BACKGROUND:Quercetin plays an important role in the proliferation and differentiation of bone marrow mesenchymal stem cells,but less research has been done on its mechanism of promoting the migration of bone marrow mesenchymal stem cells. OBJECTIVE:To study the effect of quercetin on the migration of human bone marrow mesenchymal stem cells through in vitro experiments,and to explore the regulatory role of CCR1 and CXCR4. METHODS:Human bone marrow mesenchymal stem cells were selected as experimental subjects.CCK8 assay was used to detect the effect of quercetin on the proliferative activity of human bone marrow mesenchymal stem cells.Cell scratch assay and Transwell assay were used to detect the in vitro invasive and migratory abilities of human bone marrow mesenchymal stem cells after quercetin treatment,respectively.The role of quercetin in relation to CCR1 and CXCR4 was demonstrated with the help of molecular docking technology.Western blot assay and real-time fluorescence quantitative PCR were used to detect the migration-related chemokine expression after quercetin treatment. RESULTS AND CONCLUSION:(1)5 and 10 μmol/L quercetin could significantly promote the proliferation of human bone marrow mesenchymal stem cells,and the drug concentration of 10 μmol/L resulted in the highest cell proliferation efficiency.(2)To better explore the dose-effect relationship of quercetin affecting the migration of human bone marrow mesenchymal stem cells,5 and 10 μmol/L quercetin were selected for the subsequent experiments,and ligustrazine was used as the positive control drug,and the experiments were divided into blank control group,5 μmol/L quercetin group,10 μmol/L quercetin group,and 100 μmol/L ligustrazine group.(3)In vitro migration and invasion ability of human bone marrow mesenchymal stem cells were elevated in a concentration-dependent manner after quercetin treatment,and the migration effect of 10 μmol/L quercetin group was better than that of ligustrazine group.(4)The molecular docking results suggested that there was a strong interaction between quercetin and CCR1 and CXCR4.(5)Quercetin could up-regulate the expression of CCR1 and CXCR4 proteins and mRNA.(6)This study confirmed at the cellular level that quercetin could promote the migration of human bone marrow mesenchymal stem cells by targeting CCR1 and CXCR4.

This study was aimed at performing epidemiologic investigation of the first psittacosis death case in Hangzhou City,to provide a reference for the investigation and disposal of psittacosis cases,as well as prevention and control.Epidemio-logic data were collected through field epidemiologic investigation,and close contacts and environmental samples were collected for pathogenicity testing.The first symptom in the patient was cough,which did not raise concerns at the time.Several days later,the patient developed abdominal distension and black stools,and visited two medical institutions for treatment and hospi-talization.The patient's sputum and peripheral blood were tested for Chlamydia psittaci infection by metagenomic analysis via next-generation sequencing.Samples collected from the patient's family members,close contacts,and home environment test-ed negative with real-time quantitative polymerase chain reaction.The patient later died of gastrointestinal bleeding.This article is the first report of a case of psittacosis contracted from exposure to a sick parrot in Hangzhou City,in a patient who died be-cause of an underlying disease.Operational training should be provided for medical personnel,and early diagnosis with mNGS and treatment of patients with underlying diseases should be performed as early as possible to avoid fatality.In addition,health education should be carried out to raise public awareness of the disease.

