Using MRI Radiomics to Predict the Efficacy of Immunotherapy for Brain Metastasis in Patients with Non-small Cell Lung Cancer

PURPOSE/OBJECTIVE(S)

Despite immune checkpoint inhibitors (ICIs) has been proven effective in patients with advanced NSCLC, controversial therapeutic responses are seen in brain metastatic lesions. There are no robust biomarkers that predict benefit from this regimen. We evaluated the utility of novel imaging biomarkers (radiomics) to distinguish NSCLC patients with brain metastases (BMs) who will benefit from ICIs from those likely to progress despite therapy.

MATERIALS/METHODS

One-hundred and seventy-four NSCLC Patients with BMs treated with ICIs from June 2019 - June 2022 were identified. We collected patient clinical outcomes and pre-treatment MRI images. Images were split into training and test sets. Brain metastatic lesions were contoured on ITK-SNAP software and 3748 radiomic features capturing both intra- and peritumoral texture patterns were extracted. The primary endpoint of this study was intracranial progression-free survival (iPFS) and the secondary objective were progression-free survival (PFS) and overall survival (OS). We used the least absolute shrinkage and selection operator (LASSO) Cox regression model to build the radiomic signature for ORR. Based on the support vector machine (SVM) model, we construct the Clinical-radiomics nomogram (CRN). Multivariable Cox regression analysis were performed to evaluate the effect of each factor on iPFS. We performed Kaplan-Meier survival analysis and log-rank tests to assess prognostic value of the features.

RESULTS

We identified 174 patients who fit our criteria with available MRI images. 122 patients treated in our center were divided into a training set and 52 patients treated in another center were divided into a test set. The intratumoral radiomic signatures(IRS), peritumoral radiomic signatures(PRS) and CRN showed favorable predictive effects for ORR with the area under the receiver operating curve (AUC) of (IRS: 0.845 (95% CI: 0.776-0.914); PRS: 0.799 (95% CI:0.720-0.879); CRN:0.907 (95% CI: 0.855-0.959))in the training set and (IRS: 0.809 (95% CI: 0.693-0.926); PRS: 0.749 (95% CI:0.616-0.883); CRN:0.888(95% CI:0.798-0.979)) in the test set. Kaplan-Meier analyses showed a significantly longer iPFS in the high-CRN group versus the low-CRN group (P < 0.001). The CRNs were also found significantly associated with PFS (P < 0.001), but not OS.

CONCLUSION

Radiomic biomarkers from pre-treatment MRI images in NSCLC patients with BMs were predictive of iPFS to ICIs. Pre-treatment radiomics may allow early prediction of benefit and expedite more aggressive treatment for high-risk patients. Additional validation of these imaging biomarkers is warranted.

Influence of Eyes Movement on Lens Dose during MR-Guided Radiotherapy for Brain Tumor

PURPOSE/OBJECTIVE(S)

Modern radiotherapy techniques achieve highly conformal target doses while avoiding organs at risk such as lens. The magnitude of eyes movement and its influence on lens dose is unclear. The lens dose is relevant for cataract formation. This study aims to evaluate the movement-range of lens and its influence on dose distribution during MR-guided radiotherapy for brain cancer patients.

MATERIALS/METHODS

Fifty patients with brain cancer who were treated with MR-guided radiotherapy on 1.5 T MR-Linac were included in this study. All patients underwent a pre-treatment MRI and post-treatment MRI for each fraction. The eyes and lens were delineated on each MR image by a radiation oncologist. The reference treatment plans based original CT were recalculated on each MRI by "adapt to position" workflow. Then, we created planning risk volume (PRV) for lens by adding population margin and reoptimized the reference plans to evaluate the dose changes for lens. Inter-fraction and intrafraction variability for eyes and lens were evaluated with the Dice similarity coefficient (DSC), the Hausdorff distance (HD) and mean distance to agreement (MDA). Differences in daily dose (Dmax and Dmean) for eyes and lens were assessed.

RESULTS

A total of 300 MR images were analyzed in this study. The eyes motion was observed (minimum DSC: 0.57; maximum HD: 10.53; maximum MDA: 3.13). And the obvious lens motion also was found (minimum DSC: 0.01; maximum HD: 10.78; maximum MDA: 5.68). The maximum dose changes for eyes were up to 34.1% and the mean dose changes were up to 18.1%. The maximum dose changes for lens were up to 97.9% and the mean dose changes for eyes were up to 89%. When the reoptimized plans were generated by PRV lens, the dose changes were decreased nearly to 0.

CONCLUSION

Eyes movements in all radiotherapy fractions result in higher lens doses and potentially increase cataract formation rate. Adding margin expansions in treatment planning, to account for eyes motion, is the feasible approach to limit lens dose.

Antibacterial Activity of a Lysin LysP53 against Streptococcus mutans

Dental caries is a common disease affecting quality of life globally. In the present study, we found that a bacteriophage lysin LysP53 against Acinetobacter baumannii possesses selective activity on Streptococcus mutans, the main etiological agent of dental caries, even in low pH caries microenvironments, whereas only minor LysP53 activity was detected against Streptococcus sanguinis, Streptococcus oralis, and Streptococcus mitis. Testing activity against S. mutans planktonic cells showed that 4 μM LysP53 could kill more than 84% of S. mutans within 1 min in buffer with optimal pHs ranging from 4.0 to 6.5. Daily application of LysP53 on biofilms formed in BHI medium supplemented or not with sucrose could reduce exopolysaccharides, expression of genes related to acid resistance and adhesion, and the number of live bacteria in the biofilms. LysP53 treatment also showed similar effects as 0.12% chlorhexidine in preventing enamel demineralization due to S. mutans biofilms, as well as effective removal of S. mutans colonization of tooth surfaces in mice without observed toxic effects. Because of its selective activity against main cariogenic bacteria and good activity in low pH caries microenvironments, it is advantageous to use LysP53 as an active agent for preventing caries.

Computational explorations of the interaction between laccase and bisphenol A: influence of surfactant and different organic solvents

Bisphenol A (BPA), as an environmental endocrine disruptor can cause damage to the reproductive, nervous and immune systems. Laccase can be used to degrade BPA. However, laccase is easily deactivated, especially in organic solvents, but the specific details are not clear. Molecular dynamics simulations were used to investigate the reasons for changes in laccase activity in acetonitrile (ACN) and dimethyl formamide (DMF) solutions. In addition, the effects of ACN and DMF on the activity of laccase and surfactant rhamnolipid (RL) on the degradation of BPA by laccase were investigated. Results showed that addition of ACN changed the structure of the laccase, not only decreasing the van der Waals interaction that promoted the binding of laccase with BPA, but also increasing the polar solvation free energy that hindered the binding of laccase with BPA, so it weakened the laccase activity. DMF greatly enhanced the van der Waals interaction between laccase and BPA, and played a positive role in their binding. The addition of surfactant RL alleviated the effect of organic solvent on the activity of laccase by changing the polar solvation energy. The mechanism of surfactant RL affecting laccase activity in ACN and DMF is described, providing support for understanding the effect of organic solvents on laccase.

Efficacy and Toxicity of Different Target Volume Delineations of Radiotherapy Based on the Updated RTOG/NRG and EORTC Guidelines in Patients with High Grade Glioma: A Randomized, Controlled Clinical Trial

PURPOSE/OBJECTIVE(S)

Postoperative radiotherapy with concomitant and adjuvant temozolomide (TMZ) is the standard of care for newly diagnosed high grade glioma, but the optimal method for target volume delineations for intensity modulated radiation therapy (IMRT) is still unclear. We hypothesized that compared with the EORTC guidelines, IMRT based on the updated RTOG/NRG guidelines was equally effective, without increasing toxicities for patients with high-grade glioma. The purpose of this randomized phase 2 study was to compare the efficacy and toxicity of IMRT based on different target volume delineations (updated RTOG/NRG versus EORTC guidelines) with concomitant and adjuvant TMZ for patients with high grade glioma.

MATERIALS/METHODS

A total of 302 patients with newly diagnosed high-grade glioma (WHO grade 3-4) were randomly assigned (1:1) to receive postoperative IMRT based on either updated RTOG/NRG guidelines (RTOG/NRG group, n = 151) or EORTC guideline (EORTC group, n = 151), with concomitant and adjuvant TMZ. In the RTOG/NRG group, an initial volume consisting of enhancement, postoperative cavity, plus surrounding edema (or fluid-attenuated inversion recovery [FLAIR] abnormality defined by magnetic resonance imaging [MRI]) and a 2-cm margin received 46 Gy in 23 fractions followed by a boost of 14 Gy in 7 fractions to the area of enhancement plus the cavity and a 2-cm margin. In the EORTC group, a single planning volume was used to deliver 60 Gy in 30 fractions to the area of enhancement and the cavity with a 2-cm margin. The primary end point was overall survival (OS). Secondary end points included progression-free survival (PFS) and toxicities associated with each treatment.

RESULTS

No statistically significant differences were observed between groups for 1-year OS (71.8% for RTOG/NRG group and 69.9% for EORTC group, respectively; P = 0.759) or 1-year PFS (46.7% for RTOG/NRG group and 43.6% for EORTC group, respectively; P = 0.674). Efficacy did not differ by MGMT methylation status. There were no differences in grade 3-4 toxicities (leukopenia, lymphopenia, neutropenia, thrombocytopenia, fatigue, nausea and vomiting) between the two groups. No grade 5 toxicities were observed in both groups. Multivariate analyses showed that tumor MGMT status (methylated vs unmethylated) and WHO grade (grade 3 vs grade 4) were associated with OS and PFS. However, radiation type (RTOG/NRG group vs EORTC), sex, age, and Karnofsky scale did not significantly influence OS or PFS.

CONCLUSION

Compared with EORTC guidelines for postoperative radiotherapy, IMRT based on RTOG/NRG guidelines was equally effective, without increasing toxicities for patients with high-grade glioma. This trial is registered with chictr.org.cn, number ChiCTR2100046667.

Effects of the PARP Inhibitor Niraparib on the Radiosensitivity of Human Lung and Cervical Cancer Cells

PURPOSE/OBJECTIVE(S)

DNA damage repair (DDR) initiated after DNA damage may lead to a decreased radiosensitivity of tumor cells or even radiation resistance. Previous studies indicate that PARP inhibitors block the repair of DNA single-strand breaks (SSBs), and unrepaired SSBs may continuously accumulate and form double-strand breaks (DSBs) that promotes tumor cell death. Studies have also shown that PARP inhibitors act synergistically with RT to inhibit DDR. In this study, we aim to investigate the effect of Niraparib, a clinically approved PARP inhibitor on the radiosensitivity of human lung and cervical cancer cells, and preliminarily explore the underlying mechanism.

MATERIALS/METHODS

The human lung cancer cell line A549 and human cervical cancer cell line Siha were both treated with niraparib (for 1h), or X-ray (4Gy), or Niraparib (for 1h) combined with X-ray (4Gy). The effect was examined via measurements of cell proliferation by the cell counting kit-8 assay, and cell viability was detected by clone formation assays. Cell apoptosis and cell cycle distribution were investigated by flow cytometry.

RESULTS

In human lung and cervical cancer cell lines, Niraparib combined with radiation therapy significantly inhibited cell proliferation. The proportion of apoptotic cells in cell lines treated with Niraparib plus radiation (the combination group) was significantly higher compared with control, radiation-only, and Niraparib-only groups. Additionally, the proportion of A549 cells in the G2/M phase was significantly increased in the combination group compared with the radiation-only group.

CONCLUSION

The results support that PARP inhibitor Niraparib increases the radiosensitivity of tumor cells, promotes their apoptosis, and induces cell cycle redistribution. The possible mechanism is associated with the inhibition of radiation-induced DNA damage repair.

Cost-Effectiveness of Short-Course Radiotherapy Based Total Neoadjuvant Therapy for Locally Advanced Rectal Cancer in China

PURPOSE/OBJECTIVE(S)

The phase III STELLAR (NCT02533271) trial demonstrated that four cycles of chemotherapy after short-course radiotherapy (SCRT-TNT) were not inferior to the standard care of long-course concurrent radiotherapy (LCRT) in patients with locally advanced rectal cancer (LARC). This study assessed the cost-effectiveness of SCRT-TNT versus LCRT in locally advanced rectal cancer in China on the basis of the STELLAR trial.

