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1.
RSC Adv ; 14(15): 10390-10396, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38567334

RESUMO

Proton exchange membrane water electrolysis (PEMWE) is a promising technology for green hydrogen production. However, its large-scale commercial application is limited by its high precious metal loading, because low catalyst loading leads to reduced electron transport channels and decreased water transportation, etc. Herein, we study the electrode level strategy for reducing Ir loading by the optimization of the micro-structure of the anode catalyst layer via SnO2 doping. The pore structure and electron conductive network of the anode catalyst layer can be simultaneously improved by SnO2 doping, under appropriate conditions. Therefore, mass transfer polarization and ohmic polarization of the single cell are reduced. Moreover, the enhanced pore structure and improved electron conduction network collectively contribute to a decreased occurrence of charge transfer polarization. By this strategy, the performance of the single cell with the Ir loading of 1.5 mg cm-2 approaches the single cell with the higher Ir loading of 2.0 mg cm-2, which means that SnO2 doping saves about 25% loading of Ir. This paper provides a perspective at the electrode level to reduce the precious metal loading of the anode in PEMWE.

2.
JAMA Netw Open ; 7(2): e240219, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38386318

RESUMO

Importance: Prior findings from the Look AHEAD trial showed no significant reduction in the risk of cardiovascular events by lifestyle-induced weight loss among individuals with type 2 diabetes (T2D) and overweight or obesity. However, physical activity (PA) may modify the changes in cardiovascular risk associated with weight loss. Objective: To examine the joint association of weight loss and PA with the risk of adverse cardiovascular events in patients with T2D and overweight or obesity. Design, Setting, and Participants: This cohort study was a post hoc analysis of the Look AHEAD randomized clinical trial, which compared the cardiovascular effects of weight loss by intensive lifestyle intervention vs diabetes support and education among individuals with T2D and overweight or obesity. The study was conducted from June 2001 to September 2012, and participants were patients in the substudy of accelerometry-measured PA from 8 locations in the United States. Data were analyzed from June to August 2023. Exposures: Body weight change and accelerometer-derived PA volume across the first 4 years. Main Outcomes and Measures: The primary outcome was a composite cardiovascular outcome including cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for angina. Results: Among a total of 1229 participants (mean [SD] age, 60 [7] years; 533 male [43%]), 333 (27%) achieved and maintained weight loss for the first 4 years. Among the individuals who maintained weight loss, 105 (32%) maintained high PA volume. During a median of 9.5 years of follow-up, 198 participants (16.1%) experienced the primary outcome. Compared with those with low PA volume and no weight loss (105 [15.8%]), maintaining high PA volume and weight loss was associated with a 61% lower risk of the primary end point (hazard ratio, 0.39; 95% CI, 0.19-0.81; P = .01). However, there was no significant difference in the risk of the primary end point among those with either weight loss only or high PA only. The multiplicative interaction between weight loss and PA for the risk of cardiovascular events was also significant (P for interaction = .01). Conclusions and Relevance: In this cohort study, maintaining weight loss and higher PA volume was associated with a lower risk of the composite cardiovascular outcome. The findings suggest that the cardiovascular benefits of PA may vary and be enhanced by weight loss among individuals with T2D and overweight or obesity.


Assuntos
Diabetes Mellitus Tipo 2 , Sobrepeso , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Angina Pectoris , Estudos de Coortes , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/terapia , Exercício Físico , Obesidade/complicações , Obesidade/epidemiologia , Obesidade/terapia , Sobrepeso/complicações , Sobrepeso/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto , Feminino , Idoso
3.
Chempluschem ; : e202300782, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38345544

RESUMO

Photopolymerizations have garnered significant attention in polymer science due to their low polymerization temperature, high production efficiency, environmental friendliness, and spatial controllability. Despite these merits, the poor penetration and severe chemical damage from ultraviolet/visible (UV/Vis) light resources pose significant barriers to their success in conventional photopolymerizations. A recent breakthrough involving the utilization of near-infrared (NIR) laser with long wavelength has been exploited for diverse applications. With the combination of a NIR photosensitizer (PS), NIR-induced photopolymerizations have been successfully developed to alleviate the challenges in conventional methods. The enhancement of penetration depth and safety of NIR-induced photopolymerizations can contribute significantly to improving the efficiency of polymerization for production of intricate structures across various scales. In this concept, the typical types of PSs and polymerization mechanisms (PMs) within the NIR-induced photopolymerization systems have been classified in detail. Additionally, the applications of various polymers achieved by NIR-induced photopolymerizations are summarized. Furthermore, research directions and future challenges of this field are also discussed comprehensively.

