Convolutional neural network applied to preoperative venous-phase CT images predicts risk category in patients with gastric gastrointestinal stromal tumors.

OBJECTIVE: The risk category of gastric gastrointestinal stromal tumors (GISTs) are closely related to the surgical method, the scope of resection, and the need for preoperative chemotherapy. We aimed to develop and validate convolutional neural network (CNN) models based on preoperative venous-phase CT images to predict the risk category of gastric GISTs. METHOD: A total of 425 patients pathologically diagnosed with gastric GISTs at the authors' medical centers between January 2012 and July 2021 were split into a training set (154, 84, and 59 with very low/low, intermediate, and high-risk, respectively) and a validation set (67, 35, and 26, respectively). Three CNN models were constructed by obtaining the upper and lower 1, 4, and 7 layers of the maximum tumour mask slice based on venous-phase CT Images and models of CNN_layer3, CNN_layer9, and CNN_layer15 established, respectively. The area under the receiver operating characteristics curve (AUROC) and the Obuchowski index were calculated to compare the diagnostic performance of the CNN models. RESULTS: In the validation set, CNN_layer3, CNN_layer9, and CNN_layer15 had AUROCs of 0.89, 0.90, and 0.90, respectively, for low-risk gastric GISTs; 0.82, 0.83, and 0.83 for intermediate-risk gastric GISTs; and 0.86, 0.86, and 0.85 for high-risk gastric GISTs. In the validation dataset, CNN_layer3 (Obuchowski index, 0.871) provided similar performance than CNN_layer9 and CNN_layer15 (Obuchowski index, 0.875 and 0.873, respectively) in prediction of the gastric GIST risk category (All P >.05). CONCLUSIONS: The CNN based on preoperative venous-phase CT images showed good performance for predicting the risk category of gastric GISTs.

Dynamic radiomics based on contrast-enhanced MRI for predicting microvascular invasion in hepatocellular carcinoma.

OBJECTIVE: To exploit the improved prediction performance based on dynamic contrast-enhanced (DCE) MRI by using dynamic radiomics for microvascular invasion (MVI) in hepatocellular carcinoma (HCC). METHODS: We retrospectively included 175 and 75 HCC patients who underwent preoperative DCE-MRI from September 2019 to August 2022 in institution 1 (development cohort) and institution 2 (validation cohort), respectively. Static radiomics features were extracted from the mask, arterial, portal venous, and equilibrium phase images and used to construct dynamic features. The static, dynamic, and dynamic-static radiomics (SR, DR, and DSR) signatures were separately constructed based on the feature selection method of LASSO and classification algorithm of logistic regression. The receiver operating characteristic (ROC) curves and the area under the curve (AUC) were plotted to evaluate and compare the predictive performance of each signature. RESULTS: In the three radiomics signatures, the DSR signature performed the best. The AUCs of the SR, DR, and DSR signatures in the training set were 0.750, 0.751 and 0.805, respectively, while in the external validation set, the corresponding AUCs were 0.706, 0756 and 0.777. The DSR signature showed significant improvement over the SR signature in predicting MVI status (training cohort: P = 0.019; validation cohort: P = 0.044). After external validation, the AUC value of the SR signature decreased from 0.750 to 0.706, while the AUC value of the DR signature did not show a decline (AUCs: 0.756 vs. 0.751). CONCLUSIONS: The dynamic radiomics had an improved effect on the MVI prediction in HCC, compared with the static DCE MRI-based radiomics models.

Theoretical studies on the local structure and spin Hamiltonian parameters for Cu2+ ions in LiTaO3 crystal.

