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1.
ACS Appl Mater Interfaces ; 16(37): 49275-49285, 2024 Sep 18.
Article de Anglais | MEDLINE | ID: mdl-39231300

RÉSUMÉ

As an emerging high-efficiency energy conversion device, improving the output of triboelectric nanogenerators (TENGs) is still a key method to promote practical application of TENGs. This paper systematically investigated the influence of component composition, thickness, and surface morphology of the metal conducting layer on the performance of triboelectric nanogenerators. It has been established that these three factors have a significant influence on the output performance of TENGs. Among the four common metals Au, Pt, Ag, and Cu, the triboelectric nanogenerator achieves its maximum output when utilizing Ag as the conducting layer, with optimal performance observed at a thickness of 278 nm. TENGs with nanostructured conducting layers have better output as the nanostructure amplifies the induction charging area, thereby effectively augmenting the performance of TENGs. In particular, when contrasted with a triboelectric nanogenerator utilizing copper foil as the conducting layer alongside poly(vinylidene difluoride) and Nylon-11 as friction layers in the common work, the short-circuit current of the triboelectric nanogenerator increased by 2.3 times, and the maximum short-circuit current reached 149 µA when the conducting layer was replaced with Ag, and the enhanced triboelectric nanogenerator successfully illuminated 1536 commercial LEDs. In addition, the TENG-based smart insoles combined with pedometers can realize signal sensing and the real-time recording of steps during exercise. This research provides a new simple and reliable method to further improve the output of the TENG.

2.
Microorganisms ; 12(8)2024 Jul 29.
Article de Anglais | MEDLINE | ID: mdl-39203390

RÉSUMÉ

Nitrogen application significantly affects microorganisms in agricultural ecosystems. However, it is still unclear how nitrogen application affects soil chemical properties and microbial communities in purple mudstone weathering products. In this study, a field soil column experiment was conducted in a typical purple soil area with four nitrogen fertilizer application gradients of 0 [CK], 280 [N1], 560 [N2], and 840 [N3] N kg ha-1. Nitrogen addition decreased the bacterial chao1 value and increased the bacterial evenness index. For both α- and ß-diversity, the effect of nitrogen addition on bacteria was much greater than that on fungi. Nitrogen addition significantly increased the relative abundance of Proteobacteria, Gemmatimonadetes, Bacteroidetes, and Ascomycota and decreased the relative abundance of Actinobacteria, Cyanobacteria, and Basidiomycota. Both pH and TC are the most important soil chemical properties influencing the bacterial and fungal communities. With the increases in the nitrogen application rate, the co-occurrence network complexity increased and then decreased. In summary, nitrogen fertilizer application could significantly change the soil chemical properties, microbial community diversity, composition, and co-occurrence network of purple mudstone weathering products. Among them, the N2 treatment (560 N kg∙ha-1) can more effectively stimulate the soil nutrients, enhance microbial network complexity, and promote further weathering of purple mudstone.

3.
J Colloid Interface Sci ; 678(Pt A): 689-702, 2024 Aug 30.
Article de Anglais | MEDLINE | ID: mdl-39216396

RÉSUMÉ

Solar-light-driven reduction of CO2 into renewable fuels has great potential in the production of sustainable energy, addressing the energy crisis and environmental problems simultaneously. However, it is a significant challenge to achieve high selectivity for the conversion of CO2 into CH4, which is a type of fuel with a high calorific value. Herein, carbon quantum dots (CQDs) were integrated with an oxygen vacancy modified nickel-based metal organic frameworks (NiMOFs) to form the CQDs-X/NiMOFV series, which exhibited superior performance for CO2 photoreduction into CH4 compared with pure NiMOFs in the presence of hole scavengers under visible light irradiation. The highest yielding rate of CH4 (1 mmol g-1 h-1) and selectivity (97.58 %) were obtained using a CQDs-25/NiMOFV catalyst. Most importantly, in diluted CO2 atmosphere, the yield of CH4 was almost unchanged and the selectivity of CH4 over CQDs-25/NiMOFV was higher than that in pure CO2. The superior performance of CQDs-25/NiMOFV may be attributed to the following two factors: (i) both CQDs and oxygen vacancies facilitate the transmission of electrons to promote the eight-electron reaction producing CH4, and (ii) oxygen vacancies can act as the electron trap to capture the photogenerated electrons to react with adsorbed CO2 on Ni2+. This study offers a valuable strategy for designing efficient photocatalysts to convert CO2 into CH4 with superior selectivity.

