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 analyze the reverse mechano-electric effect of the layered structure of articular cartilage and its influencing factors.Methods The cartilage samples were classified according to their physiological thickness(approximately 0.4 mm for the upper layer,1 mm for the middle layer,and 0.6 mm for the lower layer).Through a non-contact external electric field testing method,how different influencing factors affected the reverse mechano-electric effect of articular cartilage was analyzed.Results When the electric field spacing decreased,water content increased,and in vitro time decreased,the displacement of normal layered cartilage in a non-contact electric field increased by 18,10,15 μm,respectively.In the case of simulated arthritis defects,as the defect depth and radius increased,the overall deviation deflection of articular cartilage gradually decreased by about 7 μm.Conclusions The three-layer cartilage differed in their reverse mechano-electricity effects,showing the greatest deflection in the middle layer at 90％water content,under 7 mm electric field spacing,and after 12 hours ex vivo.

Objective To analyze the reverse mechano-electric effect of the layered structure of articular cartilage and its influencing factors.Methods The cartilage samples were classified according to their physiological thickness(approximately 0.4 mm for the upper layer,1 mm for the middle layer,and 0.6 mm for the lower layer).Through a non-contact external electric field testing method,how different influencing factors affected the reverse mechano-electric effect of articular cartilage was analyzed.Results When the electric field spacing decreased,water content increased,and in vitro time decreased,the displacement of normal layered cartilage in a non-contact electric field increased by 18,10,15 μm,respectively.In the case of simulated arthritis defects,as the defect depth and radius increased,the overall deviation deflection of articular cartilage gradually decreased by about 7 μm.Conclusions The three-layer cartilage differed in their reverse mechano-electricity effects,showing the greatest deflection in the middle layer at 90％water content,under 7 mm electric field spacing,and after 12 hours ex vivo.

Objective:To explore the safety and efficacy of intraosseous regional administration (IORA) of vancomycin for preventing infection in primary total knee arthroplasty (TKA).Methods:A total of 124 patients with knee osteoarthritis undergoing TKA between February 2024 and May 2024 at nine hospitals were enrolled. Preoperative infection prophylaxis involved either IORA (0.5 g vancomycin administered via intraosseous regional infusion before incision) or intravenous infusion (1 g vancomycin via peripheral vein). The IORA group included 15 males and 47 females with a median age of 66.5 years (range, 60.0-70.0 years), while the intravenous group included 14 males and 48 females with a median age of 66.0 years (range, 61.8-70.3 years) years. Intraoperative samples were collected including fat and synovium tissues after incision, before prosthesis placement, and after tourniquet release; distal femoral cancellous bone during femoral osteotomy; proximal tibial cancellous bone during tibial osteotomy; proximal intercondylar cancellous bone before prosthesis placement; and peripheral blood from non-infused arms at surgery initiation and after tourniquet release. Vancomycin concentrations were measured using liquid chromatography-tandem mass spectrometry. Vital sign changes were recorded from admission to 5~10 minutes post-IORA (IORA group) or post-incision (intravenous group). Follow-ups were conducted on postoperative day 1 and 3, and at 1 and 3 months, to document complications including IORA-related adverse events, periprosthetic joint infections, surgical site infections, red man syndrome, acute kidney injury, deep vein thrombosis and so on.Results:Vancomycin concentrations in bone, fat, and synovial tissue samples were significantly higher in the IORA group than in the intravenous group ( P<0.05), while vancomycin concentrations in blood samples were significantly lower in the IORA group than in the intravenous group ( P<0.05). Only 7.3%(41/558) of tissue samples in the IORA group had vancomycin concentrations below 2.0 μg/g (the minimum inhibitory concentration of vancomycin against coagulase-negative staphylococcus), compared to 59.3%(331/558) in the intravenous group (χ 2=11.285, P<0.001). In the intravenous group, 16.9%(21/124) of blood samples had vancomycin concentrations exceeding 15.0 mg/L (the threshold associated with a significantly increased risk of nephrotoxicity), while all concentrations in the IORA group were below this threshold, the difference was statistically significant (χ 2=22.943, P<0.001). There were no statistically significant difference ( P>0.05) in vital signs changes before and after vancomycin administration between the two groups. Two patients in the intravenous group experienced incision exudate, while no other related complications occurred in either group. Conclusions:Compared to the traditional intravenous infusion of 1 g vancomycin, intraosseous injection of a low dose (0.5 g) of vancomycin achieves higher local tissue concentrations in the knee joint with a lower incidence of adverse reactions and is safe for infection prophylaxis. Despite guidelines not recommending the routine use of vancomycin for preventing infection after primary TKA, intraosseous injection of 0.5 g vancomycin may be considered intraoperatively for primary TKA in the following scenarios: patients in medical institutions with a high prevalence of methicillin-resistant staphylococcus aureus (MRSA) infections, patients with potential preoperative MRSA colonization, or patients with cephalosporin allergy.

