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Search Results (261)

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19 pages, 2654 KiB  
Review
TSGA10 as a Model of a Thermal Metabolic Regulator: Implications for Cancer Biology
by Ali Amini, Farzad Taghizadeh-Hesary, John Bracht and Babak Behnam
Cancers 2025, 17(11), 1756; https://doi.org/10.3390/cancers17111756 - 23 May 2025
Abstract
TSGA10, a multifunctional protein critical for mitochondrial coupling and metabolic regulation, plays a paradoxical role in cancer progression and carcinogenesis. Here, we outline a potential mechanism by which TSGA10 mediates metabolism in oncogenesis and thermal modulation. Initially identified in spermatogenesis, TSGA10 interacts with [...] Read more.
TSGA10, a multifunctional protein critical for mitochondrial coupling and metabolic regulation, plays a paradoxical role in cancer progression and carcinogenesis. Here, we outline a potential mechanism by which TSGA10 mediates metabolism in oncogenesis and thermal modulation. Initially identified in spermatogenesis, TSGA10 interacts with mitochondrial Complex III: it directly binds cytochrome c1 (CytC1). In our model, TSGA10 optimizes electron transport to minimize reactive oxygen species (ROS) and heat production while enhancing Adenosine Triphosphate (ATP) synthesis. In cancer, TSGA10’s expression is context-dependent: Its downregulation in tumors like glioblastoma might disrupt mitochondrial coupling, promoting electron leakage, ROS accumulation, and genomic instability. This dysfunction would be predicted to contribute to a glycolytic shift, facilitating tumor survival under hypoxia. Conversely, TSGA10 overexpression in certain cancers suppresses HIF-1α, inhibiting glycolysis and metastasis. TSGA10 and HIF-1α engage in mutual counter-regulation—TSGA10 represses HIF-1α to sustain oxidative phosphorylation (OXPHOS), while HIF-1α suppression of TSGA10 under hypoxia or thermal stress amplifies glycolytic dependency. This interplay is pivotal in tumors adapting to microenvironmental stressors, such as cold-induced mitochondrial uncoupling, which mimics brown adipose tissue thermogenesis to reduce ROS and sustain proliferation. Tissue-specific TSGA10 expression further modulates cancer susceptibility: high levels in the testes and brain may protect against thermal and oxidative damage, whereas low expression in the liver permits HIF-1α-driven metabolic plasticity. Altogether, our model suggests that TSGA10 plays a central role in mitochondrial fidelity. We suggest that its crosstalk with oncogenic pathways position it as a metabolic rheostat, whose dysregulation fosters tumorigenesis through ROS-mediated mutagenesis, metabolic reprogramming, and microenvironmental remodeling. Targeting the hypothesized TSGA10-mediated mitochondrial coupling may offer therapeutic potential to disrupt cancer’s adaptive energetics and restore metabolic homeostasis. Full article
(This article belongs to the Special Issue Molecular Mechanisms of Cancer Development and Metastasis)
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33 pages, 5189 KiB  
Article
Modelling Geothermal Energy Extraction from Low-Enthalpy Oil and Gas Fields Using Pump-Assisted Production: A Case Study of the Waihapa Oilfield
by Rohit Duggal, John Burnell, Jim Hinkley, Simon Ward, Christoph Wieland, Tobias Massier and Ramesh Rayudu
Sustainability 2025, 17(10), 4669; https://doi.org/10.3390/su17104669 - 19 May 2025
Viewed by 206
Abstract
As the energy sector transitions toward decarbonisation, low-to-intermediate temperature geothermal resources in sedimentary basins—particularly repurposed oil and gas fields—have emerged as promising candidates for sustainable heat and power generation. Despite their widespread availability, the development of these systems is hindered by gaps in [...] Read more.
