ObjectiveThe rapid advancement of bioanalytical technologies has heightened the demand for high-throughput, label-free, and real-time cellular analysis. Electrochemical impedance spectroscopy (EIS) operating in the GHz frequency range (GHz-EIS) has emerged as a promising tool for characterizing cell suspensions due to its ability to rapidly and non-invasively capture the dielectric properties of cells and their microenvironment. Although GHz-EIS enables rapid and label-free detection of cell suspensions, significant challenges remain in interpreting GHz impedance data for complex samples, limiting the broader application of this technique in cellular research. To address these challenges, this study presents a novel method that integrates GHz-EIS with deep learning algorithms, aiming to improve the precision of cell suspension concentration identification and quantification. This method provides a more efficient and accurate solution for the analysis of GHz impedance data. MethodsThe proposed method comprises two key components: dielectric property dataset construction and backpropagation (BP) neural network modeling. Yeast cell suspensions at varying concentrations were prepared and separately introduced into a coaxial sensor for impedance measurement. The dielectric properties of these suspensions were extracted using a GHz-EIS dielectric property extraction method applied to the measured impedance data. A dielectric properties dataset incorporating concentration labels was subsequently established and divided into training and testing subsets. A BP neural network model employing specific activation functions (ReLU and Leaky ReLU) was then designed. The model was trained and tested using the constructed dataset, and optimal model parameters were obtained through this process. This BP neural network enables automated extraction and analytical processing of dielectric properties, facilitating precise recognition of cell suspension concentrations through data-driven training. ResultsThrough comparative analysis with conventional centrifugal methods, the recognized concentration values of cell suspensions showed high consistency, with relative errors consistently below 5%. Notably, high-concentration samples exhibited even smaller deviations, further validating the precision and reliability of the proposed methodology. To benchmark the recognition performance against different algorithms, two typical approaches—support vector machines (SVM) and K-nearest neighbor (KNN)—were selected for comparison. The proposed method demonstrated superior performance in quantifying cell concentrations. Specifically, the BP neural network achieved a mean absolute percentage error (MAPE) of 2.06% and an R² value of 0.997 across the entire concentration range, demonstrating both high predictive accuracy and excellent model fit. ConclusionThis study demonstrates that the proposed method enables accurate and rapid determination of unknown sample concentrations. By combining GHz-EIS with BP neural network algorithms, efficient identification of cell concentrations is achieved, laying the foundation for the development of a convenient online cell analysis platform and showing significant application prospects. Compared to typical recognition approaches, the proposed method exhibits superior capabilities in recognizing cell suspension concentrations. Furthermore, this methodology not only accelerates research in cell biology and precision medicine but also paves the way for future EIS biosensors capable of intelligent, adaptive analysis in dynamic biological research.

Ferroptosis has received great attention as an iron-dependent programmed cell death for efficient cancer therapy. However, with the accumulation of iron in tumor cells, the antioxidant system is activated by reducing glutathione (GSH) with glutathione peroxidase 4 (GPX4), which critically limits the ferroptosis therapeutic effect. Herein, an iron and GPX4 silencing siRNA (siGPX4) co-encapsulated ferritin nanocage (HFn@Fe/siGPX4) was developed to enhance ferroptosis by disruption of redox homeostasis and inhibition of antioxidant enzyme synergistically. The siGPX4 were loaded into the nanocages by pre-incubated with iron, which could significantly improve the loading efficiency of the gene drugs when compared with the reported gene drug loading strategy by ferritin nanocages. And more iron was overloaded into the ferritin through the diffusion method. When HFn@Fe/siGPX4 was taken up by human breast cancer cell MCF-7 in a TfR1-mediated pathway, the excess iron ions in the drug delivery system could for one thing induce ferroptosis by the production of reactive oxygen species (ROS), for another promote siGPX4 escaping from the lysosome to exert gene silencing effect more effectively. Both the in vitro and in vivo results demonstrated that HFn@Fe/siGPX4 could significantly inhibit tumor growth by synergistical ferroptosis. Thus, the developed HFn@Fe/siGPX4 afforded a combined ferroptosis strategy for ferroptosis-based antitumor as well as a novel and efficient gene drug delivery system.

