Evaluation of Monochromatic Excitation X-ray Fluorescence Spectrometry for Rapid Thallium Detection in Biological Samples Using Animal Models

Monochromatic excitation X-ray fluorescence (ME-XRF) spectrometry is a novel technique for trace element analysis, characterized by its simplicity, rapidity, and low cost. The objective of this study was to evaluate the applicability of ME-XRF technique for the measurement of thallium in biological samples. Acute and subacute thallium poisoning experiments were conducted to simulate various scenarios, with blood, urine, and 10 distinct organs collected. Detection was initially performed using ME-XRF technique, followed by validation with inductively coupled plasma mass spectrometry (ICP-MS). Excellent agreement between ME-XRF and ICP-MS values was demonstrated by means of paired sample t-tests and intraclass correlation coefficients. Subsequently, the practical implementation of the proposed technique was demonstrated through an actual case study. In conclusion, this study validates ME-XRF as a suitable alternative to ICP-MS for the measurement of trace heavy metals in biological samples. These efforts promote the development of simpler and faster techniques for heavy metal detection, thereby presenting novel avenues for the prevention and diagnosis of heavy metal poisoning.

Rapid determination of glyphosate and glufosinate in human blood by probe electrospray ionization tandem mass spectrometry

In forensic science, glyphosate (GLYP) and glufosinate (GLUF), a class of non-selective broad-spectrum herbicides, have been frequently encountered in many fatal poisoning and suicide cases due to their widespread availability. Therefore, it is essential to develop an effective method for detecting these compounds. Some conventional methods, such as gas chromatography-mass spectrometry (GC-MS) or liquid chromatography-mass spectrometry (LC-MS), have been reported to detect these compounds. However, these methods are not ideal for their time-consuming and non-sensitive feature. Herein, probe electrospray ionization (PESI) tandem mass spectrometry (MS/MS), a fast and sensitive technique, was applied for the determination of GLYP and GLUF in human blood, which can obtain analytical results within 0.5 min without derivatization and chromatographic separation. After protein precipitation of blood samples, the supernatant was mixed with isopropanol and ultra-pure water (1:1 v/v). Then, 8 μL of the mixture was introduced into the plastic sample plate for PESI-MS/MS analysis. The limits of detection (LODs) of the method were 0.50 μg/mL and 0.25 μg/mL for two analytes, and the limits of quantitation (LOQs) were both 1.00 μg/mL, which are higher than the concentration of reported poisoning and fatal cases. In the linear range of 1-500 μg/mL, the regression coefficients (r2) for GLYP and GLUF were over 0.99. The matrix effects ranged from 94.8 % to 119.5 %, and the biases were below 4.3 %. The recoveries ranged between 84.8 % and 107.4 %, and the biases were below 7.6 %. Meanwhile, the method was effectively utilized to detect and quantify the blood, urine, and other samples. Consequently, the results suggest that PESI-MS/MS is a straightforward, fast, and sensitive method for detecting GLUF and GLYP in forensics. In the future, PESI-MS/MS will become an indispensable technique for polar substances in grassroots units of public security where rapid detection is essential.

[Preliminary study on automatic quantification and grading of leopard spots fundus based on deep learning technology]

Objective: To achieve automatic segmentation, quantification, and grading of different regions of leopard spots fundus (FT) using deep learning technology. The analysis includes exploring the correlation between novel quantitative indicators, leopard spot fundus grades, and various systemic and ocular parameters. Methods: This was a cross-sectional study. The data were sourced from the Beijing Eye Study, a population-based longitudinal study. In 2001, a group of individuals aged 40 and above were surveyed in five urban communities in Haidian District and three rural communities in Daxing District of Beijing. A follow-up was conducted in 2011. This study included individuals aged 50 and above who participated in the second 5-year follow-up in 2011, considering only the data from the right eye. Color fundus images centered on the macula of the right eye were input into the leopard spot segmentation model and macular detection network. Using the macular center as the origin, with inner circle diameters of 1 mm, 3 mm, and outer circle diameter of 6 mm, fine segmentation of the fundus was achieved. This allowed the calculation of the leopard spot density (FTD) and leopard spot grade for each region. Further analyses of the differences in ocular and systemic parameters among different regions' FTD and leopard spot grades were conducted. The participants were categorized into three refractive types based on equivalent spherical power (SE): myopia (SE<-0.25 D), emmetropia (-0.25 D≤SE≤0.25 D), and hyperopia (SE>0.25 D). Based on axial length, the participants were divided into groups with axial length<24 mm, 24-26 mm, and>26 mm for the analysis of different types of FTD. Statistical analyses were performed using one-way analysis of variance, Kruskal-Wallis test, Bonferroni test, and Spearman correlation analysis. Results: The study included 3 369 participants (3 369 eyes) with an average age of (63.9±10.6) years; among them, 1 886 were female (56.0%) and 1, 483 were male (64.0%). The overall FTD for all eyes was 0.060 (0.016, 0.163); inner circle FTD was 0.000 (0.000, 0.025); middle circle FTD was 0.030 (0.000, 0.130); outer circle FTD was 0.055 (0.009, 0.171). The results of the univariate analysis indicated that FTD in various regions was correlated with axial length (overall: r=0.38, P<0.001; inner circle: r=0.31, P<0.001; middle circle: r=0.36, P<0.001; outer circle: r=0.39, P<0.001), subfoveal choroidal thickness (SFCT) (overall: r=-0.69, P<0.001; inner circle: r=-0.57, P<0.001; middle circle: r=-0.68, P<0.001; outer circle: r=-0.72, P<0.001), age (overall: r=0.34, P<0.001; inner circle: r=0.30, P<0.001; middle circle: r=0.31, P<0.001; outer circle: r=0.35, P<0.001), gender (overall: r=-0.11, P<0.001; inner circle: r=-0.04, P<0.001; middle circle: r=-0.07, P<0.001; outer circle: r=-0.11, P<0.001), SE (overall: r=-0.20; P<0.001; inner circle: r=-0.19, P<0.001; middle circle: r=-0.20, P<0.001; outer circle: r=-0.20, P<0.001), uncorrected visual acuity (overall: r=-0.18, P<0.001; inner circle: r=-0.26, P<0.001; middle circle: r=-0.24, P<0.001; outer circle: r=-0.22, P<0.001), and body mass index (BMI) (overall: r=-0.11, P<0.001; inner circle: r=-0.13, P<0.001; middle circle: r=-0.14, P<0.001; outer circle: r=-0.13, P<0.001). Further multivariate analysis results indicated that different region FTD was correlated with axial length (overall: β=0.020, P<0.001; inner circle: β=-0.022, P<0.001; middle circle: β=0.027, P<0.001; outer circle: β=0.022, P<0.001), SFCT (overall: β=-0.001, P<0.001; inner circle: β=-0.001, P<0.001; middle circle: β=-0.001, P<0.001; outer circle: β=-0.001, P<0.001), and age (overall: β=0.002, P<0.001; inner circle: β=0.001, P<0.001; middle circle: β=0.002, P<0.001; outer circle: β=0.002, P<0.001). The distribution of overall (H=56.76, P<0.001), inner circle (H=72.22, P<0.001), middle circle (H=75.83, P<0.001), and outer circle (H=70.34, P<0.001) FTD differed significantly among different refractive types. The distribution of overall (H=373.15, P<0.001), inner circle (H=367.67, P<0.001), middle circle (H=389.14, P<0.001), and outer circle (H=386.89, P<0.001) FTD differed significantly among different axial length groups. Furthermore, comparing various levels of FTD with systemic and ocular parameters, significant differences were found in axial length (F=142.85, P<0.001) and SFCT (F=530.46, P<0.001). Conclusions: The use of deep learning technology enables automatic segmentation and quantification of different regions of theFT, as well as preliminary grading. Different region FTD is significantly correlated with axial length, SFCT, and age. Individuals with older age, myopia, and longer axial length tend to have higher FTD and more advanced FT grades.

