BACKGROUND:Intertrochanteric fracture of femur has various fracture types and fixation methods,and the mechanical stability of each fixation system is quite different.It is of scientific clinical significance to use finite element analysis method to carry out biomechanical research on various fixation systems. OBJECTIVE:To compare and analyze the mechanical stability of various internal fixations applied to femoral intertrochanteric fracture A031-A2.1 by finite element method. METHODS:Based on the validated finite element model of femur(Intact),the model was cut and made into A031-A2.1 intertrochanteric fracture of femur.Different internal fixation systems were implanted by simulating clinical operation methods,and fixation models of proximal femoral nail antirotation,dynamic hip screw,percutaneous compression plate and proximal femoral locking plate were established respectively.All nodes under the distal femur of the four groups of models were constrained,and compression loads of 700,1 400 and 2 100 N were applied to the femoral head.Von Mises stress distribution and compression stiffness of each group of models were observed through calculation and analysis,and mechanical stability of each group was compared. RESULTS AND CONCLUSION:(1)Through calculation and analysis,after calculating the compression stiffness by comparing the deformation of each model,the compression stiffness of each model under various loads showed the trend:physiological group>proximal femoral nail antirotation group>proximal femoral locking plate group>percutaneous compression plate group>dynamic hip screw group.The compressive stiffness of the complete physiological group model was significantly higher than that of all surgical group models.(2)The stress index was observed.Due to the stress shielding effect,the stress peak value of each fixed group was higher than that of physiological group,and the maximum peak value was concentrated on each internal fixation.Proximal femoral nail antirotation group had the smallest stress peak,while dynamic hip screw group had the highest stress.The stress distribution trend showed physiological group

Objective To evaluate the efficacy and safety of a novel intravascular lithotripsy(IVL)balloon—Vesscrack shockwave balloon—for vascular preparation before stent implantation in patients with severe coronary artery calcification(CAC).Methods This was a prospective,single-arm,multicenter study conducted in China from June 2022 to October 2022.Patients with severe CAC were treated with the Vesscrack shockwave balloon for lesion preparation,followed by drug-eluting stent(DES)implantation.Of these,33 patients underwent optical coherence tomography(OCT).The primary endpoint was procedural success,defined as successful stent implantation with residual stenosis≤30％and the absence of in-hospital major adverse events,including cardiac death,target vessel-related myocardial infarction,or target lesion revascularization.Results A total of 170 patients[mean age:(65.9±7.9)years,116 males]were enrolled.After treatment with IVL and DES,the minimum lumen diameter increased significantly compared to baseline[(2.34±0.40)mm vs.(0.95±0.33)mm,P＜0.001],the degree of stenosis was significantly reduced[(13.24±6.60)％vs.(65.18±10.59)％,P＜0.001].Procedural success was achieved in 100％of cases,and device success was 98.8％.The 30-day patient-related cardiovascular clinical composite endpoint(POCE)rate was 0.0,with no target lesion failure,no confirmed or potential thrombotic events were observed.The shockwave energy generator demonstrated excellent stability and ease of use.Among the 33 patients assessed with OCT,after IVL intervention,the maximum calcified area of the lumen[(3.51±1.51)mm2 vs.(2.85±1.80)mm2,P＜0.001],and the minimum lumen area within the target lesion[(3.08±1.04)mm2 vs.(2.02±0.75)mm2,P＜0.001],and after DES intervention,the luminal area of the largest calcified site[(6.59±1.64)mm2 vs.(2.85±1.80)mm2,P＜0.001]and the minimum luminal area within the target lesion[(6.19±1.45)mm2 vs.(2.02±0.75)mm2,P＜0.001]were significantly increased,and the differences were statistically significant.Conclusions The Vesscrack shockwave balloon is effective and safe for vascular preparation in patients with severe CAC prior to stent implantation.It achieves significant calcified plaque modification,high procedural success rates,and minimal complications.

Objective To analyze the imaging features of cerebral small vessel disease in patients with type 2 diabetes mellitus by multimodal MRI.Methods The clinical data of 160 patients with cerebral small vessel disease admitted to our hospital from January to December 2020 were retrospectively analyzed.According to whether they were complicated with type 2 diabetes mellitus,they were divided into the diabetic group and the non-diabetic group,with 80 cases in each group.Both groups underwent multimodal MRI scans.And the severity of lacunar infarction,the severity of subcortical and periventricular white matter lesions,white matter integral and cerebral microbleeds of patients in the two groups were compared.Results The severity of lacunar infarction(χ2=34.076,P=0.001),subcortical white matter lesions(χ2=25.000,P=0.001),periventricular white matter lesions(χ2=22.895,P=0.001)and white matter integral(t=12.370,P=0.001)of patients in the diabetic group were significantly higher than those in the non-diabetic group.No cerebral microbleeds were detected in either group of patients.Conclusion Patients with cerebral small vessel disease and type 2 diabetes mellitus show characteristic multimodal MRI changes.The increase in the number of lacunar infarction lesions and the aggravation of white matter lesions can be used as the characteristic imaging basis for the diagnosis of type 2 diabetes mellitus related cerebral small vessel disease.

