BACKGROUND:Scholars at home and abroad consider New Zealand rabbits to be an ideal model animal because of the similar anatomical morphology of the lumbar spine to that of the human lumbar spine.There is a lack of systematic comparison of different ways to establish rabbit intervertebral disc degeneration models under X-ray guidance. OBJECTIVE:To establish a rabbit model of lumbar disc degeneration using X-ray guided acupuncture,end-plate injection and combined method,and to compare the modeling effects of these three methods. METHODS:Eighteen 6-month-old New Zealand white rabbits were randomly selected and divided into four groups:acupuncture group,endplate injection group,combined group and blank control group.In the acupuncture group,three consecutive segments of the intervertebral discs(L2/3,L3/4,L4/5)were needled and modeled;in the endplate injection group,50 μL of anhydrous ethanol was injected at a single point on the endplates of the three consecutive segmental discs;in the combined group,three consecutive segmental intervertebral discs were needled and injected with 50 μL of anhydrous ethanol at four azimuthal points on the endplates of the corresponding segmental discs;and the blank control group received no interventions.X-ray examination was performed to measure the disc height index at 2,4,and 8 weeks after surgery.The intervertebral disc tissues were then taken for anatomical observation and pathological examination. RESULTS AND CONCLUSION:(1)Anatomical examination showed that fibrous annulus rupture,nucleus pulposus degeneration,and total disc structure disorder were the main manifestation in the acupuncture group,endplate injection group,and combined group,respectively.(2)X-ray examination showed that the disc height index showed the most obvious reduction in the acupuncture group at 2 weeks after operation,significant reductions in the endplate injection group at 2 and 4 weeks after operation,and significant reductions in the combined group at 2,4,and 8 weeks after operation.(3)Pathological examination showed that the fibrous ring structure was damaged and the inner annulus fibrosus protruded inward in the acupuncture group;endplate fissure,disordered arrangement and nucleus loss were observed in the endplate injection group;total disc structure disorder with the nucleus pulposus losing water and shrinking and no obvious border with the broken annulus fibrosus was found in the combined group.To conclude,acupuncture,endplate injection and the modified endplate injection method can establish the rabbit intervertebral disc degeneration model.Compared with the single method,the modified endplate injection method can greatly accelerate and aggravate the degeneration of the intervertebral disc,and can effectively shorten the experiment period.

To summarize the clinical experience of Professor LIU Shangyi in treating pruritus vulvae. It is believed that women have the physiological characteristics of liver and kidney as the root， and their pubic area is easily attacked by wind-dampness pathogenic qi， so the core mechanism of pruritus vulvae is proposed as wind-dampness accumulation and deficiency of liver and kidney. The core treatment method is to dispel wind-dampness and nourish the liver and kidneys， and modify the Danggui Decoction （当归饮子） to form a self-prescribed Yinyang Formula （阴痒方） as the basic prescription to treat pruritus vulvaen.

Objective: To analyze the characteristics of injury surveillance cases among the elderly in Ningbo City, Zhejiang Province from 2014 to 2023, so as to provide the basis for formulating targeted injury intervention measures. Methods: Injury surveillance cases aged ≥60 years were collected from seven injury sentinel hospitals in Ningbo City through the Zhejiang Provincial Chronic Disease Surveillance Information Management System from 2014 to 2023. Population distribution, temporal distribution, injury circumstances, and clinical characteristics were described. Results: A total of 67 259 injury surveillance cases among the elderly were reported in Ningbo City from 2014 to 2023, including 32 159 males (47.81%) and 35 100 females (52.19%). The median age was 68.00 (interquartile range, 14.00) years. The three months with a higher number of cases were December (6 271 cases, 9.32%), August (6 226 cases, 9.26%) and October (6 221 cases, 9.25%). The primary causes of injury were falls (25 276 cases, 37.58%), stabs (12 250 cases, 18.21%), and sprains (11 815 cases, 17.57%). The injury occurred mainly in homes (44 975 cases, 66.87%) and streets/urban areas (16 174 cases, 24.05%). The predominant activities at the time of injury were leisure activities (28 801 cases, 42.82%) and household chores (23 647 cases, 35.16%). The proportions of falls as the cause of injury and injuries occurring at home among females and people aged 80 years and above were relatively high. The predominant sites of injury were upper limbs (23 354 cases, 34.72%) and lower limbs (20 343 cases, 30.25%). The predominant nature of injury were soft tissue injuries (43 345 cases, 64.44%) and bone and joint injuries (22 042 cases, 32.77%). Injuries were primarily mild and moderate in severity, with 46 391 cases (68.97%) and 20 205 cases (30.04%), respectively. The proportion of bone and joint injuries, moderate in injuries among females and people aged 80 years and above was relatively high. Conclusions The main causes of injury surveillance cases among the elderly in Ningbo City from 2014 to 2023 were falls and stabs, and the injuries occurred mainly in homes and streets/urban areas. Female and elderly people have a higher risk of injury.

