Nanozymes for the Therapeutic Treatment of Diabetic Foot Ulcers.

Diabetic foot ulcers (DFU) are chronic, refractory wounds caused by diabetic neuropathy, vascular disease, and bacterial infection, and have become one of the most serious and persistent complications of diabetes mellitus because of their high incidence and difficulty in healing. Its malignancy results from a complex microenvironment that includes a series of unfriendly physiological states secondary to hyperglycemia, such as recurrent infections, excessive oxidative stress, persistent inflammation, and ischemia and hypoxia. However, current common clinical treatments, such as antibiotic therapy, insulin therapy, surgical debridement, and conventional wound dressings all have drawbacks, and suboptimal outcomes exacerbate the financial and physical burdens of diabetic patients. Therefore, development of new, effective and affordable treatments for DFU represents a top priority to improve the quality of life of diabetic patients. In recent years, nanozymes-based diabetic wound therapy systems have been attracting extensive interest by integrating the unique advantages of nanomaterials and natural enzymes. Compared with natural enzymes, nanozymes possess more stable catalytic activity, lower production cost and greater maneuverability. Remarkably, many nanozymes possess multienzyme activities that can cascade multiple enzyme-catalyzed reactions simultaneously throughout the recovery process of DFU. Additionally, their favorable photothermal-acoustic properties can be exploited for further enhancement of the therapeutic effects. In this review we first describe the characteristic pathological microenvironment of DFU, then discuss the therapeutic mechanisms and applications of nanozymes in DFU healing, and finally, highlight the challenges and perspectives of nanozyme development for DFU treatment.

The prognostic value of prognostic nutritional index in postoperative onset of PAH in children with isolated VSD: a prospective cohort study based on propensity score matching analysis.

Background: The mechanism of pulmonary arterial hypertension (PAH) after surgery/intervention for isolated venticlular septal defect (VSD) in children is unknown. Reliable prognostic indicators for predicting postoperative PAH are urgently needed. Prognostic nutration index (PNI) is widely used to predict postoperative complications and survival in adults, but it is unclear whether it can be used as an indicator of prognosis in children. Methods: A total of 251 children underwent VSD repair surgery or interventional closure in Hunan Children's Hospital from 2020 to 2023 were collected. A 1:1 propensity score matching (PSM) analysis was performed using the nearest neighbor method with a caliper size of 0.2 Logistics regression analysis is used to examine factors associated with the development of PAH. Results: The cut-off value for PNI was determined as 58.0. After 1:1 PSM analysis, 49 patients in the low PNI group were matched with high PNI group. Children in the low PNI group had higher risk of postoperative PAH (P = 0.002) than those in the high PNI group. Multivariate logistics regression analysis showed that PNI (RR: 0.903, 95% CI: 0.816-0.999, P = 0.049) and tricuspid regurgitation velocity (RR: 4.743, 95% CI: 1.131-19.897, P = 0.033) were independent prognostic factors for the development of PAH. Conclusion: PNI can be used as a prognostic indicator for PAH development after surgery/intervention in children with isolated VSD.

GLP-1 receptor agonists and myocardial metabolism in atrial fibrillation.

Atrial fibrillation (AF) is the most common cardiac arrhythmia. Many medical conditions, including hypertension, diabetes, obesity, sleep apnea, and heart failure (HF), increase the risk for AF. Cardiomyocytes have unique metabolic characteristics to maintain adenosine triphosphate production. Significant changes occur in myocardial metabolism in AF. Glucagon-like peptide-1 receptor agonists (GLP-1RAs) have been used to control blood glucose fluctuations and weight in the treatment of type 2 diabetes mellitus (T2DM) and obesity. GLP-1RAs have also been shown to reduce oxidative stress, inflammation, autonomic nervous system modulation, and mitochondrial function. This article reviews the changes in metabolic characteristics in cardiomyocytes in AF. Although the clinical trial outcomes are unsatisfactory, the findings demonstrate that GLP-1 RAs can improve myocardial metabolism in the presence of various risk factors, lowering the incidence of AF.

