bluuebunny/crossref_metadata_2025_split huggingface dataset:
Plasmon‐Enhanced Luminescence of Gold Nanoclusters by Using Silver and Gold Metal Nanostructures
Authors: Jofré Javiera , Douglas‐Gallardo Oscar A. , Bachmann Cristian , Danna Caroline S. , Troncoso Loreto , Peña‐Bermudes María , Iberlucea‐Salinas Isadora , Mendizábal Fernando , Osorio‐Román Igor O. , Segura Camilo 
Published: January 2025

AbstractPlasmonic materials can be utilized as effective platforms to enhance luminescent signals of luminescent metal nanoclusters (LMNCs). Both surface enhanced fluorescence (SEF) and shell‐isolated nanoparticle‐enhanced fluorescence (SHINEF) strategies take advantage of the localized and increased external electric field created around the plasmonic metal surface when excited at or near their characteristic plasmonic resonance. In this context, we present an experimental and computational study of different plasmonic composites, (Ag) Ag@SiO2 and (Au) Au@SiO2 nanoparticles, which were used to enhance the luminescent signal of Au nanoclusters coated with glutathione (GSH) molecule (Au25GSH NCs). This specific LMNC has recently attracted particular interest due to its luminescent response and characteristic photostability. Our study presents a wide characterization of the optical and morphologic features of the synthetized particles: plasmonic metal nanostructures and Au25GSH NCs through different experimental techniques including UV‐Visible, IR, luminescent spectroscopies, along with TEM and AFM microscopies. Additionally, we have carried out computational simulations based on time‐dependent density functional theory (TD‐DFT) and classical electrodynamics simulation based on Mie Theory to support our experimental findings. In this study, we report up to 3‐fold luminescence enhancement of Au25GSH NCs which is mainly attributed to slow dynamic SEF.
Direct Knitting of Pincer Palladium Complexes into Hyper‐Crosslinked Polymers for Superior Catalytic Performance in Suzuki‐Miyaura Reactions
Authors: Peng Mengjie , Zhang Yaqing , Wang Xiaoyan , Gao Hui , Tan Bien 
Published: January 2025

AbstractUsing a direct knitting strategy, we successfully prepared a novel heterogeneous catalyst consisting of pyridine‐bridged bis(imidazolium‐2‐ylidene) palladium complexes (CNC−Pd) embedded in a knitted network polymer. The resulting catalysts (HCP‐CNC−Pd‐d) exhibited high specific surface areas of 982 m2 g−1 with microporous and mesoporous structures. The large surface area enhances contact between the substrate and the catalytic center, while the strong chelation between CNC and the metal ion ensures the catalyst's durability. The HCP‐CNC−Pd‐d catalysts exhibited superior performance, achieving an impressive 99 % yield in the Suzuki coupling reaction between bromobenzene and phenylboronic acid. The catalyst also demonstrated good performance across a range of substrates in the Suzuki‐Miyaura coupling reactions. Furthermore, the catalyst could be recycled for over 10 cycles without any significant loss in activity and selectivity. This highly cost‐effective and convenient approach provides valuable insights into the design and application of heterogeneous catalysts in various fields.
Consistent Crust‐Core Interpolation and Its Effect on Non‐radial Neutron Star Oscillations
Authors: Canullán‐Pascual Martín O. , Mariani Mauro , Ranea‐Sandoval Ignacio F. , Orsaria Milva G. , Weber Fridolin 
Published: January 2025

ABSTRACTTo model the structure of neutron stars (NSs) theoretically, it is common to consider layers with different density regimes. Matching the equation of state (EoS) for the crust and core and obtaining a suitable description of these extreme conditions are crucial for understanding the properties of these compact objects. In this work, we construct 10 different NS EoSs incorporating three distinct crust models, which are connected to the core using a thermodynamically and causally consistent formalism. For cold NSs, we propose a linear relationship between pressure and energy density in a narrow region between the crust and core, effectively establishing an interpolation function in the pressure‐baryonic chemical potential plane. We then compare this EoS matching method with the classical approach, which neglects causal and thermodynamic consistency. We solve the Tolman–Oppenheimer–Volkoff equation to obtain the mass‐radius relationship and compare our results with observational constraints on NSs. Furthermore, we investigate the influence of the new matching formalism on non‐radial oscillation frequencies and damping times. Our findings suggest that the method used to glue the crust and core EoS impacts NS observables, such as the radius, oscillation frequencies, and damping times of non‐radial modes, which may be crucial for interpreting future gravitational wave observations from neutron star mergers or isolated pulsars. The effects are particularly noticeable for low‐mass NSs, regardless of the specific EoS model chosen. In particular, we find that the oscillation mode exhibits significant differences in frequencies among alternative matching methods, whereas the fundamental ‐mode remains unaffected by changes in crust models or interpolation schemes.
Heterologous Expression and Optimization of Fermentation Conditions for Recombinant Ikarugamycin Production
Authors: Evers Julia K. , Glöckle Anna , Wiegand Monique , Schuler Sebastian , Einsiedler Manuel , Gulder Tobias A. M. 
Published: January 2025

