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2.
Nat Med ; 2(2): 216-23, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8574968

RESUMO

The introduction and expression of genes in somatic cells is an innovative therapy for correcting genetic deficiency diseases and augmenting immune function. A potential obstacle to gene therapy is the elimination of such gene-modified cells by an immune response to novel protein products of the introduced genes. We are conducting an immunotherapy trial in which individuals seropositive for human immunodeficiency virus (HIV) receive CD8+ HIV-specific cytotoxic T cells modified by retroviral transduction to express a gene permitting positive and negative selection. However, five of six subjects developed cytotoxic T-lymphocyte responses specific for the novel protein and eliminated the transduced cytotoxic T cells. The rejection of genetically modified cells by these immunocompromised hosts suggests that strategies to render gene-modified cells less susceptible to host immune surveillance will be required for successful gene therapy of immunocompetent hosts.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Citotoxicidade Imunológica , Antígenos HIV/imunologia , Infecções por HIV/terapia , Imunoterapia Adotiva , Apresentação de Antígeno , Sequência de Bases , Linfócitos T CD8-Positivos/transplante , Infecções por HIV/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Dados de Sequência Molecular
3.
Curr Opin Immunol ; 5(4): 484-91, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8216922

RESUMO

The development of CD8+ cytotoxic T cell responses to viral pathogens is crucial for the prompt resolution of acute infections and for the control of viruses which persist in the host. Thus, cytomegalovirus often causes life threatening disease in immunosuppressed humans who fail to develop or maintain CD8+ cytotoxic T cells. Similarly, the loss of CD8+ cytotoxic T cell responses to HIV correlates with the development of AIDS. Recent investigations in the immunobiology of cytomegalovirus and HIV have resulted in the application of immunotherapeutic strategies designed to reconstitute or augment deficient CD8+ cytotoxic T cell responses to these human pathogens.


Assuntos
Infecções por Citomegalovirus/terapia , Infecções por HIV/terapia , Imunoterapia Adotiva , Linfócitos T Citotóxicos/imunologia , Linfócitos T Reguladores/imunologia , Síndrome da Imunodeficiência Adquirida/imunologia , Síndrome da Imunodeficiência Adquirida/terapia , Animais , Infecções por Citomegalovirus/imunologia , Modelos Animais de Doenças , Infecções por HIV/imunologia , Humanos , Imunidade , Camundongos
4.
AIDS ; 14(4): 387-95, 2000 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-10770541

RESUMO

OBJECTIVE: To evaluate the effect of adjuvant granulocyte-macrophage colony-stimulating factor (GM-CSF) (sargramostim, yeast-derived recombinant human GM-CSF) on incidence and time to opportunistic infection or death, plasma HIV-RNA, and CD4 cell count in patients with advanced HIV disease. METHODS: This Phase III randomized, double-blind, placebo-controlled trial enrolled subjects with CD4 cell counts < or = 50 x 10(6)/l or < or = 100 x 10(6)/l with a prior AIDS-defining illness on stable antiretroviral therapy. Subjects were stratified by baseline HIV-RNA level (> or = or < 30,000 copies/ml) and randomized to receive subcutaneous injections of GM-CSF 250 microg or placebo three times per week for 24 weeks. Subjects were permitted to continue on blinded drug for up to 20 months. Subjects were evaluated for infections, plasma HIV-RNA, lymphocyte counts, changes in antiretroviral therapy, toxicity, and survival. RESULTS: Three-hundred and nine subjects received at least one dose of study drug, 70% completed 24 weeks of therapy. Groups were well matched at baseline. Significant increases in CD4 cell and neutrophil counts were observed at 1, 3, and 6 months in the GM-CSF group. GM-CSF significantly reduced the incidence of overall infections (78% placebo versus 67% GM-CSF; P = 0.03) and delayed time to first infection (56 days placebo versus 97 days GM-CSF; P = 0.04). No statistical difference in cumulative opportunistic infections was observed between groups; however, among subjects without an opportunistic infection prior to study, the GM-CSF group demonstrated a trend towards fewer subjects with an opportunistic infection on study (26% placebo versus 8% GM-CSF; P = 0.08). Change in HIV-RNA was not significantly different between groups, but significantly fewer GM-CSF subjects with baseline viral load < 30,000 copies/ml had changes in antiretroviral therapy for increased viral load (42% placebo versus 21% GM-CSF; P = 0.01). In patients with HIV-RNA levels below the limit of detection at baseline, more GM-CSF patients maintained an undetectable viral load at 24 weeks (54% placebo versus 83% GM-CSF; P = 0.02). GM-CSF was well tolerated. CONCLUSIONS: GM-CSF significantly increased CD4 cell count and decreased virological breakthrough and overall infection rate in subjects with advanced HIV disease.