4.
Sci Total Environ ; 951: 175690, 2024 Nov 15.
Article de Anglais | MEDLINE | ID: mdl-39173748

RÉSUMÉ

Microplastics and antibiotics are receiving increasing attention as two emerging pollutants in the aquatic ecosystem. The absorption of antibiotics by microplastics can potentially intensify their impact on marine organisms and human health. However, the detailed mechanisms underlying this interaction remain to be elucidated. Through molecular dynamics (MD) simulations and density functional theory (DFT) calculations, this study investigated the adsorption of cefradine (CED) onto three typical microplastics (MPs)-polyethylene (PE), polypropylene (PP), and polyamide (PA). The results of the molecular dynamics simulations showed that the interaction energy between CED and microplastics followed the order of PA-CED > PP-CED > PE-CED, indicating that PA microplastics had the highest adsorption capacity for CED antibiotics. The total energy contribution of the microplastics-cefradine (MPs-CED) systems suggested that the van der Waals and electrostatic interactions were the two primary mechanisms for the adsorption of CED by these three microplastics. In DFT calculations, the adsorption of CED on PA was found to be significantly influenced by both electrostatic and van der Waals effects, while the main driving force in the adsorption of PE and PP is van der Waals effect. In addition, IGMH analysis and AIM topological analysis confirmed that the adsorption of CED on PA relied heavily on the synergistic effect of hydrogen bonding and the van der Waals effect. The findings of this study validate the results obtained from molecular dynamics simulations, laying a foundation for a comprehensive exploration of the interaction mechanisms between microplastics and organic pollutants by integrating MD simulations and DFT calculations.


Sujet(s)
Céfradine , Théorie de la fonctionnelle de la densité , Microplastiques , Simulation de dynamique moléculaire , Polluants chimiques de l'eau , Adsorption , Polluants chimiques de l'eau/composition chimique , Céfradine/composition chimique , Modèles chimiques , Antibactériens/composition chimique , Polypropylènes/composition chimique , Polyéthylène/composition chimique
5.
Biotechnol Adv ; 76: 108420, 2024 Nov.
Article de Anglais | MEDLINE | ID: mdl-39128577

RÉSUMÉ

Microorganisms co-exist and co-evolve in nature, forming intricate ecological communities. The interspecies cross-talk within these communities creates and sustains their great biosynthetic potential, making them an important source of natural medicines and high-value-added chemicals. However, conventional investigations into microbial metabolites are typically carried out in pure cultures, resulting in the absence of specific activating factors and consequently causing a substantial number of biosynthetic gene clusters to remain silent. This, in turn, hampers the in-depth exploration of microbial biosynthetic potential and frequently presents researchers with the challenge of rediscovering compounds. In response to this challenge, the coculture strategy has emerged to explore microbial biosynthetic capabilities and has shed light on the study of cross-talk mechanisms. These elucidated mechanisms will contribute to a better understanding of complex biosynthetic regulations and offer valuable insights to guide the mining of secondary metabolites. This review summarizes the research advances in microbial cross-talk mechanisms, with a particular focus on the mechanisms that activate the biosynthesis of secondary metabolites. Additionally, the instructive value of these mechanisms for developing strategies to activate biosynthetic pathways is discussed. Moreover, challenges and recommendations for conducting in-depth studies on the cross-talk mechanisms are presented.


