Objective To explore the relationship between nutritional status and sarcopenia in patients with chronic kidney disease. Methods This study included 310 patients with chronic kidney disease (assigned to the kidney disease group) and 150 healthy volunteers who underwent physical examinations during the same period (assigned to the healthy group) between May 2022 and October 2024.The clinical data and related nutritional indicators were compared between the two groups, and the correlation between nutritional status indicators and clinical parameters was analyzed. According to the presence or absence of sarcopenia in the kidney disease group, the patients were divided into a sarcopenia group (n=107) and a non-sarcopenia group (n=203). The nutritional indicators were compared between the two subgroups, the correlation between patients' nutritional status and sarcopenia was analyzed, and the value of nutritional status indicators in diagnosing sarcopenia was evaluated. Results BMI, 25(OH)D3, total body water, muscle mass, and adipose mass in the kidney disease group were significantly lower than those in the healthy group (P<0.05), while the UA, SCr, TC, TG, LDL-C, BUN, CRP, and UACR were significantly higher than those in the healthy group (P<0.05). BMI, 25(OH)D3, total body water, and muscle mass in the kidney disease group were significantly negatively correlated with UA, SCr, CRP, TC, TG, and LDL-C (P<0.05), while UACR was significantly positively correlated with UA, SCr, CRP, TC, TG, and LDL-C (P<0.05). BMI, 25(OH)D3, total body water, and total muscle volume in the sarcopenia group were significantly lower than in the non-sarcopenia group (P<0.05), whereas UACR was significantly higher (P<0.05). BMI, 25(OH)D3, total body water, and muscle mass were protective factors against sarcopenia (OR < 1, P < 0.05), whereas UACR was a risk factor associated with sarcopenia (OR > 1, P < 0.05). The AUCs of BMI, 25 (OH) D3, UACR, total body water, and muscle mass for predicting sarcopenia were 0.614, 0.786, 0.881, 0.675, and 0.734, respectively. The combined diagnostic AUC was 0.951, indicating higher diagnostic value. Conclusion In patients with chronic kidney disease, decreases in BMI, 25(OH)D3, total body water, and muscle mass, and an increase in UACR, can all indicate the occurrence of sarcopenia. Among these, BMI, 25(OH)D3, total body water, and muscle mass serve as nutritional status indicators, and their combination with UACR has auxiliary diagnostic value for sarcopenia.

ObjectiveTo explore the association between metabolic score for visceral fat（METS-VF） and cardiometabolic multimorbidity（CMM） as well as cognitive function in the elderly population， revealing the role of METS-VF as an assessment tool in this population， and providing evidence and new perspectives for the early screening and intervention strategies of CMM and cognitive function. MethodsThis study is based on cross-sectional data from the Hubei memory and aging cohort study（HMACS）， which includes elderly individuals aged 60 and above. The METS-VF index was calculated and divided into quartiles（Q1-Q4）. CMM was assessed through a questionnaire， defining CMM as the coexistence of at least two of the following conditions： diabetes， heart disease， and stroke. Standardized cognitive tests were used to evaluate overall cognition， memory， language， executive function， and attention. Logistic and Linear regression analysis was performed to explore the association between METS-VF and the risk of CMM as well as cognitive function. A restricted cubic spline was used to test the dose-response relationship， and subgroup analysis was conducted to assess the variation of METS-VF in different populations. Additionally， multinomial unordered logistic regression was used to evaluate the performance of METS-VF in predicting CMM morbidity patterns. ResultsA total of 3 790 elderly participants aged 60 and above were included. After adjusting for confounding factors， compared with the lowest quartile（Q1）， the Q4 group of METS-VF was associated with a higher risk of CMM ［OR=3.00，95%CI （2.18， 4.16）］， and with lower scores in overall cognition ［b=-0.12， 95%CI （-0.21，-0.04）］， attention ［b=-0.14， 95%CI （-0.24，-0.05）］， and executive function ［b=-0.10， 95%CI （-0.20，-0.00）］. Dose-response analysis did not show a nonlinear relationship between METS-VF and either CMM or cognitive function （P for nonlinear > 0.05）. Subgroup analysis revealed that the male group with higher METS-VF had lower overall cognitive scores， while the female group showed lower executive function scores （P for interaction ＜ 0.05 for both）. Multinomial unordered logistic regression analysis indicated that the METS-VF index was associated with an increased risk of diabetes with coronary heart disease ［OR=2.62，95%CI （1.66， 4.15）］ or concomitant stroke ［OR=2.66，95%CI （1.73， 4.09）］， especially in the group with both diabetes and stroke and coronary heart disease， where the association between METS-VF and the risk was strongest. ConclusionsAn increased METS-VF is associated with a higher risk of CMM and lower scores in overall cognition， attention， and executive function in the elderly population. Diabetes may be a key driving factor in the multimorbidity model. The METS-VF index can serve as a dual-purpose tool for screening cardiovascular metabolic risks and assessing cognitive function.