Assuntos
Contagem de Linfócito CD4 , Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Infecções por HIV/tratamento farmacológico , Carga Viral , Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Infecções Oportunistas Relacionadas com a AIDS/prevenção & controle , Adulto , Idoso , Método Duplo-Cego , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/efeitos adversos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Placebos , Proteínas Recombinantes
5.
Br J Pharmacol ; 102(3): 615-20, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1364827

RESUMO

1. Using grease-gap recordings from the isolated superior cervical ganglion of mouse, rat and guinea-pig, we have compared the depolarization evoked by 5-hydroxytryptamine (5-HT) with that evoked by the selective 5-HT3 receptor agonist 2-methyl-5-HT (2-Me-5-HT). 2. The maximum depolarization induced by 2-Me-5-HT was smaller than that induced by 5-HT in all three species, and particularly in the guinea-pig. 3. The 5-HT2 receptor antagonist ketanserin (1 microM) caused a clear rightward shift of the dose-response curve to 5-HT on the guinea-pig ganglion, but not on the mouse or rat ganglion. Spiperone (0.03 microM) had a quantitatively similar action to ketanserin (0.1 microM) on the 5-HT dose-response curve of the guinea-pig ganglion. Ketanserin had no significant effect on the dose-response curve to 2-Me-5-HT on any of these ganglia. 4. Using 2-Me-5-HT as the agonist, we determined the pA2 values for two 5-HT3 receptor antagonists. The potency of ICS 205-930 varied by approximately 100 fold between the species and that of (+)-tubocurarine varied by over 1000 fold. The differences in the pA2 values of these compounds varied independently among the species. 5. We conclude that 5-HT3 receptors are present on the superior cervical ganglion from the rat, mouse and guinea-pig, but these receptors may be pharmacologically distinct from each other. In addition, the depolarization of the guinea-pig superior cervical ganglion by low concentrations of 5-HT is largely mediated by ketanserin-sensitive receptors.


Assuntos
Receptores de Serotonina/efeitos dos fármacos , Gânglio Cervical Superior/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Cobaias , Indóis/farmacologia , Ketanserina/farmacologia , Masculino , Camundongos , Ratos , Ratos Sprague-Dawley , Receptores de Serotonina/fisiologia , Serotonina/análogos & derivados , Serotonina/farmacologia , Gânglio Cervical Superior/fisiologia , Tropizetrona , Tubocurarina/farmacologia
6.
Br J Pharmacol ; 101(3): 575-80, 1990 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2076477

RESUMO

1 A novel series of non-quaternary oxadiazole-based muscarinic agonists demonstrated high affinity for muscarinic receptors. 2. These agonists possessed high efficacy in the nanomolar range at muscarinic receptors in the superior cervical ganglion, atrium and ileum but did not show selectivity across the tissue preparations. 3. Two amino oxadiazoles, one from a quinuclidine series (L-660,863) and one from a 1-azanorbornane series (L-670,207) possessed a high ratio of potency for displacing the binding of [3H]-N-methyl-scopolamine ([3H]-NMS) to potency for displacing the agonist [3H]-oxotremorine-M cortex. 4. The two azanorbornane derivatives L-670,548 and L-670,207 stimulated the turnover of phosphatidylinositol in the cortex with a potency higher than that obtained with any other known muscarinic agonist (ED50 0.26 and 0.18 microM respectively). 5. The maximum response obtained with L-670,207 was greater than that observed for carbachol but was comparable to that of the natural ligand acetylcholine. 6. These oxadiazole muscarinic agonists are among the most potent and efficacious non-quaternary muscarinic agonists ever described.


Assuntos
Oxidiazóis/farmacologia , Parassimpatomiméticos , Receptores Muscarínicos/efeitos dos fármacos , Animais , Ligação Competitiva , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Gânglios Simpáticos/efeitos dos fármacos , Gânglios Simpáticos/metabolismo , Cobaias , Átrios do Coração/efeitos dos fármacos , Átrios do Coração/metabolismo , Íleo/efeitos dos fármacos , Íleo/metabolismo , Técnicas In Vitro , Masculino , Oxidiazóis/química , Oxidiazóis/metabolismo , Fosfatidilinositóis/metabolismo , Ratos , Receptores Muscarínicos/metabolismo , Relação Estrutura-Atividade
7.
Bone Marrow Transplant ; 14 Suppl 4: S78-84, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7728132

RESUMO

The adoptive transfer of T cells specific for antigens encoded by pathogens and tumors has been an effective treatment for infections and malignancies in animal models and is potentially applicable for infections occurring in immunodeficient bone marrow transplant recipients. This article reviews recent insights derived from studies of the immunobiology of human cytomegalovirus (CMV) infection in healthy and immunodeficient hosts and the development of adoptive immunotherapy as prophylaxis for CMV infection in recipients of allogeneic bone marrow transplants.


