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Search Results (321)

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24 pages, 921 KiB  
Article
Towards Empowering Stakeholders Through Decentralized Trust and Secure Livestock Data Sharing
by Abdul Ghafoor, Iraklis Symeonidis, Anna Rydberg, Cecilia Lindahl and Abdul Qadus Abbasi
Cryptography 2025, 9(3), 52; https://doi.org/10.3390/cryptography9030052 - 23 Jul 2025
Viewed by 326
Abstract
Cybersecurity represents a critical challenge for data-sharing platforms involving multiple stakeholders, particularly within complex and decentralized systems such as livestock supply chain networks. These systems demand novel approaches, robust security protocols, and advanced data management strategies to address key challenges such as data [...] Read more.
Cybersecurity represents a critical challenge for data-sharing platforms involving multiple stakeholders, particularly within complex and decentralized systems such as livestock supply chain networks. These systems demand novel approaches, robust security protocols, and advanced data management strategies to address key challenges such as data consistency, transparency, ownership, controlled access or exposure, and privacy-preserving analytics for value-added services. In this paper, we introduced the Framework for Livestock Empowerment and Decentralized Secure Data eXchange (FLEX), as a comprehensive solution grounded on five core design principles: (i) enhanced security and privacy, (ii) human-centric approach, (iii) decentralized and trusted infrastructure, (iv) system resilience, and (v) seamless collaboration across the supply chain. FLEX integrates interdisciplinary innovations, leveraging decentralized infrastructure-based protocols to ensure trust, traceability, and integrity. It employs secure data-sharing protocols and cryptographic techniques to enable controlled information exchange with authorized entities. Additionally, the use of data anonymization techniques ensures privacy. FLEX is designed and implemented using a microservices architecture and edge computing to support modularity and scalable deployment. These components collectively serve as a foundational pillar of the development of a digital product passport. The FLEX architecture adopts a layered design and incorporates robust security controls to mitigate threats identified using the STRIDE threat modeling framework. The evaluation results demonstrate the framework’s effectiveness in countering well-known cyberattacks while fulfilling its intended objectives. The performance evaluation of the implementation further validates its feasibility and stability, particularly as the volume of evidence associated with animal identities increases. All the infrastructure components, along with detailed deployment instructions, are publicly available as open-source libraries on GitHub, promoting transparency and community-driven development for wider public benefit. Full article
(This article belongs to the Special Issue Emerging Trends in Blockchain and Its Applications)
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26 pages, 4733 KiB  
Article
Structural Characterization and Anti-Ultraviolet Radiation Damage Activity of Polysaccharides from Helianthus annuus (Sunflower) Receptacles
by Xiaochun Chen, Zhiying Wei, Xiaoying Mo, Yantong Lu, Guangjuan Pan, Zhenzhen Pan, Yaohua Li, Hui Tian and Xiaojiao Pan
Molecules 2025, 30(14), 2943; https://doi.org/10.3390/molecules30142943 - 11 Jul 2025
Viewed by 343
Abstract
Helianthus annuus L. (H. annuus) receptacles, a major agricultural by-product generated during seed processing, are currently underutilized. This study aimed to explore the valorization potential of this by-product by extracting H. annuus receptacles total polysaccharides (HRTP) and characterizing their potential [...] Read more.
