Journal of Applied Biomaterials & Functional Materials最新文献

After anastomosis of sutures or pins, the restoration of intestinal barrier function can avoid several complications, such as tissue damage and inflammation. Our previous studies demonstrated the feasibility of biodegradable magnesium (Mg) pins as novel anastomosing implants to spontaneously absorb in the body, avoiding secondary removal surgery and long-term inflammation. However, the effect of Mg pins on the intestinal tight junction barrier is rarely investigated. In this study, we conducted high-purity Mg pins inserted in the intestine of rats and prepared Mg extracts cultured intestinal epithelial cell line to investigate the biological effect on the intestinal barrier associated with tight junction protein expression. We discovered that the concentration of released Mg ions over 1.7 mM was the critical threshold, above which mRNA expression of intestinal tight junction and cell apoptosis were affected considerably. Results of the immunohistochemical analysis revealed that Mg functions to stimulate ZO-1, caspase-3, occluding, and claudin-3 expressions. We offer new insight into the effectiveness of biodegradable Mg materials as the next generation of intestinal anastomosis pins, which effectively filters toxins as well as bacteria, and reduces inflammation.

Objective: To assess the effect of bleaching on surface roughness and gloss of different CAD/CAM ceramic materials.

Methods: The ceramic materials included IPS e.max CAD (lithium disilicate), VITA ENAMIC (polymer infiltrated ceramic), and Celtra Duo CAD (zirconia reinforced lithium silicate). Samples of each material were randomly divided into four groups (n = 10); a control group immersed in distilled water, the second and third groups were treated with 20% carbamide peroxide (20% CP) and 35% carbamide peroxide (35% CP) bleaching agents for 4 h/day and 60 min/day respectively for 7 days. The fourth group was treated with 40% hydrogen peroxide (40% HP) applied twice, each turn for 20 min. After treatment, the surface roughness (using 3D non-contact profilometry) and surface gloss were assessed followed by imaging with a scanning electron microscope. The data were analyzed using multiple linear regression and Kruskal-Wallis one-way ANOVA tests (α = 0.05).

Results: The surface roughness (p = 0.157) and gloss (p = 0.073) of IPS e.max CAD were not significantly affected by the different bleaching treatments. Similarly, no significant effect on surface roughness (p = 0.162) and gloss (p = 0.965) were shown for Celtra Duo CAD. On the other hand, VITA ENAMIC was significantly affected when treated with 20% CP and 35% CP showing increased roughness (p = 0.001) and gloss (p = 0.008).

Conclusions: Home bleaching treatments (20% CP and 35% CP) significantly affected the surface roughness and gloss of VITA ENAMIC while IPS e.max CAD and Celtra Duo CAD were not affected by the different bleaching treatments.

Titanium (Ti) implants are widely used in medicine. Meanwhile, surface modification of Ti can strengthen the osseointegration of implants. In this study, we modified Ti implant surfaces, which was coated with GO, HA, HA-2wt%GO and HA-5wt%GO via electrophoresis deposition, to investigate their mechanisms and biological activity. Uncoated Ti was used as the control. Further, we examined the biological behavior and osteogenic performance of mouse bone marrow mesenchymal stem cells (BMSCs) cultured on coatings in vitro. We found that the HA-GO nanocomposite coating improved the roughness and hydrophilicity of the Ti surface. Compared with the uncoated Ti or Ti modified by HA or GO alone, cell adhesion and diffusion were enhanced on HA-GO-modified Ti surfaces. In addition, the proliferation and osteogenic differentiation of BMSCs in vitro were significantly improved on HA-GO-modified surfaces, whereas osteogenesis-related gene expression and alkaline phosphatase activity were slightly enhanced. Furthermore, we noted that bone regeneration was improved in the HA-2wt%GO group in vivo. Thus, the HA-2wt%GO nanocomposite coating might have potential applications in the field of dental implants.

Purpose: Bleeding is a leading cause of mortality and morbidity in the trauma and surgery field, using effective hemostatic agents can help us reduce bleeding especially in parenchymal hemorrhage. Nowadays polyvinyl alcohol (PVA) is known as a safe candidate for wound dressing and maybe a hemostatic agent. PVA-based hydrogel is a popular biocompatible material in the biomedical field especially when it has high water absorption. In this study, we investigated the PVA hydrogel's mechanical and biological properties as well as its hemostatic potential in parenchymal bleeding.

Methods: PVA hydrogel had made by the freeze-thawing approach, we used PVA hydrogel in comparison to standard treatment to investigate hemostatic potency. Also, we performed MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) tests to survey PVA cellular toxicity. After an acute liver injury, two groups of 12 rats were treated with PVA hydrogel or standard treatment with sterile gauze. The results including the time and volume of bleeding, and the time and survival rate of the rats were measured and compared.