Assuntos
Transplante de Medula Óssea , Infecções por Citomegalovirus/prevenção & controle , Imunoterapia Adotiva , Linfócitos T Citotóxicos/transplante , Animais , Antígenos Virais/imunologia , Transplante de Medula Óssea/efeitos adversos , Células Cultivadas/transplante , Citomegalovirus/imunologia , Infecções por Citomegalovirus/etiologia , Infecções por Citomegalovirus/imunologia , Infecções por Citomegalovirus/terapia , Infecções por Citomegalovirus/transmissão , Humanos , Proteínas Imediatamente Precoces/imunologia , Imunocompetência , Hospedeiro Imunocomprometido , Epitopos Imunodominantes/imunologia , Linfopenia/complicações , Linfopenia/terapia , Camundongos , Camundongos Endogâmicos BALB C , Linfócitos T Citotóxicos/imunologia , Proteínas Estruturais Virais/imunologia
8.
Eur J Pharmacol ; 162(2): 197-205, 1989 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-2721566

RESUMO

In addition to the 5-HT3-mediated fast depolarisation, 5-hydroxytryptamine (5-HT) evoked two additional responses on the rat superior cervical ganglion: a hyperpolarisation and a slow depolarisation. These responses appeared to be direct actions on 5-HT receptors since they were present in a low calcium medium containing tetrodotoxin and were not abolished by a variety of non-serotonin antagonists. The hyperpolarisation was not antagonised by 5-HT3 or 5-HT2 antagonists. The 5-HT1 ligands 5-carboxamidotryptamine (5-CT) and 8-OH-DPAT also evoked a hyperpolarisation. The hyperpolarisation was antagonised by six 5-HT1A antagonists including WB-4101 and spiroxatrine. It was therefore concluded to be mediated by a 5-HT1A receptor. The slow depolarisation was only evoked by 5-HT. The receptor involved in this response, however, could not be determined. We conclude that in addition to 5-HT3 receptors the rat superior cervical ganglion possesses 5-HT1A receptors and another uncharacterised 5-HT receptor.


Assuntos
Gânglios Espinais/efeitos dos fármacos , Serotonina/farmacologia , Animais , Técnicas In Vitro , Masculino , Fármacos Neuromusculares Despolarizantes/farmacologia , Ratos , Ratos Endogâmicos , Antagonistas da Serotonina/farmacologia
9.
Eur J Pharmacol ; 163(2-3): 237-44, 1989 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-2721572

RESUMO

The dose-response curve for the muscarine-induced depolarisation of the rat isolated superior cervical ganglion, studied over the concentration range of 3 nM-1 mM, was biphasic. An apparent maximum was obtained at around 1-3 microM muscarine, but this was only a plateau between the two parts of the curve. Two cardioselective antagonists, gallamine (10 microM) and AF-DX 116 (1 microM) had a complex action on this dose-response curve. The dose-response curve between 0.01 and 0.3 microM was shifted to the right, the responses around 3 microM muscarine were enhanced, but the dose-response curve over 30 microM muscarine was unaffected. The M1-selective antagonist pirenzepine (0.05 microM) depressed all parts of the dose-response curve, but it still appeared biphasic. Pretreatment of the ganglion with pertussis toxin (1 microgram/ml) enhanced the depolarisation to muscarine 0.01-1000 microM and the dose-response curve became less biphasic. Like gallamine and AF-DX 116, pertussis toxin abolished the muscarinic M2-mediated hyperpolarisation of the ganglion recorded in 0.3 microM pirenzepine. It is concluded that the presence of an underlying M2-mediated hyperpolarisation contributes to the biphasic nature of the dose-response curve to muscarine.


