Nine compounds were isolated and purified from 90% ethanol extract of Alstonia mairei Lévl by using various chromatographic methods, including silica gel, SephadexLH-20, MCI Gel and ODS column chromatography, combined with semi-preparative liquid phase separation methods. Modern spectroscopic methods (1D and 2D NMR, UV, IR, MS, etc.) were used to identify the structures of the isolated compounds. They were identified as mairoside A (1), 3′,6-di-O-sinaloylsucrose (2), myristic acid (3), methyl myristate (4), ethyl myristate (5), 3,4,5-trimethoxycinnamic acid (6), 3,4,5-trimethoxybenzoic acid (7), vinoline (8), kaempferol-3-O-rutinoside (9), among which compound 1 is a new glycoside, compounds 4 and 5 are new natural products, and the nuclear magnetic data of compound 4 were reported for the first time.

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.

Objective To analyze the characteristics of adult anomalous aortic origin of coronary artery(AAOCA)and the causes of missed diagnosis by transthoracic echocardiography(TTE)so as to facilitate TTE in diagnosing adult AAOCA.Methods A total of 37 adult patients with AAOCA diagnosed by non-invasive coronary CT angiography(CCTA)and/or invasive coronary angiography(ICA)were selected as research samples at some hospital from January 2019 to December 2022,and their clinical symptoms and the findings of 12-lead electrocardiogram,cardiac enzymes and TTE were summarized;the patients were typed according to the site of origin of coronary artery anomalies,and the causes for the missed diagnosis of TTE were eplored.Chi-square test was used to compare the differences in TTE missed diagnoses.Results Of the 37 patients,31 ones had no or only mild symptoms;most ones had negative results in terms of 12-lead electrocardiography,cardiac enzymes,changes in the size of the cardiac chambers,segmental ventricular wall motion abnormalities and left ventricular systolic function.The patients with anomalous origin of the right coronary artery from left sinus(ARCA-L)gained the largest proportion of 59.45％(22/37);21 patients were diagnosed with anomalous origin of coronary artery arising from the opposite sinus(ACAOS)in the two examinations of TTE,of whom there were 19 cases of ARCA-L,and the detection rate of ACAOS by TTE was 87.5％;all the 13 patients origins in branches and high-grade openings were missed by TTE.The detection rate of ACAOS by TTE was significantly higher than that of coronary artery anomalies originating in branches and in high openings,and the difference was statistically significant(21/24 vs 0/13,P＜0.001).Conclusion Most adult AAOCA patients lack specificity in symptoms and related examination results.TTE has a high detection rate of ACAOS,while it is easy to miss the diagnosis of coronary artery anomalies originating from branches and high openings.Ultrasonographers have to identify false negative AAOCA by multi-section and multi-angle scanning and color Doppler flow imaging in order to reduce the rate of missed diagnosis.[Chinese Medical Equipment Journal,2024,45(1):71-75]

The growth of three plague phages from Qinghai Plateau in two Yersinia pestis strains(plague vaccine strains EV76 and 614F)and four non-Yersinia pestis strains(Yersinia pseudotuberculosis PTB3,PTB5,Escherichia coli V517,and Yersinia enterocolitica 52302-2)were detected through a micromethod based on the OmniLogTM microbial identification system and by the drop method,to provide a scientific basis for future ecological studies and classification based on the host range.For plague vaccine strains EV76 and 614F,successful phage infection and subsequent phage growth were observed in the host bacte-rium.Diminished bacterial growth and respiration and a concomitant decrease in color were observed with the OmniLogTM mi-crobial identification system at 33 ℃ for 48 h.Yersinia pseudotuberculosis PTB5 was sensitive to Yersinia pestis phage 476,but Yersinia pseudotuberculosis PST5 was insensitive to phage 087 and 072204.Three strains of non-Yersinia pestis(Yersinia pseudotuberculosis PTB3,Escherichia coli V517,and Yersinia enterocolitica 52302-2)were insensitive to Yersinia pestis pha-ges 087,072204,and 476 showed similar growth curves.The growth of phages 476 and 087,as determined with the drop method,in two Yersinia pestis strains(plague vaccine strains EV76 and 614F)and four non-Yersinia pestis strains(Yersinia pseudotuberculosis PTB3,Escherichia coli V517,and Yersin-ia enterocolitica 52302-2)showed the same results at 37 ℃,on the basis of comparisons with the OmniLogTM microbial i-dentification system;in contrast,phages 072204 did not show plaques on solid medium at 37 ℃ with plague vaccine strains EV76 and 614F.Determination based on the OmniLogTM detection system can be used as an alternative to the traditional determination of the host range,thus providing favorable application val-ue for determining the interaction between the phage and host bacteria.

