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Since the prognosis of patients with pancreatic cancer is very poor and there is a lack of treatment methods, this study is performed to investigate the function of PITX2 in pancreatic stellate cells (PSCs) in the progression of pancreatic cancer. Scientific hypotheses are proposed according to bioinformatics analysis and tissue microarray analysis. Stable knockdown of PITX2 in PSCs is achieved through lentiviral infection. The relative expressions of PITX2, α-SMA, vimentin, CTNNB1, AXIN1 and LEF1 are measured in wild-type PSCs and PITX2-knockdown PSCs. Proliferative capacity is measured by EdU assay. After coculture with PSCs, the proliferation, invasion and migration capacity of pancreatic cancer cells are tested. EMT and Wnt/β-catenin downstream genes of pancreatic cancer cells are investigated to reveal the potential mechanism. Bioinformatics analysis reveals that the PITX2 gene is highly expressed in stromal cells in pancreatic cancer and is correlated with squamous-type PDAC. Analysis of PDAC tissue microarray further demonstrates that high PITX2 level in stromal cells is correlated with poor prognosis in PDAC. After stable knockdown of PITX2 in PSCs, the relative protein levels of α-SMA, vimentin, CTNNB1, AXIN1 and LEF1 are decreased, and the proliferative capacity of PSCs is also decreased. After coculture with PSCs, in which PITX2 expression is downregulated, the proliferation, invasion and migration capacities of pancreatic cancer cells are inhibited. Thus, our results show that PITX2-silenced PSCs inhibit the growth, migration and invasion of pancreatic cancer cells via reduced EMT and Wnt/β-catenin signaling.

In order to explore the characteristic flavor compounds and to infer the possible main flavor precursors in irradiated pigeon meat, the changes of volatile compounds and lipid metabolites in irradiated pigeon meat were analyzed by headspace solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) and ultra-high performance liquid chromatography-tandem quadrupole time-of-flight high-resolution tandem mass spectrometry (UPLC-Triple-TOF MS/MS). The results showed that hydrocarbon and aldehydes were the major volatile components in pigeon meat. There were 10 key flavor components identified, among which, nonanal, (E)-2-hexenal, decanal, hexanal, (E)-2-octenal, (E,E)-2,4-nonadienal, octanal, 2,4-decadienal, and 1-octen-3-ol substances were derived from lipid oxidation, and nonanal aldehydes such as aldehydes, decanal, and hexanal may be generated by the decomposition of oleic and linoleic acids. Fatty acids (FA), AcylCarnitine, plasmenylPE, GlcCer_NDS, AcyGlcADG, lysoPC, Cer_BS, and lysoPS were identified as significantly differential lipid subclasses. Among the 30 lipid molecules with variable importance in the projection (VIP) scores higher than two, 6 contained oleic acid (C18:1) and 10 contained linoleic acid (C18:2). Oleic acid and linoleic acid, precursors for the formation of the characteristic flavor substances of pigeon meat, may be generated by the degradation of these 16 lipid molecules.

In order to investigate the effects of electrical stunning on slaughter stress and post-slaughter meat quality in pigeons, meat-type pigeons aged 28 days under the same feeding conditions were chosen and subjected to electrical stunning with different voltages (50–90 V) before slaughter (0 V as control), and blood biochemical indexes and meat quality indexes were determined after slaughter. Results showed that the postmortem blood levels of creatine kinase (CK), adrenocorticotropic hormone (ACTH) and lactate dehydrogenase (LDH) in pigeons with electrical stunning decreased compared with those in the control group without electrical stunning, and reached the lowest value at an electrical voltage of 60 V. The blood corticosterone (CORT) concentration firstly decreased and then increased with the increase in stunning voltage, and was significantly higher at voltages greater than 70 V than in the control group, indicating increased stress levels at slaughter. Electrical stunning had no significant impact on the postmortem pH of breast meat. Compared with the control group, the brightness value (L*) of pigeon breast meat at 24 h after slaughter slightly decreased while the redness value (a*) increased. The drip loss, cooking loss and shear force of pigeon breast meat were relatively low at voltages of 60–70 V, suggesting good water-holding capacity and tenderness. In conclusion, electrical stunning at 60–70 V can effectively reduce the slaughter stress and improve the meat quality of pigeons after slaughter, which is beneficial for the welfare slaughter of meat-type pigeons.

