated products of alpha (glucagon) and beta (insulin) cells are regulated by sequences found within their 5'-flanking region. Specific transcription of the insulin gene appears to be principally controlled by a single cis-acting DNA element, termed the insulin control element (ICE). The ICE activator acts in combination with other positive regulatory factors that interact within this region to generate the correct, cell type-specific expression. In the present study, we show that the ICE activator is not only present but is functionally active in the islet glucagon-producing alpha cell line, alpha TC6. Analysis of the expression of various transfected insulin enhancer expression plasmids demonstrated that the insulin enhancer is active in alpha TC6 cells, although at a lower level than in beta cells. The reduced transcription from these constructs appears to be a consequence of the lack of other essential positive regulator(s). The alpha TC6 cells were also shown to display neuronal-like properties. Since islet cells appear to evolve from an alpha-like precursor cell that transiently expresses neuronal cell markers, these results would indicate that the ICE activator factor is induced before transcription of the insulin gene in the developing islet.


Assuntos
DNA/metabolismo , Elementos Facilitadores Genéticos , Expressão Gênica , Insulina/biossíntese , Insulina/genética , Ilhotas Pancreáticas/metabolismo , Regiões Promotoras Genéticas , Transcrição Gênica , Animais , Sequência de Bases , Sítios de Ligação , Linhagem Celular , Proteínas de Ligação a DNA/metabolismo , Glucagon/biossíntese , Células HeLa , Humanos , Ilhotas Pancreáticas/citologia , Camundongos , Dados de Sequência Molecular , Neurônios/citologia , Neurônios/metabolismo , Oligodesoxirribonucleotídeos , Ratos , Transfecção
14.
J Learn Disabil ; 23(10): 589-96, 1990 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2280166

RESUMO

Recent evidence suggests that a specific visual-perceptual dysfunction not normally assessed by eye examination should be considered as a significant cause of reading problems. The use of tinted nonoptical (Irlen) lenses to minimize this dysfunction has been hypothesized to result in significant improvement in reading and other visual-processing skills. The present study involved 44 subjects with reading disabilities (33 males, 11 females), aged between 9 years 1 month and 15 years 11 months, who had been provided with Irlen lenses. Assessment of subjects' perception of their own ability (Student's Perception of Ability Scale) 6 and 12 months after the fitting of Irlen lenses indicated a significant improvement in attitude to school and to basic academic skills. Subjects also demonstrated significant improvements in reading comprehension and reading accuracy, but not in rate of reading, when assessed using the Neale Analysis of Reading Ability at 3-, 6-, and 12-month intervals after lens fitting. Differences in the pattern of improvement are discussed in light of previous findings.


Assuntos
Aptidão , Percepção de Cores , Dislexia/terapia , Educação Inclusiva , Óculos , Autoimagem , Percepção Visual , Adolescente , Criança , Dislexia/psicologia , Feminino , Humanos , Masculino
16.
Psychiatr Q ; 58(2): 113-8, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3562679

RESUMO

The effect of a structured program of education on subsequent psychiatric patient compliance with medication-taking was investigated. The subjects consisted of 150 hospitalized patients housed on four acute-care receiving wards and ready for discharge from Fallsview Psychiatric Hospital in Ohio. They were randomly assigned to one of three groups. Results indicated that subjects who received written information with verbal reinforcement were significantly more compliant than the control subjects. These findings suggest that, if the hand-out is discussed with them, the patients given medication handouts similar to those used in the study will comply with medication-taking after discharge at a higher rate than those given no hand-out. Implications of these findings for increased psychiatric patients' post-discharge compliance with medications are discussed.


Assuntos
Transtornos Mentais/tratamento farmacológico , Cooperação do Paciente , Educação de Pacientes como Assunto , Hospitais Psiquiátricos , Humanos , Alta do Paciente , Educação de Pacientes como Assunto/métodos , Distribuição Aleatória
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