ObjectiveGastric hemorrhage is one of the most common and life-threatening emergencies of the upper digestive tract. Early identification and continuous monitoring are essential for reducing rebleeding rates and mortality, particularly within the critical early hours after onset. Although endoscopy and radiological imaging can accurately localize bleeding sites, these approaches are invasive, resource-intensive, and unsuitable for continuous bedside monitoring. Electrical impedance tomography (EIT), as a noninvasive and radiation-free functional imaging technique, offers real-time visualization of conductivity distribution and has the potential for detecting intragastric bleeding based on the electrical contrast between blood and surrounding gastric tissues. In this study, a three-dimensional gastric EIT (3D-gEIT) framework is proposed to achieve noninvasive, real-time, and dynamic monitoring of gastric hemorrhage, with emphasis on spatial localization and quantitative volume assessment. MethodsA three-dimensional upper-abdominal simulation model incorporating the stomach, gastric wall, gastric contents, and surrounding tissues was established. Three electrode configurations, namely the dual layer ring, the four layer staggered ring, and the opposed dual plane array, were designed and systematically compared to evaluate their influence on depth sensitivity and spatial resolution. Based on the Tikhonov-Noser hybrid regularization scheme, a region-clustering constraint was introduced to develop the TK-Noser-RCC algorithm. This approach aggregates spatially adjacent elements with similar conductivity variations, thereby enhancing structural continuity and suppressing isolated noise artifacts. To validate the proposed framework, an upper-abdominal physical phantom was constructed using agar to simulate background tissue conductivity. Hemispherical high-conductivity inclusions with volumes ranging from 10 ml to 50 ml were attached to the inner gastric wall to mimic localized bleeding under different gastric filling states. Boundary voltages were acquired under a 120 kHz excitation current and reconstructed using the TK-Noser-RCC algorithm. Furthermore, an in vivo animal experiment was performed using a porcine model with adult-scale abdominal dimensions. A total of 100 ml of autologous blood was injected incrementally into the stomach to simulate progressive gastric hemorrhage, and time-difference EIT reconstruction was conducted at each injection stage to assess the dynamic system response under physiological conditions. ResultsSimulation results demonstrated that the opposed dual-plane electrode array achieved superior depth sensitivity distribution and spatial resolution. For a 40 ml hemorrhage model, the average ICC and SSIM improved by 55.9% and 38.8% compared with the dual-layer ring configuration, and by 64.0% and 39.5% compared with the four-layer staggered configuration. The proposed region-clustering constraint significantly enhanced reconstruction stability. Under added Gaussian noise of 40 dB and 30 dB, ICC values remained approximately 0.85, indicating effective artifact suppression and preservation of boundary integrity. In physical phantom experiments, reconstructed hemorrhage volumes increased approximately linearly with the preset hemispherical volumes, and the reconstructed high-conductivity regions closely matched the actual bleeding locations. Both empty-stomach and full-stomach conditions were evaluated, demonstrating that the opposed dual-plane configuration maintained stable imaging performance across varying gastric contents. In the animal experiment, reconstructed low-impedance regions expanded progressively with increasing injected blood volume. The spatial localization of the hemorrhage remained stable throughout the procedure, and no significant artifacts were observed. Quantitative analysis showed that reconstructed volume and average conductivity variation exhibited an approximately linear growth trend with injected blood volume, confirming the sensitivity of the system to dynamic intragastric conductivity changes. ConclusionThe proposed 3D-gEIT framework enables quantitative reconstruction of gastric hemorrhage volume and spatial distribution with improved depth sensitivity, structural continuity, and noise robustness compared with conventional EIT approaches. By integrating optimized electrode configuration and a region-clustering-constrained reconstruction algorithm, the system provides stable dynamic monitoring under both controlled phantom conditions and in vivo physiological environments. This method offers a noninvasive, real-time, and low-cost imaging strategy for early diagnosis, postoperative monitoring, and bedside surveillance of gastric bleeding.

