1.Decompression mechanism of symmetrically adduction of lumbar decompression induced resorption of herniated nucleus pulpous
Chunlin ZHANG ; Zhaohua HOU ; Xu YAN ; Yan JIANG ; Su FU ; Yongming NING ; Dongzhe LI ; Chao DONG ; Xiaokang LIU ; Yongkui WANG ; Zhengming CAO ; Tengyue YANG
Chinese Journal of Tissue Engineering Research 2025;29(9):1810-1819
BACKGROUND:Traditional surgery for lumbar disc herniation involves extensive excision of tissue surrounding the nerve for decompression and removal of protruding lumbar intervertebral discs,which poses various risks and complications such as nerve damage causing paralysis,lumbar instability,herniation recurrence,intervertebral space infection,and adjacent vertebral diseases. OBJECTIVE:To propose the symmetrically adduction of lumbar decompression induced resorption of herniated nucleus pulpous technique for lumbar spine symmetrically decompression,showing the induced resorption of herniated nucleus pulpous phenomenon and early clinical efficacy,and then analyze its decompression mechanism. METHODS:214 patients with lumbar disc herniation at Department of Orthopedics,First Affiliated Hospital of Zhengzhou University from March 2021 to May 2023 were enrolled in this study.Among them,81 patients received conservative treatment as the control group,and 133 patients received symmetrically adduction of lumbar decompression induced resorption of herniated nucleus pulpous treatment as the trial group.Before surgery,immediately after surgery(7-14 days),and early after surgery(over 1 year),MRI images were used to measure the volume changes of lumbar disc herniation.CT images were used to measure the posterior displacement distance of the lumbar spinous process ligament complex,as well as the width and height of the lateral recess.Japanese Orthopaedic Association scores were used to evaluate the patient's neurological function recovery. RESULTS AND CONCLUSION:(1)Control group:81 patients with lumbar disc herniation were treated conservatively,with a total of 171 herniated lumbar discs.The average follow-up time was(22.7±23.1)months.The first and second MRI measurements of 171 herniated lumbar discs showed herniated lumbar disc volumes of(551.6±257.9)mm3 and(792.2±330.4)mm3,respectively,with an average volume increase rate of(53.2±44.4)%,showing statistically significant differences(P<0.001).Out of 171 herniated lumbar discs,4 experienced natural shrinkage,with an absorption ratio of 2.3%(4/171)and an absorption rate of(24.5±9.9)%.(2)Trial group:133 patients with lumbar disc herniation had a total of 285 herniated lumbar discs.(1)Immediately after surgery:All patients were followed up immediately after surgery.229 out of 285 herniated lumbar discs experienced retraction,with an absorption ratio of 80.3%(229/285)and an average absorption rate of(21.5±20.9)%,with significant and complete absorption accounting for 6.5%.There were a total of 70 herniated lumbar discs in the upper lumbar spine,with an absorption ratio of 85.7%(60/70),an average absorption rate of(23.1±19.5)%,and a maximum absorption rate of 86.6%.There were 215 herniated lumbar discs in the lower lumbar spine,with an absorption ratio of 78.6%(169/215),an average absorption rate of(21.0±21.3)%,and a maximum absorption rate of 83.2%.Significant and complete absorption of the upper and lower lumbar vertebrae accounted for 5.7%and 6.5%,respectively,with no statistically significant difference(P>0.05).The average distance of posterior displacement of the spinous process ligament complex immediately after surgery was(5.2±2.8)mm.There were no significant differences in the width and height of the left and right lateral recess before and immediately after surgery(P>0.05).The Japanese Orthopaedic Association score immediately after surgery increased from(10.1±3.4)before surgery to(17.0±4.8),and the immediate effective rate after surgery reached 95.6%.(2)Early postoperative period:Among them,46 patients completed the early postoperative follow-up.There were 101 herniated lumbar discs,with an absorption ratio of 94%(95/101)and an average absorption rate of(36.9±23.7)%.Significant and complete absorption accounted for 30.6%,with a maximum absorption rate of 100%.Out of 101 herniated lumbar discs,3 remained unchanged in volume,with a volume invariance rate of 2.97%(3/101).Out of 101 herniated lumbar discs,3 had an increased volume of herniated lumbar discs,with an increase ratio of 2.97%(3/101)and an increase rate of(18.5±18.4)%.The Japanese Orthopaedic Association score increased from preoperative(9.3±5.1)to(23.5±4.0),with an excellent and good rate of 93.4%.(3)The early postoperative lumbar disc herniation absorption ratios of the control group and trial group were 2.3%and 85.9%,respectively,with statistically significant differences(P<0.001).(4)Complications:There were two cases of incision exudation and delayed healing in the trial group.After conservative treatment such as dressing change,no nerve injury or death occurred in the incision healing,and no cases underwent a second surgery.(5)It is concluded that symmetrically adduction of lumbar decompression induced resorption of herniated nucleus pulpous is a new method for treating lumbar disc herniation that can avoid extensive excision of the"ring"nerve and achieve satisfactory early clinical efficacy.It does not damage the lumbar facet joints or alter the basic anatomical structure of the lateral recess,fully preserves the herniated lumbar discs,and can induce significant or even complete induced resorption of herniated nucleus pulpous.Symmetrically adduction of lumbar decompression induced resorption of herniated nucleus pulpous provides a new basis and method for the clinical treatment of lumbar disc herniation.
