A Prediction Model Based on the Risk Factors Associated with Pathological Upgrading in Patients with Early-Stage Gastric Neoplasms Diagnosed by Endoscopic Forceps Biopsy

Background/Aims@#The discrepancies between the diagnosis of preoperative endoscopic forceps biopsy (EFB) and endoscopic submucosal dissection (ESD) in patients with early gastric neoplasm (EGN) exist objectively. Among them, pathological upgrading directly influences the accuracy and appropriateness of clinical decisions. The aims of this study were to investigate the risk factors for the discrepancies, with a particular focus on pathological upgrading and to establish a prediction model for estimating the risk of pathological upgrading after EFB. @*Methods@#We retrospectively collected the records of 978 patients who underwent ESD from December 1, 2017 to July 31, 2021 and who had a final histopathology determination of EGN. A nomogram to predict the risk of pathological upgrading was constructed after analyzing subgroup differences among the 901 lesions enrolled. @*Results@#The ratio of pathological upgrading was 510 of 953 (53.5%). Clinical, laboratorial and endoscopic characteristics were analyzed using univariable and binary multivariable logistic regression analyses. A nomogram was constructed by including age, history of chronic atrophic gastritis, symptoms of digestive system, blood high density lipoprotein concentration, macroscopic type, pathological diagnosis of EFB, uneven surface, remarkable redness, and lesion size. The C-statistics were 0.804 (95% confidence interval, 0.774 to 0.834) and 0.748 (95% confidence interval, 0.664 to 0.832) in the training and validation set, respectively. We also built an online webserver based on the proposed nomogram for convenient clinical use. @*Conclusions@#The clinical value of identifying the preoperative diagnosis of EGN lesions is limited when using EFB separately. We have developed a nomogram that can predict the probability of pathological upgrading with good calibration and discrimination value.

Effects of high glucose exposure on permeability of brain microvascular endothelial cells / 上海预防医学

Objective To investigate the permeability of brain microvascular endothelial cells under the condition of high glucose exposure. Methods The bEnd.3 cell line was chosen to detect the value of trans- endothelial electrical resistance (TEER), the activity of alkaline phosphatase (ALP) and γ-glutamyl transferase (γ-GT).Hence, the characteristics of blood-brain barrier in cell model were identified.The permeability of brain microvascular endothelial cells on high glucose exposure was evaluated by cell morphology, cell viability, intracellular lactate dehydrogenase activity and relative expression of ZO-1 and Occludin genes. Results The value of TEER, the activity of ALP and γ-GT increased gradually with increasing incubation time.The observation of cell morphology showed that the number of cells decreased significantly under high glucose exposure, and the adherence was unstable.Cell viability decreased with higher concentration of glucose or longer exposure time under high glucose exposure.The activity of lactate dehydrogenase was also decreased, and there were significant differences among the dose groups (P < 0.05).In addition, the expression levels of tight junction protein ZO-1 and Occludin were further detected.It was found that high glucose exposure inhibited the expression of ZO-1 and Occludin genes in a dose-dependent manner. Conclusion The bEnd.3 cell line has the characteristics of blood-brain barrier.High glucose exposure inhibited the expression of tight junction protein ZO-1 and Occludin. The results might be related to the change of the permeability in brain microvascular endothelial cells

Effects of high glucose exposure on permeability of brain microvascular endothelial cells / 上海预防医学

Objective To investigate the permeability of brain microvascular endothelial cells under the condition of high glucose exposure. Methods The bEnd.3 cell line was chosen to detect the value of trans- endothelial electrical resistance (TEER), the activity of alkaline phosphatase (ALP) and γ-glutamyl transferase (γ-GT).Hence, the characteristics of blood-brain barrier in cell model were identified.The permeability of brain microvascular endothelial cells on high glucose exposure was evaluated by cell morphology, cell viability, intracellular lactate dehydrogenase activity and relative expression of ZO-1 and Occludin genes. Results The value of TEER, the activity of ALP and γ-GT increased gradually with increasing incubation time.The observation of cell morphology showed that the number of cells decreased significantly under high glucose exposure, and the adherence was unstable.Cell viability decreased with higher concentration of glucose or longer exposure time under high glucose exposure.The activity of lactate dehydrogenase was also decreased, and there were significant differences among the dose groups (P < 0.05).In addition, the expression levels of tight junction protein ZO-1 and Occludin were further detected.It was found that high glucose exposure inhibited the expression of ZO-1 and Occludin genes in a dose-dependent manner. Conclusion The bEnd.3 cell line has the characteristics of blood-brain barrier.High glucose exposure inhibited the expression of tight junction protein ZO-1 and Occludin. The results might be related to the change of the permeability in brain microvascular endothelial cells

Diagnostic value of acetic acid with narrow-band imaging and magnifying endoscopy for small colorectal polyps / 中华消化内镜杂志

