ObjectiveTaking the cuproptosis/oxidative stress pathway as the entry point， this study investigated the effect and mechanism of Liangyi Paste on hepatic lipid deposition in naturally aged mice fed with a high-fat diet. MethodsAfter adaptive feeding， 80 ten-week-old male C57BL/6 mice were used. Thirty of them were randomly divided into three groups （10 mice per group）： The 12-month-old control group （12MCON）， the 15-month-old control group （15MCON）， and the 15-month-old group with a high-fat diet （15MHFD）. The 12MCON and 15MCON groups were continuously fed a standard diet， while the 15MHFD group started receiving a high-fat diet at 12 months of age. Tissue samples were collected at the corresponding time points for each group. The remaining 50 mice were randomly divided into five groups （10 mice per group）： the 20-month-old control group （20MCON）， the model group， and the low-， medium-， and high-dose Liangyi Paste groups （2.91 ， 5.82 ， 11.64 g·kg^-1·d^-1， respectively）. The 20MCON group was continuously fed a standard diet， while the other groups started receiving a high-fat diet at 15 months of age. At 18 months of age， the Liangyi Paste groups were administered the corresponding doses of Liangyi Paste by gavage， while the 20MCON and model groups were given an equal volume of saline by gavage. After 8 weeks of continuous gavage （when the mice reached 20 months of age）， tissue samples were collected. Hepatic TG levels were measured using assay kits； liver histology and lipid deposition were observed via hematoxylin-eosin （HE） and oil red O staining； reactive oxygen species （ROS） were detected by enzyme-linked immunosorbent assay （ELISA）； Cu²⁺， superoxide dismutase （SOD）， and malondialdehyde （MDA） levels were measured by colorimetry； mRNA and protein expression of genes related to cuproptosis and oxidative stress pathways were analyzed by Real-time polymerase chain reaction（Real-time PCR） and Wes automated protein expression system. ResultsCompared with 12MCON， the 15MCON group showed significantly increased hepatic TG， Cu²⁺， ROS， and MDA levels （P<0.01）， decreased SOD （P<0.01）， hepatocyte swelling， and disordered arrangement. The mRNA and protein levels of ferredoxin 1 （FDX1）， dihydrolipoamide S-acetyltransferase （DLAT）， heat shock protein 70 （HSP70）， dihydrolipoamide dehydrogenase （DLD）， pyruvate dehydrogenase E1 subunit-β （PDHB）， nuclear factor erythroid 2-related factor 2 （Nrf2）， and peroxisome proliferator-activated receptor γ （PPARγ） were significantly elevated （P<0.05， P<0.01）. Compared with 15MCON group， the 15MHFD and 20MCON groups exhibited further increases in TG， Cu²⁺， ROS， and MDA （P<0.01）， reduced SOD （P<0.01）， and aggravated hepatocyte swelling and disorder. There were increased lipid droplets with mild vacuolization in the 15MHFD group， and no significant lipid deposition was observed in the 20MCON group. FDX1， DLAT， HSP70， DLD， PDHB， Nrf2， and PPARγ mRNA and protein levels were significantly increased （P<0.05， P<0.01）. Compared with 20MCON group， the model group demonstrated markedly elevated TG， Cu²⁺， ROS， and MDA （P<0.01）， reduced SOD （P<0.01）， severe hepatic steatosis， and upregulated expression of FDX1， DLAT， HSP70， DLD， PDHB， Nrf2， and PPARγ mRNA and proteins （P<0.05， P<0.01）. All abnormalities were significantly reversed after Liangyi Paste treatment. ConclusionLiangyi paste can ameliorate hepatic lipid deposition in naturally aged mice with a high-fat diet by modulating the cuproptosis/oxidative stress pathway.