ABSTRACTIkarugamycin is a member of the natural product family of the polycyclic tetramate macrolactams (PoTeMs). The compound exhibits a diverse range of biological activities, including antimicrobial, antiprotozoal, anti‐leukemic, and anti‐inflammatory properties. In addition, it interferes with several crucial cellular functions, such as oxidized low‐density lipoprotein uptake in macrophages, Nef‐induced CD4 cell surface downregulation, and mechanisms of endocytosis. It is, therefore, used as a tool compound to study diverse biological processes. However, ikarugamycin commercial prices are very high, with up to 1300 € per 1 mg, thus limiting its application. We, therefore, set out to develop a high‐yielding recombinant production platform of ikarugamycin by screening different expression vectors, recombinant host strains, and cultivation conditions. Overall, this has led to overproduction levels of more than 100 mg/L, which, together with a straightforward purification protocol, establishes biotechnological access to affordable ikarugamycin enabling its increased use in biomedical research in the future.
In Vitro Biological Evaluation and In Silico Studies of a New Anthraquinone From Zingiber Cassumunar Roxb. in Type 2 Diabetes Management
Authors: Le Tho Huu , Nguyen Minh Hien , Le Anh Lan Tran , Nguyen Mai Thanh Thi , Nguyen Hai Xuan , Do Truong Nhat Van , Nguyen Nhan Trung 
Published: January 2025

ABSTRACTA novel diphenyl‐anthraquinone compound, cassuquinone A (CA), was isolated from the rhizomes of Zingiber cassumunar. Structural elucidation was accomplished using detailed nuclear magnetic resonance and high‐resolution mass spectroscopy‐electrospray ionization techniques, revealing a symmetrical anthraquinone core with methoxylated aromatic rings. CA exhibited potent α‐glucosidase (AR) inhibitory activity with an IC₅₀ of 11.72 µM, significantly more potent than the positive control, acarbose (IC₅₀ = 190.60 µM), highlighting its potential as an antidiabetic agent. Molecular docking studies indicated stable binding of CA to AR, with key interactions involving Arg315, Phe314, Glu411, Val232, and Ser240, contributing to its high docking score. Additionally, molecular dynamics simulations demonstrated that CA stabilizes the AR structure by reducing the enzyme's flexibility, especially within the active site, which may hinder substrate access and product release.
Proteomic Profiling of Potential E6AP Substrates via Ubiquitin‐based Photo‐Crosslinking Assisted Affinity Enrichment
Authors: Schuck Julian , Bernecker Christine , Scheffner Martin , Marx Andreas 
Published: January 2025

AbstractThe ubiquitin (Ub) ligase E6AP, encoded by the UBE3A gene, has been causally associated with human diseases including cervical cancer and Angelman syndrome, a neurodevelopmental disorder. Yet, our knowledge about disease‐relevant substrates of E6AP is still limited, presumably because at least some of these interactions are rather transient, a phenomenon observed for many enzyme‐substrate interactions. Here, we introduce a novel approach to trap such potential transient interactions by combining a stable E6AP‐Ub conjugate mimicking the active state of this enzyme with photo‐crosslinking (PCL) followed by affinity enrichment coupled to mass spectrometry (AE‐MS). To enable PCL, we equipped Ub with diazirine moieties at distinct positions. We validated our PCL assisted AE‐MS approach by identification of known (e. g. PSMD4, UCHL5) and potential new (e. g. MSH2) substrates of E6AP. Our findings suggest that PCL assisted AE‐MS is indeed suited to identify substrates of E6AP, thereby providing insights into E6AP‐associated pathologies, and, potentially, of other enzymes of the Ub‐conjugating system.
Methionine‐Derived Fluorescent Probes Targeting Mitochondria: A Tool for Real‐Time Oxidative Stress Monitoring in Live Cells
Authors: Pareek Niharika , Kalita Nripankar , Pandey Roopam , Samanta Animesh 
Published: January 2025

