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1.
Adv Sci (Weinh) ; : e2307224, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38946607

RESUMO

Targeting NLRP3 inflammasome has been recognized as a promising therapeutic strategy for the treatment of numerous common diseases. UK5099, a long-established inhibitor of mitochondrial pyruvate carrier (MPC), is previously found to inhibit macrophage inflammatory responses independent of MPC expression. However, the mechanisms by which UK5099 inhibit inflammatory responses remain unclear. Here, it is shown that UK5099 is a potent inhibitor of the NLRP3 inflammasome in both mouse and human primary macrophages. UK5099 selectively suppresses the activation of the NLRP3 but not the NLRC4 or AIM2 inflammasomes. Of note, UK5099 retains activities on NLRP3 in macrophages devoid of MPC expression, indicating this inhibitory effect is MPC-independent. Mechanistically, UK5099 abrogates mitochondria-NLRP3 interaction and in turn inhibits the assembly of the NLRP3 inflammasome. Further, a single dose of UK5099 persistently reduces IL-1ß production in an endotoxemia mouse model. Importantly, structure modification reveals that the inhibitory activities of UK5099 on NLRP3 are unrelated to the existence of the activated double bond within the UK5099 molecule. Thus, this study uncovers a previously unknown molecular target for UK5099, which not only offers a new candidate for the treatment of NLRP3-driven diseases but also confounds its use as an MPC inhibitor in immunometabolism studies.

2.
Medicine (Baltimore) ; 103(26): e38583, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38941365

RESUMO

The aspartate to alanine transaminase (AST/ALT) ratio indicates oxidative stress and inflammatory reactions related to the occurrence of diabetic retinopathy (DR). Currently, there are no reports on the correlation between AST/ALT ratio and DR. Hence, this study aimed to explore the relationship between AST/ALT ratio and DR. This cross-sectional study utilized data from the Metabolic Management Center of the First People's Hospital in City. In total, 1365 patients with type 2 diabetes mellitus (T2DM) participated in the study, including 244 patients with DR and 1121 patients without DR. We collected the results of fundus photography, liver function, and other research data and grouped them according to tertiles of AST/ALT ratios. DR prevalence was the highest in the group with the highest AST/ALT ratio (22.12%, P = .004). Both univariate (OR = 2.25, 95% CI: 1.51-3.34, P < .001) and multivariable logistic regression analyses (adjusted for confounding factors) showed that the risk of DR increased by 36% when the AST/ALT ratio increased by 1 standard deviation (SD) (OR = 1.36, 95% CI: 1.16-1.59, P < .001), and 29.3% was mediated by the duration of diabetes. A sensitivity analysis confirmed the stability of the results. This study showed that an increase in AST/ALT ratio is an independent risk factor for DR.


Assuntos
Alanina Transaminase , Aspartato Aminotransferases , Diabetes Mellitus Tipo 2 , Retinopatia Diabética , Humanos , Retinopatia Diabética/epidemiologia , Retinopatia Diabética/sangue , Retinopatia Diabética/etiologia , Estudos Transversais , Masculino , Feminino , Pessoa de Meia-Idade , Fatores de Risco , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Idoso , Prevalência , Biomarcadores/sangue
3.
J Control Release ; 371: 313-323, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823585

RESUMO

Poly(ethylene glycol) (PEG) is widely utilized as a hydrophilic coating to extend the circulation time and improve the tumor accumulation of polymeric micelles. Nonetheless, PEGylated micelles often activate complement proteins, leading to accelerated blood clearance and negatively impacting drug efficacy and safety. Here, we have crafted amphiphilic block copolymers that merge hydrophilic sulfoxide-containing polymers (psulfoxides) with the hydrophobic drug 7-ethyl-10-hydroxylcamptothecin (SN38) into drug-conjugate micelles. Our findings show that the specific variant, PMSEA-PSN38 micelles, remarkably reduce protein fouling, prolong blood circulation, and improve intratumoral accumulation, culminating in significantly increased anti-cancer efficacy compared with PEG-PSN38 counterpart. Additionally, PMSEA-PSN38 micelles effectively inhibit complement activation, mitigate leukocyte uptake, and attenuate hyperactivation of inflammatory cells, diminishing their ability to stimulate tumor metastasis and cause inflammation. As a result, PMSEA-PSN38 micelles show exceptional promise in the realm of anti-metastasis and significantly abate SN38-induced intestinal toxicity. This study underscores the promising role of psulfoxides as viable PEG substitutes in the design of polymeric micelles for efficacious anti-cancer drug delivery.