4.
Atherosclerosis ; 391: 117431, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38408412

RESUMO

BACKGROUND AND AIMS: The gut microbe-derived metabolite trimethylamine-N-oxide (TMAO) has been implicated in the development of cardiovascular fibrosis. Endoplasmic reticulum (ER) stress occurs after the dysfunction of ER and its structure. The three signals PERK/ATF-4, IRE-1α/XBP-1s and ATF6 are activated upon ER stress. Recent reports have suggested that the activation of PERK/ATF-4 and IRE-1α/XBP-1s signaling contributes to cardiovascular fibrosis. However, whether TMAO mediates aortic valve fibrosis by activating PERK/ATF-4 and IRE-1α/XBP-1s signaling remains unclear. METHODS: Human aortic valve interstitial cells (AVICs) were isolated from aortic valve leaflets. PERK IRE-1α, ATF-4, XBP-1s and CHOP expression, and production of collagen Ⅰ and TGF-ß1 were analyzed following treatment with TMAO. The role of PERK/ATF-4 and IRE-1α/XBP-1s signaling pathways in TMAO-induced fibrotic formation was determined using inhibitors and small interfering RNA. RESULTS: Diseased valves produced greater levels of ATF-4, XBP-1, collagen Ⅰ and TGF-ß1. Interestingly, diseased cells exhibited augmented PERK/ATF-4 and IRE-1α/XBP-1s activation after TMAO stimulation. Inhibition and silencing of PERK/ATF-4 and IRE-1α/XBP-1s each resulted in enhanced suppression of TMAO-induced fibrogenic activity in diseased cells. Mice treated with dietary choline supplementation had substantially increased TMAO levels and aortic valve fibrosis, which were reduced by 3,3-dimethyl-1-butanol (DMB, an inhibitor of trimethylamine formation) treatment. Moreover, a high-choline and high-fat diet remodeled the gut microbiota in mice. CONCLUSIONS: TMAO promoted aortic valve fibrosis through activation of PERK/ATF-4 and IRE-1α/XBP-1s signaling pathways in vitro and in vivo. Modulation of diet, gut microbiota, TMAO, PERK/ATF-4 and IRE1-α/XBP-1s may be a promising approach to prevent aortic valve fibrosis.


Assuntos
Microbioma Gastrointestinal , Fator de Crescimento Transformador beta1 , Camundongos , Humanos , Animais , Fator de Crescimento Transformador beta1/metabolismo , Valva Aórtica/metabolismo , Metilaminas/toxicidade , Metilaminas/metabolismo , Fibrose , Colágeno , Colina , Óxidos
5.
Eur J Prev Cardiol ; 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38394450

RESUMO

AIMS: Both coronary artery calcification (CAC) and aortic valve calcification (AVC) are strongly associated with cardiovascular diseases (CVD), but data about the prognostic significance of multiple cardiovascular calcifications are limited. We aim to investigate the interaction relationship of AVC and CAC for major events. METHODS: We included 6,695 participants from the Multi-Ethnic Study of Atherosclerosis at baseline, and divided them into four groups: 1) no AVC or CAC; 2) only AVC; 3) only CAC; 4) with CAC and CAC. Cox regression model and Kaplan-Meier method were used to analyze CVD outcomes. We evaluated the interaction between AVC and CAC, and their added predictive value based on the pooled cohort equations (PCEs). The subgroup analyses were also explored. RESULTS: Among 6,695 participants (mean age 62.2 ± 10.2 years, 47.2% male), after follow-up, 943 cases (14.1%) of CVD and 1274 cases (19.0%) of all-cause death occurred. For participants with both AVC and CAC, the risk of CVD significantly increased {HR =3.43 (2.69-4.37), P <0.001}, even higher than the sum of the ones with only AVC and only CAC. This trend remained the same for all-cause death and among subgroup analysis. The addictive interaction was statistically significant (P <0.001). When added AVC and CAC, the predictive value of PCEs increased. CONCLUSIONS: Our results indicated a synergistical interaction between valve calcification and coronary calcification to cardiovascular diseases. Management for both AVC and CAC may bring health co-benefits in preventing poor outcomes.


We investigated the interaction relationship between AVC and CAC in 6,695 participants with measurements for cardiovascular calcifications at baseline in MESA study, and the prognostic significance of AVC in relation to CAC. Our study found that CAC and AVC worked independently and synergistically to predict the risk of cardiovascular diseases and all-cause death. Our results have shown that patients suffering from both CAC and AVC are more likely to develop a poor prognosis, therefore it's necessary to implement earlier and more positive intervention for CVD prevention in this certain subpopulation.

