Background： Corneal stromal cells （CSCs） are components of the corneal endothelial microenvironment that can be induced to form a functional tissue-engineered corneal endothelium. Adipose-derived mesenchymal stem c...Background： Corneal stromal cells （CSCs） are components of the corneal endothelial microenvironment that can be induced to form a functional tissue-engineered corneal endothelium. Adipose-derived mesenchymal stem cells （ADSCs） have been reported as an important component of regenerative medicine and cell therapy for corneal stromal damage. We have demonstrated that the treatment with ADSCs leads to phenotypic changes in CSCs in vitro. However, the underlying mechanisms of such ADSC-induced changes in CSCs remain unclear. Methods： ADSCs and CSCs were isolated from New Zealand white rabbits and cultured in vitro. An Exosome Isolation Kit, Western blotting, and nanoparticle tracking analysis （NTA） were used to isolate and confirm the exosomes from ADSC culture medium. Meanwhile, the optimal exosome concentration and treatment time were selected. Cell Counting Kit-8 and annexin V-fluorescein isothiocyanate/ propidium iodide assays were used to assess the effect of ADSC-derived exosomes on the proliferation and apoptosis of CSCs. To evaluate the effects ofADSC-derived exosomes on CSC invasion activity, Western blotting was used to detect the expression of matrix metalloproteinases （MMPs） and collagens. Results： ADSCs and CSCs were successfully isolated from New Zealand rabbits. The optimal concentration and treatment time of exosomes for the following study were 100 μg/ml and 96 h, respectively. NTA revealed that the ADSC-derived exosomes appeared as nanoparticles （40-200 nm）, and Western blotting confirmed positive expression of CD9, CDSI, flotillin-1, and HSP70 versus ADSC cytoplasmic proteins （all P〈 0.01 ）. ADSC-derived exosomes （50μg/ml and 100μg/ml） significantly promoted proliferation and inhibited apoptosis （mainly early apoptosis） of CSCs versus non-exosome-treated CSCs （all P 〈 0.05）. Interestingly, MMPs were downregulated and extracellular matrix （ECM）-related proteins including collagens and fibronectin were upregulated in the exosome-treated CSCs versus non-exosome-treated CSCs （MMPI： t = 80.103, P 〈 0.01; MMP2： t = 114.778, P 〈 0.01; MMP3： t = 56.208, P 〈 0.01; and MMP9： t = 60.617, P〈 0.01; collagen I： t = -82.742, P〈 0.01; collagen II： t = -72.818, P〈 0.01; collagen III： t = -104.452, P〈 0.01; collagen IV： t = - 133.426, P 〈 0.01, and collagen V： t - -294.019, P 〈 0.01 ; and fibronectin： t = -92.491, P 〈 0.01, respectively）. Conclusion： The findings indicate that ADSCs might play an important role in CSC viability regulation and ECM remodeling, partially through the secretion of exosomes.展开更多
A four-point bending apparatus is used to investigate the effects of stretching on collagen synthesis, mineralization and differentiation of osteoblasts. Cells are stretched at 1500 με for 24 hours. The responses of...A four-point bending apparatus is used to investigate the effects of stretching on collagen synthesis, mineralization and differentiation of osteoblasts. Cells are stretched at 1500 με for 24 hours. The responses of osteoblasts to mechanical signal of physiological stretching are evaluated from three aspects: collagen production, extracellular inorganic calcium secretion and ALP activity. The results show that osteoblasts decrease the collagen synthesis, calcium secretion and ALP activity compared to the control cells (65.82%,73.51%,48.10% respectively), confirming that cyclic stretching at 1500 με inhabits the physiological activity of osteoblasts.展开更多
Two types of alumina dispersion-strengthened copper（ADSC） alloys were fabricated by a novel in-situ reactive synthesis（IRS） and a traditional internal oxidation（IO） process. The features of alumina dispersoids i...Two types of alumina dispersion-strengthened copper（ADSC） alloys were fabricated by a novel in-situ reactive synthesis（IRS） and a traditional internal oxidation（IO） process. The features of alumina dispersoids in these ADSC alloys were investigated by X-ray diffraction, scanning electron microscopy, and high-resolution transmission electron microscopy. It is found that nano-sized γ-Al2O3 particles of approximately 10 nm in diameter are homogeneously distributed in the IRS-ADSC composites. Meanwhile, larger-sized, mixed crystal structure alumina with rod-shaped morphology is embedded in the IO-ADSC alloy. The IRS-ADSC composites can obtain better mechanical and physical properties than the IO-ADSC composites; the tensile strength of the IRS-ADSC alloy can reach 570 MPa at room temperature, its electrical conductivity is 85% IACS, and the Rockwell hardness can reach 86 HRB.展开更多
基金This work was supported by grants from the National Natural Science Foundation of China （No. 81700795）, and the Natural Science Foundation of Zhejiang Province （No. LY13H120007）.
文摘Background： Corneal stromal cells （CSCs） are components of the corneal endothelial microenvironment that can be induced to form a functional tissue-engineered corneal endothelium. Adipose-derived mesenchymal stem cells （ADSCs） have been reported as an important component of regenerative medicine and cell therapy for corneal stromal damage. We have demonstrated that the treatment with ADSCs leads to phenotypic changes in CSCs in vitro. However, the underlying mechanisms of such ADSC-induced changes in CSCs remain unclear. Methods： ADSCs and CSCs were isolated from New Zealand white rabbits and cultured in vitro. An Exosome Isolation Kit, Western blotting, and nanoparticle tracking analysis （NTA） were used to isolate and confirm the exosomes from ADSC culture medium. Meanwhile, the optimal exosome concentration and treatment time were selected. Cell Counting Kit-8 and annexin V-fluorescein isothiocyanate/ propidium iodide assays were used to assess the effect of ADSC-derived exosomes on the proliferation and apoptosis of CSCs. To evaluate the effects ofADSC-derived exosomes on CSC invasion activity, Western blotting was used to detect the expression of matrix metalloproteinases （MMPs） and collagens. Results： ADSCs and CSCs were successfully isolated from New Zealand rabbits. The optimal concentration and treatment time of exosomes for the following study were 100 μg/ml and 96 h, respectively. NTA revealed that the ADSC-derived exosomes appeared as nanoparticles （40-200 nm）, and Western blotting confirmed positive expression of CD9, CDSI, flotillin-1, and HSP70 versus ADSC cytoplasmic proteins （all P〈 0.01 ）. ADSC-derived exosomes （50μg/ml and 100μg/ml） significantly promoted proliferation and inhibited apoptosis （mainly early apoptosis） of CSCs versus non-exosome-treated CSCs （all P 〈 0.05）. Interestingly, MMPs were downregulated and extracellular matrix （ECM）-related proteins including collagens and fibronectin were upregulated in the exosome-treated CSCs versus non-exosome-treated CSCs （MMPI： t = 80.103, P 〈 0.01; MMP2： t = 114.778, P 〈 0.01; MMP3： t = 56.208, P 〈 0.01; and MMP9： t = 60.617, P〈 0.01; collagen I： t = -82.742, P〈 0.01; collagen II： t = -72.818, P〈 0.01; collagen III： t = -104.452, P〈 0.01; collagen IV： t = - 133.426, P 〈 0.01, and collagen V： t - -294.019, P 〈 0.01 ; and fibronectin： t = -92.491, P 〈 0.01, respectively）. Conclusion： The findings indicate that ADSCs might play an important role in CSC viability regulation and ECM remodeling, partially through the secretion of exosomes.
文摘A four-point bending apparatus is used to investigate the effects of stretching on collagen synthesis, mineralization and differentiation of osteoblasts. Cells are stretched at 1500 με for 24 hours. The responses of osteoblasts to mechanical signal of physiological stretching are evaluated from three aspects: collagen production, extracellular inorganic calcium secretion and ALP activity. The results show that osteoblasts decrease the collagen synthesis, calcium secretion and ALP activity compared to the control cells (65.82%,73.51%,48.10% respectively), confirming that cyclic stretching at 1500 με inhabits the physiological activity of osteoblasts.
基金financially supported by the National Natural Science Foundation of China(NO.51464013)the Dr.Initialization Fund of Jiangxi University of Science and Technology(No.jxxjbs14013)
文摘Two types of alumina dispersion-strengthened copper（ADSC） alloys were fabricated by a novel in-situ reactive synthesis（IRS） and a traditional internal oxidation（IO） process. The features of alumina dispersoids in these ADSC alloys were investigated by X-ray diffraction, scanning electron microscopy, and high-resolution transmission electron microscopy. It is found that nano-sized γ-Al2O3 particles of approximately 10 nm in diameter are homogeneously distributed in the IRS-ADSC composites. Meanwhile, larger-sized, mixed crystal structure alumina with rod-shaped morphology is embedded in the IO-ADSC alloy. The IRS-ADSC composites can obtain better mechanical and physical properties than the IO-ADSC composites; the tensile strength of the IRS-ADSC alloy can reach 570 MPa at room temperature, its electrical conductivity is 85% IACS, and the Rockwell hardness can reach 86 HRB.