Objective To evaluate the dissolution effects of pediatric ammonium urate stones in solutions with different pH values, so as to provide reference for the clinical treatment of this type of stones. Methods Eight pure ammonium urate stones(ammonium urate content ≥90%)of similar size and mass(median mass 4.6 g)were obtained from 8 children(＜14 years)undergoing percutaneous nephrolithotomy at the People's Hospital of Xinjiang Uygur Autonomous Region. The stones were placed in sodium chloride solutions with pH values of 5.0, 6.0, 7.0, and 8.5 and artificial urine with pH values of 4. 6, 5.0, 7.0, and 8.5 at a constant temperature of 37 ℃. The mass of the stones was recorded before placement and at 24, 48, and 72 h after placement. The dissolution rates of the stones were calculated. Results The pediatric ammonium urate stones could be dissolved in sodium chloride solution, and the total dissolution rate was the highest(94.6%)after 72 hours when the pH value was 6.0. The total dissolution rate of ammonium urate stones in artificial urine after 72 hours were all over 50%, and the total dissolution rate was the highest(79.7%)when the pH value was 4.6. Conclusion Pediatric ammonium urate stones are soluble in sodium chloride solution and artificial urine, and the total dissolution rate is higher in acidic environment.

Objective:To observe the efficacy and safety of combined lienal polypeptide injection therapy in the treatment of Mycoplasma pneumoniae pneumonia（MPP）in children aged 3 to 14 years old in multiple clinical centers.Methods:A randomized，controlled，multi-center clinical study design was adopted.A total of 240 hospitalized children aged 3 to 14 years old with MPP from 7 hospitals from September 1，2023 to January 31，2024 were included.According to the severity of pneumonia，they were divided into the mild MPP group with 80 cases and the severe MPP/refractory MPP（SMPP/RMPP）group with 160 cases，and then randomly divided into the control group and the experimental group at a ratio of 1 ∶1，using the random number table method.After screening，subjects entered a treatment period of 5 to 7 days.The control group was treated with azithromycin，while the experimental group was treated with azithromycin plus lienal polypeptide injection .The recovery of lung CT，length of hospital stay，duration of fever，cough score，whether mild cases developed into severe or refractory cases，duration of hormone use，use of intravenous immunoglobulin（IVIG），bronchoscopy treatment，and immune function were observed between the two groups to evaluate the efficacy of lienal polypeptide injection.Adverse events after medication，vital signs，blood routine，urine routine，liver function，myocardial enzymes，renal function，and electrocardiogram were observed to evaluate the safety. Results:A total of 231 subjects have completed the trial in the 7 hospitals，including 118 cases in the experimental group and 113 cases in the control group.Main observation index：the rate of lung CT aggravation in the experimental group was lower than that in the control group（2.6% vs 15.3%， P<0.01），and the difference was statistically significant.Secondary indexes：there were no statistically significant differences in the length of hospital stay，duration of fever，cough score，duration of hormone use，whether IVIG treatment was used，the number of bronchoscopy treatment cases，and immunoglobulin between the two groups（all P>0.05）.However，the rate of cases of plastic bronchitis（PB）found under bronchoscopy in the experimental group was lower than that in the control group（0 vs 18.8%， P=0.03），and the difference was statistically significant.Among the mild MPP（72 cases），there were no statistically significant differences in the length of hospital stay，duration of fever，cough score，duration of hormone use，whether IVIG treatment was used，the number of bronchoscopy treatment cases，and the improvement rate of lung CT between the two groups（all P>0.05）.However，compared with the control group，the rate of cases developing into SMPP/RMPP in the experimental group was less（24.3% vs 48.6%， P=0.03），and the difference in IgG before and after treatment was small［0.53（-0.04，1.18）g/L vs 1.33（0.48，2.25）g/L， P=0.01］.Among the SMPP/RMPP cases（159 cases），the rate of cases of PB found under bronchoscopy in the experimental group was less than that in the control group（0 vs 20%， P=0.04），and the rate of cases with aggravated lung CT in the experimental group was less than that in the control group（1.3% vs 19.5%， P<0.01），and the improvement rate of lung CT in the experimental group was higher than that in the control group（88.8% vs 75.3%， P=0.03），with statistically significant differences.There were no statistically significant differences in the length of hospital stay，duration of fever，cough score，duration of hormone use，whether IVIG treatment was used，the number of bronchoscopy treatment cases，and immunoglobulin between the two groups（all P>0.05）.Two cases in the experimental group developed rashes，which improved after the drug was discontinued.There were no serious adverse reactions such as abnormal vital signs like dyspnea and cyanosis due to the use of lienal polypeptide injection.There were no obvious changes in blood routine，liver function，myocardial enzymes，renal function，electrocardiogram，and urine routine values before and after medication compared with the baseline. Conclusion:The combined use of lienal polypeptide injection in the treatment of MPP in children can reduce the probability of the transformation from mild cases to SMPP/RMPP，reduce the rate of aggravation of the image findings，promote the absorption of lung inflammation，reduce the rate of PB found under bronchoscopy，and has good safety.