Objective:To present a set of clinically representative quality assurance (QA) test cases for stereotactic radiosurgery (SRT) plans of multiple intracranial metastases, in order to assess the plan quality and machine execution capabilities.Methods:Based on the clinical characteristics of multiple brain metastases, four groups of test cases with three target volumes (TVs), six TVs, nine TVs, and TVs near organs at risk (OARs) were designed. For these cases, SRT plans were developed, and plan quality was assessed using metrics including the Radiation Therapy Oncology Group conformality index (RTOG CI), gradient index (GI), homogeneity index (HI), and the volume of normal brain tissue receiving a dose of 24 Gy ( V24 Gy), which was defined as the volume enclosed by the 24 Gy isodose line around the Brain-PTV ( V24 Gy of Brain-PTV). Verification plans were generated for each test case, including the verification of point doses, planar doses (PD), and SRS MapCHECK (SMC) semiconductor matrix planar doses. Compared with the calculated result of the treatment planning system (TPS), the criteria for the γ analysis of planar doses were set at 1 mm/2% and 2 mm/2%. Results:For the four groups of test cases, the mean CI, GI, HI, and V24 Gy of Brain-PTV were 1.04±0.03, 3.79±0.40, 0.73±0.01 and (7.46±3.80) cm 3, respectively. The mean deviations of the point doses were 0.88%±0.98%, 1.47%±0.79%, 1.52%± 0.76%, and 1.17% ± 0.38%, respectively. The mean γ passing rates of the single fields for PDs were greater than 98% at 2 mm/2% and exceeding 96% at 1 mm/2%, and the mean γ pass rates of the SMC semiconductor matrix for PDs were 97.75% ± 2.31% and 99.33% ± 0.62%, at 1 mm/2% and 2 mm/2% respectively. Conclusions:The proposed QA test cases for SRT of multiple intracranial metastases allow for the effective assessments of the plan quality and machine execution capabilities and, thus, can assist various centers in clinical applications.

Spectral computed tomography (CT) has triggered a technological revolution in radiodiagnosis while demonstrating its increasing application value in radiotherapy. Employing dual-energy techniques for material decomposition, spectral CT provides optimized solutions for several critical aspects of radiotherapy. Based on a review of the application situation of spectral CT in radiotherapy, this study delved into spectral CT′s significant advantages in image quality improvement, precise dose calculation, and comprehensive quantitative assessment. Furthermore, this study envisioned the development orientations and application prospects of spectral CT.

Objective:Based on HyperArc stereotactic radiotherapy(SRT)technique,six-dimensional free bed combined with double mask fixation was used to treat intracranial tumors,and the positioning errors of within batch and between batches were analyzed,so as to provide basis for the accuracy of clinical treatment of this technique.Methods:A total of 13 patients with intracranial tumors who admitted to Peking Union Medical College Hospital from March to July 2023 were retrospectively selected,and they were treated by using HyperArc SRT technique.The validation images of cone-beam computed tomography(CBCT)of within batch and between batches during treatment were analyzed.The positioning errors of three translational direction[left and right(x),head and foot(y)and abdominal and dorsal(z)]and rotational direction were analyzed.The each positioning error was set as group A,and the remaining error after the positioning error was corrected through six-dimensional free bed was set as group B,and the error post treatment was set as group C.The difference between group B and group C was defined as the change of within batch.According to the margin formula,the positioning error of within batch was used to calculate the required range of margin.Results:Under the mode of six-dimensional free bed correction combined with double mask fixation,a total of 59 times of HyperArc SRT on head were performed.In the comparison of the average errors on the six-dimensional direction among groups A,B and C,the errors of group A on x direction and y direction were respectively(0.119±0.039)and(-0.133±0.047)cm,and the differences of them between group A and group B[(0.004±0.002)and(0.018±0.005)cm]were significant(t=2.890,-3.224,P<0.05).There were no significant differences on other directions between the two groups(P>0.05).The error of RX direction of group B was(0.033±0.021)°,and the difference of that between group B and group C[(0.122±0.045)°]was significant(t=-2.306,P<0.05),while there were no significant differences on other directions(P>0.05).In the margin of the design of the plan of intracranial tumors,the x,y and z directions were respectively 0.6,0.9 and 0.4 mm.Conclusion:In the radiotherapy of using HyperArc SRT technique for intracranial tumors,the use of six-dimensional free bed combined with double mask treatment can significantly shorten the margin,and ensure accurate irradiation for gross tumor volume(GTV)and simultaneously reduce the irradiation volume and dose of surrounding normal tissue.

