Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Diabetologia ; 63(3): 597-610, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31915895

RESUMO

AIMS/HYPOTHESIS: The pathophysiology of type 1 diabetes has been linked to altered gut microbiota and more specifically to a shortage of intestinal production of the short-chain fatty acid (SCFA) butyrate, which may play key roles in maintaining intestinal epithelial integrity and in human and gut microbial metabolism. Butyrate supplementation can protect against autoimmune diabetes in mouse models. We thus set out to study the effect of oral butyrate vs placebo on glucose regulation and immune variables in human participants with longstanding type 1 diabetes. METHODS: We administered a daily oral dose of 4 g sodium butyrate or placebo for 1 month to 30 individuals with longstanding type 1 diabetes, without comorbidity or medication use, in a randomised (1:1), controlled, double-blind crossover trial, with a washout period of 1 month in between. Participants were randomly allocated to the 'oral sodium butyrate capsules first' or 'oral placebo capsules first' study arm in blocks of five. The clinical investigator received blinded medication from the clinical trial pharmacy. All participants, people doing measurements or examinations, or people assessing the outcomes were blinded to group assignment. The primary outcome was a change in the innate immune phenotype (monocyte subsets and in vitro cytokine production). Secondary outcomes were changes in blood markers of islet autoimmunity (cell counts, lymphocyte stimulation indices and CD8 quantum dot assays), glucose and lipid metabolism, beta cell function (by mixed-meal test), gut microbiota and faecal SCFA. The data was collected at the Amsterdam University Medical Centers. RESULTS: All 30 participants were analysed. Faecal butyrate and propionate levels were significantly affected by oral butyrate supplementation and butyrate treatment was safe. However, this modulation of intestinal SCFAs did not result in any significant changes in adaptive or innate immunity, or in any of the other outcome variables. In our discussion, we elaborate on this important discrepancy with previous animal work. CONCLUSIONS/INTERPRETATION: Oral butyrate supplementation does not significantly affect innate or adaptive immunity in humans with longstanding type 1 diabetes. TRIAL REGISTRATION: Netherlands Trial Register: NL4832 (www.trialregister.nl). DATA AVAILABILITY: Raw sequencing data are available in the European Nucleotide Archive repository (https://www.ebi.ac.uk/ena/browse) under study PRJEB30292. FUNDING: The study was funded by a Le Ducq consortium grant, a CVON grant, a personal ZONMW-VIDI grant and a Dutch Heart Foundation grant.


Assuntos
Autoimunidade/efeitos dos fármacos , Ácido Butírico/administração & dosagem , Diabetes Mellitus Tipo 1/tratamento farmacológico , Imunidade Inata/efeitos dos fármacos , Ilhotas Pancreáticas/imunologia , Imunidade Adaptativa/efeitos dos fármacos , Administração Oral , Adulto , Ácido Butírico/efeitos adversos , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/patologia , Progressão da Doença , Feminino , Humanos , Ilhotas Pancreáticas/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Países Baixos , Fatores de Tempo , Adulto Jovem
2.
Stem Cells ; 36(11): 1778-1788, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30063804

RESUMO

In experimental models, mesenchymal stem cells (MSCs) can modulate various immune responses implicated in the pathogenesis of sepsis. Intravenous injection of lipopolysaccharide (LPS) into healthy subjects represents a model with relevance for the host response to sepsis. To explore the use of MSCs in sepsis, we determined their effect on the response to intravenous LPS in a randomized study in 32 healthy subjects with four treatment arms: placebo or allogeneic adipose MSCs (ASCs) intravenously at either 0.25 × 106 , 1 × 106 , or 4 × 106 cells/kg; all subjects received LPS intravenously (2 ng/kg) one hour after the end of ASC infusion (Trial Register number 2014-002537-63, clinicaltrials.gov identifier NCT02328612). Infusion of ASCs was well tolerated. The high ASC dose increased the febrile response, exerted mixed pro-inflammatory (enhanced interleukin-8 and nucleosome release) and anti-inflammatory effects (increased interleukin-10 and transforming growth factor-ß release), and enhanced coagulation activation and reduced the fibrinolytic response. Blood leukocyte transcriptome analyses showed a biphasic effect of ASCs on the LPS response: at 2 hours post LPS, ASC-infused subjects displayed higher expression of genes involved in innate immune pathways, whereas at 4 hours post LPS these subjects had lower expression of innate immune pathway genes. Infusion of ASCs did not modify the "ex vivo" responsiveness of whole blood to various bacterial agonists. These results indicate that intravenous infusion of allogeneic ASCs (4 × 106 cells/kg) has a variety of proinflammatory, anti-inflammatory, and procoagulant effects during human endotoxemia. Further studies are needed to assess the safety and efficacy of ASCs in sepsis patients. Stem Cells 2018;36:1778-1788.


