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14 pages, 641 KiB

Open AccessArticle

The Role of Social Media and Artificial Intelligence (AI) in Enhancing Digital Marketing Resilience During Crises

by Bora Gündüzyeli

Sustainability 2025, 17(7), 3134; https://doi.org/10.3390/su17073134 (registering DOI) - 2 Apr 2025

In an increasingly interconnected world, businesses may face the challenge of managing crises, whether they are economic downturns, natural disasters, or global pandemics. During such times, building strong and sustainable marketing resilience becomes crucial for businesses aiming to survive and thrive. Digital technologies—particularly [...] Read more.

In an increasingly interconnected world, businesses may face the challenge of managing crises, whether they are economic downturns, natural disasters, or global pandemics. During such times, building strong and sustainable marketing resilience becomes crucial for businesses aiming to survive and thrive. Digital technologies—particularly social media platforms and artificial intelligence (AI)—can play a vital role in enhancing marketing resilience. This research seeks to answer the core question: “How can social media and AI technologies help businesses build marketing resilience during crises”? Drawing from a literature review, this study analyzes a wide range of relevant research. The findings indicate that AI and social media together contribute to enhancing marketing resilience during crises by enabling real-time engagement, data-driven decision-making, and personalized communication. However, these technologies also present challenges, such as privacy concerns, algorithmic bias, and potential risks to brand reputation. This research contributes to the field by analyzing how AI and social media technologies enable companies to remain agile, reduce the impact of crises, and maintain sustainability objectives in their marketing practices. Full article

(This article belongs to the Special Issue Building Resilience and Sustainable Societies: The Intersection of Digital Technologies, Cyber Resilience, and Sustainable Development)

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14 pages, 896 KiB

Open AccessArticle

Assessing First and Multiple Reoperations in 23,301 Breast Reconstructions: Immediate Versus Delayed Reconstructions in Women with Breast Cancer

by Kathryn E. Royse, Tina M. Smith, Cissy M. Tan, Eric Y. Lin, Robert G. Neumann, Jessica E. Harris, Elizabeth W. Paxton and Winnie M. Tong

Onco 2025, 5(2), 15; https://doi.org/10.3390/onco5020015 (registering DOI) - 2 Apr 2025

Abstract

Background: Few studies have compared the risk of reoperation by timing in breast reconstruction surgery after mastectomy. We evaluated the first and total number of reoperations by reconstruction timing in women with breast cancer undergoing primary mastectomy. Methods: A cohort study of 23,301 [...] Read more.

Background: Few studies have compared the risk of reoperation by timing in breast reconstruction surgery after mastectomy. We evaluated the first and total number of reoperations by reconstruction timing in women with breast cancer undergoing primary mastectomy. Methods: A cohort study of 23,301 primary mastectomies in women with breast cancer undergoing either immediate breast reconstruction (IBR) or delayed reconstruction was carried out within Kaiser Permanente between 2010 and 2022. The first reoperation rate was calculated using cause-specific Cox Proportional Hazards Models, while Multiplicative Cox Proportional Hazards Models were used to account for mortality and timing in reoperation. Patients were continuously monitored for death, outcome of interest, loss to follow-up through healthcare membership termination, or study end date (31 December 2022). Results: In total, 78.4% (n = 18,276) of the cohort underwent IBR. The average follow-up time was 5.9 years (±3.8). The following covariates were imbalanced (standardized mean difference [SMD] ≥ 0.20) between IBR and delayed groups: BMI, smoking status, year of mastectomy, bilateral procedures, and reconstruction type. The crude incidence of first reoperation was 33.04% vs. 31.72% in IBR vs. delayed patients and the risk of reoperation was 18% higher in IBR patients (HR = 1.18, 95% CI = 1.12–1.25). There was no difference in the risk of reoperation by timing (p > 0.05) when assessing multiple reoperations. The reoperation risk was the highest for IBR patients who did not complete reconstruction or single-stage reconstruction. In addition, the first reoperation rate of IBR patients was higher in those who underwent expander–implant-based reconstruction. Conclusions: The first reoperation rate was higher in IBR patients compared to those who delayed reconstruction, although we failed to detect a difference for multiple returns to surgery, except in certain subgroups. Assessing reoperation risk by timing among different reconstruction modalities can aid patients in making informed decisions about the type of breast reconstruction to undergo. Full article

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11 pages, 235 KiB

Open AccessCommunication

Talking Resilience: Embedded Natural Language Cyber-Organizations by Design

by Andrea Tomassi, Andrea Falegnami and Elpidio Romano

Systems 2025, 13(4), 247; https://doi.org/10.3390/systems13040247 (registering DOI) - 2 Apr 2025

Abstract

This communication examines the interplay between linguistic mediation and knowledge conversion in cyber-sociotechnical systems (CSTSs) via the WAx framework, which outlines various work representations and eight key conversion activities. Grounded in enactivist principles, we argue that language is a dynamic mechanism that shapes, [...] Read more.

This communication examines the interplay between linguistic mediation and knowledge conversion in cyber-sociotechnical systems (CSTSs) via the WAx framework, which outlines various work representations and eight key conversion activities. Grounded in enactivist principles, we argue that language is a dynamic mechanism that shapes, and is shaped by, human–machine interactions, enhancing system resilience and adaptability. By integrating the concepts of simplexity, complixity, and complexity compression, we illustrate how complex cognitive and operational processes can be selectively condensed into efficient outcomes. A case study of a chatbot-based customer support system demonstrates how the phases of socialization, introspection, externalization, combination, internalization, conceptualization, reification, and influence collaboratively drive the evolution of resilient CSTS designs. Our findings indicate that natural language serves as a bridging tool for effective sense-making, adaptive coordination, and continuous learning, offering novel insights into designing technologically advanced, socially grounded, and evolving sociotechnical systems. Full article

(This article belongs to the Special Issue Cognitive and Practical Perspectives on Resilience, Organization and Entangled Systems)

25 pages, 1505 KiB

Open AccessArticle

Customer-Directed Counterproductive Work Behavior of Gig Workers in Crowdsourced Delivery: A Perspective on Customer Injustice

by Yanfeng Liu, Lanhui Cai, Xueqin Wang and Xueli Tan

Systems 2025, 13(4), 246; https://doi.org/10.3390/systems13040246 (registering DOI) - 2 Apr 2025

Abstract

In the platform economy, customers are the primary interaction partners of gig workers, and their behaviors and attitudes significantly influence gig workers’ work experiences and behavioral responses. Based on the stressor–emotion model and social exchange theory, this paper systematically explores the formation mechanism [...] Read more.

