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BACKGROUND: The relationship of serial NT-proBNP (N-terminal pro-B-type natriuretic peptide) measurements with changes in cardiac features and outcomes in heart failure (HF) remains incompletely understood. We determined whether common clinical covariates impact these relationships. METHODS AND RESULTS: In 2 nationwide observational populations with HF, the relationship of serial NT-proBNP measurements with serial echocardiographic parameters and outcomes was analyzed, further stratified by HF with reduced versus preserved left ventricular ejection fraction, inpatient versus outpatient enrollment, age, obesity, chronic kidney disease, atrial fibrillation, and attainment of ≥50% guideline-recommended doses of renin-angiotensin system inhibitors and ß-blockers. Among 1911 patients (mean±SD age, 65.1±13.4 years; 26.6% women; 62% inpatient and 38% outpatient), NT-proBNP declined overall, with more rapid declines among inpatients, those with obesity, those with atrial fibrillation, and those attaining ≥50% guideline-recommended doses. Each doubling of NT-proBNP was associated with increases in left ventricular volume (by 6.1 mL), E/e' (transmitral to mitral annular early diastolic velocity ratio) (by 1.4 points), left atrial volume (by 3.6 mL), and reduced left ventricular ejection fraction (by -2.1%). The effect sizes of these associations were lower among patients with HF with preserved ejection fraction, atrial fibrillation, or advanced age (Pinteraction<0.001). A landmark analysis identified that an SD increase in NT-proBNP over 6 months was associated with a 27% increase in the risk of the composite event of HF hospitalization or all-cause death between 6 months and 2 years (adjusted hazard ratio, 1.27 [95% CI, 1.15-1.40]; P<0.001). CONCLUSIONS: The relationships between NT-proBNP and structural/functional remodeling differed by age, presence of atrial fibrillation, and HF phenotypes. The association of increased NT-proBNP with increased risk of adverse outcomes was consistent in all subgroups.
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Biomarcadores , Insuficiência Cardíaca , Peptídeo Natriurético Encefálico , Fragmentos de Peptídeos , Volume Sistólico , Função Ventricular Esquerda , Humanos , Fragmentos de Peptídeos/sangue , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/fisiopatologia , Feminino , Masculino , Peptídeo Natriurético Encefálico/sangue , Idoso , Pessoa de Meia-Idade , Biomarcadores/sangue , Volume Sistólico/fisiologia , Prognóstico , Ecocardiografia , Estudos Longitudinais , Fatores de Risco , Valor Preditivo dos Testes , Fatores de Tempo , Estados Unidos/epidemiologia , Idoso de 80 Anos ou mais , Remodelação VentricularRESUMO
BACKGROUND: Concomitant cerebrovascular diseases (CeVD) have been identified as an important determinant of Alzheimer's disease (AD) progression. Development of robust blood-based biomarkers will provide critical tools to evaluate prognosis and potential interventional strategies for AD with CeVD. OBJECTIVE: This study investigated circulating placental growth factor (PlGF), a potent pro-angiogenic factor related to endothelial dysfunction and vascular inflammation, in an Asian memory clinic cohort of non-demented individuals as well as AD, including its associations with neuroimaging markers of CeVD. METHODS: 109 patients with AD, 76 cognitively impaired with no dementia (CIND), and 56 non-cognitively impaired (NCI) were included in this cross-sectional study. All subjects underwent 3T brain magnetic resonance imaging to assess white matter hyperintensities (WMH), lacunes, cortical infarcts, and cerebral microbleeds (CMBs). Serum PlGF concentrations were measured by electrochemiluminescence immunoassays. RESULTS: Serum PlGF was elevated in AD, but not CIND, compared to the NCI controls. Adjusted concentrations of PlGF were associated with AD only in the presence of significant CeVD. Elevated PlGF was significantly associated with higher burden of WMH and with CMBs in AD patients. CONCLUSIONS: Serum PlGF has potential utility as a biomarker for the presence of CeVD, specifically WMH and CMBs, in AD. Further studies are needed to elucidate the underlying pathophysiological mechanisms linking PlGF to CeVD, as well as to further assess PlGF's clinical utility.
