OBJECTIVE: To investigate the effects of low-dose irradiated autologous peripheral blood reinfusion (LDIAPBR) on a rat model of radiation-induced leukopenia. METHODS: The rats were randomly divided into four groups. In the LDIAPBR group, LDIAPBR was performed 1 day before modeling (10% of the total circulating blood volume was withdrawn, irradiated with 100 mGy ex vivo, and completely reinfused). Meanwhile, the normal group and model group only underwent blood withdrawal and reinfusion of the same proportion without blood irradiation. Except for the normal group, all groups were subjected to 1 Gy X-ray whole-body irradiation to establish a radiation-induced leukopenia rat model. The positive drug group received subcutaneous injection of rhG-CSF after modeling. It was monitored that the general condition of the rats, peripheral blood cell counts, immune organ indices, bone marrow nucleated cell counts and viability, and the pathological analysis of bone marrow sections was conducted. RESULTS: The LDIAPBR group exhibited significant improvements in overall condition compared to the model group. Notably, compared with the model group, peripheral blood leukocyte and lymphocyte counts were markedly higher in the LDIAPBR group. Furthermore, there was a significant increase in both the number and viability of nucleated cells in the bone marrow. Pathological examination of bone marrow sections revealed increased nucleated cell density and reduced cavity area in the LDIAPBR group. CONCLUSION LDIAPBR can effectively improve hematological parameters and bone marrow hematopoietic function in a rat model of radiation-induced leukopenia, providing a new approach for the prevention and treatment of radiation-related injuries.
Animals ; Leukopenia/prevention & control* ; Rats ; Blood Transfusion, Autologous ; Whole-Body Irradiation ; Radiation Injuries, Experimental/therapy*

Time-of-flight secondary ion mass spectrometer(TOF-SIMS)is a highly sensitive surface analysis instrument with high spatial resolution.Traditional TOF-SIMS instruments for sample targets use high field extraction methods.Although the ion collection efficiency is high,it is prone to issues such as low-energy ion beam defocusing,sample morphology sensitivity,and organic molecule ion dissociation.This study aimed to develope an efficient low-field ion extraction system suitable for TOF-SIMS with a continuous beam source.The SIMION simulation software was used to construct a model of the secondary ion optical extraction system.The key factors affecting the extraction efficiency were studied,and the structural parameters of the extraction cone were optimized.Using an indium target as the sample,an experimental test of the performance of the ion extraction system was carried out on the TOF-SIMS instrument.The influences of the voltages of the ion extraction cone and the single lens on the ion extraction efficiency were consistent with the simulation results.By adopting the technology of deflection and coaxial dynamic compensation,the imaging field of view of the ion extraction system was increased to 500 μm×500 μm.The energy window of the ion extraction system reached 10 eV,and the large imaging depth of field of 400 μm was achieved.In the test of a 5 mg/L cholesterol thin film sample,the signal-to-noise ratio of the characteristic peak[M-OH]+reached 4453.The results showed that this low-field secondary ion extraction system effectively improved the performance of the continuous beam TOF-SIMS instrument.

