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Pancreatic ductal adenocarcinoma (PDAC) usually presents infrequent infiltration of T lymphocytes. The known immune-checkpoint inhibitors to date focus on activating T cells and manifest limited effectiveness in PDAC. SIGLEC15 was identified as a novel tumor-associated macrophage (TAM)-related immune-checkpoint in other cancer types, while its immunosuppressive role and clinical significance remained unclear in PDAC. In our study, SIGLEC15 presented immunosuppressive relevance in PDAC via bioinformatic analysis and expressed on TAM and PDAC cells. SIGLEC15

Pancreatic neuroendocrine tumors (PanNETs) are indolent pancreatic tumors derived from neuroendocrine cells in pancreatic islets. To date, reliable predictors for identifying patients at high risk for recurrence after curative cancer resection are lacking. We aimed to determine independent predictors for high-risk PanNETs and patient outcomes after surgery. We analyzed relevant clinicopathological parameters in 319 consecutive patients of derivation cohort 1 and 106 patients of validation cohort 2 who underwent pancreatectomy and were diagnosed with PanNETs. Association of tumor characteristics with recurrence-free survival (RFS) and overall survival (OS) was evaluated using Cox regression. PanNET grade 3 (G3), pancreatic duct dilatation, and perineural invasion were independent prognostic factors for RFS and were significantly associated with early recurrence (within 1.5 years) of PanNETs after curative resection (P = 0.019, P

Dimethyl ether (DME) is an alternative fuel with significantly reduced particulate (i.e., soot) emissions. The polycyclic aromatic hydrocarbons (PAHs) and soot formation in pure DME flames have not been fully investigated and there is a need to develop a detailed understanding of soot formation from pure DME without the confounding effect of other more sooting hydrocarbons. Therefore, PAH and soot formation in a pure DME /air laminar coflow diffusion flame were explored in this study for two different initial temperatures of the fuel. Gas chromatography /mass spectroscopy (GC/MS), and time-resolved laser-induced incandescence (TiRe-LII) were used to quantitatively measure PAH concentrations, soot volume fractions and primary particle diameters. The experimental results show that, before the appearance of the soot particles, the gas phase reactions are dominated by PAHs smaller than three rings (A3: phenanthrene and anthracene), which decrease along the centerline as the soot volume fractions increase. The primary particle diameters remain relatively constant along the radial profiles at different flame heights, which suggests a moderate surface growth. The numerical predictions of soot and PAHs (smaller than A3) formation are consistent with the measurements (within a factor of 2.4), while the overprediction of the mole fraction of A3 is near an order of magnitude. The model can also capture the effect of increasing the initial fuel temperatures with reasonable accuracy. The experimental results suggest that PAHs are mainly formed by Hydrogen Abstraction Carbon (Acetylene) Addition (HACA), C1 addition is efficient for monoaromatic while the addition of C3 and species containing cyclopentadienyl moiety are not dominant for PAH growth. A database of the PAHs and soot formation has been created for further investigation of this DME flame.

The selective pressure imposed by chemotherapy creates a barrier to tumor eradication and an opportunity for metastasis and recurrence. As a newly discovered stemness marker of pancreatic ductal adenocarcinoma (PDAC), the impact of CD9 on tumor progression and patient's prognosis remain controversial.A total of 179 and 211 PDAC patients who underwent surgical resection with or without neoadjuvant chemotherapy, respectively, were recruited for immunohistochemical analyses of CD9 expression in both tumor and stromal areas prior to statistical analyses to determine the prognostic impact and predictive accuracy of CD9.The relationship between CD9 and prognostic indicators was not significant in the non-neoadjuvant group. Nevertheless, CD9 expression in both tumor (T-CD9) and stromal areas (S-CD9) was significantly correlated with the clinicopathological features in the neoadjuvant group. High levels of T-CD9 were significantly associated with worse OS (p = 0.005) and RFS (p = 0.007), while positive S-CD9 showed the opposite results (OS: p = 0.024; RFS: p = 0.008). Cox regression analyses identified CD9 in both areas as an independent prognostic factor. The TS-CD9 risk-level system was used to stratify patients with different survival levels. The combination of TS-CD9 risk level and TNM stage were accurate predictors of OS (C-index: 0.676; AIC: 512.51) and RFS (C-index: 0.680; AIC: 519.53). The calibration curve of the nomogram composed of the combined parameters showed excellent predictive consistency for 1-year RFS. These results were verified using a validation cohort.Neoadjuvant chemotherapy endows CD9 with a significant prognostic value that differs between tumor and stromal areas in patients with pancreatic cancer.

