[Objective] This study aimed to explore the protoplast preparation and re- generation conditions of Tremella aurantialba. [Method] Optimal combination of five factors affecting the protoplast preparation and regenerat...[Objective] This study aimed to explore the protoplast preparation and re- generation conditions of Tremella aurantialba. [Method] Optimal combination of five factors affecting the protoplast preparation and regeneration of Tremella aurantialba was selected by using orthogonal experiment, including enzyme system, culture age, enzymolysis temperature, enzymolysis duration and osmotic stabilizer. [Result] The results showed that there were three release modes of Tremella aurantialba proto- plasts: release from top in the early period of enzymolysis, release from the side and release in situ. The optimal protoplast preparation condition was selecting mycelium cultured in liquid medium for 3 d, for enzymolysis in mixed enzyme solu- tion containing 1% of cellulase +1% of snailase +1% of lywallzyme at 36 ℃; for 4 h, with 0.6 mol/L sucrose as osmotic stabilizer, and the obtained preparation rate had reached 1.76 ×10^7 protoplasts/ml. The optimal regeneration condition was using mycelium cultured in liquid medium for 5 d, for enzymolysis in enzyme solution con- taining 1.5% of lywallzyme at 33 ℃ for 3 h, with 0.6 mol/L sucrose as osmotic sta- bilizer, and the regeneration rate had reached 0.22%. [Conclusion] This study provid- ed valuable support for protoplast fusion, ultraviolet mutation breeding and genetic engineering research.展开更多
We introduce a low-cost and effective technique that can transform waste cement-based dust into a superhydrophobic coating with dirt pickup resistance. An organic-inorganic hybrid superhydrophobic coating is prepared ...We introduce a low-cost and effective technique that can transform waste cement-based dust into a superhydrophobic coating with dirt pickup resistance. An organic-inorganic hybrid superhydrophobic coating is prepared by the sol-gel method using methyltriethoxysilane as a precursor and waste cement-based dust as a film-forming material. Orthogonal experiments and a comprehensive scoring method were used to optimize the composition and production technologies. Our results show that this superhydrophobic organic-inorganic hybrid coating has an average static contact angle of 151.65° and low water adhesion. Related tests reveal that the dirt pickup resistance, washing resistance and film-substrate cohesion of this coating are also outstanding. The multi-scale physical and chemical mechanisms behind the properties of the coating are investigated. This recycled cement-based coating can be used as the external cover of engineering structures to protect them from corrosion.展开更多
The objective of this paper is to design a based on composite membrane with certain mechanical porous polyvinyl alcohol (PVA) strength and biocompatibilities serving as tissue regenerative scaffolds. PVA-glycosamino...The objective of this paper is to design a based on composite membrane with certain mechanical porous polyvinyl alcohol (PVA) strength and biocompatibilities serving as tissue regenerative scaffolds. PVA-glycosaminoglycan (GAG)-type I collagen (COL) composite membrane was fabricated by PVA with different molecular weight (Mw) and alcoholysis degree (AD) being blended with certain amounts of GAG and COL and dried at 38~C for 24 h. The water content of the composite membranes were from 61.9% to 95.1% and swelling ratio ranged from 123.6% to 621.7%. Scanning electron micro- scope (SEM) analysis proved that PVA-GAG-COL composite membrane has porous and homogenous structure. Biocompatibility test results showed that the composite membrane was nontoxic, which could promote adhesion and proliferation of fibroblasts on the com- posite membrane. In conclusion, PVA-GAG-COL composite membrane with high water content and swelling ratio, suitable mechanical strength and good biocompatibility, has potential in tissue engineering and regenerative medicine.展开更多
Guided bone regeneration(GBR)is a therapeutic procedure used to enhance alveolar bone volume before dental implants.Commercial non-absorbable membranes(i.e.,titanium membranes)typically require a second surgery to rem...Guided bone regeneration(GBR)is a therapeutic procedure used to enhance alveolar bone volume before dental implants.Commercial non-absorbable membranes(i.e.,titanium membranes)typically require a second surgery to remove,whereas absorbable membranes(i.e.,collagen membranes)will fail when put over extensive bone lesions due to their low mechanical strength.The GBR membrane that has been sought is still being developed.Biodegradable metals(BMs),particularly Mg and Zn,have recently been postulated as promising barrier membrane candidates.Herein,the goal of this research is to evaluate the mechanical and biological feasibility of using BMs as GBR membranes.It shows that BMs have a wide range of potential applications as GBR membranes,owing to their benign biocompatibility,sufficient mechanical support,tunable degradation rate,good osteogenic capabilities,broad-spectrum antibacterial behavior,and improved wound healing ability.The rapid degradation rate,hydrogen evolution impact,and stress corrosion cracking behavior all pose obstacles to the use of Mg-based membranes,which can be improved by surface modifications,heat treatment,alloying,etc.Due to its acceptable degradation rate and lack of gas production,Zn appears to be a better candidate for usage as a GBR membrane.In general,advances in the development of BMs have paved the door for BMs to be used as GBR membranes in oral clinical trials.展开更多
文摘[Objective] This study aimed to explore the protoplast preparation and re- generation conditions of Tremella aurantialba. [Method] Optimal combination of five factors affecting the protoplast preparation and regeneration of Tremella aurantialba was selected by using orthogonal experiment, including enzyme system, culture age, enzymolysis temperature, enzymolysis duration and osmotic stabilizer. [Result] The results showed that there were three release modes of Tremella aurantialba proto- plasts: release from top in the early period of enzymolysis, release from the side and release in situ. The optimal protoplast preparation condition was selecting mycelium cultured in liquid medium for 3 d, for enzymolysis in mixed enzyme solu- tion containing 1% of cellulase +1% of snailase +1% of lywallzyme at 36 ℃; for 4 h, with 0.6 mol/L sucrose as osmotic stabilizer, and the obtained preparation rate had reached 1.76 ×10^7 protoplasts/ml. The optimal regeneration condition was using mycelium cultured in liquid medium for 5 d, for enzymolysis in enzyme solution con- taining 1.5% of lywallzyme at 33 ℃ for 3 h, with 0.6 mol/L sucrose as osmotic sta- bilizer, and the regeneration rate had reached 0.22%. [Conclusion] This study provid- ed valuable support for protoplast fusion, ultraviolet mutation breeding and genetic engineering research.