Guided by the concept of quality by design(QbD), this study optimizes the calcination and quenching process of calcined Magnetitum and establishes the XRD characteristic spectra of calcined Magnetitum, providing a scientific basis for the formulation of quality standards. Based on the processing methods and quality requirements of Magnetitum in the Chinese Pharmacopoeia, the critical process parameters(CPPs) identified were calcination temperature, calcination time, particle size, laying thickness, and the number of vinegar quenching cycles. The critical quality attributes(CQAs) included Fe mass fraction, Fe~(2+) dissolution, and surface color. The weight coefficients were determined by combining Analytic Hierarchy Process(AHP) and the criteria importance though intercrieria correlation(CRITIC) method, and the calcination process was optimized using orthogonal experimentation. Surface color was selected as a CQA, and based on the principle of color value, the surface color of calcined Magnetitum was objectively quantified. The vinegar quenching process was then optimized to determine the best processing conditions. X-ray diffraction(XRD) was used to establish the characteristic spectra of calcined Magnetitum, and methods such as similarity evaluation, cluster analysis, and orthogonal partial least squares-discriminant analysis(OPLS-DA) were used to evaluate the quality of the spectra. The optimized calcined Magnetitum preparation process was found to be calcination at 750 ℃ for 1 h, with a laying thickness of 4 cm, a particle size of 0.4-0.8 cm, and one vinegar quenching cycle(Magnetitum-vinegar ratio 10∶3), which was stable and feasible. The XRD characteristic spectra analysis method, featuring 9 common peaks as fingerprint information, was established. The average correlation coefficient ranged from 0.839 5-0.988 1, and the average angle cosine ranged from 0.914 4 to 0.995 6, indicating good similarity. Cluster analysis results showed that Magnetitum and calcined Magnetitum could be grouped together, with similar compositions. OPLS-DA discriminant analysis identified three key characteristic peaks, with Fe_2O_3 being the distinguishing component between the two. The final optimized processing method is stable and feasible, and the XRD characteristic spectra of calcined Magnetitum was initially established, providing a reference for subsequent quality control and the formulation of quality standards for calcined Magnetitum.
X-Ray Diffraction/methods* ; Drugs, Chinese Herbal/chemistry* ; Quality Control ; Particle Size

The scientific research and innovation capabilities of medical students are intrinsically linked to the sustained and high-quality development of national healthcare initiatives.Cultivating outstanding medi-cal students with independent scientific capabilities and innovative consciousness is a critical component in the education and training of high-level medical professionals.Our investigation revealed that within the imperfections of the cultivating model,some faculty and students at medical schools have an insufficient understanding of scientific research and innovation and lack motivation for engaging in such activities,which hinder the progression of scientific research activities.Consequently,we initiated a teaching practice and exploratory study on the"tutorial system"aimed at fostering medical students'scientific research and innovation abilities.Based on the principle of"research informing teaching,teaching and research advan-cing together,"this study implements a"tutorial system"coordinated by tutors,supplemented by graduate and undergraduate student mentors,to cultivate innovative thinking,stimulate interest in scientific re-search,and enhance practical and research skills among medical students.Through collaborative efforts within"scientific research innovation teams,"various educational methods—including preliminary re-search,in-class and extracurricular activities,intra-group and inter-group interactions,and theoretical and practical applications—are employed to improve and strengthen the cultivation of medical students'scientif-ic research and innovation abilities.This study aims to provide valuable references for optimizing medical education management systems and enhancing the quality of medical student training.

The scientific research and innovation capabilities of medical students are intrinsically linked to the sustained and high-quality development of national healthcare initiatives.Cultivating outstanding medi-cal students with independent scientific capabilities and innovative consciousness is a critical component in the education and training of high-level medical professionals.Our investigation revealed that within the imperfections of the cultivating model,some faculty and students at medical schools have an insufficient understanding of scientific research and innovation and lack motivation for engaging in such activities,which hinder the progression of scientific research activities.Consequently,we initiated a teaching practice and exploratory study on the"tutorial system"aimed at fostering medical students'scientific research and innovation abilities.Based on the principle of"research informing teaching,teaching and research advan-cing together,"this study implements a"tutorial system"coordinated by tutors,supplemented by graduate and undergraduate student mentors,to cultivate innovative thinking,stimulate interest in scientific re-search,and enhance practical and research skills among medical students.Through collaborative efforts within"scientific research innovation teams,"various educational methods—including preliminary re-search,in-class and extracurricular activities,intra-group and inter-group interactions,and theoretical and practical applications—are employed to improve and strengthen the cultivation of medical students'scientif-ic research and innovation abilities.This study aims to provide valuable references for optimizing medical education management systems and enhancing the quality of medical student training.

