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1.
Adv Sci (Weinh) ; : e2402936, 2024 Sep 23.
Article de Anglais | MEDLINE | ID: mdl-39313862

RÉSUMÉ

The efficacy and safety of self-amplifying mRNA (saRNA) have been demonstrated in COVID-19 vaccine applications. Unlike conventional non-replicating mRNA (nrmRNA), saRNA offers a key advantage: its self-replication mechanism fosters efficient expression of the encoded protein, leading to substantial dose savings during administration. Consequently, there is a growing interest in further optimizing the expression efficiency of saRNA. In this study, in vitro adaptive passaging of saRNA is conducted under exogenous interferon pressure, which revealed several mutations in the nonstructural protein (NSP). Notably, two stable mutations, Q48P and I113F, situated in the NSP3 macrodomain (MD), attenuated its mono adenosine diphosphate ribose (MAR) hydrolysis activity and exhibited decreased replication but increased payload expression compared to wild-type saRNA (wt saRNA). Transcriptome sequencing analysis unveils diminished activation of the double-stranded RNA (dsRNA) sensor and, consequently, a significantly reduced innate immune response compared to wt saRNA. Furthermore, the mutant saRNA demonstrated less translation inhibition and cell apoptosis than wt saRNA, culminating in higher protein expression both in vitro and in vivo. These findings underscore the potential of reducing saRNA replication-dependent dsRNA-induced innate immune responses through genetic modification as a valuable strategy for optimizing saRNA, enhancing payload translation efficiency, and mitigating saRNA cytotoxicity.

2.
ACS ES T Eng ; 4(9): 2220-2233, 2024 Sep 13.
Article de Anglais | MEDLINE | ID: mdl-39296420

RÉSUMÉ

Carbon-based adsorbents used to remove recalcitrant water contaminants, including perfluoroalkyl substances (PFAS), are often regenerated using energy-intensive treatments that can form harmful byproducts. We explore mechanisms for sorbent regeneration using hydrated electrons (eaq -) from sulfite ultraviolet photolysis (UV/sulfite) in water. We studied the UV/sulfite treatment on three carbon-based sorbents with varying material properties: granular activated carbon (GAC), carbon nanotubes (CNTs), and polyethylenimine-modified lignin (lignin). Reaction rates and defluorination of dissolved and adsorbed model perfluorocarboxylic acids (PFCAs), perfluorooctanoic acid (PFOA) and perfluorobutanoic acid (PFBA), were measured. Monochloroacetic acid (MCAA) was employed to empirically quantify eaq - formation rates in heterogeneous suspensions. Results show that dissolved PFCAs react rapidly compared to adsorbed ones. Carbon particles in solution decreased aqueous reaction rates by inducing light attenuation, eaq - scavenging, and sulfite consumption. The magnitude of these effects depended on adsorbent properties and surface chemistry. GAC lowered PFOA destruction due to strong adsorption. CNT and lignin suspensions decreased eaq - formation rates by attenuating light. Lignin showed high eaq - quenching, likely due to its oxygenated functional groups. These results indicate that desorbing PFAS and separating the adsorbent before initiating PFAS degradation reactions will be the best engineering approach for adsorbent regeneration using UV/sulfite.

3.
Science ; 385(6715): 1354-1359, 2024 Sep 20.
Article de Anglais | MEDLINE | ID: mdl-39298588

RÉSUMÉ

Click reactions, which are characterized by rapid, high-yielding, and highly selective coupling of two reaction partners, are powerful tools in synthesis but are rarely reversible. Innovative strategies that reverse such couplings in a precise and on-demand manner, enabling a click-clip sequence, would greatly expand the technique's versatility. Herein, a click and clip reaction pair is demonstrated by manipulation of a sulfilimine linkage. Phenothiazines and amines are rapidly and quantitatively coupled through oxidative sulfilimine bond formation with N-bromosuccinimide, and the resulting sulfilimine bromides then undergo quantitative reversion to the phenothiazines and amines through photoreduction at 380 nanometers. This protocol enables fabrication of depolymerizable macromolecules and reversible modification of aminosaccharides, demonstrating high selectivity and efficiency for manipulating sulfilimine linkages in complex systems.