Deciphering antifungal and antibiofilm mechanisms of isobavachalcone against Cryptococcus neoformans through RNA-seq and functional analyses.

Cryptococcus neoformans has been designated as critical fungal pathogens by the World Health Organization, mainly due to limited treatment options and the prevalence of antifungal resistance. Consequently, the utilization of novel antifungal agents is crucial for the effective treatment of C. neoformans infections. This study exposed that the minimum inhibitory concentration (MIC) of isobavachalcone (IBC) against C. neoformans H99 was 8 µg/mL, and IBC dispersed 48-h mature biofilms by affecting cell viability at 16 µg/mL. The antifungal efficacy of IBC was further validated through microscopic observations using specific dyes and in vitro assays, which confirmed the disruption of cell wall/membrane integrity. RNA-Seq analysis was employed to decipher the effect of IBC on the C. neoformans H99 transcriptomic profiles. Real-time quantitative reverse transcription PCR (RT-qPCR) analysis was performed to validate the transcriptomic data and identify the differentially expressed genes. The results showed that IBC exhibited various mechanisms to impede the growth, biofilm formation, and virulence of C. neoformans H99 by modulating multiple dysregulated pathways related to cell wall/membrane, drug resistance, apoptosis, and mitochondrial homeostasis. The transcriptomic findings were corroborated by the antioxidant analyses, antifungal drug sensitivity, molecular docking, capsule, and melanin assays. In vivo antifungal activity analysis demonstrated that IBC extended the lifespan of C. neoformans-infected Caenorhabditis elegans. Overall, the current study unveiled that IBC targeted multiple pathways simultaneously to inhibit growth significantly, biofilm formation, and virulence, as well as to disperse mature biofilms of C. neoformans H99 and induce cell death.

Triglyceride to high-density lipoprotein cholesterol ratio associated with long-term adverse clinical outcomes in patients deferred revascularization following fractional flow reserve.

BACKGROUND: Guidelines on coronary intermediate lesions strongly recommend deferred revascularization after detecting a normal fractional flow reserve (FFR). Researches about triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) on cardiovascular diseases has also been well conducted. However, the association of TG/HDL-C and long-term adverse clinical outcomes remains unknown for patients deferred revascularization following FFR. METHODS: This study retrospectively included 374 coronary artery disease (CAD) patients with non-significant coronary lesions diagnosed by coronary angiography (CAG) and FFR. The main outcome measure was the combination of major adverse cardiovascular and cerebrovascular events (MACCEs). All patients were categorized into three subgroups in terms of TG/HDL-C tertiles (T1 < 0.96, 0.96 ≤ T2 < 1.58, T3 ≥ 1.58). Three different Cox regression models were utilized to reveal the association between TG/HDL-C and prevalence of MACCEs. RESULTS: 47 MACCEs were recorded throughout a median monitoring period of 6.6 years. The Kaplan-Meier survival curves showed a higher MACCEs rate occurred in the higher TG/HDL-C group (5.6% vs. 12.9% vs. 19.4%, log-rank P < 0.01). After adjustment, patients in T3 suffered a 2.6-fold risk compared to the T1 group (T3 vs. T1: HR 2.55, 95% CI 1.05-6.21, P = 0.038; T2 vs. T1: HR 1.71, 95% CI 0.65-4.49, P = 0.075; P for trend = 0.001). The restricted cubic spline (RCS) analysis demonstrated that the HR for MACCEs rose as TG/HDL-C increased. Both the receiver operating characteristic (ROC) and time-dependent ROC proved the excellent predictive ability of TG/HDL-C. CONCLUSION: The study illustrates that TG/HDL-C correlates with the risk of MACCEs in CAD patients deferred revascularization following FFR. TG/HDL-C could serve as a dependable predictor of cardiovascular events over the long term in this population.

Spermidine-Functionalized Injectable Hydrogel Reduces Inflammation and Enhances Healing of Acute and Diabetic Wounds In Situ.