Objective To design an exhalation valve reservior cup to solve the problems of removal of the condensate and prevention of aerosol diffusion.Methods The reservior cup was composed of a temporary storage bottle,a liquid collection bottle,a sealing mechanism and a connection mechanism.The temporary storage bottle was connected to the exhalation valve of the ventilator at the upper end,which was provided with an internal holding chamber for temporary storage of the condensate and a through hole at the bottom for connection to the outside.The mouth of the liquid collection bottle could be inserted into the through hole,and there are a number of side holes on the mouth.The sealing mechanism at the bottom of the temporary storage bottle was made up of a magnet and a magnetic sealing plate,of which,the magnet was on the bottom surface of the holding chamber and the magnetic sealing plate was adsorbed to the magnet to seal the through hole.The connection mechanism between the temporary storage bottle and the liquid collection bottle consisted of an annular sleeve,an internal thread and an external thread.Results The reservior cup facilitated timely elimination of the condensate in the ventilator pipeline without removing the access cover,maintaining mechanical ventilation during drainage for the ventilator-assisted therapy and minimizing the risk of aerosol diffusion in the operating area.Conclusion The reservoir cup with high convenience and safety eliminates the condensate quickly and shortens the retention time of bacteria in the ventilator pipeline effectively.[Chinese Medical Equipment Journal,2024,45(9):115-117]

Objective:To investigate the influence of changes in the cognitive load of anesthesia residents on the teaching effectiveness of high-fidelity scenario simulation.Methods:Eighty-seven anesthesia residents in a grade-A tertiary hospital from February to November 2022 were divided into groups A, B, and C according to the random number method. Three cases were selected from the anesthesia crisis resource teaching case library for high-fidelity simulation training for the three groups, respectively, using the crossover design to control the order of the cases. Each round of training consisted of pre-training instruction, simulation teaching, and post-training summarization and analysis. After three rounds of simulation teaching, cognitive load, anxiety status, test scores, and non-technical skills were evaluated for all the study participants. SPSS 20.0 was used to perform analysis of variance with repeated measures and Pearson's correlation analysis.Results:All the three groups showed significantly higher cognitive load and anxiety scores during the first-round simulation training than during the second-round and third-round simulation trianing. The test scores were significantly lower in the first round [(87.07±5.66), (88.38±5.41), (89.07±6.17)] than in the second round [(95.69±2.29), (96.10±2.08), (96.07±2.60)] and the third round [(96.34±1.45), (96.38±1.50), (96.17±1.73); all P<0.05]. The non-technical skill scores were also significantly lower in the first round [(37.24±7.58), (38.69±7.27), (39.24±8.74)] than in the second round [(46.17±5.55), (47.07±5.59), (47.59±6.74)] and the third round [(47.17±5.21), (48.48±5.38), (48.24±6.83); all P<0.05]. For simulations with the same cases, the trainees showed significantly higher cognitive load and anxiety scores and significantly lower test scores and non-technical skill scores in the first round than in the second and third rounds ( P<0.05). Conclusions:Anesthesia residents have higher levels of cognitive load and anxiety in the first scenario simulation training, which can reduce learning outcomes, and repeated simulation training can reduce trainees' cognitive load and anxiety.

