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Human collagen-based hydrogel with zinc oxide nanoparticles for articular cartilage engineering

2026-04-08T14:30:19Z

Title: Human collagen-based hydrogel with zinc oxide nanoparticles for articular cartilage engineering Authors: Cobzac, Vitalie; Cojocari, Ștefan; Jian, Mariana; Stoian, Alina; Nacu, Ana-Maria; Motelica, Ludmila; Trusca, Roxana; Ficai, Anton; Nacu, Viorel Abstract: Introduction. Articular cartilage tissue engineering has a long history of using three-dimensional matrices seeded with cells of chondrogenic potential. Recent studies show that chondrogenesis is influenced not only by growth factors, but also by the biochemical microenvironment, including ions such as Zn²⁺ and Cu²⁺. Materials and methods: With approval from the Ethics Committee of Nicolae Testemitanu State University of Medicine and Pharmacy and under a collaboration agreement with the Human Tissue Bank of the Clinical Hospital of Traumatology and Orthopaedics, articular cartilage was collected from a donated femoral head, along with processed umbilical-placental complex. Collagen hydrogels (3 mg/ml) were prepared in 24-well plates containing ZnO NPs (<50 nm; Sigma-Aldrich, USA) at 0 (control), 1, 10, 20, 40, 60, 80, and 100 µg/ml (n=4). Their elastic modulus (EM) was measured using a TX-BLM probe and a TX-700 texture analyzer (Lamy Rheology, France). For viability testing, human chondrocytes (1×105 cells/ml) were cultured on hydrogels containing 0 (control), 10, 50, or 100 µg/ml ZnO NPs. Resazurin (10 µg/ml; Acros TFS, Belgium) was used as the viability reagent, and blanks without cells were prepared for each concentration and control group (n=3). Measurements were performed at 24, 48, and 72 hours after 6 h incubation at 37°C and 5% CO₂. Absorbance was recorded at 570 and 600 nm using a Synergy H3 spectrophotometer (BioTek, USA). Results and Conclusions. ZnO NPs concentration markedly affected the mechanical properties of the hydrogels. Significant differences were found between the control group (470.73 ±38.00 N/m²) and most ZnO-loaded groups. EM was significantly reduced at 60, 80, and 100 µg/ml ZnO (p <0.05), whereas at 1, 10, and 20 µg/ml it was significantly higher than in the control group (p <0.05). No significant difference was observed at 40 µg/ml (p >0.05). The resazurin assay showed a dosedependent effect of ZnO NPs on chondrocyte viability. The highest viability was recorded at 10 µg/ml ZnO, remaining above 70% over three consecutive days, while higher concentrations caused a marked decrease in viability (p < 0.05). Therefore, 10 µg/ml ZnO appears to be the most promising concentration, offering a favorable balance between mechanical strength and cell viability. Description: Acknowledgements: research founded by young researchers project #25.80012.8007.05TC

Biocompatibility and tissue integration of endovascular implants used in intracranial aneurysms

2026-04-08T14:20:17Z

Title: Biocompatibility and tissue integration of endovascular implants used in intracranial aneurysms Authors: Ciobanu, Lorina; Preguza, Ion; Chira, Inga; Pîrțac, Mihai Abstract: Introduction: In the modern management of intracranial aneurysms, the endovascular method has become a more frequently used method of treatment, especially the use of flow-diverters (FD) and coil embolization devices. These implants act as intravascular scaffolds that alter the hemodynamic and the biological response at the aneurysm affected artery interface. One of the critical components of the long-term success of this method is the biocompatibility and tissue integration of these implants. The aim of the study: Synthesizing current evidence on the host-implant interaction and evaluating the impact of the material and surface modifications on the healing process in endovascular treatment of intracranial aneurysms. Materials and methods: Research of scientific literature, from electronic databases such as PubMed, Web of Science and ScienceDirect, published in the last decade that addresses biocompatibility, endothelialization and tissue integration of intracranial aneurysms endovascular treatment. Results: Studies have shown a correlation between in-stent thrombosis, stenosis and the use of phenoxhydrophilic polymer-coated devices, in 77.6% of cases, compared to 66.2% in the use of flowdiverters. The next generation of FD is the bioresorbable type, which has shown reduction of chronic inflammation, side branch occlusion, device induced stenosis and imaging artefacts, while increasing the use in pediatric applications. Poly-L-lactic acid-coated magnesium coated FD and bare magnesium coated FD have excellent biocompatibility, but the bioresorption in case of the Poly-L-lactic acidcoated magnesium FD was delayed. Studies have also shown no significant difference between fibrinbased coated and non-coated flow-diverters, both having similar blood and tissue compatibility. However, current data regarding the relationship between endovascular devices, endothelialization and biocompatibility has largely been derived from preclinical animal models, therefore further studies are necessary. Conclusion: Overall, device material and surface modification significantly influence biocompatibility and vascular healing in endovascular implants of intracranial aneurysms, with bioresorbable flow diverters showing promising reductions in chronic inflammation and device-related complications. However, as most evidence derives from preclinical models, well-designed prospective human studies are essential to validate these biological advantages and their impact on long-term clinical outcomes.