The inflammatory response is a key factor affecting tissue regeneration. Inspired by the immunomodulatory role of spermidine, an injectable double network hydrogel functionalized with spermidine (DN-SPD) is developed, where the first and second networks are formed by dynamic imine bonds and non-dynamic photo-crosslinked bonds respectively. The single network hydrogel before photo-crosslinking exhibits excellent injectability and thus can be printed and photo-crosslinked in situ to form double network hydrogels. DN-SPD hydrogel has demonstrated desirable mechanical properties and tissue adhesion. More importantly, an "operando" comparison of hydrogels loaded with spermidine or diethylenetriamine (DETA), a sham molecule resembling spermidine, has shown similar physical properties, but quite different biological functions. Specifically, the outcomes of 3 sets of in vivo animal experiments demonstrate that DN-SPD hydrogel can not only reduce inflammation caused by implanted exogenous biomaterials and reactive oxygen species but also promote the polarization of macrophages toward regenerative M2 phenotype, in comparison with DN-DETA hydrogel. Moreover, the immunoregulation by spermidine can also translate into faster and more natural healing of both acute wounds and diabetic wounds. Hence, the local administration of spermidine affords a simple but elegant approach to attenuate foreign body reactions induced by exogenous biomaterials to treat chronic refractory wounds.

Boosting sodium-ion battery performance with binary metal-doped Na3V2(PO4)2F3 cathodes.

Na3V2(PO4)2F3 (NVPF), recognized for its Na superionic conductor architecture, emerges as a promising candidate among polyanion-type cathodes for sodium ion batteries (SIBs). However, its adoption in practical applications faces obstacles due to its inherently low electronic conductivity. To address this challenge, we employ a binary co-doped strategy to design Na3.3K0.2V1.5Mg0.5(PO4)2F3 cathode with nitrogen-doped carbon (NC) coating layer. This configuration enhances electronic conductivity and reduces diffusion barriers for sodium ion (Na+). The strategy of incorporating nitrogen-doped carbon coating not only facilitates the formation of a porous structure but also introduces additional defects and active sites. Such modifications accelerate the reaction kinetics and augment electrolyte interaction through an expanded specific surface area, thus streamlining the electrochemical process. Concurrently, strategic heteroatom substitution leads to a more efficient engagement of Na+ in the electrochemical activities, thereby bolstering the cathode's structural integrity. The vanadium fluorophosphate Na3.3K0.2V1.5Mg0.5(PO4)2F3@NC exhibits an electrochemical performance, including a high discharge specific capacity of 124.3 mA h g-1 at 0.1C, a long lifespan of 1000 cycles with a capacity retention of 93.1 % at 10C, and a rate property of 73.2 mA h g-1 at 20C. This research provides a method for preparing binary doped NVPF for energy storage electrochemistry.

Advancing Guideline-Directed Medical Therapy in Heart Failure: Overcoming Challenges and Maximizing Benefits.

The delayed titration of guideline-directed drug therapy (GDMT) is a complex event influenced by multiple factors that often result in poor prognosis for patients with heart failure (HF). Individualized adjustments in GDMT titration may be necessary based on patient characteristics, and every clinician is responsible for promptly initiating GDMT and titrating it appropriately within the patient's tolerance range. This review examines the current challenges in GDMT implementation and scrutinizes titration considerations within distinct subsets of HF patients, with the overarching goal of enhancing the adoption and effectiveness of GDMT. The authors also underscore the significance of establishing a novel management strategy that integrates cardiologists, nurse practitioners, pharmacists, and patients as a unified team that can contribute to the improved promotion and implementation of GDMT.

A high level of uric acid is associated with long-term adverse cardiovascular outcomes in patients who received fractional flow reserve with coronary intermediate stenosis.

