Objective To evaluate the effect of low-dose ¹⁸F-fluorodeoxyglucose (FDG) injection on image quality in pediatric patients, calculate the whole-body effective dose and absorbed doses to critical organs, and provide a reference for clinical protection in pediatric low-dose positron emission tomography/computed tomography (PET/CT) examination. Methods A total of 67 pediatric patients aged 4-14 years who underwent ¹⁸F-FDG whole-body PET/CT imaging in the Department of Nuclear Medicine, The First Affiliated Hospital of Shandong First Medical University between January 2024 and December 2025 were enrolled in a retrospective study. According to the injected ¹⁸F-FDG dose, patients were divided into a full-dose group (37 cases, 2.96-3.7 MBq/kg, PET acquisition duration of 10 min) and a low-dose group (30 cases, 1.85-2.4 MBq/kg, PET acquisition duration of 15 min). All scans were performed using a uEXPLORER PET/CT scanner. The standardized uptake value, standard deviation, and signal-to-noise ratio were measured for the liver and mediastinal blood pool. Image quality was compared between the two groups. The PET effective dose was calculated based on body mass index, and the total effective dose was obtained by combining PET effective dose with CT effective dose. The doses to critical organs were calculated according to ICRP Publication 128. Statistical analysis was performed using SPSS 26.0 and Prism 9.0 software. Differences were compared between groups. Results There were no significant differences in age, sex, weight, height, or body mass index between the two groups (P>0.05), while the injected dose showed a significant difference (P<0.001). In terms of image quality, there were no significant differences in standardized uptake value, standard deviation, and signal-to-noise ratio between the two groups. In terms of radiation dose, compared with the full-dose group, the low-dose group showed a 35.13% reduction in PET effective dose and a 15.22% reduction in total effective dose (P<0.05), whereas the CT effective dose was reduced by 2.4% and the difference was not significant (P=0.0892). The doses to critical organs (gonads, breasts, thyroid, red bone marrow, lungs) in the low-dose group were significantly lower than those in the full-dose group (P<0.01). Conclusion Under the premise of meeting clinical diagnostic requirements, low-dose ¹⁸F-FDG whole-body PET/CT imaging in pediatric patients can reduce the overall radiation exposure by 15%, and decrease the doses to critical organs, including the gonads, by more than 20%.

Objective To evaluate the effect of low-dose ¹⁸F-fluorodeoxyglucose (FDG) injection on image quality in pediatric patients, calculate the whole-body effective dose and absorbed doses to critical organs, and provide a reference for clinical protection in pediatric low-dose positron emission tomography/computed tomography (PET/CT) examination. Methods A total of 67 pediatric patients aged 4-14 years who underwent ¹⁸F-FDG whole-body PET/CT imaging in the Department of Nuclear Medicine, The First Affiliated Hospital of Shandong First Medical University between January 2024 and December 2025 were enrolled in a retrospective study. According to the injected ¹⁸F-FDG dose, patients were divided into a full-dose group (37 cases, 2.96-3.7 MBq/kg, PET acquisition duration of 10 min) and a low-dose group (30 cases, 1.85-2.4 MBq/kg, PET acquisition duration of 15 min). All scans were performed using a uEXPLORER PET/CT scanner. The standardized uptake value, standard deviation, and signal-to-noise ratio were measured for the liver and mediastinal blood pool. Image quality was compared between the two groups. The PET effective dose was calculated based on body mass index, and the total effective dose was obtained by combining PET effective dose with CT effective dose. The doses to critical organs were calculated according to ICRP Publication 128. Statistical analysis was performed using SPSS 26.0 and Prism 9.0 software. Differences were compared between groups. Results There were no significant differences in age, sex, weight, height, or body mass index between the two groups (P>0.05), while the injected dose showed a significant difference (P<0.001). In terms of image quality, there were no significant differences in standardized uptake value, standard deviation, and signal-to-noise ratio between the two groups. In terms of radiation dose, compared with the full-dose group, the low-dose group showed a 35.13% reduction in PET effective dose and a 15.22% reduction in total effective dose (P<0.05), whereas the CT effective dose was reduced by 2.4% and the difference was not significant (P=0.0892). The doses to critical organs (gonads, breasts, thyroid, red bone marrow, lungs) in the low-dose group were significantly lower than those in the full-dose group (P<0.01). Conclusion Under the premise of meeting clinical diagnostic requirements, low-dose ¹⁸F-FDG whole-body PET/CT imaging in pediatric patients can reduce the overall radiation exposure by 15%, and decrease the doses to critical organs, including the gonads, by more than 20%.

