Effects of surface fluoride modification on TiO2 for the photocatalytic oxidation of toluene.

In the present study, we investigated the influence of surface fluorine (F) on TiO2 for the photocatalytic oxidation (PCO) of toluene. TiO2 modified with different F content was prepared and tested. It was found that with the increasing of F content, the toluene conversion rate first increased and then decreased. However, CO2 mineralization efficiency showed the opposite trend. Based on the characterizations, we revealed that F substitutes the surface hydroxyl of TiO2 to form the structure of Ti-F. The presence of the appropriate amount of surface Ti-F on TiO2 greatly enhanced the separation of photogenerated carriers, which facilitated the generation of ·OH and promoted the activity for the PCO of toluene. It was further revealed that the increase of only ·OH promoted the conversion of toluene to ring-containing intermediates, causing the accumulation of intermediates and then conversely inhibited the ·OH generation, which led to the decrease of the CO2 mineralization efficiency. The above results could provide guidance for the rational design of photocatalysts for toluene oxidation.

Biocompatible Janus microparticle synthesis in a microfluidic device.

Janus particles are popular in recent years due to their anisotropic physical and chemical properties. Even though there are several established synthesis methods for Janus particles, microfluidics-based methods are convenient and reliable due to low reagent consumption, monodispersity of the resultant particles and efficient control over reaction conditions. In this work a simple droplet-based microfluidic technique is utilized to synthesize magnetically anisotropic TiO2-Fe2O3 Janus microparticles. Two droplets containing reagents for Janus particle were merged by using an asymmetric device such that the resulting droplet contained the constituents within its two hemispheres distinct from each other. The synthesized Janus particles were observed under the optical microscope and the scanning electron microscope. Moreover, a detailed in vitro characterization of these particles was completed, and it was shown that these particles have a potential use for biomedical applications.

Study on the Antibacterial Activity and Bone Inductivity of Nanosilver/PLGA-Coated TI-CU Implants.

Background: Implants are widely used in the field of orthopedics and dental sciences. Titanium (TI) and its alloys have become the most widely used implant materials, but implant-associated infection remains a common and serious complication after implant surgery. In addition, titanium exhibits biological inertness, which prevents implants and bone tissue from binding strongly and may cause implants to loosen and fall out. Therefore, preventing implant infection and improving their bone induction ability are important goals. Purpose: To study the antibacterial activity and bone induction ability of titanium-copper alloy implants coated with nanosilver/poly (lactic-co-glycolic acid) (NSPTICU) and provide a new approach for inhibiting implant-associated infection and promoting bone integration. Methods: We first examined the in vitro osteogenic ability of NSPTICU implants by studying the proliferation and differentiation of MC3T3-E1 cells. Furthermore, the ability of NSPTICU implants to induce osteogenic activity in SD rats was studied by micro-computed tomography (micro-CT), hematoxylin-eosin (HE) staining, masson staining, immunohistochemistry and van gieson (VG) staining. The antibacterial activity of NSPTICU in vitro was studied with gram-positive Staphylococcus aureus (Sa) and gram-negative Escherichia coli (E. coli) bacteria. Sa was used as the test bacterium, and the antibacterial ability of NSPTICU implanted in rats was studied by gross view specimen collection, bacterial colony counting, HE staining and Giemsa staining. Results: Alizarin red staining, alkaline phosphatase (ALP) staining, quantitative real-time polymerase chain reaction (qRT-PCR) and western blot analysis showed that NSPTICU promoted the osteogenic differentiation of MC3T3-E1 cells. The in vitro antimicrobial results showed that the NSPTICU implants exhibited better antibacterial properties. Animal experiments showed that NSPTICU can inhibit inflammation and promote the repair of bone defects. Conclusion: NSPTICU has excellent antibacterial and bone induction ability, and has broad application prospects in the treatment of bone defects related to orthopedics and dental sciences.

Chronic exposure to TiO2 micro- and nano particles: A biochemical and histopathological experimental study.

