BACKGROUND:Recent research indicates that disc degeneration is closely related to abnormal stress load,and mechanotransduction proteins play a key role in it. OBJECTIVE:To investigate the role and mechanism of mechanotransduction proteins in the mechanotransduction process induced by abnormal mechanical stimulation in disc degeneration,and to summarize the current treatment strategies targeting mechanotransduction to delay intervertebral disc degeneration. METHODS:Using"intervertebral disc,nucleus pulposus,annulus fibrosus,cartilaginous endplate,cell,mechanics,signal transduction,protein,biomechanics"as Chinese search terms,and"intervertebral disc,nucleus pulposus,annulus fibrosus,cartilaginous endplate,cell,mechanical stimulation,signal transduction,protein,biomechanics"as English search terms,relevant literature in the PubMed and CNKI databases was searched.A total of 88 articles were ultimately included for review. RESULTS AND CONCLUSION:Disc cells can sense external mechanical stimulation through various mechanotransduction proteins and convert it into biological responses within the cells.These transduction proteins mainly include collagen proteins in the extracellular matrix,cell membrane surface receptors(such as integrins and ion channels),and cytoskeleton structural proteins.Their regulation of mechanotransduction processes primarily involves the activation of multiple pathways,such as the PI3K/AKT signaling pathway,nuclear factor-kB signaling pathway,and Ca2+/Calpain2/Caspase3 pathway.Mechanotransduction proteins play a key role in the mechanotransduction of disc cells.Abnormal expression of these proteins or resulting changes in the extracellular matrix environment can disrupt the mechanical balance of disc cells,leading to disc degeneration.In-depth study of the expression and regulatory mechanisms of mechanotransduction proteins in disc cells,and identification of key pathological links and therapeutic targets,is of significant importance for developing treatment strategies for disc degeneration.Current strategies to delay intervertebral disc degeneration by targeting mechanotransduction mainly include regulation of transduction proteins and improvement of the extracellular matrix.However,research in this area is still in its early stages.As research continues,new breakthroughs are expected in the regulation of disc degeneration by mechanotransduction proteins.

