ObjectiveTo address the key challenges in breast electrical impedance tomography (EIT) reconstruction including the severe ill‑posedness of the inverse problem, limited measurement information from the electrodes, low contrast of small lesions, as well as the common drawbacks of traditional reconstruction methods such as boundary blurring, low spatial resolution, and weak small-target detection capability, and to overcome the limitations of existing deep learning approaches namely low training efficiency, insufficient physical consistency, and substantial information loss during the low‑to‑high dimensional mapping process, this study proposes a multi‑scale attention and dynamic sparse mask fusion network (MADS‑Net). The proposed method aims to enhance high‑resolution reconstruction accuracy, small-lesion detectability, noise robustness, and computational efficiency in breast‑screening-oriented EIT, thereby providing a feasible solution for the application of EIT in breast functional imaging. MethodsThe proposed network adopts a strategy of “locate first, reconstruct later”. It realizes adaptive allocation of computational resources through a dynamic mask module, alleviates information loss in the low-to-high dimensional mapping process via a multi-scale attention mechanism, and embeds physical constraints to improve the physical rationality of reconstruction results. The performance of the proposed method was validated through systematic numerical simulations, agar phantom experiments, and porcine tissue experiments. Comparisons were made with mainstream methods including the Gauss-Newton algorithm, convolutional neural networks, U-Net, and Deep D-Bar. The image correlation coefficient (ICC), root mean square error (RMSE), and peak signal-to-noise ratio (PSNR) were adopted as quantitative evaluation metrics. Furthermore, lesion‑level evaluation metrics were introduced to assess the capability of different methods in reconstructing abnormal target boundaries and small‑sized target regions. ResultsExperimental results demonstrate that MADS-Net outperforms all comparison methods across all test scenarios. In numerical simulations, it achieves higher accuracy in target morphology and spatial location recovery as well as better background suppression. In agar phantom experiments, its detection and imaging reliability for small targets is significantly superior to the comparison methods. In porcine tissue experiments, the model maintains good generalization performance and can adapt to complex biological tissue imaging scenarios. Quantitative results show that MADS-Net achieves an average ICC of 0.917 6±0.048 8, an RMSE as low as0.060 6±0.031 6, and a PSNR of (23.893 9±2.685 3) dB. It successfully detects tiny targets as small as 5 mm within a 100 mm diameter sensing field, reduces the total training duration by 23.5% compared with the baseline method, and maintains stable reconstruction performance even under strong noise interference. ConclusionThe results demonstrate that MADS-Net achieves favorable EIT reconstruction performance in numerical simulations, agar phantom experiments, and porcine tissue experiments, even under common practical imaging challenges including low signal-to-noise ratio and blurred tissue boundaries. This study provides a methodological reference for further research on EIT in breast-screening-related scenarios and other medical functional imaging tasks, and also offers a low-cost, radiation-free alternative for breast lesion screening that aligns with the clinical demand for non-invasive diagnostic tools. It should be noted that real clinical breast data have not yet been used for validation in this study, and the clinical applicability of the proposed method requires further investigation. Future work will prioritize collecting multi-center real clinical breast datasets, and further optimize the model’s generalization ability to adapt to individual differences in breast tissue composition to promote its clinical application.

Objective To evaluate the intravascular volume at different levels of edema and disease course by the fractional excretion of filtered sodium(FeNa)of children with primary nephrotic syndrome(PNS).Methods A total of 172 children with newly diagnosed PNS who were hospitalized in the Affiliated Hospital of Xuzhou Medical University from September 2022 to September 2024 were selected and divided into non-e-dema group(n=51),mild edema group(n=43),moderate edema group(n=46)and severe edema group(n=32)according to the degree of edema at the time of admission.A total of 40 healthy children who underwent physical examination during the same period were selected as the healthy control group.Serum creatinine,ser-um sodium were detected before and after treatment.Urine samples were collected to detect urine creatinine,urine sodium,FeNa was calculated and compared according to the results,and the degree of edema was recor-ded.24 h urine samples were collected on the same day to detect 24 h urine protein quantification and 24 h u-rine volume.Results On day 1 to 2 of the course of the disease,about 12%of the PNS children had FeNa<0.2%,indicating insufficient intravascular volume,which was mainly concentrated in the severe edema group.The moderate,severe edema group had a significantly lower FeNa level than the non-edema group,mild edema group,and healthy control group(P<0.01).The moderate edema group had a significant increase in FeNa on days 6 to 7 of the course of the disease,and the severe edema group had a significant increase in Fena on days 11 to 12 of the course of the disease(P<0.01).Conclusion Intravascular volume of PNS children with mod-erate to severe edema is often reduced,and intravascular volume may be insufficient in severe edema.PNS chil-dren with moderate to severe edema have increased intravascular volume with the extension of the course of disease and the improvement of the condition.

