Bacterial infection of wounds is an escalating medical problem,issuing threats to both global public health and personal health.Photothermal antibacterial technology as a novel sterilization strategy has outstanding s...Bacterial infection of wounds is an escalating medical problem,issuing threats to both global public health and personal health.Photothermal antibacterial technology as a novel sterilization strategy has outstanding sterilization efficiency,high safety and low risk of emergence of drug-resistant bacteria.By combining inherent antibacterial activity and light-assisted antibacterial treatment,developing novel multifunctional dressings with synergistic high-efficiency antibacterial effects and also promoting wound healing possesses attractive advantages in the field of treating bacterial wound infections in clinical care.Herein,a multifunctional hydrogel formed by in situ photo-cross linking was designed and prepared by first grafting methacrylic anhydride as a photosensitizer onto chitosan,and then introducing oxidatively synthesized polydopamine(PDA).The physicochemical characterizations of the synthesized hydrogels demonstrated their tunability certainly associated with PDA concentration,including pore size,water swelling,rheological properties and in vitro degradability.In addition,the composite hydrogels exhibited good adhesion,anti-oxidation and photothermal properties due to the existence of PDA.Within 10min upon exposure to 808 nm near-infrared(NIR)light irradiation,this hydrogel system displayed outstanding antibacterial activity against Staphylococcus aureus with almost 100%killing efficiency,of which rapid efficient sterilization plays a significant role in wound healing.Moreover,the hydrogel is capable of cytocompatibility and has low toxicity to murine fibroblasts(L929 and NIH/3T3).In the full-thickness wound defect infection model in mice,the wound closure ratio,inflammatory response,fibroblasts,neovascularization and epithelialization were measured.Animal experiments also reveal that the hydrogel assisted with NIR laser irradiation can inhibit effectively infection at an early stage and accelerate the wound healing process.In summary,this novel multifunctional injectable hydrogel exhibits excellent swelling capacity,bio-adhesion,antioxidant property,photothermal activity,efficient antibacterial property and facilitates skin healing,which has great promising application as a medical dressing biomaterial in infected wound carefields.展开更多
Present study aims at synthesizing a thermosensitive hydrogel for controlled release of insulin. According to a modified method, hydroxybutyl chitosan （HBC） hydrogel possessed thermal sensitivity is prepared which c...Present study aims at synthesizing a thermosensitive hydrogel for controlled release of insulin. According to a modified method, hydroxybutyl chitosan （HBC） hydrogel possessed thermal sensitivity is prepared which can form hydrogel at over 25℃. The HBC hydrogel is non-cytotoxic to mice fibroblasts cells （L929）. Insulin is 100% entrapped in the hydrogel, 38% of which is released in vitro from the concentration of 5% hydrogel after 48 h, whereas by enzymolysis with lysozyme, 80% of the total insulin is released after 48h. This study suggests that HBC hydrogel could be utilized for controlled release of insulin in a non-invasive manner.展开更多
Background Capsular contracture has become the most common complication associated with breast implant.Transforming growth factor-beta （TGF-β） is well known for a prominent role in fibrotic diseases.Due to the crit...Background Capsular contracture has become the most common complication associated with breast implant.Transforming growth factor-beta （TGF-β） is well known for a prominent role in fibrotic diseases.Due to the critical role of TGF-β in pathogenesis of capsular formation,we utilized thermosensitive C/GP hydrogel to controlled release of TGF-β receptor kinase inhibitor （SD208） and investigated their effects on capsular contracture.Methods In vitro degradation and drug release of C/GP hydrogel were performed.Twenty-four rabbits underwent subpanniculus implantation with 30 ml smooth silicone implants and were randomly divided into four groups as fellows：Group 1 received saline solution;Group 2 received SD208;Group 3 received SD208-C/GP;Group 4 received C/GP.At 8 weeks,the samples of capsular tissues were analyzed by hematoxylin and eosin and immunohistological staining.The mRNA expression of collagen Ⅲ and TGF-β1 was detected by RT-PCR assay.Results C/GP hydrogel could be applied as an ideal drug delivery vehicle which supported the controlled release of SD208.SD208-C/GP treatment showed a significant reduction in capsule thickness with fewer vessels.The histological findings confirmed that the lower amounts of inflammatory cells and fibroblasts infiltrate in SD208-C/GP group.In contrast,typical capsules with more vessel predominance were developed in control group.We did not observe the same inhibitory effect of SD208 or C/GP treatment on capsular contracture.Moreover,SD208-C/GP therapy yielded an evident down-regulation of collagen Ⅲ and TGF-β1 mRNA expression.Conclusions This study demonstrated that controlled release of TGF-β receptor kinase inhibitor from thermosensitive C/GP hydrogel could significantly prevent capsule formation after mammary implants.展开更多
By using an easily available PEG derivative and biopolymer chitosan, a self-healing hydrogel has been facilely prepared through the dynamic Schiff base. This biocompatible self-healing hydrogel can be used for drug-de...By using an easily available PEG derivative and biopolymer chitosan, a self-healing hydrogel has been facilely prepared through the dynamic Schiff base. This biocompatible self-healing hydrogel can be used for drug-delivery, 3D cell culture and as a basic platform to develop some organic-inorganic biohybrids. This mini-review summarized recent research about that chitosan based self-healing hydrogel and related materials, and discussed some future bio-applications of that hydrogel展开更多
Three-dimensional printing technologies exhibit tremendous potential in the advancing fields of tissue engineering and regenerative medicine due to the precise spatial control over depositing the biomaterial.Despite t...Three-dimensional printing technologies exhibit tremendous potential in the advancing fields of tissue engineering and regenerative medicine due to the precise spatial control over depositing the biomaterial.Despite their widespread utilization and numerous advantages,the development of suitable novel biomaterials for extrusion-based 3D printing of scaffolds that support cell attachment,proliferation,and vascularization remains a challenge.Multi-material composite hydrogels present incredible potential in this field.Thus,in this work,a multi-material composite hydrogel with a promising formulation of chitosan/gelatin functionalized with egg white was developed,which provides good printability and shape fidelity.In addition,a series of comparative analyses of different crosslinking agents and processes based on tripolyphosphate(TPP),genipin(GP),and glutaraldehyde(GTA)were investigated and compared to select the ideal crosslinking strategy to enhance the physicochemical and biological properties of the fabricated scaffolds.All of the results indicate that the composite hydrogel and the resulting scaffolds utilizing TPP crosslinking have great potential in tissue engineering,especially for supporting neo-vessel growth into the scaffold and promoting angiogenesis within engineered tissues.展开更多