6.
Nano Lett ; 24(7): 2308-2314, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38324009

RESUMO

Two-dimensional (2D) nonlayered transition metal dichalcogenide (TMD) materials are emergent platforms for various applications from catalysis to quantum devices. However, their limited availability and nonstraightforward synthesis methods hinder our understanding of these materials. Here, we present a novel technique for synthesizing 2D nonlayered AuCrS2 via Au-assisted chemical vapor deposition (CVD). Our detailed structural analysis reveals the layer-by-layer growth of [AuCrS2] units atop an initial CrS2 monolayer, with Au binding to the adjacent monolayer of CrS2, which is in stark contrast with the well-known metal intercalation mechanism in the synthesis of many other 2D nonlayered materials. Theoretical calculations further back the crucial role of Cr in increasing the mobility of Au species and strengthening the adsorption energy of Au on CrS2, thereby aiding the growth throughout the CVD process. Additionally, the resulting free-standing nanoporous AuCrS2 (NP-AuCrS2) exhibits exceptional electrocatalytic properties for the hydrogen evolution reaction.

7.
Glob Heart ; 19(1): 3, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38222098

RESUMO

Background: Few studies have examined the relationship between the fluctuation of heart rate control over time and cardiovascular outcomes in patients with atrial fibrillation. Our study sought to evaluate the independent association between time in target range (TIR) of resting heart rate and cardiovascular outcomes in the AFFIRM (Atrial Fibrillation Follow-Up Investigation of Rhythm Management) study. Methods: Target range of resting heart was defined as less than 80 beats per minute (bpm) for both rate and rhythm control groups. Time in target range was estimated over the first 8 months of follow-up using Rosendaal interpolation method. The association between TIR of resting heart rate and cardiovascular outcomes was estimated using adjusted Cox proportional hazards regression models. Results: Time in target range of resting heart rate (months 0 through 8) was 71 ± 34% in the rate control group and 83 ± 27% in the rhythm control group. Each 1-SD increase in TIR of resting heart rate was significantly associated with lower risk of major adverse cardiovascular events after full adjustment for demographics, medical history and history of prior heart surgery, as well as all-cause mortality. Conclusions: Time in target range of resting heart rate independently predicts the risk of cardiovascular outcomes in patients with atrial fibrillation. Long-term maintenance of heart rate on target is of great importance for patients with atrial fibrillation.


Assuntos
Fibrilação Atrial , Humanos , Frequência Cardíaca/fisiologia
8.
J Am Heart Assoc ; 13(3): e030132, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38293950

RESUMO

BACKGROUND: An association between variability of cardiovascular risk factors and cardiovascular events has been reported. We examined whether intensive lifestyle intervention (ILI) for weight loss decreased variability of cardiovascular risk factors with a view to additional cardiometabolic benefits. METHODS AND RESULTS: This study was a post hoc secondary analysis of the Look AHEAD (Action for Health in Diabetes) study. Cardiovascular risk factors were measured at 1-year intervals for 4 years in 4249 adults with overweight or obesity and type 2 diabetes who were randomly assigned to ILI or diabetes support and education. Long-term variability was defined as the SD of cardiovascular risk factors during 4-year follow-up. At multiple linear regression analysis, compared with the diabetes support and education group, the ILI group was associated with reduced variability of fasting blood glucose (ß=-1.49 [95% CI, -2.39 to -0.59]), total cholesterol (ß=-1.12 [95% CI, -1.75 to -0.48]), and low-density lipoprotein cholesterol (ß=-1.04 [95% CI, -1.59 to -0.49]), as well as increased variability of systolic blood pressure (ß=0.27 [95% CI, 0.00-0.54]). No significant effect of ILI was found on the variability of diastolic blood pressure (ß=-0.08 [95% CI, -0.22 to 0.05]). CONCLUSIONS: Among adults with overweight or obesity and type 2 diabetes, ILI may reduce long-term variability of fasting blood glucose, total cholesterol, and low-density lipoprotein cholesterol. Our results support that ILI should be recommended to individuals with diabetes as part of management of long-term glycemic and blood lipid control.


