The purpose of this study was to evaluate the use of a biodegradable membrane of polyhydroxybutyrate-hydroxyvalerate copolymer reinforced with polyglactin 910 fibers, as an occlusive barrier over implants placed into fresh extraction sockets. Ten dogs had the 3rd and 4th mandibular premolars extracted bilaterally. Each dog had 4 Astra Dental Implants placed directly into the fresh extraction sockets. The top of the fixtures was placed at the same level as the top of the buccal cortical bone. The two implants in the right side were covered with the hydrolyzable polyester material (polyhydroxybutyrate-hydroxyvalerate reinforced with polyglactin 910 fibers; PHB-HV/PG), and the 2 implants in the left side were controls without occlusive membranes. Soft tissue dehiscences were registered for half of the implants in the test side but were not noted in the control side. The histomorphological measurements after 12 weeks showed that the mean distance from the top of the fixtures to the first bone-to-implant contact was significantly greater than for the control side. The membrane-covered implants without dehiscences showed also significantly less bone fill compared with the control side. Inflammatory cell infiltrates were seen adjacent to all PHB-HV/PG membranes, and frequently the membrane material was surrounded by a fibrous tissue capsule. The polyester membranes used in this study interfered with the marginal bone healing adjacent to the immediately placed implants. An increased inflammatory reaction and significantly less marginal bone healing was registered in the membrane side compared with the control side.
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Angew Chem Int Ed Engl
January 2025
Chang Chun Institute of Applied Chemistry Chinese Academy of Sciences, Key Laboratory of Polymer Ecomaterials, 5625 Renmin Street, Changchun, , 130022, Changchun, CHINA.
Living cationic polymerization (LCP) is a classical technique for precision polymer synthesis; however, due to the high sensitivity of cationic active species towards chain-transfer/termination events, it is notoriously difficult to control polymerization under mild conditions, which inhibits its progress in advanced materials engineering. Here, we unlock a practical anion-binding catalytic strategy to address the historical dilemma in LCP. Our experimental and mechanistic studies demonstrate that commercially accessible hexafluoroisopropanol (HFIP), when used in high loading, can create higher-order HFIP aggregates to tame dormant-active species equilibrium via non-covalent anion-binding principle, in turn inducing distinctive polymerization kinetics behaviors that grant efficient chain propagation while minimizing competitive side reactions.
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Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China. Electronic address:
Adeno-associated viruses (AAV) have significant potential as vaccine carriers due to their excellent biosafety and efficient antigen gene delivery. However, most AAV vaccines show limited capacity to transduce antigen-presenting cells (APCs) following intramuscular injection which may cause inadequate cellular immune responses and undesired side effects due to transducing other tissues or cells. Herein, we developed a soluble microneedle patch for targeting the AAV vaccines to the epidermal and dermal APCs.
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January 2025
The Department of Medical Imaging, Guangzhou Key Laboratory of Molecular Functional Imaging and Artificial Intelligence for Major Brain Diseases, The Affiliated Guangdong Second Provincial General Hospital of Jinan University, Jinan University, Guangzhou 518037 China. Electronic address:
Microwave dynamic therapy (MWDT) destroy tumor cells using reactive oxygen species (ROS), but its effectiveness is limited by low ROS production and intracellular oxygen (O) availability. This study presents a novel strategy using manganese (II) ion (Mn) doped iron (Fe)-based metal-organic framework (Fe MOF) nanoparticles (NPs) to enhance both O generation and ROS production for improved MWDT. Incorporating Mn into Fe MOF narrows the bandgap from 0.
View Article and Find Full Text PDFAdv Sci (Weinh)
January 2025
Department of Surgery, Center for Cancer Medicine, the Fourth Affiliated Hospital of School of Medicine, International School of Medicine, International Institutes of Medicine, Zhejiang University, Yiwu, 322000, China.
Irreversible electroporation (IRE) is a novel local tumor ablation technique that can potentially stimulate immune responses. However, IRE alone cannot effectively activate the immune system or prevent distant metastases. Therefore, this study utilized the biocompatibility of Chlorella vulgaris (C.
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