Biological lung volume reduction （BLVR） using lung sealant has received more attention recently as a new non-surgical approach to emphysema treatment. Many tissue sealants have been studied but only a few have been ...Biological lung volume reduction （BLVR） using lung sealant has received more attention recently as a new non-surgical approach to emphysema treatment. Many tissue sealants have been studied but only a few have been proposed for BLVR. In this work, we prepared in situ forming chitosan-based hydrogels （CSG） using covalent cross-linking of chitosan and genipin in the cooperation of ionic interaction between chitosan and sodium orthophosphate hydrate （Na3PO4.12H20） and characterized by Fourier transform infrared spectroscopy, scanning electron microscopy and rheological methods. CSG showed short gelation time （8 min）, high swelling ratio （〉100 %） and non-toxicity （3T3 mouse fibroblast cell viability 〉80 %） under physiological conditions. The application of lung sealant for BLVR was tested in a Chinese dog and evaluated by chest computed tomography. After 3 weeks of the installation of CSG in bronchopulmonary segment, the gel formation was detected at a localized region of bronchi and the local atelectasis occurred. Our findings indicate that this chitosan-based hydrogel is a promising new candidate for use as a lung sealant for BLVR.展开更多
Neurotrophic keratopathy is a persistent defect of the corneal epithelium,with or without stromal ulceration,due to corneal nerve deficiency caused by a variety of etiologies.The treatment options for neurotrophic ker...Neurotrophic keratopathy is a persistent defect of the corneal epithelium,with or without stromal ulceration,due to corneal nerve deficiency caused by a variety of etiologies.The treatment options for neurotrophic keratopathy are limited.In this study,an ophthalmic solution was constructed from a chitosan-based thermosensitive hydrogel with long-term release of murine nerve growth factor(CTH-mNGF).Its effectiveness was evaluated in corneal denervation(CD)mice and patients with neurotrophic keratopathy.In the preclinical setting,CTH-mNGF was assessed in a murine corneal denervation model.CTH-mNGF was transparent,thermosensitive,and ensured sustained release of mNGF for over 20 hours on the ocular surface,maintaining the local mNGF concentration around 1300 pg/mL in vivo.Corneal denervation mice treated with CTH-mNGF for 10 days showed a significant increase in corneal nerve area and total corneal nerve length compared with non-treated and CTH treated mice.A subsequent clinical trial of CTH-mNGF was conducted in patients with stage 2 or 3 neurotrophic keratopathy.Patients received topical CTH-mNGF twice daily for 8 weeks.Fluorescein sodium images,Schirmer’s test,intraocular pressure,Cochet-Bonnet corneal perception test,and best corrected visual acuity were evaluated.In total,six patients(total of seven eyes)diagnosed with neurotrophic keratopathy were enrolled.After 8 weeks of CTH-mNGF treatment,all participants showed a decreased area of corneal epithelial defect,as stained by fluorescence.Overall,six out of seven eyes had fluorescence staining scores<5.Moreover,best corrected visual acuity,intraocular pressure,Schirmer’s test and Cochet-Bonnet corneal perception test results showed no significant improvement.An increase in corneal nerve density was observed by in vivo confocal microscopy after 8 weeks of CTH-mNGF treatment in three out of seven eyes.This study demonstrates that CTH-mNGF is transparent,thermosensitive,and has sustained-release properties.Its effectiveness in healing corneal epithelial defects in all eyes with neurotrophic keratopathy suggests CTH-mNGF has promising application prospects in the treatment of neurotrophic keratopathy,being convenient and cost effective.展开更多
Microbial infections of bones,particularly after joint replacement surgery,are a common occurrence in clinical settings and often lead to osteomyelitis(OM).Unfortunately,current treatment approaches for OM are not sat...Microbial infections of bones,particularly after joint replacement surgery,are a common occurrence in clinical settings and often lead to osteomyelitis(OM).Unfortunately,current treatment approaches for OM are not satisfactory.To address this issue,this study focuses on the development and evaluation of an injectable magnesium oxide(MgO)nanoparticle(NP)-coordinated phosphocreatine-grafted chitosan hydrogel(CMPMg-VCM)loaded with varying amounts of vancomycin(VCM)for the treatment of OM.The results demonstrate that the loading of VCM does not affect the formation of the injectable hydrogel,and the MgO-incorporated hydrogel exhibits anti-swelling properties.The release of VCM from the hydrogel effectively kills S.aureus bacteria,with CMPMg-VCM(50)showing the highest antibacterial activity even after prolonged immersion in PBS solution for 12 days.Importantly,all the hydrogels are non-toxic to MC3T3-E1 cells and promote osteogenic differentiation through the early secretion of alkaline phosphatase and calcium nodule formation.Furthermore,in vivo experiments using a rat OM model reveal that the CMPMg-VCM hydrogel effectively kills and inhibits bacterial growth,while also protecting the infected bone from osteolysis.These beneficial properties are attributed to the burst release of VCM,which disrupts bacterial biofilm,as well as the release of Mg ions and hydroxyl by the degradation of MgO NPs,which inhibits bacterial growth and prevents osteolysis.Overall,the CMPMg-VCM hydrogel exhibits promising potential for the treatment of microbial bone infections.展开更多
This study presents a thorough investigation into the use of single and twin-tailed cationic and anionic surfactant-modified chitosan(SMCS)hydrogel beads as effective adsorbents for the elimination of hazardous polycy...This study presents a thorough investigation into the use of single and twin-tailed cationic and anionic surfactant-modified chitosan(SMCS)hydrogel beads as effective adsorbents for the elimination of hazardous polycyclic aromatic hydrocarbons(PAHs)from aqueous solutions.The Chitosan(CS)hydrogel beads were modified with single/twin-tailed anionic surfactants,sodium dodecyl sulfate(SDS)and sodium bis(2-ethylhexyl)sulfosuccinate(AOT),and cationic surfactants,dodecyltrimethylammonium bromide(DTAB)and didodecyldimethylammonium bromide(DDAB),to enhance their adsorption capacity of PAHs.The CS and SMCS beads were evaluated for their structural,mechanical,and adsorption properties using a range of techniques,including infrared spectroscopy(IR),energy-dispersive X-ray spectroscopy(EDX),rheometry,and field emission scanning electron microscopy(FESEM).Adsorption experiments of naphthalene(Nap),acenaphthene(Ace),and phenanthrene(Phe)on SMCS beads demonstrate that they have significantly higher adsorption capacities than CS beads,due to increase in hydrophobic interactions.Adsorption capacity followed the trend,Phen>Ace>Nap for all the beads revealing that twin-tailed SMCS bead possess much higher adsorption capacities(Qmax)compared to single-tailed SMCS beads.For twin tailed surfactants,the maximum adsorption capacities for Nap,Ace and Phe varied as CS-AOT(CS-DDAB):430.0(323.8)611.60(538.18)633.39(536.99)mg/g respectively,outperforming other reported hydrogel beads.The study highlights the simplicity,eco-friendliness,and enhanced performance of surfactant modification for developing high-efficiency adsorbents,paving the way for cost-effective solutions in water re-mediation.展开更多
By combining the merits of radiative cooling(RC)and evaporation cooling(EC),radiative coupled evaporative cooling(REC)has attracted considerable attention for sub-ambient cooling purposes.However,for outdoor devices,t...By combining the merits of radiative cooling(RC)and evaporation cooling(EC),radiative coupled evaporative cooling(REC)has attracted considerable attention for sub-ambient cooling purposes.However,for outdoor devices,the interior heating power would increase the working temperature and fire risk,which would suppress their above-ambient heat dissipation capabilities and passive water cycle properties.In this work,we introduced a REC design based on an all-in-one photonic hydrogel for above-ambient heat dissipation and flame retardancy.Unlike conventional design RC film for heat dissipation with limited cooling power and fire risk,REC hydrogel can greatly improve the heat dissipation performance in the daytime with a high workload,indicating a 12.0℃lower temperature than the RC film under the same conditions in the outdoor experiment.In the nighttime with a low workload,RC-assisted adsorption can improve atmospheric water harvesting to ensure EC in the daytime.In addition,our REC hydrogel significantly enhanced flame retardancy by absorbing heat without a corresponding temperature rise,thus mitigating fire risks.Thus,our design shows a promising solution for the thermal management of outdoor devices,delivering outstanding performance in both heat dissipation and flame retardancy.展开更多