Assuntos
Irinotecano , Micelas , Pró-Fármacos , Animais , Pró-Fármacos/administração & dosagem , Pró-Fármacos/química , Pró-Fármacos/farmacologia , Humanos , Irinotecano/administração & dosagem , Irinotecano/farmacocinética , Linhagem Celular Tumoral , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/farmacocinética , Polímeros/química , Feminino , Camundongos Endogâmicos BALB C , Polietilenoglicóis/química , Sulfóxidos , Camundongos , Intestinos/efeitos dos fármacos , Camundongos Nus , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Portadores de Fármacos/química
4.
Microb Pathog ; 193: 106760, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38914348

RESUMO

Outer membrane protein A (OmpA), a major component of outer membrane proteins in gram-negative bacteria, is considered to be an important virulence factor in various pathogenic bacteria, but its underlying mechanisms involved in pathogenic process of Edwardsiella tarda has not yet been fully elucidated. E. tarda is an important facultative intracellular pathogen with a broad host range. This bacterium could survive and replicate in macrophages as an escape mechanism from the host defense. To address the functions of OmpA and its potential roles in the pathogenesis of E. tarda, ΔompA mutant strain and ΔompA-C complementary strain were constructed by the allelic exchange method in this study. Here, we demonstrate that the abilities of motility, biofilm formation and adherence to RAW264.7 cells of ΔompA were significantly impaired, although there was no difference in growth between wild-type (WT) strain and ΔompA. Moreover, inactivation of ompA rendered E. tarda more sensitive to oxidative, heat shock and osmotic stress, which simulate the in vivo conditions that E. tarda encounters within the intramacrophage environment. Consist with this observation, ΔompA was also found to be markedly attenuated for growth within macrophages. In addition, compared with the WT strain, ΔompA activated macrophages to release more inflammatory mediators, including tumor necrosis factor alpha (TNF-α), reactive oxygen species (ROS) and nitric oxide (NO). However, flow cytometry analysis revealed that ΔompA induced less apoptosis of RAW264.7 cells as compared with WT strain, characterized by decreased Annexin V binding and the activation of caspase-3. Overall, our findings suggest an importance of OmpA to E. tarda and provide the first comprehensive insight into its functions and potential roles in the pathogenesis of E. tarda, including its effect on interaction with macrophages.

5.
Sci Total Environ ; 946: 174222, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38945230

RESUMO

The presence of antibiotic resistance genes (ARGs), disinfectant resistance genes (DRGs), and pathogens in animal food processing environments (FAPE) poses a significant risk to human health. However, knowledge of the contamination and risk profiles of a typical commercial pig slaughterhouse with periodic disinfectant applications is limited. By creating the overall metagenomics-based behavior and risk profiles of ARGs, DRGs, and microbiomes in a nine-section pig slaughterhouse, an important FAPE in China. A total of 454 ARGs and 84 DRGs were detected in the slaughterhouse with resistance genes for aminoglycosides and quaternary ammonium compounds, respectively. The entire slaughtering chain is a hotspot for pathogens, including 83 human pathogenic bacteria (HPB), with 47 core HPB. In addition, 68 high-risk ARGs were significantly correlated with 55 HPB, 30 of which were recognized as potential bacteria co-resistant to antibiotics and disinfectants, confirm a three-fold risk of ARGs, DRGs, and pathogens prevailing throughout the chain. Pre-slaughter pig house (PSPH) was the major risk source for ARGs, DRGs, and HPB. Moreover, 75 Escherichia coli and 47 Proteus mirabilis isolates showed sensitivity to potassium monopersulfate and sodium hypochlorite, suggesting that slaughterhouses should use such related disinfectants. By using whole genome multi-locus sequence typing and single nucleotide polymorphism analyses, genetically closely related bacteria were identified across distinct slaughter sections, suggesting bacterial transmission across the slaughter chain. Overall, this study underscores the critical role of the PSPH section as a major source of HPB, ARGs, and DRGs contamination in commercial pig slaughterhouses. Moreover, it highlights the importance of addressing clonal transmission and cross-contamination of antibiotic- and disinfectant-resistant bacteria within and between slaughter sections. These issues are primarily attributed to the microbial load carried by animals before slaughter, carcass handling, and content exposure during visceral treatment. Our findings provide valuable insights for One Health-oriented slaughterhouse management practices.

