Objective To investigate the therapeutic effect of folic acid combined with decitabine in diabetic retinop-athy(DR)mice with different methylenetetrahydrofolate reductase(MTHFR)genotypes.Methods The DR model mice were created by mating 20 MTHFR-/-mice with 20 wild-type C57 mice.A random number table method was employed to allocate 20 successfully modelled mice into the model group,DAC group,FA group,and FA+DAC group,with five mice assigned to each group.Five untreated MTHFR-/-and wild-type mice served as normal control.After constructing the DR model,the DAC group was injected intraperitoneally with 0.25 mg·kg-1 decitabine once every 5 days;the FA group was given 70 μg·kg-1 folic acid by tube feed once a day;the FA+DAC group was given 0.25 mg·kg-1 decitabine and 70μg·kg-1 folic acid at the same time;and the normal group was given an equal amount of physiological saline.All of the above groups were intervened for 30 days.OCT was employed for the measurement of retinal thickness,OCTA for retinal vascular density,histopathology(HE staining)for pathological changes in the mouse retina,real-time fluorescence quanti-tative PCR for mRNA expression,and Western blot analysis for protein expression levels.Results Compared with the wild-type model group,the degree of increase in retinal thickness and vascular density in the retinal layer was more pro-nounced in the MTHFR-/-mice model group(all P＜0.05).In wild-type mice,retinal thickness and retinal layer vessel den-sity were reduced in the DAC,FA and FA+DAC groups compared to the model group,with the FA+DAC group show-ing the greatest degree of reduction.The differences were all statistically significant(all P＜0.05);In MTHFR-/-mice,reti-nal thickness and vascular density in the retinal layer were reduced in the DAC group and the FA+DAC group compared to the model group(allP＜0.05).HE staining results showed an increased extent of retinal damage in the MTHFR-/-mice model group compared with the wild-type mice model group.Compared with the model group,the DAC group and the FA+DAC group had thinner retinas and more aligned ganglion cell layers in all types of mice,with the FA group having a worse effect and the FA+DAC group having a better treatment effect.The results of the polymerase chain reaction(PCR)revealed that the relative expression of the SAHH,MAT2A and DNMT1 proteins in the retinal tissues of the wildtype and MTHFR-/-mice model groups was elevated in comparison to the control group(all P＜0.05).Furthermore,the relative mR-NA expression of the DAC,FA and FA+DAC groups was reduced in comparison to the model group(all P＜0.05).In wild-type mice,the relative expression of MTHFR protein mRNA was decreased in the model group compared with the con-trol group,and increased in the DAC group,FA group,and FA+DAC group compared with the model group(all P＜0.05).Western blot results showed that the relative expression of DNMT1,MAT2A and SAHH proteins in the retinal tissues of the wild-type and MTHFR-/-mice model groups was higher than that of the control group(all P＜0.05),and the relative expression was lower in the DAC,FA,and FA+DAC groups compared with that in the model group(all P＜0.05).In wild-type mice,the relative expression of MTHFR protein in the retinal tissue of the model group was lower than that of the control group,and the relative expression of MTHFR protein in the FA group and the FA+DAC group was elevated com-pared with that of the model group(all P＜0.05).Conclusion The protective effect of folic acid combined with decit-abine on DR was superior to that of decitabine alone;treatment with folic acid in combination with decitabine may have yielded better efficacy in wild-type DR mice.

Objective To investigate the therapeutic effect of folic acid combined with decitabine in diabetic retinop-athy(DR)mice with different methylenetetrahydrofolate reductase(MTHFR)genotypes.Methods The DR model mice were created by mating 20 MTHFR-/-mice with 20 wild-type C57 mice.A random number table method was employed to allocate 20 successfully modelled mice into the model group,DAC group,FA group,and FA+DAC group,with five mice assigned to each group.Five untreated MTHFR-/-and wild-type mice served as normal control.After constructing the DR model,the DAC group was injected intraperitoneally with 0.25 mg·kg-1 decitabine once every 5 days;the FA group was given 70 μg·kg-1 folic acid by tube feed once a day;the FA+DAC group was given 0.25 mg·kg-1 decitabine and 70μg·kg-1 folic acid at the same time;and the normal group was given an equal amount of physiological saline.All of the above groups were intervened for 30 days.OCT was employed for the measurement of retinal thickness,OCTA for retinal vascular density,histopathology(HE staining)for pathological changes in the mouse retina,real-time fluorescence quanti-tative PCR for mRNA expression,and Western blot analysis for protein expression levels.Results Compared with the wild-type model group,the degree of increase in retinal thickness and vascular density in the retinal layer was more pro-nounced in the MTHFR-/-mice model group(all P＜0.05).In wild-type mice,retinal thickness and retinal layer vessel den-sity were reduced in the DAC,FA and FA+DAC groups compared to the model group,with the FA+DAC group show-ing the greatest degree of reduction.The differences were all statistically significant(all P＜0.05);In MTHFR-/-mice,reti-nal thickness and vascular density in the retinal layer were reduced in the DAC group and the FA+DAC group compared to the model group(allP＜0.05).HE staining results showed an increased extent of retinal damage in the MTHFR-/-mice model group compared with the wild-type mice model group.Compared with the model group,the DAC group and the FA+DAC group had thinner retinas and more aligned ganglion cell layers in all types of mice,with the FA group having a worse effect and the FA+DAC group having a better treatment effect.The results of the polymerase chain reaction(PCR)revealed that the relative expression of the SAHH,MAT2A and DNMT1 proteins in the retinal tissues of the wildtype and MTHFR-/-mice model groups was elevated in comparison to the control group(all P＜0.05).Furthermore,the relative mR-NA expression of the DAC,FA and FA+DAC groups was reduced in comparison to the model group(all P＜0.05).In wild-type mice,the relative expression of MTHFR protein mRNA was decreased in the model group compared with the con-trol group,and increased in the DAC group,FA group,and FA+DAC group compared with the model group(all P＜0.05).Western blot results showed that the relative expression of DNMT1,MAT2A and SAHH proteins in the retinal tissues of the wild-type and MTHFR-/-mice model groups was higher than that of the control group(all P＜0.05),and the relative expression was lower in the DAC,FA,and FA+DAC groups compared with that in the model group(all P＜0.05).In wild-type mice,the relative expression of MTHFR protein in the retinal tissue of the model group was lower than that of the control group,and the relative expression of MTHFR protein in the FA group and the FA+DAC group was elevated com-pared with that of the model group(all P＜0.05).Conclusion The protective effect of folic acid combined with decit-abine on DR was superior to that of decitabine alone;treatment with folic acid in combination with decitabine may have yielded better efficacy in wild-type DR mice.

BACKGROUND: Hand metacarpophalangeal and interphalangeal joint defects caused by trauma, infection, tumor excision or congenital disease seriously affect hand function and contour. At present, there are many methods for the repair of hand bone or joint damage, but none of them can effectively reconstruct the joint anatomic structure and function to restore the normal activity function of joints. OBJECTIVE: To summarize the domestic and foreign researches on the reconstruction of injured hand bone or joint, and to explore the research status and progress of each method in recent years. RETRIEVAL STRATEGY: A computer-based online search of PubMed was undertaken to identify the English articles dated from January 1980 to August 2007 with the keywords "hand, bone and joint injury". In addition, we searched China Periodical Full-text Database, Wanfang Database, and VIP database for the related articles published in Chinese between January 1997 and August 2007-08 with the keywords "hand, bone and joint damage, treatment" in Chinese. We also manually searched the related books. Finally, 62 articles were collected. After the first trial, only articles closely correlated with treatment of hand joint damage, and published in the near future or in the authoritative journals were selected. Duplicated researches were excluded. LITERATURE EVALUATION: The articles mainly discussed the research progress in joint damage treatment. Of the 30 selected articles, 5 were review articles, and the others were clinical or basic experimental studies. DATA SYNTHESIS: Now, there are many methods for treating hand joint damage such as fusion of joint, arthroplasty, prosthetic replacement, joint transplantation, cartilage transplantation, cell transplantation, and tissue engineering technique. How to integrate the advantages of each therapy to explore more fast, effective, and low damage treatment methods has become the hot spot in present studies. CONCLUSION: Although the joint reconstruction in hand with bone or joint defects has made a great progress, it still needs further improvement in clinic. To explore fast, highly effective, and low damage treatment method is a hot spot in recent researches.

ive] To explore a new method of evaluating the healing of fractures. [Methods] Self-con trolled trial was applied. Bone mineral density ( BMD) of fracture end (region 3, R 3 ) and its neighboring proximal and distal regions ( R 2 and R 1 respectively) in 126 cases of fracture of lower end of radius was deter mined by dual-energy X-ray absorptionmetry. [Results] BMD of R3 elevated as compared with that of R 2 and R1 (P