Investigating the structural characteristics of proton tautomers is of great significance for understanding organic reactions and biochemical processes.In this study,a method based on ion mobility mass spectrometry combined with ab initio molecular dynamics calculations was proposed.The structures of proton tautomers were determined by comparing the experimental and theoretical collision-induced dissociation(CID)mass spectrograms of different proton tautomers.Ion mobility mass spectrometry was used to separate proton tautomerism produced during ionization.The CID mass spectra of each isomer could be obtained after mobility separation.The quantum chemical mass spectrometry(QCXMS)program based on ab initio molecular dynamics calculations was used to calculate the fragmentation process and obtain the theoretical CID mass spectra.The results of experiment and calculation showed that this method effectively solved the issue of difficult identification of proton tautomers.This method was also of great significance for the study of ionization mechanism and organic reaction process using mass spectrometry.

Tranexamic acid is widely used in joint orthopedic surgery.At the same time,it has high safety and few adverse drug reactions.It can effectively improve intraoperative bleeding and promote early functional recovery of patients.This article reviews the mode of administration,safe dose,administration time and adverse drug reactions of tranexamic acid in the perioperative period of joint replacement and arthroscopic surgery,in order to provide reference for the clinical application of tranexamic acid.

Objectives:To investigate the effect of the expression of low-density lipoprotein receptor associated protein (LDLR) on the vascular abnormalities in hepatocellular carcinoma (HCC) and its mechanisms.Methods:Based on the information of Oncomine Cancer GeneChip database, we analyzed the correlation between the expression level of LDLR and the expression level of carcinoembryonic antigen (CEA) and CD31 in hepatocellular carcinoma tissues. Lentiviral transfection of short hairpin RNA target genes was used to construct LDLR-knockdown MHCC-97H and HLE hepatocellular carcinoma cells. The differential genes and their expression level changes in LDLR-knockdown hepatocellular carcinoma cells were detected by transcriptome sequencing, real-time fluorescence quantitative polymerase chain reaction, and protein immunoblotting. The gene-related signaling pathways that involve LDLR were clarified by enrichment analysis. The effect of LDLR on CEA was assessed by the detection of CEA content in conditioned medium of hepatocellular carcinoma cells. Angiogenesis assay was used to detect the effect of LDLR on the angiogenic capacity of human umbilical vein endothelial cells, as well as the role of CEA in the regulation of angiogenesis by LDLR. Immunohistochemical staining was used to detect the expression levels of LDLR in 176 hepatocellular carcinoma tissues, and CEA and CD31 in 146 hepatocellular carcinoma tissues, and analyze the correlations between the expression levels of LDLR, CEA, and CD31 in the tissues, serum CEA, and alanine transaminase (ALT).Results:Oncomine database analysis showed that the expressions of LDLR and CEA in the tissues of hepatocellular carcinoma patients with portal vein metastasis were negatively correlated ( r=-0.64, P=0.001), whereas the expressions of CEA and CD31 in these tissues were positively correlated ( r=0.46, P=0.010). The transcriptome sequencing results showed that there were a total of 1 032 differentially expressed genes in the LDLR-knockdown group and the control group of MHCC-97H cells, of which 517 genes were up-regulated and 515 genes were down-regulated. The transcript expression level of CEACAM5 was significantly up-regulated in the cells of the LDLR-knockdown group. The Gene Ontology (GO) function enrichment analysis showed that the differential genes were most obviously enriched in the angiogenesis function. The Kyoto Encyclopedia of Genes and Genomes (KEGG) signaling pathway enrichment analysis showed that the relevant pathways involved mainly included the cellular adhesion patch, the extracellular matrix receptor interactions, and the interactions with the extracellular matrix receptors. The CEA content in the conditioned medium of the LDLR-knockdown group was 43.75±8.43, which was higher than that of the control group (1.15±0.14, P＜0.001). The results of angiogenesis experiments showed that at 5 h, the number of main junctions, the number of main segments, and the total area of the lattice formed by HUVEC cells cultured with the conditioned medium of MHCC-97H cells in the LDLR-knockdown group were 295.3±26.4, 552.5±63.8, and 2 239 781.0±13 8211.9 square pixels, which were higher than those of the control group (113.3±23.5, 194.8±36.5, and 660 621.0±280 328.3 square pixels, respectively, all P＜0.01).The number of vascular major junctions, the number of major segments, and the total area of the lattice formed by HUVEC cells cultured in conditioned medium with HLE cells in the LDLR-knockdown group were 245.3±42.4, 257.5±20.4, and 2 535 754.5±249 094.2 square pixels, respectively, which were all higher than those of the control group (113.3±23.5, 114.3±12.2, and 1 565 456.5±219 259.7 square pixels, respectively, all P＜0.01). In the conditioned medium for the control group of MHCC-97H cells,the number of main junctions, the number of main segments, and the total area of the lattice formed by the addition of CEA to cultured HUVEC cells were 178.9±12.0, 286.9±12.3, and 1 966 990.0±126 249.5 spixels, which were higher than those in the control group (119.7±22.1, 202.7±33.7, and 1 421 191.0±189 837.8 square pixels, respectively). The expression of LDLR in hepatocellular carcinoma tissues was not correlated with the expression of CEA, but was negatively correlated with the expression of CD31 ( r=-0.167, P=0.044), the level of serum CEA ( r=-0.061, P=0.032), and the level of serum ALT (r=-0.147, P=0.05). The expression of CEA in hepatocellular carcinoma tissues was positively correlated with the expression of CD31 ( r=0.192, P=0.020). The level of serum CEA was positively correlated with the level of serum ALT ( r=0.164, P=0.029). Conclusion:Knocking down LDLR can promote vascular abnormalities in HCC by releasing CEA.