Chemoresistance is a major obstacle to prolonging pancreatic ductal adenocarcinoma (PDAC) patient survival. TET1 is identified as the most important epigenetic modification enzyme that facilitates chemoresistance in cancers. However, the chemoresistance mechanism of TET1 in PDAC is unknown. This study aimed to determine the role of TET1 in the chemoresistance of PDAC. TET1-associated chemoresistance in PDAC was investigated in vitro and in vivo. The clinical significance of TET1 was analyzed in 228 PDAC patients by tissue microarray profiling. We identified that TET1 downregulation is caused by its promoter hypermethylation and correlates with poor survival in PDAC patients. In vitro and in vivo functional studies performed by silencing or overexpressing TET1 suggested that TET1 is able to suppress epithelial-mesenchymal transition (EMT) and sensitize PDAC cells to 5FU and gemcitabine. Then RNA-seq, whole genome bisulfite sequencing (WGBS) and ChIP-seq were used to explore the TET1-associated pathway, and showed that TET1 promotes the transcription of CHL1 by binding and demethylating the CHL1 promoter, which consequently inhibits the Hedgehog pathway. Additionally, inhibiting Hedgehog signaling by CHL1 overexpression or the Hedgehog pathway inhibitor, GDC-0449, reversed the chemoresistance induced by TET1 silencing. Regarding clinical significance, we found that high TET1 and high CHL1 expression predicted a better prognosis in resectable PDAC patients. In summary, we demonstrated that TET1 reverses chemoresistance in PDAC by downregulating the CHL1-associated Hedgehog signaling pathway. PDAC patients with a high expression levels of TET1 and CHL1 have a better prognosis.

ObjectiveThis study retrospectively characterized the immune infiltrating profile in nonfunctional pancreatic neuroendocrine tumors (NF-PanNETs).MethodsTumor tissues from the 109-patient Fudan cohort and a 73-patient external validation set were evaluated by immunohistochemistry for 9 immune cell types: tumor-infiltrating neutrophils (TINs), tumor-associated macrophages (TAMs), CD11c+ dendritic cells, anti-NCR1+ natural killer (NK) cells, CD4+ and CD8+ T cells, CD45RO+ memory T cells, FOXP3+ regulatory T cells (Tregs), and CD20+ B cells.ResultsTINs were primarily distributed in the intratumoral area, dendritic cells and NK cells were scattered evenly in intratumoral and stromal areas, and Tregs were rarely detected. The remaining 5 cell types were primarily present in peritumoral stroma. Total TINs (P < .001) and TAMs (P = .002) increased as NF-PanNET grade rose. Kaplan-Meier analyses showed that high intratumoral TINs, total TAMs, and stromal CD4+ T-cell infiltration correlated with shorter recurrence-free survival (RFS, P = .010, P = .027, and P = .035, respectively) and overall survival (OS, P = .017, P = .029, and P = .045, respectively). Additionally, high intratumoral CD8+ T cell infiltration correlated with prolonged RFS (P = .039). Multivariate Cox regression demonstrated that intratumoral TINs, World Health Organization (WHO) classification, and eighth edition of the American Joint Committee on Cancer tumor-node-metastasis staging system (AJCC8th TNM) were independent factors for RFS (P = .043, P = .023, and P = .029, respectively), whereas intratumoral TINs and WHO classification were independent factors for OS (P = .010 and P = .007, respectively). Furthermore, the combination of TINs, WHO classification, and AJCC8th TNM remarkably improved prognostic accuracy for RFS. These results have been verified in the external validation set.ConclusionIntratumoral TINs are an independent and unfavorable predictor of postoperative NF-PanNETs. A combination of TINs, WHO classification, and AJCC8th TNM could improve prognostic accuracy for RFS.