Assuntos
Diabetes Mellitus Tipo 2 , Sobrepeso , Adulto , Humanos , Sobrepeso/complicações , Sobrepeso/terapia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Glicemia , Obesidade/complicações , Obesidade/epidemiologia , Obesidade/terapia , Estilo de Vida , Lipoproteínas LDL , Colesterol , Fatores de Risco
9.
iScience ; 27(1): 108763, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38261926

RESUMO

Respiratory syncytial virus (RSV) is a global healthcare problem, causing respiratory illness in young children and elderly individuals. Our knowledge of the host pathways that define susceptibility to infection and disease severity are limited. Hypoxia inducible factors (HIFs) define metabolic responses to low oxygen and regulate inflammatory responses in the lower respiratory tract. We demonstrate a role for HIFs to suppress RSV entry and RNA replication. We show that hypoxia and HIF prolyl-hydroxylase inhibitors reduce the expression of the RSV entry receptor nucleolin and inhibit viral cell-cell fusion. We identify a HIF regulated microRNA, miR-494, that regulates nucleolin expression. In RSV-infected mice, treatment with the clinically approved HIF prolyl-hydroxylase inhibitor, Daprodustat, reduced the level of infectious virus and infiltrating monocytes and neutrophils in the lung. This study highlights a role for HIF-signalling to limit multiple aspects of RSV infection and associated inflammation and informs future therapeutic approaches for this respiratory pathogen.

10.
Ann Noninvasive Electrocardiol ; 29(1): e13094, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38288511

RESUMO

OBJECTIVE: We aimed to investigate the association between visit-to-visit heart rate variability (VVHRV) and all-cause mortality in patients diagnosed with atrial fibrillation (AF). Previous studies have shown a positive correlation between VVHRV and several adverse outcomes. However, the relationship between VVHRV and the prognosis of AF remains uncertain. METHODS: In our study, we aimed to examine the relationship between VVHRV and mortality rates among 3983 participants with AF, who were part of the AFFIRM study (Atrial Fibrillation Follow-Up Investigation of Rhythm Management). We used the standard deviation of heart rate (HRSD) to measure VVHRV and divided the patients into four groups based on quartiles of HRSD (1st, <5.69; 2nd, 5.69-8.00; 3rd, 8.01-11.01; and 4th, ≥11.02). Our primary endpoint was all-cause death, and we estimated the hazard ratios for mortality using the Cox proportional hazard regressions. RESULTS: Our analysis included 3983 participants from the AFFIRM study and followed for an average of 3.5 years. During this period, 621 participants died from all causes. In multiple-adjustment models, we found that the lowest and highest quartiles of HRSD independently predicted an increased risk of all-cause mortality compared to the other two quartiles, presenting a U-shaped relationship (1st vs 2nd, hazard ratio = 2.28, 95% CI = 1.63-3.20, p < .01; 1st vs. 3rd, hazard ratio = 2.23, 95% CI = 1.60-3.11, p < .01; 4th vs. 2nd, hazard ratio = 1.82, 95% CI = 1.26-2.61, p < .01; and 4th vs. 3rd, hazard ratio = 1.78, 95% CI = 1.25-2.52, p < .01). CONCLUSION: In patients with AF, we found that both lower VVHRV and higher VVHRV increased the risk of all-cause mortality, indicating a U-shaped curve relationship.


Assuntos
Fibrilação Atrial , Humanos , Causalidade , Eletrocardiografia , Frequência Cardíaca/fisiologia , Prognóstico , Fatores de Risco , Mortalidade
11.
Polymers (Basel) ; 16(2)2024 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-38257028

RESUMO

Soft materials bearing rigid, lightweight, and vibration-dampening properties offer distinct advantages over traditional wooden and metal-based fillings for spent fuel transport casks, due to their low density, tunable structure, excellent mechanical properties, and ease of processing. In this study, a novel type of rigid polyurethane foam is prepared using a conventional polycondensation reaction between isocyanate and hydroxy groups. Moreover, the density and size of the pores in these foams are precisely controlled through simultaneous gas generation. The as-prepared polyurethane exhibits high thermal stability exceeding 185 °C. Lifetime predictions based on thermal testing indicate that these polyurethane foams could last up to over 60 years, which is double the lifetime of conventional materials of about 30 years. Due to their occlusive structure, the mechanical properties of these polymeric materials meet the design standards for spent fuel transport casks, with maximum compression and tensile stresses of 6.89 and 1.37 MPa, respectively, at a testing temperature of -40 °C. In addition, these polymers exhibit effective flame retardancy; combustion ceased within 2 s after removal of the ignition source. All in all, this study provides a simple strategy for preparing rigid polymeric foams, presenting them as promising prospects for application in spent fuel transport casks.

