Objective:To explore the effect of cathepsin L (CTSL) inhibitor on apoptosis of retinal pigment epithelial (RPE) cells and mitochondrial oxidative stress.Methods:RPE cells were cultured in vitro and divided into control group, hydrogen peroxide (H 2O 2) group, and H 2O 2+CTSL inhibitor group. The cells of H 2O 2 group and H 2O 2+CTSL inhibitor group were incubated in the medium containing 400 μmol/L H 2O 2 for 24 hours and 10 μmol/L CTSL inhibitor was added in H 2O 2+CTSL inhibitor group at the same time. The cells of normal group were routinely cultured cells. The follow-up experiment was carried out 24 hours after modeling. The rate of apoptosis was detected by flow cytometry. The expression of CTSL was detected by immunofluorescence staining, Western blot and real time-polymerase chain reaction. The level of mitochondrial super oxide was detected by MitoSOX fluorescent probe, and the mitochondrial structure was observed after MitoTracker staining, the average area, form factors, and branch of mitochondria were quantitatively analyzed. The two groups were compared using two-tailed Student t test, while numerous groups were compared using one-way ANOVA. Results:Compared with control group, the rate of apoptosis in H 2O 2 group was significantly higher ( t=3.307, P=0.029 7), the expression level of CTSL was significantly increased ( t=19.950, 6.916, 14.220; P<0.05). Compared with H 2O 2 group, the expression level of CTSL, the rate of apoptosis and the mitochondrial ROS level in H 2O 2+CTSL inhibitor group were significantly lower ( t=11.940, 4.718, 16.680; P<0.05). The mitochondria of H 2O 2+CTSL inhibitor group were elongated, oval-shaped or rod-shaped, while the mitochondria of H 2O 2 group lost their continuous contour shape and complete structure. The differences of the average area, form factors, and brach of mitochondria among 4 groups were statistically significant ( F=251.700, 34.010, 60.500; P<0.000 1). Conclusions:H 2O 2 can significantly induce apoptosis in RPE cells and increase CTSL expression. CTSL inhibitor can inhibit the H 2O 2-induced apoptosis of RPE cells, lower the mitochondrial super oxide level, and successfully repair the mitochondrial structure.

Objective:To observe the effects of NDRG1 on proliferation, migration and lumen formation of retinal vascular endothelial cells (RF/6A cells) in monkeys under high glucose condition. Methods:RF/6A cells were divided into normal group, mannitol group, high glucose group, small interfering RNA (siRNA) negative control group without target gene (siRNA group), 30 nmol/L siRNA down-regulated NDRG1 genome (siNDRG1 group) and 50 nmol/L siNDRG1 group. Normal group cells were cultured conventionally. The mannitol group was added with 25 mmol/L mannitol, and the high-glucose group was added with 25 mmol/L glucose. In the siRNA group, 25 mmol/L glucose was added, and then blank siRNA was added for induction. The 30 and 50 nmol/L siNDRG1 groups were added with 25 mmol/L glucose and induced with 30 and 50 nmol/L siRNDRG1, respectively. All cells were incubated for 24 h for follow-up experiments. Cell proliferation was observed by 4', 6-diaminidine 2-phenylindole staining. Cell counting kit-8 staining was used to detect cell activity. The expression level of NDRG1 mRNA and protein was detected by Western blot and real-time quantitative polymerase chain reaction. Cell migration was observed by cell scratch assay. Cell lumen formation assay was used to detect lumen formation. The two-tailed Student t test was used to compare the two groups. One-way analysis of variance was used to compare groups. Results:There were significant differences in cell proliferation rate ( t=36.659, 57.645) mobility rate ( t=24.745, 33.638) and lumen formation number ( t=41.276, 22.867) between high glucose group and normal group and mannitol group ( P <0.01). Compared with normal group and mannitol group, the relative expression levels of NDRG1 gene mRNA and protein in high glucose group were significantly decreased, with statistical significance ( t=46.145, 21.541, 36.738, 32.976; P<0.001). Compared with the siRNA negative group, the relative expression levels of NDRG1 gene mRNA and protein in 30 nmol/L siNDRG1 group and 50 nmol/L siNDRG1 group were significantly decreased, and the differences were statistically significant ( t=44.275, 40.7577, 57.167, 25.877; P<0.01). Compared with normal group and siRNA group, cell mobility in 30 nmol/LsiNDRG1 group was increased, and the difference was statistically significant ( t=57.562, 49.522; P<0.01). Compared with normal group and siRNA group, the number of cell lumen formation in 30 nmol/LsiNDRG1 group was significantly increased in the same field of vision, and the difference was statistically significant ( t=63.446, 42.742; P<0.01). Conclusion:Down-regulation of NDRG1 gene can improve the activity, migration and lumen formation of RF/6A cells under hyperglycemia.

