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1.
Pilot Feasibility Stud ; 9(1): 61, 2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37076884

RESUMO

BACKGROUND: The Alzheimer's and Music Therapy (ALMUTH) study is the first randomised controlled trial (RCT) design with 12 months of active non-pharmacological therapy (NPT) implementing music therapy (MT) and physical activity (PA) for participants with Alzheimer's disease (AD). The aim of the present article is to retrospectively examine the inclusion of mild-to-moderate Alzheimer's Disease patients into the main ALMUTH study protocol and to determine if continued inclusion of AD patients is warranted. METHODS: The randomised pilot trial was conducted as a parallel three-arm RCT, reflecting the experimental design of the ALMUTH study. The trial was conducted in Bergen, Norway, and randomisation (1:1:1) was performed by an external researcher. The study was open label and the experimental design features two active NPTs: MT and PA, and a passive control (no intervention, CON) in Norwegian speaking patients with AD who still live at home and could provide informed consent. Sessions were offered once per week (up to 90 min) up to 40 sessions over 12 months. Baseline and follow-up tests included a full neuropsychological test battery and three magnetic resonance imaging (MRI) measurements (structural, functional, and diffusion weighted imaging). Feasibility outcomes were assessed and were determined as feasible if they met the target criteria. RESULTS: Eighteen participants with a diagnosis of mild-to-moderate AD were screened, randomised, and tested once at baseline and once after 12-months. Participants were divided into three groups: MT (n = 6), PA (n = 6), and CON (n = 6). Results of the study revealed that the ALMUTH protocol in patients with AD was not feasible. The adherence to the study protocol was poor (50% attended sessions), with attrition and retention rates at 50%. The recruitment was costly and there were difficulties acquiring participants who met the inclusion criteria. Issues with study fidelity and problems raised by staff were taken into consideration for the updated study protocol. No adverse events were reported by the patients or their caregivers. CONCLUSIONS: The pilot trial was not deemed feasible in patients with mild-to-moderate AD. To mitigate this, the ALMUTH study has expanded the recruitment criteria to include participants with milder forms of memory impairment (pre-AD) in addition to expanding the neuropsychological test battery. The ALMUTH study is currently ongoing through 2023. TRIAL REGISTRATION: Norsk Forskningsråd (NFR) funded. Regional Committees for Medical and Health Research Ethics (REC-WEST: reference number 2018/206). CLINICALTRIALS: gov: NCT03444181 (registered retrospectively 23 February 2018, https://clinicaltrials.gov/ct2/show/NCT03444181 ).

2.
Drug Res (Stuttg) ; 66(7): 384-92, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27281448

RESUMO

A pooled analysis is presented of 7 placebo-controlled RCT that investigated lozenges containing ambroxol for pain relief in acute sore throat.2 242 patients were treated with different ambroxol doses or control treatments, 2 183 were evaluable for efficacy. The present analysis is focused on the recommended dose of 20 mg (AXL20): 856 patients were treated with AXL20, 847 with matched placebo lozenges (PL).The average reduction in pain intensity over the first 3 h after the first AXL20 ranged from 38% to 52% of the maximum achievable effect (MAE). The overall treatment difference between AXL20 and PL was 11% (95% CI: 8-13%) of the MAE (post-hoc meta-analysis). The corresponding NNT was 6.0 (CI: 4.7-8.4) for an average pain reduction from baseline of 33% of the MAE over the first 3 h.71.9, 79.0, and 85.3% of the AXL20-patients scored the efficacy as "very good or good" at the end of the 1(st), 2(nd) and 3(rd) day, respectively, vs. 57.5, 64.4, and 70.4% of the PL-patients resulting in odds ratios of 1.9 (CI: 1.5-2.3) for the 1(st), 2.1 (CI: 1.7-2.6) for the 2(nd) and 2.43 (CI: 1.8-3.3) for the 3(rd) day.At the end of treatment 'no redness' or 'slightly red' was scored on pharyngeal inspection in 84.4% and 77.3% of AXL20- and PL-patients (OR: 1.6, CI: 1.3-1.9).AXL20-treatment was well tolerated and is safe and efficacious for acute uncomplicated sore throat of recent onset in adolescent and adult patients.


