Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
JAMA Netw Open ; 7(4): e248051, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38652471

RESUMO

Importance: There is still considerable controversy in the literature regarding the capacity of intramuscular messenger RNA (mRNA) vaccination to induce a mucosal immune response. Objective: To compare serum and salivary IgG and IgA levels among mRNA-vaccinated individuals with or without previous SARS-CoV-2 infection. Design, Setting, and Participants: In this cohort study, SARS-CoV-2-naive participants and those with previous infection were consecutively included in the CoviCompare P and CoviCompare M mRNA vaccination trials and followed up to day 180 after vaccination with either the BNT162b2 (Pfizer-BioNTech) vaccine or the mRNA-1273 (Moderna) vaccine at the beginning of the COVID-19 vaccination campaign (from February 19 to June 8, 2021) in France. Data were analyzed from October 25, 2022, to July 13, 2023. Main Outcomes and Measures: An ultrasensitive digital enzyme-linked immunosorbent assay was used for the comparison of SARS-CoV-2 spike-specific serum and salivary IgG and IgA levels. Spike-specific secretory IgA level was also quantified at selected times. Results: A total of 427 individuals were included in 3 groups: participants with SARS-CoV-2 prior to vaccination who received 1 single dose of BNT162b2 (Pfizer-BioNTech) (n = 120) and SARS-CoV-2-naive individuals who received 2 doses of mRNA-1273 (Moderna) (n = 172) or 2 doses of BNT162b2 (Pfizer-BioNTech) (n = 135). The median age was 68 (IQR, 39-75) years, and 228 (53.4%) were men. SARS-CoV-2 spike-specific IgG saliva levels increased after 1 or 2 vaccine injections in individuals with previous infection and SARS-CoV-2-naive individuals. After vaccination, SARS-CoV-2-specific saliva IgA levels, normalized with respect to total IgA levels, were significantly higher in participants with previous infection, as compared with the most responsive mRNA-1273 (Moderna) recipients (median normalized levels, 155 × 10-5 vs 37 × 10-5 at day 29; 107 × 10-5 vs 54 × 10-5 at day 57; and 104 × 10-5 vs 70 × 10-5 at day 180 [P < .001]). In contrast, compared with day 1, spike-specific IgA levels in the BNT162b2-vaccinated SARS-CoV-2-naive group increased only at day 57 (36 × 10-5 vs 49 × 10-5 [P = .01]). Bona fide multimeric secretory IgA levels were significantly higher in individuals with previous infection compared with SARS-CoV-2-naive individuals after 2 antigenic stimulations (median optical density, 0.36 [IQR, 0.16-0.63] vs 0.16 [IQR, 0.10-0.22]; P < .001). Conclusions and Relevance: The findings of this cohort study suggest that mRNA vaccination was associated with mucosal immunity in individuals without prior SARS-CoV-2 infection, but at much lower levels than in previously infected individuals. Further studies are needed to determine the association between specific saliva IgA levels and prevention of infection or transmission.


Assuntos
Vacina de mRNA-1273 contra 2019-nCoV , Anticorpos Antivirais , Vacina BNT162 , Vacinas contra COVID-19 , COVID-19 , Imunoglobulina A , Imunoglobulina G , SARS-CoV-2 , Saliva , Humanos , Masculino , Imunoglobulina G/sangue , Feminino , COVID-19/prevenção & controle , COVID-19/imunologia , SARS-CoV-2/imunologia , Saliva/imunologia , Pessoa de Meia-Idade , Adulto , Imunoglobulina A/análise , Imunoglobulina A/sangue , Anticorpos Antivirais/análise , Anticorpos Antivirais/sangue , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/administração & dosagem , Vacinação/métodos , Estudos de Coortes , Idoso , Imunidade nas Mucosas/imunologia , França
2.
Int J Stroke ; 19(3): 367-372, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37740419

RESUMO

RATIONALE: Mechanical thrombectomy (MT) associated with the best medical treatment (BMT) has recently shown efficacy for the management of acute ischemic stroke (AIS) secondary to a large vessel occlusion. However, evidence is lacking regarding the benefit of MT for more distal occlusions. AIM: To evaluate the efficacy in terms of good clinical outcome at 3 months of MT associated with the BMT over the BMT alone in AIS related to a distal occlusion. METHODS: The DISCOUNT trial is a multicenter open-label randomized controlled trial involving French University hospitals. Adult patients (⩾18 years) with an AIS involving the anterior or posterior circulation secondary to a distal vessel occlusion within 6 h of symptom onset or within 24 h if no hyperintense signal on fluid attenuation inversion recovery acquisition will be randomized 1:1 to receive either MT associated with the BMT (experimental group) or BMT alone (control group). The number of patients to be included is 488. STUDY OUTCOMES: The primary outcome is the rate of good clinical outcome at 3 months defined as a modified Rankin scale (mRS) ⩽2 and evaluated by an independent assessor blinded to the intervention arm. Secondary outcomes include recanalization of the occluded vessel within 48 h, angiographic reperfusion in the experimental group, 3-month excellent clinical outcome (mRS ⩽ 1), all adverse events, and death. A cost utility analysis will estimate the incremental cost per quality-adjusted life year (QALY) gained. DISCUSSION: If positive, this study will open new insights in the management of AISs. TRIAL REGISTRATION: ClinicalTrials.gov: NCT05030142 registered on 1 September 2021.