This study aimed to investigate the therapeutic effects of Morinda officinalis iridoid glycosides (MOIG) on bone loss of rheumatoid arthritis (RA) rats, and the mechanism of osteoclast function and activity induced by lipopolysaccharide (LPS). RA rats were established by injecting bovin type II collagen. The Bio-ethic Committee of Zhejiang Chinese Medical University approved all experimental protocols associated with this study (IACUC-20180410-03). The collagen-induced arthritis (CIA) rats were administered drug by gavage for 8 weeks; the femoral trabecular micro-structure changes were observed in CIA rats by micro-CT; the LPS-induced osteoclasts model further observed the effect and mechanism of anti-inflammatory osteoporosis in vitro. The results indicated that MOIG could markedly increase bone mineral density (BMD) in CIA rats, improve trabecular micro-structure. In vitro studies demonstrated that MOIG could significantly inhibit osteoclastogensis and differentiation, suppress tartrate resistant acid phosphatase (TRAP) activity, F-actin ring formation, TNF receptor associated factor 6 (TRAF6) recruitment, and inhibitor of nuclear factor kappa-Bα (IκBα) degradation as well as p65 phosphorylation, thereby repressing nuclear factor kappa-B (NF-κB) signaling pathway activation. Subsequently, MOIG effectively inhibited osteoclast nuclear factor of activated T-cells c1 (NFATc1) and cellular oncogene Fos (c-Fos) expression, as well as bone resorption related protein activity including matrix metalloprotein 9 (MMP-9) and cathepsin K (CtsK). Meanwhile, MOIG also repressed the phosphorylation expression of Janus activating kinase 2 (JAK2) and signal transducer and activator of transcription 3 (STAT3), thereby inhibiting JAK2/STAT3 signaling pathway activation. Moreover, further studies found that MOIG could suppress glycogen synthase kinase-3β (GSK-3β) activity, and GSK-3β gene silencing could markedly inhibit oetsoclast F-actin ring formation as well as the phosphorylation expression of p65 and STAT3. Of note, compared with GSK-3β gene silencing group, there was no significant difference in the group treated with both MOIG with GSK-3β gene silencing simultaneously. Thus, the results suggested that MOIG may inhibit NF-κB signaling pathway and JAK2/STAT3 signaling pathway activation via regulating GSK-3β, thereby alleviating bone destruction in RA.