Assuntos
Ambroxol/efeitos adversos , Ambroxol/uso terapêutico , Faringite/tratamento farmacológico , Administração Oral , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Ambroxol/administração & dosagem , Método Duplo-Cego , Expectorantes/administração & dosagem , Expectorantes/efeitos adversos , Expectorantes/uso terapêutico , Feminino , Humanos , Masculino , Metanálise como Assunto , Pessoa de Meia-Idade , Medição da Dor/efeitos dos fármacos , Comportamento de Sucção , Comprimidos , Adulto Jovem
3.
Respir Res ; 16: 121, 2015 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-26438038

RESUMO

UNLABELLED: Iota-carrageenan (I-C) is active against respiratory viruses in vitro and was effective as nasal spray in three previous clinical trials. The current trial served to further investigate I-C in patients with early common cold symptoms. METHODS: This randomized, placebo-controlled, double-blind phase IV trial was conducted in 200 adult patients with self-diagnosed colds of <48 h' duration that were confirmed by baseline cold symptom scores. Patients were to self-administer 0.12 % I-C or placebo spray (NaCl 0.5 %) four times daily for four to ten days and record symptom information for ten days. Common respiratory viruses were quantified by RT-PCR during pretreatment and on Day 3 or 4. The primary endpoint was the mean total symptom score (TSS) of eight cold symptoms on Days 2-4 (TSS2-4). RESULTS: Patients in both treatment groups had similar baseline TSSs (mean TSS: 6.75 for I-C and 6.79 for placebo). Viruses were detected in baseline samples from 53 of 98 I-C patients (54.1 %) and 54 of 97 placebo patients (55.7 %). Mean ± SE for TSS2-4 was 5.78 ± 0.25 for I-C patients and 6.39 ± 0.25 for placebo (p = 0.0895). Exploratory analyses after unblinding (TSS2-4 excluding a patient with aberrantly high symptom scores [TSS2-4, ex 1pt]; mean of TSS over Days 1-4 [TSS1-4]; change in TSS1-4 relative to baseline [TSS1-4, rel]) demonstrated treatment differences in favor of I-C (p = 0.0364, p = 0.0495 and p = 0.0421, respectively). For patients with quantifiable rhinovirus/enterovirus at baseline, there was a trend towards greater reduction of virus load at Day 3 or 4 (p = 0.0958; I-C: 90.2 % reduction in viral load; placebo: 72.0 %). Treatments were well tolerated with no differences in adverse event rates. CONCLUSIONS: The primary endpoint did not demonstrate a statistically significant difference between I-C and placebo but showed a trend towards I-C benefit. Exploratory analyses indicated significant reduction of cold symptoms in the I-C group relative to placebo during the first four days when symptoms were most severe, and also substantiated I-C's activity against rhinovirus/enterovirus. TRIAL REGISTRATION: NCT01944631 (clinicaltrials.gov).


Assuntos
Antivirais/administração & dosagem , Carragenina/administração & dosagem , Resfriado Comum/tratamento farmacológico , Administração Intranasal , Adolescente , Aerossóis , Antivirais/efeitos adversos , Carragenina/efeitos adversos , Resfriado Comum/diagnóstico , Resfriado Comum/virologia , Método Duplo-Cego , Esquema de Medicação , Enterovirus/efeitos dos fármacos , Enterovirus/patogenicidade , Feminino , Humanos , Masculino , Rhinovirus/efeitos dos fármacos , Rhinovirus/patogenicidade , Autoadministração , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento , Carga Viral , País de Gales , Adulto Jovem
4.
Drug Res (Stuttg) ; 65(12): 658-67, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25782170

