Search Results (606)

Background and Objectives: Despite significant advances in surgical techniques and perioperative care, major adverse cardiovascular events (MACE) remain a leading cause of postoperative morbidity and mortality in patients undergoing coronary artery bypass grafting and/or aortic valve replacement. Accurate preoperative risk stratification is essential yet often limited by models that overlook atrial mechanics and underutilized biomarkers. Materials and Methods: This study aimed to develop an interpretable machine learning model for predicting perioperative MACE by integrating clinical, biochemical, and echocardiographic features, with a particular focus on novel physiological markers. A retrospective cohort of 131 patients was analyzed. An Extreme Gradient Boosting (XGBoost) classifier was trained on a comprehensive feature set, and SHapley Additive exPlanations (SHAPs) were used to quantify each variable’s contribution to model predictions. Results: In a stratified 80:20 train–test split, the model initially achieved an AUC of 1.00. Acknowledging the potential for overfitting in small datasets, additional validation was performed using 10 independent random splits and 5-fold cross-validation. These analyses yielded an average AUC of 0.846 ± 0.092 and an F1-score of 0.807 ± 0.096, supporting the model’s stability and generalizability. The most influential predictors included total atrial conduction time, mitral and tricuspid annular orifice areas, and high-density lipoprotein (HDL) cholesterol. These variables, spanning electrophysiological, structural, and metabolic domains, significantly enhanced discriminative performance, even in patients with preserved left ventricular function. The model’s transparency provides clinically intuitive insights into individual risk profiles, emphasizing the significance of non-traditional parameters in perioperative assessments. Conclusions: This study demonstrates the feasibility and potential clinical value of combining advanced echocardiographic, biochemical, and machine learning tools for individualized cardiovascular risk prediction. While promising, these findings require prospective validation in larger, multicenter cohorts before being integrated into routine clinical decision-making. Full article

Background: Digital technologies offer innovative opportunities for recovering and maintaining intellectual and mental health. The use of a multitask approach that combines motor component with various cognitive tasks in a virtual environment can optimize cognitive and physical functions and improve the quality of life of cardiac surgery patients. This study aimed to localize current sources of theta and alpha power in patients who have undergone virtual multitask training (VMT) and a control group in the early postoperative period of coronary artery bypass grafting (CABG). Methods: A total of 100 male CABG patients (mean age, 62.7 ± 7.62 years) were allocated to the VMT group (n = 50) or to the control group (n = 50). EEG was recorded in the eyes-closed resting state at baseline (2–3 days before CABG) and after VMT course or approximately 11–12 days after CABG (the control group). Power EEG analysis was conducted and frequency-domain standardized low-resolution tomography (sLORETA) was used to assess the effect of VMT on brain activity. Results: After VMT, patients demonstrated a significantly higher density of alpha-rhythm (7–9 Hz) current sources (t > −4.18; p < 0.026) in Brodmann area 30, parahippocampal, and limbic system structures compared to preoperative data. In contrast, the control group had a marked elevation in the density of theta-rhythm (3–5 Hz) current sources (t > −3.98; p < 0.017) in parieto-occipital areas in comparison to preoperative values. Conclusions: Virtual reality-based multitask training stimulated brain regions associated with spatial orientation and memory encoding. The findings of this study highlight the importance of neural mechanisms underlying the effectiveness of multitask interventions and will be useful for designing and conducting future studies involving VR multitask training. Full article

Using ultra-short dental implants is a promising alternative to extensive bone grafting procedures for patients with atrophic posterior mandibles and vertical bone loss. However, the amount of insertion torque (IT) applied during implant placement significantly influences stress distribution in the peri-implant bone, which affects implant stability and long-term success. Materials and Methods: This study used finite element analysis (FEA) to examine how different insertion torques (35 N·cm and 75 N·cm) affect stress distribution in cortical and trabecular bone types D2 and D4 surrounding ultra-short implants. Von Mises equivalent stress values were compared with ultimate bone strength thresholds to evaluate the potential for microdamage during insertion. Results: The findings demonstrate that increasing IT from 35 N·cm to 75 N·cm led to a significant increase in peri-implant bone stress. Specifically, cortical bone stress in D4 bone increased from approximately 79 MPa to 142 MPa with higher IT, exceeding physiological limits and elevating the risk of microfractures and bone necrosis. In contrast, lower IT values kept stress within safe limits, ensuring optimal primary stability without damaging the bone. These results underscore the need to strike a balance between achieving sufficient implant stability and avoiding mechanical trauma to the surrounding bone. Conclusions: Accurate control of insertion torque during the placement of ultra-short dental implants is crucial to minimize bone damage and promote optimal osseointegration. Excessive torque, especially in low-density bone, can compromise implant success by inducing excessive stress, thereby increasing the risk of early failure. Full article

