Search Results (200)

The thermo-chemical treatment of dental implants leads to the formation of sodium titanate crystals on their surface. When in contact with blood, these crystals dissolve and trigger an ionic exchange cascade, resulting in the formation of a calcium apatite layer. This study, carried out both in vitro and in an animal model, aimed to determine whether the cooling rate of the treatment affects the size of the deposited crystals, and whether this in turn influences wettability and early bone-to-implant contact (BIC). A total of 50 dental implants and 50 titanium discs were treated using four different cooling rates, along with a control group. Crystal size was analyzed on implant surfaces using scanning electron microscopy, and wettability was assessed on titanium discs using a goniometer. Finally, the implants were placed in the tibiae of 13 rabbits, and histological analysis was performed after three weeks to compare BIC among groups. Results suggest that a cooling rate of 75 °C/h produces smaller sodium titanate crystals, which are associated with significantly improved surface wettability and a higher percentage of bone-to-implant contact after 3 weeks of healing (p < 0.05). Full article

The biologic response following the insertion of dental implants is a widely studied process. Recent research has highlighted the importance of implant surface topography and chemistry as highly influential factors in consolidating the dental implant with the surrounding biological environment. The hydrophilicity, or wettability, of dental implants plays a pivotal role in these interactions and successful osseointegration. A more well-established factor that can also influence the development of the tissue–implant interface is exposure to tobacco smoke. While the negative impact of smoking on the biological response of the tissue is clear, there has been no research evaluating the impact that tobacco smoke can have directly on the surface chemistry of dental implants. The present study aimed to explore the effect of smoking on implant surface chemistry and wettability in vitro. Five different implant disks (Ti-Mach, Ti-SLA, Ti-Alloy, Zirc-1 and Zirc-2) were subjected to contamination with tobacco smoke using a portable smoke infuser with dome enclosure. Occasional smoking (5×/day 10 min each for 3 days) and heavy smoking (20×/day for 10 min each for 10 days) were simulated. The wettability of the implant disks was evaluated via the contact angle technique using artificial blood and albumin, as well as saline as a control. It was determined that the contamination of implant surfaces due to smoking produces changes in the surface chemistry and wettability. Changes in the surface hydrophilicity differed based on the implant material. Within the constraints of this investigation, tobacco smoke improved the hydrophilicity of titanium surfaces but worsened that of ceramic surfaces when utilizing the testing solutions. Different implant surfaces exhibit different wetting behavior following contamination with nicotine smoke. This might have an impact on the treatment of peri-implantitis in smokers due to changes in implant surface hydrophilicity, which can affect the re-osseointegration process. Full article

Kidney disease causes the retention of uremic metabolites in blood, which is associated with many comorbidities. Hemodialysis does not properly clear many metabolites, including large, middle-sized, and small protein-bound uremic toxins (PBUTs). Adsorption strategies for metabolite removal require the development of engineered adsorbents with tailored surfaces to increase the binding of desired metabolites. Albumin is uniquely positioned for modifying blood-contacting surfaces to absorb uremic metabolites, as it (i) minimizes non-specific protein adsorption and (ii) binds a range of molecules at Sudlow Sites I and II with different affinities. It is unknown if albumin-modified surfaces retain the adsorption qualities of solution-free albumin, namely, adsorption stability or specificity. Herein, albumin was covalently attached to iron oxide nanoparticles and characterized using multiple methods. Metabolite adsorption was conducted by incubating particles in a model solution of thirty-three uremic metabolites associated with kidney failure. Adsorption efficiency, selectivity, and stability were affected by albumin concentration and incubation time. Metabolite adsorption was found to change with time, and it was more effective on albumin-modified particles than unmodified controls. The findings outlined in this paper are crucial for the design of next-generation advanced blood-contacting materials to enhance dialysis and blood purification for patients with kidney disease. Full article