RESUMO

OBJECTIVE: Compare the efficacy and tolerability of oral spray formulations delivering 2.5, 5, and 10 mg ambroxol (AXS) per application (4 actuations/application) in relieving acute sore throat vs. spraying a matched placebo solution. DESIGN: Multi-centre, placebo-controlled, randomised, double-blind trial with up to 6 daily applications of the assigned medication for up to 3 days. PATIENTS: 511 outpatients with acute sore throat were enrolled, 494 were treated. TREATMENTS: Up to 6 spray applications per day as needed for up to 3 days. RESULTS: All treatments led to a reduction in pain intensity (PI); the mean cumulative PI-reductions over the first 2 h after the 1(st) dose (SPIDnorm(0-2)) were 24.7, 26.6, 26.0, and 32.2% (SEM: 0.023) of the predose PI for treatment with placebo, and the 2.5, 5, and 10 mg AXS, respectively. These mean reductions were 2 (CI: -3.6; 7.5), 1.3 (CI: -4.3; 6.8), and 7.5 (CI: 2.0;13.1) percent points larger than for placebo. The 2.5 and 5 mg AXS were not distinguishable from placebo, but the 10 mg AXS was evidently superior. The numbers needed to treat (NNT) when comparing 10 mg AXS with placebo, were 9.5 and 8.8 for an average pain relief of 33 and 50% of the maximum achievable effect over the first 2 h. CONCLUSIONS: 10 mg AXS showed a statistically significantly superior pain reduction relative to the placebo spray. Treatment with 10 mg AXS reaches an extent of pain relief that can be accepted to be clinically meaningful and was well tolerated.


Assuntos
Ambroxol/efeitos adversos , Ambroxol/uso terapêutico , Sprays Orais , Dor/complicações , Dor/tratamento farmacológico , Faringite/complicações , Faringite/tratamento farmacológico , Doença Aguda , Adulto , Ambroxol/administração & dosagem , Relação Dose-Resposta a Droga , Método Duplo-Cego , Expectorantes/administração & dosagem , Expectorantes/efeitos adversos , Expectorantes/uso terapêutico , Feminino , Humanos , Masculino , Números Necessários para Tratar , Adulto Jovem
5.
Eur J Neurosci ; 33(1): 189-96, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21073548

RESUMO

Working memory (WM) performance in humans can be improved by structuring and organizing the material to be remembered. For visual and verbal information, this process of structuring has been associated with the involvement of a prefrontal-parietal network, but for non-verbal auditory material, the brain areas that facilitate WM for structured information have remained elusive. Using functional magnetic resonance imaging, this study compared neural correlates underlying encoding and rehearsal of auditory WM for structured and unstructured material. Musicians and non-musicians performed a WM task on five-tone sequences that were either tonally structured (with all tones belonging to one tonal key) or tonally unstructured (atonal) sequences. Functional differences were observed for musicians (who are experts in the music domain), but not for non-musicians - The right pars orbitalis was activated more strongly in musicians during the encoding of unstructured (atonal) vs. structured (tonal) sequences. In addition, data for musicians showed that a lateral (pre)frontal-parietal network (including the right premotor cortex, right inferior precentral sulcus and left intraparietal sulcus) was activated during WM rehearsal of structured, as compared with unstructured, sequences. Our findings indicate that this network plays a role in strategy-based WM for non-verbal auditory information, corroborating previous results showing a similar network for strategy-based WM for visual and verbal information.


Assuntos
Audição/fisiologia , Memória de Curto Prazo/fisiologia , Música , Desempenho Psicomotor/fisiologia , Estimulação Acústica/métodos , Adulto , Encéfalo/anatomia & histologia , Encéfalo/fisiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Rede Nervosa/anatomia & histologia , Rede Nervosa/fisiologia , Inquéritos e Questionários , Adulto Jovem
6.
Ann N Y Acad Sci ; 1169: 494-8, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19673829

RESUMO

The present study investigated the co-localization of musical and linguistic syntax processing in the human brain. EEGs were recorded from subdural electrodes placed on the left and right perisylvian cortex. The neural generators of the early potentials elicited by syntactic errors in music and language were localized by means of distributed source modeling and compared within subjects. The combined results indicated a partial overlap of the sources within the bilateral superior temporal gyrus, and, to a lesser extent, in the left inferior frontal gyrus, qualifying these areas as shared anatomic substrates of early syntactic error detection in music and language.


