Photoactivated Formation of an Extravascular Dynamic Hydrogel as an Intelligent Blood Flow Regulator to Reprogram the Immunogenic Landscape.

Long-term tumor starvation may be a potential strategy to elevate the antitumor immune response by depriving nutrients. However, combining long-term starvation therapy with immunotherapy often yields limited efficacy due to the blockage of immune cell migration pathways. Herein, an intelligent blood flow regulator (BFR) is first established through photoactivated in situ formation of the extravascular dynamic hydrogel to compress blood vessels, which can induce long-term tumor starvation to elicit metabolic stress in tumor cells without affecting immune cell migration pathways. By leveraging methacrylate-modified nanophotosensitizers (HMMAN) and biodegradable gelatin methacrylate (GelMA), the developed extravascular hydrogel dynamically regulates blood flow via enzymatic degradation. Additionally, aPD-L1 loaded into HMMAN continuously blocks immune checkpoints. Systematic in vivo experiments demonstrate that the combination of immune checkpoint blockade (ICB) and BFR-induced metabolic stress (BIMS) significantly delays the progression of Lewis lung and breast cancers by reshaping the tumor immunogenic landscape and enhancing antitumor immune responses.

Dental biomaterials redefined: molecular docking and dynamics-driven dental resin composite optimization.

BACKGROUND: Dental resin-based composites are widely recognized for their aesthetic appeal and adhesive properties, which make them integral to modern restorative dentistry. Despite their advantages, adhesion and biomechanical performance challenges persist, necessitating innovative strategies for improvement. This study addressed the challenges associated with adhesion and biomechanical properties in dental resin-based composites by employing molecular docking and dynamics simulation. METHODS: Molecular docking assesses the binding energies and provides valuable insights into the interactions between monomers, fillers, and coupling agents. This investigation prioritizes SiO2 and TRIS, considering their consistent influence. Molecular dynamics simulations, executed with the Forcite module and COMPASS II force field, extend the analysis to the mechanical properties of dental composite complexes. The simulations encompassed energy minimization, controlled NVT and NPT ensemble simulations, and equilibration stages. Notably, the molecular dynamics simulations spanned a duration of 50 ns. RESULTS: SiO2 and TRIS consistently emerged as influential components, showcasing their versatility in promoting solid interactions. A correlation matrix underscores the significant roles of van der Waals and desolvation energies in determining the overall binding energy. Molecular dynamics simulations provide in-depth insights into the mechanical properties of dental composite complexes. HEMA-SiO2-TRIS excelled in stiffness, BisGMA-SiO2-TRIS prevailed in terms of flexural strength, and EBPADMA-SiO2-TRIS offered a balanced combination of mechanical properties. CONCLUSION: These findings provide valuable insights into optimizing dental composites tailored to diverse clinical requirements. While EBPADMA-SiO2-TRIS demonstrates distinct strengths, this study emphasizes the need for further research. Future investigations should validate the computational findings experimentally and assess the material's response to dynamic environmental factors.

Preparation and performance evaluation of a novel orthodontic adhesive incorporating composite dimethylaminohexadecyl methacrylate-Polycaprolactone fibers.

This study addressed enamel demineralization, a common complication in fixed orthodontic treatment, by evaluating a novel orthodontic adhesive with DMAHDM-PCL composite fibers. These fibers, produced through electrospinning, were incorporated into orthodontic adhesive to create experimental formulations at different concentrations and a control group. The study assessed antimicrobial properties, biosafety, and mechanical characteristics. New orthodontic adhesive exhibited significant bacteriostatic effects, reducing bacterial biofilm activity and concentrations. Incorporating 1% and 3% DMAHDM-PCL did not affect cytocompatibility. Animal tests confirmed no inflammatory irritation. Shear bond strength and adhesive residual index results indicated that antimicrobial fibers didn't impact bonding ability. In conclusion, orthodontic adhesives with 3% DMAHDM-PCL fibers are potential antimicrobial bonding materials, offering a comprehensive solution to enamel demineralization in orthodontic patients.

4-META/MMA-TBB resin containing nano hydroxyapatite induces the healing of periodontal tissue repair in perforations at the pulp chamber floor.

