Background A diverse cohort of patients and susceptible individuals congregate in healthcare facilities, where exposure to pathogenic microorganisms associated with respiratory infectious diseases constitutes a significant risk factor for cross-infection. Central air-conditioning ventilation systems improve some indoor environment indicators while exacerbating the risk of transmission of respiratory infectious diseases. Objective To investigate the distribution characteristics of microbial communities in the central air-conditioning ventilation systems of hospitals, providing a scientific basis for the selection of microbial indicators in hygiene standards for hospital central air-conditioning ventilation systems and for hospital risk early warning systems. Methods In October 2023, two central air-conditioning ventilation systems were selected from a Grade 3A hospital in Shanghai: one was an all-air air-conditioning system serving the waiting area on the ground floor, and the other was a fan coil plus fresh air system serving the outpatient area on the third floor. Samples from four different components of the ventilation systems—air outlets, filters, surface coolers, and condensate trays—were collected for high-throughput sequencing of the 16S rRNA gene to analyze bacterial communities. Alpha-diversity and beta-diversity analyses were performed to investigate the microbial community composition and diversity characteristics of the hospital central air-conditioning ventilation systems. Functional analysis was conducted to determine the relative abundance of bacterial functions in these systems.Results A total of 528 operational taxonomic units (OTUs) were identified, encompassing 20 bacterial phyla, 37 classes, 79 orders, 123 families, and 240 genera. The analysis revealed that the bacterial community was predominantly composed of Proteobacteria, Gemmatimonadates, Bacteroidetes, and Actinobacteria. The diversity analysis indicated that bacterial community richness and diversity were highest in the condensate trays, while no statistically significant differences (P > 0.05) were observed in the bacterial community composition among the air outlets, filters, and surface coolers. The functional analysis showed that the bacterial communities in the central air-conditioning ventilation systems primarily exhibited chemoheterotrophic, oxidative energy-dependent heterotrophic, and ureolytic functional characteristics. Conclusion The dominance of Proteobacteria suggests that this phylum exhibits strong adaptability in the central air-conditioning ventilation systems, possibly related to its ability to survive and reproduce under varying environmental conditions. The diversity analysis indicates that the condensate tray is a critical area for bacterial proliferation in the central air-conditioning ventilation systems. The similarity in environmental conditions among the air outlets, filters, and surface coolers result in similar bacterial community structures. The functional analysis reveals that the bacterial communities possess robust energy conversion and metabolic capabilities, potentially contributing to processes such as organic matter decomposition and nitrogen cycling within the central air-conditioning ventilation systems.

In order to provide basic information for the utilization and development of famous classical formulas containing Bletillae Rhizoma， this article systematically analyzes the historical evolution of the name， origin， harvesting and processing of Bletillae Rhizoma by reviewing the ancient materia medica， prescription books， medical books and modern literature. The research results showed that Baiji（白及） was the main name， some scholars took Baiji（白芨） as its main name， and there were many other names such as Baiji（白给）， Baigen（白根）， Baiji（白苙）. The mainstream source of Bletillae Rhizoma was the tubers of Bletilla striata， and drying， large， white， solid， root-free and skin removed completely were the good quality standards. With the promotion of wild to cultivated medicinal materials， there were certain differences between their traits， and the quality evaluation indexes should be adjusted accordingly. The origin of records in the past dynasties was widely distributed， with Guizhou and Sichuan having high production and good quality in modern times. The harvesting period is mostly in spring and autumn， and harvested in autumn was better. The processing and processing technology is relatively simple， and it was used fresh or powdered in past dynasties， while it is mainly sliced for raw use in modern times. Based on the results， it is suggested that the tubers of Bletilla striata of Orchidaceae should be used in the famous classical formulas， and it should be uniformly written as Baiji（白及）. And if the original formula indicates the requirement of processing， it should be operated according to the requirement， if the requirement of processing is not indicated， it can be used in raw form as medicine.