Objective:The purpose of this study was to examine the clinical features and initial treatment outcomes of elderly individuals with idiopathic membranous nephropathy.Methods:This study retrospectively analyzed the clinical characteristics and therapeutic effect of hospitalized patients aged 60 years or older with renal-biopsy-proven idiopathic membranous nephropathy for at least one year.Results:This study enrolled a total of 91 elderly patients with IMN, consisting of 51 males(56.0%)and 40 females(44.0%). The median age of the patients was 67 years.The urinary protein creatinine ratio(uPCR)and urinary albumin creatinine ratio(uACR)of the patients were 4 454.3 mg/g and 2 258.5 mg/g, respectively.The median 24-hour urinary protein and urinary albumin levels were 5 098.2 mg/24 h and 2 800.6 mg/24 h, respectively.The average estimated glomerular filtration rate(eGFR)was(60.5±20.4)ml·min -1·1.73 m -2.Out of the total of 61 patients, 67.0% achieved remission, including complete and partial remission, within a year of renal biopsy.The levels of uPCR and uACR were significantly higher in the non-remission group compared to the remission group(5 462.5 vs.2 271.1 mg/g, P<0.001; 2 774.4 vs.1 320.0 mg/g, P=0.001). Additionally, the levels of 24h urinary protein and urinary albumin were significantly higher in the non-remission group compared to the remission group(6 526.4 vs.3 210.4 mg/g, P=0.002; 3 067.7 vs.2 102.4 mg/g, P=0.007). The remission group had a higher proportion of patients receiving immunosuppressive therapy(85.2% vs.33.3%, P<0.001). The remission rates were higher in patients treated with glucocorticoid combined with cyclophosphamide, glucocorticoid combined with calcineurin inhibitors, or glucocorticoid combined with mycophenolate mofetil compared to those receiving conservative treatment(88.2% vs.31.0%, P=0.001; 80.0% vs.31.0%, P<0.001; 100.0% vs.31.0%, P=0.007). There was no significant difference in remission rate between the three immunosuppressive therapy groups( P>0.05). However, upon further analysis, it was found that the levels of uPCR, uACR, and serum cystatin C(CysC)were higher in the immunosuppressive therapy groups compared to conservative treatment.Additionally, serum total protein and albumin were lower in the immunosuppressive therapy groups, and these differences were statistically significant( P<0.05). Conclusions:The majority of elderly patients diagnosed with IMN have multiple comorbidities.For those at high risk with elevated urinary protein levels, early initiation of immunosuppressive therapy may lead to a higher initial urinary protein remission rate.Therefore, it is advisable to develop individualized treatment plans for elderly patients with IMN based on their clinical characteristics, as well as the risks and benefits associated with immunosuppressive therapy.

Objective China is among the 30 countries with a high burden of tuberculosis(TB)worldwide,and TB remains a public health concern.Kashgar Prefecture in the southern Xinjiang Autonomous Region is considered as one of the highest TB burden regions in China.However,molecular epidemiological studies of Kashgar are lacking. Methods A population-based retrospective study was conducted using whole-genome sequencing(WGS)to determine the characteristics of drug resistance and the transmission patterns. Results A total of 1,668 isolates collected in 2020 were classified into lineages 2(46.0%),3(27.5%),and 4(26.5%).The drug resistance rates revealed by WGS showed that the top three drugs in terms of the resistance rate were isoniazid(7.4%,124/1,668),streptomycin(6.0%,100/1,668),and rifampicin(3.3%,55/1,668).The rate of rifampicin resistance was 1.8%(23/1,290)in the new cases and 9.4%(32/340)in the previously treated cases.Known resistance mutations were detected more frequently in lineage 2 strains than in lineage 3 or 4 strains,respectively:18.6%vs.8.7 or 9%,P<0.001.The estimated proportion of recent transmissions was 25.9%(432/1,668).Multivariate logistic analyses indicated that sex,age,occupation,lineage,and drug resistance were the risk factors for recent transmission.Despite the low rate of drug resistance,drug-resistant strains had a higher risk of recent transmission than the susceptible strains(adjusted odds ratio,1.414;95%CI,1.023-1.954;P = 0.036).Among all patients with drug-resistant tuberculosis(DR-TB),78.4%(171/218)were attributed to the transmission of DR-TB strains. Conclusion Our results suggest that drug-resistant strains are more transmissible than susceptible strains and that transmission is the major driving force of the current DR-TB epidemic in Kashgar.