The local structure and spin Hamiltonian parameters (SHPs) g factors (gx , gy , gz ) and the hyperfine structure constants (Ax , Ay , Az ) for Cu2+ doped in the LiTaO3 crystal are theoretically investigated by the perturbation formulas for a 3d9 ion under rhombically elongated octahedral based on the cluster approach. The impurity Cu2+ was assumed to occupy the host trigonally-distorted octahedral Li+ site and experience the Jahn-Teller (JT) distortion from the host trigonal octahedral [TaO6 ]10- to the impurity rhombically elongated octahedral [CuO6 ]10- . Based on the calculations, the impurity-ligand bond lengths parallel and perpendicular to the C2 -axis are found to be R|| (≈ 2.305 Å) and R⊥ (≈ 2.112 Å) for the studied [CuO6 ]10- cluster, with the planar bond angle θ (≈ 78.2°). Meanwhile, the ground-state wave function for Cu2+ center in LiTaO3 was also obtained. The calculated SHPs based on the above local lattice distortions agree well with the experimental data, and the results are discussed.

Radical Resection Combined With Intestinal Autotransplantation for Locally Advanced Pancreatic Cancer After Neoadjuvant Therapy: A Report of 36 Consecutive Cases.

OBJECTIVE: To achieve radical resection of locally advanced pancreatic ductal adenocarcinoma (PDAC), and tested the safety and benefits of intestinal autotransplantation in pancreatic surgery. BACKGROUND: PDAC has an extremely dismal prognosis. Radical resection was proved to improve the prognosis of patients with PDAC; however, the locally advanced disease had a very low resection rate currently. We explored and evaluated whether the combination of modern advances in systemic treatment and this macroinvasive surgery was feasible in clinical practice. METHODS: Patients diagnosed as PDAC with superior mesenteric artery involvement and with or without celiac trunk involvement were included. Patients were treated with modified-FOLFIRINOX chemotherapy with or without anti-PD-1 antibodies and were applied to tumor resection combined with intestinal autotransplantation. Data on operative parameters, pathologic results, mortality, morbidity, and survival were analyzed. RESULTS: A total of 36 consecutive cases were applied to this strategy and underwent radical resection combined with intestinal autotransplantation. Among these patients, 24 of them received the Whipple procedure, 11 patients received total pancreatectomy, and the other 1 patient received distal pancreatectomy. The median operation time was 539 minutes. Postoperative pathology showed an R0 resection rate of 94.4%, and tumor invasion of a superior mesenteric artery or superior mesenteric vein was confirmed in 32 patients. The median number of dissected lymph nodes was 43, and 25 patients were positive for lymph node metastasis. The median time of intensive care unit stay was 4 days. Two patients died within 30 days after surgery due to multiorgan failure. The severe postoperative adverse events (equal to or higher than grade 3) were observed in 12 out of 36 patients, and diarrhea, gastroparesis, and abdominal infection were the most frequent adverse events. Postoperative hospital stay was averagely of 34 days. The recurrence-free survival is 13.6 months. The median overall survival of patients after diagnosis and after surgery was 21.4 months and 14.5 months, respectively. CONCLUSIONS: Our attempt suggests the safety of this modality and may be clinically beneficial for highly selected patients with PDAC. However, the experience in multidisciplinary pancreatic cancer care and intestinal transplantation is warranted.

Predicting Microvascular Invasion in Hepatocellular Carcinoma Using CT-based Radiomics Model.

Background Prediction of microvascular invasion (MVI) may help determine treatment strategies for hepatocellular carcinoma (HCC). Purpose To develop a radiomics approach for predicting MVI status based on preoperative multiphase CT images and to identify MVI-associated differentially expressed genes. Materials and Methods Patients with pathologically proven HCC from May 2012 to September 2020 were retrospectively included from four medical centers. Radiomics features were extracted from tumors and peritumor regions on preoperative registration or subtraction CT images. In the training set, these features were used to build five radiomics models via logistic regression after feature reduction. The models were tested using internal and external test sets against a pathologic reference standard to calculate area under the receiver operating characteristic curve (AUC). The optimal AUC radiomics model and clinical-radiologic characteristics were combined to build the hybrid model. The log-rank test was used in the outcome cohort (Kunming center) to analyze early recurrence-free survival and overall survival based on high versus low model-derived score. RNA sequencing data from The Cancer Image Archive were used for gene expression analysis. Results A total of 773 patients (median age, 59 years; IQR, 49-64 years; 633 men) were divided into the training set (n = 334), internal test set (n = 142), external test set (n = 141), outcome cohort (n = 121), and RNA sequencing analysis set (n = 35). The AUCs from the radiomics and hybrid models, respectively, were 0.76 and 0.86 for the internal test set and 0.72 and 0.84 for the external test set. Early recurrence-free survival (P < .01) and overall survival (P < .007) can be categorized using the hybrid model. Differentially expressed genes in patients with findings positive for MVI were involved in glucose metabolism. Conclusion The hybrid model showed the best performance in prediction of MVI. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Summers in this issue.