AbstractReactive oxygen species (ROS) play crucial roles in both cell signaling and defense mechanisms. Hypochlorous acid (HOCl), a strong oxidant, aids the immune response by damaging pathogens. In this study, we developed two pyridinium‐based fluorophores PSSM and PSSE for selective hypochlorite detection. Out of these two fluorescent probes, PSSM shows a strong turn‐on emission via a photoinduced electron transfer (PeT) mechanism, excellent mitochondrial localization, and rapid response to HOCl with high selectivity among reactive oxygen species by achieving a detection limit of 2.41 μM. It successfully detects both exogenous and endogenous HOCl in live cells, enabling the study of HOCl's role at the organelle level. Structural analysis of PSSM via thioether oxidation confirmed by HPLC, NMR and HRMS further supports its specificity. Confocal imaging and flow cytometry studies further highlights its utility in investigating oxidative stress, positioning this fluorophore as a valuable tool for monitoring HOCl imbalances in biological systems.
Alkaline Earth Metal Enhancement of Cerium‐Manganese‐Based Three‐Dimensional Ordered Macroporous Catalysts for NO Oxidation
Authors: Xue Yingshan , Wang Ping , Yang Cheng , Zhang Tianbao , Zhang Xin , Xiong Jing , Sun Xiaohua , Wei Yuechang , Li Zhenxing 
Published: January 2025

AbstractNitrogen oxides are an industrial and domestic waste gas, which pollutes the air and affects health. In this paper, we use the template method to achieve the doping of alkaline earth metals, and the alkaline earth metals are doped into cerium‐manganese‐based 3D ordered macroporous (3DOM) catalysts to detect NO oxidation. The introduction of alkaline earth metals can improve the stability and thickness of macroporous results, which increases the contact area between the catalyst and reactant gases. At the same time, alkaline earth metal doping can promote the formation of more oxygen vacancies and unsaturated structures and improve the catalytic activity of NO oxidation. The NO conversion rate of CM‐3Mg doped with 3% Mg was 61.25% at 250 °C, and the NO conversion rate was the highest at 303 °C, which was 79.2%. This study provides a promising catalyst candidate for NO oxidation in practical applications.
Exploring the Metal‐Centered Reactivity of Isomeric, N‐Bridged Biscyclometalated Platinum(II) Complexes
Authors: Matharu Gunwant K. , Soto Miguel A. , Huang Ben Zhen , Lelj Francesco , MacLachlan Mark J. 
Published: January 2025

AbstractThe field of platinum chemistry is ubiquitous in the research of anticancer drugs and new OLED materials. Within the vast library of existing compounds, the majority of work focuses on complexes in the +2 and +4 oxidation states, with comparatively few examples of PtIII complexes reported without bridging ligands. PtIII complexes with metal‐metal bonding can be made by mild oxidation of PtII complexes having bis(phenylpyridine) ligands. Here, we report the synthesis and characterization of two new PtII complexes bearing tetradentate N‐bridged bis(phenylpyridine) ligands with N^C*C^N and C^N*N^C coordinating atoms. Through chemical oxidation with PhICl2 and N‐chlorosuccinimide, we obtained four new complexes containing PtIV and PtIII centres. The dynamics of the PtIII complexes were explored by variable‐temperature NMR studies and showed surprisingly free rotation of the appended N‐aryl group. This work uncovers the importance of the destabilizing nature of the bulky N‐aryl group on intermetallic bonds, and sheds light on how the molecular rotation observed in the PtIII compounds could inspire new molecular rotors driven by intermetallic bonds.
All‐Optical Spatial Self‐Phase and Cross Phase Modulation Using an NLO Active Pyrylium Dye towards an Optical OR Gate
Authors: Saif Safna , Lekshmanan Lekshmi , Sankar Karthika , Thomas Titu , Pillai Saju , Ajayaghosh Ayyappanpillai , Rose Thankamani Priya 
Published: January 2025