In the platform economy, customers are the primary interaction partners of gig workers, and their behaviors and attitudes significantly influence gig workers’ work experiences and behavioral responses. Based on the stressor–emotion model and social exchange theory, this paper systematically explores the formation mechanism of customer-directed counterproductive work behavior. This study employs structural equation modeling to analyze survey data collected from 385 registered gig workers on crowdsourced delivery platforms in China. The results indicate that customer injustice increases gig workers’ negative emotions, perceived organizational injustice, and customer-directed counterproductive work behavior while decreasing customer commitment. Furthermore, negative emotions, perceived organizational injustice, and customer commitment mediate the relationship between customer injustice and customer-directed counterproductive work behavior. Additionally, job demands act as a buffering mechanism in the occurrence of customer-directed counterproductive work behavior. This study is the first to systematically focus on customer-directed counterproductive work behavior among crowdsourced delivery gig workers, enriching the existing literature. The findings provide practical insights for crowdsourced delivery platforms, aiding in understanding gig workers’ work psychology and optimizing labor management strategies. Full article

(This article belongs to the Section Systems Practice in Social Science)

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11 pages, 1066 KiB

Open AccessArticle

Effects of Caffeine on THP-1 Myelogenous Cell Inflammatory Gene Expression

by Zeyar T. Htun, Thomas M. Raffay, Richard J. Martin, Peter M. MacFarlane and Tracey L. Bonfield

Curr. Issues Mol. Biol. 2025, 47(4), 248; https://doi.org/10.3390/cimb47040248 (registering DOI) - 2 Apr 2025

Abstract

Caffeine is administered to preterm infants in neonatal intensive care units for prevention and treatment of apnea of prematurity. Although caffeine’s primary effect is to impact the respiratory drive of preterm infants, caffeine also has anti-inflammatory properties. This study investigated the role of [...] Read more.

Caffeine is administered to preterm infants in neonatal intensive care units for prevention and treatment of apnea of prematurity. Although caffeine’s primary effect is to impact the respiratory drive of preterm infants, caffeine also has anti-inflammatory properties. This study investigated the role of caffeine on the inflammatory gene expression in THP-1 pre-monocytes exposed to lipopolysaccharide (LPS) in vitro, mimicking a clinical pro-inflammatory scenario. The effects of different physiologic dosages of caffeine administration post-LPS (treatment with caffeine) and pre-LPS (prophylaxis with caffeine) on pro-inflammatory gene expressions (TNF-α, NF-κB, IL-8, PPARγ) of the THP-1 cells were investigated. The post-LPS group showed a dose-dependent decrease in TNF-α at a caffeine concentration of 100 μM and NF-κB gene expression at 50 and 100 μM, with the implication that this is an optimal anti-inflammatory caffeine concentration range. Clinically, this would correspond to a serum caffeine level between 10 and 20 μg/mL, respectively. For the pre-LPS group, TNF-α and NF-κB gene expression decreased at all studied caffeine concentrations. These findings point to caffeine’s potential therapeutic capacity in regulating monocyte inflammatory responses to gram-negative infections in addition to regulating neuron response in the brainstem for preterm infants. Full article

(This article belongs to the Special Issue Molecular Mechanisms and Innovative Therapeutic Approaches in Inflammatory Diseases, Pioneering Precision Medicine Solutions)

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15 pages, 2224 KiB

Open AccessArticle

Fe³⁺ and Mn²⁺ Removal from Water Solutions by Clinoptilolite Zeolites as a Potential Treatment for Groundwater Wells

by William D. Arenhardt, Felipe Ketzer, João H. C. Wancura, Janaina Seraglio, Fabio L. Carasek, Guilherme Zin, Jean F. F. Calisto, Clovis A. Rodrigues, Alessandra C. de Meneses, José Vladimir Oliveira and Jacir Dal Magro

Processes 2025, 13(4), 1060; https://doi.org/10.3390/pr13041060 (registering DOI) - 2 Apr 2025

Abstract

This study presents data on the water quality of the Guarani Aquifer based on samples collected from distinct groundwater wells in the western region of Santa Catarina State, Brazil. Among the analyses performed, the results indicated the need for treatment to ensure suitability [...] Read more.

This study presents data on the water quality of the Guarani Aquifer based on samples collected from distinct groundwater wells in the western region of Santa Catarina State, Brazil. Among the analyses performed, the results indicated the need for treatment to ensure suitability for human consumption, particularly concerning Fe³⁺ and Mn²⁺ ions. Accordingly, natural (NCLIN) and activated clinoptilolite (ACLIN) zeolites were evaluated for ion removal from synthetic aqueous solutions through adsorption. NCLIN demonstrated excellent performance in adsorbing Fe³⁺ and Mn²⁺ ions, achieving removal efficiencies of over 98% and 95%, respectively, at a controlled pH of 6.0 (NCLIN) or 4.0 (ACLIN). A non-linear approach to modeling adsorption kinetics indicated that the pseudo-second-order model best represented the experimental data. This finding suggests that the interaction between the adsorbent and Fe³⁺ and Mn²⁺ ions occur through electron sharing and chemisorption. Equilibrium modeling analysis revealed that adsorption on NCLIN occurred in a monolayer, whereas adsorption on ACLIN followed a multilayer pattern. This behavior is attributed to the activation process with H₂SO₄, which led to dealumination and the formation of HSO₃⁻ groups on the adsorbent surface. Full article

(This article belongs to the Special Issue Advances in Wastewater and Solid Waste Treatment Processes)

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26 pages, 3432 KiB

Open AccessArticle

Pristine and Reassembled Nanosheets of Layered Perovskite-like Titanates HLnTiO₄ and H₂Ln₂Ti₃O₁₀ (Ln = La, Nd) as Photocatalysts for Hydrogen Evolution

by Sergei A. Kurnosenko, Oleg I. Silyukov, Ivan A. Rodionov, Iana A. Minich and Irina A. Zvereva

Solids 2025, 6(2), 16; https://doi.org/10.3390/solids6020016 (registering DOI) - 2 Apr 2025

Abstract

Layered Ruddlesden–Popper titanates HLnTiO₄ and H₂Ln₂Ti₃O₁₀ (Ln = La, Nd) have been exfoliated into nanosheets in aqueous tetrabutylammonium hydroxide and systematically investigated as hydrogen evolution photocatalysts. The nanosheets were tested both in as-prepared pristine form [...] Read more.

