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1.
Nature ; 630(8018): 878-883, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38718837

RESUMO

The properties of polycrystalline materials are often dominated by defects; two-dimensional (2D) crystals can even be divided and disrupted by a line defect1-3. However, 2D crystals are often required to be processed into films, which are inevitably polycrystalline and contain numerous grain boundaries, and therefore are brittle and fragile, hindering application in flexible electronics, optoelectronics and separation1-4. Moreover, similar to glass, wood and plastics, they suffer from trade-off effects between mechanical strength and toughness5,6. Here we report a method to produce highly strong, tough and elastic films of an emerging class of 2D crystals: 2D covalent organic frameworks (COFs) composed of single-crystal domains connected by an interwoven grain boundary on water surface using an aliphatic bi-amine as a sacrificial go-between. Films of two 2D COFs have been demonstrated, which show Young's moduli and breaking strengths of 56.7 ± 7.4 GPa and 73.4 ± 11.6 GPa, and 82.2 ± 9.1 N m-1 and 29.5 ± 7.2 N m-1, respectively. We predict that the sacrificial go-between guided synthesis method and the interwoven grain boundary will inspire grain boundary engineering of various polycrystalline materials, endowing them with new properties, enhancing their current applications and paving the way for new applications.

2.
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.

3.
Small ; : e2405974, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39148200

RESUMO

2D conjugated covalent organic frameworks (c-COFs) provide an attractive foundation as organic electrodes in energy storage devices, but their storage capability is long hindered by limited ion accessibility within densely π-π stacked interlayers. Herein, two kinds of 2D c-COFs based on dioxin and dithiine linkages are reported, which exhibit distinct in-plane configurations-fully planar and undulated layers. X-ray diffraction analysis reveals wavy square-planar networks in dithiine-bridged COF (COF-S), attributed to curved C─S─C bonds in the dithiine linkage, whereas dioxin-bridged COF (COF-O) features densely packed fully planar layers. Theoretical and experimental results elucidate that the undulated stacking within COF-S possesses an expanded layer distance of 3.8 Å and facilitates effective and rapid Li+ storage, yielding a superior specific capacity of 1305 mAh g-1 at 0.5 A g-1, surpassing that of COF-O (1180 mAh g-1 at 0.5 A g-1). COF-S also demonstrates an admirable cycle life with 80.4% capacity retention after 5000 cycles. As determined, self-expanded wavy-stacking geometry, S-enriched dithiine in COF-S enhances the accessibility and redox activity of Li storage, allowing each phthalocyanine core to store 12 Li+ compared to 8 Li+ in COF-O. These findings underscore the elements and stacking modes of 2D c-COFs, enabling tunable layer distance and modulation of accessible ions.

4.
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
5.
Med Teach ; : 1-9, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38818632

RESUMO

BACKGROUND: It is unclear whether alternating placements during clinical clerkship, without an explicit emphasis on clinical competencies, would bring about optimal educational outcomes. METHODS: This is an explanatory sequential mixed-methods research. We enrolled a convenience sample of 41 eight-year programme medical students in Sun Yat-sen University who received alternating placements during clerkship. The effects of competence-based approach (n = 21) versus traditional approach (n = 20) to clerkship teaching were compared. In the quantitative phase, course satisfaction was measured via an online survey and academic performance was determined through final scores on summative assessment. Then, in the qualitative phase, students were invited for semi-structured interviews about their learning experiences, and the transcripts were used for thematic analysis. RESULTS: Quantitative findings showed that students in the study group rated high course satisfaction and performed significantly better in their final scores compared with those in the control group. Qualitative findings from thematic analysis showed that students were relatively neutral about their preference on placement models, but clearly perceived, capitalised, and appreciated that their competencies were being cultivated by an instructor who was regarded as a positive role model. CONCLUSION: A competence-based approach to clerkship teaching resulted in better course satisfaction and academic performance, and was perceived, capitalised, and appreciated by students.