Background: As the most common primary malignant intracranial tumor, glioblastoma has a poor prognosis with limited treatment options. It has a high propensity for recurrence, invasion, and poor immune prognosis due to the complex tumor microenvironment. Methods: Six groups of samples from four datasets were included in this study. We used consensus ClusterPlus to establish two subgroups by the EMT-related gene. The difference in clinicopathological features, genomic characteristics, immune infiltration, treatment response and prognoses were evaluated by multiple algorithms. By using LASSO regression, multi-factor Cox analysis, stepAIC method, a prognostic risk model was constructed based on the final screened genes. Results: The consensusClusterPlus analyses revealed two subtypes of glioblastoma (C1 and C2), which were characterized by different EMT-related gene expression patterns. C2 subtype with the worse prognosis had the more malignant clinical and pathology manifestations, higher Immune infiltration and tumor-associated molecular pathways scores, and poorer response to treatment. Additionally, our EMT-related genes risk prediction model can provide valuable support for clinical evaluations of glioma. Conclusions: The assessment system and prediction model displayed good performance in independent prognostic risk assessment and individual patient treatment response prediction. This can help with clinical treatment decisions and the development of effective treatments.

BackgroundQuantitative susceptibility mapping (QSM) has recently been applied in humans to quantify the magnetic susceptibility of collagen fibrils in the articular cartilage.PurposeTo determine the ability of QSM to detect cartilage matrix degeneration between normal and early knee osteoarthritis (OA) patients.Study typeProspective.PopulationTwenty-four patients with knee OA and 24 age- and sex-matched healthy controls.Field strength/sequence3D gradient echo, T1 turbo spin echo, and proton density-weighted (PDw) spectral attenuated inversion recovery (SPAIR) sequence at 3.0T.AssessmentScan-rescan reproducibility of the susceptibility values in the cartilage was assessed in control subjects. Cartilage thickness, volume, mean, and standard deviation (SD) of susceptibility values of the cartilage compartments were compared between normal and OA patients. The relationship between magnetic susceptibility values and cartilage lesion grading based on MR images was studied.Statistical testsThe Wilcoxon Rank-Sum test was used to compare cartilage thickness, volume, mean, and SD of susceptibility values between control subjects and OA patients. A Spearman rank correlation was performed to study the relationship between the mean and SD of susceptibility values and the cartilage thinning grades.ResultsThe SD of magnetic susceptibility values in the knee cartilage was significantly lower in OA patients compared with healthy controls, and it decreased with more severe MR grades of cartilage thinning degeneration. Significant correlations between the SD of susceptibility values and cartilage thinning grades were observed with R2  = 0.64 and P = 0.000, R2  = 0.47 and P = 0.002, R2  = 0.52 and P = 0.001, R2  = 0.42 and P = 0.0006, and R2  = 0.67 and P = 0.000 for medial femoral condyle (MFC), lateral femoral condyle (LFC), medial tibia (MT), lateral tibia (LT), and patella, respectively. No significant difference was found in cartilage volume (P = 0.17, P = 0.13, P = 0.20, P = 0.25, and P = 0.18 for MFC, LFC, MT, LT, and patella, respectively) and thickness (P = 0.31, P = 0.19, P = 0.16, P = 0.09, and P = 0.22 for MFC, LFC, MT, LT, and patella, respectively) between OA patients and healthy controls.Data conclusionThe variations of susceptibility values in the knee cartilage decrease with the degree of cartilage degeneration. QSM may be a sensitive indicator for alteration of the collagen network and shows potential to detect cartilage degeneration at early stage.Level of evidence2 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2018.

