Electromagnetic fields can regulate the fundamental biological processes involved in bone remodeling. As a non-invasive physical therapy, electromagnetic fields with specific parameters have demonstrated therapeutic effects on bone remodeling diseases, such as fractures and osteoporosis. Electromagnetic fields can be generated by the movement of charged particles or induced by varying currents. Based on whether the strength and direction of the electric field change over time, electromagnetic fields can be classified into static and time-varying fields. The treatment of bone remodeling diseases with static magnetic fields primarily focuses on fractures, often using magnetic splints to immobilize the fracture site while studying the effects of static magnetic fields on bone healing. However, there has been relatively little research on the prevention and treatment of osteoporosis using static magnetic fields. Pulsed electromagnetic fields, a type of time-varying field, have been widely used in clinical studies for treating fractures, osteoporosis, and non-union. However, current clinical applications are limited to low-frequency, and research on the relationship between frequency and biological effects remains insufficient. We believe that different types of electromagnetic fields acting on bone can induce various “secondary physical quantities”, such as magnetism, force, electricity, acoustics, and thermal energy, which can stimulate bone cells either individually or simultaneously. Bone cells possess specific electromagnetic properties, and in a static magnetic field, the presence of a magnetic field gradient can exert a certain magnetism on the bone tissue, leading to observable effects. In a time-varying magnetic field, the charged particles within the bone experience varying Lorentz forces, causing vibrations and generating acoustic effects. Additionally, as the frequency of the time-varying field increases, induced currents or potentials can be generated within the bone, leading to electrical effects. When the frequency and power exceed a certain threshold, electromagnetic energy can be converted into thermal energy, producing thermal effects. In summary, external electromagnetic fields with different characteristics can generate multiple physical quantities within biological tissues, such as magnetic, electric, mechanical, acoustic, and thermal effects. These physical quantities may also interact and couple with each other, stimulating the biological tissues in a combined or composite manner, thereby producing biological effects. This understanding is key to elucidating the electromagnetic mechanisms of how electromagnetic fields influence biological tissues. In the study of electromagnetic fields for bone remodeling diseases, attention should be paid to the biological effects of bone remodeling under different electromagnetic wave characteristics. This includes exploring innovative electromagnetic source technologies applicable to bone remodeling, identifying safe and effective electromagnetic field parameters, and combining basic research with technological invention to develop scientifically grounded, advanced key technologies for innovative electromagnetic treatment devices targeting bone remodeling diseases. In conclusion, electromagnetic fields and multiple physical factors have the potential to prevent and treat bone remodeling diseases, and have significant application prospects.

A novel analytical method was developed in this study by combining online solid phase extraction with ultra performance liquid chromatography-tandem mass spectrometry(Online SPE-UPLC-MS/MS)for simultaneous determination of 50 kinds of steroid hormones in surface water.Specifically,after high-speed centrifugation of 4 mL water samples,the supernatant was directly injected into an Oasis HLB online SPE column for enrichment and purification.Subsequently,the target compounds were transferred to the analytical column via valve switching for separation and analysis.The chromatographic separation was performed on a Thermo Acclaim RSLC C18 column(100 mm×2.1 mm,2.2 μm),using a mobile phase composed of 5 mmol/L ammonium fluoride aqueous solution and acetonitrile.Mass spectrometric detection was conducted in positive ion mode,utilizing multiple reaction monitoring(MRM)with quantification achieved by the internal standard method.The method validation demonstrated that the limits of detection(LOD)for the 50 kinds of steroid hormones ranged from 0.02 to 0.50 ng/L,while the limits of quantification(LOQ)were between 0.08 and 1.67 ng/L.The average recoveries in surface water samples at spiked concentrations of 5,20 and 200 ng/L were between 74.1％and 119％,with relative standard deviations(RSDs)of 0.2％to 9.9％.This method was applied to analyze 11 surface water samples collected from sites surrounding a pharmaceutical and chemical industrial park.A total of 44 kinds of steroid hormones were detected,with concentrations ranging from 0.11 to 88.6 ng/L,revealing the presence of hormone contamination in the environmental waters surrounding industrial areas.Compared with the traditional offline SPE methods,the proposed online SPE technique significantly reduced sample volume requirements and pretreatment time,while minimizing the loss of target compounds during the pretreatment process.Moreover,compared to reported online SPE techniques,this method achieved high-throughput analysis of multiple classes of steroid hormones,with lower detection limits and higher recoveries.Overall,this method provided rapid sample preparation,high sensitivity,and excellent stability,making it suitable for the direct analysis of trace steroid hormones in surface water.

