Objective To determine the acute effects of blood flow restriction(BFR)running warm-up on Achilles tendon morphology and function in basketball players in order to provide a theoretical basis for optimizing warm-up protocols for military personnel and athletes susceptible to Achilles tendon injuries.Methods Twenty-seven male basketball players were subjected and asked to participate in 3 different running warm-up protocols:low-speed running(LSR),high-speed running(HSR),and BFR combined with LSR(BFR-LSR).The acute changes in Achilles tendon morphology,mechanical properties,and functional performance across the 3 testing sessions were analyzed and compared.Results Immediately after training,both HSR warm-up and BFR-LSR warm-up significantly improved Achilles tendon thickness,blood flow,stiffness,and gastrocnemius maximal voluntary isometric contraction(MVIC)when compared with LSR warm-up(P<0.05).No statistical differences were observed in above indicators between the BFR-LSR and HSR warm-ups(P>0.05).24 hours after training,compared with LSR warm-up,HSR warm-up still significantly improved Achilles tendon thickness,blood flow,stiffness,and gastrocnemius MVIC(P<0.05).Although BFR-LSR warm-up did not show statistically significant differences in these parameters compared to LSR warm-up,it still demonstrated positive trends.Immediately and 24 h after training,no obvious difference were found in jump performance among the 3 warm-up protocols(P>0.05),but,both BFR-LSR and HSR warm-ups exhibited superior performance than LSR warm-up.Conclusion Immediately after training,BFR-LSR warm-up demonstrates comparable effects to the HSR warm-up on improving Achilles tendon morphology and performance,as well as enhancing jump performance.However,its sustained and long-term effects require further investigation.

Objective To investigate the effect of blood flow restriction combined with low-intensity plyometric jump training(LI-PJT+BFR)on lower limb dynamic postural control of functional ankle instability(FAI)in college students. Methods From March to May,2023,40 FAI college students were recruited from Xi'an Physical Education University,and randomly divided into high-intensity plyometric jump training(HI-PJT,n = 14)group,low-intensity plyomet-ric jump training(LI-PJT,n = 13)group and LI-PJT+BFR group(n = 13).All the groups finished the six-week corresponding training.The maximum voluntary isometric contraction(MVIC)of tibialis anterior,peroneus lon-gus,lateral head of gastrocnemius,gluteus maximus,vastus lateralis,biceps femoris and semitendinosus were measured,and the root mean square(RMS)of electromyography of these muscles was measured during the sin-gle-leg landing(SLL),using wireless surface electromyography before and after intervention.Moreover,they were assessed with Y-balance test and Cumberland Ankle Instability Tool(CAIT). Results MVIC and RMS of the target muscles improved after intervention in all the groups(t>2.218,P<0.05),except MVIC and RMS of peroneus longus,gluteus maximus,biceps femoris and semitendinosus in LI-PJT group,and RMS of peroneus longus in LI-PJT+BFR group;and MVIC and RMS of the target muscles were the least in LI-PJT group(F>3.262,P<0.05),except those of peroneus longus.The extension scores of Y-balance test and the total score improved after intervention(t>2.485,P<0.05),and they were the least in LI-PJT group(F>5.042,P<0.05).The CAIT score improved after intervention(t>5.227,P<0.001),and it was the least in LI-PJT group(F = 4.640,P<0.05). Conclusion LI-PJT+BFR could improve lower limb dynamic postural control of FAI college students,which is similar to HI-PJT.

Objective To study the potency of transdifferentiated renal tubular epithelial cells for acquiring the tissue stem cells during renal fibrosis.Methods The in vitro cellular model of renal tubular epithelial cells(NRK-52E)transdifferentiation under the inflammatory environment of the local renin-angiotensin (AngⅡ)system was established.The expression and change situation of the embryonic kidney developmental gene Pax2 and the tissue stem cell surface marker CD133 were observed.Results Local high concentration of AngⅡcould stimulate the NRK-52E cells to express Pax2 and CD133 molecule,its effect demonstrated the dose-and time-dependent relation.Conclusion The inflammatory damage leads to the transdifferentiated renal tubular epithelial cells po-tency to acquire the tissue stem cell.