Objective:To observe the effect of Nodal on the biological behavior of retinal vascular endothelial cells (RF/6A cells) in monkeys with high glucose.Methods:RF/6A cells were divided into normal group, mannitol group, high glucose group, high glucose combined with non-specific small interfering RNA treatment group (HG+NC group), high glucose combined with small interfering Nodal treatment group (HG+siNodal group). The transfection efficiency of siNodal was observed by real-time fluorescence quantitative PCR and western blot protein immunoblotting. The effect of Nodal on the proliferation of RF/6A cells was detected by thiazole blue colorimetry. The effect of Nodal on migration ability of RF/6A cells was detected by cell scratch assay. The effect of Nodal on the formation of RF/6A cell lumen was measured by Matrigel three-dimensional in vitro. The expression of extracellular signal phosphorylated regulated kinase 1/2 (pERK1/2) in RF/6A cells was detected by western blot protein immunoblotting. One-way analysis of variance was used to compare groups.Results:Compared with HG+NC group, Nodal protein ( F=33.469) and mRNA relative expression levels ( F=38.191) in HG+siNodal group were significantly decreased, cell proliferation was significantly decreased ( F=28.548), and cell migration ability was significantly decreased ( F=24.182). The number of cell lumen formation was significantly decreased ( F=52.643), and the differences were statistically significant ( P<0.05). Compared with HG+NC group, the relative expression of pERK1/2 protein in HG+siNodal group was significantly decreased, and the difference was statistically significant ( F=44.462, P<0.01). Conclusions:Silencing Nodal expression can inhibit proliferation, migration and tube formation of RF/6A cells induced by high glucose. It may act by inhibiting pERK1/2 expression.

Purpose: Neoadjuvant chemotherapy is strongly recommended for advanced gastric cancer due to good local control and a high rate of R0 dissection with this strategy. Minimally invasive techniques such as laparoscopy-assisted or total laparoscopic approaches is becoming more and more acceptable in the treatment for gastric cancer. However, the safety and efficiency of total laparoscopic D2 gastrectomy (TLG) for advanced gastric cancer after neoadjuvant chemotherapy have not been well evaluated. Methods: A retrospective study in a single center from 2014 to 2016 was conducted. A total of 65 locally advanced gastric cancers were treated by laparoscopy-assisted gastrectomy (LAG) or TLG. Parameters which include operation time, blood loss, complications, hospital stay, 3-year overall survival, and 3-year disease-free survival were used for comparison. Results: The time of operation in the TLG group was shorter than in the LAG group (P = 0.013), blood loss was less (P = 0.002) and time to first flatus was shorter (P = 0.039) in the TLG group than that in the LLG group. Intraoperative and postoperative complications were comparable in both groups. No significant difference was found in 3-year overall and disease-free survival. Conclusion For patients with locally advanced gastric cancer after neoadjuvant chemotherapy, laparoscopic D2 gastrectomy can be considered as a safe and efficient alternative. A further multicenter prospective randomized controlled study is needed to elucidate the applicability of this technique for advanced gastric cancer.