2.Relationship between screening myopia and physical fitness index in college freshmen without majoring in public safety administration
Chinese Journal of School Health 2025;46(3):431-434
Objective:
To explore the relationship between visual acuity and physical fitness of university freshmen, so as to provide reference for myopia prevention and control for freshmen.
Methods:
From October to November 2022, 2 160 college freshman without majoring in public safety administration, selected from Guangxi Police College in 2022 by using the stratified cluster random sampling method, were reviewed for the results of visual acuity test and physical fitness scores. The physical fitness indices were evaluated by using the Z scores of physical fitness test scores, and the strength of association between the level of physical fitness index and myopia was analyzed by using Logistic regression model.
Results:
Among 2 160 college freshman without majoring in public safety administration, 917 (42.5%) students were diagnosed screening myopia, including 66 (3.1%) cases of high myopia, 383 (17.7%) cases of moderate myopia and 468 (21.7%) cases of mild myopia. The differences in the distribution of visual acuity tests among students with different physical fitness indices, body mass index, and gender were statistically significant ( Z/H=54.50, 49.53, 15.51, P <0.01). Low level and low middle level physical fitness indices were associated with screening myopia among freshmen[ OR (95% CI )=2.81(1.93-4.08),1.87(1.38-2.54)], and low level physical fitness indexes were associated with high myopia [ OR (95% CI )=7.22(2.33-22.32)] ( P <0.01).
Conclusions
Screening myopia among college freshman without majoring in public safety administration is related to physical fitness, and low level and low middle level physical fitness index are risk factors for myopia. Improving the level of physical fitness might be effective in preventing myopia.
3.Development and Application of the Evidence Quality Rating Scale for Ancient Classical Prescriptions in Traditional Chinese Medicine
Juwen ZHANG ; Jianping LIU ; Xiangfei SU ; Wei WEI ; Xiaolan SU ; Xue FENG ; Fanya YU ; Xudong ZHANG ; Junhong YU ; Wei CHEN
Journal of Traditional Chinese Medicine 2025;66(8):804-810
ObjectiveTo develop the Evidence Grading Scale for Ancient classical prescriptions in Traditional Chinese medicine, assess its reliability and validity, and apply it in practice to provide multi-source evidence for clinical practice guidelines development. MethodsLiterature retrieval was conducted to extract and screen existing evaluation dimensions, then the initial items were summarized using thematic analysis. Experts in the clinical medicine, medical history and literature participated in the Delphi questionnaire survey to evaluate and refine the items. An expert consensus meeting was conducted to finalize the included items, refine the method for items evaluation and evidence grading. The evidence quality rating scale for ancient classical traditional Chinese medicine (TCM) prescriptions was then established and tested for reliability and validity. ResultsThrough literature review, extraction, screening and summarization, a total of 3 dimensions and 12 initial items were formed. Questionnaires were sent to 69 experts to evaluate the initial items, with a questionnaire response rate of 100% and an expert authority coefficient of 0.92. All 12 items were retained for they had importance scores above 4. The Evidence Grading Scale on Ancient classical prescriptions in Traditional Chinese medicine includes 3 dimensions with 12 items. The 3 dimensions includes ancient evidence, inheritance status, and modern application. Each dimension contains 4 items, and each item has a full score of 5 points. The evidence was rated as high-level, moderate-level, and low-level according to the final scores. The content validity index (CVI) of the 12 items was >0.9, the average CVI of the scale was 0.98, and the intraclass correlation coefficient (ICC) was 0.90. ConclusionThe Evidence Grading Scale on Ancient classical prescriptions in Traditional Chinese medicine has good reliability and validity, which is practical for use in the development of TCM clinical guidelines and can better support clinical decision-making.