Efficacy and complications of autologous hematopoietic stem cell transplantation in multiple sclerosis

2026-04-08T14:15:38Z

Title: Efficacy and complications of autologous hematopoietic stem cell transplantation in multiple sclerosis Authors: Chira, Inga; Capcelea, Svetlana; Pîrțac, Mihail; Ciobanu, Lorina Abstract: Introduction. Autologous hematopoietic stem cell transplantation (AHSCT) is a therapeutic strategy with curative potential for relapsing-remitting multiple sclerosis (RRMS) [1]. AHSCT is a modern alternative to disease-modifying therapies, since a low therapeutic response has been observed in RRMS patients [6]. The action mechanism is based on the immunosuppression of autoreactive lymphocytes to subsequently remodel the immune response through self-hematopoietic stem cells [1, 3], restoring immune tolerance and suppressing the inflammatory response [2]. Materials and methods. For this study, was performed a search of the specialized scientific literature from 2019-2025, the articles were identified through the search engine PubMed, Google Scholar. Results. A prevalence of 68%-88% of patients undergoing AHSCT maintained no evidence of disease activity: NEDA-3 (no relapses, no magnetic resonance imaging activity and no MS progression) in the following 3-5 years after therapy [4, 8]. The efficacy rate is 86.9-91.3% due to the absence of clinical relapses at 5 years after transplantation [1, 2]. The success rate is higher in patients under 45-50, with an expanded disability status scale (EDSS) <5.5-6 [4], and disease duration of less than 5-10 years, thus having a higher chance of remission [1]. The mortality is 2.1% [2]. To confirm the biological efficacy, cerebrospinal fluid is extracted, and it has been observed that CXCL13 decreases in the first year and sCD27 normalizes over the next two years [6]. Complications vary depending on individual tolerance and 17% of patients suffer from Uhthoff's phenomenon in the first 60 days [4], myelosuppression in the first 100 days [7], neutropenia (58%-70%) [8], bacterial sepsis, pneumonia, urinary tract infections, hemorrhagic cystitis, dyspeptic disorders and venous thrombosis [4]. Autoimmune thyroiditis or immune thrombocytopenia occur in 4-6%, Epstein-Barr virus and cytomegalovirus are reactivated in 80% of cases, and there have been recorded oncological risks such as breast cancer, glioblastoma, prostate cancer post-AHSCT [4]. Arrhythmias, renal failure and infertility are found in a minor percentage [5, 7]. Conclusions. With over 80% efficacy, AHSCT is the most effective treatment for RRMS, and despite adverse reactions, this therapy offers optimal therapeutic prospects for patients with active forms of MS.

Evaluation of the therapeutic potential of kaempferol-loaded bionanocomposites in corneal neovascularization

2026-04-08T13:22:31Z

Title: Evaluation of the therapeutic potential of kaempferol-loaded bionanocomposites in corneal neovascularization Authors: Chiaburu, Andrei; Corețchi, Ianoș; Zaltariov, Mirela-Fernanda; Beșliu, Alina; Ciubotaru, Bianca-Iulia; Casian, Ana; Casian, Igor; Ceban, Cornelia; Pavlovschi, Ecaterina Abstract: Introduction. The cornea is the transparent anterior structure of the eyeball, characterized by the absence of blood vessels, a condition essential for maintaining its optical function. Among ocular diseases, corneal neovascularization is a major cause of impaired visual acuity and may progress to severe vision loss or blindness. Aim of study. To analyze recent studies regarding the therapeutic potential of kaempferol-loaded bionanocomposites for the treatment of corneal neovascularization, with particular emphasis on their pharmacokinetic advantages and prospects for clinical application. Methods and materials. The study is based on the analysis of bibliographic sources indexed in the PubMed and Google Scholar databases published between 2018 and 2025. A total of 40 scientific publications were analyzed. Results. Kaempferol, a flavonoid-rich plant compound, is known for its antiangiogenic properties and is of interest as a potential therapeutic agent for inhibiting the formation of vascular neoformations at the corneal level. However, the direct administration of kaempferol is considerably limited by anatomical barriers and low bioavailability. In this context, nanomedicine can improve the pharmacological potential of kaempferol and offer minimally invasive therapeutic strategies. The use of bionanocomposites loaded with kaempferol and nanoparticles of ZnO, SiO₂ and Ag can contribute to increasing the bioavailability of hydrophobic kaempferol, significantly reducing abnormal blood vessel formation, inflammation, and angiogenic factors such as VEGF by inhibiting cell migration. The integration of nanoparticles into the composition of bionanocomposites can provide additional therapeutic advantages, including the reduction of oxidative stress and attenuation of the inflammatory response. In addition, ZnO and Ag nanoparticles exhibit antimicrobial properties that may improve the therapeutic potential and support ocular regeneration. Conclusion. The therapeutic potential of kaempferol-loaded bionanocomposites in corneal regeneration is immense due to the multitude of benefits. However, further investigations are needed to design and optimize kaempferol-functionalized bionanocomposites that allow for controlled release of the compound, protect its chemical stability, and increase its bioavailability at the corneal level, thus maximizing therapeutic efficacy.