MATERIALS/METHODS

A Markov model was used to synthesize the healthcare costs and benefits of LARC patients based on results from the STELLAR trial. The model assumes that LARC who meet the inclusion criteria of the STELLAR trial experience four possible states: No Evidence of Disease (NED), locally recurrence, distant metastases, or any death from rectal cancer or other unrelated causes, where local recurrence continues to be classified as resectable and unresectable. The transition status period is 3 month, and 5 years is used to calculate direct medical costs and health benefits. The probabilities of states transition after SCRT-TNT or LCRT were derived from the results of the STELLAR trial and previous published article (Table.1). Costs were evaluated from the Chinese payer's perspective reported in early 2022 US dollars (US$1 = 6.78 Chinese Yuan). Sensitivity analyses were performed for key variables. Cost-effectiveness was evaluated using the incremental cost-effectiveness ratio and net monetary benefits. Effectiveness was defined as quality-adjusted life-years (QALYs). Willingness-to-pay (WTP) threshold was set at $43500/QALY. Data were collected from October 3, 2020, to September 20, 2021, and analyzed from November 15, 2020, to October 25, 2021.

RESULTS

During the 5-year horizon, for the base case scenario, SCRT-TNT incurred a lower total cost and higher QALYs compared with LCCRT. The total cost was $65767 and QALYs were 1.77 for SCRT-TNT; for LCCRT, the total cost was $72802 and QALYs were 1.64. This resulted in an ICER of -$ 55470.69 per QALY. Therefore, SCRT-TNT was a cost-saving and dominating treatment strategy compared with LCRT. Sensitivity analysis showed that ICERs were most sensitive to the parameters of distant metastases risk after treatment.

CONCLUSION

SCRT-TNT in locally advanced rectal cancer can be a cost-effective alternative to LCRT in China, and should be considered in appropriately selected patients.

4D-MRI Guided Stereotactic Body Radiation Therapy for Unresectable Colorectal Liver Metastases

PURPOSE/OBJECTIVE(S)

This study evaluated the feasibilities and outcomes following four-dimensional magnetic resonance imaging (4D-MRI) guided stereotactic body radiation therapy (SBRT) for unresectable colorectal liver metastases (CRLM).

MATERIALS/METHODS

From March 2018 to January 2022, we identified 76 unresectable CRLM patients with 123 lesions who received 4D-MRI guided SBRT in our institution. 4D-MRI simulation with or without abdominal compression was conducted for all patients. The prescription dose was 50-65 Gy in 5-12 fractions. The image quality of computed tomography (CT) and MRI were compared using the Clarity Score. Clinical outcomes and toxicity profiles were evaluated.

RESULTS

The 4D-MRI significantly improved the image quality compared with CT images (mean Clarity Score: 1.67 vs 2.88, P < 0.001). The abdominal compression significantly reduced motions in cranial-caudal direction (P = 0.03) with 2 phase T2 weighted images assessing tumor motion. The median follow-up time was 12.5 months. For 98 lesions assessed for best response, the complete response, partial response and stable disease rate were 57.1 %, 30.6 % and 12.2 %, respectively. The local control (LC) rate at 2 year was 97.3%. 46.1% of patients experienced grade 1-2 toxicities and only 2.6% patients experienced grade 3 hematologic toxicities.

CONCLUSION

The 4D-MRI technique allowed precise target delineation and motion tracking in unresectable CRLM patients. High LC rate and mild toxicities were achieved. This study provided evidence for using 4D-MRI guided SBRT as an alternative treatment in unresectable CRLM.

Using MRI Radiomics to Predict the Efficacy of Immunotherapy for Brain Metastasis in Patients with Small Cell Lung Cancer

PURPOSE/OBJECTIVE(S)

Immune-checkpoint inhibitors (ICIs) combined with chemotherapy has been widely used in the first-line treatment of small cell lung cancer (SCLC) patients. However, the efficacy of ICIs for patients with brain metastases (BMs) of SCLC is limited. There are no effective factors to predict the efficacy. We developed and validate a model to predict intracranial efficacy for ICIs in patients with BMs from SCLC by using MRI radiomics.

MATERIALS/METHODS

In this study, we collected 101 SCLC patients with BMs treated with ICIs. They clinical characteristics and pre-treatment Magnetic Resonance Imaging (MRI) were collected. Seventy cases collected from our hospital as training cohort and 31 cases collected from another hospital as an independent validation cohort. Brain metastatic lesions were contoured on ITK-SNAP software and 3748 radiomic features capturing both intra- and peritumoral texture patterns were extracted. The primary endpoint of this study was intracranial overall response rate (ORR). Intraclass correlation coefficient (ICC) and random forest (RF) model were used to select radiomic features. The top 10 selected radiomic features were adopted to build prognostic models by using logistic regression. Area Under the Curve (AUC) of the Receiver Operating Characteristic (ROC) was chosen as the metric to assess model performances. We also performed a nomogram based on a multivariate logistic regression model includes radiomic and clinical features to predict ICIs intracranial efficacy.

RESULTS

The clinical characteristics including number of treatment lines and concurrent brain radiotherapy, ten intratumoral signatures and one peritumoral signatures were found significantly associated with ICIs intracranial efficacy. Predictors contained in the individualized prediction nomogram included the radiomics signature, and clinical features. The model showed favorable discrimination with a C-index of 0.861[95% CI: 0.779-0.943] and AUC of 0.861[95% CI: 0.778- 0.944] in training cohort and with a C-index of 0.812[95% CI: 0.647-0.978] and AUC of 0.812[95% CI:0.646-0.979] in the test cohort.

CONCLUSION

Radiomic features from pre-treatment MRI images were predictive for intracranial efficacy in SCLC patients with BMs. Pre-treatment radiomics may allow early prediction of benefit and expedite more aggressive treatment for high-risk patients and it has to be further explored as predictor of outcome in a larger series of patients.

Chemoradiotherapy Combined with Nab-Paclitaxel plus Cisplatin in Patients with Locally Advanced Borderline Resectable or Unresectable Esophageal Squamous Cell Carcinoma: A Phase I/II Study

PURPOSE/OBJECTIVE(S)

To evaluate the efficacy and safety of nanoparticle albumin-bound paclitaxel (nab-PTX) plus cisplatin as the regimen of conversional chemoradiotherapy (cCRT) in locally advanced borderline resectable or unresectable esophageal squamous cell carcinoma (ESCC).

MATERIALS/METHODS

Patients with locally advanced ESCC (cT3-4, Nany, M0-1, M1 was limited to lymph node metastasis in the supraclavicular area) were enrolled. All the patients received the cCRT of nab-PTX plus cisplatin. After the cCRT, those resectable patients received esophagectomy; those unresectable patients continued to receive the definitive chemoradiotherapy (dCRT). The locoregional control (LRC), overall survival (OS), progression-free survival (PFS), distant metastasis free survival (DMFS), pathological complete response (pCR), R0 resection rate and adverse events (AEs) were calculated.

RESULTS

A total of 45 patients with ESCC treated from October 2019 to May 2021 were finally included. The median follow-up time was 30.3 months. The LRC, OS, EFS, DMFS at 1and 2 years were 81.5%, 86.6%, 64.3%, 73.2% and 72.4%, 68.8%, 44.8%, 52.7% respectively. 21 patients (46.7%) received conversional chemoradiotherapy plus surgery (cCRT+S). The pCR rate and R0 resection rate were 47.6% and 84.0%. The LRC rate at 1 and 2 years were 95.0%, 87.1% in cCRT+S patients and 69.3%, 58.7% in dCRT patients respectively (HR, 5.14; 95% CI, 1.10-23.94; P = 0.021). The OS rate at 1 and 2 years were 95.2% and 84.2% in resectable patients compared to 78.8% and 54.4% in unresectable patients (HR, 3.41; 95% CI, 1.10-10.61; P = 0.024). The toxicities during chemoradiotherapy were tolerated, the most common grade 3-4 toxicities were radiation esophagitis (15.6%).

CONCLUSION

Nab-PTX plus cisplatin were effective and safe as the regimen of conversional chemoradiotherapy of ESCC. The patients receiving conversional chemoradiotherapy plus surgery (cCRT+S) were prone to have a better survival.

CREB3L2 Regulates Hemidesmosome Formation during Epithelial Sealing

The long-term success rate of dental implants can be improved by establishing a favorable biological sealing with a high-quality epithelial attachment. The application of mesenchymal stem cells (MSCs) holds promise for facilitating the soft tissue integration around implants, but the molecular mechanism is still unclear and the general application of MSC sheet for soft tissue integration is also relatively unexplored. We found that gingival tissue-derived MSC (GMSC) sheet treatment significantly promoted the expression of hemidesmosome (HD)-related genes and proteins in gingival epithelial cells (GECs). The formation of HDs played a key role in strengthening peri-implant epithelium (PIE) sealing. Further, high-throughput transcriptome sequencing showed that GMSC sheet significantly upregulated the PI3K/AKT pathway, confirming that cell adhesion and HD expression in GECs were regulated by GMSC sheet. We observed that the expression of transcription factor CREB3L2 in GECs was downregulated. After treatment with PI3K pathway inhibitor LY294002, CREB3L2 messenger RNA and protein expression levels were upregulated. Further experiments showed that overexpression or knockdown of CREB3L2 could significantly inhibit or promote HD-related genes and proteins, respectively. We confirmed that CREB3L2 was a transcription factor downstream of the PI3K/AKT pathway and participated in the formation of HDs regulated by GMSC sheet. Finally, through the establishment of early implant placement model in rats, we clarified the molecular function of CREB3L2 in PIE sealing as a mechanical transmission molecule in GECs. The application of GMSC sheet-implant complex could enhance the formation of HDs at the implant-PIE interface and decrease the penetration distance of horseradish peroxidase between the implant and PIE. Meanwhile, GMSC sheet reduced the length of CREB3L2 protein expression on PIE. These findings elucidate the potential function and molecular mechanism of MSC sheet regulating the epithelial sealing around implants, providing new insights and ideas for the application of stem cell therapy in regenerative medicine.

Recovery Characteristics of Lymphocyte Subsets after Thoracic Radiotherapy: A Single Center Clinical Study

PURPOSE/OBJECTIVE(S)

Lymphocytes play a critical role in anti-tumor, and are highly sensitive to radiation. However, the dynamic changes of lymphocytes subsets after receiving thoracic radiotherapy have rarely been investigated. This study was to explore the recovery characteristics of each subset, and the role of thymosin α1 after thoracic radiotherapy.

MATERIALS/METHODS

A total of 252 patients receiving chest radiotherapy included in this study. Blood was harvested before, at the end of radiotherapy, 1 month, 4 months, 7 months, 10 months, 13 months, and 19 months after radiotherapy for lymphocyte subsets detection by performing flow cytometry. In addition, a total of 26 patients with thoracic malignancy were treated with thymosin α1 after radiotherapy for one month. The number of lymphocyte subsets at the end of 1 month after radiotherapy were compared with control group. Absolute counts method was used in flow cytometry.

RESULTS

At the end of radiotherapy, nearly all of the subsets decreased significantly (T cell: 65.4%, Tc cell: 64.8%, Th cell: 66.1%, B cell: 88.7%, NK cell: 68.8%), except Treg cell. Tc cells recovered rapidly to baseline level at 1 month. The number of NK cells increased by 1.95 times at 1 month, and recovered to baseline level at 7th month. The number of B cell at 1 month was still 19.2% compared baseline, and recovered slowly to baseline at 7th month. The number of Th cells were nearly no recovery, and were 44.1% compared with baseline even at 19th month. For patients with thymosin α1 injection, all of the lymphocyte subsets had no significant difference compared those without thymosin α1 injection. In addition, younger patients were with better recovery in Th cells (p = 0.011) and B cells (p < 0.001) than elder patients at 1 month.

CONCLUSION

B cell was the most radiosensitive lymphocyte, and Th cell was continuous exhaustion after thoracic radiation. Thymosin α1 had no effect on lymphocyte subpopulation recovery, and new drugs are urgently needed to explore in the future.

Crowdsourcing Deep Learning Algorithms to Automatically Contour GI Luminal Organs on Serial MRIs

PURPOSE/OBJECTIVE(S)

A major barrier to a sustainable real-time adaptive MR-guided radiotherapy workflow is the time-consuming process of contouring the target and organs-at-risk (OARs) before the delivery of each fraction. While auto-contouring algorithms perform relatively well for many solid organs, the performance on luminal organs in the abdomen remain difficult due to the variability between patients and variability in daily shape and position. The purpose of this study is to evaluate the performance of crowdsourced deep learning algorithms to automatically contour GI luminal organs on serial MRIs.