Application of aptamer-conjugated graphene oxide for specific enrichment of microcystin-LR in Achatina fulica prior to matrix-assisted laser desorption ionization mass spectrometry

Microcystin-LR (MC-LR), as a hepatotoxin, can cause liver swelling, hepatitis, and even liver cancer. In this study, MC-LR aptamer (Apt-3) modified graphene oxide (GO) was designed to enrich MC-LR in white jade snail (Achatina fulica) and pond water, followed by matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS) analysis. Results indicated that the Apt-3/PEG/GO nanocomposites were highly specific to MC-LR, and the detection limit of MALDI-MS was 0.50 ng/mL. Moreover, the MC-LR can be released from nanocomposites at 75°C, thus, the reuse of Apt-3/PEG/GO is realized. Real sample analysis indicated that the Apt-3/PEG/GO nanocomposites coupled with MALDI-MS were efficient in detecting trace amounts of MC-LR in real samples. With the merits of being low cost, reusable, and easy to besynthesized, this Apt-3/PEG/GO MALDI-MS is expected to be comprehensively applied by anchoring suitable aptamers for different targets.

[Mutation characteristics of angioimmunoblastic T-cell lymphoma: an analysis of 75 cases]

Objective: To investigate the characteristics of gene mutations in angioimmunoblastic T-cell lymphoma (AITL). Methods: Seventy-five AITL cases diagnosed at the Department of Pathology, Ruijin Hospital Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China from June 2021 to June 2023 were included. Their formalin-fixed and paraffin-embedded or fresh tissues were subject to targeted next generation sequencing (NGS). The sequencing data was collected, and the distribution and type of gene mutations were analyzed. Results: 492 potential driver mutations were identified in 74 out of the 84 genes. Targeted sequencing data for the 75 AITL patients showed that the genes with mutation frequencies of ≥10% were TET2 (89.3%), RHOA (57.3%), IDH2 (37.3%), DNMT3A (36.0%), KMT2C (21.3%), PLCG1 (12.0%), and KDM6B (10.7%). There were significant co-occurrence relationships between TET2 and RHOA, TET2 and IDH2, and RHOA and IDH2 gene mutations (P<0.05), respectively, while TET2 and KDM6B gene mutations were mutually exclusive (P<0.05). Conclusions: The study reveals the mutational characteristics of AITL patients using NGS technology, which would provide insights for molecular diagnosis and targeted therapy of AITL.

[Study on transcriptome characteristics of respiratory syncytial virus bronchiolitis in children by RNA sequencing]

To explore the biological characteristics related to the pathogenesis and severity of respiratory syncytial virus (RSV) bronchiolitis by RNA sequencing of white blood cells in children with RSV bronchiolitis. This study is a case-control study. A total of 87 children diagnosed with bronchiolitis and RSV antigen positive and/or RSV nucleic acid positive in the pediatric respiratory department of the Second Affiliated Hospital of Wenzhou Medical University from October 2019 to April 2022 were selected as the case group. The case group was divided into three groups based on the condition: mild, moderate, and severe, and there were two groups according to the presence or absence of atopic symptoms: the atopic group and the non-atopic group, forty healthy children in the same period were selected as the control group. The whole blood leukocyte RNA of the children in the case group and the control group was extracted for RNA sequencing, and the data were analyzed to obtain differentially expressed genes (DEGs). Then, the immunobiological pathways and genes related to the pathogenesis, disease condition, and atopy were screened through Gene Ontology (GO) annotation, Kyoto Gene and Genome Encyclopedia (KEGG) annotation, and protein interaction network (PPI) construction methods. Construct the weighted gene co-expression network analysis (WGCNA) module to identify potential biological indicators related to disease severity.Compared with the control group, the case group had a total of 1 782 DEGs, including 1 586 upregulated genes and 196 downregulated genes. The GO pathway enrichment of DEGs is mainly enriched in molecular functions such as peroxidase activity and oxidoreductase activity. In the cytological components, it is mainly enriched in cytoplasmic vesicle lumen and secretory granule lumen. In biological processes, it is mainly enriched in processes such as neutrophil activation involved in immune responses, neutrophil degranulation, and neutrophil activation. KEGG analysis is mainly concentrated in the signal pathway of the viral protein interaction with cytokine and cytokine receptor. A PPI network was constructed to screen four genes at the core position, including CCL2, IL-10, MMP9 and JUN. The DEGs obtained by comparing different disease groups with the control group are mainly enriched in retrograde endocannabinoid signaling and cell apoptosis pathways. WGCNA analysis showed that the brown module related to oxygen saturation was most closely related to the disease, and its gene was mainly enriched in the RNA helicase retinoic acid inducible gene-I (RIG-I) like receptor signal pathway. There are 230 specific DEGs in the atopic group and 444 in the non-atopic group. KEGG enrichment analysis results show that both groups are enriched to NF-κB signaling pathway, the characteristic does not cause significant changes in immune response and transcriptome characteristics in children with RSV bronchiolitis. In conclusion, neutrophil activation, degranulation pathway and signal pathway of interaction between viral protein and cytokine and cytokine receptor are involved in the immune response of RSV bronchiolitis host. CCL2, IL-10, MMP9 and JUN genes may be associated with the pathogenesis. They might be potential biomarkers related to disease severity in RIG-I like receptors, cell apoptosis, and endogenous cannabinoid related signaling pathways.