6.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 36(5): 532-537, 2024 May.
Artigo em Chinês | MEDLINE | ID: mdl-38845502

RESUMO

OBJECTIVE: To investigate the clinical efficacy of continuous veno-venous hemodia-filtration (CVVHDF) combined with hemoperfusion (HP) HA380 in the treatment of heat stroke patients with multiple organ dysfunction syndrome (MODS). METHODS: A retrospective and observational study was conducted. A total of 15 patients with heat stroke combined with MODS who were admitted to the department of intensive care unit (ICU) of Suizhou Central Hospital/Hubei University of Medicine from July to September 2022 were selected as the study objects. All 15 patients were treated with CVVHDF combined with HA380 based on the comprehensive management strategy for severe illness. Organ function indicators [including total bilirubin (TBil), aspartate aminotransferase (AST), creatine kinase (CK), lactate dehydrogenase (LDH), creatinine (Cr), cardiac troponin T (cTnT), myoglobin (Myo), MB isoenzyme of creatine kinase (CK-MB), sequential organ failure assessment (SOFA)] and inflammatory indicators [including white blood cell count (WBC), neutrophil count (NEU), C-reactive protein (CRP), procalcitonin (PCT), and interleukin-6 (IL-6)] were collected. The improvements of the above indexes at admission, after the first HP, after the second HP, after the third HP, and on the 5th day of treatment were compared. Combined with the clinical outcome of patients, the comprehensive efficacy of CVVHDF combined with HA380 in the treatment of severe heat radiation disease was evaluated. RESULTS: There were 10 males and 5 females among the 15 patients. The average age was (64.5±11.5) years old. There were 6 cases of classical heat stroke and 9 cases of exertional heat stroke. Glasgow coma scale (GCS) was 3-8 at admission; SOFA score was 9-17 within 12 hours after admission; acute physiology and chronic health evaluation II (APACHE II) was 25-45 within 24 hours after admission. After treatment, the IL-6 level and SOFA score gradually decreased, and there were significant differences in the decrease after the second HP compared to admission [IL-6 (ng/L): 48.37 (15.36, 113.03) vs. 221.90 (85.87, 425.90), SOFA: 8.3±3.3 vs. 11.1±2.4, both P < 0.05]. The PCT level reached its peak after the first HP [12.51 (6.07, 41.65) µg/L], and then gradually decreased, and the difference was statistically significant after the third HP [1.26 (0.82, 5.40) µg/L, P < 0.05]. Compared those at admission, Cr level significantly improved after the first HP (µmol/L: 66.94±25.57 vs. 110.80±31.13, P < 0.01), Myo significantly decreased after the second HP [µg/L: 490.90 (164.98, 768.05) vs. 3 000.00 (293.00, 3 000.00), P < 0.05], After the third HP, the CK level also showed significant improvement [U/L: 476.0 (413.0, 922.0) vs. 2 107.0 (729.0, 2 449.0), P < 0.05]. After CVVHDF combined with 3 times HP treatment, the patient's inflammatory response was gradually controlled and organ function gradually recovered. On the 5th day of the disease course, WBC, PCT and IL-6 levels were significantly improved compared to admission, and AST, CK, LDH, Cr, Myo, CK-MB, and SOFA score were significantly corrected compared with those on admission. The 24-hour survival rate of 15 patients was 86.67%, and the 24-hour, 7-day and 28-day survival rates were both as high as 73.33%. The average mechanical ventilation time of 11 surviving patients was (101.8±22.0) hours, the average continuous renal replacement therapy (CRRT) time was (58.8±11.0) hours, the average length of ICU stay was (6.3±1.0) days, and the average total hospitalization was (14.6±5.2) days. CONCLUSIONS: CVVHDF combined with HP HA380 in the treatment of heat stroke patients with MODS can effectively improve organ function and alleviate the inflammatory storm, which is an effective means to improve the rescue rate and reduce the mortality of severe heat stroke patients.


