Objective To design an experimental device for simulating the interface micro motion of bone trabecular prosthesis and carry out the finite element analysis.Methods The experimental device was composed of a screw-in cylinder with threads,a flexible hinge,a micro-motion rod,a trabecular prosthesis,a connecting rod and a fixation post.A model of the experimental device was constructed with SolidWorks software,and then imported into ABAQUS software to establish a finite element model.An axial displacement load was applied to the femur to analyze the effects of the position of the flexible hinge,the gap between the prosthesis and the femur and the length of the connecting rod on the micro motion.Results The interface micro motion produced by the experimental device increased with the distance of the flexible hinge from the lower end of the screwed-in cylinder;the gap between the prosthesis and the femur did not affect the interface micro motion when the gap was not lower than 20 μm;the interface micro motion rose with the length of the connecting rod.Conclusion The experimental device can accurately simulate the micro motion of different bone trabecular prosthesis interfaces,and can be used for studying the effect of the interface micro motion on osseointegration.[Chinese Medical Equipment Journal,2024,45(1):25-30]

Objective To study the pharmacokinetic characteristics of the test formulation of compound lidocaine cream and reference formulation of lidocaine and prilocaine cream in Chinese healthy subjects and to evaluate whether there is bioequivalence between the two formulations.Methods A single-center,single-dose,randomized,open-label,two-period,two-sequence,crossover design was used.This study included 40 healthy subjects,and in each period,test formulation or reference formulation 60 g was applied to the skin in front of both thighs(200 cm2 each side,a total of 400 cm2)under fasting conditions,and the drug was left on for at least 5 h after application.The concentrations of lidocaine and prilocaine in plasma were determined using liquid chromatography-tandem mass spectrometry(LC-MS/MS)method.Pharmacokinetic parameters were calculated using WinNonlin 8.0 software to evaluate the bioequivalence of the two formulations.Results After the application of the test formulation compound lidocaine cream and the reference formulation lidocaine and prilocaine cream on both thighs of the subjects,the pharmacokinetic parameters of lidocaine in plasma were as follows:Cmax were(167.27±91.33)and(156.13±66.86)ng·mL-1,AUC0-t were(1 651.78±685.09)and(1 636.69±617.23)ng·mL-1·h,AUC0-∞ were(1 669.85±684.65)and(1 654.37±618.30)ng·mL-1·h,the adjusted geometric mean ratios were 104.49％,101.88％and 101.89％,respectively,with 90％confidence intervals of 98.18％-111.20％,97.80％-106.13％and 97.87％-106.07％,all within the range of 80.00％-125.00％.The pharmacokinetic parameters of prilocaine in plasma were as follows:Cmax were(95.66±48.84)and(87.52±39.16)ng·mL-1,AUC0-t were(790.86±263.99)and(774.14±256.42)ng·mL-1·h,AUC0_m were(807.27±264.67)and(792.84±254.06)ng·mL-1 h,the adjusted geometric mean ratios were 107.34％,103.55％and 102.98％,respectively with 90％confidence intervals of 101.69％-113.31％,99.94％-107.30％and 99.65％-106.43％,all within the range of 80.00％-125.00％.Conclusion The test formulation compound lidocaine cream and the reference formulation lidocaine and prilocaine cream are bioequivalent.