4.The Ferroptosis-inducing Compounds in Triple Negative Breast Cancer
Xin-Die WANG ; Da-Li FENG ; Xiang CUI ; Su ZHOU ; Peng-Fei ZHANG ; Zhi-Qiang GAO ; Li-Li ZOU ; Jun WANG
Progress in Biochemistry and Biophysics 2025;52(4):804-819
Ferroptosis, a programmed cell death modality discovered and defined in the last decade, is primarily induced by iron-dependent lipid peroxidation. At present, it has been found that ferroptosis is involved in various physiological functions such as immune regulation, growth and development, aging, and tumor suppression. Especially its role in tumor biology has attracted extensive attention and research. Breast cancer is one of the most common female tumors, characterized by high heterogeneity and complex genetic background. Triple negative breast cancer (TNBC) is a special type of breast cancer, which lacks conventional breast cancer treatment targets and is prone to drug resistance to existing chemotherapy drugs and has a low cure rate after progression and metastasis. There is an urgent need to find new targets or develop new drugs. With the increase of studies on promoting ferroptosis in breast cancer, it has gradually attracted attention as a treatment strategy for breast cancer. Some studies have found that certain compounds and natural products can act on TNBC, promote their ferroptosis, inhibit cancer cells proliferation, enhance sensitivity to radiotherapy, and improve resistance to chemotherapy drugs. To promote the study of ferroptosis in TNBC, this article summarized and reviewed the compounds and natural products that induce ferroptosis in TNBC and their mechanisms of action. We started with the exploration of the pathways of ferroptosis, with particular attention to the System Xc--cystine-GPX4 pathway and iron metabolism. Then, a series of compounds, including sulfasalazine (SAS), metformin, and statins, were described in terms of how they interact with cells to deplete glutathione (GSH), thereby inhibiting the activity of glutathione peroxidase 4 (GPX4) and preventing the production of lipid peroxidases. The disruption of the cellular defense against oxidative stress ultimately results in the death of TNBC cells. We have also our focus to the realm of natural products, exploring the therapeutic potential of traditional Chinese medicine extracts for TNBC. These herbal extracts exhibit multi-target effects and good safety, and have shown promising capabilities in inducing ferroptosis in TNBC cells. We believe that further exploration and characterization of these natural compounds could lead to the development of a new generation of cancer therapeutics. In addition to traditional chemotherapy, we discussed the role of drug delivery systems in enhancing the efficacy and reducing the toxicity of ferroptosis inducers. Nanoparticles such as exosomes and metal-organic frameworks (MOFs) can improve the solubility and bioavailability of these compounds, thereby expanding their therapeutic potential while minimizing systemic side effects. Although preclinical data on ferroptosis inducers are relatively robust, their translation into clinical practice remains in its early stages. We also emphasize the urgent need for more in-depth and comprehensive research to understand the complex mechanisms of ferroptosis in TNBC. This is crucial for the rational design and development of clinical trials, as well as for leveraging ferroptosis to improve patient outcomes. Hoping the above summarize and review could provide references for the research and development of lead compounds for the treatment for TNBC.
