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Background/Aims: To correlate the endoscopic characteristics with the histopathology of specimens of esophageal high-grade intraepithelial neoplasia obtained by endoscopic submucosal dissection (ESD). Methods: This was a retrospective study developed from January 2010 to December 2015. The study included 169 patients who underwent ESD and were diagnosed with esophageal high-grade intraepithelial neoplasia according to endoscopic forceps biopsy, Lugol staining, endoscopic ultrasonography, computed tomography, and Narrow-Band Imaging. The demographic, endoscopic, and histopathologic characteristics were analyzed. Results: A total of 19 cases (11.2%) had a change in diagnosis after histopathology exam and 16 (9.5%) needed a change in established treatment. An increase in the severity of disease was correlated with a lesion size > 2 cm, less than 4 samples in biopsy, and depressed or excavated patterns (p < 0.05). One hundred forty patients (82.8%) underwent curative resection. Lesions with leukoplakia (p < 0.001) and negative Lugol staining (p = 0.028) were independent risk factor for non-curative resection. Conclusion: This study confirms that lesion size > 2 cm, depressed and excavated patterns, and ≤4 biopsy samples are independent risk factors for histological grade changes compared to pre-endoscopic treatment diagnosis. Similarly, leukoplakia and no Lugol staining of lesions are independent risk factors for non-curative resection. [ABSTRACT FROM AUTHOR]

Background/Aims: Chronic kidney disease (CKD) is often accompanied by hyperlipidemia, which accelerates progression of the disease. Podocyte injury can lead to dysfunction of the glomerular filtration barrier, which is associated with proteinuria, a risk marker for the progression of CKD. Our previous studies demonstrated that palmitic acid (PA) can induce podocyte apoptosis; however, the underlying mechanisms are unclear. In the present study, we investigated the specific molecular mechanisms of PA-induced apoptosis in cultured podocytes. Methods: We cultured mouse podocytes and treated them with PA. Then, cell viability was measured using the Cell Counting Kit-8 colorimetric assay, lipid uptake was assessed by Oil Red O staining and boron-dipyrromethene staining, apoptosis was measured by flow cytometry, mitochondrial injury was assessed by JC-1 staining and transmission electron microscopy, and mitochondrial production of reactive oxygen species (ROS) was evaluated by fluorescence microscopy using the MitoSOX Red reagent. The effects of PA on the mitochondria-mediated caspase activation pathway were investigated by examining the expression of caspase-8, cleaved caspase-9, cleaved caspase-3, cleaved poly (ADP-ribose) polymerase (PARP), B-cell lymphoma 2 (Bcl-2), Bax, Bid, cytochrome c, and Fas-associated protein with death domain (FADD) using western blotting. The translocation of Bax and cytochrome c were detected by immunofluorescence. Results: PA treatment significantly increased lipid accumulation and induced podocyte apoptosis. We investigated whether the two primary apoptosis signaling pathways (death receptor-mediated pathway and mitochondria-mediated pathway) were involved in the execution of PA-induced podocyte apoptosis, and found that the levels of FADD, caspase-8, and Bid did not significantly change during this process. Meanwhile, PA treatment induced an increase in Bax protein expression and a decrease in Bcl-2 protein expression, with Bax translocation to the mitochondria. Furthermore, PA treatment induced mitochondrial impairment, and triggered the release of cytochrome c from the mitochondria to cytosol, with a concomitant dose-dependent increase in the levels of cleaved caspase-9, cleaved caspase-3, and PARP. Meanwhile, PA treatment increased mitochondrial production of ROS, and the mitochondria-targeted antioxidant mitoTEMPO significantly ameliorated PA-induced podocyte apoptosis. Conclusion: Our findings indicated that PA induced caspase-dependent podocyte apoptosis through the mitochondrial pathway, and mitochondrial ROS production participated in this process, thus potentially contributing to podocyte injury [ABSTRACT FROM AUTHOR]