Sujet(s)
Métabolisme secondaire , Voies de biosynthèse/génétique , Bactéries/métabolisme , Bactéries/génétique , Interactions microbiennes , Famille multigénique
6.
Small ; : e2405227, 2024 Aug 09.
Article de Anglais | MEDLINE | ID: mdl-39118565

RÉSUMÉ

Developing 3D hosts is one of the most promising strategies for putting forward the practical application of lithium(Li)-based anodes. However, the concentration polarization and uniform electric field of the traditional 3D hosts result in undesirable "top growth" of Li, reduced space utilization, and obnoxious dendrites. Herein, a novel dual-gradient 3D host (GDPL-3DH) simultaneously possessing gradient-distributed pore structure and lithiophilic sites is constructed by an electrospinning route. Under the synergistic effect of the gradient-distributed pore and lithiophilic sites, the GDPL-3DH exhibits the gradient-increased electrical conductivity from top to bottom. Also, Li is preferentially and uniformly deposited at the bottom of the GDPL-3DH with a typical "bottom-top" mode confirmed by the optical and SEM images, without Li dendrites. Consequently, an ultra-long lifespan of 5250 h of a symmetrical cell at 2 mA cm-2 with a fixed capacity of 2 mAh cm-2 is achieved. Also, the full cells based on the LiFePO4, S/C, and LiNi0.8Co0.1Mn0.1O2 cathodes all exhibit excellent performances. Specifically, the LiFePO4-based cell maintains a high capacity of 136.8 mAh g-1 after 700 cycles at 1 C (1 C = 170 mA g-1) with 94.7% capacity retention. The novel dual-gradient strategy broadens the perspective of regulating the mechanism of lithium deposition.

7.
Pestic Biochem Physiol ; 203: 106009, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-39084775

RÉSUMÉ

Fall armyworm, Spodoptera frugiperda (J. E. Smith), is a widely recognized global agricultural pest that has significantly reduced crop yields all over the world. S. frugiperda has developed resistance to various insecticides. Insect cytochrome P450 monooxygenases (CYPs or P450s) play an important role in detoxifying insecticides, leading to increased resistance in insect populations. However, the function of the specific P450 gene for lambda-cyhalothrin resistance in S. frugiperda was unclear. Herein, the expression patterns of 40 P450 genes in the susceptible and lambda-cyhalothrin-resistant populations were analyzed. Among them, CYP321A7 was found to be overexpressed in the resistant population, specifically LRS (resistance ratio = 25.38-fold) derived from a lambda-cyhalothrin-susceptible (SS) population and FLRS (a population caught from a field, resistance ratio = 63.80-fold). Elevated enzyme activity of cytochrome P450 monooxygenases (P450s) was observed for LRS (2.76-fold) and the FLRS (4.88-fold) as compared to SS, while no significant differences were observed in the activities of glutathione S-transferases and esterases. Furthermore, the knockdown of CYP321A7 gene by RNA interference significantly increased the susceptibility to lambda-cyhalothrin. Remarkably, the knockdown of CYP321A7 reduced the enzymatic activity of P450 by 43.7%, 31.9%, and 22.5% in SS, LRS, and FLRS populations, respectively. Interestingly, fourth-instar larvae treated with lambda-cyhalothrin at the LC30 dosage had a greater mortality rate due to RNA interference-induced suppression of CYP321A7 (with increases of 61.1%, 50.0%, and 45.6% for SS, LRS, and FLRS populations, respectively). These findings suggest a link between lambda-cyhalothrin resistance and continual overexpression of CYP321A7 in S. frugiperda larvae, emphasizing the possible importance of CYP321A7 in lambda-cyhalothrin detoxification in S. frugiperda.


Sujet(s)
Cytochrome P-450 enzyme system , Résistance aux insecticides , Insecticides , Nitriles , Pyréthrines , Spodoptera , Animaux , Pyréthrines/pharmacologie , Pyréthrines/toxicité , Spodoptera/effets des médicaments et des substances chimiques , Spodoptera/génétique , Nitriles/toxicité , Nitriles/pharmacologie , Cytochrome P-450 enzyme system/génétique , Cytochrome P-450 enzyme system/métabolisme , Insecticides/pharmacologie , Insecticides/toxicité , Résistance aux insecticides/génétique , Protéines d'insecte/génétique , Protéines d'insecte/métabolisme , Interférence par ARN , Inactivation métabolique , Larve/effets des médicaments et des substances chimiques , Larve/génétique
8.
Org Lett ; 26(31): 6664-6669, 2024 Aug 09.
Article de Anglais | MEDLINE | ID: mdl-39078505

RÉSUMÉ

A photocatalytic method for the ring-closing 1,7-enyne metathesis using the α-amino radical as an alkene deconstruction auxiliary is present. Preliminary mechanistic studies suggest that intramolecular 1,5-hydrogen atom transfer is the key to the generation and ß-scission of the α-amino radical, while the dearomatization of arenes and ring opening of cyclopropanes are the key to construct spirocyclic quinolin-2-ones. This approach highlights the potential of ring-closing 1,7-enyne metathesis, providing a green, efficient, and step-economical way for the synthesis of spirocyclic quinolin-2-ones.