We aimed to evaluate the materials based on 4-methacryloxyethyl trimellitate anhydride/methyl methacrylate tri-n-butylborane (Super-bond [SB]) and nano hydroxyapatite (naHAp) for the repair of perforation at pulp chamber floor (PPF) in vitro and in vivo models. SB and naHAp were mixed in the mass ratio of 10% or 30% to produce naHAp/SB. Human periodontal ligament stem cells (HPDLSCs) were cultured on resin discs of SB or naHAp/SB to analyze the effects of naHAp/SB on cell adhesion, proliferation, and cementoblastic differentiation. A rat PPF model was treated with SB or naHAp/SB to examine the effects of naHAp/SB on the healing of defected cementum and periodontal ligament (PDL) at the site of PPF. HPDLSCs were spindle-shaped and adhered to all resin discs. Changing the resin from SB to naHAp/SB did not significantly alter cell proliferation. Both 10% and 30% naHAp/SB were more effective than SB in promoting cementoblastic differentiation of HPDLSCs. In the rat PPF model, 30% naHAp/SB was more effective than SB in promoting the formation Sharpey's fiber-like structures with expression of the PDL-related marker and cementum-like structures with expression of cementum-related markers. In conclusion, 30% naHAp/SB can be the new restorative material for PPF because it exhibited the abilities of adhering to dentin and healing of defected periodontal tissue.

Temperature-responsive salt-resistant poly(sulfobetaine methacrylate)-based emulsifiers for heavy oils.

The emulsions prepared with most currently reported emulsifiers are stable only at room temperature and are susceptible to demulsification at higher temperatures. This thermal instability prevents their use in high-temperature and high-salt environments encountered oilfield extraction. To address this issue, in this study, two temperature-responsive emulsifiers, PSBMA and CS-PSBMA, were synthesized. Both emulsifiers exhibited the ability to form stable emulsions within the temperature range of 60-80 °C and undergo demulsification at 20-40 °C. A comprehensive investigation was conducted to assess the impact of emulsifier concentration, water-to-oil ratio, and salt ion concentration on the stability of emulsions formed by these two emulsifiers. The results demonstrated their remarkable emulsification capabilities across diverse oil phases. Notably, the novel emulsifier CS-PSBMA, synthesized through the grafting chitosan (CS) onto PSBMA, not only exhibits superior emulsion stability and UCST temperature responsiveness but also significantly enhanced the salt resistance of the emulsion. Remarkably, the emulsion maintained its stability even in the presence of monovalent salt ions at concentrations up to 2 mol/L (equivalent to a mineralization level of 1.33 × 105 mg/L in water) and divalent salt ions at concentrations up to 3 mol/L (equivalent to a mineralization level of 2.7 × 105 mg/L in water). The emulsions stabilized by both emulsifiers are resilient to harsh reservoir conditions and effectively emulsify heavy oils, enabling high-temperature emulsification and low-temperature demulsification. These attributes indicate their promising potential for industrial applications, particularly in the field of enhanced oil recovery.

Bonding of Composite Cements Containing 10-MDP to Zirconia Ceramics Without Dedicated Ceramic Primer.

PURPOSE: To measure zirconia-to-zirconia microtensile bond strength (µTBS) using composite cements with and without primer. MATERIALS AND METHODS: Two Initial Zirconia UHT (GC) sticks (1.8x1.8x5.0 mm) were bonded using four cements with and without their respective manufacturer's primer/adhesive (G-CEM ONE [GOne] and G-Multi Primer, GC; Panavia V5 [Pv5]), and Panavia SA Cement Universal [PSAu], and Clearfil Ceramic Plus, Kuraray Noritake; RelyX Universal (RXu) and Scotchbond Universal Plus [SBUp], 3M Oral Care). Specimens were trimmed to an hour-glass shaped specimen whose isthmus is circular in cross-section. After 1-week water storage, the specimens were either tested immediately (1-week µTBS) or first subjected to 50,000 thermocycles (50kTC-aged µTBS). The fracture mode was categorized as either adhesive interfacial failure, cohesive failure in composite cement, or mixed failure, followed by SEM fracture analysis of selected specimens. Data were analyzed using linear mixed-effects statistics (α = 0.05; variables: composite cement, primer/adhesive application, aging). RESULTS: The statistical analysis revealed no significant differences with aging (p = 0.3662). No significant difference in µTBS with/without primer and aging was recorded for GOne and PSAu. A significantly higher µTBS was recorded for Pv5 and RXu when applied with their respective primer/adhesive. Comparing the four composite cements when they were applied in the manner that resulted in their best performance, a significant difference in 50kTC-aged µTBS was found for PSAu compared to Pv5 and RXu. A significant decrease in µTBS upon 50kTC aging was only recorded for RXu in combination with SBUp. CONCLUSION: Adequate bonding to zirconia requires the functional monomer 10-MDP either contained in the composite cement, in which case a separate 10-MDP primer is no longer needed, or in the separately applied primer/adhesive.