BACKGROUND:Knee finite element modelling can provide insight into knee mechanics,but its complex image segmentation is more difficult for researchers.With the development of deep learning techniques,deep learning techniques have been widely used in knee joint finite element modelling.OBJECTIVE:To replace the manual segmentation step in finite element modelling of the knee joint by using 3D Swin UNETR in combination with a semi-automatic segmentation technique for statistical shape models.METHODS:Manual(artificial)knee joint finite element model was developed based on MR and semi-automatic knee joint finite element model was developed based on 3D Swin UNETR+statistical shape model segmentation.The same loads and boundary conditions were applied to both models.Validation was performed by calculating the Dice similarity coefficient,mean distance,and comparing the peak equivalent stresses,maximum principal stresses,and maximum shear stresses of the two models.RESULTS AND CONCLUSION:(1)The Dice similarity coefficients of the manual and semi-automatic segmented femur and tibia were more than 98％,and the average distances were less than or equal to(0.35±0.08)mm.(2)With the longitudinal load of 750 N and 10 Nm internal overturning moment applied to the femur tip of both manual and semi-automatic finite element models,the peak equivalent stress,maximum principal stress,and maximum shear stresses of meniscus in manual finite element model were 14.12,18.54,and 7.35 MPa;peak equivalent force,maximum principal stress,and maximum shear stress of femoral cartilage were 2.22,2.15,and 1.18 MPa;peak equivalent force,maximum principal stress,and maximum shear stress of tibial cartilage were 2.50,1.91,and 1.41 MPa;semi-automatic finite element model of meniscus:peak equivalent force,maximum principal stress,and maximum shear stress were 14.93,18.53,and 7.75 MPa.The peak equivalent force,maximum principal stress,and maximum shear stress of femoral cartilage were 2.26,2.18,and 1.20 MPa;the peak equivalent stress,maximum principal stress,and maximum shear stress of tibial cartilage were 2.60,1.91,and 1.46 MPa.The peak equivalent stress,maximum principal stress,and maximum shear stress of manual and semi-automatic finite element models were basically consistent,with no significant difference(P＞0.05).(3)The semi-automatic segmentation technique proposed in this study can replace manual segmentation in creating accurate finite element models of the knee joint.