MATERIALS/METHODS

The stomach, small intestines, and large intestines were manually contoured on MRIs from patients who had undergone radiotherapy on an MR-Linac by a team of radiation therapists and medical physicists and were verified by a board-certified radiation oncologist. The MRIs and the contours were de-identified and uploaded to Kaggle, an online machine learning competition platform with portion of the data open to the public as training data and the remaining data hidden as a test set. Prize money was offered to teams submitting the best auto-contouring algorithms based on the Dice coefficient and Hausdorff distance evaluation metrics. The average performance of the winning algorithm and of manual contours were compared using unpaired t-test.

RESULTS

Four hundred sixty-seven MRIs were collected from 107 patients who underwent 1-5 serial MRI sessions between 2015 and 2019. The most common anatomic site of treatment was the pancreas with 41 patients, followed by the liver with 38 patients. The manual contours of the stomach, small intestines, and large intestines on 4 representative MRIs had mean and standard deviation Dice coefficient of 0.90 +/- 0.02, 0.76 +/- 0.04, and 0.85 +/- 0.03 respectively and Hausdorff distance of 18.0 +/- 6.9, 35.5 +/- 12.6, and 32.3 +/- 12.3 mm respectively. The Kaggle competition was held from April to July 2022 and 1548 teams submitted algorithms for evaluation. The auto-contouring performance of the winning solution on the stomach, small intestines, and large intestines, when evaluated on a hold-out test set with 188 MRIs, had mean and standard deviation Dice coefficient of 0.92 +/- 0.04, 0.80 +/- 0.09, 0.85 +/- 0.08 respectively and Hausdorff distance of 15.2 +/- 11.2, 33.9 +/- 15.2, 34.8 +/- 20.3 mm respectively. Unpaired t-test was performed to compare the average performance across three organs of the human (N = 120) and of the algorithm (N = 564). The results suggest that average algorithm performance was statistically superior to manual contours for Dice (p = 0.01), yet not for Hausdorff (p = 0.64).

CONCLUSION

Crowdsourced deep learning algorithms to auto-contour GI luminal organs on serial MRIs perform superiorly compared to manual contours when using a Dice coefficient metric but not when using a Haudorff distance metric. These auto-contouring algorithms may be used to efficiently adapt radiotherapy plans according to the anatomy of the day for patients with abdominal tumors on MR-Linacs.

[Clinical characteristics of aplastic anemia patients with abnormal autoantibodies and the impact of autoantibodies on immunosuppressive therapy response]

Objective: To investigate the clinical characteristics of patients with acquired aplastic anemia (AA) accompanied by abnormal antinuclear antibody (ANA) and autoantibodies and their effects on the efficacy of immunosuppressive therapy (IST). Method: A retrospective case-control study was conducted, analyzing the clinical data of 291 patients with AA who underwent IST and were screened for autoantibodies at initial diagnosis between January 2018 and December 2019 at Blood Diseases Hospital, Chinese Academy of Medical Sciences. According to the titer of ANA at the initial diagnosis, extracted nuclear antigen antibodies (ENAs) abnormality and the change of ANA titer after treatment, the treatment responses of 3 months and 6 months after IST were compared. The correlation between clinical features and ANA abnormality was analyzed by univariate and multivariate logistic regression analysis. The parameters of univariate analysis P<0.1 were included in multivariate analysis, stepwise regression analysis and subgroup analysis. Results: A total of 291 patients were included in the study, of which 145 (49.83%) were male. Among all patients, 147 (50.52%) tested positive for ANA at initial diagnosis, with titers of 1∶100, 1∶320, and 1∶1 000 observed in 94, 47, and 6 cases, respectively. Female gender, older age, presence of paroxysmal nocturnal hemoglobinuria (PNH) clone, and higher levels of IgG, IgA, and thyroid hormone were significantly associated with ANA positivity at initial diagnosis, while white cell counts, reticulocytes, and free triiodothyronine were significantly lower than that of ANA-negatively patients (all P<0.05). Furthermore, logistic regression analyses revealed that female gender (OR=1.980, 95%CI 1.206-3.277), older age (OR=1.017, 95%CI 1.003-1.032), and presence of PNH clone (OR=1.875, 95%CI 1.049-3.408) were independent risk factors for ANA positivity at initial diagnosis. Subgroup analysis indicated that the risk of ANA positivity at initial diagnosis was even higher in PNH clone-positive patients in the subgroups of females (OR=1.24, 95%CI 1.02-1.51), severe AA (OR=1.26, 95%CI 1.07-1.47), and age≥40 years (OR=1.26, 95%CI 1.05-1.52) (all P<0.05). However, ANA titers at initial diagnosis, presence of other abnormal ENAs, and changes in ANA titers after treatment with IST were not correlated with treatment response (all P>0.05). Conclusions: Approximately 50% of patients with AA had abnormal ANA, and their presence was significantly associated with female gender, older age, and presence of PNH clone at initial diagnosis. However, the presence of abnormal ANA and changes in ANA titers after treatment did not affect the efficacy of IST in patients with AA.

Association of Overall Survival Benefit Profile of Radiotherapy with Progression-Free Survival after Chemotherapy for Diffuse Large B-Cell Lymphoma

PURPOSE/OBJECTIVE(S)

Benefit of radiotherapy (RT) after chemotherapy (CT) of diffuse large B-cell lymphoma (DLBCL) remains controversial. It is unknown whether improved progression-free survival (PFS) by RT translate into an overall survival (OS) benefit. To address this question, our research comprehensively evaluated the risk-benefit assessment of RT in DLBCL through an in-depth examination of previously reported data from randomized controlled trials (RCTs) and retrospective comparative studies.

MATERIALS/METHODS

After screening and quality control, this study included 7 randomized controlled trials and 52 retrospective studies of combined-modality therapy (CMT) versus CT alone. The correlation between PFS and OS was evaluated using the Pearson linear correlation coefficient at trial- and study arm-level. A risk-benefit assessment to describe the OS benefit of RT was performed in meta-analyses of pooled HROS with PFS patterns.

RESULTS

In RCTs, strong correlations were found between HRPFS and HROS at trial-level (r = 0.876), and PFS and OS at treatment arm-level, regardless of treatments (r = 0.945-0.964 for all, CMT or CT). In retrospective studies, similar correlations between HRPFS and HROS (r = 0.639-0.650), and PFS and OS rates (r = 0.882-0.910) were observed, independent of treatments or rituximab. Adding RT into rituximab-based CT increased the average PFS rate from 63.6 ± 18.9% to 81.5 ± 10.6% (P<0.001), with differential OS benefits of RT between studies. Patients can be stratified into four PFS patterns (>80%, >60-80%, >40-60%, and ≤40%); absolute gain in OS from RT ranged from ≤5% at PFS >80% to ∼21% at PFS ≤40%, with pooled-HROS from 0.70 (95% CI, 0.51-0.97) to 0.48 (95% CI, 0.36-0.63) after rituximab-based CT. Linear analysis revealed an OS advantage of CMT over CT alone in a PFS-dependent manner.

CONCLUSION

We demonstrate a varied OS benefit profile of RT upon different PFS patterns, and provide valuable evidence for making treatment decisions and designing clinical trials. Future strategies to select the use of RT will need careful tailoring in clinical practice or within RCT to optimize outcome.

Weighted gene co-expression network analysis of key targets and interventional mechanism of Milkvetch root in diabetic nephropathy

OBJECTIVE

This work aimed to explore the key targets and intervention mechanisms of Huangqi (Astragalus membranaceus) in diabetic nephropathy using weighted gene co-expression network analysis (WGCNA). The findings will provide references for identifying critical therapeutic targets for diabetic nephropathy.

MATERIALS AND METHODS

The GSE1009 dataset was selected from the Gene Expression Omnibus (GEO) database of the National Center for Biotechnology Information (NCBI) for analysis. WGCNA network was constructed to identify differentially expressed genes (DEGs). Gene ontology (GO) and pathway enrichment analysis were performed on the DEGs.

RESULTS

There were 752 downregulated DEGs and 1,547 upregulated DEGs in the diabetic nephropathy samples. Genes such as PLCE1, CLIC5, PTPRO, HSPA12A, AIF1, GMDS, and SEMA5A were significantly suppressed in the diabetic nephropathy samples, while genes such as CEP152, LUNAR1, and SLC9A1 were significantly upregulated. The optimal soft threshold for the WGCNA network was determined as 12. Hierarchical clustering analysis was conducted to detect co-expression modules with corresponding color assignments, and a total of 9 modules were identified. Clinical characteristics showed a high correlation with the gray, blue, green, and brown modules of the WGCNA. GO analysis and KEGG pathway enrichment analysis revealed that the blue module DEGs were mainly enriched in immune response, inflammatory response, signal transduction, plasma membrane, extracellular region, cell surface, extracellular matrix, and proteinaceous extracellular matrix. The green module DEGs were mainly enriched in mitochondrial elongation, mitochondrial mutation termination, translation, mitochondrial inner membrane, mitochondrion, ATP biosynthetic process, mitochondrial large ribosomal subunit, mitochondrial intermembrane space, nucleolus, and ribosome. Visualization analysis of the bioactive components of Huangqi showed compounds such as quercetin, resveratrol, 7-O-methylisomucronulatol, and isoquercetin, which had more targets.

CONCLUSIONS

Differentially expressed genes in diabetic nephropathy were mainly enriched in immune response and inflammatory response. Various components of Huangqi have positive application value in the treatment of diabetic nephropathy and can be considered for clinical promotion.

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.

Distribution Pattern of Metastatic Lymph Nodes in 870 Cases of Nasopharyngeal Carcinoma: A Clue for Individualized Elective Prophylactic Neck Irradiation

PURPOSE/OBJECTIVE(S)

We aimed to explore a potential individualized elective prophylactic neck irradiation (iEPNI) to optimize the current strategy by investigating the distribution of metastatic lymph nodes (LNs) in nasopharyngeal carcinoma (NPC).

MATERIALS/METHODS

Magnetic resonance imaging (MRI) and clinical data of 870 non-distant metastatic NPC patients admitted to the Hunan Cancer Hospital between January 2019 and December 2019 were reviewed. All patients were staged using the 8th TNM staging system, and the LNs location was assigned based on the 2013 guidelines. According to the distribution patterns of the LNs in NPC, the intra-regional lymphatic drainage levels were categorized into the following three stations: Station 1st of level VIIa and II; Station 2nd of level III and Va; and Station 3rd of level IV, Vb, and Vc. Other levels were defined as extra-regional areas.

RESULTS

The incidence of LNs metastasis was 822/870 (94.5%), including 198 cases of unilateral metastasis and 624 cases of bilateral metastasis. Among the 870 patients, the most frequently involved intra-regional lymphatic drainage was level IIb (87.1%), followed by level VIIa (80.0%), IIa (61.8%), Va (30.6%), IV (21.4%), Vb (8.9%), and Vc (1.1%). In the extra-regional areas, the detailed LNs distribution was: level Ia (0.2%), level Ib (7.7%), level VI (0.1%), level VIIb (5.6%), level VIII (5.5%), level IX (0.3%), and level X (0.2%). The rates of LNs metastasis in Station 1st, Station 2nd, and Station 3rd were 820/870 (94.3%), 532/870 (61.1%), and 199/870 (22.9%), respectively. Only 4 patients were considered to be skipping metastasis among the three stations (4/870, 0.5%). Additionally, in 203 patients with unilateral Station 1st LNs metastasis, there were 86 (42.4%) and 37 (18.2%) patients with ipsilateral Station 2nd and Station 3rd metastasis, respectively, and 3 (1.5%) and 1 (0.5%) patients with contralateral Station 2nd and Station 3rd LNs metastasis, respectively.

CONCLUSION

LNs spread from Station 1st to Station 3rd successively with rare skipping metastasis. A potential iEPNI strategy of prophylactical neck irradiation to the ipsilateral latter node-negative station might be feasible, which is detailed as follows: irradiation to Station 1st in patients with no LNs metastasis, irradiation to Station 2nd in patients with only Station 1st metastasis, and irradiation to Station 3rd in patients with Station 2nd metastasis but without Station 3rd metastasis. Further prospective investigations are expected to validate the strategy.

Tumor Treatment Response Assessed During the Chemo-Radiotherapy for Locally Advanced NSCLC

PURPOSE/OBJECTIVE(S)

To evaluate the capability of assessing intratumoral treatment response distribution with using FDG-PET/CT during the chemoradiotherapy of locally advanced NSCLC.

