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2.
bioRxiv ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38854010

RESUMO

Genome sequencing efforts have led to the discovery of tens of millions of protein missense variants found in the human population with the majority of these having no annotated role and some likely contributing to trait variation and disease. Sequence-based artificial intelligence approaches have become highly accurate at predicting variants that are detrimental to the function of proteins but they do not inform on mechanisms of disruption. Here we combined sequence and structure-based methods to perform proteome-wide prediction of deleterious variants with information on their impact on protein stability, protein-protein interactions and small-molecule binding pockets. AlphaFold2 structures were used to predict approximately 100,000 small-molecule binding pockets and stability changes for over 200 million variants. To inform on protein-protein interfaces we used AlphaFold2 to predict structures for nearly 500,000 protein complexes. We illustrate the value of mechanism-aware variant effect predictions to study the relation between protein stability and abundance and the structural properties of interfaces underlying trans protein quantitative trait loci (pQTLs). We characterised the distribution of mechanistic impacts of protein variants found in patients and experimentally studied example disease linked variants in FGFR1.

3.
JAMA ; 331(21): 1824-1833, 2024 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-38734952

RESUMO

Importance: Individual cohort studies concur that the amyloidogenic V142I variant of the transthyretin (TTR) gene, present in 3% to 4% of US Black individuals, increases heart failure (HF) and mortality risk. Precisely defining carrier risk across relevant clinical outcomes and estimating population burden of disease are important given established and emerging targeted treatments. Objectives: To better define the natural history of disease in carriers across mid to late life, assess variant modifiers, and estimate cardiovascular burden to the US population. Design, Setting, and Participants: A total of 23 338 self-reported Black participants initially free from HF were included in 4 large observational studies across the US (mean [SD], 15.5 [8.2] years of follow-up). Data analysis was performed between May 2023 and February 2024. Exposure: V142I carrier status (n = 754, 3.2%). Main Outcomes and Measures: Hospitalizations for HF (including subtypes of reduced and preserved ejection fraction) and all-cause mortality. Outcomes were analyzed by generating 10-year hazard ratios for each age between 50 and 90 years. Using actuarial methods, mean survival by carrier status was estimated and applied to the 2022 US population using US Census data. Results: Among the 23 338 participants, the mean (SD) age at baseline was 62 (9) years and 76.7% were women. Ten-year carrier risk increased for HF hospitalization by age 63 years, predominantly driven by HF with reduced ejection fraction, and 10-year all-cause mortality risk increased by age 72 years. Only age (but not sex or other select variables) modified risk with the variant, with estimated reductions in longevity ranging from 1.9 years (95% CI, 0.6-3.1) at age 50 to 2.8 years (95% CI, 2.0-3.6) at age 81. Based on these data, 435 851 estimated US Black carriers between ages 50 and 95 years are projected to cumulatively lose 957 505 years of life (95% CI, 534 475-1 380 535) due to the variant. Conclusions and Relevance: Among self-reported Black individuals, male and female V142I carriers faced similar and substantial risk for HF hospitalization, predominantly with reduced ejection fraction, and death, with steep age-dependent penetrance. Delineating the individual contributions of, and complex interplay among, the V142I variant, ancestry, the social construct of race, and biological or social determinants of health to cardiovascular disease merits further investigation.


Assuntos
Insuficiência Cardíaca , Hospitalização , Pré-Albumina , Humanos , Feminino , Masculino , Idoso , Pessoa de Meia-Idade , Pré-Albumina/genética , Insuficiência Cardíaca/mortalidade , Idoso de 80 Anos ou mais , Hospitalização/estatística & dados numéricos , Negro ou Afro-Americano/genética , Estados Unidos/epidemiologia , Heterozigoto , Volume Sistólico
4.
JACC Heart Fail ; 12(6): 999-1011, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38639697