Efficacy and Safety of First-line Therapies for Advanced Unresectable Oesophageal Squamous Cell Cancer: a Systematic Review and Network Meta-analysis

AIM

To compare the clinical efficacy and safety of first-line treatments for advanced unresectable oesophageal squamous cell cancer.

MATERIALS AND METHODS

A systematic review and network meta-analysis was carried out by retrieving and retaining relevant literature from databases. The studies were randomised controlled trials comparing first-line treatments for advanced unresectable oesophageal squamous cell cancer. A Bayesian network meta-analysis was used to assess clinical outcomes.

RESULTS

Nine studies including 4499 patients receiving first-line treatments were analysed. For all populations, toripalimab plus chemotherapy tended to provide the best overall survival (hazard ratio 0.58, 95% confidence intervals 0.43-0.78) and sintilimab plus chemotherapy provided the best progression-free survival (0.56, 0.46-0.68). Nivolumab plus chemotherapy presented the best objective response rate (odds ratio 2.45, 1.78-3.42) and camrelizumab plus chemotherapy (0.47, 0.29-0.74) appeared to be the safest. Sintilimab plus chemotherapy (0.55, 0.40-0.75) and nivolumab (0.54, 0.37-0.80) plus chemotherapy had the best overall survival in programmed death ligand 1 (PD-L1) tumour proportion score <1% and ≥1% subgroups. Toripalimab plus chemotherapy (0.61, 0.40-0.93) and pembrolizumab (0.57, 0.43-0.75) were the best in overall survival in combined positive score <10 and ≥10 subgroups, respectively. Toripalimab plus chemotherapy showed the best overall survival in the Asian group; pembrolizumab presented better overall survival in the Asian population than the non-Asian group.

CONCLUSION

Most immunotherapy combined with chemotherapy showed superior clinical benefits and sintilimab plus chemotherapy, toripalimab plus chemotherapy and tislelizumab plus chemotherapy had better comprehensive clinical efficacy. PD-L1 expression detection and ethnicity differences are still of great significance and most suitable regimens varied from each subgroup.

[A multicenter study to test the reliability and validity of the frailty assessment scale for elderly patients with inguinal hernia and to evaluate the value of clinical application]

Objectives: To verify the reliability and validity of the frailty assessment scale for elderly patients with inguinal hernia and to evaluate the value of its clinical application. Methods: A convenience sampling method was used to collect 129 geriatric patients who underwent inguinal hernia surgery from January 2018 to January 2023 in nine hospitals in Liaoning Province. There were 120 males and 9 females, of whom 89 patients were 60 to <75 years old, 33 patients were 75 to <85 years old and 7 patients were ≥85 years old. The 129 patients included 11 elderly patients with inguinal hernia who had recovered from preoperative infection with COVID-19. Statistical methods such as Cronbach's coefficient, Kaiser-Meyer-Olkin test, Bartlett's test, Pearson's correlation analysis, etc. were calculated to verify the reliability indexes such as feasibility, content validity, structural validity, criterion-related validity, internal consistency reliability, and re-test reliability. Taking the 5-item modified frailty index (5-mFI) as the gold standard, the area under the curve was used to analyze the ability of the two scales to predict the occurrence of postoperative acute urinary retention, postoperative delirium, poor incision healing, operative hematoma seroma, and postoperative complications. Results: The frailty assessment scale for elderly patients with inguinal hernia showed good reliability and validity (valid completion rate of 99.2%; item content validity index of 1.000, and the scale content validity index of 1.000; exploratory factor analysis extracted a total of 1 principal component, and factor loadings of each item of 0.565 to 0.873; the AUC for frailty diagnosis using 5-mFI as the gold standard of 0.795 (P<0.01) Cronbach's coefficient of 0.916, retest reliability coefficient of 0.926), it could effectively predict postoperative acute urinary retention, delirium, hematoma seroma in the operative area and total complications (AUC of 0.746, 0.870, 0.806, and 0.738, respectively; all P<0.05), and prediction efficiency was higher than that of 5-mFI (AUC of 0.694, 0.838, 0.626 and 0.641, P<0.05 for delirium only), but both scales were inaccurate in predicting poor incision healing (AUC of 0.519, P=0.913 for the frailty assessment scale and 0.455, P=0.791 for the 5-mFI). Conclusions: The frailty assessment scale for elderly patients with inguinal hernia is reliable and significantly predicts the occurrence of postoperative adverse events in elderly inguinal hernia patients. The scale can also be used for preoperative frailty assessment in elderly patients with inguinal hernia after rehabilitation from COVID-19 infection.