5.Structural and Spatial Analysis of The Recognition Relationship Between Influenza A Virus Neuraminidase Antigenic Epitopes and Antibodies
Zheng ZHU ; Zheng-Shan CHEN ; Guan-Ying ZHANG ; Ting FANG ; Pu FAN ; Lei BI ; Yue CUI ; Ze-Ya LI ; Chun-Yi SU ; Xiang-Yang CHI ; Chang-Ming YU
Progress in Biochemistry and Biophysics 2025;52(4):957-969
ObjectiveThis study leverages structural data from antigen-antibody complexes of the influenza A virus neuraminidase (NA) protein to investigate the spatial recognition relationship between the antigenic epitopes and antibody paratopes. MethodsStructural data on NA protein antigen-antibody complexes were comprehensively collected from the SAbDab database, and processed to obtain the amino acid sequences and spatial distribution information on antigenic epitopes and corresponding antibody paratopes. Statistical analysis was conducted on the antibody sequences, frequency of use of genes, amino acid preferences, and the lengths of complementarity determining regions (CDR). Epitope hotspots for antibody binding were analyzed, and the spatial structural similarity of antibody paratopes was calculated and subjected to clustering, which allowed for a comprehensively exploration of the spatial recognition relationship between antigenic epitopes and antibodies. The specificity of antibodies targeting different antigenic epitope clusters was further validated through bio-layer interferometry (BLI) experiments. ResultsThe collected data revealed that the antigen-antibody complex structure data of influenza A virus NA protein in SAbDab database were mainly from H3N2, H7N9 and H1N1 subtypes. The hotspot regions of antigen epitopes were primarily located around the catalytic active site. The antibodies used for structural analysis were primarily derived from human and murine sources. Among murine antibodies, the most frequently used V-J gene combination was IGHV1-12*01/IGHJ2*01, while for human antibodies, the most common combination was IGHV1-69*01/IGHJ6*01. There were significant differences in the lengths and usage preferences of heavy chain CDR amino acids between antibodies that bind within the catalytic active site and those that bind to regions outside the catalytic active site. The results revealed that structurally similar antibodies could recognize the same epitopes, indicating a specific spatial recognition between antibody and antigen epitopes. Structural overlap in the binding regions was observed for antibodies with similar paratope structures, and the competitive binding of these antibodies to the epitope was confirmed through BLI experiments. ConclusionThe antigen epitopes of NA protein mainly ditributed around the catalytic active site and its surrounding loops. Spatial complementarity and electrostatic interactions play crucial roles in the recognition and binding of antibodies to antigenic epitopes in the catalytic region. There existed a spatial recognition relationship between antigens and antibodies that was independent of the uniqueness of antibody sequences, which means that antibodies with different sequences could potentially form similar local spatial structures and recognize the same epitopes.
6.The effects and mechanisms of silica on alveolar epithelial cell apoptosis
Yali LAN ; Wenyao SU ; Zhiming HU ; Ping WANG ; Bizhu ZHANG ; Na ZHAO
China Occupational Medicine 2025;52(1):10-16
Objective To investigate the effects and mechanisms of silica dust on the apoptosis of alveolar epithelial cell (AEC) through in vitro and animal experiments. Methods i) In vitro experiment. A549 cells were stimulated with 100 mg/L silica suspension for 0, 12, 24 and 48 hours. The cell apoptosis rate was detected by flow cytometry. ii) Animal experiment. Specific pathogen-free male C57BL/6 mice were randomly divided into control, 14-day, 28-day, and 56-day groups, with five mice in each group. The mice in the control group were sacrificed at 56 days after being treated with 40.0 μL 0.9% sodium chloride solution, and the mice in the last three groups were sacrificed at 14, 28 and 56 days after being treated with 40.0 μL silica suspension with a mass concentration of 125 g/L via tracheal exposure method. The lung tissues of mice were collected to measure lung organ coefficients. Masson staining was used to detect the degree of pulmonary fibrosis, and Ashcroft scores were evaluated. The apoptosis of AEC in mice was observed by TUNEL immunofluorescence assay. iii) The mRNA relative expression of apoptosis-related genes in A549 cells and mouse lung tissue was detected using reverse transcription and real-time fluorescence quantitative polymerase chain reaction. Results i) In vitro experiment. The apoptosis rate of A549 cells increased with longer silica exposure (all P<0.05). The relative expression of B cell lymphoma-2 (BCL-2) mRNA in A549 cells in 24 h group and 48 h group decreased (both P<0.05), and the relative expression of BCL-2 associated X protein (BAX) mRNA increased (both P<0.05), compared with 0 h group. The mRNA relative expression of caspase (CASP) -3 and CASP-9 in A549 cells increased with longer silica exposure (all P<0.05). ii) Animal experiment. The lung organ coefficients and Ashcroft score in mice progressively increased (all P<0.05), the degree of pulmonary fibrosis was gradually aggravated, and TUNEL positive cells in lung tissue were gradually increased, while Bax, Casp-3 and Casp-9 mRNA relative expression increased with longer silica exposure (all P<0.05). Conclusion Silica dust may cause pulmonary fibrosis by inducing apoptosis of AEC, with a time-dependent effect. The mechanism may be related to the effect of silica dust on mitochondrial apoptosis through Bcl-2/Bax/Caspase-3 signaling pathway.