BACKGROUND Systemic inflammation and nutrition status play an important role in cancer metastasis. The combined index of hemoglobin, albumin, lymphocyte, and platelet (HALP), consisting of haemoglobin, albumin, lymphocytes, and platelets, is considered as a novel marker to reflect both systemic inflammation and nutrition status. However, no studies have investigated the relationship between HALP and survival of patients with pancreatic cancer following radical resection. AIM To evaluate the prognostic value of preoperative HALP in pancreatic cancer patients. METHODS The preoperative serum levels of hemoglobin, albumin, lymphocyte counts, and platelet counts were routinely detected in 582 pancreatic adenocarcinoma patients who underwent radical resection. The relationship between postoperative survival and the preoperative level of HALP was investigated. RESULTS Low levels of HALP were significantly associated with lymph node metastasis (P = 0.002), poor tumor differentiation (P = 0.032), high TNM stage (P = 0.008), female patients (P = 0.005) and tumor location in the head of the pancreas (P < 0.001). Low levels of HALP were associated with early recurrence [7.3 mo vs 16.3 mo, P < 0.001 for recurrence-free survival (RFS)] and short survival [11.5 mo vs 23.6 mo, P < 0.001 for overall survival (OS)] in patients with resected pancreatic adenocarcinoma. A low level of HALP was an independent risk factor for early recurrence and short survival irrespective of sex and tumor location. CONCLUSION Low levels of HALP may be a significant risk factor for RFS and OS in patients with resected pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) is a lethal malignancy that is usually diagnosed at an advanced stage when curative surgery is no longer an option. Robust diagnostic biomarkers with high sensitivity and specificity for early detection are urgently needed. Systems biology provides a powerful tool for understanding diseases and solving challenging biological problems, allowing biomarkers to be identified and quantified with increasing accuracy, sensitivity, and comprehensiveness. Here, we present a comprehensive overview of efforts to identify biomarkers of PDAC using genomics, transcriptomics, proteomics, metabonomics, and bioinformatics. Systems biology perspective provides a crucial "network" to integrate multi-omics approaches to biomarker identification, shedding additional light on early PDAC detection.

To investigate the possible molecular mechanism of total glycosides of Chishao (Radix Paeoniae Rubra) (TG-RPR) on proliferation and apoptosis of hepatocellular carcinoma cells.The proliferation of TG-RPR on HepG2 cells was detected using the 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The apoptosis of HepG2 cells was measured by annexin V-FITC/double staining. The phosphatase and tensin homolog deleted on chromosome ten (PTEN) / phosphatidylinositol 3-kinase (PI3K) / protein kinase B (Akt) signaling pathway was evaluated by Western Blot and reverse transcription-polymerase chain reaction (RT-PCR).TG-RPR can up-regulation the expression of pro-apoptotic factors such as PTEN and BCL2-Associated X (Bax), down-regulation the expression of anti-apoptotic factors including B-cell lymphoma-2 (Bcl-2), PI3K, and Akt.TG-RPR significantly inhibits the proliferation of HepG2 cells in a dose-dependent manner and promotes apoptosis. These results demonstrated TG-RPR has significant inhibitory effect on HepG2 cells. These results identify a critical role of TG-RPR in proliferation and apoptosis of HepG2 cells via modulating PTEN/PI3K/Akt signaling pathway. TG-RPR may offer a promise as a potential pharmaceutical therapy for hepatocellular carcinoma.

