Virus-like particles(VLPs)are hollow nanoparticles composed of one or several virus structural proteins,which have a morphological structure similar to natural viruses but do not contain any genetic material.Due to the excellent innate immunogenicity and safety of VLPs,they are often used in the development of tumor vaccines.In addition,compared with traditional drug delivery vectors,VLPs have better biocompatibility and strong targeting ability,making them highly valued in the delivery of anti-tumor drugs.In recent years,the efficient delivery of gene editing tools using VLPs has provided new possibilities for tumor treatment.VLPs can inhibit tumor growth and spread through various mechanisms,such as activating immune responses to suppress tumor growth,stimulating the body's immune system,promoting the expression of tumor associated antigens,and enhancing the body's ability to recognize and clear tumor cells.These studies not only broaden the application scope of VLPs in the field of anti-tumor therapy,but also provide a broader prospect for future research and application.This article reviewed the research progress of VLPs derived from different viruses in preventive or therapeutic vaccines and drug delivery carriers,and explored new development strategies.

Objective:To explore the potential influencing factors of parenteral nutrition-associated cholestasis（PNAC）in extremely premature infants.Methods:A total of 83 cases of extremely premature infants who received parenteral nutrition and developed PNAC admitted to Shanxi Children's Hospital between October 2020 and October 2023 were selected as the case group，while 99 extremely premature infants who received parenteral nutrition but did not develop PNAC during the same period were selected as the control group. Basic information such as gender，gestational age，birth weight，and duration of parenteral nutrition were collected for the extremely premature infants. The health status of the infants at 1 minute and 5 minutes after birth was assessed using the Apgar standardized scoring method. One week after parenteral nutrition,platelet count(PLC)，mean platelet volume(MPV)，and platelet volume distribution width(PDW) were measured. Univariate analysis and non-conditional Logistic regression were used to analyze the potential influencing factors of PNAC in extremely premature infants after parenteral nutrition. Receiver operating characteristic(ROC) curves were plotted to evaluate the performance of the influencing factors and combined predictive factors in predicting PNAC in extremely premature infants receiving parenteral nutrition.Results:The 1-min and 5-min Apgar scores in the case group were lower than those in the control group( P<0.001);the percentages of gestational hypertension in mothers and postnatal infections in children were higher than those in the control group( P<0.05);and the duration of parenteral nutrition was longer than that in the control group( t=4.655, P<0.001), the differences were statistically significant. In the case group, after one week of parenteral nutrition,PLC was lower than that in the control group( t=4.949, P<0.001),MPV was higher than that in the control group( t=12.193, P<0.001), and PDW was higher than that in the control group( t=10.744, P<0.001), the differences were statistically significant.Multifactorial Logistic analysis showed that after adjusting for gender and gestational age，1-minute Apgar score（ OR=0.898），5-minute Apgar score（ OR=0.900），postnatal infection（ OR=1.256），duration of parenteral nutrition（ OR=1.426），one week after parenteral nutrition，PLC（ OR=0.902），MPV（ OR=1.441），and PDW（ OR=1.195）were independent influencing factors for PNAC in extremely premature infants（all P<0.05）. ROC curves showed that each factor and combined predictive factors had certain efficacy in predicting the occurrence of PNAC in extremely premature infants after parenteral nutrition. Conclusion:One-minute Apgar score,5-minute Apgar score，duration of parenteral nutrition，postnatal infection，one week after parenteral nutrition，the PLC,MPV and PDW are independent influencing factors for PNAC in extremely premature infants receiving parenteral nutrition.Each factor predicts the efficacy of parenteral nutrition for PNAC in extremely premature infants, and relevant factors should be controlled in time to reduce the incidence of PNAC in extremely premature infants.

Virus-like particles(VLPs)are hollow nanoparticles composed of one or several virus structural proteins,which have a morphological structure similar to natural viruses but do not contain any genetic material.Due to the excellent innate immunogenicity and safety of VLPs,they are often used in the development of tumor vaccines.In addition,compared with traditional drug delivery vectors,VLPs have better biocompatibility and strong targeting ability,making them highly valued in the delivery of anti-tumor drugs.In recent years,the efficient delivery of gene editing tools using VLPs has provided new possibilities for tumor treatment.VLPs can inhibit tumor growth and spread through various mechanisms,such as activating immune responses to suppress tumor growth,stimulating the body's immune system,promoting the expression of tumor associated antigens,and enhancing the body's ability to recognize and clear tumor cells.These studies not only broaden the application scope of VLPs in the field of anti-tumor therapy,but also provide a broader prospect for future research and application.This article reviewed the research progress of VLPs derived from different viruses in preventive or therapeutic vaccines and drug delivery carriers,and explored new development strategies.