4.
J Sports Sci ; 42(16): 1548-1556, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-39259267

RÉSUMÉ

To investigate the associations of fundamental movement skill (FMS) proficiency with family factors, including socioeconomic status (SES) and caregiver characteristics, by sex in young children in China. Participants included 1,207 Chinese children aged 3-6 years in this cross-sectional study. Children's FMS, consisting of locomotor skills and object control (OC) skills, were assessed. Information on family SES and caregiver characteristics was reported by the parents. Sex differences in outcomes and the associations of FMS with family factors by sex were examined using SPSS 26.0. Boys scored significantly higher than girls in terms of overall FMS and OC skills (both p < 0.01). There were significant and negative associations between children's FMS and parental education level and parental body mass index (BMI), which varied by sex. Boys who were regularly cared for by parents had higher FMS and OC skill scores than did those who were primarily looked after by grandparents (both p < 0.01). This complex interplay between sex and family factors (i.e. parental education level, parental BMI, and the identity of primary caregiver) on FMS proficiency in young children underscores the urgent need for developing sex-tailored, family-involved, and socio-culturally adapted interventions to enhance FMS proficiency at the preschool stage.


Sujet(s)
Indice de masse corporelle , Aptitudes motrices , Humains , Mâle , Femelle , Aptitudes motrices/physiologie , Études transversales , Enfant d'âge préscolaire , Facteurs sexuels , Enfant , Chine , Niveau d'instruction , Classe sociale , Parents , Aidants , Mouvement/physiologie
5.
Angew Chem Int Ed Engl ; : e202413129, 2024 Sep 06.
Article de Anglais | MEDLINE | ID: mdl-39240087

RÉSUMÉ

Promoting the generation of triplet states is essential for developing efficient photocatalytic systems. This research presents a novel approach of host-stabilized through-space conjugation via the combination of covalent and non-covalent methods. The designed building block, 4,4'-(1,4(1,4)-dibenzene cyclohexaphane-1,4-diyl)bis(1-phenylpyridinium) chloride, features inherently stable through-space conjugation. When this block forms a 1:1 host-guest complex with cucurbit[8]uril, the through-space conjugation is further stabilized within the confined cavity. Both the generation and lifetime of triplet state are significantly increased, resulting from the host-stabilized through-space conjugation. Additionally, the ultrahigh binding constant of 6.58 × 1014 M-1 ensures the persistence of host-stabilization effect. As a result, the host-guest complex acts as a highly efficient catalyst in the photocatalytic oxidation of thioether and aromatic alcohol. In the photodegradation of lignin, a complex natural product, the host-guest complex also exhibits high efficiency, demonstrating its robustness. This line of research is anticipated to enrich the toolbox of supramolecular photochemistry and provide a strategy for fabricating efficient supramolecular photocatalysts.

6.
ACS Omega ; 9(33): 35961-35972, 2024 Aug 20.
Article de Anglais | MEDLINE | ID: mdl-39184486

RÉSUMÉ

In the construction of underground geological engineering, a variety of rocks were often encountered, and the engineering surrounding rocks was prone to shear fracturing. Shear mechanics tests were conducted on a variety of rocks under various joint angles. By studying the shear mechanical characteristics, acoustic emission behavior, and damage degree of the different rock types, we can obtain an insight into their bearing capacity and fracture mechanisms. An obvious inflection point from the elastic to plastic behavior can be observed for the specimens during the process of shear mechanics tests, and the shear behavior was divided into three phases. The acoustic emission signals significantly increased for coal during the second phase, while those of sandstone and shale start to increase during the third phase, which is from the peak point to fracture. The analyses of the shear failure and acoustic emission properties showed that the crack propagation angle increases as the normal stress of rock increases. It was proved that the joint angles and normal stresses of rock could effectively hinder the development of vertical fractures. Based on the shear failure and acoustic emission properties, a constitutive model capable of describing the shear behavior of different types of rocks was developed. This constitutive model can accurately describe the shear fracture properties of the various rocks. The shear failure properties and damage constitutive model of rocks in this study can be used to reduce engineering surrounding rock instability caused by shear.