Solar-driven interfacial desalination(SID)offers a sustainable route for freshwater production,yet its long-term performance is compromised by salt crystallization and microbial fouling under complex marine conditions...Solar-driven interfacial desalination(SID)offers a sustainable route for freshwater production,yet its long-term performance is compromised by salt crystallization and microbial fouling under complex marine conditions.Zwitterionic polymers offer promising nonfouling capabilities,but current zwitterionic hydrogel-based solar evaporators(HSEs)suffer from inadequate hydration and salt vulnerability.Inspired by the natural marine environmental adaptive characteristics of saltwater fish,we report a superhydrated zwitterionic poly(trimethylamine N-oxide,PTMAO)/polyacrylamide(PAAm)/polypyrrole(PPy)hydrogel(PTAP)with dedicated water channels for efficient,durable,and nonfouling SID.The directly linked N⁺and O⁻groups in PTMAO establish a robust hydration shell that facilitates rapid water transport while resisting salt and microbial adhesion.Integrated PAAm and PPy networks enhance mechanical strength and photothermal conversion.PTAP achieves a high evaporation rate of 2.35 kg m^(−2)h^(−1)under 1 kW m^(–2)in 10 wt%NaCl solution,maintaining stable operation over 100 h without salt accumulation.Furthermore,PTAP effectively resists various foulants including proteins,bacterial,and algal adhesion.Molecular dynamics simulations reveal that the exceptional hydration capacity supports its nonfouling properties.This work advances the development of nonfouling HSEs for sustainable solar desalination in real-world marine environments.展开更多
Octopuses,due to their flexible arms,marvelous adaptability,and powerful suckers,are able to effortlessly grasp and disengage various objects in the marine surrounding without causing devastation.However,manipulating ...Octopuses,due to their flexible arms,marvelous adaptability,and powerful suckers,are able to effortlessly grasp and disengage various objects in the marine surrounding without causing devastation.However,manipulating delicate objects such as soft and fragile foods underwater require gentle contact and stable adhesion,which poses a serious challenge to now available soft grippers.Inspired by the sucker infundibulum structure and flexible tentacles of octopus,herein we developed a hydraulically actuated hydrogel soft gripper with adaptive maneuverability by coupling multiple hydrogen bond-mediated supramolecular hydrogels and vat polymerization three-dimensional printing,in which hydrogel bionic sucker is composed of a tunable curvature membrane,a negative pressure cavity,and a pneumatic chamber.The design of the sucker structure with the alterable curvature membrane is conducive to realize the reliable and gentle switchable adhesion of the hydrogel soft gripper.As a proof-of-concept,the adaptive hydrogel soft gripper is capable of implement diversified underwater tasks,including gingerly grasping fragile foods like egg yolks and tofu,as well as underwater robots and vehicles that station-keeping and crawling based on switchable adhesion.This study therefore provides a transformative strategy for the design of novel soft grippers that will render promising utilities for underwater exploration soft robotics.展开更多
Bone regeneration for non-load-bearing defects remains a significant clinical challenge requiring advanced biomaterials and cellular strategies.Adiposederived mesenchymal stem cells(AD-MSCs)have garnered significant i...Bone regeneration for non-load-bearing defects remains a significant clinical challenge requiring advanced biomaterials and cellular strategies.Adiposederived mesenchymal stem cells(AD-MSCs)have garnered significant interest in bone tissue engineering(BTE)because of their abundant availability,minimally invasive harvesting procedures,and robust differentiation potential into osteogenic lineages.Unlike bone marrow-derived mesenchymal stem cells,AD-MSCs can be easily obtained in large quantities,making them appealing alternatives for therapeutic applications.This review explores hydrogels containing polymers,such as chitosan,collagen,gelatin,and hyaluronic acid,and their composites,tailored for BTE,and emphasizes the importance of these hydrogels as scaffolds for the delivery of AD-MSCs.Various hydrogel fabrication techniques and biocompatibility assessments are discussed,along with innovative modifications to enhance osteogenesis.This review also briefly outlines AD-MSC isolation methods and advanced embedding techniques for precise cell placement,such as direct encapsulation and three-dimensional bioprinting.We discuss the mechanisms of bone regeneration in the AD-MSC-laden hydrogels,including osteoinduction,vascularization,and extracellular matrix remodeling.We also review the preclinical and clinical applications of AD-MSC-hydrogel systems,emphasizing their success and limitations.In this review,we provide a comprehensive overview of AD-MSC-based hydrogel systems to guide the development of effective therapies for bone regeneration.展开更多
Peripheral nerve injury causes severe neuroinflammation and has become a global medical challenge.Previous research has demonstrated that porcine decellularized nerve matrix hydrogel exhibits excellent biological prop...Peripheral nerve injury causes severe neuroinflammation and has become a global medical challenge.Previous research has demonstrated that porcine decellularized nerve matrix hydrogel exhibits excellent biological properties and tissue specificity,highlighting its potential as a biomedical material for the repair of severe peripheral nerve injury;however,its role in modulating neuroinflammation post-peripheral nerve injury remains unknown.Here,we aimed to characterize the anti-inflammatory properties of porcine decellularized nerve matrix hydrogel and their underlying molecular mechanisms.Using peripheral nerve injury model rats treated with porcine decellularized nerve matrix hydrogel,we evaluated structural and functional recovery,macrophage phenotype alteration,specific cytokine expression,and changes in related signaling molecules in vivo.Similar parameters were evaluated in vitro using monocyte/macrophage cell lines stimulated with lipopolysaccharide and cultured on porcine decellularized nerve matrix hydrogel-coated plates in complete medium.These comprehensive analyses revealed that porcine decellularized nerve matrix hydrogel attenuated the activation of excessive inflammation at the early stage of peripheral nerve injury and increased the proportion of the M2 subtype in monocytes/macrophages.Additionally,porcine decellularized nerve matrix hydrogel negatively regulated the Toll-like receptor 4/myeloid differentiation factor 88/nuclear factor-κB axis both in vivo and in vitro.Our findings suggest that the efficacious anti-inflammatory properties of porcine decellularized nerve matrix hydrogel induce M2 macrophage polarization via suppression of the Toll-like receptor 4/myeloid differentiation factor 88/nuclear factor-κB pathway,providing new insights into the therapeutic mechanism of porcine decellularized nerve matrix hydrogel in peripheral nerve injury.展开更多