12.
Angew Chem Int Ed Engl ; 63(1): e202314833, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37994382

RESUMO

N-, C-, O-, S-coordinated single-metal-sites (SMSs) have garnered significant attention due to the potential for significantly enhanced catalytic capabilities resulting from charge redistribution. However, significant challenges persist in the precise design of well-defined such SMSs, and the fundamental comprehension has long been impeded in case-by-case reports using carbon materials as investigation targets. In this work, the well-defined molecular catalysts with N3 C1 -anchored SMSs, i.e., N-confused metalloporphyrins (NCPor-Ms), are calculated for their catalytic oxygen reduction activity. Then, NCPor-Ms with corresponding N4 -anchored SMSs (metalloporphyrins, Por-Ms), are synthesized for catalytic activity evaluation. Among all, NCPor-Co reaches the top in established volcano plots. NCPor-Co also shows the highest half-wave potential of 0.83 V vs. RHE, which is much better than that of Por-Co (0.77 V vs. RHE). Electron-rich, low band gap and regulated d-band center contribute to the high activity of NCPor-Co. This study delves into the examination of well-defined asymmetric SMS molecular catalysts, encompassing both theoretical and experimental facets. It serves as a pioneering step towards enhancing the fundamental comprehension and facilitating the development of high-performance asymmetric SMS catalysts.

13.
J Clin Endocrinol Metab ; 109(2): 581-591, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-37579499

RESUMO

BACKGROUND: The association between 25-hydroxyvitamin D and mortality remains controversial. Klotho, a biomarker of vitamin D activation and metabolism, may play a key role in this association. However, it is unclear whether the association between vitamin D deficiency and mortality risk is modified by klotho levels. Therefore, this study investigated the joint association of serum 25-hydroxyvitamin D [25(OH)D] and klotho with mortality risk in American community-dwelling adults. METHODS: A total of 9870 adults from the National Health and Nutrition Examination Survey (2007-2016) were included in our study. Mortality data were ascertained by linking participants to National Death Index records. Cox proportional hazards models were used to assess the association among serum 25(OH)D, serum klotho, and all-cause and cardiovascular disease (CVD) mortality. RESULTS: We found a significant interaction between klotho and serum 25(OH)D in all-cause mortality (P = .028). With klotho > 848.4 pg/mL (risk threshold on mortality), no significant all-cause and CVD mortality risk was observed at any level of serum 25(OH)D. However, with klotho < 848.4 pg/mL, a significant all-cause and CVD mortality risk was observed with serum 25(OH)D < 50 nmol/L [hazards ratio (HR), 1.36; 95% confidence interval (CI), 1.10-1.69; HR, 1.78; 95% CI, 1.16-3.45) and serum 25(OH)D of continuous variable (HR, 0.98; 95% CI, .97-.99; HR, 0.98; 95% CI, .98-.99). In addition, vitamin D metabolism disruption accessed by the combination of decreasing serum 25(OH)D (<50 nmol/L) and klotho (<848.4 pg/mL) was associated with significant all-cause mortality (HR, 1.48; 95% CI, 1.11-1.96) and CVD mortality (HR, 2.36; 95% CI, 1.48-3.75). CONCLUSIONS: Vitamin D-associated mortality risk is observed only with concurrently decreasing klotho, indicating that vitamin D metabolism dysfunction increases the risk of mortality. Klotho levels could help predict long-term mortality outcomes and thus may be useful concurrently for guiding vitamin D supplementation therapy decision-making in populations with vitamin D deficiency.


Assuntos
Doenças Cardiovasculares , Deficiência de Vitamina D , Adulto , Humanos , Inquéritos Nutricionais , Vitamina D , Calcifediol , Fatores de Risco
14.
Mayo Clin Proc ; 99(1): 90-101, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37690012

