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12 pages, 418 KiB  
Article
Sarcopenia as a Prognostic Factor for Critical Limb Ischemia: A Prospective Cohort Study
by Paula Luque-Linero, Emilio-Javier Frutos-Reoyo, Luis Castilla-Guerra, Miguel-Ángel Rico-Corral, Prado Salamanca-Bautista and Fernando Garrachón-Vallo
J. Clin. Med. 2025, 14(15), 5388; https://doi.org/10.3390/jcm14155388 - 31 Jul 2025
Viewed by 260
Abstract
Introduction and Aim: Sarcopenia has emerged as a key prognostic factor in patients with chronic limb-threatening ischemia (CLTI), with potential implications for clinical decision-making. This study aimed to assess the association between sarcopenia and clinical outcomes, mortality, and amputation, using simple, accessible screening [...] Read more.
Introduction and Aim: Sarcopenia has emerged as a key prognostic factor in patients with chronic limb-threatening ischemia (CLTI), with potential implications for clinical decision-making. This study aimed to assess the association between sarcopenia and clinical outcomes, mortality, and amputation, using simple, accessible screening tools in a CLTI population. Methods: In this prospective, single-center study conducted between December 2023 and December 2024, 170 patients with CTLI were enrolled. Sarcopenia screening was performed using the SARC-F (strength, assistance in walking, rising from a chair, climbing stairs, falls) questionnaires, handgrip strength measurement, and calf circumference, adjusted for body mass index and sex. The primary outcome was 6-month all-cause mortality and/or major amputation. Results: Sarcopenia was identified in 77 patients (45.3%). Compared to non-sarcopenic individuals, sarcopenic patients were significantly older. They exhibited greater functional impairment, as well as poorer nutritional and muscle status. They also had significantly higher in-hospital mortality (16.9% vs. 3.2%, p = 0.002), 30-day mortality (24.7% vs. 4.3%, p = 0.001), and 6-month mortality (50.6% vs. 15.1%, p = 0.001). Sarcopenia was significantly associated with the primary outcome in univariate analysis (HR: 2.05; 95% CI: 1.31–3.20; p = 0.002) and remained an independent predictor after multivariate adjustment (HR: 1.95; 95% CI: 1.01–3.79; p = 0.048). Conclusions: Sarcopenia is a strong, independent predictor of poor outcome in patients with CLTI. Its detection through simple tools offers an easy and cost-effective strategy to improve risk stratification and guide early intervention through exercise-based therapy. Full article
(This article belongs to the Section Clinical Rehabilitation)
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14 pages, 637 KiB  
Article
The Association Between Bell’s Palsy and Vestibular Dysfunction in Relation to IgG Antibodies to Neurotropic Viruses
by Krsto Dawidowsky, Srecko Branica, Lana Kovac Bilic, Zrinka Bosnjak, Marija Pastorcic-Grgic, Gorazd Poje and Barbara Dawidowsky
J. Clin. Med. 2025, 14(15), 5290; https://doi.org/10.3390/jcm14155290 - 26 Jul 2025
Viewed by 362
Abstract
Background/Objectives: The aetiology of Bell’s palsy remains unclear and is typically diagnosed by exclusion. This study investigated the potential role of neurotropic viruses and explored the relationship between facial nerve impairment and vestibular dysfunction to improve the understanding of the condition. Methods: Antibodies [...] Read more.