The major aim of stroke therapy is to stimulate brain repair and improve behavioral recovery after cerebral ischemia.One option is to stimulate endogenous neurogenesis in the subventricular zone and direct the newly f...The major aim of stroke therapy is to stimulate brain repair and improve behavioral recovery after cerebral ischemia.One option is to stimulate endogenous neurogenesis in the subventricular zone and direct the newly formed neurons to the damaged area.However,only a small percentage of these neurons survive,and many do not reach the damaged area,possibly because the corpus callosum impedes the migration of subventricular zone-derived stem cells into the lesioned cortex.A second major obstacle to stem cell therapy is the strong inflammatory reaction induced by cerebral ischemia,whereby the associated phagocytic activity of brain macrophages removes both therapeutic cells and/or cell-based drug carriers.To address these issues,neurogenesis was electrically stimulated in the subventricular zone,followed by isolation of proliferating cells,including newly formed neurons,which were subsequently mixed with a nutritional hydrogel.This mixture was then transferred to the stroke cavity of day 14 post-stroke mice.We found that the performance of the treated animals improved in behavioral tests,including novel object,open field,hole board,grooming,and“time-to-feel”adhesive tape tests.Furthermore,immunostaining revealed that the stem cell marker nestin,the neuroepithelial marker Mash1,and the immature neuronal marker doublecortin-positive cells survived in the transplanted area for 2 weeks,possibly due to reduced phagocytic activity and supportive angiogenesis.These results clearly indicate that the transplantation of committed subventricular zone stem cells combined with a protective nutritional gel directly into the infarct cavity after the peak of stroke-induced neuroinflammation represents a feasible approach to improve neurorestoration after cerebral ischemia.展开更多
[Objective] The aim was to investigate the hemostatic effects of chitosan-based fibre on liver. [Method] The liver hemorrhage model of rabbit was established. Hemostasis was performed with chitosam-based fiber in expe...[Objective] The aim was to investigate the hemostatic effects of chitosan-based fibre on liver. [Method] The liver hemorrhage model of rabbit was established. Hemostasis was performed with chitosam-based fiber in experimental group, surgicel in control group and no material in blank group. The hemostatic effects were evaluated by total blood loss (TBL) and hemostatic rate. [Result] Experimental group had no bleeding in observation period, with the hemostatic rate of 100% and the blood loss of only (0.443±0.30) g/kg, better than the control group and blank group (P<0.005). [Conclusion] Chitosan-based fiber has effective hemostasis in liver wound, which will provide reliable information for the clinical trials.展开更多
A chitosan （CS）-based low-pH-sensitive intelligent corrosion inhibitor was prepared by loading a pH-sensitive hydrogel with benzotriazole （BTA）; the pH-sensitive hydrogel was synthetized by crosslinking CS with gl...A chitosan （CS）-based low-pH-sensitive intelligent corrosion inhibitor was prepared by loading a pH-sensitive hydrogel with benzotriazole （BTA）; the pH-sensitive hydrogel was synthetized by crosslinking CS with glutaraldehyde （GTA）. Analysis by Fou- tier-transform inflared （FT-IR） spectroscopy showed that Schiff reactions occurred between amino and aldehyde groups. The swelling abil- ity of the hydrogel was investigated using a mass method, and it was observed to swell more in an acidic environment than in an alkaline en- vironment. The hydrogel＇s loading capacity of BTA was approximately 0.377 g·g ^-1, and its release speed was faster in an acidic environment than in an alkaline environment because of its swelling behavior. The corrosion inhibition ability of the intelligent inhibitor was tested by immersion and electrochemical methods. The results showed that after 4 h of immersion, the polarization resistance （Rp） value of copper with the intelligent inhibitor was approximately twice of that of copper with BTA, indicating that the intelligent inhibitor could effectively prevent copper from corroding.展开更多
A series of biodegradable amphoteric chitosan-based flocculants （3-chloro-2-hydroxypropyl trimethyl ammonium chloride （CTA） modified carboxymethyl chitosan, denoted as CMC-CTA） with different substitution degrees ...A series of biodegradable amphoteric chitosan-based flocculants （3-chloro-2-hydroxypropyl trimethyl ammonium chloride （CTA） modified carboxymethyl chitosan, denoted as CMC-CTA） with different substitution degrees of CTA were prepared successfully. The content of carboxymethyl groups in each CMC-CTA sample was kept almost constant. The solubility of the various flocculants showed that, higher cationic content of flocculants caused a better solubility. The flocculation experiments using kaolin suspension as synthetic water at the laboratory scale indicated that the substitution degree of CTA was one of the key factors for the flocculation properties. With the increase of cationic content, the flocculants were demonstrated better flocculation performance and lower dosage requirement. Flocculation kinetics model of particles collisions combining zeta potential and turbidity measurements was employed to investigate the effects of the cationic content of the flocculants on the flocculation properties from the viewpoint of flocculation mechanism in detail. Furthermore, flocculation performance using raw water from Zhenjiang part of Yangtze River at the pilot scale showed the similar effects to those at the laboratory scale.展开更多
Silver nanoparticles(Ag NPs)have attracted attention in the field of biomaterials due to their excellent antibacterial property.However,the reducing and stabilizing agents used for the chemical reduction of Ag NPs are...Silver nanoparticles(Ag NPs)have attracted attention in the field of biomaterials due to their excellent antibacterial property.However,the reducing and stabilizing agents used for the chemical reduction of Ag NPs are usually toxic and may cause water pollution.In this work,Ag NPs(31.2 nm in diameter)were prepared using the extract of straw,an agricultural waste,as the reducing and stabilizing agent.Experimental analysis revealed that the straw extract contained lignin,the structure of which possesses phenolic hydroxyl and methoxy groups that facilitate the reduction of silver salts into Ag NPs.The surfaces of Ag NPs were negatively charged due to the encapsulation of a thin layer of lignin molecules that prevented their aggregation.After the prepared Ag NPs were added to the precursor solution of acrylamide,free radical polymerization was triggered without the need for extra heating or light irradiation,resulting in the rapid formation of an Ag NP-polyacrylamide composite hydrogel.The inhibition zone test proved that the composite hydrogel possessed excellent antibacterial ability due to the presence of Ag NPs.The prepared hydrogel may have potential applications in the fabrication of biomedical materials,such as antibacterial dressings.展开更多
STAT3 plays a particularly important role in several cancer-related signal transduction pathways.Silencing STAT3 via RNA interference or small molecule inhibitors induces the apoptosis of tumor cells,thereby inhibitin...STAT3 plays a particularly important role in several cancer-related signal transduction pathways.Silencing STAT3 via RNA interference or small molecule inhibitors induces the apoptosis of tumor cells,thereby inhibiting the growth of the tumors.In this study,short-hairpin RNA sequences targeting the STAT3 genes were designed,synthesized,and then connected to pGPU6/GFP/Neo plasmids as the shRNA-expression vectors.The expression of STAT3-shRNA was analyzed by real-time PCR,western blotting,and cell apoptosis assay to study the growth and apoptosis of the cells.Then,the effect of STAT3 knockdown on the NCI-H1650 cells was studied in a tumor mouse model.The results revealed that,after an in vitro transfection,the proliferation of NCI-H1650 cells was inhibited,and the cells were induced to apoptosis.The mRNA and protein expression levels of STAT3 were downregulated in the STAT3-shRNA group.In vivo,the tumor mass and volume in the STAT3-shRNA group were significantly lower than in the other two groups.Both the in vivo and in vitro results demonstrated a long-period inhibiting effect on NSCLC,especially in vivo,when the tumor inhibition rate could reach 50%in the STAT3-shRNA group,which is an exciting outcome.Moreover,the study of the conjugation of STAT3-shRNA and chitosan-based vectors revealed that they could be combined steadily with good cytocompati-bility and transfection efficiency.These results together provide convincing evidence for the application of STAT3-shRNA used in the treatment of non-small lung cancer,which could be a promoting prospect for the development of gene therapy.展开更多
基金funded by the National Natural Science Foundation of China(Nos.U21A20417 and 31930067)1.3.5 project for disciplines of excellence,West China Hospital,Sichuan University(No.ZYGD18002).