MATERIALS/METHODS

Twelve of total 50 patients with stage III NSCLC were enrolled in the institutional protocol for concurrent chemoradiotherapy with treatment dose of 54-60 Gy in 27-30 fractions. For each patient, a pre-treatment FDG-PET/CT image (SUV0) and a mid-treatment image (SUVm) obtained within the treatment dose of 24 ∼ 46 Gy were obtained. Followed by deformable PET/CT registration between SUV0 and SUVm, the tumor voxel SUV reduction ratio was obtained to construct a tumor dose response matrix (DRM). Tumor SUVavid was also constructed by limiting tumor voxel SUVm > a given value. Spatial correlations of the tumor SUV0, SUVm, SUVavid and DRM were determined.

RESULTS

The mean and coefficient variation (CV) of the SUV0, SUVm and DRM for all tumors were 6.56(64%), 2.82(59%) and 0.52(70%) (Table contains the individual data), which were like those on the SUVs and the mean DRM of head-neck HPV- patients reported previously, but much larger on the DRM variation. The inter-tumoral CVs of SUV0 and DRM were 17% and 43%, which were much smaller than those of the intra-tumoral CVs 61% and 55%. Meanwhile, the intra-tumoral variations on both SUV0 and DRM were much larger than those of head-neck HPV- patients. There was a weak correlation between SUV0 and SUVm with the correlation coefficient 0.32, a medium correlation of -0.51 between SUV0 and DRM; 0.58 between SUVm and DRM. It implies that the rule of tumor dose response DRM on treatment modification decision cannot be fully replaced by either SUV0 or SUVm. The spatial correlation between tumor DRM and SUVavid was 0.23 with SUVavid value > 3, which was getting weaker when increasing SUVavid value.

CONCLUSION

Spatial dose response for NSCLC assessed using FDG-PET/CT feedback demonstrated high treatment resistant patterns, which had a large intra-tumoral variation. In addition, the medium correlations of DRM vs SUV0 and DRM vs SUVm imply that all these factors could be used to guide adaptive modification of NSCLC treatment.

Hybrid Immuno-RT for Bulky Tumors: Standard Fractionation with Partial Tumor SBRT

PURPOSE/OBJECTIVE(S)

Bulky tumors remain challenging to be treated. Stereotactic body radiation therapy (SBRT) is effective against radioresistant tumor cells and can induce immunogenic cell death (ICD) that leads to T-cell-mediated antitumor effects. Low-dose radiation (LDRT) can inflame the tumor microenvironment (TME) by recruiting T cells. We designed a novel radiotherapy technique (RT, ERT) whose dose distribution map resembles the "eclipse" by concurrently delivering LDRT to the whole tumor, meanwhile SBRT to only a part of the same tumor. This study examined the safety and efficacy of ERT to bulky lesions with PD-1 inhibitors in mice and patients.

MATERIALS/METHODS

In mice with CT26 colon or LLC1 lung bulky tumors (400 - 500 cm3), the whole tumor was irradiated by LDRT (2 Gy x 3), meanwhile the tumor center was irradiated by SBRT (10 Gy x 3); αPD-1 was given weekly. The dependence of therapeutic effects on CD8+ T cells was determined using depleting antibodies. Frequencies of CD8+ T cells and M1 macrophages (Mφ) were determined by flow cytometry. Multiplex Immunohistochemistry (mIHC) was applied to analyze the number and the location of CD8+ T cells and their subpopulations, as well as the phospho-eIF2α level (the ICD marker) of tumor cells in TME. Patients with advanced lung or liver bulky tumors who failed standard treatment or with oncologic emergencies were treated. Kaplan-Meier method was applied to estimate patients' progression-free survival (PFS) and overall survival (OS).

RESULTS

ERT/αPD-1 is superior to SBRT/αPD-1 or LDRT/αPD-1 in controlling bulky tumors in both mouse models in a CD8+ T-cell dependent manner. In the CT26 model, ERT/αPD-1 resulted in complete tumor regression in 3/11 mice and induced more CD8+ T cells and M1 Mφ in TME compared to other groups. mIHC analysis showed that ERT/αPD-1 induced higher bulk, stem-like (TCF1+ TIM3- PD-1+), and more differentiated (TCF1- TIM3+ PD-1+) CD8+ T cells infiltration into the tumor center and periphery compared to other groups. Compared to untreated or LDRT-treated tumor centers, tumor centers irradiated with ERT or SBRT showed elevated phospho-eIF2α accompanied by higher dendritic cell infiltration. In total, 39 advanced cancer patients were treated with ERT/αPD-1 or plus chemotherapy. Radiation-induced pneumonitis occurred in 1 of 26 patients receiving thoracic ERT. There were two cases of grade III toxicity associated with PD-1 inhibitors. No toxicity above grade III was observed. The objective response rate was 38.5%. The median PFS was 5.6 months and median OS was not reached at a median follow-up of 11.7 months.

CONCLUSION

ERT/αPD-1 showed superior efficacy in controlling bulky tumor in two mouse models. The hybrid immuno-RT (ERT) combing PD-1 inhibitors was safe and effective in patients with bulky tumors. Further clinical trials in combination with bioimaging to identify the optimal SBRT target region for the bulky tumor are warranted.

Outcomes of Consolidative Thoracic Radiation within First-Line Chemoimmunotherapy in Extensive-Stage Small-Cell Lung Cancer: Results from a Single Cancer Center

PURPOSE/OBJECTIVE(S)

Thoracic radiation (TRT) benefits local control undoubtedly and survival with some minor controversy in extensive-stage small-cell lung cancer (ES-SCLC) patients undergoing radiotherapy in the chemoradiotherapy era. However, whether TRT could further enhance the benefit of immune checkpoint inhibitors (ICIs) maintenance on outcomes in the immunotherapy era is still unclear. This study aims to investigate the role of consolidative TRT in ES-SCLC patients receiving first-line chemoimmunotherapy followed by immunotherapy maintenance.

MATERIALS/METHODS

Outcomes of patients who were treated with first-line chemo-immunotherapy followed by ICIs maintenance for ES-SCLC were reviewed. Based on TRT or not, patients were allocated to TRT group or non-TRT group. Progression-free survival (PFS), overall survival (OS) and local-recurrence free survival (LRFS) were calculated by the Kaplan-Meier method and compared by log-rank test.

RESULTS

A total of 100 patients with no progressive disease after 4 cycles of chemotherapy were retrospectively analyzed between January 2020 and December 2021 and were allocated into TRT group (n = 47) and non-TRT group (n = 53). The median follow-up time was 20.3 months. The median PFS and OS in TRT were 9.1 months and 21.8 months, versus 8.8 months (p = 0.93) and 24.3 months (p = 0.63), respectively, in non-TRT. ICIs agents consisted of Durvalumab (59.0%) and Atezolizumab (41.0%). The median dose of TRT is 50 Gy (IQR: 45 - 54), while the median interval time from chemotherapy completion to TRT was 31 days (IQR: 12 - 44.5). Only 10 (21.3%) patients terminated ICIs in the period of TRT. The rate of intrathoracic progression after the first-line therapy in TRT significantly decreased compared to that with non-TRT (20.0% versus 55.9%, p = 0.003). The median LRFS time in TRT was not reached, but significantly longer than 10.8 months in non-TRT (HR = 0.27, p < 0.01). Second-line chemotherapy significantly prolonged survival compared to that with chemo-free patients (mOS: 24.5 vs. 21.4 months, p = 0.026). The subgroup analysis showed a trend of patients with brain metastases benefit from TRT (21.8 versus 13.7 months, HR 0.61, p = 0.38) while liver metastases did not (13.3 versus 15.0 months, HR 1.80, p = 0.21). Of 47 patients with TRT, only 10.6% of patients experienced grade 3 radiation-induced pneumonitis, while no grade 4 or 5 adverse events occurred. None of patients experienced grade ≥ 3 treatment-related cardiac events.

CONCLUSION

Consolidative TRT in the period of immunotherapy maintenance followed first-line chemo-immunotherapy did not prolong OS and PFS but increased LRFS in ES-SCLC.

Development and Validation of a Nomogram for Patients with Lung Large Cell Neuroendocrine Carcinoma

PURPOSE/OBJECTIVE(S)

Pulmonary large cell neuroendocrine carcinoma (LCNEC) is a rarely high-grade neuroendocrine carcinoma of the lung with features of both small cell and non-small cell lung cancer. We aim to construct a prognostic nomogram combined with the clinical features and treatment options to predict disease-specific survival (DSS), meanwhile, evaluating the role of prophylactic cranial irradiation (PCI) in LCNEC by subgroup analysis.

MATERIALS/METHODS

A total of 713 patients diagnosed with LCNEC from the US National Cancer Institute's Surveillance Epidemiology and End Results (SEER) registry between 2010 and 2016. Cox proportional hazards analysis was conducted to choose the significant predictors of DSS. External validation was performed using 77 patients with LCNEC in the West China Hospital Sichuan University between 2010 and 2018, subgroup analysis was carried out for the whole brain radiotherapy (WBRT) and PCI population. The predictive accuracy and discriminative capability were estimated by the concordance index (C-index), calibration curve and receiver operating characteristic (ROC) curve. The clinical applicability of the nomogram was verified through the decision curve analysis (DCA).

RESULTS

Six independent risk factors for DSS were identified and integrated into the nomogram. The nomogram achieved good C- indexes of 0.803 and 0.767 in the training and validation group respectively. Moreover, the calibration curves of both cohorts for the probability of survival showed good agreement between prediction by nomogram and actual observation in 1-, 3- and 5-year DSS. The ROC curves demonstrated the prediction accuracy of the established nomogram (all AUC>0.8). DCA confirmed the better potential clinical practicality of the nomogram in the prediction of LCNEC survival than AJCC staging. A risk classification system was built which could perfectly classify LCNEC patients into high- and low-risk groups(p<0.001). Subgroup analysis showed that WBRT did not bring survival benefits, PCI appeared to have survival benefits in LCNEC patients without brain metastases (p>0.05).

CONCLUSION

The prognostic nomogram developed in this study has certain prognostic value and clinical practicality for LCNEC patients. PCI might be investigated as a means of improving prognosis.

Prediction of progesterone receptor expression in high-grade meningioma by using radiomics based on enhanced T1WI

AIM

To predict progesterone receptor (PR) expression of high-grade meningioma using radiomics based on enhanced T1-weighted imaging (WI).

MATERIALS AND METHODS

There were 157 cases of high-grade meningioma in the study. Seventy-eight cases had negative expression and 79 cases had positive expression. Spearman's rank correlation coefficient and least absolute shrinkage and selection operator (LASSO) regression were used to select the valuable features. The models were developed by naive Bayes (NB), random forest (RF), and support vector machine (SVM). Receiver operating characteristic (ROC) and decision curve analysis (DCA) analysis were used to assess the models.

RESULTS

Nine features were selected as the valuable features using Spearman's analysis and LASSO regression. The RF and NB models achieved the same area under the ROC curve (AUC) of 0.75, which was higher than that of SVM (0.74). There was no significant difference among the AUCs of the three models (p>0.05). There was a larger net benefit in the RF model than the SVM and NB models across all threshold probabilities in the DCA analysis.

CONCLUSION

The RF model had good performance in predicting PR expression of high-grade meningioma. PR expression evaluation for high-grade meningioma would be helpful in clinical practice.

A dual-centre study on the radioprotective effect of a novel X-ray protection device during coronary intervention

AIM

To investigate the shielding efficiency of a novel X-ray protection device (NPD) compared with the traditional lead clothing (TLC) during coronary intervention.

MATERIALS AND METHODS

This study was performed prospectively in two centres. A total of 200 coronary interventions were included and assigned equally into the NPD or TLC group. The NPD is a floor-standing X-ray protection device, which mainly composes of a barrel-like frame and two layers of lead rubber. Thermoluminescent dosimeters (TLDs) were adopted to detect the cumulative absorbed doses, and were attached outside the NPD or TLC or body of the first operator at four different height levels in four directions during the procedure.

RESULTS

The cumulative doses outside the NPD were comparable to that of the TLC (2,398.33 ± 2,341.64 versus 1,624.09 ± 1,732.20 μSv, p=0.366), and the cumulative doses inside the NPD were significantly lower than those inside the TLC (40 ± 0 versus 732.28 ± 919.83 μSv, p<0.001). As the TLC did not cover the calf segment of the operator, the area at 50 cm height from the floor in the TLC group was unshielded. The shielding efficiency of NPD was significantly higher than that of the TLC (98.2 ± 0.63% versus 52.11 ± 38.97%, p=0.021).

