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1.
N Engl J Med ; 388(4): 299-309, 2023 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-36720132

RESUMO

BACKGROUND: Extracorporeal cardiopulmonary resuscitation (CPR) restores perfusion and oxygenation in a patient who does not have spontaneous circulation. The evidence with regard to the effect of extracorporeal CPR on survival with a favorable neurologic outcome in refractory out-of-hospital cardiac arrest is inconclusive. METHODS: In this multicenter, randomized, controlled trial conducted in the Netherlands, we assigned patients with an out-of-hospital cardiac arrest to receive extracorporeal CPR or conventional CPR (standard advanced cardiac life support). Eligible patients were between 18 and 70 years of age, had received bystander CPR, had an initial ventricular arrhythmia, and did not have a return of spontaneous circulation within 15 minutes after CPR had been initiated. The primary outcome was survival with a favorable neurologic outcome, defined as a Cerebral Performance Category score of 1 or 2 (range, 1 to 5, with higher scores indicating more severe disability) at 30 days. Analyses were performed on an intention-to-treat basis. RESULTS: Of the 160 patients who underwent randomization, 70 were assigned to receive extracorporeal CPR and 64 to receive conventional CPR; 26 patients who did not meet the inclusion criteria at hospital admission were excluded. At 30 days, 14 patients (20%) in the extracorporeal-CPR group were alive with a favorable neurologic outcome, as compared with 10 patients (16%) in the conventional-CPR group (odds ratio, 1.4; 95% confidence interval, 0.5 to 3.5; P = 0.52). The number of serious adverse events per patient was similar in the two groups. CONCLUSIONS: In patients with refractory out-of-hospital cardiac arrest, extracorporeal CPR and conventional CPR had similar effects on survival with a favorable neurologic outcome. (Funded by the Netherlands Organization for Health Research and Development and Maquet Cardiopulmonary [Getinge]; INCEPTION ClinicalTrials.gov number, NCT03101787.).


Assuntos
Reanimação Cardiopulmonar , Parada Cardíaca Extra-Hospitalar , Humanos , Suporte Vital Cardíaco Avançado/métodos , Reanimação Cardiopulmonar/métodos , Hospitalização , Parada Cardíaca Extra-Hospitalar/mortalidade , Parada Cardíaca Extra-Hospitalar/terapia , Fibrilação Ventricular/terapia , Países Baixos
2.
N Engl J Med ; 380(15): 1397-1407, 2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30883057

RESUMO

BACKGROUND: Ischemic heart disease is a major cause of out-of-hospital cardiac arrest. The role of immediate coronary angiography and percutaneous coronary intervention (PCI) in the treatment of patients who have been successfully resuscitated after cardiac arrest in the absence of ST-segment elevation myocardial infarction (STEMI) remains uncertain. METHODS: In this multicenter trial, we randomly assigned 552 patients who had cardiac arrest without signs of STEMI to undergo immediate coronary angiography or coronary angiography that was delayed until after neurologic recovery. All patients underwent PCI if indicated. The primary end point was survival at 90 days. Secondary end points included survival at 90 days with good cerebral performance or mild or moderate disability, myocardial injury, duration of catecholamine support, markers of shock, recurrence of ventricular tachycardia, duration of mechanical ventilation, major bleeding, occurrence of acute kidney injury, need for renal-replacement therapy, time to target temperature, and neurologic status at discharge from the intensive care unit. RESULTS: At 90 days, 176 of 273 patients (64.5%) in the immediate angiography group and 178 of 265 patients (67.2%) in the delayed angiography group were alive (odds ratio, 0.89; 95% confidence interval [CI], 0.62 to 1.27; P = 0.51). The median time to target temperature was 5.4 hours in the immediate angiography group and 4.7 hours in the delayed angiography group (ratio of geometric means, 1.19; 95% CI, 1.04 to 1.36). No significant differences between the groups were found in the remaining secondary end points. CONCLUSIONS: Among patients who had been successfully resuscitated after out-of-hospital cardiac arrest and had no signs of STEMI, a strategy of immediate angiography was not found to be better than a strategy of delayed angiography with respect to overall survival at 90 days. (Funded by the Netherlands Heart Institute and others; COACT Netherlands Trial Register number, NTR4973.).


Assuntos
Angiografia Coronária , Eletrocardiografia , Cardiopatias/diagnóstico por imagem , Parada Cardíaca Extra-Hospitalar/diagnóstico por imagem , Intervenção Coronária Percutânea , Tempo para o Tratamento , Idoso , Feminino , Cardiopatias/complicações , Cardiopatias/terapia , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Parada Cardíaca Extra-Hospitalar/mortalidade , Parada Cardíaca Extra-Hospitalar/terapia
3.
Crit Care Med ; 50(2): e129-e142, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34637414

RESUMO

OBJECTIVES: The optimal targeted temperature in patients with shockable rhythm is unclear, and current guidelines recommend targeted temperature management with a correspondingly wide range between 32°C and 36°C. Our aim was to study survival and neurologic outcome associated with targeted temperature management strategy in postarrest patients with initial shockable rhythm. DESIGN: Observational substudy of the Coronary Angiography after Cardiac Arrest without ST-segment Elevation trial. SETTING: Nineteen hospitals in The Netherlands. PATIENTS: The Coronary Angiography after Cardiac Arrest trial randomized successfully resuscitated patients with shockable rhythm and absence of ST-segment elevation to a strategy of immediate or delayed coronary angiography. In this substudy, 459 patients treated with mild therapeutic hypothermia (32.0-34.0°C) or targeted normothermia (36.0-37.0°C) were included. Allocation to targeted temperature management strategy was at the discretion of the physician. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: After 90 days, 171 patients (63.6%) in the mild therapeutic hypothermia group and 129 (67.9%) in the targeted normothermia group were alive (hazard ratio, 0.86 [95% CI, 0.62-1.18]; log-rank p = 0.35; adjusted odds ratio, 0.89; 95% CI, 0.45-1.72). Patients in the mild therapeutic hypothermia group had longer ICU stay (4 d [3-7 d] vs 3 d [2-5 d]; ratio of geometric means, 1.32; 95% CI, 1.15-1.51), lower blood pressures, higher lactate levels, and increased need for inotropic support. Cerebral Performance Category scores at ICU discharge and 90-day follow-up and patient-reported Mental and Physical Health Scores at 1 year were similar in the two groups. CONCLUSIONS: In the context of out-of-hospital cardiac arrest with shockable rhythm and no ST-elevation, treatment with mild therapeutic hypothermia was not associated with improved 90-day survival compared with targeted normothermia. Neurologic outcomes at 90 days as well as patient-reported Mental and Physical Health Scores at 1 year did not differ between the groups.


Assuntos
Angiografia Coronária/métodos , Cardioversão Elétrica/estatística & dados numéricos , Hipotermia Induzida/normas , Parada Cardíaca Extra-Hospitalar/terapia , Idoso , Angiografia Coronária/estatística & dados numéricos , Feminino , Humanos , Hipotermia Induzida/métodos , Hipotermia Induzida/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Países Baixos , Parada Cardíaca Extra-Hospitalar/epidemiologia , Ressuscitação/métodos , Ressuscitação/estatística & dados numéricos , Resultado do Tratamento
4.
J Immunol ; 200(10): 3626-3634, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29654208

RESUMO

The cytokine IFN-γ has well-established antibacterial properties against the bacterium Salmonella enterica in phagocytes, but less is known about the effects of IFN-γ on Salmonella-infected nonphagocytic cells, such as intestinal epithelial cells (IECs) and fibroblasts. In this article, we show that exposing human and murine IECs and fibroblasts to IFN-γ following infection with Salmonella triggers a novel form of cell death that is neither pyroptosis nor any of the major known forms of programmed cell death. Cell death required IFN-γ-signaling via STAT1-IRF1-mediated induction of guanylate binding proteins and the presence of live Salmonella in the cytosol. In vivo, ablating IFN-γ signaling selectively in murine IECs led to higher bacterial burden in colon contents and increased inflammation in the intestine of infected mice. Together, these results demonstrate that IFN-γ signaling triggers release of Salmonella from the Salmonella-containing vacuole into the cytosol of infected nonphagocytic cells, resulting in a form of nonpyroptotic cell death that prevents bacterial spread in the gut.


Assuntos
Morte Celular/imunologia , Interferon gama/imunologia , Fagócitos/imunologia , Piroptose/imunologia , Infecções por Salmonella/imunologia , Salmonella enterica/imunologia , Células 3T3 , Animais , Linhagem Celular , Citosol/imunologia , Citosol/microbiologia , Células Epiteliais/imunologia , Células Epiteliais/microbiologia , Fibroblastos/imunologia , Fibroblastos/microbiologia , Humanos , Inflamação/imunologia , Inflamação/microbiologia , Fator Regulador 1 de Interferon/imunologia , Intestinos/imunologia , Intestinos/microbiologia , Camundongos , Fagócitos/microbiologia , Fator de Transcrição STAT1/imunologia , Infecções por Salmonella/microbiologia
5.
Perfusion ; 35(7): 664-671, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-31948360

RESUMO

BACKGROUND: Pulmonary edema and left ventricular thrombosis may arise during veno-arterial extracorporeal life support due to an increase in cardiac load. This mechanical stress can be reduced through different left ventricular unloading techniques. We set out to quantitatively summarize the hemodynamic effects of available methods in patients treated with veno-arterial extracorporeal life support. METHODS: Literature was systematically searched for studies reporting left ventricular unloading during veno-arterial extracorporeal life support as reflected by changes in left atrial pressure, pulmonary capillary wedge pressure, diastolic pulmonary artery pressure, or left ventricular end-diastolic pressure. For studies including ⩾10 patients per group, changes in these parameters were pooled using (1) standardized mean differences and (2) ratio of means. Assessment of potential bias was performed for all studies. RESULTS: Eight studies met the inclusion criteria. Reported techniques included use of intra-aortic balloon pump (n = 1), micro-axial blood pump (Impella®, n = 2), left ventricular venting (n = 1), and atrial septostomy (n = 4). Overall, left ventricular unloading was associated with a statistically significant reduction in preload parameters (standardized mean differences = -1.05 (95% confidence interval = -1.24 to -0.86) and ratio of means = 0.60 (0.47 to 0.76)). Effect sizes were strongest for micro-axial blood pump and atrial septostomy (standardized mean differences = -1.11 (-1.55 to -0.68) and -1.22 (-1.47 to -0.96), and ratio of means = 0.58 (0.39 to 0.86) and 0.54 (0.36 to 0.83), respectively). CONCLUSION: Left ventricular unloading was associated with a significant reduction in left ventricular preload parameters in the setting of veno-arterial extracorporeal life support. This effect may be most pronounced for micro-axial blood pump and atrial septostomy.


Assuntos
Ventrículos do Coração/fisiopatologia , Hemodinâmica/fisiologia , Adulto , Idoso , Oxigenação por Membrana Extracorpórea/métodos , Humanos , Pessoa de Meia-Idade
6.
Eur J Immunol ; 48(2): 344-354, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28952147

RESUMO

The efficacy of cancer therapeutic antibodies varies considerably among patients. Anti-cancer antibodies act through different mechanisms, including antibody-dependent cellular cytotoxicity (ADCC) triggered via Fcγ receptors (FcγR). This phagocyte ADCC can be promoted by interference with CD47-SIRPα interactions, but the magnitude of this enhancement also varies among individuals. Both FcγR and SIRPα display considerable genetic variation, and we investigated whether this explains some of the variability in ADCC. Because of linkage disequilibrium between FcγR variants the interpretation of previous reports suggesting a potential link between FcγR polymorphisms and ADCC has been troublesome. We performed an integrated genetic analysis that enables stratification. ADCC by activated human neutrophils towards Trastuzumab-coated breast cancer cells was predominantly dependent on FcγRIIa. Neutrophils from individuals with the FcγRIIa-131H polymorphic variant displayed significantly higher killing capacity relative to those with FcγRIIa-131R. Furthermore, ADCC was consistently enhanced by targeting CD47-SIRPα interactions, and there were no significant functional differences between the two most prevalent SIRPα polymorphic variants. Thus, neutrophil ADCC capacity is directly related to the FcγRIIa polymorphism, and targeting CD47-SIRPα interactions enhances ADCC independently of FcγR and SIRPα genotype, thereby further suggesting that CD47-SIRPα interference might be a generic strategy for potentiating the efficacy of antibody therapy in cancer.


Assuntos
Citotoxicidade Celular Dependente de Anticorpos/genética , Antígenos de Diferenciação/genética , Neoplasias da Mama/genética , Genótipo , Imunoterapia/métodos , Neutrófilos/fisiologia , Receptores de IgG/genética , Receptores Imunológicos/genética , Antígenos de Diferenciação/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias da Mama/imunologia , Antígeno CD47/metabolismo , Linhagem Celular Tumoral , Feminino , Predisposição Genética para Doença , Humanos , Desequilíbrio de Ligação , Polimorfismo Genético , Receptor ErbB-2/imunologia , Receptores de IgG/metabolismo , Receptores Imunológicos/metabolismo , Trastuzumab/farmacologia , Trastuzumab/uso terapêutico , Resultado do Tratamento
7.
Am Heart J ; 210: 58-68, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30738245

RESUMO

Return of spontaneous circulation occurs in less than 10% of patients with cardiac arrest undergoing cardiopulmonary resuscitation (CPR) for more than 15 minutes. Studies suggest that extracorporeal life support during cardiopulmonary resuscitation (ECPR) improves survival rate in these patients. These studies, however, are hampered by their non-randomized, observational design and are mostly single-center. A multicenter, randomized controlled trial is urgently warranted to evaluate the effectiveness of ECPR. HYPOTHESIS: We hypothesize that early initiation of ECPR in refractory out-of-hospital cardiac arrest (OHCA) improves the survival rate with favorable neurological status. STUDY DESIGN: The INCEPTION trial is an investigator-initiated, prospective, multicenter trial that will randomly allocate 110 patients to either continued CPR or ECPR in a 1:1 ratio. Patients eligible for inclusion are adults (≤ 70 years) with witnessed OHCA presenting with an initial rhythm of ventricular fibrillation (VF) or ventricular tachycardia (VT), who received bystander basic life support and who fail to achieve sustained return of spontaneous circulation within 15 minutes of cardiopulmonary resuscitation by emergency medical services. The primary endpoint of the study is 30-day survival rate with favorable neurological status, defined as 1 or 2 on the Cerebral Performance Category score. The secondary endpoints include 3, 6 and 12-month survival rate with favorable neurological status and the cost-effectiveness of ECPR compared to CCPR. SUMMARY: The INCEPTION trial aims to determine the clinical benefit for the use of ECPR in patients with refractory OHCA presenting with VF/VT. Additionally, the feasibility and cost-effectiveness of ECPR will be evaluated.


Assuntos
Reanimação Cardiopulmonar/métodos , Oxigenação por Membrana Extracorpórea , Estudos Multicêntricos como Assunto , Parada Cardíaca Extra-Hospitalar/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto , Tempo para o Tratamento , Adulto , Idoso , Circulação Sanguínea , Desfibriladores , Serviços Médicos de Emergência , Humanos , Análise de Intenção de Tratamento , Pessoa de Meia-Idade , Exame Neurológico , Parada Cardíaca Extra-Hospitalar/mortalidade , Estudos Prospectivos , Taxa de Sobrevida , Taquicardia/terapia , Fatores de Tempo , Fibrilação Ventricular/terapia
8.
Proc Natl Acad Sci U S A ; 112(2): 560-5, 2015 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-25548165

RESUMO

Many significant bacterial pathogens have evolved virulence mechanisms to evade degradation and exposure to reactive oxygen (ROS) and reactive nitrogen species (RNS), allowing them to survive and replicate inside their hosts. Due to the highly reactive and short-lived nature of ROS and RNS, combined with limitations of conventional detection agents, the mechanisms underlying these evasion strategies remain poorly understood. In this study, we describe a system that uses redox-sensitive GFP to nondisruptively measure real-time fluctuations in the intrabacterial redox environment. Using this system coupled with high-throughput microscopy, we report the intrabacterial redox dynamics of Salmonella enterica Typhimurium (S. Typhimurium) residing inside macrophages. We found that the bacterial SPI-2 type III secretion system is required for ROS evasion strategies and this evasion relies on an intact Salmonella-containing vacuole (SCV) within which the bacteria reside during infection. Additionally, we found that cytosolic bacteria that escape the SCV experience increased redox stress in human and murine macrophages. These results highlight the existence of specialized evasion strategies used by intracellular pathogens that either reside inside a vacuole or "escape" into the cytosol. Taken together, the use of redox-sensitive GFP inside Salmonella significantly advances our understanding of ROS and RNS evasion strategies during infection. This technology can also be applied to measuring bacterial oxidative and nitrosative stress dynamics under different conditions in a wide variety of bacteria.


Assuntos
Macrófagos/metabolismo , Macrófagos/microbiologia , Salmonella typhimurium/metabolismo , Animais , Linhagem Celular , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HeLa , Humanos , Camundongos , Estresse Oxidativo , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Explosão Respiratória , Salmonella typhimurium/genética , Salmonella typhimurium/patogenicidade , Vacúolos/metabolismo , Vacúolos/microbiologia
9.
Perfusion ; 33(1_suppl): 31-41, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29788834

RESUMO

Extracorporeal life support (ECLS) is a mainstay of current practice in severe respiratory, circulatory or cardiac failure refractory to conventional management. The inherent complexity of different ECLS modes and their influence on the native pulmonary and cardiovascular system require patient-specific tailoring to optimize outcome. Echocardiography plays a key role throughout the ECLS care, including patient selection, adequate placement of cannulas, monitoring, weaning and follow-up after decannulation. For this purpose, echocardiographers require specific ECLS-related knowledge and skills, which are outlined here.


Assuntos
Ecocardiografia/métodos , Oxigenação por Membrana Extracorpórea/métodos , Cuidados para Prolongar a Vida/métodos , Feminino , Humanos , Masculino
11.
J Infect Dis ; 215(8): 1245-1254, 2017 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-28368463

RESUMO

Intestinal helminth infections occur predominantly in regions where exposure to enteric bacterial pathogens is also common. Helminth infections inhibit host immunity against microbial pathogens, which has largely been attributed to the induction of regulatory or type 2 (Th2) immune responses. Here we demonstrate an additional 3-way interaction in which helminth infection alters the metabolic environment of the host intestine to enhance bacterial pathogenicity. We show that an ongoing helminth infection increased colonization by Salmonella independently of T regulatory or Th2 cells. Instead, helminth infection altered the metabolic profile of the intestine, which directly enhanced bacterial expression of Salmonella pathogenicity island 1 (SPI-1) genes and increased intracellular invasion. These data reveal a novel mechanism by which a helminth-modified metabolome promotes susceptibility to bacterial coinfection.


Assuntos
Coinfecção/imunologia , Helmintíase/imunologia , Enteropatias Parasitárias/imunologia , Mucosa Intestinal/metabolismo , Metaboloma , Infecções por Salmonella/imunologia , Células Th2/imunologia , Animais , Coinfecção/microbiologia , Coinfecção/parasitologia , Células HeLa , Humanos , Intestinos/microbiologia , Intestinos/parasitologia , Camundongos , Camundongos Endogâmicos C57BL , Salmonella typhimurium/genética
12.
J Proteome Res ; 15(5): 1613-22, 2016 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-27018634

RESUMO

Enteropathogenic and enterohemorrhagic Escherichia coli cause enteric diseases resulting in significant morbidity and mortality worldwide. These pathogens remain extracellular and translocate a set of type III secreted effector proteins into host cells to promote bacterial virulence. Effectors manipulate host cell pathways to facilitate infection by interacting with a variety of host targets, yet the binding partners and mechanism of action of many effectors remain elusive. We performed a mass spectrometry screen to identify host targets for a library of effectors. We found five known effector targets and discovered four novel interactions. Interestingly, we identified multiple effectors that interacted with the microtubule associated protein, ensconsin. Using co-immunoprecipitations, we confirmed that NleB1 and EspL interacted with ensconsin in a region that corresponded to its microtubule binding domain. Ensconsin is an essential cofactor of kinesin-1 that is required for intracellular trafficking, and we demonstrated that intracellular trafficking was severely disrupted during wild type EPEC infections but not during infections with ΔnleB1 or ΔespL mutants. Our findings demonstrate the efficacy of quantitative proteomics for identifying effector-host protein interactions and suggest that vesicular trafficking is a crucial cellular process that may be targeted by NleB1 and EspL through their interaction with ensconsin.


Assuntos
Proteínas de Escherichia coli/metabolismo , Escherichia coli/patogenicidade , Interações Hospedeiro-Patógeno , Sistemas de Secreção Tipo III/metabolismo , Fatores de Virulência/metabolismo , Linhagem Celular , Humanos , Imunoprecipitação , Espectrometria de Massas , Proteínas Associadas aos Microtúbulos/metabolismo , Ligação Proteica , Sistemas de Secreção Tipo III/química
13.
Am Heart J ; 180: 39-45, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27659881

RESUMO

BACKGROUND: Ischemic heart disease is a major cause of out-of-hospital cardiac arrest. The role of immediate coronary angiography (CAG) and percutaneous coronary intervention (PCI) after restoration of spontaneous circulation following cardiac arrest in the absence of ST-segment elevation myocardial infarction (STEMI) remains debated. HYPOTHESIS: We hypothesize that immediate CAG and PCI, if indicated, will improve 90-day survival in post-cardiac arrest patients without signs of STEMI. DESIGN: In a prospective, multicenter, randomized controlled clinical trial, 552 post-cardiac arrest patients with restoration of spontaneous circulation and without signs of STEMI will be randomized in a 1:1 fashion to immediate CAG and PCI (within 2 hours) versus initial deferral with CAG and PCI after neurological recovery. The primary end point of the study is 90-day survival. The secondary end points will include 90-day survival with good cerebral performance or minor/moderate disability, myocardial injury, duration of inotropic support, occurrence of acute kidney injury, need for renal replacement therapy, time to targeted temperature control, neurological status at intensive care unit discharge, markers of shock, recurrence of ventricular tachycardia, duration of mechanical ventilation, and reasons for discontinuation of treatment. SUMMARY: The COACT trial is a multicenter, randomized, controlled clinical study that will evaluate the effect of an immediate invasive coronary strategy in post-cardiac arrest patients without STEMI on 90-day survival.


Assuntos
Angiografia Coronária , Parada Cardíaca Extra-Hospitalar/terapia , Intervenção Coronária Percutânea , Adulto , Humanos , Análise de Intenção de Tratamento , Parada Cardíaca Extra-Hospitalar/diagnóstico por imagem , Estudos Prospectivos , Projetos de Pesquisa , Tempo para o Tratamento
14.
J Immunol ; 192(6): 2715-21, 2014 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-24554771

RESUMO

Human blood neutrophils normally express two FcγRs (FcγRIIa and FcγRIIIb) that, upon multivalent binding of IgG in immune complexes or on opsonized targets, mediate responses such as phagocytosis, Ab-dependent cellular cytotoxicity, and respiratory burst. Allelic variants have been described for both FcγRIIa (131H/R) and FcγRIIIb (NA1/NA2/SH), with different binding affinity for IgG subclasses. Because neither of these variants acts alone, we have set out to systematically analyze in a large cohort of healthy FCGR2/3-genotyped volunteers how the different haplotypes of neutrophil FcγRs functionally interact. Maximal IgG-induced H2O2 production by neutrophils from individuals with different (homozygous) haplotypes was observed in the following order: 131HH-NA2NA2 > 131RR-NA1NA1 > 131HH-NA1NA1 > 131RR-NA2NA2. Although FcγRIIa 131H is known to bind IgG1 and IgG2 more avidly, no such differences in affinity are known for FcγRIIIb variants. Nonetheless, a remarkable impact of the FcγRIIIb variants on IgG-mediated neutrophil activity was thus demonstrated, which was not explained by differences in FcγR surface expression. The FcγR expression profile was changed by overnight G-CSF/IFN-γ activation of the neutrophils and eliminated any haplotypic impact on the respiratory burst. To our knowledge, our results are the first to provide an integrated functional analysis of neutrophil FcγR haplotypes and suggest that particularly the early phase of IgG-mediated neutrophil reactivity is influenced by FCGR2/3 genotypic variation.


Assuntos
Haplótipos , Imunoglobulina G/imunologia , Neutrófilos/imunologia , Polimorfismo Genético , Receptores de IgG/genética , Células Cultivadas , Citometria de Fluxo , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Frequência do Gene , Genótipo , Fator Estimulador de Colônias de Granulócitos/farmacologia , Humanos , Peróxido de Hidrogênio/metabolismo , Imunoglobulina G/metabolismo , Interferon gama/farmacologia , NADPH Oxidases/metabolismo , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Receptores de IgG/metabolismo
15.
J Immunol ; 188(3): 1318-24, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-22198951

RESUMO

The balance between activating and inhibitory signals from the different FcγRs for IgG ensures homeostasis of many inflammatory responses. FCGR2C is the product of an unequal crossover of the FCGR2A and FCGR2B genes encoding the activating FcγRIIa (CD32a) and inhibitory FcγRIIb (CD32b), respectively. A single nucleotide polymorphism (SNP) in exon 3 of FCGR2C results in either expression of the activating FcγRIIc (CD32c) (FCGR2C-open reading frame [ORF]) or its absence because of a stop codon (FCGR2C-Stop). Two additional variations in FcγRIIb/c expression on leukocytes have now been identified. In case of "nonclassical" FCGR2C-ORF alleles, FcγRIIc expression was unexpectedly absent, because of novel splice site mutations near exon 7 leading to another stop codon. In some individuals with FCGR2C-Stop alleles FcγRIIb was detected on NK cells, which normally are devoid of this protein. Individuals with these nonclassical FCGR2C-Stop alleles carried a deletion of FCGR2C-FCGR3B that extends into the promoter region of the adjacent FCGR2B gene and probably deletes a negative regulatory element in the FCGR2B promoter in NK cells. FcγRIIb expression on NK cells effectively inhibited killing mediated by FcγRIIIa (CD16a) in Ab-dependent cytotoxicity tests. Our findings demonstrate a more extensive and previously unnoticed variation in FcγR expression with relevance to immunity and inflammation.


Assuntos
Alelos , Polimorfismo de Nucleotídeo Único , Receptores de IgG/genética , Regulação da Expressão Gênica/imunologia , Homeostase/imunologia , Humanos , Inflamação/genética , Células Matadoras Naturais/imunologia , Fenótipo , Receptores de IgG/biossíntese
16.
J Allergy Clin Immunol ; 131(5): 1408-16.e5, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23545275

RESUMO

BACKGROUND: Our index case was a patient with common variable immunodeficiency (CVID). She had anaphylactoid reactions on administration of intravenous immunoglobulin (IVIg) associated with the presence of IgG antibodies against IgA. OBJECTIVE: We sought to determine the role of Fcγ receptor (FcγR) IIa in IVIg-induced anaphylactoid reactions. METHODS: Neutrophils and PBMCs were isolated from healthy subjects and IVIg-treated patients. FcγRIIa mRNA and DNA were analyzed by using real-time PCR and sequencing. IgG-mediated elastase release and intracellular Ca(2+) mobilization were determined in neutrophils and transfected cell lines, respectively. RESULTS: A novel splice variant of FcγRIIa containing an expressed cryptic exon 6* (FcγRIIa(exon6∗)) was identified in our index patient. This exon is normally spliced out of all FcγRII isoforms, except the inhibitory FcγRIIb1. Compared with healthy control subjects, the heterozygous FCGR2A(c.742+871A>G) mutation was more frequent in patients with CVID (n = 53, P < .013). Expression in patients with CVID was associated with anaphylaxis on IVIg infusion (P = .002). On screening of additional IVIg-treated patient cohorts, we identified 6 FCGR2A(c.742+871A>G) allele-positive patients with Kawasaki disease (n = 208) and 1 patient with idiopathic thrombocytopenia (n = 93). None had adverse reactions to IVIg. Moreover, FcγRIIa(exon6∗) was also demonstrated in asymptomatic family members. Functional studies in primary cells and transfected murine cells demonstrated enhanced cellular activation by FcγRIIa(exon6∗) compared with its native form, as shown by increased elastase release and intracellular calcium mobilization. CONCLUSION: A novel splice variant, FcγRIIa(exon6∗), was characterized as a low-frequency allele, coding for a gain-of-function receptor for IgG. In the presence of immune complexes, FcγRIIa(exon6∗) can contribute to anaphylaxis in patients with CVID.


Assuntos
Agamaglobulinemia/genética , Anafilaxia/genética , Isoformas de Proteínas/imunologia , Receptores de IgG/genética , Adulto , Agamaglobulinemia/etiologia , Agamaglobulinemia/imunologia , Anafilaxia/complicações , Anafilaxia/imunologia , Animais , Feminino , Humanos , Masculino , Camundongos , Neutrófilos/imunologia , Neutrófilos/patologia , Fatores de Risco
17.
Eur Heart J Acute Cardiovasc Care ; 13(6): 484-492, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38652269

RESUMO

AIMS: When out-of-hospital cardiac arrest (OHCA) becomes refractory, extracorporeal cardiopulmonary resuscitation (ECPR) is a potential option to restore circulation and improve the patient's outcome. However, ECPR requires specific materials and highly skilled personnel, and it is unclear whether increased survival and health-related quality of life (HRQOL) justify these costs. METHODS AND RESULTS: This cost-effectiveness study was part of the INCEPTION study, a multi-centre, pragmatic randomized trial comparing hospital-based ECPR to conventional CPR (CCPR) in patients with refractory OHCA in 10 cardiosurgical centres in the Netherlands. We analysed healthcare costs in the first year and measured HRQOL using the EQ-5D-5L at 1, 3, 6, and 12 months. Incremental cost-effectiveness ratios (ICERs), cost-effectiveness planes, and acceptability curves were calculated. Sensitivity analyses were performed for per-protocol and as-treated subgroups as well as imputed productivity loss in deceased patients. In total, 132 patients were enrolled: 62 in the CCPR and 70 in the ECPR group. The difference in mean costs after 1 year was €5109 (95% confidence interval -7264 to 15 764). Mean quality-adjusted life year (QALY) after 1 year was 0.15 in the ECPR group and 0.11 in the CCPR group, resulting in an ICER of €121 643 per additional QALY gained. The acceptability curve shows that at a willingness-to-pay threshold of €80.000, the probability of ECPR being cost-effective compared with CCPR is 36%. Sensitivity analysis showed increasing ICER in the per-protocol and as-treated groups and lower probabilities of acceptance. CONCLUSION: Hospital-based ECPR in refractory OHCA has a low probability of being cost-effective in a trial-based economic evaluation.


Assuntos
Reanimação Cardiopulmonar , Análise Custo-Benefício , Parada Cardíaca Extra-Hospitalar , Qualidade de Vida , Humanos , Parada Cardíaca Extra-Hospitalar/terapia , Parada Cardíaca Extra-Hospitalar/economia , Masculino , Reanimação Cardiopulmonar/economia , Reanimação Cardiopulmonar/métodos , Feminino , Países Baixos , Pessoa de Meia-Idade , Oxigenação por Membrana Extracorpórea/economia , Oxigenação por Membrana Extracorpórea/métodos , Idoso , Anos de Vida Ajustados por Qualidade de Vida , Taxa de Sobrevida/tendências
18.
Resusc Plus ; 19: 100669, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38873275

RESUMO

Background: Prospective, trial-based data comparing health-related quality of life (HRQoL) in patients surviving out-of-hospital cardiac arrest (OHCA) through extracorporeal cardiopulmonary resuscitation (ECPR) or conventional CPR (CCPR) are scarce. We aimed to determine HRQoL during 1-year after refractory OHCA in patients treated with ECPR and CCPR. Methods: We present a secondary analysis of the multicenter INCEPTION-trial, which studied the effectiveness of ECPR versus CCPR in patients with refractory OHCA. HRQoL was prospectively assessed using the EQ-5D-5L questionnaire. Poor HRQoL was pragmatically defined as an EQ-5D-5L health utility index (HUI) > 1 SD below the age-adjusted norm. We used mixed linear models to assess the difference in HRQoL over time and univariable analyses to assess factors potentially associated with poor HRQoL. Results: A total of 134 patients were enrolled, and hospital survival was 20% (27 patients). EQ-5D-5L data were available for 25 patients (5 ECPR and 20 CCPR). One year after OHCA, the estimated mean HUI was 0.73 (0.05) in all patients, 0.84 (0.12) in ECPR survivors, and 0.71 (0.05) in CCPR survivors (p-value 0.31). Eight (32%) survivors had a poor HRQoL. HRQoL was good in 17 (68%) patients, with 100% in ECPR survivors versus 60% in CCPR survivors (p-value 0.14). Conclusion: One year after refractory OHCA, 68% of the survivors had a good HRQoL. We found no statistically significant difference in HRQoL one year after OHCA in patients treated with ECPR compared to CCPR. However, numerical differences may be clinically relevant in favor of ECPR.

19.
Resusc Plus ; 18: 100657, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38778803

RESUMO

Introduction: Extracorporeal cardiopulmonary resuscitation (ECPR) is increasingly used as a supportive treatment for refractory out-of-hospital cardiac arrest (OHCA). Still, there is a paucity of data evaluating favorable and unfavorable prognostic characteristics in patients considered for ECPR. Methods: We performed a previously unplanned post-hoc analysis of the multicenter randomized controlled INCEPTION-trial. The study group consisted of patients receiving ECPR, irrespective of initial group randomization. The patients were divided into favorable survivors (cerebral performance category [CPC] 1-2) and unfavorable or non-survivors (CPC 3-5). Results: In the initial INCEPTION-trial, 134 patients were randomized. ECPR treatment was started in 46 (66%) of 70 patients in the ECPR treatment arm and 3 (4%) of 74 patients in the conventional treatment arm. No statistically significant differences in baseline characteristics, medical history, or causes of arrest were observed between survivors (n = 5) and non-survivors (n = 44). More patients in the surviving group had a shockable rhythm at the time of cannulation (60% vs. 14%, p = 0.037), underwent more defibrillation attempts (13 vs. 6, p = 0.002), and received higher dosages of amiodarone (450 mg vs 375 mg, p = 0.047) despite similar durations of resuscitation maneuvers. Furthermore, non-survivors more frequently had post-ECPR implantation adverse events. Conclusion: The persistence of ventricular arrhythmia is a favorable prognostic factor in patients with refractory OHCA undergoing an ECPR-based treatment. Future studies are warranted to confirm this finding and to establish additional prognostic factors.Clinical trial Registration:clinicaltrials.gov registration number NCT03101787.

20.
J Biol Chem ; 286(27): 24023-35, 2011 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-21566117

RESUMO

Gram-negative bacterial pathogens have developed specialized secretion systems to transfer bacterial proteins directly into host cells. These bacterial effectors are central to virulence and reprogram host cell processes to favor bacterial survival, colonization, and proliferation. Knowing the complete set of effectors encoded by a particular pathogen is the key to understanding bacterial disease. In addition, the identification of the molecular assemblies that these effectors engage once inside the host cell is critical to determining the mechanism of action of each effector. In this work we used stable isotope labeling of amino acids in cell culture (SILAC), a powerful quantitative proteomics technique, to identify the proteins secreted by the Salmonella pathogenicity island-2 type three secretion system (SPI-2 T3SS) and to characterize the host interaction partners of SPI-2 effectors. We confirmed many of the known SPI-2 effectors and were able to identify several novel substrate candidates of this secretion system. We verified previously published host protein-effector binding pairs and obtained 11 novel interactions, three of which were investigated further and confirmed by reciprocal co-immunoprecipitation. The host cell interaction partners identified here suggest that Salmonella SPI-2 effectors target, in a concerted fashion, cellular processes such as cell attachment and cell cycle control that are underappreciated in the context of infection. The technology outlined in this study is specific and sensitive and serves as a robust tool for the identification of effectors and their host targets that is readily amenable to the study of other bacterial pathogens.


Assuntos
Proteínas de Bactérias/metabolismo , Sistemas de Secreção Bacterianos/fisiologia , Ilhas Genômicas/fisiologia , Interações Hospedeiro-Patógeno/fisiologia , Proteínas de Membrana/metabolismo , Salmonella typhimurium/fisiologia , Salmonella typhimurium/patogenicidade , Proteínas de Bactérias/genética , Humanos , Proteínas de Membrana/genética
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