The increasing number of acetabular revision total hip arthroplasties requires the evaluation of alternative materials in addition to established standards using a defined animal experimental defect that replicates the human acetabular revision situation as closely as possible. Defined bone defects in the load-bearing area of the acetabulum were augmented with various materials in an ovine periacetabular defect model (Group 1: NanoBone^® (artificial hydroxyapatite-silicate composite; Artoss GmbH, Germany); Group 2: autologous sheep cancellous bone; Group 3: Tutoplast^® (processed allogeneic sheep cancellous bone; Tutogen Medical GmbH, Germany)) and bridged with an acetabular reinforcement ring of the Ganz type. Eight months after implantation, a μ-CT examination (n = 8 animals per group) was performed. A μ-CT analysis of the contralateral acetabula (n = 8, randomly selected from all three groups) served as the control group. In a defined volume of interest (VOI), bone volume (BV), mineral volume (MV), and bone substitute volume (BSV), as well as the bone surface (BS) relative to the total volume (TV) and the surface-to-volume ratio (BS/BV), were determined. To assess the bony microarchitecture, trabecular thickness (Tb.Th), trabecular separation (Tb.Sp), and trabecular number (Tb.N), as well as connectivity density (Conn.D), the degree of anisotropy (DA), and the structure model index (SMI), were evaluated. The highest BV was observed for NanoBone^® (Group 1), which also showed the highest proportion of residual bone substitute material in the defect. This resulted in a significant increase in BV/TV with a significant decrease in BS/BV. The assessment of the microstructure for Groups 2 and 3 compared to Group 1 showed a clear approximation of Tb.Th, Tb.Sp, Tb.N, and Conn.D to the microstructure of the control group. The SMI showed a significant decrease in Group 1. All materials demonstrated their suitability by supporting biological defect reconstruction. NanoBone^® showed the highest rate of new bone formation; however, the microarchitecture indicated more advanced bone remodeling and an approximate restoration of the trabecular structure for both autologous and allogeneic Tutoplast^® cancellous bone when using the impaction bone grafting technique. Full article

Background: Maxillofacial bone defects present considerable challenges in oral and reconstructive surgery. While autologous bone grafts are the gold standard, their limitations, such as donor site morbidity and limited availability, have driven the search for alternative biomaterials. SmartBone^®, a xeno-hybrid graft, offers potential advantages due to its bioactivity and remodeling capacity. Methods: This analysis of a series of clinical cases, evaluated the performance of SmartBone^® in 10 patients presenting with various maxillofacial bone defects. The patient follow-up period spanned from 2017 to 2019, with a maximum duration of 30 months. Bone grafting was performed, and integration was monitored using Cone-Beam Computed Tomography at multiple timepoints. Bone density changes (ΔCT values) in selected anatomical sites were analyzed to assess graft transformation and integration. Results: SmartBone^® supported effective bone regeneration and selective remodeling in all cases. One patient required a revision procedure, after which successful integration was observed. Cellular colonization began within weeks, with complete remodeling into mature bone occurring between 6–12 months. Evidence of cortical wall resorption and reformation on the graft’s external surface confirmed this transformation. ΔCT values progressively aligned with native bone densities, indicating structural and functional integration. Conclusions: SmartBone^® demonstrates strong osteointegrative and site-specific remodeling capabilities, offering a reliable and predictable alternative for maxillofacial bone reconstruction. The study presents several limitations, including the small sample size, inter-patient variability, possible imaging artifacts due to metallic elements in Cone-Beam Computed Tomography scans and the lack of histological confirmation. Full article