BACKGROUND AND AIMS: The role of fractional flow reserve (FFR) in coronary intermediate lesions is widely recommended by guidelines. The effect of uric acid (UA) on cardiovascular events is also well known. However, the relationship between UA and long-term cardiovascular outcomes in patients who received FFR with intermediate lesions remains unknown. METHODS AND RESULTS: We retrospectively included 428 patients who underwent both coronary angiography (CAG) and FFR. Participants were stratified into two groups based on the median UA. The primary endpoint was the composite of major adverse cardiovascular and cerebrovascular events (MACCEs), including repeat revascularization, nonfatal stroke, nonfatal myocardial infarction, and all-cause death. A Cox proportional hazards model was utilized to analyze the association between UA and the prevalence of MACCEs. During a median follow-up of 5.8 years, a higher MACCEs rate occurred in the high UA group compared to the low UA group (16.8% vs. 5.1%, p log-rank<0.01). Elevated UA was independently linked to a higher incidence of MACCEs, whether UA was treated as a categorical or continuous variable (hazard ratio [HR] 2.76, 95% confidence interval [CI] 1.27-6.03 or HR 1.01, 95% CI 1.01-1.02). The restricted cubic spline (RCS) analysis illustrated that the HR for MACCEs increased with increasing UA. CONCLUSION: The present study demonstrates that UA is associated with MACCEs risk and suggests that UA is a reliable predictor of long-term cardiovascular events in coronary intermediate stenosis patients.

Causal association of depression, anxiety, cognitive performance, the brain cortical structure with pulmonary arterial hypertension: A Mendelian randomization study.

BACKGROUND: Patients with pulmonary arterial hypertension (PAH) often present with anxiety, depression and cognitive deterioration. Structural changes in the cerebral cortex in PAH patients have also been reported in observational studies. METHODS: PAH genome-wide association (GWAS) including 162,962 European individuals was used to assess genetically determined PAH. GWAS summary statistics were obtained for cognitive performance, depression, anxiety and alterations in cortical thickness (TH) or surface area (SA) of the brain cortex, respectively. Two-sample Mendelian randomization (MR) was performed. Finally, sensitivity analyses including Cochran's Q test, MR-Egger intercept test, leave-one-out analyses, and funnel plot was performed. RESULTS: PAH had no causal relationship with depression, anxiety, and cognitive performance. At the global level, PAH was not associated with SA or TH of the brain cortex; at the functional regional level, PAH increased TH of insula (P = 0.015), pars triangularis (P = 0.037) and pars opercularis (P = 0.010) without global weighted. After global weighted, PAH increased TH of insula (P = 0.004), pars triangularis (P = 0.032), pars opercularis (P = 0.007) and rostral middle frontal gyrus (P = 0.022) while reducing TH of inferior parietal (P = 0.004), superior parietal (P = 0.031) and lateral occipital gyrus (P = 0.033). No heterogeneity and pleiotropy were detected. LIMITATIONS: The enrolled patients were all European and the causal relationship between PAH and the structure of the cerebral cortex in other populations remains unknown. CONCLUSION: Causal relationship between PAH and the brain cortical structure was implied, thus providing novel insights into the PAH associated neuropsychiatric symptoms.

Pt,P-codoped carbon nitride nanoenzymes for fluorescence and colorimetric dual-mode detection of cholesterol.

Cholesterol is an important lipid compound found in a variety of foods, and its level in human blood is closely related to human health. Therefore, development of rapid and accurate POCT (point-of-care testing) methods for cholesterol detection is crucial for assessing food quality and early diagnosis of diseases, in particular, in a resource-limited environment. In this study, a smartphone-assisted colorimetric biosensor is constructed based on platinum,phosphorus-codoped carbon nitride (PtCNP2) for the rapid detection of cholesterol. Phosphorus-doped carbon nitride is prepared by thermal annealing of urea and NH4PF6, into which platinum is atomically dispersed by thermal refluxing. The obtained PtCNP2 exhibits an excellent peroxidase-like activity under physiological pH, whereby colorless o-phenylenediamine (OPD) is oxidized to colored 2,3-diaminophenazine (DAP) in the presence of hydrogen peroxide (H2O2), which can be produced during the oxidation of cholesterol by cholesterol oxidase. A smartphone-assisted visual sensing system is then constructed based on the color recognition software, and rapid on-site detection of cholesterol is achieved by reading the RGB values. Meanwhile, the generated DAP shows an apparent fluorescence signal and can realize highly sensitive detection of cholesterol by the change of the fluorescence signal intensity. Such a cholesterol sensor exhibits a wide linear detection range of 0.5-600 µg mL-1 and a low detection limit of 59 ng mL-1. The practicality of the sensor is successfully demonstrated in the rapid detection of cholesterol in serum and food.