Sintilimab Plus Modified FOLFIRINOX in Metastatic or Recurrent Pancreatic Cancer: The Randomized Phase II CISPD3 Trial.

BACKGROUND: Folinic acid, fluorouracil, irinotecan, and oxaliplatin (FOLFIRINOX) or modified FOLFIRINOX (mFFX) is the first-line standard of care for metastatic pancreatic adenocarcinoma; effective and safe treatment strategies are needed as survival remains poor. Sintilimab, a human immunoglobulin G4 monoclonal antibody for programmed cell death-1, has shown efficacy in various cancers. We evaluated the efficacy and safety of sintilimab with mFFX for metastatic/recurrent pancreatic ductal adenocarcinoma in China. PATIENTS AND METHODS: This was a single-center, randomized, controlled, open-label phase II study. Patients were assigned 1:1 to sintilimab + mFFX or mFFX (n = 55, each). RESULTS: In the intention-to-treat population, median overall survivals (primary endpoint) were similar in the sintilimab + mFFX and mFFX groups: 10.9 and 10.8 months, respectively [hazard ratio (HR) 1.07, 95% confidence interval (CI) 0.69-1.68]. The objective response rate was higher [50.0% (95% CI 34.6-65.4%) versus 23.9% (95% CI 11.1-36.7%)] in the sintilimab + mFFX group (P < 0.05). Median (HR, 95% CI) progression-free survival and disease control rates (95% CI) were also similar at 5.9 and 5.7 months (0.93, 0.62-1.40), and 84.1% (72.8-95.3%) and 71.7%, (58.2-85.3%), respectively. Incidences of grade ≥ 3 treatment-emergent adverse events were 84.9% (45/53) and 74.1% (40/54), and that of grade ≥ 3 immune-related adverse events were 5.7% (3/53) and 0 in each group, respectively. CONCLUSIONS: The study did not meet its primary endpoint, no clear survival benefit was observed, and the benefit of sintilimab + mFFX for advanced pancreatic cancer was not supported; however, the findings suggest that using this regimen for pancreatic cancer is feasible, has an acceptable safety profile, and leads to an objective response rate of 50%. Trial registration ClinicalTrials.Gov; NCT03977272.

Normalization of tumor markers and a clear resection margin affect progression-free survival of patients with unresectable pancreatic cancer who have undergone conversion surgery.

BACKGROUND: With the advent of intensive combination regimens, an increasing number of patients with unresectable pancreatic cancer (UPC) have regained the opportunity for surgery. We investigated the clinical benefits and prognostic factors of conversion surgery (CS) in UPC patients. METHODS: We retrospectively enrolled patients with UPC who had received CS following first-line systemic treatment in our center between 2014 to 2022. Treatment response, safety of the surgical procedure and clinicopathological data were collected. We analyzed the prognostic factors for postoperative survival among UPC patients who had CS. RESULTS: Sixty-seven patients with UPC were enrolled (53 with locally advanced pancreatic cancer (LAPC) and 14 with metastatic pancreatic cancer (MPC)). The duration of preoperative systemic treatment was 4.17 months for LAPC patients and 6.52 months for MPC patients. All patients experienced a partial response (PR) or had stable disease (SD) preoperatively according to imaging. Tumor resection was unsuccessful in four patients and, finally, R0 resection was obtained in 81% of cases. Downstaging was determined pathologically in 87% of cases; four patients achieved a complete pathological response. Median postoperative-progression-free survival (PO-PFS) was 9.77 months and postoperative overall survival (PO-OS) was 31.2 months. Multivariate logistic regression analyses revealed that the resection margin and postoperative changes in levels of tumor markers were significant prognostic factors for PO-PFS. No factors were associated significantly with PO-OS according to multivariate analyses. CONCLUSIONS: CS is a promising strategy for improving the prognosis of UPC patients. The resection margin and postoperative change in levels of tumor markers are the most important prognostic factors for prolonged PFS. Multidisciplinary treatment in high-volume centers is strongly recommended. Prospective studies must be undertaken to resolve the various problems regarding optimal regimens, the duration of treatment, and detailed criteria for CS.