Objective To compare the effectiveness of cobalt chloride test papers and borescope in evaluating the drying of endoscopes,providing a reference for clinical selection of appropriate assessment tools.Methods 10 gastroscopes and 10 colonoscopes procedures were selected from November 2023 to March 2024 for circulation experiments.After endoscope reprocessing,they were randomly divided into five groups with different drying times(30 s,3 min,6 min,9 min,and 12 min)with 200 samples.Cobalt chloride test paper and borescope were used to evaluate the drying effectiveness.Results The qualified rate of gastrointestinal endoscope by borescope was significantly higher than that by cobalt chloride test paper,but cobalt chloride test paper was obviously better than that by borescope in convenience and cost-effectiveness.The borescope had the function of visualization,and the quantitative positioning observation of residual droplets showed that there were a large number of droplets left after gastrointestinal endoscope drying for 30 s,and the number of droplets was obviously reduced after drying for 3 min.Among them,the gastroscope was mainly light(1～5 drops/strip)and none(0 drops/strip),and the colonoscope was mainly moderate(6～10 drops/strip)and light droplets.Compared with different drying times,there was a significant statistical difference in the number of residual droplets in the endoscope(P<0.01),and the localized droplets mainly remained in the distal bending part and the proximal bifurcation part of the lumen.Conclusion Both cobalt chloride test papers and borescope are important methods for assessing endoscope drying efficacy,each with its own advantages and limitations.Clinicians can use both methods in combination to comprehensively evaluate the overall dryness of endoscopes,thereby ensuring the safety and effectiveness of the endoscope reprocessing process.

Objective:This study aims to investigate the feasibility and safety of implanting leadless pacemakers in the low septum and its impact on cardiac electrical synchronization.Methods:A total of 36 patients who received leadless pacemaker implantation at Fuwai Central China Cardiovascular Hospital from January 2021 to August 2023 were included in this study.According to implantation sites of leadless pacemakers,patients were divided into mid-septal group(n=16)and low-septal group(n=20).The clinical characteristics and cardiac electrical synchronization were compared between the two groups.Results:There were 21 male patients,mean age was(68±13)years old.There was no statistical difference in the type of brady-arrhythmia between the two groups(P=0.73).There were 61 implant attempts in these 36 patients,and there was no significant difference in the number of attempts,procedure time,and pacemaker parameters between the two groups,but the average procedure time tended to be shorter in the low-septal group([84±37]minutes vs.[105±35]minutes,P=0.09).In terms of electrical synchronization,there was no statistical difference in QRS duration between the low-septal group and the mid-septal group([162.0±21.1]ms vs.[174.0±14.8]ms,P=0.20).There were no vascular puncture complications,cardiac perforation,or pericardial tamponade during the procedure.There were no complications and readmissions related to the leadless pacemaker during follow-up period.Conclusions:Our results show that the implantation of a leadless pacemaker in the low ventricular septum is safe and effective,has a similar impact on cardiac electrical synchronization as mid-septal pacing.

At present,malignant tumor diseases occur frequently and increase year by year.Traditional chemoradiotherapy methods are expensive,have serious toxic and side effects,and are easy to reduce patient tolerance.Natural medicines have advantages of multiple targets,high selectivity and low toxicity and side effects in process of anti-tumor,and are one of important sources of anti-tumor drugs.As a polypeptide substance,lactoferrin has a strong anti-tumor effect and plays a huge role in field of nano-drug delivery.Receptors of lactoferrin are widely expressed on surface of various cancer cells.In addition to its strong anti-tumor effect,it is also widely used to modify nanocarriers.In this paper,anti-tumor mechanism of lactoferrin is reviewed,and the latest research progress of using lactoferrin as an anti-cancer drug delivery carrier is also introduced.