GelMA-based hydrogel biomaterial scaffold: A versatile platform for regenerative endodontics.

Endodontic therapy, while generally successful, is primarily limited to mature teeth, hence the pressing need to explore regenerative approaches. Gelatin methacryloyl (GelMA) hydrogels have emerged as pivotal biomaterials, promising a bright future for dental pulp regeneration. Despite advancements in tissue engineering and biomaterials, achieving true pulp tissue regeneration remains a formidable task. GelMA stands out for its injectability, rapid gelation, and excellent biocompatibility, serving as the cornerstone of scaffold materials. In the pursuit of dental pulp regeneration, GelMA holds significant potential, facilitating the delivery of stem cells, growth factors, and other vital substances crucial for tissue repair. Presently, in the field of dental pulp regeneration, researchers have been diligently utilizing GelMA hydrogels as engineering scaffolds to transport various effective substances to promote pulp regeneration. However, existing research is relatively scattered and lacks comprehensive reviews and summaries. Therefore, the primary objective of this article is to elucidate the application of GelMA hydrogels as regenerative scaffolds in this field, thereby providing clear direction for future researchers. Additionally, this article provides a comprehensive discussion on the synthesis, characterization, and application of GelMA hydrogels in root canal therapy regeneration. Furthermore, it offers new application strategies and profound insights into future challenges, such as optimizing GelMA formulations to mimic the complex microenvironment of pulp tissue and enhancing its integration with host tissues.

Comparison of the effect of propolis and Gluma desensitizer on the management of dentin hypersensitivity: A randomized controlled trial.

OBJECTIVE: To compare the effect of propolis and gluma desensitisers on the management of dentin hypersensitivity. METHODS: The single-blind, randomised controlled trial was conducted at the Department of Operative Dentistry, Dr Ishrat ul Ebad Khan Institute of Oral Health Sciences, Dow University of Health Sciences, Karachi, from October 2020 to September 2021, and comprised patients with dentin hypersensitivity who had pain scores of at least 2 on the visual analogue scale. The teeth were randomised into propolis group A and Gluma group B. Baseline pain scores were assessed using visual analogue scale and Schiff's sensitivity scores and compared with scores immediately after the intervention, and then after one week and one month of the intervention. Data was analysed using SPSS 23. RESULTS: Of the 22 patients, 12(54.5%) were females and 10(45.4%) were males. Of the 80 teeth, there were 40(50%) in each of the 2 groups. Significant reduction was observed in dentin hypersensitivity immediately after the application of the desensitising agents (p<0.05). However, after one month, Gluma was more effective than propolis (p<0.05). CONCLUSIONS: Both Gluma and propolis were found to be effective desensitising agents, but the effectiveness of propolis decreased over one month. Clinical Trial Number: Clinical Trials.gov: NCT04819867.

Injectable hydrogel with doxorubicin-loaded ZIF-8 nanoparticles for tumor postoperative treatments and wound repair.

The need for tumor postoperative treatments aimed at recurrence prevention and tissue regeneration have raised wide considerations in the context of the design and functionalization of implants. Herein, an injectable hydrogel system encapsulated with anti-tumor, anti-oxidant dual functional nanoparticles has been developed in order to prevent tumor relapse after surgery and promote wound repair. The utilization of biocompatible gelatin methacryloyl (GelMA) was geared towards localized therapeutic intervention. Zeolitic imidazolate framework-8@ceric oxide (ZIF-8@CeO2, ZC) nanoparticles (NPs) were purposefully devised for their proficiency as reactive oxygen species (ROS) scavengers. Furthermore, injectable GelMA hydrogels loaded with ZC NPs carrying doxorubicin (ZC-DOX@GEL) were tailored as multifunctional postoperative implants, ensuring the efficacious eradication of residual tumor cells and alleviation of oxidative stress. In vitro and in vivo experiments were conducted to substantiate the efficacy in cancer cell elimination and the prevention of tumor recurrence through the synergistic chemotherapy approach employed with ZC-DOX@GEL. The acceleration of tissue regeneration and in vitro ROS scavenging attributes of ZC@GEL were corroborated using rat models of wound healing. The results underscore the potential of the multifaceted hydrogels presented herein for their promising application in tumor postoperative treatments.