RESUMO

BACKGROUND: Although sodium glucose co-transporter 2 inhibitors (SGLT2is) improve heart failure (HF)-related symptoms and outcomes in HF with preserved ejection fraction (HFpEF), underlying mechanisms remain unclear. In HF with reduced EF, dapagliflozin altered ketone and fatty acid metabolites vs placebo; however, metabolite signatures of SGLT2is have not been well elucidated in HFpEF. OBJECTIVES: The goal of this study was to assess whether SGLT2i treatment altered systemic metabolic pathways and their relationship to outcomes in HFpEF. METHODS: Targeted profiling of 64 metabolites was performed from 293 participants in PRESERVED-HF (Dapagliflozin in PRESERVED Ejection Fraction Heart Failure), a 12-week, placebo-controlled trial of dapagliflozin. Linear regression assessed changes in metabolite factors defined by principal components analysis (PCA) with dapagliflozin vs placebo. The relationship between changes in metabolite factors with changes in study endpoints was also assessed. RESULTS: The mean age was 70 ± 11 years, 58% were female, and 29% were Black. There were no significant differences in 12 PCA-derived metabolite factors between treatment arms, including metabolites reflecting ketone, fatty acid, or branched-chain amino acid (BCAA) pathways. Combining treatment arms, changes in BCAAs and branched-chain ketoacids were negatively associated with changes in N-terminal pro-B-type natriuretic peptide; changes in medium-/long-chain acylcarnitines were positively associated with changes in N-terminal pro-B-type natriuretic peptide and negatively associated with changes in 6-minute walk test distance; and changes in ketones were negatively associated with changes in weight, without treatment interaction. CONCLUSIONS: Leveraging targeted metabolomics in a placebo-controlled SGLT2i trial of HFpEF, dapagliflozin did not alter systemic metabolic as reflected by circulating metabolites, in contrast with reported effects in HF with reduced ejection fraction. Metabolite biomarkers reflecting BCAA, ketone, and fatty acid metabolism were associated with markers of disease severity, suggesting a role for potential novel treatment targets. (Dapagliflozin in PRESERVED Ejection Fraction Heart Failure [PRESERVED-HF]; NCT03030235).


Assuntos
Compostos Benzidrílicos , Glucosídeos , Insuficiência Cardíaca , Metabolômica , Inibidores do Transportador 2 de Sódio-Glicose , Volume Sistólico , Humanos , Compostos Benzidrílicos/uso terapêutico , Glucosídeos/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/metabolismo , Feminino , Volume Sistólico/fisiologia , Idoso , Masculino , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Pessoa de Meia-Idade , Ácidos Graxos/metabolismo , Peptídeo Natriurético Encefálico/metabolismo , Peptídeo Natriurético Encefálico/sangue , Biomarcadores/metabolismo , Biomarcadores/sangue , Fragmentos de Peptídeos/sangue , Fragmentos de Peptídeos/metabolismo
6.
Polymers (Basel) ; 16(6)2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38543437

RESUMO

Noise pollution is a major threat to the health and well-being of the entire world; this issue forces researchers to find new sound absorption and insulating material. In this paper, the sound absorption coefficient and vibration damping factor of panels manufactured from Cyperus pangorei rottb and ramie fiber reinforced with epoxy resin are explored. Cyperus pangorei rottb grass fiber and ramie fiber are widely available natural fibers. Cyperus pangorei rottb grass fiber is used in mat manufacturing, whereas ramie is widely used as a fabric. Using both of these fibers, six variant panels using a vacuum resin infusion process (VRIP) were fabricated. The panels were named C, R, CR, RCR-Flat, RCR-Curved, and RCR-Perforated. All the panels were tested for the sound absorption coefficient using an impedance tube with a frequency ranging up to 6300 Hz. Modal analysis was carried out by using the impulse hammer excitation method. A micro X-ray computed tomography (CT) scan was used to study the voids present in the panels. The results were compared among the six variants. The results show that the RCR-curved panel had the highest sound-absorbing coefficient of 0.976 at a frequency range between 4500 Hz to 5000 Hz. These panels also showed better natural frequency and damping factors. The presence of internal voids in these panels enhances sound absorption properties. These panels can be used at higher frequencies.