RESUMO

OBJECTIVE: To assess whether the presence of cardiac autonomic dysfunction denoted by low heart rate variability (HRV) modifies the effect of intensive glycemic therapy on outcomes in patients with type 2 diabetes. PATIENTS AND METHODS: This study included 7946 participants in the ACCORD (Action to Control Cardiovascular Risk in Diabetes) trial from January 2001 through June 2009. Heart rate variability measures included standard deviation of all normal-to-normal intervals (SDNN) and root mean square of successive differences between normal-to-normal intervals (rMSSD). Abnormal values were defined based on less than the 10th percentile for SDNN and rMSSD. RESULTS: Compared with standard therapy, intensive therapy was associated with improved primary outcome (composite of cardiovascular events) in the low-HRV group (SDNN: HR, 0.57; 95% CI, 0.39 to 0.84; rMSSD: HR, 0.57; 95% CI, 0.38 to 0.84), but not in the normal-HRV group (SDNN: HR, 0.90; 95% CI, 0.77 to 1.05; rMSSD: HR, 0.90; 95% CI, 0.77 to 1.05). A similar pattern was found for coronary heart disease. Conversely, intensive therapy had a neutral effect on all cause death in the low-HRV group (SDNN: HR, 0.88; 95% CI, 0.54 to 1.41; rMSSD: HR, 0.71; 95% CI, 0.43 to 1.17;), but increase risk of all-cause death in the normal-HRV group (SDNN: HR, 1.21; 95% CI, 1.00 to 1.46; rMSSD: HR, 1.25; 95% CI, 1.03 to 1.51). Intensive therapy induced a greater risk of hypoglycemia in the normal-HRV group than that in the low-HRV group. CONCLUSION: Cardiac autonomic dysfunction expressed as low HRV identified subpopulations in ACCORD with more benefits and less harms from intensive therapy.


Assuntos
Doenças do Sistema Nervoso Autônomo , Diabetes Mellitus Tipo 2 , Humanos , Sistema Nervoso Autônomo , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Coração , Frequência Cardíaca/fisiologia
15.
Diabetes Metab Syndr ; 18(1): 102930, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38150792

RESUMO

AIMS: Heart rate variability (HRV) and resting heart rate (RHR) are usually analyzed and interpreted separately. We aimed to assess the interplay of HRV and RHR on mortality in type 2 diabetes. METHODS: The study included 7,529 participants from the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial. HRV metrics included standard deviation of all normal-to-normal intervals (SDNN) and root mean square of successive differences between normal-to-normal intervals (rMSSD). Abnormal values were defined based on <25th percentile for HRV and >75th percentile for RHR. Interactions of HRV status and RHR status were tested on multiplicative and additive scales. Results were validated in a subset of patients with type 2 diabetes (n = 745) from the Multi-Ethnic Study of Atherosclerosis. RESULTS: Low SDNN was associated with increased all-cause mortality in the high RHR group (HR 1.60; 95% CI 1.29-1.97), but not in the normal RHR group. Compared with those who had neither low SDNN nor high RHR, the presence of either low SDNN or high RHR was not significantly associated with an increased risk of all-cause mortality. In contrast, the combination of low SDNN and high RHR was associated with a significantly increased risk of all-cause mortality (HR 1.68; 95% CI 1.43-1.97). Significant multiplicative and additive interactions were found between HRV status and RHR status on risk of all-cause mortality (all Pinteraction < 0.05). Similar findings were observed for cardiovascular mortality, in analyses using rMSSD, and in the Multi-Ethnic Study of Atherosclerosis. CONCLUSIONS: The association between HRV and mortality risk is modified by RHR levels. Furthermore, low HRV and high RHR have interdependent and synergistic associations with mortality risk.


Assuntos
Aterosclerose , Diabetes Mellitus Tipo 2 , Humanos , Frequência Cardíaca/fisiologia , Diabetes Mellitus Tipo 2/complicações , Coração
16.
Eur J Prev Cardiol ; 31(4): 461-469, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38123512

RESUMO

AIMS: Achieving at least 150 min per week of moderate-to-vigorous physical activity (PA) is a 'Class I, A level' recommendation for the primary prevention of cardiovascular disease. However, long-term PA is a complex behaviour and varied by lifetime, which was insufficiently reflected by the current studies. This study used time-in-target range (TTR) to measure the long-term PA level during young adulthood and investigated its relationship with cardiovascular events in later life. METHODS AND RESULTS: Participants in the Coronary Artery Risk Development in Young Adults study were recruited (n = 2902) and allocated into four groups by PA TTR: <25% (n = 1028), 25 to <50% (n = 444), 50 to <75% (n = 424), 75 to 100% (n = 1006). TTR was estimated with linear interpolation across the first 15 years. The primary outcome was a composite of cardiovascular events. The mean (SD) age after the exposure period was 40.3 (3.6) years. After a median follow-up for an additional 18.9 years, the participants with a TTR of at least 75% had a 40% lower risk of the primary outcome (HR: 0.60; 95%CI: 0.38 to 0.95) compared with the lowest TTR group. Each 1-SD increase in TTR was also significantly associated with a 21% decreased risk of the primary outcome (HR: 0.79; 95%CI: 0.65-0.97). CONCLUSION: Increasing PA is essential in young adulthood. In young adults, maintaining long-term guidelines-recommended PA levels may help to lower the risk of cardiovascular events in later life. Maintaining the guidelines-recommended PA level for at least 75% of time across young adulthood may be preferable.