ObjectiveTo investigate the effect of transplantation of bone marrow mesenchymal stem cells （BMSCs） co-cultured with bone marrow-derived M2 macrophages （M2-BMDMs）， named as BMSC^M2， on a rat model of liver cirrhosis induced by carbon tetrachloride （CCl₄）/2-acetaminofluorene （2-AAF）. MethodsRat BMDMs were isolated and polarized into M2 phenotype， and rat BMSCs were isolated and co-cultured with M2-BMDMs at the third generation to obtain BMSC^M2. The rats were given subcutaneous injection of CCl₄ for 6 weeks to establish a model of liver cirrhosis， and then they were randomly divided into model group （M group）， BMSC group， and BMSC^M2 group， with 6 rats in each group. A normal group （N group） with 6 rats was also established. Since week 7， the model rats were given 2-AAF by gavage in addition to the subcutaneous injection of CCl₄. Samples were collected at the end of week 10 to observe liver function， liver histopathology， and hydroxyproline （Hyp） content in liver tissue， as well as changes in the markers for hepatic stellate cells， hepatic progenitor cells， cholangiocytes， and hepatocytes. A one-way analysis of variance was used for comparison of continuous data between multiple groups， and the least significant difference t-test was used for further comparison between two groups. ResultsCompared with the N group， the M group had significant increases in the activities of serum alanine aminotransferase （ALT） and aspartate aminotransferase （AST） （P<0.01）； compared with the M group， the BMSC and BMSC^M2 groups had significant reductions in ALT and AST （P<0.01）， and the BMSC^M2 group had significantly better activities than the BMSC group （P<0.05）. Compared with the N group， the M group had significant increases in Hyp content and the mRNA and protein expression levels of alpha-smooth muscle actin （α-SMA） in the liver （P<0.01）； compared with the M group， the BMSC and BMSC^M2 groups had significant reductions in Hyp content and the expression of α-SMA （P<0.05）， and the BMSC^M2 group had a significantly lower level of α-SMA than the BMSC group （P<0.01）. Compared with the N group， the M group had significant increases in the mRNA expression levels of the hepatic progenitor cell markers EpCam and Sox9 and the cholangiocyte markers CK7 and CK19 （P<0.01） and significant reductions in the expression levels of the hepatocyte markers HNF-4α and Alb （P<0.01）； compared with the M group， the BMSC and BMSC^M2 groups had significant reductions in the mRNA expression levels of EpCam， Sox9， CK7， and CK19 （P<0.05） and significant increases in the mRNA expression levels of HNF-4α and Alb （P<0.05）， and compared with the BMSC group， the BMSC^M2 group had significant reductions in the mRNA expression levels of EpCam and CK19 （P<0.05） and significant increase in the expression level of HNF-4α （P<0.05）. ConclusionM2-BMDMs can enhance the therapeutic effect of BMSCs on CCl₄/2-AAF-induced liver cirrhosis in rats， which provides new ideas for further improving the therapeutic effect of BMSCs on liver cirrhosis.

Hepatocellular carcinoma （HCC） is the sixth most common cancer in the world. In recent years， the clinical early diagnosis and treatment protocols of HCC have been improved， whereas the prognosis of patients is still not satisfactory， which is due to the fact that the mechanism of HCC development has not been fully elucidated. Therefore， it is of great significance to explore the molecular mechanisms and key regulatory links of hepatocellular carcinoma development to further improve the diagnosis and treatment of HCC in China. Epigenetics has become a research hotspot because of its reversibility and easy regulation. According to relevant studies， HCC involves the accumulation of multiple genetic and epigenetic changes during the initiation， promotion， and progression stages. HCC is categorized as infantile malnutrition with accumulation， hypochondriac pain， tympan ites， and abdominal mass in traditional Chinese medicine （TCM）. In the treatment of HCC， TCM with low toxicity， multi-targets， and multi-mechanisms can inhibit tumor growth， alleviate the clinical symptoms， and enhance the quality of life of the patients. Chinese medicines and their active ingredients exert anti-HCC effects through epigenetic regulation of DNA methylation， histone modification， and non-coding RNA. Abnormal gene expression due to epigenetic regulation disorders is involved in all stages of HCC development. There are few studies on epigenetic regulation in TCM treatment of HCC， and there is still much room for development in basic and clinical trials. This paper reviews the mechanism of epigenetic regulation in HCC and summarizes the experimental results of TCM research on the related mechanism， with a view to providing a theoretical basis for future research on the mechanism of HCC development and clinical diagnosis and treatment of hepatocellular carcinoma with TCM.

Objective Endothelial injury plays a crucial role in forming deep vein thrombosis.This study aims to compare the effectiveness of various methods for creating rabbit femoral vein thrombotic models after the endothelial injuryso as to provide a solid experimental foundation for further research on the endothelial injury and deep vein thrombosis.Methods Forty-five rabbits were randomly divided into three groups(A,B,C),with 15 cases in each group and subjected to the endothelial injury using the methods of simple clamping,combined complete ligation,and combined incomplete ligation,respectively.The intravascular ultrasonic manifestations and local endothelial pathological changes were compared at 1,3,and 7 days after modeling.Results Significant differences in vascular diameter and Young's modulus values were observed after 7 days of modeling(P<0.05).In pairwise comparisons between the groups,the Young's modulus values in group C were significantly higher than those in groups A and B after 7 days of modeling(P<0.05).Pathological examination confirmed the presence of fibr-inoid thrombus in the blood vessels of group C on the seventh day of modeling.Conclusion Combining simple clam-ping and incomplete ligation can produce a relatively stable endothelial injury and thrombus formation.This method provides a robust experimental model for further investigation into deep vein thrombosis after the endothelial injury.