[Analysis of the relationship between PI-RADS scores and the pathological results of targeted biopsy based on MRI]

Objective: To analyze the relationship between Prostate Imaging Reporting and Data System (PI-RADS) scores and the pathological results of transperineal magnetic resonance-ultrasound fusion guided biopsy. Methods: The clinical data, magnetic resonance imaging (MRI) results and prostate puncture biopsies of 517 patients who were assigned to PI-RADS score of 4 or 5 and underwent transperineal magnetic resonance-ultrasound fusion guided biopsy at The First Affiliated Hospital of Nanjing Medical University from June 2019 to March 2022 were retrospectively analyzed. Patients were divided into the PI-RADS 4 and PI-RADS 5 groups according to their PI-RADS scores and were stratified by their prostate specific antigen (PSA) values (PSA<10 ng/ml vs. PSA 10-20 ng/ml). The pathological negative rates from the biopsy, the distribution of the grade groups according to the grading system by World Health Organization/International Society of Urological Pathology (WHO/ISUP), the detection rates of prostate cancer (PCa) and clinically significant prostate cancer (CsPCa)between the groups were compared. Results: 369 patients with a PI-RADS score of 4 and 148 patients with a PI-RADS score of 5 were included in our research. The overall detection rates of PCa and CsPCa were 77.8% (402/517) and 66.7% (345/517), respectively. In the PI-RADS 4 group, patients with prostate negative biopsies or in WHO/ISUP 1, 2, 3, 4, or 5 grade groups accounted for 28.2%, 12.7%, 20.1%, 17.1%, 18.4% and 3.5%, respectively, whereas in the PI-RADS 5 group the rates were 7.4%, 6.8%, 22.3%, 22.3%, 26.4%, and 14.9%, respectively. The difference was statistically significant (P<0.001). The detection rates of PCa and CsPCa in the PI-RADS 4 group [71.8% (265/369) vs. 59.1% (218/369), P<0.001] were lower than those of the PI-RADS 5 group [92.6% (137/148) vs. 85.8% (127/148), P<0.001]. In the PI-RADS 4 group, the proportion of patients classified into WHO/ISUP 4-5 grade groups was lower than that of patients in the PI-RADS 5 group [22.0% (81/369) vs 41.2% (61/148) (P<0.001)]. The detection rates of PCa and CsPCa in the PSA<10 ng/ml stratification were less than that in the PSA 10-20 ng/ml stratification[74.1% (281/379) vs. 87.7% (121/138), P=0.001], and [60.9% (231/379) vs. 82.6% (114/138), P<0.001]. For patients with PSA<10 ng/ml, the detection rates of PCa and CsPCa in the PI-RADS 4 group were less than those in the PI-RADS5 group [70.9% (217/306) vs. 87.7% (64/73), P=0.003], and [56.2% (172/306) vs. 80.8% (59/73), P<0.001]. For those with a PSA value of 10-20 ng/ml, the detection rates of PCa and CsPCa in the PI-RADS 4 group were less than those in the PI-RADS 5 group [76.2% (48/63) vs. 97.3% (73/75), P<0.001], and [73.0% (46/63) vs. 90.7% (68/75), P=0.006]. There were statistically significant differences in the proportions of patients with prostate negative biopsy and those falling into WHO/ISUP grade groups 1, 2, 3, 4, or 5 (P<0.001) between the PI-RADS 4 group and the PI-RADS 5 group in both stratifications. Conclusions: In this study, the detection rates of CsPCa and PCa in the PI-RADS 4 group were less than those in the PI-RADS 5 group. With the increase of PI-RADS scores, the detection rate of high-grade PCa increased. The same results held for patients with PSA<10 ng/ml or with PSA 10-20 ng/ml.

Accuracy of Electron Density Mapping of a Novel kVCBCT System Designed for Planning

PURPOSE/OBJECTIVE(S)

A recently developed advanced kVCBCT system, designed for simulation and planning, includes improvements to the imaging panel and reconstruction technique, enabling more accurate electron density mapping than a typical CBCT. This study investigates the accuracy, limitations, and dosimetric impact of this new system.

MATERIALS/METHODS

CBCT images were taken of both large (pelvis) and small (head) electron density phantoms with inserts ranging from lung (0.29) to cortical bone (1.69). Images were taken with several pre-set protocols with energies of 125 kVp and 140 kVp. The effects of longitudinal buildup (for scatter due to the cone-beam geometry) and blade position were also investigated. The HU values of each insert were measured over a small region of interest. Several electron density curves were generated - pelvis protocol on the large phantom, head protocol on the small phantom, and average - and imported into a treatment planning system. Dose calculation was performed using each curve and differences were observed.

RESULTS

HU to electron density mapping was sensitive to the use of longitudinal buildup and blade position, with differences in the curves observed at both low and high electron densities, due to imager saturation effects not found in typical clinical scenarios. Subsequent studies used both longitudinal buildup and fully opened blades. Under these conditions, mapping was not sensitive to technique or phantom size at low electron densities. At higher values, the curves diverged, with the head protocol showing higher HU values and the pelvis protocol showing lower. The average curve matched very closely with the curve from our standard CT simulator. Dose calculation showed little dependence on the curve chosen, with max point dose differences of 1.2% between the pelvis and average scans, though most of the plan was <0.5% different. Results for the head protocol were similar.

CONCLUSION

The system provides reliable HU values comparable to a CT simulator, though it is important to consider the effects of imager saturation by choosing appropriate scatter and collimation. The calibration is slightly sensitive to the choice of phantom size and beam energy, though these differences led to negligible (<0.5%) differences in dose calculation accuracy.

ACR Accreditation of a Novel Linac-Based kV-CBCT System on a High-Speed Ring-Gantry

PURPOSE/OBJECTIVE(S)

An advanced kV-CBCT imaging system mounted on a high-speed ring-gantry Linac has recently been introduced, offering improved imaging hardware and reconstruction software to produce high quality CBCT images usable for treatment planning. Imaging performance of the system was assessed using the American College of Radiology (ACR) accreditation designed for diagnostic CT systems, additionally comparing its results to pre-existing diagnostic CT and Linac-based CBCT systems.

MATERIALS/METHODS

All imaging protocols on the novel imaging system were scanned with the ACR head phantom and evaluated using ACR recommended testing and passing criteria. ACR image quality parameters include contrast-to-noise ratio (CNR), spatial resolution, HU accuracy, image scaling, and HU uniformity. CNR ≥1.0 for adult head and body, ≥0.7 for pediatric head, and ≥0.4 for pediatric body imaging protocols pass ACR criteria. Spatial resolution ≥6 line-pairs/cm for head and ≥5 line-pairs/cm for body protocols pass ACR criteria. HU accuracy passing criteria includes acrylic (110 to 135 HU), air (-1005 to -970 HU), bone (850 to 970 HU), polyethylene (-107 to -84 HU), and water (-7 to 7 HU). Image scaling measurements with errors ≤5% and HU uniformity maximum differences ≤5 HU pass ACR criteria. For machine cross-comparisons, adult Head and Pelvis imaging protocols were acquired on an existing diagnostic CT and 2 Linac-based CBCT systems (1 traditional C-arm and 1 ring-gantry) and analyzed with the same ACR methodology and passing criteria, with passing rates compared.