Objective To analyze the stresses in implanted titanium solid and bone trabecular prosthesis hip replacements.Methods A femur model was built inversely based on Mimics software,and optimized using Geomagic software,and then materialized by SolidWorks software.The osteotomized femur was assembled with the metal femoral stem to form a model,and then the model was imported into ABAQUS for finite element calculation.The upper femur was divided into four regions in different states of integration:medial proximal point(small trochanter region),lateral proximal region(large trochanter region),proximal point of the femoral stem(region around the mid-portion of the styloid process)and distal region(around the end of the styloid process and distal portion).Calculations were carried out over the femoral stresses before and after implantation of titanium solid and trabecular prostheses under gait and stair-climbing loads and the interfacial stresses when the region was unintegrated.The type of deformation at the bone interface was analyzed by means of a stress ellipsoid.Results At the small trochanter region,the stress shielding rates of the trabecular prosthesis under gait and stair climbing loads were reduced by 20.5％and 14.7％compared to the titanium solid prosthesis,respectively.In case of different integration states of the titanium solid prosthesis,the interface tensile stresses under the gait and stair climbing loads were up to 10.842 MPa and 12.900 MPa,and the shear stresses reached 7.050 MPa and 6.805 MPa,respectively;in case of different integration states of the trabecular prosthesis,the interface tensile stresses under the gait and stair climbing loads were up to 3.858 MPa and 4.389 MPa,and the shear stresses reached 4.156 MPa and 3.854 MPa,respectively.Under the 2 different loads,the inboard shear stress ellipsoid of the interface opened toward the sides and the bone interface showed tensile deformation;the outboard shear stress ellipsoid of the interface opened up and down and had compressive deformation.Conclusion After total hip arthroplasty,the overall performance of the trabecular prosthesis is better than that of the titanium solid prosthesis.The unintegrated edges of the prosthesis-bone interface are susceptible to stress concentrations and distortion which may result in occurrence of failures.[Chinese Medical Equipment Journal,2024,45(3):29-35]

Objective To explore the mechanical behavior of cancellous bone under the interaction of whole-body low-magnitude high-frequency vibration(LMHFV)parameters,in order to provide theoretical guidance for the clinical treatment of disuse osteoporosis.Methods A three-dimensional reconstruction model was established for the cancellous bone of the mid femur by Mimics software,which was then imported into Comsol software to form a three-dimensional fluid-solid coupling finite element model.Twelve scenarios with the vibration acceleration amplitude(a)being 0.015×g,0.02×g,0.03×g and vibration frequency(f)being 30,45,60 and 100 Hz were set up for the simulation study to analyze the distribution rules of the hydrodynamic microenvironment,the stresses and the deformation displacements of cancellous bone under the interaction of LMHFV parameters.Results The bone marrow flow velocity on the surface of trabeculae and deformation displacement of bone matrix increased with the rising of a and decreased with the growing of f.Trabeculae gained high mean values of deformation displacement in case of the vibration scenario(0.015×g/0.02×g/0.03×g,30 Hz),and had high von Mises stress when LMHFV parameters were restricted within(0.02×g to 0.03×g,30 Hz to 35 Hz).Conclusion Whole-body LMHFV significantly improves the force and hydrodynamic environment of cancellous bone,and force-mediated osteoblast bioactivity can be enhanced by rationally modulating LMHFV parameters during clinical processes so as to promote osteogenesis.[Chinese Medical Equipment Journal,2024,45(7):17-23]

Objective:To evaluate early residual myocardial ischemia after successful percutaneous coronary intervention (PCI) in patients with coronary artery disease by using myocardial perfusion imaging (MPI) and investigate independent influencing factors of early residual myocardial ischemia.Methods:From January 2020 to December 2022, 127 patients (107 males, 20 females; age (60.3±9.6) years) with coronary artery disease who underwent PCI complete revascularization at the First People′s Hospital of Changzhou were consecutively enrolled prospectively. All patients underwent rest and stress MPI within 1-3 months after PCI. Reversible myocardial perfusion defect in the blood supply area of the culprit vessels in stress and rest MPI was defined as early residual myocardial ischemia after PCI. Accordingly, the culprit vessels undergoing PCI were divided into residual ischemic group and non-ischemic group. Differences of cardiovascular examination between two groups were compared ( χ2 test), such as proportion of culprit vessels with severe stenosis (≥90%), proportion of bifurcation lesions, and proportion of diffuse coronary disease. Logistic regression analyses were performed to identify influencing factors for early residual myocardial ischemia. Results:Among 148 culprit vessels undergoing PCI in 127 patients, early residual myocardial ischemia was present in 49 vessels (33.1%, 49/148). The proportion of culprit vessels with severe stenosis before PCI in residual ischemia group was higher than that in non-ischemia group (69.4%(34/49) and 49.5%(49/99); χ2=5.27, P=0.022). The proportion of bifurcation lesions in residual ischemic group was also higher than that in non-ischemic group (28.6%(14/49) and 10.1%(10/99); χ2=8.23, P=0.004), with a slightly higher proportion of diffuse coronary disease compared to non-ischemic group (14.3%(7/49) and 4.0%(4/99); χ2=3.62, P=0.057). Multivariate logistic regression analysis showed that bifurcation lesion (odds ratio ( OR)=4.087, 95% CI: 1.615-10.344, P=0.003) and diffuse coronary disease ( OR=4.208, 95% CI: 1.115-15.878, P=0.034) were independent influencing factors for early residual myocardial ischemia. Conclusions:Early residual myocardial ischemia is still present in about 1/3 of the culprit vessels after PCI complete revascularization. Bifurcation lesion and diffuse coronary disease are independent influencing factors for early residual myocardial ischemia in culprit vessels.