文摘Bacterial infection of wounds is an escalating medical problem,issuing threats to both global public health and personal health.Photothermal antibacterial technology as a novel sterilization strategy has outstanding sterilization efficiency,high safety and low risk of emergence of drug-resistant bacteria.By combining inherent antibacterial activity and light-assisted antibacterial treatment,developing novel multifunctional dressings with synergistic high-efficiency antibacterial effects and also promoting wound healing possesses attractive advantages in the field of treating bacterial wound infections in clinical care.Herein,a multifunctional hydrogel formed by in situ photo-cross linking was designed and prepared by first grafting methacrylic anhydride as a photosensitizer onto chitosan,and then introducing oxidatively synthesized polydopamine(PDA).The physicochemical characterizations of the synthesized hydrogels demonstrated their tunability certainly associated with PDA concentration,including pore size,water swelling,rheological properties and in vitro degradability.In addition,the composite hydrogels exhibited good adhesion,anti-oxidation and photothermal properties due to the existence of PDA.Within 10min upon exposure to 808 nm near-infrared(NIR)light irradiation,this hydrogel system displayed outstanding antibacterial activity against Staphylococcus aureus with almost 100%killing efficiency,of which rapid efficient sterilization plays a significant role in wound healing.Moreover,the hydrogel is capable of cytocompatibility and has low toxicity to murine fibroblasts(L929 and NIH/3T3).In the full-thickness wound defect infection model in mice,the wound closure ratio,inflammatory response,fibroblasts,neovascularization and epithelialization were measured.Animal experiments also reveal that the hydrogel assisted with NIR laser irradiation can inhibit effectively infection at an early stage and accelerate the wound healing process.In summary,this novel multifunctional injectable hydrogel exhibits excellent swelling capacity,bio-adhesion,antioxidant property,photothermal activity,efficient antibacterial property and facilitates skin healing,which has great promising application as a medical dressing biomaterial in infected wound carefields.
基金Acknowledgements This work was supported by a grant from International S＆T Cooperation Program of China （Grant No. 2013DFG32880）, the National Natural Science Foundation of China （Grant No. 31000423）, and the Doctoral Fund of Ministry of Education of China （Grant No. 20120132110012）
文摘Present study aims at synthesizing a thermosensitive hydrogel for controlled release of insulin. According to a modified method, hydroxybutyl chitosan （HBC） hydrogel possessed thermal sensitivity is prepared which can form hydrogel at over 25℃. The HBC hydrogel is non-cytotoxic to mice fibroblasts cells （L929）. Insulin is 100% entrapped in the hydrogel, 38% of which is released in vitro from the concentration of 5% hydrogel after 48 h, whereas by enzymolysis with lysozyme, 80% of the total insulin is released after 48h. This study suggests that HBC hydrogel could be utilized for controlled release of insulin in a non-invasive manner.
基金This research was supported by grants from the Heilongjiang Provincial Health Department （No. 2006-063） and National Natural Science Foundation of China （No. 30325042）.
文摘Background Capsular contracture has become the most common complication associated with breast implant.Transforming growth factor-beta （TGF-β） is well known for a prominent role in fibrotic diseases.Due to the critical role of TGF-β in pathogenesis of capsular formation,we utilized thermosensitive C/GP hydrogel to controlled release of TGF-β receptor kinase inhibitor （SD208） and investigated their effects on capsular contracture.Methods In vitro degradation and drug release of C/GP hydrogel were performed.Twenty-four rabbits underwent subpanniculus implantation with 30 ml smooth silicone implants and were randomly divided into four groups as fellows：Group 1 received saline solution;Group 2 received SD208;Group 3 received SD208-C/GP;Group 4 received C/GP.At 8 weeks,the samples of capsular tissues were analyzed by hematoxylin and eosin and immunohistological staining.The mRNA expression of collagen Ⅲ and TGF-β1 was detected by RT-PCR assay.Results C/GP hydrogel could be applied as an ideal drug delivery vehicle which supported the controlled release of SD208.SD208-C/GP treatment showed a significant reduction in capsule thickness with fewer vessels.The histological findings confirmed that the lower amounts of inflammatory cells and fibroblasts infiltrate in SD208-C/GP group.In contrast,typical capsules with more vessel predominance were developed in control group.We did not observe the same inhibitory effect of SD208 or C/GP treatment on capsular contracture.Moreover,SD208-C/GP therapy yielded an evident down-regulation of collagen Ⅲ and TGF-β1 mRNA expression.Conclusions This study demonstrated that controlled release of TGF-β receptor kinase inhibitor from thermosensitive C/GP hydrogel could significantly prevent capsule formation after mammary implants.
基金supported by the National Natural Science Foundation of China (No. 21534006)
文摘By using an easily available PEG derivative and biopolymer chitosan, a self-healing hydrogel has been facilely prepared through the dynamic Schiff base. This biocompatible self-healing hydrogel can be used for drug-delivery, 3D cell culture and as a basic platform to develop some organic-inorganic biohybrids. This mini-review summarized recent research about that chitosan based self-healing hydrogel and related materials, and discussed some future bio-applications of that hydrogel
基金The authors acknowledge the funding support from the National Natural Science Foundation of China(Nos.52175474 and 51775324)the China Scholarship Council(No.202006890054).
文摘Three-dimensional printing technologies exhibit tremendous potential in the advancing fields of tissue engineering and regenerative medicine due to the precise spatial control over depositing the biomaterial.Despite their widespread utilization and numerous advantages,the development of suitable novel biomaterials for extrusion-based 3D printing of scaffolds that support cell attachment,proliferation,and vascularization remains a challenge.Multi-material composite hydrogels present incredible potential in this field.Thus,in this work,a multi-material composite hydrogel with a promising formulation of chitosan/gelatin functionalized with egg white was developed,which provides good printability and shape fidelity.In addition,a series of comparative analyses of different crosslinking agents and processes based on tripolyphosphate(TPP),genipin(GP),and glutaraldehyde(GTA)were investigated and compared to select the ideal crosslinking strategy to enhance the physicochemical and biological properties of the fabricated scaffolds.All of the results indicate that the composite hydrogel and the resulting scaffolds utilizing TPP crosslinking have great potential in tissue engineering,especially for supporting neo-vessel growth into the scaffold and promoting angiogenesis within engineered tissues.
基金supported by the University of Chinese Academy of Sciences(UCAS)and Royal Thai Government(Office of The Civil Service Commission,OCSC)Scholarship(27012552)
文摘Biological lung volume reduction （BLVR） using lung sealant has received more attention recently as a new non-surgical approach to emphysema treatment. Many tissue sealants have been studied but only a few have been proposed for BLVR. In this work, we prepared in situ forming chitosan-based hydrogels （CSG） using covalent cross-linking of chitosan and genipin in the cooperation of ionic interaction between chitosan and sodium orthophosphate hydrate （Na3PO4.12H20） and characterized by Fourier transform infrared spectroscopy, scanning electron microscopy and rheological methods. CSG showed short gelation time （8 min）, high swelling ratio （〉100 %） and non-toxicity （3T3 mouse fibroblast cell viability 〉80 %） under physiological conditions. The application of lung sealant for BLVR was tested in a Chinese dog and evaluated by chest computed tomography. After 3 weeks of the installation of CSG in bronchopulmonary segment, the gel formation was detected at a localized region of bronchi and the local atelectasis occurred. Our findings indicate that this chitosan-based hydrogel is a promising new candidate for use as a lung sealant for BLVR.
基金supported by PLA General Hospital Program,No.LB20201A010024(to LW).