Assuntos
Golpe de Calor , Hemoperfusão , Insuficiência de Múltiplos Órgãos , Humanos , Insuficiência de Múltiplos Órgãos/terapia , Insuficiência de Múltiplos Órgãos/etiologia , Estudos Retrospectivos , Hemoperfusão/métodos , Golpe de Calor/terapia , Interleucina-6/sangue , Unidades de Terapia Intensiva , Terapia de Substituição Renal Contínua/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Resultado do Tratamento
7.
Front Mol Biosci ; 11: 1282100, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38872917

RESUMO

Background: This paper aims to analyse the active components of Semen cuscutae (SC) by network pharmacology and screen the most stable compounds with tumour necrosis factor-alpha (TNF-α) by molecular docking to explore the mechanisms of SC treatment of recurrent spontaneous abortion (RSA) and provide a theoretical basis for drug development. Methods: The active compounds of SC and the potential inflammatory targets of RSA were obtained from the Traditional Chinese Medicine Systems Pharmacology database and GeneCards, respectively. The RSA-SC target gene interaction network was obtained and visualized using the STRING database and Cytoscape software. GO and KEGG pathway enrichment analyses were obtained from DAVID to further explore the RSA mechanism and therapeutic effects of SC. Interactions between TNF-α and drugs were analysed by molecular docking. Treatment of human trophoblast cells with sesamin and TNF-α was carried out to detect their proliferative and apoptotic abilities, and WB assay was carried out to detect EGFR, PTGS2, and CASP3 protein expression. Results: Ten compounds and 128 target genes were screened from SC, of which 79 overlapped with RSA target inflammatory genes, which were considered potential therapeutic targets. Network pharmacological analysis showed that sesamin, matrine, matrol, and other SC compounds had a good correlation with the inflammatory target genes of RSA. Related genes included PGR, PTGS1, PTGS2, TGFB1, and CHRNA7. Several signalling pathways are involved in the pathogenesis of RSA, such as the TNF-α signalling pathway, HIF-1 signalling pathway, oestrogen signalling pathway, proteoglycans in cancer cells, and FoxO signalling pathway. Molecular docking results suggested that sesamin was the most suitable natural tumour necrosis factor inhibitor (TNFi). Sesamin can promote proliferation and inhibit apoptosis in human trophoblasts by downregulating EGFR and CASP3 expression and upregulating PTGS2 expression. Conclusion: Our findings play an important role and basis for further research into the molecular mechanism of SC treatment of RSA and drug development of TNFi.

8.
Adv Sci (Weinh) ; : e2401818, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38885350

RESUMO

Glycosylation is the most common post-translational modification of proteins and regulates a myriad of fundamental biological processes under normal, and pathological conditions. Altered protein glycosylation is linked to malignant transformation, showing distinct glycopatterns that are associated with cancer initiation and progression by regulating tumor proliferation, invasion, metastasis, and therapeutic resistance. The glycopatterns of small extracellular vesicles (sEVs) released by cancer cells are promising candidates for cancer monitoring since they exhibit glycopatterns similar to their cell-of-origin. However, the clinical application of sEV glycans is challenging due to the limitations of current analytical technologies in tracking the trace amounts of sEVs specifically derived from tumors in circulation. Herein, a sEV GLYcan PHenotype (EV-GLYPH) assay that utilizes a microfluidic platform integrated with surface-enhanced Raman scattering for multiplex profiling of sEV glycans in non-small cell lung cancer is clinically validated. For the first time, the EV-GLYPH assay effectively identifies distinct sEV glycan signatures between non-transformed and malignantly transformed lung cells. In a clinical study evaluated on 40 patients, the EV-GLYPH assay successfully differentiates patients with early-stage malignant lung nodules from benign lung nodules. These results reveal the potential to profile sEV glycans for noninvasive diagnostics and prognostics, opening up promising avenues for clinical applications and understanding the role of sEV glycosylation in lung cancer.

