Objective:To construct a nanoparticle vaccine displaying the prefusion F (preF) protein of respiratory syncytial virus (RSV) using the I53-50 protein nanoparticle platform, and to systematically evaluate its immunogenicity and protective efficacy.Methods:The RSV preF trimer antigen was genetically fused to I53-50A and assembled in vitro with I53-50B to form preF-I53-50 nanoparticles, theoretically displaying 20 preF antigens per particle. The structure and purity were characterized by size-exclusion chromatography, SDS-PAGE, and negative-stain electron microscopy. BALB/c mice were intramuscularly immunized with varying doses (1 μg or 5 μg) of preF antigen or an equimolar amount of preF-I53-50 nanoparticles. Humoral immunity, B-cell responses, and protective efficacy were assessed following intranasal viral challenge.Results:The preF-I53-50 nanoparticles self-assembled into spherical structures (50-60 nm in diameter) with uniformly arrayed antigens. The nanoparticle vaccine enhanced RSV-specific IgG1 and IgG2a antibody responses, promoting a Th1-biased immune profile. At equimolar preF doses, the neutralizing antibody titers induced by 1 μg and 5 μg nanoparticle formulations were 2.8-fold and 2.3-fold higher, respectively, than those elicited by preF alone ( P<0.05). Notably, even the low-dose nanoparticle group outperformed the high-dose preF group (1.6-fold increase). Viral challenge experiments demonstrated that preF-I53-50 effectively suppressed pulmonary viral replication, mitigated pathological damage, and induced stronger germinal center and memory B-cell responses, suggesting enhanced B-cell affinity maturation and long-term immune memory. Conclusion:The preF-I53-50 vaccine improves the immunogenicity and protective efficacy of RSV preF through multivalent antigen display.

Objective To explore the therapeutic effect of precise disconnection of pargastric varices guided by endoscopic ultrasound in the treatment of esophagogastric variceal bleeding.Method A retrospective analysis was conducted on 20 patients with cirrhosis esophagogastric variceal bleeding treated with endoscopic ultrasound-guided precise disconnection of pargastric varices from January 1,2024 to December 31,2024.The efficacy was analyzed.Result All 20 patients successfully completed the precise disconnection of pargastric varices under the guidance of endoscopic ultrasound.The injection of tissue gel combined with the placement of spring coils(14 cases)and the injection of tissue gel alone(4 cases)successfully blocked the pargastric varices.All patients did not experience perforation,esophageal and cardia stenosis,massive bleeding,septicemia,or ectopic embolization.One patient who received tissue gel alone had slight bleeding from the pargastric varices after surgery and improved after 3 days of treatment to reduce portal vein pressure.Another one patient who received tissue gel alone had a low-grade fever and normal body temperature after 3 days of anti-infection treatment.Conclusion Precise disconnection of pargastric varices under the guidance of endoscopic ultrasound has a good therapeutic effect on esophagogastric variceal bleeding,with fewer complications such as ectopic embolization,massive bleeding,infection,and perforation.However,close follow-up observation is still needed to address the issue of pargastric varices.

Objective To explore the therapeutic effect of precise disconnection of pargastric varices guided by endoscopic ultrasound in the treatment of esophagogastric variceal bleeding.Method A retrospective analysis was conducted on 20 patients with cirrhosis esophagogastric variceal bleeding treated with endoscopic ultrasound-guided precise disconnection of pargastric varices from January 1,2024 to December 31,2024.The efficacy was analyzed.Result All 20 patients successfully completed the precise disconnection of pargastric varices under the guidance of endoscopic ultrasound.The injection of tissue gel combined with the placement of spring coils(14 cases)and the injection of tissue gel alone(4 cases)successfully blocked the pargastric varices.All patients did not experience perforation,esophageal and cardia stenosis,massive bleeding,septicemia,or ectopic embolization.One patient who received tissue gel alone had slight bleeding from the pargastric varices after surgery and improved after 3 days of treatment to reduce portal vein pressure.Another one patient who received tissue gel alone had a low-grade fever and normal body temperature after 3 days of anti-infection treatment.Conclusion Precise disconnection of pargastric varices under the guidance of endoscopic ultrasound has a good therapeutic effect on esophagogastric variceal bleeding,with fewer complications such as ectopic embolization,massive bleeding,infection,and perforation.However,close follow-up observation is still needed to address the issue of pargastric varices.