9.
Zhongguo Zhong Yao Za Zhi ; 49(12): 3132-3143, 2024 Jun.
Article de Chinois | MEDLINE | ID: mdl-39041073

RÉSUMÉ

The traditional Chinese medicine(TCM) single preparation refers to the innovative TCM made from the whole or the effective part(including the effective ingredient) extract of a TCM single herb by modern technology. They have a long history of applications, definite effects and few side effects. It is an indispensable part of the research of innovative TCM. In recent years, with the optimization of national policies, the development of TCM single preparation shows a positive trend. However, because of the imbalance in the composition ratio, the need for expansion of indications, the need for further basic research, and the low conversion rate of existing patent achievements in universities and institutes, the TCM single preparation still has significant development space. In this review, we analyze and study the current situation, characteristics and difficulties of TCM single preparation, as well as relevant clinical application, basic research, industrialization and patent application information through statistical analysis of TCM single preparations in the Chinese Pharmacopoeia, which helps to provide direction for the development and research of single preparation of TCM.


Sujet(s)
Médicaments issus de plantes chinoises , Médecine traditionnelle chinoise , Médicaments issus de plantes chinoises/composition chimique , Humains
10.
Forensic Sci Int ; 361: 112102, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-38889602

RÉSUMÉ

Metabolites, as products of cellular metabolism, can provide a wealth of biological information and are less susceptible to degradation than other biomarkers due to their low molecular weight. Due to these properties, metabolites can be used as valuable biomarkers for forensic investigations. Knowing the timing of deposition of bloodstain could help to reconstruct crime scenes, draw conclusions about the time of the crime, and narrow down the circle of possible suspects. Previous studies have indicated that the concentration of some metabolites in blood is subject to circadian changes. However, the circadian metabolites of bloodstains have been still unclear. A total of sixty-four bloodstain samples were prepared under real conditions in three time categories (morning/noon (09:00 h ∼ 17:00 h), afternoon/evening (18:00 h ∼ 23:00 h) and night/early morning (24:00 h ∼ 08:00 h)). Fifty metabolites of bloodstains with significant differences were identified in the three time categories. Twenty-eight of these metabolites exhibited significant circadian changes. Finally, three independently contributing circadian metabolites were selected to build the logistic regression model, with an area under the curve of 0.91, 0.84 and 0.87 for the prediction of bloodstain deposition time in the morning/noon, afternoon/evening and night/early morning, respectively. The study indicated that circadian metabolites can be used for evaluating the timing of bloodstain deposition. This would provide a valuable perspective for analyzing the deposition time of biological traces in forensic investigations.


Sujet(s)
Taches de sang , Rythme circadien , Humains , Rythme circadien/physiologie , Mâle , Adulte , Femelle , Marqueurs biologiques/sang , Modèles logistiques , Adulte d'âge moyen , Jeune adulte , Médecine légale/méthodes , Facteurs temps
11.
Front Pediatr ; 12: 1381808, 2024.
Article de Anglais | MEDLINE | ID: mdl-38884105