9.
Diabetol Metab Syndr ; 16(1): 123, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38840161

RESUMO

BACKGROUND: Few studies have compared the correlation between visceral fat area (VFA) and abdominal subcutaneous fat area (SFA) with arterial stiffness (AS) in patients with type 2 diabetes (T2D). In addition, there is currently controversy regarding the correlation between VFA and SFA with AS. We aimed to investigate the relationship between VFA and SFA with AS in patients with T2D. METHODS: In this cross-sectional study, 1475 Chinese T2D patients with an average age of 52.32 ± 10.96 years were included. VFA and SFA were determined by a dual bioelectrical impedance analyzer, and AS was determined by measurement of brachial-ankle pulse wave conduction velocity (baPWV). Atherosclerosis was deemed present in study participants with baPWV values higher than 75th percentile (1781 cm/s). Independent correlations of logVFA and logSFA with AS were assessed using multiple linear regression and multivariate logistic regression. RESULTS: The baPWV was linked with VFA, waist circumference, and women's SFA in a general linear correlation study (P < 0.05), but not with body mass index (P = 0.3783) or men's SFA (P = 0.1899). In both men and women, VFA and SFA were positively correlated with AS, according to the generalized additive model (GAM). After fully adjusting for confounders, multiple linear regression analyses showed that for every 1-unit increase in logVFA, the beta coefficient of baPWV increased by 63.1 cm/s (95% CI: 18.4, 107.8) (P < 0.05). logSFA did not correlate significantly with baPWV (P = 0.125). In the multiple logistic regression analysis, the odds ratio (OR) of elevated baPWV was 1.8 (95% CI: 1.1, 3.1) (P = 0.019) per 1-unit increase in logVFA. logSFA did not correlate significantly with AS (P = 0.091). In the subgroup analysis, the correlation between logVFA and baPWV did not interact across subgroups (P-interaction > 0.05). CONCLUSIONS: Compared with SFA, VFA had a stronger independent positive correlation with AS in Chinese T2D patients. Patients with T2D should pay more attention to monitoring VFA and lowering it to minimize cardiovascular events.

11.
Curr Med Sci ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38926331

RESUMO

OBJECTIVE: Bladder outlet obstruction (BOO) results in significant fibrosis in the chronic stage and elevated bladder pressure. Piezo1 is a type of mechanosensitive (MS) channel that directly responds to mechanical stimuli. To identify new targets for intervention in the treatment of BOO-induced fibrosis, this study investigated the impact of high hydrostatic pressure (HHP) on Piezo1 activity and the progression of bladder fibrosis. METHODS: Immunofluorescence staining was conducted to assess the protein abundance of Piezo1 in fibroblasts from obstructed rat bladders. Bladder fibroblasts were cultured under normal atmospheric conditions (0 cmH2O) or exposed to HHP (50 cmH2O or 100 cmH2O). Agonists or inhibitors of Piezo1, YAP1, and ROCK1 were used to determine the underlying mechanism. RESULTS: The Piezo1 protein levels in fibroblasts from the obstructed bladder exhibited an elevation compared to the control group. HHP significantly promoted the expression of various pro-fibrotic factors and induced proliferation of fibroblasts. Additionally, the protein expression levels of Piezo1, YAP1, ROCK1 were elevated, and calcium influx was increased as the pressure increased. These effects were attenuated by the Piezo1 inhibitor Dooku1. The Piezo1 activator Yoda1 induced the expression of pro-fibrotic factors and the proliferation of fibroblasts, and elevated the protein levels of YAP1 and ROCK1 under normal atmospheric conditions in vitro. However, these effects could be partially inhibited by YAP1 or ROCK inhibitors. CONCLUSION: The study suggests that HHP may exacerbate bladder fibrosis through activating Piezo1.

12.
Chem Commun (Camb) ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38938073

RESUMO

Visible light-induced, transition metal-free oxidative dehydroxylation and C-H amidation of α-hydroxy ketones involving Ritter-type amidation has been developed, leading to the selective synthesis of α,α-diamido- and α-monoamido ketones with tunable selectivity as well as broad substrate tolerance.

13.
Cancer Cell ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38942025

RESUMO

Global investigation of medulloblastoma has been hindered by the widespread inaccessibility of molecular subgroup testing and paucity of data. To bridge this gap, we established an international molecularly characterized database encompassing 934 medulloblastoma patients from thirteen centers across China and the United States. We demonstrate how image-based machine learning strategies have the potential to create an alternative pathway for non-invasive, presurgical, and low-cost molecular subgroup prediction in the clinical management of medulloblastoma. Our robust validation strategies-including cross-validation, external validation, and consecutive validation-demonstrate the model's efficacy as a generalizable molecular diagnosis classifier. The detailed analysis of MRI characteristics replenishes the understanding of medulloblastoma through a nuanced radiographic lens. Additionally, comparisons between East Asia and North America subsets highlight critical management implications. We made this comprehensive dataset, which includes MRI signatures, clinicopathological features, treatment variables, and survival data, publicly available to advance global medulloblastoma research.