Studies on the EPR parameters and local angular distortion for the tetragonal Cu2+ center in CaWO4 crystal.

The electron paramagnetic resonance (EPR) parameters-g factors gi (i = || and ⊥) and hyperfine structure constants Ai (M) and Ai (N), with M and N belonging to isotopes 63 Cu2+ and 65 Cu2+ -and local structure of Cu2+ ion occupying W6+ site in CaWO4 crystal are theoretically studied based on the perturbation formulas of these parameters for a 3d9 ion under tetragonally elongated tetrahedra. In these formulas, the ligand orbital (LO) and spin-orbit coupling (SOC) contributions are included due to the shorter impurity-ligand distance R (≈1.83 Å) and hence the strong covalency of the studied [CuO4 ]6- cluster, and the related molecular orbital coefficients are quantitatively determined from the cluster approach in a uniform way; meanwhile, the required crystal field (CF) parameters for the tetragonally distorted tetrahedron (TDT) are estimated from the superposition model and the local structure of the impurity Cu2+ center. According to the calculation, the bond angle θ between the four equivalent Cu2+ -O2- bonds and the C4 axis in the CaWO4 :Cu2+ is found to be about 2.1° smaller than that (θ0 ≈ 54.74°) for an ideal tetrahedron due to the Jahn-Teller (JT) effect and the size mismatch. The fitted results agree well with the observed values, and the validity of the present assignment for the local structure of the Cu2+ center is also discussed.

Synchronous pancreatic cancer and pancreatic serous cystic neoplasm: A case report.

Pancreatic cancer is a highly malignant digestive tract tumour with a poor prognosis. We herein report the case of a 58-year-old female who presented, in June 2019, because of upper abdominal discomfort after eating. Initially, the patient was diagnosed with chronic non-atrophic gastritis with erosion and multiple gastric polyps by gastroscopic examination. Subsequently, CT and MRI examinations revealed that dilatation of the pancreatic duct and low-density nodular shadows enhanced in the neck and body of the pancreas. Endoscopic ultrasonography identified the echo foci in the same position. Additionally, a high-level of CA19-9 in the patient's serum was noted, which was a tumour marker of pancreatic cancer. Finally, the patient was diagnosed with poorly differentiated pancreatic cancer with squamous carcinoma and plasmacytoid microcystic adenoma. In conclusion, imaging examination has exhibited a vital functional role in the diagnosis of many cancers, which help gain valuable treatment time and prolong the life of patients.

Comprehensive Clinical Analysis of Gallbladder Neuroendocrine Neoplasms: A Large-Volume Multicenter Study During One Decade.