Background/Objectives: The aetiology of Bell’s palsy remains unclear and is typically diagnosed by exclusion. This study investigated the potential role of neurotropic viruses and explored the relationship between facial nerve impairment and vestibular dysfunction to improve the understanding of the condition. Methods: Antibodies against herpes simplex virus (HSV) and varicella-zoster virus (VZV) were assessed using ELISA. Vestibular function was evaluated through computerised videonystagmography, rotatory chair, and clinical vestibulospinal assessments. Facial nerve lesion localisation was determined by stapedial reflex testing. Fisher’s exact test was used for statistical analysis. Results: Of 51 patients with Bell’s palsy, 62.7% exhibited vestibular dysfunction, and 70.6% were IgG-positive for at least one neurotropic virus. Vestibular impairment was significantly more common in seropositive patients. Statistically significant associations were observed between vestibular dysfunction and viral IgG seropositivity (p < 0.0001), the severity of vestibular dysfunction and facial paresis (p = 0.0126), and the side of vestibular impairment and the side of facial palsy (p < 0.0001), with 90.6% of cases showing ipsilateral involvement. Conclusions: These findings support the hypothesis that neurotropic viruses may act as a common pathological factor in both Bell’s palsy and associated vestibular dysfunction. Full article
(This article belongs to the Section Otolaryngology)
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16 pages, 715 KiB  
Article
Postural Variability in Sitting: Comparing Comfortable, Habitual, and Correct Strategies Across Chairs
by Yi-Lang Chen and Li-Peng Zhang
Appl. Sci. 2025, 15(13), 7239; https://doi.org/10.3390/app15137239 - 27 Jun 2025
Viewed by 571
Abstract
Background/Objectives: Prolonged sitting is linked to musculoskeletal discomfort, yet optimal sitting posture remains poorly defined, and the consistency with which individuals reproduce specific sitting strategies is unclear. This study examined postural variability across three sitting strategies—comfortable, habitual, and correct—using three common chair types: [...] Read more.
Background/Objectives: Prolonged sitting is linked to musculoskeletal discomfort, yet optimal sitting posture remains poorly defined, and the consistency with which individuals reproduce specific sitting strategies is unclear. This study examined postural variability across three sitting strategies—comfortable, habitual, and correct—using three common chair types: a stool, computer chair, and ergonomic chair. Methods: Thirty healthy young adults (fifteen men, fifteen women) participated. Global sagittal joint angles—head inclination (HI), trunk angle (TA), and knee angle (KA)—were measured using a motion analysis system across five repetitions per condition. Results: The chair type significantly influenced HI and TA (p < 0.001), with ergonomic chairs encouraging more upright trunk postures. The sitting strategy significantly affected TA and KA (p < 0.01), with comfortable sitting associated with more extended angles. Women exhibited greater TA (114.8° vs. 109.0°, p < 0.001) and lower within-subject variability. Substantial postural variability was observed across all conditions, with mean ranges exceeding minimum detectable change thresholds for HI (10.3°), TA (6.9°), and KA (11.3°). Notably, correct sitting reduced KA variability compared to other strategies (p < 0.01). Conclusions: These findings highlight the individualized and variable nature of sitting posture, even under controlled instructions. The results question the reliability of memory-based seat adjustments and emphasize the need for dynamic, user-centered ergonomic design and personalized clinical guidance to support musculoskeletal health. Full article
(This article belongs to the Special Issue Seating Comfort and Biomechanical Application)
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31 pages, 1988 KiB  
Article
The Effect of Macroeconomic Announcements on U.S. Treasury Markets: An Autometric General-to-Specific Analysis of the Greenspan Era
by James J. Forest
Econometrics 2025, 13(3), 24; https://doi.org/10.3390/econometrics13030024 - 21 Jun 2025
Viewed by 1112
Abstract
This research studies the impact of macroeconomic announcement surprises on daily U.S. Treasury excess returns during the heart of Alan Greenspan’s tenure as Federal Reserve Chair, addressing the possible limitations of standard static regression (SSR) models, which may suffer from omitted variable bias, [...] Read more.
This research studies the impact of macroeconomic announcement surprises on daily U.S. Treasury excess returns during the heart of Alan Greenspan’s tenure as Federal Reserve Chair, addressing the possible limitations of standard static regression (SSR) models, which may suffer from omitted variable bias, parameter instability, and poor mis-specification diagnostics. To complement the SSR framework, an automated general-to-specific (Gets) modeling approach, enhanced with modern indicator saturation methods for robustness, is applied to improve empirical model discovery and mitigate potential biases. By progressively reducing an initially broad set of candidate variables, the Gets methodology steers the model toward congruence, dispenses unstable parameters, and seeks to limit information loss while seeking model congruence and precision. The findings, herein, suggest that U.S. Treasury market responses to macroeconomic news shocks exhibited stability for a core set of announcements that reliably influenced excess returns. In contrast to computationally costless standard static models, the automated Gets-based approach enhances parameter precision and provides a more adaptive structure for identifying relevant predictors. These results demonstrate the potential value of incorporating interpretable automated model selection techniques alongside traditional SSR and Markov switching approaches to improve empirical insights into macroeconomic announcement effects on financial markets. Full article
(This article belongs to the Special Issue Advancements in Macroeconometric Modeling and Time Series Analysis)
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11 pages, 479 KiB  
Article
Functional Status Enhances the FRAX® Prediction of Fractures in Myasthenia Gravis: A 10-Year Cohort Study
by Shingo Konno, Takafumi Uchi, Hideo Kihara and Hideki Sugimoto
J. Clin. Med. 2025, 14(9), 3260; https://doi.org/10.3390/jcm14093260 - 7 May 2025
Viewed by 514
Abstract
Background: Patients with myasthenia gravis (MG) are susceptible to fractures due to glucocorticoid (GC) use and disease-related functional impairment affecting activities of daily living (ADL). The Fracture Risk Assessment Tool (FRAX®) estimates fracture probability but does not incorporate disease-specific functional [...] Read more.