Objective: To understand the unhealthy listening habits and related factors hearing on impairment among primary and middle school students in Jilin Province, so as to provide a scientific basis for the prevention of hearing impairment in children and adolescents. Methods: From September to November 2021, a stratified cluster random sampling method was employed to select 12 847 primary and middle school students in nine cities of Jilin Province who use headphones for more than 0.5 hours daily for a questionnaire survey. Data on unhealthy listening habits, lifestyle habits and hearing impairment were collected. The data were analyzed using the χ 2 test and Logistic regression. Results: Totally 1 702 students(13.25%) experienced hearing impairment within the last month. There were statistical differences between the sexes with the average daily headphone use, the times of using headphones ≥1 h every day for one week use in all environment or noisy environment ( χ 2=47.86, 57.60, 66.31, P <0.01). Logistic regression analysis results showed that factors related to the occurrence of hearing impairment among primary and secondary school students included:average daily headphone use of 1-2 h and more than 2 h ( OR=1.74, 95%CI =1.60-1.90; OR=1.73, 95%CI =1.59-1.90), times of using headphones ≥1 h every day for one week were 1-2 times and >2 times ( OR=1.71, 95%CI =1.59- 1.84 ; OR=1.83, 95%CI =1.71-1.97), the times of using headphones≥1 h every day for one week being 1-2 times and >2 times in noisy environment per week ( OR=1.48, 95%CI =1.40-1.56; OR=1.72, 95%CI =1.61-1.86), economic underdevelopment ( OR=1.85, 95%CI =1.76-1.96), boarding （OR=1.78, 95%CI =1.69-1.89), single parent family ( OR=1.72, 95%CI =1.60- 1.87 ), daily activity duration less than 1 h ( OR=1.71, 95%CI =1.63-1.81), sedentary behavior duration more than 6 h per day ( OR=1.88, 95%CI =1.79-1.98) ( P <0.05). Conclusions The behavior of ear protection among primary and middle school students in Jilin Province needs to be enhanced, focusing on students in economically underdeveloped areas, boarding schools and single parent families. It is necessary to guide primary and middle school students to improve their bad ear habits, increase outdoor activities and reduce the time of sitting.

