Objective To observe angiogenic effect of platelet-released growth factors (PRGF) from platelet-rich plasma (PRP) on mierovessel formation at early stage after anterior crueiate ligament (ACL) reconstruction by freeze-dried Achilles tendon. Methods The study involved 14 rabbits, of which 12 rabbits were used as experiment group and the other 2 as control group. In the experiment group, after two sides of rabbit ACL were removed, freeze-dried Achilles tendon treated by PRGF was transplanted into random one side of the knee to substitute the original ACL (PRGF group), while the other side was transplanted with freeze-dried Achilles tendon treated only by normal saline (NS group). Only one side of the knee was removed in the control group. The grafts were observed by HE and immuno- histeehemical staining 2, 4 and 6 weeks after operation. Microvessel density (MVD) was measured by Weidner method. Results Compared with NS group, MVD in PRGF group was significant higher at 2,4 and 6 weeks after operation (P<0.05). MVD of NS group at 2,4 and 6 weeks after operation was 2.52±0.45, 3.41±0.44 and 2.57±0.51 respectively, but that of PRGF group at 2,4 and 6 weeks af- ter operation was 3.56±0.81,4.91±0.46 and 3.01±0.75 respectively (P<0.05). The time of neo- vascular formation and the depth of vascular penetration into the grafts of the PRGF group were superior to those of NS group. Conclusion PRGF can significantly promote microvessel formation at early stage after ACL reconstruction with freeze-dried Achilles tendon.

Objective To observe the effect of platelet-rich plasma(PRP)gel on tendon-bone healing following tendon allograft reconstruction of anterior cruciate ligament(ACL).Methods Bilateral ACL reconstructions using Achilles tendon allografts were performed in 24 New Zealand white rabbits matured skeletally.One knee joint was pretreated with the allograft PRP gel(served as experimental group),while the contralateral knee joint was free from treatment with PRP(served as control group).The reconstructions were assessed histologically,immunohistochemically and biomechanically at 2,6 and 12 weeks.Results At 2 and 6 weeks,Burak scores of experimental group were higher than control group.At 12 weeks,the grafts showed a mature zone of fibrocartilage in experimental group but mature scar tissues on the tendon-bone surface.Immunohistochemistry demonstrated early higher expression of VEGF in experimental group than control group and continually higher expression of TGF-β1 in experimental than control group.In contrast,the grafts of the controls group revealed the development of mature scar tissue resembling Sharpey fibers spanning the tendon-bone interface.At 2 and 6 weeks,the biomechanical analysis revealed the limit load of(15.3±2.9)N and(33.2±6.9)N respectively in experimental group,which were significantly higher than(7.9±1.4)N and(23.7±4.9)N in control group (P ＜ 0.05).Conclusion Application of PRP is the potential means to enhance the earlier healing of the allograft tendon-bone.

Objective:To investigate the effects of riboflavin-ultraviolet A scleral collagen cross-linking on the retina under different irradiation time, and to determine the safe irradiation time.Methods:Sixty healthy New Zealand white rabbits were randomly divided into control group (0 minute group), 10 minutes group, 20 minutes group, 30 minutes group and 40 minutes irradiation group according to the irradiation time, with 12 rabbits in each group.The left eye was irradiated with riboflavin-ultraviolet A scleral collagen (370 nm, 10 mW/cm 2). The histopathological change of retina was observed by light microscope and transmission electron microscope and compared among different groups.The concentration of MDA and the activities of SOD, CAT and GSH-Px in retinal tissue were detected by corresponding kits.The expression levels of SOD and CAT proteins in retinal tissue were detected by Western blot method.The study protocol was approved by the Binzhou Medical University Laboratory Animal Ethical Committee (No.2017-80). The use and care of animals complied with the statement of ARVO and the Regulation on the Management of Laboratory Animal Quality of China. Results:Under the light microscope, the structure of the retinas in the control group was orderly arranged.Under the transmission electron microscope, the lamellar structure in the inner segment and the mitochondrial structure in the outer segment of the photoreceptor cells were intact, and the mitochondrial ridge was continuous in the control group.There was no obvious difference in retinal morphology between the 10 minutes irradiation group and the control group under both the light microscope and the transmission electron microscope, and the retinal damage became more severe with the prolongation of irradiation time.The concentration of MDA in the retina of each group was elevated gradually with the increase of irradiation time, and the difference was statistically significant ( F=65.25, P<0.05). The concentration of MDA was (11.31±1.84), (14.94±1.04)and (18.25±1.42)nmol/mgprot in the 20 minutes, 30 minutes and 40 minutes irradiation groups respectively, which were significantly higher than (1.13±0.02)nmol/mgprot in the control group (all at P<0.05). The MDA concentration in 20 minutes, 30 minutes and 40 minutes irradiation groups was increased successively, showing statistically significant differences (all at P<0.05). With the prolongation of irradiation time, the activities of SOD, CAT and GSH-Px as well as the expression levels of SOD and CAT proteins were significantly decreased gradually ( F=44.09, 34.18, 35.60, 115.75, 78.86; all at P<0.05). The differences between the control group and 20 minutes, 30 minutes, 40 minutes irradiation groups, and the differences among 20 minutes, 30 minutes, 40 minutes irradiation groups were statistically significant (all at P<0.05). Conclusions:Riboflavin-ultraviolet A 10 mW/cm 2 scleral collagen cross-linking irradiation for 10 minutes is safe.Excessive irradiation time can cause damage to the retina of rabits.

Objective: To study the relationship between the development of hepatocellular carcinoma(HCC) and HBV gene characteristics among the HCC patients with hepatitis B virus (HBV) infection. Methods: Some acute and chronic hepatitis B patients were collected as control group and HBV associated HCC patients as HCC group. Serum samples of subjects were tested for HBV serological markers. HBV DNA of those samples had been extracted and nested PCR was used to amplify the sequence of HBV DNA. Furthermore, MEGA 6.0 and Bioedit softwares were used to made phylogenetic trees and analyze the gene mutations. Results: The sequences of S region and BCP/Precore region of HBV were amplified from 86 samples in study group and 39 samples in control group. The prevalence of PreS deletion, A1762T and A1762T/G1764A in HCC group were 39.53%, 74.42% and 72.09% respectively, and in control group were 20.51%, 53.85% and 53.85% respectively. The statistical differences of them were significant. The prevalence of A1762T and A1762T/G1764A in ≥ 50 years group were higher than that of < 50 years group. The prevalence of A1762T, G1764A and A1762T/G1764A of subjects who infected genotype C were higher than those infected genotype B. On the contrary, the prevalence of G1896A of subjects who infected genotype C were lower than that of genotype B. It was found that ≥ 50 years, genotype C and G1896A mutation were independently associated with HCC. The risk for suffer from HCC of ≥50 years group, genotype C group and G1896A group were 9.349, 28.875 and 7.648 times compared with < 50 years group genotype B group and without G1896A mutation group, respectively. Conclusions The population of ≥50 years or genotype C had a higher prevalence of A1762T, A1762T/G1764A, ≥50years、genotype C、G1896A were independently associated with HCC, as compared with the subjects of the control group.