Simple Summary The immunosuppressive microenvironment is closely related to the poor prognosis of patients with PDAC. Tfh cells play an anti-tumor function in various malignant solid tumors; however, the role of Tfh cells in PDAC has not been determined. In this study, we aimed to explore the function of Tfh cells in PDAC, and revealed a novel immunosuppressive mechanism mediated by Tfh cells. Tfh cells promoted the formation of an immunoactive tumor microenvironment by secreting CXCL13 and IL-21, and the high infiltration of Tfh cells correlated with better patient prognosis. However, the anti-tumor function of Tfh cells was inhibited by the PD-L1/PD-1 signaling pathway. Neoadjuvant chemotherapy could further reverse the function of Tfh cells. Our results provided new strategies to remodel the immunoactive tumor microenvironment of PDAC. Abstract Immunosuppression is an important factor for the poor prognosis of pancreatic ductal adenocarcinoma (PDAC). Follicular helper T cells (Tfh cells) play an anti-tumor role in various malignant solid tumors and predict better patient prognosis. In the present study, we aimed to determine the immunosuppressive mechanism associated with Tfh cells and explore a new strategy to improve the tumor microenvironment of PDAC. Flow cytometry was used to detect the infiltration and proportion of Tfh cells in tumor tissues and peripheral blood from patients with PDAC. The spatial correlations of Tfh cells with related immune cells were evaluated using immunofluorescence. The function of Tfh cells was examined using in vitro and in vivo model systems. The high infiltration of Tfh cells predicted better prognosis in patients with PDAC. Tfh cells recruited CD8+ T cells and B cells by secreting C-X-C motif chemokine ligand 13 (CXCL13), and promoted the maturation of B cells into antibody-producing plasma cells by secreting interleukin 21 (IL-21), thereby promoting the formation of an immunoactive tumor microenvironment. The function of Tfh cells was inhibited by the programmed cell death 1 ligand 1 (PD-L1)/programmed cell death 1 (PD-1) signaling pathway in PDAC, which could be reversed using neoadjuvant chemotherapy. Treatment with recombinant CXCL13, IL-21 and Tfh cells alleviated tumor growth and enhanced the infiltration of CD8+ T cells and B cells, as well as B cell maturation in a PDAC mouse model. Our results revealed the important role of Tfh cells in mediating anti-tumor cellular immunity and humoral immunity in PDAC via secreting CXCL13 and IL-21 and determined a novel mechanism of immunosuppression in PDAC.

BACKGROUND Platelets have been reported to participate in tumor cell growth, extravasation, epithelial–mesenchymal transition, metastasis, and drug resistance. However, the importance of platelets in pancreatic neuroendocrine tumor (pNET) lacks adequate literature support. The predictive value of tumor-infiltrating platelets (TIPs) in pNET remains unclear. AIM To investigate the relationship between TIPs and the prognosis of patients with pNET following radical resection. METHODS In total, 113 patients who had undergone radical surgical resection with a pathologic diagnosis of pNET were enrolled in this study. Immunohistochemical analysis of cluster of differentiation 42b (CD42b) expression in the tumor specimens was performed to determine the presence of TIPs. Univariate and multivariate analyses were used to analyze the prognostic value of TIPs. RESULTS TIPs were observed in intratumoral areas in 54 patients. Neither basic characteristics nor preoperative platelet-associated indicators showed a significant relationship with the presence of TIPs (all P > 0.05). Patients with positive intratumoral CD42b expression had worse overall survival (P = 0.005) and recurrence-free survival (P < 0.001) than those with negative intratumoral CD42b expression. Multivariate analysis demonstrated that TIPs were independent prognostic factors for overall survival (P = 0.049) and recurrence-free survival (P = 0.003). Nevertheless, platelet count, mean platelet volume, and platelet-to-lymphocyte ratio were not associated with postoperative survival or recurrence in pNET patients (all P > 0.05). CONCLUSION TIPs are a useful prognostic biomarker for patients with resectable pNET, and their detection represents a promising tool for pNET treatment strategy decisions.

The real-time measurement and reconstruction of three-dimensional temperature are essential when studying the combustion process inside a flame. In the proposed sectioned flame light field imaging model, flame sections are reconstructed based on the characteristics identified using the Lucy-Richardson or nearest neighbor filtering methods, or a joint method involving a combination of both, to improve on the accuracy of two-dimensional temperature reconstruction. Compared to the results of a previous work, the proposed method increases the resolution in the depth of field direction and the extraction of the flame temperature of all sections from the same height ensures the accuracy of the reconstructed temperature distribution across the cross-section of the flame. The relative error when compared to the actual flame is less than 10%. Thus, this approach allows the accurate estimation of the three-dimensional temperature distribution inside a flame, and enables the rapid and effective reconstruction of the three-dimensional temperature field.