Maintaining long-term guidelines-recommended PA levels may decrease the risk of cardiovascular events in later life, and young adults maintaining that PA level for at least 75% of time may be preferable.


Assuntos
Doenças Cardiovasculares , Exercício Físico , Humanos , Adulto Jovem , Adulto , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle
17.
J Cachexia Sarcopenia Muscle ; 15(1): 342-351, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38108096

RESUMO

BACKGROUND: Patients with overweight/obesity and type 2 diabetes are encouraged to lose weight, but not all losing weight gain better cardiovascular health, especially old adults. The change in skeletal muscle mass (SMM) could be the key that explains the heterogenous cardiovascular effects of weight loss. This study aims to assess whether the cardiovascular effects of weight loss vary for those gaining skeletal muscle along with weight loss. METHODS: The old adults with overweight/obesity and type 2 diabetes in the Look AHEAD study having muscle measurement from dual-energy X-ray absorptiometry were included. Based on the weight change (WC) and SMM change (SMMC) between baseline and the 4-year follow-up, participants were allocated into three groups-weight gain (WG) group, weight loss with muscle loss (WL-ML) group and weight loss with muscle gain (WL-MG) group. Cox proportional hazards regression was performed to evaluate the cardiovascular risk of those gaining or losing SMM with weight loss compared with those gaining weight. Among the participants with weight loss, the ratio of SMMC/WC was calculated, and the association of SMMC/WC with primary cardiovascular outcome was assessed. RESULTS: A total of 491 participants were included in the study with an average age of 64.56 ± 3.81 years old. A total of 47.0% were male and 49.9% were from the intensive lifestyle intervention arm. Based on their WC and SMMC, 43 were assigned to the WG group, 373 to the WL-ML group and 75 to the WL-MG group. Over a follow-up of almost 10 years, 97 participants encountered the primary endpoint. The WG group had the highest incidence of 25.59%, the WL-MG group had the lowest incidence of 9.33% and the WL-ML group had 21.18% (P = 0.040). In the fourth adjusted Cox model, the WL-MG group achieved significantly decreased odds of the primary endpoint compared with the WG group (hazard ratio [HR] 0.33, 95% confidence interval [CI] [0.12, 0.87], P = 0.026), whilst the WL-ML group did not (HR 0.91, 95% CI [0.47, 1.78], P = 0.670). Among the participants with weight loss, when SMMC/WC reached around 50%, this HR soared to approximately two-fold. CONCLUSIONS: The participants gaining SMM along with weight loss achieved the lowest odds of adverse cardiovascular events, whilst those who lost SMM along with weight loss had comparable cardiovascular risk with those gaining weight. The more muscle lost during weight loss, the greater the harm. The cardiovascular effects of weight loss were modulated by whether the participants gained SMM meanwhile losing weight.


Assuntos
Diabetes Mellitus Tipo 2 , Sobrepeso , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Feminino , Sobrepeso/complicações , Diabetes Mellitus Tipo 2/complicações , Obesidade/complicações , Obesidade/epidemiologia , Redução de Peso , Aumento de Peso , Músculo Esquelético
18.
J Am Chem Soc ; 145(49): 26871-26882, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-37968832

RESUMO

Two-dimensional (2D) covalent organic frameworks (COFs) with hierarchical porosity have been increasingly recognized as promising materials in various fields. Besides, the 2D COFs with kagome (kgm) topology can exhibit unique optoelectronic features and have extensive applications. However, rational synthesis of the COFs with kgm topology remains challenging because of competition with a square-lattice topology. Herein, we report two isomeric dual-pore 2D COFs with kgm topology using a novel geometric strategy to reduce the symmetry of their building blocks, which are four-armed naphthalene-based and azulene-based isomeric monomers. Owing to the large dipole moment of azulene, as-prepared azulene-based COF (COF-Az) possesses a considerably narrow band gap of down to 1.37 eV, which is much narrower than the naphthalene-based 2D COF (COF-Nap: 2.28 eV) and is the lowest band gap among reported imine-linked dual-pore 2D COFs. Moreover, COF-Az was used as electrode material in a gas sensor and exhibits high selectivity for NO2, including a high response rate (58.7%) to NO2 (10 ppm), fast recovery (72 s), up to 10 weeks of stability, and resistance to 80% relative humidity, which are superior to those of reported COF-based NO2 gas sensors. The calculation and in situ experimental results indicate that the large dipole moment of azulene boosts the sensitivity of the imine linkages. The usage of isomeric building blocks not only enables the synthesis of 2D COFs with isometric kgm topology but also provides an azulene-based 2D platform for studying the structure-property correlations of COFs.