AIM To study endophytic fungi from Scutellaria baicalensis Georgi.and the enzyme inhibitory activities of their secondary metabolites.METHODS Six different media were used to isolate and purify endophytic fungi from S.baicalensis by tissue homogenate method.The activities of secondary metabolites were evaluated by targeting different enzymes.The highly active strains were identified by molecular biology combined with morphology,and the highly active chemical components were tracked and separated by modern chromatographic separation technology.RESULTS Sixty-four endophytic fungal strains were isolated from S.baicalensis,and one hundred and twenty-eight secondary metabolites were obtained by fermentation.The samples with certain inhibitory activities against adenosine deaminase(ADA),β-lactamase and tyrosinase(TYR)accounted for 14.06%,3.91%and 18.75%,respectively.Strain HTS-23-2 showed high TYR inhibitory activity,and 99%homology with Aspergillus flavus by molecular identification.One compound was isolated from the fermentation samples and identified as kojic acid.CONCLUSION S.baicalensis harbors a rich diversity of endophytic fungi,which serve as a valuable resource for active substances.

Objective:To analyze the clinical characteristics,treatment,and prognosis of adult patients with early T-cell precursor acute lymphoblastic leukemia/lymphoma(ETP-ALL/LBL).Methods:Clinical data of 113 T lymphoblastic leukemia/lymphoma(T-ALL/LBL)patients from January 2006 to January 2019 were collected from three hematology research centers,including Peking University Third Hospital,the First Medical Center of Chinese PLA General Hospital and Institute of Hematology and Blood Diseases Hospital,Chinese Medical University.The clinical characteristics and prognosis of ETP-ALL/LBL patients were analyzed compared with non-ETP-ALL/LBL patients.Results:In 113 T-ALL/LBL patients,13 cases(11.5％)were diagnosed as ETP-ALL/LBL,including 11 males,with a median age of 28(18-53)years.Compared with non-ETP-ALL/LBL patients,there were no significant differences in age,sex,incidence of large mediastinal mass,clinical stage,international prognostic index(IPI)score,white blood cell(WBC)count and lactate dehydrogenase(LDH)level among ETP-ALL/LBL patients.Among 13 ETP-ALL/LBL patients,9 cases(69.2％)achieved complete remission(CR),and there was no statistically significant difference in response rate induced by chemotherapy between ETP-ALL/LBL patients and non-ETP-ALL/LBL patients.Among patients who received chemotherapy without allogeneic hematopoietic stem cell transplantation(allo-HSCT),ETP-ALL/LBL group had a worse 5-year overall survival(OS)rate compared with non-ETP-ALL/LBL group(0 vs 7.1％,P=0.008),while in patients with allo-HSCT,there was no significant difference for 5-year OS rate between the two group(37.5％vs 40.2％,P＞0.05).Multivariate Cox regression analysis showed that CR after induction therapy,allo-HSCT,and LDH level were independent prognostic factors affecting T-ALL/LBL patients.Conclusion:No significant difference in response rate induced by chemotherapy is observed between ETP-ALL/LBL and non-ETP-ALL/LBL patients.Allo-HSCT consolidation after induction of remission therapy may have significant favorable influence on OS for patients with ETP-ALL/LBL.

Objective To investigate the Gram-positive coccus resistance in nationwide's tertiary hospitals and understand the trend of antimicrobial resistance.Methods All the clinical isolates were collected from 19 hospitals and the minimal inhibitory concentrations(MICs)were tested using agar/broth dilution method recommended.Results A total of 1 974 pathogenic Gram-positive coccus from 19 tertiary hospitals in 19 cities nationwide over the period from July 2021 to June 2022 were studied.Based on the MIC results,the prevalence of methicillin resistant Stapylococcus aureus(MRSA)and methicillin resistant Stapylococcus epidermidis(MRSE)were 36.4％and 79.9％respectively.No vancomycin insensitivity Staphylococcus was detected.Staphylococcus aureus were 100％susceptibility to linezolid and teicoplanin.Antibiotic resistance rate of Enterococcus faecalis and Enterococcus faecium to ampicillin were 3.1％and 92.9％.The detectation rate of vancomycin resistant Enterococcus(VRE)was 1.6％.Nonsusceptibility rate of Enterococcus faecalis to linezolid was 32.2％,two consecutive monitoring rises and nonsusceptibility rate of Enterococcus faecium(12.5％)was also significantly increased.The prevalence of penicillin non-susceptible Streptococcus pneumoniae(PNSSP)was 0.8％based on non-meningitis and parenteral administration criterion,decrease of nearly 30 percentage points from the previous surveillance.While for cases of oral penicillin,the rate was 71.8％,showing similar to last time.The results indicated that the number of strains with higher MIC value of penicillin(MIC ≥4 mg·L-1)decreased significantly.There were no significant differences of resistance rates of Stapylococcus aureus,Stapylococcus epidermidis,Enterococcus faecalis,Enterococcus faecium and Streptococcus pneumoniae among various groups such as different department,age,or specimen source.Conclusion VRE detection ratio stablized at a relatively low level.The number of Streptococcus pneumoniae with higher MIC value of penicillin decreased significantly compared with the previous monitoring.The increase of linezolidin-insensitive Enterococcus was noteworthy.