Objective To design a portable intelligent cleaner for medical lumen instruments to enhance cleaning efficiency.Methods The portable intelligent cleaner had a box-body shape and a shell made of 304 stainless steel,which was composed of a circuit control board,a micro pump,lithium batteries,a charging interface,a rinse tube and connectors.The circuit control board used a STM32G030C8T6 integraged circuit,which was equipped with a countdown digital tube to display the time left for cleaning;the micro pump and lithium batteries were placed at the inner wall of the box bottom,the charging interface and water inlet/outlet inteface were put on the outside of the front wall of the box bottom,the water inlet/outlet interface was connected with a silicon rinse tube linked to an adapter at its distal end,and the adapters with different calibers were compatible with sizes of medical lumen instruments.Totally 9 672 pieces of lumen instruments received by some hospital's disinfection supply center from May to October 2021 were divided into 2 groups with the convenience sampling method,with 4 836 pieces in each group.The odd-numbered instruments were enrolled into a control group and cleaned with an ultrasonic cleaner and a lumen brush,and the even-numbered instruments were included into an experimental group and cleaned conventionally after pretreatment by the intelligent cleaner.The two groups were compared in terms of eaning efficiency and satisfaction.Results Testing by visual inspection,magnifying glass with light source and white stripe method showed that the experimental group behaved better than the control group in the cleaning qualification rate,whose satisfaction rate(100％)was also higher than that of the control group(86.53％),with all the differences being statistically significant(P＜0.05).Conclusion The portable cleaner with easy operation enhances the cleaning quality and efficiency for medical lumen instruments.[Chinese Medical Equipment Journal,2024,45(10):114-117]

Purpose/Significance A prediction model is constructed based on real-world data to achieve prediction and early screening of type 2 diabetic microvascular complications.Method/Process Based on the real world data of Nanjing Drum Tower Hospital in the past 10 years,a particle swarm optimization based deep belief network(PSO-DBN)prediction model for microvascular complica-tions in type 2 diabetes mellitus is constructed by taking test results and medical record documents into consideration.Result/Conclusion The PSO-DBN model can predict diabetic microvascular complications,and the performance is better than that of random forest and sup-port vector machine(SVM)benchmark models,it provides references for the research of disease prediction model of real-world data.

Objective:To explore the application of COVID-19-specific IgG antibody in identifying epidemic Omicron BA.5 strain infection.Method:Omicron BF.7/BA.5 naturally infected population, healthy population vaccinated with the COVID-19 vaccine, and Omicron BF.7/BA.5 breakthrough cases were enrolled into this study. The serum WT-S-IgG and BA.5-S-IgG were detected by indirect ELISA, and the serum-specific IgG antibody levels of different populations were compared. The application value of the two antibody titers and the ratio of the two antibodies in identifying Omicron BA.5 epidemic strain infection were explored by the ROC curve, aiming to provide technical support for pathogen diagnosis.Results:The antibody titers of WT-S-IgG and BA.5-S-IgG in the breakthrough cases were higher than those in the naturally infected population and the healthy population ( P<0.05). The area under the curve (AUC) of WT-S-IgG and BA.5-S-IgG in identifying epidemic Omicron BA.5 strain infection was 0.947 and 0.961, respectively. The AUC of BA.5-S-IgG and WT-S-IgG antibody titer ratio was 0.873. When the antibody titer ratio was 0.855, the sensitivity and specificity were 80.00% and 90.00%, respectively. According to the interval since the last infection, the AUC of the ratio of BA.5-S-IgG to WT-S-IgG antibody titer to identify the infection of epidemic strains less than 30 days and more than 30 days was 0.887 and 0.863, respectively, and the sensitivity and specificity were both above 80%. Conclusion:Both BA.5-S-IgG and WT-S-IgG, as well as the combination of these two antibodies, are of high value in the identification of epidemic strains.