Background: Patients with myasthenia gravis (MG) are susceptible to fractures due to glucocorticoid (GC) use and disease-related functional impairment affecting activities of daily living (ADL). The Fracture Risk Assessment Tool (FRAX®) estimates fracture probability but does not incorporate disease-specific functional status. We investigated whether combining FRAX® with the Myasthenia Gravis Activities of Daily Living (MG-ADL) scale improves fracture risk stratification in MG patients. Methods: This single-center prospective cohort study followed 53 MG patients for 10 years (2012–2022) at Toho University Ohashi Medical Center, Japan. Patients were categorized into four groups based on baseline FRAX® probability (calculated with bone mineral density [BMD]) and MG-ADL scores using median splits: high FRAX®/high MG-ADL (HH), high FRAX®/low MG-ADL (HL), low FRAX®/high MG-ADL (LH), and low FRAX®/low MG-ADL (LL). The primary outcome was incident major osteoporotic fracture (MOF). Results: Over 10 years, nine MOFs occurred: seven in the HH group (43.8%), two in the HL group (16.7%), and none in the LH or LL groups. Fracture-free survival differed significantly among the groups (log-rank p < 0.001), with the HH group exhibiting the lowest survival rate. Baseline characteristics, including age, disease duration, MG severity scores, BMD, and FRAX® scores, differed significantly among groups. Specific MG-ADL items reflecting greater impairment (impairment of ability to arise from a chair, double vision, and ptosis) were significantly more pronounced in the HH group at baseline. Conclusions: Combining baseline FRAX® scores with the MG-ADL assessment effectively stratifies long-term MOF risk in patients with MG. Individuals with both high FRAX® and high MG-ADL represent a particularly high-risk subgroup. This dual-assessment approach may improve the identification of patients requiring targeted preventive interventions. Full article
(This article belongs to the Special Issue New Advances in Myasthenia Gravis)
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13 pages, 1078 KiB  
Article
Understanding Cybersickness and Presence in Seated VR: A Foundation for Exploring Therapeutic Applications of Immersive Virtual Environments
by Witold Pawełczyk, Dorota Olejarz, Zofia Gaweł, Magdalena Merta, Aleksandra Nowakowska, Magdalena Nowak, Anna Rutkowska, Ladislav Batalik and Sebastian Rutkowski
J. Clin. Med. 2025, 14(8), 2718; https://doi.org/10.3390/jcm14082718 - 15 Apr 2025
Cited by 1 | Viewed by 1202
Abstract
Background/Objectives: To assess the spatial presence and impact of an immersive virtual reality (VR) walk on symptoms of cybersickness, emotions, and participant engagement, with the aim of providing insights applicable to future therapeutic VR interventions for individuals with limited mobility. Methods: The experiment [...] Read more.