Layered Ruddlesden–Popper titanates HLnTiO₄ and H₂Ln₂Ti₃O₁₀ (Ln = La, Nd) have been exfoliated into nanosheets in aqueous tetrabutylammonium hydroxide and systematically investigated as hydrogen evolution photocatalysts. The nanosheets were tested both in as-prepared pristine form and after reassembly by two methods (simple filtration and precipitation by hydrochloric acid). The nanosheet-based samples demonstrated by up to 88 times greater photocatalytic performance in comparison with the bulk precursors and, after modification with a Pt cocatalyst, provided apparent quantum efficiency of hydrogen generation up to 14.2% in 1 mol.% aqueous methanol and 3.15% in pure water. It was established that the form in which the nanosheets are used strongly affects the hydrogen production efficiency: the latter typically decreases when moving from the pristine nanosheets to filtered ones and then to those restacked by hydrochloric acid, which is determined by the difference in their physical–chemical characteristics being influenced by the reassembly approach. Full article

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10 pages, 287 KiB

Open AccessReview

Effect of GnRH Analog Therapy on Adult Height in Girls with Idiopathic Central Precocious Puberty

by Reiko Saito and Yukihiro Hasegawa

Endocrines 2025, 6(2), 16; https://doi.org/10.3390/endocrines6020016 (registering DOI) - 2 Apr 2025

Abstract

Precocious puberty (PP) is characterized by the early onset of secondary sexual characteristics and accelerated growth, which often result in compromised adult height (AH). Central precocious puberty (CPP), a subset of PP, is treated with gonadotropin-releasing hormone analogs (GnRHa) to suppress premature hormonal [...] Read more.

Precocious puberty (PP) is characterized by the early onset of secondary sexual characteristics and accelerated growth, which often result in compromised adult height (AH). Central precocious puberty (CPP), a subset of PP, is treated with gonadotropin-releasing hormone analogs (GnRHa) to suppress premature hormonal activation and delay epiphyseal closure, thereby preserving height potential. The present review examined the effects of GnRHa on AH outcomes in girls with idiopathic CPP. Although AH is greater with GnRHa therapy than without it, the treatment does not consistently restore the patient’s genetic potential. The benefits of the treatment are most evident in girls in whom idiopathic CPP is diagnosed before 6 years of age and they achieve a height gain of 4.5–14.1 cm, which is unattainable without treatment. However, the treatment of older children (ages 6–8) shows conflicting results, with the AH outcome varying among previous reports. In particular, slowly progressive CPP is known to have a favorable height prognosis even without treatment. Another factor influencing the AH prognosis is the timing of GnRHa discontinuation; the best time to discontinue GnRHa therapy for the best AH outcome is reportedly the bone age of approximately 12 years. In conclusion, although GnRHa therapy significantly improves the AH, especially in early-onset CPP, its effectiveness is uncertain in borderline or late-onset cases. Further research is required to formulate more precise criteria for patient selection and treatment discontinuation to optimize height outcome in girls with idiopathic CPP. Full article

(This article belongs to the Section Pediatric Endocrinology and Growth Disorders)

19 pages, 897 KiB

Open AccessReview

Orthobiologics Revisited: A Concise Perspective on Regenerative Orthopedics

by Fábio Ramos Costa, Luyddy Pires, Rubens Andrade Martins, Márcia Santos, Gabriel Silva Santos, João Vitor Lana, Bruno Ramos Costa, Napoliane Santos, Alex Pontes de Macedo, André Kruel and José Fábio Lana

Curr. Issues Mol. Biol. 2025, 47(4), 247; https://doi.org/10.3390/cimb47040247 (registering DOI) - 2 Apr 2025

Abstract

At the forefront of regenerative medicine, orthobiologics represent a spectrum of biological substances that offer promising alternatives for tissue repair and regeneration. Traditional surgical treatments often involve significant risks, extended recovery periods, and may not fully restore tissue functionality, creating a strong demand [...] Read more.

At the forefront of regenerative medicine, orthobiologics represent a spectrum of biological substances that offer promising alternatives for tissue repair and regeneration. Traditional surgical treatments often involve significant risks, extended recovery periods, and may not fully restore tissue functionality, creating a strong demand for less invasive options. This paper presents a concise overview of orthobiologics, reexamining their role within the broader landscape of regenerative medicine. Beginning with a brief introduction to orthobiologics, the paper navigates through various types of biological materials and their associated mechanisms of action and clinical applications. By highlighting platelet derivatives, bone marrow-derived products, and processed adipose tissue, among others, it underscores the pivotal role of orthobiologics in prompting biological responses like cellular proliferation, differentiation, and angiogenesis, thereby fostering tissue healing. Furthermore, this paper explores the diverse applications of orthobiologics in orthopedic conditions, outlining their utility in the treatment of bone and soft-tissue injuries. Addressing clinical considerations, it discusses safety profiles, efficacy, patient selection criteria, and emerging challenges. With the limitations of traditional medicine becoming more apparent, orthobiologics offer an innovative and less invasive approach to patient care. Looking forward, this paper approaches future directions in orthobiologics research, emphasizing the need for continued innovation and exploration. Through a concise perspective, this paper aims to provide clinicians, researchers, and stakeholders with a comprehensive understanding of orthobiologics and their evolving role in regenerative medicine. Full article

(This article belongs to the Special Issue The Contribution and Application of Molecular Biology in the Applied Biosciences—Focusing on Medicine, Biomaterials and Tissue Engineering Fields, 2nd Edition)

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13 pages, 2158 KiB

Open AccessArticle

A 12-Week Prospective, Double-Blind, Multicenter, Randomized Study Comparing 100 Units of Abobotulinum Toxin Type A (Dysport^®) and 33.33 Units of Neubotulinum Toxin Type A (Neuronox^®) for the Treatment of Hemifacial Spasm

by Subsai Kongsaengdao, Arkhom Arayawichanont, Kanoksri Samintharapanya, Pichai Rojanapitayakorn, Benchalak Maneeton and Narong Maneeton

Toxins 2025, 17(4), 173; https://doi.org/10.3390/toxins17040173 (registering DOI) - 2 Apr 2025

Abstract

Previous randomized controlled trials (RCTs) investigating Botulinum toxin A (BoNT-A) for treatment of hemifacial spasm (HFS) have primarily focused on symptom relief and quality-of-life improvement. However, head-to-head comparisons of different BoNT-A formulations, particularly in terms of onset, duration of action, and efficacy, remain [...] Read more.