Objective To explore planning effect of AI-HIP assisted surgical planning system in primary unilateral total hip arthroplasty(THA)and its influence on clinical outcomes.Methods A retrospective analysis was conducted on clinical data of 36 patients who underwent their first unilateral THA from March 2022 to November 2022 and continuously used AI-HIP system(AI-HIP group),including 16 males and 20 females,aged from 43 to 81 years old with an average of(62.2±10.9)years old.According to the matching principle,36 patients who were planned by the traditional template method at the same period were selected as the control group,including 16 males and 20 females,aged from 40 to 80 years old with an average of(60.9±12.1)years old.The accuracy between two groups of prostheses were compared,as well as the combined eccentricity difference between preoperative planning and postoperative practice,lower limb length difference,osteotomy height from the upper edge of the lesser trochanter and top shoulder distance to evaluate planning effect.Harris score and visual analogue scale(VAS)were used to evaluate clinical efficacy.Results Both groups were followed up for 12 to 18 months with an average of(14.5±2.1)months.The complete accuracy and approximate accuracy of acetabular cup and femoral stalk prosthesis in AI-HIP group were 72.2％,100％,58.3％,88.9％,respectively,which were better than 44.4％,83.3％,33.3％,66.7％in control group(P＜0.05).There was no statistical significance in planning of femoral head prosthesis size(P＞0.05).The actual combined eccentricity difference and combined eccentricity difference(practical-planning)in Al-HIP group were 1.0(0.2,2.4)mm and 1.1(-2.1,3.2)mm,respectively;which were better than 3.0(1.4,4.9)mm and 3.5(-1.6,6.5)mm in control group(P＜0.05).There was no significant difference between two groups in actual osteotomy height of the upper margin of the lesser trochanter(P＞0.05).In AI-HIP group,the actual difference of lower extremity length after surgery,the difference of lower extremity length(practical-planning),osteotomy height from the upper margin of lesser trochanter(practical-planning),actual topshoulder distance after surgery,and topshoulder distance(practical-planning)were 1.5(0.2,2.8),1.1(-0.3,2.2),2.1(-2.3,4.1),(15.3±4.1),2.2(-4.8,0.3)mm,respectively;which were better than control group of 2.6(1.3,4.1),2.5(0.3,3.8),5.8(-2.4,7.7),(13.0±4.3),-5.7(-9.4,-2.2)mm(P＜0.05).At final follow-up,there were no significant differences in Harris scores of pain,function,deformity,total scores and VAS between two groups(P＞0.05).The range of motion score was 4.8±0.6 in AI-HIP group,which was higher than that in control group(4.4±0.8)(P＜0.05).Conclusion Compared with traditional template planning,AI-HIP assisted surgical planning system has good accuracy in predicting the prosthetic size of the acetabular cup and femoral stalk,restor-ing joint eccentricity,planning lower limb length,osteotomy height and top shoulder distance on the first unilateral THA,and the clinical follow-up effect is satisfactory.

Objective To propose a multi-cascade deep learning processor-based surgical instrument detection and pose estimation algorithm to facilitate the robotic scurb nurse to recognize and delivery surgical instruments.Methods The proposed multi-cascade deep leaning processor-based CYSP algorithm was hibernated with several functional modules such as YOLOX with coordinate attention block(CA-YOLOX),segment anything model(SAM)and principal component analysis(PCA).Firstly,CA-YOLOX was applied to identifying the types of the surgical instruments and completing the coarse positioning of x and y coordinates;secondly,the SAM segmenter was used to clarify the positions of the instruments in the RGB image,and the depth information and internal parameters of the camera were introduced to obtain the point cloud of the surgical instruments;finally,the center of mass,principal direction and normal direction of the surgical instrument point cloud were determined through the PCA algorithm,with which the rotation and translation(RT)matrix between the target coordinate system(surgical instrument center of mass coordinate system)and the base coordinate system of the robotic arm was solved,and the matrix was converted into a quaternion and then transmitted to the robotic arm control unit so as to drive the robotic arm to arrive at the corresponding position and pick up the instrument to complete the instrument delivery task.Migration training was accomplished on a self-constructed surgical instrument image dataset and the effectiveness of the proposed algorithm was evaluated,and instrument delivery experiments were performed on a seven-degree-of-freedom robotic arm and the success rate of the algorithm was assessed.Results The multi-cascade deep leaning processor-based CYSP algorithm had a recognition accuracy of 98.52％on the surgical instrument dataset,a success rate of 94％for the in-strument delivery experiment and average time for recognition of 0.28 s.Conclusion The multi-cascade deep leaning proces-sor-based CYSP algorithm with high reliability and practicability behaves well in facilitating the robotic scurb nurse to recog-nize and deliver surgical instruments.[Chinese Medical Equipment Journal,2024,45(6):1-8]