Objective To investigate the clinical efficacy of therapy of clearing heat,percolating dampness and lowering turbidity combined with Silibin Meglumine Tablets in the treatment of non-alcoholic steatohepatitis(NASH)patients with abnormal alanine aminotransferase(ALT)level of damp-heat accumulation type.Methods A retrospective study was conducted.According to the medication,80 patients with NASH with abnormal ALT level of damp-heat accumulation type were divided into control group and observation group,with 40 cases in each group.The control group was treated with Silibin Meglumine Tablets,and the observation group was treated with therapy of clearing heat,percolating dampness and lowering turbidity on the basis of treatment for the control group.The course of treatment covered 12 weeks.The changes of liver function indicators of ALT,aspartate aminotransferase(AST),and gamma glutamyl transpeptidase(GGT),blood lipid indicators of total cholesterol(CHOL)and triglyceride(TRIG),and the degree of hepatic steatosis in the two groups were observed before and after treatment.After treatment,the clinical efficacy and safety of the two groups were evaluated.Results(1)After 12 weeks of treatment,the total effective rate of the observation group was 95.00%(38/40),and that of the control group was 77.50%(31/40).The curative effect of the observation group was significantly superior to that of the control group,and the difference was statistically significant(P＜0.05).(2)After treatment,the levels of ALT,AST and GGT in the two groups were significantly lower than those before treatment(P＜0.05),and the decrease of ALT,AST and GGT in the observation group was significantly superior to that in the control group(P＜0.05).(3)After treatment,the levels of CHOL and TRIG in the two groups were significantly lower than those before treatment(P＜0.05),and the decrease of CHOL and TRIG in the observation group was significantly superior to that in the control group(P＜0.05).(4)After treatment,the degree of hepatic steatosis in the two groups was significantly lower than that before treatment(P＜0.05),and the decrease of the degree of hepatic steatosis in the observation group was significantly superior to that in the control group(P＜0.05).(5)During the treatment,no obvious adverse reactions occurred in the two groups,indicating high safety.Conclusion The therapy of clearing heat,percolating dampness and lowering turbidity combined with Silibin Meglumine Tablets exerts certain effect in the treatment of NASH patients with abnormal ALT level of damp-heat accumulation type,and the therapy can significantly enhance the clinical efficacy of Silibin Meglumine Tablets alone for NASH.

Objective To investigate the independent risk factors of comprehensive complication index(CCI)≥26.2 after radical resection of colon cancer,and use these factors to establish and verify a dynamic web-based nomogram model.Methods The clinical data of colon cancer patients who underwent radical resection in the Affiliated Hospital of Jiangnan University from November 2020 to April 2022 were retrospectively collected,and divided into main cohort(November 2020 to October 2021,n=438)and validation cohort(November 2021 to April 2022,n=196).CCI scores of all patients were obtained based on CCI calculator(http://www.assessurgery.com).Univariate and multivariate logistic regression analysis were performed to identify the risk factors for CCI≥26.2,and a nomogram model was constructed.Receiver operator characteristic curve(ROC),C index and calibration curve were used to evaluate the differentiation and consistency of predictive nomogram model,and the decision curve analysis was conducted to assess the clinical benefits of the model.Internal validation of the model is performed in the validation cohort.Results A total of 438 patients were identified in present study,of which 63 cases(14.4%)had CCI≥26.2.Multivariate logistic regression analysis revealed that age≥60 years(OR=2.662,95%CI 1.341-5.285,P=0.005),low third lumbar spine skeletal muscle mass index(L3MI;OR=4.572,95%CI 2.435-8.583,P<0.001),NRS2002≥3(OR=4.281,95%CI 2.304-7.952,P<0.001),and preoperative bowel obstruction(OR=3.785,95%CI 1.971-7.268,P<0.001)were significant independent risk factors for postoperative CCI≥26.2.Based on these results,a static and web-based dynamic nomogram was established(https://jndxfsyywcwksyf.shinyapps.io/DynNomCCI/).The C-index and area under the curve(AUC)of the nomogram were 0.742 and 0.787,respectively.The calibration curve indicated a good consistency between the predicted probability and the actual probability.In the validation cohort,the nomogram also presented good discrimination(C-index=0.722,AUC=0.795)and predictive consistency.The decision curve analysis indicated the clinical benefit and application value of the nomogram prediction model.Conclusion This easy-to-use dynamic nomogram based on 4 independent risk factors can conveniently and reliably predict the probability of CCI≥26.2 after radical resection of colon cancer,which helps optimize the preoperative evaluation system,formulate precise individualized treatment strategies,and enhance recovery after surgery.

Acute mitral regurgitation(MR)in the setting of myocardial infarction(MI)may be the result of papillary muscle rupture(PMR).The clinical presentation can be catastrophic,with refractory cardiogenic shock.This condition is associated with high morbidity and mortality.Transcatheter edge-to-edge repair(TEER)has become increasingly common in treating severe mitral regurgitation.This case details a successful TEER is feasible and safe in patients with acute MR following MI.TEER is an emerging treatment option in this clinical scenario that should be taken into consideration.