Mesenchymal stem cells(MSC)have been used in clinical trials for severe diabetes,a chronic disease with high morbidity and mortality.Bone marrow is the traditional source of human MSC,but human term placenta appears t...Mesenchymal stem cells(MSC)have been used in clinical trials for severe diabetes,a chronic disease with high morbidity and mortality.Bone marrow is the traditional source of human MSC,but human term placenta appears to be an alternative and more readily available source.Here,the therapeutic effect of human placenta-derived MSC(PD-MSC)was studied in type 2 diabetes patients with longer duration,islet cell dysfunction,high insulin doses as well as poor glycemic control in order to evaluate the safety,efficacy and feasibility of PD-MSC treatment in type 2 diabetes(T2D).Ten patients with T2D received three intravenous infusions of PDSC,with one month interval of infusion.The total number of PDSC for each patient was(1.22–1.51)×10^(6)/kg,with an average of 1.35×10^(6)/kg.All of the patients were followed up after therapy for at least 3 months.A daily mean dose of insulin used in 10 patients was decreased from 63.7±18.7 to 34.7±13.4 IU(P<0.01),and the C-peptide level was increased from 4.1±3.7 ng/mL to 5.6±3.8 ng/mL(P<0.05)respectively after therapy.In 4 of 10 responders their insulin doses reduced more than 50%after infusion.The mean levels of insulin and C-peptide at each time point in a total of 10 patients was higher after treatment(P<0.05).No fever,chills,liver damage and other side effects were reported.The renal function and cardiac function were improved after infusion.The results obtained from this pilot clinical trial indicate that transplantation of PD-MSC represents a simple,safe and effective therapeutic approach for T2D patients with islet cell dysfunction.Further large-scale,randomized and well-controlled clinical studies will be required to substantiate these observations.展开更多
A knowledge of the adsorption and desorption behavior of sorbates on surface adsorptive site(SAS)is the key to optimizing the chemical reactivity of catalysts.However,direct identification of the chemical reactivity o...A knowledge of the adsorption and desorption behavior of sorbates on surface adsorptive site(SAS)is the key to optimizing the chemical reactivity of catalysts.However,direct identification of the chemical reactivity of SASs is still a challenge due to the limitations of characterization techniques.Here,we present a new pathway to determine the kinetics of adsorption/desorption on SASs of graphene oxide(GO)based on total internal reflectance fluorescence microscopy.The switching on and off of the fluorescent signal of SAS lit by carbon dots(CDs)was used to trace the adsorption process and desorption process.We find that sodium pyrophosphate(PPi)could increase the adsorption equilibrium of CDs thermodynamically and promote the substrate-assisted desorption pathway kinetically.At the single turnover level,it was disclosed that the species that can promote desorption may also be an adsorption promoter.Such discovery provides significant guidance for improving the chemical reactivity of the heterogeneous catalyst.展开更多
文摘Mesenchymal stem cells(MSC)have been used in clinical trials for severe diabetes,a chronic disease with high morbidity and mortality.Bone marrow is the traditional source of human MSC,but human term placenta appears to be an alternative and more readily available source.Here,the therapeutic effect of human placenta-derived MSC(PD-MSC)was studied in type 2 diabetes patients with longer duration,islet cell dysfunction,high insulin doses as well as poor glycemic control in order to evaluate the safety,efficacy and feasibility of PD-MSC treatment in type 2 diabetes(T2D).Ten patients with T2D received three intravenous infusions of PDSC,with one month interval of infusion.The total number of PDSC for each patient was(1.22–1.51)×10^(6)/kg,with an average of 1.35×10^(6)/kg.All of the patients were followed up after therapy for at least 3 months.A daily mean dose of insulin used in 10 patients was decreased from 63.7±18.7 to 34.7±13.4 IU(P<0.01),and the C-peptide level was increased from 4.1±3.7 ng/mL to 5.6±3.8 ng/mL(P<0.05)respectively after therapy.In 4 of 10 responders their insulin doses reduced more than 50%after infusion.The mean levels of insulin and C-peptide at each time point in a total of 10 patients was higher after treatment(P<0.05).No fever,chills,liver damage and other side effects were reported.The renal function and cardiac function were improved after infusion.The results obtained from this pilot clinical trial indicate that transplantation of PD-MSC represents a simple,safe and effective therapeutic approach for T2D patients with islet cell dysfunction.Further large-scale,randomized and well-controlled clinical studies will be required to substantiate these observations.
基金This work was funded by the Research&Development Projects in Key Areas of Guangdong Province,China(2019B010933001)the National Natural Science Foundation of China(21974033,21904026)+1 种基金the National Basic Research Program of China(973 Program,2017YFE0197900)the Innovation Training Program for College Students of Guangzhou University(CX2019185).
文摘A knowledge of the adsorption and desorption behavior of sorbates on surface adsorptive site(SAS)is the key to optimizing the chemical reactivity of catalysts.However,direct identification of the chemical reactivity of SASs is still a challenge due to the limitations of characterization techniques.Here,we present a new pathway to determine the kinetics of adsorption/desorption on SASs of graphene oxide(GO)based on total internal reflectance fluorescence microscopy.The switching on and off of the fluorescent signal of SAS lit by carbon dots(CDs)was used to trace the adsorption process and desorption process.We find that sodium pyrophosphate(PPi)could increase the adsorption equilibrium of CDs thermodynamically and promote the substrate-assisted desorption pathway kinetically.At the single turnover level,it was disclosed that the species that can promote desorption may also be an adsorption promoter.Such discovery provides significant guidance for improving the chemical reactivity of the heterogeneous catalyst.