In this experiment, the PK/PD fitting model of Chuanxiong(Chuanxiong Rhizoma) in the treatment of rheumatoid arthritis was established in the form of acupoint combined with external application gel paste. Firstly, the rheumatoid arthritis model was induced by ovalbumin, and the articular fluid of rabbits was extracted by microdialysis. The pharmacokinetic process of Chuanxiong in rabbit articular fluid was analyzed by UPLC-MS/MS, and the pharmacokinetic model was established. The pharmacodynamic effects of Chuanxiong on inflammatory factors IL-1β, TNF-α, and IL-6 were analyzed by enzyme-linked immunosorbent assay(ELISA). The pharmacodynamic model was established, and the PK/PD model was obtained by fitting the data of pharmacokinetics and pharmacodynamics. The results of pharmacokinetics showed that the concentration of ligustrolide A in the articular cavity by drug administration on classical acupoint Zusanli(ST 36) was higher than that by Yanglingquan(GB 34), which reflected the advantage of typical acupoint, while ligustrazine concentration was higher after administration through Yanglingquan than through Zusanli, which was different from the traditional acupoint theory. The results of pharmacodynamics showed that the drug had lag effect. The PK/PD model was constructed by fitting the data. When IL-1β was taken as the efficacy index, the PK/PD models of Chuanxiong in typical acupoint Zusanli group, atypical acupoint Yanglingquan group, and non-acupoint group were E=115.28C_e/(3 316.72+C_e), E=108.73C_e/(2 993.47+C_e), and E=101.34C_e/(3 028.51+C_e). When TNF-α was taken as the efficacy index, the PK/PD models of Chuanxiong in typical acupoint Zusanli group, atypical acupoint Yanglingquan group, and non-acupoint group were E=68.31C_e/(3 285.16+C_e), E=59.27C_e/(2 919.86+C_e), and E=53.61C_e/(2 862.87+C_e). When IL-6 was taken as the efficacy index, the PK/PD models of Chuanxiong in typical acupoint Zusanli group, atypical acupoint Yanglingquan group, and non-acupoint group were E=59.92C_e/(3 461.17+C_e), E=58.34C_e/(2 723.51+C_e), and E=49.17C_e/(2 862.76+C_e). The parameters showed that there were significant differences in E_(max), EC_(e50) and k_(eo). The analysis of data found that the PK/PD fitting effect of Zusanli, a typical acupoint, was the best, which proved that it was still the best site for drug administration. To sum up, it shows that there may be bidirectional selectivity between drugs and acupoints.
Animals ; Rabbits ; Tumor Necrosis Factor-alpha ; Chromatography, Liquid ; Interleukin-6 ; Tandem Mass Spectrometry ; Acupuncture Points ; Arthritis, Rheumatoid/drug therapy*

METTL3 and METTL14 are two components that form the core heterodimer of the main RNA m6A methyltransferase complex (MTC) that installs m6A. Surprisingly, depletion of METTL3 or METTL14 displayed distinct effects on stemness maintenance of mouse embryonic stem cell (mESC). While comparable global hypo-methylation in RNA m6A was observed in Mettl3 or Mettl14 knockout mESCs, respectively. Mettl14 knockout led to a globally decreased nascent RNA synthesis, whereas Mettl3 depletion resulted in transcription upregulation, suggesting that METTL14 might possess an m6A-independent role in gene regulation. We found that METTL14 colocalizes with the repressive H3K27me3 modification. Mechanistically, METTL14, but not METTL3, binds H3K27me3 and recruits KDM6B to induce H3K27me3 demethylation independent of METTL3. Depletion of METTL14 thus led to a global increase in H3K27me3 level along with a global gene suppression. The effects of METTL14 on regulation of H3K27me3 is essential for the transition from self-renewal to differentiation of mESCs. This work reveals a regulatory mechanism on heterochromatin by METTL14 in a manner distinct from METTL3 and independently of m6A, and critically impacts transcriptional regulation, stemness maintenance, and differentiation of mESCs.
Animals ; Mice ; Methylation ; Chromatin ; Histones/metabolism* ; RNA, Messenger/genetics* ; Methyltransferases/metabolism* ; RNA/metabolism*