Causal relationship between particulate matter and COVID-19 risk: A mendelian randomization study.

Background: Observational studies have linked exposure to fine (PM2.5) and coarse (PM10) particulate matter air pollution with adverse COVID-19 outcomes, including higher incidence and mortality. However, some studies questioned the effect of air pollution on COVID-19 susceptibility, raising questions about the causal nature of these associations. To address this, a less biased method like Mendelian randomization (MR) is utilized, which employs genetic variants as instrumental variables to infer causal relationships in observational data. Method: We performed two-sample MR analysis using public genome-wide association studies data. Instrumental variables correlated with PM2.5 concentration, PM2.5 absorbance, PM2.5-10 concentration and PM10 concentration were identified. The inverse variance weighted (IVW), robust adjusted profile score (RAPS) and generalized summary data-based Mendelian randomization (GSMR) methods were used for analysis. Results: IVW MR analysis showed PM2.5 concentration [odd ratio (OR) = 3.29, 95% confidence interval (CI) 1.48-7.35, P-value = 0.0036], PM2.5 absorbance (OR = 5.62, 95%CI 1.98-15.94, P-value = 0.0012), and PM10 concentration (OR = 3.74, 95%CI 1.52-9.20, P-value = 0.0041) increased the risk of COVID-19 severity after Bonferroni correction. Further validation confirmed PM2.5 absorbance was associated with heightened COVID-19 severity (OR = 6.05, 95%CI 1.99-18.38, P-value = 0.0015 for RAPS method; OR = 4.91, 95%CI 1.65-14.59, P-value = 0.0042 for GSMR method) and hospitalization (OR = 3.15, 95%CI 1.54-6.47, P-value = 0.0018 for RAPS method). No causal links were observed between particulate matter exposure and COVID-19 susceptibility. Conclusions: Our study established a causal relationship between smaller particle pollution, specifically PM2.5, and increased risk of COVID-19 severity and hospitalization. These findings highlight the importance of improving air quality to mitigate respiratory disease progression.

Establishment of RPA-Cas12a-Based Fluorescence Assay for Rapid Detection of Feline Parvovirus.

Feline parvovirus (FPV) is highly infectious for cats and other Felidae and often causes severe damage to young kittens. In this study, we incorporated recombinase polymerase amplification (RPA) and Cas12a-mediated detection and developed an RPA-Cas12a-based real-time or end-point fluorescence detection method to identify the NS1 gene of FPV. The total time of RPA-Cas12a-based fluorescence assay is approximately 25 min. The assay presented a limit of detection (LOD) of 1 copies/µl (25 copies/per reaction), with no cross-reactivity with several feline pathogens. The clinical performance of the assay was examined using total genomic DNA purified from 60 clinical specimens and then compared to results obtained with qPCR detection of FPV with 93.3% positive predictive agreement and 100% negative predictive agreement. Together, the rapid reaction, cost-effectiveness, and high sensitivity make the RPA-Cas12a-based fluorescence assay a fascinating diagnostic tool that will help minimize infection spread through instant detection of FPV.

Water-dispersible donor-acceptor-donor π-conjugated bolaamphiphiles enabling a humidity-responsive luminescence color change.

Novel water-dispersible donor-acceptor-donor π-conjugated bolaamphiphiles, having dibenzophenazine as the acceptor and heteroatom-bridged amphiphilic diarylamines as the donors, have been developed. The materials displayed a distinct photoluminescence color change in response to humidity in a poly(vinylalcohol) matrix.

Correction: Water-dispersible donor-acceptor-donor π-conjugated bolaamphiphiles enabling a humidity-responsive luminescence color change.

Correction for 'Water-dispersible donor-acceptor-donor π-conjugated bolaamphiphiles enabling a humidity-responsive luminescence color change' by Tomoya Enjou et al., Chem. Commun., 2024, https://doi.org/10.1039/d3cc05749f.

Investigation of clinical significance of ST-segment depression during paroxysmal supraventricular tachycardia.

