查找使用阿拉丁产品的科研文献

Hypoxia-responsive microgels act as an intra-articular lubricant and inflammatory inhibitor for osteoarthritis therapy

Zhaoyi Wang,Shun-Yu Yao,Yuxiang Zhang,Shifen Li,Tong Zhou,Shuqin Wang,Dong-Sheng Guo,Changyou Gao

The reduced oxygen concentration is a distinctive feature of osteoarthritic (OA) cartilage, whereas the mechanical friction also contributes to the inflammatory hypoxia microenvironment of OA. Herein, novel hypoxia-responsive methylprednisolone (MP) delivery microgels combining the capability of reactive oxygen species (ROS)-depletion and lubrication were constructed for regulating the microenvironment of OA. Methacrylate-modified sulfonated azocalix[4] arene (MACA) loaded with MP, the copolymers consisting of bioinspired lubricant 2-methacryloxyethyl phosphorylcholine (MPC), and polyethylene glycol-modified ROS-responsive poly(thioketal) (PEG-4PTK) were crosslinked together to construct the microgels. The zwitterionic MPC offered a lubrication effect, while the ROS-elimination was contributed by the PTK segments and the phenol groups in MACA. The microgels responsively released cargos in inflammatory environment and decreased inflammation by inhibiting the production of ROS and regulating the expression of inflammatory cytokines, and showed the lowest hypoxia-inducible factor-1α (HIF-1α) positive area and presented more deposition of glycosaminoglycans and collagen II with a smoother and integrated cartilage structure in therapy of OA in rats in vivo .

Decoding the Functionality of pESA3 in Cronobacter sakazakii: A Balancing Act between Survival and Pathogenicity

Ping Lu,Juan Xue,Aiying Shi,Xuemeng Ji

Purpose Cronobacter sakazakii is a foodborne pathogen notable for both virulence and desiccation tolerance. This study investigates the functional roles of the pESA3 plasmid in mediating these two traits and explores the potential trade-off between them. Methods Proteomic profiling identified pESA3 -encoded proteins, followed by construction of targeted deletion mutants ( hcp , ESA_pESA3p05542 ) and a plasmid-cured strain. Phenotypic assays evaluated growth, desiccation survival, surface hydrophilicity, and virulence in a neonatal rat model. Results Deletion of ESA_pESA3p05542 impaired desiccation tolerance and reduced surface hydrophilicity, while hcp deletion attenuated virulence but enhanced desiccation survival. Notably, complete loss of pESA3 abolished virulence without affecting desiccation resistance, suggesting functional antagonism between plasmid-encoded virulence and stress-response genes. Conclusions pESA3 enables C. sakazakii to balance host pathogenicity and environmental persistence. Its gene modules promote either virulence or desiccation resistance, but not both, reflecting an evolutionary trade-off that supports survival across diverse niches.

Gambogic acid-loaded PEG–PCL nanoparticles act as an effective antitumor agent against gastric cancer

Dinghu Zhang,Zhengyun Zou,Wei Ren,Hanqing Qian,Qianfeng Cheng,Liulian Ji,Baorui Liu,Qin Liu

2D/2D porous Co3O4/rGO nanosheets act as an electrochemical sensor for voltammetric tryptophan detection

Shiqi Zhang,Peidong Ling,Yi Chen,Jun Liu,Chun Yang

Herein, 2D/2D porous Co 3 O 4 nanosheets/rGO composites modified GCE (Co 3 O 4 /rGO/GCE) were proposed for electrochemical detection of tryptophan (Trp). The surface morphology and structure of Co 3 O 4 /rGO nanosheets were carried out using SEM, XRD , and Raman spectra . Electrochemical performance of Trp on as-synthesized modified electrodes were discussed by CV and EIS techniques. Moreover, the best electrochemical property was also investigated by varying test condition detailedly. Consequently, oxidation peak intensity and current density were 130.3 μA and 336.7 μA·cm −2 on Co 3 O 4 /rGO/GCE at working potential of 0.78 V ( vs. SCE electrode), respectively. They were more than 23-times greater than these on bare GCE in electrochemical detection of Trp. It was attributed to the synergy effect of 2D porous Co 3 O 4 nanosheets (high catalytic activity) and 2D rGO nanosheets (large electrochemical active area). After the optimization, wide linear determination ranges (from 1.0 to 800 μM) and low LOD of 0.26 μM (S/N = 3) were acquired. In addition, these electrodes were further successfully applied to the determination of Trp in commercial amino acid injection samples. This 2D porous Co 3 O 4 /rGO modified GCE sensor could provide a slight view on the design of 2D/2D composite materials with high electrochemical properties.