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Doença de Alzheimer , Transtornos Cerebrovasculares , Disfunção Cognitiva , Substância Branca , Feminino , Humanos , Doença de Alzheimer/patologia , Transtornos Cerebrovasculares/complicações , Disfunção Cognitiva/patologia , Estudos Transversais , Imageamento por Ressonância Magnética/métodos , Fator de Crescimento Placentário , Substância Branca/patologiaRESUMO
BACKGROUND: Limited studies have investigated the association between statin therapy and poor glycemic control, especially in the Chinese diabetic population. METHODS: Two prospective diabetes cohorts were drawn from the Kailuan Cohort. In Cohort 1, linear regression models were used to evaluate the association between statin therapy and glycated hemoglobin (HbA1c) level change. In Cohort 2, new user design and conditional logistic models were used to assess associations between statin initiation and poor glycemic control which was a composite outcome comprised of hypoglycemic agent escalation and new-onset hyperglycemia. RESULTS: Among 11,755 diabetic patients with medication information, 1400 statin users and 1767 statin nonusers with repeated HbA1c measurements were included in Cohort 1 (mean age: 64.6 ± 10.0 years). After a median follow-up of 3.02 (1.44, 5.00) years, statin therapy was associated with higher HbA1c levels (ß: 0.20%; 95%CI: 0.05% to 0.34%). In Cohort 2, 1319 pairs of matched cases/controls were included (mean age: 61.6 ± 9.75 years). After a median follow-up of 4.87 (2.51, 8.42) years, poor glycemic control occurred in 43.0% of statin new users and 31.8% of statin nonusers (OR: 1.69; 95% CI: 1.32 to 2.17; P < 0.001). The statin-associated poor glycemic control risk was significantly higher among patients with lower body mass index (Pint = 0.089). Furthermore, a nonlinear association was observed between statin therapy duration and poor glycemic control (P = 0.003). CONCLUSIONS: Among Chinese diabetic adults, statin therapy was associated with a higher level of HbA1c, and a higher risk of hypoglycemic agent escalation and new-onset hyperglycemia, especially among those who had lower body mass index levels and longer statin therapy duration.
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Glicemia , Hemoglobinas Glicadas , Controle Glicêmico , Inibidores de Hidroximetilglutaril-CoA Redutases , Humanos , Masculino , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Feminino , Pessoa de Meia-Idade , China/epidemiologia , Hemoglobinas Glicadas/metabolismo , Estudos Prospectivos , Glicemia/metabolismo , Glicemia/efeitos dos fármacos , Controle Glicêmico/métodos , Fatores de Risco , Idoso , Hipoglicemiantes/uso terapêutico , Seguimentos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/sangue , Hiperglicemia/epidemiologia , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/sangue , Biomarcadores/sangue , Medição de Risco/métodos , População do Leste AsiáticoRESUMO
Background: Heart failure and left ventricular ejection fraction in the normal range (HFnEF) (left ventricular ejection fraction [LVEF] of ≥55% for men and ≥60% for women) is understudied. Objectives: The authors aimed to characterize patients with HFnEF compared with those with preserved (≥50%) yet below the normal LVEF. Methods: In an Asian HF registry, clinical characteristics, echocardiographic features, and outcomes were compared across: 1) HFnEF; 2) heart failure with preserved left ventricular ejection fraction (HFpEF) (LVEF of ≥50%) and below normal LVEF; and 3) community-based controls without HF. Cluster analysis of echocardiographic parameters was performed and validated in an external cohort. Results: Among 1,765 patients with HFpEF (age 68 ± 12 years; 50% women), 1,313 (74.4%) had HFnEF. Compared with patients with HFpEF and below normal LVEF, patients with HFnEF had less coronary artery disease (33.7% vs 27.9%), greater LV wall thickness, and higher stroke volume, but similar 2-year age-adjusted all-cause mortality (HR: 0.8; 95% CI: 0.6-1.2). Five echocardiographic clusters with similar 2-year mortality were identified: 1) normal LV (normal structure despite increased filling pressure; least comorbidities) in 25%; 2) restrictive (smallest stroke volume; predominantly elderly women) in 26%; 3) hypertrophic (most concentric hypertrophy; more men) in 25%; 4) high output (greatest stroke volume; predominantly obese younger men) in 10%; and 5) atrial dominant (most left atrial myopathy; mainly elderly women with multiple comorbidities) in 10%. Similar patterns were found in the validation cohort. Conclusions: The majority of patients with HFpEF had normal LVEF, which consists of patients with different patterns of cardiac features and clinical characteristics. Results may carry implications for targeted treatment approaches in HFpEF.