Background/Objectives: To assess the spatial presence and impact of an immersive virtual reality (VR) walk on symptoms of cybersickness, emotions, and participant engagement, with the aim of providing insights applicable to future therapeutic VR interventions for individuals with limited mobility. Methods: The experiment involved 30 healthy individuals who used VR headsets while seated on chairs to experience a 360° virtual tour of the Venice Canals in Los Angeles. The effect of immersion was evaluated using the Virtual Reality Sickness Questionnaire (VRSQ) to measure cybersickness symptoms, the International Positive and Negative Affect Schedule-Short Form (I-PANAS-SF) to assess emotions, the Spatial Presence Experience Scale (SPES) to evaluate spatial presence, and the Flow State Scale (FSS) to quantify the flow state. Results: The results indicated that the virtual walk elicited both positive and negative reactions. The increase in eye strain (+0.66), general discomfort (+0.6), and headache (+0.43) was achieved in the VRSQ scale. Despite experiencing nausea and oculomotor symptoms, participants reported a high level of flow (range of scale items from 3.47 to 3.70), suggesting a beneficial impact of immersion on their well-being. Furthermore, the analysis of the I-PANAS-SF results revealed a predominance of positive emotions, indicating a favorable perception of the experience. However, the SPES scores exhibited variability in the perception of spatial presence (mean spatial presence score 3.74, SD 2.06), likely influenced by the characteristics of the visual material used. Conclusions: Overall, the immersive VR walk, despite the potential risk of cybersickness symptoms, as a seated passive exploration still promoted feelings of satisfaction and fulfillment, allowing the participants to actively engage with the virtual environment. These findings suggest that seated VR experiences hold promise as a tool for promoting well-being, but further research is needed to address cybersickness and optimize VR content for therapeutic use in populations with limited mobility. Full article
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19 pages, 4983 KiB  
Article
The Role of Chair Design in Dental Ergonomics: A Kinematic Assessment of Movement and Ergonomic Risk
by Fabian Holzgreve, Jasmin Preuß, Christina Erbe, Werner Betz, Eileen M. Wanke, Gerhard Oremek, Doerthe Brueggmann, Albert Nienhaus, David A. Groneberg, Christian Maurer-Grubinger and Daniela Ohlendorf
Bioengineering 2025, 12(4), 353; https://doi.org/10.3390/bioengineering12040353 - 29 Mar 2025
Viewed by 948
Abstract
Introduction: Dental professionals are susceptible to musculoskeletal disorders due to unphysiological postures during treatment, which can be mitigated by the choice of a work chair to improve ergonomic working posture. Methods: In this study, the influence of five different work chairs on the [...] Read more.
Introduction: Dental professionals are susceptible to musculoskeletal disorders due to unphysiological postures during treatment, which can be mitigated by the choice of a work chair to improve ergonomic working posture. Methods: In this study, the influence of five different work chairs on the ergonomic risk assessment using RULA and the working behaviour of 22 right-handed dentists was investigated. To this end, dental treatment was simulated on a phantom head, with the body posture recorded using an inertial motion capture system. The resulting kinematic data were converted into a continuous RULA scheme, and statistical methods (Friedman test with Conover–Iman comparisons and statistical parametric mapping) were used to compare the chairs. The significance level was set at p ≤ 0.05. Results: The RULA analysis revealed no significant differences between the task chairs that were tested; however, it should be noted that all of the task chairs exhibited an increased ergonomic risk (RULA ≥ 5), which indicates an increased risk of musculoskeletal disorders. Significant multiple comparisons (SPM analysis) between the selected chairs of the relative occurrence of total joint angles were between Chair 1 vs. 5 (p ≤ 0.03 for shoulder left flexion–extension), Chair 2 vs. 4 (p ≤ 0.03 for shoulder right flexion–extension), Chair 1 vs. 3 (p ≤ 0.03 for trunk right flexion–extension, 0.04 for trunk lateral flexion and 0.05 for elbow left flexion–extension), Chair 3 vs. 4 (p ≤ 0.05 for shoulder left flexion–extension and 0.01 shoulder right flexion–extension), and between Chair 2 vs. 3 (p ≤ 0.05 for elbow left flexion–extension). Discussion: The study’s findings indicate that the selection of work chairs did not have a significant impact on the ergonomic risk, which remained consistently high across all the chairs. Nevertheless, the analysis of joint angles demonstrated that the Ghopec chair was more frequently associated with greater joint angles, with only a few significant deviations. However, it should be noted that these significant differences in joint angles occurred only sporadically, did not demonstrate a clear and consistent trend across all the chairs, and have no clinical impact. Overall, the results confirm that the working posture of the dentists has a potential risk of developing musculoskeletal disorders, while the ergonomic design of the work chairs plays a rather subordinate role. Full article
(This article belongs to the Section Biomechanics and Sports Medicine)
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28 pages, 8368 KiB  
Article
Floor-Usage Behavior and Thermal Comfort Among Apartment Residents Under Cultural Transition in Indonesia
by Collinthia Erwindi, Kyohei Kondo, Hiroki Aoshima, Takashi Asawa and Tetsu Kubota
Sustainability 2025, 17(6), 2775; https://doi.org/10.3390/su17062775 - 20 Mar 2025
Viewed by 678
Abstract
The rapid urbanization in Southeast Asia has resulted in an increase in vertical apartment buildings, bringing notable changes in residents’ lifestyles accompanied by Westernized cultures. Focusing on Indonesia, this study delves into how residents adapt their behaviors, especially traditional floor-sitting behavior, to living [...] Read more.