7.
Proc Natl Acad Sci U S A ; 121(36): e2409955121, 2024 Sep 03.
Article de Anglais | MEDLINE | ID: mdl-39190351

RÉSUMÉ

Facing complex and variable emerging antibiotic pollutants, the traditional development of functional materials is a "trial-and-error" process based on physicochemical principles, where laborious steps and long timescales make it difficult to accelerate technical breakthroughs. Notably, natural biomolecular coronas derived from highly tolerant organisms under significant contamination scenarios can be used in conjunction with nanotechnology to tackling emerging contaminants of concern. Here, super worms (Tubifex tubifex) with high pollutant tolerance were integrated with nano-zero valent iron (nZVI) to effectively reduce the content of 17 antibiotics in wastewater within 7 d. Inspired by the synergistic remediation, nZVI-augmented worms were constructed as biological nanocomposites. Neither nZVI (0.3 to 3 g/L) nor worms (104 to 105 per liter) alone efficiently degraded florfenicol (FF, as a representative antibiotic), while their composite removed 87% of FF (3 µmol/L). Under antibiotic exposure, biomolecules secreted by worms formed a corona on and modified the nZVI particle surface, enabling the nano-bio interface greater functionality, including responsiveness, enrichment, and reduction. Mechanistically, FF exposure activated glucose-alanine cycle pathways that synthesize organic acids and amines as major metabolites, which were assembled into vesicles and secreted, thereby interacting with nZVI in a biologically response design strategy. Lactic acid and urea formed hydrogen bonds with FF, enriched analyte presence at the heterogeneous interface. Succinic and lactic acids corroded the nZVI passivation layer and promoted electron transfer through surface conjugation. This unique strategy highlights biomolecular coronas as a complex resource to augment nano-enabled technologies and will provide shortcuts for rational manipulation of nanomaterial surfaces with coordinated multifunctionalities.


Sujet(s)
Antibactériens , Fer , Antibactériens/composition chimique , Antibactériens/pharmacologie , Animaux , Fer/composition chimique , Fer/métabolisme , Couronne de protéines/composition chimique , Couronne de protéines/métabolisme , Polluants chimiques de l'eau/composition chimique , Polluants chimiques de l'eau/métabolisme , Oligochaeta/métabolisme , Dépollution biologique de l'environnement , Assainissement et restauration de l'environnement/méthodes , Nanocomposites/composition chimique
8.
Chemistry ; 30(53): e202401916, 2024 Sep 19.
Article de Anglais | MEDLINE | ID: mdl-39023507

RÉSUMÉ

Photodynamic therapy (PDT) can destroy tumor cells by generating singlet oxygen (1O2) under light irradiation, which is limited by the hypoxia of the neoplastic tissue. Chemodynamic therapy (CDT) can produce toxic hydroxyl radical (⋅OH) to eradicate tumor cells by catalytic decomposition of endogenous hydrogen peroxide (H2O2), the therapeutic effect of which is highly dependent on the concentration of H2O2. Herein, we propose a BODIPY-ferrocene conjugate with a balanced 1O2 and ⋅OH generation capacity, which can serve as a high-efficiency antitumor agent by combining PDT and CDT. The ferrocene moieties endow the as-prepared conjugates with the ability of chemodynamic killing of tumor cells. Moreover, combined PDT/CDT therapy with improved antitumor efficiency can be realized after exposure to light irradiation. Compared with the monotherapy by PDT or CDT, the BODIPY-ferrocene conjugates can significantly increase the intracellular ROS levels of the tumor cells after light irradiation, thereby inducing the tumor cell apoptosis at low drug doses. In this way, a synergistic antitumor treatment is achieved by the combination of PDT and CDT.