Assuntos
Gânglios Espinais/efeitos dos fármacos , Muscarina/farmacologia , Animais , Relação Dose-Resposta a Droga , Trietiodeto de Galamina/farmacologia , Técnicas In Vitro , Toxina Pertussis , Pirenzepina/análogos & derivados , Pirenzepina/farmacologia , Ratos , Fatores de Virulência de Bordetella/farmacologia
10.
Eur J Pharmacol ; 163(2-3): 245-52, 1989 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-2721573

RESUMO

We have investigated the action of pertussis toxin on a range of receptor-mediated responses of the rat superior cervical ganglion in vitro. The ganglia were treated with pertussis toxin for 24 h at 37 degrees C using an in vitro method. Appropriate controls were also carried out. Pertussis toxin (1 microgram/ml) reduced ganglionic hyperpolarisations mediated by adenosine, alpha 2, 5-HT1A, M2 and GABAB receptors. The GABAB-mediated hyperpolarisation of this preparation, evoked by baclofen and GABA in a bicuculline-resistant manner, has not previously been reported. Pertussis toxin did not reduce ganglionic depolarisations evoked by potassium chloride and 5-HT3, GABAA and nicotinic receptors. Depolarisations to muscarine and noradrenaline, probably mediated by M1 and beta-receptors, also appeared to be resistant to pertussis toxin. The similar sensitivity of the various ganglionic hyperpolarisations to pertussis toxin indicates that they may all be mediated by similar G-proteins.


Assuntos
Gânglios Espinais/efeitos dos fármacos , Toxina Pertussis , Fatores de Virulência de Bordetella/farmacologia , Animais , Interações Medicamentosas , Potenciais Evocados/efeitos dos fármacos , Ratos , Fatores de Virulência de Bordetella/antagonistas & inibidores
11.
Eur J Pharmacol ; 144(3): 385-8, 1987 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-2964375

RESUMO

5-HT induced a hyperpolarization of the rat superior cervical ganglion in vitro which was resistant to both MDL 72222 (10 microM), a 5-HT3 antagonist, and ketanserin (1 microM), a 5-HT2 antagonist. The 5-HT1-selective ligands 5-carboxamidotryptamine and 8-OH-DPAT also hyperpolarized the ganglion. The 5-HT-induced hyperpolarization was potently antagonised by spiperone. These results suggest that 5-HT hyperpolarizes the rat superior cervical ganglion via a 5-HT1-like receptor which resembles the central 5-HT1A binding site.


Assuntos
Gânglios Simpáticos/fisiologia , Receptores de Serotonina/fisiologia , 8-Hidroxi-2-(di-n-propilamino)tetralina , Animais , Gânglios Simpáticos/efeitos dos fármacos , Técnicas In Vitro , Ketanserina/farmacologia , Potenciais da Membrana/efeitos dos fármacos , Ratos , Receptores de Serotonina/efeitos dos fármacos , Serotonina/análogos & derivados , Serotonina/farmacologia , Antagonistas da Serotonina/farmacologia , Tetra-Hidronaftalenos/farmacologia , Tropanos/farmacologia
12.
Eur J Pharmacol ; 167(3): 411-4, 1989 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-2806379

RESUMO

We have determined the antagonist affinity of hexahydrodifenidol in a range of receptor assays in the rat:-radioreceptor binding and phosphatidyl-inositol turnover assays in cerebral cortex and hippocampus, and electrophysiological experiments on the superior cervical ganglion and hippocampus. We failed to detect any appreciable differences in the affinity of hexahydrodifenidol among any of these assays.


Assuntos
Córtex Cerebral/metabolismo , Gânglios Simpáticos/metabolismo , Hipocampo/metabolismo , Piperidinas/farmacologia , Receptores Muscarínicos/efeitos dos fármacos , Animais , Córtex Cerebral/efeitos dos fármacos , Eletrofisiologia , Gânglios Simpáticos/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Técnicas In Vitro , Masculino , Pirenzepina/farmacologia , Ratos , Ratos Endogâmicos
13.
J Phys Condens Matter ; 24(35): 355301, 2012 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-22885555

RESUMO

We study the effects of disorder on the interlayer transport properties of disordered semiconductor bilayers by performing self-consistent quantum transport calculations. We find that the addition of material disorder to the system affects the interlayer interactions leading to significant deviations in the interlayer transfer characteristics. In particular, we find that disorder decreases and broadens the tunneling peak, effectively reducing the interacting system to a non-interacting system. Our results suggest that the experimental observation of exchange-enhanced interlayer transport in semiconductor bilayers requires materials with mean free paths larger than the spatial extent of the system.

14.
J Phys Condens Matter ; 23(34): 345302, 2011 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-21841235

RESUMO

We investigate the superfluid properties of disordered double layer graphene systems using the non-equilibrium Green's function formalism. The complexity of such a structure makes it imperative to study the effects of lattice vacancies which will inevitably arise during fabrication. We present and compare room temperature performance characteristics for both ideal and disordered double layer graphene systems in an effort to illustrate the behavior of a Bose-Einstein condensate in the presence of lattice defects under non-equilibrium conditions. We find that lattice vacancies spread throughout the top layer past the coherence length have a reduced effect compared to the ideal case. However, vacancies concentrated near the metal contacts within the coherence length significantly alter the interlayer superfluid transport properties.