INTRODUCTION: There are great differences in ST-segment depression during PSVT episodes. The aim of this study is to investigate the clinical significance of ST segment depression during PSVT. METHODS: The study enrolled 333 consecutive patients who were diagnosed with PSVT by electrophysiological test from Jan 1, 2021 to July 31, 2022. The range, magnitude and morphology of ST-segment depression were described. The correlation between ST-segment depression and symptoms of chest tightness, chest pain or hypotension, the correlation between ST-segment depression and coronary stenosis, and the possible influencing factors were analyzed. In addition, the diagnostic efficacy of ST-segment depression for AVRT was determined. RESULTS: ST-segment depression was present in 85% of patients, in 70% of which the depression range was more than six leads. The magnitude of the depression was more significant in precordial leads (P < 0.001). ST-segment depression of >1 mm in limb leads and precordial leads was found in 36.0% and 49.8% of the patients, respectively, while >3 mm was found in 2.4% and 9.6%, respectively. The morphology of ST-segment depression in limb leads was different from that in precordial leads (P < 0.001). Downsloping ST-segment depression was more common in limb leads (limb vs. precordial: 40.5% vs. 12.6%), whereas upsloping depression was more common in precordial leads (limb vs. precordial: 3.0% vs. 23.1%). Correlation analysis showed that ST-segment depression was not correlated with symptoms of chest tightness and pain, nor was it correlated with coronary artery stenosis. The most important influencing factor is the type of PSVT, especially affecting the morphology of depression in limb leads (OR = 10.27 [5.93-17.79], P < 0.001). The sensitivity and specificity of downsloping ST-segment depression in limb leads for diagnosis of AVRT were 75.5% and 76.7%. CONCLUSION: ST-segment depression is a common ECG change during PSVT episodes, and it's not associated with severe coronary stenosis. The type of PSVT has a significant effect on the manifestation of ST-segment depression. The downslope morphology of ST-segment depression in limb leads is helpful in differentiating AVRT from AVNRT.

Overcoming barriers for left atrial appendage thrombus: a systematic review of left atrial appendage closure.

BACKGROUND: Approximately 90% of intracardial thrombi originate from the left atrial appendage in non-valvular atrial fibrillation patients. Even with anticoagulant therapy, left atrial appendage thrombus (LAAT) still occurs in 8% of patients. While left atrial appendage closure (LAAC) could be a promising alternative, the current consensus considers LAAT a contraindication to LAAC. However, the feasibility and safety of LAAC in patients with LAAT have yet to be determined. METHODS: This systematic review synthesizes published data to explore the feasibility and safety of LAAC for patients with LAAT. RESULTS: This study included a total of 136 patients with LAATs who underwent successful LAAC. The Amulet Amplatzer device was the most frequently utilized device (48.5%). Among these patients, 77 (56.6%) had absolute contraindications to anticoagulation therapy. Cerebral protection devices were utilized by 47 patients (34.6%). Transesophageal echocardiography (TEE) is the primary imaging technique used during the procedure. Warfarin and novel oral anticoagulants were the main anticoagulant medications used prior to the procedure, while dual antiplatelet therapy was primarily used post-procedure. During a mean follow-up period of 13.2 ± 11.5 months, there was 1 case of fatality, 1 case of stroke, 3 major bleeding events, 3 instances of device-related thrombus, and 8 cases of peri-device leakage. CONCLUSIONS: This review highlights the preliminary effectiveness and safety of the LAAC procedure in patients with persistent LAAT. Future large-scale RCTs with varied LAAT characteristics and LAAC device types are essential for evidence-based decision-making in clinical practice.

Layer-by-layer growth of Cu3(HHTP)2 films on Cu(OH)2 nanowire arrays for high performance ascorbic acid sensing.