Sujet(s)
Antinéoplasiques , Composés du bore , Composés du fer II , Métallocènes , Photothérapie dynamique , Photosensibilisants , Oxygène singulet , Composés du fer II/composition chimique , Composés du fer II/pharmacologie , Métallocènes/composition chimique , Composés du bore/composition chimique , Composés du bore/pharmacologie , Humains , Photosensibilisants/composition chimique , Photosensibilisants/pharmacologie , Photosensibilisants/usage thérapeutique , Antinéoplasiques/composition chimique , Antinéoplasiques/pharmacologie , Oxygène singulet/métabolisme , Oxygène singulet/composition chimique , Lignée cellulaire tumorale , Apoptose/effets des médicaments et des substances chimiques , Peroxyde d'hydrogène/composition chimique , Radical hydroxyle/composition chimique , Radical hydroxyle/métabolisme , Espèces réactives de l'oxygène/métabolisme
9.
Environ Geochem Health ; 46(8): 276, 2024 Jul 03.
Article de Anglais | MEDLINE | ID: mdl-38958774

RÉSUMÉ

The occurrence of microplastics (MPs) and organic pollutants (OPs) residues is commonly observed in diverse environmental settings, where their interactions can potentially alter the behavior, availability, and toxicity of OPs, thereby posing risks to ecosystems. Herein, we particularly emphasize the potential for bioaccumulation and the biomagnification effect of MPs in the presence of OPs within the food chain. Despite the ongoing influx of novel information, there exists a dearth of data concerning the destiny and consequences of MPs in the context of food pollution. Further endeavors are imperative to unravel the destiny and repercussions of MPs/OPs within food ecosystems and processing procedures, aiming to gain a deeper understanding of the joint effect on human health and food quality. Nevertheless, the adsorption and desorption behavior of coexisting pollutants can be significantly influenced by MPs forming biofilms within real-world environments, including temperature, pH, and food constituents. A considerable portion of MPs tend to accumulate in the epidermis of vegetables and fruits, thus necessitating further research to comprehend the potential ramifications of MPs on the infiltration behavior of OPs on agricultural product surfaces.


Sujet(s)
Chaine alimentaire , Contamination des aliments , Microplastiques , Humains , Contamination des aliments/analyse , Bioaccumulation , Surveillance de l'environnement
10.
Patient Prefer Adherence ; 18: 1141-1150, 2024.
Article de Anglais | MEDLINE | ID: mdl-38863947

RÉSUMÉ

Objective: This study aimed to explore the needs and constraints to cardiac rehabilitation (CR) among patients diagnosed with coronary heart disease (CHD) in a community-based setting, and thereby facilitating the implementation of effective CR programs for this population. Methods: Focus group interviews were used as the primary research methodology. A total of 11 community-dwelling individuals diagnosed with CHD were selected from a community hospital to participate in in-depth interviews, aiming to discern and analyze their requirements and constraints experienced concerning medical resources and healthcare agency. The textual data underwent examination using Colaizzi's method of descriptive data analysis. Results: Deficits existed in the perceptions of patients with CHD within a community-based setting about their condition and CR, and in the social support for this disease. Patients expressed expectations for professional guidance during CR, gained an understanding about the beneficial effects of emotional stability on cognitive function. Patients expressed their thoughts and feelings regarding the diversity of physical exercise options. Two main themes and seven sub-themes were identified: (a) "Insufficient CR resources for patients": Lack of awareness about CHD; inadequate knowledge about secondary prevention/CR; insufficient support from family and friends. (b) "Patient CR initiative": Patient self-adjustment; expectation of professional rehabilitation guidance; stable emotions improving cognition; diverse attitudes and awareness of exercise. Conclusion: For more effective CR, community-based medical teams should provide more comprehensive and individualized rehabilitation programs. They should focus on individual variations and preferences of patients, as well as enhance the autonomy of patients and improve their self-care ability through effective empowerment measures.