The rapid urbanization in Southeast Asia has resulted in an increase in vertical apartment buildings, bringing notable changes in residents’ lifestyles accompanied by Westernized cultures. Focusing on Indonesia, this study delves into how residents adapt their behaviors, especially traditional floor-sitting behavior, to living in the different types of apartments. The study also explores energy consumption and thermal comfort in relation to floor-usage behaviors. We conducted a comprehensive questionnaire survey of more than 3300 respondents in Indonesia, with 1841 Jabodetabek samples used for analysis. The findings indicate that approximately 80% of lower-income apartment residents (Rusunawa) predominantly engaged in floor-sitting behavior and relied on fans for cooling. In contrast, approximately 75% of higher-income apartment residents (condominiums) preferred chair-sitting and used air conditioning (AC). Cluster analysis of three key factors—primary posture, foot covering, and floor covering—revealed four distinct groups. The clusters with a lower preference for floor-sitting exhibited approximately 50% higher annual electricity consumption due to AC usage, whereas the clusters favoring floor-sitting consumed less electricity, relying more on fans. However, despite variations in energy use, over 85% of respondents across all clusters were mostly reported as comfortable, indicating that behavioral adaptations with floor-sitting remain viable in achieving thermal comfort. While an increase in income level changes behaviors and energy use, the results suggest that floor-sitting is a traditional practice that serves as an effective low-energy strategy in hot and humid climates. Full article
(This article belongs to the Section Sustainable Urban and Rural Development)
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11 pages, 1353 KiB  
Article
Sex Differences in the Association Between Masticatory Function and Sarcopenia Components: The Shizuoka Study
by Sayaka Nagao-Sato, Osamu Kushida, Yasunari Kurita, Etsuko Ozaki, Nagato Kuriyama, Michitaka Kato, Rie Akamatsu, Toshinao Goda and Yasuharu Tabara
Nutrients 2025, 17(6), 968; https://doi.org/10.3390/nu17060968 - 10 Mar 2025
Viewed by 913
Abstract
Background/Objectives: Low masticatory function has been proposed as a risk factor for sarcopenia. This study investigated its potential association with body composition and physical performance in community-dwelling older adults. Methods: Participants included adults aged ≥65 years (643 men; 797 women) who [...] Read more.
Background/Objectives: Low masticatory function has been proposed as a risk factor for sarcopenia. This study investigated its potential association with body composition and physical performance in community-dwelling older adults. Methods: Participants included adults aged ≥65 years (643 men; 797 women) who volunteered for a longitudinal cohort study. Masticatory function was objectively assessed using gummy jelly and subjectively evaluated via a structured questionnaire. The skeletal muscle mass, body mass index, waist circumference, handgrip strength, gait speed, and five-time chair-stand test were assessed. Results: Objectively measured masticatory function was classified as low (12.6%), moderate (38.0%), or high (49.4%). In men, masticatory function was significantly associated with skeletal muscle mass index (low, moderate, and high: 7.4, 7.7, and 7.7 kg/m2; p = 0.005), handgrip strength (31.8, 34.2, and 35.5 kg; p < 0.001), and gait speed (1.3, 1.4, and 1.4 m/s; p = 0.003). In women, low masticatory function was linked to a higher body mass index (22.9, 22.0, and 21.9 kg/m2; p = 0.028) and waist circumference (82.9, 80.8, and 80.4 cm; p = 0.041). Moreover, these significant associations persisted after adjusting for covariates. Discrepancies were observed between objective and subjective measures of masticatory function, with approximately 40% of participants showing low objective masticatory function, perceiving their chewing ability as normal. Subjective masticatory function exhibited no significant associations with anthropometric measures or sarcopenia components. Conclusions: In men, objectively measured low masticatory function was associated with reduced skeletal muscle mass and poor physical performance; in women, it was linked to higher body mass index. Full article
(This article belongs to the Section Geriatric Nutrition)
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10 pages, 464 KiB  
Article
Assessment of Factors Related to Sarcopenia in Patients with Systemic Sclerosis
by Tuba Yuce Inel, Gozde Dervis Hakim and Merih Birlik
J. Clin. Med. 2025, 14(5), 1573; https://doi.org/10.3390/jcm14051573 - 26 Feb 2025
Viewed by 534
Abstract
Objectives: Systemic sclerosis (SSc) patients exhibit a heightened vulnerability to sarcopenia, a condition characterized by the loss of muscle mass and strength. This study aims to determine the prevalence of sarcopenia in patients with SSc and to investigate the associated factors contributing [...] Read more.