RESULTS

On the novel imaging system, all standard patient size imaging protocols using 125 kVp (Head, H&N, Thorax, Thorax Slow, Breast, Abdomen, Pelvis, Pediatric Head, and Pediatric Abdomen) passed all ACR criteria; while 2 larger patient focused imaging protocols using 140 kVp (Abdomen Large and Pelvis Large) produced minor deviations on HU uniformity (maximum differences of 5 - 7 HU) but passed all other ACR criteria. The novel system matched passing rates of a diagnostic CT simulator, and outperformed pre-existing Linac based CBCT imaging systems.

CONCLUSION

This newly developed advanced imaging system produces high quality images, meeting diagnostic CT ACR recommendations and far surpassing the CBCT image quality currently available on pre-existing Linacs.

Lymphocyte Count Kinetics and the Effect of Different Radiotherapy Techniques on Radiation-Induced Lymphopenia in Patients with Breast Cancer Receiving Hypofractionated Postmastectomy Radiotherapy

PURPOSE/OBJECTIVE(S)

Radiation-induced lymphopenia (RIL) is associated with poor prognosis in solid tumors. This study aimed to describe the lymphocyte kinetics in patients with breast cancer receiving hypofractionated postmastectomy radiotherapy (RT) and to investigate the association of different RT techniques with RIL.

MATERIALS/METHODS

We assessed 607 patients who received hypofractionated postmastectomy RT for breast cancer in our prospective clinical database from 8 hospitals. All patients received irradiation to the chest wall and supraclavicular fossa. RT techniques included integrated RT with the photon-based intensity modulated techniques to irradiate all target volumes (integrated RT) and a hybrid approach combining photon irradiation to supraclavicular nodes and electron irradiation to the chest wall (hybrid RT). Peripheral lymphocyte counts (PLC) were tested prior to RT (baseline), weekly during RT, at 1, 2 weeks, 3, 6 months after RT, and then every 6 months. Grade 3+ RIL was defined as PLC nadir during RT of <0.5 ×103/ml. Mean PLC was compared by the t test. Univariate, multivariate, and propensity score matching (PSM) analyses were used to evaluate the effect of different RT techniques on grade 3+ RIL.

RESULTS

During RT, 121 (19.9%) of patients had grade 3+ RIL. The PLC started to recover at 1 week and reached baseline levels 1 year after RT. A greater proportion of the patients treated with the integrated RT (90/269, 33.5%) developed grade 3+ PLC compared with those receiving hybrid RT (31/338, 9.2%, P < 0.001). After conducting PSM, multivariate analyses showed lower baseline PLC (HR = 0.15, P<0.001) and RT technique (the integrated RT vs. hybrid RT, HR = 4.76, P<0.001) were independent risk factors for grade 3+ RIL. The PLC in patients receiving the integrated RT after RT were higher than that in those receiving hybrid RT (p<0.05).

CONCLUSION

RT technique affect the risk of and recovery from RIL, which may impact survival. Choosing appropriate RT technique to minimize RIL might be considered to benefit their outcomes.

Dose-Volume Predictors for Radiation Esophagitis in Breast Cancer Patients Undergoing Hypofractionated Regional Nodal Radiotherapy

PURPOSE/OBJECTIVE(S)

Radiation esophagitis (RE) is often overlooked in breast cancer radiotherapy. This study aimed to assess the incidence and dose-volume predictors of RE in breast cancer patients undergoing hypofractionated regional nodal irradiation (RNI).

MATERIALS/METHODS

Eligible patients were included who received intensity-modulated radiotherapy (RT) at the chest wall, the supraclavicular/infraclavicular fossa, level II axilla, and/or the internal mammary chain after mastectomy. The prescribed dose was 43.5 Gy in 15 fractions. The dose constraint for the esophagus was maximum dose <48 Gy. RE was evaluated weekly during RT and at 1 and 2 weeks, followed by 3 and 6 months after RT, and was graded according to the Common Toxicity Criteria for Adverse Events v3.0. The esophagus was contoured from the lower border level of the cricoid cartilage to the lower margin of the aortic arch. Esophageal total volume, mean dose (Dmean), maximum dose (Dmax), and the relative and absolute volumes receiving at least 5-45 Gy by 5 Gy increments (RV5-RV45 and AV5-AV45) were evaluated. Univariable and multivariable logistics regression analyses were performed to determine risk factors for RE, and receiver operating characteristic curves were obtained to identify the thresholds of esophageal dosimetric parameters.

RESULTS

In total, 298 patients were included between May 8, 2020 and January 5, 2022 (minimum post-RT follow-up: 6 months). A total of 153 (51.3%) patients had left-sided breast cancer and 145 (48.7%) patients received internal mammary nodal irradiation (IMNI). Grade 2 and 3 RE incidence was 40.9% (122/298) and 0.3% (1/298), respectively. No grade 4 or 5 RE was observed. All RE cases resolved within 1 month after RT, and the median duration of RE was 3 weeks (range, 1-5). Based on univariable analyses, tumor laterality (p < .001), IMNI (p = .056) and esophageal Dmean, Dmax, RV10-RV40, and AV10-AV40 were risk factors of ≥grade 2 RE. Esophageal RV10-RV40 and AV35-AV40 were significantly associated with the risk of ≥grade 2 RE after adjusting for tumor laterality and IMNI. Based on multivariable analyses, RV25 and AV35 were optimum dose-volume predictors for ≥grade 2 RE at thresholds 20% for RV25 (35.9% vs. 60.9%, p = .04) and 0.27 mL for AV35 (31.0% vs. 54.6%, p = .04).

CONCLUSION

RE is common in breast cancer patients undergoing hypofractionated RNI. With the same esophageal contouring standard, maintaining the upper esophageal V25 at <20% and V35 at <0.27 mL may decrease the risk of RE and improve the quality of life of patients.