11.
Environ Sci Technol ; 58(25): 11193-11202, 2024 Jun 25.
Article de Anglais | MEDLINE | ID: mdl-38859757

RÉSUMÉ

Per- and poly fluoroalkyl substances (PFASs) are often encountered with nonaqueous phase liquid (NAPL) in the groundwater at fire-fighting and military training sites. However, it is unclear how PFASs affect the dechlorination performance of sulfidized nanoscale zerovalent iron (S-nFe0), which is an emerging promising NAPL remediation agent. Here, S-nFe0 synthesized with controllable S speciation (FeS or FeS2) were characterized to assess their interactions with PFASs and their dechlorination performance for trichloroethylene NAPL (TCE-NAPL). Surface-adsorbed PFASs blocked materials' reactive sites and inhibited aqueous TCE dechlorination. In contrast, PFASs-adsorbed particles with improved hydrophobicity tended to enrich at the NAPL-water interface, and the reactive sites were re-exposed after the PFASs accumulation into the NAPL phase to accelerate dechlorination. This PFASs-induced phenomenon allowed the materials to present a higher reactivity (up to 1.8-fold) with a high electron efficiency (up to 99%) for TCE-NAPL dechlorination. Moreover, nFe0-FeS2 with a higher hydrophobicity was more readily enriched at the NAPL-water interface and more reactive and selective than nFe0-FeS, regardless of coexisting PFASs. These results unveil that a small amount of yet previously overlooked coexisting PFASs can favor selective reductions of TCE-NAPL by S-nFe0, highlighting the importance of materials hydrophobicity and transportation induced by S and PFASs for NAPL remediation.


Sujet(s)
Fer , Fer/composition chimique , Polluants chimiques de l'eau/composition chimique , Halogénation , Nappe phréatique/composition chimique
12.
Environ Sci Technol ; 58(25): 11063-11073, 2024 Jun 25.
Article de Anglais | MEDLINE | ID: mdl-38869036

RÉSUMÉ

Rhizosphere iron plaques derived from Fe-based nanomaterials (NMs) are a promising tool for sustainable agriculture. However, the requirement for flooded conditions to generate iron plaque limits the scope of the NM application. In this study, we achieved in situ Fenton oxidation of a highly chlorinated persistent organic pollutant (2,2',4,5,5'-pentachlorobiphenyl, PCB101) through iron plaque mediated by the interaction between α-Fe2O3 NMs and plant-rhizobacteria symbionts under dryland conditions. Mechanistically, the coexistence of α-Fe2O3 NMs and Pseudomonas chlororaphis JD37 stimulated alfalfa roots to secrete acidic and reductive agents as well as H2O2, which together mediated the rhizosphere Fenton reaction and converted α-Fe2O3 NMs into iron plaque rich in Fe(II)-silicate. Further verifications reproduced the Fenton reaction in vitro using α-Fe2O3 NMs and rhizosphere compounds, confirming the critical role of •OH in the oxidative degradation of PCB101. Significant reductions in PCB101 content by 18.6%, 42.9%, and 23.2% were respectively found in stem, leaf, and soil after a 120-d treatment, proving the effectiveness of this NMs-plant-rhizobacteria technique for simultaneously safe crop production and soil remediation. These findings can help expand the potential applications of nanobio interaction and its mediated iron plaque generation for both agricultural practice and soil remediation.


Sujet(s)
Fer , Polluants du sol , Fer/métabolisme , Polluants du sol/métabolisme , Nanostructures/composition chimique , Composés du fer III , Sol/composition chimique , Rhizosphère
13.
Sci Total Environ ; 944: 173929, 2024 Sep 20.
Article de Anglais | MEDLINE | ID: mdl-38871311

RÉSUMÉ

Antibiotics are commonly released into paddy fields as mixtures via human activities. However, the simultaneous extraction and detection of these chemicals from multiple media are technically challenging due to their different physicochemical properties, resulting in unclear patterns of their transport in the soil-rice system. In this study, a "quick, easy, cheap, effective, rugged, and safe" (QuEChERS) method was developed for the simultaneous analysis of 4 tetracyclines (TCs) and 4 fluoroquinolones (FQs) in the soil and rice tissues from a local poultry farm, and thereby the distribution patterns of the target antibiotics in the soil-rice system and their risk levels to the soil were analyzed. After parameter optimization, the calibration range used for the target antibiotics was 0.1-50 µg/L and each calibration curve was linear with a coefficient of determination (R2 > 0.995); The QuEChERS method achieved satisfactory recovery rates (70.3-124.6%) along with sensitive detection limits (0.005-0.21 ng/g) for TCs and FQs in the soil, root, stem, leaf, and grain. Among the 8 antibiotics, enrofloxacin (ENX), ciprofloxacin (CIP), oxytetracycline (OTC), and doxycycline (DOX) were detected around a poultry farm. The four antibiotics in the collected paddy soils around the poultry farm ranged from 7.1 ng/g to 395.5 ng/g. Notably, ENX and DOX had higher ecological risks (risk quotient values >1) than CIP and OTC in soil. ENX, CIP, and DOX were highly enriched in rice roots with concentrations up to 471.9, 857.3, and 547.4 ng/g, respectively, which were also detected in rice aboveground tissues. The findings may provide both technical and practical guidance for the understanding of antibiotic environmental behavior and risks.