Objectives: Systemic sclerosis (SSc) patients exhibit a heightened vulnerability to sarcopenia, a condition characterized by the loss of muscle mass and strength. This study aims to determine the prevalence of sarcopenia in patients with SSc and to investigate the associated factors contributing to this condition. Methods: Eighty patients with SSc were included in the study, and their demographic and clinical characteristics, body composition by bioelectrical impedance analysis, SARC-F score, chair-stand test performance, and 4 m walking speed were recorded. Results: Among the 80 participants, 91.3% were female, with a median age of 56.5 years (range 45–65). The majority (70%) had limited SSc, and 71.3% reported at least one comorbidity. According to the International Physical Activity Questionnaire, only 12.5% of participants met the criteria for an active lifestyle. The SARC-F questionnaire indicated that 20% of patients were at risk for sarcopenia. The prevalence of sarcopenia among patients showed considerable variability: 5% (95% CI 0.1–9) were identified through the appendicular skeletal muscle index (ASMI), 8.8% (95% CI 2.4–15) via the fat-free mass index (FFMI), and a concerning 20% (95% CI 11–29) according to the skeletal muscle mass index (SSMI). A multivariate logistic regression analysis identified age as the only factor significantly influencing the SARC-F score, with an odds ratio of 1.081 (95% CI 1.012–1.154, p = 0.020). Additionally, the older age group demonstrated a lower level of physical activity, poorer chair-stand test outcome, and slower 4 m gait speeds (p = 0.013, p = 0.008, p = 0.001, respectively), as well as a higher reported frequency of falls (p = 0.039). Conclusions: Sarcopenia is a prevalent issue among individuals with SSc, particularly in the older population. This study did not identify a direct correlation between sarcopenia and SSc subtype, disease activity, or other clinical parameters. However, the need for an improved cut-off value for diagnosing sarcopenia in this specific cohort is evident. Full article
(This article belongs to the Section Geriatric Medicine)
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11 pages, 4353 KiB  
Review
G-Quadruplex Structures Formed by Human Telomere and C9orf72 GGGGCC Repeats
by Bing Yan, Monica Ching Suen, Naining Xu, Chao Lu, Changdong Liu and Guang Zhu
Int. J. Mol. Sci. 2025, 26(4), 1591; https://doi.org/10.3390/ijms26041591 - 13 Feb 2025
Viewed by 1750
Abstract
G-quadruplexes (G4s) are unique nucleic acid structures composed of guanine-rich (G-rich) sequences that can form diverse topologies based on the arrangement of their four strands. G4s have attracted attention for their potential roles in various biological processes and human diseases. In this review, [...] Read more.
G-quadruplexes (G4s) are unique nucleic acid structures composed of guanine-rich (G-rich) sequences that can form diverse topologies based on the arrangement of their four strands. G4s have attracted attention for their potential roles in various biological processes and human diseases. In this review, we focus on the G4 structures formed by human telomeric sequences, (GGGTTA)n, and the hexanucleotide repeat expansion, (GGGGCC)n, in the first intron region of the chromosome 9 open reading frame 72 (C9orf72) gene, highlighting their structural diversity and biological significance. Human telomeric G4s play crucial roles in telomere retention and gene regulation. In particular, we provide an in-depth summary of known telomeric G4s and focus on our recently discovered chair-type conformation, which exhibits distinct folding patterns. The chair-type G4s represent a novel folding pattern with unique characteristics, expanding our knowledge of telomeric G4 structural diversity and potential biological functions. Specifically, we emphasize the G4s formed by the (GGGGCC)n sequence of the C9orf72 gene, which represents the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). The thorough structural analysis in this review advances our comprehension of the disease mechanism and provides valuable insights into developing targeted therapeutic strategies in ALS/FTD. Full article
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18 pages, 7630 KiB  
Article
Evaluation of 3D-Printed Connectors in Chair Construction: A Comparative Study with Traditional Mortise-and-Tenon Joints
by Antoniu Nicolau, Marius Nicolae Baba, Camelia Cerbu, Cătălin Cioacă, Luminița-Maria Brenci and Camelia Cosereanu
Materials 2025, 18(1), 201; https://doi.org/10.3390/ma18010201 - 5 Jan 2025
Viewed by 1632
Abstract
The present paper investigates the possibility of replacing the traditional L-type corner joint used in chair construction with a 3D printed connector, manufactured using the Fused Filament Fabrication (FFF) method and black PLA as filament. The connector was designed to assemble the legs [...] Read more.