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MiR-125b has therapeutic potential in the amelioration of myocardial ischemic injury. MicroRNA isomiRs, with either 5' or 3' addition or deletion of nucleotide(s), have been reported from next-generation sequencing data (NGS). However, due to technical challenges, validation and functional studies of isomiRs are few. In this study, we discovered using NGS, four 3'isomiRs of miR-125b, i.e., addition of A (adenosine), along with deletions of A, AG (guanosine) and AGU (uridine) from rat and sheep heart. These findings were validated using RT-qPCR. Comprehensive functional studies were carried out in the H9C2 hypoxia model. After miR-125b, isomiRs of Plus A, Trim A, AG and AGU mimic transfection, the H9C2 cells were subjected to hypoxic challenge. As assessed using cell viability, apoptosis, CCK-8 and LDH release, miR-125b and isomiRs were all protective against hypoxia. However, Plus A and Trim A were more effective than miR-125b, whilst Trim AG and Trim AGU had far weaker effects than miR-125b. Interestingly, both the gene regulation profile and apoptotic gene validation indicated a major overlap among miR-125b, Plus A and Trim A, whilst Trims AG and AGU revealed a different profile compared to miR-125b. Conclusions: miR-125b and its 3' isomiRs are expressed stably in the heart. miR-125b and isomiRs with addition or deletion of A might function concurrently and concordantly under specific physiological and pathophysiological conditions. In-depth understanding of isomiRs' metabolism and function will contribute to better miRNA therapeutic drug design.
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MicroRNAs , Ratos , Animais , Ovinos/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Regulação da Expressão Gênica , Apoptose/genética , Hipóxia/genéticaRESUMO
The visceral hybrid procedure combining retrograde visceral bypass grafting and completion endovascular stent grafting is a feasible alternative to conventional open surgical or wholly endovascular repairs of thoracoabdominal aneurysms (TAAA). However, the wide variability in visceral hybrid configurations means that a priori prediction of surgical outcome based on haemodynamic flow profiles such as velocity pattern and wall shear stress post repair remain challenging. We sought to appraise the clinical relevance of computational fluid dynamics (CFD) analyses in the setting of visceral hybrid TAAA repairs. Two patients, one with a type III and the other with a type V TAAA, underwent successful elective and emergency visceral hybrid repairs, respectively. Flow patterns and haemodynamic parameters were analysed using reconstructed pre- and post-operative CT scans. Both type III and type V TAAAs showed highly disturbed flow patterns with varying helicity values preoperatively within their respective aneurysms. Low time-averaged wall shear stress (TAWSS) and high endothelial cell action potential (ECAP) and relative residence time (RRT) associated with thrombogenic susceptibility was observed in the posterior aspect of both TAAAs preoperatively. Despite differing bypass configurations in the elective and emergency repairs, both treatment options appear to improve haemodynamic performance compared to preoperative study. However, we observed reduced TAWSS in the right iliac artery (portending a theoretical risk of future graft and possibly limb thrombosis), after the elective type III visceral hybrid repair, but not the emergency type V repair. We surmise that this difference may be attributed to the higher neo-bifurcation of the aortic stent graft in the type III as compared to the type V repair. Our results demonstrate that CFD can be used in complicated visceral hybrid repair to yield potentially actionable predictive insights with implications on surveillance and enhanced post-operative management, even in patients with complicated geometrical bypass configurations.