6.
Chempluschem ; 89(6): e202300782, 2024 Jun.
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.

7.
J Colloid Interface Sci ; 675: 683-688, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38996698

RESUMO

Asymmetric nitrogen/carbon-coordinated single metal sites (M-NxC4-x) outperform symmetric M-N4 sites in carbon dioxide (CO2) electroreduction. However, the challenge of crafting well-defined M-NxC4-x sites complicates the understanding of their structure-catalytic performance relationship. In this study, we employ metallized N-confused tetraphenylporphyrin (M-NCTPP) to investigate CO2 conversion on M-N3C1 sites using both density functional theory and experimental methods. The optimal cobalt (Co)-N3C1 site (Co-NCTPP) achieves a current density of 500 mA cm-2 and a carbon monoxide Faraday efficiency exceeding 90 % at -1.25 V vs. the reversible hydrogen electrode, surpassing the performance of Co-N4 (Co-TPP). This research introduces a novel approach for designing and synthesizing high-activity heteroatom-anchored single metal sites, advancing fundamental understanding in the field.

8.
Eur J Prev Cardiol ; 31(9): 1173-1182, 2024 Jul 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 (CVDs), but data about the prognostic significance of multiple cardiovascular calcifications are limited. We aim to investigate the interaction relationship between AVC and CAC for major events. METHODS AND RESULTS: We included 6695 participants from the Multi-Ethnic Study of Atherosclerosis at baseline and divided them into four groups: (i) no AVC or CAC; (ii) only AVC; (iii) only CAC; and (iv) with CAC and CAC. The Cox regression model and the Kaplan-Meier method were used to analyse CVD outcomes. We evaluated the interaction between AVC and CAC and their added predictive value based on the pooled cohort equations (PCEs). Subgroup analyses were also explored. Among 6695 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 [hazard ratio = 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 analyses. The addictive interaction was statistically significant (P < 0.001). When AVC and CAC were added, the predictive value of PCEs increased. CONCLUSION: Our results indicated a synergistic interaction between valve calcification and coronary calcification in CVDs. Management for both AVC and CAC may bring health co-benefits in preventing poor outcomes.


We investigated the interaction relationship between aortic valve calcification (AVC) and coronary artery calcification (CAC) in 6695 participants with measurements for cardiovascular calcifications at baseline in the 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 is necessary to implement earlier and more positive intervention for cardiovascular disease prevention in this certain subpopulation.


Assuntos
Valva Aórtica , Calcinose , Doença da Artéria Coronariana , Calcificação Vascular , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/patologia , Prognóstico , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/mortalidade , Idoso , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/epidemiologia , Medição de Risco , Calcinose/diagnóstico por imagem , Calcinose/epidemiologia , Fatores de Risco , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/epidemiologia , Estados Unidos/epidemiologia , Fatores de Tempo , Estudos Prospectivos , Valvopatia Aórtica/epidemiologia , Valor Preditivo dos Testes
9.
Endocrine ; 85(3): 1213-1221, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38904908

RESUMO

BACKGROUND: Previous studies have shown that increasing body mass index (BMI) was associated with decreased hypoglycemia in type 2 diabetes, but it remains uncertain whether this finding could be applied to patients with and without cardiac autonomic neuropathy (CAN). METHODS: The study included 7789 participants with type 2 diabetes from action to control cardiovascular risk in diabetes (ACCORD) trail. CAN was defined as SDNN < 8.2 ms and RMSSD < 8.0 ms. Obesity was defined as BMI ≥ 30 kg/m2. Outcomes were identified as severe hypoglycemia requiring any assistance (HAA) or requiring medical assistance (HMA). We assessed the association between obesity and severe hypoglycemia in type 2 diabetes with or without CAN using COX regression models adjusted for baseline characteristics. RESULTS: Over a median follow-up of 4.7 years, a total of 893 participants developed HAA and 584 participants developed HMA. Compared with non-obesity, obesity was associated with lower risk of severe hypoglycemia (HAA: hazard ratio [HR] 0.51, 95% confidence interval [CI] 0.38-0.68, P < 0.001; HMA: HR 0.57, 95% CI 0.40-0.82, P = 0.002) in CAN present group, but not in CAN absent group (HAA: HR 0.98, 95% CI 0.83-1.16, P = 0.830; HMA: HR 0.97, 95% CI 0.79-1.19, P = 0.754). Similarly, increasing BMI was associated with reduced severe hypoglycemic events in participants with CAN, but not in participants without CAN. CONCLUSIONS: CAN modifies the association between obesity and hypoglycemia in type 2 diabetes. Type 2 diabetic individuals with CAN who are under weight control should pay attention to hypoglycemic events. TRIAL REGISTRY: http://www. CLINICALTRIALS: gov . Unique identifier: NCT00000620.