Quality Assurance in a Phase III, Multicenter, Randomized Trial of POstmastectomy radioThErapy in Node posiTive Breast Cancer with or without Internal mAmmary nodaL Irradiation (POTENTIAL): A Planning Dummy Run

PURPOSE/OBJECTIVE(S)

To report the planning dummy run results of the POstmastectomy radioThErapy in Node posiTive breast cancer with or without Internal mAmmary nodaL irradiation (POTENTIAL) trial-a multicenter, randomized, phase 3 trial-to evaluate postmastectomy radiotherapy, with or without internal mammary nodal irradiation, for patients with high-risk breast cancer.

MATERIALS/METHODS

All participating institutions were provided the contours of the dummy run case, and they generated radiotherapy (RT) plans per protocol guidelines. The plans were reviewed and feedback were provided by the quality assurance team, after which the institutions resubmitted revised plans. The information on beams arrangement, skin flash, inhomogeneity corrections, and protocol compliance was assessed both in the primary and final submission.

RESULTS

Theplans from 26 institutions were included in the analysis. A number of major deviations were found in the primary submission, such as less strict constraint on organs at risk (OARs) V5Gy, and no application of chest wall skin flash. The protocol compliance rates of the dose coverage for the planning target volume of the chest wall (PTVcw), PTV of supra/infraclavicular fossa plus axilla levels I, II, III (PTVsc+ax), and PTV of the IMN region (PTVim) were all significantly improved in the final submission compared with those in the primary submission, which were 96.2% vs. 69.2%, 100% vs. 76.9%, and 88.4% vs. 53.8, respectively. For OARs, the protocol compliance rates of heart Dmean, left anterior descending coronary artery V40Gy, ipsilateral lung V5Gy, and stomach V5Gy were significantly improved.

CONCLUSION

All major deviations were corrected and protocol compliance was significantly improved and of high level in the final submission. Moreover, the variations were reduced. Therefore, a planning dummy run was essential to guarantee good RT plan quality and inter-institutional consistency for multicenter trials.

[Application of genetic counseling and preventive surgery in hereditary breast-ovarian cancer syndrome based on a rare family]

Objective: To investigate the genetic, clinical and pathological characteristics of families with hereditary breast-ovarian cancer syndrome (HBOCS) and to explore the implementation of genetic counseling and preventive surgery. Methods: Four siblings with HBOCS in Cancer Hospital/Chinese Academy of Medical Sciences were selected as the study subjects. BRCA gene testing and genetic counseling were performed, family history was traced and family map was drawn. Results: There were 7 cancer patients (Ⅰ 2, Ⅱ 4, Ⅱ 8, Ⅲ 7, Ⅲ 10, Ⅲ 11, Ⅲ 12) in three generations in the family. One patient (Ⅲ 7) had breast cancer and ovarian cancer successively. The first generation (Ⅰ 2) developed cancer at age 60, the second generation (Ⅱ4 and Ⅱ8) developed cancer at 55. The third generation (Ⅲ 7, Ⅲ 10, Ⅲ 11, Ⅲ 12) developed cancer at the age of 42-50 years. Four HBOCS patients were treated in our hospital, and all of them were found to have deleterious BRCA1 mutation. Two had already developed ovarian cancer (Ⅲ 10, Ⅲ 12), while in one case (Ⅲ 11), tubal carcinoma was found during preventive total hysterectomy and pelvic lymph node metastasis was found after the supplementary staging surgery. The other patient without cancer underwent preventive bilateral salpingectomy(Ⅲ 15). Conclusion: The HBOCS family reported in this study is relatively rare, the onset time of tumor was younger generation by generation. It is very important to pay attention to the genetic counseling of ovarian cancer patients and to timely detect the HBOCS families for genetic testing and prophylactic surgery.

[The target value of anticoagulation intensity for Chinese patients after mechanical heart valve replacement]

Objective: To explore the optimal intensity of anticoagulation therapy for Chinese patients after mechanical heart valve replacement. Methods: This is a prospective, multicenter, cohort study. The anticoagulation data from in-hospital patients of 35 medical centers and patients in outpatient clinic of 11 medical centers from Anticoagulation Therapy Database of Chinese Patients after Heart Valve Replacement between January 2011 and December 2015 were analyzed. The anticoagulation-relevant complications among different coagulation intensities were compared, and the optimal value of anticoagulation intensity for Chinese patients after mechanical heart valve replacement were analyzed. Results: A total of 24 433 patients were in the final analysis, including 13 634 females and 10 799 males, with a median age of 49.0 (3-80) years. International normalized ratio (INR) values of in-hospital patients were recorded 94 286 times, with the mean value of 1.8±0.7, and 87.6% (82 595/94 286) of them were within the range of 1.5 to 2.5. During a median follow-up time of 19.2 (1.0-58.8) months, a total of 17 331 outpatient clinic patients were followed up, with the follow-up rate of 89.1% (17 331/19 452) and a total of 27 803 patient-years (Pty), including 4 038 aortic valve replacement (AVR), 8 215 mitral valve replacement (MVR), 4 437 AVR plus MVR (double valve replacement, DVR) replacement and 641 tricuspidvalve replacement (TVR). A total of 101 860 INR measurements were recorded, with the mean value of 1.8±0.5, and 64.8% (66 005/101 860) of them were within the range of 1.5-2.5. The rates of anticoagulation-related complications of the patients with INR of 1.5-2.5 (0.65/100 Pty) were lower than those of other INR value patients (INR<1.5: 1.31/100 Pty, RR=2.01, 95%CI: 1.59-2.51, P<0.001; INR>2.5: 2.34/100 Pty, RR=3.60, 95%CI: 2.84-4.52, P<0.001). The rates of anticoagulation-related complications of AVR and MVR patients without risk factors and with INR of 1.5-2.0 were lower than those of other INR value patients (AVR: 0.15/100 Pty vs 0.38/100 Pty, RR=2.57, 95%CI: 1.02-7.28, P=0.029; MVR: 0.23/100 Pty vs 0.56/100 Pty, RR=2.42, 95%CI: 1.39-4.38, P<0.001), and the rate of anticoagulation-related complications of DVR patients with INR of 2.0-2.5 was lower than those of other INR value patients (0.32/100 Pty vs 0.62/100 Pty, RR=1.94, 95%CI: 1.03-3.79, P=0.029). Conclusions: A target INR range of 1.5-2.5 is recommended for Chinese patients after mechanical heart valve replacement. The optimal INR value for isolated AVR or MVR patients without risk factors was 1.5-2.0, while the optimal INR value for isolated AVR or MVR patients with risk factors and all the TVR or DVR patients was 2.0-2.5.