Objective To investigate the bacterial contamination of water specimens at different pre-discharge time of flexible endoscopic final rinse water before daily use,and provide reference basis for choosing the optimal pre-dis-charge time in clinical work.Methods From August to December 2023,the water produced by the purified water equipment of the digestive endoscopy centers of 4 tertiary first-class medical institutions in Jiangxi Province,as well as the final rinsing water at the terminal-point at different pre-discharge times(before pre-discharge,discharge of 1,3,5,and 10 minutes)were subjected to on-site sampling,the collected water specimens were performed microbio-logical cultures by pouring and filter membrane methods,unqualified water specimens were performed bacterial i-dentification.Results 48 specimens of water produced by purified water equipment were collected,with qualified rate of 100％.480 final water specimens were collected,with a qualified rate of 0 before pre-discharge.The quali-fied rates of pre-discharge at 1,3,5,and 10 minutes were 0,21.88％,55.21％,and 73.96％,respectively.Bac-terial colony counts in the final rinse water with different pre-discharge times in 4 medical institutions showed statis-tically significant differences(all P＜0.001).As the pre-discharge time increased,bacterial colony counts in the fi-nal rinse water of all four medical institutions showed a decreasing trend.The pairwise comparison of the overall bacterial colony count of the final rinse water at different pre-discharge time showed that there was no statistically significant difference in the bacterial colony count of the final rinse water at 5 and 10 minutes of pre-discharge(P＞0.05),while the pairwise comparison between other time points showed statistically significant differences(all P＜0.001).Environmental contaminated bacteria such as Micrococcus luteus,Cupriavidus paucula,and Sphin-gononas paucimobilis were detected from the unqualified water specimens.Conclusion With the extension of pre-discharge time,the degree of bacterial contamination in the final rinse water significantly decreases.All levels of medical institutions need to pre-discharge the final rinse water daily,and the pre-discharge time should last for at least 5 minutes.

Objectives:This study aims to explore the impact of new-onset heart conduction block post transcatheter aortic valve replacement(TAVR)on the cardiac conduction status during 1-year follow-up.Methods:A total of 130 patients who completed TAVR surgery at Fuwai Central-China Cardiovascular Hospital from July 2019 to October 2022 were screened.Among them,56 cases with postoperative heart conduction block were selected for analysis.According to the degree of heart block,patients were divided into mild block group(n=36),moderate block group(n=9),and severe block group(n=11).The clinical characteristics and cardiac conduction conditions at 1-year follow-up between different groups were compared.Results:During a mean(8.5±4.1)months follow-up period,10(17.9%)patients had long-term atrioventricular conduction block,and 46(82.1%)patients had partial or complete recovery of heart block,with 28(50.0%)patients with completely recovered cardiac conduction.In the mild block group,22(61.1%)cases were completely recovered,9(25.0%)patients partly recovered,and 5(13.9%)cases uncovered.In the moderate block group,2(22.2%)cases were completely recovered,5(55.6%)patients partly recovered,and 2(22.2%)cases uncovered.Difference in long-term atrioventricular conduction block among three groups was statistically significant(P<0.001).The Kaplan-Meier curve shows that patients with moderate to severe heart block have a higher rate of long-term atrioventricular conduction block(86.1%vs.77.8%vs.72.7%,log-rank P=0.03).Cox multivariate analysis exhibited that old age(≥75 years old,HR=1.204,95%CI:1.051-1.525,P=0.041)and severe heart conduction block(HR=1.106,95%CI:1.100-1.616,P=0.031)are the two independent risk factors for long-term atrioventricular conduction block post TAVR.Conclusions:The ratio of complete cardiac conduction recovery post TAVR is 50.0%.Older age(≥75 year)and new-onset severe heart conduction block are independent risk factors for long-term atrioventricular conduction block post TAVR procedure.