Temperature detection is important in flame structure analysis. However, there are few studies focusing on the effect of the distribution of radiative properties on the accuracy of flame temperature reconstruction. Based on an established temperature reconstruction system using sectioned flame imaging, this study adjusts the microlens parameters of a light field camera, combining the nearest neighbor filtering method with the light field refocusing technique, and then accurately reconstructed flame images are obtained. In addition, predicted attenuation coefficient is used to reconstruct flame sections in uniform and nonuniform participating media, to investigate comparatively the effect of nonuniform radiative properties on flame temperature reconstruction. The results show that, the temperature reconstruction results for more than 94% of pixels of the flame imaging are accurate (within 10%), and only few parts at the boundary of the flame have a relative error larger than 10%, and less than 20%. Though the difference of the attenuation coefficient between that estimated for temperature reconstruction and that of the actual flame medium is an important factor influencing the temperature reconstruction accuracy, the effect is investigated in a range using the presented method. Thus, it provides a practical method to reconstruct the flame temperature accurately in unknown radiative properties.

Purpose: The systemic inflammation response index (SIRI), based on peripheral neutrophil, monocyte, and lymphocyte counts, was recently emerged and used as a novel tool in predicting prognosis in different types of cancer. Our aim was to investigate the clinical significance of preoperative SIRI in patients with resectable pancreatic ductal adenocarcinoma (PDAC). Materials and methods: The SIRI was developed in a training cohort of 371 PDAC patients undergoing radical surgery between 2010 and 2013 and validated in a validation cohort of 310 patients from 2014 to 2015. Baseline clinicopathologic characteristics, preoperative laboratory parameters and follow-up information were collected. The optimal cutoff value of SIRI was determined by receiver operating characteristic curve. Univariate and multivariate analysis were performed to analyze the prognostic value of SIRI. Results: The optimal cutoff value of SIRI stratified patients into low SIRI group (≤0.69) and high SIRI group (>0.69). Survival analysis showed that the median overall survival (OS) and recurrence-free survival (RFS) were significantly better in patients with low SIRI. The SIRI was an independent predictor of OS and RFS in multivariate analysis. In addition, SIRI remained its prognostic significance both in patients with early-stage diseases and in patients with normal carbohydrate antigen 19-9 levels. High SIRI indicated poor treatment response for patients who received postoperative adjuvant chemotherapy. Conclusion: Preoperative SIRI was an independent prognostic indicator of poor outcomes in PDAC patients after radical resection. It might assist clinicians to identify high-risk patients and choose the optimal individualized treatment strategy.

Pancreatic ductal adenocarcinoma (PDAC) is a devastating malignancy with poor prognosis. Many preoperative biomarkers can predict postoperative survival of PDAC patients. In this study, we created a novel ratio index based on preoperative liver function test, γ‐glutamyltransferase‐to‐albumin ratio (GAR), and evaluated its prognostic value in predicting clinical outcomes of PDAC patients following radical surgery. We retrospectively enrolled 833 PDAC patients who had underwent radical surgery at our institution between January 2010 and January 2017. Patients were divided into two groups according to the cut‐off value of GAR. Univariate and multivariate survival analysis between the groups were evaluated. TNM stage, GAR, preoperative serum carbohydrate antigen 19‐9 (CA19‐9) and tumor differentiation were combined to generate a more accurate prognostic model. The optimal cut‐off value of GAR was 0.65. Significant correlations were found between GAR and tumor location, tumor size, vascular invasion, obstructive jaundice, biliary drainage and parameters of liver function test. Univariate and multivariate analysis showed that high level of GAR independently predicted poorer postoperative overall survival (OS, P < 0.001) and recurrence‐free survival (RFS, P < 0.001). Subgroup analysis demonstrated that GAR was predictive of survival in patients without biliary obstruction or severely impaired liver function. In addition, integration of GAR, preoperative serum CA19‐9, and tumor differentiation into TNM staging system could better stratify the prognosis for PDAC patients compared with TNM stage alone. Our study demonstrates that preoperative GAR is an independent prognostic factor for prediction of surgical outcomes in PDAC patients. Combination of TNM stage, GAR, preoperative serum CA19‐9, and tumor differentiation can enhance the prognostic accuracy.