Background: Histological and immunohistochemical analyses of adipose tissue are essential for evaluating the quality and functionality of lipoaspirates in regenerative medicine and fat grafting procedures. These methods provide insights into tissue viability, cellular subtypes, and extracellular matrix (ECM) composition—all factors influencing graft retention and clinical outcomes. Purpose: This scoping review aims to summarize the most commonly used staining methods and their applications in the histology and immunohistochemistry of adipose tissue. By exploring qualitative and quantitative markers, we seek to guide researchers in selecting the appropriate methodologies for addressing experimental and translational research. Methods: A systematic search was conducted using PubMed, Ovid, and the Cochrane Library databases from inception to 2024, employing Boolean operators (“lipoaspirate” OR “fat graft” OR “gauze rolling” OR “decantation” OR “coleman fat” OR “celt” OR “nanofat” OR “lipofilling” OR “human fat” AND “histol*”). Studies were included if they utilized histology or immunohistochemistry on undigested human adipose tissue or its derivatives. The inclusion criteria focused on peer-reviewed, English-language studies reporting quantitative and qualitative data on adipose tissue markers. Results: Out of 166 studies analyzed, hematoxylin–eosin (H&E) was the most frequently employed histological stain (152 studies), followed by Masson Trichrome and Sudan III. Immunohistochemical markers such as CD31, CD34, and perilipin were extensively used to distinguish stromal vascular fraction (SVF) cells, adipocytes, and inflammatory processes. Studies employing semiquantitative scoring demonstrated enhanced comparability, particularly for fibrosis, necrosis, and oil cyst evaluation. Quantitative analyses focused on SVF cell density, mature adipocyte integrity, and ECM composition. Methodological inconsistencies, particularly in preparation protocols, were observed in 25 studies. Conclusions: This review highlights the critical role of histological and immunohistochemical methods in adipose tissue research. H&E staining remains the cornerstone for general tissue evaluation in the clinical context, while specialized stains and immunohistochemical markers allow for detailed analyses of specific cellular and ECM components in experimental research. Standardizing preparation and evaluation protocols will enhance interstudy comparability and support advancements in adipose tissue-based therapies. Full article

Grapevine root distribution and density influence mineral and water absorption and are affected by soil management and the use of cover crops. This study, conducted in a ten-year-old commercial Mediterranean vineyard with desiccant-managed inter-rows, compares the effects of three different soil management practices—minimum tillage (MT), spontaneous natural covering (NC), and a commercial grass mixture (GM)—on root development in Montepulciano vines grafted onto Kober 5BB rootstocks. Root length, diameter, and weight across different soil layers were analyzed by digging trenches. The results show that thin roots, primarily responsible for water and nutrient absorption, ensure greater soil volume exploration, while medium-to-large roots contribute mainly to root biomass. The presence of cover crops reduces root development in the upper soil layers due to competition with herbaceous species; however, this promotes deeper root exploration and increases the total root length per plant. In the deeper soil layers, root growth is limited by higher soil compaction. Tillage enhances the development of medium-to-large roots and increases the total root biomass per plant. In conclusion, soil management influences vine root development, and competition from cover crops stimulates the growth of absorbing roots in deeper soil layers. Full article

This study evaluated the biological performance in vitro of two 3D-printed hydroxyapatite (HA) and polylactic acid (PLA) composite scaffolds with two different infill densities (50% [HA-PLA50] and 70% [HA-PLA70]). Comparative analysis using MG-63 cell cultures evaluated the following: (1) integrity after exposure to various sterilization methods; (2) cell viability; (3) morphological characteristics; (4) cell proliferation; (5) cytotoxicity; (6) gene expression; and (7) protein synthesis. Ultraviolet radiation was the preferred sterilization method. Both scaffolds maintained adequate cell viability and proliferation over 7 days without significant differences in cytotoxicity. Notably, HA-PLA50 scaffolds demonstrated superior osteogenic potential, showing a significantly higher expression of collagen type I (COL1A1) and an increased synthesis of interleukins 6 and 8 (IL-6, IL-8) compared to HA-PLA70 scaffolds. While both scaffold types supported robust cell growth, the HA-PLA50 formulation exhibited enhanced bioactivity, suggesting a potential advantage for bone tissue engineering applications. These findings provide important insights for optimizing 3D-printed bone graft substitutes. Full article

Nanomedicine is rapidly evolving, with tailored nanoparticles enabling precise cellular-level interventions. Despite significant advances, challenges, such as rapid clearance and off-target effects, hinder the clinical translation of many nanosystems. Among the available nanoplatforms, gold nanoparticles (AuNPs) stand out due to their unique surface chemistry, low toxicity, and excellent biocompatibility. In this work, we present a multi-level computational investigation of ultra-small AuNPs coated with non-conventional amphiphilic polymer chains via atomistic and coarse-grained molecular dynamics. Through high-level-resolution atomistic simulations, we investigate how variations in grafting density impact the collective behaviors of these amphiphilic polymer chains within the coating by quantifying relevant conformational, structural, and energetic descriptors, such as the radius of gyration, terminal group presentation, polymer coating thickness, brush height, and solvation energy. Our results reveal a conformational shift of polymer chains from coiled to stretched as grafting density increases, with a direct effect on the polymer conformational regime, terminal group presentation, and coating thickness. In parallel, we further benchmark low-level coarse-grained models using the atomistic data as a reference, demonstrating their ability to correctly reproduce the atomistic trends. This computational investigation reveals how key descriptors vary with grafting density and provides the tools for conducting similar studies on broader time and length scales, thereby advancing the rational design of nanosystems for nanomedicine. Full article