AbstractAll‐optical modulation and optical switching with nonlinear materials are integral parts of the advancing all‐optical communication network. This report discusses the synthesis of a promising pyrylium dye, pyrylium‐NH2 for NLO based applications and probes its spatial self‐phase and cross phase modulation (XPM) properties. This dye can be effectively used for all‐optical modulation and OR logic gate operation. A 532 nm DPSS laser of tunable power is used to study the intensity dependent nonlinear refractive indices (n2) of the dye in ethanol, methanol and acetone. The dye has shown significant n2 compared to the existing literature. Concentration dependence, incident intensity dependence and temporal evolution of the far field diffraction annuli rings in these three solvents were studied. The all‐optical modulation of a weak signal beam is demonstrated using a high intensity pump beam via cross phase modulation, paving the way to optical switching applications.
CMPK2 promotes NLRP3 inflammasome activation via mtDNA‐STING pathway in house dust mite‐induced allergic rhinitis
Authors: Zheng YaoMing , Xie YaDong , Li JiaYing , Cao YuJie , Li Min , Cao Qing , Han MiaoMiao , Lou HongFei , Shu YiLai , Xiao Hui , Li HuaBin 
Published: January 2025

AbstractBackgroundHouse dust mite (HDM) is the leading allergen for allergic rhinitis (AR). Although allergic sensitisation by inhaled allergens renders susceptible individuals prone to developing AR, the molecular mechanisms driving this process remain incompletely elucidated.ObjectiveThis study aimed to elucidate the molecular mechanisms underlying HDM‐induced AR.MethodsWe examined the expression of cytidine/uridine monophosphate kinase 2 (CMPK2), STING and the NLRP3 inflammasome in both AR patients and mice. Additionally, we investigated the role of CMPK2 and STING in the activation of the NLRP3 inflammasome in AR.ResultsThe expression of CMPK2, STING and the NLRP3 inflammasome was significantly increased in the nasal mucosa of AR patients compared to non‐AR controls. A positive correlation was found between CMPK2 expression and the levels of STING, NLRP3, ASC, CASP1 and IL‐1β. HDM treatment up‐regulated the expression of CMPK2, and CMPK2 overexpression enhanced NLRP3 inflammasome activation in human nasal epithelial cells (HNEPCs). Additionally, mitochondrial reactive oxygen species (mtROS) production following HDM exposure contributed to mitochondrial dysfunction and the release of mitochondrial DNA (mtDNA), which activated the cyclic GMP‐AMP synthase (cGAS)‐STING pathway. Remarkably, depletion of mtDNA or inhibition of STING signalling reduced HDM‐induced NLRP3 inflammasome activation in HNEPCs. In vivo, genetic knockout of CMPK2 or STING alleviated NLRP3 inflammasome activation and ameliorated clinical symptoms of AR in mice.ConclusionsOur results suggest that HDM promotes the activation of NLRP3 inflammasome through the up‐regulation of CMPK2 and ensuing mtDNA‐STING signalling pathway, hence revealing additional therapeutic target for AR.Key points
Cytidine/uridine monophosphate kinase 2 (CMPK2) expression is up‐regulated in the nasal mucosa of patients and mice with allergic rhinitis (AR).
CMPK2 caused NLRP3 inflammasome activation via mitochondrial DNA (mtDNA)‐STING pathway.
Blocking CMPK2 or STING signalling significantly reduced the activation of NLRP3 in house dust mite (HDM)‐challenged mice and human nasal epithelial cells (HNEPCs).
Naringenin Inhibits Ferroptosis in Renal Tubular Epithelial Cells of Diabetic Nephropathy Through SIRT1/FOXO3a Signaling Pathway
Authors: Zhou Yi , Hu Tianchi , Zeng Huarong , Lin Lin , Xie Huan , Lin Rong , Huang Mengya 
Published: January 2025

