Objective To measure radiation filed distribution in the treatment room of the Varian Halcyon medical linear accelerator, and to provide a basis for shielding design and potential exposure analysis of treatment rooms for this type of accelerator. Methods Under the 6 MV X-ray (FFF) mode at a maximum dose rate of 800 MU/min and a maximum irradiation field of 28.00 cm × 28.00 cm, a total of 540 MU was delivered during gantry rotation. Radiation field distribution was measured using thermoluminescence dosimeters located at multiple points in the room. The measured data were then applied to shielding calculations, and the results were compared with those obtained using empirical formulas. Results The overall radiation levels in the treatment room were in the range of 12.2 µGy/540 MU to 5.520 Gy/540 MU, with the highest dose (5.520 Gy/540 MU) observed at the isocenter, and the lowest dose (12.2 µGy/540 MU) recorded at approximately 6.5 m from the gantry head. The radiation levels at most points were within the range of 100-1000 µGy/540 MU. At heights of 0.5, 1.1, and 1.7 m, the radiation field exhibited a rapid attenuation from the beam center outward, with a faster decay along the treatment couch direction (Y-axis) than along the perpendicular direction (X-axis). Shielding calculations based on the measured radiation field yielded required wall thicknesses of 1219 mm (east wall), 949 mm (south wall), 1235 mm (west wall), and 1252 mm (north wall), all of which were smaller than those calculated using empirical formulas. Conclusion Thermoluminescence dosimeter is suitable for multi-point in situ measurement of radiation field distribution in Halcyon accelerator treatment rooms. The measurement results can be used to optimize the shielding design of Halcyon accelerator treatment rooms.

Objective To investigate the incidence and severity of symptoms in patients with gastric cancer who received chemotherapy,we constructed a symptom network to explore core symptoms and bridge symptoms.Furthermore,the study explores the association between core symptoms and Traditional Chinese Medicine(TCM)constitutions.Methods Patients with gastric cancer who received chemotherapy in the medical oncology and surgical oncology department from March to August 2023 were selected for the study using a convenience sampling method.The MD Anderson Symptom Inventory Gastrointestinal Cancer was used for evaluating gastrointestinal symptoms and their severity among patients receiving chemotherapy for gastric cancer,as well as assessing the classification of TCM constitution among patients.The symptom network model was constructed using the R programming language,and the central index was analyzed to determine the core symptoms and bridge symptoms.Binary logistic regression analysis was employed to assess the association between different physical conditions and the occurrence of core symptoms.Results A total of 346 electronic questionnaires were collected,with 340 valid ones,and the effective recovery rate was 98.3％.The 3 most prevalent and severe symptoms among the 340 patients with gastric cancer were fatigue(85.59％),lack of appetite(82.35％),and taste alteration(81.18％).The centrality index results indicated that grief exhibited the highest intensity,medium,and compactness centrality values(rs=8.23,rb=2.00,rc=0.03),making it the core symptom of this condition.Sleep disorders,lack of appetite,drowsiness,and taste alteration were identified as bridging symptoms with bridge intensities of 0.74,0.76,0.99,and 0.94 respectively.The results of Spearman correlation analysis showed that there was a positive correlation between sadness and qi-deficiency constitution,phlegm-dampness constitution(P＜0.05).The phlegm-dampness constitution was positively correlated with the taste alterations(P＜0.05).Conclusion In patients with gastric cancer,fatigue emerges as the most prominent symptom,while sadness assumes the core symptom.Additionally,sleep disorder,lack of appetite,drowsiness,and taste alteration are bridge symptoms.According to the principles of TCM constitution,qi-deficiency and phlegm-dampness are constitutions associated with a higher risk of experiencing sadness,and phlegm-dampness is a constitution associated with a higher risk of taste changes.Nurses can integrate core symptoms and TCM constitutions characteristics to optimize the strategies for symptom intervention.

