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1.
Tumor tissue is composed of tumor cells and tumor stroma. Tumor stroma contains various immune cells and non-immune stromal cells, forming a complex tumor microenvironment which plays pivotal roles in regulating tumor growth. Recent successes in immunotherapies against tumors, including immune checkpoint inhibitors, have further raised interests in the immune microenvironment of liver carcinoma. The immune microenvironment of tumors is formed because of interactions among tumor cells, immune cells and non-immune stromal cells, including fibroblasts and endothelial cells. Different patterns of immune microenvironment are observed among different tumor subtypes, and their clinicopathological significance and intertumor/intratumor heterogeneity are being intensively studied. Here, we review the immune microenvironment of hepatocellular carcinoma, intrahepatic cholangiocarcinoma and liver metastasis of colorectal adenocarcinoma, focusing on its histopathological appearance, clinicopathological significance, and relationship with histological and molecular classifications. Understanding the comprehensive histopathological picture of a tumor immune microenvironment, in addition to molecular and genetic approaches, will further potentiate the effort for precision medicine in the era of tumor-targeting immunotherapy.  相似文献   
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Gold nanoparticles (Au NPs) hold great promise in food, industrial and biomedical applications due to their unique physicochemical properties. However, influences of the gastrointestinal tract (GIT), a likely route for Au NPs administration, on the physicochemical properties of Au NPs has been rarely evaluated. Here, we investigated the influence of GIT fluids on the physicochemical properties of Au NPs (5, 50, and 100?nm) and their implications on intestinal epithelial permeability in vitro. Au NPs aggregated in fasted gastric fluids and generated hydroxyl radicals in the presence of H2O2. Cell studies showed that GIT fluids incubation of Au NPs affected the cellular uptake of Au NPs but did not induce cytotoxicity or disturb the intestinal epithelial permeability.  相似文献   
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Objective: To determine whether packed red blood cell (PRBC) transfusion affects post-prandial superior mesenteric artery blood flow velocities (SMA BFVs) in very-low birth weight (VLBW) neonates and if so, at what time point after transfusion restoration of previous SMA BFV patterns occurs.

Design/Methods: VLBW pre-term neonates, older than 14 days and tolerating bolus enteral feedings administered every 3?h were enrolled in this prospective observational study. Pulsed Doppler ultrasound was used to measure pre- and post-prandial (at 45?min) time-averaged mean, peak and end diastolic velocities (TAMV, PSV, EDV) immediately before and after 15?ml/kg of PRBC transfusion was given over 3?h; patent ductus arteriosus (PDA) status was also evaluated. Subsequent pre- and post-prandial SMA BFVs were recorded 24 and 48?h after the transfusion.

Results: Pre- and post-prandial measurements were obtained for 21 out of 25 enrolled infants. Post-prandial SMA BFVs were attenuated during the feedings immediately after transfusion; at 24 and 48?h after transfusion, changes in post-prandial SMA BFVs were similar to those measured prior to transfusion; the presence of the PDA did not affect results.