Previous randomized controlled trials (RCTs) investigating Botulinum toxin A (BoNT-A) for treatment of hemifacial spasm (HFS) have primarily focused on symptom relief and quality-of-life improvement. However, head-to-head comparisons of different BoNT-A formulations, particularly in terms of onset, duration of action, and efficacy, remain limited. We conducted a 12-week prospective, randomized controlled trial comparing the efficacy and safety of 33.33 units of Neubotulinum toxin A (Neu-BoNT-A) with 100 units of Abobotulinum toxin A (Abo-BoNT-A) in the treatment of HFS. A total of 87 patients were enrolled between September and December 2024. Neu-BoNT-A and Abo-BoNT-A exhibited similar onset and duration of action [5.0 ± 0.9 vs. 6.2 ± 0.7 days, respectively (p = 0.33)]. After 12 weeks of treatment, Neu-BoNT-A demonstrated superior efficacy in reducing the daily duration of HFS (2.00 ± 0.06 vs. 1.42 ± 0.10 h/day, p < 0.001) and improving sleep duration (1.37 ± 0.01 vs. 1.06 ± 0.01 h/day, p < 0.001). However, Abo-BoNT-A was associated with significantly lower absolute daily disability time compared to Neu-BoNT-A (11.4 vs. 1.2 min/day, p < 0.001). No serious adverse events were observed. Both Neu-BoNT-A and Abo-BoNT-A were safe and effective in treating HFS. However, Neu-BoNT-A was more effective in HFS with minimal symptoms without disability and Abo-BoNT-A more effective in HFS with greater duration of disability. Full article

(This article belongs to the Special Issue Advances in the Treatment of Movement Disorders with Botulinum Toxins)

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18 pages, 3958 KiB

Open AccessArticle

AI-Driven UAV Surveillance for Agricultural Fire Safety

by Akmalbek Abdusalomov, Sabina Umirzakova, Komil Tashev, Nodir Egamberdiev, Guzalxon Belalova, Azizjon Meliboev, Ibragim Atadjanov, Zavqiddin Temirov and Young Im Cho

Fire 2025, 8(4), 142; https://doi.org/10.3390/fire8040142 (registering DOI) - 2 Apr 2025

Abstract

The increasing frequency and severity of agricultural fires pose significant threats to food security, economic stability, and environmental sustainability. Traditional fire-detection methods, relying on satellite imagery and ground-based sensors, often suffer from delayed response times and high false-positive rates, limiting their effectiveness in [...] Read more.

The increasing frequency and severity of agricultural fires pose significant threats to food security, economic stability, and environmental sustainability. Traditional fire-detection methods, relying on satellite imagery and ground-based sensors, often suffer from delayed response times and high false-positive rates, limiting their effectiveness in mitigating fire-related damages. In this study, we propose an advanced deep learning-based fire-detection framework that integrates the Single-Shot MultiBox Detector (SSD) with the computationally efficient MobileNetV2 architecture. This integration enhances real-time fire- and smoke-detection capabilities while maintaining a lightweight and deployable model suitable for Unmanned Aerial Vehicle (UAV)-based agricultural monitoring. The proposed model was trained and evaluated on a custom dataset comprising diverse fire scenarios, including various environmental conditions and fire intensities. Comprehensive experiments and comparative analyses against state-of-the-art object-detection models, such as You Only Look Once (YOLO), Faster Region-based Convolutional Neural Network (Faster R-CNN), and SSD-based variants, demonstrated the superior performance of our model. The results indicate that our approach achieves a mean Average Precision (mAP) of 97.7%, significantly surpassing conventional models while maintaining a detection speed of 45 frames per second (fps) and requiring only 5.0 GFLOPs of computational power. These characteristics make it particularly suitable for deployment in edge-computing environments, such as UAVs and remote agricultural monitoring systems. Full article

(This article belongs to the Special Issue Integrating AI and Remote Sensing for Monitoring and Mapping Fire Impacts on Agroforestry and Wildlife Systems)

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13 pages, 241 KiB

Open AccessArticle

The Prevalence of Oral Anomalies Among Healthy Newborns at a Gynecological Obstetric Hospital in Quito, Ecuador: An Observational, Cross-Sectional Study

by Eleonor Vélez-León, Emilia Guerrero, Mauricio Orlando Carrillo, Marina Cabrera, Gustavo Tello and Patricia Pinos

Dent. J. 2025, 13(4), 158; https://doi.org/10.3390/dj13040158 (registering DOI) - 2 Apr 2025

Abstract

Objectives: Early observations often fail to detect anomalies that may impact the health and quality of life of newborns. This study aimed to determine the prevalence of oral anomalies in newborns and explore their possible associations with sociodemographic factors. Methods: A cross-sectional study [...] Read more.

Objectives: Early observations often fail to detect anomalies that may impact the health and quality of life of newborns. This study aimed to determine the prevalence of oral anomalies in newborns and explore their possible associations with sociodemographic factors. Methods: A cross-sectional study was conducted in Quito, Ecuador, analyzing a sample of 241 newborns. The presence of oral anomalies was recorded, and their association with sex, birth weight, maternal age, and gestational factors was evaluated. Results: The prevalence of oral anomalies was 72.3%, with Epstein’s pearls being the most common (50%). Other findings included Bohn’s nodules and dental lamina cysts, while no cases of natal teeth or congenital epulis were observed. Ankyloglossia was identified in 1.36% of newborns. No significant correlations were found between the presence of oral anomalies and sex, birth weight, maternal age, or gestational factors. Conclusions: The high prevalence (72.3%) of oral anomalies in the studied newborns underscores the importance of early detection and management. Epstein’s pearls were the most frequent anomaly, followed by Bohn’s nodules, dental lamina cysts, and ankyloglossia, while no cases of natal teeth or congenital epulis were identified. No statistically significant associations were found with sex, birth weight, maternal age, or pregnancy complications. These findings emphasize the need for early pediatric dental assessment and an interdisciplinary approach to ensure proper neonatal oral health. Further research is recommended to explore potential causes and interventions to optimize oral health from birth. Full article

(This article belongs to the Special Issue Preventive Dentistry and Dental Public Health)

20 pages, 5173 KiB

Open AccessArticle

Scarf Adhesive Bonding of 3D-Printed Polymer Structures

by Tiago F. R. Ribeiro, Raul D. S. G. Campilho, Ricardo F. R. Pinto and Ricardo J. B. Rocha

J. Manuf. Mater. Process. 2025, 9(4), 115; https://doi.org/10.3390/jmmp9040115 (registering DOI) - 2 Apr 2025

Abstract

Additive manufacturing (AM) has swiftly emerged as a substitute for conventional methods such as machining and injection moulding. Its appeal is attributed to accelerated prototyping, improved sustainability, and the capacity to fabricate intricate shapes. Nonetheless, the size constraints of additive manufacturing components require [...] Read more.