文摘Neurotrophic keratopathy is a persistent defect of the corneal epithelium,with or without stromal ulceration,due to corneal nerve deficiency caused by a variety of etiologies.The treatment options for neurotrophic keratopathy are limited.In this study,an ophthalmic solution was constructed from a chitosan-based thermosensitive hydrogel with long-term release of murine nerve growth factor(CTH-mNGF).Its effectiveness was evaluated in corneal denervation(CD)mice and patients with neurotrophic keratopathy.In the preclinical setting,CTH-mNGF was assessed in a murine corneal denervation model.CTH-mNGF was transparent,thermosensitive,and ensured sustained release of mNGF for over 20 hours on the ocular surface,maintaining the local mNGF concentration around 1300 pg/mL in vivo.Corneal denervation mice treated with CTH-mNGF for 10 days showed a significant increase in corneal nerve area and total corneal nerve length compared with non-treated and CTH treated mice.A subsequent clinical trial of CTH-mNGF was conducted in patients with stage 2 or 3 neurotrophic keratopathy.Patients received topical CTH-mNGF twice daily for 8 weeks.Fluorescein sodium images,Schirmer’s test,intraocular pressure,Cochet-Bonnet corneal perception test,and best corrected visual acuity were evaluated.In total,six patients(total of seven eyes)diagnosed with neurotrophic keratopathy were enrolled.After 8 weeks of CTH-mNGF treatment,all participants showed a decreased area of corneal epithelial defect,as stained by fluorescence.Overall,six out of seven eyes had fluorescence staining scores<5.Moreover,best corrected visual acuity,intraocular pressure,Schirmer’s test and Cochet-Bonnet corneal perception test results showed no significant improvement.An increase in corneal nerve density was observed by in vivo confocal microscopy after 8 weeks of CTH-mNGF treatment in three out of seven eyes.This study demonstrates that CTH-mNGF is transparent,thermosensitive,and has sustained-release properties.Its effectiveness in healing corneal epithelial defects in all eyes with neurotrophic keratopathy suggests CTH-mNGF has promising application prospects in the treatment of neurotrophic keratopathy,being convenient and cost effective.
基金supported by the Natural Science Foundation of China(no.82202664)Shenzhen Key Laboratory of Orthopaedic Diseases and Biomaterials Research(no.ZDSYS20220606100602005)+2 种基金Guangdong Basic and Applied Basic Research Foundation(no.2023A1515012764,2021A1515220053,2022A1515220038)Sichuan Science and Technology Program(2023ZYD0115)Shenzhen Science and Technology Project(JCYJ20190809165805604,JCYJ20220818102815033,JCYJ20220531094214032),and Shenzhen High-level Hospital Construction Fund.
文摘Microbial infections of bones,particularly after joint replacement surgery,are a common occurrence in clinical settings and often lead to osteomyelitis(OM).Unfortunately,current treatment approaches for OM are not satisfactory.To address this issue,this study focuses on the development and evaluation of an injectable magnesium oxide(MgO)nanoparticle(NP)-coordinated phosphocreatine-grafted chitosan hydrogel(CMPMg-VCM)loaded with varying amounts of vancomycin(VCM)for the treatment of OM.The results demonstrate that the loading of VCM does not affect the formation of the injectable hydrogel,and the MgO-incorporated hydrogel exhibits anti-swelling properties.The release of VCM from the hydrogel effectively kills S.aureus bacteria,with CMPMg-VCM(50)showing the highest antibacterial activity even after prolonged immersion in PBS solution for 12 days.Importantly,all the hydrogels are non-toxic to MC3T3-E1 cells and promote osteogenic differentiation through the early secretion of alkaline phosphatase and calcium nodule formation.Furthermore,in vivo experiments using a rat OM model reveal that the CMPMg-VCM hydrogel effectively kills and inhibits bacterial growth,while also protecting the infected bone from osteolysis.These beneficial properties are attributed to the burst release of VCM,which disrupts bacterial biofilm,as well as the release of Mg ions and hydroxyl by the degradation of MgO NPs,which inhibits bacterial growth and prevents osteolysis.Overall,the CMPMg-VCM hydrogel exhibits promising potential for the treatment of microbial bone infections.
基金the Department of Science and Technology(DST),Govt.of India for providing funds under the FIST program and PURSE grant vide No.SR/PURSE/2020/31 to the department of Chemistry,University of Kashmir.
文摘This study presents a thorough investigation into the use of single and twin-tailed cationic and anionic surfactant-modified chitosan(SMCS)hydrogel beads as effective adsorbents for the elimination of hazardous polycyclic aromatic hydrocarbons(PAHs)from aqueous solutions.The Chitosan(CS)hydrogel beads were modified with single/twin-tailed anionic surfactants,sodium dodecyl sulfate(SDS)and sodium bis(2-ethylhexyl)sulfosuccinate(AOT),and cationic surfactants,dodecyltrimethylammonium bromide(DTAB)and didodecyldimethylammonium bromide(DDAB),to enhance their adsorption capacity of PAHs.The CS and SMCS beads were evaluated for their structural,mechanical,and adsorption properties using a range of techniques,including infrared spectroscopy(IR),energy-dispersive X-ray spectroscopy(EDX),rheometry,and field emission scanning electron microscopy(FESEM).Adsorption experiments of naphthalene(Nap),acenaphthene(Ace),and phenanthrene(Phe)on SMCS beads demonstrate that they have significantly higher adsorption capacities than CS beads,due to increase in hydrophobic interactions.Adsorption capacity followed the trend,Phen>Ace>Nap for all the beads revealing that twin-tailed SMCS bead possess much higher adsorption capacities(Qmax)compared to single-tailed SMCS beads.For twin tailed surfactants,the maximum adsorption capacities for Nap,Ace and Phe varied as CS-AOT(CS-DDAB):430.0(323.8)611.60(538.18)633.39(536.99)mg/g respectively,outperforming other reported hydrogel beads.The study highlights the simplicity,eco-friendliness,and enhanced performance of surfactant modification for developing high-efficiency adsorbents,paving the way for cost-effective solutions in water re-mediation.
基金financially supported by the Science and Technology Innovation Program of Hunan Province(2024RC3003)the Central South University Innovation-Driven Research Programme(2023CXQD012)the Initiative for Sustainable Energy for its financial support。
文摘By combining the merits of radiative cooling(RC)and evaporation cooling(EC),radiative coupled evaporative cooling(REC)has attracted considerable attention for sub-ambient cooling purposes.However,for outdoor devices,the interior heating power would increase the working temperature and fire risk,which would suppress their above-ambient heat dissipation capabilities and passive water cycle properties.In this work,we introduced a REC design based on an all-in-one photonic hydrogel for above-ambient heat dissipation and flame retardancy.Unlike conventional design RC film for heat dissipation with limited cooling power and fire risk,REC hydrogel can greatly improve the heat dissipation performance in the daytime with a high workload,indicating a 12.0℃lower temperature than the RC film under the same conditions in the outdoor experiment.In the nighttime with a low workload,RC-assisted adsorption can improve atmospheric water harvesting to ensure EC in the daytime.In addition,our REC hydrogel significantly enhanced flame retardancy by absorbing heat without a corresponding temperature rise,thus mitigating fire risks.Thus,our design shows a promising solution for the thermal management of outdoor devices,delivering outstanding performance in both heat dissipation and flame retardancy.
基金supported by National Natural Science Foundation of China(22209036,U23A20119)Hebei Provincial Natural Science Foundation,Excellent Youth Project(E2023202069)+1 种基金National Key R&D Program of China(2024YFF0506000,2024YFB4609100)Fundamental Research Foundation from Hebei University of Technology(424132016,282021485).
