Zeolites have been widely used as catalysts,ion-exchangers,and adsorbents in chemical industries,detergent industry,steel industry,glass industry,ceramic industry,medical and healthfield,and environmentalfield,and recen...Zeolites have been widely used as catalysts,ion-exchangers,and adsorbents in chemical industries,detergent industry,steel industry,glass industry,ceramic industry,medical and healthfield,and environmentalfield,and recently applied in energy storage.Seed-assisted synthesis is a very effective approach in promoting the crystallization of zeolites.In some cases,the target zeolite cannot be formed in the absence of seed zeolite.In homologous seed-assisted synthesis,the structure of the seed zeolite is the same to that of the target zeolite,while the structure of the seed zeolite is different to that of the target zeolite in the heterologous seed-assisted synthesis.In this review,we briefly summarized the heterologous seed-assisted syntheses of zeolites and analyzed the structure-directing effect of heterologous seeds and surveyed the“common composite building units(CBUs)hypothesis”and the“common secondary building units(SBUs)hypothesis”.However,both hypotheses cannot explain all observations on the heterologous seed-assisted syntheses.Finally,we proposed that the formation of the target zeolite does need nuclei with the structure of target zeolite and the formation of the nuclei of the target zeolite can be promoted by either the undissolved seed crystals with the same CBUs or SBUs to the target zeolite or by the facilitated appropriate distribution of the specific building units due to the presence of the heterologous seed that does not have any common CBUs and SBUs with the target zeolite.展开更多
Small heat shock proteins(sHSPs)act as molecular chaperones that can prevent the accumulation of damaged proteins during abiotic stress,especially heat shock,but the mechanism is not clear.To study the function of sHS...Small heat shock proteins(sHSPs)act as molecular chaperones that can prevent the accumulation of damaged proteins during abiotic stress,especially heat shock,but the mechanism is not clear.To study the function of sHSPs in Lenzites gibbosa,a common polypore in northern temperate forests that causes spongy white rot of broadleaf trees,under temperature stress,L.gibbosa mycelia were grown at 25℃ for 9 d,treated at 33℃ for 15,30,60,and 120 min before sequencing the transcriptomes.From among 32 heat shock protein(HSP)genes found in the screen of the transcriptome data,a highly expressed gene was cloned and named Lghsp17.4.RT-qPCR was used to analyze the expression of the gene Lghsp17.4 under heat shock and dye stress.Both treatments induced higher expression of Lghsp17.4 at the transcriptional level,indicating that Lghsp17.4 might function in the response to heat stress and dye degradation.We previously found that L.gibbosa generally had a heat shock reaction(HSR)during degradation of aromatic compounds,and HSPs were always produced with manganese peroxidases(MnPs)and other lignin-degrading enzymes.Therefore,we measured the activity of MnPs in L.gibbosa after 33℃ heat shock to analyze the relationship between MnPs expression and Lghsp17.4 expression.Heat shocks of 0–30 min increased MnPs activity,and the change in MnPs activity were closely positively correlated with the expression levels of Lghsp17.4 over time,indicating a potential connection and interaction between LgHSP17.4 and MnPs during the HSR in L.gibbosa.Thus,LgHSP17.4 might have a positive regulatory effect on the HSR in L.gibbosa and be a critical component of a stress resistance mechanism.展开更多
Catalpa fargesii is an important economic tree species used for furniture and timber production because of its high density and hardness.Its survival and growth are severely aff ected and primarily limited by drought ...Catalpa fargesii is an important economic tree species used for furniture and timber production because of its high density and hardness.Its survival and growth are severely aff ected and primarily limited by drought stress.Thus,to better understand the mechanism of drought resistance in C.fargesii,we used qRT-PCR to reveal signifi cantly diff erent expression of three plasma membrane intrinsic protein genes:CfPIP1-1,CfPIP1-2 and CfPIP1-4.We then cloned their full-length cDNA sequences and characterized the encoded proteins.We analyzed the genes phylogenetically and predicted conserved motifs,domains,and secondary and tertiary structures.To verify the function ofthe CfPIP1 genes further,we ectopically expressed CfPIP1 transgenes in Arabidopsis thaliana.The results showed that CfPIP1-1,CfPIP1-2 and CfPIP1-4 had several characteristics of aquaporins.The transgenic plants grew better than the WT plants did under drought stress,and overexpression of the CfPIP1 genes increased the plant water content and resistance to drought.Thus,CfPIP1-1,CfPIP1-2 and CfPIP1-4 of C.fargesii play key roles in regulating the intracellular and extracellular water balance and in mediating the plant response to drought.展开更多
Objective: To study the efficacy of combined use of a new grafting material, new reconstituted bone xenograft (NRBX) and free periosteal graft in repair of segmental bony defects. Methods: NRBX was made by combining r...Objective: To study the efficacy of combined use of a new grafting material, new reconstituted bone xenograft (NRBX) and free periosteal graft in repair of segmental bony defects. Methods: NRBX was made by combining recombi- nant human BMP2(rhBMP2) and an antigen-free bovine cancellous bone (BCB) as a carrier. NRBX was used alone, in combination with free periosteal graft to repair a 1. 5 cm defect in the radius of rabbit. The defect-repairing capability for each of the treatment modalities was assessed with radiographical, biomechanical, densitometrical and histological methods. Results: NRBX used alone was capable of healing the defect in large by 16 weeks, with a similar repair process and mecha- nism seen with econstituted bone xenograft (RBX). Combined use of NRBX and free periosteal graft was superior in terms of increased and quality of the new bone formed at the early stage of the repair pass (within 12 weeks) to NRBX used alone, with the defect basically healed by 12 weeks. Conclusion: Both methods are effective in repairing segmental bone defects, but NRBX used in combination with free periosteal graft is preferred, because of the satisfactory osteogenesis, osteoconduction and osteoinduction.展开更多
基金support from the National Key Research and Development Program of China(2021YFA1500401,2021YFA1501202)the National Natural Science Foundation of China(22288101)the 111 Project(B17020)for supporting this work.