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Aneurisma da Aorta Toracoabdominal , Humanos , Tomografia Computadorizada por Raios X , Aorta , Potenciais de Ação , HemodinâmicaRESUMO
BACKGROUND AND OBJECTIVES: There is an increasing awareness of the "Heart-Brain Connection," whereby cardiovascular function is connected with cognition. Diffusion-MRI studies reported higher brain free water (FW) was associated with cerebrovascular disease (CeVD) and cognitive impairment. In this study, we investigated whether higher brain FW was related to blood cardiovascular biomarkers and whether FW mediated the associations between blood biomarkers and cognition. METHODS: Participants recruited from 2 Singapore memory clinics between 2010 and 2015 underwent collection of blood samples and neuroimaging at baseline and longitudinal neuropsychological assessments up to 5 years. We examined the associations of blood cardiovascular biomarkers (high-sensitivity cardiac troponin-T [hs-cTnT], N-terminal pro-hormone B-type natriuretic peptide [NT-proBNP], and growth/differentiation factor 15 [GDF-15]) with brain white matter (WM) and cortical gray matter (GM) FW derived from diffusion MRI using whole brain voxel-wise general linear regression. We then assessed the relationships among baseline blood biomarkers, brain FW, and cognitive decline using path models. RESULTS: A total of 308 older adults (76 with no cognitive impairment, 134 with cognitive impairment no dementia, and 98 with Alzheimer disease dementia and vascular dementia; mean [SD] age: 72.1 [8.3]) were included. We found that blood cardiovascular biomarkers were associated with higher FW in widespread WM regions and in specific GM networks including the default mode, executive control, and somatomotor networks at baseline (p < 0.01, family-wise error corrected). Baseline FW in widespread WM and network-specific GM fully mediated the associations of blood biomarkers with longitudinal cognitive decline over 5 years. Specifically, in GM, higher FW in the default mode network mediated the relationship with memory decline (hs-cTnT: ß = -0.115, SE = 0.034, p = 0.001; NT-proBNP: ß = -0.154, SE = 0.046, p = 0.001; GDF-15: ß = -0.073, SE = 0.027, p = 0.006); by contrast, higher FW in the executive control network was responsible for executive function decline (hs-cTnT: ß = -0.126, SE = 0.039, p = 0.001; NT-proBNP: ß = -0.110, SE = 0.038, p = 0.004; GDF-15: ß = -0.117, SE = 0.035, p = 0.001). Similar full mediation effects of brain FW were also identified for baseline cognition. DISCUSSION: Results suggested a role of brain FW in linking cardiovascular dysfunction to cognitive decline. These findings provide new evidence for brain-heart interactions, paving the way for prediction and monitoring of domain-specific cognitive trajectory.
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Disfunção Cognitiva , Fator 15 de Diferenciação de Crescimento , Humanos , Idoso , Biomarcadores , Imagem de Difusão por Ressonância Magnética , Água , Peptídeo Natriurético Encefálico , Fragmentos de PeptídeosRESUMO
Background: There is a need for a targeted, comprehensive, minimally invasive myocardial restoration treatment aimed at patients with chronic postinfarction heart failure that can provide a sustained effect and be conveniently adopted with transcatheter techniques. Here we evaluated the effectiveness of a platelet-rich plasma hydrogel-based, cell-free therapeutic compound delivered with the aid of a 3-dimensional electromechanical mapping and catheter-based technique (NOGA) in a porcine translational model. Methods: We assessed the feasibility of targeted, minimally invasive transcatheter NOGA-guided injections of the therapeutic compound in myocardial infarction (MI) survivors at 8 weeks post-MI. Results: Animals undergoing NOGA-guided hydrogel injections at 8 weeks post-MI demonstrated a significant improvement of the selected left ventricular parameters at a 12-week follow-up. Compared to nonintervention, the hydrogel-based therapy provided significant improvements in end-diastolic volume (-11.0% ± 11.1% vs 6.3% ± 15.2%; P = .008) and ejection fraction (-9.1% ± 16% vs 12.7% ± 18.6%; P = .009). In the slice closest to the apex, significant differences in scar area were observed; the treatment group demonstrated a smaller mean scar area in the infarcted zone compared with the control group (47.1% ± 7.0% vs 59% ± 8.2%; P = .013) and a smaller mean scar area in the border zone compared with the saline group (31.4% ± 8.3% vs 42.6% ± 9.0%; P = .016). Conclusions: The study implies a translational potential of the hydrogel-based therapy and should trigger clinical trials focused on establishing a restoration therapy that can be integrated into a clinical protocol.
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Oxidative stress (OS) is mediated by reactive oxygen species (ROS), which in cardiovascular and other disease states, damage DNA, lipids, proteins, other cellular and extra-cellular components. OS is both initiated by, and triggers inflammation, cardiomyocyte apoptosis, matrix remodeling, myocardial fibrosis, and neurohumoral activation. These have been linked to the development of heart failure (HF). Circulating biomarkers generated by OS offer potential utility in patient management and therapeutic targeting. Novel OS-related biomarkers such as NADPH oxidases (sNox2-dp, Nrf2), advanced glycation end-products (AGE), and myeloperoxidase (MPO), are signaling molecules reflecting pathobiological changes in HF. This review aims to evaluate current OS-related biomarkers and their associations with clinical outcomes and to highlight those with greatest promise in diagnosis, risk stratification and therapeutic targeting in HF.