Assuntos
Potenciais Evocados/fisiologia , Idioma , Linguística , Música , Semântica , Percepção da Fala/fisiologia , Adulto , Feminino , Humanos , Masculino
7.
Neuroimage ; 31(4): 1771-82, 2006 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-16624581

RESUMO

Neural correlates of the processing of musical syntax-like structures have been investigated via expectancy violation due to musically unrelated (i.e., unexpected) events in musical contexts. Previous studies reported the implication of inferior frontal cortex in musical structure processing. However - due to the strong musical manipulations - activations might be explained by sensory deviance detection or repetition priming. Our present study investigated neural correlates of musical structure processing with subtle musical violations in a musical priming paradigm. Instrumental and sung sequences ended on related and less-related musical targets. The material controlled sensory priming components, and differences in target processing required listeners' knowledge on musical structures. Participants were scanned with functional Magnetic Resonance Imaging (fMRI) while performing speeded phoneme and timbre identification judgments on the targets. Behavioral results acquired in the scanner replicated the facilitation effect of related over less-related targets. The blood oxygen level-dependent (BOLD) signal linked to target processing revealed activation of right inferior frontal areas (i.e., inferior frontal gyrus, frontal operculum, anterior insula) that was stronger for less-related than for related targets, and this was independent of the material carrying the musical structures. This outcome points to the implication of inferior frontal cortex in the processing of syntactic relations also for musical material and to its role in the processing and integration of sequential information over time. In addition to inferior frontal activation, increased activation was observed in orbital gyrus, temporal areas (anterior superior temporal gyrus, posterior superior temporal gyrus and sulcus, posterior middle temporal gyrus) and supramarginal gyrus.


Assuntos
Cognição/fisiologia , Lobo Frontal/fisiologia , Música/psicologia , Adulto , Teorema de Bayes , Córtex Cerebral/fisiologia , Sinais (Psicologia) , Interpretação Estatística de Dados , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Oxigênio/sangue , Desempenho Psicomotor/fisiologia
8.
Vet Immunol Immunopathol ; 100(1-2): 73-80, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15182997

RESUMO

In order to assess age-related differences in feline immune status, 101 domestic short haired cats were assigned to two groups, adult (2-5 years, n=50) and senior (10-14 years, n=51). Analyses of leucocyte populations, lymphocyte subsets, complement activity, serum immunoglobulins and acute-phase proteins were undertaken and revealed significant differences between the two groups. The senior group had significantly lower WBC, lymphocyte and eosinophil counts than the adult group. Neutrophil, monocyte and basophil counts did not differ between the groups. Flow cytometry analysis, in combination with differential WBC data, revealed that the absolute values (cells/l) of T-cells, B-cells and natural killer (NK) cells were significantly lower in the older animals. While serum immunoglobulins IgA and IgM were higher in the senior group when compared with the adult group, no significant differences were observed in complement activity or in serum acute-phase proteins. Our findings suggest that age-related changes to parameters of immune status in the feline model are likely to follow a similar pattern to those observed in other long-lived mammalian species.


Assuntos
Gatos/imunologia , Fatores Etários , Animais , Apolipoproteínas/sangue , Apolipoproteínas/imunologia , Gatos/sangue , Colorimetria/veterinária , Proteínas do Sistema Complemento/imunologia , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Citometria de Fluxo/veterinária , Haptoglobinas/imunologia , Imunodifusão/veterinária , Imunoglobulinas/sangue , Imunoglobulinas/imunologia , Contagem de Leucócitos/veterinária , Subpopulações de Linfócitos/imunologia , Masculino , Proteína Amiloide A Sérica/imunologia , Estatísticas não Paramétricas
10.
Neuroreport ; 12(7): 1385-9, 2001 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-11388416

RESUMO

In the present study, the early right-anterior negativity (ERAN) elicited by harmonically inappropriate chords during listening to music was compared to the frequency mismatch negativity (MMN) and the abstract-feature MMN. Results revealed that the amplitude of the ERAN, in contrast to the MMN, is specifically dependent on the degree of harmonic appropriateness. Thus, the ERAN is correlated with the cognitive processing of complex rule-based information, i.e. with the application of music-syntactic rules. Moreover, results showed that the ERAN, compared to the abstract-feature MMN, had both a longer latency, and a larger amplitude. The combined findings indicate that ERAN and MMN reflect different mechanisms of pre-attentive irregularity detection, and that, although both components have several features in common, the ERAN does not easily fit into the classical MMN framework. The present ERPs thus provide evidence for a differentiation of cognitive processes underlying the fast and pre-attentive processing of auditory information.