Protein-based plant immune inducers are special compounds that can induce plant defense re-sponses.They are mainly derived from pathogenic microorganisms,biocontrol microorganisms,host plants,and host-pathogen interaction processes.Protein elicitors improve plant resistance by triggering plant pathogen-associated molecular patterns to trigger immunity and effectors to trigger immune responses that frequently involve reactive oxygen species,Ca2+,salicylic acid,jasmonic acid,gibberellin,and eth-ylene cascade signaling pathways.They can bolster plant resistance against bacterial,fungal,and viral diseases,as well as environmental stress.Here we summarize the sources,mechanisms of action,and current applications of protein-based elicitors,identify existing problems,and outline future development trends.We propose that future research should focus on improving the persistence and stability of these elicitors,exploring the combined use of multiple elicitors or their combination with other agents,and their application in plant breeding.,aiming for developing green biopesticides using protein-based elicitors.

Objective:To explore the application value of reticulocyte hemoglobin equivalent(Ret-He)for diagnosing latent iron deficiency in female plateletpheresis donors.Methods:A total of 230 female plateletpheresis donors in Fujian Blood Center from January to February 2022 were selected as the research group and divided into three groups:normal group,iron depletion(ID)group and iron deficient erythropoiesis(IDE)group,according to the severity of iron deficiency.The level of hemoglobin(HGB),mean corpuscular volume(MCV),mean corpuscular hemoglobin(MCH),coefficient of variation of red cell distribution width(RDW-CV)and Ret-He were measured by using the Sysmex XN automated hematology analyzer.Chemiluminescence immunoassay was used to detect iron biochemical indexes.Receiver operating characteristic(ROC)curve analysis was performed to evaluate the diagnosic value of relevant indicators in female blood donors with latent iron deficiency.Results:Ret-He in ID group was 32.55(31.15,33.10)pg,which was significantly lower than that in the normal group[33.80(32.73,34.70)pg](P＜0.05),and significantly higher than that in IDE group[30.40(28.70,31.50)pg](P＜0.05).ROC analysis in diagnosis of IDE demonstrated that the area under the curves(AUCs)of HGB,MCV,MCH,RDW-CV and Ret-He were 0.892,0.843,0.909,0.890,0.931,respectively.When the critical value of Ret-He was 32.05 pg,its sensitivity and specificity were 85.90％and 92.60％,respectively.However,all red blood cell parameters had poor diagnostic value for ID.Conclusion:Ret-He is a perfect predictor for latent iron deficiency in female blood donors.Detection of Ret-He can advance the diagnosis of iron deficiency in female blood donors to the IDE stage.

