BACKGROUND:The plantarflexor weakness is a common muscle defect in patients with spastic cerebral palsy and Charcot-Marie-Tooth,which clinically manifests abnormal gaits,and the relationship between plantarflexor weakness and abnormal gaits is unclear. OBJECTIVE:To explore the biomechanical behavior of the lower limb under the action of a single factor of plantarflexor weakness to reveal the mechanism of abnormal gait induced by plantarflexor weakness and to provide guidance for the rehabilitation training of patients with plantarflexor weakness. METHODS:A predictive framework of musculoskeletal multibody dynamics in the sagittal plane was established based on OpenSim Moco to predict lower limb joint angles and muscle activation changes during walking in normal subjects.The validity of the framework was verified by combining the inverse kinematics and electromyogram activation time of the experimental data.Reduced isometric muscle forces were used to model plantarflexor weakness and to compare predicted lower extremity joint angles,joint moments,and muscle energy expenditure with normal subjects to analyze the effects of plantarflexor weakness on lower extremity biomechanics. RESULTS AND CONCLUSION:(1)The Moco-based prediction framework realistically predicted the biomechanical changes of the lower limbs during walking in normal subjects(joint angles:normalized correlation coefficient≥0.73,root mean square error≤7.10°).(2)The musculoskeletal model used a small stride support phase to increase the"heel-walking"gait during plantarflexor weakness.When the plantarflexor weakness reached 80%,the muscle energy expenditure was 5.691 4 J/kg/m,and the maximum activation levels of the gastrocnemius and soleus muscles were 0.72 and 0.53,which might cause the plantarflexor weakness patients to be more prone to fatigue when walking.(3)Muscle energy expenditure was significantly higher when the weakness of plantarflexors exceeded 40%,and the joint angles and moments of the lower limbs deteriorated significantly when the weakness of plantarflexors exceeded 60%,suggesting that there may be a"threshold"for the effect of plantarflexor weakness on gait,which may correspond to the point at which health care professionals should intervene in the clinical setting.

OBJECTIVE To explore the pharmacokinetic characteristics of 3 blood-absorbed components of Xiangshao sanjie oral liquid in rats with hyperplasia of mammary gland （HMG）. METHODS Female SD rats were divided into control group and HMG group according to body weight， with 6 rats in each group. The HMG group was given estrogen+progesterone to construct HMG model. After modeling， two groups were given 1.485 g/kg of Xiangshao sanjie oral liquid （calculated by crude drug） intragastrically， once a day， for 7 consecutive days. Blood samples were collected before the first administration （0 h）， and at 5， 15， 30 minutes and 1， 2， 4， 8， 12， 24 hours after the last administration， respectively. Using chlorzoxazone as the internal standard， the plasma concentrations of ferulic acid， paeoniflorin and rosmarinic acid in rats were detected by UPLC-Q/TOF-MS. The pharmacokinetic parameters [area under the drug time curve （AUC0－24 h， AUC0－∞）， mean residence time （MRT0－∞）， half-life （t1/2）， peak time （tmax）， peak concentration （cmax）] were calculated by the non-atrioventricular model using Phoenix WinNonlin 8.1 software. RESULTS Compared with the control group， the AUC0－24 h， AUC0－∞ and cmax of ferulic acid in the HMG group were significantly increased （P＜0.05）； the AUC0－24 h， AUC0－∞ ， MRT0－∞ ， t1/2 and cmax of paeoniflorin increased， but there was no significant difference between 2 groups （P＞0.05）； the AUC0－24 h and MRT0-∞ of rosmarinic acid were significantly increased or prolonged （P＜0.05）. C ONCLUSIONS In HMG model rats， the exposure of ferulic acid， paeoniflorin and rosmarinic acid in Xiangshao sanjie oral liquid all increase， and the retention time of rosmarinic acid is significantly prolonged.