Sujet(s)
Antibactériens , Surveillance de l'environnement , Oryza , Polluants du sol , Sol , Antibactériens/analyse , Polluants du sol/analyse , Oryza/composition chimique , Surveillance de l'environnement/méthodes , Sol/composition chimique , Fluoroquinolones/analyse , Tétracyclines/analyse
14.
Aquat Toxicol ; 273: 107006, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-38909583

RÉSUMÉ

Nanoplastics (NPs) and microcystin-LR (MC-LR) are two common and harmful pollutants in water environments, especially at aquafarm where are full of plastic products and algae. It is of great significance to study the toxic effects and mechanisms of the NPs and/or MC-LR on fish at the early stage. In this study, the embryo and larvae of a filtering-feeding fish, Aristichthys nobilis, were used as the research objects. The results showed that the survival and hatching rates of the embryo were not significantly affected by the environmental concentration exposure of these two pollutants. Scanning electron microscopy (SEM) observation displayed that NPs adhered to the surface of the embryo membrane. Transcriptomic and bioinformatic analyses revealed that the NPs exposure activated neuromuscular junction development and skeletal muscle fiber in larvae, and affected C5-Branched dibasic acid metabolism. The metabolic and biosynthetic processes of zeaxanthin, xanthophyll, tetraterpenoid, and carotenoid were suppressed after the MC-LR exposure, which was harmful to the retinol metabolism of fish. Excessive production of superoxide dismutase (SOD) was detected under the MC-LR exposure. The MC-LR and NPs coexposure triggered primary immunodeficiency and adaptive immune response, leading to the possibility of reduced fitness of A.nobilis during the development. Collectively, our results indicate that environmental concentration NPs and MC-LR coexposure could cause toxic damage and enhance sick risk in A.nobilis, providing new insights into the risk of NPs and MC-LR on filtering-feeding fish.


Sujet(s)
Embryon non mammalien , Larve , Toxines de la flore et de la faune marines , Microcystines , Polluants chimiques de l'eau , Microcystines/toxicité , Animaux , Toxines de la flore et de la faune marines/toxicité , Polluants chimiques de l'eau/toxicité , Embryon non mammalien/effets des médicaments et des substances chimiques , Larve/effets des médicaments et des substances chimiques , Microplastiques/toxicité , Poissons-chats/croissance et développement
15.
Chem Commun (Camb) ; 60(44): 5739-5742, 2024 May 28.
Article de Anglais | MEDLINE | ID: mdl-38742805

RÉSUMÉ

Here, an unusual MXene with a high ratio of oxygen functional groups was prepared by hydrothermal treatment of HF-etched MXene in aqueous KOH solution. The prepared MXene (H-220) exhibits ultrahigh specific capacitance (1030 F g-1 in a potential window of 0.85 V), and excellent rate and cycling performance simultaneously in a sulfuric acid electrolyte, and can act as an anode material of proton batteries.