Results: We saw that PVA hydrogel was safe with no cellular toxicity in the MTT assay. Regarding efficacy, PVA hydrogel increased rats' survival after bleeding from 75% to 91.7%, and decreased bleeding time (p: 0.015), and bleeding volume (p: 0.03) compared to the control group.

Conclusion: Polyvinyl alcohol is safe. It has good biological properties with no cellular toxicity and has a significant hemostatic effect and can be regarded in control of parenchymal hemorrhage.

Bletilla striata polysaccharide (BSP) is effective for wound healing and has important applications in health care. A series of blend hydrogels was designed with BSP and konjac glucomannan (KGM) in this study to overcome the deficient mechanical performance caused by the excessive dissolution of BSP without affecting its physiological activity. The interplay between them, as well as the effects of KGM concentration on the physical properties and microstructures of hydrogels, were also explored. It was proved that the frame of the hydrogel was primarily formed by KGM. BSP was dispersed uniformly and linked to KGM through hydrogen bonding, which effectively improved the physical properties, such as increasing the water-holding capacity, improving the swelling degree, and enhancing the mechanical properties. Blend hydrogel BK2-2 (containing 1.0% BSP and 1.0% KGM, w/v) was found to be the optimal formulation based on the thermal stability and microstructure, which was used for further research. In vitro experiments revealed the L929 cell proliferative effects of the blend hydrogel, and no difference was found with BSP sponge extract after 72 h of exposure. In vivo animal studies indicated that the BK2-2 accelerated wound healing compared with the control group; however, no difference was found with dressings only made of BSP. These results demonstrated that KGM improved the physical properties of BSP-based material without negatively affecting its physiological properties. Also, the BSP/KGM blend hydrogel had good comprehensive properties and is expected to be used as a wound healing material in the future.

Background: Streptococcus mutans (S. mutans) participates in the dental caries process. Titanium dioxide (TiO₂) nanoparticles produce reactive oxygen species capable of disrupting bacterial DNA synthesis by creating pores in cell walls and membranes.

Objective: The objective of this study was to determine the effect of TiO₂ on the disruption of S. mutans biofilm.

Methods: This study was conducted in four phases involving a TiO₂-containing toothbrush and TiO₂ nanoparticles. Each phase was completed using 24 h established S. mutans biofilm growth. Phase one data was collected through a bacterial plating study, assessing biofilm viability. Biofilm mass was evaluated in phase two of the study by measuring S. mutans biofilm grown on microtiter plates following crystal violet staining. The third phase of the study involved a generalized oxygen radical assay to determine the relative amount of oxygen radicals released intracellularly. Phase four of the study included the measurement of insoluble glucan/extracellular polysaccharide (EPS) synthesis using a phenol-sulfuric acid assay.

Results: Both exposure time and time intervals had a significant effect on bacterial viability counts (p = 0.0323 and p = 0.0014, respectively). Bacterial counts after 6 min of exposure were significantly lower than after 2 min (p = 0.034), compared to the no treatment control (p = 0.0056). As exposure time increased, the amount of remaining biofilm mass was statistically lower than the no treatment control. Exposure time had a significant effect on oxygen radical production. Both the 30 and 100 nm TiO₂ nanoparticles had a significant effect on bacterial mass. The silver nanoparticles and the 30 and 100 nm TiO₂ nanoparticles significantly inhibited EPS production.

Conclusion: The TiO₂-containing toothbrush kills, disrupts, and produces oxygen radicals that disrupt established S. mutans biofilm. TiO₂ and silver nanoparticles inhibit EPS production and reduce biofilm mass. The addition of TiO₂ to dental products may be effective in reducing cariogenic dental biofilm.

Objectives: This study aimed to compare the effectiveness of an experimental root canal irrigant and 17% Ethylene-di-amine tetra acetic acid for removal of the smear layer in the coronal, middle and apical portions of the root canal.

Materials and methods: Ninety human single rooted maxillary and mandibular teeth were selected for this study. The teeth were randomly divided into two experimental groups and one control group as follows: Group A (Ethanolic extract of Sapindus Mukorossi), Group B (17% EDTA), and Group C (Distilled water). The root canals of all three groups were prepared with stainless steel K-files by means of the standard step-back technique and irrigated with 5.25% sodium hypo chloride. The teeth were decoronated, following the irrigation and divided longitudinally into two-halves and visualized using scanning electron microscope (SEM) for the amount of smear layer present utilizing the three-point score system. The observations were noted both before and after the treatment. Nonparametric tests were applied for the comparison and p-value ⩽ 0.05 was considered as statistically significant.