ObjectiveFat infiltration has been shown to be closely related to muscle mass loss and a variety of muscle diseases. This study proposes a method based on phase-angle electrical impedance tomography (ΦEIT) to visualize the electrical characteristic response caused by muscle fat infiltration, aiming to provide a new technical means for early non-invasive detection of muscle mass deterioration. MethodsThis study was divided into two parts. First, a laboratory pork model was constructed to simulate different degrees of fat infiltration by injecting1 ml or 2 ml of emulsified fat solution into different muscle compartments, and the phase angle images were reconstructed using ΦEIT. Second, a human experiment was conducted to recruit healthy subjects (n=8) from two age groups (20-25 years old and 26-30 years old). The fat content percentage η_fat of the left and right legs was measured by bioelectrical impedance analysis (BIA), and the phase angle images of the left and right calves were reconstructed using ΦEIT. The relationship between the global average phase angle Φ_M and the spatial average phase angle Φ_Mi of each muscle compartment and fat infiltration was further analyzed. ResultsIn the laboratory pork model, the grayscale value of the image increased with the increase of η_fat and Φ_M showed a downward trend. The results of human experiments showed that at the same fat content percentage, the Φ_M of the 26-30-year-old group was about 20%-35% lower than that of the 20-25-year-old group. The fat content percentage was significantly negatively correlated with Φ_M. In addition, the M₂ (soleus) compartment was most sensitive to fat infiltration, and the spatial average phase angles of the M₂ (soleus), M₃ (tibialis posterior and flexor digitorum longus), and M₄ (tibialis anterior, extensor digitorum longus, and peroneus longus) compartments all showed significant inter-group differences. ConclusionΦEIT imaging can effectively distinguish different degrees of fat infiltration, especially in deep, small or specially located muscles, showing high sensitivity, demonstrating the potential application of this method in local muscle mass monitoring and early non-invasive diagnosis.

Objective To explore the long-term efficacy of percutaneous pulmonary valve implantation(PPVI)and the durability of the domestic self-expanding Venus P valve.Methods A total of 8 patients with post-surgical right ventricular outflow tract(RVOT)dysfunction,who were admitted to hospital from October 2014 to July 2016 and deemed anatomically suitable for PPVI with self-expanding valve,were included prospectively.Clinical,imaging,procedural and follow-up data were analyzed.The survival rates,perioperative and long-term complication rates,long-term efficacy of PPVI,and long-term function of Venus P in 8 patients were evaluated.The immediate procedural results were evaluated by clinical implant success rate,which is defined as successful valve implantation with echocardiography-assessed pulmonary regurgitation＜moderate and peak trans-pulmonary pressure gradient＜40 mmHg.Results A total of 8 patients were included,with 7 females,aged 14 to 36 years.The initial diagnosis included post-surgical Tetralogy of Fallot(5 cases),post-surgical Trilogy of Fallot(1 case),post-surgical Quadricuspid pulmonary valve stenosis(1 case)and post-surgical Double-Outlet Right Ventricle(1 case).The indications of PPVI included RVOT-pulmonary obstruction and regurgitation(1 case)and isolated regurgitation(7 cases).Clinical implant success was achieved in all of the 8 patients with firmly fixed valve,and there were no such complications as valve detachment,displacement or stent fracture.All patients experienced significant symptom relief after the procedure.The right ventricular end-diastolic volume index(RVEDVi)measured by CMR 6 months after PPVI showed a significant decrease compared to preprocedural values[(89.99±13.85)ml/m2 vs.(144.93±11.28)ml/m2,P=0.001].Postoperative pulmonary regurgitation were significantly improved or disappeared in all patients,and there was no statistically significant difference in the average peak pressure gradient measured by echocardiogram between preoperative and the latest follow-up[(23.25±8.39)mmHg vs.(18.75±6.28)mmHg,P=0.210].Over an average follow-up period of(9.25±0.71)years,1 case of infective endocarditis occurred 5 years after PPVI.During the follow-up,no death,deterioration of heart failure,malignant arrhythmia or other serious complications were observed.All patients completed 8-year follow-up,and 3 completed 10-year follow-up.All patients were graded as NYHA functional class one at the latest follow-up.Conclusions PPVI using the domestically produced self-expanding Venus P is safe and feasible for the treatment of patients with post-surgical RVOT dysfunction and suitable anatomy.Our study confirms the long-term efficacy and durability of Venus P from multiple perspectives,and no severe stent fracture occurred without pre-stent implantation in the native RVOT.