Helianthus annuus L. (H. annuus) receptacles, a major agricultural by-product generated during seed processing, are currently underutilized. This study aimed to explore the valorization potential of this by-product by extracting H. annuus receptacles total polysaccharides (HRTP) and characterizing their potential as natural ingredients in ultraviolet (UV)-protective cosmetics. A new purified polysaccharide named H. annuus receptacles polysaccharide-1 (HRP-1) was isolated, likely exhibiting a backbone of alternating →4)-α-D-GalA-(1→ and →4)-α-D-GalA(6-OCH3)-(1→ units, with a weight-average molecular weight (Mw) of 163 kDa. HRTP demonstrated significant protective effects against UV-induced damage in human immortalized keratinocyte (HaCaT) cells by suppressing intracellular reactive oxygen species (ROS) levels and downregulating MAPK-p38/ERK/JNK pathways, thereby inhibiting inflammatory cytokines (IL-1β, IL-6, IL-8, and TNF-α) and matrix metalloproteinases (MMP-1, MMP-3, and MMP-9). Additionally, HRTP exhibited moisturizing properties. These findings highlight H. annuus receptacle polysaccharides as sustainable, bioactive ingredients for eco-friendly sunscreen formulations, providing a practical approach to converting agricultural by-products into high-value industrial biomaterials. Full article
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13 pages, 1832 KiB  
Article
Novel Resting Energy Expenditure Prediction Equations for Multi-Ethnic Asian Older Adults with Multimorbidity
by Pei San Kua, Musfirah Albakri, Su Mei Tay, Phoebe Si-En Thong, Olivia Jiawen Xia, Wendelynn Hui Ping Chua, Kevin Chong, Nicholas Wei Kiat Tan, Xin Hui Loh, Jia Hui Tan and Lian Leng Low
Nutrients 2025, 17(13), 2144; https://doi.org/10.3390/nu17132144 - 27 Jun 2025
Viewed by 665
Abstract
Background/Objectives: Malnutrition is prevalent among hospitalized older adults with multimorbidity, leading to adverse health outcomes and increased healthcare costs. An accurate assessment of resting energy expenditure (REE) is crucial because an inaccurate estimation of energy needs may result in unintentional underfeeding or overfeeding, [...] Read more.
Background/Objectives: Malnutrition is prevalent among hospitalized older adults with multimorbidity, leading to adverse health outcomes and increased healthcare costs. An accurate assessment of resting energy expenditure (REE) is crucial because an inaccurate estimation of energy needs may result in unintentional underfeeding or overfeeding, both of which can worsen nutritional status and clinical outcomes. While indirect calorimetry (IC) is the preferred method, its clinical applicability is limited. Prediction equations are commonly used, but their accuracy in older Asian patients with multimorbidity remains unclear. Methods: This multicenter, cross-sectional study enrolled 400 patients aged ≥65 years from March to December 2023 in Outram Community Hospital (OCH) and Sengkang Community Hospital (SKCH). Participants’ REE was measured using indirect calorimetry. We compared the performance of the newly developed novel prediction equations (PEs), derived from readily accessible or easily measured anthropometric data, against established equations. Statistical analysis included the calculation of R2, the root mean square error (RMSE), and the intraclass correlation coefficient (ICC) to assess reliability and goodness of fit. Results: A high prevalence (85%) of multimorbidity was observed among the participants. REE increased progressively with body mass index (BMI) across all groups (865.6–1269.4 kcal in females; 889.1–1269.4 kcal in males). The novel PEs (RMSE: 186–191; ICC: 0.5–0.52) demonstrated improved accuracy and stronger reliability compared to conventional equations (RMSE: 222–258; ICC: 0.271–0.460). Conclusions: Our newly developed PEs offer potentially valuable tools for precise REE estimation in hospitalized older Asian patients with multimorbidity. Further external validation and investigation in diverse populations are necessary to confirm these results. Full article
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12 pages, 2201 KiB  
Article
Searching for Paralytic Toxin, Tetrodotoxin, in Swedish Bivalve Shellfish
by Aida Zuberovic Muratovic, Shyamraj Dharavath, Jonas Bergquist, Malin Persson, Elin Renborg, Heidi Pekar and Mirjam Klijnstra
Mar. Drugs 2025, 23(6), 257; https://doi.org/10.3390/md23060257 - 19 Jun 2025
Viewed by 476
Abstract
Tetrodotoxin (TTX), earlier known as a tropical paralytic neurotoxin from pufferfish poisoning, has increasingly been occurring in edible marine species, including filter-feeding bivalves, from relatively cold marine waters of some European countries. The defined conditions that promote the production of TTX, its origin [...] Read more.