7.
Int J Mol Sci ; 24(22)2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-38003551

RESUMO

The leptin-melanocortin pathway is pivotal in appetite and energy homeostasis. Pathogenic variants in genes involved in this pathway lead to severe early-onset monogenic obesity (MO). The MC4R gene plays a central role in leptin-melanocortin signaling, and heterozygous variants in this gene are the most common cause of MO. A targeted gene panel consisting of 52 obesity-related genes was used to screen for variants associated with obesity. Variants were analyzed and filtered to identify potential disease-causing activity and validated using Sanger sequencing. We identified two novel heterozygous variants, c.253A>G p.Ser85Gly and c.802T>C p.Tyr268His, in the MC4R gene in two unrelated patients with morbid obesity and evaluated the functional impact of these variants. The impact of the variants on the MC4R gene was assessed using in silico prediction tools and molecular dynamics simulation. To further study the pathogenicity of the identified variants, GT1-7 cells were transfected with plasmid DNA encoding either wild-type or mutant MC4R variants. The effects of allelic variations in the MC4R gene on cAMP synthesis, MC4R protein level, and activation of PKA, ERB, and CREB signaling pathways in both stimulated and unstimulated ɑ-MSH paradigms were determined for their functional implications. In silico analysis suggested that the variants destabilized the MC4R structure and affected the overall dynamics of the MC4R protein, possibly leading to intracellular receptor retention. In vitro analysis of the functional impact of these variants showed a significant reduction in cell surface receptor expression and impaired extracellular ligand binding activity, leading to reduced cAMP production. Our analysis shows that the variants do not affect total protein expression; however, they are predicted to affect the post-translational localization of the MC4R protein to the cell surface and impair downstream signaling cascades such as PKA, ERK, and CREB signaling pathways. This finding might help our patients to benefit from the novel therapeutic advances for monogenic forms of obesity.


Assuntos
Leptina , Obesidade Mórbida , Humanos , Leptina/genética , Obesidade Mórbida/genética , Catar , Alelos , alfa-MSH/farmacologia , Receptor Tipo 4 de Melanocortina/genética , Receptor Tipo 4 de Melanocortina/metabolismo , Mutação
8.
Circulation ; 148(24): 1945-1957, 2023 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-37830208

RESUMO

BACKGROUND: Apparent treatment-resistant hypertension (aTRH) is prevalent and associated with adverse outcomes in heart failure with mildly reduced or preserved ejection fraction. Less is known about the potential role of sodium-glucose co-transporter 2 inhibition in this high-risk population. In this post hoc analysis of the DELIVER trial (Dapagliflozin Evaluation to Improve the Lives of Patients with Preserved Ejection Fraction Heart Failure), we evaluated clinical profiles and treatment effects of dapagliflozin among participants with aTRH. METHODS: DELIVER participants were categorized on the basis of baseline blood pressure (BP), with aTRH defined as BP ≥140/90 mm Hg (≥130/80 mm Hg if diabetes) despite treatment with 3 antihypertensive drugs including a diuretic. Nonresistant hypertension was defined as BP above threshold but not meeting aTRH criteria. Controlled BP was defined as BP under threshold. Incidence of the primary outcome (cardiovascular death or worsening heart failure event), key secondary outcomes, and safety events was assessed by baseline BP category. RESULTS: Among 6263 DELIVER participants, 3766 (60.1%) had controlled BP, 1779 (28.4%) had nonresistant hypertension, and 718 (11.5%) had aTRH at baseline. Participants with aTRH had more cardiometabolic comorbidities and tended to have higher left ventricular ejection fraction and worse kidney function. Rates of the primary outcome were 8.7 per 100 patient-years in those with controlled BP, 8.5 per 100 patient-years in the nonresistant hypertension group, and 9.5 per 100 patient-years in the aTRH group. Relative treatment benefits of dapagliflozin versus placebo on the primary outcome were consistent across BP categories (Pinteraction=0.114). Participants with aTRH exhibited the greatest absolute reduction in the rate of primary events with dapagliflozin (4.1 per 100 patient-years) compared with nonresistant hypertension (2.7 per 100 patient-years) and controlled BP (0.8 per 100 patient-years). Irrespective of assigned treatment, participants with aTRH experienced a higher rate of reported vascular events, including myocardial infarction and stroke, over study follow-up. Dapagliflozin modestly reduced systolic BP (by ≈1 to 3 mm Hg) without increasing risk of hypotension, hypovolemia, or other serious adverse events, irrespective of BP category, but did not improve the proportion of participants with aTRH attaining goal BP over time. CONCLUSIONS: aTRH was identified in >1 in 10 patients with heart failure and left ventricular ejection fraction >40% in DELIVER. Dapagliflozin consistently improved clinical outcomes and was well-tolerated, including among those with aTRH. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03619213.