This study aims to improve the performance of wood–plastic composites (WPCs) composed of cotton stalk powder and residual film particles. Additionally, it aims to promote the efficient utilization of cotton stalk biochar. The composites were prepared using modified cotton stalk biochar and xylem powder as the matrix, maleic anhydride grafted high-density polyethylene (MA-HDPE) as the coupling agent, and polyethylene (PE) residual film particles as the filler. The WPCs were fabricated through melt blending using a twin-screw extruder. Mechanical properties were evaluated using a universal testing machine and texture analyzer, Shore D hardness was measured using a durometer, and microstructure was analyzed using a high-resolution digital optical microscope. A systematic investigation was conducted on the effect of biochar content on material properties. The results indicated that modified biochar significantly enhanced the mechanical and thermal properties of the WPCs. At a biochar content of 80%, the material achieved optimal performance, with a hardness of 57.625 HD, a bending strength of 463.159 MPa, and a tensile strength of 13.288 MPa. Additionally, thermal conductivity and thermal diffusivity decreased to 0.174 W/(m·K) and 0.220 mm²/s, respectively, indicating improved thermal insulation properties. This research provides a novel approach for the high-value utilization of cotton stalks and residual films, offering a potential solution to reduce agricultural waste pollution in Xinjiang and contributing to the development of low-cost and high-performance WPCs with wide-ranging applications. Full article

In this study, a flame-retardant wood-polymer composite was produced using huntite-hydromagnesite mineral, recognized for its non- flammability properties. In this context, wood-polymer composites were produced with the co-rotating twin-screw extrusion technique, while polypropylene was applied as the composite matrix, medium density fiberboard waste and inorganic huntite-hydromagnesite mineral were used as the reinforcement material. The proportion of wood powder additives was changed to 10% and 20%, and the huntite and hydromagnesite ratio was changed to 30%, 40%, 50% and 60%. Maleic anhydride grafted polypropylene, i.e., MAPP, was applied as a binder at a rate of 3%. Polypropylene, wood fibers, mineral powders, and MAPP blended in the mixer were processed in the extruder and turned into granules. Structural, morphological, thermal, mechanical, and flame-retardant properties of the composites were analyzed using XRD, SEM, FTIR, TGA, tensile testing, and the UL-94 vertical flammability test. Test samples were prepared to evaluate the physical and mechanical properties with a compression molding machine. It was concluded that the composites gained significant flame retardancy with the addition of huntite hydromagnesite. The potential for using this material in various fields and its compliance with the principles of circular economy and the Sustainable Development Goals (SDG 12) were noted. Full article

To date, two-dimensional metal–organic frameworks (2D MOFs) have attracted much attention in many fields. Owing to their ultra-high porosity and specific surface area, great structural diversity and functional tunability, as well as feasible precision design at the molecular level, 2D MOFs have won rapid development in the field of energy storage. However, as a coordination compound, MOFs possess poor structural stability and are prone to structural collapse in electrochemical reactions, which seriously limits their electrochemical performance. Therefore, there is an urgent need to improve the structural stability of MOF electrode materials. In this study, a 2D MOF@Ti₃C₂T_X hybrid was constructed, in which urea pyrimidinone isocyanate (UPy-NCO) units were introduced via a condensation reaction with the active functional groups on MOFs, thus forming multiple hydrogen bonds among MOF frameworks to strengthen their structural stability. Importantly, 2,6-diaminopyridine was utilized to modulate the structure and properties. Initially, the mono-coordination model of the N atom on a pyridine ring with metal ions could create defects and form further pores. Two −NH₂ groups helped to improve the grafting reaction degree of UPy-NCO, leading to an increased ratio of forming quadruple hydrogen bonds (H-bonds), further strengthening the structure of the hybrid. As expected, the Cu-MOF@Ti₃C₂T_X-20%DAP-UPy hybrid exhibited a specific capacitance of 148 F g⁻¹ at 1 A g⁻¹, which is 45% higher than that of Cu-MOF@Ti₃C₂T_X-UPy (102 F g⁻¹). A good capacitance retention of 88% was obtained as the current density increased from 0.2 to 5 A g⁻¹. Moreover, excellent cycling stability (91.1%) was obtained at 1 A g⁻¹ after 5000 cycles. Full article