Yersinia bacteria (Yersinia enterocolitica, Yersinia pseudotuberculosis) are commonly found in nature in all climatic zones and are isolated from food (mainly raw pork, unpasteurized milk, or contaminated water), soil, and surface water, rarely from contaminated blood. Yersinia infection occurs through sick or asymptomatic carriers and contact with the feces of infected animals. The invasion of specific bacterial serotypes into the host cell is based on the type 3 secretion system (T3SS), which directly introduces many effector proteins (Yersinia outer proteins—Yops) into the host cell. The course of yersiniosis can be acute or chronic, with the predominant symptoms of acute enteritis (rarely pseudo-appendicitis or septicemia develops). Clinical and laboratory diagnosis of yersiniosis is difficult. The infection requires confirmation by isolating Yersinia bacteria from feces or other biological materials, including lymph nodes, synovial fluid, urine, bile, or blood. The detection of antibodies in blood serum or synovial fluid is useful in the diagnostic process. The treatment of yersiniosis is mainly symptomatic. Uncomplicated infections (diarrhea and abdominal pain) usually do not require antibiotic therapy, which is indicated in severe cases. Surgical intervention is undertaken in the situations of intestinal necrosis. Given the diagnostic and therapeutic difficulties, this review discusses the prevalence of Y. enterocolitica and Y. pseudotuberculosis, their mechanisms of disease induction (virulence factors and host response), clinical manifestations, diagnostic and preventive methods, and treatment strategies in the context of current knowledge and available recommendations. Full article

Laparoscopic lens fogging and contamination pose significant challenges, leading to a reduced surgical field of view. Intraoperative cleaning to address these issues extends the surgical duration and elevates the risk of surgical site infections. The authors propose that a hydrophilic diamond-like carbon (DLC) coating would effectively mitigate fogging and fouling, thereby eliminating the requirement for intraoperative cleaning, while the scratch-resistant nature of DLC would provide additional benefits. The present study investigates the efficacy of aluminum oxide (Al₂O₃) as a dopant in diamond-like carbon (DLC) films for antifogging applications. The authors hypothesized that adding oxygen to the DLC matrix would increase surface energy by increased hydrogen bonding, resulting in a highly hydrophilic coating. Varying dopant concentrations were tested to observe their effects on hydrophilicity, transparency, biocompatibility, and wear properties. The doped films displayed a notable improvement in transparency throughout the visible spectrum. Plasma-cleaned samples demonstrated a substantial reduction in contact angles, achieving values less than 8°. The biocompatibility of these films was analyzed with CellTiter-Glo assays; the films demonstrated statistically similar levels of cell viability when compared to the control media. The absence of adenosine triphosphate released by blood platelets in contact with the DLC coatings suggests in vivo hemocompatibility. These films, characterized by high transparency, biocompatibility, and biostability, could be valuable for biomedical applications necessitating transparent coatings. Full article

The growing use of microfluidic-based devices necessitates an analysis of flow characteristics through both experimental methods and computational fluid dynamic (CFD) simulations. CFD simulations facilitate the investigation of various devices, including medical sensors, by providing detailed insights into flow behavior. In this study, we conducted experimental and CFD analysis of the microfluidic flow in three devices: a COVID-19 rapid test kit, a blood glucose kit, and a PDMS kit. Our findings revealed that the changes in wall adhesion (contact angles) during the capillary flow could cause significant deviation from theoretical flow speed predictions. A hemodynamic analysis of the blood glucose kit and PDMS kit showed that capillary filling decreased in length, and flow speed could depend on the microchannel diameter. CFD results indicated the prominent role of porosity in the simulation of porous media material such as the COVID-19 test kit, as well as surface tension coefficients and wall adhesion (contact angles) in blood glucose kits and PDMS kits. Therefore, considering adaptive dynamic contact angles in CFD simulation software such as Ansys-Fluent 2024 could result in a more accurate prediction than simplified theoretical techniques, which is useful for sensor optimization and development. Full article