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AIMS: In acute coronary syndrome (ACS) patients without advanced renal dysfunction [estimated glomerular filtration rate (eGFR) < 30 mL/min/1.73 m2], early (within 24 h of admission) angiotensin-converting enzyme inhibitor/angiotensin receptor blocker (ACEI/ARB) is the guideline-directed medical therapy. The clinical efficacy of early ACEI/ARB therapy among ACS patients with advanced renal dysfunction remains unclear. METHODS AND RESULTS: Among 184 850 ACS patients hospitalized from July 2014 to December 2018 in the Chinese National Electronic Disease Surveillance System Platform (CNEDSSP) cohort and 113 650 ACS patients enrolled from November 2014 to December 2019 in the Improving Care for Cardiovascular Disease in China-ACS Project (CCC-ACS) cohort, we identified 3288 and 3916 ACS patients with admission eGFR < 30 mL/min/1.73 m2 [2647 patients treated with ACEI/ARB (36.7%)], respectively. After 1:1 propensity score matching (PSM) in each cohort, Kaplan-Meier analysis showed that early ACEI/ARB use was associated with a 39% [hazard ratio (HR): 0.61, 95% confidence interval (95% CI): 0.45-0.82] and a 34% (HR: 0.66, 95% CI: 0.46-0.95) reduction in in-hospital mortality in CNEDSSP and CCC-ACS cohorts, respectively, which was consistent in multiple sensitivity analyses. A random effect meta-analysis of the two cohorts after PSM revealed a 32% reduction (risk ratio: 0.68, 95% CI: 0.55-0.84) in in-hospital mortality among ACEI/ARB users. CONCLUSIONS: Based on two nationwide cohorts in China in contemporary practice, we demonstrated that ACEI/ARB therapy initiated within 24 h of admission is associated with a reduction in in-hospital mortality in ACS patients with advanced renal dysfunction. CLINICAL TRIAL REGISTRATION: CCC-ACS project was registered at URL: https://www.clinicaltrials.gov. (Unique identifier: NCT02306616).
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Síndrome Coronariana Aguda , Nefropatias , Humanos , Sistema Renina-Angiotensina , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Síndrome Coronariana Aguda/complicações , Síndrome Coronariana Aguda/tratamento farmacológico , Antagonistas de Receptores de Angiotensina/uso terapêutico , Mortalidade Hospitalar , Registros Eletrônicos de Saúde , Nefropatias/induzido quimicamente , Nefropatias/tratamento farmacológicoRESUMO
This chapter describes an epitope-directed approach to generate antipeptide monoclonal antibodies to multiple nonoverlapping protein sites using a cocktail of fusion peptides as immunogen. It provides a step-by-step protocol on how antigenic peptides on a target protein can be identified by in silico prediction and discusses considerations for final peptide selection. Each antigenic peptide (10-20 amino acids long) is displayed as three-copy inserts on the surface exposed loop of a thioredoxin scaffold protein. The corresponding DNA coding sequence specifying the tripeptide insert flanked by Gly-Ser-Gly-Ser-Gly linkers is cloned in-frame into the Rsr II site of the thioredoxin gene in the pET-32a vector. The presence of a C-terminal polyhistidine tag (His6-tag) allows the soluble fusion proteins to be purified by one-step native immobilized metal affinity chromatography (IMAC) to greater than 95% purity. Multiple thioredoxin fusion proteins are mixed in equimolar concentrations and used as an immunogen cocktail for animal immunization. The use of short antigenic peptides of known sequence facilitates direct epitope mapping requiring only small mutagenesis scan peptide libraries in the multipin peptide format.