Functional extracellular vesicles from SHEDs combined with gelatin methacryloyl promote the odontogenic differentiation of DPSCs for pulp regeneration.

BACKGROUND: Pulp regeneration is a novel approach for the treatment of immature permanent teeth with pulp necrosis. This technique includes the combination of stem cells, scaffolds, and growth factors. Recently, stem cell-derived extracellular vesicles (EVs) have emerged as a new methodology for pulp regeneration. Emerging evidence has proven that preconditioning is an effective scheme to modify EVs for better therapeutic potency. Meanwhile, proper scaffolding is of great significance to protect EVs from rapid clearance and destruction. This investigation aims to fabricate an injectable hydrogel loaded with EVs from pre-differentiated stem cells from human exfoliated deciduous teeth (SHEDs) and examine their effects on pulp regeneration. RESULTS: We successfully employed the odontogenic induction medium (OM) of SHEDs to generate functional EV (OM-EV). The OM-EV at a concentration of 20 µg/mL was demonstrated to promote the proliferation and migration of dental pulp stem cells (DPSCs). The results revealed that OM-EV has a better potential to promote odontogenic differentiation of DPSCs than common EVs (CM-EV) in vitro through Alizarin red phalloidin, alkaline phosphatase staining, and assessment of the expression of odontogenic-related markers. High-throughput sequencing suggests that the superior effects of OM-EV may be attributed to activation of the AMPK/mTOR pathway. Simultaneously, we prepared a photocrosslinkable gelatin methacryloyl (GelMA) to construct an OM-EV-encapsulated hydrogel. The hydrogel exhibited sustained release of OM-EV and good biocompatibility for DPSCs. The released OM-EV from the hydrogel could be internalized by DPSCs, thereby enhancing their survival and migration. In tooth root slices that were subcutaneously transplanted in nude mice, the OM-EV-encapsulated hydrogel was found to facilitate dentinogenesis. After 8 weeks, there was more formation of mineralized tissue, as well as higher levels of dentin sialophosphoprotein (DSPP) and dentin matrix protein-1 (DMP-1). CONCLUSIONS: The effects of EV can be substantially enhanced by preconditioning of SHEDs. The functional EVs from SHEDs combined with GelMA are capable of effectively promoting dentinogenesis through upregulating the odontogenic differentiation of DPSCs, which provides a promising therapeutic approach for pulp regeneration.

Evaluation of the surface characteristics and antibacterial properties of Titanium dioxide nanotube and methacryloyloxyethylphosphorylcholine (MPC) coated orthodontic brackets-a comparative invitro study.

OBJECTIVES: White spot lesions are the most common iatrogenic effect observed during orthodontic treatment. This study aimed to compare the surface characteristics and antibacterial action of uncoated and coated orthodontic brackets. MATERIALS AND METHODS: Sixty commercially available stainless steel brackets were coated with TiO2 nanotubes and methacryloyloxyethylphosphorylcholine. The sample was divided into Group 1: uncoated orthodontic brackets, Group 2: Stainless steel brackets with TiO2 nanotubes coating, Group 3: Stainless steel brackets with methacryloyloxyethylphosphorylcholine coating, and Group 4: Stainless steel brackets with TiO2 nanotubes combined with methacryloyloxyethylphosphorylcholine coating. Surface characterization was assessed using atomic force microscopy and scanning electron microscopy. Streptococcus mutans was selected to test the antibacterial ability of the orthodontic brackets, total bacterial adhesion and bacterial viability were assessed. The brackets were subjected to scanning electron microscopy to detect the presence of biofilm. RESULTS: The surface roughness was the greatest in Group 1 and least in Group 2 followed by Group 4 and Group 3 coated brackets. The optical density values were highest in Group 1 and lowest in Group 4. Comparison of colony counts revealed high counts in Group 1 and low counts in Group 4. A positive correlation between surface roughness and colony counts was obtained, however, was not statistically significant. CONCLUSIONS: The coated orthodontic brackets exhibited less surface roughness than the uncoated orthodontic brackets. Group 4 coated orthodontic brackets showed the best antibacterial properties. CLINICAL RELEVANCE: Coated orthodontic brackets prevent adhesion of streptococcus mutans and reduces plaque accumulation around the brackets thereby preventing formation of white spot lesions during orthodontic treatment.

pH- and Matrix Metalloproteinase-Responsive Multifunctional Bilayer Microneedles Platform for Treatment of Tinea Pedis.