Objective:To explore the potential influencing factors of parenteral nutrition-associated cholestasis（PNAC）in extremely premature infants.Methods:A total of 83 cases of extremely premature infants who received parenteral nutrition and developed PNAC admitted to Shanxi Children's Hospital between October 2020 and October 2023 were selected as the case group，while 99 extremely premature infants who received parenteral nutrition but did not develop PNAC during the same period were selected as the control group. Basic information such as gender，gestational age，birth weight，and duration of parenteral nutrition were collected for the extremely premature infants. The health status of the infants at 1 minute and 5 minutes after birth was assessed using the Apgar standardized scoring method. One week after parenteral nutrition,platelet count(PLC)，mean platelet volume(MPV)，and platelet volume distribution width(PDW) were measured. Univariate analysis and non-conditional Logistic regression were used to analyze the potential influencing factors of PNAC in extremely premature infants after parenteral nutrition. Receiver operating characteristic(ROC) curves were plotted to evaluate the performance of the influencing factors and combined predictive factors in predicting PNAC in extremely premature infants receiving parenteral nutrition.Results:The 1-min and 5-min Apgar scores in the case group were lower than those in the control group( P<0.001);the percentages of gestational hypertension in mothers and postnatal infections in children were higher than those in the control group( P<0.05);and the duration of parenteral nutrition was longer than that in the control group( t=4.655, P<0.001), the differences were statistically significant. In the case group, after one week of parenteral nutrition,PLC was lower than that in the control group( t=4.949, P<0.001),MPV was higher than that in the control group( t=12.193, P<0.001), and PDW was higher than that in the control group( t=10.744, P<0.001), the differences were statistically significant.Multifactorial Logistic analysis showed that after adjusting for gender and gestational age，1-minute Apgar score（ OR=0.898），5-minute Apgar score（ OR=0.900），postnatal infection（ OR=1.256），duration of parenteral nutrition（ OR=1.426），one week after parenteral nutrition，PLC（ OR=0.902），MPV（ OR=1.441），and PDW（ OR=1.195）were independent influencing factors for PNAC in extremely premature infants（all P<0.05）. ROC curves showed that each factor and combined predictive factors had certain efficacy in predicting the occurrence of PNAC in extremely premature infants after parenteral nutrition. Conclusion:One-minute Apgar score,5-minute Apgar score，duration of parenteral nutrition，postnatal infection，one week after parenteral nutrition，the PLC,MPV and PDW are independent influencing factors for PNAC in extremely premature infants receiving parenteral nutrition.Each factor predicts the efficacy of parenteral nutrition for PNAC in extremely premature infants, and relevant factors should be controlled in time to reduce the incidence of PNAC in extremely premature infants.

Objective To understand the current status of application,management,and maintenance of automa-ted endoscope reprocessors(AERs)in China.Methods A questionnaire survey was conducted using convenience sampling method on the application,management,maintenance,and monitoring of AERs,as well as personnel training in digestive endoscopy centers of 292 medical institutions(MIs).Results A total of 316 questionnaires were distributed,and 292 were available,with an effective response rate of 92.41％.Among the 292 MIs,198(67.81％)were equipped with AERs,with equipment rates of 75.11％in tertiary MIs and 41.27％in secondary MIs.88.38％of MIs performed manual cleaning before placing endoscopes into AERs,while 2.02％of MIs still didn't perform this step,mainly in tertiary MIs.The most common problems in the application of AERs were the detachment or damage of connecting pipes(83.33％),followed by disinfectant leakage of AERs(43.94％),mal-function of control panel(43.94％),and failure or poor water flow of AER pipeline(42.93％).92.42％of MIs regularly disinfected AERs,72.73％of MIs regularly replaced AER air filters,and 80.30％of MIs regularly re-placed AER water filters.96.46％of MIs monitored the concentration of disinfectants before daily application of AERs,87.88％of MIs regularly monitored the final rinse water of AERs,and 96.97％of MIs provided professio-nal training for new employees to use AERs for the first time.Conclusion The equipping rate of AERs at all levels of MIs in China still needs to be improved.Most MIs are able to monitor and maintain AERs well,but there are still many problems in the application process.Due to the large volume of endoscopic diagnosis and treatment as well as insufficient execution rate of manual cleaning in tertiary MIs,it is necessary to optimize workflow and strengthen training.Secondary MIs face challenges such as equipment shortages and low monitoring execution rates,requiring increased funding and regulatory efforts.It is recommended that manufacturers continuously optimize AER design,MIs establish standardized AER application protocol,and relevant departments improve AER application and ma-nagement standards,in order to improve the quality of endoscopic cleaning and disinfection and ensure patient safety during diagnosis and treatment.