19.
Int J Pharm ; 648: 123580, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37944677

RESUMO

The supercritical antisolvent-fluidized bed coating process (SAS-FB) shows great potential as a technique to manufacture dry powder inhaler (DPI) that incorporate nanodrugs onto micronized matrix particles, capitalizing on the merits of both nanoparticle and pulmonary delivery. In this study, naringin (NAR), a pharmacologically active flavonoid with low solubility and in vivo degradation issues, was utilized as a model active pharmaceutical ingredient to construct nanomedicine-based DPI through SAS-FB. It is showed that processed NAR exhibited a near-spherical shape and an amorphous structure with an average size of around 130 nm. Notably, SAS-FB products prepared with different fluidized matrices resulted in varying deposition patterns, particularly when mixed with a coarse lactose to enhance the fine particle fraction (FPF) of the formulations. The FPF was positively associated with specific surface area of the SAS-FB products, while the specific surface area was directly related to surface roughness and particle size. In vitro dissolution studies using simulated lung fluid revealed that the NAR nanoparticles coated on the products were released immediately upon contact with solution, with a cumulative dissolution exceeding 90% within the first minute. Importantly, compared to oral raw NAR, the optimized DPI formulation demonstrated superior in vivo plasmatic and pulmonary AUC0→∞ by 51.33-fold and 104.07-fold respectively in a Sprague-Dawley rat model. Overall, SAS- FB technology provides a practical approach to produce nanomedicine DPI product that combine the benefits of nanoparticles with the aerodynamics properties of inhaled microparticles.


Assuntos
Inaladores de Pó Seco , Nanomedicina , Ratos , Animais , Inaladores de Pó Seco/métodos , Ratos Sprague-Dawley , Administração por Inalação , Pulmão , Tamanho da Partícula , Pós
20.
Circ Cardiovasc Imaging ; 16(11): e015589, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37988449

RESUMO

BACKGROUND: Recent studies have shown that remnant cholesterol (RC) is associated with incident heart failure; however, its association with left ventricular (LV) structure and function is unclear. We aimed to evaluate the association between RC levels in young adulthood and LV structure and function in middle age. METHODS: We included 3321 participants from the CARDIA study (Coronary Artery Risk Development in Young Adults) at baseline. RC was calculated as total cholesterol minus high-density lipoprotein cholesterol minus calculated low-density lipoprotein cholesterol, and the RC trajectories that followed a similar pattern of change over time were identified using the latent class growth mixture model. LV structure and function were assessed using echocardiography at CARDIA study year 25. Multivariable linear regression models were performed to assess the associations of both baseline and trajectories of RC levels with LV structure and function. RESULTS: Among 3321 participants, the mean age was 24.99±3.62 years: 1450 (43.90%) were male, and 1561 (47.00%) were Black. After multivariate adjustment, higher baseline RC (per SD in log-transformed) was associated with higher LV mass index (ß=1.29; P=0.004), worse global longitudinal strain (ß=0.19; P<0.001), worse global circumferential strain (ß=0.16; P=0.014), lower septal e' (ß=-0.26; P<0.001), lower lateral e' (ß=-0.18; P=0.003), and higher E/e' (ß=0.15; P=0.003). Three RC trajectories were identified during follow-up: low increasing (42.4%), moderate increasing (45.5%), and high increasing (12.1%). Similarly, compared with the low-increasing group, the high-increasing RC trajectory group was related to higher LV mass index, worse global longitudinal strain, lower septal e', lower lateral e', and higher E/e'. CONCLUSIONS: Elevated RC levels in young adulthood were related to adverse LV structural and functional alterations in midlife. Long-term trajectories of RC levels during young adulthood help identify individuals at a higher risk for adverse LV remodeling and dysfunction. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT00005130.


Assuntos
Disfunção Ventricular Esquerda , Função Ventricular Esquerda , Adulto Jovem , Humanos , Masculino , Pessoa de Meia-Idade , Adulto , Feminino , Fatores de Risco , Remodelação Ventricular , Ecocardiografia , Colesterol , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/epidemiologia
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