14.
Plants (Basel) ; 13(12)2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38931138

RESUMO

Cadmium (Cd), as the most prevalent heavy metal contaminant poses serious risks to plants, humans, and the environment. The ubiquity of this toxic metal is continuously increasing due to the rapid discharge of industrial and mining effluents and the excessive use of chemical fertilizers. Nanoparticles (NPs) have emerged as a novel strategy to alleviate Cd toxicity. Zinc oxide nanoparticles (ZnO-NPs) have become the most important NPs used to mitigate the toxicity of abiotic stresses and improve crop productivity. The plants quickly absorb Cd, which subsequently disrupts plant physiological and biochemical processes and increases the production of reactive oxygen species (ROS), which causes the oxidation of cellular structures and significant growth losses. Besides this, Cd toxicity also disrupts leaf osmotic pressure, nutrient uptake, membrane stability, chlorophyll synthesis, and enzyme activities, leading to a serious reduction in growth and biomass productivity. Though plants possess an excellent defense mechanism to counteract Cd toxicity, this is not enough to counter higher concentrations of Cd toxicity. Applying Zn-NPs has proven to have significant potential in mitigating the toxic effects of Cd. ZnO-NPs improve chlorophyll synthesis, photosynthetic efficiency, membrane stability, nutrient uptake, and gene expression, which can help to counter toxic effects of Cd stress. Additionally, ZnO-NPs also help to reduce Cd absorption and accumulation in plants, and the complex relationship between ZnO-NPs, osmolytes, hormones, and secondary metabolites plays an important role in Cd tolerance. Thus, this review concentrates on exploring the diverse mechanisms by which ZnO nanoparticles can alleviate Cd toxicity in plants. In the end, this review has identified various research gaps that need addressing to ensure the promising future of ZnO-NPs in mitigating Cd toxicity. The findings of this review contribute to gaining a deeper understanding of the role of ZnO-NPs in combating Cd toxicity to promote safer and sustainable crop production by remediating Cd-polluted soils. This also allows for the development of eco-friendly approaches to remediate Cd-polluted soils to improve soil fertility and environmental quality.

16.
J Am Chem Soc ; 146(22): 15167-15175, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38717376

RESUMO

As one of the potential catalysts, disordered solid solution alloys can offer a wealth of catalytic sites. However, accurately evaluating their activity localization structure and overall activity from each individual site remains a formidable challenge. Herein, an approach based on density functional theory and machine learning was used to obtain a large number of sites of the Pt-Ru alloy as the model multisite catalyst for the hydrogen evolution reaction. Subsequently, a series of statistical approaches were employed to unveil the relationship between the geometric structure and overall activity. Based on the radial frequency distribution of metal elements and the distribution of ΔGH, we have identified the surface and subsurface sites occupied by Pt and Ru, respectively, as the most active sites. Particularly, the concept of equivalent site ratio predicts that the overall activity is highest when the Ru content is 20-30%. Furthermore, a series of Pt-Ru alloys were synthesized to validate the proposed theory. This provides crucial insights into understanding the origin of catalytic activity in alloys and thus will better guide the rational development of targeted multisite catalysts.

17.
Org Lett ; 26(22): 4678-4683, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38787784

RESUMO

The radical 1,4-functionalizations of 1,3-enynes have emerged as a powerful strategy for the synthesis of multisubstituted allenes. However, the phosphorus-centered radical-initiated transformations remain largely elusive. Herein, visible-light photoredox catalytic regioselective radical hydrophosphinylation of 1,3-enynes with diaryl phosphine oxides as phosphinoyl radical precursors has been realized. This protocol features mild conditions, a wide substrate scope, and good functional group tolerance, producing a diverse range of phosphinoyl-substituted allenes in moderate to good yields with high atom economy. Detailed mechanistic experiments revealed a radical-polar crossover process in the reaction.