The present paper investigates the possibility of replacing the traditional L-type corner joint used in chair construction with a 3D printed connector, manufactured using the Fused Filament Fabrication (FFF) method and black PLA as filament. The connector was designed to assemble the legs with seat rails and stretchers, and it was tested under diagonal tensile and compression loads. Its performance was compared to that of the traditional mortise-and-tenon joint. Stresses and displacements of the jointed members with connector were analyzed using non-linear Finite Element Method (FEM) analysis. Both connector and mortise-and-tenon joint were employed to build chair prototypes made from beech wood (Fagus sylvatica L.). Digital Image Correlation (DIC) method was used to analyze the displacements in the vicinity of the jointed members of the chairs. Seat and backrest static load tests were carried out in order to verify if the chairs withstand standard loading requirements. Results indicated that the 3D printed connector exhibited equivalent mechanical performance as the traditional joint. The recorded displacement values of the chair with 3D-printed connectors were higher than those of the traditional chair reaching 0.6 mm on the X-axis and 1.1 mm on the Y-axis, without any failures under a maximum vertical load of approximately 15 kN applied to the seat. However, it successfully withstood the loads for seating and backrest standard tests, in accordance with EN 1728:2012, without any structural failure. This paper presents a new approach for the chair manufacturing sector, with potential applicability to other types of furniture. Full article
(This article belongs to the Section Mechanics of Materials)
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16 pages, 2188 KiB  
Article
Probing the Effects of Chemical Modifications on Anticoagulant and Antiproliferative Activity of Thrombin Binding Aptamer
by Antonella Virgilio, Daniela Benigno, Carla Aliberti, Ivana Bello, Elisabetta Panza, Martina Smimmo, Valentina Vellecco, Veronica Esposito and Aldo Galeone
Int. J. Mol. Sci. 2025, 26(1), 134; https://doi.org/10.3390/ijms26010134 - 27 Dec 2024
Cited by 1 | Viewed by 992
Abstract
Thrombin binding aptamer (TBA) is one of the best-known G-quadruplex (G4)-forming aptamers that efficiently binds to thrombin, resulting in anticoagulant effects. TBA also possesses promising antiproliferative properties. As with most therapeutic oligonucleotides, chemical modifications are critical for therapeutic applications, particularly to improve thermodynamic [...] Read more.