Objective:To investigate the current status of the teaching methods used in the integrated basic and clinical courses and the approaches for improving such teaching methods, and to improve the teaching quality of the integrated basic and clinical courses for "4+4" Medical Doctor Program in Peking Union Medical College.Methods:Students in the Class 2020 of "4+4" Medical Doctor Program who completed the integrated courses from September 2020 to August 2021 were enrolled as subjects. Questionnaire surveys and interviews were performed for the subjects in terms of class hours, integration effect, and self-learning methods. R4.0.0 software was used to perform a statistical analysis of data.Results:The mean weekly class hours of existing modules were (27.59±2.61) hours per week, which was higher than the expectation of students. There was a negative linear correlation between weekly class hours and mean satisfaction score of each module ( r=-0.71, P=0.022). The integration of basic and clinical medical courses had a mean satisfaction score of 2.652. The median preview time for case-based learning/problem-based learning was 30 minutes. Conclusions:In the reform of the integration of basic and clinical medical courses, it is crucial to select and apply proper teaching methods. In order to further improve teaching effect, it is advised to reduce the class hours of theoretical lectures and carefully design and prepare learning materials, and the teaching contents should be organized according to the internal logic of knowledge and the association between clinical knowledge and the knowledge learned during the stage of basic medicine.

Objective To evaluate the safety and effectiveness of excessive dynamic airway collapse(EDAC)treated by laser.Methods 13 patients with EDAC confirmed by bronchoscopy from January 2018 to August 2022 were selected and divided into a simple EDAC group(6 cases)and an EDAC combined with tracheobronchomalacia(TBM)group(7 cases)based on whether they were combined with TBM.All patients underwent laser tracheobronchoplasty under bronchoscope.Symptoms,airway collapse,oxygenation index,modified version of British Medical Research Council dyspnoea scale(mMRC)and 6 min walking test before and after treatment were compared to evaluate the therapeutic effect.Results 13 patients underwent 17 times of laser tracheobronchoplasty with laser power of 8～15 W,and 4 patients underwent 2 times of laser tracheobronchoplasty.After treatment,the clinical symptoms of cough,sputum,shortness of breath and dyspnea were improved in all patients.1 week post-treatment,the EDAC group showed a significant improvement in airway lumen stenosis,with a significant statistical difference(P<0.05),1 month post-treatment,enhancements were observed in airway stenosis,oxygenation index,FEV1%,6-minute walk test,and mMRC,which remained stable over a 6 month follow-up.In the EDAC + TBM group,significant enhancements in airway stenosis,oxygenation index,and mMRC were noted 1 week post-treatment,with statistical significance(P<0.05).Between 8 d～6 months post-treatment,some patients exhibited a recurrence of airway stenosis,necessitating comprehensive interventions like balloon dilation,cryotherapy,and stent insertion.Local necrosis and granuloma occurred in some patients after laser therapy,and no serious complications associated with laser intervention were found in all patients.Conclusion Laser tracheobronchoplasty is a safe and effective technique for the treatment of EDAC.For patients with EDAC alone,the therapeutic effect is good,but for patients with EDAC combined with TBM,the long-term effect is not good.

Objective To understand the awareness of the emergency physicians for thrombolytic thera-py recommended by ST-segment elevation myocardial infarction(STEMI)guidelines and implementation sit-uation,and to analyze the related influencing factors.Methods Relying on Chengdu Emergency Quality Con-trol Center,the questionnaires were distributed to the hospitals of expert group members and the hospitals of the medical union from April to July 2023 to investigate the awareness,implementation status and training status of the emergency doctors in Chengdu area on the STEMI thrombolytic therapy.The causes affecting thrombolysis decision-making were analyzed.Results A total of 137 hospitals participated in the survey.Whether the treatment system and type of chest pain,chest pain center,percutaneous coronary intervention(PCI)qualified hospitals or departments carrying out the training and hospital grade were correlated to whether STEMI patients were thrombolyzed within 12 h before transport(P＜0.05).Whether the PCI quali-fied hospital,chest pain center,chest pain treatment system and type,carrying training,hospital grade,geo-graphical location,transport duration,and thrombolytic indication understanding situation were not related to whether thrombolytic therapy was recommended for the duration from the first medical contact(FMC)to PCI(FMC-PCI)≥120 min(P＞0.05).The multivariate logistic regression analysis showed that whether the de-partment carrying out the training was an influential factor for whether thrombolytic therapy was carried out within 12 h before transport in STEMI onset(P＜0.05).The hospital grade was a influencing factor for whether thrombolysis in non-chest pain treatment system was carried before transport within 12 h of the onset of STEMI.The main reason for STEMI patients being directly transfered treatment without thrombolysis within 12 h of onset was because they knew that thrombolysis was needed but did not know how to do it(50.00％).The awareness rate of thrombolytic indication in non-main urban area was higher than that in main urban area(P＜0.05).The carrying out department training rate of PCI qualified hospitals was higher than that of non-PCI qualified hospitals(P＜0.05).The receiving superior hospital training rate also had difference among different hospital grades and geographical locations.Conclusion Conducting the thrombolysis training and enhancing the learning of treatment processes directly affect the emergency physicians'choice of reperfu-sion strategies for the patients with STEMI.Continuous promotion of the construction of chest pain center or chest pain treatment unit could further increase the early reperfusion rate of STEMI.