Objective:An integrated automatic quality control system(automatic quality control instrument)for high dose rate(HDR)afterloader was independently developed.This system was used to measure the placement accuracy,residence time and activity of the radioactive source,so as to assess the accuracy and stability of this system in quality assurance.Methods:The automatic quality control system was connected to the Flexitron type of HDR afterloader through a connecting tube.Quality assurance(QA)plans with different resident positions,clearances,and times were designed for measurement and verification.The measurement length was 1079-1119 mm,and the measurement time was 2-10 s,and the measurement activity was 14,326-28,653 μGy·m2·h-1.The measurements were repeated once per one week in three months,so as to determine the consistency of the measurement parameters in a longer period of time.The measurement results of the placement accuracy,resident time and activity of radioactive source of the HDR 192Ir radioactive source were analyzed.Results:The plate ionization chamber was used to measure the activity of radioactive source.In three months,the measurement deviation of the activity of radioactive source was 1.17%,and the fitted activity decay curve was consistent with the expected decay curve of radioactive source.The measurement accuracies of the positioning of radioactive source were respectively 0.46,0.18,0.23,0.25,and 0.15 mm when the interval step sizes of resident times were respectively 2,3,5,8,and 10 mm,all of them were<1 mm.The measurement accuracy of time was(4.90±0.04)s when the resident time was 5 s.In the measurement accuracy of different resident times(1,2,3,5 and 10s)of same step size,the deviation of them was less than 0.5s.When the resident time was the shortest,the deviation between the read-out value of the automatic system software of quality control and the actually resident time was(0.09±0.04)s.The measurement accuracy gradually stabilized with the increasing of resident times.Conclusion:The automatic quality control instrument can complete the measurements for the positioning accuracy,the accuracy of resident time and the activity of radioactive source,and achieve rapidly and accurately periodic quality assurance.

Objective:To compare the immobilization effect of two different immobilization methods in treatment with CyberKnife for intracranial tumors.Methods:A retrospective analysis was conducted on 48 patients with intracranial tumors who received treatment with CyberKnife in the Department of Radiotherapy at Peking Union Medical College Hospital from June 2023 to July 2024.Based on the different immobilization method,patients were divided into two groups:the Double Shell Positioning System(DSPS)group(n=22)and the Qfix group(n=26).The DSPS group was immobilized using an American full-body integrated positioning frame combined with a carbon fiber bracket and DSPS film,while the Qfix group was immobilized using an Encompass board and Qfix film.All patients were treated with 6 dimensions(6D)-skull tracking technique.During treatment,images were acquired as one times per 60 seconds,which were registered with digitally reconstructed radiograph(DRR)to record and compare the overall relative errors.The data of relative displacement error during treatment was calculated as|dx|=d1-d0,and differences between the two groups were compared.The maximum displacement(|d|=dmax-dmin)was also calculated,and difference in maximum displacement between the two kinds of immobilization methods was analyzed.Results:In the comparison of the overall relative errors between the two kinds of immobilization methods,the median values in the errors of superior-inferior(SI),anterior-posterior(AP),Roll,Pitch,and Yaw directions in the Qfix group were respectively 0.174,0.309,0.150,0.147,and 0.477,which were significantly less than those(0.224,0.316,0.175,0.221,and 0.584)of DSPS group,and the differences were statistically significant(Z=-4.358,-1.698,-2.595,-6.833,-5.371,P<0.05).The difference of the relative displacement errors between two kinds of immobilization methods was not significant(P>0.05),while the median values in all directions were not zero.The comparison of the maximum displacement value between the two kinds of immobilization methods indicated the displacement amounts of Qfix group was less than those of DSPS group on SI,left-right(LR),AP,roll,pitch,and yaw directions,and the differences of them were significant(Z=-3.373,-2.525,-2.488,-3.169,-5.130,-5.166,P<0.05).Conclusion:Both immobilization methods can meet the requirements of clinical treatment.The results of comparison indicate the immobilization effect of Qfix group is best,and the combination of Encompass board and Qfix film is recommended as the immobilization method of CyberKnife-based radiotherapy for intracranial tumors.