Objective:To propose an alarm method for ventilator fault and abnormality of machine signs based on convolutional neural network(CNN)model,which aimed at the problem of low detection rate of ventilator faults and abnormalities of machine sign,and to analyze its application value in patients with chronic obstructive pulmonary disease(COPD)in using non-invasive ventilator.Methods:This study established a identification model(CNN-SG)for ventilator fault based on stochastic gradient descent by mini-batch method that was introduced by CNN network,and a multi-task CNN identification model for abnormalities of machine signs of ventilator was established on the basis of CNN model.The respiratory waveform data of 60 patients with chronic obstructive pulmonary disease(COPD)who admitted to Wusong Hospital,Zhongshan Hospital Affiliated to Fudan University from January 2019 to January 2024 were collected.These data were divided into train set(42 cases)and validation set(18 cases)as ratio of 7 to 3.The training set was used in the learning process of model,while the validation set was used to assess the model's performance for unknown data.One-hot encoding was used to represent fault states,and to predict whether occurred abnormal data failures within specific time intervals.Two independent convolutional networks were employed respectively to detect and identify invalid inspiratory effort and double-triggering abnormalities in abnormal machine signs.Model performance was assessed by using accuracy,precision,recall rate,negative predictive value(NPV),and specificity.Chi-square test was used to compare the differences of various assessment indicators between different models.The F1-score was calculated to comprehensively assess the performance of model.Results:In the validation set,the accuracy(99.98%),precision(99.90%),recall rate(99.97%),NPV(98.68%),and specificity(98.24%)of CNN-SG model were higher than those of CNN model in identify the fault of ventilator.In detecting invalid inspiratory effort,the accuracy,sensitivity,specificity and F1-scores of CNN-MTL model were respectively 98.83%,98.81%,97.68%and 98.85.The accuracy,sensitivity,specificity and F1-scores of CNN-MTL model were respectively 98.70%,98.83%,97.62%,and 98.75 in identifying double-triggering positive features,as well as 98.80%,98.81%,98.88%and 98.99 for double-triggering negative features.All of the above indicators of CNN-SG were significantly better than those of the conventional CNN model.Conclusion:The established deep learning algorithm model based on CNN can effectively identify faults and abnormalities of machine signs of non-invasive ventilator.

Objective:To explore the efficacy and safety of sivelestat sodium in patients with acute respiratory distress syndrome (ARDS) in the intensive care unit (ICU).Methods:Sixty patients with ARDS admitted to the ICU of the Fuyang Hospital Affiliated to Anhui Medical University from August 1, 2023 to November 1, 2024 were selected and divided into the control group (conventional treatment, 30 cases) and the sivelestat sodium group (treated with sivelestat sodium in addition to conventional treatment, 30 cases) by the random number table method. The clinical data such as inflammatory factors, blood gas analysis indicators, Acute Physiology and Chronic Health Evaluation (APACHE) Ⅱ score and Sequential Organ Failure Assessment (SOFA) score of the two groups of patients before treatment and 3 days after treatment were compared. The prognostic indicators such as mechanical ventilation time, ICU stay time, total hospital stay time, 28-day mortality rate and clinical efficacy of the two groups of patients were compared.Results:Before treatment, there were no statistically significant differences in inflammatory factors, blood gas analysis indicators, APACHE Ⅱ score and SOFA score between the two groups of patients (all P>0.05). After 3 days of treatment, the improvement degrees of APACHE Ⅱ score, SOFA score, arterial partial pressure of oxygen (PaO 2), oxygenation index (PaO 2/FiO 2), procalcitonin (PCT), interleukin-6 (IL-6), and C-reactive protein (CRP) in the sivelestat sodium group were all greater than those in the control group. The differences were all statistically significant (all P<0.05); The mechanical ventilation time [(5.31±4.12) d vs (7.17±2.32)d] and ICU stay [(6.31±3.42)d vs (8.93±5.26)d] of patients in the sivelestat sodium group were significantly shorter than those in the control group, and the differences were statistically significant (all P<0.05). There was no statistically significant difference in the 28-day mortality rate between the sivelestat sodium group [20.00%(6/30)] and the control group [43.33%(13/30)] ( P>0.05). The total effective rate of treatment in the sivelestat sodium group was significantly higher than that in the control group [80.00%(24/30) vs 56.67%(17/30)], and the difference was statistically significant (χ 2=4.167, P=0.041). Conclusions:Sivelestat sodium is helpful in improving the physiological parameters of patients with ARDS, effectively reducing the levels of inflammatory factors in the body, shortening the duration of mechanical ventilation and ICU stay, but has no significant effect on the 28-day mortality rate.