Objective To study the inhibitory effect of Huidu Yinhua powder from the Orthodox Manual of External Medicine on methicillin-resistant Staphylococcus aureus(MRSA),virulence factor α-hemolysin(Hla)activity,and biofilm formation,and to explore the optimal ratios of Huidu Yinhua powder and provide experimental support for its use.Methods The inhibitory effects of Huidu Yinhua powder and the herbs in the formula on USA300 were analyzed by the minimum inhibitory concentration(MIC),minimum bactericidal concentration(MBC),and disk diffusion assay(K-B method).Hemolysis,neutralization,oligomerization,and Western blot assays were used to verify in which form the drug inhibits the activity of virulence factor α-hemolysin(Hla).A biofilm assay was performed to evaluate the inhibitory effect of Huidu Yinhua powder on biofilm.Orthogonal experiments were performed to explore the optimal ratio of Huidu Yinhua powder.Results Huidu Yinhua powder inhibited the MRSA strain with a MIC90 of 64 mg/mL and an MBC of 256 mg/mL with antibacterial circle diameter of(7.50±0.50)mm.Huidu Yinhua powder inhibited Hla activity by inhibiting Hla secretion.The minimum effective concentration(MEC)was 16 mg/mL,and the MEC of biofilm was 8 mg/mL.In Huidu Yinhua powder,honeysuckle and astragalus only affected the hemolytic activity of MRSA and biofilm formation without inhibiting bacterial growth.The hemolytic activity and biofilm of MEC were both 32 mg/mL.Glycyrrhiza had a strong bacterial inhibitory capacity with a MIC90 of 8 mg/mL and biofilm MEC of 1 mg/mL without showing inhibitory hemolytic activity at subinhibitory concentrations.The orthogonal experiment showed that,at a ratio of honeysuckle,astragalus,and glycyrrhiza in Huidu Yinhua powder of 1∶2∶4,the MIC90 was 16 mg/mL,MEC of hemolytic activity was 8 mg/mL and that of biofilm was 4 mg/mL,both of which were the lowest among the nine groups.Conclusions Huidu Yinhua powder affects the hemolytic activity and biofilm formation of MRSA at subinhibitory concentrations with the optimal ratio of honeysuckle,astragalus,and glycyrrhiza being 1∶2∶4.

Objective:This study aims to analyze the clinical characteristics of elderly patients with lung adenocarcinoma and to construct a predictive model for assessing their survival.Methods:We conducted a retrospective analysis of clinical data sourced from the SEER database for patients aged 60 years or older who were diagnosed with lung adenocarcinoma between 2013 and 2018.Cox regression analysis was employed to identify independent prognostic factors affecting the survival of elderly lung adenocarcinoma patients, leading to the development of a nomogram model.The discriminative ability and calibration of the nomogram were assessed using the C-index and calibration curve.Each patient's total risk score was calculated based on the predictive model, and patients were stratified according to the quartiles of their total risk scores.The Kaplan-Meier method and Log-rank test were utilized to evaluate survival differences among the identified risk groups.Results:Among 38, 852 lung adenocarcinoma patients, 17, 200 were males and 21, 652 were females.Significant differences in survival rates were observed among lung adenocarcinoma patients based on age, gender, marital status, histological grade, TNM stage, tumor size, and the presence of bone, brain, or liver metastases, as well as the type of treatment received, including surgical treatment, radiation therapy, and chemotherapy(all P<0.001).The C-index of the training model was 0.815(95% CI: 0.811-0.819), while the validation model yielded a C-index of 0.810(95% CI: 0.804-0.816).The prediction model demonstrated higher Area Under Curve(AUC)values of 0.746, 0.768, and 0.775 for 1-year, 3-year, and 5-year survival in the modeling dataset, respectively, and 0.747, 0.770, and 0.777 in the validation dataset.Furthermore, the risk stratification model effectively distinguished patients at varying levels of risk( P<0.001). Conclusions:Age, gender, marital status, histological grade, TNM stage, tumor size, and the presence of bone, brain, and liver metastases, along with treatment modalities such as surgery, radiotherapy, and chemotherapy, were identified as independent prognostic factors for elderly patients with lung adenocarcinoma.The risk prediction model developed in this study effectively differentiates between patients at varying levels of risk, which holds significant implications for predicting treatment responses in elderly lung adenocarcinoma patients and advancing the practice of precision medicine.