The aim of this work was to analyze the effects of long-term exposure to titanium dioxide (TiO2) micro- (MPs) and nanoparticles (NPs) (six and 12 months) on the biochemical and histopathological response of target organs using a murine model. Male Wistar rats were intraperitoneally injected with a suspension of TiO2 NPs (5 nm; TiO2-NP5 group) or MPs (45 µm; TiO2-NP5 group); the control group was injected with saline solution. Six and 12 months post-injection, titanium (Ti) concentration in plasma and target organs was determined spectrometrically (ICP-MS). Blood smears and organ tissue samples were evaluated by light microscopy. Liver and kidney function was evaluated using serum biochemical parameters. Oxidative metabolism was assessed 6 months post-injection (determination of superoxide anion by nitroblue tetrazolium (NBT) test, superoxide dismutase (SOD) and catalase (CAT), lipid peroxidation, and paraoxonase 1). Titanium (Ti) concentration in target organs and plasma was significantly higher in the TiO2-exposed groups than in the control group. Histological evaluation showed the presence of titanium-based particles in the target organs, which displayed no structural alterations, and in blood monocytes. Oxidative metabolism analysis showed that TiO2 NPs were more reactive over time than MPs (p < .05) and mobilization of antioxidant enzymes and membrane damage varied among the studied organs. Clearance of TiO2 micro and nanoparticles differed among the target organs, and lung clearance was more rapid than clearance from the lungs and kidneys (p < .05). Conversely, Ti concentration in plasma increased with time (p < .05). In conclusion, neither serum biochemical parameters nor oxidative metabolism markers appear to be useful as biomarkers of tissue damage in response to TiO2 micro- and nanoparticle deposits at chronic time points.

Multi-objective optimization of custom implant abutment design for enhanced bone remodeling in single-crown implants using 3D finite element analysis.

The optimal configuration of a customized implant abutment is crucial for bone remodeling and is influenced by various design parameters. This study introduces an optimization process for designing two-piece zirconia dental implant abutments. The aim is to enhance bone remodeling, increase bone density in the peri-implant region, and reduce the risk of late implant failure. A 12-month bone remodeling algorithm subroutine in finite element analysis to optimize three parameters: implant placement depth, abutment taper degree, and gingival height of the titanium base abutment. The response surface analysis shows that implant placement depth and gingival height significantly impact bone density and uniformity. The taper degree has a smaller effect on bone remodeling. The optimization identified optimal values of 1.5 mm for depth, 35° for taper, and 0.5 mm for gingival height. The optimum model significantly increased cortical bone density from 1.2 to 1.937 g/cm3 in 2 months, while the original model reached 1.91 g/cm3 in 11 months. The standard deviation of density showed more uniform bone apposition, with the optimum model showing values 2 to 6 times lower than the original over 12 months. The cancellous bone showed a similar trend. In conclusion, the depth and taper have a significant effect on bone remodeling. This optimized model significantly improves bone density uniformity.

The Addition of Hydroxyapatite Nanoparticles on Implant Surfaces Modified by Zirconia Blasting and Acid Etching to Enhance Peri-Implant Bone Healing.

This study investigated the impact of adding hydroxyapatite nanoparticles to implant surfaces treated with zirconia blasting and acid etching (ZiHa), focusing on structural changes and bone healing parameters in low-density bone sites. The topographical characterization of titanium discs with a ZiHa surface and a commercially modified zirconia-blasted and acid-etched surface (Zi) was performed using scanning electron microscopy, profilometry, and surface-free energy. For the in vivo assessment, 22 female rats were ovariectomized and kept for 90 days, after which one implant from each group was randomly placed in each tibial metaphysis of the animals. Histological and immunohistochemical analyses were performed at 14 and 28 days postoperatively (decalcified lab processing), reverse torque testing was performed at 28 days, and histometry from calcified lab processing was performed at 60 days The group ZiHa promoted changes in surface morphology, forming evenly distributed pores. For bone healing, ZiHa showed a greater reverse torque, newly formed bone area, and bone/implant contact values compared to group Zi (p < 0.05; t-test). Qualitative histological and immunohistochemical analyses showed higher features of bone maturation for ZiHa on days 14 and 28. This preclinical study demonstrated that adding hydroxyapatite to zirconia-blasted and acid-etched surfaces enhanced peri-implant bone healing in ovariectomized rats. These findings support the potential for improving osseointegration of dental implants, especially in patients with compromised bone metabolism.