Forensic and medical examiners are often required to sample the body of a victim (either living or deceased), or a suspect of a criminal offence, for foreign DNA. This can provide useful information when the alleged activity involves the presence of various bodily fluids such as blood, semen, and/or saliva, as well as skin contact made between a perpetrator and a victim. Optimal recovery techniques for the collection of DNA evidence, following crime-relevant skin contact, can be dependent on the surface being sampled. Additional factors to consider include the body areas typically contacted during various activities and the likelihood of non-self-DNA being present in those areas prior to contacts of interest. Therefore, an understanding of DNA transfer, prevalence, persistence, and recovery on a body can aid in the interpretation of DNA results given activity-level questions and increase the value of the findings from this type of evidence. This review aims to summarise research on DNA-TPPR concerning various human body surfaces following different types of activities. This review examines the prevalence of background DNA on different skin surfaces, the reported DNA transfer associated with different forms of contact, and how different cofounding factors can affect the persistence of DNA. Full article

Introduction: Healthcare-associated infections (HAIs) pose a significant global challenge, resulting in prolonged hospital stays, higher healthcare costs, and increased morbidity and mortality rates. Reusable medical equipment, such as tourniquets, represents a potential vector for infection transmission. Despite frequent use and close contact with patients’ skin, infection control protocols often overlook these devices. This study examines microbial contamination on the surface of reusable tourniquets in both emergency department and operating theatre settings. Methods: A cross-sectional study was conducted between March and September 2024 in Gdansk, Poland. Samples from tourniquets used in the emergency department and the operating theatre were collected after an indefinite period, 14 days, and 28 days. Bacterial contamination on the surfaces of the tourniquets was measured using Columbia agar blood medium and expressed as colony-forming units (CFUs) per cm². Results: Significant bacterial loads were detected on reusable tourniquets, with contamination levels varying by location and duration of use. The average number of CFU/cm² across all stages of this study was 545 CFU/cm² for the emergency department and 101 CFU/cm² for the operating theatre. Tourniquets used in the emergency department exhibited higher bacterial counts compared to those from the operating theatre, which showed a greater diversity of bacterial species. These findings underscore the need to revise infection control protocols for reusable tourniquets. Conclusion: This study provides critical data that may influence future policy changes aimed at reducing the risk of HAIs through the improved management of reusable medical devices. Full article

Hemodialysis (HD) is a critical treatment for patients with end-stage kidney disease (ESKD). The effectiveness of conventional dialyzers used there could be compromised during extended use due to limited blood compatibility of synthetic polymeric membranes and sub-optimal dialyzer design. In fact, blood flow in the hollow fiber (HF) membrane could trigger inflammatory responses and thrombus formation, leading to reduced filtration efficiency and limiting therapy duration, a consequence of flowing the patients’ blood through the lumen of each fiber while the dialysate passes along the inter-fiber space (IOF, inside-out filtration). This study investigates the development of HF membranes for “outside-in filtration” (OIF) in HD. In OIF, blood flows through the inter-fiber space while dialysate flows within the fiber lumens, reducing the risk of fiber clogging and potentially extending treatment duration. For the OIF mode, the membrane should have a blood-compatible outer selective layer in contact with the patient’s blood. We develop HFs for OIF via liquid-induced phase separation using PES/PVP (polyethersulphone/polyvinylpyrrolidone) blends. The fibers’ surface morphology (SEM, scanning electron microscopy), chemistry (ATR-FTIR—attenuated total reflection-Fourier transform infrared spectroscopy, XPS—X-ray photoelectron spectroscopy), transport properties, and uremic toxin removal from human plasma are evaluated and compared to commercial HFs. These membranes feature a smooth, hydrophilic outer layer, porous lumen, ultrafiltration coefficient of 13–34 mL m² h⁻¹ mmHg⁻¹, adequate mechanical properties, low albumin leakage, and toxin removal performance on par with commercial membranes in IOF and OIF. They offer potential for more efficient long-term HD by reducing clogging and systemic anticoagulation needs and enhancing treatment time and toxin clearance. Full article

