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Kyriaki Marina Lyra, Aggeliki Papavasiliou, Caroline Piffet, Lara Gumusboga, Jean-Michel Thomassin, Yana Marie, Alexandre Hoareau, Vincent Moulès, Javier Alcodori, Pau Camilleri Lledó, Albany Milena Lozano Násner, Jose Gallego, Elias Sakellis, Fotios K. Katsaros, Dimitris Tsiourvas and Zili Sideratou
Materials2026, 19(2), 346; https://doi.org/10.3390/ma19020346 (registering DOI) - 15 Jan 2026
The development of eco-friendly antimicrobial materials is essential for addressing antibiotic resistance, while reducing environmental impact. In this study, bio-derived anionic and cationic cellulose nanofibers (a-CNF and c-CNF) were employed as templating matrices for the in situ hydrothermal synthesis of cellulose/ZnO nanohybrids. Physicochemical
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The development of eco-friendly antimicrobial materials is essential for addressing antibiotic resistance, while reducing environmental impact. In this study, bio-derived anionic and cationic cellulose nanofibers (a-CNF and c-CNF) were employed as templating matrices for the in situ hydrothermal synthesis of cellulose/ZnO nanohybrids. Physicochemical characterization confirmed efficient cellulose functionalization and high-quality nanofibrillation, as well as the formation of uniformly dispersed ZnO nanoparticles (≈10–20 nm) strongly integrated within the cellulose network. The ZnO content was 30 and 20 wt. % for a-CNF/ZnO and c-CNF/ZnO, respectively. Antibacterial evaluation against Escherichia coli and Staphylococcus aureus revealed enhanced activity for both hybrids, with c-CNF/ZnO displaying the lowest MIC/MBC values (50/100 μg/mL). Antiviral assays revealed complete feline calicivirus inactivation at 100 μg/mL for c-CNF/ZnO, while moderate activity was observed against bovine coronavirus, highlighting the role of surface charge. Cytotoxicity assays on mammalian cells demonstrated high biocompatibility at antimicrobial concentrations. Life cycle assessment showed that c-CNF/ZnO exhibits a lower overall environmental burden than a-CNF/ZnO, with electricity demand being the main contributor, indicating clear opportunities for further reductions through process optimization and scale-up. Overall, these results demonstrate that CNF/ZnO nanohybrids effectively combine renewable biopolymers with ZnO antimicrobial functionality, offering a sustainable and safe platform for biomedical and environmental applications.
Full article
Background/Objectives: Post-COVID-19 condition (PCC) remains poorly characterized beyond two years, particularly among intensive care unit (ICU) survivors. We aimed to describe the prevalence, persistence, and late consequences of PCC up to 32 months after discharge in an ICU cohort. Methods: This single-center longitudinal
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Background/Objectives: Post-COVID-19 condition (PCC) remains poorly characterized beyond two years, particularly among intensive care unit (ICU) survivors. We aimed to describe the prevalence, persistence, and late consequences of PCC up to 32 months after discharge in an ICU cohort. Methods: This single-center longitudinal cohort included 170 adults with confirmed SARS-CoV-2 infection admitted to an ICU in Cáceres (Spain) between March 2020 and March 2021. 94 survivors entered follow-up at discharge and 3, 6, 12, 18, 24, and 32 months. PCC manifestations were grouped into five organ system domains (respiratory, cardiovascular, renal, infectious, and musculoskeletal/neuromuscular) and recorded only when supported by clinician-confirmed diagnoses or diagnostic tests. Prevalence at each visit, persistence, and new onset of manifestations between 3 and 6 months, and the cumulative incidence of new chronic diseases between 18 and 32 months were estimated with 95% confidence intervals. Results: Any PCC manifestation was almost universal at discharge (96.8% [95% CI, 91.1–98.9]) and remained high at 12 months (85.2% [95% CI, 76.3–91.2]), declining to 48.6% at 24 months and 25.7% at 32 months. Respiratory manifestations predominated early and were largely resolved by 32 months, whereas musculoskeletal/neuromuscular involvement remained relatively stable. From 18 to 32 months, 36.5% (95% CI, 26.4–47.9) of survivors developed at least one chronic condition, most frequently cardiovascular disease (14.9% [95% CI, 8.5–24.7]). Conclusions: Long-term PCC manifestations and incident chronic diseases are common among ICU COVID-19 survivors, underscoring the need for prolonged follow-up and post-ICU care.