As the energy sector transitions toward decarbonisation, low-to-intermediate temperature geothermal resources in sedimentary basins—particularly repurposed oil and gas fields—have emerged as promising candidates for sustainable heat and power generation. Despite their widespread availability, the development of these systems is hindered by gaps in methodology, oversimplified modelling assumptions, and a lack of integrated analyses accounting for long-term reservoir and wellbore dynamics. This study presents a detailed, simulation-based framework to evaluate geothermal energy extraction from depleted petroleum reservoirs, with a focus on low-enthalpy resources (<150 °C). By examining coupling reservoir behaviour, wellbore heat loss, reinjection cooling, and surface energy conversion, the framework provides dynamic insights into system sustainability and net energy output. Through a series of parametric analyses—including production rate, doublet spacing, reservoir temperature, and field configuration—key performance indicators such as gross power, pumping requirements, and thermal breakthrough are quantified. The findings reveal that: (1) net energy output is maximised at optimal flow rate (~70 kg/s for a 90 °C reservoir), beyond which increased pumping offsets thermal gains; (2) doublet spacing has a non-linear impact on reinjection cooling, with larger distances reducing thermal interference and pumping energy; (3) reservoirs with higher temperatures (<120°C) offer significantly better thermodynamic and hydraulic performance, enabling pump-free or low-duty operations at higher flow rates; and (4) wellbore thermal losses and reinjection effects are critical in determining long-term viability, especially in low-permeability or shallow fields. This work demonstrates the importance of a coupled, site-specific modelling in assessing the geothermal viability of petroleum fields and provides a foundation for future techno-economic and sustainability assessments. The results inform optimal design strategies and highlight scenarios where the geothermal development of oil and gas fields can be both technically and energetically viable. Full article
(This article belongs to the Section Energy Sustainability)
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15 pages, 2856 KiB  
Article
Insights into Pd-Nb@In2Se3 Electrocatalyst for High-Performance and Selective CO2 Reduction Reaction from DFT
by Lin Ju, Xiao Tang, Yixin Zhang, Mengya Chen, Shuli Liu and Chen Long
Inorganics 2025, 13(5), 146; https://doi.org/10.3390/inorganics13050146 - 5 May 2025
Viewed by 302
Abstract
The electrochemical CO2 reduction reaction (eCO2RR), driven by renewable energy, represents a promising strategy for mitigating atmospheric CO2 levels while generating valuable fuels and chemicals. Its practical implementation hinges on the development of highly efficient electrocatalysts. In this study, [...] Read more.
The electrochemical CO2 reduction reaction (eCO2RR), driven by renewable energy, represents a promising strategy for mitigating atmospheric CO2 levels while generating valuable fuels and chemicals. Its practical implementation hinges on the development of highly efficient electrocatalysts. In this study, a novel dual-metal atomic catalyst (DAC), composed of niobium and palladium single atoms anchored on a ferroelectric α-In2Se3 monolayer (Nb-Pd@In2Se3), is proposed based on density functional theory (DFT) calculations. The investigation encompassed analyses of structural and electronic characteristics, CO2 adsorption configurations, transition-state energetics, and Gibbs free energy changes during the eCO2RR process, elucidating a synergistic catalytic mechanism. The Nb-Pd@In2Se3 DAC system demonstrates enhanced CO2 activation compared to single-atom counterparts, which is attributed to the complementary roles of Nb and Pd sites. Specifically, Nb atoms primarily drive carbon reduction, while neighboring Pd atoms facilitate oxygen species removal through proton-coupled electron transfer. This dual-site interaction lowers the overall reaction barrier, promoting efficient CO2 conversion. Notably, the polarization switching of the In2Se3 substrate dynamically modulates energy barriers and reaction pathways, thereby influencing product selectivity. Our work provides theoretical guidance for designing ferroelectric-supported DACs for the eCO2RR. Full article
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19 pages, 10209 KiB  
Article
Urine Metabolomic Patterns to Discriminate the Burnout Levels and Night-Shift-Related Stress in Healthcare Professionals
by Andreea Petra Ungur, Andreea-Iulia Socaciu, Maria Barsan, Armand Gabriel Rajnoveanu, Razvan Ionut, Carmen Socaciu and Lucia Maria Procopciuc
Metabolites 2025, 15(4), 273; https://doi.org/10.3390/metabo15040273 - 14 Apr 2025
Viewed by 468
Abstract
Burnout syndrome, which significantly impacts both individual and societal quality of life, is primarily characterized by three key criteria: depersonalization, emotional exhaustion, and low personal accomplishment, all linked to work-related stress. Purpose: Comparative evaluation of urine metabolite patterns that may discriminate the [...] Read more.