Background/Objectives: Healthcare-associated infections (HAIs) and antimicrobial resistance (AMR) present significant challenges in modern healthcare, leading to increased morbidity, mortality, and healthcare costs. Examination gloves play a critical role in infection prevention by serving as a barrier to reduce the risk of cross-contamination between healthcare workers and patients. This manuscript aims to provide consensus-based guidelines for the optimal selection, use, and disposal of examination gloves in healthcare settings, addressing both infection prevention and environmental sustainability. Methods: The guidelines were developed using a multi-stage Delphi process involving healthcare experts from various disciplines. Recommendations were structured to ensure compliance with international regulations and sustainability frameworks aligned with the One Health approach and Sustainable Development Goals (SDGs). Results: Key recommendations emphasize selecting gloves based on clinical needs and compliance with EN 455 standards. Sterile gloves are recommended for surgical and invasive procedures, while non-sterile gloves are suitable for routine care involving contact with blood and other body fluids or contaminated surfaces. Proper practices include performing hand hygiene before and after glove use, avoiding glove reuse, and training healthcare providers on donning and removal techniques to minimize cross-contamination. Disposal protocols should follow local clinical waste management regulations, promoting sustainability through recyclable or biodegradable materials whenever feasible. Conclusions: These consensus-based guidelines aim to enhance infection control, improve the safety of patients and healthcare workers, and minimize environmental impact. By adhering to these evidence-based practices, grounded in European regulations, healthcare settings can establish safe and sustainable glove management systems that serve as a model for global practices. Full article

Artificial blood vessels made from polyurethane (PU) have been researched for many years but are not yet in clinical use. The main reason was that the PU materials are prone to degradation after contact with blood and will also cause inflammation after long-term implantation. At present, PU has made progress in biostability and biocompatibility, respectively. The PU for artificial blood vessels still requires a balance between material stability and biocompatibility to maintain its long-term stability in vivo, which needs to be further optimized. Based on the requirement of PU materials for artificial vascular applications, this paper views the development of biostable PU, bioactive PU, and bioresorbable PU. The improvement of biostable PU from the monomer structure, chemical composition, and additives are discussed to improve the long-term biostability in vivo. The surface grafting and functionalization methods of bioactive PU to reduce thrombosis and promote endothelialization for improving biocompatibility are summarized. In addition, the bioresorbable PU for tissue-engineered artificial blood vessels is discussed to balance between the degradation rate and mechanical properties. The ideal PU materials for artificial blood vessels must have good mechanical properties, stability, and biocompatibility at the same time. Finally, the application potential of PU materials in artificial vascular is prospected. Full article

This article compares the properties of the diamond-like carbon (DLC) coating with those of ZrN and (Zr,Hf)N coatings deposited on the Ti-6Al-4V titanium alloy substrate. To improve substrate adhesion during the deposition of the DLC coating, preliminary etching with chromium ions was conducted, ensuring the formation of a chromium-saturated diffusion surface layer in the substrate. A Si-DLC layer followed by a pure DLC layer was then deposited. The hardness of the coatings, their surface morphology, fracture strength in the scratch test, and tribological properties and wear resistance in the pin-on-disk test in contact with Al₂O₃ and steel indenters were investigated. The structure of the DLC coating was studied using transmission electron microscopy, and its corrosion resistance in an environment simulating blood plasma was also investigated. In the pin-on-disk test in contact with Al₂O₃ and AISI 52100 indenters, the DLC-coated sample demonstrates a much lower friction coefficient and significantly better wear resistance compared to the nitride-coated and uncoated samples. Both nitride coatings—(Zr,Hf)N and ZrN—and the DLC coating slow down the corrosive dissolution of the base compared to the uncoated sample. The corrosion currents of the (Zr,Hf)N-coated samples are 37.01 nA/cm², 20% higher than those of the ZrN-coated samples. The application of (Zr,Hf)N, ZrN, and DLC coatings on the Ti-6Al-4V alloy significantly inhibits dissolution currents (by 30–40%) and increases polarization resistance 1.5–2.0-fold compared to the uncoated alloy in 0.9% NaCl at 40 °C. Thus, the DLC coating of the described structure simultaneously provides effective wear and corrosion resistance in an environment simulating blood plasma. This coating can be considered in the manufacture of medical products (in particular, implants) from titanium alloys, including those functioning in the human body and subject to mechanical wear (e.g., knee joint endoprostheses). Full article