BACKGROUND: This study aimed to comprehensively investigate the clinicopathologic characteristics and therapeutic situations of gallbladder neuroendocrine neoplasms (GB-NENs) in the real world via a multicenter, large-scale cohort study. METHODS: The study searched for patients in 143 hospitals in China and enrolled 154 patients with GB-NENs diagnosed in 40 hospitals between 2004 and 2021. Clinicopathologic characteristics and therapeutic approaches were analyzed retrospectively. RESULTS: The median age at the initial diagnosis of the patients with GB-NENs was 63 years (range 33-83 years), and 61.7% of the patients were women. Tumor-node-metastasis staging classified 92 patients as stage 3 or above. Based on the 2019 World Health Organization classification, 96 cases (62.3%) were confirmed pathologically as poorly differentiated neuroendocrine carcinomas, 13 cases (8.4%) as well-differentiated neuroendocrine tumors, and 45 cases as mixed neuroendocrine-non-neuroendocrine neoplasms. The liver was the most frequent metastatic site. Immunohistochemistry showed that synaptophysin was most frequently positive (80.4%), followed by chromogranin A (61.7%), and CD56 (58.4%). Computed tomography and magnetic resonance imaging showed more common clear boundaries (25/39 cases) and invasive growth features (27 cases). None of these cases had an accurate diagnosis before surgery, with a misdiagnosis rate of 100%. Surgical resection is the main treatment, and platinum-based chemotherapeutic regimens were preferred as adjuvant therapies for patients with GB-NENs. The available survival data for 74 patients showed an overall survival rate of 59% at 1 year, 33% at 3 years, and 29% at 5 years. No significant difference was found between the patients treated with and those treated without adjuvant chemotherapy. CONCLUSIONS: Gallbladder neuroendocrine neoplasms have high malignancy and a poor prognosis. Importantly, this large-scale cohort study significantly improves our understanding of GB-NENs and will benefit the exploration of its mechanism and treatment modes. Further investigation is necessary to explore the management of this disease.

Preoperative Microvascular Invasion Prediction to Assist in Surgical Plan for Single Hepatocellular Carcinoma: Better Together with Radiomics.

BACKGROUND: Prediction models with or without radiomic analysis for microvascular invasion (MVI) in hepatocellular carcinoma (HCC) have been reported, but the potential for model-predicted MVI in surgical planning is unclear. Therefore, we aimed to explore the effect of predicted MVI on early recurrence after anatomic resection (AR) and non-anatomic resection (NAR) to assist surgical strategies. METHODS: Patients with a single HCC of 2-5 cm receiving curative resection were enrolled from 2 centers. Their data were used to develop (n = 230) and test (n = 219) two prediction models for MVI using clinical factors and preoperative computed tomography images. The two prediction models, clinico-radiologic model and clinico-radiologic-radiomic (CRR) model (clinico-radiologic variables + radiomic signature), were compared using the Delong test. Early recurrence based on model-predicted high-risk MVI was evaluated between AR (n = 118) and NAR (n = 85) via propensity score matching using patient data from another 2 centers for external validation. RESULTS: The CRR model showed higher area under the curve values (0.835-0.864 across development, test, and external validation) but no statistically significant improvement over the clinico-radiologic model (0.796-0.828). After propensity score matching, difference in 2-year recurrence between AR and NAR was found in the CRR model predicted high-risk MVI group (P = 0.005) but not in the clinico-radiologic model predicted high-risk MVI group (P = 0.31). CONCLUSIONS: The prediction model incorporating radiomics provided an accurate preoperative estimation of MVI, showing the potential for choosing the more appropriate surgical procedure between AR and NAR.

Age-Period-Cohort Analysis of Ischemic Heart Disease Morbidity and Mortality in China, 1990-2019.

BACKGROUND: The disease burden of ischemic heart disease (IHD) continues to increase. This study aimed to assess the age, period, and cohort effects on the long-term trends of IHD incidence and mortality in China from 1990 to 2019.Methods and Results: The data were obtained from the Global Burden of Disease Study (GBD) 2019, and the age-standardized incidence/mortality rate (ASIR/ASMR) was calculated. The age-period-cohort (APC) model, which is a generalized linear model revealing the correlation of disease rate and attained age, period, and cohort, was applied to estimate the net drift (estimated annual percentage change [EAPC]s), the local drifts (age-specific EAPCs), the age, period, and cohort effects. The analyses elucidated that the ASIR and ASMR of IHD declined after 2013. The net drift of incidence was 0.212% in females, and the net drift of mortality was 0.371% in males. The local drifts of mortality were above 0 in males aged 20-84 years and in females aged 65-84 years. The age effects showed elevated trends during the study period. The period effects declined after 2013. The cohort effects of mortality in males were higher than that in females. CONCLUSIONS: The decrease of ASIR and ASMR indicated that measures to prevent IHD have been effective in China. However, the cardiovascular health of the elderly and males should be considered in future policy decisions.