In-depth study of the components of polymyxins is the key to controlling the quality of this class of antibiotics. Similarities and variations of components present significant analytical challenges. A two-dimensional (2D) liquid chromatography-mass spectrometr (LC-MS) method was established for screening and comprehensive profiling of compositions of the antibiotic colistimethate sodium (CMS). A high concentration of phosphate buffer mobile phase was used in the first-dimensional LC system to get the components well separated. For efficient and high-accuracy screening of CMS, a targeted method based on a self-constructed high resolution (HR) mass spectrum database of CMS components was established. The database was built based on the commercial MassHunter Personal Compound Database and Library (PCDL) software and its accuracy of the compound matching result was verified with six known components before being applied to genuine sample screening. On this basis, the unknown peaks in the CMS chromatograms were deduced and assigned. The molecular formula, group composition, and origins of a total of 99 compounds, of which the combined area percentage accounted for more than 95% of CMS components, were deduced by this 2D-LC-MS method combined with the MassHunter PCDL. This profiling method was highly efficient and could distinguish hundreds of components within 3 h, providing reliable results for quality control of this kind of complex drugs.

Objective To observe the effectiveness and safety of DiaSphere embolized microsphere TACE for treating primary hepatocellular carcinoma(HCC).Methods Totally 188 patients with HCC were prospectively enrolled and randomly assigned to research group(n=93)and control group(n=95),who underwent TACE with DiaSphere embolized microspheres and Embosphere embolized microspheres,respectively.The incidence of TACE-related adverse events were recorded.The therapeutic efficacy 1 month after the first TACE,also 1 and 3 months after the last TACE,and liver functions 1 month after the first and last TACE were compared between groups.Results In research group,there were 69 cases underwent 1 time TACE,22 cases underwent 2 times and 2 cases underwent 3 times TACE,while in control group,there were 82 cases underwent 1 time and 13 cases underwent 2 times TACE,respectively.No statistical difference of the incidence of adverse events was found between groups(77.42%[72/93]vs.76.84%[73/95],P=1.000).One month after the first TACE,7 cases in research group and 11 cases in control group were lost to follow-up,respectively.One month after the last TACE,12 cases were lost to follow-up in both groups,and 3 months after the last TACE,28 cases were lost to follow-up in both groups.No significant difference of objective response rate nor disease control rate was found between groups at the above time points(all P＞0.05).One month after the first and last TACE,liver function indicators were not different between groups(all P＞0.05).Conclusion Both the short-term efficacy and safety of TACE with DiaSphere embolized microspheres for treating HCC were good.

Objective To propose a low-dose CT image denoising method based on an improved Corediff model to recover the detailed features of the image and enhance the image quality.Methods An RS-Corediff model was established by modifying the key component U-Net network of the Corediff model.Firstly,the residual module was introduced in the network input stage for feature extraction;secondly,a new downsampling module was designed in the U-Net network encoder,which learned the semantic information of the feature map by convolution and maintained the learning state during the downsampling process so as to fully extract the image features;thirdly,the feature splicing processing was used to further enhance the learning effect during the upsampling process of the U-Net network decoder;finally,the convolutional kernel size was modified to adjust the sensory field during the convolutional process of the whole U-Net network structure so as to obtain rich features.The RS-Corediff model was compared with the residual encoder-decoder convolutional neural network(RED-CNN)model and the Corediff model on the public dataset AAPM 2016 in order to verify its effectiveness for low-dose CT image denoising.Results The RS-Corediff model gained advantages over the RED-CNN and Corediff models with a peak signal-to-noise ratio(PSNR)of 41.269 8,structural similarity(SSIM)of 0.953 4 and root mean square error(RMSE)of 17.568 7.Conclusion The proposed method effectively preserves the texture and details of low-dose CT images during the denoising process to improve the overall quality of the images.[Chinese Medical Equipment Journal,2025,46(5):9-13]

Objective The study aims to elucidate the inhibitory effects of curcumin on the proliferation of colon cancer RKO cells,focusing on the regulatory mechanisms of tripartite motif-containing protein 2(TRIM2)expression and the mammalian target of rapamycin(mTOR)signaling pathway.Methods Experimental concentrations of curcumin were determined by calculating the half maximal inhibitory concentration(IC50)value.Quantitative polymerase chain reaction(qPCR)was utilized to assess the level of TRIM2 expression in RKO and fetal human colon(FHC)cells.Western blotting analysis was conducted to investigate the level of TRIM2 expression and mTOR pathway-related proteins in curcumin-treated RKO cells.The impact of curcumin treatment,TRIM2-knockingdown,and mTOR signaling pathway on proliferation in RKO cells was quantified using the cell counting kit-8(CCK8)assay.Results The expression of TRIM2 was found to be elevated in RKO cells as determined by qPCR,compared to FHC cells.Curcumin suppressed the level of TRIM2 expression,and subsequent knockdown of TRIM2 resulted in decreased expression of mTOR-related proteins in RKO cells.Both curcumin and TRIM2-knockdown demonstrated significant inhibition of proliferation in RKO cells,with reversion upon activation of mTOR signaling pathway.Conclusion The study unveils the inhibitory effects of curcumin on RKO cells proliferation through modulation of TRIM2 expression and the mTOR signaling pathway.