Objective To evaluate the effect of low-dose ¹⁸F-fluorodeoxyglucose (FDG) injection on image quality in pediatric patients, calculate the whole-body effective dose and absorbed doses to critical organs, and provide a reference for clinical protection in pediatric low-dose positron emission tomography/computed tomography (PET/CT) examination. Methods A total of 67 pediatric patients aged 4-14 years who underwent ¹⁸F-FDG whole-body PET/CT imaging in the Department of Nuclear Medicine, The First Affiliated Hospital of Shandong First Medical University between January 2024 and December 2025 were enrolled in a retrospective study. According to the injected ¹⁸F-FDG dose, patients were divided into a full-dose group (37 cases, 2.96-3.7 MBq/kg, PET acquisition duration of 10 min) and a low-dose group (30 cases, 1.85-2.4 MBq/kg, PET acquisition duration of 15 min). All scans were performed using a uEXPLORER PET/CT scanner. The standardized uptake value, standard deviation, and signal-to-noise ratio were measured for the liver and mediastinal blood pool. Image quality was compared between the two groups. The PET effective dose was calculated based on body mass index, and the total effective dose was obtained by combining PET effective dose with CT effective dose. The doses to critical organs were calculated according to ICRP Publication 128. Statistical analysis was performed using SPSS 26.0 and Prism 9.0 software. Differences were compared between groups. Results There were no significant differences in age, sex, weight, height, or body mass index between the two groups (P>0.05), while the injected dose showed a significant difference (P<0.001). In terms of image quality, there were no significant differences in standardized uptake value, standard deviation, and signal-to-noise ratio between the two groups. In terms of radiation dose, compared with the full-dose group, the low-dose group showed a 35.13% reduction in PET effective dose and a 15.22% reduction in total effective dose (P<0.05), whereas the CT effective dose was reduced by 2.4% and the difference was not significant (P=0.0892). The doses to critical organs (gonads, breasts, thyroid, red bone marrow, lungs) in the low-dose group were significantly lower than those in the full-dose group (P<0.01). Conclusion Under the premise of meeting clinical diagnostic requirements, low-dose ¹⁸F-FDG whole-body PET/CT imaging in pediatric patients can reduce the overall radiation exposure by 15%, and decrease the doses to critical organs, including the gonads, by more than 20%.

BACKGROUND:Allogeneic hematopoietic stem cell transplantation is an important treatment for malignant hematological diseases,and delayed postoperative platelet implantation is a common complication that seriously affects the quality of patient survival;however,there are no standard protocols to improve platelet implantation rates and prevent platelet implantation delays. OBJECTIVE:To compare the safety and efficacy of oral Herombopag Olamine versus subcutaneous recombinant human thrombopoietin for promoting platelet implantation in patients with malignant hematological diseases undergoing haploid hematopoietic stem cell transplantation. METHODS:Clinical data of 163 patients with malignant hematological diseases who underwent haploidentical hematopoietic stem cell transplantation from January 2016 to October 2022 were retrospectively analyzed.A total of 72 patients who started to subcutaneously inject recombinant human thrombopoietin at+2 days were categorized into the recombinant human thrombopoietin group;a total of 27 patients who started to orally take Herombopag Olamine at+2 days were categorized into the Herombopag Olamine group;and 64 patients who did not apply Herombopag Olamine or recombinant human thrombopoietin were categorized into the blank control group.The implantation status,incidence of acute graft-versus-host disease of degree II-IV within 100 days,1-year survival rate,1-year recurrence rate,and safety were analyzed in the three groups. RESULTS AND CONCLUSION:(1)The average follow-up time was 52(12-87)months.The implantation time of neutrophils in the blank control group,recombinant human thrombopoietin group,and Herombopag Olamine group was(12.95±3.88)days,(14.04±3.71)days,and(13.89±2.74)days,respectively,with no statistically significant difference(P=0.352);the implantation time of platelets was(15.16±6.27)days,(17.67±6.52)days,and(17.00±4.75)days,with no statistically significant difference(P=0.287).(2)The complete platelet implantation rate on day 60 was 64.06%,90.28%,and 92.59%,respectively,and the difference was statistically significant(P<0.001).The subgroup analysis showed that the difference between the blank control group and the recombinant human thrombopoietin group was statistically significant(P<0.001),and the difference between the blank control group and the Herombopag Olamine group was statistically significant(P=0.004).The difference was not statistically significant between the recombinant human thrombopoietin group and Herombopag Olamine group(P=0.535).(3)100-day II-IV degree acute graft-versus-host disease incidence in the blank control group,recombinant human thrombopoietin group,and Herombopag Olamine group were 25.00%,30.56%,and 25.93%,respectively,and the difference was not statistically significant(P=0.752).(4)The incidence of cytomegalovirus anemia,cytomegalovirus pneumonia,and hepatic function injury had no statistical difference among the three groups(P>0.05).(5)During the follow-up period,there was no thrombotic event in any of the three groups of patients.(6)The results showed that recombinant human thrombopoietin and Herombopag Olamine could improve the platelet implantation rate of malignant hematological disease patients after haploidentical hematopoietic stem cell transplantation,with comparable efficacy and good safety.