Objective To explore the factors affecting the enhancement quality of head and neck computed tomography angiography(CTA)images based on bolus-tracking technology,and provide a basis for quantitatively controlling image quality.Methods The general information,injection parameters,scanning parameters and analysis data of enhancement quality of images of 500 subjects who underwent head and neck CTA examinations in our hospital from January to June 2024 were prospectively collected.A comprehensive evaluation of enhancement quality of head and neck CTA images of the examinees was conducted,and the relevant examination data of the examinees with qualified and unqualified enhancement quality of images were compared.Multivariate Logistic regression analysis was used to analyze the independent factors influencing the enhancement quality of image.Results Among 500 CTA images of head and neck,262 cases had qualified enhancement quality of images and 238 cases were unqualified.There were statistically significant differences in gender,height,body weight,tube voltage,scanning direction,trigger threshold,diagnostic delay time,iodine contrast agent concentration,iodine contrast agent dosage,and iodine contrast agent flow rate between the examinees with qualified and unqualified enhancement quality of images(P<0.05).Multivariate Logistic analysis showed that the examinees were male(95%CI:0.22 to 0.75,P=0.004),body weight(95%CI:0.92 to 0.97,P<0.01),and head-foot direction scanning(95%CI:0.03 to 0.43,P=0.002),diagnostic delay time(95%CI:0.44 to 0.92,P=0.017),iodine contrast agent dosage(95%CI:1.21 to 1.34,P<0.001),iodine contrast agent flow rate(95%CI:0.14 to 0.59,P<0.001)were all the independent influencing factors of enhancement quality of image;Among them,the iodine contrast agent dosage(β=0.24,OR=1.27)was positively correlated with the enhancement quality of image,the examinees were male(β=-0.89,OR=0.41),body weight(β=-0.06,OR=0.94),head-foot direction scanning(β=-2.23,OR=0.11),diagnostic delay time(β=-0.45,OR=0.64),and iodine contrast agent flow rate(β=-1.26,OR=0.28)were negatively correlated with the enhancement quality of image.Conclusion In the application of bolus-tracking technology for head and neck CTA,individual factors,scanning parameters,and injection regimens are the key control elements that affect the positive results of enhancement quality of head and neck CTA images.In clinical practice,technicians can establish personalized scanning protocols by integrating artificial intelligence-assisted decision-making systems to achieve precise,standardized and personalized imaging.

Hepatocellular carcinoma(HCC),which is essentially primary liver cancer,is closely related to CD8+T cell immune infiltration and immune suppression.We constructed a CD8+T cells related risk score model to pre-dict the prognosis of HCC patients and provided therapeutic guidance based on the risk score.Using integrated bulk RNA sequencing(RNA-seq)and single-cell RNA sequencing(scRNA-seq)datasets,we identified stable CD8+T cell signatures.Based on these signatures,a 3-gene risk score model,comprised of KLRB1,RGS2,and TN-FRSF1B was constructed.The risk score model was well validated through an independent external validation co-hort.We divided patients into high-risk and low-risk groups according to the risk score and compared the differ-ences in immune microenvironment between these two groups.Compared with low-risk patients,high-risk patients have higher M2-type macrophage content(P＜0.0001)and lower CD8+T cells infiltration(P＜0.0001).High-risk patients predict worse response to immunotherapy treatment than low-risk patients(P＜0.01).Drug sensitivity a-nalysis shows that PI3K-β inhibitor AZD6482 and TGFβRII inhibitor SB505124 may be suitable therapies for high-risk patients,while the IGF-1R inhibitor BMS-754807 or the novel pyrimidine-based anti-tumor metabolic drug Gemcitabine could be potential therapeutic choices for low-risk patients.Moreover,expression of these 3-gene mod-el was verified by immunohistochemistry.In summary,the establishment and validation of a CD8+T cell-derived risk model can more accurately predict the prognosis of HCC patients and guide the construction of personalized treatment plans.

A pyrene-phenol-based fluorescent probe PyP which showed typical intramolecular charge transfer(ICT)and monomer-excimer activities was synthesized by using pyrene carboxaldehyde hydrazone and 4-tert-butyl-2,6-diformylphenol as the raw materials.The effects of solvents on PyP were studied,and the results showed that the color of protic polar solvents(Ethanol,N,N-dimethylformamide,methanol and H2O)were successfully identified.Based on the solvent polarity-regulated PyP monomer-excimer switching,the rapid and highly sensitive ratiometric probe,"Turn-off"and"Turn-on"multimodal probes were established for detection of trace water content in organic solvents(Dimethyl sulfoxide,N,N-dimethylformamide,ethanol and methanol),with detection limits(3σ/k)of 0.0021％,0.046％,0.062％and 0.024％.The method was successfully used to detect water content in dimethyl sulfoxide,N,N-dimethy lformamide,ethanol and methanol commercial organic solvents,with recoveries ranging from 97.2％to 108.0％.The developed method showed good accuracy and stability,and had good application prospect.