7.Effects of Modified Guomin Decoction (加味过敏煎) on Traditional Chinese Medicine Syndromes and Quality of Life in Patients with Mild to Moderate Atopic Dermatitis of Heart Fire and Spleen Deficiency Pattern:A Randomized,Double-Blind,Placebo-Controlled Trial
Jing NIE ; Rui PANG ; Lingjiao QIAN ; Hua SU ; Yuanwen LI ; Xinyuan WANG ; Jingxiao WANG ; Yi YANG ; Yunong WANG ; Yue LI ; Panpan ZHANG
Journal of Traditional Chinese Medicine 2025;66(10):1031-1037
ObjectiveTo observe the clinical efficacy and safety of Modified Guomin Decoction (加味过敏煎, MGD) in patients with mild to moderate atopic dermatitis (AD) of the traditional Chinese medicine (TCM) pattern of heart fire and spleen deficiency, and to explore its possible mechanisms. MethodsIn this randomized, double-blind, placebo-controlled study, 72 patients with mild to moderate AD and the TCM pattern of heart fire and spleen deficiency were randomly divided into a treatment group and a control group, with 36 cases in each group. The treatment group received oral MGD granules combined with topical vitamin E emulsion, while the control group received oral placebo granules combined with topical vitamin E treatment. Both groups were treated twice daily for 4 weeks. Clinical efficacy, TCM syndrome scores, Visual Analogue Scale (VAS) for pruritus, Dermatology Life Quality Index (DLQI) scores, Scoring Atopic Dermatitis (SCORAD) and serum biomarkers, including interleukin-33 (IL-33), interleukin-1β (IL-1β), immunoglobulin E (IgE), and tumor necrosis factor-α (TNF-α) were compared before and after treatment. Safety indexes was also assessed. ResultsThe total clinical effective rates were 77.78% (28/36) in the treatment group and 38.89% (14/36) in the control group, with cure rates of 19.44% (7/36) and 2.78% (1/36), respectively. The treatment group showed significantly better clinical outcomes compared to the control group (P<0.05). The treatment group exhibited significant reductions in total TCM syndrome scores, including erythema, edema, papules, scaling, lichenification, pruritus, irritability, insomnia, abdominal distension, and fatigue scores, as well as reductions in VAS, DLQI, SCORAD, and serum IgE and IL-33 levels (P<0.05 or P<0.01). Compared to the control group, the treatment group had significantly better improvements in all indicators except for insomnia (P<0.05). No adverse events occurred in either group. ConclusionMGD is effective and safe in treating mild to moderate AD patients with heart fire and spleen deficiency pattern. It significantly alleviates pruritus, improves TCM syndromes and quality of life, and enhances clinical efficacy, possibly through modulation of immune responses.
8.Changes of corneal densitometry and higher-order aberrations in high myopia patients after small incision lenticule extraction
Yangjing ZHANG ; Liwei MA ; Guohua CAI ; Su LIU ; Ruifu WANG ; Lipye ZU
International Eye Science 2025;25(6):894-899
AIM: To observe the changes of corneal densitometry(CD)and higher-order aberrations after small incision lenticule extraction(SMILE), and to explore their correlations and influencing factors.METHODS: Prospective study. A total of 62 high-degree myopia and compound myopic astigmatism patients(62 eyes)who underwent SMILE in Urumqi Aier Eye Hospital from December 2022 to November 2023 were collected. The CD, root mean square of corneal higher-order aberrations(RMS HOA), spherical aberration, vertical coma, horizontal coma, and corneal epithelial thickness(CET)of the patients were measured before surgery, and at 1 d, 1 wk, 1, 3, and 6 mo after surgery, respectively.RESULTS:There were 4 patients lost to follow-up during the period, all due to failure to attend scheduled reexaminations. The number of complete and valid cases was 58 eyes. The CD in the central and paracentral regions of the anterior, middle, and total layer of the cornea increased significantly on the first day after surgery(all P<0.003). At 6 mo after surgery, there was a slight but statistically significant decrease in the CD of the central and paracentral regions of the anterior and the total anterior layer(all P<0.003). Compared with the preoperative baseline values, the RMS HOA, spherical aberration, and vertical coma significantly increased at 6 mo after surgery(all P<0.003), while the change in horizontal coma was not statistically significant. Compared with the preoperative baseline values, the CET in the central, paracentral, and peripheral regions of the cornea, as well as the total average CET in the 0-7 mm range of the cornea increased at 6 mo after surgery(all P<0.003). At 1 d after surgery, CD of the anterior layer and total layer in the central region of the cornea were positively correlated with the CET in the central region(rs=0.327, rs=0.250, all P<0.05). At 6 mo after the surgery, the CD of the middle layer and posterior layer in the central corneal region were negatively correlated with the preoperative spherical equivalent and the change of RMS HOA(all P<0.05).CONCLUSION:The anterior CD decreases at 6 mo after SMILE for high myopia correction, and there is a certain correlation between the changes in CD and some clinical parameters.