[Clinicopathologic characteristics and prognostic analysis of testicular diffuse large B-cell lymphoma]

Objective: To analyze the clinicopathologic characteristics and prognosis of testicular diffuse large B-cell lymphoma (DLBCL) . Methods: A retrospective analysis was performed on 68 patients with testicular DLBCL admitted to Ruijin Hospital affiliated to Shanghai Jiao Tong University School of Medicine from October 2001 to April 2020. The gene mutation profile was evaluated by targeted sequencing (55 lymphoma-related genes) , and prognostic factors were analyzed. Results: A total of 68 patients were included, of whom 45 (66.2% ) had primary testicular DLBCL and 23 (33.8% ) had secondary testicular DLBCL. The proportion of secondary testicular DLBCL patients with Ann Arbor stage Ⅲ-Ⅳ (P<0.001) , elevated LDH (P<0.001) , ECOG score ≥ 2 points (P=0.005) , and IPI score 3-5 points (P<0.001) is higher than that of primary testicular DLBCL patients. Sixty-two (91% ) patients received rituximab in combination with cyclophosphamide, adriamycin, vincristine, and prednisone (R-CHOP) -based first-line regimen, whereas 54 cases (79% ) underwent orchiectomy prior to chemotherapy. Patients with secondary testicular DLBCL had a lower estimated 5-year progression-free survival (PFS) rate (16.5% vs 68.1% , P<0.001) and 5-year overall survival (OS) rate (63.4% vs 74.9% , P=0.008) than those with primary testicular DLBCL, and their complete remission rate (57% vs 91% , P=0.003) was also lower than that of primary testicular DLBCL. The ECOG scores of ≥2 (PFS: P=0.018; OS: P<0.001) , Ann Arbor stages Ⅲ-Ⅳ (PFS: P<0.001; OS: P=0.018) , increased LDH levels (PFS: P=0.015; OS: P=0.006) , and multiple extra-nodal involvements (PFS: P<0.001; OS: P=0.013) were poor prognostic factors in testicular DLBCL. Targeted sequencing data in 20 patients with testicular DLBCL showed that the mutation frequencies of ≥20% were PIM1 (12 cases, 60% ) , MYD88 (11 cases, 55% ) , CD79B (9 cases, 45% ) , CREBBP (5 cases, 25% ) , KMT2D (5 cases, 25% ) , ATM (4 cases, 20% ) , and BTG2 (4 cases, 20% ) . The frequency of mutations in KMT2D in patients with secondary testicular DLBCL was higher than that in patients with primary testicular DLBCL (66.7% vs 7.1% , P=0.014) and was associated with a lower 5-year PFS rate in patients with testicular DLBCL (P=0.019) . Conclusion: Patients with secondary testicular DLBCL had worse PFS and OS than those with primary testicular DLBCL. The ECOG scores of ≥2, Ann Arbor stages Ⅲ-Ⅳ, increased LDH levels, and multiple extra-nodal involvements were poor prognostic factors in testicular DLBCL. PIM1, MYD88, CD79B, CREBBP, KMT2D, ATM, and BTG2 were commonly mutated genes in testicular DLBCL, and the prognosis of patients with KMT2D mutations was poor.

[Analysis of the clinical features and the risk factors of severe human metapneu movirus-associated community acquired pneumonia in children]

Objective: To investigate the clinical characteristics and the risk factors of severe human metapneumovirus (hMPV)-associated community acquired pneumonia (CAP) in children. Methods: A retrospective case summary was conducted. From December 2020 to March 2022, 721 children who were diagnosed with CAP and tested positive for hMPV nucleic acid by PCR-capillary electrophoresis fragment analysis of nasopharyngeal secretions at the Yuying Children's Hospital, the Second Affiliated Hospital of Wenzhou Medical University were selected as the research objects. The clinical characteristics, epidemiological characteristics and mixed pathogens of the two groups were analyzed. According to CAP diagnostic criteria, the children were divided into the severe group and the mild group. Chi-square test or Mann-Whitney rank and contrast analysis was used for comparison between groups, while multivariate Logistic regression was applied to analyze the risk factors of the severe hMPV-associated CAP. Results: A total of 721 children who were diagnosed with hMPV-associated CAP were included in this study, with 397 males and 324 females. There were 154 cases in the severe group. The age of onset was 1.0 (0.9, 3.0) years, <3 years old 104 cases (67.5%), and the length of hospital stay was 7 (6, 9) days. In the severe group, 67 children (43.5%) were complicated with underlying diseases. In the severe group, 154 cases (100.0%) had cough, 148 cases (96.1%) had shortness of breath and pulmonary moist rales, and 132 cases (85.7%) had fever, 23 cases (14.9%) were complicated with respiratory failure. C-reactive protein (CRP) was elevated in 86 children (55.8%), including CRP≥50 mg/L in 33 children (21.4%). Co-infection was detected in 77 cases (50.0%) and 102 strains of pathogen were detected, 25 strains of rhinovirus, 17 strains of Mycoplasma pneumoniae, 15 strains of Streptococcus pneumoniae, 12 strains of Haemophilus influenzae and 10 strains of respiratory syncytial virus were detected. Six cases (3.9%) received heated and humidified high flow nasal cannula oxygen therapy, 15 cases (9.7%) were admitted to intensive care unit, and 2 cases (1.3%) received mechanical ventilation. In the severe group, 108 children were cured, 42 children were improved, 4 chlidren were discharged automatically without recovery and no death occurred. There were 567 cases in the mild group. The age of onset was 2.7 (1.0, 4.0) years, and the length of hospital stay was 4 (4, 6) days.Compared with the mild group, the proportion of children who age of disease onset <6 months, CRP≥50 mg/L, the proportions of preterm birth, congenital heart disease, malnutrition, congenital airway malformation, neuromuscular disease, mixed respiratory syncytial viruses infection were higher (20 cases (13.0%) vs. 31 cases (5.5%), 32 cases (20.8%) vs. 64 cases (11.3%), 23 cases (14.9%) vs. 44 cases (7.8%), 11 cases (7.1%) vs. 18 cases (3.2%), 9 cases (5.8%) vs. 6 cases (1.1%), 11 cases (7.1%) vs. 12 cases (2.1%), 8 cases (5.2%) vs. 4 cases (0.7%), 10 cases (6.5%) vs. 13 cases (2.3%), χ²=0.42, 9.45, 7.40, 4.94, 11.40, 8.35, 3.52, 6.92, all P<0.05). Multivariate Logistic regression analysis showed that age<6 months (OR=2.51, 95%CI 1.29-4.89), CRP≥50 mg/L (OR=2.20, 95%CI 1.36-3.57), prematurity (OR=2.19, 95%CI 1.26-3.81), malnutrition (OR=6.05, 95%CI 1.89-19.39) were the independent risk factors for severe hMPV-associated CAP. Conclusions: Severe hMPV-associated CAP is most likely to occur in infants under 3 years old and has a higher proportion of underlying diseases and co-infection. The main clinical manifestations are cough, shortness of breath and pulmonary moist rales, fever. The overall prognosis is good. Age<6 months, CRP≥50 mg/L, preterm birth, malnutrition are the independent risk factors for severe hMPV-associated CAP.