Comparison of MRI and CT for the Prediction of Microvascular Invasion in Solitary Hepatocellular Carcinoma Based on a Non-Radiomics and Radiomics Method: Which Imaging Modality Is Better?

BACKGROUND: Computed tomography (CT) and magnetic resonance imaging (MRI) are both capable of predicting microvascular invasion (MVI) in hepatocellular carcinoma (HCC). However, which modality is better is unknown. PURPOSE: To intraindividually compare CT and MRI for predicting MVI in solitary HCC and investigate the added value of radiomics analyses. STUDY TYPE: Retrospective. SUBJECTS: Included were 402 consecutive patients with HCC (training set:validation set = 300:102). FIELD STRENGTH/SEQUENCE: T2-weighted, diffusion-weighted, and contrast-enhanced T1-weighted imaging MRI at 3.0T and contrast-enhanced CT. ASSESSMENT: CT- and MR-based radiomics signatures (RS) were constructed using the least absolute shrinkage and selection operator regression. CT- and MR-based radiologic (R) and radiologic-radiomics (RR) models were developed by univariate and multivariate logistic regression. The performance of the RS/models was compared between two modalities. To investigate the added value of RS, the performance of the R models was compared with the RR models in HCC of all sizes and 2-5 cm in size. STATISTICAL TESTS: Model performance was quantified by the area under the receiver operating characteristic curve (AUC) and compared using the Delong test. RESULTS: Histopathologic MVI was identified in 161 patients (training set:validation set = 130:31). MRI-based RS/models tended to have a marginally higher AUC than CT-based RS/models (AUCs of CT vs. MRI, P: RS, 0.801 vs. 0.804, 0.96; R model, 0.809 vs. 0.832, 0.09; RR model, 0.835 vs. 0.872, 0.54). The improvement of RR models over R models in all sizes was not significant (P = 0.21 at CT and 0.09 at MRI), whereas the improvement in 2-5 cm was significant at MRI (P < 0.05) but not at CT (P = 0.16). DATA CONCLUSION: CT and MRI had a comparable predictive performance for MVI in solitary HCC. The RS of MRI only had significant added value for predicting MVI in HCC of 2-5 cm. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.

Preoperative transarterial chemoembolization for barcelona clinic liver cancer stage A/B hepatocellular carcinoma beyond the milan criteria: a propensity score matching analysis.

BACKGROUND: Debate continues about the benefits of preoperative transarterial chemoembolization (TACE) for treatment of hepatocellular carcinoma (HCC). This study aimed to assess the impact of preoperative TACE on long-term outcomes after curative resection for HCC beyond the Milan criteria. METHODS: Patients who underwent HCC resection exceeding the Milan criteria without macrovascular invasion between 2015 and 2018 were identified (n = 393). Short- and long-term outcomes were compared between patients who underwent preoperative TACE and patients who did not before and after propensity score matching (PSM). Factors associated with recurrence after resection were analyzed. RESULTS: 100 patients (25.4%) underwent preoperative TACE. Recurrence-free survival (RFS) and overall survival (OS) were comparable with patients who underwent primary liver resection. 7 patients (7.0%) achieved total necrosis with better RFS compared with patients who had an incomplete response to TACE (P=0.041). PSM created 73 matched patient pairs. In the PSM cohort, preoperative TACE improved RFS (P=0.002) and OS (P=0.003). The maximum preoperatively diagnosed tumor diameter (HR 3.230, 95% CI: 1.116-9.353; P=0.031) and hepatitis B infection (HR 2.905, 95%CI: 1.281-6.589; P=0.011) were independently associated with favorable RFS after HCC resection. CONCLUSION: Preoperative TACE made no significant difference to perioperative complications and was correlated with an improved prognosis after surgical resection for patients with HCC beyond the Milan criteria.

Cytosine methylations in the promoter regions of genes involved in the cellular oxidation equilibrium pathways affect rice heat tolerance.