RÉSUMÉ

Background: Exchange transfusion therapy is a complex and invasive procedure with a high risk coefficient. This method involves replacing the entire blood of a child with fresh blood with double circulating blood volume in a short period, typically in 1-2 h. This procedure can cause the body's internal environment to be unstable, which can put newborns under a lot of stress. This stress can lead to many, including abnormal laboratory biochemical examination, low or high blood pressure, and apnea. There is also the possibility of secondary infection and, in severe cases, cardiac arrest. This study investigated the effects of Humidified high-flow nasal cannula (HHFNC) ventilation on hemodynamic stability and oxygenation during exchange transfusion in neonates. Furthermore, the effects on brain metabolism and salivary cortisol during exchange transfusion were also analyzed. Methods: In this study, the control group consisted of 45 cases of children who underwent simple blood exchange between 1 May 2017, and 31 December 2019 control group. The observation group consisted of 33 cases of children who underwent blood exchange under HHFNC support between 1 January 2020, and 30 April 2022. The study compared various physiological parameters between the control and the observation group. These included blood gas analysis, pulmonary artery pressure, ejection fraction, invasive mean arterial pressure, heart rate, cerebral oxygenation, intestinal oxygenation, renal oxygenation, and duration of blood exchange. Furthermore, the study also compared the changes in brain metabolic and salivary cortisol indicators between the two groups of children. Results: The results did not reveal any significant difference in PH, PaO2, and duration of blood exchange between the control and the observation group. However, the observation group's invasive mean arterial pressure, ejection fraction, cerebral oxygenation, intestinal oxygenation, and renal oxygenation were higher than those of the control group. Furthermore, compared with the control group, the pulmonary artery pressure, heart rate, and PaCO2 were lower in the observation group. There was a statistically significant difference between the two groups of children in the relevant clinical indicators (total bilirubin, hemoglobin, SPO2, etc.) after exchange transfusion. After 1 h of blood exchange and after blood exchange, the salivary cortisol levels of the observation group were lower than the control group. The difference was statistically significant. The NAA/Cho and Cho/Cr values of the two groups of children were also significantly different. Conclusion: During blood exchange, unstable hemodynamics substantially impact organ oxygenation. The results of this study suggest that HHFNC and specific ventilation pressure support can improve the respiratory rate and help maintain blood flow stability and organ oxygenation. This technique can also reduce adverse reactions caused by blood exchange, minimizing patient stress and reducing the impact on brain metabolism.

12.
Heliyon ; 10(7): e28775, 2024 Apr 15.
Article de Anglais | MEDLINE | ID: mdl-38617962

RÉSUMÉ

Focusing on the situation of the low helium content in natural gas resource in China and the high cost of helium extraction, the OPEX prediction model of helium extraction that based on the Response Surface Methodology (RSM) is proposed. This method applies ASPEN-HYSYS software to simulate the helium extraction process flow for a given product composition, pressure, and temperature; Applying the Design Expert module for Response Surface Methodology(RSM) parameter design, combined with OPEX of existing projects, determine the key influencing factors and upper and lower limits of OPEX, and obtaining the corresponding OPEX for different parameter values; Applying the Box Behnken Design (BBD) principle to optimize the helium extraction process parameters of RSM, based on fitting results and parameter significance verification of second-order regression function, the OPEX prediction model is built.This method is applied to a domestic helium extraction project, and the unit helium extraction cost is between 100 and 119.52 yuan/m3, IRR is 13.37%. The result shows the project has economic benefit, and the method presents a good perspective application.

13.
Fitoterapia ; 176: 105981, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38685513

RÉSUMÉ

An investigation of EtOAc extract from the roots of Paeonia lactiflora yielded three new 30-noroleanane triterpenoids paeonenoides L-N (1-3) and one new oleanane triterpenoid paeonenoide O (4) together with 7 known compounds (5-11). Extensive spectrographic experiments were applied to identify the structures of 1-4, and their absolute configurations were unambiguously determined by theoretical calculations of ECD spectra, as well as the single-crystal X-ray diffraction analysis. Compounds 8, 9 and 10 were isolated from the Paeonia genus for the first time. Moreover, compounds 8, 9 and 11 showed inhibitory activities against LPS-induced nitric oxide (NO) production in RAW264.7 macrophages with the IC50 values of 72. 17 ± 4.74, 30.02 ± 2.03 and 28.34 ± 1.85 µM, respectively.