Objective To investigate the effect of icotinib on right ventricular remodeling in rats with monocrotaline(MCT)-induced pulmonary hypertension(PH).Methods Sprague-Dawley rats were randomly divided into control group(0.3％sodium carboxymethyl cellulose),model group and low,high dose experimental groups(30,60 mg·kg-1 icotinib),8 rats in each group.PH rat model was established by single intraperitoneal injection of 60 mg·kg-1 MCT in model group and low,high dose experimental groups.The drug was administered continuously for 4 weeks after MCT injection.The hemodynamic indexes of each group were detected.Terminal deoxynucleotidyl transferase mediated dUTP nick end labeling(TUNEL)staining was used to detect the apoptosis of right ventricular cardiomyocytes.The protein levels of B cell lymphoma-2(Bcl-2),Bcl-2 associated X protein(Bax),cleaved cysteine aspartic acid specific protease-3(cleaved-caspase-3),epidermal growth factor receptor(EGFR),phosphorylated EGFR(p-EGFR),optic atrophy 1(Opa1)and mitofusin 2(Mfn2)were detected by Western blot analysis.Results The right ventricular systolic pressure in low,high dose experimental groups and control group,model group were(38.58±4.98),(34.15±3.88),(23.66±2.45)and(45.07±5.78)mmHg;the mean pulmonary artery pressure were(27.85±3.77),(24.25±3.09),(17.33±2.46)and(33.07±4.15)mmHg;the right ventricle(RV)to left ventricle+septum were(36.38±5.51)％,(33.63±4.69)％,(22.25±2.96)％and(42.50±7.33)％;the RV to tibial length were(69.33±7.86),(62.69±7.17),(49.12±6.42)and(78.22±9.07)mg·cm-1.There were significant differences in the above indexes between low,high dose experimental groups and model group(all P＜0.01).There were significant differences in Bcl-2,Bax,cleaved caspase-3,p-EGFR,Opa1,Mfn2 between low,high dose experimental groups and model group(P＜0.05,P＜0.01).Conclusion Icotinib can inhibit right ventricular remodeling in PH rats induced by MCT,and its mechanism may be related to reducing the phosphorylation level of EGFR in the right ventricle,alleviating mitochondrial dysfunction and inhibiting cardiomyocyte apoptosis.

Microorganisms can form biofilms, complex, heterogeneous, multicellular communities that adhere to surfaces. Biofilm formation on the surface of structures in water will accelerate structures’ corrosion, seriously affect their service efficiency and life, and significantly impact the growth of animals, plants, and human life. Hence, clarifying the mechanism of biofilm formation contributes to developing new strategies to control biofilm formation on surface and then reduce infections, biofouling, and contaminations. Biofilm-targeting strategies include the regulation of established biofilms or the modulation of single-cell attachment. In most studies, physicochemical mechanism is frequently applied to explain the initial bacterial adhesion phenomena but rarely to explain other stages of biofilm formation. This review presents a five-step comprehensive description of the physicochemical process from film formation to biofilm maturation: (1) period of film formation; (2) period of bacterial adhesion; (3) period of extracellular-polymeric-substances (EPSs) membrane formation; (4) period of regulating biofilm by quorum sensing (QS); (5) period of biofilm maturation. We first clarify how the film formed by compound molecules affects the surface’s physicochemical properties and initial adhesion, summarizing many factors that affect bacterial adhesion. We then review the types of EPSs and signal molecules secreted by bacteria after irreversible adhesion, as well as their role and QS mechanism in biofilm maturation. Finally, we discuss how bacteria or microcolonies separate from the mature biofilm by physicochemical action and summarize the morphology and adhesion characterization methods after the biofilm matures. This review redefines the role of physicochemical in the whole process of biofilm formation and provides a theoretical basis for the prevention, removal, and utilization of biofilm and other related research fields.