Persistent foot odor and itchiness are common symptoms of tinea pedis, significantly disrupting the daily life of those affected. The cuticular barrier at the site of the tinea pedis is thickened, which impedes the effective penetration of antifungal agents. Additionally, fungi can migrate from the skin surface to deeper tissues, posing challenges in the current clinical treatment for tinea pedis. To effectively treat tinea pedis, we developed a platform of bilayer gelatin methacrylate (GelMA) microneedles (MNs) loaded with salicylic acid (SA) and FK13-a1 (SA/FK13-a1@GelMA MNs). SA/FK13-a1@GelMA MNs exhibit pH- and matrix metalloproteinase (MMP)-responsive properties for efficient drug delivery. The MNs are designed to deliver salicylic acid (SA) deep into the stratum corneum, softening the cuticle and creating microchannels. This process enables the antibacterial peptide FK13-a1 to penetrate through the stratum corneum barrier, facilitating intradermal diffusion and exerting antifungal and anti-inflammatory effects. In severe cases of tinea pedis, heightened local pH levels and MMP activity further accelerate drug release. Our research demonstrates that SA/FK13-a1@GelMA MNs are highly effective against Trichophyton mentagrophytes, Trichophyton rubrum, and Candida albicans. They also reduced stratum corneum thickness, fungal burden, and inflammation in a guinea pig model of tinea pedis induced by T. mentagrophytes. Furthermore, it was discovered that SA/FK13-a1@GelMA MNs exhibit excellent biocompatibility. These findings suggest that SA/FK13-a1@GelMA MNs have significant potential for the clinical treatment of tinea pedis as well as other fungal skin disorders.

Self-adjuvanting polymeric nanovaccines enhance IFN production and cytotoxic T cell response.

Vaccines represent one of the most powerful and cost-effective innovations for controlling a wide range of infectious diseases caused by various viruses and bacteria. Unlike mRNA and DNA-based vaccines, subunit vaccines carry no risk of insertional mutagenesis and can be lyophilized for convenient transportation and long-term storage. However, existing adjuvants are often associated with toxic effect and reactogenicity, necessitating expanding the repertoire of adjuvants with better biocompatibility, for instance, designing self-adjuvating polymeric carriers. We herein report a novel subunit vaccine delivery platform constructed via in situ free radical polymerization of C7A (2-(Hexamethyleneimino) ethyl methacrylate) and acrylamide around the surface of individual protein antigens. Using ovalbumin (OVA) as a model antigen, we observed substantial increases in both diameter (∼70 nm) and surface potential (-1.18 mV) following encapsulation, referred to as n(OVA)C7A. C7A's ultra pH sensitivity with a transition pH around 6.9 allows for rapid protonation in acidic environments. This property facilitates crucial processes such as endosomal escape and major histocompatibility complex (MHC)-I-mediated antigen presentation, culminating in the substantial CD8+ T cell activation. Additionally, compared to OVA nanocapsules without the C7A components and native OVA without modifications, we observed heightened B cell activation within the germinal center, along with remarkable increases in serum antibody and cytokine production. It's important to note that mounting evidence suggests that adjuvant effects, particularly its targeted stimulation of type I interferons (IFNs), can contribute to advantageous adaptive immune responses. Beyond its exceptional potency, the nanovaccine also demonstrated robust formation of immune memory and exhibited a favorable biosafety profile. These findings collectively underscore the promising potential of our nanovaccine in the realm of immunotherapy and vaccine development.

Redox-Responsive "Catch and Release" Cryogels: A Versatile Platform for Capture and Release of Proteins and Cells.