Tetrodotoxin (TTX), earlier known as a tropical paralytic neurotoxin from pufferfish poisoning, has increasingly been occurring in edible marine species, including filter-feeding bivalves, from relatively cold marine waters of some European countries. The defined conditions that promote the production of TTX, its origin or the processes of its accumulation in seafood are still not clarified. Recent studies in temperate waters show, however, that the accumulation of quantifiable levels of TTX in bivalves appears to be influenced by seawater temperature (>15 °C), which indicates a seasonal occurrence at these latitudes. Uncertainties still remain regarding how seawater temperature interacts with other climate and environmental factors or organisms in the marine ecosystem to result in detectable levels of TTX in shellfish. Knowledge of the occurrence and distribution of TTX in the marine environment where the edible bivalves grow is important for maintaining seafood safety, as the toxin is heat-stable and remains potent even after cooking. Therefore, in this study, 264 bivalve samples collected in 2019 and 2021 from 17 sites along the Swedish west coast were analyzed with LC-MS/MS to search for TTX. The study explores the hypothesis of TTX presence in Swedish marine waters, outlines the sample screening strategy and objectives, and reports no evidence of TTX presence in Swedish bivalve shellfish (≥7.8 µg/kg) based on the analyzed samples and the time periods in which the studied samples were collected. Full article
(This article belongs to the Special Issue Cyanobacterial Toxins 2025)
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12 pages, 1752 KiB  
Article
The Role of Topological Parameters in Wavelength Requirements for Survivable Optical Backbone Networks
by Filipe Carmo and João Pires
Network 2025, 5(2), 18; https://doi.org/10.3390/network5020018 - 4 Jun 2025
Viewed by 336
Abstract
As optical networks operate using light-based transmission, assigning wavelengths to the paths taken by traffic demands is a key aspect of their design. This paper revisits the wavelength assignment problem in optical backbone networks, focusing on survivability via 1 + 1 Optical Chanel [...] Read more.
As optical networks operate using light-based transmission, assigning wavelengths to the paths taken by traffic demands is a key aspect of their design. This paper revisits the wavelength assignment problem in optical backbone networks, focusing on survivability via 1 + 1 Optical Chanel (OCh) protection, which ensures fault tolerance by duplicating data over two disjoint optical paths. The analysis gives great emphasis to studying the influence of topological parameters on wavelength requirements, with algebraic connectivity being identified as the most significant parameter. The results show that, across a set of 27 real-world networks, the wavelength increment factor, defined as the ratio between the number of wavelengths required with protection and without protection, ranges from 1.49 to 3.07, with a mean value of 2.26. Using synthetic data, formulas were derived to estimate this factor from network parameters, resulting in a mean relative error of 12.7% and errors below 15% in 70% of the real-world cases studied. Full article
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11 pages, 567 KiB  
Review
Are There Unique Barriers and Opportunities for Access to Endoscopic Spine Surgery in Low-Income Countries? A Narrative Review
by Adham M. Khalafallah, Sara Diez, Long Di, Saqib Hasan, Sanjay Konakondla, Osama N. Kashlan, Peter Derman, Mark Mahan, Raymond J. Gardocki, Albert Telfeian, Christoph P. Hofstetter and Gregory Basil
J. Clin. Med. 2025, 14(11), 3876; https://doi.org/10.3390/jcm14113876 - 30 May 2025
Viewed by 625
Abstract
Full endoscopic spine surgery (FESS) offers an ultra-minimally invasive solution for addressing many different degenerative spine pathologies. While FESS has demonstrated strong evidence for faster recovery, reduced hospital stays, fewer complications, and potentially lower overall costs, FESS remains underutilized in low-income countries (LICs). [...] Read more.
Full endoscopic spine surgery (FESS) offers an ultra-minimally invasive solution for addressing many different degenerative spine pathologies. While FESS has demonstrated strong evidence for faster recovery, reduced hospital stays, fewer complications, and potentially lower overall costs, FESS remains underutilized in low-income countries (LICs). This narrative review synthesizes the existing literature to evaluate access to FESS in LICs, highlighting challenges such as a lack of trained neurosurgeons and orthopedic surgeons, insufficient access to specialized equipment, capital costs, and limited representation in research. A systematic literature search identified only a handful of relevant studies, underscoring the scarcity of data on FESS in LICs. Findings reveal stark disparities in training opportunities and equipment availability, with less than 25% of LIC facilities equipped with the essential tools. This review advocates for international collaboration, increased funding, cost reduction, and targeted research to bridge these gaps. Innovative solutions such as virtual training platforms may help overcome current limitations. Addressing these challenges is essential to leveraging FESS’s potential to mitigate the burden of spinal disorders in LICs and advance global health equity. Full article
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19 pages, 3850 KiB  
Article
Effects of Salinity Stress on Grasspea (Lathyrus sativus L.) and Its Wild Relatives: Morpho-Physiological Insights at the Seedling Stage
by Khawla Aloui, Outmane Bouhlal, Hasnae Choukri, Priyanka Gupta, Keltoum El Bouhmadi, Noureddine El Haddad, Khadija El Bargui, Fouad Maalouf and Shiv Kumar
Plants 2025, 14(11), 1666; https://doi.org/10.3390/plants14111666 - 30 May 2025
Viewed by 528
Abstract
Salinity is a critical abiotic stress influencing plant growth. However, its effect on grasspea (Lathyrus sativus L.) remains insufficiently explored. The present study screened 24 germplasm accessions representing 11 Lathyrus species at the seedling stage at 0, 100, and 150 mM NaCl [...] Read more.