CONCLUSION

The NPD has a significantly higher shielding efficacy than that of the TLC, in particular, it protects the operators' lower limb, liberates their lower body from wearing heavy lead apron, and may consequently reduce the radiation or body-load associated complications.

Real-Time 3D Liver Tumor Localization via Combined Optical Surface Imaging and an X-Ray Projection from Arbitrary Imaging Angles

PURPOSE/OBJECTIVE(S)

A deep learning (DL)-based, deformable registration-driven liver tumor localization technique was developed for onboard deformable motion tracking. The technique (Surf-X360-Bio) uses in-room optical surface imaging and an x-ray projection at an arbitrary scan angle to solve volumetric liver and liver tumor motion in real-time.

MATERIALS/METHODS

Surf-X360-Bio solves the volumetric motion of the liver and localizes the liver tumor, through deforming liver and liver tumor meshes segmented on prior 4D-CTs/CBCTs. It uses real-time onboard information from an optical surface image and a simultaneously-acquired x-ray projection (from an arbitrary scan angle). Surf-X360-Bio localizes tumors via two steps: liver boundary motion estimation and intra-liver motion derivation. Surf-X360-Bio first estimates liver boundary motion by a patient-specific surface imaging model (Surf), utilizing the correlation between the external body surface motion and the internal liver boundary motion. As the correlation can be imperfect, the residual motion estimation errors were corrected by a patient-specific, angle-agnostic x-ray imaging model (X360). X360 deformed the liver boundary to match motion-related imaging features encoded in an arbitrarily-angled x-ray projection, using the Surf output for initialization. X360 adopted a geometry-aware learning module to extract and adapt to angle-varying features of arbitrarily-angled x-ray images, by calculating the projection system matrix of each x-ray image on-the-fly during model training and inference. After the liver boundary motion estimation by Surf and X360, intra-liver deformation was solved by a biomechanical model (Bio) to propagate the liver boundary motion inside to localize the tumors. The DL-based Bio model used domain knowledge of tissue biomechanics and finite element analysis (FEA) to solve intra-liver motion, with a much faster speed than conventional FEA methods to meet the real-time constraint. Surf-X360-Bio was evaluated using a dataset of 34 liver patients. Liver tumor localization accuracy was evaluated by the Dice similarity coefficient (DSC), the 95-percentile Hausdorff distance (HD95), and the center-of-mass error (COME).

RESULTS

Using 3,306 motion scenarios spanning the 360 degree x-ray scan angles for each testing patient, Surf-X360-Bio localized the liver tumors to 0.81 (mean) ± 0.16 (s.d.) in DSC, 2.5 ± 1.7 mm in HD95, and 2.1 ± 1.8 mm in COME. In comparison, the prior reference image without deformable registration-driven localization yielded 0.42 ± 0.29 in DSC, 8.1 ± 5.2 mm in HD95, and 8.5 ± 5.2 mm in COME. Via Surf-X360-Bio, the overall inference time was below 230 ms for each case.

CONCLUSION

Combining optical surface imaging and x-ray imaging, Surf-X360-Bio achieved fast (<250 ms inference time), accurate (mean error < 2.1 mm), and robust liver tumor localizations at arbitrary x-ray scan angles for real-time, marker-less 3D deformable motion tracking.

Exploration of Multiomic Profiles and Biomarkers as Predictors of Neoadjuvant Chemoradiotherapy Responsiveness in Esophageal Squamous Cell Carcinoma

PURPOSE/OBJECTIVE(S)

The current gold standard of care for resectable locally advanced esophageal cancer is neoadjuvant chemoradiotherapy (NCRT) followed by surgery. Given that only 30-40% of patients with esophageal squamous cell carcinoma (ESCC) achieved a pathologic complete response (pCR) following neoadjuvant chemoradiotherapy, it is critical to understand the biological basis of NCRT resistance in esophageal cancer and identify biomarkers for these patients in order to further personalize treatment plans. We aim to depict the biological landscape of ESCC responsiveness and resistance to neoadjuvant chemoradiotherapy.

MATERIALS/METHODS

Endoscopic biopsied specimens of the primary tumors and paired peripheral blood samples were obtained from 24 patients before neoadjuvant chemoradiotherapy and tested for whole exosome sequencing, RNA sequencing, and DIA mass spectrometry. Genomic data were analyzed for significantly mutated genes, copy number alterations, MSI, TMB, and mutational signatures. Transcriptomics and proteomics data were used to examine differentially activated pathways. GSEA and ActivePathways were used for the single omics level and joint multi-omics analysis, respectively. Tumor microenvironment (TME) characteristics were deconvoluted by xCell upon RNA-seq data. Treatment resistance biomarkers were identified and validated in a separate cohort using mIHC.

RESULTS

In the study cohort, 54% (13/24) of the patients achieved pCR. WES data suggested that FBXW7 was more frequently mutated in the pCR group (fisher test p-value = 0.029), and the most significant cytoband loss in the pCR group was 9p21.3 (qval = 0.001). Differences in TMB, MSI, and mutational signatures were not significant between groups. Combined transcriptomics and proteomics analysis revealed that type I interferon signaling pathways and RIG-I-like receptor signaling pathways(p<0.05) were enriched in non-pCR tumors. Esophageal cancer cohort RNA-seq data from TCGA verified the correlation between the genetic variances (FBXW7 mutation and 9p21.3 loss) and the decreased expression of type I interferon signaling pathway genes. In TME analysis, tolerogenic dendritic cells and exhausted T cell signatures were significantly enriched in non-pCR tumors, indicating an immunosuppressive status in treatment resistant patients. Based on proteomics PPI network and differential expression genes from RNA-seq data, a biomarker panel consisted of 12 proteins predictive of non-pCR tumors was identified: STAT1, EIF2AK2, MX1, BST2, TRIM21, SAMHD1, IFI44L, GBP1, PARP14, ISG15, IFIT3, and HLA-B. The expression of selected genes was validated by mIHC in an independent cohort.

CONCLUSION

Through a multiomics approach, we described the biological characteristics of ESCC with distinct responses to neoadjuvant chemoradiotherapy and proposed a panel of 12 proteins as predictive biomarkers for non-pCR patients.

Ten-Year Outcomes of Hypofractionated (45 Gy in 9 Fractions) Intensity Modulated Radiotherapy for Localized Prostate Cancer

PURPOSE/OBJECTIVE(S)

We reported 10-year outcomes of localized prostate cancers treated with hypofractionated intensity-modulated radiotherapy of 45 Gy in 9 consecutive fractions.

MATERIALS/METHODS

From October 2011 to April 2017, thirty patients with localized prostate cancer were enrolled in this prospective trial. The median age of the patients was 72.5 years. According to NCCN recurrence risk criteria, eight patients were at low-risk group, 17 at intermediate risk group, 5 at high-risk group. All patients were treated with hypofractionated intensity-modulated radiotherapy (IMRT) of 45 Gy in 9 consecutive fractions to their prostate with or without seminal vesicles. Before radiotherapy, three gold fiducials were implanted into the prostate. In order to reduce the rectal high dose irradiation volume, an inflated rectal balloon was placed in the rectum at simulation and every treatment and patients were treated with comfortable full bladder. Static Intensity-modulated radiotherapy (SIMRT) was applied in 1 patient, Volumetric Modulated Arc Therapy (VMAT) in 27 patients, and tomotherapy in 2 patients. Image guided radiotherapy (IGRT) with gold fiducial registration was adopted. Twenty-six patients also received androgen deprivation therapy (ADT). The median time of ADT was 6 months. Progression⁃free survival (PFS) and overall survival (OS) were analyzed using Kaplan-Meier analysis. All grade ≥1 genitourinary (GU) and gastrointestinal (GI) toxicities were recorded using Common Terminology Criteria for Adverse Event version 5.0 (CTCAE 5.0) and Radiation Therapy Oncology Group (RTOG) late morbidity criteria, and GU and GI toxicities were cumulatively calculated.

RESULTS

After a median follow-up of 102 months (65∼131 months), the 10-year OS was 90.0% (95% confidence interval, 83.3%-96.7%), and the 10-year PFS was 86.5% (95% confidence interval, 79.1%-93.9%). According to CTCAE 5.0, grade 1 acute gastrointestinal (GI) toxicity developed in 12 patients, grade 2 in 2 patients, grade 3 in 2 patients, and grade 1 acute genitourinary (GU) toxicity developed in 12 patients, grade 2 in 2 patients, and no grade 3 or higher toxicity occurred. According to RTOG late morbidity criteria, late (≥3 months after radiotherapy) grade 1 GI toxicity developed in 4 patients (13.3%), grade 2 in 1 (3.3%), grade 3 in 1 (3.3%), and late grade 1 GU toxicity occurred in 1 patient (3.3%), grade 2 in 1 (3.3%), grade 3 in 1 (3.3%). No grade 4 or higher GI and GU toxicities developed. Only one grade 3 GI and one grade 2 GU toxicities were observed for the maximum toxicity at the last follow-up. The potency was not evaluated.

CONCLUSION

The 10-year oncologic outcomes of this shortened hypofractionated IMRT regimen for mainly low/intermediate risk prostate cancer patients is favorable with acceptable acute and late toxicities.

Value of Baseline Metabolic Tumor Volume for Survival Prognosis and Optimization of Risk-Adapted Treatment Therapy in Patients with Extranodal Nasal-Type Natural Killer/T-Cell Lymphoma

PURPOSE/OBJECTIVE(S)

To assess the association of baseline metabolic tumor volume (MTV) with overall survival (OS) and to explore its potential role in optimization of existing risk-adapted therapy in ENKTCL.

MATERIALS/METHODS

A total of 133 ENKTCL patients mainly treated by radiotherapy (RT) alone (33.8%) or RT combined with chemotherapy (combined-modality therapy [CMT]) (60.9%) were prospectively included. The impacts of MTV, SUVmax derived from 18F-FDG PET/CT image and clinical factors on OS were investigated. Survival analyses were conducted using Kaplan-Meier method with log-rank tests. Cox proportional hazards regression analysis was used to identify multivariate predictors of OS. Regression-based mediation analysis estimated the hazard ratio (HR) of death for direct effect (not through distant metastasis or locoregional recurrence) and indirect effect (through distant metastasis or locoregional recurrence) of the pathway MTV→distant metastasis→OS and pathway MTV→locoregional recurrence→OS. Inverse probability of treatment weighting (IPTW) analysis was employed to make covariate adjustments.

RESULTS

MTV and SUVmax were correlated with LDH, PTI, Ann Arbor stage, and NRI score. In univariable analysis, SUVmax, MTV, ECOG PS, PTI and Ann Arbor stage were statistically significantly prognostic factors for OS. Multivariate analysis showed that MTV was the only independent factor of short OS (HR 4.98, 95% CI (1.85 - 13.42), p = 0.002). Mediation analysis showed that distant metastasis played a complete mediating role in the increased death caused by higher MTV (HR of indirect effect 3.15, 95% CI (1.34 - 7.41), p = 0.009; HR of direct effect 2.88, 95% CI (0.80 - 10.32), p = 0.767), with proportion of mediation 76.7%, while locoregional recurrence was not a mediating factor (HR of indirect effect 1.16, 95% CI (0.90 - 1.48), p = 0.255; HR of direct effect 4.48, 95% CI (1.30 - 15.44), p = 0.017) . After adjusting the clinical factors by IPTW between RT alone group and CMT group in early intermediate and high risk ENKTCL, CMT had no PFS and OS benefits compared with RT alone in the low-MTV group (MTV < 49.6ml), while in the high-MTV group (MTV ≥ 49.6ml), the use of CMT compared with RT alone prolonged PFS and OS.

CONCLUSION

Baseline metabolic tumor volume is an independent prognostic factor for overall survival and distant metastasis rather than locoregional recurrence mediated increased risk of death in patients with MTV higher than 49.6ml. For early-stage intermediate and risk ENKTCL patients with MTV lower than 49.6ml, omission of chemotherapy may not result in loss of PFS and OS.

Radiotherapy Effect on Long-Term Net Survival Benefit for Early-Stage Diffuse Large B-Cell Lymphoma in the Rituximab Era

PURPOSE/OBJECTIVE(S)

It is controversial whether to add consolidative radiotherapy (RT) after chemoimmunotherapy in the first-line treatment for diffuse large B-cell lymphoma (DLBCL). This study aimed to investigate the long-term net survival benefit of RT for early-stage DLBCL in the rituximab era.

