BACKGROUND: After loss of teeth, the dynamic equilibrium between osteoblast and osteoclast in alveolar bone is destroyed because of systematic and local factors, and residual ridge resorption and atrophy occur irreversibly, which result in the loss of massive alveolar bone. Bone morphogenetic protein-7 (BMP-7) exerts an important effect in the development and traumatic repair of bone and tooth.OBJECTIVE: To investigate the effect of human recombinant bone morphogenetic protein-7 (rhBMP-7) on new bone formation of alveolar ridge and absorption of alveolar ridge.DESIGN: Control experiment.SETTING: Department of Orthodontics, Jinan Stomatological Hospital;Shangdong Academy of Medical Sciences.MATERIALS: This study was conducted at the Shangdong Academy of Medical Sciences from June 2003 to December 2004. Totally 28 New Zealand white rabbits, of either gender, weighing 2 kg, were used in this study.METHODS: Animal extracted wound models were created on the rabbits.The mandibular left and right central incisor of the rabbits were removed.Two carriers containing BMP7 complex (40 μg/each) were implanted into the mandibular right central incisor (experimental group), two empty carriers containing only phosphate buffer solution(PBS) (40 μg/each) were implanted into the mandibular left central incisor (control group). The animals were sacrificed at postoperative 2, 4, 8 and 12 weeks. The specimen from the operated regions were harvested and observed by scanning electron microscope, and calcium content and alkaline phosphatase (ALP) activity were also measured.MAIN OUTCOME MEASURES: ① Result of scanning electron microscope (SEM). ② ALP activity and calcium content.RESULTS: ① The bone wound healing was 4-6 weeks earlier in the experimental group than in the control group . ② The ALP activity was significantly higher in the experimental group than in the control group [week 2:(38.191±5.384, (19.821±2.084) μkat/g;week 4: (160.815±9.669), (126.709±1.634) μkat/g;week 8: (378.892±13.086),(225.212±1.884) μkat/g,P ＜ 0.01]. ③ The calcium was significantly higher in the experimental group than in the control group [week 2:(5.592±0.110), (0.913±0.064) mg/g;week 4: (8.654±0.177), ( 1.702±0.071 ) mg/g;week 8: (25.326±0.287), (5.980±0.145) mg/g,P ＜ 0.01]CONCLUSION: BMP-7, which is expressed in the prokaryocyte, possesses good role in augmenting alveolar ridge and promoting the healing of alveolar wound.

Objective To investigate the effect of tetrandrine (Tet) on experimental choroidal neovascularization and the effect of Tet on retinal structure and function. Methods Choroidal neovascularization was induced in 20 Brown Norway (BN) rats (40 eyes) by diode laser (wavelength: 810 nm; exposal time: 0.1 second; facular diameter:100 ?m; energy: 120 mW), and the rats were divided randomly into experimental and control group with 10 rats (20 eyes) in each group. In experimental group, 0.05 ml Tet with the concentration of 3.21 ?mol/L was injected intravitreously 0 and 3 days after laser photocoagulation; in the control group, the rats underwent an intravitreous injection with the same volume of sodium chloride solution. The incidence of CNV was evaluated by fundus fluorescein angiography (FFA) 14 days after laser photocoagulation. Five right eyes of another Five healthy BN rats underwent intravitreous injection with 0.05 ml Tet with the concentration of 3.21 ?mol/L, and an intravitreous injection with the same volume of sodium chloride solution was performed on the left eyes. Before injection, 1 hour, and 1 day after the first injection, and 1 hour, 1 day, 7 days, 14 days after the second injection the electroretinography (ERG) was performed on these 5 rats; 14 days after the second injection, the retinae were examined by light microscopy and transmission electron microscopy. Results The incidence of CNV was 23.26% in experimental group,which was obviously lower than that in the control group (63.33%) (P0.05). There were no structural changes of retinal tissues examined by light and electron microscopy. Conclusion Tet may inhibit choroidal neovascularization in rats; there isn′t any significant toxic effect of intravitreous injection with Tet on retina at the dosage of 3.21 ?mol/L.

OBJECTIVE To study the amounts of pulpal lipopolysaccharide (LPS) in acute and chronic pulpitis and to analyze the relation between the amounts of LPS in pulpitis and the clinical symptoms. METHODS The Limulus test was used to analyze the amounts of LPS in the root canal of pulpitis, under the condition of acute and chronic pulpitis. RESULTS The amounts of LPS in 23 cases of acute pulpitis were found significantly higher than that in 22 cases of chronic pulpitis, P

In order to investigate the effects of TGF-beta1 on the expression of MMP-2, -9 and TIMP-1 in human retinal pigment epithelial (RPE) cells, the third-sixth passage cultured RPE cells were treated with TGF-beta1 at different concentrations (0.01, 0.1, 1.0, 10 ng/mL), the expression of MMP-2, -9 and TIMP-1 mRNA was detected by semi-quantitative RT-PCR assays. MMP-2, -9 and TIMP-1 mRNA were expressed in the cultured RPE cells. The values of MMP-2/beta-actin in the cells treated with 0.1, 1.0, 10 ng/mL TGF-beta1 were 1.04 +/- 0.04, 1.07 +/- 0.02 and 1.11 +/- 0.03, respectively, significantly higher than in the control group (0.96 +/- 0.03, P < 0.05-0.01). The expression of MMP-2 mRNA could be up-regulated by TGF-beta1, in a dose-dependent manner. The expression of MMP-9 mRNA in the cultured RPE cells was slightly up-regulated by various TGF-beta1 concentrations treatment. The values of TIMP-1/beta-actin in the cells treated with 0.01 and 0.1 ng/ mL TGF-beta1 were 0.85 +/- 0.01 and 0.97 +/- 0.02 respectively, significantly lower than in the control group (1.07 +/- 0.04, P < 0.01), indicating that the expression of TIMP-1 mRNA was down-regulated by TGF-beta1 at low concentrations. But along with the increase of TGF-beta1 concentrations (1.0 and 10 ng/mL), the expression of TIMP-1 mRNA was slightly up-regulated, not significantly different from that in the control group (P > 0.05). It was concluded that TGF-beta1 might play an important role in the up-regulation of the expression of MMP-2 in RPE cells and result in a directional shift in the balance between MMP and TIMP. This may be facilitated for RPE cells to migrate in the pathogenesis of vitreoretinopathy.

The aim of this study was to explore the effect of small hairpin loop RNA (shRNA) silencing hypoxia-induced factor 1alpha (HIF-1alpha) gene on the expression of vascular endothelial growth factor (VEGF) and pigment epithelium derived factor (PEDF) in human retinal pigment epithelium (RPE) cells under hypoxic condition. Two target sites of HIF-1alpha mRNA were chosen and two kinds of shRNA were designed and synthesized against the target sites. Then the two kinds of shRNA were transfected into human RPE cells in vitro, respectively. These cells were cultured under hypoxic condition that was simulated by using 150 mumol/L CoCl(2). The mRNA expressions of HIF-1alpha, VEGF and PEDF were tested by semi-quantitative reverse transcription PCR (RT-PCR). The protein levels of HIF-1alpha, VEGF and PEDF were analyzed by Western blotting. After the two kinds of HIF-1alpha-specific shRNA were transfected into RPE cells respectively, the expression of HIF-1alpha mRNA and the levels of HIF-1alpha protein were decreased significantly in RPE cells under hypoxic condition. The expression of VEGF mRNA and the levels of protein significantly were also decreased. However, the levels of PEDF protein was significantly increased, but the expression of PEDF mRNA showed no significant changes. In conclusion, HIF-1alpha-specific shRNA can effectively silence the HIF-1alpha gene, and consequently down-regulate VEGF and up-regulate PEDF expression against hypoxia. These results reveal that HIF-1 is associated with posttranslational mechanism for down-regulating PEDF under hypoxia and provide an explanation for hypoxia-provoked increases in VEGF/PEDF ratios. These results also suggest that HIF-1 is one of the key cytokines to retinal neovascularization.

In order to explore the effect of high glucose concentration and high glucose concentration with hypoxia on the production of hypoxia-inducible factor-1alpha (HIF-1alpha) and vascular endothelial growth factor (VEGF), human RPE cells were cultured in 5.56 mmol/L glucose (control group), 5.56 mmol/L glucose with 150 micro mol/L CoCl2 (hypoxic group), 25 mmol/L glucose (high glucose group) and 25 mmol/L glucose with 150 micro mol/L CoCl2 (combination group). RT-PCR was used to detect the expression of HIF-1alpha and VEGF mRNAs. Western blot analysis was used to measure the levels of HIF-1alpha and VEGF proteins. Although the small amount of HIF-1alpha protein was able to be detected in high glucose group but not in control group, there was no significant difference between the expression of HIF-1alpha mRNA of RPE cells in high glucose group and that of RPE cells in control group. As compared with RPE cells in control group, the mRNA expression and the protein synthesis of VEGF in high glucose group were up-regulated. As compared with RPE cells in hypoxic group, the expression of HIF-1alpha mRNA of RPE cells in combination group was not different, but the protein synthesis of HIF-1alpha, the mRNA expression and the protein synthesis of VEGF were more obviously up-regulated. In conclusion, high concentration glucose mainly influence the protein synthesis of HIF-1alpha of RPE cell, and HIF-1alpha protein is able to be accumulated in high concentration glucose. Under hypoxia, the HIF-1alpha protein induced by high concentration glucose is more stable, and the expression of VEGF is obviously increased. It is suggested that high concentration glucose may play a role in retinal neovascularization, especially at ischemia stage of diabetic retinopathy.

An experimental model of rhegmatogenous retinal detachment (RRD) in rabbits was established to simulate the pathophysiologic condition of human RRD. 24 rabbits were randomly divided into 3 groups and underwent vitrectomy with a vitrector and/or retinotomy with a Charles flute needle, with 12 in group I (vitrectomy and retinotomy), 7 in group I (retinotomy) and 5 in group III (vitrectomy). All animals underwent follow-up examinations with direct and indirect ophthalmoscopy and fundus photography 12 h and day 1, 3, 5, 7, 10, 14, 21, and 28 after the procedure(s). Retinal changes were recorded. As a result, 10 RRDs were successfully established in group I. Direct and indirect ophthalmoscopy and fundus photography demonstrated typical features of RRD. No RRD developed in group II and III. It was concluded that the experimental rhegmatogenous retinal detachment produced in a rabbit model after vitrectomy with retinotomy in this study was a convenient and reliable one. This RRD model mimicked the typical pathophysiological changes in humans.
*Disease Models, Animal ; Random Allocation ; Retina/surgery ; *Retinal Detachment ; Vitrectomy

An experimental model of rhegmatogenous retinal detachment (RRD) in rabbits was established to simulate the pathophysiologic condition of human RRD. 24 rabbits were randomly divided into 3 groups and underwent vitrectomy with a vitrector and/or retinotomy with a Charles flute needle, with 12 in group I (vitrectomy and retinotomy), 7 in group I (retinotomy) and 5 in group III (vitrectomy). All animals underwent follow-up examinations with direct and indirect ophthalmoscopy and fundus photography 12 h and day 1, 3, 5, 7, 10, 14, 21, and 28 after the procedure(s). Retinal changes were recorded. As a result, 10 RRDs were successfully established in group I. Direct and indirect ophthalmoscopy and fundus photography demonstrated typical features of RRD. No RRD developed in group II and III. It was concluded that the experimental rhegmatogenous retinal detachment produced in a rabbit model after vitrectomy with retinotomy in this study was a convenient and reliable one. This RRD model mimicked the typical pathophysiological changes in humans.
Animals ; Disease Models, Animal ; Rabbits ; Random Allocation ; Retina ; surgery ; Retinal Detachment ; Vitrectomy

In order to investigate the effects of TGF-β1 on the expression of MMP-2, -9 and TIMP1 in human retinal pigment epithelial (RPE) cells, the third-sixth passage cultured RPE cells were treated with TGF-β~ at different concentrations (0.01, 0. 1, 1.0, 10 ng/mL), the expression of MMP-2, -9 and TIMP-1 mRNA was detected by semi-quantitative RT-PCR assays. MMP-2, -9 and TIMP-1 mRNA were expressed in the cultured RPE cells. The values of MMP-2/β-actin in the cells treated with 0.1, 1.0, 10 ng/mL TGF-β1 were 1.04±0.04, 1.07±0.02 and 1.11±0.03, respectively, significantly higher than in the control group (0. 96±0.03, P＜0. 05-0. 01). The expression of MMP-2 mRNA could be up-regulated by TGF-β1, in a dose-dependent manner. The expression of MMP-9 mRNA in the cultured RPE cells was slightly up-regulated by various TGF-β1 concentrations treatment. The values of TIMP-1/β-actin in the cells treated with 0.01 and 0. 1 ng/mL TGF-β1 were 0. 85±0.01 and 0.97 ± 0.02 respectively, significantly lower than in the control group (1.07±0.04, P＜0.01), indicating that the expression of TIMP-1 mRNA was down-regulated by TGF-β1 at low concentrations. But along with the increase of TGF-β1 concentrations (1.0 and 10 ng/mL), the expression of TIMP-1 mRNA was slightly up-regulated, not significantly different from that in the control group (P＞0.05). It was concluded that TGF-β1 might play an important role in the up-regulation of the expression of MMP-2 in RPE cells and result in a directional shift in the balance between MMP and TIMP. This may be facilitated for RPE cells to migrate in the pathogenesis of vitreoretinopathy.

In order to explore the effect of high glucose concentration and high glucose concentration with hypoxia on the production of hypoxia-inducible factor-1 α (HIF-1α) and vascular endothelial growth factor (VEGF), human RPE cells were cultured in 5.56 mmol/L glucose (control group), 5.56 mmol/L glucose with 150 μ mol/L CoCl2 (hypoxic group), 25 mmol/L glucose (high glucose group)and 25 mmol/L glucose with 150 μ mol/L CoCl2 (combination group). RT-PCR was used to detect the expression of HIF-1α and VEGF mRNAs. Western blot analysis was used to measure the levels of HIF-1α and VEGF proteins. Although the small amount of HIF-1α protein was able to be detected in high glucose group but not in control group, there was no significant difference between the expression of HIF-1α mRNA of RPE cells in high glucose group and that of RPE cells in control group.As compared with RPE cells in control group, the mRNA expression and the protein synthesis of VEGF in high glucose group were up-regulated. As compared with RPE cells in hypoxic group, the expression of HIF-1α mRNA of RPE cells in combination group was not different, but the protein synthesis of HIF-1 α, the mRNA expression and the protein synthesis of VEGF were more obviously up-regulated. In conclusion, high concentration glucose mainly influence the protein synthesis of HIF-1α of RPE cell, and HIF-1α protein is able to be accumulated in high concentration glucose.Under hypoxia, the HIF-1α protein induced by high concentration glucose is more stable, and the expression of VEGF is obviously increased. It is suggested that high concentration glucose may play a role in retinal neovascularization, especially at ischemia stage of diabetic retinopathy.