Objective:To investigate the clinicopathological and molecular genetic characteristics of pediatric tumors with DICER1 mutations.Methods:A total of 90 patients diagnosed with various types of pediatric tumors at Beijing Children′s Hospital, Capital Medical University, Beijing, China from July 2023 to September 2025 were included in this study. PCR amplification and Sanger sequencing were performed to detect the coding-region mutations of the DICER1 gene. The clinical, histopathological, and molecular genetic features of the cases with DICER1 mutation were then analyzed.Results:Among the 90 patients, 39 were male and 51 were female, with an age of onset ranging from 1 month to 17 years [median 7.13 (2.77, 10.37) years]. DICER1 mutations were detected in 37 patients (37/90, 41.1%). Among them, 9 cases harbored one mutation [6 pleuropulmonary blastomas (PPBs), 2 sex cord stromal tumors (SCSTs), and 1 cystic nephroma (CN)], 27 cases carried two mutations [10 PPBs, 3 anaplastic sarcomas of the kidney (ASKs), 3 SCSTs, 3 thyroid adenoma, 2 nodular thyroid goiters, 2 thyroid follicular lesions, 2 CN, 1 embryonal rhabdomyosarcoma, and 1 case with multiple primary tumors], and 1 case exhibited three mutations (bilateral ASKs). Despite variations in the site of origin, DICER1-mutant tumors shared several morphological features. Grossly, they presented as multilocular cystic, cystic-solid to solid masses. Microscopically, they exhibited a subepithelial layer of mesenchymal cells, with focal rhabdomyoblastic/chondroid/chondrosarcomatous differentiation, as well as cellular anaplasia. Germline testing using peripheral blood in the 31 patients with DICER1 mutation confirmed germline origin in 61.3% (19/31) of them. Parental analysis ( n=12) demonstrated genetic inheritance in 8 cases, predominantly from families with tumor history. Germline variants scattered throughout DICER1 and consisted of loss-of-function mutations (nonsense, frameshift, and splice-site). Somatic mutations showed distinct clustering in exons 24 and 25 hotspots (codons 1705, 1709, 1809, 1810 and 1813), primarily missense variants. Notably, one multiple primary tumor case harbored a somatic mosaic p.E1705K mutation. Conclusions:DICER1 mutations are frequently detected in pediatric PPB, CN, SCST, ASK, nodular thyroid goiter, thyroid adenoma, and genitourinary rhabdomyosarcoma, which often represent as the index case of DICER1 syndrome. Performing DICER1 mutation testing in these patients not only facilitates tumor diagnosis and secondary cancer surveillance, but also enables the comprehensive genetic risk assessment and management for patient′s family members.

Objective To design a high altitude adaptive oxygen generator for the crews to alleviate their high altitude reaction in high altitude environment and meet their requirements for oxygen supply.Methods A high altitude adaptive oxygen generator based on the mature pressure swing adsorption oxygen production method was designed with the key technologies of discharge capacity compensation of air compression pump and airway fusion of molecular sieve tower,which had the components of molecular sieve tower,air compression pump,controller,cooling fan,cooler,solenoid valve,regulator,flow meter and etc.Trials were carried out at the simulated altitude and field plateau environment so as to verify the high altitude adaptive performance of the oxygen generator developed.Results The trial results showed the oxygen generator met the desired objectives and the requirements for oxygen volume fraction in GJB 2799-1996 General specification for medical oxygen generator using molecular sieve method.Conclusion The oxygen generartor provides oxygen supply effectively for vehicle operators in plateau environments or the ones rushing into the plateau.[Chinese Medical Equipment Journal,2025,46(4):29-34]

Epidural spinal cord stimulation (eSCS) represents an emerging neuromodulation technology that ameliorates motor dysfunction in patients with spinal cord injury, Parkinson's disease, and stroke by activating sensory afferent fibers, enhancing spinal cord neural network integration, optimizing brain-spinal cord information transmission, and inducing neural plasticity. This article reviews the mechanism, electrode implantation, and stimulation parameter of eSCS, and application of eSCS in spinal cord injury, Parkinson's disease, and stroke, aiming to provide valuable insight for its clinical implementation.