Pickering emulsion co-delivery system: Stimuli-responsive biomineralized particles act as particulate emulsifiers and bioactive carriers

Haoyue Hou,Yuli Zhang,Yu Liu,Qi Zeng,Qinyuan Li,Xingyuan Fang,Ting Guo,Hao Yuan,Sa Zeng,Tao Meng

Pickering emulsions provide a promising platform for the efficient delivery of bioactive. However, co-delivery of fragile bioactives with different physicochemical properties for comprehensive effects still faces practical challenges due to the limited protection for bioactives and the lack of stimuli-responsive property for on-demand release. Herein, a stimuli-responsive co-delivery system is developed based on biomineralized particles stabilized Pickering emulsions. In this tailor co-delivery system, hydrophilic bioactive (pepsin) with the fragile structure is encapsulated and immobilized by biomineralization, the obtained biomineralized particles (PPS@CaCO 3 ) are further utilized as emulsifiers to form O/W Pickering emulsions, in which the hydrophobic oxidizable bioactive (curcumin) is stably trapped into the dispersed phase. The results show that two bioactives are successfully co-encapsulated in Pickering emulsions, and benefiting from the protection capacities of biomineralization and Pickering emulsions, the activity of pepsin and curcumin shows a 7.33-fold and 144.83-fold enhancement compared to the free state, respectively. Moreover, In vitro study demonstrates that Pickering emulsions enable to co-release of two bioactives with high activity retention by the acid-induced hydrolyzation of biomineralized particles. This work provides a powerful stimuli-responsive platform for the co-delivery of multiple bioactive compounds, enabling high activity of bioactives for the comprehensive health effects.

Small organic molecules act as a trigger in an “unzippering” mechanism to facilitate carbon nanotube dispersion

Lin Shi,Di Zhang,Jinfeng Zhao,Mengnan Yin,Aiping Liang,Saikat Ghosh

In binary dispersing agents system, the contribution and roles of different sized molecules to carbon nanotubes (CNTs) dispersion remain unclear, which hinders the understanding of the environmental behaviour and risks of CNTs. This study compared the dispersion of CNTs by m-nitrobenzoic acid (NBA), trans-cinnamic acid (TCA), tannic acid (TA), and their mixtures. The dispersion efficiency of CNTs significantly reduced with the increased solid-phase concentration ( Q e ) of TA due to the adsorption of TA on newly exposed CNTs surfaces. However, the CNTs dispersion efficiency by NBA or TCA was independent of Q e because the dispersed CNTs surface was completely occupied by NBA or TCA without new exposed sites available for subsequent adsorption. The mixture of NBA or TCA with TA significantly enhanced the dispersion efficiency of CNTs, indicating a synergistic effect of CNTs dispersion. The addition of NBA or TCA decreased the hydrodynamic diameter of CNTs dispersed by TA, which indicated that NBA or TCA facilitated TA wedging into CNTs bundles for more complete separation of CNTs. This study highlighted the triggering effect of small molecules in the “unzippering” mechanism for improving the dispersing efficiency of CNTs by large molecules.