Burnout syndrome, which significantly impacts both individual and societal quality of life, is primarily characterized by three key criteria: depersonalization, emotional exhaustion, and low personal accomplishment, all linked to work-related stress. Purpose: Comparative evaluation of urine metabolite patterns that may discriminate the burnout levels and the effects of night shifts on healthcare professionals. The Maslach Burnout Inventory survey was administered to 64 physicians and nurses working day and night shifts, with scores for each criterion recorded. Methods: Urine samples were collected, and metabolomic patterns were analyzed using UHPLC-QTOF-ESI+-MS technology. This analysis employed both untargeted and semi-targeted metabolomics, coupled with multivariate and ANOVA statistics, utilizing the online Metaboanalyst 6.0 platform. Partial Least Squares Discriminant Analysis (PLSDA) was performed, along with VIP values, Random Forest graphs, and heatmaps based on 79 identified metabolites. These were further complemented by biomarker analysis (AUC ranking) and pathway analysis of metabolic networks. Results: The findings highlighted the biochemical effects of night shifts and their correlation with burnout scores from each dimension. Conclusions: This study demonstrated the involvement of three major metabolic pathways in diagnosing burnout: lipid metabolism, particularly related to steroid hormones (cortisol, cortisone, and androsterone metabolites); energetic metabolism, involving long-chain acylated carnitines as transporters of free fatty acids, which play a role in burnout control; and a third pathway affecting catecholamine metabolism (neurotransmitters derived from tyrosine, such as dopamine, adrenaline, and noradrenaline), as well as tryptophan metabolism (serotonin and melatonin metabolites) and amino acid metabolism (including aspartate, arginine, and valine). Full article
(This article belongs to the Special Issue Integration of Emerging Technologies in Metabolite Analysis)
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11 pages, 1117 KiB  
Article
The Inhomogeneous Road to Chiral Symmetry Breaking: A Ginzburg–Landau–Langevin Analysis
by Theo F. Motta and Gastão Krein
Symmetry 2025, 17(4), 568; https://doi.org/10.3390/sym17040568 - 9 Apr 2025
Viewed by 248
Abstract
We investigate the time evolution of the quark condensate toward a chiral symmetry broken phase in hot and dense quark matter using a field-theoretic quark model with nonlocal chiral-invariant four-fermion coupling. By purposely selecting a parameter set in which inhomogeneous phases are energetically [...] Read more.
We investigate the time evolution of the quark condensate toward a chiral symmetry broken phase in hot and dense quark matter using a field-theoretic quark model with nonlocal chiral-invariant four-fermion coupling. By purposely selecting a parameter set in which inhomogeneous phases are energetically disfavored, we nonetheless observe the emergence of metastable patterned configurations that appear to persist for remarkably long timescales. These findings suggest that even when not fully stable, inhomogeneous phases may play a significant role in the dynamics of chiral symmetry breaking and restoration. To gain deeper insight into these phenomena, we also analyze the impact of the dimensionality of coordinate space on both the formation and stability of inhomogeneous chiral condensates. Full article
(This article belongs to the Special Issue Chiral Symmetry, and Restoration in Nuclear Dense Matter)
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30 pages, 5789 KiB  
Article
Fischer–Tropsch Biofuel Production from Supercritical Water Gasification of Lignocellulosic Biomass: Process Modelling and Life-Cycle Assessment
by Dimitrios Katsourinis, Dimitrios Giannopoulos and Maria Founti
Processes 2025, 13(3), 895; https://doi.org/10.3390/pr13030895 - 18 Mar 2025
Viewed by 444
Abstract
The production of Fischer–Tropsch liquid biofuels from the supercritical water gasification (SCWG) of lignocellulosic biomass is energetically and environmentally assessed by coupling process modelling with Life-Cycle Assessment. A conceptual process model has been developed comprising the following stages: (a) the thermochemical conversion of [...] Read more.