9.Effect of anterior segment parameters on the rotational stability of Toric intraocular lens
Gengqi* TIAN ; Su* XU ; Yuhang ZHANG ; Yizhuo HU ; Wei SI ; Yifan YANG ; Xintong LI ; Fengyan ZHANG
International Eye Science 2025;25(6):993-998
AIM: To explore the effects of preoperative anterior segment parameters on the rotational stability of Toric intraocular lens(Toric IOL).METHODS:Prospective study. A total of 41 cataract patients(54 eyes)with combined corneal regular astigmatism from March to December 2023 were included and treated with cataract phacoemulsification combined with plate loop Toric IOL implantation in the Department of Ophthalmology of the First Affiliated Hospital of Zhengzhou University. The rotation degree of Toric IOL and uncorrected distance visual acuity(UCDVA)were evaluated at 1 d, 2 wk, and 1 mo postoperatively, the corrected distance visual acuity(CDVA)was evaluated at 2 wk and 1 mo after surgery, and the decentration and tilt of the Toric IOL were assessed at 2 wk postoperatively.RESULTS:A total of 33 patients(40 eyes)were included in this study. The UCDVA(LogMAR)of 1 d, 2 wk and 1 mo postoperatively were 0.10(0.10, 0.30), 0.05(0, 0.10)and 0(0, 0.10), respectively, which was improved compared with the preoperative levels of [0.80(0.49, 1.00)](P<0.001). The CDVA(LogMAR)of 2 wk and 1 mo postoperatively were 0.05(0, 0.15)and 0(0, 0.138), respectively, which was improved compared with preoperative levels of [0.52(0.40, 0.80)](P<0.001). The residual astigmatism of 2 wk and 1 mo postoperatively were 0.625(0.25, 0.75)D and 0.50(0.25, 0.75)D, respectively, which was significantly reduced compared with preoperative astigmatism of [1.82(1.31, 2.59)D](P<0.001). The preoperative anterior segment length(ASL), and lens thickness(LT)were positively correlated with Toric IOL rotation degree at 1 d(rs=0.463, P=0.003; rs=0.340, P=0.032)and 2 wk(rs=0.520, P=0.001; rs=0.409, P=0.009)postoperatively. At 1 mo postoperatively, only ASL was positively correlated with Toric IOL rotation degree(rs=0.463, P=0.003). The results of linear regression analysis showed that preoperative ASL was a predictor of rotation degree at 1 d, 2 wk and 1 mo after surgery(F1 d=10.098, P1 d=0.003; F2 wk=16.915, P2 wk<0.001; F1 mo=10.957, P1 mo=0.002). The rotation degree of Toric IOL was positively correlated with lens decentration(rs=0.360, P=0.043).CONCLUSION:The early postoperative rotation of Toric IOL is positively correlated with ASL, and the rotation is also positively correlated with lens decentration.
10.Simulation analysis of the protective performance of barium sulfate mortar against positron nuclide γ-rays
Zhiqiang XU ; Huaixin NI ; Jiwu GENG ; Lichun LI ; Zaoqin ZHANG ; Shibiao SU ; Meixia WANG ; Ming LIU
Chinese Journal of Radiological Health 2025;34(2):209-213
Objective To obtain the protective performance parameters of barium sulfate mortar against positron nuclide γ-rays, provide reference data for precise shielding calculations, and guide the design, evaluation, and construction of radiation shielding. Methods The FLUKA program was used to build a model for simulating the dose equivalent rate variation around points of interest under the irradiation of the most commonly used positron nuclide 18F with changes in the thicknesses of lead and barium sulfate mortar. The transmission curves of lead and barium sulfate mortar were fitted, and the half-value layer (HVL) and lead equivalence of barium sulfate mortar were calculated based on the fitted curves. Results The ambient dose equivalent rate coefficient of positron nuclide 18F was 1.339 4×10−1 μSv·m2/MBq·h and the HVL for lead was 4.037 mm, with deviations of 0.043% and 1.53% compared to the values provided in the AAPM Report No. 108, respectively. The HVLs for γ-rays produced by 18F, using barium sulfate mortar with apparent densities of 4.20, 4.00, and 3.90 g/cm3 mixed with 35.2-grade cement in a 4∶1 mass ratio, were 2.914, 2.969, and 3.079 cm, respectively. The lead equivalences were


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