18.
Chemosphere ; 359: 142251, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38710413

RESUMO

BACKGROUND: The individual and combined effects of PM2.5 constituents on cardiometabolic risk factors are sparsely investigated. Besides, the key cardiometabolic risk factor that PM2.5 constituents targeted and the biological mechanisms remain unclear. METHOD: A multistage, stratified cluster sampling survey was conducted in two typically air-polluted Chinese cities. The PM2.5 and its constituents including sulfate, nitrate, ammonium, organic matter, and black carbon were predicted using a machine learning model. Twenty biomarkers in three category were simultaneously adopted as cardiometabolic risk factors. We explored the individual and mixture association of long-term PM2.5 constituents with these markers using generalized additive model and quantile-based g-computation, respectively. To minimize potential confounding effects, we accounted for covariates including demographic, lifestyle, meteorological, temporal trends, and disease-related information. We further used ROC curve and mediation analysis to identify the key subclinical indicators and explore whether inflammatory mediators mediate such association, respectively. RESULT: PM2.5 constituents was positively correlated with HOMA-B, TC, TG, LDL-C and LCI, and negatively correlated with PP and RC. Further, PM2.5 constituent mixture was positive associated with DBP, MAP, HbA1c, HOMA-B, AC, CRI-1 and CRI-2, and negative associated with PP and HDL-C. The ROC analysis further reveals that multiple cardiometabolic risk factors can collectively discriminate exposure to PM2.5 constituents (AUC>0.9), among which PP and CRI-2 as individual indicators exhibit better identifiable performance for nitrate and ammonium (AUC>0.75). We also found that multiple blood lipid indicators may be affected by PM2.5 and its constituents, possibly mediated through complement C3 or hsCRP. CONCLUSION: Our study suggested associations of individual and combined PM2.5 constituents exposure with cardiometabolic risk factors. PP and CRI-2 were the targeted markers of long-term exposure to nitrate and ammonium. Inflammation may serve as a mediating factor between PM2.5 constituents and dyslipidemia, which enhance current understanding of potential pathways for PM2.5-induced preclinical cardiovascular responses.


Assuntos
Poluentes Atmosféricos , Fatores de Risco Cardiometabólico , Inflamação , Material Particulado , Material Particulado/análise , Humanos , Poluentes Atmosféricos/análise , China , Biomarcadores/sangue , Masculino , Exposição Ambiental/estatística & dados numéricos , Poluição do Ar/estatística & dados numéricos , Poluição do Ar/efeitos adversos , Feminino , Pessoa de Meia-Idade , Cidades , Adulto , Doenças Cardiovasculares/epidemiologia , Fatores de Risco , Aprendizado de Máquina , Nitratos/análise
19.
Front Neurol ; 15: 1350116, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38694778

RESUMO

Introduction: This study aimed to assess the correlation between the blood urea nitrogen (BUN)-to-creatinine (BUN/Cr) ratio and adverse outcomes (AOs) at 3 months in patients with acute ischemic stroke (AIS) in the Korean population. Methods: This cohort study encompassed 1906 cases of AIS at a South Korean hospital from January 2010 to December 2016. To determine the linear correlation between the BUN/Cr ratio and AOs in AIS, a binary logistic regression model (BLRM) was employed. Additionally, generalized additive models and techniques for smooth curve fitting were utilized to reveal the nonlinear dynamics between the BUN/Cr ratio and AOs in patients with AIS. Results: The prevalence of AOs was 28.65%, with a median BUN/Cr ratio of 18.96. Following adjustments for covariates, the BLRM disclosed that the association between the BUN/Cr ratio and the risk of AOs in patients with AIS did not attain statistical significance. Nevertheless, a nonlinear relationship surfaced, pinpointing an inflection point at 21.591. To the left of this inflection point, a 31.42% reduction in the risk of AOs was noted for every 1-unit surge in the Z score of the BUN/Cr ratio [odds ratio (OR) = 0.686, 95% confidence interval (CI): 0.519, 0.906, p = 0.008]. On the right side of the inflection point, the effect size (OR = 1.405, 95% CI: 1.018, 1.902, p = 0.039) was determined. Conclusion: The findings of this study underscore the intricate nature of the relationship between the BUN/Cr ratio and 3-month outcomes in patients with AIS, establishing a robust groundwork for future investigations.

20.
Small ; : e2400673, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38700057

RESUMO

Parasitic side reactions and dendrites formation hinder the application of aqueous zinc ion batteries due to inferior cycling life and low reversibility. Against this background, N-methyl formamide (NMF), a multi-function electrolyte additive is applied to enhance the electrochemical performance. Studied via advanced synchrotron radiation spectroscopy and DFT calculations, the NMF additive simultaneously modifies the Zn2+ solvation structure and ensures uniform zinc deposition, thus suppressing both parasitic side reactions and dendrite formation. More importantly, an ultralong cycling life of 3115 h in the Zn||Zn symmetric cell at a current density of 0.5 mA cm-2 is achieved with the NMF additive. Practically, the Zn||PANI full cell utilizing NMF electrolyte shows better rate and cycling performance compared to the pristine ZnSO4 aqueous electrolyte. This work provides useful insights for the development of high-performance aqueous metal batteries.

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