To investigate the molecular mechanisms underlying the mechanosensitive ion channel PI-EZO2 in osteoarthritis(OA),we developed a lentiviral vector for endogenous PIEZO2 overexpression and established a stable PIEZO2-high-expressing immortalized human primary chondrocyte line.By map-ping the open reading frame of the PIEZO2 locus and designing sequence-specific sgRNA,we employed the CRISPR/Cas9 synergistic activation mediator(SAM)system to precisely integrate transcriptional ac-tivation elements into the PIEZO2 promoter region.Lentiviral-mediated targeted genomic integration en-sured endogenous PIEZO2 overexpression,confirmed by mCherry fluorescence tracing coupled with flow cytometric sorting,which revealed membrane-specific localization of PIEZO2 protein(localization effi-ciency:78.49％).Quantitative PCR demonstrated a 17-fold upregulation of PIEZO2 mRNA,while Western blotting validated enhanced membrane-localized protein expression.Strikingly,PIEZO2-overex-pressing chondrocytes exhibited hallmark OA metabolic phenotypes compared to wild-type controls:typeⅡ collagen mRNA expression decreased to 50％of baseline levels,whereas matrix metalloproteinase 13(MMP13)mRNA surged by 20-fold.These alterations recapitulated the pathological matrix metabolic phenotype observed in biomechanical OA models induced by cyclic mechanical stress(10％strain,0.5 Hz,8 h/day for 2 consecutive days).Collectively,we successfully generated a human chondrocyte model with stable PIEZO2 overexpression,which faithfully mirrors mechanotransduction-driven OA progression.This engineered cellular system provides a robust platform for dissecting PIEZO2-mediated mechanosig-naling networks and advancing targeted therapeutic discovery.

Debates persist regarding the efficacy and safety of azvudine, particularly its real-world outcomes. This study involved patients aged ≥60 years who were admitted to 25 hospitals in mainland China with confirmed SARS-CoV-2 infection between December 1, 2022, and February 28, 2023. Efficacy outcomes were all-cause mortality during hospitalization, the proportion of patients discharged with recovery, time to nucleic acid-negative conversion (T _NANC), time to symptom improvement (T _SI), and time of hospital stay (T _HS). Safety was also assessed. Among the 5884 participants identified, 1999 received azvudine, and 1999 matched controls were included after exclusion and propensity score matching. Azvudine recipients exhibited lower all-cause mortality compared with controls in the overall population (13.3% vs. 17.1%, RR, 0.78; 95% CI, 0.67-0.90; P = 0.001) and in the severe subgroup (25.7% vs. 33.7%; RR, 0.76; 95% CI, 0.66-0.88; P < 0.001). A higher proportion of patients discharged with recovery, and a shorter T _NANC were associated with azvudine recipients, especially in the severe subgroup. The incidence of adverse events in azvudine recipients was comparable to that in the control group (2.3% vs. 1.7%, P = 0.170). In conclusion, azvudine showed efficacy and safety in older patients hospitalized with COVID-19 during the SARS-CoV-2 omicron wave in China.

Stroke is a global disease that seriously threatens human life. The pathological mechanisms of ischemic stroke include neuroinflammation, oxidative stress, and the destruction of blood vessels at the lesion site. Here, a biocompatible in situ hydrogel platform was designed to target multiple pathogenic mechanisms post-stroke, including anti-inflammation, anti-oxidant, and promotion of angiogenesis. Double-crosslinked responsive multifunctional hydrogels could quickly respond to the pathological microenvironment of the ischemic damage site and mediate the delivery of nitric oxide (NO) and ISO-1 (inhibitor of macrophage migration inhibitory factor, MIF). The hydrogel demonstrated good biocompatibility and could scavenge reactive oxygen species (ROS) and inflammatory cytokines, such as interleukin-6 (IL-6), interleukin-10 (IL-10), and MIF. In a mouse stroke model, hydrogels, when situated within the microenvironment of cerebral infarction characterized by weak acidity and elevated ROS release, would release anti-inflammatory nanoparticles rapidly that exert an anti-inflammatory effect. Concurrently, NO was sustained release to facilitate angiogenesis and provide neuroprotective effects. Neurological function was significantly improved in treated mice as assessed by the modified neurological severity score, rotarod test, and open field test. These findings indicate that the designed hydrogel held promise for sustained delivery of NO and ISO-1 to alleviate cerebral ischemic injury by responding to the brain's pathological microenvironment.