In order to solve the problem of resistance of Pseudomonas aeruginosa to multiple antibiotics, it is an effective way to find inhibitors of P. aeruginosa efflux pump. In this study, 15 new ornithine peptidomimetic derivatives were designed and synthesized by changing the side chain structure of natural amino acids with PAβN, a dipeptide efflux pump inhibitor, and their synergic activity with aztreonam, a monocyclic β-lactam antibiotic, against P. aeruginosa was evaluated. Among them, the representative compound 12b not only enhanced the antibacterial activity of β-lactam antibiotics aztreonam, ceftazidime and meropenem, but also significantly enhanced the antibacterial action of macrolide antibiotics clarithromycin, showing a broad-spectrum synergic sensitization effect. In addition, compound 12b also has a good safety. Preliminary mechanisms suggest that 12b works by directly targeting the efflux transporter MexB. These results provide a new lead compound for the development of a new class of efflux pump inhibitors against P. aeruginosa.

Objective To investigate the clinical characteristics of empyema caused by Streptococcus anginosus (SA).Methods The clinical data in 9 cases of SA caused empyema admitted and treated in the First Affiliated Hospital of Xi'an Medical University from January 2016 to September 2023 were analyzed ret-rospectively,summarized the clinical characteristics of empyema caused by SA.Results Among 9 patients,there were 8 males and 1 female,with a mean age of (60.8±12.8)years old.All patients had the underlying diseases,meanwhile were accompanied by fever,expectoration,chest pain and dyspnea.The onset time was (6.1±2.2)d.The hospitalization time was (19.33±7.48)d.All patients showed the increase in white blood cells (WBC),C reactive protein (CRP),procalcitonin (PCT),D-dimer (D-D) and pleural effusion lactic dehy-drogenase (LDH),and decrease in blood albumin (ALB) and pleural effusion glucose (GLU).Most of the pa-tients had elevation of adenosine deaminase (ADA) in pleural fluid.Four patients had respiratory failure.The drug sensitivity test results of pleural effusion culture suggested five patients were resistant to erythromycin and clindamycin.One patient was resistant to ceftriaxone.Nine patients were improved after symptomatic treatment such as anti-infection,closed thoracic drainage and nutritional support.Conclusion The patients with SA caused empye-ma are more common in elderly patients with underlying diseases.The incubation period is short,the hospital stay is long,the infection indexes are high,malnutrition exists,and the resistance rate to erythromycin and clindamycin is high.

Objective To analyze the antimicrobial susceptibility,molecular types,serotypes,virulence factors and resistance mechanisms of Streptococcus agalactiae(S.agalactiae)isolated from pregnant women with ad-vanced maternal age in Tangshan City,and provide basic data for the treatment,prevention and control of S.aga-lactiae infection.Methods 42 strains of S.agalactiae isolated from pregnant women with advanced maternal age in North China University of Science and Technology Affiliated Hospital as well as Tangshan Maternal and Child Health Hospital were collected.Detection of antimicrobial susceptibility and whole genome sequencing of 13 antimi-crobial agents were performed.Results The percentage of tetracycline,erythromycin,levofloxacin,and chloram-phenicol concurrently resistant strains was 7.1％,35.7％of the strains presented multidrug resistance to erythro-mycin,clindamycin,and levofloxacin.The carriage rates of resistance genes ermB and tetM were 66.7％and 47.6％,respectively.29 strains(69.0％)exhibited mutations in both gyrA and parC fluoroquinolone resistance determi-nants.42 strains of S.agalactiae belonged to 4 serotypes,namely ⅠB(35.7％),Ⅲ(33.3％),Ⅴ(26.2％),andⅠA(4.8％);and 11 sequence types(STs),with the highest proportion being ST10(35.7％)and ST19(31.0％);as well as 6 clonal complexes(CCs),among which CC19(42.9％)and CC12(35.7％)had the highest proportion.All S.agalactiae carried virulence factor-encoding genes of cfb,cylE,and pavA.Conclusion The molecular types and serotypes of S.agalactiae carried by pregnant women with advanced maternal age in Tangshan City pre-sent polymorphism,with obvious multidrug resistance,and carry multiple types of drug resistance genes and viru-lence genes.

