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1.
J Phys Chem A ; 2024 Oct 03.
Article de Anglais | MEDLINE | ID: mdl-39360616

RÉSUMÉ

n-Pentanol is acknowledged as a prospective alternative and a supplement to traditional fossil fuels. H-abstraction reaction assumes a pivotal role in initiating the chain reaction during n-pentanol combustion. To investigate the oxidation characteristics of n-pentanol, the composite quantum chemical methods CBS-QB3 and G4 are employed to obtain thermochemical and kinetic parameters in the H-abstraction reaction of n-pentanol. The calculated isobaric heat capacity provides accurate predictions of the experimental results. Branching ratios underscore that H-abstraction at the Cα site serves as the primary channel between n-pentanol and H/CH3/È®H2. For the reaction between n-pentanol and È®H, the Cß site emerges as the most favorable channel due to the significant variational effect. The overall rate coefficient for H-abstraction from n-pentanol by È®H radicals is expressed as k = 3565.11 × T2.93 exp (1465.44/T) (cm3 mol-1 s-1), and the data obtained at the CBS-QB3 level demonstrate good agreement with experimental observations. Furthermore, the original model is modified based on current results, and the improved model demonstrates superior predictive capabilities for jet-stirred reactor (JSR) data and ignition delay times. Reaction path and sensitivity analyses are employed to identify fuel consumption pathways and critical reactions in the combustion of n-pentanol.

2.
Trials ; 25(1): 635, 2024 Sep 30.
Article de Anglais | MEDLINE | ID: mdl-39350195

RÉSUMÉ

BACKGROUND: Lipid management based on cardiovascular risk level is the cornerstone of primary prevention of coronary artery disease (CAD), while the accuracy and adherence of traditional cardiovascular risk stratification have been questioned. Prevention strategies based on imaging screening for atherosclerotic plaques are found to be more objective and adherent in recent studies. This trial aims to investigate the role of coronary computed tomography angiography (CCTA) in guiding the primary prevention of CAD in a randomized controlled design. METHODS: Approximately 3400 middle-aged asymptomatic community participants will be recruited and randomized in a 1:1 ratio to a traditional cardiovascular risk score-guided (usual care group) or CCTA-guided (CCTA group) strategy. Participants with cardiovascular disease, prior lipid-lowering therapy, CCTA contraindication, or serious diseases that affect life span will be excluded. The intervention strategy includes blood pressure, blood glucose, and lipid management and lifestyle modifications. Blood pressure and glucose targets and lifestyle modification recommendations keep the same in both strategies, while lipid management is personalized based on traditional risk level or CCTA results, respectively. The primary outcome is the proportion of participants taking lipid-lowering medication regularly at both 6 and 12 months. The secondary outcomes include the proportion of participants achieving low-density lipoprotein cholesterol lowering targets at 12 months, mean changes in lipid levels from baseline to 12 months, barriers to adherence, adverse reactions related to CCTA examination, and cardiovascular events. DISCUSSION: The study is the first randomized clinical trial to examine the effectiveness of a CCTA-guided versus a traditional risk score-guided primary prevention strategy in an asymptomatic community-based population. TRIAL REGISTRATION: ClinicalTrials.gov NCT05725096. Registered on 2 February 2023.


Sujet(s)
Angiographie par tomodensitométrie , Coronarographie , Maladie des artères coronaires , Humains , Maladie des artères coronaires/imagerie diagnostique , Maladie des artères coronaires/prévention et contrôle , Coronarographie/effets indésirables , Coronarographie/méthodes , Adulte d'âge moyen , Chine , Essais contrôlés randomisés comme sujet , Maladies asymptomatiques , Femelle , Prévention primaire/méthodes , Mâle , Facteurs de risque de maladie cardiaque , Hypolipémiants/usage thérapeutique , Lipides/sang , Facteurs de risque , Appréciation des risques , Peuples d'Asie de l'Est
3.
Article de Anglais | MEDLINE | ID: mdl-39291649