Assuntos
Diabetes Mellitus Tipo 2 , Neuropatias Diabéticas , Hipoglicemia , Obesidade , Humanos , Diabetes Mellitus Tipo 2/complicações , Masculino , Pessoa de Meia-Idade , Feminino , Obesidade/complicações , Hipoglicemia/epidemiologia , Hipoglicemia/complicações , Idoso , Neuropatias Diabéticas/etiologia , Neuropatias Diabéticas/epidemiologia , Índice de Massa Corporal , Doenças do Sistema Nervoso Autônomo/etiologia , Doenças do Sistema Nervoso Autônomo/epidemiologia
10.
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
11.
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.

12.
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
13.
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
14.
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
15.
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.

16.
J Am Heart Assoc ; 13(14): e032904, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38979831

RESUMO

BACKGROUND: Cardiac aging represents an independent risk factor for aging-associated cardiovascular diseases. Although evidence suggests an association between NOD-, LRR-, and pyrin domain-containing protein 3 (NLRP3) inflammasome formation and numerous cardiovascular diseases, its role in cardiac aging remains largely unclear. METHODS AND RESULTS: The longevity of mice with wild-type and NLRP3 knockout (NLRP3-/-) genotypes was assessed, with or without d-galactose treatment. Cardiac function was evaluated using echocardiography, and cardiac histopathology was examined through hematoxylin and eosin and Masson's trichrome staining. Senescence-associated ß-galactosidase (SA-ß-gal) staining was employed to detect cardiac aging. Western blotting was used to assess aging-related proteins (p53, p21) and pyroptosis-related proteins. Additionally, dihydroethidium staining, lactate dehydrogenase release, and interleukin-1ß ELISA assays were performed, along with measurements of total superoxide dismutase and malondialdehyde levels. In vitro, H9c2 cells were exposed to d-galactose for 24 hours in the absence or presence of N-acetyl-l-cysteine (reactive oxygen species inhibitor), BAY-117082 (nuclear factor κ-light-chain enhancer of activated B cells inhibitor), MCC950 (NLRP3 inhibitor), and VX-765 (Caspase-1 inhibitor). Immunofluorescence staining was employed to detect p53, gasdermin D, and apoptosis-associated speck-like protein proteins. Intracellular reactive oxygen species levels were assessed using fluorescence microscopy and flow cytometry. Senescence-associated ß-galactosidase staining and Western blotting were also employed in vitro for the same purpose. The results showed that NLRP3 upregulation was implicated in aging and cardiovascular diseases. Inhibition of NLRP3 extended life span, mitigated the aging phenotype, improved cardiac function and blood pressure, ameliorated lipid metabolism abnormalities, inhibited pyroptosis in cardiomyocytes, and ultimately alleviated cardiac aging. In vitro, the inhibition of reactive oxygen species, nuclear factor κ-light-chain enhancer of activated B cells, NLRP3, or caspase-1 attenuated NLRP3 inflammasome-mediated pyroptosis. CONCLUSIONS: The reactive oxygen species/nuclear factor κ-light-chain enhancer of activated B cells/NLRP3 signaling pathway loop contributes to d-galactose-treated cardiomyocyte senescence and cardiac aging.


Assuntos
Galactose , Inflamassomos , Camundongos Knockout , Miócitos Cardíacos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Piroptose , Animais , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Galactose/toxicidade , Galactose/metabolismo , Piroptose/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Inflamassomos/metabolismo , Camundongos , Envelhecimento/metabolismo , Camundongos Endogâmicos C57BL , Transdução de Sinais , Senescência Celular/efeitos dos fármacos , Masculino , Espécies Reativas de Oxigênio/metabolismo , NF-kappa B/metabolismo , Linhagem Celular , Modelos Animais de Doenças , Ratos
17.
Chemosphere ; 364: 143086, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39146990