Objective:To investigate the efficacy and safety of avatrombopag in promoting hematopoietic reconstitution after allogeneic hematopoietic stem cell transplantation (allo-HSCT).Method:A retrospective analysis was conducted on 60 recipients with hematological malignancies who underwent allo-HSCT at the Affiliated Hospital of Xuzhou Medical University from January 2022 to August 2023. Recipients with hepatic or renal insufficiency before conditioning, those who received other thrombopoietic agents after allo-HSCT, those with severe respiratory or circulatory system diseases, and those with a history of thromboembolic events were excluded. Among them, 30 recipients who received avatrombopag within 14 days post-transplantation were assigned to the avatrombopag group, while the remaining 30 recipients who did not receive any thrombopoietic agents served as the control group. Clinical characteristics, hematopoietic stem cell engraftment, bone marrow proliferation, transfusion requirements, transplant-related complications, and laboratory adverse events were compared between the two groups.Result:The median platelet engraftment time in the avatrombopag group was 13 days (range: 9~25 days), and the neutrophil engraftment time was 13 days (range: 11~21 days). In the control group, he platelet engraftment time was 15 days (range: 10~51 days), and neutrophil engraftment time was 14 days (range: 10~30 days). The difference in platelet engraftment time between the two groups was statistically significant ( P=0.039). Bone marrow analysis on day 28 post-transplant showed that the proportion of recipients with active bone marrow hyperplasia was 96.7% in the avatrombopag group and 73.3% in the control group ( P=0.030); the median number of megakaryocytes was 30 vs. 6, respectively ( P<0.001); and the proportion of mature platelet-producing megakaryocytes was 44% vs. 26.3% ( P<0.001). Regarding transfusion requirements, the median platelet transfusion volume within 28 days post-transplantation was 4.5 U (range: 2~16 U) in the avatrombopag group and 6.5 U (range: 3~32 U) in the control group ( P=0.007). The time to achieve platelet transfusion independence was 13 days (range: 8~25 days) in the avatrombopag group and 14 days (range: 10~36 days) in the control group ( P=0.026). The median red blood cell transfusion volume in both groups was 4 U, with no significant difference ( P=0.354). Medication adherence in the avatrombopag group was 100%. There were no statistically significant differences between the two groups in terms of incidence of post-transplant infections (70% vs. 83.3%), bleeding (50% vs. 60%), graft-versus-host disease (GVHD) (30% vs. 40%), or abnormal laboratory tests (86.7% vs. 90%) (all P>0.05). Conclusion:The use of avatrombopag after allo-HSCT in patients with hematologic malignancies can promote bone marrow hematopoiesis and platelet engraftment, reduce platelet transfusion volume, and shorten the duration of platelet transfusion dependence. Avatrombopag is well tolerated, and no serious adverse reactions were observed during treatment.