MATERIALS/METHODS

The data of 10,841 adult patients with early-stage DLBCL from the Surveillance, Epidemiology, and End Results (SEER) database between 2002 and 2015 were extracted and analyzed. The patients had received combined modality treatment (CMT, chemotherapy plus RT) or chemotherapy alone. Linear regression analysis was performed for RT utilization by year of diagnosis. Competing risk analysis was used to evaluate the cumulative incidence of mortality according to the cause of death. Inverse probability of treatment weighting (IPTW) was used to balance the distribution of covariates between treatment arms. Relative survival (RS), standardized mortality ratio (SMR), and transformed Cox regression were performed to estimate the net survival benefit of RT by controlling for background mortality.

RESULTS

Linear regression revealed that the slope of the best-fit line for RT utilization over time was negative between 2002 and 2015 (m = -0.006, P = 0.003). A total of 4,648 deaths were recorded among 10,841 patients; 55.6% were lymphoma-related death (LRD), and 44.4% were attributed to other causes. Patients initially treated with CMT had a lower cumulative incidence of LRD than chemotherapy alone (HR 0.63, 95% CI: 0.57-0.69; P < 0.001). The 10-year overall survival (OS) rate of 66.1%, RS rate of 85.0%, and SMR of 1.71 achieved with CMT were significantly better than chemotherapy alone (OS, 53.0%; RS, 69.8%; SMR, 2.62; P < 0.001). By IPTW and multivariable analysis, the addition of RT remained associated with better OS (HR 0.67, 95% CI: 0.62-0.71; P < 0.001) and RS (HR 0.69, 95% CI: 0.65-0.74; P < 0.001).

CONCLUSION

RT was associated with better long-term net survival in patients with early-stage DLBCL in the rituximab era.

Retrospective study of preservation and transection of the round ligament of uterus during laparoscopic transabdominal preperitoneal inguinal hernia repair in adult women

PURPOSE

The processing of the round ligament of uterus in laparoscopic transabdominal preperitoneal (TAPP) repair of inguinal hernia in women has contended. This study aimed to explore whether there is any difference in the surgical outcome and postoperative complications between the two processing modalities, preservation, and transection of the round ligament of uterus, in adult female inguinal hernia patients undergoing TAPP.

METHODS

Retrospective analysis of 84 female patients (117 sides) who underwent TAPP in XXX Hospital from July 2013 to August 2022. Patient characteristics and technical details of the surgical procedure were collected and divided into two groups according to whether the round ligament of uterus was severed intraoperatively or not. There were 52 cases (77 sides) in the group with preservation of the round ligament of uterus and 32 cases (40 sides) in the group with transection of the round ligament of uterus, comparing the general condition, surgical condition, and the occurrence of postoperative related complications between the 2 groups.

RESULTS

The operative time for unilateral primary inguinal hernia was (129.2 ± 35.1) and (89.5 ± 42.6) minutes in the preservation and transection groups, respectively. There were no statistical differences between the two groups in terms of age, length of hospital stay, ASA, BMI, history of lower abdominal surgery, type and side of hernia, intraoperative bleeding, and time to surgery for primary bilateral hernia (P > 0.05). In addition, there was likewise no statistical difference in the occurrence of postoperative Clavien-Dindo classification, VAS, seroma, mesh infection, labia majora edema, chronic pain or abnormal sensation in the inguinal region, and hernia recurrence in the two groups as well (P > 0.05).

CONCLUSION

There is no evidence that the transection of the round ligament of the uterus during TAPP has an impact on postoperative complications in patients. However, given the important role of the uterine round ligament in the surgical management of patients with uterine prolapse and the high incidence of uterine prolapse in older women, hernia surgeons should also be aware of the need to protect the round ligament of uterus in older women.

Physiomimetic biocompatibility evaluation of directly printed degradable porous iron implants using various cell types

Additively manufactured (AM) degradable porous metallic biomaterials offer unique opportunities for satisfying the design requirements of an ideal bone substitute. Among the currently available biodegradable metals, iron has the highest elastic modulus, meaning that it would benefit the most from porous design. Given the successful preclinical applications of such biomaterials for the treatment of cardiovascular diseases, the moderate compatibility of AM porous iron with osteoblast-like cells, reported in earlier studies, has been surprising. This may be because, as opposed to static in vitro conditions, the biodegradation products of iron in vivo are transported away and excreted. To better mimic the in situ situations of biodegradable biomaterials after implantation, we compared the biodegradation behavior and cytocompatibility of AM porous iron under static conditions to the conditions with dynamic in situ-like fluid flow perfusion in a bioreactor. Furthermore, the compatibility of these scaffolds with four different cell types was evaluated to better understand the implications of these implants for the complex process of natural wound healing. These included endothelial cells, L929 fibroblasts, RAW264.7 macrophage-like cells, and osteoblastic MG-63 cells. The biodegradation rate of the scaffolds was significantly increased in the perfusion bioreactor as compared to static immersion. Under either condition, the compatibility with L929 cells was the best. Moreover, the compatibility with all the cell types was much enhanced under physiomimetic dynamic flow conditions as compared to static biodegradation. Our study highlights the importance of physiomimetic culture conditions and cell type selection when evaluating the cytocompatibility of degradable biomaterials in vitro. STATEMENT OF SIGNIFICANCE: Additively manufactured (AM) degradable porous metals offer unique opportunities for the treatment of large bony defects. Despite the successful preclinical applications of biodegradable iron in the cardiovascular field, the moderate compatibility of AM porous iron with osteoblast-like cells was reported. To better mimic the in vivo condition, we compared the biodegradation behavior and cytocompatibility of AM porous iron under static condition to dynamic perfusion. Furthermore, the compatibility of these scaffolds with various cell types was evaluated to better simulate the process of natural wound healing. Our study suggests that AM porous iron holds great promise for orthopedic applications, while also highlighting the importance of physio-mimetic culture conditions and cell type selection when evaluating the cytocompatibility of degradable biomaterials in vitro.

Observation of New Ω_{c}^{0} States Decaying to the Ξ_{c}^{+}K^{-} Final State

Two new excited states, Ω_{c}(3185)^{0} and Ω_{c}(3327)^{0}, are observed in the Ξ_{c}^{+}K^{-} invariant-mass spectrum using proton-proton collision data collected by the LHCb experiment, corresponding to an integrated luminosity of 9  fb^{-1}. Five previously observed excited Ω_{c}^{0} states are confirmed, namely Ω_{c}(3000)^{0}, Ω_{c}(3050)^{0}, Ω_{c}(3065)^{0}, Ω_{c}(3090)^{0}, and Ω_{c}(3119)^{0}. The masses and widths of these seven states are measured with the highest precision to date.

Evidence of a J/ψK_{S}^{0} Structure in B^{0}→J/ψϕK_{S}^{0} Decays

An amplitude analysis of B^{0}→J/ψϕK_{S}^{0} decays is performed using proton-proton collision data, corresponding to an integrated luminosity of 9  fb^{-1}, collected with the LHCb detector at center-of-mass energies of 7, 8, and 13 TeV. Evidence with a significance of 4.0 standard deviations of a structure in the J/ψK_{S}^{0} system, named T_{ψs1}^{θ}(4000)^{0}, is seen, with its mass and width measured to be 3991_{-10}^{+12} _{-17}^{+9}  MeV/c^{2} and 105_{-25}^{+29} _{-23}^{+17}  MeV, respectively, where the first uncertainty is statistical and the second systematic. The T_{ψs1}^{θ}(4000)^{0} state is likely to be the isospin partner of the T_{ψs1}^{θ}(4000)^{+} state, previously observed in the J/ψK^{+} system of the B^{+}→J/ψϕK^{+} decay. When isospin symmetry for the charged and neutral T_{ψs1}^{θ}(4000) states is assumed, the signal significance increases to 5.4 standard deviations.

Host response of Nicotiana benthamiana to the parasitism of five populations of root-lesion nematode, Pratylenchus coffeae, from China

In a recent survey of nematodes associated with tobacco in Shandong, China, the root-lesion nematode Pratylenchus coffeae was identified using a combination of morphology and molecular techniques. This nematode species is a serious parasite that damages a variety of plant species. The model plant benthi, Nicotiana benthamiana, is frequently used to study plant-disease interactions. However, it is not known whether this plant species is a host of P. coffeae. The objectives of this study were to evaluate the parasitism and pathogenicity of five populations of the root-lesion nematode P. coffeae on N. benthamiana.N. benthamiana seedlings with the same growth status were chosen and inoculated with 1,000 nematodes per pot. At 60 days after inoculation, the reproductive factors (Rf = final population densities (Pf)/initial population densities (Pi)) for P. coffeae in the rhizosphere of N. benthamiana were all more than 1, suggesting that N. benthamiana was a good host plant for P. coffeae.Nicotiana. benthamiana infected by P. coffeae showed weak growth, decreased tillering, high root reduction, and noticeable brown spots on the roots. Thus, we determined that the model plant N. benthamiana can be used to study plant-P. coffeae interactions.

Aggregation-Induced Asymmetric Charge States of Amino Acids in Supramolecular Nanofibers

Electrostatic interactions contribute critically to the kinetic pathways and thermodynamic outcomes of peptide self-assembly involving one or more than one charged amino acids. While it is well understood in protein folding that those amino acids with acidic/basic side chains could shift their pKas when placed in a hydrophobic microenvironment, to what extent aggregation of monomeric peptide units from the bulk solution could alter their charged status and how this change in pKa values would reciprocally impact their assembly outcomes. Here, we design and analyze two solution systems containing peptide amphiphiles with hydrocarbon chains of different lengths to determine the factor of deprotonation on assembly. Our results suggest that models of supramolecular nanofibers with uniformly distributed, fully charged amino acids are oversimplified. We demonstrate, with molecular dynamics simulations, and validate with experimental results that asymmetric, different protonation states of the peptides lead to distinct nanostructures after self-assembly. The results give estimates on the electrostatic interactions in peptide amphiphiles required for their self-assembly and shed light on modeling molecular assembly systems containing charged amino acids.

Cellulose nanofibers (CNFs) in the recycling of nickel and cadmium battery metals using electrodeposition

Cellulose nanofibers (CNFs) were employed in the aqueous electrodeposition of nickel and cadmium for battery metal recycling. The electrowinning of mixed Ni-Cd metal ion recycling solutions demonstrated that cadmium with a purity of over 99% could be selectively extracted while leaving the nickel in the solution. Two types of CNFs were evaluated: negatively charged CNFs (a-CNF) obtained through acid hydrolysis (-75 μeq. g-1) and positively charged CNFs (q-CNF) functionalized with quaternary ammonium groups (+85 μeq. g-1). The inclusion of CNFs in the Ni-Cd electrolytes induced growth of cm-sized dendrites in conditions where dendrites were otherwise not observed, or increased the degree of dendritic growth when it was already present to a lesser extent. The augmented dendritic growth correlated with an increase in deposition yields of up to 30%. Additionally, it facilitated the formation of easily detachable dendritic structures, enabling more efficient processing on a large scale and enhancing the recovery of the toxic cadmium metal. Regardless of the charged nature of the CNFs, both negatively and positively charged CNFs led to a significant formation of protruding cadmium dendrites. When deposited separately, dendritic growth and increased deposition yields remained consistent for the cadmium metal. However, dendrites were not observed during the deposition of nickel; instead, uniformly deposited layers were formed, albeit at lower yields (20%), when positively charged CNFs were present. This paper explores the potential of utilizing cellulose and its derivatives as the world's largest biomass resource to enhance battery metal recycling processes.

[The first imported case of visceral leishmaniasis in Shenzhen City]

A patient with fever, chills, and pancytopenia as major clinical manifestations was presented. To investigate the cause, the patient's peripheral blood was collected for pathogen screening using metagenomic next - generation sequencing (mNGS). The DNA sequence of Leishmania donovani was detected, and Leishmania amastigotes were found in bone marrow smears using microscopy. The case was therefore definitively diagnosed as visceral leishmaniasis, and was cured and discharged from hospital following treatment with liposomal amphotericin B for 14 days. This is the first imported case of visceral leishmaniasis since the founding of Shenzhen City in 1979.