Objective To explore the potential influencing factors and complex pathways affecting rehabilitation effect for children with autism spectrum disorder(ASD)from the perspective of parental efficacy in doctor-patient communication,and to provide evidence for improving the quality of rehabilitation service for children with ASD. Methods An anonymous face-to-face questionnaire survey was conducted to collect general demographic information of parents of children with ASD at designated rehabilitation institutions in Gansu province.The data included paren-tal efficacy in doctor-patient communication,parental compliance of treatment and children's rehabilitation out-comes were collected.A structural equation model was used to explore the impact mechanism of parental commu-nication efficacy on the rehabilitation outcomes of children with ASD. Results Data from 519 parents at 37 rehabilitation institutions across 13 cities/counties in Gansu province were collect-ed.Significant positive correlations were found between parental efficacy in doctor-patient communication,doc-tor-patient relationships,parental compliance with treatment and rehabilitation outcomes for children with ASD(P＜0.05).Through structural equation model analysis,the standardized direct effect of children with ASD from parents'doctor-patient communication efficacy was 0.151(P=0.023).The mediating effect of doctor-patient rela-tionship and parental compliance with treatment were 0.160(P=0.001)and 0.111(P=0.001),respectively,with a chained mediating effect of 0.035(P=0.001).The pathway"parental efficacy in doctor-patient communica-tion → doctor-patient relationship → ASD child's rehabilitation outcome"accounted for the highest proportion of the total mediating effect,at 52.29%. Conclusion Parental doctor-patient communication efficacy may positively impact on the rehabilitation outcomes of chil-dren with ASD directly,and indirectly through the doctor-patient relationship and parental compliance with treat-ment.Rehabilitation institutions should focus on fostering parental communication skills and enhancing high-quality and humanized rehabilitation services.

Objective:To explore the diagnosis and treatment of adolescence-onset methylenetetrahydrofolate reductase (MTHFR) deficiency.Methods:This was a retrospective case study. Nine patients with adolescence-onset MTHFR deficiency were diagnosed at Peking University First Hospital from January 2016 to December 2022, and followed up for more than 1 year. Their general information, clinical manifestations, laboratory tests, cranial images, MTHFR gene variants, diagnosis, treatment, and outcome were analyzed retrospectively.Results:The 9 patients came from 8 families. They had symptoms at age of 8.0 years to 17.0 years and diagnosed at 9.0 years to 17.5 years. Eight were male and 1 was female. Two patients were brothers, the elder brother developed abnormal gait at 17.0 years; and the younger brother was then diagnosed at 15.0 years of age and treated at the asymptomatic stage, who was 18.0 years old with normal condition during this study. The main manifestations of the 8 symptomatic patients included progressive dyskinesia and spastic paralysis of the lower limbs, with or without intellectual decline, cognitive impairment and behavioral abnormalities. Totally, 15 variants of MTHFR gene were identified in the 9 patients, including 8 novel variants. Five patients had brain image abnormalities. Increased plasma total homocysteine level (65-221 μmol/L) was found in all patients, and decreased to 20-70 μmol/L after treatment with betaine and calcium folinate. Besides, the 8 symptomatic patients had their behavior and cognitive problems significantly improved, with a legacy of lower limb motor disorders.Conclusions:Late-onset MTHFR deficiency can occur in adolescence. The diagnosis is usually delayed because of non-specific clinical symptoms. The test of blood total homocysteine could be used as a selective screening test. Eight novel varients of MTHFR gene were identified. Timely treatment can improve clinical condition significantly, and pre-symptomatic treatment may prevent brain damage.

Objective:To observe the effects of problem-based learning (PBL) and case-based learning (CBL) combined with self-media platform in clinical probation teaching of gastroenterology.Methods:From July 2019 to June 2020, 60 students in the Department of Gastroenterology of the Army Characteristic Medical Center of PLA were assigned to the traditional teaching group (control group, n=30) and the PBL and CBL combined with the self-media platform teaching group (experimental group, n=30). After the teaching, theoretical examination, practical assessment, and questionnaires were used to evaluate the effects of the two teaching methods. SPSS 23.0 was used to perform the t-test. Results:The comprehensive scores of students in the experimental group, including theoretical examination score (86.60±1.17) and practical assessment score (86.40±0.83), were significantly higher than those in the control group [(81.70±0.98), (82.00±1.18), P<0.001]. The questionnaire survey showed that the experimental group was superior to the traditional teaching group in terms of self-study and data access ability, students' self-confidence, and satisfaction with teaching ( P<0.001). Conclusion:PBL and CBL combined with self-media platform uses actual medical records to guide students to discuss, analyze, and summarize clinical issues. Combined with flexible learning on the self-media platform, this method breaks through the limitations of traditional teaching models and improves teaching quality and learning satisfaction. Therefore, this method can be promoted in clinical probation teaching of gastroenterology.

Aerosol microorganisms are important constituents of aerosols. They participate in physical and chemical reactions in the air and are also closely related to disease transmission and human health. With the SARS-CoV-2 pandemic， aerosol microorganisms have become a public health topic of great concern. Studying the composition and influencing factors of the air microbiome therefore has significant public health implications. Due to the limitations of traditional technologies for sampling and determination， the aerosol microbiome has not been fully understood. However， with the development and maturity of high-throughput sequencing technology， the aerosol microbiome has shown promising research prospects. This article reviews the composition， characteristics， detection methods and influencing factors of aerosol microorganisms， providing basic knowledge for further research on the air microbiome. In-depth research on microbial aerosols has significant implications on urban air quality control， national security and public health.