Objective:To construct a nanoparticle vaccine displaying the prefusion F (preF) protein of respiratory syncytial virus (RSV) using the I53-50 protein nanoparticle platform, and to systematically evaluate its immunogenicity and protective efficacy.Methods:The RSV preF trimer antigen was genetically fused to I53-50A and assembled in vitro with I53-50B to form preF-I53-50 nanoparticles, theoretically displaying 20 preF antigens per particle. The structure and purity were characterized by size-exclusion chromatography, SDS-PAGE, and negative-stain electron microscopy. BALB/c mice were intramuscularly immunized with varying doses (1 μg or 5 μg) of preF antigen or an equimolar amount of preF-I53-50 nanoparticles. Humoral immunity, B-cell responses, and protective efficacy were assessed following intranasal viral challenge.Results:The preF-I53-50 nanoparticles self-assembled into spherical structures (50-60 nm in diameter) with uniformly arrayed antigens. The nanoparticle vaccine enhanced RSV-specific IgG1 and IgG2a antibody responses, promoting a Th1-biased immune profile. At equimolar preF doses, the neutralizing antibody titers induced by 1 μg and 5 μg nanoparticle formulations were 2.8-fold and 2.3-fold higher, respectively, than those elicited by preF alone ( P<0.05). Notably, even the low-dose nanoparticle group outperformed the high-dose preF group (1.6-fold increase). Viral challenge experiments demonstrated that preF-I53-50 effectively suppressed pulmonary viral replication, mitigated pathological damage, and induced stronger germinal center and memory B-cell responses, suggesting enhanced B-cell affinity maturation and long-term immune memory. Conclusion:The preF-I53-50 vaccine improves the immunogenicity and protective efficacy of RSV preF through multivalent antigen display.

Objective:To investigate the efficacy and safety of avatrombopag in promoting hematopoietic reconstitution after allogeneic hematopoietic stem cell transplantation (allo-HSCT).Method:A retrospective analysis was conducted on 60 recipients with hematological malignancies who underwent allo-HSCT at the Affiliated Hospital of Xuzhou Medical University from January 2022 to August 2023. Recipients with hepatic or renal insufficiency before conditioning, those who received other thrombopoietic agents after allo-HSCT, those with severe respiratory or circulatory system diseases, and those with a history of thromboembolic events were excluded. Among them, 30 recipients who received avatrombopag within 14 days post-transplantation were assigned to the avatrombopag group, while the remaining 30 recipients who did not receive any thrombopoietic agents served as the control group. Clinical characteristics, hematopoietic stem cell engraftment, bone marrow proliferation, transfusion requirements, transplant-related complications, and laboratory adverse events were compared between the two groups.Result:The median platelet engraftment time in the avatrombopag group was 13 days (range: 9~25 days), and the neutrophil engraftment time was 13 days (range: 11~21 days). In the control group, he platelet engraftment time was 15 days (range: 10~51 days), and neutrophil engraftment time was 14 days (range: 10~30 days). The difference in platelet engraftment time between the two groups was statistically significant ( P=0.039). Bone marrow analysis on day 28 post-transplant showed that the proportion of recipients with active bone marrow hyperplasia was 96.7% in the avatrombopag group and 73.3% in the control group ( P=0.030); the median number of megakaryocytes was 30 vs. 6, respectively ( P<0.001); and the proportion of mature platelet-producing megakaryocytes was 44% vs. 26.3% ( P<0.001). Regarding transfusion requirements, the median platelet transfusion volume within 28 days post-transplantation was 4.5 U (range: 2~16 U) in the avatrombopag group and 6.5 U (range: 3~32 U) in the control group ( P=0.007). The time to achieve platelet transfusion independence was 13 days (range: 8~25 days) in the avatrombopag group and 14 days (range: 10~36 days) in the control group ( P=0.026). The median red blood cell transfusion volume in both groups was 4 U, with no significant difference ( P=0.354). Medication adherence in the avatrombopag group was 100%. There were no statistically significant differences between the two groups in terms of incidence of post-transplant infections (70% vs. 83.3%), bleeding (50% vs. 60%), graft-versus-host disease (GVHD) (30% vs. 40%), or abnormal laboratory tests (86.7% vs. 90%) (all P>0.05). Conclusion:The use of avatrombopag after allo-HSCT in patients with hematologic malignancies can promote bone marrow hematopoiesis and platelet engraftment, reduce platelet transfusion volume, and shorten the duration of platelet transfusion dependence. Avatrombopag is well tolerated, and no serious adverse reactions were observed during treatment.