Assuntos
Atenção/fisiologia , Percepção Auditiva/fisiologia , Eletroencefalografia/métodos , Potenciais Evocados/fisiologia , Lateralidade Funcional/fisiologia , Música/psicologia , Estimulação Acústica , Adulto , Córtex Auditivo/fisiologia , Mapeamento Encefálico , Feminino , Lobo Frontal/anatomia & histologia , Lobo Frontal/fisiologia , Humanos , Masculino , Tempo de Reação/fisiologia
11.
Nat Neurosci ; 4(5): 540-5, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11319564

RESUMO

The present experiment was designed to localize the neural substrates that process music-syntactic incongruities, using magnetoencephalography (MEG). Electrically, such processing has been proposed to be indicated by early right-anterior negativity (ERAN), which is elicited by harmonically inappropriate chords occurring within a major-minor tonal context. In the present experiment, such chords elicited an early effect, taken as the magnetic equivalent of the ERAN (termed mERAN). The source of mERAN activity was localized in Broca's area and its right-hemisphere homologue, areas involved in syntactic analysis during auditory language comprehension. We find that these areas are also responsible for an analysis of incoming harmonic sequences, indicating that these regions process syntactic information that is less language-specific than previously believed.


Assuntos
Lobo Frontal/fisiologia , Magnetoencefalografia , Processos Mentais/fisiologia , Música/psicologia , Estimulação Acústica , Adulto , Mapeamento Encefálico , Feminino , Lateralidade Funcional/fisiologia , Humanos , Masculino
12.
J Cogn Neurosci ; 12(3): 520-41, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10931776

RESUMO

Only little systematic research has examined event-related brain potentials (ERPs) elicited by the cognitive processing of music. The present study investigated how music processing is influenced by a preceding musical context, affected by the task relevance of unexpected chords, and influenced by the degree and the probability of violation. Four experiments were conducted in which "nonmusicians" listened to chord sequences, which infrequently contained a chord violating the sound expectancy of listeners. Integration of in-key chords into the musical context was reflected as a late negative-frontal deflection in the ERPs. This negative deflection declined towards the end of a chord sequence, reflecting normal buildup of musical context. Brain waves elicited by chords with unexpected notes revealed two ERP effects: an early right-hemispheric preponderant-anterior negativity, which was taken to reflect the violation of sound expectancy; and a late bilateral-frontal negativity. The late negativity was larger compared to in-key chords and taken to reflect the higher degree of integration needed for unexpected chords. The early right-anterior negativity (ERAN) was unaffected by the task relevance of unexpected chords. The amplitudes of both early and late negativities were found to be sensitive to the degree of musical expectancy induced by the preceding harmonic context, and to the probability for deviant acoustic events. The employed experimental design opens a new field for the investigation of music processing. Results strengthen the hypothesis of an implicit musical ability of the human brain.


Assuntos
Percepção Auditiva/fisiologia , Encéfalo/fisiologia , Potenciais Evocados Auditivos/fisiologia , Música , Estimulação Acústica , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Probabilidade
13.
Neuroreport ; 10(6): 1309-13, 1999 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-10363945

RESUMO

The present study focuses on influences of long-term experience on auditory processing, providing the first evidence for pre-attentively superior auditory processing in musicians. This was revealed by the brain's automatic change-detection response, which is reflected electrically as the mismatch negativity (MMN) and generated by the operation of sensoric (echoic) memory, the earliest cognitive memory system. Major chords and single tones were presented to both professional violinists and non-musicians under ignore and attend conditions. Slightly impure chords, presented among perfect major chords elicited a distinct MMN in professional musicians, but not in non-musicians. This demonstrates that compared to non-musicians, musicians are superior in pre-attentively extracting more information out of musically relevant stimuli. Since effects of long-term experience on pre-attentive auditory processing have so far been reported for language-specific phonemes only, results indicate that sensory memory mechanisms can be modulated by training on a more general level.