15.
J Phys Condens Matter ; 22(14): 145301, 2010 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-21389524

RESUMO

We explore exchange coupling of a pair of spins in a double dot and in an optical lattice, using the frequency of exchanges in a bosonic path integral, evaluated using Monte Carlo simulation. The algorithm gives insights into the role of correlation through visualization of two-particle probability densities, instantons, and the correlation hole. We map the problem to the Hubbard model and see that exchange and correlation renormalize the model parameters, dramatically reducing the effective on-site repulsion at larger separations.

18.
Int J Addict ; 25(2A): 127-47; discussion 147-8, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2269550

RESUMO

As research disciplines differ from each other in terms of their epistemological and theoretical assumptions, they differ in the kinds of data they produce. This paper discusses the particular perspectives and methods that anthropologically produced data contribute to a biopsychosocial paradigm of alcohol use/pathology. Strategic uses of qualitative research approaches are suggested, and situations in which qualitatively produced data would be especially useful in the design and delivery of alcohol-related services are identified.


Assuntos
Alcoolismo/prevenção & controle , Antropologia , Consumo de Bebidas Alcoólicas , Alcoolismo/etiologia , Alcoolismo/psicologia , Antropologia/métodos , Coleta de Dados/métodos , Humanos , Projetos de Pesquisa
19.
Clin Immunol Immunopathol ; 86(1): 115-9, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9434804

RESUMO

Graft-versus-host disease (GVHD) is a major complication associated with allogeneic bone marrow transplantation (BMT). Cyclosporin A (CsA) has been used as the basis for most immunosuppressive regimens for the prevention of GVHD, but has exhibited only limited effects and is hampered by nephrotoxicity, neurotoxicity, and hepatotoxicity. Previously, we showed that rD-mPGPtide, a structure-base designed peptide analog of the CDR3-like region of domain 1 of the murine CD4 molecule, suppressed the development of GVHD in a MHC-haploidentical murine BMT model when administered early in the course of disease. This peptide analog also inhibited T cell proliferation in mixed lymphocyte reactions (MLR) in vitro. The current results demonstrate that CsA and rD-mPGPtide exhibit an additive inhibitory effect on MLR. Furthermore, the use of CsA and rD-mPGPtide together for prevention of GVHD nearly doubled the median survival time of the mice compared to either agent alone. In addition, the combination therapy reduced the requirement for habitual administration of CsA. Therefore, the use of a CD4-CDR3 peptide can complement and potentiate the immunosuppressive effects of CsA in the prevention of GVHD following allogeneic BMT.


Assuntos
Transplante de Medula Óssea/efeitos adversos , Ciclosporina/uso terapêutico , Doença Enxerto-Hospedeiro/prevenção & controle , Imunossupressores/uso terapêutico , Oligopeptídeos/uso terapêutico , Transplante Homólogo/efeitos adversos , Animais , Ciclosporina/administração & dosagem , Avaliação Pré-Clínica de Medicamentos , Sinergismo Farmacológico , Quimioterapia Combinada , Doença Enxerto-Hospedeiro/etiologia , Imunossupressores/administração & dosagem , Teste de Cultura Mista de Linfócitos , Masculino , Camundongos
20.
Int J Addict ; 29(9): 1127-47, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7960309

RESUMO

The article explores alcohol expectations among Mexican-American women utilizing the Alcohol Expectancy Questionnaire and a series of quantity/frequency alcohol use measures. The results indicate that Mexican-American women generally have similar expectations about the benefits of alcohol use as women in the larger population. Within the sample of Mexican-American women however, there were differences in alcohol expectations based on occupational status and acculturation level: those Mexican-American women who are more acculturated and hold higher professional status occupations have higher expectations of the benefits of alcohol use than less acculturated Mexican-American women in blue-collar or service occupations.


Assuntos
Consumo de Bebidas Alcoólicas/psicologia , Americanos Mexicanos/psicologia , Enquadramento Psicológico , População Urbana , Aculturação , Adolescente , Adulto , Consumo de Bebidas Alcoólicas/epidemiologia , Estudos Transversais , Feminino , Identidade de Gênero , Humanos , Incidência , Los Angeles/epidemiologia , Americanos Mexicanos/estatística & dados numéricos , Pessoa de Meia-Idade , Comportamento Social , Fatores Socioeconômicos , População Urbana/estatística & dados numéricos
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