This study deals with constant-gain adaptive observers for nonlinear systems,for which relatively few solutions are available for some particular cases.We introduce an asymptotic observer of constant gain for nonlinea...This study deals with constant-gain adaptive observers for nonlinear systems,for which relatively few solutions are available for some particular cases.We introduce an asymptotic observer of constant gain for nonlinear systems that have linear input.This allows the observer design to be formulated within the linear matrix inequality paradigm provided that a strictly positive real condition bet ween the inpu t disturbance and the output is fulfilled.The proposed observer is t hen applied to a large class of nonlinear chemos tat dynamical systems that are widely used in the fermentation process,cell cultures,medicine,etc.In fact,under standard practical assumptions,the necessary change of the chemos tat state coordinates exis ts,allowing use of the const ant-gain observer.Finally,the developed theory is illustrated by estimating pollutant concentration in a Spirulina maxima wastewater treatment facility.展开更多
Background:Targeted alpha therapy(TAT)has emerged as a promising strategy for cancer treatment by selectively delivering high linear energy transfer(LET)alpha-emitters to tumor cells while minimizing off-target toxici...Background:Targeted alpha therapy(TAT)has emerged as a promising strategy for cancer treatment by selectively delivering high linear energy transfer(LET)alpha-emitters to tumor cells while minimizing off-target toxicity.However,the clinical translation of alpha-emitters,particularly radium-223(223Ra),remains challenging due to inefficient targeted delivery and uncontrolled release of recoil daughter products,leading to systemic toxicity.Methods:Herein,a dual-locked pretargeted strategy was developed integrating platinumⅣ(PtⅣ)-loaded hydrogel nanoparticles(HNPs)(HAQ@HNPs)and223Ra-loaded HNPs(223Ra@HNPs)into an inverse electron demand Diels-Alder(IEDDA)-activated drug delivery system.In vitro cytotoxicity,ROS,and apoptosis,together with in vivo biodistribution,imaging,and therapeutic studies,were performed to evaluate the therapeutic efficacy and immune activation.Results:This caged dual-locked approach enables precise pretargeted accumulation at the tumor site,followed by rapid dissociation and controlled release of223Ra and PtⅣupon IEDDA-triggered activation,thereby ensuring high tumor specificity while minimizing systemic exposure.The synergistic combination of TAT and chemotherapy effectively disrupts redox homeostasis,induces immunogenic cell death(ICD),and elicits a robust antitumor immune response.Furthermore,when combined with programmed death-ligand 1(PD-L1)blockade,this strategy significantly enhances systemic antitumor immunity,leading to robust inhibition of tumor growth and metastasis.Conclusions:These findings underscore the potential of dual-locked pretargeted strategies to advance TAT by improving therapeutic efficacy and addressing the critical challenge of radionuclide leakage,paving the way for next-generation precision-targeted radiopharmaceuticals.展开更多
Objective To analyze the impact of depletion of the twin arginine translocation (TAT) system on virulence and physiology of Yersinia enterocolitica for a better understanding of its pathogenicity. Methods We constru...Objective To analyze the impact of depletion of the twin arginine translocation (TAT) system on virulence and physiology of Yersinia enterocolitica for a better understanding of its pathogenicity. Methods We constructed a △tatC::Sp^R mutant of Yersinia enterocolitica by P1 phage mediated transduction using Escherichia coli K-12 △tatC::Sp^R strain as a donor. Results A Pl-mediated genetic material transfer was found between the two species of enterobacteria, indicating a great potential of acquisition of antibiotic resistance in emergency of a new threatening pathogen by genetic material exchanges. Periplasmic trimethylamine N-oxidase reductase activity was detected in the wild type E enterocolitica strain and translocation of this enzyme was completely abolished by the △tatC::Sp^R mutation. In addition, the △tatC::Sp^R mutation showed a pleiotropic effect on the metabolism of E enterocolitica. However, the tat mutation did not seem to affect the mobility and virulence of Y. enterocolitica under the conditions used. Conclusion Unlike other pathogenic bacteria studied, the TAT system of E enterocolitica might play an important role in the pathogenic process, which is distinct from other pathogens, such as Pseudomonas aeruginosa and enterohemorrhagic E. coli O 157:H7.展开更多
【目的】研究过表达枯草芽孢杆菌Tat运输途径的Tat Ad Cd转位酶对促进脂肪酶分泌的影响。【方法】用cdd基因的串联启动子和前导区,替换tat AD-CD操纵子的启动子和前导区,并在染色体sac B基因位点整合表达;采用q RT-PCR方法表征tat AD-C...【目的】研究过表达枯草芽孢杆菌Tat运输途径的Tat Ad Cd转位酶对促进脂肪酶分泌的影响。【方法】用cdd基因的串联启动子和前导区,替换tat AD-CD操纵子的启动子和前导区,并在染色体sac B基因位点整合表达;采用q RT-PCR方法表征tat AD-CD操纵子的表达水平;用脂肪酶表达质粒p HP13L转化Tat Ad Cd转位酶过表达菌株,构建产脂肪酶重组菌。通过测定脂肪酶活性,以及聚丙烯酰胺凝胶电泳,考察Tat Ad Cd转位酶过表达对脂肪酶分泌的影响。【结果】tat AD-CD操纵子被过表达,其胞内m RNA相对水平提高了185倍。Tat Ad Cd转位酶的过表达,使脂肪酶发酵单位提高了40%。【结论】使用cdd基因的串联启动子和前导区,能够有效地过表达目的基因;枯草芽孢杆菌脂肪酶可以同时经由Sec途径和Tat途径分泌;过表达Tat Ad Cd转位酶,能够显著提高脂肪酶的分泌量。展开更多
Objective To explore the role of HIV-1 tat gene variations in AIDS dementia complex (ADC) pathogenesis. Methods HIV-1 tat genes derived from peripheral spleen and central basal ganglia of an AIDS patient with ADC an...Objective To explore the role of HIV-1 tat gene variations in AIDS dementia complex (ADC) pathogenesis. Methods HIV-1 tat genes derived from peripheral spleen and central basal ganglia of an AIDS patient with ADC and an AIDS patient without ADC were cloned for sequence analysis. HIV-1 tat gene sequence alignment was performed by using CLUSTAL W and the phylogentic analysis was conducted by using Neighbor-joining with MEGA4 software. All tat genes were used to construct recombinant retroviral expressing vector MSCV-IRES-GFPat. The MSCV-IRES-GFPat was cotransfected into 293T cells with pCMV-VSV-G and pUMVC vectors to assemble the recombinant retrovirus. After infection of gliomas U87 cells with equal amount of the recombinant retrovirus, TNF-α, and IL-1β concentrations in the supernatant of U87 cells were determined with ELISA. Results HIV-1 tat genes derived from peripheral spleen and central basal ganglia of the AIDS patient with ADC and the other one without ADC exhibited genetic variations. Tat variations and amino acid mutation sites existed mainly at Tat protein core functional area (38-47aa). All Tat proteins could induce ug7 cells to produce TNF-α and IL-1β, but the level of IL-1β production was different among Tat proteins derived from the ADC patient's spleen, basal ganglia, and the non-ADC patient's spleen. The level of Tat proteins derived from the ADC patient's spleen, basal ganglia, and the non-ADC patient's spleen were obviously higher than that from the non-ADC patient's basal ganglia. Conclusion Tat protein core functional area (38-47aa) may serve as the key area of enhancing the secretion of IL-1β. This may be related with the neurotoxicity of HIV-1 Tat.展开更多
基金This research was partly supported by the Czech Science Foundation(No.GA19-05872S)。
摘要This study deals with constant-gain adaptive observers for nonlinear systems,for which relatively few solutions are available for some particular cases.We introduce an asymptotic observer of constant gain for nonlinear systems that have linear input.This allows the observer design to be formulated within the linear matrix inequality paradigm provided that a strictly positive real condition bet ween the inpu t disturbance and the output is fulfilled.The proposed observer is t hen applied to a large class of nonlinear chemos tat dynamical systems that are widely used in the fermentation process,cell cultures,medicine,etc.In fact,under standard practical assumptions,the necessary change of the chemos tat state coordinates exis ts,allowing use of the const ant-gain observer.Finally,the developed theory is illustrated by estimating pollutant concentration in a Spirulina maxima wastewater treatment facility.
基金supported by the National Natural Science Foundation of China(82272030,82472028,22277090)the construction project of Shanghai Key Laboratory of Molecular Imaging(18DZ2260400)+1 种基金the Natural Science Foundation of Shanghai(23ZR1466700)the Natural Science Foundation of Shandong Province(ZR2025QC1386).
摘要Background:Targeted alpha therapy(TAT)has emerged as a promising strategy for cancer treatment by selectively delivering high linear energy transfer(LET)alpha-emitters to tumor cells while minimizing off-target toxicity.However,the clinical translation of alpha-emitters,particularly radium-223(223Ra),remains challenging due to inefficient targeted delivery and uncontrolled release of recoil daughter products,leading to systemic toxicity.Methods:Herein,a dual-locked pretargeted strategy was developed integrating platinumⅣ(PtⅣ)-loaded hydrogel nanoparticles(HNPs)(HAQ@HNPs)and223Ra-loaded HNPs(223Ra@HNPs)into an inverse electron demand Diels-Alder(IEDDA)-activated drug delivery system.In vitro cytotoxicity,ROS,and apoptosis,together with in vivo biodistribution,imaging,and therapeutic studies,were performed to evaluate the therapeutic efficacy and immune activation.Results:This caged dual-locked approach enables precise pretargeted accumulation at the tumor site,followed by rapid dissociation and controlled release of223Ra and PtⅣupon IEDDA-triggered activation,thereby ensuring high tumor specificity while minimizing systemic exposure.The synergistic combination of TAT and chemotherapy effectively disrupts redox homeostasis,induces immunogenic cell death(ICD),and elicits a robust antitumor immune response.Furthermore,when combined with programmed death-ligand 1(PD-L1)blockade,this strategy significantly enhances systemic antitumor immunity,leading to robust inhibition of tumor growth and metastasis.Conclusions:These findings underscore the potential of dual-locked pretargeted strategies to advance TAT by improving therapeutic efficacy and addressing the critical challenge of radionuclide leakage,paving the way for next-generation precision-targeted radiopharmaceuticals.
摘要Objective To analyze the impact of depletion of the twin arginine translocation (TAT) system on virulence and physiology of Yersinia enterocolitica for a better understanding of its pathogenicity. Methods We constructed a △tatC::Sp^R mutant of Yersinia enterocolitica by P1 phage mediated transduction using Escherichia coli K-12 △tatC::Sp^R strain as a donor. Results A Pl-mediated genetic material transfer was found between the two species of enterobacteria, indicating a great potential of acquisition of antibiotic resistance in emergency of a new threatening pathogen by genetic material exchanges. Periplasmic trimethylamine N-oxidase reductase activity was detected in the wild type E enterocolitica strain and translocation of this enzyme was completely abolished by the △tatC::Sp^R mutation. In addition, the △tatC::Sp^R mutation showed a pleiotropic effect on the metabolism of E enterocolitica. However, the tat mutation did not seem to affect the mobility and virulence of Y. enterocolitica under the conditions used. Conclusion Unlike other pathogenic bacteria studied, the TAT system of E enterocolitica might play an important role in the pathogenic process, which is distinct from other pathogens, such as Pseudomonas aeruginosa and enterohemorrhagic E. coli O 157:H7.
摘要【目的】研究过表达枯草芽孢杆菌Tat运输途径的Tat Ad Cd转位酶对促进脂肪酶分泌的影响。【方法】用cdd基因的串联启动子和前导区,替换tat AD-CD操纵子的启动子和前导区,并在染色体sac B基因位点整合表达;采用q RT-PCR方法表征tat AD-CD操纵子的表达水平;用脂肪酶表达质粒p HP13L转化Tat Ad Cd转位酶过表达菌株,构建产脂肪酶重组菌。通过测定脂肪酶活性,以及聚丙烯酰胺凝胶电泳,考察Tat Ad Cd转位酶过表达对脂肪酶分泌的影响。【结果】tat AD-CD操纵子被过表达,其胞内m RNA相对水平提高了185倍。Tat Ad Cd转位酶的过表达,使脂肪酶发酵单位提高了40%。【结论】使用cdd基因的串联启动子和前导区,能够有效地过表达目的基因;枯草芽孢杆菌脂肪酶可以同时经由Sec途径和Tat途径分泌;过表达Tat Ad Cd转位酶,能够显著提高脂肪酶的分泌量。
基金supported by the Science&Technology Development Program of Shandong Province(Grant No.2007GG30002003)
摘要Objective To explore the role of HIV-1 tat gene variations in AIDS dementia complex (ADC) pathogenesis. Methods HIV-1 tat genes derived from peripheral spleen and central basal ganglia of an AIDS patient with ADC and an AIDS patient without ADC were cloned for sequence analysis. HIV-1 tat gene sequence alignment was performed by using CLUSTAL W and the phylogentic analysis was conducted by using Neighbor-joining with MEGA4 software. All tat genes were used to construct recombinant retroviral expressing vector MSCV-IRES-GFPat. The MSCV-IRES-GFPat was cotransfected into 293T cells with pCMV-VSV-G and pUMVC vectors to assemble the recombinant retrovirus. After infection of gliomas U87 cells with equal amount of the recombinant retrovirus, TNF-α, and IL-1β concentrations in the supernatant of U87 cells were determined with ELISA. Results HIV-1 tat genes derived from peripheral spleen and central basal ganglia of the AIDS patient with ADC and the other one without ADC exhibited genetic variations. Tat variations and amino acid mutation sites existed mainly at Tat protein core functional area (38-47aa). All Tat proteins could induce ug7 cells to produce TNF-α and IL-1β, but the level of IL-1β production was different among Tat proteins derived from the ADC patient's spleen, basal ganglia, and the non-ADC patient's spleen. The level of Tat proteins derived from the ADC patient's spleen, basal ganglia, and the non-ADC patient's spleen were obviously higher than that from the non-ADC patient's basal ganglia. Conclusion Tat protein core functional area (38-47aa) may serve as the key area of enhancing the secretion of IL-1β. This may be related with the neurotoxicity of HIV-1 Tat.