Objective To develop the functions and optimize the automatic monitoring module for arrhythmias of the adverse drug event active surveillance and assessment system-Ⅱ,in order to continuously improve the performance,enhance the monitoring efficiency,and explore the ways to optimize the module.Methods Expand and optimize the functions of the module,increase the customized configuration,and determine the optimal setting conditions;compare the optimized test data with the results of the evaluation studies on the automatic monitoring of drug-induced arrhythmias in large samples of medicated population previously,and verify the optimization extent as well as the accuracy of the module.Results In the new module optimized according to the characteristics of the monitoring population,the function of"mandatory medical order keywords"was added,and it was determined that the inclusion of 6 electrocardiogram examination-related medical order keywords with a frequency of not less than 2 occurrences was the optimal configuration condition for the optimization of the module;combining the results of the previous automatic monitoring and evaluation researches,the system functions were verified and compared under the conditions of using the whole drugs and 2 kinds of single drug.While there was no loss of true positive cases,the number of cases with system alarms decreased by 30.75％,80.13％and 90.82％,respectively,compared with that before the optimization of the module,and the positive predictive value was significantly improved.Conclusion After the function expansion and optimization,the automatic monitoring module of drug-induced arrhythmias significantly reduces the labor cost of case evaluation and keeps the accuracy of monitoring results constant;the new module can better adapt to the demands of different automatic monitoring modes and operates stably,which is more generalizable and flexible,and provides a new way of considering for the research and development of automatic monitoring modules.

Objective To develop a portable collection device of human exhaled breath condensate(EBC)based on natural breathing to meet the needs for rapid screening of human respiratory tract(especially lower respiratory tract)infections.Methods The device consisted of a refrigeration unit,a heat dissipation unit and a condensation unit.The refrigeration unit adopted a TES1-7102 thermoelectric Peltier cooler semiconductor as the refrigeration element;the heat dissipation unit was composed of a high thermal conductivity aluminum heat sink and a high-speed brushless cooling fan;the condensation unit was made up of a cold guide plate and a condenser,in which the cold guide plate was made of thin sheet of aluminum alloy,and the condenser was prepared by 3D printing technology and made of hydrophobic polylactic acid,with primary and secondary 2-stage guide grooves and an ultra-thin condensing surface.The performance of the device was verified in terms of cooling,thermal conductivity,condensation and human EBC collection and content analysis.Results Performance analysis showed that after refrigeration began the temperature difference between the condenser surface and the exhaled gas met the requirements of the condenser,and no obvious thermal resistance was found on the condensing surface so that large droplets could be formed rapidly and then be collected after the gas-liquid phase change of the exhaled gas on the condensing surface.Human EBC collection and content analysis indicated the device realized home self-collection of EBCs from people of all ages,and the concentrations of interleukins,C-reactive protein and other inflammation-related indexes and the pH value of the collected EBC samples were all correlated with respiratory infections in the subjects.Conclusion The device developed with easy operation avoids the discomfort of blowing collection and the risk of saliva contamination,and is worthy promoting for rapid diagnosis and dynamic monitoring of respiratory tract infection and other related diseases.[Chinese Medical Equipment Journal,2024,45(8):32-37]