Objective Recombinase-aided polymerase chain reaction(RAP)is a sensitive,single-tube,two-stage nucleic acid amplification method.This study aimed to develop an assay that can be used for the early diagnosis of three types of bacteremia caused by Staphylococcus aureus(SA),Pseudomonas aeruginosa(PA),and Acinetobacter baumannii(AB)in the bloodstream based on recombinant human mannan-binding lectin protein(M1 protein)-conjugated magnetic bead(M1 bead)enrichment of pathogens combined with RAP. Methods Recombinant plasmids were used to evaluate the assay sensitivity.Common blood influenza bacteria were used for the specific detection.Simulated and clinical plasma samples were enriched with M1 beads and then subjected to multiple recombinase-aided PCR(M-RAP)and quantitative PCR(qPCR)assays.Kappa analysis was used to evaluate the consistency between the two assays. Results The M-RAP method had sensitivity rates of 1,10,and 1 copies/μL for the detection of SA,PA,and AB plasmids,respectively,without cross-reaction to other bacterial species.The M-RAP assay obtained results for<10 CFU/mL pathogens in the blood within 4 h,with higher sensitivity than qPCR.M-RAP and qPCR for SA,PA,and AB yielded Kappa values of 0.839,0.815,and 0.856,respectively(P<0.05). Conclusion An M-RAP assay for SA,PA,and AB in blood samples utilizing M1 bead enrichment has been developed and can be potentially used for the early detection of bacteremia.

Objective To compare the effectiveness of TiRobot assisted F screw technique and inverted triangle parallel nail internal fixation in the treatment of unstable femoral neck fractures.Methods A retrospective analysis was conducted on 72 patients with unstable femoral neck fractures who were treated with percutaneous cannulated screw fixation assisted with TiRobot Orthopaedic robot from December 2019 to April 2021.Among them,37 patients were treated with F screw internal fixa-tion,including 16 males and 21 females,aged47 to 64years old with an average of(53.87±5.28)years old;According to Pauwels classification,there were 1 case of type Ⅰ,19 cases of type Ⅱ,17 cases of type Ⅲ;8 cases of combined medical diseases;17 cases of falling,8 cases of traffic accident and 12 cases of falling from height;The time from injury to operation was 29 to 49 hours with average of(35.00±7.34)hours.Another 35 cases used internal fixation with an inverted triangle parallel nail,including 13 males and 22 females with an average age of 46 to 63 years old(52.36±5.05)years old;According to the Pauwels injury classifi-cation:there were 2 cases of type Ⅰ,21 cases of type Ⅱ,12 cases of type Ⅲ;6 cases of medical diseases,15 cases of falling in-jury,9 cases of traffic accident,11 cases of falling injury;The time from injury to operation was 30 to 45 hours with an average of(33.00±6.83)h.The intraoperative blood loss,operation time,intraoperative fluoroscopy times,follow-up time,fracture healing time,postoperative complications were observed and compared between the two groups.The hip joint function was e-valuated by Harris score at 6 months and 12 months after operation.Results There was no significant difference in operation time,intraoperative blood loss,intraoperative fluoroscopy times and other intraoperative data between two groups(P＞0.05).Both groups were followed up regularly,and the follow-up time was 12 to 16 months.The fracture healing time and Harris score of the F screw internal fixation group were better than those of the inverted triangle parallel nail internal fixation group(P＜0.05).There was 1 case of femoral neck shortening in the F screw internal fixation group,1 case of nonunion,1 case of nail withdrawal,and 1 case of lower extremity deep vein thrombosis in the inverted triangle internal fixation group.The incidence of complications in the F screw internal fixation group was lower than that in the inverted triangle parallel nail internal fixation group(P＜0.05).Conclusion Percutaneous cannulated F screw technique using Tirobot navigation positioning system is a safe and effective treatment for patients with unstable femoral neck fractures.It can significantly shorten the fracture healing time,reduce the incidence of postoperative complications,significantly improve hip joint function,and improve the quality of life.