Objective:To observe the effect of high expression of polypyrimidine tract-binding protein-associated splicing factor (PSF) on low concentration of 4-hydroxynonenal (4-HNE) induced human retinal microvascular endothelial cells (HRMECs), and explore the possible mechanism.Methods:The HRMECs cultured in vitro were divided into 4-HNE treated group, PSF overexpression group combined with 4-HNE group (PSF+4-HNE group), PSF overexpression+ML385 treatment combined with 4-HNE group (PSF+ML385+4-HNE group), and 4-HNE induced PSF overexpression group with LY294002 pretreatment (LY294002+4-HNE+PSF group). Cell culture medium containing 10 μmmol/L 4-HNE was added into 4-HNE treatment group, PSF+4-HNE group, PSF+ML385+4-HNE group for 12 hours to stimulate oxidative stress. 1.0 μg of pcDNA-PSF eukaryotic expression plasmid were transfected into PSF+4-HNE group and PSF+ML385+4-HNE group to achieve the overexpression of PSF. Also cells were pretreated with ML385 (5 μmol/L) for 48 hours in the PSF+ML385+4-HNE group, meanwhile within the LY294002+4-HNE+PSF group, after pretreatment with LY294002, cells were treated with plasmid transfection and 4-HNE induction. Transwell detects the migration ability of PSF to HRMECs. The effect of PSF on the lumen formation of HRMECs was detected by using Matrigel in vitro three-dimensional molding method. Flow cytometer was used to detect the effect of PSF overexpression on reactive oxygen (ROS) level in HRMECs. Protein immunoblotting was used to detect the relative expression of PSF, nuclear factor E2 related factor 2 (Nrf2), heme oxygenase-1 (HO-1) protein, and phosphoserine threonine protein kinase (pAkt) protein. The comparison between the two groups was performed using a t-test. Results:The number of live cells, migrating cells, and intact lumen formation in the 4-HNE treatment group and the PSF+4-HNE group were 1.70±0.06, 0.80±0.13, 24.00±0.58, 10.00±0.67, and 725.00±5.77, 318.7±12.13, respectively. There were significant differences in the number of live cells, migrating cells, and intact lumen formation between the two groups ( t=12.311, 15.643, 17.346; P<0.001). The results of flow cytometry showed that the ROS levels in the 4-HNE treatment group, PSF+4-HNE group, and PSF+ML385+4-HNE group were 816.70±16.67, 416.70±15.44, and 783.30±17.41, respectively. There were statistically significant differences between the two groups ( t=16.311, 14.833, 18.442; P<0.001). Western blot analysis showed that the relative expression levels of pAkt, Nrf2, and HO-1 proteins in HRMECs in the 4-HNE treatment group, PSF+4-HNE group and LY294002+4-HNE+PSF group were 0.08±0.01, 0.57±0.04, 0.35±0.09, 0.17±0.03, 1.10±0.06, 0.08±0.11 and 0.80±0.14, 2.50±0.07, 0.50±0.05, respectively. Compared with the PSF+4-HNE group, the relative expression of pAkt, Nrf2, and HO-1 proteins in the LY294002+4-HNE+PSF group decreased significantly, with significant differences ( t=17.342, 16.813, 18.794; P<0.001). Conclusion:PSF upregulates the expression of HO-1 by activating the phosphatidylinositol 3 kinase/Akt pathway and inhibits cell proliferation, migration, and lumen formation induced by low concentrations of 4-HNE.