Objective:To investigate the clinicopathological and molecular genetic characteristics of pediatric tumors with DICER1 mutations.Methods:A total of 90 patients diagnosed with various types of pediatric tumors at Beijing Children′s Hospital, Capital Medical University, Beijing, China from July 2023 to September 2025 were included in this study. PCR amplification and Sanger sequencing were performed to detect the coding-region mutations of the DICER1 gene. The clinical, histopathological, and molecular genetic features of the cases with DICER1 mutation were then analyzed.Results:Among the 90 patients, 39 were male and 51 were female, with an age of onset ranging from 1 month to 17 years [median 7.13 (2.77, 10.37) years]. DICER1 mutations were detected in 37 patients (37/90, 41.1%). Among them, 9 cases harbored one mutation [6 pleuropulmonary blastomas (PPBs), 2 sex cord stromal tumors (SCSTs), and 1 cystic nephroma (CN)], 27 cases carried two mutations [10 PPBs, 3 anaplastic sarcomas of the kidney (ASKs), 3 SCSTs, 3 thyroid adenoma, 2 nodular thyroid goiters, 2 thyroid follicular lesions, 2 CN, 1 embryonal rhabdomyosarcoma, and 1 case with multiple primary tumors], and 1 case exhibited three mutations (bilateral ASKs). Despite variations in the site of origin, DICER1-mutant tumors shared several morphological features. Grossly, they presented as multilocular cystic, cystic-solid to solid masses. Microscopically, they exhibited a subepithelial layer of mesenchymal cells, with focal rhabdomyoblastic/chondroid/chondrosarcomatous differentiation, as well as cellular anaplasia. Germline testing using peripheral blood in the 31 patients with DICER1 mutation confirmed germline origin in 61.3% (19/31) of them. Parental analysis ( n=12) demonstrated genetic inheritance in 8 cases, predominantly from families with tumor history. Germline variants scattered throughout DICER1 and consisted of loss-of-function mutations (nonsense, frameshift, and splice-site). Somatic mutations showed distinct clustering in exons 24 and 25 hotspots (codons 1705, 1709, 1809, 1810 and 1813), primarily missense variants. Notably, one multiple primary tumor case harbored a somatic mosaic p.E1705K mutation. Conclusions:DICER1 mutations are frequently detected in pediatric PPB, CN, SCST, ASK, nodular thyroid goiter, thyroid adenoma, and genitourinary rhabdomyosarcoma, which often represent as the index case of DICER1 syndrome. Performing DICER1 mutation testing in these patients not only facilitates tumor diagnosis and secondary cancer surveillance, but also enables the comprehensive genetic risk assessment and management for patient′s family members.

Objective:To investigate a new method for rapid detection of the MYOD1 L122R mutation and to analyze the clinical and pathological characteristics of mutation-positive rhabdomyosarcoma.Methods:A MYOD1 mutation detection kit was developed using allele-specific Taqman fluorescence probe technology. A total of 80 rhabdomyosarcoma samples diagnosed at Beijing Children′s Hospital, Capital Medical University from June 2022 to June 2023 were collected for testing. The detection sensitivity, specificity, and consistency rate of the kit were compared with those of the gold standard Sanger sequencing. The demographic, histopathological, and molecular genetic characteristics of patients with MYOD1 mutations were analyzed.Results:Among the 80 rhabdomyosarcoma cases, there were 46 males and 34 females, with an age of onset ranging from 0 to 16 years [mean (6.0±4.4) years], including 32 embryonal rhabdomyosarcoma, 18 alveolar rhabdomyosarcoma, and 30 spindle cell/sclerosing rhabdomyosarcoma. The new kit screened a total of 11 mutations, of which 10 were spindle cell/sclerosing rhabdomyosarcoma and one was embryonal rhabdomyosarcoma. Patients with MYOD1 mutations were typically older (four cases over 10 years old) but could also occur in young children (the youngest being 3-year and 2-month-old). The primary sites were the head and neck region in eight cases, limbs in two cases, and pelvic cavity in one case. Among the six patients with available staging information at initial diagnosis, one was classified as stage 2 and five were stage 3, all of which were intermediate risk. Among the 11 mutation patients, six had recurrence and metastasis, with three deaths; the remaining patients had not shown tumor progression until last follow-up. Compared with the wild type group, the expression level of MYOD1 in mutation patients increased significantly ( χ2=10.66, P=0.01), while the event-free survival rate ( χ2=9.925, P<0.01) and overall survival ( χ2=4.53, P=0.03) rate decreased. Compared with Sanger sequencing, the kit achieved 100% sensitivity and specificity. The kit had a minimum mutation content detection limit of 2% and the reaction could be finished within 2 hours. Additionally, this kit might also be used to detect the expression of MYOD1, thereby aiding the diagnosis of rhabdomyosarcoma. Conclusions:The study has established a new method for accurate and rapid detection of MYOD1 mutation in rhabdomyosarcoma, particularly suitable for the formalin-fixed and paraffin-embedded samples in clinical settings. MYOD1 mutations more likely occur in spindle cell/sclerosing rhabdomyosarcoma of the head and neck region in children. Patients with MYOD1 mutations have an extremely poor prognosis, which is independent of clinical staging and grading. MYOD1 mutation detection in rhabdomyosarcoma has significant value for auxiliary diagnosis and prognostic assessment.