ABSTRACTNaringenin has the potential to regulate ferroptosis and mitigate renal damage in diabetic nephropathy (DN). However, it remains unclear whether the naringenin's effects in DN are linked to its ability to regulate ferroptosis. This study investigated the potential anti‐ferroptosis properties of naringenin in high glucose (HG)‐induced renal tubular epithelial cell models. HK‐2 cells were cultured in HG medium to establish the DN cell model. HK‐2 cells were treated with different doses of naringenin to explore the effect of naringenin. The CCK‐8 results show that 50 μM ~ 200 μM of naringenin do not affect the viability of HK‐2 cells and the viability of HG‐induced HK‐2 cells increase in a dose‐dependent manner with naringenin treatment. Additionally, naringenin increased the levels of IL‐10 while decreasing the levels of IL‐1β, TNF‐α, IL‐6, and ROS in HG‐induced HK‐2 cells. Naringenin also reduced the levels of Fe2+, oxidized lipid ROS, MDA, 4‐HNE, ACSL4, and TFR1 in HG‐induced HK‐2 cells, while increasing the levels of non‐oxidized lipid ROS, SOD, GSH‐Px, SLC7A11, and GPX4. Meanwhile, naringenin restored the levels of MMP, ATP and MPTP opening, reduced OCR in HG‐induced HK‐2 cells. Furthermore, naringenin reversed the decreased expression of SIRT1, p‐FOXO3a, Nrf2 and Nuclear Nrf2 caused by HG. SIRT1 inhibitor EX527 and Nrf2 inhibitor ML385 attenuated the effects of naringenin on ferroptosis in HG‐induced HK‐2 cells, with EX527 demonstrating a stronger reversal effect on ferroptosis than ML385. These results suggest that naringenin inhibits ferroptosis in HG‐induced HK‐2 cells mainly through SIRT1/FOXO3a signaling pathway. This finding further enhanced our understanding of the mechanism behind naringenin's protective effect on DN.
Livestock shifts lepidopteran herbivore community due to intraguild elimination in Mediterranean agroforestry systems
Authors: Gaytán Álvaro , Canelo Tara , Pérez‐Izquierdo Carlos , Bonal Raúl 
Published: January 2025

AbstractLivestock grazing and trampling have been shown to reduce arthropod populations. Among arthropods, defoliating lepidopterans are particularly important for their impact on trees, the keystone structures of agroforestry systems. This study investigates the impact of livestock on the community of defoliating lepidopterans in agroforestry systems. We conducted both experimental and observational studies in the mid‐west and western regions of the Iberian Peninsula. In our field experiment, we sampled lepidopteran caterpillars in areas with livestock and in areas where livestock had been excluded for short and long periods. To validate our experimental results, we conducted a field survey across seven areas with and without livestock in the western Iberian Peninsula. Our findings revealed that after 2 years from the start of the experiment, the exclusion of livestock led to an increase in the abundance and species richness of lepidopterans, as well as shifts in their community composition. Our experimental findings were corroborated by our field survey. Interestingly, we found that the differences in community composition among exclusions were primarily due to species nestedness. Livestock exclusion consistently favored species that pupate in the ground, suggesting that livestock can alter the lepidopteran community by predating or accidentally trampling these species. This study underscores the significant role livestock play in modifying the community of defoliating lepidopterans in Mediterranean agroforestry systems (oak savannahs), with important implications for food webs and species interactions.
Lengths of Stay and Stopover Strategies of Western Sandpipers During Migration at Two Sites in British Columbia, Canada
Authors: Blondin Anne L. , Drever Mark C. , Flemming Scott A. , Easton Wendy E. , Maftei Mark , Zharikov Yuri , Warnock Nils , Nol Erica 
Published: January 2025

ABSTRACTAn accurate estimate of length of stay is necessary to derive passage population size for birds using a migration stopover site. In this study, we used VHF tags and a Motus automated telemetry array to estimate the length of stay of 385 Western Sandpipers (Calidris mauri) migrating through two stopover sites in British Columbia, Canada (Tofino and Fraser River Estuary) over the course of seven migration periods (three northward and four southward) from 2018 to 2021. The average length of stay of Western Sandpipers at the Tofino site on the west coast of Vancouver Island varied from 2 to 6 days and was shorter than the length of stay at the Fraser River Estuary, where the average length of stay varied from 4 to 8 days. At both sites, adult birds had shorter stopovers during southward migration, juvenile birds had longer stopovers compared to adults, and birds with lower mass at capture had longer stopovers. Morphology of adults and juveniles varied between the two sites. Birds captured at Tofino had shorter tarsi, as well as higher mass during southward migration compared to Western Sandpipers captured at the Fraser River Estuary. We also assessed prey availability at the two stopover sites, and we found that invertebrate density was greater in Tofino compared to the Fraser River Estuary during northward migration. Variation in minimum stopover length and morphology between sites suggests that individuals from different overwintering populations may use different routes along the west coast of North America. Western Sandpipers stopping at Tofino have a shorter length of stay during both migration periods and arrive heavier during southward migration, characteristics typical of “hop” migrants who travel shorter distances between stopover sites. Different stopover sites offer a unique set of site characteristics used by birds exhibiting varying migration strategies, highlighting the importance of conserving a diversity of migration stopover locations.