Conclusions: PRBC transfusion blunted SMA BFV responses to feedings immediately after the transfusion with normalization observed 24?h post-transfusion.  相似文献   
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BackgroundPercutaneous endoscopic gastrostomy (PEG) is required for Levodopa/Carbidopa Intestinal Gel (LCIG) delivery in patients with advanced Parkinson's disease (PD) as well as for enteral feeding in a variety of neurological disorders. Buried Bumper Syndrome (BBS) is a serious complication of PEG. The frequency of BBS in patients receiving LCIG treatment has never been reported.ObjectivesTo compare the frequency of BBS in patients on LCIG treatment or on enteral feeding over the past 12 years and identify possible risk factors.MethodsWe reviewed prospectively recorded data from 2009 to 2020 on two case-series: LCIG-treated PD patients and non-PD patients on enteral nutrition. We identified all BBS incidences. Patients’ characteristics, clinical manifestations, BBS management, possible risk factors and outcomes were analyzed.ResultsDuring the 12 years, 35 PD patients underwent PEG insertion for LCIG infusion, and 123 non-PD patients for nutritional support. There were eight cases of BBS in six PD patients (17.1%). Six of them were effectively managed without treatment discontinuation. Of the enteral feeding patients, only one developed BBS (0.8%) (p < 0.001). We identified inappropriate PEG site aftercare, weight gain, early onset PD, longer survival, treatment duration, dementia and PEG system design as potential risk factors for BBS development.ConclusionsBBS occurs more frequently in LCIG patients than in patients receiving enteral feeding. If detected early, it can be successfully managed, and serious sequalae or treatment discontinuation can be avoided. Regular endoscopic follow-up visits of LCIG-treated patients and increased awareness in patients and clinicians are recommended.  相似文献   
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《Journal of thoracic oncology》2021,16(10):1694-1704
IntroductionIn patients with NSCLC, the prognostic significance of the tumor microenvironment (TME) immune composition has been revealed using single- or dual-marker staining on sequential tissue sections. Although these studies reveal that relative abundance and localization of immune cells are important parameters, deeper analyses of the NSCLC TME are necessary to refine the potential application of these findings to clinical care. Currently, the complex spatial relationships between cells of the NSCLC TME and potential drivers contributing to its immunologic composition remain unknown.MethodsWe used multispectral quantitative imaging on the lung adenocarcinoma TME in 153 patients with resected tumors. On a single slide per patient, we evaluated the TME with markers for CD3, CD8, CD14, CD19, major histocompatibility complex II (MHCII), cytokeratin, and 4′,6-diamidino-2-phenylindole (DAPI). Image analysis, including tissue segmentation, phenotyping, and spatial localization, was performed.ResultsSpecimens wherein greater than or equal to 5% of lung cancer cells expressed MHCII (MHCIIhi TME) had increased levels of CD4+ and CD8+ T cells and CD14+ cell infiltration. In the MHCIIhi TME, the immune infiltrate was closer to cancer cells and expressed an activated phenotype. Morphologic image analysis revealed cancer cells in the MHCIIhi TME more frequently interfaced with CD4+ and CD8+ T cells. Patients with an MHCIIhi TME experienced improved overall survival (p = 0.046).ConclusionsLung cancer cell-specific expression of MHCII associates with levels of immune cell infiltration, spatial localization, and activation status within the TME. This suggests that cancer cell-specific expression of MHCII may represent a biomarker for the immune system’s recognition and activation against the tumor.  相似文献   
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《Vaccine》2019,37(31):4382-4391
Cancer-associated fibroblasts (CAFs), major components of the tumor microenvironment (TME), promote tumor growth and metastasis and inhibit the anti-tumor immune response. We previously constructed a DNA vaccine expressing human FAPα, which is highly expressed by CAFs, to target these cells in the TME, and observed limited anti-tumor effects in the 4T1 breast cancer model. When the treatment time was delayed until tumor nodes formed, the anti-tumor effect of the vaccine completely disappeared. In this study, to improve the safety and efficacy, we constructed a new FAPα-targeted vaccine containing only the extracellular domain of human FAPα with a tissue plasminogen activator signal sequence for enhanced antigen secretion and immunogenicity. The number of CAFs was more effectively reduced by CD8+ T cells induced by the new vaccine. This resulted in decreases in CCL2 and CXCL12 expression, leading to a significant decrease in the ratio of myeloid-derived suppressor cells in the TME. Moreover, when mice were treated after the establishment of tumors, the vaccine could still delay tumor growth. To facilitate the future application of the vaccine in clinical trials, we further optimized the gene codons and reduced the homology between the vaccine and the original sequence, which may be convenient for evaluating the vaccine distribution in the human body. These results indicated that the new FAPα-targeted vaccine expressing an optimized secreted human FAPα induced enhanced anti-tumor activity by reducing the number of FAPα+ CAFs and enhancing the recruitment of effector T cells in the 4T1 tumor model mice.  相似文献   
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