Growing three-dimensional (3D) metal organic frameworks (MOFs) via heterogeneous epitaxial growth on metal hydroxide arrays are effective for constructing electrochemical sensor. However, the growth of MOFs is difficult to control, resulting in thick and irregular morphologies and even damage the metal hydroxide template. In this work, Cu3(HHTP)2 (HHTP = 2, 3, 6, 7, 10, 11-hexahydroxytriphenylene) films with controllable thickness and morphology were successfully prepared on Cu(OH)2 nanowire arrays (NWAs) through layer-by-layer (LBL) growth method. We have discovered that the LBL cycle and the reaction solvent composition are crucial for growing homogenous MOF thin films. The Cu3(HHTP)2 based ascorbic acid (AA) sensor, fabricated in ethanol within 10 LBL cycles, generated an ultrahigh sensitivity of 821.64 µA mM-1 cm-2 in the range of 6-981.41 µM, a low detection limit of 60 nM as well as the great selectivity, stability and reproducibility. Moreover, the relative deviation for AA detection in two fruit juices were 3.22 % and 3.71 %, and the test result for human sweat fall within the normal AA concentration range, verifying the feasibility of as-prepared sensor for practical application.

Amino acid profile alteration in age-related atrial fibrillation.

BACKGROUND: Amino acids (AAs) are one of the primary metabolic substrates for cardiac work. The correlation between AAs and both atrial fibrillation (AF) and aging has been documented. However, the relationship between AAs and age-related AF remains unclear. METHODS: Initially, the plasma AA levels of persistent AF patients and control subjects were assessed, and the correlations between AA levels, age, and other clinical indicators were explored. Subsequently, the age-related AF mouse model was constructed and the untargeted myocardial metabolomics was conducted to detect the level of AAs and related metabolites. Additionally, the gut microbiota composition associated with age-related AF was detected by a 16S rDNA amplicon sequencing analysis on mouse fecal samples. RESULTS: Higher circulation levels of lysine (Student's t-test, P = 0.001), tyrosine (P = 0.002), glutamic acid (P = 0.008), methionine (P = 0.008), and isoleucine (P = 0.014), while a lower level of glycine (P = 0.003) were observed in persistent AF patients. The feature AAs identified by machine learning algorithms were glutamic acid and methionine. The association between AAs and age differs between AF and control subjects. Distinct patterns of AA metabolic profiles were observed in the myocardial metabolites of aged AF mice. Aged AF mice had lower levels of Betaine, L-histidine, L-alanine, L-arginine, L-Pyroglutamic acid, and L-Citrulline compared with adult AF mice. Aged AF mice also presented a different gut microbiota pattern, and its functional prediction analysis showed AA metabolism alteration. CONCLUSION: This study provided a comprehensive network of AA disturbances in age-related AF from multiple dimensions, including plasma, myocardium, and gut microbiota. Disturbances of AAs may serve as AF biomarkers, and restoring their homeostasis may have potential benefits for the management of age-related AF.

Grinding-Induced Water Solubility Exhibited by Mechanochromic Luminescent Supramolecular Fibers.

Most mechanochromic luminescent compounds are crystalline and highly hydrophobic; however, mechanochromic luminescent molecular assemblies comprising amphiphilic molecules have rarely been explored. This study investigated mechanochromic luminescent supramolecular fibers composed of dumbbell-shaped 9,10-bis(phenylethynyl)anthracene-based amphiphiles without any tetraethylene glycol (TEG) substituents or with two TEG substituents. Both amphiphiles formed water-insoluble supramolecular fibers via linear hydrogen bond formation. Both compounds acquired water solubility when solid samples composed of supramolecular fibers are ground. Grinding induces the conversion of 1D supramolecular fibers into micellar assemblies where fluorophores can form excimers, thereby resulting in a large redshift in the fluorescence spectra. Excimer emission from the ground amphiphile without TEG chains is retained after dissolution in water. The micelles are stable in water because hydrophilic dendrons surround the hydrophobic luminophores. By contrast, when water is added to a ground amphiphile having TEG substituents, fragmented supramolecular fibers with the same molecular arrangement as the initial supramolecular fibers are observed, because fragmented fibers are thermodynamically preferable to micelles as the hydrophobic arrays of fluorophores are covered with hydrophilic TEG chains. This leads to the recovery of the initial fluorescent properties for the latter amphiphile. These supramolecular fibers can be used as practical mechanosensors to detect forces at the mesoscale.