文摘Solar-driven interfacial desalination(SID)offers a sustainable route for freshwater production,yet its long-term performance is compromised by salt crystallization and microbial fouling under complex marine conditions.Zwitterionic polymers offer promising nonfouling capabilities,but current zwitterionic hydrogel-based solar evaporators(HSEs)suffer from inadequate hydration and salt vulnerability.Inspired by the natural marine environmental adaptive characteristics of saltwater fish,we report a superhydrated zwitterionic poly(trimethylamine N-oxide,PTMAO)/polyacrylamide(PAAm)/polypyrrole(PPy)hydrogel(PTAP)with dedicated water channels for efficient,durable,and nonfouling SID.The directly linked N⁺and O⁻groups in PTMAO establish a robust hydration shell that facilitates rapid water transport while resisting salt and microbial adhesion.Integrated PAAm and PPy networks enhance mechanical strength and photothermal conversion.PTAP achieves a high evaporation rate of 2.35 kg m^(−2)h^(−1)under 1 kW m^(–2)in 10 wt%NaCl solution,maintaining stable operation over 100 h without salt accumulation.Furthermore,PTAP effectively resists various foulants including proteins,bacterial,and algal adhesion.Molecular dynamics simulations reveal that the exceptional hydration capacity supports its nonfouling properties.This work advances the development of nonfouling HSEs for sustainable solar desalination in real-world marine environments.
基金the financial support from the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB0470303)the National Key Research and Development Program of China (2022YFB4600101)+5 种基金the National Natural Science Foundation of China (52175201)the Research Program of Science and Technology Department of Gansu Province (24JRRA059, 24JRRA044, and 24YFFA014)the Science Fund of Shandong Laboratory of Advanced Materials and Green Manufacturing at Yantai (AMGM2024F12)the Major Program (ZYFZFX-2) of the Lanzhou Institute of Chemical Physics, CASthe Special Research Assistant Project of the Chinese Academy of Sciencesthe Oasis Scholar of Shihezi University
文摘Octopuses,due to their flexible arms,marvelous adaptability,and powerful suckers,are able to effortlessly grasp and disengage various objects in the marine surrounding without causing devastation.However,manipulating delicate objects such as soft and fragile foods underwater require gentle contact and stable adhesion,which poses a serious challenge to now available soft grippers.Inspired by the sucker infundibulum structure and flexible tentacles of octopus,herein we developed a hydraulically actuated hydrogel soft gripper with adaptive maneuverability by coupling multiple hydrogen bond-mediated supramolecular hydrogels and vat polymerization three-dimensional printing,in which hydrogel bionic sucker is composed of a tunable curvature membrane,a negative pressure cavity,and a pneumatic chamber.The design of the sucker structure with the alterable curvature membrane is conducive to realize the reliable and gentle switchable adhesion of the hydrogel soft gripper.As a proof-of-concept,the adaptive hydrogel soft gripper is capable of implement diversified underwater tasks,including gingerly grasping fragile foods like egg yolks and tofu,as well as underwater robots and vehicles that station-keeping and crawling based on switchable adhesion.This study therefore provides a transformative strategy for the design of novel soft grippers that will render promising utilities for underwater exploration soft robotics.
文摘Bone regeneration for non-load-bearing defects remains a significant clinical challenge requiring advanced biomaterials and cellular strategies.Adiposederived mesenchymal stem cells(AD-MSCs)have garnered significant interest in bone tissue engineering(BTE)because of their abundant availability,minimally invasive harvesting procedures,and robust differentiation potential into osteogenic lineages.Unlike bone marrow-derived mesenchymal stem cells,AD-MSCs can be easily obtained in large quantities,making them appealing alternatives for therapeutic applications.This review explores hydrogels containing polymers,such as chitosan,collagen,gelatin,and hyaluronic acid,and their composites,tailored for BTE,and emphasizes the importance of these hydrogels as scaffolds for the delivery of AD-MSCs.Various hydrogel fabrication techniques and biocompatibility assessments are discussed,along with innovative modifications to enhance osteogenesis.This review also briefly outlines AD-MSC isolation methods and advanced embedding techniques for precise cell placement,such as direct encapsulation and three-dimensional bioprinting.We discuss the mechanisms of bone regeneration in the AD-MSC-laden hydrogels,including osteoinduction,vascularization,and extracellular matrix remodeling.We also review the preclinical and clinical applications of AD-MSC-hydrogel systems,emphasizing their success and limitations.In this review,we provide a comprehensive overview of AD-MSC-based hydrogel systems to guide the development of effective therapies for bone regeneration.
基金supported by the Shenzhen Hong Kong Joint Funding Project,No.SGDX20230116093645007(to LY)the Shenzhen Science and Technology Innovation Committee International Cooperation Project,No.GJHZ20200731095608025(to LY)+7 种基金Shenzhen Development and Reform Commission’s Intelligent Diagnosis,Treatment and Prevention of Adolescent Spinal Health Public Service Platform,No.S2002Q84500835(to LY)Shenzhen Medical Research Fund,No.B2303005(to LY)Team-based Medical Science Research Program,No.2024YZZ02(to LY)Zhejiang Provincial Natural Science Foundation of China,No.LWQ20H170001(to RL)Basic Research Project of Shenzhen Science and Technology from Shenzhen Science and Technology Innovation Commission,No.JCYJ20210324103010029(to BY)Shenzhen Second People’s Hospital Clinical Research Fund of Guangdong Province High-level Hospital Construction Project,Nos.2023yjlcyj029(to BY),2023yjlcyj021(to LL)Guangdong Basic and Applied Basic Research Foundation,No.2022A1515110679(to LL)China Postdoctoral Science Foundation,No.2022M722203(to GL).
文摘Peripheral nerve injury causes severe neuroinflammation and has become a global medical challenge.Previous research has demonstrated that porcine decellularized nerve matrix hydrogel exhibits excellent biological properties and tissue specificity,highlighting its potential as a biomedical material for the repair of severe peripheral nerve injury;however,its role in modulating neuroinflammation post-peripheral nerve injury remains unknown.Here,we aimed to characterize the anti-inflammatory properties of porcine decellularized nerve matrix hydrogel and their underlying molecular mechanisms.Using peripheral nerve injury model rats treated with porcine decellularized nerve matrix hydrogel,we evaluated structural and functional recovery,macrophage phenotype alteration,specific cytokine expression,and changes in related signaling molecules in vivo.Similar parameters were evaluated in vitro using monocyte/macrophage cell lines stimulated with lipopolysaccharide and cultured on porcine decellularized nerve matrix hydrogel-coated plates in complete medium.These comprehensive analyses revealed that porcine decellularized nerve matrix hydrogel attenuated the activation of excessive inflammation at the early stage of peripheral nerve injury and increased the proportion of the M2 subtype in monocytes/macrophages.Additionally,porcine decellularized nerve matrix hydrogel negatively regulated the Toll-like receptor 4/myeloid differentiation factor 88/nuclear factor-κB axis both in vivo and in vitro.Our findings suggest that the efficacious anti-inflammatory properties of porcine decellularized nerve matrix hydrogel induce M2 macrophage polarization via suppression of the Toll-like receptor 4/myeloid differentiation factor 88/nuclear factor-κB pathway,providing new insights into the therapeutic mechanism of porcine decellularized nerve matrix hydrogel in peripheral nerve injury.