This study was aimed at preliminarily investigating the molecular biological functions of the PPE65 protein from Myco-bacterium tuberculosis,and providing foundational data for tuberculosis prevention and control.The basic biological properties of the PPE65 gene-encoded protein were predicted with bioinformatics tools.Sequence information for the Mycobacterium tuberculosis Rv3621c gene and PPE65 protein was retrieved from the NCBI database.The Rv3621c gene was amplified through PCR with the H37Rv genome as a template,then cloned into the pET22b(+)expression vector.The recombinant pET22b(+)-PPE65 plasmid was transformed into Escherichia coli BL21(DE3)competent cells for IPTG-induced expression.Solubility analysis,purification,and identification of the recombinant PPE65 protein were performed.BEAS-2B cells were treated with various concentrations of PPE65 protein for 24 h,and cell proliferation was assessed with CCK-8 assays.PPE65 was found to be composed of 413 amino acids and to have a molecular formula of C????H????N???O???S??,a relative molecular mass of 40 679.88,a theoretical isoelectric point of 4.60,an ali-phatic index of 81.94,and an average hydrophilicity value of 0.319,thus indicating a stable hydrophobic protein lacking signal pep-tides or transmembrane domains.Secondary structure analysis revealed 53.03%α-helix(Hh),2.66%β-sheet(Ee),and 44.31%ran-dom coil(Cc).Bioinformatics predictions identified 38 B-cell epitopes and 22 CTL/Th-cell epitopes.The full-length PPE65 gene(1 308 bp)was confirmed through double restriction enzyme digestion and sequencing,thereby validating the correct construction of the pET22b(+)-PPE65 recombinant plasmid.SDS-PAGE analysis demonstrated that the recombinant protein was found in inclusion bodies,and a single band at 43.7 kDa was observed after purification.Western blotting revealed specific binding to mouse-derived His monoclonal antibodies,thereby confirming successful expression of the PPE65 protein.BEAS-2B cells treated with a PPE65 protein concentration gradient(2.5-20 μg/mL)exhibited a dose-dependent increase in cell number.Compared with those in the PBS control group,TGF-β relative expression levels were significantly higher in all treatment groups(t2.5=4.893,P<0.001,t5.0=4.640,P<0.05,t10=7.535,P<0.05,t20=16.44,P<0.000 1).This study elucidated the structural characteristics of the PPE65 protein,successfully obtained the recombinant protein through prokaryotic expression and purification,and demonstrated its ability to promote BEAS-2B cell proliferation.The underlying mechanism might involve suppression of TGF-β/S mad signaling pathway activation.These findings provide a theoretical basis for understanding the role and regulatory mechanisms of PPE65 during M.tuberculosis infection.

Objective:To investigate the differences in respiratory work load and oxygenation index improvement between intermittent sighing and progressive lung retraction strategies in patients with acute respiratory distress syndrome(ARDS)related to lung collapse.Methods:Sixty patients with ARDS related to lung collapse admitted from January 2020 to January 2024 were selected and divided into intermittent sighing group(IS group,n=30)and progressive lung re-expansion group(PLR group,n=30)according to different treatment methods.The IS group used an intermittent sighing ventilation mode,while the PLR group adopted a progressive lung re-expansion strategy.The changes in respiratory work load indicators[including work of breathing(WOB),maximum inspiratory pressure(Pmax),transcutaneous oxygen saturation(SpO2)],oxygenation index(PaO2/FiO2),lung compliance(Cst),and mechanical ventilation-related parameters were compared before and after treatment in both groups.Results:After treatment,the respiratory work load was significantly reduced in both groups,with a more pronounced decrease in WOB in the PLR group(P＜0.05);both groups showed significant improvements in oxygenation index,but the degree of improvement was more marked in the PLR group(P＜0.01);lung compliance improved more markedly in the PLR group(P＜0.05);the PLR group had significantly shorter mechanical ventilation time and ICU stay compared to the IS group(P＜0.05).Conclusions:The progressive lung recruitment strategy is better than the intermittent sighing ventilation in improving the respiratory work load,oxygenation index and lung compliance of patients with ARDS related to lung collapse.It can shorten the mechanical ventilation time and ICU hospital stay more effectively,which is worth clinical promotion and application.

This study explored whether Astragalus polysaccharide(APS)can regulate the VEGF/VEGFR signaling pathway to affect the proliferative activity of rat intestinal mucosal microvascu-lar endothelial cells(RIMMVECs).RIMMVECs were isolated from newborn rats,then purified and treated with APS at concentrations of 0.1,1.0,10.0,100.0,1 000.0,and 10 000.0 mg/L.MTT was used to determine the effect of APS on RIMMVECs proliferation and screen for the optimal concentration of APS.Subsequently,flow cytometry was used to detect the changes in cell cycle to evaluate the stage of action of APS on the cell cycle in RIMMVECs.Then,the ELISA was used to detect the changes of VEGFA in cell supernatant to evaluate the potential of cell proliferation and angiogenesis.The changes in fluorescence intensity of Fluo-8AM was observed using fluorescence microscopy to evaluate intracellular Ca2+levels.Finally,Western blot was used to detect the ex-pression of PERK in RIMMVECs to analyze the possible mechanism of APS.The results showed that 100 mg/L APS significantly enhanced the proliferative activity of RIMMVECs,increased the content of VEGFA in the cell supernatant,the intracellular Ca2+levels,and the expression of PERK protein,indicating that APS promotes the proliferation of RIMMVECs,which may be a-chieved by promoting the expression of VEGFA and activating the ERK pathway.