ERK1/2 are essential proteins mediating mitogen-activated protein kinase signaling downstream of RAS in pancreatic adenocarcinoma (PDAC). Our previous study reveals that ARF6 plays a positive regulatory role in ERK1/2 pathway in a feedback loop manner. A significant part of the literature on ARF6 has emphasized its oncogenic effect as an essential downstream molecule of ERK1/2, and no research has been done on the regulation mechanisms of the feedback loop between ARF6 and the ERK1/2 signaling pathway. In the present study, we explore the gene network downstream of ARF6 and find that DUSP6 may be the critical signal molecule in the positive feedback loop between ARF6 and ERK1/2. Specifically, to elucidate the negative correlations between ARF6 and DUSP6 in pancreatic cancer, we examine their expressions in pancreatic cancer tissues by immunohistochemical staining. Then the impact of DUSP6 on the proliferation and apoptosis of PDAC cells are investigated by gain-of-function and loss-of-function approaches. Mechanism explorations uncover that ARF6 suppresses the expression of DUSP6, which is responsible for the dephosphorylation of ERK1/2. Altogether, these results indicate that DUSP6 plays a tumor-suppressive role and acts as an intermediate molecule between ARF6 and ERK1/2 in PDAC cells, thereby forming a positive feedback loop.

Free‐breathing abdominal chemical exchange saturation transfer (CEST) has great potential for clinical application, but its technical implementation remains challenging. This study aimed to propose and evaluate a free‐breathing abdominal CEST sequence. The proposed sequence employed respiratory gating (ResGat) to synchronize the data acquisition with respiratory motion and performed a water presaturation module before the CEST saturation to abolish the influence of respiration‐induced repetition time variation. In vivo experiments were performed to compare different respiratory motion‐control strategies and B0 offset correction methods, and to evaluate the effectiveness and necessity of the quasi‐steady‐state (QUASS) approach for correcting the influence of the water presaturation module on CEST signal. ResGat with a target expiratory phase of 0.5 resulted in a higher structural similarity index and a lower coefficient of variation on consecutively acquired CEST S0 images than breath‐holding (BH) and respiratory triggering (all p < 0.05). B0 maps derived from the abdominal CEST dataset itself were more stable for B0 correction, compared with the separately acquired B0 maps by a dual‐echo time scan and B0 maps derived from the water saturation shift referencing approach. Compared with BH, ResGat yielded more homogeneous magnetization transfer ratio asymmetry maps at 3.5 ppm (standard deviation: 3.96% vs. 3.19%, p = 0.036) and a lower mean squared difference between scan and rescan (27.52‱ vs. 16.82‱, p = 0.004). The QUASS approach could correct the water presaturation‐induced CEST signal change, but its necessity for in vivo scanning needs further verification. The proposed free‐breathing abdominal CEST sequence using ResGat had an acquisition efficiency of approximately four times that using BH. In conclusion, the proposed free‐breathing abdominal CEST sequence using ResGat and water presaturation has a higher acquisition efficiency and image quality than abdominal CEST using BH. [ABSTRACT FROM AUTHOR]

(1) Background: Spinal cord injuries and diseases necessitate sophisticated tools for accurate diagnosis and treatment planning. However, the lack of reliable phantoms mimicking the complex structure of the spinal cord hinders the development and validation of advanced imaging techniques. This study aims to address this critical unmet need by exploring the application of electrospinning to create polymeric fibers resembling the human spinal cord; (2) Methods: Direct jet coaxial electrospinning (DJ-co-ES) is a specialized electrospinning process characterized by the presence of solely the straight segment of a fluid jet. The research firstly investigates the effects of various solution properties and process parameters on the formation and characteristics of core/shell fibers with polycaprolactone (PCL) as the shell and polyethylene oxide (PEO) as the core. Furthermore, the study explores the potential of these DJ-co-ES fibers as phantoms by measuring various diffusion MRI parameters; (3) Results: Scanning electron microscopy (SEM) revealed the successful production of hollow PCL microfibers (2–12 μm diameter) with smooth, cylindrical morphology and high orientation. The DJ-co-ES process demonstrated optimal stability when utilizing 10 w/v% PCL in DCM/DMF for the shell and 4 w/v% PEO in deionized water for the core. Additionally, the high miscibility between core and shell solvents in other core and shell solutions cases facilitated the production of fibers with smaller diameters. The findings demonstrate that the measured values fall within the range observed in both healthy and diseased spinal cord tissues; (4) Conclusions: This research paves the way for utilizing DJ-co-ES technology to develop reliable phantoms for spinal cord applications, ultimately fostering advancements in diagnosis, treatment, and research related to spinal cord conditions. [ABSTRACT FROM AUTHOR]