Full article
Mathematical models for infectious diseases, particularly autonomous ODE models, are generally known to possess simple dynamics, often converging to stable disease-free or endemic equilibria. This paper investigates the dynamic consequences of a crucial, yet often overlooked, component of pandemic response: the saturation of
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Mathematical models for infectious diseases, particularly autonomous ODE models, are generally known to possess simple dynamics, often converging to stable disease-free or endemic equilibria. This paper investigates the dynamic consequences of a crucial, yet often overlooked, component of pandemic response: the saturation of public health testing. We extend the standard SIR model to include compartments for ‘Confirmed’ (C) and ‘Monitored’ (M) individuals, resulting in a new SICMR model. By fitting the model to U.S. COVID-19 pandemic data (specifically the Omicron wave of late 2021), we demonstrate that capacity constraints in testing destabilize the testing-free endemic equilibrium (). This equilibrium becomes an unstable saddle-focus. The instability is driven by a sociological feedback loop, where the rise in confirmed cases drive testing effort, modeled by a nonlinear Holling Type II functional response. We explicitly verify that the eigenvalues for the best-fit model satisfy the Shilnikov condition (), demonstrating the system possesses the necessary ingredients for complex, chaotic-like dynamics. Furthermore, we employ Stochastic Differential Equations (SDEs) to show that intrinsic noise interacts with this instability to generate ’noise-induced bursting,’ replicating the complex wave-like patterns observed in empirical data. Our results suggest that public health interventions, such as testing, are not merely passive controls but active dynamical variables that can fundamentally alter the qualitative stability of an epidemic.
Full article
Background: Depressive symptoms are frequent sequelae of COVID-19 and may remain unrecognized in older outpatients, particularly those with post-COVID syndrome. The objective of the current study was to assess the under-detection of depressive symptoms in older ambulatory patients and to examine its relationship
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Background: Depressive symptoms are frequent sequelae of COVID-19 and may remain unrecognized in older outpatients, particularly those with post-COVID syndrome. The objective of the current study was to assess the under-detection of depressive symptoms in older ambulatory patients and to examine its relationship with post-COVID syndrome status. Methods: We conducted an observational outpatient cohort study of adults aged 60–89 years with prior SARS-CoV-2 infection (N = 85), recruited at two city polyclinics. Depressive symptoms were assessed through three detection channels: spontaneous complaint during the visit, a standardized direct question about current depressive symptoms, and the 15-item Geriatric Depression Scale (GDS-15). Agreement between complaint and direct question was evaluated using Cohen’s κ and McNemar’s test. Screening performance of complaint and direct question was assessed against GDS-15 thresholds (≥5; sensitivity analysis ≥ 6). Associations between post-COVID syndrome status and binary depressive-symptom indicators were expressed as risk ratios (RRs). Results: Spontaneous complaints missed a substantial proportion of cases: among complaint-negative patients, 18.3% (15/82) reported depressive symptoms on the direct question (κ = 0.149; McNemar p = 0.00052). Against GDS-15 ≥ 5, complaint sensitivity was 10.3% with specificity 100.0% (F1 = 0.19), whereas the direct question showed higher sensitivity (34.5%) with specificity 87.5% (F1 = 0.43). Using the alternative threshold GDS-15 ≥ 6, complaint sensitivity was 15.0% with specificity 100.0% (F1 = 0.26), and direct question sensitivity was 45.0% with specificity 87.7% (F1 = 0.49). A positive response to the direct question was more frequent in patients with post-COVID syndrome than in controls (RR = 2.70 (1.04–7.00)); stratified estimates suggested higher RRs in patients ≤ 75 years (RR = 4.55 (1.08–19.10)) and in women (RR = 2.67 (1.04–6.83)), with limited precision due to sparse events. Conclusions: In older post-COVID outpatients, reliance on spontaneous complaints leads to marked under-detection of GDS-15 screen-positive depressive symptoms. A standardized direct question improves initial case-finding but does not replace a validated screening scale; a stepped approach (brief direct question followed by a scale when indicated) may be warranted.