Assuntos
Arteriopatias Oclusivas , Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Adulto , Humanos , AVC Isquêmico/complicações , Acidente Vascular Cerebral/tratamento farmacológico , Resultado do Tratamento , Trombectomia , Arteriopatias Oclusivas/terapia , Arteriopatias Oclusivas/complicações , Isquemia Encefálica/terapia , Isquemia Encefálica/complicações
3.
Sci Rep ; 12(1): 20373, 2022 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-36437298

RESUMO

Immune response induced by COVID-19 vaccine booster against delta and omicron variants was assessed in 65 adults (65-84 years old) early aftesr a first booster dose. An increase in SARS-CoV-2 neutralizing antibodies was shown in individuals not previously infected without evidence of an age-related effect, with lower increase in those infected before a single dose of primary vaccination. Of note, humoral response was observed only starting from the 5th day after the boost.


Assuntos
COVID-19 , Vacinas Virais , Humanos , Idoso , Idoso de 80 Anos ou mais , Anticorpos Neutralizantes , SARS-CoV-2/genética , Testes de Neutralização , Anticorpos Antivirais , RNA Mensageiro , COVID-19/prevenção & controle , Vacinação
5.
BMC Cancer ; 14: 427, 2014 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-24923533

RESUMO

BACKGROUND: Survival is poorer in elderly patients with head and neck squamous cell carcinomas [HNSCCs] than in younger patients. Possible explanations include a contribution of co-morbidities to mortality, frequent refusal of standard therapy, and the use of suboptimal treatments due to concern about toxicities. The Comprehensive Geriatric Assessment [CGA] is a multidimensional assessment of general health that can help to customise treatment and follow-up plans. The CGA has been proven effective in several health settings but has not been evaluated in randomised studies of patients with cancer. Our aim here was to assess the impact of the CGA on overall survival, function, and nutritional status of elderly patients with HNSCC. METHODS/DESIGN: EGeSOR is an open-label, multicentre, randomised, controlled, parallel-group trial in patients aged 70 years or older and receiving standard care for HNSCC. The intervention includes four components: the CGA conducted by a geriatrician before cancer treatment, participation of the same geriatrician in cancer treatment selection, a standardised geriatric therapeutic intervention designed by the same geriatrician; and geriatric follow-up for 24 months. The primary endpoint, assessed after 6 months, is a composite criterion including death, functional impairment [Activities of Daily Living score decrease ≥ 2], and weight loss ≥ 10%. Secondary endpoints include progression-free survival, unscheduled admissions, quality of life, treatment toxicities, costs, and completion of the planned cancer treatment. A centralised online system is used to perform 1:1 randomisation with a minimisation algorithm for centre, age, T and N stages, and tumour site [oral, oropharyngeal, hypopharyngeal, or laryngeal]. The estimated sample size is 704 patients, who are being recruited by 14 centres in 9 French cities. DISCUSSION: EGeSOR is the first randomised trial of the CGA in elderly cancer patients. We expect the CGA to have direct clinical benefits on the management of elderly patients with HNSCC. If this expectation is fulfilled, the trial may lead to modifications of the management model for elderly patients with cancer. TRIAL REGISTRATION: Trial registration: NCT02025062.


Assuntos
Protocolos Clínicos , Avaliação Geriátrica , Neoplasias de Cabeça e Pescoço/epidemiologia , Mortalidade , Estado Nutricional , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Humanos
6.
Lipids ; 45(11): 997-1009, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20811782

RESUMO

Fatty acid synthase (FAS) is responsible for the de novo synthesis of palmitate and stearate. This enzyme is activated by insulin and T(3), and inhibited by fatty acids. In this study, we show that insulin and T(3) have an inducing effect on FAS enzymatic activity, which is synergetic when both hormones are present. Octanoate and hexanoate specifically inhibit this hormonal effect. A similar inhibitory effect is observed at the level of protein expression. Transient transfections in HepG2 cells revealed that hexanoate inhibits, at least in part, FAS at a transcriptional level targeting the T(3) response element (TRE) on the FAS promoter. The effect of C6 on FAS expression cannot be attributed to a modification of insulin receptor activation or to a decrease in T(3) entry in the cells. Using bromo-hexanoate, we determined that hexanoate needs to undergo a transformation in order to have an effect. When incubating cells with triglyceride-hexanoate or carnitine-hexanoate, no effect on the enzymatic activity induced by insulin and T(3) is observed. A similar result was obtained when cells were incubated with betulinic acid, an inhibitor of the diacylglycerol acyltransferase. However, the incubation of cells with Triacsin C, a general inhibitor of acyl-CoA synthetases, completely reversed the inhibitory effect of hexanoate. Our results suggest that in hepatic cells, hexanoate needs to be activated into a CoA derivative in order to inhibit the insulin and T(3)-induced FAS expression. This effect is partially transcriptional, targeting the TRE on the FAS promoter.