Salinity is a critical abiotic stress influencing plant growth. However, its effect on grasspea (Lathyrus sativus L.) remains insufficiently explored. The present study screened 24 germplasm accessions representing 11 Lathyrus species at the seedling stage at 0, 100, and 150 mM NaCl concentrations using a hydroponic system. Our findings indicated that salt stress had a significant effect on all assessed traits, including a reduction in relative leaf water content and SPAD index, a decline in the length and biomass of shoots and roots, and an elevation in their corresponding dry contents. The grasspea accessions displayed a wide range of responses to salt stress. This variation allowed the identification of nine tolerant accessions at both stress levels, belonging to cultivated and wild relative species, specifically LAT 495, IG 65117, L.OCH, IG 65273, IG 64931, IG 114526, IG 64892, IG 66065, and IG 65018. Four accessions, namely IG 110632, IG 114531, IG 65133, and IG 66026, demonstrated tolerance only at 100 mM NaCl concentration. Through identifying these promising accessions, our research offers crucial insights for the initial screening of tolerant genotypes in grasspea, setting the stage for further studies to decipher the intricate mechanisms of salinity tolerance in these accessions. Full article
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18 pages, 4886 KiB  
Article
Kinetics of Different Substituted Phenolic Compounds’ Aqueous OH Oxidation in Atmosphere
by Dandan Hu, Zixuan Wang, Eleonora Aruffo, Xuanli Dai, Zhuzi Zhao and Zhaolian Ye
Atmosphere 2025, 16(5), 567; https://doi.org/10.3390/atmos16050567 - 9 May 2025
Cited by 1 | Viewed by 970
Abstract
Atmospheric aqueous-phase reactions have been recognized as an important source of secondary organic aerosols (SOAs). However, the unclear reaction kinetics and mechanics hinder the in-depth understanding of the SOA sources and formation processes. This study selected ten different substituted phenolic compounds (termed as [...] Read more.
Atmospheric aqueous-phase reactions have been recognized as an important source of secondary organic aerosols (SOAs). However, the unclear reaction kinetics and mechanics hinder the in-depth understanding of the SOA sources and formation processes. This study selected ten different substituted phenolic compounds (termed as PhCs) emitted from biomass burning as precursors, to investigate the kinetics using OH oxidation reactions under simulated sunlight. The factors influencing reaction rates were examined, and the contribution of reactive oxygen species (ROS) was evaluated through quenching and kinetic analysis experiments. The results showed that the pseudo-first-order rate constants (kobs) for the OH oxidation of phenolic compounds ranged from 1.03 × 10−4 to 7.85 × 10−4 s−1 under simulated sunlight irradiation with an initial H2O2 concentration of 3 mM. Precursors with electron-donating groups (-OH, -OCH3, -CH3, etc.) exhibited higher electrophilic radical reactivity due to the enhanced electron density of the benzene ring, leading to higher reaction rates than those with electron-withdrawing groups (-NO2, -CHO, -COOH). At pH 2, the second-order reaction rate (kPhCs, OH) was lower than at pH 5. However, the kobs did not show dependence on pH. The presence of O2 facilitated substituted phenols’ photodecay. Inorganic salts and transition metal ions exhibited varying effects on reaction rates. Specifically, NO3 and Cu2+ promoted kPhCs, OH, Cl significantly enhanced the reaction at pH 2, while SO42− inhibited the reaction. The kPhCs, OH were determined to be in the range of 109~1010 L mol−1 s−1 via the bimolecular rate method, and a modest relationship with their oxidation potential was found. Additionally, multiple substituents can suppress the reactivity of phenolic compounds toward •OH based on Hammett plots. Quenching experiments revealed that •OH played a dominant role in phenolic compound degradation (exceeding 65%). Electron paramagnetic resonance confirmed the generation of singlet oxygen (1O2) in the system, and probe-based quantification further explored the concentrations of •OH and 1O2 in the system. Based on reaction rates and concentrations, the atmospheric aqueous-phase lifetimes of phenolic compounds were estimated, providing valuable insights for expanding atmospheric kinetic databases and understanding the chemical transformation and persistence of phenolic substances in the atmosphere. Full article
(This article belongs to the Special Issue Coordinated Control of PM2.5 and O3 and Its Impacts in China)
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18 pages, 4611 KiB  
Essay
Study of the Effect of Alkali Metal Ions (Li+, Na+, K+) in Inhibiting the Spontaneous Combustion of Coal
by Yunqiu Liu, Hongjie Peng, Ran Peng and Chuanbo Cui
Fuels 2025, 6(2), 31; https://doi.org/10.3390/fuels6020031 - 28 Apr 2025
Viewed by 479
Abstract
The essence of coal spontaneous combustion lies in the existence of a large number of chemically active functional groups in the coal molecule, such as aldehyde group (-CHO) and methoxy group (-OCH3) in the side chain structure of coal molecule, which [...] Read more.
