Stem cell therapy is a promising strategy for the treatment of traumatic brain injury(TBI). However, animal experiments are needed to evaluate safety;in particular, to examine the immunogenicity and tumorigenicity of ...Stem cell therapy is a promising strategy for the treatment of traumatic brain injury(TBI). However, animal experiments are needed to evaluate safety;in particular, to examine the immunogenicity and tumorigenicity of human umbilical cord mesenchymal stem cells(hu MSCs) before clinical application. In this study, hu MSCs were harvested from human amniotic membrane and umbilical cord vascular tissue. A rat model of TBI was established using the controlled cortical impact method. Starting from the third day after injury, the rats were injected with 10 μL of 5 × 10^(6)/m L hu MSCs by cerebral stereotaxis or with 500 μL of 1 × 10^(6)/m L hu MSCs via the tail vein for 3 successive days. hu MSC transplantation decreased the serum levels of proinflammatory cytokines in rats with TBI and increased the serum levels of anti-inflammatory cytokines, thereby exhibiting good immunoregulatory function. The transplanted hu MSCs were distributed in the liver, lung and brain injury sites. No abnormal proliferation or tumorigenesis was found in these organs up to 12 months after transplantation. The transplanted hu MSCs negligibly proliferated in vivo, and apoptosis was gradually observed at later stages. These findings suggest that hu MSC transplantation for the treatment of traumatic brain injury displays good safety. In addition, hu MSCs exhibit good immunoregulatory function, which can help prevent and reduce secondary brain injury caused by the rapid release of inflammatory factors after TBI. This study was approved by the Ethics Committee of Wuhan General Hospital of PLA(approval No. 20160054) on November 1, 2016.展开更多
Acanthopanax senticosus aqueous extract, at 10, 5 and 2.5 μg/mL, lessened hypoxia-induced PC12 cell injury. Pretreatment with the extract upregulated Bcl-2 expression, downregulated Bax expression, elevated superoxid...Acanthopanax senticosus aqueous extract, at 10, 5 and 2.5 μg/mL, lessened hypoxia-induced PC12 cell injury. Pretreatment with the extract upregulated Bcl-2 expression, downregulated Bax expression, elevated superoxide dismutase activity, diminished malondialdehyde content, relieved Ca2＋ overloading, and suppressed apoptosis of PC12 cells. These effects were most pronounced at 10 μg/mL. These results suggest that Acanthopanax senticosus aqueous extract protects PC12 cells from hypoxia-induced injury in a dose-dependent manner.展开更多
Detection of antibodies against severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)is a supplemental option for reverse transcription polymerase chain reaction(RT-PCR)detection,regardless of whether it is immu...Detection of antibodies against severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)is a supplemental option for reverse transcription polymerase chain reaction(RT-PCR)detection,regardless of whether it is immunoglobulin M(IgM),immunoglobulin G(IgG)or combined detection.However,there are inadequate data on the sensitivity and specificity of IgM/IgG detection,which is of paramount importance for the decision of whether,when,and how to use IgM/IgG antibody detection.The aim of this study was to evaluate the sensitivity,specificity,accuracy,positive predictive value(PPV),and negative predictive value(NPV)of IgM/IgG antibody detection,especially the anti-interference ability and kappa coefficient compared with the SARS-CoV-2 RT-PCR,which was defined as a standard diagnosis in this study.展开更多
To overcome the problem that steel bars are put too close at a flame joint with special-shaped beam and column,mechanical performance of three groups of six RC flame joints with special-shaped(L,T and+)column and disp...To overcome the problem that steel bars are put too close at a flame joint with special-shaped beam and column,mechanical performance of three groups of six RC flame joints with special-shaped(L,T and+)column and dispersed-steel bars-beam on the top floor under cyclic loads were studied.Experimental comparison was conducted between special-shaped(L,T and+)column and normal beams.The cracking load,yielding load,ultimate bearing capacity,failure patterns,and hysteretic properties at joint core area were investigated.The seismic behaviors of the joints with different proportions of dispersed-steelbar beams were analyzed.The results of experimental analysis indicate that the mechanical and seismic behaviors of frame joints with T-shaped and+-shaped column are nearly not changed when suitable proportion steel bars are dispersed to flange plane.Stiffness degeneration of flame joint with L-shaped column is rather serious due to concrete damage stiffness.Theoretical result indicates that distributing area of the dispersed steel-bar beams in the flange plate should be strictly controlled to avoid anchor destroy.展开更多
基金supported by the General Project of Hubei Health Committee of China,No.WJ2019M263(to GW)。
文摘Stem cell therapy is a promising strategy for the treatment of traumatic brain injury(TBI). However, animal experiments are needed to evaluate safety;in particular, to examine the immunogenicity and tumorigenicity of human umbilical cord mesenchymal stem cells(hu MSCs) before clinical application. In this study, hu MSCs were harvested from human amniotic membrane and umbilical cord vascular tissue. A rat model of TBI was established using the controlled cortical impact method. Starting from the third day after injury, the rats were injected with 10 μL of 5 × 10^(6)/m L hu MSCs by cerebral stereotaxis or with 500 μL of 1 × 10^(6)/m L hu MSCs via the tail vein for 3 successive days. hu MSC transplantation decreased the serum levels of proinflammatory cytokines in rats with TBI and increased the serum levels of anti-inflammatory cytokines, thereby exhibiting good immunoregulatory function. The transplanted hu MSCs were distributed in the liver, lung and brain injury sites. No abnormal proliferation or tumorigenesis was found in these organs up to 12 months after transplantation. The transplanted hu MSCs negligibly proliferated in vivo, and apoptosis was gradually observed at later stages. These findings suggest that hu MSC transplantation for the treatment of traumatic brain injury displays good safety. In addition, hu MSCs exhibit good immunoregulatory function, which can help prevent and reduce secondary brain injury caused by the rapid release of inflammatory factors after TBI. This study was approved by the Ethics Committee of Wuhan General Hospital of PLA(approval No. 20160054) on November 1, 2016.
基金a grant from the Young Foundation of Wuhan General Hospital of Guangzhou Military Command of Chinese PLA, No. 200810
文摘Acanthopanax senticosus aqueous extract, at 10, 5 and 2.5 μg/mL, lessened hypoxia-induced PC12 cell injury. Pretreatment with the extract upregulated Bcl-2 expression, downregulated Bax expression, elevated superoxide dismutase activity, diminished malondialdehyde content, relieved Ca2＋ overloading, and suppressed apoptosis of PC12 cells. These effects were most pronounced at 10 μg/mL. These results suggest that Acanthopanax senticosus aqueous extract protects PC12 cells from hypoxia-induced injury in a dose-dependent manner.
文摘Detection of antibodies against severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)is a supplemental option for reverse transcription polymerase chain reaction(RT-PCR)detection,regardless of whether it is immunoglobulin M(IgM),immunoglobulin G(IgG)or combined detection.However,there are inadequate data on the sensitivity and specificity of IgM/IgG detection,which is of paramount importance for the decision of whether,when,and how to use IgM/IgG antibody detection.The aim of this study was to evaluate the sensitivity,specificity,accuracy,positive predictive value(PPV),and negative predictive value(NPV)of IgM/IgG antibody detection,especially the anti-interference ability and kappa coefficient compared with the SARS-CoV-2 RT-PCR,which was defined as a standard diagnosis in this study.
基金This work was partly financial supported by the National Natural Science Foundation of China(Grant No.50678016).
文摘To overcome the problem that steel bars are put too close at a flame joint with special-shaped beam and column,mechanical performance of three groups of six RC flame joints with special-shaped(L,T and+)column and dispersed-steel bars-beam on the top floor under cyclic loads were studied.Experimental comparison was conducted between special-shaped(L,T and+)column and normal beams.The cracking load,yielding load,ultimate bearing capacity,failure patterns,and hysteretic properties at joint core area were investigated.The seismic behaviors of the joints with different proportions of dispersed-steelbar beams were analyzed.The results of experimental analysis indicate that the mechanical and seismic behaviors of frame joints with T-shaped and+-shaped column are nearly not changed when suitable proportion steel bars are dispersed to flange plane.Stiffness degeneration of flame joint with L-shaped column is rather serious due to concrete damage stiffness.Theoretical result indicates that distributing area of the dispersed steel-bar beams in the flange plate should be strictly controlled to avoid anchor destroy.