The production of Fischer–Tropsch liquid biofuels from the supercritical water gasification (SCWG) of lignocellulosic biomass is energetically and environmentally assessed by coupling process modelling with Life-Cycle Assessment. A conceptual process model has been developed comprising the following stages: (a) the thermochemical conversion of lignocellulosic biomass in a supercritical water gasification (SCWG) reactor, (b) syngas upgrade through dry reforming (DRR), (c) liquid biofuel production from Fischer–Tropsch synthesis (FTS) and (d) FT product upgrade and refinement, so that diesel-like (FT—Diesel), gasoline-like (FT—Gasoline), and jet fuel-like (FT Jet Fuel) yields are predicted. Parametric studies have been performed, highlighting the effect of biomass concentration and SCWG temperature on end-product yields. Furthermore, alternative scenarios have been examined with respect to: (a) maximizing FT liquid biofuel yields and (b) minimizing heat requirements to potentially achieve a thermally self-sustained process. The results of the simulated process, including liquid biofuel yield and heat-demand predictions, are used as inputs in the inventories compiled for the Life-Cycle Assessment of the overall process. Agricultural and feedstock transportation stages have also been considered. Energetic and environmental benefits and challenges are highlighted through the quantification of Global Warming Potential (GWP), while special importance is assigned to following the REDII sustainability methodology and reference data. Full article
(This article belongs to the Special Issue Processes in Biofuel Production and Biomass Valorization)
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42 pages, 5203 KiB  
Article
Origins of Ultrasensitivity and Complex Signaling Dynamics of Cellular Hydrogen Peroxide and Peroxiredoxin
by Shengnan Liu, Jingbo Pi and Qiang Zhang
Antioxidants 2025, 14(2), 235; https://doi.org/10.3390/antiox14020235 - 18 Feb 2025
Viewed by 707
Abstract
Hydrogen peroxide (H2O2) plays a crucial role in cell signaling in response to physiological and environmental perturbations. H2O2 can oxidize typical 2-Cys peroxiredoxin (PRX) first into a sulfenic acid, which resolves into a disulfide that can [...] Read more.
Hydrogen peroxide (H2O2) plays a crucial role in cell signaling in response to physiological and environmental perturbations. H2O2 can oxidize typical 2-Cys peroxiredoxin (PRX) first into a sulfenic acid, which resolves into a disulfide that can be reduced by thioredoxin (TRX)/TRX reductase (TR). At high levels, H2O2 can also hyperoxidize sulfenylated PRX into a sulfinic acid that can be reduced by sulfiredoxin (SRX). Therefore, PRX, TRX, TR, and SRX (abbreviated as PTRS system here) constitute the coupled sulfenylation and sulfinylation cycle (CSSC), where certain oxidized PRX and TRX forms also function as redox signaling intermediates. Earlier studies have revealed that the PTRS system is capable of rich signaling dynamics, including linearity, ultrasensitivity/switch-like response, nonmonotonicity, circadian oscillation, and possibly, bistability. However, the origins of ultrasensitivity, which is fundamentally required for redox signal amplification, have not been adequately characterized, and their roles in enabling complex nonlinear dynamics of the PTRS system remain to be determined. Through in-depth mathematical modeling analyses, here we revealed multiple sources of ultrasensitivity that are intrinsic to the CSSC, including zero-order kinetic cycles, multistep H2O2 signaling, and a mechanism arising from diminished H2O2 removal at high PRX hyperoxidation state. The CSSC, structurally a positive feedback loop, is capable of bistability under certain parameter conditions, which requires embedding multiple sources of ultrasensitivity identified. Forming a negative feedback loop with cytosolic SRX as previously observed in energetically active cells, the mitochondrial PTRS system (where PRX3 is expressed) can produce sustained circadian oscillations through supercritical Hopf bifurcations. In conclusion, our study provided novel quantitative insights into the dynamical complexity of the PTRS system and improved appreciation of intracellular redox signaling. Full article
(This article belongs to the Section Antioxidant Enzyme Systems)
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14 pages, 7114 KiB  
Article
Preparation of Ultrafine Spherical Al-Mg Alloy and Its Energy Release Characteristics in Explosives
by Junhui Liu, Jie Yao, Zichao Wang, Wei Liu, Jianxin Nie and Shi Yan
Metals 2025, 15(2), 202; https://doi.org/10.3390/met15020202 - 14 Feb 2025
Viewed by 712
Abstract
The substitution of aluminum powder with highly reactive ultrafine aluminum-based metal fuels has a significant impact on the energy release of aluminum-containing energetic materials because of their excellent energy density and combustion performances. A series of ultrafine spherical Al-Mg alloy fuels with different [...] Read more.