BACKGROUND: High temperatures, particularly at night, decrease rice yield and quality. As high nighttime temperatures (HNTs) become increasingly frequent due to climate change, it is imperative to develop rice crops that tolerate HNTs. DNA methylation may represent a potential avenue for HNT-tolerant rice strain development, as this mechanism regulates gene activity and cellular phenotype in response to adverse environmental conditions without changing the nucleotide sequence. RESULTS: After HNT exposure, the methylation patterns of cytosines in the CHH context differed noticeably between two coisogenic rice strains with significantly different levels in heat tolerance. Methylation differences between strains were primarily observed on successive cytosines in the promoter or downstream regions of transcription factors and transposon elements. In contrast to the heat-sensitive rice strain, the regions 358-359 bp and 2-60 bp downstream of two basal transcriptional factors (TFIID subunit 11 and mediator of RNA polymerase II transcription subunit 31, respectively) were fully demethylated in the heat-tolerant strain after HNT exposure. In the heat-tolerant strain, HNTs reversed the methylation patterns of successive cytosines in the promoter regions of various genes involved in abscisic acid (ABA)-related reactive oxygen species (ROS) equilibrium pathways, including the pentatricopeptide repeat domain gene PPR (LOC_Os07g28900) and the homeobox domain gene homeobox (LOC_Os01g19694). Indeed, PRR expression was inhibited in heat-sensitive rice strains, and the methylation rates of the cytosines in the promoter region of PRR were greater in heat-sensitive strains as compared to heat-tolerant strains. CONCLUSIONS: After HNT exposure, cytosines in the CHH context were more likely than cytosines in other contexts to be methylated differently between the heat-sensitive and heat-tolerant rice strains. Methylation in the promoter regions of the genes associated with ABA-related oxidation and ROS scavenging improved heat tolerance in rice. Our results help to clarify the molecular mechanisms underlying rice heat tolerance.

Development of a Novel Multiparametric MRI Radiomic Nomogram for Preoperative Evaluation of Early Recurrence in Resectable Pancreatic Cancer.

BACKGROUND: In pancreatic cancer, methods to predict early recurrence (ER) and identify patients at increased risk of relapse are urgently required. PURPOSE: To develop a radiomic nomogram based on MR radiomics to stratify patients preoperatively and potentially improve clinical practice. STUDY TYPE: Retrospective. POPULATION: We enrolled 303 patients from two medical centers. Patients with a disease-free survival ≤12 months were assigned as the ER group (n = 130). Patients from the first medical center were divided into a training cohort (n = 123) and an internal validation cohort (n = 54). Patients from the second medical center were used as the external independent validation cohort (n = 126). FIELD STRENGTH/SEQUENCE: 3.0T axial T1 -weighted (T1 -w), T2 -weighted (T2 -w), contrast-enhanced T1 -weighted (CET1 -w). ASSESSMENT: ER was confirmed via imaging studies as MRI or CT. Risk factors, including clinical stage, CA19-9, and radiomic-related features of ER were assessed. In addition, to determine the intra- and interobserver reproducibility of radiomic features extraction, the intra- and interclass correlation coefficients (ICC) were calculated. STATISTICAL TESTS: The area under the receiver-operator characteristic (ROC) curve (AUC) was used to evaluate the predictive accuracy of the radiomic signature in both the training and test groups. The results of decision curve analysis (DCA) indicated that the radiomic nomogram achieved the most net benefit. RESULTS: The AUC values of ER evaluation for the radiomics signature were 0.80 (training cohort), 0.81 (internal validation cohort), and 0.78 (external validation cohort). Multivariate logistic analysis identified the radiomic signature, CA19-9 level, and clinical stage as independent parameters of ER. A radiomic nomogram was then developed incorporating the CA19-9 level and clinical stage. The AUC values for ER risk evaluation using the radiomic nomogram were 0.87 (training cohort), 0.88 (internal validation cohort), and 0.85 (external validation cohort). DATA CONCLUSION: The radiomic nomogram can effectively evaluate ER risks in patients with resectable pancreatic cancer preoperatively, which could potentially improve treatment strategies and facilitate personalized therapy in pancreatic cancer. LEVEL OF EVIDENCE: 4 Technical Efficacy: Stage 4 J. Magn. Reson. Imaging 2020;52:231-245.