In recent years, nucleic acid therapy, as a revolutionary therapeutic tool, has shown great potential in the treatment of genetic diseases, infectious diseases and cancer. Lipid nanoparticles (LNPs) are currently the most advanced mRNA delivery carriers, and their emergence is an important reason for the rapid approval and use of COVID-19 mRNA vaccines and the development of mRNA therapy. Currently, mRNA therapeutics using LNP as a carrier have been widely used in protein replacement therapy, vaccines and gene editing. Conventional LNP is composed of four components: ionizable lipids, phospholipids, cholesterol, and polyethylene glycol (PEG) lipids, which can effectively load mRNA to improve the stability of mRNA and promote the delivery of mRNA to the cytoplasm. However, in the face of the complexity and diversity of clinical diseases, the structure, properties and functions of existing LNPs are too homogeneous, and the lack of targeted delivery capability may result in the risk of off-targeting. LNPs are flexibly designed and structurally stable vectors, and the adjustment of the types or proportions of their components can give them additional functions without affecting the ability of LNPs to deliver mRNAs. For example, by replacing and optimizing the basic components of LNP, introducing a fifth component, and modifying its surface, LNP can be made to have more precise targeting ability to reduce the side effects caused by treatment, or be given additional functions to synergistically enhance the efficacy of mRNA therapy to respond to the clinical demand for nucleic acid therapy. It is also possible to further improve the efficiency of LNP delivery of mRNA through machine learning-assisted LNP iteration. This review can provide a reference method for the rational design of engineered lipid nanoparticles delivering mRNA to treat diseases.

Objective: To analyze the association between latent class of health-risk behaviors and depressive symptoms among middle school students, so as to provide the evidence for the prevention and intervention of depressive symptoms among middle school students. Methods: Students in two junior high schools, two senior high schools and one vocational high school in Yinzhou District, Ningbo City, Zhejiang Province, were selected using a stratified multi-stage cluster sampling method. Demography and health-risk behaviors were collected using questionnaire surveys, depressive symptoms were investigated using the Center for Epidemiological Studies Depression-10 Scale, and latent class analysis was conducted for health-risk behaviors. The association between different latent classes and depressive symptoms was analyzed using a multivariable logistic regression model. Results: A total of 1 247 students were surveyed, including 641 boys (51.40%) and 606 girls (48.60%). There were 452 junior high school students (36.25%), 532 high school students (42.66%) and 263 vocational high school students (21.09%). Latent class analysis showed that health-risk behaviors in students were classified into three groups, namely healthy behavior group (52.93%), poor diet group (39.94%) and high-risk behavior group (7.14%), and the detection rates of depressive symptoms were 7.12%, 18.88% and 52.81%, respectively, with a statistically significant difference between groups (P<0.05). Multivariable logistic regression analysis showed that after adjusting for age, gender, native place, only child and living on campus, the poor diet group (OR=3.107, 95%CI: 2.086-4.627) and high-risk behavior group (OR=15.401, 95%CI: 9.031-26.262) had higher risks of depressive symptoms compared with the healthy behavior group. Conclusion Having high-risk behaviors and poor diet may increase the risk of developing depressive symptoms among middle school students.