Assuntos
Insuficiência Cardíaca , Hipertensão , Humanos , Volume Sistólico , Função Ventricular Esquerda , Compostos Benzidrílicos/efeitos adversos
9.
JAMA Cardiol ; 8(8): 784-788, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37212191

RESUMO

Importance: Hereditary transthyretin cardiac amyloidosis is an increasingly recognized cause of heart failure (HF) with distinct treatment. The amyloidogenic pV142I (V122I) variant is present in 3% to 4% of Black individuals in the US and increases the risk for atrial fibrillation (AF), HF, and mortality. Since hereditary transthyretin cardiac amyloidosis demonstrates age-dependent anatomic penetrance, evaluation later in life may identify survivors at particularly high risk. Objective: To estimate age-dependent risks for cardiovascular events with the variant. Design, Settings, and Participants: This cohort study analyzed Black participants from the Atherosclerosis Risk in Communities (ARIC) study attending visit 1 (1987-1989) (followed up until 2019; median follow-up, 27.6 years). Data analyses were completed from June 2022 to April 2023. Exposure: pV142I carrier status. Main outcomes: The association between the variant and AF, HF hospitalization, mortality, and a composite of HF hospitalization or mortality was modeled by generating 10-year absolute risk differences for each year between ages 53 (the median age at visit 1) and 80 years, adjusting for the first 5 principal components of ancestry and sex. As an example, 5- and 10-year risk differences were specifically estimated for the composite outcome among participants surviving to age 80 years. Results: Among 3856 Black participants (including 124 carriers) at visit 1, 2403 (62%) were women, 2140 (56%) had hypertension, and 740 (20%) had diabetes, with no differences between groups. The 10-year absolute risk difference between ages 53 and 80 years increased over time for each outcome. Statistical significance for increased 10-year risk difference emerged near ages 65 years for AF, 70 years for HF hospitalization, and 75 years for mortality. Among participants surviving to age 80 years, carriers had a 20% (95% CI, 2%-37%) and 24% (95% CI, 1%-47%) absolute increased risk for HF hospitalization or death at 5 and 10 years, respectively. Thus, at age 80 years, only 4 carriers would need to be identified to attribute 1 HF hospitalization or death over the following decade to the variant. Conclusions and Relevance: In this study, age-specific risks were provided for relevant outcomes with the pV142I variant. Despite a relatively benign course during earlier years, Black individuals who carry the pV142I variant surviving into later life may be particularly vulnerable. These data may inform timing for screening, risk counseling to patients, and potential strategies for early targeted therapy.


Assuntos
Neuropatias Amiloides Familiares , Fibrilação Atrial , Insuficiência Cardíaca , Pré-Albumina , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Neuropatias Amiloides Familiares/complicações , Neuropatias Amiloides Familiares/genética , Fibrilação Atrial/complicações , Negro ou Afro-Americano , Estudos de Coortes , Pré-Albumina/genética , Pessoa de Meia-Idade , Idoso
12.
JACC Heart Fail ; 11(1): 76-89, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36599553

RESUMO

BACKGROUND: Optimizing systolic blood pressure (SBP) in heart failure (HF) with preserved ejection fraction carries a Class I recommendation but with limited evidence. Sodium-glucose cotransporter 2 (SGLT2) inhibitors have antihypertensive effects across cardiovascular disease. OBJECTIVES: The authors examined the interplay between SBP and treatment effects of dapagliflozin on SBP and cardiovascular outcomes. METHODS: The authors analyzed 6,263 DELIVER (Dapagliflozin Evaluation to Improve the LIVEs of Patients With PReserved Ejection Fraction Heart Failure) participants and related baseline and mean achieved SBP categories (<120, 120-129, 130-139, ≥140 mm Hg) to the primary outcome (cardiovascular death or worsening HF), secondary outcomes, and safety events. They analyzed whether the blood pressure-lowering effects of dapagliflozin accounted for its treatment effects by adjusting for the change in SBP from baseline to 1 month. RESULTS: The average age was 72 ± 10 years and 44% were women. SBP <120 mm Hg was associated with higher HF and mortality events, although amputation and stroke risk increased with higher SBP. Dapagliflozin reduced SBP by 1.8 (95% CI: 1.1-2.5) mm Hg compared with placebo at 1 month. The treatment effect of dapagliflozin on the primary outcome and Kansas City Cardiomyopathy Questionnaire total symptom score was consistent across SBP (interaction P = 0.15 and P = 0.98, respectively). Adverse events between arms were similar across SBP categories. The treatment effect was not accounted for by reducing blood pressure. CONCLUSIONS: In DELIVER, risk by SBP was augmented in the lowest and highest categories and varied by endpoint examined. Dapagliflozin modestly decreased SBP compared with placebo. Dapagliflozin was similarly efficacious and safe across the range of baseline SBP. The beneficial effects of dapagliflozin were not accounted for the changes in SBP. (Dapagliflozin Evaluation to Improve the LIVEs of Patients With PReserved Ejection Fraction Heart Failure [DELIVER]; NCT03619213).