Sujet(s)
Monoxyde d'azote , Acide oléanolique , Paeonia , Composés phytochimiques , Racines de plante , Racines de plante/composition chimique , Paeonia/composition chimique , Souris , Animaux , Acide oléanolique/analogues et dérivés , Acide oléanolique/pharmacologie , Acide oléanolique/isolement et purification , Acide oléanolique/composition chimique , Cellules RAW 264.7 , Structure moléculaire , Monoxyde d'azote/métabolisme , Composés phytochimiques/pharmacologie , Composés phytochimiques/isolement et purification , Triterpènes/pharmacologie , Triterpènes/isolement et purification , Triterpènes/composition chimique , Chine , Macrophages/effets des médicaments et des substances chimiques
14.
J Agric Food Chem ; 72(10): 5247-5257, 2024 Mar 13.
Article de Anglais | MEDLINE | ID: mdl-38425052

RÉSUMÉ

Bioactivity screening revealed that the antifungal activities of EtOAc extracts from coculture broths of Trametes versicolor SY630 with either Vanderbylia robiniophila SY341 or Ganoderma gibbosum SY1001 were significantly improved compared to that of monocultures. Activity-guided isolation led to the discovery of five aromatic compounds (1-5) from the coculture broth of T. versicolor SY630 and V. robiniophila SY341 and two sphingolipids (6 and 7) from the coculture broth of T. versicolor SY630 and G. gibbosum SY1001. Tramevandins A-C (1-3) and 17-ene-1-deoxyPS (6) are new compounds, while 1-deoxyPS (7) is a new natural product. Notably, compound 2 represents a novel scaffold, wherein the highly modified p-terphenyl bears a benzyl substituent. The absolute configurations of those new compounds were elucidated by X-ray diffraction, ECD calculations, and analysis of physicochemical constants. Compounds 1, 2, and 5-7 exhibited different degrees of antimicrobial activity, and the antifungal activities of compounds 6 and 7 against Candida albicans and Cryptococcus neoformans are comparable to those of fluconazole, nystatin, and sphingosine, respectively. Transcriptome analysis, propidium iodide staining, ergosterol quantification, and feeding assays showed that the isolated sphingolipids can extensively downregulate the late biosynthetic pathway of ergosterol in C. albicans, representing a promising mechanism to combat antibiotic-resistant fungi.


Sujet(s)
Agaricales , Antifongiques , Antifongiques/composition chimique , Trametes , Techniques de coculture , Candida albicans , Ergostérol , Sphingolipides/métabolisme , Tests de sensibilité microbienne
15.
mBio ; 15(4): e0240723, 2024 Apr 10.
Article de Anglais | MEDLINE | ID: mdl-38456703

RÉSUMÉ

The inactivated whole-virion vaccine, CoronaVac, is one of the most widely used coronavirus disease 2019 (COVID-19) vaccines worldwide. There is a paucity of data indicating the durability of the immune response and the impact of immune imprinting induced by CoronaVac upon Omicron infection. In this prospective cohort study, 41 recipients of triple-dose CoronaVac and 14 unvaccinated individuals were recruited. We comprehensively profiled adaptive immune parameters in both groups, including spike-specific immunoglobulin (Ig) G and IgA titers, neutralizing activity, B cells, circulating follicular helper T (cTfh) cells, CD4+ and CD8+ T cells, and their memory subpopulations at 12 months after the third booster dose and at 4 and 20 weeks after Omicron BA.5 infection. Twelve months after the third CoronaVac vaccination, spike-specific antibodies and cellular responses were detectable in most vaccinated individuals. BA.5 infection significantly augmented the magnitude, cross-reactivity, and durability of serum neutralization activities, Fc-mediated phagocytosis, nasal spike-specific IgA responses, memory B cells, activated cTfh cells, memory CD4+ T cells, and memory CD8+ T cells for both the ancestral strain and Omicron subvariants, compared to unvaccinated individuals. Notably, the increase in BA.5-specific immunity after breakthrough infection was consistently comparable to or higher than that of the ancestral strain, suggesting no evidence of immune imprinting. Immune landscape analyses showed that vaccinated individuals have better synchronization of multiple immune components than unvaccinated individuals upon heterologous infection. Our data provide detailed insight into the protective role of the inactivated COVID-19 vaccine in shaping humoral and cellular immunity to Omicron infection. IMPORTANCE: There is a paucity of data indicating the durability of the immune response and the impact of immune imprinting induced by CoronaVac upon Omicron breakthrough infection. In this prospective cohort study, the anti-severe acute respiratory syndrome coronavirus 2 adaptive responses were analyzed before and after the Omicron BA.5 infection. Our data provide detailed insight into the protective role of the inactivated COVID-19 vaccine in shaping humoral and cellular immune responses to heterologous Omicron infection. CLINICAL TRIAL: This study is registered with ClinicalTrials.gov as NCT05680896.