BACKGROUND:Traditional surgery for lumbar disc herniation involves extensive excision of tissue surrounding the nerve for decompression and removal of protruding lumbar intervertebral discs,which poses various risks and complications such as nerve damage causing paralysis,lumbar instability,herniation recurrence,intervertebral space infection,and adjacent vertebral diseases. OBJECTIVE:To propose the symmetrically adduction of lumbar decompression induced resorption of herniated nucleus pulpous technique for lumbar spine symmetrically decompression,showing the induced resorption of herniated nucleus pulpous phenomenon and early clinical efficacy,and then analyze its decompression mechanism. METHODS:214 patients with lumbar disc herniation at Department of Orthopedics,First Affiliated Hospital of Zhengzhou University from March 2021 to May 2023 were enrolled in this study.Among them,81 patients received conservative treatment as the control group,and 133 patients received symmetrically adduction of lumbar decompression induced resorption of herniated nucleus pulpous treatment as the trial group.Before surgery,immediately after surgery(7-14 days),and early after surgery(over 1 year),MRI images were used to measure the volume changes of lumbar disc herniation.CT images were used to measure the posterior displacement distance of the lumbar spinous process ligament complex,as well as the width and height of the lateral recess.Japanese Orthopaedic Association scores were used to evaluate the patient's neurological function recovery. RESULTS AND CONCLUSION:(1)Control group:81 patients with lumbar disc herniation were treated conservatively,with a total of 171 herniated lumbar discs.The average follow-up time was(22.7±23.1)months.The first and second MRI measurements of 171 herniated lumbar discs showed herniated lumbar disc volumes of(551.6±257.9)mm3 and(792.2±330.4)mm3,respectively,with an average volume increase rate of(53.2±44.4)%,showing statistically significant differences(P<0.001).Out of 171 herniated lumbar discs,4 experienced natural shrinkage,with an absorption ratio of 2.3%(4/171)and an absorption rate of(24.5±9.9)%.(2)Trial group:133 patients with lumbar disc herniation had a total of 285 herniated lumbar discs.(1)Immediately after surgery:All patients were followed up immediately after surgery.229 out of 285 herniated lumbar discs experienced retraction,with an absorption ratio of 80.3%(229/285)and an average absorption rate of(21.5±20.9)%,with significant and complete absorption accounting for 6.5%.There were a total of 70 herniated lumbar discs in the upper lumbar spine,with an absorption ratio of 85.7%(60/70),an average absorption rate of(23.1±19.5)%,and a maximum absorption rate of 86.6%.There were 215 herniated lumbar discs in the lower lumbar spine,with an absorption ratio of 78.6%(169/215),an average absorption rate of(21.0±21.3)%,and a maximum absorption rate of 83.2%.Significant and complete absorption of the upper and lower lumbar vertebrae accounted for 5.7%and 6.5%,respectively,with no statistically significant difference(P>0.05).The average distance of posterior displacement of the spinous process ligament complex immediately after surgery was(5.2±2.8)mm.There were no significant differences in the width and height of the left and right lateral recess before and immediately after surgery(P>0.05).The Japanese Orthopaedic Association score immediately after surgery increased from(10.1±3.4)before surgery to(17.0±4.8),and the immediate effective rate after surgery reached 95.6%.(2)Early postoperative period:Among them,46 patients completed the early postoperative follow-up.There were 101 herniated lumbar discs,with an absorption ratio of 94%(95/101)and an average absorption rate of(36.9±23.7)%.Significant and complete absorption accounted for 30.6%,with a maximum absorption rate of 100%.Out of 101 herniated lumbar discs,3 remained unchanged in volume,with a volume invariance rate of 2.97%(3/101).Out of 101 herniated lumbar discs,3 had an increased volume of herniated lumbar discs,with an increase ratio of 2.97%(3/101)and an increase rate of(18.5±18.4)%.The Japanese Orthopaedic Association score increased from preoperative(9.3±5.1)to(23.5±4.0),with an excellent and good rate of 93.4%.(3)The early postoperative lumbar disc herniation absorption ratios of the control group and trial group were 2.3%and 85.9%,respectively,with statistically significant differences(P<0.001).(4)Complications:There were two cases of incision exudation and delayed healing in the trial group.After conservative treatment such as dressing change,no nerve injury or death occurred in the incision healing,and no cases underwent a second surgery.(5)It is concluded that symmetrically adduction of lumbar decompression induced resorption of herniated nucleus pulpous is a new method for treating lumbar disc herniation that can avoid extensive excision of the"ring"nerve and achieve satisfactory early clinical efficacy.It does not damage the lumbar facet joints or alter the basic anatomical structure of the lateral recess,fully preserves the herniated lumbar discs,and can induce significant or even complete induced resorption of herniated nucleus pulpous.Symmetrically adduction of lumbar decompression induced resorption of herniated nucleus pulpous provides a new basis and method for the clinical treatment of lumbar disc herniation.

Primary hepatic cancer is one of the major problems that need to be solved urgently in the field of public health, seriously endangering the life and health of Chinese people. Its treatment mode is multidisciplinary participation and synergy of multiple therapeutic methods. Even though there are many common clinical treatments for liver cancer in China, its therapeutic outcome is still unsatisfactory. yttrium-90 has been applied for more than 20 years, and a large amount of foreign clinical data have been accumulated. Combining the latest literature and clinical practice, the authors describe the clinical application and research progress of yttrium-90 micro-sphere selective internal radiation therapy in primary liver cancer.

Objective To explore the effects of different fractionation doses,fractionation methods,and other related parameters on the peripheral blood lymphocyte count of patients with liver cancer receiving CyberKnife radiotherapy.Methods The clinical data of 90 patients with liver cancer receiving CyberKnife radiotherapy in our hospital were retrospectively analyzed.The peripheral blood lymphocyte counts of patients 1 week before CyberKnife radiotherapy and 1 week,1 month and 3 months after treatment were determined.The effects of different prescribed doses,fractionation doses and numbers of fractionations on the peripheral blood lymphocyte count were analyzed.Results The peripheral blood lymphocyte counts of patients with different prescribed doses,fractionation doses and fractionation methods after CyberKnife treatment decreased to varying degrees compared with those 1 week before treatment(P<0.05).The peripheral blood lymphocyte counts of patients in the groups with≤5 fractionations and fractionation dose>7 Gy were significantly higher than those of patients in the groups with>5 fractionations and the fractionation dose≤7 Gy,respectively(P<0.05).There was no significant difference in peripheral blood lymphocyte counts between patients with different prescribed doses before and after CyberKnife treatment(P>0.05).Conclusion CyberKnife in the treatment of liver cancer with≤5 ractionations and a fractionation dose of>7 Gy is more beneficial to alleviate the decrease of lymphocyte count caused by Cyberknife treatment.