Total-body PET/CT, with its long axial field of view and high sensitivity detector, has shown potential for reducing the dose of radiopharmaceuticals. However, pediatric patients are significantly more sensitive to radiation and have a higher long-term cancer risk than adults, posing fundamental challenges for dose management in PET/CT examinations for these patients. In this article, the technical characteristics of total-body PET/CT and its radiation exposure status in children were systematically analyzed. The radiation exposure could be controlled by the following optimization strategies: adjusting the CT exposure parameters, optimizing the scanning mode, adding reconstruction algorithm, and reducing the injected dose of radioactive tracer. By addressing both external and internal radiation during the PET/CT scanning process, the overall radiation dose received by pediatric patients can be reduced within a certain range. In addition, this article also discusses the technical differences between “total-body” and “whole-body” concepts, and emphasizes that the future optimization of radiation dose in pediatric PET/CT should be realized by integration of personalized scanning protocols. Through reasonable management of scanning protocols and processes, low-dose and high-quality PET/CT imaging can be achieved in clinical environments, thus maximizing protection of pediatric patient health while minimizing the risks associated with ionizing radiation exposure.

Objective To examine the changing prevalence and antimicrobial resistance profiles of Burkholderia cepacia in 52 hospitals across China from 2015 to 2021.Methods A total of 9 261 strains of B.cepacia were collected from 52 hospitals between January 1,2015 and December 31,2021.Antimicrobial susceptibility of the strains was tested using Kirby-Bauer method or automated antimicrobial susceptibility testing systems according to a unified protocol.The results were interpreted according to the breakpoints released in the Clinical & Laboratory Standards Institute(CLSI)guidelines(2023 edition).Results A total of 9 261 strains of B.cepacia were isolated from all age groups,especially elderly patients.The proportion was 11.1％(1 032 strains)in children,significantly lower than the proportion in adults.About half(46.5％,4 310/9 261)of the strains were isolated from patients at least 60 years old and 42.3％(3 919/9 261)of the strains were isolated from young adults.Most isolates(71.1％)were isolated from sputum and respiratory secretions,followed by urine(10.7％)and blood samples(8.1％).B.cepacia isolates were highly susceptible to the five antimicrobial agents recommended in the CLSI M100 document(33rd edition,2023).B.cepacia isolates showed relatively higher resistance rates to meropenem and levofloxacin.However,the resistance rates to ceftazidime,trimethoprim-sulfamethoxazole,and minocycline remained below 8.1％.The percentage of B.cepacia strains resistant to levofloxacin was the highest compared to other antibiotics in any of the three age groups(from 12.4％in the patients＜18 years old to 20.6％in the patients aged 60 years or older).Conclusions B.cepacia is one of the clinically important non-fermenting gram-negative bacteria.Accurate and timely reporting of antimicrobial susceptibility test results and ongoing antimicrobial resistance surveillance are helpful for rational prescription of antimicrobial agents and proper prevention and control of nosocomial infections.