16.
ChemSusChem ; : e202400827, 2024 May 24.
Article de Anglais | MEDLINE | ID: mdl-38785150

RÉSUMÉ

Ozonation water treatment technology has attracted increasing attention due to its environmental benign and high efficiency. Rutile PbO2 is a promising anode material for electrochemical ozone production (EOP). However, the reaction mechanism underlying ozone production catalyzed by PbO2 was rarely studied and not well-understood, which was in part due to the overlook of the electrochemistry-driven formation of oxygen vacancy (OV) of PbO2. Herein, we unrevealed the origin of the EOP activity of PbO2 starting from the electrochemical surface state analysis using density functional theory (DFT) calculations, activity analysis, and catalytic volcano modeling. Interestingly, we found that under experimental EOP potential (i. e., a potential around 2.2 V vs. reversible hydrogen electrode), OV can still be generated easily on PbO2 surfaces. Our subsequent kinetic and thermodynamic analyses show that these OV sites on PbO2 surfaces are highly active for the EOP reaction through an interesting atomic oxygen (O*)-O2 coupled mechanism. In particular, rutile PbO2(101) with the "in-situ" generated OV exhibited superior EOP activities, outperforming the (111) and (110) surfaces. Finally, by catalytic volcano modeling, we found that PbO2 is close to the theoretical optimum of the reaction, suggesting a superior EOP performance of rutile PbO2. All these analyses are in good agreement with previous experimental observations in terms of EOP overpotentials. This study provides the first volcano model to explain why rutile PbO2 is among the best metal oxide materials for EOP and provides new design guidelines for this rarely studied but industrially promising reaction.

17.
Genesis ; 62(3): e23603, 2024 06.
Article de Anglais | MEDLINE | ID: mdl-38738564

RÉSUMÉ

The vomeronasal organ (VNO) is a specialized chemoreceptive structure in many vertebrates that detects chemical stimuli, mostly pheromones, which often elicit innate behaviors such as mating and aggression. Previous studies in rodents have demonstrated that chemical stimuli are actively transported to the VNO via a blood vessel-based pumping mechanism, and this pumping mechanism is necessary for vomeronasal stimulation in behaving animals. However, the molecular mechanisms that regulate the vomeronasal pump remain mostly unknown. In this study, we observed a high level of expression of phosphodiesterase 5A (PDE5A) in the vomeronasal blood vessel of mice. We provided evidence to support the potential role of PDE5A in vomeronasal pump regulation. Local application of PDE5A inhibitors-sildenafil or tadalafil-to the vomeronasal organ (VNO) reduced stimulus delivery into the VNO, decreased the pheromone-induced activity of vomeronasal sensory neurons, and attenuated male-male aggressive behaviors. PDE5A is well known to play a role in regulating blood vessel tone in several organs. Our study advances our understanding of the molecular regulation of the vomeronasal pump.


Sujet(s)
Cyclic Nucleotide Phosphodiesterases, Type 5 , Organe voméronasal , Animaux , Organe voméronasal/métabolisme , Souris , Cyclic Nucleotide Phosphodiesterases, Type 5/métabolisme , Cyclic Nucleotide Phosphodiesterases, Type 5/génétique , Mâle , Inhibiteurs de la phosphodiestérase-5/pharmacologie , Tadalafil/pharmacologie , Citrate de sildénafil/pharmacologie , Phéromones/métabolisme , Agressivité/physiologie , Femelle , Souris de lignée C57BL
18.
RSC Adv ; 14(22): 15328-15336, 2024 May 10.
Article de Anglais | MEDLINE | ID: mdl-38741975

RÉSUMÉ

Isotope analysis of Sn plays a crucial role in geochemical studies and in monitoring nuclear contamination. Nevertheless, prevalent analytical techniques for examining Sn isotopes encounter the issue of isobaric interference, markedly impacting the accuracy of the test results. Laser resonance ionization mass spectrometry (LRIMS) can effectively overcome the difficulties associated with the isobaric interference inherent in commercial mass spectrometry. In this paper, different amounts of Sn were prepared on Re filaments by electrodeposition and tested via LRIMS. The results showed that the average detection efficiency of LRIMS decreased with increasing total Sn content from 1 µg to 4 µg, and the fluctuations in the test results among the samples increased significantly. Therefore, the electrodeposition process, as well as the composition and morphology of the deposits were characterized by SEM, EDS and XPS; results showed that the degradation of the samples with increasing Sn content was attributed to the complexity of the composition, micro-structure, valence of the deposits, and the interference of various elements. To cope with the anomalies encountered above, the deposits were heat-treated at 600 °C in a hydrogen atmosphere to eliminate detrimental impurities, like Cl, and Sn was effectively reduced to an almost singular atomic state. Furthermore, a titanium layer was covered on the surface of the heat-treated deposit by magnetron sputtering. Ultimately, a highly efficient and stable Sn atomic beam source with a sandwiched structure has been successfully developed and exhibits broad application prospect.