Macroporous cryogels are attractive scaffolds for biomedical applications, such as biomolecular immobilization, diagnostic sensing, and tissue engineering. In this study, thiol-reactive redox-responsive cryogels with a porous structure are prepared using photopolymerization of a pyridyl disulfide poly(ethylene glycol) methacrylate (PDS-PEG-MA) monomer. Reactive cryogels are produced using PDS-PEG-MA and hydrophilic poly(ethylene glycol) methyl ether methacrylate (PEGMEMA) monomers, along with a PEG-based cross-linker and photoinitiator. Functionalization of cryogels using a fluorescent dye via the disulfide-thiol exchange reactions is demonstrated, followed by release under reducing conditions. For ligand-mediated protein immobilization, first, thiol-containing biotin or mannose is conjugated onto the cryogels. Subsequently, fluorescent dye-labeled proteins streptavidin and concanavalin A (ConA) are immobilized via ligand-mediated conjugation. Furthermore, we demonstrate that the mannose-decorated cryogel could capture ConA selectively from a mixture of lectins. The efficiency of protein immobilization could be easily tuned by changing the ratio of the thiol-sensitive moiety in the scaffold. Finally, an integrin-binding cell adhesive peptide is attached to cryogels to achieve successful attachment, and the on-demand detachment of integrin-receptor-rich fibroblast cells is demonstrated. Redox-responsive cryogels can serve as potential scaffolds for a variety of biomedical applications because of their facile synthesis and modification.

Comparison study of surface-initiated hydrogel coatings with distinct side-chains for improving biocompatibility of polymeric heart valves.

Polymeric heart valves (PHVs) present a promising alternative for treating valvular heart diseases with satisfactory hydrodynamics and durability against structural degeneration. However, the cascaded coagulation, inflammatory responses, and calcification in the dynamic blood environment pose significant challenges to the surface design of current PHVs. In this study, we employed a surface-initiated polymerization method to modify polystyrene-block-isobutylene-block-styrene (SIBS) by creating three hydrogel coatings: poly(2-methacryloyloxy ethyl phosphorylcholine) (pMPC), poly(2-acrylamido-2-methylpropanesulfonic acid) (pAMPS), and poly(2-hydroxyethyl methacrylate) (pHEMA). These hydrogel coatings dramatically promoted SIBS's hydrophilicity and blood compatibility at the initial state. Notably, the pMPC and pAMPS coatings maintained a considerable platelet resistance performance after 12 h of sonication and 10 000 cycles of stretching and bending. However, the sonication process induced visible damage to the pHEMA coating and attenuated the anti-coagulation property. Furthermore, the in vivo subcutaneous implantation studies demonstrated that the amphiphilic pMPC coating showed superior anti-inflammatory and anti-calcification properties. Considering the remarkable stability and optimal biocompatibility, the amphiphilic pMPC coating constructed by surface-initiated polymerization holds promising potential for modifying PHVs.

POSS and PEG Contained Copolymer for Antibioadhesive Rigid Contact Lenses Materials Application.

Myopia is a global public health issue. Rigid contact lenses (RCLs) are an effective way to correct or control myopia. However, bioadhesion issues remain one of the significant obstacles limiting its clinical application. Although enhancing hydrophilicity through various surface treatments can mitigate this problem, the duration of effectiveness is short-lived and the processing involved is complex and costly. Herein, an antiadhesive RCLs material was designed via 8-armed methacrylate-POSS (8MA-POSS), and poly(ethylene glycol) methacrylate (PEGMA) copolymerization with 3-[tris(trimethylsiloxy)silyl] propyl methacrylate (TRIS). The POSS and PEG segments incorporated P(TRIS-co-PEGMA-co-8MA-POSS) (PTPM) material was obtained and their optical transparency, refractive index, resolution, hardness, surface charge, thermal features, and wettability were tested and optimized. The antibioadhesion activities, including protein, lipid, and bacteria, were evaluated as well. In vitro and in vivo results indicated that the optimized antibioadhesive PTPM materials present good biocompatibility and biosafety. Thus, such POSS and PEG segments containing material were a potential antibioadhesive RCL material option.

Effect of Porosity on the Colonization of Digital Light-Processed 3D Hydrogel Constructs toward the Development of a Functional Intestinal Model.

With the rapid increase of the number of patients with gastrointestinal diseases in modern society, the need for the development of physiologically relevant in vitro intestinal models is key to improve the understanding of intestinal dysfunctions. This involves the development of a scaffold material exhibiting physiological stiffness and anatomical mimicry of the intestinal architecture. The current work focuses on evaluating the scaffold micromorphology of gelatin-methacryloyl-aminoethyl-methacrylate-based nonporous and porous intestinal 3D, intestine-like constructs, fabricated via digital light processing, on the cellular response. To this end, Caco-2 intestinal cells were utilized in combination with the constructs. Both porous and nonporous constructs promoted cell growth and differentiation toward enterocyte-like cells (VIL1, ALPI, SI, and OCLD expression showed via qPCR, ZO-1 via immunostaining). The porous constructs outperformed the nonporous ones regarding cell seeding efficiency and growth rate, confirmed by MTS assay, live/dead staining, and TEER measurements, due to the presence of surface roughness.