Objective:To provide references for the application of finite element model in the study of cervical vertebra by statistically analysing the frequency, numerical value, properties, and boundary setting of the finite element model and the corresponding material features as well as boundary settings in the literature.Methods:The literature on cervical vertebra-related finite element models was collected from CNKI, Wanfang, VIP, PubMed, Web of Science, and Embase databases from January 2013 to December 2023. The quality assessment was followed by manual screening. The data sources, application classification, material properties (Young’s modulus and Poisson’s ratio), and boundary conditions of cervical vertebra, cervical intervertebral, and cervical ligaments were statistically analyzed.Results:A total of 102 papers were included. The finite element models of the cervical vertebra were derived from medical image reconstruction modeling techniques, predominantly CT plain scan and magnetic resonance imaging. Among the 102 cervical vertebra models, the C3-C7 (lower cervical segment) model appeared with the highest frequency (19). The Young’s modulus of the cortical bone, cancellous bone, and posterior structure of cervical vertebrae were set at about 12 000 or 10 000, 440, and 3 600 MPa, respectively, and the Poisson’s ratios were mainly set at about 0.29 or 0.30, 0.29, and 0.29. The Young’s modulus of the cervical intervertebral disc endplate, nucleus pulposus, and annulus fibrosus were concentrated around 500 or 2 000, 1, and 100 MPa, respectively, and the Poisson’s ratios were set at about 0.40, 0.50, and 0.40, respectively. The Young’s modulus of the anterior longitudinal ligament, posterior longitudinal ligament, transverse ligament, ligamentum flavum, interspinous ligament, capsular ligament, and articular cartilage of the cervical spine were set around 30, 20, 20, 6-10, 4-8, 10 or 20, 10 MPa, and the Poisson’s ratios were set at aoubt 0.30, 0.30, 0.30, 0.30, 0.30, 0.40, and 0.30, respectively. The Young’s modulus of the upper cervical interdental ligament, lamina, cruciate ligament, nuchal ligament, and pterygoid ligament were set at about 10, 10, 10 or 20, 20, and 5 MPa, respectively, and the Poisson’s ratios were set at about 0.30. Head weight settings were more common at 50, 74, and 100 N.Conclusions:The finite element model of the cervical vertebra has great value in the study of cervical spondylosis, but further optimization is still needed in the assignment of material properties, mesh division, and model verification to improve the accuracy and clinical applicability of the model.

The limitations of traditional image reconstruction algorithms of electrical impedance tomography(EIT)and the advantages of deep learning in nonlinear image reconstruction were introduced.The research progress of three EIT image reconstruction algorithms based on deep learning was summarized,including direct reconstruction method,indirect recon-struction method and implicit reconstruction method.The deficiencies of EIT image reconstruction algorithms based on deep learning were analyzed,and it's pointed out that EIT image reconstruction algorithms based on deep learning should realize further technical breakthroughs in increasing the quality of datasets,enhancing the image interpretability and improving the imaging resolving power.[Chinese Medical Equipment Journal,2024,45(4):98-103]

