A comparative study on the transplantation of different concentrations of human umbilical mesenchymal cells into diabetic rats

AIM: To observe the effects of intravitreal injections of different concentrations of human umbilical mesenchymal stem cells on retinopathy in rats with diabetes mellitus.METHODS: Healthy and adult male Sprague-Dawley(SD) rats were randomly assigned to a normal control group(group A), a diabetic retinopathy(DR) blank control group(group B), a high-concentration transplantation group(group C), a low-concentration transplantation group(group D) and a placebo transplantation group(group E). The expression of nerve growth factor(NGF)protein in the retinal layers was detected by immunohistochemical staining at 2, 4, 6 and 8wk.RESULTS: The expression of NGF was positive in group A and most positive in the retinal ganglion cell layer. In groups B and E, the expression of NGF was positive 2wk after transplantation and showed an increase in all layers. However, the level of expression had decreased in all layers at 4wk and was significantly reduced at 8wk. In groups C and D, the expression of NGF had increased at 2wk and continued to increase up to 8wk. The level of expression in group C was much higher than that in group D.CONCLUSION: DR can be improved by intravitreal injection of human umbilical mesenchymal stem cells.High concentrations of human umbilical mesenchymal stem cells confer a better protective effect on DR than low concentrations.

Visual function and vision-related quality of life after vitrectomy for idiopathic macular hole: a 12mo followup study

· AIM: To investigate the visual function and the relationship with vision-related quality of life(VRQOL)after macular hole repair surgery.· METHODS: Prospective case series. Thirty-six consecutive eyes in 36 patients who underwent pars plana vitrectomy(PPV) and internal limiting membrane(ILM) peeling were included. The 25-item National Eye Institute Visual Function Questionnaire(VFQ-25) was answered by the participants before and 3 and 12 mo after operation. Follow-up visits examinations included best-corrected visual acuity(BCVA), clinical examination,and central macular thickness(CMT) measured by optical coherence tomography(OCT).·RESULTS: Macular-hole closure was achieved in 35 of36 eyes(97.2%). At baseline and months 3 and 12, the log MAR BCVAs(mean±SD) were 1.15±0.47, 0.68±0.53(P 【0.0001 versus baseline), and 0.55 ±0.49(P 【0.001 versus baseline, P =0.273 versus month 3), respectively; the CMTs(μm) were 330 ±81, 244 ±62(P 【0.001 versus baseline), and 225±58(P 【0.001 versus baseline, P =0.222 versus month 3), respectively; the median preoperative VFQ-25 composite score of 73.50(63.92-81.13) increased postoperatively to 85.50(80.04-89.63) at 3mo(P 【0.001)and 86.73(82.50-89.63) at 12mo(P 【0.001) respectively.The improved BCVA was correlated with improvements in five subscales(r =-0.605 to-0.336, P 【0.001 to P =0.046) at 12 mo.· CONCLUSION: PPV with ILM peeling improved anatomic outcome, visual function, and VRQOL. Theimproved BCVA was an important factor related to the improved VRQOL.