RESUMO

The risk of chronic inflammatory diseases has been linked to exposure to polycyclic aromatic hydrocarbons (PAHs). However, limited data are available regarding their impact on periodontitis. This study aims to explore the association between PAHs and periodontitis while also evaluating the potential modifying effects of healthy lifestyles. We included 17,031 participants from the US National Health and Nutrition Examination Survey (NHANES, 2001-2004 and 2009-2014). A meta-analysis-based environment-wide association study (EWAS) was adopted to identify environmental chemicals for the mean probing pocket depth (PPD) and the mean attachment loss (AL). PAHs were further evaluated concerning the cross-sectional association with Mod/Sev periodontitis using multivariable logistic regression models. Moreover, healthy lifestyle scores were estimated to assess their modifying effect on the PAH-periodontitis association. EWAS analysis identified several urinary PAH metabolites as significant risk factors for the mean PPD and AL (false discovery rate <0.05, Q > 0.05). Periodontitis severity was positively associated with eight individual and total PAH concentrations. Stratifying the participants in terms of healthy lifestyle scores did not reveal any association in the healthy group. Moreover, the association weakened in never-smokers and individuals with sufficient physical activity and normal weight. PAH exposure was a risk factor for periodontitis. A healthier lifestyle was observed to offset the risk potentials of PAHs for periodontitis. Smoking cessation, physical activity, and weight loss might be recommended as a healthy lifestyle strategy for ameliorating PAH-related periodontitis.

18.
Adv Mater ; : e2407128, 2024 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-39129345

RESUMO

Compared to lithium (Li) anode, the alloy/Li-alloy anodes show more compatible with sulfide solid electrolytes (SSEs), and are promising candidates for practical SSE-based all-solid-state Li batteries (ASSLBs). In this work, a porous Li-Al alloy (LiAl-p) anode is crafted using a straightforward mechanical pressing method. Various characterizations confirm the porous nature of such anode, as well as rich oxygen species on its surface. To the best knowledge, such LiAl-p anode demonstrates the best room temperature cell performance in comparison with reported Li and alloy/Li-alloy anodes in SSE-based ASSLBs. For example, the LiAl-p symmetric cells deliver a record critical current density of 6.0 mA cm-2 and an ultralong cycling of 5000 h; the LiAl-p|LiNi0.8Co0.1Mn0.1O2 full cells achieve a high areal capacity of 11.9 mAh cm-2 and excellent durability of 1800 cycles. Further in situ and ex situ experiments reveal that the porous structure can accommodate volume changes of LiAl-p and ensure its integrity during cycling; and moreover, a robust Li inorganics-rich solid electrolyte interphase can be formed originated from the reaction between SSE and surface oxygen species of LiAl-p. This study offers inspiration for designing high-performance alloy anodes by focusing on designing special architecture to alleviate volume change and constructing stable interphase.

19.
Pharmaceuticals (Basel) ; 17(4)2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38675374

RESUMO

Supercritical anti-solvent fluidized bed (SAS-FB) coating technology has the advantages of reducing particle size, preventing high surface energy particle aggregation, improving the dissolution performance and bioavailability of insoluble drugs. The poor solubility of Biopharmaceutics Classification System (BCS) class IV drugs poses challenges in achieving optimal bioavailability. Numerous anti-cancer drugs including paclitaxel (PTX) belong to the BCS class IV, hindering their therapeutic efficacy. To address this concern, our study explored SAS-FB technology to coat PTX with D-α-tocopherol polyethylene glycol 1000 succinate (TPGS) onto lactose. Under our optimized conditions, we achieved a PTX coating efficiency of 96.8%. Further characterization confirmed the crystalline state of PTX in the lactose surface coating by scanning electron microscopy and X-ray powder diffraction. Dissolution studies indicated that SAS-FB processed samples release over 95% of the drug within 1 min. Moreover, cell transmembrane transport assays demonstrated that SAS-FB processed PTX samples co-coated with TPGS had an enhanced PTX internalization into cells and a higher permeability coefficient compared to those without TPGS. Finally, compared to unprocessed PTX, SAS-FB (TPGS) and SAS-FB processed samples showed a 2.66- and 1.49-fold increase in oral bioavailability in vivo, respectively. Our study highlights the efficacy of SAS-FB co-coating for PTX and TPGS as a promising strategy to overcome bioavailability challenges inherent in BCS class IV drugs. Our approach holds broader implications for enhancing the performance of similarly classified medications.

20.
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
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