基金supported by European Union Funding Programme,PNRR,No. 760058(to DMH)the UEFISCDI Project,No. PN-III-P4-IDPCE-2020-059(to APW)
文摘The major aim of stroke therapy is to stimulate brain repair and improve behavioral recovery after cerebral ischemia.One option is to stimulate endogenous neurogenesis in the subventricular zone and direct the newly formed neurons to the damaged area.However,only a small percentage of these neurons survive,and many do not reach the damaged area,possibly because the corpus callosum impedes the migration of subventricular zone-derived stem cells into the lesioned cortex.A second major obstacle to stem cell therapy is the strong inflammatory reaction induced by cerebral ischemia,whereby the associated phagocytic activity of brain macrophages removes both therapeutic cells and/or cell-based drug carriers.To address these issues,neurogenesis was electrically stimulated in the subventricular zone,followed by isolation of proliferating cells,including newly formed neurons,which were subsequently mixed with a nutritional hydrogel.This mixture was then transferred to the stroke cavity of day 14 post-stroke mice.We found that the performance of the treated animals improved in behavioral tests,including novel object,open field,hole board,grooming,and“time-to-feel”adhesive tape tests.Furthermore,immunostaining revealed that the stem cell marker nestin,the neuroepithelial marker Mash1,and the immature neuronal marker doublecortin-positive cells survived in the transplanted area for 2 weeks,possibly due to reduced phagocytic activity and supportive angiogenesis.These results clearly indicate that the transplantation of committed subventricular zone stem cells combined with a protective nutritional gel directly into the infarct cavity after the peak of stroke-induced neuroinflammation represents a feasible approach to improve neurorestoration after cerebral ischemia.
文摘[Objective] The aim was to investigate the hemostatic effects of chitosan-based fibre on liver. [Method] The liver hemorrhage model of rabbit was established. Hemostasis was performed with chitosam-based fiber in experimental group, surgicel in control group and no material in blank group. The hemostatic effects were evaluated by total blood loss (TBL) and hemostatic rate. [Result] Experimental group had no bleeding in observation period, with the hemostatic rate of 100% and the blood loss of only (0.443±0.30) g/kg, better than the control group and blank group (P<0.005). [Conclusion] Chitosan-based fiber has effective hemostasis in liver wound, which will provide reliable information for the clinical trials.
基金supported by the National Natural Science Foundation of China (No. 51222106)the Fundamental Research Funds for the Central Universities of China (No. FRF-TP-14-011C1)
文摘A chitosan （CS）-based low-pH-sensitive intelligent corrosion inhibitor was prepared by loading a pH-sensitive hydrogel with benzotriazole （BTA）; the pH-sensitive hydrogel was synthetized by crosslinking CS with glutaraldehyde （GTA）. Analysis by Fou- tier-transform inflared （FT-IR） spectroscopy showed that Schiff reactions occurred between amino and aldehyde groups. The swelling abil- ity of the hydrogel was investigated using a mass method, and it was observed to swell more in an acidic environment than in an alkaline en- vironment. The hydrogel＇s loading capacity of BTA was approximately 0.377 g·g ^-1, and its release speed was faster in an acidic environment than in an alkaline environment because of its swelling behavior. The corrosion inhibition ability of the intelligent inhibitor was tested by immersion and electrochemical methods. The results showed that after 4 h of immersion, the polarization resistance （Rp） value of copper with the intelligent inhibitor was approximately twice of that of copper with BTA, indicating that the intelligent inhibitor could effectively prevent copper from corroding.
基金supported by the Key Natural Science Foundation of China (No. 51073077,50938004,50825802)the Research Project of Ministry of Housing and Urban-Rural Development of China (No. 2009-K7-11)+2 种基金the Open Fund from State Key Laboratory of Pollution Control and Resource Reuse of Nanjing University (No.PCRRF11004)the Fundamental Research Funds for the Central Universities (No. 1105020504,1116020510)the Scientific Research Foundation of Graduate School of Nanjing University (No. 2012CL06)
文摘A series of biodegradable amphoteric chitosan-based flocculants （3-chloro-2-hydroxypropyl trimethyl ammonium chloride （CTA） modified carboxymethyl chitosan, denoted as CMC-CTA） with different substitution degrees of CTA were prepared successfully. The content of carboxymethyl groups in each CMC-CTA sample was kept almost constant. The solubility of the various flocculants showed that, higher cationic content of flocculants caused a better solubility. The flocculation experiments using kaolin suspension as synthetic water at the laboratory scale indicated that the substitution degree of CTA was one of the key factors for the flocculation properties. With the increase of cationic content, the flocculants were demonstrated better flocculation performance and lower dosage requirement. Flocculation kinetics model of particles collisions combining zeta potential and turbidity measurements was employed to investigate the effects of the cationic content of the flocculants on the flocculation properties from the viewpoint of flocculation mechanism in detail. Furthermore, flocculation performance using raw water from Zhenjiang part of Yangtze River at the pilot scale showed the similar effects to those at the laboratory scale.
基金financially supported by the National Natural Science Foundation of China(No.52203209)the State Key Laboratory of Solid Waste Reuse for Building Materials,China(No.SWR-2022-009)the Fundamental Research Funds for the Central Universities,China(No.FRF-IDRY22-012)。
文摘Silver nanoparticles(Ag NPs)have attracted attention in the field of biomaterials due to their excellent antibacterial property.However,the reducing and stabilizing agents used for the chemical reduction of Ag NPs are usually toxic and may cause water pollution.In this work,Ag NPs(31.2 nm in diameter)were prepared using the extract of straw,an agricultural waste,as the reducing and stabilizing agent.Experimental analysis revealed that the straw extract contained lignin,the structure of which possesses phenolic hydroxyl and methoxy groups that facilitate the reduction of silver salts into Ag NPs.The surfaces of Ag NPs were negatively charged due to the encapsulation of a thin layer of lignin molecules that prevented their aggregation.After the prepared Ag NPs were added to the precursor solution of acrylamide,free radical polymerization was triggered without the need for extra heating or light irradiation,resulting in the rapid formation of an Ag NP-polyacrylamide composite hydrogel.The inhibition zone test proved that the composite hydrogel possessed excellent antibacterial ability due to the presence of Ag NPs.The prepared hydrogel may have potential applications in the fabrication of biomedical materials,such as antibacterial dressings.
基金The authors wish to thank the National Natural Science Foundation of China(No.51773188)the Natural Science Foundation of Shandong Province(No.ZR2017MC072)+3 种基金the National Key Research and Development Program(No.2018YFC1105602)the Key Research and Development Program of Shandong Province(No.2016YYSP018)the Second Maker Program of Marine Biomedical Research Institute of Qingdao(No.MGTD20170002M)the Scientific and Technological Innovation Project Financially Supported by Qingdao National Laboratory for Marine Science and Technology(No.2015ASKJ02).
文摘STAT3 plays a particularly important role in several cancer-related signal transduction pathways.Silencing STAT3 via RNA interference or small molecule inhibitors induces the apoptosis of tumor cells,thereby inhibiting the growth of the tumors.In this study,short-hairpin RNA sequences targeting the STAT3 genes were designed,synthesized,and then connected to pGPU6/GFP/Neo plasmids as the shRNA-expression vectors.The expression of STAT3-shRNA was analyzed by real-time PCR,western blotting,and cell apoptosis assay to study the growth and apoptosis of the cells.Then,the effect of STAT3 knockdown on the NCI-H1650 cells was studied in a tumor mouse model.The results revealed that,after an in vitro transfection,the proliferation of NCI-H1650 cells was inhibited,and the cells were induced to apoptosis.The mRNA and protein expression levels of STAT3 were downregulated in the STAT3-shRNA group.In vivo,the tumor mass and volume in the STAT3-shRNA group were significantly lower than in the other two groups.Both the in vivo and in vitro results demonstrated a long-period inhibiting effect on NSCLC,especially in vivo,when the tumor inhibition rate could reach 50%in the STAT3-shRNA group,which is an exciting outcome.Moreover,the study of the conjugation of STAT3-shRNA and chitosan-based vectors revealed that they could be combined steadily with good cytocompati-bility and transfection efficiency.These results together provide convincing evidence for the application of STAT3-shRNA used in the treatment of non-small lung cancer,which could be a promoting prospect for the development of gene therapy.