Assuntos
Tecido Adiposo/metabolismo , Infusões Intravenosas/métodos , Lipopolissacarídeos/metabolismo , Células-Tronco Mesenquimais/metabolismo , Tecido Adiposo/citologia , Feminino , Humanos , Masculino
3.
J Inherit Metab Dis ; 42(2): 303-312, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30793331

RESUMO

INTRODUCTION: Currently, no therapies are available for Zellweger spectrum disorders (ZSDs), a group of genetic metabolic disorders characterised by a deficiency of functional peroxisomes. In a previous study, we showed that oral cholic acid (CA) treatment can suppress bile acid synthesis in ZSD patients and, thereby, decrease plasma levels of toxic C27 -bile acid intermediates, one of the biochemical abnormalities in these patients. However, no effect on clinically relevant outcome measures could be observed after 9 months of CA treatment. It was noted that, in patients with advanced liver disease, caution is needed because of possible hepatotoxicity. METHODS: An extension study of the previously conducted pretest-posttest design study was conducted including 17 patients with a ZSD. All patients received oral CA for an additional period of 12 months, encompassing a total of 21 months of treatment. Multiple clinically relevant parameters and markers for bile acid synthesis were assessed after 15 and 21 months of treatment. RESULTS: Bile acid synthesis was still suppressed after 21 months of CA treatment, accompanied with reduced levels of C27 -bile acid intermediates in plasma. These levels significantly increased again after discontinuation of CA. No significant changes were found in liver tests, liver elasticity, coagulation parameters, fat-soluble vitamin levels or body weight. CONCLUSIONS: Although CA treatment did lead to reduced levels of toxic C27 -bile acid intermediates in ZSD patients without severe liver fibrosis or cirrhosis, no improvement of clinically relevant parameters was observed after 21 months of treatment. We discuss the implications for CA therapy in ZSD based on these results.


Assuntos
Ácido Cólico/uso terapêutico , Síndrome de Zellweger/tratamento farmacológico , Administração Oral , Adolescente , Adulto , Ácidos e Sais Biliares/metabolismo , Biomarcadores/sangue , Criança , Pré-Escolar , Ácido Cólico/sangue , Feminino , Humanos , Fígado/metabolismo , Hepatopatias/tratamento farmacológico , Hepatopatias/metabolismo , Masculino , Peroxissomos/metabolismo , Adulto Jovem , Síndrome de Zellweger/sangue , Síndrome de Zellweger/metabolismo
4.
BMC Pulm Med ; 17(1): 121, 2017 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-28877711

RESUMO

BACKGROUND: Inhalation of particulate matter, as part of air pollution, is associated with increased morbidity and mortality. Nanoparticles (< 100 nm) are likely candidates for triggering inflammatory responses and activation of coagulation pathways because of their ability to enter lung cells and pass bronchial mucosa. We tested the hypothesis that bronchial segmental instillation of carbon nanoparticles causes inflammation and activation of coagulation pathways in healthy humans in vivo. METHODS: This was an investigator-initiated, randomized controlled, dose-escalation study in 26 healthy males. Participants received saline (control) in one lung segment and saline (placebo) or carbon nanoparticles 10 µg, 50 µg, or 100 µg in the contra-lateral lung. Six hours later, blood and bronchoalveolar lavage fluid (BALF) was collected for inflammation and coagulation parameters. RESULTS: There was a significant dose-dependent increase in blood neutrophils (p = 0.046) after challenge with carbon nanoparticles. The individual top-dose of 100 µg showed a significant (p = 0.05) increase in terms of percentage neutrophils in blood as compared to placebo. CONCLUSIONS: This study shows a dose-dependent effect of bronchial segmental challenge with carbon nanoparticles on circulating neutrophils of healthy volunteers. This suggests that nanoparticles in the respiratory tract induce systemic inflammation. TRIAL REGISTRATION: Dutch Trial Register no. 2976. 11 July 2011. http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=2976.