Aim To study the active ingredients and mechanism of action of Xinkeshu tablets against myo-cardial ischemia by network pharmacology and ze-brafish model.Methods The anti-myocardial ische-mia activity of Xinkeshu tablets was evaluated by iso-prenaline hydrochloride(ISO)-induced zebrafish myo-cardial ischemia model and H2O2-induced H9c2 dam-age model.The active ingredients of Xinkeshu tablets were retrieved using databases such as TCMSP.The potential targets were predicted by PharmaMapper data-base.Myocardial ischemic disease targets were searched by OMIM database.The potential therapeutic targets of Xinkeshu tablets against myocardial ischemia were analyzed.GO and KEGG enrichment analysis were conducted on core targets.The active ingredients were verified by zebrafish and cell model.qRT-PCR was used to detect the expression of key targets.Re-sults Xinkeshu tablets could significantly alleviate ISO-induced pericardial edema and bradycardia.It al-so could increase sinus venous-bulb aortic(SV-BA)distance and improve the cell viability.The 30 poten-tial active ingredients of Xinkeshu tables mainly acted on 30 core targets,including ALB,AKT1 and MAPK1,to regulate 627 GO items,including protein phosphorylation,negative regulation of apoptosis and positive regulation of PI3K signal transduction.KEGG results showed that 117 signaling pathways,including PI3K/Akt,FOXO and Ras,exerted anti-myocardial ischemia effect.Salvianolic acid A,lithospermic acid,rosmarinic acid,salvianolic acid D,salvianolic acid B,ginsenoside Rg2,hyperoside,3'-methoxypuerarin,3'-hydroxypuerarin and ginsenoside Rg1 could alleviate ISO-induced zebrafish myocardial ischemia and im-prove the cell viability.Xinkeshu tablets could upregu-late the expression of genes such as ras and akt1,and downregulate the expression of genes such as mapk1 and mapk8.Conclusion The active ingredients,in-cluding salvianolic acid A in Xinkeshu tablets,exert anti-myocardial ischemia effects by targeting targets,such as AKT1,MAPK1,and regulating signaling path-ways,such as PI3K/Akt,MAPK and Ras.

Norepinephrine (NE) modulates synaptic transmission and long-term plasticity through distinct subtype adrenergic receptor (AR)-mediated-intracellular signaling cascades. However, the role of NE modulates glutamatergic long-term potentiation (LTP) in the hypothalamic paraventricular nucleus (PVN) magnocellular neuroendocrine cells (MNCs) is unclear. We here investigate the effect of NE on high frequency stimulation (HFS)-induced glutamatergic LTP in rat hypothalamic PVN MNCs in vitro, by whole-cell patch-clamp recording, biocytin staining and pharmacological methods. Delivery of HFS induced glutamatergic LTP with a decrease in N2/N1 ratio in the PVN MNCs, which was enhanced by application of NE (100 nM).HFS-induced LTP was abolished by the blockade of N-methyl-D-aspartate receptors (NMDAR) with D-APV, but it was rescued by the application of NE. NE failed to rescue HFS-induced LTP of MNCs in the presence of a selective β1-AR antagonist, CGP 20712. However, application of β1-AR agonist, dobutamine HCl rescued HFS-induced LTP of MNCs in the absence of NMDAR activity. In the absence of NMDAR activity, NE failed to rescue HFS-induced MNC LTP when protein kinase A (PKA) was inhibited by extracellular applying KT5720 or intracellular administration of PKI. These results indicate that NE activates β1-AR and triggers HFS to induce a novel glutamatergic LTP of hypothalamic PVN NMCs via the postsynaptic PKA signaling pathway in vitro in rats.

Norepinephrine (NE) modulates synaptic transmission and long-term plasticity through distinct subtype adrenergic receptor (AR)-mediated-intracellular signaling cascades. However, the role of NE modulates glutamatergic long-term potentiation (LTP) in the hypothalamic paraventricular nucleus (PVN) magnocellular neuroendocrine cells (MNCs) is unclear. We here investigate the effect of NE on high frequency stimulation (HFS)-induced glutamatergic LTP in rat hypothalamic PVN MNCs in vitro, by whole-cell patch-clamp recording, biocytin staining and pharmacological methods. Delivery of HFS induced glutamatergic LTP with a decrease in N2/N1 ratio in the PVN MNCs, which was enhanced by application of NE (100 nM).HFS-induced LTP was abolished by the blockade of N-methyl-D-aspartate receptors (NMDAR) with D-APV, but it was rescued by the application of NE. NE failed to rescue HFS-induced LTP of MNCs in the presence of a selective β1-AR antagonist, CGP 20712. However, application of β1-AR agonist, dobutamine HCl rescued HFS-induced LTP of MNCs in the absence of NMDAR activity. In the absence of NMDAR activity, NE failed to rescue HFS-induced MNC LTP when protein kinase A (PKA) was inhibited by extracellular applying KT5720 or intracellular administration of PKI. These results indicate that NE activates β1-AR and triggers HFS to induce a novel glutamatergic LTP of hypothalamic PVN NMCs via the postsynaptic PKA signaling pathway in vitro in rats.