Background and aim:Hepatic ischemia-reperfusion injury(IRI)is a significant challenge in liver trans-plantation,trauma,hypovolemic shock,and hepatectomy,with limited effective interventions available.This study aimed to investigate the role of leukocyte cell-derived chemotaxin 2(LECT2)in hepatic IRI and assess the therapeutic potential of Lect2-short hairpin RNA(shRNA)delivered through adeno-associated virus(AAV)vectors. Materials and methods:This study analyzed human liver and serum samples from five patients under-going the Pringle maneuver.Lect2-knockout and C57BL/6J mice were used.Hepatic IRI was induced by clamping the hepatic pedicle.Treatments included recombinant human LECT2(rLECT2)and AAV-Lect2-shRNA.LECT2 expression levels and serum biomarkers including alanine aminotransferase(ALT),aspartate aminotransferase(AST),creatinine,and blood urea nitrogen(BUN)were measured.Histological analysis of liver necrosis and quantitative reverse-transcription polymerase chain reaction were performed. Results:Serum and liver LECT2 levels were elevated during hepatic IRI.Serum LECT2 protein and mRNA levels increased post reperfusion.Lect2-knockout mice had reduced weight loss;hepatic necrosis;and serum ALT,AST,creatinine,and BUN levels.rLECT2 treatment exacerbated weight loss,hepatic necrosis,and serum biomarkers(ALT,AST,creatinine,and BUN).AAV-Lect2-shRNA treatment significantly reduced weight loss,hepatic necrosis,and serum biomarkers(ALT,AST,creatinine,and BUN),indicating thera-peutic potential. Conclusions:Elevated LECT2 levels during hepatic IRI increased liver damage.Genetic knockout or shRNA-mediated knockdown of Lect2 reduced liver damage,indicating its therapeutic potential.AAV-mediated Lect2-shRNA delivery mitigated hepatic IRI,offering a potential new treatment strategy to enhance clinical outcomes for patients undergoing liver-related surgeries or trauma.

Objective:To explore the value of the imaging nomogram model based on preoperative CT features of patients with small intestinal stromal tumor (SIST) in predicting pathological risk classification.Methods:This was a cohort study. The patients who were diagnosed as primary SIST by postoperative pathology in Cancer Hospital, Chinese Academy of Medical Sciences from January 2014 to October 2023 were retrospectively included. According to the modified 2008 National Institutes of Health classification criteria, the patients were divided into a pathological intermediate/high-risk group (86 cases) and a very low/low-risk group (56 cases). The features of preoperative enhanced CT images of SIST were analyzed, including tumor boundary, necrosis, intra-tumoral hemorrhage, intra-tumoral calcification, growth pattern, enhancement pattern, enhancement degree, enlarged vessels feeding or draining the mass (EVFDM), and tumor location. Patients were followed up to determine the recurrence-free survival (RFS). Univariate and multivariate logistic regression were used to screen the independent predictors of SIST with pathological medium/high-risk group. The independent predictors were combined to construct an imaging prediction model, and a nomogram was drawn. The receiver operating characteristic curve was used to evaluate the predictive efficacy of the model. The Kaplan-Meier method was used to draw the survival curve, and the log-rank test was used to compare the differences in RFS.Results:Univariate logistic regression results showed that tumor shape, necrosis, intra-tumoral hemorrhage, EVFDM, and tumor location were potentially related to medium/high-risk SIST. Multivariate logistic regression results showed that tumor shape ( OR=3.92, 95% CI 1.58-9.71, P=0.003), necrosis ( OR=4.60, 95% CI 1.91-11.09, P<0.001), and EVFDM ( OR=6.25,95% CI 1.74-22.47, P=0.005) were independent predictors of pathological intermediate/high-risk SIST. The area under the curve of the imaging predictive model combining the three predictors to predict the intermediate/high-risk SIST was 0.835 (95% CI 0.769-0.901), the sensitivity was 0.810, the specificity was 0.839, and the accuracy was 0.789. Taking the cut-off value (0.810) as the boundary value, the patients were divided into the high-risk group (74 cases) and the low-risk group (68 cases) according to the prediction results. The median RFS of the predicted high-risk group was poorer than that of the predicted low-risk group, and the difference was statistically significant ( χ2=5.20, P=0.023). Conclusions:The imaging nomogram model based on preoperative CT image features shape, necrosis, and EVFDM can effectively predict the pathological intermediate/high-risk SIST before surgery and has important predictive value for postoperative recurrence.