Objective:To analyze the human immunodeficiency virus (HIV) screening status and the resulting residual risk (RR) among blood donors across 17 provincial blood centers in China.Methods:This study used a cross-sectional study. Data on HIV infection markers per 100 000 first-time donors (FD) and repeat donors (RD) from January 2015 to December 2024 were extracted from the National Blood Establishment Performance Comparison Information Management System. Questionnaires were used to collect each center′s HIV screening strategy, algorithm, serological test (ST) kit manufacturers, gray-zone setting for ST, and nucleic acid test (NAT) modality, method, and platform. The incidence-window-period model was used to calculate the residual risk for first-time donors (RR FD), repeat donors (RR RD), and total donors (RR TD) at each center. Horizontal and vertical analysis of RR FD, RR RD, and RR TD across centers and years were performed. Results:All 17 centers applied the same HIV screening strategy which was two rounds of ST followed by one round of NAT. Eight of them operated a single screening algorithm, six employed two algorithms and three used three. Eleven centers used both imported and domestic ST kits, five relied on domestic ST kits only, and one used imported ST kits only, while four centers never set a grey zone for ST throughout the decade. For NAT modalities, eight centers adopted both individual nucleic acid test (ID-NAT) and minipool nucleic acid test (MP-NAT), eight used MP-NAT only and one used ID-NAT only. Seven centers combined transcription mediated amplification (TMA) and polymerase chain reaction (PCR), nine used PCR only and one used TMA only, and fourteen centers ran both imported and domestic NAT systems, two used imported systems only and one used a domestic system only. Over the ten-year period, the mean RR FD across the centers ranged from 2.22 to 12.33 per 10 6 person-years, RR RD from 0.83 to 3.29 per 10 6 person-years and RR TD from 1.59 to 9.29 per 10 6 person-years, with center Z4 consistently showing the lowest values for all three metrics and center U4 recording the highest RR FD and RR TD, while center D2 had the highest RR RD. In 2024 compared with 2015, eleven centers achieved a lower RR FD and ten centers achieved lower RR RD and RR TD. The RR FD and RR TD of centers W2 and U4 displayed pronounced fluctuations and an upward trend in recent years. Conclusions:The 17 provincial blood centers maintain consistent HIV screening strategies, while demonstrating variations in screening algorithm, ST kit manufacturers, NAT modalities, methods, and platform. And the RR FD, RR RD, and RR TD differ across centers. Although most centers show declining trend in RR over the ten-year period, some centers exhibite data fluctuations with a rising trend, suggesting potential for further optimization of HIV screening protocols.

Aim To investigate the effect of metformin on epithelial-mesenchymal transition(EMT)of lung cancer A549 cells and its underlying mechanism.Methods Lung cancer A549 cells were cultured in vitro and treated with metformin.Cell morphology was observed by fluorescence staining.The mRNA expres-sion levels of E-cadherin,N-cadherin,SMA and Vimen-tin were detected by RT-PCR.The regulatory effects of metformin on EMT in A549 cellswere examined by high-throughput sequencing.An EMT model was estab-lished through TGF-β1 induction.Following metformin treatment,the morphology of A549 cells was observed.Western blot was employed to determine the expression levels of NGF,E-cadherin,N-cadherin,SMA and Vim-entin.Additionally,si-NGF transfection was performed to evaluate the protein expressions of E-cadherin,N-cadherin,SMA and Vimentin in A549 cells,and a cell scratch assay was conducted to assess cell migration.Results After metformin treatment,A549 cells exhibi-ted a loss of mesenchymal-like morphology,character-ized by a transition to a round shape,a reduction in colony formation,and decreased adherence.RT-PCR and high-throughput sequencing revealed a down-regu-lation in the expression of genes associated with mesen-chymal transition,including N-cadherin,SMA,and Vim-entin,and an up-regulation in the expression of genes associated with epithelial transformation,such as ZO-1 and E-cadherin.Additionally,the expression of nerve growth factor(NGF)was significantly up-regulated.Following transfection with si-NGF,A549 cells treated with metformin exhibited a down-regulation in the ex-pression of the epithelial marker E-cadherin,concomi-tant with an up-regulation in the expression of stromal markers N-cadherin,Vimentin,and SMA.Conclusions Metformin can up-regulate the expression of E-cad-herin and down-regulate the expression of N-cadherin,Vimentin and SMA in lung cancer A549 cells,thereby inhibiting EMT.Additionally,NGF signaling molecules may play a significant role in this process.