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ObjectiveTo develop a new sutureless technique (photochemical tissue bonding,PTB ) for repair of corneal perforation. Methods A total of 60 rabbits were used for creating corneal perforation models.The corneal perforation on the left eye was repaired by sutures and the injury on the right eye was fixed with the use of amniotic membrane with PTB.The outcomes of the two mentioned repair methods were compared by observing the leakage of aqueous and the morphology of the anterior chamber at different instants,measuring the intraocular pressure (IOP) and observing the formation of neo-vessels and scars of cornea in the use of histological analysis. Results There was no leakage of aqueous and no difference for morphology evaluation in both treatments.PTB could adhere AM on the cornea to restore the corneal perforation.The peak IOP in the PTB treatment group at days 0,7 and 14 postoperative [ (531.2 ±49.5) mm Hg,(542.6 ±74.8) mm Hg and (603.9 ±69.1) mm Hg,respectively] was significantly higher than that in the suture group at the same instants [ (41.3 ±12.7) mm Hg,(142.6 ±25.4) mm Hg and (333.3 ± 66.7) mm Hg,respectively] (P ＜0.O1 ).Compared with suture repair,the treatment with PTB resulted in a better outcome of wound healing with less neo-vessels and less scars of cornea. Conclusion PTB treatment for repair of corneal perforation is superior to suture repair.
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Objective To establish a stable animal model for sequentially dynamic and direct monitoring of the skin wound infection. Methods The mice with full-thickness skin incisions were replicated. After immediate subcutaneous suture,the mice were randomly divided into four groups,ie,Group A was inoculated with 50 μl sterile PBS solution),Groups B,C and D were inoculated with 50 μl suspension containing 1 × 106,1 × 108 and 1 × 1010 colony forming unit (CFU)/ml bioluminescent methicillin-resistant staphylococcus aureus (MRSA) respectively.Then,the diet behavior of each group was observed and the mean weight and mortality of each group were also recorded at different time points.The bioluminescent intensity of fluoresce in the wounds was recorded at different time points by using the charge-coupled device (CCD) based imaging system.Local wound tissues were incised at 24 hours after inoculation for HE staining so as to observe wound inflammatory reaction in each group.Wound healing time of each group was also recorded. Results ( 1 ) Average weight:Groups A and B showed unobvious changes in weight; Group C lightened until day 3 after inoculation and then recovered gradually to the preinoculation level at day 14; Group D lightened gradually until death.(2)Mortality:Groups A and B had no death; Group C had 10％ deaths at day 14; Group D had 100％ deaths.(3) Bioluminescent intensity of wounds:Groups A and B showed a gradual weakened luminescence since the day of inoculation and had almost complete disappearance at days 5 and 7 respectively; there was no sign of obvious increase or decrease in Group C from the day of inoculation till day 14 ; Group D had a gradual increase since the day of inoculation and the luminous area expanded until the death.(4) HE staining at 24 hours after inoculation:all the four groups showed inflammatory cell infiltration,especially in Groups C and D.(5) Wound healing time:wound healed at days 5 and 7 after inoculation in Groups A and B; the wounds showed no healing even at day 14 in the Group C,but the wounds length and area did not show obvious enlargement or diminishment ; the wounds extended gradually until the death in the Group D,since the day of inoculation. Conclusions The inoculation of 50 μl suspension with 1 × 108 CFU/ml bioluminescent MRSA to full-thickness skin incision rats allows direct,real-time dynamic and continuous detection of the occurrence and development of the wound infections.The infection model is easy to make and has stability and high repeatability.
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Objective To study the effects of granulocyte-macrophage colony stimulating factor (GM-CSF) on the expression of vascular endotllelial growth factor (VEGF) in human dermal fibroblast. Methods In vitro human dermal fibroblasts in good status were incubated with GM-CSF (GM-CSF group) or non-GM-CSF (control group) culture medium for different periods of time. The mRNA, protein expression of VEGF in derma fibroblast were determined by reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting, respectively, and the secretion of VEGF in supernatant was measured by enzyme linked immunosorbant assay (ELISA). Results The expression of VEGF mRNA from dermal fibroblasts was increased significantly after l or more hours of incubation with GM-CSF comparing with the control (P＜0.05). 6 hours of stimulation by GM-CSF caused maximal expression of VEGF mRNA. The expression of VEGF protein in dermal fibroblasts was increased from 12 hours and was peaked at 24 hour after stimulation by GM-CSF. VEGF protein from the supernatant of the dermal fibroblasts was also raised persistently from 12 hour after stimulation by GM-CSF and was improved remarkably compared with the control. Conclusions GM-CSF can up-regulate directly the expression of VEGF in human derma fibroblast, which may be one of the mechanisms that GM-CSF accelerates neovascularization in wound healing.
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ObjectiveTo observe production of vascular endothelial growth factor (VEGF) induced by granulocyte/macrophage colony-stimulating factor (GMCSF)via ERK nerve growth factor (NF)-κB singling pathway in human fibroblasts during wound healing and explore relating mechanism.MethodsHuman fibroblasts from the injured skin were used for this study and treated with GMCSF.RT-PCR was used for analyzing the protein and mRNA levels of VEGF and Western blotting was employed to determine the phosphorylation of ERK. The fibroblasts were pre-treated with ERK specific inhibitor PD98059 and further treated with GMCSF, then the fibroblasts and the supernatant were collected for detection of protein level of VEGF by means of Western blot. ERK signal pathway was inhibited to detect the activation of NF-κB by means of immunofluorescence staining. Furthermore, the nuclear and cytoplasmic extraction kit was used to separate the cytoplasm and nucleus and Western blot employed for observation of the NF-κB activation. ResultsThe mRNA level and protein level of VEGF were increased significantly with treatment with higher concentration of GMCSF in a dose-dependent manner. VEGF mRNA level was increased two hours after administration with GMCSF and reached peak at 4-6 hours. GMCSF could remarkably activate the ERK phosphorylation. Compared with GMCSF, the ERK specific inhibitor PD98059inhibited significantly the effect of GMCSF in inducing VEGF expression (P ＜ 0.05). Western blot and immunofluorescence staining analyses showed that the activation of NF-ΚB was inhibited with reduced production of VEGF after GMCSF treatment.Conclusion GMCSF up-regulates production of VEGF through activating NF-κB via ERK signal pathway in the human fibroblasts.
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Objective To evaluate the effects of external substance P (SP) on scalding wound healing and neovascularization.Methods Eighty-four Wistar rats were induced into diabetic models by intraperitoneal injection of streptozotocin (STZ), and deep partial thickness scalding wound on the back with diameter of 2 cm was prepared. Rats were randomly divided into experiment group (n=42, local injection of SP) and control group (n=42, local injection of PBS). The process of wound healing was observed, and the percentages of wound closure were calculated on D0, D1, D3, D7, D10, D14, D21 post scald. The expression of CD31, surface marker of neovascular endothelial cells, was detected within the wound sites by immunohistochemical staining, and the microvessel density was calculated. Results The percentage of wound closure in experiment group was significantly higher than that in control group on D7 post scald [(42.69±3.26) % vs (30.24±1.17)%, P<0.01]. Immunohistochemical detection revealed that the expression of CD31 and the microvessel density in experiment group were significantly higher than those in control group from D7 post scald (P<0.01). ConclusionExternal SP may promote scalding wound healing in diabetic rats, the mechanism of which may be associated with upregulation of expression of CD31 and acceleration of neovascularization.
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To study the expression of some protooncogenes in burn wounded skin tissue. Methods: The protooncogene expression was analysed by mRNA dot blot hybridization,autoradiography and densitermeter. Results: Thermal injury induced C-myc, C-myb, C-jun and C-sis mRNA expression. How-ever, those four protooncogenes showed different expression models. Expression of C-myc and C-jun in-creased at d 1, and peaked 1 and 3 d postburn, respectively. Expression of C-myb and C-sis increased 3and 5 d, and peaked 10 d after thermal injury. Conclusion: Thermal injury can induce some protooncogeneexpression which sh0wed temporal order and well controlled manifestation. Those results suggest thatthose four protooncogenes are involved with the repair process as a regulator.