Aim To investigate the mechanism of icar-itin(ICT)on D-galactose(D-gal)-induced TM4 ser-toli cell junctional function damage in vitro.Methods TM4 cells were divided into the normal control group and D-gal treatment group with different concentra-tions.The expression changes of TM 4 cell junction function-related proteins(ZO-1,Occludin,β-catenin and Cx43)and ERα/FAK signaling pathway-related proteins(ERα,FAK and pY397-FAK)were detected by Western blot.The concentration of ICT was screened by MTT method.TM4 cells were divided into normal control group,D-gal treatment group,and D-gal treatment+different concentrations of ICT group.The expression levels of the above proteins were detected by Western blot.Molecular docking was used to study the interaction between ERα and ICT,meanwhile predict the affinity between them.Finally,TM4 cells were di-vided into normal control group,D-gal treatment group,ERα inhibitor group,D-gal+ICT group,and ERα inhibitor+ICT group.The expression levels of the above proteins were detected by Western blot.Re-sults Compared with the normal control group,the ex-pression of junctional function-related proteins(ZO-1,Occludin,β-catenin and Cx43)and ERα/FAK signa-ling pathway-related proteins(ERα,FAK and pY397-FAK)were significantly down-regulated.After treat-ment with ICT,the expression of above proteins were significantly up-regulated.The docking results of ERα and ICT molecules revealed the formation of two hydro-gen bonds between Asp351 amino acid residue of ERα and ICT,with bond distances measuring 3.4? and 2.4?.Additionally,the docking binding energy be-tween them was found to be lower than-7 kcal·mol-1.After TM4 cells were treated with ERα inhibi-tor,the expression of above proteins and ERα/FAK signaling pathway-related proteins were significantly down-regulated,while the expression levels of the a-bove proteins did not change significantly after being given ICT protected group.Conclusions D-gal can cause damage to the junctional function of TM4 cells,and ICT can improve this damage,which may be related to the up-regulation of ERα/FAK signaling pathway.

Objective To compare the clinical outcomes of using elastic intramedullary nail and plate to fix fibular frac-ture.Methods The 60 patients with tibiofibular fractures admitted from January 2015 to December 2022 were divided into two groups:intramedullary nail group and plate group,30 cases each,intramedullary nail group was treated with elastic in-tramedullary nail fixation group,plate group was treated with steel plate and screw fixation group.Intramedullary nail group,there were 18 males and 12 females,aged from 22 to 75 years old with an average of(39.4±9.8)years old,including 24 cases of traffic accidents injury,6 cases of falling injury,23 cases of closed fractures,7 cases of open fractures.Steel plate group,there were 15 males and 15 females,aged from 24 to 78 years old with an average of(38.6±10.2)years old.The 22 cases were injured by traffic accident,8 cases were injured by falling.The 24 cases were closed fractures and 6 cases were open fractures.The operation time,intraoperative bleeding,American Orthopedic Foot and Ankle Society(AOFAS)ankle and hind foot scores,clinical healing time of fibula and the incidence of wound complications were compared between the two groups.Re-sults The patients in both groups were followed up for 6 to 21 months,with an average of(14.0±2.8)months.Compared with plate group,intramedullary nail group had shorter operative time,less bleeding,shorter clinical healing time of fibula,and low-er infection rate of incision,and the difference was statistically significant(P＜0.05).There were 2 cases of delayed healing in intramedullary nail group,1 case of nonunion in plate group,and 2 cases of delayed healing in plate group,and there was no statistically significant difference between the two groups(P＞0.05).In the last follow-up,according to the AOFAS scoring standard,the ankle function in intramedullary nail group was excellent in 17 cases,good in 12 cases,fair in 1 case,with an av-erage of(88.33±4.57)points,while in plate group,excellent in 16 cases,good in 10 cases,fair in 4 cases,with an average of(87.00±4.14)points;There was no statistical difference between the two groups(P＞0.05).Conclusion Elastic intramedullary nail has the advantages of short operation time,less intraoperative bleeding,short fracture healing time and less incision com-plications in the treatment of fibular fracture,which is worthy of clinical application.

Objective To investigate the application effect of grid-like locator in percutaneous transforaminal endoscopic discectomy(TESSYS)technology for lumbar disc herniation(LDH)in young adults.Methods Using a randomized controlled study method,102 young adults with LDH were included and divided into the control group and the observation group,with 51 cases in each group.Patients in the control group underwent TESSYS technology,while patients in the observation group underwent TESSYS technology with a grid-like locator.The perioperative indicators,complications,good to excellent surgical rate,the pre-and post-operative pain mediators[5-hydroxy-tryptamine(5-HT),substance P(SP)],Oswestry disability index(ODI),visual analogue scale(VAS),Cobb angle,and lumbar curvature index were compared between the two groups.Results The operation time of patients in the observation group was shorter than that of the control group,and the intraoperative blood loss and the number of intraoperative fluoroscopy were less than those of the control group(P＜0.05).The levels of serum 5-HT and SP,and VAS score 3 days after surgery in the observation group were lower than those in the control group(P＜0.05).There was no significant difference in the serum pain mediators,VAS scores,ODI scores,Cobb angles,or lumbar curvature indexes 3 months,6 months,and 12 months after surgery between the two groups(P＞0.05).There was no significant difference between the observation group and the control group in the incidence of complications(4.16％vs.10.64％),good to excellent surgical rate(89.58％vs.85.11％)12 months after surgery(P＞0.05).Conclusion The application of a grid-like locator in TESSYS technology for young adults with LDH can help to reduce the intraoperative fluoroscopy,alleviate pain symptoms,and shorten the operation time.

Serine/arginine-rich splicing factor 6 (SRSF6) is a member of the serine and arginine-rich (SR) protein family,and it plays a crucial regulatory role in RNA splicing.Dysregulation of SRSF6 ex-pression or function can lead to aberrant alternative splicing of certain genes,and contribute to the devel-opment and progression of inflammatory diseases,including tumors,diabetes,and pleural fibrosis.How-ever,the role of SRSF6 in inflammation remains unclear.In this study,we found that the expression of inflammatory factors,including tumor necrosis factor-α(TNF-α) and cyclooxygenase-2 (COX-2),was induced by lipopolysaccharides (LPS) .Concurrently,both the levels of SRSF6 mRNA and protein ex-pression significantly increased with prolonged LPS stimulation (P<0.05) .Furthermore,we investigated the change of SRSF6 expression on the expression of inflammatory factors.The results showed that upreg-ulation of SRSF6 enhanced the expression of LPS-induced inflammatory factors (P<0.05),while down-regulation of SRSF6 inhibited their expression (P<0.05) .Additionally,the activation of the nuclear fac-tor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways was suppressed by SRSF6 knockdown (P<0.05),indicating that SRSF6 is involved in regulating inflammatory responses in macrophages.Myeloid differentiation factor 88 (MyD88) is a key adaptor protein in the TLR4 signaling pathway,with its splicing isoforms MyD88-L and MyD88-S exerting pro-inflammatory and anti-inflamma-tory effects,respectively.Analysis of RNA-binding protein database and RNA immunoprecipitation showed that SRSF6 binds to MyD88 mRNA.Splicing analysis indicated that downregulation of SRSF6 promoted the expression of the anti-inflammatory MyD88-S mRNA isoform (P<0.01) .Moreover,knock-down of MyD88-S could rescue the expression of inflammatory factors suppressed by SRSF6 downregula-tion.These findings suggest that SRSF6 regulates MyD88 alternative splicing in macrophages,thereby af-fecting the activation of inflammatory signaling pathways and the expression of inflammatory factors.This study provides a foundation for further elucidating the role of SRSF6 in inflammatory diseases.

AIM To establish the quality standard of the zhujieshen Formula Granules based on standard decoction.METHODS The contents and transfer rates of ginsenoside Ro and chikusetsu saponin Ⅳa in standard decoction and formula granules were determined by HPLC,after which the transfer rates were calculated.The HPLC characteristic chromatograms of standard decoctions were established,after which cluster analysis and principal component analysis were adopted.Then the HPLC characteristic chromatograms of formula granules were established.RESULTS Nine common peaks were found in the HPLC characteristic chromatograms of seventeen batches of standard decoctions with the similarities of more than 0.9(except for S6,S12),which were clustered into two categories,and the accumulative variance contribution rate of three principal components reached 86.7％.The contents of ginsenoside Ro in three batches of formula granules were 83.1-88.6 mg/g,and the transfer rates were 53.1％-55.5％.The contents of chikusetsusaponin Ⅳa were 14.8-15.0 mg/g,and the transfer rates were 47.4％-48.1％.Nine common peaks were found in the HPLC characteristic chromatograms of three batches of formula granules with the similarities of 0.998,0.998 and 0.999,respectively.CONCLUSION This reasonable and reliable method can comprehensively evaluate the quality of Zhujieshen Formula Granules,and provide a reference for the quality control.

Objective To explore the safety and feasibility of a modified superior mesenteric artery(SMA)approach in totally laparoscopic complete mesocolic excision(CME)and D3 lymphadenectomy for right colon cancer.Methods A retrospective analysis was performed on clinical data of 77 cases of totally laparoscopic radical surgery for right colon cancer from April 2021 to April 2023.Before August 2022,42 cases underwent traditional SMA approach(control group,only marking with the ileocolic vascular pedicle as the tail of SMA),while after August 2022,35 cases underwent modified SMA approach(modified group,marking with the Treitz's ligament and ileocolic vascular pedicle as the head and tail of SMA,respectively).There was no statistically significant difference in general information between the two groups(P>0.05).The intraoperative conditions,postoperative recovery,and postoperative complications were compared between the two groups.Results Compared with the control group,the modified group had a shorter surgical time[(147.3±35.8)min vs.(173.4±29.9)min,t =-3.428,P =0.001].There were no statistically significant differences in the number of lymph node dissection,number of positive lymph nodes,drainage volume,exhaust time,postoperative hospital stay,and incidence of complications between the two groups(P>0.05).Conclusion The modified SMA approach for totally laparoscopic radical resection of right colon cancer shortens the surgical time,reduces the difficulty and risk of surgery,and has high safety and feasibility.

Objective To investigate the value of the human chorionic gonadotropin(hCG)stimulation test in the diagnosis of disorder of sexual development(DSD)in children.Methods A retrospective analysis was conducted on 132 children with DSD.According to the karyotype,they were divided into three groups:46,XX group(n=10),46,XY group(n=87),and sex chromosome abnormality group(n=35).The above groups were compared in terms of sex hormone levels before and after hCG stimulation test,and the morphological manifestation of the impact of testicular tissue on the results of the hCG stimulation test was analyzed.Results There was no significant difference in the multiple increase of testosterone after stimulation among the three groups(P>0.05).In the 46,XY group,the children with 5α-reductase type 2 deficiency had a testosterone-to-dihydrotestosterone ratio higher than that of the 46,XY DSD children with other causes.Morphological analysis showed that DSD children with testicular tissue demonstrated a significantly higher multiple increase in testosterone after stimulation compared to children without testicular tissue(P<0.05).Conclusions The hCG stimulation test has an important value in assessing the presence and function of testicular interstitial cells in children with different types of DSD,and it is recommended to perform the hCG stimulation test for DSD children with unclear gonadal type.[Chinese Journal of Contemporary Pediatrics,2024,26(2):158-163]

Objective To explore the value of transesophageal echocardiography(TEE)for surgical therapy of pediatric atrioventricular valve diseases.Methods Data of 273 children with atrioventricular valve diseases who underwent surgical operation under extracorporeal circulation were retrospectively analyzed.Transthoracic echocardiography(TTE)was performed within 1 week before,while TEE was performed before and after surgical operation.Whether TTE diagnosis should be adjusted were evaluated according to findings of TEE,so were the effects of surgical treatments,and the ultrasonic diagnostic coincidence rate before operation were compared taken surgical findings as standards.Results TEE was successfully completed in all 273 children.The diagnostic coincidence rate of preoperative TTE was 83.88％(229/273).After adjustment or supplement according to TEE in 44 cases(44/273,16.12％),the ultrasonic diagnostic coincidence rate reached 100％(273/273),higher than that of preoperative TTE alone(P＜0.001).Residual shunt was found in 5 cases,while no obvious improvement of valvular regurgitation was noticed in 3 cases with post operative TEE,and after corresponding treatments,re-examination of TEE showed satisfactory efficacy in all the above cases.Conclusion TEE could be used to accurately diagnose pediatric atrioventricular valve diseases before and evaluate the efficacy after surgical treatments,having important clinical application value.