Assuntos
Insuficiência Cardíaca , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Masculino , Pressão Sanguínea/fisiologia , Volume Sistólico/fisiologia , Compostos Benzidrílicos/uso terapêutico , Compostos Benzidrílicos/farmacologia
14.
Circ Heart Fail ; 16(2): e010069, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36458538

RESUMO

BACKGROUND: Heuristic biases are increasingly recognized, and potentially modifiable, contributors to patient care and outcomes. Left digit bias is a cognitive bias where continuous variables are categorized by their left-most digit. The impact of this heuristic bias applied to patient age on quality of care in heart failure has not been explored. METHODS: We examined participants admitted from 2005 to 2021 in the Get With The Guidelines-Heart Failure registry. To create 2 naturally randomized groups, isolating the effect of left digit bias, we dichotomized patients into those discharged within 60 days prior to their 80th birthday (N=4238) and those discharged within 60 days after their 80th birthday (N=4329). We performed multivariable logistic regression to assess the association between discharge date relative to 80th birthday and several in-hospital quality metrics and in-hospital outcomes. Among Medicare participants (N=2759), we performed adjusted Cox regression to analyze the relationship between discharge date and risk of 1-year mortality or readmission. RESULTS: Among 8567 patients, 50.4% were female, 73% were non-Hispanic White, and 42.9% had an ejection fraction ≤40%. Discharge date relative to 80th birthday was not associated with numerous in-hospital quality metrics or in-hospital outcomes on unadjusted or adjusted logistic regression. Among Medicare beneficiaries, there was no association between discharge date and risk of mortality or readmission at 1-year postdischarge (hazard ratio, 1.03 [95% CI, 0.95-1.12]; P=0.52). CONCLUSIONS: In a large registry of patients hospitalized for heart failure, we did not detect a left digit bias' with respect to age at discharge, which resulted in differential quality of care or outcomes.


Assuntos
Insuficiência Cardíaca , Humanos , Feminino , Idoso , Estados Unidos , Masculino , Insuficiência Cardíaca/diagnóstico , Readmissão do Paciente , Assistência ao Convalescente , Heurística , Alta do Paciente , Medicare , Hospitalização
15.
JACC Cardiovasc Imaging ; 15(11): 1944-1955, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36357136

RESUMO

BACKGROUND: Patients with suspected cardiac sarcoidosis frequently undergo fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) imaging to assess disease activity at baseline and after treatment initiation. OBJECTIVES: This study investigated the effect of immunosuppressive therapy and biopsy status to achieve complete treatment response (CTR), partial treatment response (PTR), or no response (NR) on myocardial FDG-PET/CT. METHODS: This study analyzed 83 patients with suspected cardiac sarcoidosis (aged 53 ± 1.8 years, 71% were male, 69% were White, 61% had a history of biopsy-confirmed sarcoidosis) who were treatment naive, had evidence of myocardial FDG at baseline, and underwent repeat PET imaging after treatment initiation. CTR was graded visually, and PTR/NR were measured both visually and quantitatively using the total glycolytic activity. Patients were also evaluated for the occurrence of death, sustained ventricular arrhythmias, and heart failure admissions. RESULTS: Overall, 59 patients (71%) achieved CTR/PTR (30%/41%) at follow-up scan (P = 0.04). Total glycolytic activity and visual estimate of PTR/NR had excellent agreement (κ = 0.86 [95% CI: 0.72-0.99]; P < 0.0001). In patients receiving prednisone only, the highest rates of CTR/PTR were observed in patients initiated on moderate or high dose (P < 0.01). In a regression model, moderate prednisone start dose (P = 0.03) was more strongly associated with achieving CTR/PTR than was high prednisone start dose. However, the latter patients were tapered faster between start dose and follow-up scan (P < 0.01). After a median follow-up of 4.7 (IQR: 3.1-7.8) years, patients who were biopsy-proven (vs non-biopsy-proven; P = 0.029) and with preserved left ventricular function (P = 002) were less likely to experience major adverse cardiac events. Outcomes based on treatment response status (CTR vs PTR vs NR; P = 0.23) were not significantly different. CONCLUSIONS: Among patients with suspected sarcoidosis and evidence of myocardial inflammation, treatment response by serial FDG-PET was variable, but a favorable response was more common when using moderate-to-high intensity prednisone dose. Biopsy-proven individuals and those with preserved systolic function were less likely to experience adverse outcomes during follow-up.