The substitution of aluminum powder with highly reactive ultrafine aluminum-based metal fuels has a significant impact on the energy release of aluminum-containing energetic materials because of their excellent energy density and combustion performances. A series of ultrafine spherical Al-Mg alloy fuels with different contents of magnesium were prepared by close-coupled gas atomization technology. The properties of Al-Mg alloy powders of 13~15 μm were tested by SEM, TG-DSC, and laser ignition experiments. Results show that alloying with magnesium can significantly enhance thermal oxidation and combustion performance, leading to more oxidation weight gains and higher combustion heat release. HMX-based castable explosives with the same content of Al and the novel Al-Mg alloy were made and tested. Results show that the detonation performances of HMX/Al-Mg alloy/HTPB are better than HMX/Al/HTPB. Compared to the HMX/Al/HTPB explosive, the detonation heat of HMX/ Al-Mg alloy/HTPB was increased by 200 kJ/kg, the energy release efficiency was enhanced from 80.55% to 83.19%, the detonation velocity was increased by 114 m/s, and the shock wave overpressure at 5 m was increased by 83%. This research provides a new type of composite metal fuel for improving the combustion performance of Al powder. Full article
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16 pages, 4451 KiB  
Article
Phi-Value and NMR Structural Analysis of a Coupled Native-State Prolyl Isomerization and Conformational Protein Folding Process
by Ulrich Weininger, Maximilian von Delbrück, Franz X. Schmid and Roman P. Jakob
Biomolecules 2025, 15(2), 259; https://doi.org/10.3390/biom15020259 - 10 Feb 2025
Viewed by 654
Abstract
Prolyl cis/trans isomerization is a rate-limiting step in protein folding, often coupling directly to the acquisition of native structure. Here, we investigated the interplay between folding and prolyl isomerization in the N2 domain of the gene-3-protein from filamentous phage fd, which [...] Read more.
Prolyl cis/trans isomerization is a rate-limiting step in protein folding, often coupling directly to the acquisition of native structure. Here, we investigated the interplay between folding and prolyl isomerization in the N2 domain of the gene-3-protein from filamentous phage fd, which adopts a native-state cis/trans equilibrium at Pro161. Using mutational and Φ-value analysis, we identified a discrete folding nucleus encompassing the β-strands surrounding Pro161. These native-like interactions form early in the folding pathway and provide the energy to shift the cis/trans equilibrium toward the cis form. Variations distant from the Pro161-loop have minimal impact on the cis/trans ratio, underscoring the spatial specificity and localized control of the isomerization process. Using NMR spectroscopy, we determined the structures for both native N2 forms. The cis- and trans-Pro161 conformations are overall identical and exhibit only slight differences around the Pro161-loop. The cis-conformation adopts a more compact structure with improved backbone hydrogen bonding, explaining the approximately 10 kJ·mol−1 stability increase of the cis state. Our findings highlight that prolyl isomerization in the N2 domain is governed by a localized folding nucleus rather than global stability changes. This localized energetic coupling ensures that proline isomerization is not simply a passive, slow step but an integral component of the folding landscape, optimizing both the formation of native structure and the establishment of the cis-conformation. Full article
(This article belongs to the Special Issue Innovative Biomolecular Structure Analysis Techniques)
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17 pages, 8357 KiB  
Article
Aluminum–Silica Core–Shell Nanoparticles via Nonthermal Plasma Synthesis
by Thomas Cameron, Bailey Klause, Kristine Q. Loh and Uwe R. Kortshagen
Nanomaterials 2025, 15(3), 237; https://doi.org/10.3390/nano15030237 - 4 Feb 2025
Viewed by 859
Abstract
Aluminum nanoparticles (Al NPs) are interesting for energetic and plasmonic applications due to their enhanced size-dependent properties. Passivating the surface of these particles is necessary to avoid forming a native oxide layer, which can degrade energetic and optical characteristics. This work utilized a [...] Read more.