Eucommia ulmoides Leaf Polysaccharide in Conjugation with Ovalbumin Act as Delivery System Can Improve Immune Response

Haibo Feng,Jie Yang,Hui Zhi,Xin Hu,Yan Yang,Linzi Zhang,Qianqian Liu,Yangyang Feng,Daiyan Wu,Hangyu Li

In this investigation, to maximize the desired immunoenhancement effects of PsEUL and stimulate an efficient humoral and cellular immune response against an antigen, PsEUL and the model antigen ovalbumin (OVA) were coupled using the N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (EDC) reaction to yield a novel delivery system (PsEUL-OVA). The physicochemical characteristics and immune regulation effects of this new system were investigated. We found the yield of this EDC method to be 46.25%. In vitro, PsEUL-OVA (200 μg mL−1) could enhance macrophage proliferation and increase their phagocytic efficiency. In vivo, PsEUL-OVA could significantly increase the levels of OVA-specific antibody (IgG, IgG1, IgG2a, and IgG2b) titers and cytokine (IL-2, IL-4, IL-6, IFN-γ) levels. Additionally, it could activate T lymphocytes and facilitate the maturation of dendritic cells (DCs). These findings collectively suggested that PsEUL-OVA induced humoral and cellular immune responses by promoting the phagocytic activity of macrophages and DCs. Taken together, these results revealed that PsEUL-OVA had the potential to improve immune responses and provide a promising theoretical basis for the design of a novel delivery system.Keywords:polysaccharides fromEucommia ulmoides;adjuvant;delivery system;macrophage;dendritic cell

Microenvironment responsive charge-switchable nanoparticles act on biofilm eradication and virulence inhibition for chronic lung infection treatment

Pengyu Li,Jieyi Pan,Yating Dong,Yingying Sun,Yalong Wang,Kang Liao,Yili Chen,Xin Deng,Shihui Yu,Haiyan Hu

Chronic pulmonary infection caused by Pseudomonas aeruginosa ( P. aeruginosa ) is a common lung disease with high mortality, posing severe threats to public health. Highly resistant biofilm and intrinsic resistance make P. aeruginosa hard to eradicate, while powerful virulence system of P. aeruginosa may give rise to the recurrence of infection and eventual failure of antibiotic therapy. To address these issues, infection-microenvironment responsive nanoparticles functioning on biofilm eradication and virulence inhibition were simply prepared by electrostatic complexation between dimethylmaleic anhydride (DA) modified negatively charged coating and epsilon-poly( l -lysine) derived cationic nanoparticles loaded with azithromycin (AZI) (DA-AZI NPs). Charge reversal responsive to acidic condition enabled DA-AZI NPs to successively penetrate through both mucus and biofilms, followed by targeting to P. aeruginosa and permeabilizing its outer/inner membrane. Then in situ released AZI, which was induced by the lipase-triggered NPs dissociation, could easily enter into bacteria to take effects. DA-AZI NPs exhibited enhanced eradication activity against P. aeruginosa biofilms with a decrease of >99.999% of bacterial colonies, as well as remarkable inhibitory effects on the production of virulence factors and bacteria re-adhesion & biofilm re-formation. In a chronic pulmonary infection model, nebulization of DA-AZI NPs into infected mice resulted in prolonged retention and increased accumulation of the NPs in the infected sites of the lungs. Moreover, they significantly reduced the burden of P. aeruginosa , effectively alleviating lung tissue damages and inflammation. Overall, the proposed DA-AZI NPs highlight an innovative strategy for treating chronic pulmonary infection.

Hyaluronic acid act as drug self-assembly chaperone and co-assembled with celalstrol for ameliorating non-alcoholic steatohepatitis

Tianye Zheng,Xuelan Gan,Jianguo Luo,Zhongbo Shi,Yunfei Zhao,Yan Wang,Jun Chen,Chao Yu

Nanoformulations of therapeutic drugs with diverse chemical structures are often complex to produce and lack a universal synthesis approach. Herein, we demonstrate that hyaluronic acid (HA) can function as an assembly chaperone, facilitating the formulation of various chemical compounds into nanoparticles without necessitating chemical modification. As a proof of concept, celastrol-HA co-assembled nanoparticles (CHNPs) were synthesized and utilized in the multifactorial treatment of non-alcoholic steatohepatitis (NASH). By simply blending an aqueous solution of HA and celastrol, we achieved the formation of homogeneous, stable, and biocompatible nanoparticles, effectively addressing the critical issues associated with celastrol's poor water solubility and high systemic toxicity. of celastrol. Ex vivo and in vivo experiments demonstrated that CHNPs ameliorated NASH by inhibiting macrophage M1 polarization, reducing liver inflammation and lipid deposition, and improving metabolic disorders. Furthermore, CHNPs reduced systemic toxicity and enhanced the bioavailability of celastrol. The simplicity of the HA-based nanoparticles may facilitate the development of translational nanomedicines.