The essence of coal spontaneous combustion lies in the existence of a large number of chemically active functional groups in the coal molecule, such as aldehyde group (-CHO) and methoxy group (-OCH3) in the side chain structure of coal molecule, which can be easily oxidized, thus triggering the spontaneous combustion process. Retardant is a more widely used technology to prevent the spontaneous combustion of coal, but the research on the microscopic level of the mechanism of coal spontaneous combustion retardation has been weak for many years, so deepening the exploration in this field is crucial for the optimization of the retardation strategy. The inhibition effect of Li+, Na+, and K+ inhibitors was investigated through the programmed warming experiments, and the results showed that the carbon monoxide production and oxygen consumption of coal samples inhibited by Li+, Na+, and K+ inhibitors were reduced to different degrees compared with that of the original coal, which proved that it had an inhibitory effect on the spontaneous combustion of coal. In order to deeply investigate the interaction between the molecular structure properties of coal and alkali metal ions, the complexes formed by three typical alkali metal ions-Li+, Na+, and K+-with specific reactive groups (-CHO and -OCH3) in coal were investigated with the help of the quantum chemical calculation software Gaussian 16W, and the following conclusions were made after analyzing the complexes: on the one hand, the complexes formed by Li+, Na+, and K+ with the reactive groups in coal can occupy the sites where the reactive groups bind with oxygen, reduce the chance of coal oxygen contact and inhibit its oxidation process; on the other hand, the coordinating action of alkali metal ions increases the maximum energy barrier that needs to be overcome for the reaction of the originally active groups, resulting in the coal molecules in the process of oxidation reaction, increasing the difficulty of the reaction, thus effectively curbing the tendency of spontaneous combustion of coal. Full article
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18 pages, 1541 KiB  
Article
Stability and Efficacy of Mucoadhesive Eye Drops Containing Olopatadine HCl: Physicochemical, Functional, and Preclinical In Vivo Assessment
by Anđelka Račić, Veljko Krstonošić, Ana Micov, Uroš Pecikoza, Vladimir Dobričić, Erna Turković and Danina Krajišnik
Pharmaceutics 2025, 17(4), 517; https://doi.org/10.3390/pharmaceutics17040517 - 15 Apr 2025
Viewed by 1172
Abstract
Background: The incorporation of polymers into drug delivery vehicles has been shown to be an effective strategy to prolong the residence time of active ingredients in the precorneal tear film and to increase ocular bioavailability. Objectives: The aim of this study was to [...] Read more.