Sujet(s)
COVID-19 , Immunité muqueuse , Vaccins inactivés , Humains , Vaccins contre la COVID-19 , SARS-CoV-2 , Réinfections , Lymphocytes T CD8+ , Études prospectives , Immunoglobuline G , Immunoglobuline A , Anticorps antiviraux , Anticorps neutralisants
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 313: 124118, 2024 May 15.
Article de Anglais | MEDLINE | ID: mdl-38461562

RÉSUMÉ

As the most universally used anionic surfactant, ubiquitous existence and accumulation of sodium dodecyl benzene sulfonate (SDBS) in the environment has inevitably imposed the associated harmful impacts to plants due to producing excessive reactive oxygen species. However, the underlying hazardous mechanism of the SDBS-induced oxidative stress to plants at molecular level has never been reported. Here, the molecular interaction of AtPrxQ with SDBS was explored for the first time. The intrinsic fluorescence of AtPrxQ was quenched based on static quenching, and a single binding site of AtPrxQ towards SDBS and the potential interaction forces driven by hydrophobic interactions were predicted from thermodynamic parameters and molecular docking results. Besides, the interaction pattern of AtPrxQ and SDBS was also confirmed by the bio-layer interferometry with moderate binding affinity. Moreover, the structural changes of AtPrxQ along with the destructions of the protein framework and the hydrophobic enhancement around aromatic amino acids were observed upon binding with SDBS. At last, the toxic effects produced by SDBS on peroxidase activities and Arabidopsis seedlings growth were also characterized. Thus this work may provide insights on the molecular interactions of AtPrxQ with SDBS and assessments on the biological hazards of SDBS to plants even for the agriculture.


Sujet(s)
Arabidopsis , Arabidopsis/métabolisme , Simulation de docking moléculaire , Tensioactifs/composition chimique , Stress oxydatif , Antioxydants/pharmacologie , Benzènesulfonates/composition chimique
17.
Nanotechnology ; 35(23)2024 Mar 19.
Article de Anglais | MEDLINE | ID: mdl-38430570

RÉSUMÉ

Efficient and robust oxygen reduction reaction (ORR) catalysts are essential for the development of high-performance anion-exchange membrane fuel cells (AEMFC). To enhance the electrochemical performance of metal-organic frameworks of cobalt-based zeolite imidazolium skeleton (ZIF-67), this study reported a novel ZIF-67-4@CNT byin situgrowing carbon nanotubes (CNTs) on the surface of ZIF-67 via a mild two-step pyrolysis/oxidation treatment. The electrochemical results showed that the as-prepared ZIF-67-4@CNT after CTAB modification exhibited excellent catalytic activity with good stability, with Eonset, E1/2, and Ilimit, respectively were 0.98 V (versus RHE), 0.87 V (versus RHE) and 6.04 mA cm-2@1600 rpm, and a current retention rate of about 94.21% after polarized at 0.80 V for 10 000 s, which were all superior to that of the commercial 20 wt% Pt/C. The excellent ORR catalytic performance was mainly attributed to the large amount of thein situgrowing CNTs on the surface, encapsulated with a wide range of valence states of metallic cobalt.