Additive manufacturing (AM) has swiftly emerged as a substitute for conventional methods such as machining and injection moulding. Its appeal is attributed to accelerated prototyping, improved sustainability, and the capacity to fabricate intricate shapes. Nonetheless, the size constraints of additive manufacturing components require the assembly of smaller 3D-printed elements to create larger structures. This study investigates the tensile properties of scarf joints (SJs) created from several polymers, including ABS, PETG, and PLA, adhered with Araldite^® 2015 and Sikaforce^® 7752 adhesives. The characteristics of the adherends were assessed prior to examining the adhesive efficacy in the SJ configuration. Experimental evaluations quantified failure modes, joint strength, assembly stiffness, and energy at failure, comparing findings with predictions from a cohesive zone model (CZM). The objective was to determine the ideal combination of materials and adhesives for enhanced joint performance. Results indicated that joint performance is greatly affected by the adherend material, adhesive selection, and scarf angle. PLA and Araldite^® 2015 typically exhibited optimal strength and stiffness, but Sikaforce^® 7752 demonstrated enhanced energy absorption for extended bonding lengths. Full article

(This article belongs to the Special Issue Innovative and Sustainable Advances in Polymer Composites for Additive Manufacturing: Processing, Microstructure, Machining, and Mechanical Properties)

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15 pages, 3579 KiB

Open AccessArticle

Mechanical, Morphological, and Electrical Characteristics of Cu-Loaded Acrylic Paint on a Fused Deposition Modeling Printed Polylactic Acid Surface

by Sudhir Kumar, Pulkit Tiwari and Seyed Saeid Rahimian Koloor

Processes 2025, 13(4), 1059; https://doi.org/10.3390/pr13041059 (registering DOI) - 2 Apr 2025

Abstract

Fused deposition modeling (FDM) printing has become increasingly popular for exploring advanced material matrices with a polymeric base. This study uses a low-energy method to investigate the metallization process on a surface created by 3D printing. This involves using an acrylic-paint-based solution to [...] Read more.

Fused deposition modeling (FDM) printing has become increasingly popular for exploring advanced material matrices with a polymeric base. This study uses a low-energy method to investigate the metallization process on a surface created by 3D printing. This involves using an acrylic-paint-based solution to disperse the copper (Cu) powder on a polylactic acid (PLA) substrate, allowing for an evaluation of the fabricated samples’ mechanical, morphological, absorbance, and capacitance properties. The study findings indicate a gradual increase in tensile strength as the content of Cu in the acrylic paint layer on the PLA substrate increases. There was a clear and consistent increase in the tensile strength of the specimen, ranging from 13.5 MPa (sample 1) to 15.6 MPa (sample 5). Similarly, the percentage of strain at failure also showed a noticeable increase, ranging from 4.2% (sample 1) to 8.6% (sample 5). The scanning electron microscopy (SEM) investigation revealed the presence of completely enveloped Cu particles in acrylic paint on the FDM-printed surface of the PLA. The Ultraviolet–Visible Diffuse Reflectance Spectroscopy (UV–Vis DRS) indicated a significant change in the absorbance pattern as the copper content in the layer increased. The augmented absorbance values serve as an advantage because they demonstrate enhanced UV light interaction, which correlates with the increase in capacitance measurements of 6 to 8 pF. This result suggests that the fabricated sample potentially leads to favorable alterations in material characteristics for applications that demand stable capacitance alongside improved mechanical properties. The SEM analysis supported the observed trends. Full article

(This article belongs to the Special Issue Development and Characterization of Advanced Polymer Nanocomposites)

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19 pages, 1488 KiB

Open AccessArticle

Who Is Leading in Communication Tone? Wavelet Analysis of the Fed and the ECB

by Pinar Deniz and Thanasis Stengos

J. Risk Financial Manag. 2025, 18(4), 191; https://doi.org/10.3390/jrfm18040191 (registering DOI) - 2 Apr 2025

Abstract

This study examines the relationship between the communication tone of the Fed and that of the ECB over the period from January 2000 to September 2023. The tones were measured using both lexicon-based and transform-based algorithms. Wavelet coherence analysis helped distinguish the scale [...] Read more.

This study examines the relationship between the communication tone of the Fed and that of the ECB over the period from January 2000 to September 2023. The tones were measured using both lexicon-based and transform-based algorithms. Wavelet coherence analysis helped distinguish the scale of the relationship over time and frequency domains. Our findings suggest a dynamic process regarding the lead/lag positions, and the similarity of the two algorithms in the medium run highlights the leading role of the ECB during the (pre-)crisis period of the US and the leading role of the Fed during the QE period of the ECB. Hence, the variability in the leader/follower role suggests no strong predictive structural relationship between the two communication tones. Full article

(This article belongs to the Special Issue Machine Learning Based Risk Management in Finance and Insurance)

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20 pages, 998 KiB

Open AccessReview

Unraveling the Complexities of Myeloid-Derived Suppressor Cells in Inflammatory Bowel Disease

by Yangzhuangzhuang Zhu and Siyan Cao

Int. J. Mol. Sci. 2025, 26(7), 3291; https://doi.org/10.3390/ijms26073291 (registering DOI) - 2 Apr 2025

Abstract

Myeloid-derived suppressor cells (MDSCs) regulate immune responses in many pathological conditions, one of which is inflammatory bowel disease (IBD), an incurable chronic disorder of the digestive tract and beyond. The pathophysiology of IBD remains unclear, likely involving aberrant innate and adaptive immunity. Studies [...] Read more.

Myeloid-derived suppressor cells (MDSCs) regulate immune responses in many pathological conditions, one of which is inflammatory bowel disease (IBD), an incurable chronic disorder of the digestive tract and beyond. The pathophysiology of IBD remains unclear, likely involving aberrant innate and adaptive immunity. Studies have reported altered population of MDSCs in patients with IBD. However, their distribution varies among patients and different preclinical models of IBD. The expansion and activation of MDSCs are likely driven by various stimuli during intestinal inflammation, but the in-depth mechanisms remain poorly understood. The role of MDSCs in the pathogenesis of IBD appears to be paradoxical. In addition to intestinal inflammation, suppressive MDSCs may promote colitis-to-colon-cancer transition. In this Review, we summarize recent progresses on the features, activation, and roles of MDSCs in the development of IBD and IBD-associated colon cancer. Full article

(This article belongs to the Special Issue New Advances in Autoimmune Diseases)

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28 pages, 2270 KiB

Open AccessReview

Bacterial Cellulose for Scalable and Sustainable Bio-Gels in the Circular Economy

by Giovanni Venturelli, Federica Villa, Mariagioia Petraretti, Giuseppe Guagliano, Marinella Levi and Paola Petrini

Gels 2025, 11(4), 262; https://doi.org/10.3390/gels11040262 (registering DOI) - 2 Apr 2025

Abstract

Microbial-derived materials are emerging for applications in biomedicine, sensors, food, cosmetics, construction, and fashion. They offer considerable structural properties and process reproducibility compared to other bio-based materials. However, challenges related to efficient and sustainable large-scale production of microbial-derived materials must be addressed to [...] Read more.