Objective To propose a low-dose CT image denoising method based on an improved Corediff model to recover the detailed features of the image and enhance the image quality.Methods An RS-Corediff model was established by modifying the key component U-Net network of the Corediff model.Firstly,the residual module was introduced in the network input stage for feature extraction;secondly,a new downsampling module was designed in the U-Net network encoder,which learned the semantic information of the feature map by convolution and maintained the learning state during the downsampling process so as to fully extract the image features;thirdly,the feature splicing processing was used to further enhance the learning effect during the upsampling process of the U-Net network decoder;finally,the convolutional kernel size was modified to adjust the sensory field during the convolutional process of the whole U-Net network structure so as to obtain rich features.The RS-Corediff model was compared with the residual encoder-decoder convolutional neural network(RED-CNN)model and the Corediff model on the public dataset AAPM 2016 in order to verify its effectiveness for low-dose CT image denoising.Results The RS-Corediff model gained advantages over the RED-CNN and Corediff models with a peak signal-to-noise ratio(PSNR)of 41.269 8,structural similarity(SSIM)of 0.953 4 and root mean square error(RMSE)of 17.568 7.Conclusion The proposed method effectively preserves the texture and details of low-dose CT images during the denoising process to improve the overall quality of the images.[Chinese Medical Equipment Journal,2025,46(5):9-13]

Objective:To investigate the application effect of entrustable professional activities (EPAs) in competency evaluation of dermatology residents, to practice the goal of hierarchical progressive training for EPAs competency in dermatology residents, and to improve the competency of physicians.Methods:A questionnaire survey was conducted among 8 clinical instructors and 165 residents who received standardized residency training in Department of Dermatology, The First Affiliated Hospital of Jinzhou Medical University, from September 2019 to September 2022, and self-assessment and trainer-assessment were performed based on EPAs. The Kruskal-Wallis H test and the Mann-Whitney U test were used for comparison of entrustable level between the dermatology residents of different grades. Results:The scores of both trainer-assessment and self-assessment based on EPAs increased with the increase in the grade of the resident physicians, and the resident physicians of the third year (the PGY3 group) had the highest levels of trainer-assessment and self-assessment based on EPAs. The resident physicians of all grades showed relatively low assessment scores of EPA4 (making a medical decision), EPA8 (recognize a patient requiring urgent or emergent care and initiate evaluation and management), EPA14 (clinical teaching), and EPA15 (public health events management). There were significant differences in all EPAs items of trainer-assessment and self-assessment between the residents of different grades (Kruskal-Wallis test, P<0.05). There was a significant difference in trainer-assessment between PGY1 and PGY2 and between PGY1 and PGY3 (Bonferroni P correction, P<0.05), while there was no significant difference between the PGY2 and PGY3 groups ( P>0.05). Conclusions:There are differences in the evaluation of EPAs in dermatology residents of different grades, and hierarchical progressive training of EPAs competency can effectively improve the clinical competency of dermatology residents. Given the inconsistency between the scores of self-assessment and trainer-assessment, it is necessary to improve the feedback plan in the future.

Objective The study aims to elucidate the inhibitory effects of curcumin on the proliferation of colon cancer RKO cells,focusing on the regulatory mechanisms of tripartite motif-containing protein 2(TRIM2)expression and the mammalian target of rapamycin(mTOR)signaling pathway.Methods Experimental concentrations of curcumin were determined by calculating the half maximal inhibitory concentration(IC50)value.Quantitative polymerase chain reaction(qPCR)was utilized to assess the level of TRIM2 expression in RKO and fetal human colon(FHC)cells.Western blotting analysis was conducted to investigate the level of TRIM2 expression and mTOR pathway-related proteins in curcumin-treated RKO cells.The impact of curcumin treatment,TRIM2-knockingdown,and mTOR signaling pathway on proliferation in RKO cells was quantified using the cell counting kit-8(CCK8)assay.Results The expression of TRIM2 was found to be elevated in RKO cells as determined by qPCR,compared to FHC cells.Curcumin suppressed the level of TRIM2 expression,and subsequent knockdown of TRIM2 resulted in decreased expression of mTOR-related proteins in RKO cells.Both curcumin and TRIM2-knockdown demonstrated significant inhibition of proliferation in RKO cells,with reversion upon activation of mTOR signaling pathway.Conclusion The study unveils the inhibitory effects of curcumin on RKO cells proliferation through modulation of TRIM2 expression and the mTOR signaling pathway.

In-depth study of the components of polymyxins is the key to controlling the quality of this class of antibiotics.Similarities and variations of components present significant analytical challenges.A two-dimensional(2D)liquid chromatography-mass spectrometry(LC-MS)method was established for screening and comprehensive profiling of compositions of the antibiotic colistimethate sodium(CMS).A high concentration of phosphate buffer mobile phase was used in the first-dimensional LC system to get the components well separated.For efficient and high-accuracy screening of CMS,a targeted method based on a self-constructed high resolution(HR)mass spectrum database of CMS components was established.The database was built based on the commercial MassHunter Personal Compound Database and Library(PCDL)software and its accuracy of the compound matching result was verified with six known components before being applied to genuine sample screening.On this basis,the unknown peaks in the CMS chromatograms were deduced and assigned.The molecular formula,group composition,and origins of a total of 99 compounds,of which the combined area percentage accounted for more than 95％of CMS components,were deduced by this 2D-LC-MS method combined with the MassHunter PCDL.This profiling method was highly efficient and could distinguish hundreds of components within 3 h,providing reliable results for quality control of this kind of complex drugs.