Objectives:Comparative analysis of the beagles acute-phase electrocardiographic,hemodynamic,left ventricular flow field status,and energy consumption characteristics of pacing at different sites of conduction system may help to elucidate the scientific mechanism of left bundle branch pacing(LBBP)as a option of physiological pacing therapy.Methods:Eight healthy adult beagles were used in this study.Initially,an active fixation lead was implanted in the right atrial appendage,followed by implantation of another active fixation lead at the right ventricular apex,distal His bundle,and left bundle septal branch,respectively.After connecting a dual-chamber pacemaker,electrocardiographic and acute phase hemodynamic parameters under sinus rhythm,right ventricular apex pacing(RVAP),distal His bundle pacing(DHBP),and LBBP states were collected and analyzed.Three complete cardiac cycles of standard apical three-chamber color Doppler dynamic images were acquired under vector flow mapping(VFM)mode.Offline analysis was performed on obtained parameters including isovolumic contraction period,rapid ejection period,isovolumic relaxation period,rapid filling period,atrial contraction period,and left ventricular intracavitary energy consumption.These parameters were compared under pacing at different sites and the linear correlations of major parameters were analyzed.Results:The QRS duration of baseline intrinsic sinus rhythm,RVAP,DHBP and LBBP were(45.0±4.0)ms,(98.4±6.2)ms,(50.0±4.5)ms and(62.0±4.7)ms,respectively.The LBBP-QRS duration was significantly wider than intrinsic sinus rhythm and DHBP,but significantly narrower than RVAP(all P<0.01).Compared with baseline AOO mode(the pacing rate was performed at 10 beats/min above the intrinsic heart rate),the change of acute phase maximum left ventricular pressure rise rate(LVdP/dtmax)in RVAP,DHBP and LBBP was([-7.89±5.67]% ),([0.74±2.05]% )and([-0.14±3.59]% ),respectively.There was no significant difference in LVdP/dtmax changes between DHBP and LBBP(P=0.667),but both pacing modalities were significantly better than RVAP(all P<0.01).The average energy consumption of the left ventricle under RVAP was significantly higher than that of intrinsic sinus rhythm,DHBP,and LBBP in isovolumic contraction period,rapid ejection period,isovolumic relaxation period,rapid filling period,and atrial contraction period(all P<0.01).However,there was no statistically significant difference in energy consumption among intrinsic sinus rhythm,DHBP,and LBBP during the above five phases(all P>0.05).DHBP and LBBP did not show a significant increase in the number of left ventricular vortices,vortex area,and circulation intensity compared to intrinsic sinus rhythm,and LBBP did not show a significant increase in vortex area and circulation intensity compared to DHBP.Conclusions:Although LBBP canines significantly prolonged the paced QRS duration,it showed no significant differences in acute phase left ventricular hemodynamics,left ventricular flow field status,and energy consumption compared to intrinsic sinus rhythm and DHBP.Performance of LBBP was superior to RVAP.This study may contribute to revealing the theoretical basis of LBBP as a feasible physiological pacing therapy.

Objective To explore the possibility and genetic identification method of constructing a hepatocyte-specific NLRP3 gene knockout mouse model by using Cre-LoxP system gene knockout technology.Methods Phase one:mice specifically expressing the albumin promoter-Cre(AlbCre)recombinase in hepatocytes were mated with NLRP3flox/flox mice,and the hepatocyte-specific NLRP3 gene knockout mice with the genotype of NLRP3flox/flox/AlbCre+/-(hepatocyte NLRP3 knockout group)and the control mice in the same litter with the genotype of NLRP3flox/flox/AlbCre-/-(control group in the same litter)were obtained after two generations of selection and mating.The second stage was the mass reproduction stage.Mating NLRP3flox/flox/AlbCre+/-target mice with NLRP3flox/flox mice could quickly obtain a large number of experimental target mice and control mice in the same litter.The DNA was extracted from the tails of mice after numbering,and the offspring genotype was identified by PCR.qPCR and Western blot were used to detect the mRNA and protein expression levels of NLRP3 gene in the liver tissue.HE staining was used to observe the morphological changes in liver tissues,and serum liver transaminases and inflammatory factors were detected.The changes in body weight,liver-to-body ratio and special circumstances during reproduction and development of mice in the two groups were observed.Results The offspring genotype of the target mice in the F2 generation was consistent with theoretical result of NLRP3flox/flox/AlbCre+/-.The mRNA and protein levels of NLRP3 in liver tissues of mice in the hepatocyte NLRP3 knockout group were significantly lower than those in the control group in the same litter(P<0.05).The mice in the hepatocyte NLRP3 knockout group was not affected in terms of growth,development and reproduction after the NLRP3 gene knockout.There were no statistically significant differences in the body weight,liver-to-body ratio,liver tissue morphology,serum liver transaminase or inflammatory factors between the hepatocyte NLRP3 knockout group and the control group in the same litter(P>0.05).Conclusion The Cre-LoxP gene knockout technology can be used to successfully construct a hepatocyte-specific NLRP3 gene knockout mouse model,providing an important technical support for the next step of studying the function of the NLRP3 gene in the liver at the animal level.