Introduction: SRPX2 and RAB31 play important roles in tumorigenesis and metastasis; however, their prognostic value in pancreatic cancer remains unclear. This study aimed to investigate the potential interactions and effects of SRPX2 and RAB31 on the diagnosis and prognosis of pancreatic cancer. Methods: The expression of SRPX2 and RAB31 in pancreatic tumor tissues and cells was evaluated through database mining of the Oncomine, Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) databases, and validated the results through immunohistochemistry (IHC) and Western blot in our clinical database. Protein-protein interactions were explored by immunofluorescence and Co-immunoprecipitation (Co-IP). Two hundred tissue microarray specimens from patients (79 training and 121 validation), who underwent curative pancreatectomy for pancreatic ductal adenocarcinoma (PDAC) were used. Additionally, the association between the SRPX2 and RAB31 and prognosis of PDAC patients after surgery was analyzed. Results: The expression of SRPX2 and RAB31 was highly increased in pancreatic cancer, and there was a significant positive correlation between these two proteins. Co-IP showed the direct interaction between SRPX2 and RAB31. Kaplan-Meier analysis showed that positive expression of SRPX2 and RAB31 was associated with reduced disease-free survival (DFS) and overall survival (OS) of PDAC patients in the training set and the validation sets. Furthermore, multivariate analysis indicated that the 8th edition TNM stage and combination of SRPX2 and RAB31 were independent prognostic factors that associated with OS and DFS in the training, and the validation sets, respectively. Conclusions: The combination of SRPX2 and RAB31 can be important markers for the prognosis of pancreatic cancer.

Colitis-associated cancer (CAC) is the colorectal cancer (CRC) subtype that is difficult to treat, and shows high mortality. The consumption of flavonoid-rich fructus aurantii extracts (FAE) has been associated with multiple beneficial effects including anti-inflammatory and anti-cancer properties, but the potential effects on the colitis-associated carcinogenesis have not been thoroughly investigated. Recent clinical data show that, as yet, few agents clearly inhibited CRC development in long-standing inflammatory bowel diseases. Here, we identified that FAE showed significant efficiency to inhibit HT-29 cell proliferation. The potential of FAE in vivo was further evaluated in an AOM/DSS-induced CAC mouse model. Intriguingly, FAE diminished the number of polyps in mice. Furthermore, FAE inhibited CAC by regulating the gene expression of Notch/ NF-κB/IL-1 signaling pathways. Collectively, these results were indicative of FAE has great potential in CAC prevention and treatment.

Isolation and screening of different compounds from plant extracts are always the key for natural drug research, and the absorbed prototype components have been considered as potential active ingredients. UHPLC combined with quadrupole time-of-flight mass spectrometry (Q-TOF-LC/MS) has been widely used in the research of natural drugs; however, we still need a more effective tool to compare and treat from a raw data. In this study, we provided a fast analytical method to measure the absorbed prototype components and their metabolites both qualitatively and quantitatively based on molecular networking (MN). For example, in Ardisia japonica (Thunb.) Blume, a total of eight absorbed prototype components in rat plasma were identified. Furthermore, pharmacokinetic study was also successfully performed on the eight absorbed prototype components in rat plasma. Our findings have provided important information on the investigation of A. japonica in vivo. More importantly, the MS network analysis pattern serves as an integral solution for qualitative and quantitative determination of phytochemical compounds in natural drugs.