Full article
Background: Intentional occlusion of the internal iliac artery (IIA) during endovascular repair of aorto-iliac aneurysms may predispose patients to pelvic ischemic complications such as gluteal claudication, erectile dysfunction, and bowel ischemia. Iliac branch devices (IBDs) have been developed to preserve hypogastric perfusion.
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Background: Intentional occlusion of the internal iliac artery (IIA) during endovascular repair of aorto-iliac aneurysms may predispose patients to pelvic ischemic complications such as gluteal claudication, erectile dysfunction, and bowel ischemia. Iliac branch devices (IBDs) have been developed to preserve hypogastric perfusion. E-Liac (Artivion/Jotec) is one of the latest modular IBDs yet reports on mid-term performance are limited to small single-center cohorts with short follow-up. The CAMpania PugliA bRanch IliaC (CAMPARI) study is a multicenter investigation of E-Liac outcomes. Methods: A retrospective observational cohort study was conducted across five Italian vascular centers. All consecutive patients undergoing E-Liac implantation for aorto-iliac or isolated iliac aneurysms between January 2015 and December 2024 were identified from prospectively maintained registries. Inclusion criteria comprised elective or urgent endovascular repair of aorto-iliac aneurysms in which an adequate distal sealing zone was not available without covering the IIA and suitability for the E-Liac device according to its instructions for use (IFU). Patients with a life expectancy < 1 year or hostile anatomy incompatible with the IFU were excluded. The primary end point was freedom from branch instability (occlusion/stenosis, kinking, or detachment of the bridging stent). Secondary end points included freedom from any endoleak, freedom from device-related reintervention, freedom from gluteal claudication, aneurysm-related and all-cause mortality, acute renal failure, and sac regression > 5 mm. Results: A total of 69 consecutive patients (68 male, 1 female, median age 72.0 years) received 74 E-Liac devices, including 5 bilateral implantations. The mean infrarenal aortic diameter was 45 mm and the mean CIA diameter 34 mm; 14 patients (20.0%) had a concomitant IIA aneurysm (>20 mm). Concomitant fenestrated or branched aortic repair was performed in 23% of procedures. Two patients received a standalone IBD without implantation of a proximal aortic endograft. Technical success was achieved in 71/74 cases (96.0%); three failures occurred due to inability to catheterize the IIA. Distal landing was in the main IIA trunk in 58 cases and in the posterior branch in 13 cases. Over a median follow-up of 18 (6; 36) months, there were four branch instability events (5.4%): three occlusions and one bridging stent detachment. Seven patients (9.5%) developed endoleaks (one type Ib, two type II, two type IIIa, and two type IIIc). Five patients (6.8%) required reintervention, and five (6.8%) reported gluteal claudication. There were seven all-cause deaths (10%), none within 30 days or related to aneurysm rupture; causes included COVID-19 pneumonia, acute coronary syndrome, melanoma, gastric cancer, and stroke. No acute renal or respiratory failure occurred. Kaplan–Meier analysis showed 92% (95% CI 77–100) freedom from branch instability in the main-trunk group and 89% (60–100) in the posterior-branch group (log-rank p = 0.69). Freedom from any endoleak at 48 months was 87% (95% CI 75–95), and freedom from reintervention was 93% (95% CI 83–98). Conclusions: In this multicenter cohort, the E-Liac branched endograft demonstrated high technical success and favorable early–mid-term outcomes. Preservation of hypogastric perfusion using E-Liac was associated with low rates of branch instability, endoleak, and reintervention, with no 30-day mortality or aneurysm-related deaths. These findings support the safety and efficacy of E-Liac for aorto-iliac aneurysm management, although larger prospective studies with longer follow-up are needed.