Assuntos
Cardiomiopatias , Miocardite , Sarcoidose , Humanos , Masculino , Feminino , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Compostos Radiofarmacêuticos , Prednisona , Cardiomiopatias/diagnóstico por imagem , Cardiomiopatias/tratamento farmacológico , Cardiomiopatias/patologia , Valor Preditivo dos Testes , Sarcoidose/diagnóstico por imagem , Sarcoidose/tratamento farmacológico , Sarcoidose/patologia , Tomografia por Emissão de Pósitrons/métodos , Terapia de Imunossupressão
16.
Materials (Basel) ; 15(20)2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36295434

RESUMO

This work analyzes a novel solid-state manufacturing approach of a friction stir additive manufacturing (FSAM) technique for fabricating multiple layers of alternating gradient composite structure using alternate layers of AA6061-T6 and AA7075-T6 aluminum alloys of 3 mm thickness. The evolution of the microstructure along the build direction and its impact on the tensile and microhardness properties were examined using optical microscopy, tensile tests, and Vickers microhardness tests. Nonuniform microstructures were detected along the build direction, and it was concluded that the most productive part of the construction was the nugget zone, which had fine equiaxed grains. It was identified that the grain sizes and precipitate sizes were affected by the varying thermal cycles created by the multiple passes of the tool. These events were identified as the primary reasons for the increase in strength and hardness of the FSAM build from the lower layer to the upper layer. In the final FSAM build the maximum hardness value was obtained as 182.3 HV and the ultimate tensile strength (UTS) was 420 MPa both of which were identified at the topmost layer. Moreover, the postmortem of the fractured samples revealed that the cause of failure was a combination of both ductile and brittle fractures. The findings of this study suggest that the FSAM approach may be used to fabricate large structures that are free of defects having expected mechanical characteristics and hence the newly fabricated composite can be used as a suitable substitute for the conventional AA6061 material applied in automobile components for its improved performance.