Assuntos
Atenção/fisiologia , Percepção Auditiva/fisiologia , Potenciais Evocados Auditivos , Música , Estimulação Acústica , Adulto , Análise de Variância , Cognição/fisiologia , Feminino , Audição , Humanos , Masculino , Memória , Ocupações
14.
J Immunol ; 161(9): 4709-18, 1998 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-9794401

RESUMO

IL-4 was found to be the essential differentiation factor for Th2 cells and simultaneously to be a potent inhibitor of Th1 development that is induced by IFN-gamma and IL-12. Furthermore, it was demonstrated that TGF-beta can also inhibit Thl development. In this work, we demonstrate that polyclonal activation of Mel-14highCD4+ T cells by immobilized anti-alphabetaTCR mAb together with a mixture of IL-4 and TGF-beta can lead to the development of both Th1 and Th2 cells, depending on the concentration of these cytokines. Additional experiments revealed that Th1 induction by a combination of IL-4 and TGF-beta depends on the presence of endogenous IFN-gamma, and that this alternative Th1 development is further enhanced by IL-12, but is not dependent on this cytokine. Moreover, naive OVA323-339-specific Th cells that were stimulated by APCs and OVA323-339 peptide differentiated toward Th1 cells after priming in the presence of IL-4 in combination with TGF-beta. Hence, this finding confirmed the results obtained by polyclonal activation of naive CD4+ Th cells and implicates that this alternative Th1 development may also occur in vivo under the influence of TGF-beta and IL-4 independently of the Th1-promoting effect of IL-12.


Assuntos
Interferon gama/fisiologia , Interleucina-12/fisiologia , Interleucina-4/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Células Th1/efeitos dos fármacos , Fator de Crescimento Transformador beta/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , Relação Dose-Resposta Imunológica , Sinergismo Farmacológico , Feminino , Interferon gama/biossíntese , Interleucina-12/farmacologia , Interleucina-4/biossíntese , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Camundongos Endogâmicos DBA , Camundongos Transgênicos , Concentração Osmolar , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Células Th1/citologia , Células Th1/metabolismo , Células Th2/citologia , Células Th2/efeitos dos fármacos
15.
J Immunol ; 157(2): 566-73, 1996 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-8752903

RESUMO

Co-activation of CD4+ T cells by anti-CD4 mAb strongly enhances the proliferation of these T cells. We have analyzed the influence of CD4-mediated co-activation on Th cell differentiation. Our data demonstrate that activation of high density (HD)-CD4+ T cells by immobilized anti-CD3 mAb in combination with immobilized anti-CD4 mAb led to a strong inhibition of Th1 differentiation and to a variable but significant induction of Th2 development. Priming of highly enriched Mel-14highCD4+ T cells in the presence of anti-CD4 mAb also resulted in a pronounced suppression of secondary IFN-gamma production, indicating that the Th1 development of naive CD4+ T cells is inhibited by co-activation via CD4. In contrast to HD-CD4+ T cells, CD4-induced costimulation of MEL-14highCD4+ T cells did not result in a primary and secondary IL-4 production. Hence, these results suggest that a MEL-14low population within the HD-CD4+ T cell fraction was the source of the endogenous IL-4 and imply, in addition, that co-activation via CD4 inhibits the development of Th1 cells from naive CD4+ T cells independently from endogenous IL-4. This assumption is further corroborated by the fact that neither the application of neutralizing anti-IL-4 mAb nor the use of T cells from IL-4 knockout mice could prevent CD4-mediated inhibition of Th1 development. The Th1-inhibiting effect of anti-CD4 mAb could not be reversed by the application of the Th1 inducer IL-12. On the contrary, the secondary IL-4 production of HD-CD4+ T cells as an indicator of Th2 differentiation, which was promoted by anti-CD4 mAb, was enhanced even in the presence of IL-12. Therefore, our results suggest that co-activation of naive CD4+ T cells by anti-CD4 mAb directly and selectively inhibits Th1 differentiation of naive dense CD4+ T cells.