Objective To investigate the distribution and antimicrobial resistance profiles of clinically isolated Haemophilus influenzae and Moraxella catarrhalis in hospitals across China from 2015 to 2021,and provide evidence for rational use of antimicrobial agents.Methods Data of H.influenzae and M.catarrhalis strains isolated from 2015 to 2021 in CHINET program were collected for analysis,and antimicrobial susceptibility testing was performed by disc diffusion method or automated systems according to the uniform protocol of CHINET.The results were interpreted according to the CLSI breakpoints in 2022.Beta-lactamases was detected by using nitrocefin disk.Results From 2015 to 2021,a total of 43 642 strains of Haemophilus species were isolated,accounting for 2.91％of the total clinical isolates and 4.07％of Gram-negative bacteria in CHINET program.Among the 40 437 strains of H.influenzae,66.89％were isolated from children and 33.11％were isolated from adults.More than 90％of the H.influenzae strains were isolated from respiratory tract specimens.The prevalence of β-lactamase was 53.79％in H.influenzae strains.The H.influenzae strains isolated from children showed higher resistance rate than the strains isolated from adults.Overall,779 strains of H.influenzae did not produce β-lactamase but were resistant to ampicillin(BLNAR).Beta-lactamase-producing strains showed significantly higher resistance rates to these antimicrobial agents than the β-lactamase-nonproducing strains.Of the 16 191 M.catarrhalis strains,80.06％were isolated from children and 19.94％isolated from adults.M.catarrhalis strains were mostly susceptible to both amoxicillin-clavulanic acid and cefuroxime,evidenced by resistance rate lower than 2.0％.Conclusions The emergence of antibiotic-resistant H.influenzae due to β-lactamase production poses a challenge for clinical anti-infective treatment.Therefore,it is very important to implement antibiotic resistance surveillance for H.influenzae and guide rational antibiotic use.All local clinical microbiology laboratories should actively improve antibiotic susceptibility testing and strengthen antibiotic resistance surveillance for H.influenzae.

Objective To investigate the changing antibiotic resistance profiles of E.coli isolated from patients in the 52 hospitals participating in the CHINET program from 2015 to 2021.Methods Antimicrobial susceptibility was tested for clinical isolates of E.coli according to the unified protocol of CHINET program.WHONET 5.6 and SPSS 20.0 software were used for data analysis.Results Atotal of 289 760 nonduplicate clinical strains ofE.coli were isolated from 2015 to 2021,mainly from urine samples(44.7±3.2)％.The proportion of E.coli strains isolated from urine samples was higher in females than in males(59.0％vs 29.5％).The proportion of E.coli strains isolated from respiratory tract and cerebrospinal fluid samples was significantly higher in children than in adults(16.7％vs 7.8％,0.8％vs 0.1％,both P＜0.05).The isolates from internal medicine department accounted for the largest proportion(28.9±2.8)％with an increasing trend over years.Overall,the prevalence of ESBLs-producing E.coli and carbapenem resistant E.coli(CREco)was 55.9％and 1.8％,respectively during the 7-year period.The prevalence of ESBLs-producing E.coli was the highest in tertiary hospitals each year from 2015 to 2021 compared to secondary hospitals.The prevalence of CREco was higher in children's hospitals compared to secondary and tertiary hospitals each year from 2015 to 2021.The prevalence of ESBLs-producing E.coli in tertiary hospitals and children's hospitals and the prevalence of CREco in children's hospitals showed a decreasing trend over the 7-year period.The prevalence of CREco in secondary and tertiary hospitals increased slowly.Antibiotic resistance rates changed slowly from 2015 to 2021.Carbapenem drugs(imipenem,meropenem)were the most active drugs amongβ-lactams against E.coli(resistance rate≤2.1％).The resistance rates of E.coli to β-lactam/β-lactam inhibitor combinations(piperacillin-tazobactam,cefoperazone-sulbactam),aminoglycosides(amikacin),nitrofurantoin and fosfomycin(for urinary isolates only)were all less than 10％.The resistance rate of E.coli strains to antibiotics varied with the level of hospitals and the departments where the strains were isolated,especially for cefazolin and ciprofloxacin,to which the resistance rate of E.coli strains from children in non-ICU departments was significantly lower than that of the strains isolated from other departments(P＜0.05).The E.coli isolates from ICU showed higher resistance rate to most antimicrobial agents tested(excluding tigecycline)than the strains isolated from other departments.The E.coli strains isolated from tertiary hospitals showed higher resistance rates to the antimicrobial agents tested(excluding tigecycline,polymyxin B,cefepime and carbapenems)than the strains from secondary hospitals and children's hospitals.Conclusions E.coli is an important pathogen causing clinical infection.More than half of the clinical isolates produced ESBL.The prevalence of CREco is increasing in secondary and tertiary hospitals over the 7-year period even though the overall prevalence is still low.This is an issue of concern.