17.
Circulation ; 146(11): 808-818, 2022 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-35603596

RESUMO

BACKGROUND: Sodium-glucose cotransporter-2 inhibitors are foundational therapy in patients with heart failure with reduced ejection fraction (HFrEF), but underlying mechanisms of benefit are not well defined. We sought to investigate the relationships between sodium-glucose cotransporter-2 inhibitor treatment, changes in metabolic pathways, and outcomes using targeted metabolomics. METHODS: DEFINE-HF (Dapagliflozin Effects on Biomarkers, Symptoms and Functional Status in Patients With HF With Reduced Ejection Fraction) was a placebo-controlled trial of dapagliflozin in HFrEF. We performed targeted mass spectrometry profiling of 63 metabolites (45 acylcarnitines [markers of fatty acid oxidation], 15 amino acids, and 3 conventional metabolites) in plasma samples at randomization and 12 weeks. Using mixed models, we identified principal components analysis-defined metabolite clusters that changed differentially with treatment and examined the relationship between change in metabolite clusters and change in Kansas City Cardiomyopathy Questionnaire scores and NT-proBNP (N-terminal probrain natriuretic peptide). Models were adjusted for relevant clinical covariates and nominal P<0.05 with false discovery rate-adjusted P<0.10 was used to determine statistical significance. RESULTS: Among the 234 DEFINE-HF participants with targeted metabolomic data, the mean age was 62.0±11.1 years, 25% were women, 38% were Black, and mean ejection fraction was 27±8%. Dapagliflozin increased ketone-related and short-chain acylcarnitine as well as medium-chain acylcarnitine principal components analysis-defined metabolite clusters compared with placebo (nominal P=0.01, false discovery rate-adjusted P=0.08 for both clusters). However, ketosis (ß-hydroxybutyrate levels >500 µmol/L) was achieved infrequently (3 [2.5%] in dapagliflozin arm versus 1 [0.9%] in placebo arm) and supraphysiologic levels were not observed. Increases in long-chain acylcarnitine, long-chain dicarboxylacylcarnitine, and aromatic amino acid metabolite clusters were associated with decreases in Kansas City Cardiomyopathy Questionnaire scores (ie, worse quality of life) and increases in NT-proBNP levels, without interaction by treatment group. CONCLUSIONS: In this study of targeted metabolomics in a placebo-controlled trial of sodium-glucose cotransporter-2 inhibitors in HFrEF, we observed effects of dapagliflozin on key metabolic pathways, supporting a role for altered ketone and fatty acid biology with sodium-glucose cotransporter-2 inhibitors in patients with HFrEF. Only physiologic levels of ketosis were observed. In addition, we identified several metabolic biomarkers associated with adverse HFrEF outcomes. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT02653482.


Assuntos
Cardiomiopatias , Insuficiência Cardíaca , Cetose , Inibidores do Transportador 2 de Sódio-Glicose , Disfunção Ventricular Esquerda , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Benzidrílicos/efeitos adversos , Biomarcadores , Cardiomiopatias/complicações , Ácidos Graxos , Glucosídeos , Cetonas/uso terapêutico , Qualidade de Vida , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Volume Sistólico/fisiologia , Disfunção Ventricular Esquerda/complicações
18.
J Am Coll Cardiol ; 79(16): 1549-1561, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35450571

RESUMO

BACKGROUND: Limited data exist to characterize novel measures of left atrial (LA) structure and function in older adults without prevalent heart failure (HF). OBJECTIVES: The aim was to assess reference range of LA measures, their associations with N-terminal pro-B-type natriuretic-peptide (NT-proBNP) and the related risk for incident HF or death. METHODS: We analyzed LA structure (LA maximal [LAViMax] and minimal volume indexed by body surface area) and function (LA emptying fraction, LA reservoir, conduit, and contraction strain) in 4,901 participants from the ARIC (Atherosclerosis Risk In Communities) study (mean age 75 ± 5 years, 40% male, and 19% Black) without prevalent HF. We assessed sex-specific 10th and 90th percentile ARIC-based reference limits in 301 participants free of prevalent cardiovascular disease, and related LA measures to NT-proBNP and incident HF or death (median follow-up of 5.5 years) in the whole ARIC cohort. RESULTS: Approximately 20% of the overall population had LA abnormalities according to the ARIC-based reference limit. Each LA measure was associated with NT-proBNP and, except for LAViMax, with incident HF or death after multivariable adjustment (including left ventricular function and NT-proBNP). Results were consistent in participants with normal LAViMax (P for interaction > 0.05). LA measures were prognostic for both incident HF with preserved ejection fraction or death and incident HF with reduced ejection fraction or death. When added to HF risk factors and NT-proBNP (baseline C-statistics = 0.74) all LA measures, except for LAViMax, significantly enhanced the prognostic accuracy. CONCLUSIONS: Novel measures of LA structure and function, but not standard assessment by LAViMax, are associated with increased risk of incident HF or death regardless of measures of left ventricular function and NT-proBNP.