Objective:To evaluate the outcomes of minimally invasive therapy for aortic arch pathology after ascending aortic replacement.Methods:A retrospective analysis was conducted at the Department of Cardiovascular Surgery, West China Hospital of Sichuan University from 2016 to 2024. After multidisciplinary discussion, these included patients were evaluated to be at high risk for traditional open surgery. Various minimally invasive repair techniques were employed, including Ⅳb hybrid technique, physician-modified endograft and novel unibody endograft. The study outcomes were technical success, in-hospital and follow-up mortality, stroke, endoleak, and the patency of the supra-aortic vessels.Results:A total of 40 patients(32 males and 8 females) with a median age of 60 years old were included in this study. The technique success rate was 100%, with no deaths or strokes reported. The patency of the supra-aortic vessels was 100%. 10 patients underwent Type Ⅳb hybrid surgery without any endoleaks occurring. Among the 22 patients who received physician-modified endograft, endoleaks were observed in 2 cases. One of these type Ⅰc endoleaks persisted and underwent reintervention. One patient underwent femoral artery replacement due to vascular injury. For the 8 patients who received novel unibody endograft, one case required reintervention due to persistent type Ⅰc endoleaks.Conclusion:With the development of different endovascular techniques and novel branched endograft, patients with aortic arch pathology who are at high risk for redo open surgery can achieve favorable outcomes with various minimal invasive techniques. However, long-term and large-sample follow-up studies are needed for further evaluation.

A novel analytical method was developed in this study by combining online solid phase extraction with ultra performance liquid chromatography-tandem mass spectrometry(Online SPE-UPLC-MS/MS)for simultaneous determination of 50 kinds of steroid hormones in surface water.Specifically,after high-speed centrifugation of 4 mL water samples,the supernatant was directly injected into an Oasis HLB online SPE column for enrichment and purification.Subsequently,the target compounds were transferred to the analytical column via valve switching for separation and analysis.The chromatographic separation was performed on a Thermo Acclaim RSLC C18 column(100 mm×2.1 mm,2.2 μm),using a mobile phase composed of 5 mmol/L ammonium fluoride aqueous solution and acetonitrile.Mass spectrometric detection was conducted in positive ion mode,utilizing multiple reaction monitoring(MRM)with quantification achieved by the internal standard method.The method validation demonstrated that the limits of detection(LOD)for the 50 kinds of steroid hormones ranged from 0.02 to 0.50 ng/L,while the limits of quantification(LOQ)were between 0.08 and 1.67 ng/L.The average recoveries in surface water samples at spiked concentrations of 5,20 and 200 ng/L were between 74.1％and 119％,with relative standard deviations(RSDs)of 0.2％to 9.9％.This method was applied to analyze 11 surface water samples collected from sites surrounding a pharmaceutical and chemical industrial park.A total of 44 kinds of steroid hormones were detected,with concentrations ranging from 0.11 to 88.6 ng/L,revealing the presence of hormone contamination in the environmental waters surrounding industrial areas.Compared with the traditional offline SPE methods,the proposed online SPE technique significantly reduced sample volume requirements and pretreatment time,while minimizing the loss of target compounds during the pretreatment process.Moreover,compared to reported online SPE techniques,this method achieved high-throughput analysis of multiple classes of steroid hormones,with lower detection limits and higher recoveries.Overall,this method provided rapid sample preparation,high sensitivity,and excellent stability,making it suitable for the direct analysis of trace steroid hormones in surface water.

Objective: To evaluate the feasibility of dynamic contrast-enhanced MRI (DCE-MRI) in differentiating tumor deposits (TDs) from metastatic lymph nodes (MLNs) in rectal cancer. Materials and Methods: A retrospective analysis was conducted on 70 patients with rectal cancer, including 168 lesions (70 TDs and 98 MLNs confirmed by histopathology), who underwent pretreatment MRI and subsequent surgery between March 2019 and December 2022. The morphological characteristics of TDs and MLNs, along with quantitative parameters derived from DCE-MRI (K trans , kep, and v e) and DWI (ADCmin, ADCmax, and ADCmean), were analyzed and compared between the two groups.Multivariable binary logistic regression and receiver operating characteristic (ROC) curve analyses were performed to assess the diagnostic performance of significant individual quantitative parameters and combined parameters in distinguishing TDs from MLNs. Results: All morphological features, including size, shape, border, and signal intensity, as well as all DCE-MRI parameters showed significant differences between TDs and MLNs (all P < 0.05). However, ADC values did not demonstrate significant differences (all P > 0.05). Among the single quantitative parameters, v e had the highest diagnostic accuracy, with an area under the ROC curve (AUC) of 0.772 for distinguishing TDs from MLNs. A multivariable logistic regression model incorporating short axis, border, v e, and ADC mean improved diagnostic performance, achieving an AUC of 0.833 (P = 0.027). Conclusion The combination of morphological features, DCE-MRI parameters, and ADC values can effectively aid in the preoperative differentiation of TDs from MLNs in rectal cancer.