Results: It was evident from that smear layer was completely removed in coronal portion of 27 out of 30 teeth in-group A. For middle and apical areas of group A, 24 and 19 teeth showed complete smear layer removal. In-group B it was found that there were 24, 21, and 3 teeth at coronal, middle and apical, areas respectively where smear layer were completely absent. Intra group comparison showed a significant difference (p = 0.002) in smear layer removal was found for group A at coronal, middle and apical thirds. Similarly, a significant difference (p = 0.001) was also found for group B; however heavy smear layer was found among the three parts of the canal for group C.

Conclusions: Ethanolic extract of Sapindus Mukorossi have higher effectiveness in removing the smear layer from the root canal in comparison to 17% EDTA.

To observe the metabolic changes and antialcoholic effect of Puerarin-PLGA nanoparticles (PUE-NP) in mice. PUE-NP was prepared and characterized by particle size distribution and morphology. The mouse models with acute alcoholism were established to observe their behavioral changes after alcohol poisoning. The expressions of biologically active enzymes such as CRE, BUN, AST, ALT in serum and SOD and TLR4 in liver of mice in each group were detected, and the pathological changes in liver and kidney tissues were observed by HE staining. The PUE-NP metabolism in mice was determined by in vitro release assay and HPLC. PUE-NP nanoparticles had good morphology and structure, and the mouse models with alcohol poisoning were established successfully. Compared with alcohol group, puerarin and PUE-NP increased the disappearance latency time of righting reflex, and the recovery time of righting reflex was significantly shortened. Water maze results showed that Puerarin and PUE-NP had inhibitory effect on impaired memory. HPLC results showed that PUE-NP reached its peak in mice after 1 h, and the content percentage was twice that of puerarin preparation alone, and the distribution time of puerarin concentration in vivo was prolonged, indicating that PLGA nanoparticles had a loading and slow-release effect on puerarin and increased the bioavailability of puerarin in mice. In addition, compared with the alcohol group, Puerarin and PUE-NP improved serum ALT, AST, CRE, and BUN levels in mice, enhanced SOD activity in liver, and inhibited TLR4 expression. The effect was better in the PUE-NP group than in the Puerarin group. PUE-NP delayed the release and metabolism of Puerarin and had better effect in the treatment of the alcoholic liver and kidney injury.

A tissue preparation method will inevitably alter the tissue content. This study aims to evaluate how different common sample preparation methods will affect the tissue morphology, biomechanical properties, and chemical composition of samples. The study focuses on intervertebral disc (IVD) tissue; however, it can be applied to other soft tissues. Raman spectroscopy synchronized with nanoindentation instrumentation was employed to investigate the compositional changes of IVD, specifically, nucleus pulposus (NP) and annulus fibrosus (AF), together with their biomechanical properties of IVD. These properties were examined through the following histological specimen types: fresh cryosection (control), fixed cryosection, and paraffin-embedded. The IVD tissue could be located using an optical microscope under three different preparation methods. Paraffin-embedded samples showed the most explicit details where the lamellae structure of AF could be identified. In terms of biomechanical properties, there was no significant difference between the fresh and fixed cryosection (p > 0.05). In contrast, the fresh cryosection and paraffin-embedded samples showed a significant difference (p < 0.05). It was also found that the tissue preparations affected the chemical content of the tissues and structure of the tissue, which are expected to contribute to biomechanical properties changes. Fresh cryosection and fixed cryosection samples are more promising to work with for biomechanical assessment in histological tissues. The findings fill essential gaps in the literature by providing valuable insight into the characteristics of IVD at the microscale. This study can also become a reference for a better approach to assessing the mechanical properties and chemical content of soft tissues at the microscale.

Objective: To determine the combined antitumor effect of bismuth lipophilic nanoparticles (BisBAL NP) and cetylpyridinium chloride (CPC) on human lung tumor cells.

Material and methods: The human lung tumor cells A549 were exposed to 1-100 µM BisBAL NP or CPC, either separately or in a 1:1 combination. Cell viability was measured with the PrestoBlue assay, the LIVE/DEAD assay, and fluorescence microscopy. The integrity and morphology of cellular microtubules were analyzed by immunofluorescence.

Results: A 24-h exposure to 1 µM solutions reduced A549 growth with 21.5% for BisBAL NP, 70.5% for CPC, and 92.4% for the combination (p < 0.0001), while a 50 µM BisBAL NP/CPC mixture inhibited cell growth with 99% (p < 0.0001). BisBAL NP-curcumin conjugates were internalized within 30 min of exposure and could be traced within the nucleus of tumor cells within 2 h. BisBAL NP, but not CPC, interfered with microtubule organization, thus interrupting cell replication, similar to the action mechanism of docetaxel.

Conclusion: The growth inhibition of A549 human tumor cells by BisBAL NP and CPC was cumulative as of 1 µM. The BisBAL NP/CPC combination may constitute an innovative and cost-effective alternative for treating human lung cancer.