Influence of the Surface Topography of Titanium Dental Implants on the Behavior of Human Amniotic Stem Cells.

The dental implant surface plays a crucial role in osseointegration. The topography and physicochemical properties will affect the cellular functions. In this research, four distinct titanium surfaces have been studied: machined acting (MACH), acid etched (AE), grit blasting (GBLAST), and a combination of grit blasting and subsequent acid etching (GBLAST + AE). Human amniotic mesenchymal (hAMSCs) and epithelial stem cells (hAECs) isolated from the amniotic membrane have attractive stem-cell properties. They were cultured on titanium surfaces to analyze their impact on biological behavior. The surface roughness, microhardness, wettability, and surface energy were analyzed using interferometric microscopy, Vickers indentation, and drop-sessile techniques. The GBLAST and GBLAST + AE surfaces showed higher roughness, reduced hydrophilicity, and lower surface energy with significant differences. Increased microhardness values for GBLAST and GBLAST + AE implants were attributed to surface compression. Cell viability was higher for hAMSCs, particularly on GBLAST and GBLAST + AE surfaces. Alkaline phosphatase activity enhanced in hAMSCs cultured on GBLAST and GBLAST + AE surfaces, while hAECs showed no mineralization signals. Osteogenic gene expression was upregulated in hAMSCs on GBLAST surfaces. Moreover, α2 and ß1 integrin expression enhanced in hAMSCs, suggesting a surface-integrin interaction. Consequently, hAMSCs would tend toward osteoblastic differentiation on grit-blasted surfaces conducive to osseointegration, a phenomenon not observed in hAECs.

[Effect of zirconia personalized gingival penetration on peri-implant soft and hard tissue of thin gingival biotypes in the anterior region: a retrospective study].

Objective: To investigate the effect of zirconia personalized gingival structure on peri-implant soft and hard tissue stability after single-tooth implant restorations in patients with thin gingival biotypes in the anterior region, with a view to provide a clinical guideline. Methods: This retrospective study included 20 patients with thin gingival biotype and implant restorations in the anterior region. These patients included 9 males and 11 females, and the age was (35.2± 10.3) years. The patients were from the Department of Periodontal Implantology, Stomatology Hospital, Southern Medical University from January 2018 to December 2022. Computer-aided design/computer-aided manufacturing (CAD/CAM) techniques were used to fabricate a titanium base zirconia personalized gingival structure to maintain the soft-tissue perforated gingival contour of the anterior esthetic zone. This structure consists of two modalities: titanium base + zirconia outer crown or titanium base personalized zirconia abutment + zirconia outer crown. Clinical outcomes were recorded immediately and after delivery of the final restorations. Implant retention was recorded, esthetic scoring was performed using the pink esthetic index, the amount of bone resorption at the implant margins was measured based on digitized apical radiographs, and periodontal health was evaluated using the modified plaque index and the modified bleeding index. Results: The survival rate of the 20 implants was 100% after 3 years of wearing the final restorations, with a pink aesthetic score of 9.3±0.9. Bone resorption at the proximal and distal mesial margins of the implants was 0.09 (-0.21, 0.20) mm, 0.17 (-0.12, 0.27) mm after 3 years, respectively, and the difference was not statistically significant when compared to bone resorption immediately after placement of the final restoration [0(0, 0) mm] (Z=-1.03, P=0.394; Z=-2.05, P=0.065). Conclusions: Zirconia personalized gingival structure maintains the stability of peri-implant hard and soft tissues of thin gingival biotypes in the anterior region.