18.
Mediterr J Hematol Infect Dis ; 16(1): e2024001, 2024.
Article de Anglais | MEDLINE | ID: mdl-38223482

RÉSUMÉ

Thalidomide is a therapeutic option for patients with ß-thalassemia by increasing fetal hemoglobin and thereby reducing the requirement for blood transfusions. However, information on changes in erythropoiesis and iron homeostasis during thalidomide treatment is lacking. This study investigated the effects of thalidomide treatment on hematologic, erythropoietic, and ironstatus parameters in 22 patients with transfusion-dependent ß-thalassemia (TDT). Thalidomide significantly improved anemia endpoints, including increases in hemoglobin (p<0.001), red blood cells (p<0.001), and hematocrit (p<0.001), as well as reducing erythropoietin levels (p=0.033) and ameliorating erythropoiesis. Thalidomide treatment significantly reduced serum iron levels (p=0.018) and transferrin saturation (p=0.039) and increased serum transferrin levels (p=0.030). Thalidomide had no observed effect on serum ferritin or hepcidin, but changes in hepcidin (r=0.439, p=0.041) and serum iron (r=-0.536, p=0.010) were significantly correlated with hemoglobin increment. This comprehensive study indicates that thalidomide treatment can ameliorate erythropoiesis and iron homeostasis in patients with TDT, thus supporting the effectiveness of this drug.

19.
Small ; 20(15): e2306912, 2024 Apr.
Article de Anglais | MEDLINE | ID: mdl-38009480

RÉSUMÉ

The integration of magnetic resonance imaging (MRI), cGAS-STING, and anti-CTLA-4 (aCTLA-4) based immunotherapy offers new opportunities for tumor precision therapy. However, the precise delivery of aCTLA-4 and manganese (Mn), an activator of cGAS, to tumors remains a major challenge for enhanced MRI and active immunotherapy. Herein, a theragnostic nanosphere Mn-CREKA-aCTLA-4-SS (MCCS) is prepared by covalently assembling Mn2+, silk sericin (SS), pentapeptide CREKA, and aCTLA-4. MCCS are stable with an average size of 160 nm and is almost negatively charged or neutral at pH 5.5/7.4. T1-weighted images showed MCCS actively targeted tumors to improve the relaxation rate r1 and contrast time of MRI. This studies demonstrated MCCS raises reactive oxygen species levels, activates the cGAS-STING pathway, stimulates effectors CD8+ and CD80+ T cells, reduces regulatory T cell numbers, and increases IFN-γ and granzyme secretion, thereby inducing tumor cells autophagy and apoptosis in vitro and in vivo. Also, MCCS are biocompatible and biosafe. These studies show the great potential of Mn-/SS-based integrative material MCCS for precision and personalized tumor nanotheragnostics.


Sujet(s)
Tumeurs , Séricines , Humains , Manganèse , Immunothérapie , Imagerie par résonance magnétique , Nucleotidyltransferases , Tumeurs/imagerie diagnostique , Tumeurs/thérapie
20.
J Pediatr Orthop B ; 33(2): 184-191, 2024 Mar 01.
Article de Anglais | MEDLINE | ID: mdl-37401488

RÉSUMÉ

To compare outcomes of type II phalangeal neck fractures in children who received closed reduction followed by splinting immobilization or by K-wire fixation. Furthermore, we analyzed the remodeling potential of residual deformities and the relationship between age and outcomes. Patients in Children's Hospital of Fudan University, Xiamen Hospital were included in the study from October 2015 to October 2018. We compared outcomes between the conservation group and operation group. Remodeling of residual deformities was calculated on a series of anteroposterior and lateral radiography. The correlation between age and outcomes was analyzed using Spearman's rank correlation coefficient. Forty patients (25 males) were enrolled. Nineteen patients had subtype IIa, 19 subtype IIb, and two subtype IIc fractures. Left hands were affected more than right hands, and small finger and proximal phalanx were more frequently involved. There were no significant differences between conservation group and operation group among excellent, good, and fair outcomes. And the outcomes were not significantly different between the IIa and IIb subtypes. An average sagittal remodeling rate was 88.5%, and coronal remodeling rate was 56.71%, respectively, in 13 patients with residual deformities. There was a significant correlation between age and final outcomes. Closed reduction and stable splint fixation may be an effective and economical initial treatment option. Fracture subtype does not seem to be a key factor for choosing treatment options. The fractured phalangeal neck had remodeling potential whether on sagittal or coronal plane. Younger age might be a predictor of better outcomes in children with type II phalanx neck fractures.


Sujet(s)
Fractures osseuses , Fractures du rachis , Mâle , Enfant , Humains , Résultat thérapeutique , Fractures osseuses/imagerie diagnostique , Fractures osseuses/chirurgie , Ostéosynthèse , Fils métalliques , Main , Ostéosynthèse interne , Études rétrospectives
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