Assuntos
Anticorpos Monoclonais/farmacologia , Antígenos CD4/imunologia , Linfócitos T CD4-Positivos/imunologia , Inibidores do Crescimento/imunologia , Ativação Linfocitária , Células Th1/imunologia , Animais , Complexo CD3/imunologia , Contagem de Linfócito CD4 , Diferenciação Celular/imunologia , Sinergismo Farmacológico , Feminino , Inibidores do Crescimento/farmacologia , Imunofenotipagem , Imunossupressores/farmacologia , Interferon gama/antagonistas & inibidores , Interferon gama/biossíntese , Interleucina-12/farmacologia , Interleucina-4/fisiologia , Ativação Linfocitária/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Camundongos Mutantes
16.
Immunobiology ; 196(5): 475-84, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9145325

RESUMO

Cytokines were found to play a key role in Th cell differentiation. Among them IL-12 was shown to be a potent differentiation factor for Th1 cells, whereas IL-4 is the only known cytokine that promotes the development of Th2 cells. Upon addition of comparable amounts of IL-4 and IL-12 to a primary culture of naive CD4+ T cells activated by immobilized anti-CD3 mAb, it was found that the Th1-inducing capacity of IL-12 is dominated by the Th2-promoting effect of IL-4. However, high amounts of IL-12 (10,000 U/ml) in combination with low amounts of IL-4 (100 U/ml) led to the development of a Th cell population that, upon rechallenge, showed a substantial secondary IFN-gamma (Th1 cytokine) production concomitantly with the production of high amounts of IL-4 (Th2 cytokine). This can be due to the coexistence of Th1 and Th2 cells or to the development of Th0 cells producing a mixed pattern of cytokines. Immunofluorescence double staining of intracellular IL-4 and IFN-gamma in combination with flow cytometry (FACS) revealed that most of the emerging Th cells produced either IL-4 or IFN-gamma. Only a few double producers could be detected. This finding indicates that individual naive CD4+ T cells can differentiate under the same conditions towards Th1 or Th2 cells and implicates that the development of Th1 and Th2 cells is not necessarily mutually exclusive.


Assuntos
Linfócitos T CD4-Positivos/citologia , Interleucina-12/farmacologia , Interleucina-4/farmacologia , Células Th1/citologia , Células Th2/citologia , Animais , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/metabolismo , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/imunologia , Células Cultivadas , Combinação de Medicamentos , Feminino , Interferon gama/biossíntese , Interleucina-12/biossíntese , Interleucina-12/imunologia , Interleucina-4/biossíntese , Interleucina-4/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos CBA , Camundongos Endogâmicos DBA , Células Th1/efeitos dos fármacos , Células Th1/metabolismo , Células Th2/efeitos dos fármacos , Células Th2/imunologia
17.
J Immunol ; 155(8): 3788-93, 1995 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-7561083

RESUMO

The development of naive dense CD4+ T cells from different mouse strains toward Th1 cells, as monitored by measuring secondary IFN-gamma production, was affected by TGF-beta 2 in a differential way. Th1 cell development of naive CD4+ T cells from strains C57Bl/6, BALB/c, and NMRI primed by immobilized anti-CD3 mAb was strongly inhibited in the presence of TGF-beta 2. Even when the Th1 cell-inducer IL-12 was added, the same effect of TGF-beta 2 was observed. In contrast, Th1 development was substantially promoted by TGF-beta 2 with T cells from C3H/He and CBA/J mice. Further analyses using CD4+ T cells from (C57Bl/6xCBA/J)F1 hybrids or DBA/1 mice showed that Th1 development was inhibited by TGF-beta 2 if the T cells were activated by anti-CD3 mAb, but it was enhanced upon costimulation with anti-CD28 mAb. Determination of primary IL-2 production revealed that T cells from (C57Bl/6xCBA/J)F1 and DBA/1 mice produced low amounts of IL-2 following stimulation by anti-CD3 mAb alone and comparatively high amounts after coactivation by anti-CD28 mAb. In the presence of TGF-beta 2, the production of IL-2 was completely suppressed if such T cells were activated solely by anti-CD3 mAb, but it was only partially inhibited after costimulation by anti-CD28 mAb. Furthermore, TGF-beta 2-promoted Th1 development of such T cells was strongly inhibited after neutralization of endogenously produced IL-2 and completely restored by the addition of human IL-2. Thus, our results indicate that the TGF-beta 2-mediated stimulation of Th1 cell development requires the presence of relatively high concentrations of IL-2. Therefore, the opposing effect of TGF-beta 2 on the Th1 cell development of naive CD4+ T cells from different mouse strains appears to be the result of the variable potency of the respective CD4+ T cells to produce IL-2 in the presence of TGF-beta 2.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Células Th1/imunologia , Fator de Crescimento Transformador beta/fisiologia , Animais , Diferenciação Celular/imunologia , Separação Celular , Células Cultivadas , Feminino , Humanos , Interleucina-2/biossíntese , Interleucina-2/metabolismo , Interleucina-2/fisiologia , Ativação Linfocitária , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Camundongos Endogâmicos DBA
18.
Int Immunol ; 7(4): 525-32, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7547678