Effect of Nitrogen Doping on the Photocatalytic Properties and Antibiofilm Efficacy of Reduced TiO2 Nanoparticles.

Nanomaterial-mediated antibacterial photodynamic therapy (aPDT) emerges as a promising treatment against antibiotic-resistant bacterial biofilms. Specifically, titanium dioxide nanoparticles (TiO2 NPs) are being investigated as photosensitizers in aPDT to address biofilm related diseases. To enhance their photocatalytic performance in the visible spectral range for biomedical applications, various strategies have been adopted, including reduction of TiO2 NPs. However, despite improvements in visible-light photoactivity, reduced TiO2 NPs have yet to reach their expected performance primarily due to the instability of oxygen vacancies and their tendency to reoxidize easily. To address this, we present a two-step approach to fabricate highly visible-light active and stable TiO2 NP photocatalysts, involving nitrogen doping followed by a magnesium-assisted reductive annealing process. X-ray photoelectron spectroscopy analysis of the synthesized reduced nitrogen-doped TiO2 NPs (H:Mg-N-TiO2 NPs) reveals that the presence of nitrogen stabilizes oxygen vacancies and reduced Ti species, leading to increased production of reactive oxygen species under visible-light excitation. The improved aPDT efficiency translates to a 3-fold enhancement in the antibiofilm activity of nitrogen-doped compared to undoped reduced TiO2 NPs against both Gram-positive (Streptococcus mutans) and Gram-negative (Porphyromonas gingivalis, Fusobacterium nucleatum) oral pathogens. These results underscore the potential of H:Mg-N-TiO2 NPs in aPDT for combating bacterial biofilms effectively.

Nanofeatured surfaces in dental implants: contemporary insights and impending challenges.

Dental implant therapy, established as standard-of-care nearly three decades ago with the advent of microrough titanium surfaces, revolutionized clinical outcomes through enhanced osseointegration. However, despite this pivotal advancement, challenges persist, including prolonged healing times, restricted clinical indications, plateauing success rates, and a notable incidence of peri-implantitis. This review explores the biological merits and constraints of microrough surfaces and evaluates the current landscape of nanofeatured dental implant surfaces, aiming to illuminate strategies for addressing existing impediments in implant therapy. Currently available nanofeatured dental implants incorporated nano-structures onto their predecessor microrough surfaces. While nanofeature integration into microrough surfaces demonstrates potential for enhancing early-stage osseointegration, it falls short of surpassing its predecessors in terms of osseointegration capacity. This discrepancy may be attributed, in part, to the inherent "dichotomy kinetics" of osteoblasts, wherein increased surface roughness by nanofeatures enhances osteoblast differentiation but concomitantly impedes cell attachment and proliferation. We also showcase a controllable, hybrid micro-nano titanium model surface and contrast it with commercially-available nanofeatured surfaces. Unlike the commercial nanofeatured surfaces, the controllable micro-nano hybrid surface exhibits superior potential for enhancing both cell differentiation and proliferation. Hence, present nanofeatured dental implants represent an evolutionary step from conventional microrough implants, yet they presently lack transformative capacity to surmount existing limitations. Further research and development endeavors are imperative to devise optimized surfaces rooted in fundamental science, thereby propelling technological progress in the field.

Optimized Electrophoretic Deposition of Chitosan/Mesoporous Glass Nanoparticles with Gentamicin on Titanium Implants: Enhancing Hemocompatibility and Antibacterial Activity.