Background: The incorporation of polymers into drug delivery vehicles has been shown to be an effective strategy to prolong the residence time of active ingredients in the precorneal tear film and to increase ocular bioavailability. Objectives: The aim of this study was to develop novel, viscous eye drops containing olopatadine (OCH) as the active ingredient, polysaccharides hydroxypropyl guar gum (HPG), and sodium hyaluronate (SH), individually, and in combination as functional polymers. Methods: Viscous eye drops containing 0.1% OCH in combination with HPG (0.25%) and SH (0.4%), were prepared and evaluated for their physicochemical properties, rheological behavior, mucoadhesion, and preliminary stability. A novel rheological method was used to evaluate the resistance of the eye drops under simulated blinking conditions. In vivo efficacy was evaluated using an ocular itch test in mice to compare the formulations with a commercial product. Results: The formulations remained stable and transparent, with physicochemical parameters within acceptable ranges. Rheological studies confirmed pseudoplastic flow, with the HPG-SH combination exhibiting enhanced viscosity and shear-thinning properties for prolonged retention in the eye. Mucoadhesion was highest in SH-HPG formulations. During simulated blinking cycles, eye drops containing a combination of SH and HPG polymers fully regained their initial viscosity during the resting periods. Preliminary stability studies indicate that the formulated eye drops exhibit satisfactory physicochemical stability under various storage conditions. In vivo, OCH-SH and OCH-HPG-SH drops provided prolonged antipruritic and analgesic effects compared to the reference product. Conclusions: Polysaccharide-based innovative formulations improve OCH retention, enhancing therapeutic efficacy and patient compliance in the treatment of allergic conjunctivitis. Full article
(This article belongs to the Special Issue Biomedical Applications: Advances in Bioengineering and Drug Delivery)
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17 pages, 3303 KiB  
Article
Lanthanoid Coordination Polymers Based on Homoditopic Picolinate Ligands: Synthesis, Structure and Magnetic Properties
by Verónica Jornet-Mollá, Carlos J. Gómez-García, Miquel J. Dolz-Lozano and Francisco M. Romero
Magnetochemistry 2025, 11(4), 31; https://doi.org/10.3390/magnetochemistry11040031 - 7 Apr 2025
Cited by 1 | Viewed by 1146
Abstract
A ditopic ligand (H2L1), containing picolinate subunits segmented by ethynylene bridges, has been used in the synthesis of a series of isostructural coordination polymers, formulated as [(CH3)2NH2][Ln(L1)2]·H2 [...] Read more.
A ditopic ligand (H2L1), containing picolinate subunits segmented by ethynylene bridges, has been used in the synthesis of a series of isostructural coordination polymers, formulated as [(CH3)2NH2][Ln(L1)2]·H2O·CH3COOH, where Ln = Eu (1), Gd (2), Tb (3), Dy (4) and Ho (5). The single-crystal structures show that these compounds crystallise in the orthorhombic Pna21 space group and form 3D anionic lattices with triangular cavities. AC magnetic susceptibility measurements show that the Gd, Tb and Dy derivatives (24) present a slow relaxation in their magnetisation under an applied DC magnetic field. The detailed study of the AC susceptibility in compounds 2 and 4 shows that they relax following direct and Orbach mechanisms under these conditions. The Dy derivative (4) retains this behaviour in the absence of an external field, relaxing via quantum tunnelling and Orbach mechanisms. Compound 2 is one of the very few reported Gd(III) compounds showing slow relaxation in its magnetisation. Full article
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16 pages, 2719 KiB  
Article
Methoxylated Chrysin and Quercetin as Potent Stimulators of Melanogenesis
by Pattara Poungcho, Rita Hairani, Chatchai Chaotham, Wanchai De-Eknamkul and Warinthorn Chavasiri
Int. J. Mol. Sci. 2025, 26(7), 3281; https://doi.org/10.3390/ijms26073281 - 1 Apr 2025
Cited by 1 | Viewed by 641
Abstract
Polymethoxyflavonoids (PMFs) from plants are known to exhibit melanogenic activity. Very little is known about their structure-activity relationships, and this was the aim of this study. Several series of alkoxy flavonoids were synthesized via semisynthetic and total synthetic pathways. Their structures were identified [...] Read more.