ObjectiveTo establish a quantitative analysis multi-components by single marker method （QAMS） for five main components （aucubin， geniposidic acid， chlorogenic acid， asperuloside and rutin） in Eucommiae Folium， to verify its feasibility and applicability in the determination of Eucommiae Folium， so as to provide a scientific basis for the development of quality standard of this herb. MethodHigh performance liquid chromatography was performed on a Welch Boltmatetm™ C₁₈ column （4.6 mm×100 mm， 2.7 μm） with methanol （A）-0.2% phosphoric acid aqueous solution （B） as the mobile phase for gradient elution （0-8 min， 3%A； 8-10 min， 3%-11%A； 10-26 min， 11%A； 26-27 min， 11%-25%A； 27-60 min， 25%-32%A）， the column temperature was set at 30 ℃， the flow rate was 0.6 mL·min^-1， the detection wavelengths were at 210 nm and 254 nm. Chlorogenic acid was used as an internal reference to establish the relative correction factors （f） between it and the other four components， and the contents of the five components in 14 batches of Eucommiae Folium were determined by QAMS and external standard method （ESM）， respectively. ResultThe f values of chlorogenic acid to aucubin， geniposidic acid， asperuloside and rutin were 3.13， 1.45， 2.64 and 0.56， respectively. Repeatability was good under different experimental conditions， relative standard deviation （RSD） was <5.0%. The contents of aucubin， geniposidic acid， chlorogenic acid， asperuloside and rutin in 14 batches of Eucommiae Folium were 1.340-28.975， 0.252-36.086， 10.016-27.443， 1.396-8.646， 0.533-1.766 mg·g^-1， respectively. There were no significant difference between content results of QAMS and that of ESM （RSD<5.0%）. ConclusionQAMS established with chlorogenic acid as the internal reference can be used to determine the contents of five components in Eucommiae Folium， and this method is simple and accurate. After comprehensive evaluation， the quality standard of Eucommiae Folium in subsequent editions of Chinese Pharmacopoeia is suggested that three main active components， chlorogenic acid， aucubin and geniposidic acid， are selected as quality markers， and their content limits are recommended not less than 1.5%， 1.0% and 1.0%， respectively. This quality standard draft can avoid the potential quality risk due to poor specificity and low content limit of the index component （chlorogenic acid） in the previous editions of Chinese Pharmacopoeia.

Objective:To investigate the factors affecting phenotypes in the patients of methylmalonic acidemia combined with homocysteinemia cblC type with MMACHC c. 609G>A homologous variant. Methods:A retrospective study on the clinical manifestations, complications, treatment, and outcome in 164patients of cblC type with MMACHC c. 609G>A homologous variant was conducted.The patients were diagnosed by biochemical and genetic analysisfrom January 1998 to December 2020. Results:Among the 164 patients, 2 cases were prenatally diagnosed and began treatment after birth. They are 3 and 12 years old with normal physical and mental development. Twenty-one cases were diagnosed by newborn screening. Among them, 15 cases had with normal development. They were treated fromthe age of two weeks at the asymptomatic period. Six cases began treatment aged 1 to 3 months after onset. Their development was delayed. One hundred and forty-one cases were clinically diagnosed. Their onset age ranges from a few minutes after birth to 6 years old. 110 cases had early-onset (78.0%). 31 cases had late-onset (22.0%). Five of them died. 24 patients lost to follow-up. Of the 141 clinically diagnosed patients, 130 (92.2%) with psychomotor retardation, 69 (48.9%) with epilepsy, 39 (27.7%) with anemia, 30 (21.3%) had visual impairment, 27 (19.1%) had hydrocephalus, 26 (18.4%) had feeding difficulties, 7 (5.0%) with liver damage, and 5 (3.5%) with metabolic syndrome. The frequency of hydrocephalus and seizures was significantly higher in the early-onset group. The urinary methylmalonic acid increased significantly in the patients with epilepsy. During the long-term follow-up, the level of plasma total homocysteine in the seizure-uncontrolled group was significantly higher than that in the seizure-controlled group, the difference had a statistical significance ( P<0.05). Conclusion:Most of the patients with MMACHC c. 609G>A homozygous variant had early-onset disease, with a high mortality and disability rate. If not treated in time, it will lead to neurological damage, resulting in epilepsy, mental retardation, hydrocephalus, and multiple organ damage. Pre-symptomatic diagnosis and treatment are crucial to prevent irreversible neurological damage. Neonatal screening and prenatal diagnosis are important to improve the outcome of the patients.