RÉSUMÉ

Covalent organic frameworks (COFs) are typically prepared in the form of insoluble microcrystalline powders using batch solvothermal reactions that are energy-intensive and require long annealing periods (>120 °C, >72 h). Thus, their wide-scale adoption in a variety of potential applications is impeded by complications related to synthesis, upscaling, and processing, which also compromise their commercialization. Here we report a strategy to address both the need for scalable synthesis and processing approaches through the continuous, accelerated synthesis, and processing of imine- and hydrazone-linked COFs using a flow microreactor. The flow microreactor is capable of unprecedented COF productivities, up to 61,111 kg m-3 day-1, and provides control over key stages of COF formation, including nanoparticle growth, self-assembly, and precipitation. Additionally, the technique successfully yields highly crystalline and porous COFs in versatile macroscopic structures such as monoliths, membranes, prints, and packed beds. We also show that a COF synthesized using the flow microreactor acts as an excellent photocatalyst for the photocatalytic degradation of perfluorooctanoic acid (PFOA) outperforming the degradation efficiency of its batch analogue and other classical photocatalysts such as titanium dioxide (TiO2).

4.
Talanta ; 281: 126877, 2024 Sep 13.
Article de Anglais | MEDLINE | ID: mdl-39277933

RÉSUMÉ

The ubiquity of plastic products has led to an increased exposure to micro and nano plastics across diverse environments, presenting a novel class of pollutants with substantial health implications. Emerging research indicates their capacity to infiltrate human organs, posing risks of tissue damage and carcinogenesis. Given the prevalent consumption of beverages as a primary vector for these plastics' entry into the human system, there is an imperative need for the advancement of precise detection methodologies in liquids. In this study, we introduce a substrate comprising a Nickel Oxide (NiO) nanosheet array decorated with Silver Nanoparticles (AgNPs) for the Surface-Enhanced Raman Spectroscopy (SERS) analysis of micro//nano plastics. This configuration, leveraging a unique nanowell architecture alongside silver plasmonic enhancement, demonstrates unparalleled sensitivity and repeatability in signal, facilitating the accurate quantification of these contaminants. Through the application of a portable Raman apparatus, this study successfully identifies prevalent micro/nano plastics including polystyrene (PS), polyethylene (PE), and polypropylene (PP), achieving detection sensitivities of 5 µg/mL, 25 µg/mL, and 25 µg/mL, respectively. Moreover, the substrate's efficacy extends to the detection of PS within commonly consumed beverages such as water, milk, and liquor with sensitivities of 25 µg/mL, 50 µg/mL, and 50 µg/mL, respectively. These findings highlight the substrate's potential as an expedient and effective sensor for the real-time monitoring of micro/nano plastic pollutants.

5.
J Hazard Mater ; 480: 135897, 2024 Sep 18.
Article de Anglais | MEDLINE | ID: mdl-39298966

RÉSUMÉ

Humankind are being exposed to a cocktail of chemicals, such as chemicals released from plastic food packaging. It is of great importance to evaluate the prevalence of plastic food packaging-derived chemicals pollution along the flow of food-human. We developed a robust and practical database of 2101 chemical features associated with plastic food packaging that combined data from three sources, 925 of which were acquired from non-target screening of chemical extracts from eight commonly used plastic food packaging materials. In this database, 625 features, especially half of the non-targets, were potential migrants who likely entered our bodies through dietary intake. Biomonitoring analysis of plastic chemical features in foodstuffs or human serum samples showed that approximately 78 % of the 2101 features were detectable and approximately half were non-targets. Of these, 17 plastic chemicals with high detection frequencies (DFs) in the human serum were confirmed to be functional chemical additives. Together, our work indicates that the number of plastic chemicals in our bodies could be far greater than previously recognized, and human exposure to plastic chemicals might pose a potential health risk.