Objective:To explore the safety and efficacy of intraosseous regional administration (IORA) of vancomycin for preventing infection in primary total knee arthroplasty (TKA).Methods:A total of 124 patients with knee osteoarthritis undergoing TKA between February 2024 and May 2024 at nine hospitals were enrolled. Preoperative infection prophylaxis involved either IORA (0.5 g vancomycin administered via intraosseous regional infusion before incision) or intravenous infusion (1 g vancomycin via peripheral vein). The IORA group included 15 males and 47 females with a median age of 66.5 years (range, 60.0-70.0 years), while the intravenous group included 14 males and 48 females with a median age of 66.0 years (range, 61.8-70.3 years) years. Intraoperative samples were collected including fat and synovium tissues after incision, before prosthesis placement, and after tourniquet release; distal femoral cancellous bone during femoral osteotomy; proximal tibial cancellous bone during tibial osteotomy; proximal intercondylar cancellous bone before prosthesis placement; and peripheral blood from non-infused arms at surgery initiation and after tourniquet release. Vancomycin concentrations were measured using liquid chromatography-tandem mass spectrometry. Vital sign changes were recorded from admission to 5~10 minutes post-IORA (IORA group) or post-incision (intravenous group). Follow-ups were conducted on postoperative day 1 and 3, and at 1 and 3 months, to document complications including IORA-related adverse events, periprosthetic joint infections, surgical site infections, red man syndrome, acute kidney injury, deep vein thrombosis and so on.Results:Vancomycin concentrations in bone, fat, and synovial tissue samples were significantly higher in the IORA group than in the intravenous group ( P<0.05), while vancomycin concentrations in blood samples were significantly lower in the IORA group than in the intravenous group ( P<0.05). Only 7.3%(41/558) of tissue samples in the IORA group had vancomycin concentrations below 2.0 μg/g (the minimum inhibitory concentration of vancomycin against coagulase-negative staphylococcus), compared to 59.3%(331/558) in the intravenous group (χ 2=11.285, P<0.001). In the intravenous group, 16.9%(21/124) of blood samples had vancomycin concentrations exceeding 15.0 mg/L (the threshold associated with a significantly increased risk of nephrotoxicity), while all concentrations in the IORA group were below this threshold, the difference was statistically significant (χ 2=22.943, P<0.001). There were no statistically significant difference ( P>0.05) in vital signs changes before and after vancomycin administration between the two groups. Two patients in the intravenous group experienced incision exudate, while no other related complications occurred in either group. Conclusions:Compared to the traditional intravenous infusion of 1 g vancomycin, intraosseous injection of a low dose (0.5 g) of vancomycin achieves higher local tissue concentrations in the knee joint with a lower incidence of adverse reactions and is safe for infection prophylaxis. Despite guidelines not recommending the routine use of vancomycin for preventing infection after primary TKA, intraosseous injection of 0.5 g vancomycin may be considered intraoperatively for primary TKA in the following scenarios: patients in medical institutions with a high prevalence of methicillin-resistant staphylococcus aureus (MRSA) infections, patients with potential preoperative MRSA colonization, or patients with cephalosporin allergy.

Objective To investigate the clinical effect of dapagliflozin combined with sacubitril-valsar-tan in the treatment of non-reduced ejection fraction type heart failure(non-HFrEF).Methods A total of 120 patients with non-HFrEF diagnosed and treated in this hospital from January to December 2022 were selected as the study subjects and divided into the observation group and control group by the random number method,60 cases in each group.The both groups were treated with conventional treatments such as β-receptor blockers and diuretics,the patients in the control group were treated with sacubitril-valsartan(Noxinto),and the pa-tients in the observation group were treated with dapagliflozin on the basis of the control group for 6 months.The clinical efficacy,serum N-terminal B-type natriuretic peptide precursor(NT-proBNP),hypersensitivity-C-reactive protein(hs-CRP),serum creatinine(SCr),serum potassium,cardiac color Doppler ultrasound param-eters,6 min walk test(6MWT)distance before treatment and in 6 months after treatment,and the occurrence of major adverse cardiovascular events(MACE)during treatment were compared between the two groups.Re-sults After 6 months of treatment,the total effective rate in the observation group was 93.3%,which was higher than 80%in the control group,and the difference was statistically significant(P=0.032).After 6 months of treatment,the levels of NT-proBNP and hs-CRP in the two groups were significantly decreased compared with those before treatment,moreover the observation group was lower than the control group,and the difference was statistically significant(P<0.05).After 6 months of treatment,LVEF and 6MWT dis-tance in the two groups were increased compared with those before treatment,LVEDV and LVESV were de-creased compared with those before treatment,moreover the change amplitude of the above indexes in the ob-servation group were greater than those in the control group,and the differences were statistically significant(P<0.05).The incidence rate of MACE in the observation group was lower than that in the control group(16.7%vs.5.0%),and the difference was statistically significant(P<0.05).Conclusion Dapagliflozin combined with sacubitril-valsartan in the treatment of non-HFrEF could significantly reduce the levels of NT-proBNP and hs-CRP,improve the cardiac function,increase the exercise tolerance,decrease the incidence rate of MACE and improve the prognosis.

Liver transplantation is the ultimate treatment for patients with end-stage liver disease.In recent years,significant progress has been made in technological innovation and perioperative management,but its efficacy is still limited by challenges such as donor liver shortage and postoperative cardiopulmonary fail-ure.Extracorporeal membrane oxygenation(ECMO),as a cardiopulmonary support technique,provides oxy-genation and hemodynamic stability through extracorporeal circulation,demonstrating multidimensional value in the field of liver transplantation,especially in donor liver preservation and the management of complex com-plications.This article reviews the research progress of ECMO application in liver transplantation,facilitating a deeper understanding of the current status and future development directions of this technology in liver transplantation,providing references for clinical practice and scientific research.