Aluminum nanoparticles (Al NPs) are interesting for energetic and plasmonic applications due to their enhanced size-dependent properties. Passivating the surface of these particles is necessary to avoid forming a native oxide layer, which can degrade energetic and optical characteristics. This work utilized a radiofrequency (RF)-driven capacitively coupled argon/hydrogen plasma to form surface-modified Al NPs from aluminum trichloride (AlCl3) vapor and 5% silane in argon (dilute SiH4). Varying the power and dilute SiH4 flow rate in the afterglow of the plasma led to the formation of varying nanoparticle morphologies: Al–SiO2 core–shell, Si–Al2O3 core–shell, and Al–Si Janus particles. Scanning transmission electron microscopy with a high-angle annular dark-field detector (STEM-HAADF) and energy-dispersive X-ray spectroscopy (EDS) were employed for characterization. The surfaces of the nanoparticles and sample composition were characterized and found to be sensitive to changes in RF power input and dilute SiH4 flow rate. This work demonstrates a tunable range of Al–SiO2 core–shell nanoparticles where the Al-to-Si ratio could be varied by changing the plasma parameters. Thermal analysis measurements performed on plasma-synthesized Al, crystalline Si, and Al–SiO2 samples are compared to those from a commercially available 80 nm Al nanopowder. Core–shell particles exhibit an increase in oxidation temperature from 535 °C for Al to 585 °C for Al–SiO2. This all-gas-phase synthesis approach offers a simple preparation method to produce high-purity heterostructured Al NPs. Full article
(This article belongs to the Section Synthesis, Interfaces and Nanostructures)
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13 pages, 2851 KiB  
Article
Overwintering Strategies and Post-Diapause Female Reproduction Fitness in the Willow Leaf Beetle Plagiodera versicolora (Coleoptera: Chrysomelidae)
by Jian Yan, Lin Zhang, Mingxuan Xu, Xiaofeng Zhang and Lvquan Zhao
Insects 2025, 16(2), 140; https://doi.org/10.3390/insects16020140 - 1 Feb 2025
Viewed by 637
Abstract
Diapause, a survival strategy utilized by many insects under severe environmental conditions, can generate costs that potentially affect post-diapause development and reproduction. The willow leaf beetle, Plagiodera versicolora, overwinters as an adult. This study investigated the cold hardiness-hardiness and energy utilization of [...] Read more.
Diapause, a survival strategy utilized by many insects under severe environmental conditions, can generate costs that potentially affect post-diapause development and reproduction. The willow leaf beetle, Plagiodera versicolora, overwinters as an adult. This study investigated the cold hardiness-hardiness and energy utilization of female P. versicolora, and their impact on post-diapause reproductive fitness. The supercooling point exhibited seasonal temperature variation, with the lowest points occurring in January and February, coinciding with the relatively lower ambient temperatures. Lipid content demonstrated a pronounced decline at the onset of diapause (from November to December) and stabilized from December to March. Glycogen content also showed a sharp decrease from November to January, subsequently stabilizing at relatively constant levels. In addition, trehalose content increased significantly when temperatures dropped (from November to January) and then decreased as temperatures rose (from January to March). There were no significant differences in the time from pairing to successful mating for post-diapause females compared with non-diapause females. However, mating duration and the pre-oviposition period for post-diapause individuals relative to non-diapause individuals increased, coupled with a reduction in the oviposition period, total number of eggs, number of egg clutches, and number of eggs per clutch; however, most importantly, there was no notable change in egg-hatching success. These results suggest that the cold-hardiness strategy of P. versicolora falls within the freeze-avoidance category, with energy usage predominantly reliant on lipids and carbohydrates during diapause initiation. Our findings also highlight that, although post-diapause females are capable of nutrient replenishment, the energetic demands of diapause result in considerable negative impacts on post-diapause female reproductive fitness. Full article
(This article belongs to the Special Issue Arthropod Reproductive Biology)
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13 pages, 5858 KiB  
Article
Temperature Sensing in Agarose/Silk Fibroin Translucent Hydrogels: Preparation of an Environment for Long-Term Observation
by Maria Micheva, Stanislav Baluschev and Katharina Landfester
Nanomaterials 2025, 15(2), 123; https://doi.org/10.3390/nano15020123 - 16 Jan 2025
Viewed by 2829
Abstract
Environmental changes, such as applied medication, nutrient depletion, and accumulation of metabolic residues, affect cell culture activity. The combination of these factors reflects on the local temperature distribution and local oxygen concentration towards the cell culture scaffold. However, determining the temporal variation of [...] Read more.