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Anticorpos Monoclonais , Biblioteca de Peptídeos , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/genética , Antígenos , Mapeamento de Epitopos/métodos , Epitopos , Peptídeos/genética , Tiorredoxinas/genéticaRESUMO
Background Carotid artery stiffness is associated with cognitive impairment and dementia, but the underlying mechanisms remain unknown. We examined the associations of carotid artery stiffness with cerebral small-vessel disease markers, cognition, and dementia subtypes in a memory clinic cohort. Methods and Results A total of 272 participants underwent carotid ultrasonography, 3 Tesla brain magnetic resonance imaging, and neuropsychological assessment. Carotid ultrasonography was used to assess ß-index, pressure-strain elastic modulus, and pulse-wave velocity-ß. Brain magnetic resonance images were graded for cerebral small-vessel disease markers, including white matter hyperintensities, lacunes, and cerebral microbleeds. Participants were classified as having no cognitive impairment, cognitive impairment and no dementia, or dementia subtyped as Alzheimer disease and vascular dementia. Cognition was assessed using National Institute of Neurological Disorders and Stroke-Canadian Stroke Network harmonization battery. After adjusting for age, sex, cardiovascular risk factors, and diseases, multivariable models showed that ß-index (ß=0.69; P=0.002), elastic modulus (ß=0.78; P<0.001), and pulse-wave velocity-ß (ß=0.80; P<0.001) were associated with white matter hyperintensities, and elastic modulus (odds ratio [OR], 1.39 [95% CI, 1.04-1.85]) and pulse-wave velocity-ß (OR, 1.47 [95% CI, 1.10-1.98]) were independently associated with lacunes. Similarly, ß-index (OR, 2.04 [95% CI, 1.14-4.13]), elastic modulus (OR, 2.22 [95% CI, 1.25-4.42]), and pulse-wave velocity-ß (OR, 2.50 [95% CI, 1.36-5.18]) were independently associated with vascular dementia. Carotid stiffness measures were independently associated with worse performance in global cognition, visuomotor speed, visuospatial function, and executive function. These associations became largely nonsignificant after further adjusting for cerebral small-vessel disease markers. Conclusions In memory clinic patients, carotid artery stiffness was associated with white matter hyperintensities and lacunes, impairment in global and domain-specific cognition, and causative subtypes of dementia, particularly vascular. The effects of carotid stiffness on cognition were not independent of, and were partially mediated by, cerebral small-vessel disease.
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Demência Vascular , Humanos , Demência Vascular/diagnóstico por imagem , Canadá , Artérias Carótidas/diagnóstico por imagemRESUMO
Background: Patients with cancer are at increased risk of acute myocardial infarction (AMI). It is unclear if the Atherosclerotic Cardiovascular Disease (ASCVD) risk score at incident AMI is reflective of this higher risk in patients with prior cancer than those without. Methods: We linked nationwide AMI and cancer registries from 2008 to 2019. A total of 18,200 eligible patients with ASCVD risk score calculated at incident AMI were identified (1086 prior cancer; 17,114 no cancer). Results: At incident AMI, age-standardized mean ASCVD risk was lower in the prior cancer group (18.6%) than no cancer group (20.9%) (p < 0.001). Prior to incident AMI, smoking, hypertension, hyperlipidemia and diabetes mellitus were better controlled in the prior cancer group. However post-AMI, prior cancer was associated with lower guideline-directed medical therapy usage and higher all-cause mortality (adjusted hazard ratio 1.85, 95% confidence interval 1.66−2.07). Conclusions: AMI occurred despite better control of cardiovascular risk factors and lower age-standardized estimated mean 10-year ASCVD risk among patients with prior cancer than no cancer. Prior cancer was associated with lower guideline-directed medical therapy post-AMI and higher mortality.
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Heart failure (HF) with preserved ejection fraction (HFpEF) accounts for about half of heart failure cases, but the progression of cardiac biomechanics during pathogenesis is not completely understood. We investigated a published porcine model of HFpEF, generated by progressive constriction of an aortic cuff causing progressive left ventricle (LV) pressure overload, and characterized by hypertrophy, diastolic dysfunction and overt HF with elevated plasma beta natriuretic peptide (BNP). We characterized morphological and functional features and performed image-based finite element modelling over multiple time points, so as to understand how biomechanics evolved with morphological and functional changes during pathogenesis, and to provide data for future growth and remodeling investigations. Results showed that the hypertrophic responses quickly manifested and were effective at preventing an elevation of systolic myocardial stresses, suggesting active compensated remodeling. Consequent to the hypertrophy, diastolic myocardial stresses decreased despite the elevations in diastolic pressures. The left ventricle hypertrophy (LVH) myocardium also exhibited a quick elevation of active tension at the onset of the disease. There was a progressive and significant decrease in myocardial strain, which was more significant in the longitudinal direction. Further, elevated myocardial stiffness and diastolic pressures, which reflected diastolic dysfunction, also manifested, but this was delayed from the onset of the disease. Correlation analysis showed that hypertrophy was closely correlated to systolic pressure, active tension and systolic myocardial stress, suggesting that these factors may play a role in initiating hypertrophy. Myocardial stiffness was weakly correlated to LV pressures and myocardial stresses.