Ursodeoxycholic acid(UDCA)is a naturally occurring,low-toxicity,and hydrophilic bile acid(BA)in the human body that is converted by intestinal flora using primary BA.Solute carrier family 7 member 11(SLC7A11)functions to uptake extracellular cystine in exchange for glutamate,and is highly expressed in a variety of human cancers.Retroperitoneal liposarcoma(RLPS)refers to liposarcoma originating from the retroperitoneal area.Lipidomics analysis revealed that UDCA was one of the most significantly down-regulated metabolites in sera of RIPS patients compared with healthy subjects.The augmentation of UDCA concentration(≥25 μg/mL)demonstrated a suppressive effect on the proliferation of liposarcoma cells.[15N2]-cystine and[13Cs]-glutamine isotope tracing revealed that UDCA impairs cystine uptake and glutathione(GSH)synthesis.Mechanistically,UDCA binds to the cystine transporter SLC7A11 to inhibit cystine uptake and impair GSH de novo synthesis,leading to reactive oxygen species(ROS)accumulation and mitochondrial oxidative damage.Furthermore,UDCA can promote the anti-cancer effects of ferroptosis inducers(Erastin,RSL3),the murine double minute 2(MDM2)inhibitors(Nutlin 3a,RG7112),cyclin dependent kinase 4(CDK4)inhibitor(Abemaciclib),and glutaminase inhibitor(CB839).Together,UDCA functions as a cystine exchange factor that binds to SLC7A11 for antitumor activity,and SLC7A11 is not only a new transporter for BA but also a clinically applicable target for UDCA.More importantly,in combination with other antitumor chemotherapy or physiotherapy treatments,UDCA may provide effective and promising treatment strategies for RLPS or other types of tumors in a ROS-dependent manner.

BACKGROUND: To date, results on relationship between CYP3A4 gene polymorphism were limited and inconclusive, and no study focused on the influence of CYP3A4 gene-obesity interaction on breast cancer risk, especially in Chinese women. The purpose of this study was to evaluate the impact of four single nucleotide polymorphisms (SNPs) of CYP3A4 gene, the SNP-SNP and gene-environment interactions on the susceptibility to breast cancer in Chinese women. METHODS: Logistic regression was used to explore the relationship between four SNPs of CYP3A4 gene and the risk of breast cancer. Generalized multifactor dimensionality reduction (GMDR) was used to screen the best SNP-SNP and gene-abdominal obesity interaction combinations among four SNPs and abdominal obesity. Haplotype examination among 4 SNPs was conducted using the SHEsis web-based platform. RESULTS: Logistic regression analysis showed that carriers of rs2242480- T allele have significantly higher breast cancer risk, than those with rs2242480- CC genotype, adjusted OR (95%CI) was 1.68 (1.23-2.16) and 2.03 (1.53-2.58) for participants with CT genotype and TT genotype under additive model. We did not find any notable interactions between the four SNPs within the CYP3A4 gene. GMDR model found a significant association in a two-locus model involving rs2242480 and obesity, with a p-value of 0.018. Stratified analysis found that breast cancer risk was the highest in obese participants with rs2242480- CT or TT genotype, compared to those non-obese participants with rs2242480- CC genotype, OR (95%CI) was 3.02 (1.83-4.25). We found that all haplotype combinations were not correlated with breast cancer risk. CONCLUSIONS We found that the T allele of rs2242480 within the CYP3A4 gene and interaction between rs2242480 and obesity were associated with an increased risk of breast cancer. However, the results of this study were only applicable to the Han ethnic group and cannot be generalized to other ethnic groups in China, and more SNPs of CYP3A4 gene should been enrolled in the analysis in the future, to verify the results obtained in this study.
Adult ; Aged ; Female ; Humans ; Middle Aged ; Breast Neoplasms/etiology* ; China/epidemiology* ; Cytochrome P-450 CYP3A/metabolism* ; Gene-Environment Interaction ; Genetic Predisposition to Disease ; Haplotypes ; Obesity/epidemiology* ; Polymorphism, Single Nucleotide ; Risk Factors ; East Asian People