Objective:To summarize and analyze the clinical characteristics of patients with antibody mediated rejection (AMR) after lung transplantation at China-Japan Friendship Hospital, thereby providing references for clinical management.Methods:A retrospective study was conducted by collecting clinical data of 34 lung transplant recipients (LTRs) diagnosed with AMR between March 2017 and September 2023. The diagnosis of AMR was based on the 2019 International Society for Heart and Lung Transplantation (ISHLT) consensus. Baseline characteristics, primary diseases, pre-diagnostic events, diagnosis, treatment regimens, and outcomes were summarized and analyzed. According to outcomes at the final follow-up (March 31, 2024), patients were divided into survival group (22 cases) and death group (12 cases), and the differences in clinical characteristics and treatments were compared.Results:The incidence of AMR among 551 LTRs was 6.2% (34/551). Among the 34 AMR recipients, 79.4% (27/34) were male, and the median age was 64.0 (54.5, 67.3) years. The primary underlying disease was interstitial lung disease (79.4%). Based on diagnostic classification, 73.5%(25/34) were clinical AMR and 26.5% (9/34) were subclinical AMR. Regarding diagnostic levels, 11.8%(4/34) were proven AMR, 50.0% (17/34) probable AMR, and 38.2%(13/34) possible AMR. Pre-transplant sensitization was detected in 2 patients (5.9%). Post-transplant HLA antibody testing revealed 79.4%(27/34) positive for HLA class Ⅱ antibodies (most commonly DQ7) and 85.3%(29/34) had newly developed HLA antibodies, of which 82.4%(28/34) were de novo donor-specific antibodies (DSA). The most common clinical manifestations were exertional dyspnea(67.6%) and decreased pulse oxygen saturation(47.1%). Chest imaging mainly showed new consolidations or patchy opacities (55.9%), followed by ground-glass opacities (32.4%) and pleural effusion (20.6%). Regarding treatment, 94.1% (32/34) received intravenous immunoglobulin (IVIG), 88.2%(30/34) underwent plasma exchange, and 41.2%(14/34) received intravenous glucocorticoid (IVGC). The most common regimens were "plasma exchange+IVIG" and "IVGC+plasma exchange+IVIG+rituximab", each used in 23.5%(8/34) of cases. The complete HLA antibody clearance rate after treatment was 38.2%. The mortality rates at 3 months, 1 year, and final follow-up after AMR diagnosis were 8.8%, 23.5%, and 35.3%, respectively, with a median survival time of 243.0(96.3, 572.3) days. The survival group had a significantly higher rate of tacrolimus-based triple immunosuppressive therapy (glucocorticoid+tacrolimus+mycophenolate moftil) compared to the death group [86.4% (19/22) vs 50.0% (6/12), P=0.040], while rituximab usage was higher in the death group [75.0% (9/12) vs 13.6% (3/22), P=0.008]. Conclusions:Although AMR after lung transplantation is relatively rare, its diagnosis is challenging, antibody clearance rate after treatment is low, and clinical outcomes are poor, requiring heightened clinical vigilance.

Natural antimicrobial peptides (AMPs) are promising candidates for the development of a new generation of antimicrobials to combat antibiotic-resistant pathogens. They have found extensive applications in the fields of medicine, food, and agriculture. However, efficiently screening AMPs from natural sources poses several challenges, including low efficiency and high antibiotic resistance. This review focuses on the action mechanisms of AMPs, both through membrane and non-membrane routes. We thoroughly examine various highly efficient AMP screening methods, including whole-bacterial adsorption binding, cell membrane chromatography (CMC), phospholipid membrane chromatography binding, membrane-mediated capillary electrophoresis (CE), colorimetric assays, thin layer chromatography (TLC), fluorescence-based screening, genetic sequencing-based analysis, computational mining of AMP databases, and virtual screening methods. Additionally, we discuss potential developmental applications for enhancing the efficiency of AMP discovery. This review provides a comprehensive framework for identifying AMPs within complex natural product systems.