Environmental changes, such as applied medication, nutrient depletion, and accumulation of metabolic residues, affect cell culture activity. The combination of these factors reflects on the local temperature distribution and local oxygen concentration towards the cell culture scaffold. However, determining the temporal variation of local temperature, independent of local oxygen concentration changes in biological specimens, remains a significant technological challenge. The process of triplet–triplet annihilation upconversion (TTA-UC), performed in a nanoconfined environment with a continuous aqueous phase, appears to be a possible solution to these severe sensing problems. This process generates two optical signals (delayed emitter fluorescence (dF) and residual sensitizer phosphorescence (rPh)) in response to a single external stimulus (local temperature), allowing the application of the ratiometric-type sensing procedure. The ability to incorporate large amounts of sacrificial singlet oxygen scavenging materials, without altering the temperature sensitivity, allows long-term protection against photo-oxidative damage to the sensing moieties. Translucent agarose/silk fibroin hydrogels embedding non-ionic micellar systems containing energetically optimized annihilation couples simultaneously fulfill two critical functions: first, to serve as mechanical support (for further application as a cell culture scaffold); second, to allow tuning of the material response window to achieve a maximum temperature sensitivity better than 0.5 K for the physiologically important region around 36 °C. Full article
(This article belongs to the Section Nanoelectronics, Nanosensors and Devices)
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22 pages, 10397 KiB  
Article
Mannich Base Derived from Lawsone Inhibits PKM2 and Induces Neoplastic Cell Death
by Lucas Rubini-Dias, Tácio V. A. Fernandes, Michele P. de Souza, Déborah Hottz, Afonso T. Arruda, Amanda de A. Borges, Gabriel Ouverney, Fernando de C. da Silva, Luana da S. M. Forezi, Gabriel Limaverde-Sousa and Bruno K. Robbs
Biomedicines 2024, 12(12), 2916; https://doi.org/10.3390/biomedicines12122916 - 21 Dec 2024
Viewed by 1179
Abstract
Background/Objectives: Pyruvate kinase M2, a central regulator of cancer cell metabolism, has garnered significant attention as a promising target for disrupting the metabolic adaptability of tumor cells. This study explores the potential of the Mannich base derived from lawsone (MB-6a) to [...] Read more.
Background/Objectives: Pyruvate kinase M2, a central regulator of cancer cell metabolism, has garnered significant attention as a promising target for disrupting the metabolic adaptability of tumor cells. This study explores the potential of the Mannich base derived from lawsone (MB-6a) to interfere with PKM2 enzymatic activity both in vitro and in silico. Methods: The antiproliferative potential of MB-6a was tested using MTT assay in various cell lines, including SCC-9, Hep-G2, HT-29, B16-F10, and normal human gingival fibroblast (HGF). The inhibition of PKM2 mediated by MB-6a was assessed using an LDH-coupled assay and by measuring ATP production. Docking studies and molecular dynamics calculations were performed using Autodock 4 and GROMACS, respectively, on the tetrameric PKM2 crystallographic structure. Results: The Mannich base 6a demonstrated selective cytotoxicity against all cancer cell lines tested without affecting cell migration, with the highest selectivity index (SI) of 4.63 in SCC-9, followed by B16-F10 (SI = 3.9), Hep-G2 (SI = 3.4), and HT-29 (SI = 2.03). The compound effectively inhibited PKM2 glycolytic activity, leading to a reduction of ATP production both in the enzymatic reaction and in cells treated with this naphthoquinone derivative. MB-6a showed favorable binding to PKM2 in the ATP-bound monomers through docking studies (PDB ID: 4FXF; binding affinity scores ranging from −6.94 to −9.79 kcal/mol) and MD simulations, revealing binding affinities stabilized by key interactions including hydrogen bonds, halogen bonds, and hydrophobic contacts. Conclusions: The findings suggest that MB-6a exerts its antiproliferative activity by disrupting cell glucose metabolism, consequently reducing ATP production and triggering energetic collapse in cancer cells. This study highlights the potential of MB-6a as a lead compound targeting PKM2 and warrants further investigation into its mechanism of action and potential clinical applications. Full article
(This article belongs to the Special Issue Drug Resistance and Novel Targets for Cancer Therapy—Second Edition)
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23 pages, 1507 KiB  
Review
Mitochondrial Dysfunction in Cardiac Disease: The Fort Fell
by Ioannis Paraskevaidis, Christos Kourek, Dimitrios Farmakis and Elias Tsougos
Biomolecules 2024, 14(12), 1534; https://doi.org/10.3390/biom14121534 - 29 Nov 2024
Cited by 4 | Viewed by 1331
Abstract
Myocardial cells and the extracellular matrix achieve their functions through the availability of energy. In fact, the mechanical and electrical properties of the heart are heavily dependent on the balance between energy production and consumption. The energy produced is utilized in various forms, [...] Read more.