Objective:To investigate the differences in respiratory work load and oxygenation index improvement between intermittent sighing and progressive lung retraction strategies in patients with acute respiratory distress syndrome(ARDS)related to lung collapse.Methods:Sixty patients with ARDS related to lung collapse admitted from January 2020 to January 2024 were selected and divided into intermittent sighing group(IS group,n=30)and progressive lung re-expansion group(PLR group,n=30)according to different treatment methods.The IS group used an intermittent sighing ventilation mode,while the PLR group adopted a progressive lung re-expansion strategy.The changes in respiratory work load indicators[including work of breathing(WOB),maximum inspiratory pressure(Pmax),transcutaneous oxygen saturation(SpO2)],oxygenation index(PaO2/FiO2),lung compliance(Cst),and mechanical ventilation-related parameters were compared before and after treatment in both groups.Results:After treatment,the respiratory work load was significantly reduced in both groups,with a more pronounced decrease in WOB in the PLR group(P＜0.05);both groups showed significant improvements in oxygenation index,but the degree of improvement was more marked in the PLR group(P＜0.01);lung compliance improved more markedly in the PLR group(P＜0.05);the PLR group had significantly shorter mechanical ventilation time and ICU stay compared to the IS group(P＜0.05).Conclusions:The progressive lung recruitment strategy is better than the intermittent sighing ventilation in improving the respiratory work load,oxygenation index and lung compliance of patients with ARDS related to lung collapse.It can shorten the mechanical ventilation time and ICU hospital stay more effectively,which is worth clinical promotion and application.

This study was aimed at preliminarily investigating the molecular biological functions of the PPE65 protein from Myco-bacterium tuberculosis,and providing foundational data for tuberculosis prevention and control.The basic biological properties of the PPE65 gene-encoded protein were predicted with bioinformatics tools.Sequence information for the Mycobacterium tuberculosis Rv3621c gene and PPE65 protein was retrieved from the NCBI database.The Rv3621c gene was amplified through PCR with the H37Rv genome as a template,then cloned into the pET22b(+)expression vector.The recombinant pET22b(+)-PPE65 plasmid was transformed into Escherichia coli BL21(DE3)competent cells for IPTG-induced expression.Solubility analysis,purification,and identification of the recombinant PPE65 protein were performed.BEAS-2B cells were treated with various concentrations of PPE65 protein for 24 h,and cell proliferation was assessed with CCK-8 assays.PPE65 was found to be composed of 413 amino acids and to have a molecular formula of C????H????N???O???S??,a relative molecular mass of 40 679.88,a theoretical isoelectric point of 4.60,an ali-phatic index of 81.94,and an average hydrophilicity value of 0.319,thus indicating a stable hydrophobic protein lacking signal pep-tides or transmembrane domains.Secondary structure analysis revealed 53.03%α-helix(Hh),2.66%β-sheet(Ee),and 44.31%ran-dom coil(Cc).Bioinformatics predictions identified 38 B-cell epitopes and 22 CTL/Th-cell epitopes.The full-length PPE65 gene(1 308 bp)was confirmed through double restriction enzyme digestion and sequencing,thereby validating the correct construction of the pET22b(+)-PPE65 recombinant plasmid.SDS-PAGE analysis demonstrated that the recombinant protein was found in inclusion bodies,and a single band at 43.7 kDa was observed after purification.Western blotting revealed specific binding to mouse-derived His monoclonal antibodies,thereby confirming successful expression of the PPE65 protein.BEAS-2B cells treated with a PPE65 protein concentration gradient(2.5-20 μg/mL)exhibited a dose-dependent increase in cell number.Compared with those in the PBS control group,TGF-β relative expression levels were significantly higher in all treatment groups(t2.5=4.893,P<0.001,t5.0=4.640,P<0.05,t10=7.535,P<0.05,t20=16.44,P<0.000 1).This study elucidated the structural characteristics of the PPE65 protein,successfully obtained the recombinant protein through prokaryotic expression and purification,and demonstrated its ability to promote BEAS-2B cell proliferation.The underlying mechanism might involve suppression of TGF-β/S mad signaling pathway activation.These findings provide a theoretical basis for understanding the role and regulatory mechanisms of PPE65 during M.tuberculosis infection.