Microbial-derived materials are emerging for applications in biomedicine, sensors, food, cosmetics, construction, and fashion. They offer considerable structural properties and process reproducibility compared to other bio-based materials. However, challenges related to efficient and sustainable large-scale production of microbial-derived materials must be addressed to exploit their potential fully. This review analyzes the synergistic contribution of circular, sustainable, and biotechnological approaches to enhance bacterial cellulose (BC) production and fine-tune its physico-chemical properties. BC was chosen as an ideal example due to its mechanical strength and chemical stability, making it promising for industrial applications. The review discusses upcycling strategies that utilize waste for microbial fermentation, simultaneously boosting BC production. Additionally, biotechnology techniques are identified as key to enhance BC yield and tailor its physico-chemical properties. Among the different areas where cellulose-based materials are employed, BC shows promise for mitigating the environmental impact of the garment industry. The review emphasizes that integrating circular and biotechnological approaches could significantly improve large-scale production and enhance the tunability of BC properties. Additionally, these approaches may simultaneously provide environmental benefits, depending on their future progresses. Future advancements should prioritize circular fermentation and biotechnological techniques to expand the potential of BC for sustainable industrial applications. Full article

(This article belongs to the Special Issue Gel Materials for Green Applications)

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14 pages, 3491 KiB

Open AccessArticle

Simulation and Response of Runoff to Climate and Land-Use Changes in the Yanhe River Basin, Loess Plateau: A SWAT Model-Based Analysis

by Kun Hou, Jianhua Wang and Xiaoming Zhang

Water 2025, 17(7), 1042; https://doi.org/10.3390/w17071042 (registering DOI) - 2 Apr 2025

Abstract

Ecological restoration projects in the Loess Plateau have significantly altered the underlying surface, which has profoundly affected the regional water cycle. In the context of the ongoing climate change, quantitatively identifying the factors influencing runoff changes and simulating runoff responses to various land [...] Read more.

Ecological restoration projects in the Loess Plateau have significantly altered the underlying surface, which has profoundly affected the regional water cycle. In the context of the ongoing climate change, quantitatively identifying the factors influencing runoff changes and simulating runoff responses to various land management policies are essential for achieving sustainable development in arid/semi-arid regions. Daily hydrological and meteorological data from 1981 to 2020 along with the SWAT model were employed to analyze the attribution of runoff changes in the Yanhe River basin and simulate runoff responses under different climate and land-use scenarios. The results show the following: (1) the improvement of the underlying surface conditions appeared to be the leading factor of runoff retention, with a contribution of 81.21%, while the influence of climate change on runoff was minimal; (2) woodland generally exhibited superior performance in retaining runoff compared to grassland under diverse climate conditions; (3) converting farmland on slopes between 15 and 25 degrees into woodland and farmland on slopes exceeding 25 degrees into grassland demonstrated to be a more effective approach to controlling soil erosion; (4) it is recommended that a balance between water resource utilization and the extent of afforestation should be considered concurrently in future ecological restoration. Full article

(This article belongs to the Section Water and Climate Change)

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16 pages, 1449 KiB

Open AccessArticle

The Essential Oil Composition in Commercial Samples of Verbena officinalis L. Herb from Different Origins

by Ain Raal, Getter Dolgošev, Tetiana Ilina, Alla Kovalyova, Martin Lepiku, Andriy Grytsyk and Oleh Koshovyi

Crops 2025, 5(2), 16; https://doi.org/10.3390/crops5020016 (registering DOI) - 2 Apr 2025

Abstract

The key objective of this study was to determine the yield and chemical composition of eight commercial samples and one collected sample of common vervain (Verbena officinalis L.) herb essential oil (EO) originating from seven different countries, and subsequently, to assess its [...] Read more.

The key objective of this study was to determine the yield and chemical composition of eight commercial samples and one collected sample of common vervain (Verbena officinalis L.) herb essential oil (EO) originating from seven different countries, and subsequently, to assess its potential for treating anxiety and depression. According to GC-MS analysis, 90 compounds were identified, 49 of which were discovered for the first time in V. officinalis EO. The plants with the highest oil content are from Greece (4.7 mL/kg) and South Carolina, USA (5.2 mL/kg). The chemical markers for the studied chemotypes of EO of V. officinalis are the terpenoids o-cymene, p-cymene, L-carvone, thymol, carvacrol, α-curcumin, hexahydrofarnesyl acetone, phytol, (E)-β-ionone, and phenylpropene anethole. The chemotype from the UK demonstrated the greatest affinity to the continuum under study; it has the highest levels of similarity—85.2% with the chemotype from Greece, 69.4% with the chemotype from the USA, 68.2% with the chemotype from Estonia (2), 58.7% with the chemotype from Germany, and 58.6% with the chemotype from Hungary. The chemotypes identified have the potential for use in the treatment of anxiety and depression. Full article

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20 pages, 7408 KiB

Open AccessArticle

Etching and Precursor Effects on Plasma-Modified Waste Polyethylene Terephthalate (PET) to Laccase Immobilization Applied in Catechol Biodegradation for Water Treatment

by Reyna Orsua-Gaona, Rosa Idalia Narro-Céspedes, Anna Ilina, Luis Fernando Mora-Cortés, Yadira Karina Reyes-Acosta, Gustavo Soria-Arguello, Cynthia Luevano-Martínez, Miriam Paulina Luévanos-Escareño and Claudia Gabriela Cuellar-Gaona

Coatings 2025, 15(4), 421; https://doi.org/10.3390/coatings15040421 (registering DOI) - 2 Apr 2025

Abstract

Polyethylene terephthalate (PET) is a polyester used in the beverage bottling industry that generates a serious pollution problem. Films were obtained to reuse discarded PET bottles, and their surface was modified to determine their effectiveness in supporting the immobilization of the laccase enzyme [...] Read more.