Iron–silver-modified quantum dots act as efficient catalysts in anti-cancer multitherapy through controlled, ultrasound-induced oxidation

Wang Dong,Ji Lei,Li You,Xu Meng,Wang Hao,Brovelli Sergio,Qiao Zeng-Ying,Zhang Jiatao,Li Yadong

Chemodynamic therapy and sonodynamic therapy are two promising tumour therapeutic strategies. However, lack of highly effective sonosensitizers and control over chemodynamic therapy limit their application. Here we synthesize silver-doped zinc selenide quantum dots with atomically dispersed superficial Fe and show that they act as efficient sonosensitizers, catalysers and immunoreagents. Surface modification with an in situ self-assembly peptide drives accumulation in tumours. Superficial Fe III remains stable and converts to Fe II only under ultrasonic processing, reverting to Fe III upon ultrasound cessation. Under ultrasound stimulation, superficial Fe undergoes valence change with concomitant amelioration of the hypoxic tumour microenvironment and production of sonodynamic therapy-beneficial hydroxyl radicals. Furthermore, silver doping suppressed nonradiative recombination of excitons, leading to improved production of singlet oxygen. Meanwhile, selenium promotes robust systemic immune responses for the inhibition of tumour metastases. This nano-platform allows control of valence switching of atomically dispersed catalysts, representing an effective tool for chemodynamic/sonodynamic/immunotherapy.

Dialdehyde cellulose nanocrystals act as multi-role for the formation of ultra-fine gold nanoparticles with high efficiency

Guifa Xiao,Ying Wang,Hui Zhang,Zhaodong Zhu,Shiyu Fu

Gold nanoparticles (AuNPs) within 10 nm prepared and stabilized by environmentally friendly reducing and supporting agents are highly desired to obtain excellent catalytic properties for organic transformation. In this paper, a rapid and mild strategy for synthesizing ultra-fine AuNPs is reported by using dialdehyde cellulose nanocrystals (DACNCs) as both efficient reductant, dispersant and template for the first time. DACNCs with higher content of aldehyde groups, acting as multi-role player, are crucial to limit the size of AuNPs within 10 nm. Furthermore, AuNPs with average diameter of 5.1 ± 1.0 nm are quantitative obtained at ambient temperature by reducing chloroauric acid within 1 h under conditions of pH= 10.8, 53% aldehyde content, 0.4% DACNCs and 0.25 mM gold ions. In addition, a quantitative method for monitoring the exhaustion of gold ions is established to clarify the synthetic mechanism of AuNPs. Finally, reduction of 4-nitrophenol under AuNPs catalysis is conducted to verify the superiority of as-prepared ultra-fine AuNPs.

CuO–Ru0.3@Co3O4 nanocomposites act as a tandem catalyst for dehydrogenation of ammonia borane and hydrogenation of nitrobenezene

Yong Cheng,Dan Wang,Xiuxiu Wang,Ying-Hua Zhou

The development of catalysts with high activity for tandem reaction are all the ways pursued by chemists. Herein, CuO–Ru 0.3 @Co 3 O 4 has been synthesized and used as efficient tandem catalyst to promote the release of hydrogen from hydrolytic dehydrogenation of ammonia borane (AB) to catalyze the hydrogenation of nitrobenezenes (NBs). The catalyst exhibits the TOF of 29.87 min −1 and provides the apparent activation energy of 45.2 kJ mol −1 for the hydrolytic dehydrogenation of AB. Additionally, benefited from the magnetic separation capability, up to 99% of its initial catalytic activity is retained after four catalytic cycles.