Thrombin binding aptamer (TBA) is one of the best-known G-quadruplex (G4)-forming aptamers that efficiently binds to thrombin, resulting in anticoagulant effects. TBA also possesses promising antiproliferative properties. As with most therapeutic oligonucleotides, chemical modifications are critical for therapeutic applications, particularly to improve thermodynamic stability, resistance in biological environment, and target affinity. To evaluate the effects of nucleobase and/or sugar moiety chemical modifications, five TBA analogues have been designed and synthesized considering that the chair-like G4 structure is crucial for biological activity. Their structural and biological properties have been investigated by Circular Dichroism (CD), Nuclear Magnetic Resonance (NMR), native polyacrylamide gel electrophoresis (PAGE) techniques, and PT and MTT assays. The analogue TBAB contains 8-bromo-2′-deoxyguanosine (B) in G-syn glycosidic positions, while TBAL and TBAM contain locked nucleic acid guanosine (L) or 2′-O-methylguanosine (M) in G-anti positions, respectively. Instead, both the two types of modifications have been introduced in TBABL and TBABM with the aim of obtaining synergistic effects. In fact, both derivatives include B in syn positions, exhibiting in turn L and M in the anti ones. The most appealing results have been obtained for TBABM, which revealed an interesting cytotoxic activity against breast and prostate cancer cell lines, while in the case of TBAB, extraordinary thermal stability (Tm approximately 30 °C higher than that of TBA) and an anticoagulant activity higher than original aptamer were observed, as expected. These data indicate TBAB as the best TBA anticoagulant analogue here investigated and TBABM as a promising antiproliferative derivative. Full article
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14 pages, 4895 KiB  
Article
Deep-Cavity Calix[4]naphth[4]arene Macrocycles: Synthesis, Conformational Features, and Solid-State Structures
by Paolo Della Sala, Veronica Iuliano, Margherita De Rosa, Carmen Talotta, Rocco Del Regno, Placido Neri, Silvano Geremia, Neal Hickey and Carmine Gaeta
Molecules 2024, 29(17), 4142; https://doi.org/10.3390/molecules29174142 - 31 Aug 2024
Cited by 3 | Viewed by 1869
Abstract
We recently introduced calix[n]naphth[m]arenes as a novel class of deep-cavity hybrid macrocycles constituted by phenol (n) and naphthalene (m) units. In this study, we report the synthesis, conformational analysis, spectroscopic properties, and solid-state structures of calix[4]naphth[4]arene (C4 [...] Read more.
We recently introduced calix[n]naphth[m]arenes as a novel class of deep-cavity hybrid macrocycles constituted by phenol (n) and naphthalene (m) units. In this study, we report the synthesis, conformational analysis, spectroscopic properties, and solid-state structures of calix[4]naphth[4]arene (C4N4) and its permethylated analog (C4N4-Me), thereby expanding the calix[n]naphth[m]arene family. C4N4 was synthesized through a 2 + 2 fragment coupling macrocyclization under acidic conditions, where the solvent played a crucial role in selectively forming the C4N4 derivative. The X-ray structure of C4N4 reveals a chair-like 1,2,3,4-alternate conformation characterized by two opposing 3/4-cone moieties stabilized by intramolecular hydrogen bonds. In contrast, the X-ray structure of C4N4-Me exhibits a 1,3,5,7-alternate conformation. Full article
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Article
Effects of a 12-Week Semi-Immersion Virtual Reality-Based Multicomponent Intervention on the Functional Capacity of Older Adults in Different Age Groups: A Randomized Control Trial
by Li-Ting Wang, Yung Liao, Shao-Hsi Chang and Jong-Hwan Park
Multimodal Technol. Interact. 2024, 8(8), 67; https://doi.org/10.3390/mti8080067 - 1 Aug 2024
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Abstract
Virtual reality (VR) exercise has been used as a strategy to promote physical health in older adults. Studies have revealed that the effects of exercise interventions vary across age groups. This study aimed to investigate the effects of a 12-week semi-immersion VR-based multicomponent [...] Read more.
Virtual reality (VR) exercise has been used as a strategy to promote physical health in older adults. Studies have revealed that the effects of exercise interventions vary across age groups. This study aimed to investigate the effects of a 12-week semi-immersion VR-based multicomponent exercise program on the functional fitness of young-old (65–73 years) and middle-old (74–85 years) adults. This study recruited two age groups (young-old adults, n = 49; middle-old adults, n = 37) and randomly assigned them to the experimental (EG) and control (CG) groups. EG participants performed a 75–90-min semi-immersion VR exercise routine twice weekly for 12 weeks, whereas CG participants maintained their original lifestyles without any alterations. The Senior Fitness Test was used to measure functional fitness by assessing upper- and lower-limb flexibility and muscle strength, cardiorespiratory fitness, and balance. EG participants exhibited greater improvements than their CG counterparts in certain functional fitness tests, specifically the Back Scratch, Arm Curl, 2-Minute Step, and 8-Foot Up-and-Go Tests. On comparing the age groups, a difference was exclusively noted in the effects of the Chair Sit-and-Reach Test. In the EG, the intervention significantly improved lower-body flexibility in young-old adults but elicited no such improvement in middle-old adults. Semi-immersion VR exercise improved the functional fitness of young-old and middle-old adults in the EG, with superior results in the former. Elucidating the impact of age-specific exercise interventions on functional capacity will help practitioners design age-specific exercise training content that enhances functional fitness in older adults of different ages. Full article
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