Maize resistance to witchweed through changes in strigolactone biosynthesis

Maize (Zea mays) is a major staple crop in Africa, where its yield and the livelihood of millions are compromised by the parasitic witchweed Striga. Germination of Striga is induced by strigolactones exuded from maize roots into the rhizosphere. In a maize germplasm collection, we identified two strigolactones, zealactol and zealactonoic acid, which stimulate less Striga germination than the major maize strigolactone, zealactone. We then showed that a single cytochrome P450, ZmCYP706C37, catalyzes a series of oxidative steps in the maize-strigolactone biosynthetic pathway. Reduction in activity of this enzyme and two others involved in the pathway, ZmMAX1b and ZmCLAMT1, can change strigolactone composition and reduce Striga germination and infection. These results offer prospects for breeding Striga-resistant maize.

[Bibliometric analysis of publications pertaining to artemisinin resistance in Plasmodium falciparum based on Web of Science from 2011 to 2022]

OBJECTIVE

To analyze the global literature output and citation of publications pertaining to artemisinin (ART) resistance in Plasmodium falciparum from 2011 to 2021, so as to provide insights into researches on resistance of P. falciparum to ART.

METHODS

The publications pertaining to ART resistance in P. falciparum were retrieved from the Science Citation Index Expanded (SCIE) database in Web of Science during the period from January 2011 through May 2022. The subject, journal, country, affiliation and author distributions and citations of publications were descriptively analyzed.

RESULTS

A total of 1 640 publications pertaining to ART resistance in P. falciparum were retrieved in the SCIE database during the period from January 2011 through May 2022, and the number of publications appeared an overall tendency towards a rise during the study period. These articles were published in 343 journals, and the three most productive journals included Malaria Journal (341 publications, 20.79%), Antimicrobial Agents and Chemotherapy (141 publications, 8.60%), American Journal of Aropical Medicine and Hygiene (68 publications, 4.15%), with infectious diseases (565 publications, 34.45%), parasitology (531 publications, 32.38%), and tropical medicine (517 publications, 31.54%) as the predominant subject. The three most productive countries included the United States of America (627 publications, 38.23%), United Kingdom (395 publications, 24.08%), and Thailand (294 publications, 17.94%), with total citations of 25 280, 18 622 and 15 474, respectively, and the most productive countries included Mahidol University (Thailand), Oxford University (England) and London University (England), with 234, 220 publications and 142 publications and 15 058, 15 421 citations and 6 191 citations, respectively. The three most productive authors were all from Mahidol University, with 85, 77 and 63 publications, respectively; and among the three most cited authors, two were from Mahidol University, Thailand, with 8 623 and 7 961 total citations, and one from National Institutes of Health, the United States of America, with 6 267 total citations. A total of 138 articles were published by Chinese scientists, with 3 434 total citations, and National Institute of Parasitic Diseases of Chinese Center for the Diseases Control and Prevention was the most productive Chinese institution, with 35 publications, 1 165 total citations and 33.29 citations per publication.

CONCLUSIONS

The literature output of ART resistance in P. falciparum was relatively high in the United States of America, Europe, and Southeast Asian countries during the period from 2011 to 2021, with a relatively high academic impact. Publications in Malaria Journal and Antimicrobial Agents and Chemotherapy are recommended to be paid much attention by Chinese scientists to understand the latest advances and extend the research interests.

Rapid quasi-periodic oscillations in the relativistic jet of BL Lacertae

Blazars are active galactic nuclei (AGN) with relativistic jets whose non-thermal radiation is extremely variable on various timescales^1-3. This variability seems mostly random, although some quasi-periodic oscillations (QPOs), implying systematic processes, have been reported in blazars and other AGN. QPOs with timescales of days or hours are especially rare⁴ in AGN and their nature is highly debated, explained by emitting plasma moving helically inside the jet⁵, plasma instabilities^6,7 or orbital motion in an accretion disc^7,8. Here we report results of intense optical and γ-ray flux monitoring of BL Lacertae (BL Lac) during a dramatic outburst in 2020 (ref. ⁹). BL Lac, the prototype of a subclass of blazars¹⁰, is powered by a 1.7 × 10⁸ M_Sun (ref. ¹¹) black hole in an elliptical galaxy (distance = 313 megaparsecs (ref. ¹²)). Our observations show QPOs of optical flux and linear polarization, and γ-ray flux, with cycles as short as approximately 13 h during the highest state of the outburst. The QPO properties match the expectations of current-driven kink instabilities⁶ near a recollimation shock about 5 parsecs (pc) from the black hole in the wake of an apparent superluminal feature moving down the jet. Such a kink is apparent in a microwave Very Long Baseline Array (VLBA) image.