Titanium-based implants have long been studied and used for applications in bone tissue engineering, thanks to their outstanding mechanical properties and appropriate biocompatibility. However, many implants struggle with osseointegration and attachment and can be vulnerable to the development of infections. In this work, we have developed a composite coating via electrophoretic deposition, which is both bioactive and antibacterial. Mesoporous bioactive glass particles with gentamicin were electrophoretically deposited onto a titanium substrate. In order to validate the hypothesis that the quantity of particles in the coatings is sufficiently high and uniform in each deposition process, an easy-to-use image processing algorithm was designed to minimize human dependence and ensure reproducible results. The addition of loaded mesoporous particles did not affect the good adhesion of the coating to the substrate although roughness was clearly enhanced. After 7 days of immersion, the composite coatings were almost dissolved and released, but phosphate-related compounds started to nucleate at the surface. With a simple and low-cost technique like electrophoretic deposition, and optimized stir and suspension times, we were able to synthesize a hemocompatible coating that significantly improves the antibacterial activity when compared to the bare substrate for both Gram-positive and Gram-negative bacteria.

Roughness affects the response of human fibroblasts and macrophages to sandblasted abutments.

BACKGROUND: A strong seal of soft-tissue around dental implants is essential to block pathogens from entering the peri-implant interface and prevent infections. Therefore, the integration of soft-tissue poses a challenge in implant-prosthetic procedures, prompting a focus on the interface between peri-implant soft-tissues and the transmucosal component. The aim of this study was to analyse the effects of sandblasted roughness levels on in vitro soft-tissue healing around dental implant abutments. In parallel, proteomic techniques were applied to study the interaction of these surfaces with human serum proteins to evaluate their potential to promote soft-tissue regeneration. RESULTS: Grade-5 machined titanium discs (MC) underwent sandblasting with alumina particles of two sizes (4 and 8 µm), resulting in two different surface types: MC04 and MC08. Surface morphology and roughness were characterised employing scanning electron microscopy and optical profilometry. Cell adhesion and collagen synthesis, as well as immune responses, were assessed using human gingival fibroblasts (hGF) and macrophages (THP-1), respectively. The profiles of protein adsorption to the surfaces were characterised using proteomics; samples were incubated with human serum, and the adsorbed proteins analysed employing nLC-MS/MS. hGFs exposed to MC04 showed decreased cell area compared to MC, while no differences were found for MC08. hGF collagen synthesis increased after 7 days for MC08. THP-1 macrophages cultured on MC04 and MC08 showed a reduced TNF-α and increased IL-4 secretion. Thus, the sandblasted topography led a reduction in the immune/inflammatory response. One hundred seventy-six distinct proteins adsorbed on the surfaces were identified. Differentially adsorbed proteins were associated with immune response, blood coagulation, angiogenesis, fibrinolysis and tissue regeneration. CONCLUSIONS: Increased roughness through MC08 treatment resulted in increased collagen synthesis in hGF and resulted in a reduction in the surface immune response in human macrophages. These results correlate with the changes in protein adsorption on the surfaces observed through proteomics.

Wear and corrosion of titanium alloy spinal implants in vivo.

To investigate the wear and corrosion of titanium alloy spinal implants in vivo, we evaluated removed implants and their surrounding scar tissues from 27 patients between May 2019 and April 2021. We performed scanning electron microscopy, energy-dispersive X-ray spectroscopy, and histological analysis. The results revealed metal-like particles in the soft tissues of seven patients, without any considerable increase in inflammatory cell infiltration. Patients with fractures showed lower percentages of wear and corrosion compared with other patients (42% and 17% vs. 59% and 26%). Polyaxial screws exhibited higher wear and corrosion percentages (53% and 23%) compared with uniaxial screws (39% and 3%), although in patients with fracture, the reverse was observed (20% and 0% vs. 39% and 3%). We found that titanium alloy spinal implants experience some degree of wear and corrosion in vivo. The titanium alloy particles formed by wear exhibited good histocompatibility, not causing inflammation, foreign body reactions, or osteolysis. Therefore, spinal implants should be removed cautiously when treating titanium alloy spinal metallosis. The wear and corrosion of the implants increase with the increase in implantation time, although the screw structure does not significantly affect these changes.

Cutibacterium acnes biofilm formation is influenced by bone microenvironment, implant surfaces and bacterial internalization.