Mussel-Mimetic Hydrogel Coating with Anticoagulant and Antiinflammatory Properties on a Poly(lactic acid) Vascular Stent.

Biodegradable stents are the most promising alternatives for the treatment of cardiovascular disease nowadays, and the strategy of preparing functional coatings on the surface is highly anticipated for addressing adverse effects such as in-stent restenosis and stent thrombosis. Yet, inadequate mechanical stability and biomultifunctionality limit their clinical application. In this study, we developed a multicross-linking hydrogel on the polylactic acid substrates by dip coating that boasts impressive antithrombotic ability, antibacterial capability, mechanical stability, and self-healing ability. Gelatin methacryloyl, carboxymethyl chitosan, and oxidized sodium alginate construct a double-cross-linking hydrogel through the dynamic Schiff base chemical and in situ blue initiation reaction. Inspired by the adhesion mechanism employed by mussels, a triple-cross-linked hydrogel is formed with the addition of tannic acid to increase the adhesion and antibiofouling properties. The strength and hydrophilicity of hydrogel coating are regulated by changing the composition ratio and cross-linking degree. It has been demonstrated in tests in vitro that the hydrogel coating significantly reduces the adhesion of proteins, MC3T3-E1 cells, platelets, and bacteria by 85% and minimizes the formation of blood clots. The hydrogel coating also exhibits excellent antimicrobial in vitro and antiinflammatory properties in vivo, indicating its potential value in vascular intervention and other biomedical fields.

Raman silent region - based method for detection of pesticides with cyano group.

Based on the fact that not all chemical substances possess good Raman signals, this article focuses on the Raman silent region signals of pesticides with cyano group. Under the optimized conditions of methanol-water (1:1, v/v) as the solvent, irradiation at 302 nm light source for 20 min, and the use of 0.5 mol/L KI as the aggregating agent, Surface-enhanced Raman spectroscopy (SERS) method for azoxystrobin detection was developed by the Raman silent region signal of 2230 cm-1, and verified by detecting the spiked grapes with different concentrations of azoxystrobin. Other four pesticides with cyano group also could be identified at the peak of 2180 cm-1, 2205 cm-1, 2125 cm-1, and 2130 cm-1 for acetamiprid, phoxim, thiacloprid and cymoxanil, respectively. When azoxystrobin or acetamiprid was mixed respectively with chlorpyrifos without cyano group, their SERS signals in the Raman silent region of chlorpyrifos were not interfered, while mixed with cymoxanil in different ratios (1:4, 1:1 and 4:1), respectively, each two pesticides with cyano group could be distinguished by the changes in the Raman silent region. In further, four pesticides with or without cyano group were mixed together in 1:1:1:1 (acetamiprid, cymoxanil, azoxystrobin chlorpyrifos), and each pesticide still could be identified even at 0.5 mg/L. The results showed that the SERS method combined with UV irradiation may provide a new way to monitor the pesticides with C≡N performance in the Raman silent region without interference from the food matrix.

Bioinspired zwitterionic triblock copolymers designed for colloidal drug delivery: 2 - Biological evaluation.

In this work, poly(lactide) nanoparticles were equipped with a bioinspired coating layer based on poly[2-(methacryloyloxy)ethyl phosphorylcholine] and then evaluated when administered to the lungs and after intravenous injection. Compared to the plain counterparts, the chosen zwitterionic polymer shell prevented the coated colloidal formulation from aggregation and conditioned it for lower cytotoxicity, protein adsorption, complement activation and phagocytic cell uptake. Consequently, no interference with the biophysical function of the lung surfactant system could be detected accompanied by negligible protein and cell influx into the bronchoalveolar space after intratracheal administration. When injected into the central compartment, the coated formulation showed a prolonged circulation half-life and a delayed biodistribution to the liver. Taken together, colloidal drug delivery vehicles would clearly benefit from the investigated poly[2-(methacryloyloxy)ethyl phosphorylcholine]-based polymer coatings.