With the widespread adoption of technologies such as diagnostic imaging, interventional medicine, radiotherapy, and nuclear medicine, a growing number of people are exposed to low-dose ionizing radiation. Currently, the biological effects of low-dose radiation remain unclear, necessitating the identification of sensitive and specific biomarkers for risk assessment and health monitoring of such exposure. In this paper, we review the latest research progress in low-dose ionizing radiation biomarkers from the five perspectives of cytogenetics, DNA damage, transcriptome, proteome, and metabolomics. This review aims to provide a theoretical basis for the study of the biological effects of low-dose radiation.

Background/Aims: The histological characteristics and natural history of precirrhotic primary biliary cholangitis (PBC) with portal hypertension (PH) are unclear. Our aim was to clarify the prevalence, risk factors, and histological characteristics of precirrhotic PBC patients with PH. Methods: This retrospective study compared the clinical features, histological characteristics, and response to ursodeoxycholic acid (UDCA) between the PH and non-PH groups of precirrhotic PBC patients. Results: Out of 165 precirrhotic PBC patients, 40 (24.2%) also had PH. According to histological stage 1, 2 and 3 disease, 5.3% (1/19), 17.3% (17/98), and 45.8% (22/48) of patients also had PH, respectively. Precirrhotic PBC with PH was significantly positively correlated with bile duct loss, degree of cytokeratin 7 positivity, and degree of fibrosis in the portal area, but significantly negatively correlated with lymphoid follicular aggregation. Compared to the non-PH group, patients in the PH group showed a higher prevalence of obliterative portal venopathy, incomplete septal fibrosis, portal tract abnormalities and non-zonal sinusoidal dilatation (p<0.05). In addition, patients with PH were more likely to present with symptoms of jaundice, ascites, epigastric discomfort, a poorer response to UDCA, and more decompensation events (p<0.05). High alkaline phosphatase levels, low white blood cell counts, high Mayo scores, and high FIB-4 index values were risk factors for precirrhotic PBC with PH. Conclusions Approximately 24.2% of precirrhotic PBC patients have PH, which is histologically related to the injury of bile ducts. High alkaline phosphatase levels, low white blood cell counts, high Mayo scores, and high FIB-4 index values are associated with increased risk of precirrhotic PBC with PH.

Objectives: . Branchio-oto syndrome (BOS) primarily manifests as hearing loss, preauricular pits, and branchial defects. EYA1 is the most common pathogenic gene, and splicing mutations account for a substantial proportion of cases. However, few studies have addressed the structural changes in the protein caused by splicing mutations and potential pathogenic factors, and several studies have shown that middle-ear surgery has limited effectiveness in improving hearing in these patients. BOS has also been relatively infrequently reported in the Chinese population. This study explored the genetic etiology in the family of a proband with BOS and provided clinical treatment to improve the patient’s hearing. Methods: . We collected detailed clinical features and peripheral blood samples from the patients and unaffected individuals within the family. Pathogenic mutations were identified by whole-exome sequencing and cosegregation analysis and classified according to the American College of Medical Genetics and Genomics guidelines. Alternative splicing was verified through a minigene assay. The predicted three-dimensional protein structure and biochemical experiments were used to investigate the pathogenicity of the mutation. The proband underwent middle-ear surgery and was followed up at 1 month and 6 months postoperatively to monitor auditory improvement. Results: . A novel heterozygous EYA1 splicing variant (c.1050+4 A>C) was identified and classified as pathogenic (PVS1(RNA), PM2, PP1). Skipping of exon 11 of the EYA1 pre-mRNA was confirmed using a minigene assay. This mutation may impair EYA1-SIX1 interactions, as shown by an immunoprecipitation assay. The EYA1-Mut protein exhibited cellular mislocalization and decreased protein expression in cytological experiments. Middle-ear surgery significantly improved hearing loss caused by bone-conduction abnormalities in the proband. Conclusion . We reported a novel splicing variant of EYA1 in a Chinese family with BOS and revealed the potential molecular pathogenic mechanism. The significant hearing improvement observed in the proband after middle-ear surgery provides a reference for auditory rehabilitation in similar patients.