基金supported by the National Natural Science Foundation of China(Grant Nos.51378113 and 51438003)the National Basic Research Program of China("973"Project)(Grant No.2015CB655102)
文摘We introduce a low-cost and effective technique that can transform waste cement-based dust into a superhydrophobic coating with dirt pickup resistance. An organic-inorganic hybrid superhydrophobic coating is prepared by the sol-gel method using methyltriethoxysilane as a precursor and waste cement-based dust as a film-forming material. Orthogonal experiments and a comprehensive scoring method were used to optimize the composition and production technologies. Our results show that this superhydrophobic organic-inorganic hybrid coating has an average static contact angle of 151.65° and low water adhesion. Related tests reveal that the dirt pickup resistance, washing resistance and film-substrate cohesion of this coating are also outstanding. The multi-scale physical and chemical mechanisms behind the properties of the coating are investigated. This recycled cement-based coating can be used as the external cover of engineering structures to protect them from corrosion.
基金National Natural Science Foundation of China,grant number:51070853Guangzhou Technology Plans,grant number:2010B103315 and 2010J-E041
文摘The objective of this paper is to design a based on composite membrane with certain mechanical porous polyvinyl alcohol (PVA) strength and biocompatibilities serving as tissue regenerative scaffolds. PVA-glycosaminoglycan (GAG)-type I collagen (COL) composite membrane was fabricated by PVA with different molecular weight (Mw) and alcoholysis degree (AD) being blended with certain amounts of GAG and COL and dried at 38~C for 24 h. The water content of the composite membranes were from 61.9% to 95.1% and swelling ratio ranged from 123.6% to 621.7%. Scanning electron micro- scope (SEM) analysis proved that PVA-GAG-COL composite membrane has porous and homogenous structure. Biocompatibility test results showed that the composite membrane was nontoxic, which could promote adhesion and proliferation of fibroblasts on the com- posite membrane. In conclusion, PVA-GAG-COL composite membrane with high water content and swelling ratio, suitable mechanical strength and good biocompatibility, has potential in tissue engineering and regenerative medicine.
基金supported by the National Key R&D Program of China(2018YFC1106600)the National Natural Science Foundation of China(52071008,and U20A20390)Beijing Natural Science Foundation(2192027)。
文摘Guided bone regeneration(GBR)is a therapeutic procedure used to enhance alveolar bone volume before dental implants.Commercial non-absorbable membranes(i.e.,titanium membranes)typically require a second surgery to remove,whereas absorbable membranes(i.e.,collagen membranes)will fail when put over extensive bone lesions due to their low mechanical strength.The GBR membrane that has been sought is still being developed.Biodegradable metals(BMs),particularly Mg and Zn,have recently been postulated as promising barrier membrane candidates.Herein,the goal of this research is to evaluate the mechanical and biological feasibility of using BMs as GBR membranes.It shows that BMs have a wide range of potential applications as GBR membranes,owing to their benign biocompatibility,sufficient mechanical support,tunable degradation rate,good osteogenic capabilities,broad-spectrum antibacterial behavior,and improved wound healing ability.The rapid degradation rate,hydrogen evolution impact,and stress corrosion cracking behavior all pose obstacles to the use of Mg-based membranes,which can be improved by surface modifications,heat treatment,alloying,etc.Due to its acceptable degradation rate and lack of gas production,Zn appears to be a better candidate for usage as a GBR membrane.In general,advances in the development of BMs have paved the door for BMs to be used as GBR membranes in oral clinical trials.