BACKGROUND: The bacterial persistence, responsible for therapeutic failures, can arise from the biofilm formation, which possesses a high tolerance to antibiotics. This threat often occurs when a bone and joint infection is diagnosed after a prosthesis implantation. Understanding the biofilm mechanism is pivotal to enhance prosthesis joint infection (PJI) treatment and prevention. However, little is known on the characteristics of Cutibacterium acnes biofilm formation, whereas this species is frequently involved in prosthesis infections. METHODS: In this study, we compared the biofilm formation of C. acnes PJI-related strains and non-PJI-related strains on plastic support and textured titanium alloy by (i) counting adherent and viable bacteria, (ii) confocal scanning electronic microscopy observations after biofilm matrix labeling and (iii) RT-qPCR experiments. RESULTS: We highlighted material- and strain-dependent modifications of C. acnes biofilm. Non-PJI-related strains formed aggregates on both types of support but with different matrix compositions. While the proportion of polysaccharides signal was higher on plastic, the proportions of polysaccharides and proteins signals were more similar on titanium. The changes in biofilm composition for PJI-related strains was less noticeable. For all tested strains, biofilm formation-related genes were more expressed in biofilm formed on plastic that one formed on titanium. Moreover, the impact of C. acnes internalization in osteoblasts prior to biofilm development was also investigated. After internalization, one of the non-PJI-related strains biofilm characteristics were affected: (i) a lower quantity of adhered bacteria (80.3-fold decrease), (ii) an increase of polysaccharides signal in biofilm and (iii) an activation of biofilm gene expressions on textured titanium disk. CONCLUSION: Taken together, these results evidenced the versatility of C. acnes biofilm, depending on the support used, the bone environment and the strain.

The regulatory effect of TiO2 nanotubes loaded with graphene oxide on macrophage polarization in an inflammatory environment.

BACKGROUND: Excessive inflammation is a major cause of implant failure. The surface morphology, hydrophilicity, and loading of biomaterials are major properties modulating anti-inflammatory macrophage activation. This paper investigates the regulatory effects of modifying the surface of Titanium dioxide nanotubes (TNTs) with graphene oxide (GO) on the polarization of mouse monocyte macrophages (RAW264.7). METHODS: TNT was produced by the anodic oxidation of titanium. GO was subsequently electrodeposited on the TNT to obtain a TNT-GO composite. The samples were characterised through scanning electron microscopy (SEM), Raman spectroscopy, and X-ray diffraction. RAW264.7 cells were separately seeded onto the surface of three groups of samples: pure Ti, TNT, and TNT-GO. Under the condition of lipopolysaccharide stimulation, the influence of the sample surfaces on the gene expression profiles was investigated through RNA sequence analysis. In addition, cell spreading was observed through SEM, cell adhesion and proliferation were analysed using the CCK8 assay, and the expression of inflammation-related factors was investigated by ELISA and cellular immunofluorescence staining. The production of reactive oxygen species (ROS) in the RAW264.7 cells on the surface of the three groups was detected via immunofluorescence staining. RESULTS: The CCK8 results indicated that the adhesion and proliferation of the RAW264.7 cells were reduced on the TNT and TNT-GO surfaces. ELISA results revealed significant differences in the pro-inflammatory factors tumour necrosis factor-α and interleukin-6 secretion among the three groups at 24 h (p < 0.05). The secretion of pro-inflammatory factors significantly reduced and the expression of anti-inflammatory factor IL-10 increased on the TNT and TNT-GO surfaces. The RNA sequencing, ELISA, and cell immunofluorescence staining test results suggested that the inflammatory response of M1 polarization was reduced and the M2 polarization of macrophages was induced on the TNT-GO surface, which may be attributed to the reduction in ROS production. CONCLUSIONS: Under lipopolysaccharide stimulation, the inflammatory response of the RAW264.7 cells was reduced and the M2 polarization of macrophages was promoted on the TNT-GO surface, which may be caused by the reduced ROS production. Consequently, the designed TNT-GO material is promising for implants owing to its excellent inflammation regulation ability.

Nano-Based Approaches in Surface Modifications of Dental Implants: A Literature Review.