A fluorescence endoscopic laser confocal microscope(FELCM) was used to direct the injection of sinomenine solid lipid nanoparticles(Sin-SLN) into the joint, and the in vitro effectiveness of Sin-SLN in the treatment of rheumatoid arthritis(RA) was evaluated. Sin-SLN was prepared with the emulsion evaporation-low temperature curing method. The Sin-SLN prepared under the optimal conditions showed the encapsulation efficiency of 64.79%±3.12%, the drug loading of 3.84%±0.28%, the average particle size of(215.27±4.21) nm, and the Zeta potential of(-32.67±0.84) mV. Moreover, the Sin-SLN demonstrated good stability after sto-rage for 30 days. The rabbit model of RA was established by the subcutaneous injection of ovalbumin and complete Freund's adjuvant. Five groups were designed, including a control group, a model group, a Sin(1.5 mg·kg~(-1)) group, a Sin-SLN(1.5 mg·kg~(-1)) group, and a dexamethasone(positive drug, 1.0 mg·kg~(-1), ig) group. The control group and the model group only received puncture treatment without drug injection. After drug administration, the local skin temperature and knee joint diameter were monitored every day. The knee joint diameter and the local skin temperature were lower in the drug administration groups than in the model group(P<0.05, P<0.01). FELCM recorded the morphological alterations of the cartilage of knee joint. The Sin-SLN group showed compact tissue structure and smooth surface of the cartilage. Enzyme-linked immunosorbent assay(ELISA) was employed to determine the serum le-vels of interleukin-1(IL-1) and tumor necrosis factor-α(TNF-α). The findings revealed that the Sin-SLN group had lower IL-1 and TNF-α levels than the model group(P<0.05, P<0.01). Hematoxylin-eosin(HE) staining was employed to reveal the pathological changes of the synovial tissue, which were significantly mitigated in the Sin-SLN group. The prepared Sin-SLN had uniform particle size and high stability. Through joint injection administration, a drug reservoir was formed. Sin-SLN effectively alleviate joint swelling and cartilage damage of rabbit, down-regulated the expression of inflammatory cytokines, and inhibited the epithelial proliferation and inflammatory cell infiltration of the synovial tissue, demonstrating the efficacy in treating RA.
Animals ; Rabbits ; Tumor Necrosis Factor-alpha ; Fluorescence ; Arthritis, Rheumatoid/drug therapy* ; Interleukin-1 ; Arthritis, Experimental/drug therapy*

OBJECTIVE: To explore the effect of Xuebijing injection on inflammation in sepsis by regulating intestinal microbiota and its metabolites. METHODS: A total of 45 male Sprague-Dawley (SD) rats were randomly divided into Sham operation group (Sham group), cecal ligation and perforation (CLP) induced sepsis group (CLP group), and Xuebijing intervention group (XBJ group, 4 mL/kg Xuebijing injection was injected intraperitoneally at 1 hour after CLP), with 15 rats in each group. The survival of rats was observed at 24 hours after operation and sacrificed. Feces were collected for 16S rRNA gene sequencing and liquid chromatography-mass spectrometry (LC-MS) analysis. RESULTS: At 24 hours after operation, all rats in the Sham group survived, the mortality of rats in the XBJ group was lower than that in the CLP group [47% (7/15) vs. 60% (9/15), P > 0.05]. Compared with the Sham group, the diversity of gut microbiota in the CLP group decreased, the dominant flora changed, and the abundance of inflammation-related flora increased. Xuebijing improved the changes in gut microbiota caused by sepsis, and α diversity showed an increasing trend (Ace index: 406.0±22.5 vs. 363.2±38.2, Chao1 index: 409.7±21.8 vs. 362.4±42.5, both P > 0.05). Restrictive constrained principal coordinate analysis (cPCoA) showed a high similarity in gut microbiota among the same group of rats. The CLP group was dominated by Bacteroidetes, while the Sham and XBJ groups were dominated by Firmicutes. In addition, compared with the CLP group, Xuebijing treatment increased the abundance of beneficial bacteria in septic rats, such as Verrucomicrobia, Akkermansia and Lactobacillus. LC-MS and orthogonal partial least squares discriminant analysis (OPLS-DA) showed that there were 12 main differential metabolites among the three groups, and there were certain correlations between these metabolites, which were related to amino acid and lipid metabolism. Correlation analysis showed a significant correlation between changes in metabolites and microbial communities. CONCLUSIONS Xuebijing can improve the survival rate of septic rats, regulate the composition of intestinal flora and related metabolites, which provides a new pathophysiological mechanism for Xuebijing in the treatment of sepsis.
Rats ; Male ; Animals ; Rats, Sprague-Dawley ; Gastrointestinal Microbiome ; RNA, Ribosomal, 16S ; Sepsis/metabolism* ; Inflammation