Objective:To observe the effects of p21 activated kinase 4 (PAK4) on the mitochondrial function and biological behavior in retinal vascular endothelial cells.Methods:The experimental study was divided into two parts: in vivo animal experiment and in vitro cell experiment. In vivo animal experiments: 12 healthy C57BL/6J male mice were randomly divided into normal control group and diabetes group, with 6 mice in each group. Diabetes mice were induced by streptozotocin to establish diabetes model. Eight weeks after modeling, quantitative real-time polymerase chain reaction and Western blots were performed to detect the expression of PAK4 in diabetic retinas. In vitro cell experiments: the human retinal microvascular endothelial cells (hRMEC) were divided into three groups: conventional cultured cells group (N group), empty vector transfected (Vector group); pcDNA-PAK4 eukaryotic expression plasmid transfected group (PAK4 group). WB and qPCR were used to detect transfection efficiency, while scratching assay, cell scratch test was used to detect cell migration in hRMEC of each group. In vitro white blood cell adhesion experiment combined with 4 ', 6-diamino-2-phenylindole staining was used to detect the number of white blood cells adhering to hRMEC in each group. The Seahorse XFe96 cell energy metabolism analyzer measures intracellular mitochondrial basal respiration, adenosine triphosphate (ATP) production, maximum respiration, and reserve respiration capacity. The t-test was used for comparison between the two groups. Single factor analysis of variance was used for comparison among the three groups. Results:In vivo animal experiments: compared with normal control group, the relative expression levels of PAK4 mRNA and protein in retina of diabetic mice were significantly increased, with statistical significance ( t=25.372, 22.419, 25.372; P<0.05). In vitro cell experiment: compared with the N group and Vector group, the PAK4 protein, mRNA relative expression and cell mobility in the hRMEC of PAK4 group were significantly increased, with statistical significance ( F=36.821, 38.692, 29.421; P<0.05). Flow cytometry showed that the adhesion number of leukocytes on hRMEC in PAK4 group was significantly increased, and the difference was statistically significant ( F=39.649, P<0.01). Mitochondrial pressure measurement results showed that the capacity of mitochondrial basic respiration, ATP production, maximum respiration and reserve respiration in hRMEC in PAK4 group was significantly decreased, with statistical significance ( F=27.472, 22.315, 31.147, 27.472; P<0.05). Conclusion:Over-expression of PAK4 impairs mitochondrial function and significantly promotes leukocyte adhesion and migration in retinal vascular endothelial cells.

Objective:To observe the effect of metformin (Met) on inflammatory bodies and focal death in human retinal microvascular endothelial cells (hRMEC) in diabetes mellitus (DM) microenvironment.Methods:Experimental research was divided into in vivo animal experiment and in vitro cell experiment. In vivo animal experiments: 9 healthy C57BL/6J male mice were randomly divided into DM group, normal control group, and DM+Met group, with 3 mice in each group. DM group and DM+Met group mice were induced by streptozotocin to establish DM model, and DM+Met group was given Met 400 mg/ (kg · d) intervention. Eight weeks after modeling, the expression of NLRP3, cleaved-membrane perforating protein D (GSDMD) and cleaved-Caspase-1 in the retina of mice in the normal control group, DM group and DM+Met group were observed by immunohistochemical staining. In vitro cell experiments: hRMEC was divided into conventional culture cell group (N group), advanced glycation end products (AGE) group, and AGE+Met group. Joining the AGE, AGE+Met groups cells were induced by 150 μg/ml of glycation end products, and 2.0 mmol/L Met was added to the AGE+Met group. Pyroptosis was detected by flow cytometry; 2' ,7'-dichlorofluorescein diacetate (DCFH-DA) fluorescent probe was used to detect the expression of reactive oxygen species (ROS) in cells of each group. Real-time fluorescence quantitative polymerase chain reaction and Western blot were used to detect the relative mRNA and protein expression levels of NLRP3, cleaved-GSDMD, cleaved-Caspase-1 in each group of cells. Single factor analysis of variance was used for comparison among the three groups.Results:In vivo animal experiments: compared with the DM group, the expression of NLRP3, cleaved-GSDMD, and cleaved-Caspase-1 in the retina of normal control group and DM+Met group mice was significantly reduced, with significant difference among the 3 groups ( F=43.478, 36.643, 24.464; P<0.01). In vitro cell experiment and flow cytometry showed that the pyroptosis rate of AGE group was significantly higher than that of N group and AGE+Met group ( F=32.598, P<0.01). The DCFH-DA detection results showed that the intracellular ROS levels in the N group and AGE+Met group were significantly lower than those in the AGE group, with the significant difference ( F=47.267, P<0.01). The mRNA ( F=51.563, 32.192, 44.473; P<0.01) and protein levels ( F=63.372, 54.463, 48.412; P<0.01) of NLRP3, cleaved-GSDMD, and cleaved-Caspase-1 in hRMEC of the AGE+Met group were significantly reduced compared to the N group. Conclusion:Met can down regulate the expression of NLRP3 inflammatory body related factors in hRMEC and inhibit pyroptosis.