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Insuficiência Cardíaca , Suínos , Animais , Volume Sistólico/fisiologia , Insuficiência Cardíaca/etiologia , Remodelação Ventricular , Função Ventricular Esquerda/fisiologia , Hipertrofia/complicaçõesRESUMO
Hydrogen sulfide (H2S) and substance P (SP) are known from animal models and in vitro studies as proinflammatory mediators. In this study, peripheral blood concentrations of H2S and SP were measured in patients with Escherichia coli or Klebsiella pneumoniae bacteraemia. Fifty patients were recruited from general wards at Christchurch Hospital, during 2020-2021. Samples from age- and sex-matched healthy subjects previously recruited as controls for studies of cardiovascular disease were used as controls. The concentrations of H2S were higher than controls on day 0, day 1, and day 2, and SP was higher than controls on all 4 days. The concentrations of H2S were highest on day 0, whereas SP concentrations were higher on day 2 than other days. Interleukin-6 and C-reactive protein were significantly higher on day 0 and day 1, respectively. The concentrations of H2S and SP did not differ between 15 non-septic (SIRS 0-1) and the 35 septic subjects (SIRS ≥ 2). Substance P concentrations were higher in subjects with abdominal infection than urinary tract infections on day 0 (p = 0.0002) and day 1 (p = 0.0091). In conclusion, the peak H2S concentrations precede the SP peak in patients with Gram-negative bacteraemia, but this response varies with the site of infection.
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Bacteriemia , Infecções por Escherichia coli , Sulfeto de Hidrogênio , Animais , Escherichia coli/metabolismo , Humanos , Sulfeto de Hidrogênio/metabolismo , Klebsiella pneumoniae/metabolismo , Substância PRESUMO
Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) inactivation is an important step toward enhanced biosafety in testing facilities and affords a reduction in the biocontainment level necessary for handling virus-positive biological specimens. Virus inactivation methods commonly employ heat, detergents, or combinations thereof. In this work, we address the dearth of information on the efficacy of SARS-CoV-2 inactivation procedures in plasma and their downstream impact on immunoassays. We evaluated the effects of heat (56 °C for 30 min), detergent (1-5% Triton X-100), and solvent-detergent (SD) combinations [0.3-1% tri-n-butyl phosphate (TNBP) and 1-2% Triton X-100] on 19 immunoassays across different assay formats. Treatments are deemed immunoassay-compatible when the average and range of percentage recovery (treated concentration relative to untreated concentration) lie between 90-110 and 80-120%, respectively. We show that SD treatment (0.3% TNBP/1% Triton-X100) is compatible with more than half of the downstream immunoassays tested and is effective in reducing SARS-CoV-2 infectivity in plasma to below detectable levels in plaque assays. This facile method offers enhanced safety for laboratory workers handling biological specimens in clinical and research settings.
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Acute myocardial infarction (AMI) is associated with heightened thrombin generation. There are limited data relating to thrombin generation and left ventricular (LV) scarring and LV dilatation in post-MI LV remodeling. We studied 113 patients with ST-segment elevation myocardial infarction (STEMI) who had undergone primary percutaneous coronary intervention (PPCI) (n = 76) or pharmaco-invasive management (thrombolysis followed by early PCI, n = 37). Endogenous thrombin potential (ETP) was measured at baseline, 1 month and 6 months. Cardiovascular magnetic resonance imaging was performed at baseline and 6 months post-MI. Outcomes studied were an increase in scar change, which was defined as an increase in left ventricular infarct size of any magnitude detected by late gadolinium enhancement, adverse LV remodeling, defined as dilatation (increase) of left ventricular end-diastolic volume (LVEDV) by more than 20% and an increase in left ventricular ejection fraction (LVEF). The mean age was 55.19 ± 8.25 years and 91.2% were men. The baseline ETP was similar in the PPCI and pharmaco-invasive groups (1400.3 nM.min vs. 1334.1 nM.min, p = 0.473). Each 10-unit increase in baseline ETP was associated with a larger scar size (adjusted OR 1.020, 95% CI 1.002-1.037, p = 0.027). Baseline ETP was not associated with adverse LV remodeling or an increase in LVEF. There was no difference in scar size or adverse LV remodeling among patients undergoing PPCI vs. pharmaco-invasive management or patients receiving ticagrelor vs. clopidogrel. Enhanced thrombin generation after STEMI is associated with a subsequent increase in myocardial scarring but not LV dilatation or an increase in LVEF at 6 months post-MI.