6.
J Ethnopharmacol ; : 118819, 2024 Sep 18.
Article de Anglais | MEDLINE | ID: mdl-39303964

RÉSUMÉ

ETHNOPHARMACOLOGICAL RELEVANCE: Brain aging can promote neuronal damage, contributing to aging-related diseases like memory dysfunction. Buyang Huanwu Decoction (BYHWD), a traditional Chinese medicine formula known for tonifying qi and activating blood circulation, shows neuroprotective properties. Despite this, the specific mechanism by which BYHWD improves age-associated memory impairment (AAMI) has not been explored in existing literature. AIM OF THE STUDY: This study aimed to investigate the mechanism of BYHWD in the improvement of AAMI based on the "co-occurrence network regulation of intestinal microecology-host metabolism- immune function". MATERIALS AND METHODS: Firstly, D-galactose was performed to induce a rat model of AAMI. Learning and memory deficits was assessed by the Morris water maze test. H&E and Nissl staining were used to observe the pathological changes in neurons in the hippocampus of rats. Meanwhile, the levels of pro-inflammatory cytokines and the activation of antioxidant enzymes in rat serum were measured using ELISA. Finally, an integrated pharmacological approach was applied to explore the potential mechanism of BYHWD in improving AAMI. RESULTS: Our results indicated that BYHWD significantly mitigated the pathological structure of the hippocampus, reversed the levels of IL-6, TNF-α, GSH, and CAT in the serum, and improved learning and memory in aging rats. Transcriptomics combined with network pharmacology showed that energy metabolism and the inflammatory response were the key biological pathways for BYHWD to ameliorate AAMI. Integrative analysis of the microbiome and metabolomics revealed that BYHWD has the potential to restore the balance of abundance between probiotics and harmful bacteria, and ameliorate the reprogramming of energy metabolism caused by aging in the brain. The co-occurrence network analysis demonstrated that a strong correlation between the treatment of AAMI and the stability of intestinal microecology, host metabolism, and immune network. CONCLUSION: The findings of this study collectively support the notion that BYHWD has a superior therapeutic effect in an AAMI rat model. The mechanism involves regulating the "intestinal microecology-metabolism-immune function co-occurrence network" system to restore the composition of gut microbiota and metabolites. This further improves the metabolic phenotype of brain tissue and maintains the homeostasis of central nervous system's immunity, leading to an improvement in AAMI. Consequently, this study offers a unique perspective on the prevention and treatment of AAMI. And, BYHWD is also considered to be a promising preclinical treatment for improving AAMI.

7.
Front Microbiol ; 15: 1457703, 2024.
Article de Anglais | MEDLINE | ID: mdl-39286350

RÉSUMÉ

Human respiratory syncytial virus (hRSV) not only affects newborns but also older adults, contributing to a substantial worldwide burden of disease. However, only three approved hRSV vaccines remain commercially available to date. The development of a safe, practical and broad-spectrum vaccine suitable for all age groups remains extremely challenging. Using five different approaches-live-attenuated, recombinant-vector, subunit, particle-based, and mRNA-nearly 30 hRSV vaccine candidates are currently conducting clinical trials worldwide; moreover, > 30 vaccines are under preclinical evaluation. This review presents a comprehensive overview of these hRSV vaccines along with prospects for the development of infectious disease vaccines in the post-COVID-19 pandemic era.

8.
Micromachines (Basel) ; 15(9)2024 Aug 30.
Article de Anglais | MEDLINE | ID: mdl-39337762

RÉSUMÉ

Microelectromechanical System (MEMS) gyroscopes are inertial sensors used to measure angular velocity. Due to their small size and low power consumption, MEMS devices are widely employed in consumer electronics and the automotive industry. MEMS gyroscopes typically use closed-loop control systems, which often use PID controllers with fixed parameters. These classical PID controllers require a trade-off between overshoot and rise time. However, temperature variations can cause changes in the gyroscope's parameters, which in turn affect the PID controller's performance. To address this issue, this paper proposes an adaptive PID controller that adjusts its parameters in response to temperature-induced changes in the gyroscope's characteristics, based on the error value. A closed-loop control system using the adaptive PID was developed in Simulink and compared with a classical PID controller. The results demonstrate that the adaptive PID controller effectively tracked the changes in the gyroscope's parameters, reducing overshoot by 96% while maintaining a similar rise time. During gyroscope startup, the adaptive PID controller achieves faster stabilization with a 0.036 s settling time, outperforming the 0.06 s of the conventional PID controller.