Objective:To observe the effects of overexpression of polypyrimidine tract binding protein-associated splicing factor (PSF) on the endoplasmic reticulum (ER) oxidative stress damage of human retinal microvascular endothelial cells (hRMEC) under high concentration of 4-hydroxynonenal (4-HNE).Methods:The logarithmic growth phase hRMEC cultured in vitro was divided into normal group, simple 4-HNE treatment group (simple 4-HNE group), empty plasmid combined with 4-HNE treatment group (Vec+4-HNE group), and PSF high expression combined with 4-HNE treatment group (PSF+4-HNE group). In 4-HNE group, Vec+4-HNE group, and PSF+4-HNE group cell culture medium, 10 μmol/L 4-HNE was added and stimulated for 12 hours. Subsequently, the Vec+4-HNE group and PSF+4-HNE group were transfected with transfection reagent liposome 2000 into pcDNA empty bodies and pcDNA-PSF eukaryotic expression plasmids, respectively, for 24 hours. Flow cytometry was used to detect the effects of 4-HNE and PSF on cell apoptosis. The effect of PSF overexpression on the expression of reactive oxygen species (ROS) in hRMEC was detected by 2', 7'-dichlorodihydrofluorescein double Acetate probe. Western blot was used to detect ER oxide protein 1 (Ero-1), protein disulfide isomerase (PDI), C/EBP homologous transcription factor (CHOP), glucose regulatory protein (GRP) 78, protein kinase R-like ER kinase (PERK)/phosphorylated PERK (p-PERK), and Eukaryotic initiation factor (eIF) 2α/the relative expression levels of phosphorylated eIF (peIF) and activated transcription factor 4 (ATF4) proteins in hRMEC of normal group, 4-HNE group, Vec+4-HNE group, and PSF+4-HNE group. Single factor analysis of variance was performed for inter group comparison.Results:The apoptosis rates of the simple 4-HNE group, Vec+4-HNE group, and PSF+4-HNE group were (22.50±0.58)%, (26.93±0.55)%, and (11.70±0.17)%, respectively. The intracellular ROS expression levels were 0.23±0.03, 1.60±0.06, and 0.50±0.06, respectively. The difference in cell apoptosis rate among the three groups was statistically significant ( F=24.531, P<0.05). The expression level of ROS in the Vec+4-HNE group was significantly higher than that in the simple 4-HNE group and the PSF+4-HNE group, with a statistically significant difference ( F=37.274, P<0.05). The relative expression levels of ER Ero-1 and PDI proteins in the normal group, simple 4-HNE group, Vec+4-HNE group, and PSF+4-HNE group were 1.25±0.03, 0.45±0.03, 0.63±0.03, 1.13±0.09, and 1.00±0.10, 0.27±0.10, 0.31±0.05, and 0.80±0.06, respectively. The relative expression levels of CHOP and GRP78 proteins were 0.55±0.06, 1.13±0.09, 0.90±0.06, 0.48±0.04 and 0.48±0.04, 1.25±0.03, 1.03±0.09, 0.50±0.06, respectively. The relative expression levels of Ero-1 ( F=43.164), PDI ( F=36.643), CHOP ( F=42.855), and GRP78 ( F=45.275) proteins in four groups were compared, and the differences were statistically significant ( P<0.05). Four groups of cells ER p-pERK/pERK ( F=35.755), peIF2 α/ The relative expression levels of eIF ( F=38.643) and ATF4 ( F=31.275) proteins were compared, and the differences were statistically significant ( P<0.05). Conclusion:PSF can inhibit cell apoptosis and ROS production induced by high concentration of 4-HNE, and its mechanism is closely related to restoring the homeostasis of ER and down-regulating the activation level of PERK/eIF2α/ATF4 pathway.