文摘Zeolites have been widely used as catalysts,ion-exchangers,and adsorbents in chemical industries,detergent industry,steel industry,glass industry,ceramic industry,medical and healthfield,and environmentalfield,and recently applied in energy storage.Seed-assisted synthesis is a very effective approach in promoting the crystallization of zeolites.In some cases,the target zeolite cannot be formed in the absence of seed zeolite.In homologous seed-assisted synthesis,the structure of the seed zeolite is the same to that of the target zeolite,while the structure of the seed zeolite is different to that of the target zeolite in the heterologous seed-assisted synthesis.In this review,we briefly summarized the heterologous seed-assisted syntheses of zeolites and analyzed the structure-directing effect of heterologous seeds and surveyed the“common composite building units(CBUs)hypothesis”and the“common secondary building units(SBUs)hypothesis”.However,both hypotheses cannot explain all observations on the heterologous seed-assisted syntheses.Finally,we proposed that the formation of the target zeolite does need nuclei with the structure of target zeolite and the formation of the nuclei of the target zeolite can be promoted by either the undissolved seed crystals with the same CBUs or SBUs to the target zeolite or by the facilitated appropriate distribution of the specific building units due to the presence of the heterologous seed that does not have any common CBUs and SBUs with the target zeolite.
基金supported by the Fundamental Research Funds for the Central Universities(Grant No.:2572016AA04)Northeast Asia Biodiversity Research Center Double First class Funds(Grant No.:411146030416 and No.:411147021003).
文摘Small heat shock proteins(sHSPs)act as molecular chaperones that can prevent the accumulation of damaged proteins during abiotic stress,especially heat shock,but the mechanism is not clear.To study the function of sHSPs in Lenzites gibbosa,a common polypore in northern temperate forests that causes spongy white rot of broadleaf trees,under temperature stress,L.gibbosa mycelia were grown at 25℃ for 9 d,treated at 33℃ for 15,30,60,and 120 min before sequencing the transcriptomes.From among 32 heat shock protein(HSP)genes found in the screen of the transcriptome data,a highly expressed gene was cloned and named Lghsp17.4.RT-qPCR was used to analyze the expression of the gene Lghsp17.4 under heat shock and dye stress.Both treatments induced higher expression of Lghsp17.4 at the transcriptional level,indicating that Lghsp17.4 might function in the response to heat stress and dye degradation.We previously found that L.gibbosa generally had a heat shock reaction(HSR)during degradation of aromatic compounds,and HSPs were always produced with manganese peroxidases(MnPs)and other lignin-degrading enzymes.Therefore,we measured the activity of MnPs in L.gibbosa after 33℃ heat shock to analyze the relationship between MnPs expression and Lghsp17.4 expression.Heat shocks of 0–30 min increased MnPs activity,and the change in MnPs activity were closely positively correlated with the expression levels of Lghsp17.4 over time,indicating a potential connection and interaction between LgHSP17.4 and MnPs during the HSR in L.gibbosa.Thus,LgHSP17.4 might have a positive regulatory effect on the HSR in L.gibbosa and be a critical component of a stress resistance mechanism.
基金Fundamental Research Funds of Chinese Academy of Forestry(CAFYBB2014QA004).
文摘Catalpa fargesii is an important economic tree species used for furniture and timber production because of its high density and hardness.Its survival and growth are severely aff ected and primarily limited by drought stress.Thus,to better understand the mechanism of drought resistance in C.fargesii,we used qRT-PCR to reveal signifi cantly diff erent expression of three plasma membrane intrinsic protein genes:CfPIP1-1,CfPIP1-2 and CfPIP1-4.We then cloned their full-length cDNA sequences and characterized the encoded proteins.We analyzed the genes phylogenetically and predicted conserved motifs,domains,and secondary and tertiary structures.To verify the function ofthe CfPIP1 genes further,we ectopically expressed CfPIP1 transgenes in Arabidopsis thaliana.The results showed that CfPIP1-1,CfPIP1-2 and CfPIP1-4 had several characteristics of aquaporins.The transgenic plants grew better than the WT plants did under drought stress,and overexpression of the CfPIP1 genes increased the plant water content and resistance to drought.Thus,CfPIP1-1,CfPIP1-2 and CfPIP1-4 of C.fargesii play key roles in regulating the intracellular and extracellular water balance and in mediating the plant response to drought.
文摘Objective: To study the efficacy of combined use of a new grafting material, new reconstituted bone xenograft (NRBX) and free periosteal graft in repair of segmental bony defects. Methods: NRBX was made by combining recombi- nant human BMP2(rhBMP2) and an antigen-free bovine cancellous bone (BCB) as a carrier. NRBX was used alone, in combination with free periosteal graft to repair a 1. 5 cm defect in the radius of rabbit. The defect-repairing capability for each of the treatment modalities was assessed with radiographical, biomechanical, densitometrical and histological methods. Results: NRBX used alone was capable of healing the defect in large by 16 weeks, with a similar repair process and mecha- nism seen with econstituted bone xenograft (RBX). Combined use of NRBX and free periosteal graft was superior in terms of increased and quality of the new bone formed at the early stage of the repair pass (within 12 weeks) to NRBX used alone, with the defect basically healed by 12 weeks. Conclusion: Both methods are effective in repairing segmental bone defects, but NRBX used in combination with free periosteal graft is preferred, because of the satisfactory osteogenesis, osteoconduction and osteoinduction.