BACKGROUND:In clinical application,simple interspinous fixation without additional interbody fusion has similar fixation effects to pedicle screw and rod fusion internal fixation,and can effectively reduce the range of motion of the responsible segment and the stress of the articular process.However,after simple placement of the new interspinous fusion fixation device BacFuse,the stress at the root of the spinous process is relatively concentrated,and the spinous fracture is prone to occur.If an intervertebral fusion cage is inserted in conjunction with interspinous fixation,Von Mises stress can theoretically be dispersed to reduce the risk of spinous fracture.However,there are few studies on biomechanics and finite element analysis. OBJECTIVE:To observe the biomechanical stability of interspinous fixation-assisted endoscopic interbody fusion in the treatment of severe lumbar spinal stenosis. METHODS:The normal finite element model M0 of the L4-L5 segment of the lumbar spine was established by Mimics,Geomagic,Solidworks,and ANSYS software based on the lumbar CT images of a 26-year-old adult male volunteer excluding spinal diseases.On the basis of M0,the immediate model M1 after endoscopic decompression combined with interbody fusion,the interspinous fixation device(BacFuse)model M2 after endoscopic decompression,and the interspinous fixation(BacFuse)model M3 after endoscopic-assisted interbody fusion were established.The same stress was applied to the upper surface of the L4 vertebral body in the four groups,and the lower surface of the L5 vertebral body was fixed and supported.The range of motion and the extreme Von Mises stress of the endplate bone and the posterior ligament complex of the vertebral body were analyzed under six working conditions of flexion,extension,left/right bending,and left/right rotation. RESULTS AND CONCLUSION:(1)Compared with model M0,the range of motion value of model M1 increased significantly under six working conditions.Model M2 and model M3 had a significant reduction in range of motion.(2)Compared with model M0,the maximum stress of the vertebral body in model M1 did not change significantly under the six working conditions.The maximum stress at the rear of the M2 vertebral body increased significantly.(3)Compared with model M1,the maximum stress of model M3 did not change significantly under the six working conditions.Compared with model M2,the maximum stress of model M3 decreased significantly.(4)Compared with the model M0,the extreme Von Mises stress of the L4 and L5 endplates of the model M1 was significantly increased.The extreme Von Mises stress in L4 and L5 endplates of models M2 and M3 decreased slightly.Compared with model M1,the Von Mises stress of the bone under the L4 and L5 endplate of models M2 and M3 was significantly reduced.(5)It is concluded that the implantation of BacFuse can effectively reduce the bone stress under the endplate during simple interbody fusion,decrease the risk of cage subsidence,diminish the risk of facet joint fracture on the decompression side,and provide a good stable environment for interbody fusion.The placement of an intervertebral fusion cage can reduce the stress of the root of the spinous process,which is beneficial to decrease the risk of fracture of the root of the spinous process.

Objective:To compare the efficacy of pedicle screw placement between computer navigation guidance and freehand assistance in the surgical treatment of isthmic spondylolysis at the lumbar vertebrae.Methods:A retrospective study was conducted to analyze the 47 patients with bilateral isthmic spondylolysis at the L 5 vertebra who had been treated at Department of Spinal Surgery, The General Hospital of Xinjiang Military Command from January 2020 to April 2023. All were male patients with an age of (24.0±4.3) years. They were divided into a study group (13 cases subjected to pedicle screw placement assisted by computer navigation guidance) and a control group (34 cases subjected to pedicle screw placement assisted freehandedly). The 2 groups were compared in terms of surgical incision length, intraoperative bleeding, screw placement time, postoperative hospital stay, total hospitalization cost, postoperative complications, rate of screw reposition, angle between pedicle screw and upper endplate, angle between bilateral pedicle screws, and placement accuracy; the visual analogue scale (VAS) for pain, Japanese Orthopaedic Association (JOA) score for lumbar spine function, and Oswestry disability index (ODI) were also compared between preoperation, 1-week postoperation, and the last follow-up. Patient satisfaction was assessed according to the modified MacNab criteria, and internal fixation failure and isthmic healing were also evaluated at the last follow-up. Results:There were no statistically significant differences in the preoperative general data between the 2 groups, showing comparability ( P>0.05). The differences were not statistically significant in surgical incision length, intraoperative bleeding, screw placement time, postoperative hospital stay, or postoperative complications ( P>0.05). However, in the study group, the total hospitalization cost was significantly higher than that in the control group, the rate of screw reposition [7.7% (2/26)] significantly lower than that in the study group [26.5% (18/68)], the angle between pedicle screw and upper endplate and the angle between bilateral pedicle screws were both significantly smaller than those in the control group, and the placement accuracy [92.3% (24/26)] was significantly greater than that [70.6% (48/68)] in the control group (all P<0.05). All patients were followed up for 7.0 (5.0, 14.0) months. Patients in both groups showed significant improvements in VAS, JOA score, and ODI at postoperative 1 week and the last follow-up compared with the preoperative values, and the improvements at the last follow-up were significantly larger than those at postoperative 1 week ( P<0.05). According to the modified MacNab criteria at the last follow-up, patient satisfaction was rated as excellent in 10 cases, as good in 2 cases and as moderate in 1 case in the study group while as excellent in 27 cases, as good in 3 cases, as moderate in 3 cases and as poor in 1 case in the control group. In the study group, there were 1 case of internal fixation failure, 1 case of spine cutting-out by titanium cable, and 12 cases of bony healing of the isthmus; in the control group, there were 2 cases of internal fixation failure, 2 cases of spine cutting-out by titanium cable, and 29 cases of bony healing of the isthmus. Conclusions:In the surgical treatment of bilateral isthmic spondylolysis at the L 5 vertebra, computer navigation-guided pedicle screw placement is safe and reliable, showing an advantage of higher accuracy over freehand placement. It deserves clinical promotion due to its satisfactory therapeutic effects.