Rehabilitation of fully or partially edentulous patients with dental implants represents one of the most frequently used surgical procedures. The work of Branemark, who observed that a piece of titanium embedded in rabbit bone became firmly attached and difficult to remove, introduced the concept of osseointegration and revolutionized modern dentistry. Since then, an ever-growing need for improved implant materials towards enhanced material-tissue integration has emerged. There is a strong belief that nanoscale materials will produce a superior generation of implants with high efficiency, low cost, and high volume. The aim of this review is to explore the contribution of nanomaterials in implantology. A variety of nanomaterials have been proposed as potential candidates for implant surface customization. They can have inherent antibacterial properties, provide enhanced conditions for osseointegration, or act as reservoirs for biomolecules and drugs. Titania nanotubes alone or in combination with biological agents or drugs are used for enhanced tissue integration in dental implants. Regarding immunomodulation and in order to avoid implant rejection, titania nanotubes, graphene, and biopolymers have successfully been utilized, sometimes loaded with anti-inflammatory agents and extracellular vesicles. Peri-implantitis prevention can be achieved through the inherent antibacterial properties of metal nanoparticles and chitosan or hybrid coatings bearing antibiotic substances. For improved corrosion resistance various materials have been explored. However, even though these modifications have shown promising results, future research is necessary to assess their clinical behavior in humans and proceed to widespread commercialization.

Experimental study on the biomechanical stability of complex acetabular fractures in the quadrilateral area: application of a dynamic anterior titanium-plate screw system.

BACKGROUND AND OBJECTIVE: Complex acetabular fractures involving quadrilateral areas are more challenging to treat during surgery. To date, there has been no ideal internal fixation for these acetabular fractures. The purpose of this study was to evaluate the biomechanical stability of complex acetabular fractures using a dynamic anterior titanium-plate screw system of the quadrilateral area (DAPSQ) by simulating the standing and sitting positions of pelvic specimens. MATERIALS AND METHODS: Eight formal in-preserved cadaveric pelvises aged 30-50 years were selected as the research objects. First, one hip of the normal pelvises was randomly used as the control model (group B) for measurement, and then one hip of the pelvises was randomly selected to make the fracture model in the 8 intact pelvises as the experimental model (group A) for measurement. In group A, acetabular both-column fractures in the quadrilateral area were established, and the fractures were fixed by DAPSQ. The biomechanical testing machine was used to load (simulated physiological load) from 400 N to 700 N at a 1 mm/min speed for 30 s in the vertical direction when the specimens were measured at random in simulated standing or sitting positions in groups. The horizontal displacement and longitudinal displacement of the acetabular fractures in the quadrilateral area were measured in both the standing and sitting simulations. RESULTS: As the load increased, no dislocation or internal fixation breakage occurred during the measurements. In the standing position, the horizontal displacement of the quadrilateral area fractures in group A and group B appeared to be less than 1 mm with loads ranging from 400 N to 700 N, and there was no significant difference between group A and group B (p > 0.05). The longitudinal displacement appeared to be greater than 1 mm with a load of 700 mm in group A (700 N, 2 cases), and the difference was significant between group A and group B (p < 0.05). In the sitting position, the horizontal and longitudinal displacements of the quadrilateral areas were within 0.5 mm in group A and group B, and there was no significant difference between group A and group B (p > 0.05). CONCLUSION: For complex acetabular fractures in the quadrilateral area, DAPSQ fixation may provide early sitting stability, but it is inappropriate for patients to stand too early.

Beyond microroughness: novel approaches to navigate osteoblast activity on implant surfaces.