Objective To evaluate the clinical value of acetic acid with narrow-band imaging ( NBI ) and magnifying endoscopy ( ME ) on diagnosis of small colorectal polyps. Methods In this prospective study, 261 small colorectal polyps from 122 patients were observed by ME, NBI-ME, and acetic acid with NBI-ME, and then received endoscopic treatment. Endoscopic images were stored electronically and randomly allocated to 3 experts and 3 non-experts for diagnosis using Kudo pit pattern. The postoperative pathologic results acted as gold standard to evaluate the diagnostic accuracy of different endoscopic modes for small colorectal polyps. The image definition and interobserver agreement were compared among different endoscopic modes. Results The diagnostic accuracy of ME, NBI-ME, and acetic acid with NBI-ME for small colorectal polyps was 65. 5％ ( 171/261) , 90. 0％ ( 235/261) , and 94. 6％ ( 247/261) , respectively, in the experts group, and 57. 1％ ( 149/261) , 83. 1％ ( 217/261) , and 89. 3％ ( 233/261) , respectively, in the non-experts group. All experts and non-experts diagnosed small colorectal polyps more accurately by acetic acid with NBI-ME than by NBI-ME ( all P<0. 05 ) and ME ( all P<0. 001 ) . The image definition scores of acetic acid with NBI-ME in the experts group and non-experts group were significantly higher than those of NBI-ME and ME ( all P<0. 001) . The results of interobserver agreement showed that Kappa values (95％CI) of ME, NBI-ME, and acetic acid with NBI-ME diagnosis were 0. 578 (0. 508-0. 648), 0. 669 (0. 599-0. 739), and 0. 940 (0. 870-1. 010), respectively, for experts and 0. 476 (0. 406-0. 546), 0. 534 ( 0. 464-0. 604) , and 0. 830 ( 0. 760-0. 900 ) , respectively, for non-experts. Acetic acid with NBI-ME showed good interobserver agreement. Conclusion Acetic acid with NBI-ME has a higher diagnostic accuracy and good reproducibility for colorectal small polyps compared with ME and NBI-ME.

Vav3, a GEF for RhoA, Plays a Critical Role under High Glucose Conditions

BACKGROUND: The role of small GTPase molecules is poorly understood under high glucose conditions. METHODS: We analyzed the expression pattern of Vav3 in skeletal muscle C2C12 cells under high glucose culture condition with reverse transcription-polymerase chain reaction and Western blot analysis. We also measured glucose uptake using isotope-labelled glucose. RESULTS: We showed that expression of Vav3 (a guanine nucleotide exchange factor for RhoA) increased. mRNA and protein levels in skeletal muscle C2C12 cells under high glucose conditions. The AMP-activated protein kinase (AMPK) activator AMPK agonist 5-aminoimidazole-4-carboxy-amide-1-d-ribofuranoside (AICAR) suppressed high glucose-induced Vav3 induction. In addition, exposure of cells to high glucose concentration increased the phosphorylation of PAK-1, a molecule downstream of RhoA. The phosphorylation of paxillin, a downstream molecule of PAK-1, was also increased by exposure to high glucose. Phosphorylation of these molecules was not observed in the presence of AICAR, indicating that AMPK is involved in the RhoA signal pathway under high glucose conditions. Knock down of Vav3 enhances metformin-mediated glucose uptake. Inhibition of AMPK blocked the increases of Vav3 knock down-induced glucose uptake. Metformin-mediated Glut4 translocation was also increased by Vav3 knock-down, suggesting that Vav3 is involved in metformin-mediated glucose uptake. CONCLUSION: These results demonstrate that Vav3 is involved in the process of metformin-mediated glucose regulation.

Tiam-1, a GEF for Rac1, plays a critical role in metformin-mediated glucose uptake in C2C12 cells.

Metformin is known to stimulate glucose uptake, but the mechanism for this action is not fully understood. In this study, AMPK activators (AICAR and metformin) increased the expression of T-lymphoma invasion and metastasis-inducing protein-1 (Tiam-1), a Rac1 specific guanine nucleotide exchange factor (GEF), mRNA and protein in skeletal muscle C2C12 cells. Metformin increases the serine-phosphorylation of Tiam-1 by AMPK and induces interaction between Tiam-1 and 14-3-3. Pharmacologic inhibition of AMPK blocks this interaction, indicating that 14-3-3 may be required for induction of Tiam-1 by AMPK. Metformin also increases the phosphorylation of p21-activated kinase 1 (PAK1), a direct downstream target of Rac1, dependent on AMPK. Tiam-1 is down-regulated at high glucose concentrations in cultured cells and in the db/db mouse model of hyperglycemia. Furthermore, Tiam-1 knock-down blocked metformin-induced increase in glucose uptake. These findings suggest that metformin promotes cellular glucose uptake in part through Tiam-1 induction.

E3 ubiquitin ligase, WWP1, interacts with AMPKα2 and down-regulates its expression in skeletal muscle C2C12 cells.

It is known that the activity of AMP-activated protein kinase (AMPKα2) was depressed under high glucose conditions. However, whether protein expression of AMPKα2 is also down-regulated or not remains unclear. In this study, we showed that the expression of AMPKα2 was down-regulated in cells cultured under high glucose conditions. Treatment of proteasome inhibitor, MG132, blocked high glucose-induced AMPKα2 down-regulation. Endogenous AMPKα2 ubiquitination was detected by immunoprecipitation of AMPKα2 followed by immunoblotting detection of ubiquitin. The yeast-two hybrid (YTH) approach identified WWP1, an E3 ubiquitin ligase, as the AMPKα2-interacting protein in skeletal muscle cells. Interaction between AMPKα2 and WWP1 was validated by co-immunoprecipitation. Knockdown of WWP1 blocked high glucose-induced AMPKα2 down-regulation. The overexpression of WWP1 down-regulated AMPKα2. In addition, the expression of WWP1 is increased under high glucose culture conditions in both mRNA and protein levels. The level of AMPKα2 was down-regulated in the quadriceps muscle of diabetic animal model db/db mice. Expression of WWP1 blocked metformin-induced glucose uptake. Taken together, our results demonstrated that WWP1 down-regulated AMPKα2 under high glucose culture conditions via the ubiquitin-proteasome pathway.