Polyethylene terephthalate (PET) is a polyester used in the beverage bottling industry that generates a serious pollution problem. Films were obtained to reuse discarded PET bottles, and their surface was modified to determine their effectiveness in supporting the immobilization of the laccase enzyme applied to a catechol biodegradation assay. Radiofrequency (RF) plasma was used to modify the PET surface using different precursors: (a) with the use of air as precursor, the effect of the etching caused by the air on the greater or lesser immobilization was observed; (b) with the use of ethylenediamine, a mixture of N₂/H_2, or aniline as precursors, it was observed which of these three precursors presented the greater or lesser number of amino groups deposited on the PET surface. After plasma modification, the films were cross-linked with glutaraldehyde to immobilize the laccase enzyme. Finally, the catechol test was performed. It was found that the best etching time using air as a precursor was 90 min, and the precursor that caused a higher insertion of amino groups on the surface was ethylenediamine, which reached a density of amino groups of 3.98 ± 0.10 g·mm⁻². The highest percentage of laccase immobilization achieved on the surface of ethylenediamine-modified PET was 97.30%. In the catechol assay, the highest retention was 86.11%. This research reveals how the effect of plasma increases the surface area on a PET surface and, in conjunction with ethylenediamine as the best precursor of the three precursors evaluated, can immobilize a greater amount of enzyme and oxidize more catechol. There is no scientific evidence from previous studies that used air plasma technology to erode and then used three different precursors to modify a surface to immobilize the laccase enzyme and remove a water contaminant. Full article

(This article belongs to the Special Issue Advanced Technology in Environmental Remediation and Resource Utilization, 2nd Edition)

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22 pages, 1017 KiB

Open AccessArticle

Evaluating the Positive Functioning at Work (PF-W) Questionnaire: Insights into Predictive Factors of Well-Being Among Spanish Workers

by Adrián García-Selva, Marie-Carmen Neipp and Beatriz Martín-del-Río

Behav. Sci. 2025, 15(4), 455; https://doi.org/10.3390/bs15040455 (registering DOI) - 2 Apr 2025

Abstract

This study examines the interplay between individual predictors (self-efficacy) and organizational factors (perceived organizational support) within the framework of the PERMA+4 model to promote workplace well-being. Data were collected from 545 employees (57.8% women) using self-reported questionnaires and analyzed through structural equation modeling. [...] Read more.

This study examines the interplay between individual predictors (self-efficacy) and organizational factors (perceived organizational support) within the framework of the PERMA+4 model to promote workplace well-being. Data were collected from 545 employees (57.8% women) using self-reported questionnaires and analyzed through structural equation modeling. The results indicate that self-efficacy positively influences seven dimensions of the PERMA+4 model, while perceived organizational support significantly affects five dimensions. Positive emotions are identified as a mediator, amplifying the impact of PERMA+4 dimensions on job satisfaction and organizational commitment. Specifically, positive emotions have a positive effect on job satisfaction, underscoring their pivotal role in the workplace well-being. These findings validate the PERMA+4 model as a comprehensive framework for understanding workplace well-being, emphasizing the dynamic interaction between individual and organizational factors. Moreover, they provide actionable insights for interventions aimed at enhancing employee satisfaction and long-term commitment by fostering self-efficacy, organizational support, and positive emotions. Full article

(This article belongs to the Special Issue Promoting Flourishing at Work: Innovations in Positive Work and Organizational Psychology)

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17 pages, 3150 KiB

Open AccessArticle

Enhanced Immunity and Infection Resistance in Mice Through Co-Expression of Porcine IL-3, IL-7, and IL-15 Fusion Molecules in Yarrowia lipolytica

by Junjie Peng, Linhan Zhang, Jiangling Li, Xuebin Lv, Rui Liu, Jianlin Chen, Gang Wang and Rong Gao

Biology 2025, 14(4), 366; https://doi.org/10.3390/biology14040366 (registering DOI) - 2 Apr 2025

Abstract

China’s livestock industry grapples with challenges posed by infectious diseases and the misuse of antibiotics, resulting in a heightened risk of drug-resistant pathogens. This study explored the immunomodulatory effects of co-expressing porcine interleukin 3, 7, and 15 in Yarrowia lipolytica, denoted as [...] Read more.

China’s livestock industry grapples with challenges posed by infectious diseases and the misuse of antibiotics, resulting in a heightened risk of drug-resistant pathogens. This study explored the immunomodulatory effects of co-expressing porcine interleukin 3, 7, and 15 in Yarrowia lipolytica, denoted as Po1h-IL-3/7/15. A 42-day experiment involving mouse immunization and pathogen challenge was conducted, during which in vivo assessments of antibodies, immune-related cells, and gene expression were detected following oral administration of Po1h-IL-3/7/15. Immunological alterations in mice were analyzed using flow cytometry, qRT-PCR, ELISA, and HE staining. Notably, the serum IgG and intestinal sIgA levels in the Po1h-IL-3/7/15 group were substantially elevated compared to the control groups (p < 0.01), so were the contents of IL-7, IL-15, IFN-γ, IL-22, IL-23, and TNF-α. Furthermore, there was a marked increase in naïve T cells and central memory T cells, accompanied by a significant decrease in regulatory T cells in peripheral blood. Post-challenge with Staphylococcus aureus or Salmonella typhimurium, the expression levels of BD2, IL-1β, IL-8, Jak1, RegⅢ, S100A8, STAT1, and TNF-α genes in the intestines of the Po1h-IL-3/7/15 group were markedly higher than those in the control groups (p < 0.01). Following the challenges, the survival rate of the Po1h-IL-3/7/15 group was 100%, a significant increase compared to the 20% and 40% survival rates observed in the control groups (p < 0.05). These results confirm that IL-3/7/15 significantly boosts innate immunity, humoral and cell-mediated immune responses, and intestinal mucosal immunity in mice, enhancing resistance to bacterial infections and exhibiting potent protective effects. Full article

(This article belongs to the Special Issue Immune Response Regulation in Animals)

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8 pages, 1295 KiB

Open AccessArticle

Bubble Structure in Isotopes of Lu to Hg

by Changhoon Song, Yongbeom Choi, Youngman Kim and Chang-Hwan Lee

Particles 2025, 8(2), 37; https://doi.org/10.3390/particles8020037 (registering DOI) - 2 Apr 2025

Abstract

Bubble nuclei, characterized by a depletion in nucleon density at the nuclear center, are investigated within the atomic number range

71 \leq Z \leq 80

using the Deformed Relativistic Hartree–Bogoliubov theory in continuum. This study extends previous investigations, which were limited to even–even [...] Read more.