Objective To investigate the Gram-negative bacteria resistance in nationwide's tertiary hospitals and understand the trend of antimicrobial resistance.Method All the clinical isolates were collected from 19 hospitals and the minimal inhibitory concentrations(MICs)were tested using agar/broth dilution method recommended.Results A total of 4 066 pathogenic isolates from 19 tertiary hospitals in 19 cities nationwide over the period from July 2021 to June 2022 were studied.Based on the MIC results,Escherichia coli and Klebsiella pneumoniae showed extended spectrum β-lactamase(ESBLs)phenotype rates of 55.0％and 21.0％,respectively,ESBLs phenotype rate of Klebsiella pneumoniae keep going down.The ratios of carbapenems resistance Klebsiella pneumoniae increased by 5 percentage points compared with the previous monitoring.Carbapenems,moxalactam,sitafloxacin,β-lactam combination agents,fosfomycin trometamol,and amikacin displayed desirable antibacterial activity against Enterbacterales,susceptibal rates were above 75％.In addition,tigacycline,omacycline,colistin and fluoxefin maintained good antibacterial activity against their respective effective bacteria/species,and the bacterial sensitivity rates by more than 80％.Resistance rates of Pseudomonas aeruginosa and Acinetobacter baumannnii to imipenem were 26.3％and 72.1％and multidrug-resistant(MDR)detection rates were 41.1％and 77.3％,extensively drug-resistant(XDR)were 12.0％and 71.8％,respectively.Comparison of drug resistance rates from different wards,ages and specimen sources indicated that the proportion of resistance in Klebsiella pneumoniae and Acinetobacter baumannii isolated from intensive care unit(ICU)were significantly higher than non-ICU.Carbapenem resistance rates of Klebsiella pneumoniae isolated from ICU were more than 35％.Resistance rates of Haemophilus influenzae isolated in children to β-lactam,macrolide,clindamycin and ESBLs detection rate in Klebsiella pneumoniae isolated from children were more than those from adults and the old people,so bacterial resistance in children is an important problem in China.Conclusion ESBLs detection rate of Escherichia coli increased slightly after years of continuous decline.The proportion of carbapenem resistant Pseudomonas aeruginosa was stable,but the resistance rate of Klebsiella pneumoniae and Acinetobacter baumannii to carbapenems was still increased,which should be paid more attention.

italic>Fusarium oxysporum widely exists in farmland soil and is one of the main pathogenic fungi of root rot, which seriously affects the growth and development of plants and often causes serious losses of cash crops. In order to screen out natural compounds that inhibit the activity of Fusarium oxysporum more economically and efficiently, random forest, support vector machine and artificial neural network based on machine learning algorithms were constructed using the information of known inhibitory compounds in ChEMBL database in this study. And the antibacterial activity of the screened drugs was verified thereafter. The results showed that the prediction accuracy of the three models reached 77.58%, 83.03% and 81.21%, respectively. Based on the inhibition experiment, the best inhibition effect (MIC = 0.312 5 mg·mL^-1) of ononin was verified. The virtual screening method proposed in this study provides ideas for the development and creation of new pesticides derived from natural products, and the screened ononin is expected to be a potential lead compound for the development of novel inhibitors of Fusarium oxysporum.