Polymethoxyflavonoids (PMFs) from plants are known to exhibit melanogenic activity. Very little is known about their structure-activity relationships, and this was the aim of this study. Several series of alkoxy flavonoids were synthesized via semisynthetic and total synthetic pathways. Their structures were identified by NMR analyses, followed by evaluating their potency on the stimulation of melanogenesis using mouse B16F10 and human MNT-1 cells. Among more than twenty methoxylated flavonoids, 5,7-dimethoxychrysin (dimethoxylated chrysin, F1) and 3,3′,4′,5,7-pentamethoxyquercetin (pentamethoxylated quercetin, F21) appeared to be the most active melanogenic-stimulating compounds in a dose-dependent manner. Both compounds showed no effect on cell viability as determined by MTT assay. The structure-activity relationship study of PMFs revealed that the -OCH3 substituent at 5 and 7 positions of A-ring are the most important as melanogenic-stimulating part (e.g., 5,7-dimethoxychrysin, F1) followed by at 3′ and 4′ positions of B-ring, and at 3 positions of C-ring (e.g., 3,3′,4′,5,7-pentamethoxyquercetin, F21), Therefore, both natural methoxylated flavonoid derivatives of chrysin and quercetin have a potential to be developed further as melanogenic stimulators. Full article
(This article belongs to the Special Issue Research Progress of Metabolomics in Health and Disease)
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14 pages, 5324 KiB  
Article
Electrocatalytic CO2 Reduction Coupled with Water Oxidation by bi- and Tetranuclear Copper Complexes Based on di-2-pyridyl Ketone Ligand
by Siyuan Yang, Tian Liu, Wenbo Huang, Chengwen Zhang and Mei Wang
Molecules 2025, 30(7), 1544; https://doi.org/10.3390/molecules30071544 - 31 Mar 2025
Viewed by 635
Abstract
In the field of sustainable energy conversion and storage technologies, copper-based complexes have become a research hotspot due to their efficient and stable catalytic performance. The development of bifunctional catalysts that can simplify catalytic steps, enhance efficiency, and reduce catalyst usage has become [...] Read more.
In the field of sustainable energy conversion and storage technologies, copper-based complexes have become a research hotspot due to their efficient and stable catalytic performance. The development of bifunctional catalysts that can simplify catalytic steps, enhance efficiency, and reduce catalyst usage has become an important research area. In this study, we successfully synthesized two copper complexes with different geometries utilizing di(2-pyridyl) ketone as the ligand, [CuII2L2Cl2]·0.5H2O (1) and [Cu4IIL4(OCH3)2](NO3)2 (2) (L = deprotonated methoxy-di-pyridin-2-yl-methanol), which can serve as homogeneous electrocatalysts for water oxidation and CO2 reduction simultaneously. The turnover frequency (TOF) of complexes 1 and 2 for electrocatalytic water oxidation are 7.23 s−1 and 0.31 s−1 under almost neutral condition (pH = 8.22), respectively. Meanwhile, the TOF of complexes 1 and 2 for the catalytic reduction of CO2 to CO are 4.27 s−1 and 8.9 s−1, respectively. In addition, both complexes remain essentially unchanged during the electrocatalytic water oxidation and electrocatalytic CO2 reduction processes, demonstrating good stability. Structural analysis reveals that the distinct catalytic efficiencies originate from their geometric configurations: the binuclear structure of complex 1 facilitates proton-coupled electron transfer during water oxidation, whereas the tetranuclear architecture of complex 2 enhances CO2 activation. Complexes 1 and 2 represent the first two copper molecular electrocatalysts capable of catalyzing both water oxidation and CO2 reduction. The findings in this work can open up new avenues for the advancement of artificial photosynthesis simulation and the development of bifunctional catalysts for water oxidation and CO2 reduction. Full article
(This article belongs to the Special Issue Design, Synthesis, and Catalytic Applications of Metal Complexes)
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35 pages, 7317 KiB  
Article
Fluorescent Probes to Image the KCa3.1 Channel in Tumor Cells
by Insa Thale, Elke Naß, Laura Vinnenberg, Luca Matteo Todesca, Thomas Budde, Ivan Maisuls, Cristian A. Strassert, Albrecht Schwab and Bernhard Wünsch
Pharmaceutics 2025, 17(2), 154; https://doi.org/10.3390/pharmaceutics17020154 - 23 Jan 2025
Viewed by 1019
Abstract
Background/Objectives: The Ca2+-activated K+ channel KCa3.1 is not only involved in physiological processes such as immune reactions and control of vascular tone, but is highly expressed in various tumor entities. Thus, imaging of KCa3.1 channels [...] Read more.