Objective:To investigate the efficacy of antiviral therapy and influencing factors of hepatitis B surface antigen(HBsAg) negative conversion for hepatitis B e antigen(HBeAg)-positive chronic hepatitis B(CHB) in children.Methods:The clinical data of 38 children with CHB who received antiviral treatment in Children's Hospital Affiliated to Xi'an Jiaotong University from January 2019 to August 2024 were collected.All patients were treated with interferon alpha monotherapy or combined with nucleoside analogues for 48 weeks.The patients were divided into HBsAg negative group and HBsAg non-negative group according to the therapeutic results at 48 weeks.Multivariate Logistic regression were used to identify influencing factors of HBsAg negative conversion at 48 weeks.The receiver operator characteristic（ROC）curve was used to analyze the predictive value of each factor to HBsAg negative conversion.Results:The alanine aminotransferase normalization rate，hepatitis B virus DNA negative rate，HBeAg negative rate and HBsAg negative rate were 76.3%，94.7%，39.5% and 47.4%，respectively at 48 weeks.There were 18 cases in HBsAg negative group and 20 cases in HBsAg non-negative group.There were statistical significant differences in age and HBsAg decline level at 12 and 24 weeks of antiviral treatment between HBsAg negative group and HBsAg non-negative group（ P<0.05）.Multivariate Logistic regression analysis showed that age and HBsAg decline level at 12 and 24 weeks of antiviral treatment were independent predictors of HBsAg negative conversion at 48 weeks（ OR=0.664，95% CI 0.473-0.932， P=0.018； OR=8.719，95% CI 1.920-39.604， P=0.005； OR=6.182，95% CI 2.083-18.347， P=0.001）.The area under the curve of age and HBsAg decline level at 12 and 24 weeks were 0.737（95% CI 0.576-0.899， P=0.012），0.847（95% CI 0.725-0.969， P<0.001）and 0.939（95% CI 0.811-0.991， P<0.001），respectively.When the age was less than 4.625 years，the sensitivity，specificity，positive predictive value and negative predictive value of HBsAg negative conversion at 48 weeks were 83.3%，65.0%，68.2% and 81.3%，respectively.A decrease in HBsAg level of >1.07 lg IU/mL at 12 weeks of treatment had a sensitivity，specificity，positive predictive value，and negative predictive value of 72.2%，90.0%，86.7%，and 78.3%，respectively，for predicting HBsAg seroclearance at 48 weeks.A reduction in HBsAg of >1.92 lg IU/mL at 24 weeks of treatment showed a sensitivity，specificity，positive predictive value，and negative predictive value of 83.3%，90.0%，88.2%，and 85.7%，respectively，in predicting HBsAg seroclearance at 48 weeks. Conclusion:The children with CHB have a higher rate of HBsAg negative conversion after antiviral therapy at 48 weeks.Age and HBsAg decline level at 12 and 24 weeks of antiviral treatment can serve as early predictors for HBsAg negative conversion in children with CHB.