Full article
The emergence of SARS-CoV-2, the etiological agent of COVID-19, has resulted in widespread global infection and millions of deaths. Viral entry is initiated by the interaction between the viral spike (S) protein and the host cell receptor ACE2, followed by TMPRSS2-mediated proteolytic activation
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The emergence of SARS-CoV-2, the etiological agent of COVID-19, has resulted in widespread global infection and millions of deaths. Viral entry is initiated by the interaction between the viral spike (S) protein and the host cell receptor ACE2, followed by TMPRSS2-mediated proteolytic activation that facilitates membrane fusion. Bitter melon (Momordica charantia L., MC), a traditional medicinal and edible plant widely used in tropical Asia, possesses notable anti-inflammatory, antioxidant, antitumor, and hypoglycemic properties. In this study, the ethanol extract of bitter melon (EMC) markedly downregulated ACE2 and TMPRSS2 expression in both in vitro and in vivo models without inducing cytotoxicity. Furthermore, phytochemicals isolated from EMC—including p-coumaric acid, rutin, and quercetin—exhibited comparable inhibitory effects. These results indicate that EMC and its bioactive constituents may interfere with SARS-CoV-2 entry by modulating the ACE2/TMPRSS2 axis, highlighting their potential as natural adjuncts for COVID-19 prevention or management.
Full article
The first webinar in the series, held on 17 April 2020, saw both Prof. Dr. Antoine Flahault, Director of the Institute of Global Health, University of Geneva, Switzerland, and Prof. Dr. Evelyne Bischof, Associate Professor, Shanghai University of Medicine and Health Sciences, Shanghai, China and Research physician, University Hospital of Basel, Basel, Switzerland speak on this topic.
The second webinar in the series, entitled “Coronaviruses: history, replication, innate immune antagonism”, saw Prof. Dr. Susan R. Weiss, Professor of Microbiology, Perelman School of Medicine, University of Pennsylvania speak on this topic.
WEBINAR 3: Could the COVID-19 Crisis be the Opportunity to Make Cities Carbon Neutral, Liveable and Healthy
The third webinar in this series was presented by Prof. Dr. Mark Nieuwenhuijsen, a world leading expert in environmental exposure assessment, epidemiology, and health risk/impact assessment with a strong focus and interest on healthy urban living.
WEBINAR 4: COVID-19 - Global Supply Chains and the SDGs
For the fourth webinar of this series, Prof. Dr. Max Bergman, Dr. Dorothea Schostok and Prof. Dr. Patrick Paul Walsh gave a presentation on Global Supply Chains and the SDGs.
WEBINAR 5: The New Role of Family Physicians in Times of COVID-19
The fifth webinar of the COVID-19 Series saw Prof. Dr. Christos Lionis discuss the new role of family physicians that emerged during the COVID-19 pandemic.
WEBINAR 6: Survey on Symptoms/Signs, Protective Measures, Level of Awareness and Perception Regarding COVID-19 Outbreak among Dentists
In the sixth webinar of this series, Prof. Dr. Guglielmo Campus and Prof. Dr. Maria Grazia present and discuss the risk and the preventions that can and should be taken by dentists during this pandemic.
WEBINAR 7: Living with COVID-19: An Early Intervention Therapeutic Strategy to Control the Pandemic
The seventh webinar of the COVID-19 series, Dr. Hamid Merchant discussed the different therapeutic strategies that can be adopted in the early stages of the infection.
WEBINAR 8: Impact of COVID-19 on Routine Immunization, Reproduction and Pregnancy Outcome
For the eighth COVID-19 webinar, Prof. Dr. Jon Øyvind Odland discussed the effect that COVID-19 seems to have on pregnant women; whereas Prof. Dr. Giovanni Gabutti discussed the role of routine immunization as a way of fighting COVID-19.