Background/Objectives: The Ca2+-activated K+ channel KCa3.1 is not only involved in physiological processes such as immune reactions and control of vascular tone, but is highly expressed in various tumor entities. Thus, imaging of KCa3.1 channels comes into focus for the localization of high channel density, i.e., for tumor diagnosis. In particular, the physicochemical properties of the fluorescent probes should be improved compared to existing probes. Methods: The small molecule inhibitor of the KCa3.1 channel, senicapoc, was used as a warhead and was coupled with different fluorescent dyes. After synthesis of the novel probes, their physicochemical properties (lipophilicity, photophysical properties) and their ability to image KCa3.1 channels in A549-3R lung tumor cells were determined. Results: In order to increase the polarity and quantum yield of reported fluorescent probes, three strategies were followed: (1) An F-atom at the B-atom of bodipy-labeled senicapoc derivatives 9a, 9b, and 15a was replaced by a OCH3 moiety, which decreased the logP value by one log-unit. (2) The p-phenylene moiety of the linker was replaced by an aliphatic tetramethylene linker decreasing the lipophilicity by 0.3–0.5 log-units. (3) Instead of bodipy dyes, fluorescein was coupled with the senicapoc warhead resulting in very polar probes 21a and 21b with low logP values of 1.5 and 1.3, respectively. Introduction of an ethyl moiety at the bodipy core increased the quantum yield, which resulted in the best punctate staining pattern of fixed and living A549-3R lung tumor cells with the ethylbodipy-labeled senicapoc derivative 10b. The specificity was shown by various control experiments. Co-staining with 10b and an antibody did not result in overlapping signals. Conclusions: The well-balanced lipophilicity and fluorescent quantum yield render the ethylbodipy-labeled senicapoc derivative 10b a very good probe to image selectively KCa3.1 ion channels in fixed and living tumor cells. It was hypothesized that the antibody binds selectively at the closed channel (58.5%), whereas the senicapoc–bodipy conjugate 10b binds selectively at the open channel (41.5%). The ratio 58.5:41.5 reflects the ratio of the ion channel in closed and open conformations. Full article
(This article belongs to the Special Issue Fluorescent Probes as a Tool in Diagnostic and Drug Delivery)
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12 pages, 3420 KiB  
Article
Implementation and Feasibility of Mechanomyography in Minimally Invasive Spine Surgery
by Fabian Sommer, Ibrahim Hussain, Noah Willett, Mousa K. Hamad, Chibuikem A. Ikwuegbuenyi, Rodrigo Navarro-Ramirez, Sertac Kirnaz, Lynn McGrath, Jacob Goldberg, Amanda Ng, Catherine Mykolajtchuk, Sam Haber, Vincent Sullivan, Pravesh S. Gadjradj and Roger Härtl
J. Pers. Med. 2025, 15(2), 42; https://doi.org/10.3390/jpm15020042 - 23 Jan 2025
Cited by 2 | Viewed by 1341
Abstract
Background: Mechanomyography (MMG) is a neurodiagnostic technique with a documented ability to evaluate the compression of nerve roots. Its utility in degenerative spine surgery is unknown. Objective: To assess the utility of intraoperative MMG during cervical posterior foraminotomy, minimally invasive transforaminal [...] Read more.
Background: Mechanomyography (MMG) is a neurodiagnostic technique with a documented ability to evaluate the compression of nerve roots. Its utility in degenerative spine surgery is unknown. Objective: To assess the utility of intraoperative MMG during cervical posterior foraminotomy, minimally invasive transforaminal interbody fusion (MIS-TLIF), and tubular lumbar far lateral discectomy. Methods: A prospective feasibility study was conducted during which MMG was applied during three procedures. Adhesive accelerometers were placed on two muscle groups per procedure. Stimulus threshold in mA was recorded before and after the decompression of the nerve root. Differences in stimulation thresholds were correlated with operative findings. Results: In total, 22 patients were included in this study; 5 patients underwent cervical foraminotomies, 3 underwent MIS-TLIFs, and 14 underwent tubular far lateral discectomies. For the foraminotomies, all cases showed a reduction in stimulation threshold (mean of 3.4 mA) after decompression. For MIS-TLIF cases, there was a limited reduction in the stimulation threshold after decompression (mean 1.7 mA). For far lateral discectomy, there was a mean reduction of 4.3 mA in the stimulation threshold following decompression. Conclusions: MMG is a method that may provide intraoperative feedback on the decompression of nerve roots. In the context of MIS-TLIF, MMG showed a limited decrease in stimulus threshold. This may be due to the identification of the nerve occurring after decompression is already underway. For cervical foraminotomies and far lateral discectomies, MMG showed promising results in determining adequate decompression of the nerve root. Full article
(This article belongs to the Special Issue Clinical Research of Minimally Invasive Spine Surgery)
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