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Chronic heart failure (HF) is a syndrome of heterogeneous etiology associated with multiple co-morbidities. Inflammation is increasingly recognized as a key contributor to the pathophysiology of HF. Heterogeneity and lack of data on the immune mechanism(s) contributing to HF may partially underlie the failure of clinical trials targeting inflammatory mediators. We studied the Immunome in HF cohort using mass cytometry and used data-driven systems immunology approach to discover and characterize modulated immune cell subsets from peripheral blood. We showed cytotoxic and inflammatory innate lymphoid and myeloid cells were expanded in HF patients compared to healthy controls. Network analysis showed highly modular and centralized immune cell architecture in healthy control immune cell network. In contrast, the HF immune cell network showed greater inter-cellular communication and less modular structure. Furthermore, we found, as an immune mechanism specific to HF with preserved ejection fraction (HFpEF), an increase in inflammatory MAIT and CD4 T cell subsets.
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Insuficiência Cardíaca , Humanos , Imunidade Inata , Linfócitos , Volume Sistólico/fisiologia , Função Ventricular EsquerdaRESUMO
Upregulated expression of microRNA (miR)-221 is associated with downregulation of p27 and subsequent increased cell proliferation in a variety of human cancers. It is unknown whether miR-221 mimics could trigger neoplastic cellular proliferation. In vitro, we demonstrated miR-221 significantly downregulates the expression of P27 and increases proliferation of H9c2 and cardiac fibroblasts. The knockdown of PUM1 but not PUM2 abolished such effects by miR-221, as verified by RT-qPCR and western blot, direct binding of p27 3' UTR by luciferase reporter assay and cell proliferation by Ki67. In vivo expression of P27 in the rat liver, heart, kidney, spleen, and muscle were not affected by miR-221 at 1 and 4 mg/kg and concurrently full-length (FL) PUM1 (140 kDa) was not detected. Instead, isoforms of 105 and 90 kDa were observed and generated through alternative RNA slicing verified by cDNA cloning and sequencing and cathepsin K cleavage confirmed by studies with the inhibitor odanacatib. This is the first study to address the possible pro-proliferative effects of miR-221 mimic therapeutics in cardiovascular applications. Loss of FL PUM1 expression is a key factor abrogating miR-221-mediated p27 regulation, although other concurrent mechanisms cannot be excluded. Our findings provide essential insights into the context-dependent nature of miRNA functionality.
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Aims: Left ventricular ejection fraction is the conventional measure used to guide heart failure management, regardless of underlying etiology. Left ventricular global longitudinal strain (LV-GLS) by speckle tracking echocardiography (STE) is a more sensitive measure of intrinsic myocardial function. We aim to establish LV-GLS as a marker of replacement myocardial fibrosis on cardiovascular magnetic resonance (CMR) and validate the prognostic value of LV-GLS thresholds associated with fibrosis. Methods and results: LV-GLS thresholds of replacement fibrosis were established in the derivation cohort: 151 patients (57 ± 10 years; 58% males) with hypertension who underwent STE to measure LV-GLS and CMR. Prognostic value of the thresholds was validated in a separate outcome cohort: 261 patients with moderate-severe aortic stenosis (AS; 71 ± 12 years; 58% males; NYHA functional class I-II) and preserved LVEF ≥50%. Primary outcome was a composite of cardiovascular mortality, heart failure hospitalization, and myocardial infarction. In the derivation cohort, LV-GLS demonstrated good discrimination (c-statistics 0.74 [0.66-0.83]; P < 0.001) and calibration (Hosmer-Lemeshow χ2 = 6.37; P = 0.605) for replacement fibrosis. In the outcome cohort, 47 events occurred over 16 [3.3, 42.2] months. Patients with LV-GLS > -15.0% (corresponding to 95% specificity to rule-in myocardial fibrosis) had the worst outcomes compared to patients with LV-GLS < -21.0% (corresponding to 95% sensitivity to rule-out myocardial fibrosis) and those between -21.0 and -15.0% (log-rank P < 0.001). LV-GLS offered independent prognostic value over clinical variables, AS severity and echocardiographic LV mass and E/e'. Conclusion: LV-GLS thresholds associated with replacement myocardial fibrosis is a novel approach to risk-stratify patients with AS and preserved LVEF.