19.
Heliyon ; 10(8): e29814, 2024 Apr 30.
Article de Anglais | MEDLINE | ID: mdl-38681555

RÉSUMÉ

Despite the considerable efforts devoted to the toxicological assessment of nanoplastics, the effect of UV-irradiation induced aging, a realistic environmental process, on the toxicity of nanoplastics toward microalgae and its underlying mechanisms remain largely unknown. Herein, this study comparatively investigated the toxicities of polystyrene nanoplastics (nano-PS) and the UV-aged nano-PS on the eukaryotic alga Chlorella vulgaris, focusing on evaluating their inhibitory effects on carbon fixation. Exposure to environmentally relevant concentrations (0.1-10 mg/L) of nano-PS caused severe damage to chloroplast, inhibited the photosynthetic efficiency and electron transport, and suppressed the activities of carbon fixation related enzymes. Multi-omics results revealed that nano-PS interfered with energy supply by disrupting light reactions and TCA cycle and hindered the Calvin cycle, thereby inhibiting the photosynthetic carbon fixation of algae. The above alterations partially recovered after a recovery period. The aged nano-PS were less toxic than the pristine ones as evidenced by the mitigated inhibitory effect on algal growth and carbon fixation. The aging process introduced oxygen-containing functional groups on the surface of nano-PS, increased the hydrophilicity of nano-PS, limited their attachment on algal cells, and thus reduced the toxicity. The findings of this work highlight the potential threat of nanoplastics to the global carbon cycle.

20.
Intern Med J ; 54(8): 1292-1301, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-38563467

RÉSUMÉ

BACKGROUND AND AIMS: Sleep-disordered breathing (SDB) and nocturnal hypoxemia were known to be present in patients with chronic thromboembolic pulmonary hypertension (CTEPH), but the difference between SDB and nocturnal hypoxemia in patients who have chronic thromboembolic pulmonary disease (CTEPD) with or without pulmonary hypertension (PH) at rest remains unknown. METHODS: Patients who had CTEPH (n = 80) or CTEPD without PH (n = 40) and who had undergone sleep studies from July 2020 to October 2022 at Shanghai Pulmonary Hospital were enrolled. Nocturnal mean SpO2 (Mean SpO2) <90% was defined as nocturnal hypoxemia, and the percentage of time with a saturation below 90% (T90%) exceeding 10% was used to evaluate the severity of nocturnal hypoxemia. Logistic and linear regression analyses were performed to investigate the difference and potential predictor of SDB or nocturnal hypoxemia between CTEPH and CTEPD without PH. RESULTS: SDB was similarly prevalent in CTEPH and CTEPD without PH (P = 0.104), both characterised by obstructive sleep apnoea (OSA). Twenty-two patients with CTEPH were diagnosed with nocturnal hypoxemia, whereas only three were diagnosed with CTEPD without PH (P = 0.021). T90% was positively associated with mean pulmonary arterial pressure (mPAP) and pulmonary vascular resistance in patients with CTEPH and CTEPD without PH (P < 0.001); T90% was also negatively related to cardiac output in these patients. Single-breath carbon monoxide diffusing capacity, sex and mPAP were all correlated with nocturnal hypoxemia in CTEPH and CTEPD without PH (all P < 0.05). CONCLUSION: Nocturnal hypoxemia was worse in CTEPD with PH; T90%, but not SDB, was independently correlated with the hemodynamics in CTEPD with or without PH.


Sujet(s)
Hypertension pulmonaire , Hypoxie , Embolie pulmonaire , Syndromes d'apnées du sommeil , Humains , Femelle , Mâle , Adulte d'âge moyen , Hypoxie/étiologie , Embolie pulmonaire/complications , Embolie pulmonaire/physiopathologie , Sujet âgé , Syndromes d'apnées du sommeil/complications , Syndromes d'apnées du sommeil/physiopathologie , Hypertension pulmonaire/physiopathologie , Hypertension pulmonaire/étiologie , Hypertension pulmonaire/complications , Maladie chronique , Chine/épidémiologie , Polysomnographie
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