Viroids are subviral plant pathogens composed of non-coding, small, circular, single-stranded RNAs that parasitize the transcriptional machinery of their host cells. For many years, viroid-induced diseases were mistakenly attributed to viruses due to similarities in symptoms and pathogenic behavior. However, advances in molecular biology over the past sixty years have clearly distinguished viroids from viruses and other pathogens in terms of genetic composition, structural features, and replication mechanisms. Citrus trees in the Mediterranean region appear to have been associated with viroid infections since ancient times. Nevertheless, the use of propagation material harboring asymptomatic viroid infections allowed for continued production of high-quality fruit. This delicate equilibrium was disrupted with the spread of novel citrus pathogens, prompting the adoption of new horticultural practices that emphasized the elimination of citrus pathogens—including viroids—from propagation material. Concurrently, a contrasting approach emerged in the late 1960s: the experimental use of “graft-transmissible dwarfing agents”—later identified as citrus viroids—to control citrus tree size. Our lab initiated work on citrus viroid-induced dwarfing in the early 1980s and continued this line of research for nearly two decades. Eventually, we concluded that it was impractical to simultaneously promote rigorous sanitation protocols while advocating for the use of viroids to induce dwarfing. This review summarizes key biological and molecular aspects of citrus and avocado viroids investigated in our laboratory, including the development of diagnostic techniques and the exploration of viroid-induced dwarfing as a horticultural tool. Full article

This study investigates the mechanical, thermal, and liquid resistance properties of injection-molded composites made from recycled polypropylene (rPP) reinforced with jute fillers. Maleic anhydride-grafted polypropylene (MAPP) was used as a compatibilizer to enhance filler–matrix interfacial bonding. Tensile, flexural, and Charpy impact tests, along with density measurements, heat deflection temperature (HDT) tests, and resistance to short-duration liquid contact, were conducted to evaluate the composites. Results indicate that the addition of jute powder significantly improved stiffness (Young’s modulus increased up to 233%) and thermal stability (HDT increased to 147 °C for rPP/J40/MAPP) while reducing impact toughness due to the brittle nature of jute fillers. MAPP-modified composites demonstrated enhanced tensile and flexural strength compared to unmodified counterparts, with tensile strength improving by approximately 23% for rPP/J30/MAPP. The composites exhibited excellent liquid resistance, showing no visible changes after exposure to various automotive and household fluids. Full article

Background: The socket preservation technique involves filling the bone defect created after tooth extraction with a bone substitute material. This helps to reduce bone resorption of the post-extraction alveolar ridge. Various types of bone substitute biomaterials are used as augmentation materials, including autogeneic, allogeneic, and xenogeneic materials. The purpose of this study was to evaluate changes in alveolar ridge dimensions and alterations of optical bone density in sockets grafted with two different biomaterials. Additionally, bone biopsies taken from the grafted sites underwent histological evaluation. Methods: This study enrolled 10 generally healthy patients, who were divided into two equal groups. Patients in the first group were treated with an allogeneic material (BIOBank^®, Biobank, Paris, France), while patients in the second group were treated with an xenogeneic material (Geistlich Bio-Oss^®, Geistlich Pharma AG, Wolhusen, Switzerland). Tooth extraction was performed, following which the appropriate material was placed into the debrided socket. The material was secured with a collagen membrane (Geistlich Bio-Gide^®, Geistlich Pharma AG, Wolhusen, Switzerland) and sutures, which were removed 7 to 10 days after the procedure. Micro-CBCT examinations were performed, for the evaluation of alveolar ridge dimensions and bone optical density, at 7–10 days and six months after the procedure. Bone trepanbiopsy was performed simultaneously to the implant placement, six months after socket preservation. The retrieved biopsy was subjected to histological examination via hematoxylin and eosin (H&E) staining and Masson’s trichrome staining. Results: The results showed that the allogeneic material was more effective in preserving alveolar buccal height and was probably more rapidly transformed into the patient’s own bone. Sockets grafted with the xenogeneic material presented higher optical bone density after six months. Both materials presented similar effectiveness in alveolar width preservation. Conclusions: Based on the outcomes of this study, it can be concluded that both materials are suitable for the socket preservation technique. However, the dimensional changes in the alveolar ridge and the quality of the newly formed bone may vary depending on the type of biomaterial used. Full article