Assuntos
Cardiopatias , Insuficiência Cardíaca , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Feminino , Átrios do Coração/diagnóstico por imagem , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/epidemiologia , Humanos , Masculino , Peptídeo Natriurético Encefálico , Fragmentos de Peptídeos , Volume Sistólico , Função Ventricular Esquerda
19.
Eur Heart J Cardiovasc Imaging ; 23(12): 1690-1697, 2022 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-35366303

RESUMO

AIMS: The ketogenic diet (KD) is standard-of-care to achieve myocardial glucose suppression (MGS) for assessing inflammation using fluorine-18 fluorodeoxyglucose-positron emission tomography (FDG-PET). As KD protocols remain highly variable between centres (including estimation of nutrient intake by dietary logs for adequacy of dietary preparation), we aimed to assess the predictive utility of nutrient intake in achieving MGS. METHODS AND RESULTS: Nineteen healthy participants underwent short-term KD, with FDG-PET performed after 1 and 3 days of KD (goal carbohydrate intake <20 g/day). Nutrient consumption was estimated from dietary logs using nutrition research software. The area under receiver operating characteristics (AUROC) of macronutrients (carbohydrate, fat, and protein intake) for predicting MGS was analysed. The association between 133 nutrients and 4 biomarkers [beta-hydroxybutyrate (BHB), non-esterified fatty acids, insulin, and glucagon] with myocardial glucose uptake was assessed using mixed effects regression with false discovery rate (FDR) correction. Median (25th-75th percentile) age was 29 (25-34) years, 47% were women, and 42% were non-white. Median (25th-75th percentile) carbohydrate intake (g) was 18.7 (13.1-30.7), 16.9 (10.4-28.7), and 21.1 (16.6-29.0) on Days 1-3. No macronutrient intake (carbohydrate, fat, or protein) predicted MGS (c-statistic 0.45, 0.53, 0.47, respectively). Of 133 nutrients and 4 biomarkers, only BHB was associated with myocardial glucose uptake after FDR correction (corrected P-value 0.003). CONCLUSIONS: During highly supervised, short-term KD, approximately half of patients meet strict carbohydrate goals. Yet, in healthy volunteers, dietary review does not provide reassurance for adequacy of myocardial preparation since no clear thresholds for carbohydrate or fat intake reliably predict MGS.


Assuntos
Dieta Cetogênica , Fluordesoxiglucose F18 , Humanos , Feminino , Adulto , Masculino , Tomografia por Emissão de Pósitrons/métodos , Nutrientes , Glucose , Compostos Radiofarmacêuticos
20.
J Am Heart Assoc ; 11(7): e024999, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-35377160

RESUMO

Background Patients with heart failure (HF) are at high risk for atherosclerotic cardiovascular disease. Studies of atherothrombotic treatments in this population have been disappointing to date. Icosapent ethyl reduced the risk of atherosclerotic cardiovascular disease among a broad array of statin-treated patients at elevated risk for atherosclerotic cardiovascular disease. Whether the treatment benefits of icosapent ethyl are consistent among those with HF is unknown. Methods and Results REDUCE-IT (Reduction of Cardiovascular Events With Icosapent Ethyl-Intervention Trial) randomized 8179 participants, including 1446 (17.7%) patients with a history of HF (icosapent ethyl, N=703; and placebo, N=743). The primary end point was a composite of cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, coronary revascularization, or unstable angina. We used Cox regression to estimate the risk of outcomes of participants with and without HF. We estimated the placebo-controlled change in triglycerides and hs-CRP (high-sensitivity C-reactive protein) from baseline to 2 years. Among 1446 patients with HF, median age was 63.0 years, median body mass index was 31.0 kg/m2, and more were men (69.3%). Icosapent ethyl reduced triglycerides (median reduction, 33.5 mg/dL, or 15.4%; P<0.0001) and hs-CRP (35.1%; P<0.0001) compared with placebo, similar to patients without HF (P-interaction>0.90). The treatment effect on the primary end point in patients with HF history (hazard ratio [HR], 0.87; 95% CI, 0.70-1.08) was consistent with the effects observed in patients without HF history (HR, 0.73; 95% CI, 0.65-0.81) (P-interaction=0.13). Conclusions In REDUCE-IT, icosapent ethyl provided similar improvements in triglyceride levels and hs-CRP as well as similar cardiovascular risk reduction in patients with and without HF. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT01492361.


Assuntos
Doenças Cardiovasculares , Insuficiência Cardíaca , Doenças Cardiovasculares/induzido quimicamente , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Ácido Eicosapentaenoico/efeitos adversos , Ácido Eicosapentaenoico/análogos & derivados , Fatores de Risco de Doenças Cardíacas , Insuficiência Cardíaca/induzido quimicamente , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
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