Assuntos
Poluição do Ar/efeitos adversos , Exposição por Inalação/efeitos adversos , Nanopartículas/administração & dosagem , Nanotubos de Carbono/efeitos adversos , Neutrófilos/citologia , Administração por Inalação , Adulto , Testes de Provocação Brônquica , Líquido da Lavagem Broncoalveolar/química , Voluntários Saudáveis , Humanos , Inflamação/induzido quimicamente , Pulmão/metabolismo , Masculino , Tamanho da Partícula , Material Particulado , Adulto Jovem
5.
J Inherit Metab Dis ; 39(6): 859-868, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27469511

RESUMO

INTRODUCTION: Zellweger spectrum disorders (ZSDs) are characterized by a failure in peroxisome formation, caused by autosomal recessive mutations in different PEX genes. At least some of the progressive and irreversible clinical abnormalities in patients with a ZSD, particularly liver dysfunction, are likely caused by the accumulation of toxic bile acid intermediates. We investigated whether cholic acid supplementation can suppress bile acid synthesis, reduce accumulation of toxic bile acid intermediates and improve liver function in these patients. METHODS: An open label, pretest-posttest design study was conducted including 19 patients with a ZSD. Participants were followed longitudinally during a period of 2.5 years prior to the start of the intervention. Subsequently, all patients received oral cholic acid and were followed during 9 months of treatment. Bile acids, peroxisomal metabolites, liver function and liver stiffness were measured at baseline and 4, 12 and 36 weeks after start of cholic acid treatment. RESULTS: During cholic acid treatment, bile acid synthesis decreased in the majority of patients. Reduced levels of bile acid intermediates were found in plasma and excretion of bile acid intermediates in urine was diminished. In patients with advanced liver disease (n = 4), cholic acid treatment resulted in increased levels of plasma transaminases, bilirubin and cholic acid with only a minor reduction in bile acid intermediates. CONCLUSIONS: Oral cholic acid therapy can be used in the majority of patients with a ZSD, leading to at least partial suppression of bile acid synthesis. However, caution is needed in patients with advanced liver disease due to possible hepatotoxic effects.


Assuntos
Ácido Cólico/uso terapêutico , Síndrome de Zellweger/tratamento farmacológico , Adolescente , Adulto , Ácidos e Sais Biliares/metabolismo , Bilirrubina/sangue , Criança , Pré-Escolar , Ácido Cólico/sangue , Feminino , Humanos , Fígado/metabolismo , Hepatopatias/tratamento farmacológico , Hepatopatias/metabolismo , Estudos Longitudinais , Masculino , Endopeptidase Neutra Reguladora de Fosfato PHEX/metabolismo , Transaminases/sangue , Adulto Jovem , Síndrome de Zellweger/sangue , Síndrome de Zellweger/metabolismo
6.
Ther Drug Monit ; 34(3): 320-5, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22561586

RESUMO

BACKGROUND: Posaconazole is indicated for prophylaxis and salvage therapy of invasive fungal infections. Based on pharmacokinetic-pharmacodynamic data, minimum serum concentrations for each indication have been proposed, for example, for prophylaxis >0.5-0.7 mg/L and for primary therapy >1.0 mg/L. Several drugs and comorbidities have been identified to hinder reaching target concentrations. It is postulated that patients with interacting drugs or comorbidities should be monitored for posaconazole concentrations. PATIENTS AND METHODS: Patients aged 18 years and above were included for retrospective analysis if at least 1 serum posaconazole concentration was measured in our hospital between June 2009 and May 2010. Serum posaconazole concentrations were measured using a validated liquid chromatographic method with tandem mass-spectrometric analytical method. Patient characteristics, underlying disease, comedication, comorbidities, and therapeutic drug monitoring (TDM) interventions were collected retrospectively, based on (electronic) medical records. RESULTS: Seventeen patients were included, from whom 42 samples for posaconazole measurement were collected. In total, 8 patients did not reach adequate posaconazole concentration. Sixty percent of patients using a proton pump inhibitor (PPI) did not reach target concentration with a corresponding median concentration of 0.48 mg/L. PPI usage was shown to significantly increase the risk of attaining below-target serum posaconazole concentration (P = 0.04 for all measurements). Graft-versus-host disease and diarrhea were associated with significant below-target concentrations (P = 0.03 and P < 0.001, respectively, for all measurements). One patient developed a breakthrough pulmonary aspergillosis at low posaconazole concentration (0.37 mg/L). Two patients had high concentrations (>3 mg/L), without adverse events. After TDM intervention, 3 out of 4 patients (75%) reached target concentration by spreading the administration of the dose. CONCLUSIONS: Below-target posaconazole concentrations were significantly more frequent in PPI users, graft-versus-host disease, and diarrhea. TDM seemed to be a helpful tool to identify low concentrations and to optimize posaconazole treatment.