9.
ACS Nano ; 18(33): 22431-22443, 2024 Aug 20.
Article de Anglais | MEDLINE | ID: mdl-39103298

RÉSUMÉ

Osteoclastic inhibition using antiresorptive bisphosphonates and osteogenic promotion using antisclerostin agents represent two distinct osteoporosis treatments in clinical practice, each individual treatment suffers from unsatisfactory therapeutic efficacy due to its indirect intervention in osteoclasis and promotion of osteogenesis simultaneously. Although this issue is anticipated to be resolved by drug synergism, a tempting carrier-free dual-medication nanoassembly remains elusive. Herein, we prepare such a nanoassembly made of antiresorptive alendronate (ALN) crystal and antisclerostin polyaptamer (Apt) via a nucleic acid-driven crystallization method. This nanoparticle can protect Apt from rapid nuclease degradation, avoid the high cytotoxicity of free ALN, and effectively concentrate in the cancellous bone by virtue of the bone-binding ability of DNA and ALN. More importantly, the acid microenvironment of cancellous bone triggers the disassociation of nanoparticles for sustained drug release, from which ALN inhibits the osteoclast-mediated bone resorption while Apt promotes osteogenic differentiation. Our work represents a pioneering demonstration of nucleic acid-driven crystallization of a bisphosphonate into a tempting carrier-free dual-medication nanoassembly. This inaugural advancement augments the antiosteoporosis efficacy through direct inhibition of osteoclasis and promotion of osteogenesis simultaneously and establishes a paradigm for profound understanding of the underlying synergistic antiosteoporosis mechanism of antiresorptive and antisclerostin components. It is envisioned that this study provides a highly generalizable strategy applicable to the tailoring of a diverse array of DNA-inorganic nanocomposites for targeted regulation of intricate pathological niches.


Sujet(s)
Alendronate , Cristallisation , Ostéoclastes , Ostéogenèse , Ostéoporose , Alendronate/composition chimique , Alendronate/pharmacologie , Ostéogenèse/effets des médicaments et des substances chimiques , Ostéoclastes/effets des médicaments et des substances chimiques , Ostéoclastes/métabolisme , Ostéoporose/traitement médicamenteux , Animaux , Souris , Agents de maintien de la densité osseuse/pharmacologie , Agents de maintien de la densité osseuse/composition chimique , Aptamères nucléotidiques/composition chimique , Aptamères nucléotidiques/pharmacologie , Cellules RAW 264.7 , Humains , Synergie des médicaments
10.
Gut Pathog ; 16(1): 45, 2024 Aug 30.
Article de Anglais | MEDLINE | ID: mdl-39215373

RÉSUMÉ

BACKGROUND: The use of gastrointestinal disease multiplex polymerase chain reaction (GI PCR) testing has become common for suspected gastrointestinal infection. Patients often test positive for multiple pathogens simultaneously through GI PCR, although the clinical significance of this is uncertain. METHODS: This retrospective cohort study investigated risk factors and clinical outcomes associated with detection of multiple (as opposed to single) pathogens on GI PCR. We included adult patients who underwent GI PCR testing from 2020 to 2023 and had one or more pathogens detected. We compared patients with multiple versus those with single pathogens and hypothesized that immunosuppression would be a risk factor for detection of multiple pathogens. We further hypothesized that, during the 90 days after GI PCR testing, patients with multiple pathogens would have worse clinical outcomes such as increased rates of emergency department (ED) visits, death, hospitalization, or ambulatory care visits. RESULTS: GI PCR was positive in 1341 (29%) of tested patients; 356 patients had multiple pathogens and 985 had one pathogen. The most common pathogens included Enteropathogenic Escherichia coli (EPEC, 27%), norovirus (17%), and Enteroaggregative E. coli (EAEC, 14%) in both multi- and singly positive patients. Immunosuppression was not associated with multiple pathogens (adjusted odds ratio [aOR] 1.35, 95% CI 0.96, 1.86). The factors most associated with multiple pathogens were Hispanic ethnicity (OR 1.86, 95% CI 1.42, 2.45) and chronic kidney disease (OR 1.69, 95% CI 1.13, 2.49). Patients with multiple pathogens were more likely to have ED visits during the 90 days after GI PCR testing (40% vs. 32%, p < 0.01), but they were not more likely to die, be hospitalized, or to have ambulatory medical visits. CONCLUSIONS: Immunosuppression was not associated with detection of multiple as opposed to single pathogens on GI PCR testing. There were worse clinical outcomes associated with detection of multiple pathogens, although these effects were modest.

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