Porcine arthritis,one of the common chronic diseases in large-scale pig farms,can signifi-cantly reduce the production performance of meat pigs.In this study,a strain of Haemophilus pa-rasuis(HPS)was isolated from the joint fluid of a lame pig.The HPS was analyzed in terms of se-rotypes,virulence genes,and resistance genes.Additionally,it was treated with sensitive antibiotics to provide a theoretical basis for the comprehensive prevention and treatment of arthritis in meat pigs in future production settings.A strain of HPS type 14 was isolated from the joint fluid of dis-eased pigs.The HPS isolate demonstrated sensitivity to β-lactams and tetracyclines,while florfeni-col and polymyxin effectively inhibited its growth at low concentrations.However,the bacteria ex-hibited resistance to sulfonamides and ciprofloxacin.The treatment of affected pigs with clinical ar-thritis using doxycycline and enrofloxacin injections proved effective.Compared to the infected group,in which the sick pigs experienced difficulty flexing their carpal and tarsal joints and exhibi-ted significant lameness,the pigs in the treatment group showed marked improvement.Their joints were only slightly swollen,and the clinical symptoms of arthropathy were alleviated.

Body weight abnormalities, including overweight, obesity, and underweight, have become a dual public health challenge in Chinese adults: overweight and obesity lead to a variety of chronic complications, while underweight increases the risks of malnutrition, sarcopenia, and organ dysfunction. To systematically address these issues, multidisciplinary experts in endocrinology, sports science, nutrition, and psychiatry from various regions have held multiple weight management seminars. Based on the latest epidemiological data and clinical evidence, they expanded the guideline to include assessment and intervention strategies for underweight, in addition to the core content of obesity management. This guideline outlines the etiological mechanisms, evaluation methods, and multidimensional management strategies for overweight and obesity, covering key areas such as diagnosis and assessment, medical nutrition therapy, exercise prescription, pharmacological intervention, and psychological support. It is intended to provide a scientific and standardized approach to weight management across the adult population, aiming to curb the rising prevalence of obesity, mitigate complications associated with abnormal body weight, and improve nutritional status and overall quality of life.

Objective To propose an in vitro cytotoxicity evaluation method for novel iron-based biodegradable mateirals focusing on their degrading characteristics.Methods Half-finished scaffolds of nitrided iron tubes with a higher iron content of over 99％and a nitrogen content of 0.03％to 0.20％were selected as test samples,and based on the treatment mode were divided into an anaerobic treatment group,a non-anaerobic treatment group,a non-anaerobic treatment with removed iron particle group and a non-anaerobic treatment with plate-washing group.The anaerobic treatment group was processed in an anaerobic workstation;the conventional treatment group underwent standard handling in a biosafety cabinet;the conventional treatment with removed iron particle group was subjected to iron particle elimination using a Midimacs Starting Kit manual sorter after conventional treatment;and the conventional treatment with plate-washing group was rinsed with 0.9％sodium chloride injection before tetrazolium salt reagent treatment.Different extraction media(simulated body fluid,cell culture medium,phosphate buffer and 0.9％sodium chloride injection)were used for the immersion treatment of the test samples in each group to compare the effects of the degradation products on the survival rate of L929 cells.Results The anaerobic treatment group and the conventional treatment with removed iron particle group exhibited no detectable cytotoxicity.Trypan blue staining revealed significant cytotoxicity in the conventional treatment group,while false-negative results emerged due to interactions between the tetrazolium salt reagent and degradation products.In the non-anaerobic treatment with washing plate group,the false negative from iron particles was eliminated while potential cytotoxicity was showen,and the result accuracy was affected because some cells were washed out.Conclusion The proposed method can be used for the in vitro cytotoxicity evaluation,and facilitates the safety evaluation of the application of such materials.[Chinese Medical Equipment Journal,2025,46(3):35-41]