Enterotoxigenic Escherichia coli（ETEC）infection can induce watery diarrhea，leading to dehydration，electrolyte disturbance，and even death in severe cases. Recombinant B subunit/inactivated whole-cell cholera（rBS/WC）vaccine is effective in preventing ETEC infectious diarrhea. On the basis of the latest evidence on etiology and epidemiology of ETEC，as well as the effectiveness，safety，and health economics of rBS/WC vaccine，National Clinical Research Center for Child Health（The Children’s Hospital，Zhejiang University School of Medicine）and Zhejiang Provincial Center for Disease Control and Prevention invited experts to develop expert consensus on rBS/WC vaccine in prevention of ETEC infectious diarrhea. It aims to provide the clinicians and vaccination professionals with guidelines on using rBS/WC vaccine to reduce the incidence of ETEC infectious diarrhea.

Objective:To investigate the effects of targeted regulation of SMAD9 expression by bone morphogenetic protein 4 (BMP4) on Müller cell migration, reactive oxygen species (ROS) generation and vascular endothelial growth factor (VEGF) expression.Methods:Müller cells cultured in vitro were divided into normal control group, BMP4 group, BMP4+ no-load plasmid group (BMP4+NC group) and BMP4+SMAD9 small interference plasmid group (BMP4+siSMAD9). Cells in BMP4 group, BMP4+NC group and BMP4+siSMAD9 group were induced by adding 100 ng/ml BMP4 into cell medium for 24 h. Subsequently, BMP4+NC group was transfected with empty plasmid. BMP4+siSMAD9 group was transfected with SMAD9 small interference plasmid for 48 h. The effect of BMP4 on Müller cell migration was determined by cell scratch test. The effect of BMP4 on the production of ROS in Müller cells was detected by flow cytometry. Western blots and real-time quantitative fluorescence polymerase chain reaction (qPCR) were used to detect the relative mRNA expression levels of glutamine synthetase (GS) and glial fibrinoacidic protein (GFAP) in Müller cells. VEGF expression in Müller cells was detected by immunofluorescence. One-way analysis of variance was used to compare groups.Results:The results of cell scratch test showed that the cell mobility of BMP4+siSMAD9 group was significantly lower than that of BMP4 and BMP4+NC group, and the difference was statistically significant ( F=68.319, P<0.001). Flow cytomethods showed that the level of ROS in BMP4+siSMAD9 group was significantly lower than that in BMP4 and BMP4+NC group, and the difference was statistically significant ( F=52.158, P<0.001). Western blot and qPCR results showed that the protein levels of GS and GFAP ( F=42.715, 36.618) and mRNA relative expression levels ( F=45.164, 43.165) in BMP4+siSMAD9 group were significantly lower than those in BMP4 and BMP4+NC group. The difference was statistically significant ( P<0.01). The results of immunofluorescence detection showed that the intracellular VEGF fluorescence intensity in BMP4 group and BMP4+NC group was significantly higher than that in BMP4+siSMAD9 group, and the difference was statistically significant ( F=46.384, P<0.05). Conclusion:Targeted regulation of SMAD9 expression by BMP4 can up-regulate VEGF expression and promote the migration and ROS production of Müller cells.