Objective To investigate the clinical characteristics and prognosis of pneumococcal meningitis(PM),and drug sensitivity of Streptococcus pneumoniae(SP)isolates in Chinese children.Methods A retrospective analysis was conducted on clinical information,laboratory data,and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country.Results Among the 160 children with PM,there were 103 males and 57 females.The age ranged from 15 days to 15 years,with 109 cases(68.1% )aged 3 months to under 3 years.SP strains were isolated from 95 cases(59.4% )in cerebrospinal fluid cultures and from 57 cases(35.6% )in blood cultures.The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87)and 27% (21/78),respectively.Fifty-five cases(34.4% )had one or more risk factors for purulent meningitis,113 cases(70.6% )had one or more extra-cranial infectious foci,and 18 cases(11.3% )had underlying diseases.The most common clinical symptoms were fever(147 cases,91.9% ),followed by lethargy(98 cases,61.3% )and vomiting(61 cases,38.1% ).Sixty-nine cases(43.1% )experienced intracranial complications during hospitalization,with subdural effusion and/or empyema being the most common complication[43 cases(26.9% )],followed by hydrocephalus in 24 cases(15.0% ),brain abscess in 23 cases(14.4% ),and cerebral hemorrhage in 8 cases(5.0% ).Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old,with rates of 91% (39/43)and 83% (20/24),respectively.SP strains exhibited complete sensitivity to vancomycin(100% ,75/75),linezolid(100% ,56/56),and meropenem(100% ,6/6).High sensitivity rates were also observed for levofloxacin(81% ,22/27),moxifloxacin(82% ,14/17),rifampicin(96% ,25/26),and chloramphenicol(91% ,21/23).However,low sensitivity rates were found for penicillin(16% ,11/68)and clindamycin(6% ,1/17),and SP strains were completely resistant to erythromycin(100% ,31/31).The rates of discharge with cure and improvement were 22.5% (36/160)and 66.2% (106/160),respectively,while 18 cases(11.3% )had adverse outcomes.Conclusions Pediatric PM is more common in children aged 3 months to under 3 years.Intracranial complications are more frequently observed in children under 1 year old.Fever is the most common clinical manifestation of PM,and subdural effusion/emphysema and hydrocephalus are the most frequent complications.Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates.Adverse outcomes can be noted in more than 10% of PM cases.SP strains are high sensitivity to vancomycin,linezolid,meropenem,levofloxacin,moxifloxacin,rifampicin,and chloramphenicol.[Chinese Journal of Contemporary Pediatrics,2024,26(2):131-138]

Objective To investigate the correlation between the level of N-terminal pro-Brain natriuretic peptide(NT-proBNP)and cardiorespiratory fitness following acute exposure to high altitude.Methods Forty-six subjects were recruited from the Second Affiliated Hospital of Army Medical University in June 2022,including 19 males and 27 females.After completing cardiopulmonary exercise test(CPET),serological detection of myocardial cell-related markers,and multiple metabolites at a plain altitude(300 meters above sea level),all subjects flew to a high-altitude location(3900 meters above sea level).Biomarker testing and CPET were repeated on the second and third days after arrival at high altitude.Changes in serum biomarker and key CPET indicators before and after rapid ascent to high altitude were compared,and the correlation between serum levels of various myocardial cell-related markers and metabolites and high altitude cardiorespiratory fitness was analyzed.Results Compared with the plain altitude,there was a significant decrease in maximal oxygen uptake after rapid ascent to high altitude[(25.41±6.20)ml/(kg.min)vs.(30.17±5.01)ml/(kg.min),P<0.001].Serum levels of NT-proBNP,Epinephrine(E),plasma renin activity(PRA),angiotensin Ⅱ(Ang Ⅱ),angiotensin-converting enzyme 2(ACE2)and leptin(LEP)significantly increased,with all differences being statistically significant(P<0.05)after acute high altitude exposure.In contrast,no statistically significant differences were observed for creatine kinase MB(CK-MB),cardiac troponin I(cTnI),myoglobin(Myo)and norepinephrine(NE)(P>0.05).Correlation analysis showed a significant negative correlation between NT-proBNP at plain altitude(r=-0.768,P<0.001)and at high altitude(r=-0.791,P<0.001)with maximal oxygen uptake at high altitude.Multivariate linear regression analysis indicated that maximal oxygen uptake at plain altitude(t=2.069,P=0.045),NT-proBNP at plain altitude(t=-2.436,P=0.020)and at high altitude(t=-3.578,P=0.001)were independent influencing factors of cardiorespiratory fitness at high altitude.Conclusion Cardiorespiratory fitness significantly decreases after rapid ascent to high altitude,and the baseline NT-proBNP level at plain altitude is closely related to cardiorespiratory fitness at high altitude,making it a potential predictor indicator for high altitude cardiorespiratory fitness.