Assuntos
Caproatos/farmacologia , Ácido Graxo Sintases/biossíntese , Insulina/farmacologia , Tri-Iodotironina/farmacologia , Animais , Caproatos/farmacocinética , Células Cultivadas , Embrião de Galinha , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Ativação Enzimática/efeitos dos fármacos , Indução Enzimática/efeitos dos fármacos , Ácido Graxo Sintases/antagonistas & inibidores , Ácido Graxo Sintases/genética , Ácido Graxo Sintases/metabolismo , Ácidos Graxos/farmacologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Antagonistas de Hormônios/farmacologia , Humanos , Antagonistas da Insulina/farmacologia , Regiões Promotoras Genéticas/efeitos dos fármacos , Tri-Iodotironina/antagonistas & inibidores
7.
Am J Physiol Endocrinol Metab ; 295(4): E884-94, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18682535

RESUMO

Fatty acid synthase (FAS) is a key enzyme of hepatic lipogenesis responsible for the synthesis of long-chain saturated fatty acids. This enzyme is mainly regulated at the transcriptional level by nutrients and hormones. In particular, glucose, insulin, and T(3) increase FAS activity, whereas glucagon and saturated and polyunsaturated fatty acids decrease it. In the present study we show that, in liver, T(3) and insulin were able to activate FAS enzymatic activity, mRNA expression, and gene transcription. We localized the T(3) response element (TRE) that mediates the T(3) genomic effect, on the FAS promoter between -741 and -696 bp that mediates the T(3) genomic effect. We show that both T(3) and insulin regulate FAS transcription via this sequence. The TRE binds a TR/RXR heterodimer even in the absence of hormone, and this binding is increased in response to T(3) and/or insulin treatment. The use of H7, a serine/threonine kinase inhibitor, reveals that a phosphorylation mechanism is implicated in the transcriptional regulation of FAS in response to both hormones. Specifically, we show that T(3) is able to modulate FAS transcription via a nongenomic action targeting the TRE through the activation of a PI 3-kinase-ERK1/2-MAPK-dependent pathway. Insulin also targets the TRE sequence, probably via the activation of two parallel pathways: Ras/ERK1/2 MAPK and PI 3-kinase/Akt. Finally, our data suggest that the nongenomic actions of T(3) and insulin are probably common to several TREs, as we observed similar effects on a classical DR4 consensus sequence.


Assuntos
Ácido Graxo Sintases/metabolismo , Insulina/farmacologia , Fígado/fisiologia , Tri-Iodotironina/farmacologia , Animais , Western Blotting , Células Cultivadas , Embrião de Galinha , Ensaio de Desvio de Mobilidade Eletroforética , MAP Quinases Reguladas por Sinal Extracelular/fisiologia , Ácido Graxo Sintases/genética , Fígado/efeitos dos fármacos , Fígado/enzimologia , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Plasmídeos/genética , Regiões Promotoras Genéticas/genética , Biossíntese de Proteínas/efeitos dos fármacos , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Elementos de Resposta , Transdução de Sinais/fisiologia , Transfecção , Tri-Iodotironina/genética
8.
J Cell Commun Signal ; 1(2): 113-25, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18481202

RESUMO

The stearoyl-CoA desaturase 1 (SCD1) catalyzes the synthesis of monounsaturated fatty acids. This enzyme is a critical control point regulating hepatic lipogenesis and lipid oxidation. Therefore SCD1 may be a potential therapeutic target in the treatment of obesity and metabolic syndrome. Regulation of SCD1 expression occurs primarily at the level of transcription. In the present study, we characterized the insulin response elements (IREs) and the insulin signaling pathway mediating the regulation of SCD1 gene transcription in liver. In chicken embryo hepatocytes (CEH) and HepG2 cells, insulin stimulates SCD1 promoter activity by 2.5 folds. This activation is mediated by two different IREs on the chicken promoter, one localized between -1,975 and -1,610 bp and one between -372 and -297 bp. The latter binds both NF-Y and SREBP-1 transcription factors in response to insulin. We also demonstrated that insulin induction of SCD1 gene expression and promoter activity is abolished by pre-incubation of cells with specific inhibitors of both PI3-kinase (LY294002) and mTor (Rapamycin) or by over-expression of a dominant negative mutant of PI3-kinase. The PI3-kinase and mTor pathway mediates the insulin response on both IREs. In summary, insulin activates SCD1 gene expression in liver via a signaling pathway that involves PI3-kinase and mTor and the downstream transcription factors NF-Y and SREBP-1. Sentence summary: Insulin regulates SCD1 gene expression via two different IREs. The most 3' IRE is localized between -372 and -297 bp and binds the NF-Y and SREBP-1 transcription factors in response to insulin. PI3-kinase and mTor mediate the action of insulin on both IREs.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA