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Objectives. Temporary mechanical circulatory support (TMCS) has become a component in the therapeutic strategy for treatment of cardiogenic shock as a bridge-to-decision. TMCS can facilitate recovery of cardiopulmonary function, end-organ function, and potentially reduce the surgical risk of left ventricular assist device (LVAD) implantation. Despite the improvements of hemodynamics and end-organ function, post-LVAD operative morbidity might be increased in these high-risk patients. The aim of the study was to compare outcomes after Heartmate 3 (HM3) implantation in patients with and without TMCS prior to HM3 implant. Methods. In this retrospective cohort study of all HM3 patients in the period between November 2015 and October 2021, patients with and without prior TMCS were compared. Patients' demographics, baseline clinical characteristics, laboratory tests, intraoperative variables, postoperative outcomes, and adverse events were collected from patient records. Results. The TMCS group showed an improvement in hemodynamics prior to LVAD implantation. Median TMCS duration was 19.5 (14-26) days. However, the TMCS group were more coagulopathic, had more wound infections, neurological complications, and more patients were on dialysis compared with patient without TMCS prior to HM3 implantation. Survival four years after HM3 implantation was 80 and 82% in the TMCS (N = 22) and non-TMCS group (N = 41), respectively. Conclusion. Patients on TMCS had an acceptable short and long-term survival and comparable to patients receiving HM3 without prior TMCS. However, they had a more complicated postoperative course.
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Insuficiência Cardíaca , Coração Auxiliar , Hemodinâmica , Recuperação de Função Fisiológica , Choque Cardiogênico , Função Ventricular Esquerda , Humanos , Estudos Retrospectivos , Masculino , Feminino , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento , Choque Cardiogênico/fisiopatologia , Choque Cardiogênico/mortalidade , Choque Cardiogênico/terapia , Choque Cardiogênico/diagnóstico , Fatores de Risco , Adulto , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/terapia , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/diagnóstico , Idoso , Implantação de Prótese/instrumentação , Implantação de Prótese/efeitos adversos , Implantação de Prótese/mortalidade , Medição de Risco , Desenho de PróteseRESUMO
The number of lung transplantations is limited due to the shortage of donor lungs fulfilling the standard criteria. The ex vivo lung perfusion (EVLP) technique provides the ability of re-evaluating and potentially improving and treating marginal donor lungs. Accordingly, the technique has emerged as an essential tool to increase the much-needed donor lung pool. One of the major EVLP protocols, the Lund protocol, characterized by high pulmonary artery flow (100% of cardiac output [CO]), an open atrium, and a cellular perfusate, has demonstrated encouraging short-EVLP duration results. However, the potential of the longer EVLP duration of the protocol is yet to be investigated, a duration which is considered necessary to rescue more marginal donor lungs in future. This study aimed to achieve stable 8-h EVLP using an open-atrium cellular model with three different pulmonary artery flows in addition to determining the most optimal flow in terms of best lung performance, including lung electrolytes and least lung edema formation, perfusate and tissue inflammation, and histopathological changes, using the porcine model. EVLP was performed using a flow of either 40% (n = 6), 80% (n = 6), or 100% (n = 6) of CO. No flow rate demonstrated stable 8-h EVLP. Stable 2-h EVLP was observed in all three groups. Insignificant deterioration was observed in dynamic compliance, peak airway pressure, and oxygenation between the groups. Pulmonary vascular resistance increased significantly in the 40% group (p < .05). Electrolytes demonstrated an insignificant worsening trend with longer EVLP. Interleukin-8 (IL-8) in perfusate and tissue, wet-to-dry weight ratio, and histopathological changes after EVLP were insignificantly time dependent between the groups. This study demonstrated that stable 8-h EVLP was not feasible in an open-atrium cellular model regardless of the flow of 40%, 80%, or 100% of CO. No flow was superior in terms of lung performance, lung electrolytes changes, least lung edema formation, minimal IL-8 expression in perfusate and tissue, and histopathological changes.
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Ex vivo lung perfusion (EVLP) has demonstrated encouraging short- and medium-term outcomes with limited data available on its long-term outcomes. This study assesses (1) EVLP long-term outcomes and (2) EVLP era-based sub-analysis in addition to secondary outcomes of recipients with EVLP-treated donor lungs compared with recipients of conventionally preserved donor lungs in unmatched and propensity score-matched cohorts. Double lung transplants performed between 1st January 2012 and 31st December 2021 were included. A total of 57 recipients received EVLP-treated lungs compared to 202 unmatched and 57 matched recipients who were subjected to non-EVLP-treated lungs. The EVLP group had a significantly lower mean PaO2/FiO2 ratio and significantly higher mean BMI than the non-EVLP group in the unmatched and matched cohorts. The proportion of smoking history in the unmatched cohort was significantly higher in the EVLP group, while a similar smoking history was demonstrated in the matched cohorts. No difference was demonstrated in overall freedom from death and retransplantation between the groups in the unmatched and matched cohorts (unmatched: hazard ratio (HR) 1.28, 95% confidence interval (CI) 0.79-2.07, P = 0.32; matched: HR 1.06, 95% CI 0.59-1.89). P = 0.89). In the unmatched cohort, overall freedom from chronic allograft dysfunction (CLAD) was significantly different between the groups (HR 1.64, 95% CI 1.07-2.52, P = 0.02); however, the cumulative CLAD incidence was similar (HR 0.72, 95% CI 0.48-1.1, P = 0.13). In the matched cohort, the overall freedom from CLAD (HR 1.69, 95% CI 0.97-2.95, P = 0.06) and cumulative CLAD incidence (HR 0.91, 95% CI 0.37-2.215, P = 0.83) were similar between the groups. The EVLP era sub-analysis of the unmatched cohort in 2012-2014 had a significantly higher cumulative CLAD incidence in the EVLP group; however, this was not demonstrated in the matched cohort. All secondary outcomes were similar between the groups in the unmatched and matched cohorts. In conclusion, transplantation of marginal donor lungs after EVLP evaluation is non-detrimental compared to conventionally preserved donor lungs in terms of mortality, retransplantation, cumulative CLAD incidence, and secondary outcomes. Although the unmatched EVLP era of 2012-2014 had a significantly higher cumulative CLAD incidence, no such finding was demonstrated in the matched cohort of the same era.
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AIMS: Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) are increasingly used to treat type 2 diabetes and obesity. Albeit cardiovascular outcomes generally improve, treatment with GLP-1 RAs is associated with increased heart rate, the mechanism of which is unclear. METHODS AND RESULTS: We employed a large animal model, the female landrace pig, and used multiple in-vivo and ex-vivo approaches including pharmacological challenges, electrophysiology and high-resolution mass spectrometry to explore how GLP-1 elicits an increase in heart rate. In anaesthetized pigs, neither cervical vagotomy, adrenergic blockers (alpha, beta or combined alpha-beta blockade), ganglionic blockade (hexamethonium) nor inhibition of hyperpolarization-activated cyclic nucleotide-gated (HCN) channels (ivabradine) abolished the marked chronotropic effect of GLP-1. GLP-1 administration to isolated perfused pig hearts also increased heart rate, which was abolished by GLP-1 receptor blockade. Electrophysiological characterization of GLP-1 effects in vivo and in isolated perfused hearts localized electrical modulation to the atria and conduction system. In isolated sinus nodes, GLP-1 administration shortened action potential cycle length of pacemaker cells and shifted the site of earliest activation. The effect was independent of HCN blockade. Collectively, these data support a direct effect of GLP-1 on GLP-1 receptors within the heart. Consistently, single nucleus RNA sequencing (snRNAseq) showed GLP-1 receptor expression in porcine pacemaker cells. Quantitative phosphoproteomics analyses of sinus node samples revealed that GLP-1 administration leads to phosphorylation changes of calcium cycling proteins of the sarcoplasmic reticulum, known to regulate heart rate. CONCLUSION: GLP-1 has direct chronotropic effects on the heart mediated by GLP-1 receptors in pacemaker cells of the sinus node, inducing changes in action potential morphology and the leading pacemaker site through a calcium signaling response characterized by PKA-dependent phosphorylation of Ca2+ cycling proteins involved in pace making. Targeting the pacemaker calcium clock may be a strategy to lower heart rate in GLP-1 RA recipients.
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The standard Conventional Cold Storage (CCS) during heart transplantation procurement is associated with time-dependent ischemic injury to the graft, which is a significant independent risk factor for post-transplant early morbidity and mortality - especially when cold ischemic time exceeds four hours. Since 2018, Rigshospitalet (Copenhagen, Denmark) has been utilising ex vivo perfusion (Organ Care System, OCS) in selected cases. The objective of this study was to compare the short-term clinical outcomes of patients transplanted with OCS compared to CCS. Methods: This retrospective single-centre study was based on consecutive patients undergoing a heart transplant between January 2018 and April 2021. Patients were selected for the OCS group when the cold ischemic time was expected to exceed four hours. The primary outcome measure was six-month event-free survival. Results: In total, 48 patients were included in the study; nine were transplanted with an OCS heart. The two groups had no significant differences in baseline characteristics. Six-month event-free survival was 77.8% [95% CI: 54.9-100%] in the OCS group and 79.5% [95% CI: 67.8-93.2%] in the CCS group (p = 0.91). While the OCS group had a median out-of-body time that was 183 min longer (p < 0.0001), the cold ischemic time was reduced by 51 min (p = 0.007). Conclusion: In a Scandinavian setting, our data confirms that utilising OCS in heart procurement allows for a longer out-of-body time and a reduced cold ischemic time without negatively affecting safety or early post-transplant outcomes.
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Transplante de Coração , Humanos , Transplante de Coração/efeitos adversos , Doadores de Tecidos , Estudos Retrospectivos , Preservação de Órgãos/efeitos adversos , Perfusão/efeitos adversosRESUMO
The regulation of microRNA (miRNA) biogenesis is crucial for maintaining plant homeostasis under biotic and abiotic stress. The crosstalk between the RNA polymerase II (Pol-II) complex and the miRNA processing machinery has emerged as a central hub modulating transcription and cotranscriptional processing of primary miRNA transcripts (pri-miRNAs). However, it remains unclear how miRNA-specific transcriptional regulators recognize MIRNA loci. Here, we show that the Arabidopsis (Arabidopsis thaliana) HIGH EXPRESSION OF OSMOTICALLY RESPONSIVE GENE15 (HOS15)-HISTONE DEACETYLASE9 (HDA9) complex is a conditional suppressor of miRNA biogenesis, particularly in response to abscisic acid (ABA). When treated with ABA, hos15/hda9 mutants show enhanced transcription of pri-miRNAs that is accompanied by increased processing, leading to overaccumulation of a set of mature miRNAs. Moreover, upon recognition of the nascent pri-miRNAs, the ABA-induced recruitment of the HOS15-HDA9 complex to MIRNA loci is guided by HYPONASTIC LEAVES 1 (HYL1). The HYL1-dependent recruitment of the HOS15-HDA9 complex to MIRNA loci suppresses expression of MIRNAs and processing of pri-miRNA. Most importantly, our findings indicate that nascent pri-miRNAs serve as scaffolds for recruiting transcriptional regulators, specifically to MIRNA loci. This indicates that RNA molecules can act as regulators of their own expression by causing a negative feedback loop that turns off their transcription, providing a self-buffering system.
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Proteínas de Arabidopsis , Arabidopsis , MicroRNAs , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Histonas/metabolismo , Ácido Abscísico/farmacologia , Ácido Abscísico/metabolismo , Proteínas de Ligação a RNA/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Processamento Pós-Transcricional do RNA , Regulação da Expressão Gênica de Plantas , Histona Desacetilases/genética , Histona Desacetilases/metabolismoRESUMO
INTRODUCTION: Since 2007, transcatheter aortic valve implantation (TAVI) has emerged as another treatment strategy for severe symptomatic aortic stenosis (AS) compared with surgical aortic valve replacement (SAVR). The objectives were to compare annual rates of aortic valve replacement (AVR) procedures performed in Denmark in the era of TAVI and to assess proportion of AVRs stratified by age with use of age recommendations presented in current guidelines. METHODS: Using Danish nationwide registries, we identified first-time AVRs between 2008 and 2020. Patients who were not diagnosed with AS prior to AVR were excluded RESULTS: The rate of AVRs increased by 39% per million inhabitants from 2008 to 2020. TAVI has steadily increased since 2008, accounting for 64.2% of all AVRs and 72.5% of isolated AVRs by 2020. Number of isolated SAVRs decreased from 2014 and onwards. The proportion of TAVI increased significantly across age groups (<75 and ≥75 years of age, ptrend<0.001), and TAVI accounted for 91.5% of isolated AVR procedures in elderly patients (aged ≥75 years). Length of hospital stay were significantly reduced for all AVRs during the study period (ptrend all<0.001). CONCLUSIONS: The number of AVRs increased from 2008 to 2020 due to adaptation of TAVI, which represented 2/3 of AVRs and more than 70% of isolated AVRs. In elderly patients, the increased use of AVR procedures was driven by TAVI, in agreement with the age recommendations in current guidelines; however, TAVI was used more frequently in patients aged <75 years, accompanied by a flattening use of SAVR.
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Estenose da Valva Aórtica , Implante de Prótese de Valva Cardíaca , Substituição da Valva Aórtica Transcateter , Idoso , Humanos , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/cirurgia , Fatores de Risco , Substituição da Valva Aórtica Transcateter/efeitos adversos , Implante de Prótese de Valva Cardíaca/métodos , Resultado do Tratamento , DinamarcaRESUMO
The TACSI trial (ClinicalTrials.gov Identifier: NCT03560310) tests the hypothesis that 1-year treatment with dual antiplatelet therapy with acetylsalicylic acid (ASA) and ticagrelor is superior to only ASA after isolated coronary artery bypass grafting (CABG) in patients with acute coronary syndrome. The TACSI trial is an investigator-initiated pragmatic, prospective, multinational, multicenter, open-label, registry-based randomized trial with 1:1 randomization to dual antiplatelet therapy with ASA and ticagrelor or ASA only, in patients undergoing first isolated CABG, with a planned enrollment of 2200 patients at Nordic cardiac surgery centers. The primary efficacy end point is a composite of time to all-cause death, myocardial infarction, stroke, or new coronary revascularization within 12 months after randomization. The primary safety end point is time to hospitalization due to major bleeding. Secondary efficacy end points include time to the individual components of the primary end point, cardiovascular death, and rehospitalization due to cardiovascular causes. High-quality health care registries are used to assess primary and secondary end points. The patients will be followed for 10 years. The TACSI trial will give important information useful for guiding the antiplatelet strategy in acute coronary syndrome patients treated with CABG.
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Síndrome Coronariana Aguda , Intervenção Coronária Percutânea , Humanos , Inibidores da Agregação Plaquetária/uso terapêutico , Ticagrelor/uso terapêutico , Síndrome Coronariana Aguda/tratamento farmacológico , Síndrome Coronariana Aguda/cirurgia , Estudos Prospectivos , Aspirina/uso terapêutico , Ponte de Artéria Coronária , Sistema de Registros , Resultado do TratamentoRESUMO
AIM: To validate a recently proposed risk prediction model for chronic kidney disease (CKD) in type 2 diabetes (T2D). MATERIALS AND METHODS: Subjects from the German/Austrian Diabetes Prospective Follow-up (DPV) registry with T2D, normoalbuminuria, an estimated glomerular filtration rate of 60 ml/min/1.73m2 or higher and aged 39-75 years were included. Prognostic factors included age, body mass index (BMI), smoking status and HbA1c. Subjects were categorized into low, moderate, high and very high-risk groups. Outcome was CKD occurrence. RESULTS: Subjects (n = 10 922) had a mean age of 61 years, diabetes duration of 6 years, BMI of 31.7 kg/m2 , HbA1c of 6.9% (52 mmol/mol); 9.1% had diabetic retinopathy and 16.3% were smokers. After the follow-up (~59 months), 37.4% subjects developed CKD. The area under the curve (AUC; unadjusted base model) was 0.58 (95% CI 0.57-0.59). After adjustment for diabetes and follow-up duration, the AUC was 0.69 (95% CI 0.68-0.70), indicating improved discrimination. After follow-up, 15.0%, 20.1%, 27.7% and 40.2% patients in the low, moderate, high and very high-risk groups, respectively, had developed CKD. Increasing risk score correlated with increasing cumulative risk of incident CKD over a median of 4.5 years of follow-up (P < .0001). CONCLUSIONS: The predictive model achieved moderate discrimination but good calibration in a German/Austrian T2D population, suggesting that the model may be relevant for determining CKD risk.
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Diabetes Mellitus Tipo 2 , Insuficiência Renal Crônica , Humanos , Pessoa de Meia-Idade , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Seguimentos , Hemoglobinas Glicadas , Estudos Prospectivos , Áustria/epidemiologia , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/epidemiologia , Fatores de Risco , Taxa de Filtração Glomerular , Sistema de RegistrosRESUMO
We aimed to investigate a hypothesised association between daily mean temperature and the risk of surgery for acute type A aortic dissection (ATAAD). For the period of 1 January 2005 until 31 December 2019, we collected daily data on mean temperatures and date of 2995 operations for ATAAD at 10 Nordic cities included in the Nordic Consortium for Acute Type A Aortic Dissection (NORCAAD) collaboration. Using a two-stage time-series approach, we investigated the association between hot and cold temperatures relative to the optimal temperature and the rate of ATAAD repair in the selected cities. The relative risks (RRs) of cold temperatures (≤-5°C) and hot temperatures (≥21°C) compared to optimal temperature were 1.47 (95% CI: 0.72-2.99) and 1.43 (95% CI: 0.67-3.08), respectively. In line with previous studies, we observed increased risk at cold and hot temperatures. However, the observed associations were not statistically significant, thus only providing weak evidence of an association.
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Aneurisma Aórtico , Dissecção Aórtica , Humanos , Aneurisma Aórtico/epidemiologia , Aneurisma Aórtico/cirurgia , Incidência , Temperatura , Estudos Retrospectivos , Fatores de Risco , Doença Aguda , Resultado do Tratamento , Dissecção Aórtica/epidemiologia , Dissecção Aórtica/cirurgia , Temperatura Alta , Temperatura BaixaRESUMO
The expanding phenomenon of crowdfunding for healthcare creates novel potential roles for members of the public as fundraisers and donors of particular forms of provision. While sometimes interpreted as an empowering phenomenon (Gonzales et al., 2018), or a potentially useful communication of unmet needs (Saleh et al., 2021), scholars have predominantly been critical of the way in which crowdfunding for healthcare normalises unmet needs and exacerbates entrenched inequalities (Berliner and Kenworthy, 2017; Igra et al., 2021; Paulus and Roberts, 2018). We report a thematic analysis of the text of 945 fundraising appeals created on JustGiving and GoFundMe in the first months of the COVID-19 pandemic, where the recipient was NHS Charities Together's dramatically successful COVID-19 Urgent Appeal. Unlike in existing accounts of individual healthcare crowdfunding, we identify the relative absence of both coherent problem definition and of a fundable solution within the pages. Instead, appeals are dominated by themes of solidarity and duty during the UK's 'hard' lockdown of 2020. A national appeal reduces the risks of crowdfunding exacerbating existing health inequalities, but we argue that two kinds of non-financial consequences of collective crowdfunding require further exploration. Specifically, we need to better understand how expanded practices of fundraising co-exist with commitment to dutiful, means-based funding of healthcare via taxation. We must also attend to how celebration of the NHS as a national achievement, might squeeze spaces for critique and challenge. Analyses of crowdfunding need to explore both financial and non-financial aspects of practices within different health system and historical contexts.
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COVID-19 , Crowdsourcing , COVID-19/epidemiologia , Controle de Doenças Transmissíveis , Financiamento da Assistência à Saúde , Humanos , Pandemias , Medicina Estatal , Reino Unido/epidemiologiaRESUMO
Objectives. Heart transplantation (HTx) has become an established treatment option in patients with end-stage heart failure. The aim of this study was to report on long-term outcome over the past three decades. Design. Consecutive adult patients receiving first-time and isolated HTx from October 3, 1990, to November 2, 2020, at Rigshospitalet, Copenhagen, Denmark, were retrospectively evaluated. Data were obtained from the Scandinavian Transplant Registry and patient medical records. Recipients were grouped by time of transplantation (early era: 1990-1999; mid era: 2000-2009; recent era: 2010-2020). Results. A total of 384 recipients (77% men, median age 50 [IQR: 40-57]) were included. Median number of HTx procedures per year was 12 (10-14). Overall, 22% of patients were bridged to HTx with a mechanical circulatory support device. Median survival for the whole cohort was 13.8 years and improved numerically from the early era (12.6 years) to the mid era (14.9 years). Median survival conditional on survival to 1-year follow-up after HTx was 16.1 years. Survival probability by Kaplan-Meier method improved significantly from the mid to the recent era (log-rank p = .02). Conclusions. Heart transplantation remains an excellent treatment for selected patients with end-stage heart failure and long-term outcome has improved significantly over the past decades.
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Insuficiência Cardíaca , Transplante de Coração , Adulto , Feminino , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Estudos RetrospectivosRESUMO
BACKGROUND: Patients undergoing lung transplantation (LTx) experience a rapid decline in glomerular filtration rate (GFR) in the acute postoperative period. However, no prospective longitudinal studies directly comparing the performance of equations for estimating GFR in this patient population currently exist. METHODS: In total, 32 patients undergoing LTx met the study criteria. At pre-LTx and 1-, 3-, and 12-weeks post-LTx, GFR was determined by 51Cr-EDTA and by equations for estimating GFR based on plasma (P)-Creatinine, P-Cystatin C, or a combination of both. RESULTS: Measured GFR declined from 98.0 mL/min/1.73 m2 at pre-LTx to 54.1 mL/min/1.73 m2 at 12-weeks post-LTx. Equations based on P-Creatinine underestimated GFR decline after LTx, whereas equations based on P-Cystatin C overestimated this decline. Overall, the 2021 CKD-EPI combination equation had the lowest bias and highest precision at both pre-LTx and post-LTx. CONCLUSIONS: Caution must be applied when interpreting renal function based on equations for estimating GFR in the acute postoperative period following LTx. Simplified methods for measuring GFR may allow for more widespread use of measured GFR in this vulnerable patient population.
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BACKGROUND: Lungs from donation after circulatory death (DCD) may be an underused resource for transplantation. The aim was to investigate, with a DCD pig model, if it was possible to recondition lungs exposed for up to 2 h of warm ischaemia with ex vivo lung perfusion (EVLP). METHODS: Danish domestic pigs (N = 17) were randomized into three groups. In the two study groups, lungs were exposed to either 1 or 2 h of warm ischaemia. All lungs were reconditioned and evaluated after 83 ± 38 minutes of perfusion at FiO2 1.0 and 0.21 with EVLP. Outcome measures were gas exchange, pulmonary physiology, inflammatory markers, and histopathologic assessment score. RESULTS: Lungs exposed for 2 h of warm ischaemia did not meet the criteria: PaO2 > 13 kPa required for donation compared with lungs subjected to 0 and 1 h of warm ischaemia (11.0 kPa vs. 14.2 kPa, P < 0.001). These lungs also developed an increased amount of foam and fluid in the airways. No differences in PaCO2, compliance, or pulmonary vascular resistance were observed. CONCLUSION: Results show that while lungs subjected to 0 or 1 h of warm ischaemia meet the criteria for transplantation based on EVLP evaluation, lungs subjected to 2 h of warm ischaemia did not.
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Transplante de Pulmão , Isquemia Quente , Animais , Circulação Extracorpórea , Pulmão , Transplante de Pulmão/métodos , Perfusão/métodos , Suínos , Isquemia Quente/métodosRESUMO
The core plant microprocessor consists of DICER-LIKE 1 (DCL1), SERRATE (SE), and HYPONASTIC LEAVES 1 (HYL1) and plays a pivotal role in microRNA (miRNA) biogenesis. However, the proteolytic regulation of each component remains elusive. Here, we show that HYL1-CLEAVAGE SUBTILASE 1 (HCS1) is a cytoplasmic protease for HYL1-destabilization. HCS1-excessiveness reduces HYL1 that disrupts miRNA biogenesis, while HCS1-deficiency accumulates HYL1. Consistently, we identified the HYL1K154A mutant that is insensitive to the proteolytic activity of HCS1, confirming the importance of HCS1 in HYL1 proteostasis. Moreover, HCS1-activity is regulated by light/dark transition. Under light, cytoplasmic CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1) E3 ligase suppresses HCS1-activity. COP1 sterically inhibits HCS1 by obstructing HYL1 access into the catalytic sites of HCS1. In contrast, darkness unshackles HCS1-activity for HYL1-destabilization due to nuclear COP1 relocation. Overall, the COP1-HYL1-HCS1 network may integrate two essential cellular pathways: the miRNA-biogenetic pathway and light signaling pathway.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , MicroRNAs/metabolismo , Processamento Pós-Transcricional do RNA/fisiologia , Proteínas de Ciclo Celular/metabolismo , Núcleo Celular/metabolismo , Regulação da Expressão Gênica de Plantas/fisiologia , Folhas de Planta/metabolismo , Proteínas de Ligação a RNA/metabolismo , Ubiquitina-Proteína Ligases/metabolismoRESUMO
OBJECTIVES: Acute type A aortic dissection (ATAAD) is a rare but severe condition, routinely treated with emergent cardiac surgery. Many surgeons have the notion that patients with ATAAD tend to come in clusters, but no studies have examined these observations. This investigation was undertaken to study the potential association between the lunar cycle and the incidence of ATAAD. METHODS: We collected information on 2995 patients who underwent ATAAD surgery at centres from the Nordic Consortium for Acute Type A Aortic Dissection collaboration. We cross-referenced the time of surgery with lunar phase using a case-crossover design with 2 different definitions of full moon (>99% illumination and the 7-day full moon period). RESULTS: The period when the moon was illuminated the most (99% definition) did not show any significant increase in incidence for ATAAD surgery. However, when the full moon period was compared with all other moon phases, it yielded a relative risk of 1.08 [95% confidence interval (CI) 1.00-1.17, P = 0.057] and, compared to waxing moon, only the relative risk was 1.11 (95% CI 1.01-1.23, P = 0.027). The peak incidence came 4-6 days after the moon was fully illuminated. CONCLUSIONS: This study found an overrepresentation of surgery for ATAAD during the full moon phase. The explanation for this is not known, but we speculate that sleep deprivation during full moon leads to a temporary increase in blood pressure, which in turn could trigger rupture of the aortic wall. While this finding is interesting, it needs to be corroborated and the clinical implications are debateable.
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Dissecção Aórtica , Lua , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/epidemiologia , Dissecção Aórtica/cirurgia , Estudos Cross-Over , Humanos , Incidência , Estudos Retrospectivos , RiscoRESUMO
Glucagon-like peptide-1 (GLP-1) has proven to be protective in animal models of lung disease but the underlying mechanisms are unclear. Atrial natriuretic peptide (ANP) is mainly produced in the heart. As ANP possesses potent vaso- and bronchodilatory effects in pulmonary disease, we hypothesised that the protective functions of GLP-1 could involve potentiation of local ANP secretion from the lung. We examined whether the GLP-1 receptor agonist liraglutide was able to improve oxygenation in lungs exposed to 2â h of warm ischemia and if liraglutide stimulated ANP secretion from the lungs in the porcine ex vivo lung perfusion (EVLP) model. Pigs were given a bolus of 40â µg/kg liraglutide or saline 1â h prior to sacrifice. The lungs were then left in vivo for 2â h, removed en bloc and placed in the EVLP machinery. Lungs from the liraglutide treated group were further exposed to liraglutide in the perfusion buffer (1.125â mg). Main endpoints were oxygenation capacity, and plasma and perfusate concentrations of proANP and inflammatory markers. Lung oxygenation capacity, plasma concentrations of proANP or concentrations of inflammatory markers were not different between groups. ProANP secretion from the isolated perfused lungs were markedly higher in the liraglutide treated group (area under curve for the first 30â min in the liraglutide group: 635 ± 237 vs. 38 ± 38â pmol/L x min in the saline group) (p < 0.05). From these results, we concluded that liraglutide potentiated local ANP secretion from the lungs.
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INTRODUCTION: Coronary artery bypass grafting (CABG) and/or aortic valve replacement (AVR) are associated with risk of death, as well as brain, heart and kidney injury. Glucagon-like peptide-1 (GLP-1) analogues are approved for treatment of type 2 diabetes, and GLP-1 analogues have been suggested to have potential organ-protective and anti-inflammatory effects. During cardiopulmonary bypass (CPB), consensus on the optimal fraction of oxygen is lacking. The objective of this study is to determine the efficacy of the GLP-1-analogue exenatide versus placebo and restrictive oxygenation (50% fractional inspired oxygen, FiO2) versus liberal oxygenation (100% FiO2) in patients undergoing open heart surgery. METHODS AND ANALYSIS: A randomised, placebo-controlled, double blind (for the exenatide intervention)/single blind (for the oxygenation strategy), 2×2 factorial designed single-centre trial on adult patients undergoing elective or subacute CABG and/or surgical AVR. Patients will be randomised in a 1:1 and 1:1 ratio to a 6-hour and 15 min infusion of 17.4 µg of exenatide or placebo during CPB and to a FiO2 of 50% or 100% during and after weaning from CPB. Patients will be followed until 12 months after inclusion of the last participant. The primary composite endpoint consists of time to first event of death, renal failure requiring renal replacement therapy, hospitalisation for stroke or heart failure. In addition, the trial will include predefined sub-studies applying more advanced measures of cardiac- and pulmonary dysfunction, renal dysfunction and cerebral dysfunction. The trial is event driven and aims at 323 primary endpoints with a projected inclusion of 1400 patients. ETHICS AND DISSEMINATION: Eligible patients will provide informed, written consent prior to randomisation. The trial is approved by the local ethics committee and is conducted in accordance with Danish legislation and the Declaration of Helsinki. The results will be presented in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT02673931.
Assuntos
Diabetes Mellitus Tipo 2 , Peptídeo 1 Semelhante ao Glucagon , Adulto , Valva Aórtica , Ponte de Artéria Coronária , Método Duplo-Cego , Humanos , Oxigênio , Ensaios Clínicos Controlados Aleatórios como Assunto , Método Simples-Cego , Resultado do TratamentoRESUMO
The pathophysiology of Takotsubo syndrome (TTS) is incompletely understood. A sympathetic overdrive with coronary microvascular dysfunction might play a central role. The aim of our study was to assess the status of the systemic microcirculation (MC) of patients with TTS, compared to patients with myocardial infarction (MI) and healthy subjects. The systemic microvascular function of 22 TTS patients, 20 patients with MI and 20 healthy subjects was assessed via sublingual sidestream dark-field imaging. In TTS and MI patients, measurements were performed during the acute phase (day 1, 3 and 5) and after 3 months. The measurement in healthy subjects was performed once. The assessed parameters were number of vessel crossings, number of perfused vessel crossings, proportion of perfused vessels, total vessel density and perfused vessel density. The results did not show relevant differences between the investigated groups. Some minor, albeit statistically significant, differences occurred rather randomly. The MC parameters of the TTS group did not show any relevant changes in the temporal course. A systemic microvascular dysfunction could not be identified as a contributing factor in the pathogenesis of TTS. A possible microvascular dysfunction might instead be caused by a local effect restricted to the coronary microvascular bed.
RESUMO
BACKGROUND: The short- and long-term prognosis of Takotsubo syndrome (TTS) presenting with right ventricular (RV) involvement remains poorly understood. RESEARCH QUESTION: What is the incidence and clinical outcome of RV involvement in TTS? STUDY DESIGN AND METHODS: This study analyzed 839 consecutive patients with TTS (758 female subjects and 81 male subjects) in a multicenter registry. RV involvement was defined as wall motion abnormality of the RV free wall, with or without apical involvement. The median long-term follow-up was 2.1 years (interquartile range, 0.3-4.5 years). The primary outcome was in-hospital and out-of-hospital all-cause mortality. The secondary end point was a composite of in-hospital death, thromboembolic events, cardiogenic shock, pulmonary edema, and malignant arrhythmias. RESULTS: The incidence of RV involvement in TTS was 11% (n = 93). More often patients with RV involvement were male compared with patients without RV involvement (P = .02). There was a slight difference in the left ventricular ejection fraction measured in patients with RV involvement vs those patients with isolated left ventricular TTS (38 ± 10% vs 40 ± 10%; P = .03). No major differences in terms of comorbidities were observed between groups except regarding a history of cancer, which was significantly more prevalent in patients with TTS presenting with RV involvement (P = .03). Physical stressors were more prevalent in the RV group (P < .01), whereas emotional stressors were less prevalent (P < .01). Patients with RV involvement had a higher incidence of in-hospital cardiogenic shock (P = .02). The primary outcome (in- and out-of-hospital all-cause mortality) was observed in 12.8% of patients without RV involvement compared with 29% of patients with RV involvement. Although the in-hospital mortality rate was similar in both groups, a higher out-of-hospital all-cause mortality rate (log-rank test, P = .008) was observed in the RV involvement group. The Cox multivariable regression analysis showed that physical triggers were independent predictors of RV involvement. INTERPRETATION: RV involvement defines a high-risk cohort of patients with TTS. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov; No.: NCT04361994; URL: www.clinicaltrials.gov.