Considering the biological activity of osteoblasts is crucial when devising new approaches to enhance the osseointegration of implant surfaces, as their behavior profoundly influences clinical outcomes. An established inverse correlation exists between osteoblast proliferation and their functional differentiation, which constrains the rapid generation of a significant amount of bone. Examining the surface morphology of implants reveals that roughened titanium surfaces facilitate rapid but thin bone formation, whereas smooth, machined surfaces promote greater volumes of bone formation albeit at a slower pace. Consequently, osteoblasts differentiate faster on roughened surfaces but at the expense of proliferation speed. Moreover, the attachment and initial spreading behavior of osteoblasts are notably compromised on microrough surfaces. This review delves into our current understanding and recent advances in nanonodular texturing, meso-scale texturing, and UV photofunctionalization as potential strategies to address the "biological dilemma" of osteoblast kinetics, aiming to improve the quality and quantity of osseointegration. We discuss how these topographical and physicochemical strategies effectively mitigate and even overcome the dichotomy of osteoblast behavior and the biological challenges posed by microrough surfaces. Indeed, surfaces modified with these strategies exhibit enhanced recruitment, attachment, spread, and proliferation of osteoblasts compared to smooth surfaces, while maintaining or amplifying the inherent advantage of cell differentiation. These technology platforms suggest promising avenues for the development of future implants.

CuxO decorated Ti3C2Tx MXene composites for non-enzymatic glucose sensing with large linear ranges.

Ti3C2Tx MXene/CuxO composites were prepared by acid etching combined with electrochemical technique. The abundant active sites on the surface of MXene greatly increase the loading of CuxO nanoparticles, and the synergistic effect between the different components of the composite can accelerate the oxidation reaction of glucose. The results indicate that at the working potential of 0.55 V (vs. Ag/AgCl), the glucose sensor based on Ti3C2Tx MXene/CuxO composite presents large linear concentration ranges from 1 µM to 4.655 mM (sensitivity of 361 µA mM-1 cm-2) and from 5.155 mM to 16.155 mM (sensitivity of 133 µA mM-1 cm-2). The limit of detection is 0.065 µM. In addition, the sensor effectively avoids the oxidative interference of common interfering species such as ascorbic acid, dopamine and uric acid. The sensor has good reproducibility, stability and acceptable recoveries for the detection of glucose in human sweat sample (97.5-103.3%) with RSD values less than 4%. Based on these excellent properties it has great potential for the detection of glucose in real samples.

Foliar-applied melatonin and titanium nanoparticles modulate cadmium (Cd) toxicity through minimizing Cd accumulation and optimizing physiological and biochemical properties in sage (Salvia officinalis L.).

Notwithstanding the fact that melatonin (MT) and titanium nanoparticles (Ti NPs) alone have been widely used recently to modulate cadmium (Cd) stress in plants, there is a gap in the comparative impacts of these materials on lowering Cd toxicity in sage plants. The objective of this study was to determine how foliar application of MT and Ti NPs affected the growth, Cd accumulation, photosynthesis, water content, lipid peroxidation, and essential oil (EO) quality and quantity of sage plants in Cd-contaminated soils. A factorial experiment was conducted using MT at 100 and 200 µM and Ti NPs at 50 and 100 mg L-1 topically, together with Cd toxicity at 10 and 20 mg Cd kg-1 soil. The results showed that Cd toxicity decreased plant growth and enhanced lipid peroxidation. The Cd stress at 20 mg kg-1 soil resulted in increases in Cd root (693%), Cd shoot (429%), electrolyte leakage (EL, 29%), malondialdehyde (MDA, 72%), shoot weight (31%), root weight (27%), chlorophyll (Chl) a + b (26%), relative water content (RWC, 23%), and EO yield (30%). The application of MT and Ti NPs controlled drought stress by reducing MDA and EL, enhancing plant weight, Chl, RWC, and EO production, and minimizing Cd accumulation in plant tissues. The predominant compounds in the EO were α-thujone, 1,8-cineole, ß-thujone, camphor, and α-humulene. MT and Ti NPs caused α-thujone to rise, whereas Cd stress caused it to fall. Based on heat map analysis, MDA was the trait that was most sensitive to treatments. In summary, the research emphasizes the possibility of MT and Ti NPs, particularly MT at 200 µM, to mitigate Cd toxicity in sage plants and enhance their biochemical reactions.