Myocardial cells and the extracellular matrix achieve their functions through the availability of energy. In fact, the mechanical and electrical properties of the heart are heavily dependent on the balance between energy production and consumption. The energy produced is utilized in various forms, including kinetic, dynamic, and thermal energy. Although total energy remains nearly constant, the contribution of each form changes over time. Thermal energy increases, while dynamic and kinetic energy decrease, ultimately becoming insufficient to adequately support cardiac function. As a result, toxic byproducts, unfolded or misfolded proteins, free radicals, and other harmful substances accumulate within the myocardium. This leads to the failure of crucial processes such as myocardial contraction–relaxation coupling, ion exchange, cell growth, and regulation of apoptosis and necrosis. Consequently, both the micro- and macro-architecture of the heart are altered. Energy production and consumption depend on the heart’s metabolic resources and the functional state of the cardiac structure, including cardiomyocytes, non-cardiomyocyte cells, and their metabolic and energetic behavior. Mitochondria, which are intracellular organelles that produce more than 95% of ATP, play a critical role in fulfilling all these requirements. Therefore, it is essential to gain a deeper understanding of their anatomy, function, and homeostatic properties. Full article
(This article belongs to the Special Issue Heart Diseases: Molecular Mechanisms and New Therapies)
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40 pages, 4759 KiB  
Article
Grid-Coupled Geothermal and Decentralised Heat Supply Systems in a Holistic Open-Source Simulation Model for 5GDHC Networks
by Constantin Völzel and Stefan Lechner
Sustainability 2024, 16(23), 10503; https://doi.org/10.3390/su162310503 - 29 Nov 2024
Cited by 1 | Viewed by 1074
Abstract
In order to reach climate protection goals at national or international levels, new forms of combined heating and cooling networks with ultra-low network temperatures (5GDHC) are viable alternatives to conventional heating networks. This paper presents a simulation library for 5GDHC networks as sustainable [...] Read more.
In order to reach climate protection goals at national or international levels, new forms of combined heating and cooling networks with ultra-low network temperatures (5GDHC) are viable alternatives to conventional heating networks. This paper presents a simulation library for 5GDHC networks as sustainable shared energy systems, developed in the object-oriented simulation framework OpenModelica. It comprises sub-models for residential buildings acting as prosumers in the network, with additional roof-mounted thermal systems, dynamic thermo-hydraulic representations of distribution pipes and storage, time-series-based sources for heating and cooling, and weather conditions adjustable to user-specified locations. A detailed insight into an in-house development of a sub-model for horizontal ground heat collectors is given. This sub-model is directly coupled with thermo-hydraulic network simulations. The simulation results of energy balances and energetic efficiencies for an example district are described. Findings from this study show that decentralised roof-mounted solar thermal systems coupled to the network can contribute 21% to the total source heat provided in the network while annual thermal gains from the distribution pipes add up to more than 18% within the described settings. The presented simulation library can support conceptual and advanced planning phases for renewable heating and cooling supply structures based on environmental sources. Full article
(This article belongs to the Section Energy Sustainability)
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