Isolation and screening of different compounds from plant extracts are always the key for natural drug research, and the absorbed prototype components have been considered as potential active ingredients. UHPLC combined with quadrupole time-of-flight mass spectrometry (Q-TOF-LC/MS) has been widely used in the research of natural drugs; however, we still need a more effective tool to compare and treat from a raw data. In this study, we provided a fast analytical method to measure the absorbed prototype components and their metabolites both qualitatively and quantitatively based on molecular networking (MN). For example, in Ardisia japonica (Thunb.) Blume, a total of eight absorbed prototype components in rat plasma were identified. Furthermore, pharmacokinetic study was also successfully performed on the eight absorbed prototype components in rat plasma. Our findings have provided important information on the investigation of A. japonica in vivo. More importantly, the MS network analysis pattern serves as an integral solution for qualitative and quantitative determination of phytochemical compounds in natural drugs.

Splenectomy is routinely performed during distal or total pancreatectomy (DP or TP) for pancreatic ductal adenocarcinoma (PDAC), but information about its oncological value is limited. TER cells, nonimmune cells discovered in the spleens of tumour-bearing mice, are elicited by tumours and promote tumour progression, while their role in the clinical outcomes of patients with PDAC remains unclear. In our study, postoperative specimens from 622 patients who underwent DP or TP with splenectomy were analysed by flow cytometry or immunofluorescence, and the relationship between splenic TER cell count and clinical parameters was calculated. We also purified human TER cells for functional experiments and mechanistic studies. We found that TER cell numbers were increased only in the spleens of patients with PDAC but not in PDAC tissue and adjacent pancreatic tissue. High splenic TER cell counts independently predicted poor prognosis (P < .001) and indicated large tumour size, lymph node metastasis, advanced 8th AJCC/mAJCC stage and high CA19-9 classification (all P < .050) in patients with PDAC. Mechanistic analysis showed that TER cells express artemin, which facilitates the proliferation and invasion of PDAC cells by activating GFRα3-ERK signalling. Our study reveals that TER cell count is an indicator of poor prognosis of PDAC, while splenectomy during pancreatic surgery might provide oncological benefits in addition to ensuring the radical resection of PDAC.

The light field camera has emerged as an optical flame temperature detection device owing to the refocusing feature. Combining this feature with the deconvolution algorithm, a three-dimensional flame temperature distribution can be reconstructed. However, the accuracy of reconstructing the flame temperature is limited by the actual image position. Based on the established flame and light field camera model, the proposed Lucy-Richardson and Nearest Neighbor Filtering joint deconvolution algorithm is applied to sectioned temperature reconstruction. Thus, the effects of image position using light field camera on temperature reconstruction are verified. The relative error of flame temperature reconstruction is less than 10%, if the flame is imaged in the middle of the light field image. However, if the flame is imaged at the image edge, the edge distortion and defocused state of the camera increase the relative error to less than 11% and 14%, respectively. The effects of image positions are not too significant for temperature reconstruction using light field camera.

The flame temperature measurement is significant to study flame structure. However, during the detection process using light field imaging technology, the influence of radiative properties on flame distribution at different positions is hard to evaluate. Therefore, this study simulates the light field imaging of section flames to analyze the influence of radiative properties on flame distribution. A tomographic image is reconstructed from three-dimensional light field imaging, which is evaluated as similar to the section flame images. Then the temperature reconstructed from the tomographic image is compared to the known temperature, with a small relative error, under 10%. In addition, the influence of radiative properties on the accuracy of reconstructed temperature is also analyzed.

With the rise in research on the high-temperature reconstruction of flame, numerical simulation and experimental research on flame detection using plenoptic camera have become more numerous. This study simulates the calibration process of the plenoptic camera to understand the light field imaging process of flame. Based on the simulation platform using the Monte Carlo method, different temperatures generated by the blackbody planes are calibrated, and the relationship between the radiation of the spectral blackbody and the gray value of the detector is obtained. In addition, the effects of refocusing on the temperature reconstruction of the blackbody plane light field imaging at different positions are analyzed. Simulation results show that, by comparing with the experimental results, the simulated flame is found to be almost the same in scale and shape. The result of the temperature reconstruction of the simulated flame is accurate enough to prove that, the numerical simulation of the calibration can improve the confidence of the detector conversion step. Thus, this paper provides a relatively complete simulation platform to obtain and analyze the uncertainty in each step in the process of flame temperature measurement in a light field.