[Investigation and factor analysis of postoperative surgical site infections in emergency abdominal surgery in China from 2018 to 2021 based on Chinese SSI Surveillance]

Objective: We investigated the incidence of surgical site infection (SSI) following emergency abdominal surgery (EAS) in China and further explored its risk factors, providing a reference for preventing and controlling SSI after EAS. Methods: This was an observational study. Data of patients who had undergone EAS and been enrolled in the Chinese SSI Surveillance Program during 2018-2021were retrospectively analyzed. All included patients had been followed up for 30 days after surgery. The analyzed data consisted of relevant patient characteristics and perioperative clinical data, including preoperative hemoglobin, albumin, and blood glucose concentrations, American Society of Anesthesiologists (ASA) score, grade of surgical incision, intestinal preparation, skin preparation, location of surgical site, approach, and duration. The primary outcome was the incidence of SSI occurring within 30 days following EAS. SSI was defined as both superficial and deep incisional infections and organ/space infections, diagnoses being supported by results of microbiological culture of secretions and pus. Secondary outcomes included 30-day postoperative mortality rates, length of stay in the intensive care unit (ICU), duration of postoperative hospitalization, and associated costs. The patients were classified into two groups, SSI and non-SSI, based on whether an infection had been diagnosed. Univariate and multivariate logistic regression analyses were performed to identify risk factors associated with SSI following EAS. Results: The study cohort comprised 5491 patients who had undergone EAS, comprising 3169 male and 2322 female patients. SSIs were diagnosed in 168 (3.1%) patients after EAS (SSI group); thus, the non-SSI group consisted of 5323 patients. The SSIs comprised superficial incision infections in 69 (41.1%), deep incision infections in 51 (30.4%), and organ or space infections in 48 (28.6%). Cultures of secretions and pus were positive in 115 (68.5%) cases. The most frequently detected organism was Escherichia coli (47/115; 40.9%). There were no significant differences in sex or body mass index between the SSI and non-SSI groups (both P>0.05). However, the proportion of individuals aged 60 years or older was significantly greater in the SSI than in the non-SSI group (49.4% [83/168] vs. 27.5% [1464/5323), χ2=38.604, P<0.001). Compared with the non-SSI group, the SSI group had greater proportions of patients with diabetes (11.9% [20/168] vs. 4.8% [258/5323], χ2=16.878, P<0.001), hypertension (25.6% [43/168] vs. 12.2% [649/5323], χ2=26.562, P<0.001); hemoglobin <110 g/L (27.4% [46/168] vs. 13.1% [697/5323], χ2=28.411, P<0.001), and albuminemia <30 g/L (24.4% [41/168] vs. 5.9% [316/5323], χ2=91.352, P<0.001), and a reduced rate of preoperative skin preparation (66.7% [112/168] vs. 75.9% [4039/5323], χ2=7.491, P=0.006). Furthermore, fewer patients in the SSI group had preoperative ASA scores of between one and two (56.0% [94/168] vs. 88.7% [4724/5323], χ2=162.869, P<0.001) in the non-SSI group. The incidences of contaminated and infected incisions were greater in the SSI group (63.1% [106/168] vs. 38.6% [2056/5323], χ2=40.854, P<0.001). There was a significant difference in surgical site distribution between the SSI and non-SSI groups (small intestine 29.8% [50/168] vs. 10.6% [565/5323], colorectal 26.2% [44/168] vs. 5.6% [298/5 323], and appendix 24.4% [41/168] vs. 65.1% [3465/5323]) χ2=167.897, P<0.001), respectively. There was a significantly lower proportion of laparoscope or robotic surgery in the non-SSI group (24.4 % [41/168] vs. 74.2% [3949/5323], χ2=203.199, P<0.001); the percentage of operations of duration less than 2 hours was significantly lower in the SSI than non-SSI group (35.7% [60/168] vs. 77.4% [4119/5323], χ2=155.487, P<0.001). As to clinical outcomes, there was a higher 30-day postoperative mortality rate (3.0%[5/168] vs. 0.2%[10/5323], χ2=36.807, P<0.001) and higher postoperative ICU occupancy rate (41.7% [70/168] vs. 19.7% [1046/5323], χ2=48.748, P<0.001) in the SSI group. The median length of stay in the ICU (0[2] vs. 0[0] days, U=328597.000, P<0.001), median total length of stay after surgery (16[13] vs. 6[5] days, U=128146.000, P<0.001), and median hospitalization cost (ten thousand yuan, 4.7[4.4] vs. 1.7[1.8], U=175965.000, P<0.001) were all significantly greater in the SSI group. Multivariate logistic regression analysis revealed that the absence of skin preparation before surgery (OR=2.435,95%CI: 1.690-3.508, P<0.001), preoperative albuminemia <30 g/L (OR=1.680, 95%CI: 1.081-2.610, P=0.021), contaminated or infected incisions (OR=3.031, 95%CI: 2.151-4.271, P<0.001), and laparotomy (OR=3.436, 95% CI: 2.123-5.564, P<0.001) were independent risk factors of SSI. Operative duration less than 2 hours (OR=0.465, 95%CI: 0.312-0.695, P<0.001) and ASA score of 1-2 (OR=0.416, 95% CI: 0.289-0.601, P<0.001) were identified as independent protective factors for SSI. Conclusions: It is important to consider the nutritional status in the perioperative period of patients undergoing EAS. Preoperative skin preparation should be conducted and, whenever possible, laparoscope or robot-assisted surgery. Duration of surgery should be as short as possible while maintaining surgery quality and improving patient care.

[Construction of a schistosomiasis transmission risk assessment system in Wuhan City based on analytic hierarchy process]

OBJECTIVE

To construct a schistosomiasis transmission risk assessment system in Wuhan City and preliminary evaluate its application effect, so as to promote the rational allocation of schistosomiasis control resources and accelerate the progress towards schistosomiasis elimination.

METHODS

The schistosomiasis risk assessment indicators were collected through referring schistosomiasis surveillance data of Wuhan City from 2014 to 2020, literature review and expert interviews. Indicators within each criterion and sub-criterion were screened using the Delphi method, and a hierarchical structure model was created based on analytic hierarchy process. Quantitative assignment of each indicator was conducted according to relative importance, and the weight and combination weight of each criterion were calculated in each analytic hierarchy framework to create a schistosomiasis transmission risk assessment system, which was used for the schistosomiasis transmission risk assessment in 12 national schistosomiasis surveillance sites in Wuhan City.

RESULTS

A three-level schistosomiasis transmission risk assessment system was preliminarily constructed, which included a target layer, 5 criterion layers and 21 sub-criterion layers. Of all indicators in the criterion layer, transmission route had the highest weight (0.433), followed by source of Schistosoma japonicum infection (0.294); and among all indicators in the sub-criterion layer, S. japonicum infection in Oncomelania hupensis and sentinel mice had the highest combination weight (0.125), followed by prevalence of S. japonicum infection in humans (0.091) and bovines (0.053), snail control by chemical treatment (0.049), positive rate of inquiry examinations (0.048), allocation of schistosomiasis control professionals (0.045), and areas of submerged snail-infested settings (0.041). Of the 12 national schistosomiasis surveillance sites in Wuhan City, there were 5 sites with weights of > 0.8, 4 sites with weights of 0.6 to 0.8, and 3 sites with weights of < 0.6 in 2020.

CONCLUSIONS

A schistosomiasis transmission risk assessment system has been constructed based on analytic hierarchy process in Wuhan City, which may provide a evidence-based basis for health resource allocation and decision-making for schistosomiasis control.

[The predictive value of melanin-concentrating hormone combined with other related biomarkers in cerebrospinal fluid in preoperative cognitive dysfunction of elderly patients]

Objective: To explore the predictive value of cerebrospinal fluid melanin-concentrating hormone (MCH) combined with other related biomarkers in preoperative cognitive dysfunction of elderly patients. Methods: A total of 80 patients who underwent elective hip or knee replacement under intravertebral anesthesia in Chifeng Municipal Hospital, Inner Mongolia, from March to November 2022 were prospectively included, with 32 males and 48 females, and aged 65-85 (70.7±5.2) years old. According to the evaluation results of the Montreal Cognitive Assessment (MoCA), patients were divided into the preoperative cognitive dysfunction (n=23) and control (n=57) groups. The levels of MCH, amyloid-β 40 (Aβ40), amyloid-β 42 (Aβ42), and phosphorylated tau protein (p-tau) in cerebrospinal fluid were determined by enzyme-linked immunosorbent assay (ELISA). The receiver operating characteristic (ROC) curve was drawn to evaluate the predictive value of each biomarker separately or in combination for preoperative cognitive dysfunction. Spearman's rank correlation analysis was utilized to test the correlation between the level of each biomarker and MoCA scores. Results: The levels of MCH, Aβ40, Aβ42, p-tau, and Aβ42/p-tau in the preoperative cognitive dysfunction group were (35.53±5.94) μg/L, (39.21±9.18) ng/L, (221.83±43.17) ng/L, (42.64±9.74) ng/L, and 5.53±1.92, and the levels of these biomarkers in the control group were (28.74±4.90) μg/L, (36.37±7.87) ng/L, (280.23±45.67) ng/L, (35.00±9.27) ng/L, and 8.62±2.78, respectively. Compared with the control group, the levels of cerebrospinal fluid MCH and p-tau in the preoperative cognitive dysfunction group were significantly increased (all P<0.01), and the levels of Aβ42 and Aβ42/p-tau were significantly decreased (all P<0.001). MCH and Aβ42/p-tau provided higher predictive values. The area under the curve (AUC) of MCH and Aβ42/p-tau were 0.807 (95%CI: 0.703-0.911) and 0.842 (95%CI: 0.741-0.943), the sensitivity were 78.3% and 87.0%, and the specificity were 75.4% and 94.7%. MCH combined with Aβ42/p-tau have the higher AUC of 0.915 (95%CI: 0.837-0.992), the sensitivity (87.0%) and specificity (86.0%) were both high, which had a higher predictive value. The levels of cerebrospinal fluid MCH and p-tau were negatively correlated with MoCA score (r=-0.467, -0.321, all P<0.01), and the levels of Aβ42 and Aβ42/p-tau were positively correlated with MoCA score (r=0.480, 0.520, all P<0.001). Conclusion: The increase in cerebrospinal fluid MCH levels is associated with preoperative cognitive dysfunction in elderly patients. MCH combined with Aβ42/p-tau has the greatest predictive value.

Measurement of the Ratios of Branching Fractions R(D^{*}) and R(D^{0})

The ratios of branching fractions R(D^{*})≡B(B[over ¯]→D^{*}τ^{-}ν[over ¯]_{τ})/B(B[over ¯]→D^{*}μ^{-}ν[over ¯]_{μ}) and R(D^{0})≡B(B^{-}→D^{0}τ^{-}ν[over ¯]_{τ})/B(B^{-}→D^{0}μ^{-}ν[over ¯]_{μ}) are measured, assuming isospin symmetry, using a sample of proton-proton collision data corresponding to 3.0  fb^{-1} of integrated luminosity recorded by the LHCb experiment during 2011 and 2012. The tau lepton is identified in the decay mode τ^{-}→μ^{-}ν_{τ}ν[over ¯]_{μ}. The measured values are R(D^{*})=0.281±0.018±0.024 and R(D^{0})=0.441±0.060±0.066, where the first uncertainty is statistical and the second is systematic. The correlation between these measurements is ρ=-0.43. The results are consistent with the current average of these quantities and are at a combined 1.9 standard deviations from the predictions based on lepton flavor universality in the standard model.

[Genetic analysis of a family with hereditary hemorrhagic telangiectasia caused by endoglin gene mutation]

Objective: To explore the genetic characteristics of a family with hereditary hemorrhagic telangiectasia (HHT) caused by endoglin (ENG) gene mutations. Methods: A total of 17 individuals from a 3-generation HHT family attending the First Affiliated Hospital of Dali University were selected as the research subjects. Clinical data and familial disease status of the HHT family proband were collected. Whole exome sequencing technology was used to screen for suspected pathogenic genes in the proband, and Sanger sequencing was used for family validation. Results: The proband and her mother had recurrent epistaxis and skin mucosal telangiectasia, and enhanced CT scans of the chest of the proband and her mother, daughter, and cousin indicated the presence of varying degrees of pulmonary arteriovenous malformations. The results of the full exon sequencing results showed that the proband carried the ENG gene c.579_599del non-shift deletion mutation, and Sanger sequencing showed that the mother, daughter, and cousin carried the same mutation. Conclusion: ENG gene c.579_ 599del mutation may be the genetic basis of HHT in this family.

