Background Comeal neovascular leakage can lead to edema and secondary scarring. Previous studies have shown that pericytes play a key role in maturation of angiogenesis. The present studies investigate the relationshi...Background Comeal neovascular leakage can lead to edema and secondary scarring. Previous studies have shown that pericytes play a key role in maturation of angiogenesis. The present studies investigate the relationship between vascular permeability and pericyte coverage of endothelial cells in rat corneal neovascular induced by alkali bums. Methods Corneal neovascular vessels induced by alkali bums was performed in Sprague-Dawley rats. Corneas were excised on 1,2, 3, 5, 7 and 10 days after cauterization. The vascular permeability rate was measured by the Evans blue method. The microvessel pericyte coverage index (MPI) was applied to quantify the pericyte coverage through double immunofluorescent staining of frozen sections of corneas with CD31 as the endothelial and α-smooth muscle actin (α-SMA) as the pericyte markers. The correlation between permeability rate and MPI was analyzed. Pericyte coverage was confirmed ultrastructually using transmission electron microscopy. Results The vascular permeability rate was (1.14±0.17), (0.24±0.08), (0.29±0.16), (0.14±0.10), (0.09±0.06) and (0.05±0.04)μg· ml^-1 · mm^-2respectively on 1, 2, 3, 5, 7 and 10 days after cauterization. The MPI was 0, 16.07%, 11.95%, 43.84%, 73.97% and 86.21% respectively at the above mentioned time points. The correlation coefficient between MPI and the permeability rate was -0.943 (P=-0.005). Conclusions Pericyte recruitment was significantly correlated with the permeability of comeal neovascularization induced by alkali bums in rats. Therapeutic strategies aiming at anti-leakage should be most effective if they promote pericytes proliferation in the course of corneal neovascularization.展开更多
Nitrogen doped fluorinated amorphous carbon thin films(a-C:N:F)were prepared by radio frequency plasma enhanced chemical vapor deposition(rf-PECVD)under different deposited condition usingCH_4,CF_4,and N_2 as source g...Nitrogen doped fluorinated amorphous carbon thin films(a-C:N:F)were prepared by radio frequency plasma enhanced chemical vapor deposition(rf-PECVD)under different deposited condition usingCH_4,CF_4,and N_2 as source gases.The thin films were annealed at different temperature.The influence of doped nitrogen on the chemical structure, tribological and thermal properties of thin films were investigated by Atomic force microscopy(AFM),Fourier transform infrared absorption spectrometry(FTIR),X-ray photoelectron spectrum spectra(XPS),and thermogravimetry(TG).The results indicated that the thin films presence a compact and smooth morphology surface after the nitrogen doped.After incorporation of nitrogen,the H atoms are replaced partially by the N atoms in the thin films.The degree of cross-linking of the carbon network in the thin films is enhanced.The chemical bonds of C=N,C≡N,and C—N_x(x=1,2,3) have formed in the films.The relative content of sp^2 graphite phase increases.The thermal stability temperature of the films deposited at r=0.5(r=N_2/[CF_4+CH_4+N_2])is 420℃.The tribological properties improve greatly,and the friction coefficient of the a-C:N:F thin films ranges approximately from 0.20 to 0.36.展开更多
基金National Science Fund for Distinguished Young Scholars(No.30225044)Fund for Innovative Research Groups of China (No. 30321004)Natural Science Foundation of Guangdong Province of China (No. 36652).
文摘Background Comeal neovascular leakage can lead to edema and secondary scarring. Previous studies have shown that pericytes play a key role in maturation of angiogenesis. The present studies investigate the relationship between vascular permeability and pericyte coverage of endothelial cells in rat corneal neovascular induced by alkali bums. Methods Corneal neovascular vessels induced by alkali bums was performed in Sprague-Dawley rats. Corneas were excised on 1,2, 3, 5, 7 and 10 days after cauterization. The vascular permeability rate was measured by the Evans blue method. The microvessel pericyte coverage index (MPI) was applied to quantify the pericyte coverage through double immunofluorescent staining of frozen sections of corneas with CD31 as the endothelial and α-smooth muscle actin (α-SMA) as the pericyte markers. The correlation between permeability rate and MPI was analyzed. Pericyte coverage was confirmed ultrastructually using transmission electron microscopy. Results The vascular permeability rate was (1.14±0.17), (0.24±0.08), (0.29±0.16), (0.14±0.10), (0.09±0.06) and (0.05±0.04)μg· ml^-1 · mm^-2respectively on 1, 2, 3, 5, 7 and 10 days after cauterization. The MPI was 0, 16.07%, 11.95%, 43.84%, 73.97% and 86.21% respectively at the above mentioned time points. The correlation coefficient between MPI and the permeability rate was -0.943 (P=-0.005). Conclusions Pericyte recruitment was significantly correlated with the permeability of comeal neovascularization induced by alkali bums in rats. Therapeutic strategies aiming at anti-leakage should be most effective if they promote pericytes proliferation in the course of corneal neovascularization.
基金Item Sponsored by National Natural Science Foundation of China[No.11064003]
文摘Nitrogen doped fluorinated amorphous carbon thin films(a-C:N:F)were prepared by radio frequency plasma enhanced chemical vapor deposition(rf-PECVD)under different deposited condition usingCH_4,CF_4,and N_2 as source gases.The thin films were annealed at different temperature.The influence of doped nitrogen on the chemical structure, tribological and thermal properties of thin films were investigated by Atomic force microscopy(AFM),Fourier transform infrared absorption spectrometry(FTIR),X-ray photoelectron spectrum spectra(XPS),and thermogravimetry(TG).The results indicated that the thin films presence a compact and smooth morphology surface after the nitrogen doped.After incorporation of nitrogen,the H atoms are replaced partially by the N atoms in the thin films.The degree of cross-linking of the carbon network in the thin films is enhanced.The chemical bonds of C=N,C≡N,and C—N_x(x=1,2,3) have formed in the films.The relative content of sp^2 graphite phase increases.The thermal stability temperature of the films deposited at r=0.5(r=N_2/[CF_4+CH_4+N_2])is 420℃.The tribological properties improve greatly,and the friction coefficient of the a-C:N:F thin films ranges approximately from 0.20 to 0.36.