This study examines the hemocompatibility of gellan-gum-based hybrid hydrogels, with varying gellan-gum concentrations and constant sodium alginate and silk fibroin concentrations, respectively, in accordance with ISO 10993-4 standards. While previous studies have focused on cytocompatibility, the hemocompatibility of these hydrogels remains underexplored. Hydrogels were formulated with 0.3%, 0.5%, 0.75%, and 1% gellan gum combined with 3% silk fibroin and 4.2% sodium alginate separately, using physical and ionic cross-linking. Swelling behavior was analyzed in phosphate (pH 7.4) and acetic (pH 1.2) buffers and surface morphology was examined by scanning electron microscopy (SEM). Hemocompatibility tests included complete blood count (CBC), coagulation assays, hemolysis index, erythrocyte morphology, and platelet adhesion analysis. Results showed that gellan gum–sodium alginate hydrogels exhibited faster swelling than gellan gum–silk fibroin formulations. SEM indicated smoother surfaces with sodium alginate, while silk fibroin increased roughness, further amplified by higher gellan-gum concentrations. Hemocompatibility assays confirmed normal profiles in formulations with 0.3%, 0.5%, and 0.75% gellan gum, while 1% gellan gum caused significant hemolytic and thrombogenic activity. These findings highlight the excellent hemocompatibility of gellan-gum-based hydrogels, especially the sodium alginate variants, supporting their potential in bioengineering, tissue engineering, and blood-contacting biomedical applications. Full article

Polymer heart valves are a promising alternative to bioprostheses, the use of which is limited by the risks of calcific deterioration of devitalized preserved animal tissues. This is especially relevant in connection with the increasingly widespread use of transcatheter valves. Advances in modern organic chemistry provide a wide range of polymers that can replace biological material in the production of valve prostheses. In this work, the main properties of REPEREN^® polymer film, synthesized from methacrylic oligomers reinforced with ultra-thin (50 µm) polyamide fibers, are studied. The film structure was studied using scanning electron microscopy (SEM) and atomic force microscopy (AFM). The hydrophilicity and cytocompatibility with EA.hy926 endothelial cells were assessed, and a hemocompatibility evaluation was carried out by studying the platelet aggregation and adhesion upon contact of the REPEREN^® with blood. The mechanical behavior and biocompatibility (subcutaneous implantation in rats for up to 90 days, followed by a histological examination) were studied in comparison with a bovine pericardium (BP) cross-linked with an ethylene glycol diglycidyl ether (DE). The results showed that REPEREN^® films have two surfaces with a different relief, smooth and rough. The rough surface is more hydrophilic, hemo- and cytocompatible. Compared with the DE-BP, REPEREN^® has a higher ultimate tensile stress and better biocompatibility when implanted subcutaneously in rats. The key properties of REPEREN^® showed its potential for the development of a polymeric heart valve. Further studies should be devoted to assessing the durability of REPEREN^® valves and evaluating their function during orthotopic implantation in large animals. Full article

Modifying surface topography to prevent surface-induced thrombosis in cardiovascular implants allows endothelialization, which is the natural thrombo-resistance of blood-contacting surfaces, and is deemed to be the only long-term solution for hemocompatible materials. We adapted a simulation framework to predict platelet deposition on a modified surface and developed an optimization strategy to promote endothelial retention and limit platelet deposition. Under supraphysiological bulk shear stress, a maximum of 79% linear coverage was achieved. This study concludes that the addition of microtrenches promotes endothelial retention and can be improved through the optimal selection of geometric parameters. Full article