Background/Aims: Periodic mechanical stress could significantly promote chondrocyte proliferation and matrix synthesis. However, the mechanisms underlying the ability of chondrocyte detecting and responding to periodic mechanical stimuli have not been well delineated. Methods: Quantitative proteomic analysis was performed to construct the differently expressed proteome profiles of chondrocyte under pressure. Then a combination of Western blot, quantitative real-time PCR, lentiviral vector and histological methods were used to confirm the proteomic results and investigate the mechanoseing mechanism. Results: Growth factor receptor-bound protein 2 (Grb2), a component of integrin adhesome, was found a 1.49-fold increase in dynamic stress group. This process was mediated through integrin β1, leading to increased phosphorylation of focal adhesion kinase (FAK) and extracellular signal-regulated kinase 1/2 (ERK1/2) respectively and then produce the corresponding biological effects. Conclusion: This was the first time to demonstrate Grb2 has such an important role in periodic mechanotransduction, and the proteomic data could facilitate the further investigation of chondrocytes mechanosensing. [ABSTRACT FROM AUTHOR]

Background/Aims: In recent years, a variety of studies have been performed to investigate the cellular responses of periodic mechanical stress. In our previous studies, we found that periodic mechanical stress can promote proliferation and matrix synthesis through the integrin beta 1-mediated ERK1/2 pathway, and we used proteomic analysis to detect quantitative changes in chondrocytes under periodic mechanical stress. Despite these results, the effects and mechanisms of periodic mechanical stress are still not fully understood, so in this study we extended our study using phosphoproteomic techniques. Methods: We used phosphoproteomic techniques to detect phosphorylation changes in chondrocytes under periodic mechanical stress and combined the results with the quantitative proteomic data to further explore the underlying mechanisms. Data were obtained by phosphorylation inhibition, quantitative real-time PCR (qPCR) analysis, western blot analysis and immunofluorescence assay. Results: From phosphoproteomic analysis, a total of 1073 phosphorylated proteins and 2054 phosphopeptides were identified. The number of significant differentially expressed proteins and phosphopeptides was 97 and 108, respectively (ratio >1.20 or <0.83 at p<0.05). Periodic mechanical stress increased glycogen synthase kinase 3-beta (GSK3-beta) phosphorylation at Y216, promoted the phosphorylation of beta-catenin, decreased betacatenin levels and suppressed the expression of type I collagen. In contrast, inhibition of GSK3-beta by TWS119, which specifically inhibits the phosphorylation of Y216, suppressed the phosphorylation of beta-catenin, which resulted in the accumulation of beta-catenin and an increase in the expression of type I collagen. Conclusions: We successfully constructed differentially expressed phosphoproteomic profiles of rat chondrocytes under periodic mechanical stress, and discovered a potential new therapeutic benefit in which periodic mechanical stress suppressed the formation of type I collagen in the matrix of chondrocytes via phosphorylation of GSK3-beta and beta-catenin. [ABSTRACT FROM AUTHOR]

Background/Aims: Periodic mechanical stress activates integrin β1-initiated signal pathways to promote chondrocyte proliferation and matrix synthesis. Integrin β1 overexpression has been demonstrated to play important roles in improving the activities and functions of several non-chondrocytic cell types. Therefore, in the current study, we evaluated the effects of integrin β1 up-regulation on periodic mechanical stress-induced chondrocyte proliferation, matrix synthesis and ERK1/2 phosphorylation in chondrocyte monolayer culture, and evaluated the quality of tissue-engineered cartilage constructed in vitro under periodic mechanical stress combined with integrin β1 up-regulation. Methods and Results: Our results revealed that under periodic mechanical stress, pre-treatment with integrin β1-wild type vector significantly enhanced chondrocyte proliferation and matrix synthesis and promoted ERK1/2 phosphorylation in comparison to mock transfectants. Furthermore, when chondrocytes were seeded in PLGA scaffolds, more accumulated GAG and type II collagen tissue were detected after Lv-integrin β1 transfection compared with sham controls exposed to periodic mechanical stress. In contrast, in the Lv-shRNA-integrin β1 group, the opposite results were observed. Conclusion: Our findings collectively suggest that in addition to periodic mechanical stress, integrin β1 up-regulation in chondrocytes could further improve the quality of tissue-engineered cartilage. © 2015 The Author(s) Published by S. Karger AG, Basel [ABSTRACT FROM AUTHOR]