Objective To study the ability of radial basis function neural network(RBFNN)with different implementations for electrical impedance tomography(EIT)under real brain shapes,to evaluate the advantages and disadvantages of different approaches,and to provide a reference for the selection of practical imaging methods.Methods COMSOL Multiphysics was used to establish a multilayer 2D model with real structure based on brain CT and an EIT simulation dataset.The effects of the exact RBFNN,the orthogonal least squares-based RBFNN(OLS RBFNN)and the K-Means-based BRFNN(K-Means RBFNN)on the image reconstruction result were explored with the dataset constructed.The root mean square error(RMSE)and image correlation coefficient(ICC)were adopted to evaluate the imaging results.Results EIT could be completed with all the three RBFNNs without noise,and the exact RBFNN had the best results with average ICC and RMSE of 0.784 and 0.467,respectively,in the test set.The OLS RBFNN had the best imaging results at a hidden node of 50,with an average ICC and RMSE of 0.788 and 0.462,respectively.The K-Means RBFNN achieved the best imaging results at noise levels of 30,40,50,60,70 and 80 dB with stable ICC and RMSE and high robustness.Conclusion All the three RBFNNs can be used for brain EIT image reconstruction with their own advantages and disadvantages,and the RBFNN has to be selected for EIT reconstruc-tion based on considerations on actual conditions.[Chinese Medical Equipment Journal,2024,45(10):1-6]

Objective To explore clinical outcomes and bone resection of interlaminar fenestration decompression and u-nilateral biportal endoscopic(UBE)technique in treating lumbar disc herniation(LDH).Methods A retrospective study was performed on 105 patients with single-level LDH treated from December 2019 to December 2021.Fifty-four patients in UBE group,including 32 males and 22 females,aged from 18 to 50 years old with an average of(38.7±9.3)years old,were treated with UBE,29 patients withL4.5and 25 patients with L5S1.There were 51 patients in small fenestration group,including 27 males and 24 females,aged from 18 to 50 years old with an average of(39.9±10.0)years old,were treated with small fenestra-tion,25 patients with L4.5 and 26 patients with L5S1.Perioperative indexes,such as operation time,postoperative time of getting out of bed and hospital stay were observed and compared between two groups.Visual analogue scale(VAS)and Oswestry dis-ability index(ODI)were compared between two groups before operation and 1,3,6 and 12 months after operation,respective-ly;and modified MacNab evaluation criteria was used to evaluate clinical efficacy.Amount of bone resection and retention rate of inferior articular process laminoid complex were compared between two groups.Results All 105 patients were successfully completed operation.Both of two groups were followed up from 6 to 12 months with an average of(10.69±2.49)months.Oper-ation time,postoperative time of getting out of bed and hospital stay were(58.20±5.54)min,(2.40±0.57)dand(3.80±0.61)d in UBE group,and(62.90±7.14)min,(4.40±0.64)d and(4.40±0.64)d in small fenestrum group,respectively;and had sta-tistically difference between two groups(P＜0.05).Postoperative VAS of low back and leg pain and ODI in both groups were significantly lower than those before surgery(P＜0.05).VAS of lumbar pain in UBE group(1.37±0.49)score was lower than that of small fenestration group(2.45±0.64)score,and had statistically difference(t=9.745,P＜0.05).Postoperative ODI in UBE group at 1 and 3 months were(28.54±3.31)％and(22.87±3.23)％,respectively,which were lower than those in small fenestra group(36.31±9.08)％and(29.90±8.36)％,and the difference was statistically significant(P＜0.05).There were no significant difference in VAS and ODI between two groups at other time points(P＞0.05).According to the modified MacNab evaluation criteria at the latest follow-up,49 patients got excellent result,3 good,and 2 fair in UBE group.In small fenestration group,35 patients got excellent,12 good,and 4 fair.In UBE group,amount of bone resection on L4,5 segment was(0.45±0.08)cm3 and(0.31±0.08)cm3 on the segment of L5S1.In small fenestration group,amount of bone resection on L4.5 segment was(0.57±0.07)cm3 and(0.49±0.04)cm3 on the segment of L5S1,and amount of bone resection of lower articular process laminar complex on the same segment in UBE group was less than that in small fenestration group(P＜0.05).In UBE group,retention rate of laminoid complex on L4,5 segment was(0.73±0.04)and L5S1 segment was(0.83±0.03),whileL4,5segment was(0.68± 0.06)and L5S1 segment was(0.74±0.04)in small fenestration group,the lower articular process laminar complex retention rate in UBE group was higher than that in small fenestration group(P＜0.05).Conclusion Both unilateral double-channel endoscopy and small fenestration of laminae could achieve good clinical results in treating LDH,but UBE has advantages of less trauma,higher eficiency,faster postoperative recovery and less damage to bone structure.

Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in tertiary hospitals in major regions of China in 2022.Methods Clinical isolates from 58 hospitals in China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems.Results were interpreted using the 2022 Clinical &Laboratory Standards Institute(CLSI)breakpoints.Results A total of 318 013 clinical isolates were collected from January 1,2022 to December 31,2022,of which 29.5％were gram-positive and 70.5％were gram-negative.The prevalence of methicillin-resistant strains in Staphylococcus aureus,Staphylococcus epidermidis and other coagulase-negative Staphylococcus species(excluding Staphylococcus pseudintermedius and Staphylococcus schleiferi)was 28.3％,76.7％and 77.9％,respectively.Overall,94.0％of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 90.8％of MRSE strains were susceptible to rifampicin.No vancomycin-resistant strains were found.Enterococcus faecalis showed significantly lower resistance rates to most antimicrobial agents tested than Enterococcus faecium.A few vancomycin-resistant strains were identified in both E.faecalis and E.faecium.The prevalence of penicillin-susceptible Streptococcus pneumoniae was 94.2％in the isolates from children and 95.7％in the isolates from adults.The resistance rate to carbapenems was lower than 13.1％in most Enterobacterales species except for Klebsiella,21.7％-23.1％of which were resistant to carbapenems.Most Enterobacterales isolates were highly susceptible to tigecycline,colistin and polymyxin B,with resistance rates ranging from 0.1％to 13.3％.The prevalence of meropenem-resistant strains decreased from 23.5％in 2019 to 18.0％in 2022 in Pseudomonas aeruginosa,and decreased from 79.0％in 2019 to 72.5％in 2022 in Acinetobacter baumannii.Conclusions The resistance of clinical isolates to the commonly used antimicrobial agents is still increasing in tertiary hospitals.However,the prevalence of important carbapenem-resistant organisms such as carbapenem-resistant K.pneumoniae,P.aeruginosa,and A.baumannii showed a downward trend in recent years.This finding suggests that the strategy of combining antimicrobial resistance surveillance with multidisciplinary concerted action works well in curbing the spread of resistant bacteria.

Objective To investigate the distribution and antimicrobial resistance profiles of the common pathogens isolated from urine from 2015 to 2021 in the CHINET Antimicrobial Resistance Surveillance Program.Methods The bacterial strains were isolated from urine and identified routinely in 51 hospitals across China in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Antimicrobial susceptibility was determined by Kirby-Bauer method,automatic microbiological analysis system and E-test according to the unified protocol.Results A total of 261 893 nonduplicate strains were isolated from urine specimen from 2015 to 2021,of which gram-positive bacteria accounted for 23.8％(62 219/261 893),and gram-negative bacteria 76.2％(199 674/261 893).The most common species were E.coli(46.7％),E.faecium(10.4％),K.pneumoniae(9.8％),E.faecalis(8.7％),P.mirabilis(3.5％),P.aeruginosa(3.4％),SS.agalactiae(2.6％),and E.cloacae(2.1％).The strains were more frequently isolated from inpatients versus outpatients and emergency patients,from females versus males,and from adults versus children.The prevalence of ESBLs-producing strains in E.coli,K.pneumoniae and P.mirabilis was 53.2％,52.8％and 37.0％,respectively.The prevalence of carbapenem-resistant strains in E.coli,K.pneumoniae,P.aeruginosa and A.baumannii was 1.7％,18.5％,16.4％,and 40.3％,respectively.Lower than 10％of the E.faecalis isolates were resistant to ampicillin,nitrofurantoin,linezolid,vancomycin,teicoplanin and fosfomycin.More than 90％of the E.faecium isolates were ressitant to ampicillin,levofloxacin and erythromycin.The percentage of strains resistant to vancomycin,linezolid or teicoplanin was＜2％.The E.coli,K.pneumoniae,P.aeruginosa and A.baumannii strains isolated from ICU inpatients showed significantly higher resistance rates than the corresponding strains isolated from outpatients and non-ICU inpatients.Conclusions E.coli,Enterococcus and K.pneumoniae are the most common pathogens in urinary tract infection.The bacterial species and antimicrobial resistance of urinary isolates vary with different populations.More attention should be paid to antimicrobial resistance surveillance and reduce the irrational use of antimicrobial agents.