Objective To investigate the application effects of different myocardial protective solutions in total thoracoscopic minimally invasive aortic valve replacement surgery.Methods The clinical data of 72 patients with total thoracoscopic minimally invasive aortic valve replacement surgery in this hospital from May 2020 to January 2024 were analyzed retrospectively.The patients were divided into the St Thomas cardioplegia group(STH group,n=13),del Nido cardioplegia group(DN group,n=24),histidine tryptophan ketoglutar-ate solution group(HTK group,n=35)according to the different myocardial protective solutions.The levels of lactate(Lac)before and during surgery,the highest levels of myocardial creatine kinase isoenzyme(CK-MB),high-sensitivity troponin T(TnT)and creatinine(Cr)before operation,on the operative day and after surgery as well as the duration of extracorporeal circulation,aortic cross-clamping time,maximum flow rate,minimum bladder temperature,cardioplegia perfusion times,number of defibrillation after aortic de-clamping,postoperative ventilator assisted time,ICU stay duration and postoperative hospitalization duration were com-pared among the three groups.Results Except for 1 case of HTK was discharged automatically after surgery,the other 71 cases recovered and discharged according to the doctor's advice.There were no statistically signif-icant differences in the age,body weight,extracorporeal circulation time,aortic blocking time,maximum flow volume of extracorporeal circulation,minimum bladder temperature of extracorporeal circulation,Lac before extracorporeal circulation,highest Lac during extracorporeal circulation,assistant time of postoperative venti-lator,ICU stay duration,postoperative hospitalization duration,serum Cr before operation,Cr on operative day,preoperative TnT,postoperative TnT on operative day,postoperative highest TnT,preoperative CK-MB,postoperative CK-MB on operative day and postoperative highest CK-MB among the three groups(P＞0.05).There were statistically significant differences in the defibrillation ratio after aortic de-clamping and perfusion frequency of myocardial protective solution(P＜0.05).There was statistically significant difference in the perfusion frequency of myocardial protective solution in pairwise comparison among groups(P＜0.05),and the defibrillation ratio after aortic de-clamping had statistical difference between the DN group and HTK group(P＜0.05).Conclusion DN,STH and HTK all have good myocardial protective effect in total thoraco-scopic minimally invasive aortic valve surgery.HTK has the advantages of less perfusion times and decreasing the operative procedures compared with DN and STH;DN has the advantage of lower use for electrical defib-rillation correcting arrhythmias after aortic opening over HTK.

Objective This study aimed to identify PAX9 variants in non-syndromic tooth agenesis families of Chi-na,as well as to analyze the genotype-phenotype of non-syndromic tooth agenesis caused by PAX9 variants,which can provide a basis for the genetic diagnosis of tooth agenesis.Methods We collected the data of 44 patients with non-syn-dromic oligodontia who underwent treatment at Stomatological Hospital of Hebei Medical University between 2018 and 2023.Whole-exome sequencing was performed on the peripheral blood of the proband and its core family members,and the variants were verified by Sanger sequencing.Pathogenicity analysis and function prediction of the variants were per-formed using bioinformatics tools.The correlation between the genotype of PAX9 variant and its corresponding pheno-type was examined by reviewing 55 publications retrieved from PubMed.The studies involved 232 tooth agenesis pa-tients with PAX9 variants.Results A novel PAX9 c.447delG(p.Pro150Argfs*62)and a reported PAX9 c.406C>T(p.Gln136*)were identified in two Chinese families.Through bioinformatics analysis and three-dimensional structural mod-eling,we postulated that the frameshift variant was pathogenic.The outcome was the premature cessation of PAX9 pro-tein,which caused severe structural and functional deficiencies.Summarizing the PAX9 genotype-phenotype relationship revealed that patients carrying the PAX9 variant commonly led to loss of the second molars.Conclusion We identified the novel PAX9 c.447delG(p.Pro150Argfs*62)in a Chinese family of non-syndromic oligodontia,expanding the known variant spectrum of PAX9.The most susceptible tooth position for PAX9 variants of tooth agenesis was the second mo-lars and the deciduous molars during the deciduous dentition.