[A clinical observational study on the preliminary effect of dupilumab in the treatment of severe asthma]

Objective: To investigate the effect and safety of dupilumab in the treatment of patients with severe asthma in a preliminary clinical observational study. Methods: This study retrospectively analyzed the clinical data of 20 patients with severe asthma who received dupilumab for 4-12 months between 2019 and 2022 at the First Hospital of Guangzhou Medical University, comparing pre-and post-treatment laboratory data, oral glucocorticoid dose (OCS), asthma control test (ACT) and adverse effects. The median age of the 20 patients was 48.5 (41.0-52.8) years, including 14 males and 6 females. The clinical data of 10 patients treated with other biologic agents were further analyzed to determine the reasons for switching to biologic drug treatment and the efficacy of dupilumab in these patients. Paired t-tests or Wilcoxon signed-rank tests were used for comparisons. Mann-Whitney analysis was used for inter-group comparison, and chi-square test or Fisher test was used for inter-group comparisons of count data. Results: A total of 20 patients were included in this study. All 20 severe asthma phenotypes were type 2 (T2)-high and completed at least the first 4 months of treatment, including 17 patients who completed 12 months of treatment. Among patients who completed 4 months of treatment, the asthma exacerbation score decreased from 1.0(0.3-1.0) episodes/4 months to 0.0(0.0-1.0) episodes/4 months, P<0.001, and FEV1/FVC increased from 58.4% (50.5%-69.0%) to 66.9% (59.6%-77.7%), P<0.01. The number of patients requiring OCS maintenance therapy decreased from 15 (75%) to 9 (45%), P<0.05. Among patients who completed 12 months of treatment, the asthma exacerbation score decreased from 1.0(0.5-1.0) episodes/4 months to 0.0 (0.0-0.0) episodes/4 months, P<0.01, and FEV1/FVC increased from 57.9% (49.6%-67.8%) to 72.7% (64.6%-78.7%), P<0.01. The number of patients requiring OCS maintenance therapy decreased from 13 (76%) to 6 (35%), P<0.01. In 10 patients with a history of previous biologic therapy, the most common reasons for switching to a biologic were a poor response to previous monoclonal antibodies (40%) and loss of control of asthma symptom control after discontinuation of monoclonal antibodies (30%). The remaining reasons were patients' uncontrolled symptoms of chronic rhinosinusitis (20%) and irregular or underdosed use of previous biologics (10%). After 4 months of switching to dupilumab, 10 patients experienced varying degrees of improvement in asthma control. Conclusions: The application of dupilumab for the treatment of T2-high severe asthma showed good efficacy and few adverse effects. Biologically targeted therapy is an important treatment approach to achieving better control of severe asthma.

[Etiological analysis on a foodborne disease outbreak caused by two serotypes of Salmonella]

Objective: To understand the etiological characteristics of 2 serotypes of Salmonella strains isolated from a foodborne disease outbreak. Methods: A total of 11 anal swabs of the cases, 13 suspected contaminated food and 10 environmental samples were collected from a foodborne disease outbreak occurred on September 8, 2022 in a school. The anal swabs were enriched with selenite brilliant green enrichment broth (SBG) and brain heart infusion broth (BHI) respectively. PCR detection and culture of common intestinal pathogens were carried out. The suspected food samples were tested according to national standards for food safety. Multiple suspected Salmonella colonies were obtained and selected for serotype determination and whole genome sequencing. Serotypes were determined based on the whole-genome sequence, and clustering analysis was performed based on core genome single nucleotide polymorphism (SNP). Results: The positive rates of Salmonella in anal swabs and suspected food samples were 9/11 and 5/13 respectively. Both Salmonella Uganda and Salmonella Idikan were isolated from 4 anal swabs and 4 suspected food samples. For the remaining samples, only Salmonella Uganda or Salmonella Idikan was isolated in each sample. The positive rate of Salmonella in 11 anal swabs of the cases after BHI enrichment for 12 h and 24 h were all 9/11 in real-time PCR, same to the culture results. Salmonella Uganda and Salmonella Idikan formed two independent and genetically distant lineages in the clustering tree based on core genome SNP, and 0-14 and 0-23 SNP were observed in Salmonella Uganda and Salmonella Idikan respectively. Conclusions: This foodborne disease outbreak was probably caused by Salmonella Uganda and Salmonella Idikan, which both exhibited strong genetic diversity. The PCR based pathogen screening strategy plus pathogen enrichment for cases' annal swabs can be used in the routine outbreak investigation.

First Double-Differential Measurement of Kinematic Imbalance in Neutrino Interactions with the MicroBooNE Detector

We report the first measurement of flux-integrated double-differential quasielasticlike neutrino-argon cross sections, which have been made using the Booster Neutrino Beam and the MicroBooNE detector at Fermi National Accelerator Laboratory. The data are presented as a function of kinematic imbalance variables which are sensitive to nuclear ground-state distributions and hadronic reinteraction processes. We find that the measured cross sections in different phase-space regions are sensitive to different nuclear effects. Therefore, they enable the impact of specific nuclear effects on the neutrino-nucleus interaction to be isolated more completely than was possible using previous single-differential cross section measurements. Our results provide precision data to help test and improve neutrino-nucleus interaction models. They further support ongoing neutrino-oscillation studies by establishing phase-space regions where precise reaction modeling has already been achieved.

Measurement of the Prompt D^{0} Nuclear Modification Factor in p-Pb Collisions at sqrt[s_{NN}]=8.16 TeV

The production of prompt D^{0} mesons in proton-lead collisions in both the forward and backward rapidity regions at a center-of-mass energy per nucleon pair of sqrt[s_{NN}]=8.16  TeV is measured by the LHCb experiment. The nuclear modification factor of prompt D^{0} mesons is determined as a function of the transverse momentum p_{T}, and the rapidity in the nucleon-nucleon center-of-mass frame y^{*}. In the forward rapidity region, significantly suppressed production with respect to pp collisions is measured, which provides significant constraints on models of nuclear parton distributions and hadron production down to the very low Bjorken-x region of ∼10^{-5}. In the backward rapidity region, a suppression with a significance of 2.0-3.8 standard deviations compared to parton distribution functions in a nuclear environment expectations is found in the kinematic region of p_{T}>6  GeV/c and -3.25 Collapse

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[A randomized controlled study on the long-term efficacy of intra-cervical lymphatic immunotherapy for adult allergic rhinitis]

Objective: To determine the long-term efficacy and safety of intra-cervical lymphatic immunotherapy (ICLIT) for adult allergic rhinitis (AR) by comparing it with subcutaneous immunotherapy (SCIT). Methods: A total of 100 adult AR patients with dust mite allergy in Department of Otorhinolaryngology, First People's Hospital of Foshan from Feb 2018 to Dec 2019 were randomly divided into two groups, 50 in SCIT group [including 42 males and 8 females, aging (32.55±9.72) years] and 50 in ICLIT group [including 45 males and 5 females, aging (31.33±9.84) years]. The changes in total symptom score (total system score, TSS), nasal symptom score (total nasal symptom score, TNSS), eye symptom score (total ocular scoring system, TOSS), drug score (total medication score, TMS), and quality of life score of the two groups of patients were evaluated before and after treatment, and the adverse reactions of all patients during the treatment period were recorded. The changes in the level of dust mite specific IgE (sIgE) in the serum were evaluated. GraphPad Prism 9.0 software was used for statistical analysis. Results: In the SCIT group, 38 patients completed treatment and follow-up, with a dropout rate of 24%. In the ICLIT group, 48 patients completed treatment and follow-up, with a dropout rate of only 4%. The scores of TSS, TNSS, TOSS, TMS, and quality of life in the ICLIT group before treatment were 32.1±3.0, 27.3±3.1, 4.8±2.8, 2.3±0.9, and 68.1±28.7, respectively; After 36 months of treatment, the scores were 21.8±11.4, 18.1±9.4, 3.7±2.9, 1.3±1.1, and 36.0±26.7, respectively, which were significantly lower than those before treatment (all P<0.001). After 36 months of treatment, the TSS of the ICLIT group improved by 10.3±11.2 compared to before, while the TSS of the SCIT group improved significantly by 21.9±11.0 compared to before, with statistically significant differences between the groups (P<0.001). No serious systemic adverse reactions occurred in both groups of patients. Conclusions: ICLIT treatment for adult AR has long-term efficacy, high safety, and high compliance, but its long-term efficacy is not as good as SCIT. ICLIT can be considered as a new complementary option for AR immunotherapy.

Relationship between dietary patterns and diabetic microvascular complications in patients with type 2 diabetes mellitus

OBJECTIVE

This study aimed to investigate the relationship between different dietary patterns and diabetic microvascular complications in patients with type 2 diabetes mellitus.

PATIENTS AND METHODS

This study was conducted based on the Chinese Chronic Disease and its Risk Factor Surveillance System. A multi-stage stratified sampling method was used to randomly select two districts (Henghualing District, Taiyuan City, and Yuzi District, Jinzhong City) and two counties (Huguan County, Changzhi City, and Jiang County, Yuncheng City) from the chronic disease surveillance sites in Shanxi Province to collect general information, dietary records, physical measurements, and laboratory tests. In total, 1,227 patients were enrolled according to the study criteria. Factor analysis was performed to construct six dietary patterns, and the relationship between dietary pattern scores and type 2 diabetic microvascular complications was analysed using binary logistic regression after correcting for confounders.

RESULTS

(1) Regarding the prevalence of type 2 diabetic microvascular complications and dietary characteristics, the prevalence of microvascular complications in patients with type 2 diabetes mellitus was 55.3% and was higher in urban than in rural areas. The prevalence of diabetic kidney disease (DKD), diabetic retinopathy, and diabetic peripheral neuropathy (DPN) were 21.4%, 12.7%, and 38.0%, respectively. (2) Six dietary patterns were constructed, namely, 'animal protein', 'coarse grains and plant protein', 'nuts and fruits', 'refined grains and vegetables', 'dairy', and 'added sugars', with factor contributions of 15.42%, 9.99%, 8.23%, 8.16%, 7.56%, and 7.28% respectively, explaining 56.64% of the total dietary variation. (3) After adjusting for confounding variables, the results of binary logistic regression indicated that patients in the highest quartile of dietary pattern scores for 'nuts and fruits' experienced a 43.3% lower risk of DKD compared to those in the lowest quartile [odds ratio (OR) = 0.567; 95% confidence interval (CI), 0.359-0.894; p < 0.001]. Similarly, patients in the highest quartile of dietary pattern scores for 'animal protein' had a 42.8% lower risk of DPN compared with those in the lowest quartile (OR = 0.572; 95% CI, 0.388-0.843; p < 0.05).

CONCLUSIONS

The results of this study suggest that in patients with type 2 diabetes mellitus, a 'nuts and fruits' dietary pattern reduces the risk of DKD and an 'animal protein' dietary pattern reduces the risk of DPN.

Measurement of the Time-Integrated CP Asymmetry in D^{0}→K^{-}K^{+} Decays

The time-integrated CP asymmetry in the Cabibbo-suppressed decay D^{0}→K^{-}K^{+} is measured using proton-proton collision data, corresponding to an integrated luminosity of 5.7  fb^{-1} collected at a center-of-mass energy of 13 TeV with the LHCb detector. The D^{0} mesons are required to originate from promptly produced D^{*+}→D^{0}π^{+} decays, and the charge of the companion pion is used to determine the flavor of the charm meson at production. The time-integrated CP asymmetry is measured to be A_{CP}(K^{-}K^{+})=[6.8±5.4±1.6]×10^{-4} where the first uncertainty is statistical and the second systematic. The direct CP asymmetries in D^{0}→K^{-}K^{+} and D^{0}→π^{-}π^{+} decays, a_{K^{-}K^{+}}^{d} and a_{π^{-}π^{+}}^{d}, are derived by combining A_{CP}(K^{-}K^{+}) with the time-integrated CP asymmetry difference, ΔA_{CP}=A_{CP}(K^{-}K^{+})-A_{CP}(π^{-}π^{+}), and other inputs, giving a_{K^{-}K^{+}}^{d}=(7.7±5.7)×10^{-4},a_{π^{-}π^{+}}^{d}=(23.2±6.1)×10^{-4},with a correlation coefficient corresponding to ρ=0.88. The compatibility of these results with CP symmetry is 1.4 and 3.8 standard deviations for D^{0}→K^{-}K^{+} and D^{0}→π^{-}π^{+} decays, respectively. This is the first evidence for direct CP violation in a specific D^{0} decay.