Statin Pretreatment Might Be Associated with Decreased Myocardial Injury After Ischemic Stroke.

BACKGROUND: Myocardial injury is a complication of stroke associated with unfavorable outcome, with the elevation of cardiac troponin as the most sensitive marker. In this study, we aimed at investigating the association between statin pretreatment and poststroke myocardial injury. METHODS: Six hundred seventy-one patients diagnosed as acute ischemic stroke were enrolled. According to the histories of statin pretreatment before stroke, patients were categorized into nonstatin (n = 474) and statin groups (n = 197), with the latter further divided into low-dosage, standard-dosage, and high-dosage subgroups according the dosages of statins. The level of troponin-T was tested and troponin-T level ≥14 ng/l was identified to indicate the presence of myocardial injury. The level of troponin-T and the prevalence of myocardial injury was compared between groups. Logistic regression was used to identify the effect of statin pretreatment for the presence of post-stroke myocardial injury. RESULTS: Statin users had lower levels of troponin-T after stroke, with the level of troponin-T being the lowest in the high-dosage subgroup. The results of logistic regression showed that statin pretreatment and high-dosage statin were independent protective factors for the elevation of troponin-T levels. CONCLUSIONS: Statin pretreatment might be associated with the decreased myocardial injury after ischemic stroke.

Morphological classification of intraductal papillary neoplasm of the bile duct.

OBJECTIVES: To investigate the morphological classification of intraductal papillary neoplasm of the bile duct (IPNB), as well as morphological differences between IPNB without mucin secretion (IPNB-NM) and IPNB with mucin secretion (IPMN-B). METHODS: Eighty-one patients with IPNB were retrospectively analysed. Imaging examinations included computed tomography (CT), magnetic resonance imaging (MRI), gadolinium-ethoxybenzyl-diethylenetriaminepentaacetic acid (Gd-EOB-DTPA)-enhanced MRI and positron emission tomography-computed tomography (PET-CT). According to the morphology of tumours and extent of bile duct dilations, IPNB was classified into seven types: I, upstream-ductectatic type; II, typical type; III, superficial-spreading type; IV, no-mass-forming type; V, intrahepatic-cystic type; VI, extrahepatic-cystic type; and VII, infiltrating type. RESULTS: Thirteen IPNB-NM patients comprised type I (11 cases), type II (1 case) and type VII (1 case); 68 IPMN-B patients comprised type I (2 cases), type II (30 cases), type III (6 cases), type IV (11 cases), type V (13 cases), type VI (2 cases) and type VII (4 cases). Bile duct dilations were more severe in IPMN-B than in IPNB-NM. PET-CT and Gd-EOB-DTPA-enhanced MRI clearly demonstrated the extension of infiltrating IPNB. CONCLUSIONS: IPNB can be classified into seven morphological types. IPNB-NM and IPMN-B have different morphological features. KEY POINTS: • IPNB can be classified into seven morphological types. • IPNB-NM and IPMN-B have different morphological features. • Enhanced CT and MRI can display different types of IPNB. • Morphological classification of IPNB facilitates management of the disease.

Highly polarization sensitive photodetectors based on quasi-1D titanium trisulfide (TiS3).

Photodetectors with high polarization sensitivity are in great demand in advanced optical communication. Here, we demonstrate that photodetectors based on titanium trisulfide (TiS3) are extremely sensitive to polarized light (from visible to the infrared), due to its reduced in-plane structural symmetry. By density functional theory calculation, TiS3 has a direct bandgap of 1.13 eV. The highest photoresponsivity reaches 2500 A W-1. What is more, in-plane optical selection caused by strong anisotropy leads to the photoresponsivity ratio for different directions of polarization that can reach 4:1. The angle-dependent photocurrents of TiS3 clearly display strong linear dichroism. Moreover, the Raman peak at 370 cm-1 is also very sensitive to the polarization direction. The theoretical optical absorption of TiS3 is calculated by using the HSE06 hybrid functional method, in qualitative agreement with the observed experimental photoresponsivity.