Assuntos
Antifúngicos/sangue , Monitoramento de Medicamentos/métodos , Triazóis/sangue , Triazóis/uso terapêutico , Adulto , Antifúngicos/uso terapêutico , Feminino , Seguimentos , Doenças Hematológicas/sangue , Doenças Hematológicas/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Micoses/sangue , Micoses/tratamento farmacológico , Projetos Piloto , Estudos Retrospectivos , Resultado do Tratamento
7.
Cancers (Basel) ; 13(10)2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-34068407

RESUMO

DNA hypermethylation is common in colon cancer. Previously, we have shown that methylation of WNT target genes predicts poor prognosis in stage II colon cancer. The primary objective of this study was to assess whether pre-operative treatment with decitabine can decrease methylation and increase the expression of WNT target genes APCDD1, AXIN2 and DKK1 in colon cancer patients. A clinical study was conducted, investigating these potential effects of decitabine in colon cancer patients (DECO). Patients were treated two times with 25 mg/m2 decitabine before surgery. Methylation and expression of LINE1 and WNT target genes (primary outcome) and expression of endogenous retroviral genes (secondary outcome) were analysed in pre- and post-treatment tumour samples using pyrosequencing and rt-PCR. Ten patients were treated with decitabine and eighteen patients were used as controls. Decitabine treatment only marginally decreased LINE1 methylation. More importantly, no differences in methylation or expression of WNT target or endogenous retroviral genes were observed. Due to the lack of an effect on primary and secondary outcomes, the study was prematurely closed. In conclusion, pre-operative treatment with decitabine is safe, but with the current dosing, the primary objective, increased WNT target gene expression, cannot be achieved.

8.
Pediatr Infect Dis J ; 33(7): 731-3, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24445830

RESUMO

Vancomycin trough serum concentrations were below therapeutic range (8-15 mg/L) in 58% of 124 pediatric oncology patients receiving 60 mg/kg/d divided qid. Patients <6 and between 6 and 12 years had significantly lower trough concentrations than patients >12 years. A vancomycin dosage of 60 mg/kg/d is inadequate for pediatric oncology patients >12 years.


Assuntos
Antibacterianos/administração & dosagem , Antibacterianos/farmacocinética , Vancomicina/administração & dosagem , Vancomicina/farmacocinética , Adolescente , Antibacterianos/farmacologia , Infecções Bacterianas/tratamento farmacológico , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Neoplasias/complicações , Estudos Retrospectivos , Soro/química , Vancomicina/farmacologia
9.
Am J Clin Nutr ; 99(6): 1440-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24695897

RESUMO

BACKGROUND: Nitric oxide (NO) is essential for the optimal perfusion of the heart and its vasculature. NO may be insufficient in surgical patients because its precursor arginine is decreased, and the inhibitor of NO synthesis asymmetric dimethylarginine (ADMA) is increased. Besides arginine, the presence of other amino acids essential for the proper metabolism of cardiac cells may be decreased too. Supplementation of these amino acids with enteral and parenteral nutrition before, during, and after surgery may augment the myocardial and plasma arginine:ADMA ratio and availability of amino acids. Myocardial glucose metabolism and nutritional conditioning may result in a reduction of cardiac injury and support rapid recovery after major surgery. OBJECTIVE: We investigated the effect of nutrition before, during, and after surgery on amino acids and the myocardial arginine:ADMA ratio and its relation to myocardial glucose metabolism. DESIGN: In this trial, 33 patients who were undergoing off-pump coronary artery bypass grafting (CABG) were randomly assigned between enteral, parenteral, or no nutrition (control) from 2 d before, during, and until 2 d after surgery. Both enteral and parenteral solutions were prepared with commercially available products and included proteins or amino acids, glucose, vitamins, and minerals. Concentrations of amino acids including ADMA were analyzed in myocardial tissue and plasma samples. ¹8F-fluorodeoxyglucose positron emission tomography was performed before and after surgery to assess myocardial glucose metabolism. RESULTS: The myocardial arginine:ADMA ratio increased during surgery and was significantly higher in the enteral and parenteral groups than in the control group [median (IQR): 115.0 (98.0-142.2) (P = 0.012), 116.9 (100.3-135.3) (P = 0.004), and 93.3 (82.7-101.1), respectively]. Furthermore, the change in the preoperative to postoperative plasma arginine:ADMA ratio correlated with the change in myocardial glucose metabolism in positron emission tomography (r = 0.427, P = 0.033). CONCLUSION: Enteral or parenteral nutrition before, during, and after CABG may positively influence myocardial glucose metabolism by increasing the plasma and myocardial arginine:ADMA ratio.


Assuntos
Arginina/análogos & derivados , Arginina/metabolismo , Ponte de Artéria Coronária sem Circulação Extracorpórea/efeitos adversos , Nutrição Enteral , Glucose/metabolismo , Miocárdio/metabolismo , Nutrição Parenteral , Idoso , Algoritmos , Arginina/sangue , Nutrição Enteral/efeitos adversos , Fluordesoxiglucose F18 , Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Estado Nutricional , Nutrição Parenteral/efeitos adversos , Assistência Perioperatória , Tomografia por Emissão de Pósitrons , Cuidados Pós-Operatórios , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Cuidados Pré-Operatórios , Risco
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA