Objective To study the effect and mechanism of action of Yi Sui Sheng Xue Fang(YSSX)in ameliorating chemotherapy-induced renal injury in mice through The Kelch-like ECH-associated protein 1(KEAP1)/Nuclear factor erythroid-derived 2-like 2(NRF2)signalling pathway.Methods A mouse kidney injury model was induced by intraperitoneal injection of carboplatin(40 mg·kg-1).C57BL/6 mice were randomly divided into blank group(0.9％NaCl),model group(kidney injury model)and experimental-L,experimental-M,experimental-H groups(0.53,1.05 and 2.10 g·kg-1·d-1 YSSX by gavage for 7 d).Keap1 and Nrf2 were determined by Western blot;superoxide dismutase(SOD)and malondialdehyde(MDA)activities were determined by spectrophotometry.Results The protein expression levels of Keap1 in blank group,model group and experimental-L,experimental-M,experimental-H groups were 0.26±0.02,0.64±0.03,0.59±0.01,0.45±0.05 and 0.34±0.02;the protein expression levels of Nrf2 were 0.69±0.06,0.35±0.01,0.36±0.01,0.48±0.02 and 0.56±0.01;the enzyme activities of catalase(CAT)were(572.49±912.92),(334.60±4.92),(402.76±9.80),(475.35±5.21)and(493.00±12.03)U·mg-1;glutathione(GSH)were(2.79±0.06),(0.51±0.01),(0.59±0.07),(1.29±0.04)and(1.70±0.08)μmol·L1;SOD were(477.00±4.32),(260.67±6.13),(272.67±2.87),(386.33±3.68)and(395.00±12.25)U·mL-1;MDA were(3.89±0.02),(7.32±0.03),(6.94±0.14),(4.60±0.01)and(4.34±0.02)nmol·mg prot-1.The differences of the above indexes in the model group compared with the blank group were statistically significant(P＜0.01,P＜0.001);the differences of the above indexes in experimental-M,experimental-H groups compared withe model group were statistically significant(P＜0.01,P＜0.001).Conclusion YSSX can activate Keap1/Nrf2 signaling pathway and regulate the oxidative stress state of the organism,thus improving the renal injury caused by chemotherapy in mice.

Objective To investigate the impact of emodin(EM)on vascular endothelial cell injury in rats with diabetes macroangiopathy by regulating hypoxia inducible factor-1α(HIF-1α)/vascular endothelial growth factor(VEGF)signaling pathway.Methods SD rats were divided into blank group and modeling group,the rats in the modeling group were fed with high fat and high sugar combined with N-nitro-L-arginine methyl ester to build the diabetes macroangiopathy model,and the blank group was fed with ordinary diet.The vascular endothelial cells successfully isolated from the thoracic aorta of rats in blank group and modeling group were named control group and model group,respectively.The vascular endothelial cells in the modeling group were divided into model group,dimethyloxallyl glycine(DMOG)group(10 μmol·L-1DMOG),combined group(80 mg·L-1EM+10 μmol·L-1 DMOG)and experimental-L,-M,-H groups(20,40,80 mg·L-1 EM).The apoptosis of rat vascular endothelial cells was detected by flow cytometry;Western blot was applied to detect the expression of HIF-1αand VEGF proteins in rat vascular endothelial cells.Results The apoptosis rates of vascular endothelial cells in experimental-M,-H groups,DMOG group,combined group,model group and control group were(10.18±0.36)％,(6.28±0.20)％,(24.96±1.18)％,(12.36±0.49)％,(18.76±0.68)％and(4.59±0.26)％;HIF-1α protein levels were 0.96±0.07,0.78±0.06,2.03±0.12,1.05±0.13,1.58±0.12 and 0.69±0.05;VEGF protein levels were 0.59±0.05,0.23±0.02,0.98±0.06,0.63±0.04,0.86±0.07 and 0.11±0.01.The above indexes in the model group were compared with the control,DMOG,experimental-M and experimental-H groups,and the above indexes in the combined group were compared with the experimental-H group,and the differences were statistically significant(all P＜0.05).Conclusion EM may inhibit HIF-1α/VEGF pathway to improve vascular endothelial cell injury in rats with diabetes macroangiopathy.

Traditional Chinese medicine can regulate the hypoxia-inducible factor-1α(HIF-1α)signalling pathway and slow down tumour progression mainly by inhibiting tumour angiogenesis,glycolysis,epithelial mesenchymal transition and other pathological processes.This paper,starting from HIF-1α and related factors,reviews its pathological mechanism in tumours and the research of traditional Chinese medicine interventions with the aim of providing theoretical references for the treatment of tumours with traditional Chinese medicine.

Objective To establish a method for testing isolated mitral valve in vitro and quantitatively evaluate the effect of transcatheter edge-to-edge repair technology(TEER)on functional mitral regurgitation(FMR)(non-A2-P2 regurgitation).Methods In this study,an FMR(non-A2-P2 regurgitation)model was developed by dilating the annulus orifice and displacing the papillary muscle in isolated porcine mitral valve.The hydrodynamics characteristics of 6 valves were tested by a pulsatile flow testing system under different physiological and pathological conditions before and after TEER.Results The results show that the valve regurgitation improved from moderate-severe[regurgitant fraction(60.2±17.5)％]to mild-moderate[regurgitant fraction(34.7±12.0)％]by repair(P＜0.001).The EOA[(3.8±1.6)cm2 vs.(2.2±0.5)cm2,P＜0.001]and the forward cross valve pressure difference[(1.8±1.3)mmHg vs.(3.8± 1.8)mmHg,P＜0.001],which characterize the forward flow performance of the valve,were compared before and after repair,and the differences were statistically significant.At the same time,the repair caused valve stenosis(the effective orifice area decreased by 40％and the positive differential pressure increased by 110％),but the valves was still within the normal physiological range,and no iatrogenic stenosis was caused.Conclusions It can be seen that TEER has an effect on FMR.This study provides validation and evaluation methods in vitro for expanding indications and improving TEER,and reference for developing standards of transcatheter valve repair testing in vitro.

ObjectiveDnaG primase in Mycobacterium tuberculosis (MtuDnaG) plays a vital role in DNA replication, making it a target for novel antituberculosis drug discovery. However, the mechanism of MtuDnaG priming is not fully understood, which hinders the screening of MtuDnaG inhibitors. In this work, the specific recognition sites (SRS) in ssDNA for MtuDnaG binding was investigated and the interactions between MtuDnaG and ssDNA template was discussed. MethodsBy biochemical and biophysical methods, the binding of the didomain of MtuDnaG (MtuP49, containing the zinc-binding domain and RNA polymerase domain) to ssDNA template with various trinucleotide sites was evaluated, the affinity of MtuP49 to ssDNA template was measured. ResultsThe present study suggested the 5'-GCG/C-3' as the potential SRS in ssDNA for specific binding to MtuDnaG. Besides,5'-GCG/C-3' sites were further identified within the oriC region of M. tuberculosis genome. Importantly, the 3' sequence flanking the 5'-GCG/C-3' site markedly affected the binding affinity of ssDNA to MtuP49. Mutagenesis studies showed that substitution of residue Arg31 in the zinc-binding domain affected the binding activity of MtuP49 to template ssDNA. Combined with the predicted structure of MtuP49, an intramolecular rearrangement of zinc-binding domain relative to the RNA polymerase domain was implied to be essential in the binding of MtuP49 to template ssDNA. ConclusionThis study firstly identified the SRS in ssDNA for MtuDnaG binding, the key factors affecting MtuDnaG binding to ssDNA was revealed. The above results provide evidence to shed light on the mechanism of MtuDnaG priming, and pave the way for development of novel DnaG-targeted antituberculosis drugs.

This study aimed to investigate the effect of iron overload on the transplant outcomes of pediatric patients with severe aplastic anemia (SAA) undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT). A retrospective analysis was conducted on the clinical data of 74 children with SAA who received allo-HSCT at the Hematology Department of Wuhan Children’s Hospital between January 2018 and August 2022. Children with iron overload (serum ferritin >1 000 μg/L) before transplantation had a longer disease course, received more red blood cell transfusions, and had a higher number of CD34 + cells infused. Moreover, iron overload significantly delayed the reconstitution of regulatory T cells after transplantation, increasing the incidence of hemorrhagic cystitis and grade Ⅲ-Ⅳ acute graft-versus-host disease after transplantation. However, iron overload did not significantly affect the overall survival and failure-free survival rates of the children.

Spinal muscular atrophy(SMA)is an autosomal recessive neuromuscular disorder.With the emergence of disease-modifying therapies,the prognosis of SMA has significantly improved,drawing increased attention to the importance of home rehabilitation and nursing management.Long-term,standardized home rehabilitation and nursing can delay the progression of SMA,enhance the psychological well-being,and improve the quality of life of both patients and caregivers.This article provides an overview of the goals of home rehabilitation,basic functional training methods,respiratory management,and nutritional management for SMA patients,as well as psychological health issues,emphasizing the significance of obtaining appropriate home rehabilitation and support during the care process.[Chinese Journal of Contemporary Pediatrics,2024,26(4):420-424]

Objective To explore early postoperative gait characteristics and clinical outcomes after total knee arthroplasty(TKA).Methods From February 2023 to July 2023,26 patients with unilateral knee osteoarthritis(KOA)were treated with TKA,including 4 males and 22 females,aged from 57 to 85 years old with an average of(67.58±6.49)years old;body mass in-dex(BMI)ranged from 18.83 to 38.28 kg·m-2 with an average of(26.43±4.15)kg·m-2;14 patients on the left side,12 pa-tients on the right side;according to Kellgren-Lawrence(K-L)classification,6 patients with grade Ⅲ and 20 patients with grade Ⅳ;the courses of disease ranged from 1 to 14 years with an average of(5.54±3.29)years.Images and videos of standing up and walking,walking side shot,squatting and supine kneeling were taken with smart phones before operation and 6 weeks after operation.The human posture estimation framework OpenPose were used to analyze stride frequency,step length,step length,step speed,active knee knee bending angle,stride length,double support phase time,as well as maximum hip flexion angle and maximum knee bending angle on squatting position.Western Ontario and McMaster Universities(WOMAC)arthritis index and Knee Society Score(KSS)were used to evaluate clinical efficacy of knee joint.Results All patients were followed up for 5 to 7 weeks with an average of(6.00±0.57)weeks.The total score of WOMAC decreased from(64.85±11.54)before op-eration to(45.81±7.91)at 6 weeks after operation(P＜0.001).The total KSS was increased from(101.19±9.58)before opera-tion to(125.50±10.32)at 6 weeks after operation(P＜0.001).The gait speed,stride frequency and stride length of the affected side before operation were(0.32±0.10)m·s-1,(96.35±24.18)steps·min-1,(0.72±0.14)m,respectively;and increased to(0.48±0.11)m·s 1,(104.20±22.53)steps·min-1,(0.79±0.10)m at 6 weeks after operation(P＜0.05).The lower limb support time and active knee bending angle decreased from(0.31±0.38)sand(125.21±11.64)° before operation to(0.11±0.04)s and(120.01±13.35)° at 6 weeks after operation(P＜0.05).Eleven patients could able to complete squat before operation,13 patients could able to complete at 6 weeks after operation,and 9 patients could able to complete both before operation and 6 weeks after operation.In 9 patients,the maximum bending angle of crouching position was increased from 76.29° to 124.11° before operation to 91.35° to 134.12° at 6 weeks after operation,and the maximum bending angle of hip was increased from 103.70° to 147.25° before operation to 118.61° to 149.48° at 6 weeks after operation.Conclusion Gait analysis technology based on artificial intelligence image recognition is a safe and effective method to quantitatively identify the changes of pa-tients'gait.Knee pain of KOA was relieved and the function was improved,the supporting ability of the affected limb was im-proved after TKA,and the patient's stride frequency,stride length and stride speed were improved,and the overall movement rhythm of both lower limbs are more coordinated.

Objective To compare the efficacy of renal proximal renal artery denervation(pRDN)and full-length renal artery denervation(fRDN)for treatment of hypertension.Methods Fifty-six hypertensive patients were enrolled and randomly assigned to full-length renal artery denervation group(n=25)and proximal renal artery denervation group(n=31).After the procedure,24-hour ambulatory blood pressure monitoring(24 h-ABPM)at 6 months and office blood pressure at 12 months was recorded for statistical analysis.Results The blood pressure at follow-up reduced significantly in both groups,while there was no significant difference between groups.The baseline office blood pressure in fRDN group and pRDN group was(180±15)/(104±10)mmHg and(180±12)/(103±8)mmHg,respectively,which decreased to(142±9)/(82±7)mmHg and(143±10)/(83±6)mmHg at 12 months postoperatively(P＜0.001 within groups and P＞0.05 between groups).The baseline 24 h-ABPM in the two groups was(162±13)/(95±8)mmHg and(160±12)/(94±8)mmHg,respectively,which decreased to(142±11)/(83±7)mmHg and(141±8)/(81±7)mmHg at 6 months postoperatively(P＜0.001 within groups and P＞0.05 between groups).However,there was no significant difference in the reduction of office blood pressure and ambulatory blood pressure between the two groups.No treatment-related adverse events were observed.Conclusions pRDN has similar antihypertensive effect to fRDN.

This study was aimed at creating an engineered strain of Bacillus subtilis for efficient expression of biologically active type 2 toxin B(TcdB2)derived from a highly virulent strain of Clostridium difficile.The TcdB2 gene was cloned from ST1/RT027 strain genome DNA,incorporated into the PHT01 vector,and then transformed into B.subtilis strain WB800N for prokaryotic expression.Cell toxicity assays revealed that the recombinant TcdB2 exhibited cytotoxic effects in various cells.The engineered B.subtilis strain effectively expressed biologically active TcdB2,thus providing a basis for further exploration of the pathogenic mechanisms of highly virulent strains of C.difficile and establishing a foundation for potential vaccine can-didate targets.