BACKGROUND Bone marrow-derived mesenchymal stem cells(MSCs)show podocyte-protective effects in chronic kidney disease.Calycosin(CA),a phytoestrogen,is isolated from Astragalus membranaceus with a kidney-tonifying effe...BACKGROUND Bone marrow-derived mesenchymal stem cells(MSCs)show podocyte-protective effects in chronic kidney disease.Calycosin(CA),a phytoestrogen,is isolated from Astragalus membranaceus with a kidney-tonifying effect.CA preconditioning enhances the protective effect of MSCs against renal fibrosis in mice with unilateral ureteral occlusion.However,the protective effect and underlying mechanism of CA-pretreated MSCs(MSCsCA)on podocytes in adriamycin(ADR)-induced focal segmental glomerulosclerosis(FSGS)mice remain unclear.AIM To investigate whether CA enhances the role of MSCs in protecting against podocyte injury induced by ADR and the possible mechanism involved.METHODS ADR was used to induce FSGS in mice,and MSCs,CA,or MSCsCA were administered to mice.Their protective effect and possible mechanism of action on podocytes were observed by Western blot,immunohistochemistry,immunofluorescence,and real-time polymerase chain reaction.In vitro,ADR was used to stimulate mouse podocytes(MPC5)to induce injury,and the supernatants from MSC-,CA-,or MSCsCA-treated cells were collected to observe their protective effects on podocytes.Subsequently,the apoptosis of podocytes was detected in vivo and in vitro by Western blot,TUNEL assay,and immunofluorescence.Overexpression of Smad3,which is involved in apoptosis,was then induced to evaluate whether the MSCsCA-mediated podocyte protective effect is associated with Smad3 inhibition in MPC5 cells.RESULTS CA-pretreated MSCs enhanced the protective effect of MSCs against podocyte injury and the ability to inhibit podocyte apoptosis in ADR-induced FSGS mice and MPC5 cells.Expression of p-Smad3 was upregulated in mice with ADR-induced FSGS and MPC5 cells,which was reversed by MSCCA treatment more significantly than by MSCs or CA alone.When Smad3 was overexpressed in MPC5 cells,MSCsCA could not fulfill their potential to inhibit podocyte apoptosis.CONCLUSION MSCsCA enhance the protection of MSCs against ADR-induced podocyte apoptosis.The underlying mechanism may be related to MSCsCA-targeted inhibition of p-Smad3 in podocytes.展开更多
Automated segmentation and tracking of cells in actively developing tissues can provide high-throughput and quantitative spatiotemporal measurements of a range of cell behaviors; cell expansion and cell-division kinet...Automated segmentation and tracking of cells in actively developing tissues can provide high-throughput and quantitative spatiotemporal measurements of a range of cell behaviors; cell expansion and cell-division kinetics leading to a better understanding of the underlying dynamics of morphogenesis. Here, we have studied the problem of constructing cell lineages in time-lapse volumetric image stacks obtained using Confocal Laser Scanning Microscopy （CLSM）. The novel contribution of the work lies in its ability to segment and track cells in densely packed tissue, the shoot apical meristem （SAM）, through the use of a close-loop, adaptive segmentation, and tracking approach. The tracking output acts as an indicator of the quality of segmentation and, in turn, the segmentation can be improved to obtain better tracking results. We construct an optimization function that minimizes the segmentation error, which is, in turn, estimated from the tracking results. This adaptive approach significantly improves both tracking and segmentation when compared to an open loop framework in which segmentation and tracking modules operate separately.展开更多
Backgrounds Time-lapse live cell imaging of a growing cell population is routine in many biological investigations.A major challenge in imaging analysis is accurate segmentation,a process to define the boundaries of c...Backgrounds Time-lapse live cell imaging of a growing cell population is routine in many biological investigations.A major challenge in imaging analysis is accurate segmentation,a process to define the boundaries of cells based on raw image data.Current segmentation methods relying on single boundary features have problems in robustness when dealing with inhomogeneous foci which invariably happens in cell population imaging.Methods:Combined with a multi-layer training set strategy,we developed a neural-network-based algorithm—Cellbow.Results'Cellbow can achieve accurate and robust segmentation of cells in broad and general settings.It can also facilitate long-term tracking of cell growth and division.To facilitate the application of Cellbow,we provide a website on which one can online test the software,as well as an I mage J plugin for the user to visualize the performance before software installation.Conclusions Cellbow is customizable and generalizable.It is broadly applicable to segmenting fluorescent images of diverse cell types with no further training needed.For bright-field images,only a small set of sample images of the specific cell type from the user may be needed for training.展开更多
In order to obtain larger,clinical-scale and practical-scale bone grafts,we have designed both tailored scaffolds and tailored bio incubator with optimal bio-production characteristics.Using DIC files to Simpleware Sc...In order to obtain larger,clinical-scale and practical-scale bone grafts,we have designed both tailored scaffolds and tailored bio incubator with optimal bio-production characteristics.Using DIC files to Simpleware Scan-IP(Simple-ware-exeter United Kingdom),we have digitally reconstructed segmental additive bone-tissue in order to perform images processing.Both hydroxyapatite and tannin composites have been used in order to get the final bone modules combined for retexturing of segmental bone defect.We have found that sectioning of bone segment deficiency reorganizations into well disk-shaped design permits one to standardize the cell culture and seeding protocol,to get better products.The present study concludes that some techniques with cultured cell in segmental bone grafts in the laboratory can be transferred and clinically used.展开更多
基金the National Natural Science Foundation of China(General Program),No.82205002Science and Technology Project of Sichuan Province,No.2022YFS0621,No.21ZDYF0348,and No.2022NSFSC1459+1 种基金Luzhou-Southwest Medical University Science and Technology Strategic Cooperation Project,No.2021LZXNYD-P04Southwest Medical University of Affiliated Traditional Medicine Hospital Project,No.2022-CXTD-03.
文摘BACKGROUND Bone marrow-derived mesenchymal stem cells(MSCs)show podocyte-protective effects in chronic kidney disease.Calycosin(CA),a phytoestrogen,is isolated from Astragalus membranaceus with a kidney-tonifying effect.CA preconditioning enhances the protective effect of MSCs against renal fibrosis in mice with unilateral ureteral occlusion.However,the protective effect and underlying mechanism of CA-pretreated MSCs(MSCsCA)on podocytes in adriamycin(ADR)-induced focal segmental glomerulosclerosis(FSGS)mice remain unclear.AIM To investigate whether CA enhances the role of MSCs in protecting against podocyte injury induced by ADR and the possible mechanism involved.METHODS ADR was used to induce FSGS in mice,and MSCs,CA,or MSCsCA were administered to mice.Their protective effect and possible mechanism of action on podocytes were observed by Western blot,immunohistochemistry,immunofluorescence,and real-time polymerase chain reaction.In vitro,ADR was used to stimulate mouse podocytes(MPC5)to induce injury,and the supernatants from MSC-,CA-,or MSCsCA-treated cells were collected to observe their protective effects on podocytes.Subsequently,the apoptosis of podocytes was detected in vivo and in vitro by Western blot,TUNEL assay,and immunofluorescence.Overexpression of Smad3,which is involved in apoptosis,was then induced to evaluate whether the MSCsCA-mediated podocyte protective effect is associated with Smad3 inhibition in MPC5 cells.RESULTS CA-pretreated MSCs enhanced the protective effect of MSCs against podocyte injury and the ability to inhibit podocyte apoptosis in ADR-induced FSGS mice and MPC5 cells.Expression of p-Smad3 was upregulated in mice with ADR-induced FSGS and MPC5 cells,which was reversed by MSCCA treatment more significantly than by MSCs or CA alone.When Smad3 was overexpressed in MPC5 cells,MSCsCA could not fulfill their potential to inhibit podocyte apoptosis.CONCLUSION MSCsCA enhance the protection of MSCs against ADR-induced podocyte apoptosis.The underlying mechanism may be related to MSCsCA-targeted inhibition of p-Smad3 in podocytes.
文摘Automated segmentation and tracking of cells in actively developing tissues can provide high-throughput and quantitative spatiotemporal measurements of a range of cell behaviors; cell expansion and cell-division kinetics leading to a better understanding of the underlying dynamics of morphogenesis. Here, we have studied the problem of constructing cell lineages in time-lapse volumetric image stacks obtained using Confocal Laser Scanning Microscopy （CLSM）. The novel contribution of the work lies in its ability to segment and track cells in densely packed tissue, the shoot apical meristem （SAM）, through the use of a close-loop, adaptive segmentation, and tracking approach. The tracking output acts as an indicator of the quality of segmentation and, in turn, the segmentation can be improved to obtain better tracking results. We construct an optimization function that minimizes the segmentation error, which is, in turn, estimated from the tracking results. This adaptive approach significantly improves both tracking and segmentation when compared to an open loop framework in which segmentation and tracking modules operate separately.
基金This work was supported by the Ministry of Science and Technology of China(2015CB910300)the National Key Research and Development Program of China(2018YFA0900700)the National Natural Science Foundation of China(NSFC31700733).Part of the analysis was performed on the High Performance Computing Platform of the Center for Life Science.
文摘Backgrounds Time-lapse live cell imaging of a growing cell population is routine in many biological investigations.A major challenge in imaging analysis is accurate segmentation,a process to define the boundaries of cells based on raw image data.Current segmentation methods relying on single boundary features have problems in robustness when dealing with inhomogeneous foci which invariably happens in cell population imaging.Methods:Combined with a multi-layer training set strategy,we developed a neural-network-based algorithm—Cellbow.Results'Cellbow can achieve accurate and robust segmentation of cells in broad and general settings.It can also facilitate long-term tracking of cell growth and division.To facilitate the application of Cellbow,we provide a website on which one can online test the software,as well as an I mage J plugin for the user to visualize the performance before software installation.Conclusions Cellbow is customizable and generalizable.It is broadly applicable to segmenting fluorescent images of diverse cell types with no further training needed.For bright-field images,only a small set of sample images of the specific cell type from the user may be needed for training.
文摘In order to obtain larger,clinical-scale and practical-scale bone grafts,we have designed both tailored scaffolds and tailored bio incubator with optimal bio-production characteristics.Using DIC files to Simpleware Scan-IP(Simple-ware-exeter United Kingdom),we have digitally reconstructed segmental additive bone-tissue in order to perform images processing.Both hydroxyapatite and tannin composites have been used in order to get the final bone modules combined for retexturing of segmental bone defect.We have found that sectioning of bone segment deficiency reorganizations into well disk-shaped design permits one to standardize the cell culture and seeding protocol,to get better products.The present study concludes that some techniques with cultured cell in segmental bone grafts in the laboratory can be transferred and clinically used.