Objective:To investigate the relationship between the changes of immune indexes and prognosis in patients with sepsis.Methods:Based on the hospitalization information from 2008 to 2019 in the American Medical Information Mart for Intensive Care-Ⅳ v2.0 (MIMIC-Ⅳ v2.0), the hospitalized data including CD3 count, CD4 count, CD8 count, CD4/CD8 ratio, immunoglobulins (IgA, IgG, IgM) levels and lymphocyte counts, gender, age, body mass index (BMI), sequential organ failure assessment (SOFA), and prognosis of patients with coronary heart disease, hypertension, diabetes mellitus, underlying diseases, and 28-day prognosis were collected. The immunological indexes affecting the prognosis of patients with sepsis were compared and analyzed. The receiver operator characteristic curve (ROC curve) was drawn to analyze the value of immunological indexes in predicting the 28-day prognosis of patients with sepsis.Results:A total of 33 745 patients were enrolled in the study, including 1 509 cases of sepsis and 32 236 cases without sepsis. Among the patients with sepsis, there were 1 084 cases alive and 425 cases died within 28 days. BMI (kg/m 2: 33.25±28.71 vs. 28.90±15.28) and IgA levels within 3 days and 7 days after admission in sepsis group were significantly higher than those in the non-sepsis group [within 3 days after admission: (275.01±216.96) mg/L vs. (85.99±75.76) mg/L; within 7 days after admission: (275.01±216.96) mg/L vs. (85.99±75.76) mg/L, all P < 0.05]. CD3 count, CD8 count within 3 days and 7 days after admission in sepsis group were significantly lower than that in the non-sepsis group [within 3 days after admission: CD3 counts were (1 080.74±849.23)/μL vs. (1 242.91±889.24)/μL, CD8 counts were (558.07±368.77)/μL vs. (625.07±529.66)/μL; within 7 days after admission: CD3 counts were (1 079.69±850.61)/μL vs. (1 242.48±889.23)/μL, CD8 counts were (556.70±467.23)/μL vs. (624.93±429.78)/μL, all P < 0.05]. The proportion of patients with hypertension, diabetes and coronary heart disease were significantly higher than those in the non-sepsis group [hypertension: 10.07% (152/1 509) vs. 2.47% (796/32 236), diabetes: 50.10% (756/1 509) vs.15.18% (4 895/32 236), coronary heart disease: 31.21% (471/1 509) vs. 19.19% (6 186/32 236), all P < 0.05]. In the sepsis group, the CD3 count, CD4 count and CD4/CD8 ratio in the survival group were significantly higher than those in the death group within 3 days and 7 days after admission [within 3 days after admission: CD3 counts were (1 127.20±857.14)/μL vs. (938.26±810.50)/μL, CD4 counts were (559.76±507.18)/μL vs. (338.75±267.11)/μL, CD4/CD8 ratios were 1.87±0.80 vs. 1.02±0.12; within 7 days after admission: CD3 count were (1 124.01±810.53)/μL vs. (943.78±808.21)/μL, CD4 count were (559.56±507.36)/μL vs. (341.95±266.56)/μL, CD4/CD8 ratios were 1.88±0.79 vs. 1.03±0.13, all P < 0.05]. The area under the ROC curve (AUC) of CD4/CD8 ratio within 3 days after admission in predicting the prognosis of septic patients at 28 days was 0.615 [95% confidence interval (95% CI) was 0.555-0.671], the sensitivity was 70.83%, and the specificity was 52.49%. Conclusions:Hypertension, coronary heart disease and diabetes are more likely to induce sepsis. The changes of immune indexes in patients with sepsis will occur in the early stage. Early CD4/CD8 index can predict the prognosis of patients with sepsis to a certain extent.

Objective:To explore the causes and influencing factors of financial toxicity in young breast cancer survivors, and to provide evidence for intervention program development to improve financial toxicity in young breast cancer survivors.Methods:Using descriptive qualitative research methods, 29 young breast cancer patients from September to December 2021 in Breast Surgery Follow-up Clinic of Fudan University Shanghai Cancer Center were interviewed. The Nvivo 12.0 qualitative data analysis software was used to analyze the data.Results:Four themes were extracted as following, direct cost of cancer treatment was the primary cause of financial toxicity, indirect costs related to cancer and treatment cannot be ignored, long-term effects of cancer and treatment further exacerbated financial toxicity, and cancer-related financial toxicity was also influenced by a variety of other factors.Conclusions:Multiple causes affected the experience of financial toxicity in young breast cancer survivors. The occurrence and risks of financial toxicity in young breast cancer survivors should be assessed. Intervention and support should be provided to meet the needs of young breast cancer survivors.