RESUMO

Activation of naive dense CD4+ T cells by plate-bound anti-CD3 antibodies favors the development of Th1 cells which, upon re-stimulation, produce significant amounts of IFN-gamma but no IL-4. However, co-activation of such naive T cells in the presence of IgE [anti-dinitrophenyl (DNP)]-loaded bone marrow-derived mast cells (BMMC) on plates coated with anti-CD3 antibodies and DNP-BSA led to the development of IL-4-producing Th2 cells. The same result could be observed if irradiated (800 rad) BMMC were applied as co-stimulators. Moreover, BMMC could be replaced by the supernatant of IgE-activated BMMC suggesting that a soluble mediator, presumably IL-4, was responsible for this effect. This assumption was substantiated using neutralizing anti-IL-4 antibodies which abolished the BMMC-mediated Th2 development in all cases. Addition of IL-12, a cytokine that was shown to antagonize the Th2-promoting effect of IL-4 in vivo, could not inhibit the development of IL-4-producing T cells, but gave rise to a T cell population which produced relatively high amounts of IL-4 and IFN-gamma. Since BMMC represent the in vitro equivalent of mucosal mast cells these data suggest that IgE-activated mucosal mast cells can bias an emerging T cell dependent immune response towards a Th2 dominated reaction by the initial production of IL-4.


Assuntos
Linfócitos T CD4-Positivos/fisiologia , Interleucina-4/fisiologia , Ativação Linfocitária , Mastócitos/fisiologia , Células Th2/imunologia , Animais , Células da Medula Óssea , Complexo CD3/imunologia , Células Cultivadas , Citocinas/biossíntese , Feminino , Interleucina-4/biossíntese , Ionomicina/farmacologia , Masculino , Mastócitos/citologia , Camundongos , Camundongos Endogâmicos BALB C , Receptores de IgE/fisiologia
19.
J Immunol ; 153(9): 3989-96, 1994 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-7930607

RESUMO

Dense CD4+ T cells isolated from naive mice produce only trace amounts of IL-9 when stimulated by immobilized anti-CD3 in combination with anti-CD28 Abs. In this situation, IL-9 production is significantly stimulated by TGF-beta and further enhanced by the addition of IL-4, which, by itself, has only a minimal influence. IFN-gamma was found to inhibit the enhancing effect of IL-4. However, increasing amounts of IL-4 in the presence of a constant concentration of IFN-gamma could overcome the inhibitory activity of IFN-gamma. The application of CD4+ T cells isolated from IL-2 knockout mice unequivocally revealed that IL-2 is essential for the production of IL-9 by T cells. In addition, the use of T cells from IL-4 knockout mice elucidated that the basic (IL-2 + TGF-beta) mediated IL-9 production is independent of IL-4. Therefore, our results demonstrate that optimal IL-9 production of naive dense CD4+ T cells is positively regulated at different levels: 1) by IL-2, which is essential for IL-9 secretion; 2) followed by TGF-beta, which promotes a considerable increase in IL-9 production above the level induced by IL-2; and 3) finally, by IL-4, which requires the presence of IL-2 and TGF-beta to strongly enhance the production of IL-9. IFN-gamma inhibits the production of IL-9 mainly at the level of IL-4 by neutralizing the effect of this cytokine.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Citocinas/fisiologia , Interleucina-9/biossíntese , Animais , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Feminino , Interferon gama/fisiologia , Interleucina-2/fisiologia , Interleucina-4/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Fator de Crescimento Transformador beta/fisiologia
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