Bubble nuclei, characterized by a depletion in nucleon density at the nuclear center, are investigated within the atomic number range

71 \leq Z \leq 80

using the Deformed Relativistic Hartree–Bogoliubov theory in continuum. This study extends previous investigations, which were limited to even–even isotopes, by incorporating even–odd, odd–even, and odd–odd nuclei within this range. The extension is achieved by introducing the blocking effect into the point-coupling approach to ensure self-consistency. Following previous studies, we define a nucleus as a bubble candidate if the bubble parameter exceeds

B_{p}^{★} = 20 %

, and identify five bubble nuclei in both even-Z and odd-Z nuclei groups, based on the highest

B_{p}^{★}

values. The formation of bubble structures is confirmed through an analysis of proton single-particle energy levels of the most centrally depleted nuclei across four categories: even–odd, even–even, odd–even, and odd–odd. Full article

(This article belongs to the Special Issue Selected Papers from the “7th Workshop on the Nuclear Mass Table with DRHBc Theory”)

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10 pages, 678 KiB

Open AccessArticle

Indwelling Catheters Should Be Restricted in Primary and Revision Arthroplasty: A Retrospective Analysis After Changes to Hospital Standard Perioperative Treatment Protocol

by Matthias Schnetz, Tim Jakobi, Larissa Ewald, Alexander Klug, Matthias Münzberg and Yves Gramlich

Antibiotics 2025, 14(4), 368; https://doi.org/10.3390/antibiotics14040368 (registering DOI) - 2 Apr 2025

Abstract

Background: Indwelling catheters are used in the perioperative management of patients treated with total joint arthroplasty (TJA) to facilitate fluid control, ease postoperative miction until patients are able to ambulate, and prevent postoperative urinary retention (POUR). However, in TJA, they may be associated [...] Read more.

Background: Indwelling catheters are used in the perioperative management of patients treated with total joint arthroplasty (TJA) to facilitate fluid control, ease postoperative miction until patients are able to ambulate, and prevent postoperative urinary retention (POUR). However, in TJA, they may be associated with a higher risk of urinary tract infections (UTIs). The aim of the study was to analyze the rates of urinary tract infections and POUR. Methods: Between 2021 and 2022, this study retrospectively identified patients before and after a change in the hospital standard perioperative treatment protocol towards a more restrictive use of indwelling catheters for TJA. In 2021, the use of indwelling catheters involved standard care, but the use was restricted in 2022. Results: A total of 1521 patients were included: 636 patients (41.8%) underwent primary arthroplasty, 646 (42.5%) underwent revision arthroplasty, and 239 (15.7%) underwent hip arthroplasty for femoral neck fractures. Standard use of indwelling catheters significantly decreased from 62.0% to 38.0% (p < 0.001), and the rate of UTI was significantly lower after the protocol change (4.7% vs. 1.2%; p < 0.001). Perioperative urine catheterization was a significant risk factor for UTI (OR = 4.22; p < 0.001), and UTI was a significant risk factor for PJI (OR = 9.99; p < 0.001). POUR increased slightly from 0.9% to 1.8%, but the difference was not significant. POUR was mostly diagnosed following the exchange of the acetabular component in revision arthroplasty (n = 11; 52.4%). Conclusions: Indwelling catheter use was associated with high rates of UTIs. Restricting perioperative use of indwelling catheters was effective in preventing UTIs while causing only a moderate increase in easily treatable postoperative urinary retention. Therefore, the use of indwelling catheters should be avoided in arthroplasty whenever possible. Full article

(This article belongs to the Special Issue Prevention, Diagnostic and Antibiotic Treatment of Periprosthetic Joint and Fracture Related Infection, 2nd Edition)

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25 pages, 2512 KiB

Open AccessReview

How Does HDL Participate in Atherogenesis? Antioxidant Activity Versus Role in Reverse Cholesterol Transport

by Paul N. Durrington, Bilal Bashir and Handrean Soran

Antioxidants 2025, 14(4), 430; https://doi.org/10.3390/antiox14040430 (registering DOI) - 2 Apr 2025

Abstract

Low-density lipoprotein (LDL) chemically modified by reactive oxygen species (ROS), for example, leaking from red blood cells in the vascular compartment, more readily crosses the vascular endothelium than does nonoxidatively modified LDL to enter tissue fluid. Oxidatively modified LDL (oxLDL) may also be [...] Read more.

Low-density lipoprotein (LDL) chemically modified by reactive oxygen species (ROS), for example, leaking from red blood cells in the vascular compartment, more readily crosses the vascular endothelium than does nonoxidatively modified LDL to enter tissue fluid. Oxidatively modified LDL (oxLDL) may also be created in the tissue fluid by ROS leaking from cells by design, for example, by inflammatory white cells, or simply leaking from other cells as a consequence of oxygen metabolism. As well as oxLDL, glycatively modified LDL (glycLDL) is formed in the circulation. High-density lipoprotein (HDL) appears capable of decreasing the burden of lipid peroxides formed on LDL exposed to ROS or to glucose and its metabolites. The mechanism for this that has received the most attention is the antioxidant activity of HDL, which is due in large part to the presence of paraoxonase 1 (PON1). PON1 is intimately associated with its apolipoprotein A1 component and with HDL’s lipid domains into which lipid peroxides from LDL or cell membranes can be transferred. It is frequently overlooked that for PON1 to hydrolyze lipid substrates, it is essential that it remain by virtue of its hydrophobic amino acid sequences within a lipid micellar environment, for example, during its isolation from serum or genetically modified cells in tissue culture. Otherwise, it may retain its capacity to hydrolyze water-soluble substrates, such as phenyl acetate, whilst failing to hydrolyze more lipid-soluble molecules. OxLDL and probably glycLDL, once they have crossed the arterial endothelium by receptor-mediated transcytosis, are rapidly taken up by monocytes in a process that also involves scavenger receptors, leading to subendothelial foam cell formation. These are the precursors of atheroma, inducing more monocytes to cross the endothelium into the lesion and the proliferation and migration of myocytes present in the arterial wall into the developing lesion, where they transform into foam cells and fibroblasts. The atheroma progresses to have a central extracellular lake of cholesteryl ester following necrosis and apoptosis of foam cells with an overlying fibrous cap whilst continuing to grow concentrically around the arterial wall by a process involving oxLDL and glycLDL. Within the arterial wall, additional oxLDL is generated by ROS secreted by inflammatory cells and leakage from cells generally when couplet oxygen is reduced. PON1 is important for the mechanism by which HDL opposes atherogenesis, which may provide a better avenue of inquiry in the identification of vulnerable individuals and the provision of new therapies than have emerged from the emphasis placed on its role in RCT. Full article

(This article belongs to the Special Issue Antioxidant Role of High-Density Lipoprotein)

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