Objective:To investigate the values of two-dimensional and three-dimensional echocardiographic parameters in predicting pulmonary vascular resistance (PVR) in chronic pulmonary thromboembolic pulmonary hypertension (CTEPH).Methods:A total of 141 patients diagnosed with CTEPH in China-Japan Friendship Hospital from November 2015 to December 2022 were included. Two-dimensional echocardiographic indicators reflecting PVR were constructed according to the calculation formula of PVR: echocardiographic estimated systolic pulmonary artery pressure (sPAP Echo)/left ventricular end-diastolic diameter (LVIDd), echocardiographic estimated mean pulmonary artery pressure (mPAP Echo)/LVIDd. sPAP Echo/left ventricular end-diastolic volume (LVEDV), sPAP Echo/left ventricular cardiac output (LVCO) were measured by three-dimensional echocardiography. The correlations between two-dimensional and three-dimensional echocardiographic ratios and invasive PVR were then analyzed using the Spearman correlation method. Using receiver operating characteristic curve analysis, cut-off values for the ratios were generated to identify patients with PVR>1 000 dyn·s -1·cm -5. Pre- and postoperative hemodynamics and echocardiographic data were analyzed, as well as the correlation between the reduction rate of the echocardiographic index and PVR in 54 patients who underwent pulmonary endarterectomy (PEA). Results:sPAP Echo/LVIDd, sPAP Echo/LVEDV and sPAP Echo/LVCO were moderately correlated with PVR( rs=0.62, 0.52, 0.63, both P<0.001). The ratio of sPAP Echo to LVEDV, when greater than or equal to 1.41, had a sensitivity of 0.800 and a specificity of 0.930 for determining PVR >1 000 dyn·s -1·cm -5 (AUC=0.860, P<0.001). Similarly, the ratio of sPAP Echo to LVIDd, when greater than or equal to 2.14, had a sensitivity of 0.647 and a specificity of 0.861 for determining PVR >1000 dyn·s -1·cm -5 (AUC=0.830, P<0.001). The sPAP Echo/LVIDd and mPAP Echo/LVIDd significantly decreased after PEA (both P<0.001). The sPAP Echo/LVIDd and mPAP Echo/LVIDd reduction rate (ΔsPAP Echo/LVIDd and ΔmPAP Echo/LVIDd) were significantly correlated with PVR reduction rate (ΔPVR), respectively ( rs=0.61, 0.63, both P<0.05). Conclusions:Two-dimensional ratio sPAP Echo/LVIDd and three-dimensional ratio sPAP Echo/LVEDV can be used to noninvasively estimate PVR in CTEPH patients. The conventional ratio sPAP Echo/LVIDd is convenient and reproducibly suitable for monitoring the improvement of PVR before and after treatment, and its ratio of 2.14 can predict the significant increase of PVR in CTEPH patients (>1 000 dyn·s -1·cm -5).