Feasibility and efficacy of endoscopic purse-string suture-assisted closure for mucosal defects induced by endoscopic manipulations.

BACKGROUND: Large or transmural defects induced by gastrointestinal endoscopic manipulations are difficult to close, although complete closure is recommended for better recovery. Endoscopic purse-string assisted suturing (EPSS) has been used in clinical practice and has proven to be an effective and safe technique for the closure of large mucosal defects. However, details regarding the efficacy of endoscopic pre-purse-string suture (P-EPSS) are unknown, especially that it offers several advantages over conventional EPSS (C-EPSS). AIM: To elucidate the outcomes of EPSS-assisted closure in different clinical situations, and evaluate the efficacy of P-EPSS. METHODS: This retrospective observational study included a total of 180 patients who underwent closure assisted by P-EPSS (n = 63) or C-EPSS (n = 117) between July 2014 and June 2020. The P-EPSS and C-EPSS groups were compared and the intergroup differences in aspects such as the lesion size, location, and mor-phology, incidence of complete closure, intraoperative perforation, and delayed adverse events were evaluated. Data on the features and clinical course of cases with adverse events were collected for further analysis. RESULTS: Patients with lesion size larger than 3 cm, lesions located at the fundus of stomach, or submucosal tumors originating from the deep mucosa were more likely to undergo P-EPSS-assisted closure. The P-EPSS group showed a sign-ificantly higher proportion of intraoperative perforation (56% vs 17%) and a much shorter procedure time (9.06 ± 6.14 min vs 14.84 ± 7.25 min). Among adverse events, the incidence of delayed perforation (5% vs 4%; P = 0.82) and delayed bleeding (3% vs 4%; P = 0.96) did not differ significantly between the groups. Multivariate analysis revealed that lesions with incomplete closure [odds ratio (OR) = 21.33; 95% confidence interval (CI): 5.45-83.45; P < 0.01] or size greater than 3 cm (OR = 3.14; 95%CI: 1.08-9.18; P = 0.039) showed a statistical tendency to result in an increase in delayed adverse events. CONCLUSION: The present study revealed that EPSS could achieve secure complete closure of mucosal defect. P-EPSS could shorten the procedure and yield complete closure of mucosal defects. Rather than closure-type selection, incomplete closure or lesion size larger than 3 cm were associated with worse outcomes.

Potential factors affecting success rate and long term outcome in single balloon enteroscopy-assisted therapeutic endoscopic retrograde cholangiopancreatography in patients with pancreaticojejunal anastomotic stenosis: a retrospective study.

Background: Pancreaticojejunal anastomotic stenosis (PJS) after pancreaticoduodenectomy (PD) is difficult to treat. Single-balloon enteroscope-assisted endoscopic retrograde pancreatography (SBE-assisted ERP) is a safe way to treat PJS with the strength of minimally invasion and repeatability, but since its technical difficulty and few patient number, data on long-term outcomes remain limited. The optimal treatment is still unknown. We aim to study the safety, effectiveness, and long-term outcome of single balloon enteroscopy-assisted (SBE-assisted) therapeutic ERP in patients with PJS in this study. Methods: The clinical information of patients undergoing SBE-assisted therapeutic ERP from March 2016 to March 2021 were retrospectively analyzed. All patients were diagnosed as PJS and without any contraindication for therapeutic endoscopy. Treatment details, postoperative complications, factors influencing technical success rate were evaluated. Long-term outcomes results were obtained by clinical or telephone follow-up. Results: Sixteen patients with median age of 51 years were included in this study, surgical reconstruction methods including PD with Whipple reconstruction, PD with Child reconstruction, pylorus-preserving pancreaticoduodenectomy (PpPD) with Whipple reconstruction. Eight patients were successfully treated. No serious complications happened. Risk factors for the failure of pancreaticojejunal anastomotic site identification include the digestive tract reconstruction sequence, pancreaticojejunostomy method, pancreatic duct tube implantation, pancreatic duct width before surgery, and pancreatic fistula during perioperative period. The median follow-up time was 77.2 months, the mean indwelling time of the stent was 62.3 months [interquartile range (IQR), 6.8-153.7 months]. Two of eight patients developed recurrent PJS. The variation in body mass index (BMI) was +2.46 in the non-recurrence group compared to -1.09 in the recurrence group and -2.12 in the endoscopic retrograde cholangiopancreatography (ERCP) treatment failure group. Conclusions: ERP intervention should be carried out early once PJS occurs in order to increase success rate. BMI is a crucial indicator which can reflex PJS rehabilitation degree during follow-up. In order to reduce PJS recurrence rate, a wider pancreatic stent and a longer stent indwelling time are recommended.

Combining protein arginine methyltransferase inhibitor and anti-programmed death-ligand-1 inhibits pancreatic cancer progression.

BACKGROUND: Immunotherapy targeting programmed death-1 (PD-1) or programmed death-ligand-1 (PD-L1) has been shown to be effective in a variety of malignancies but has poor efficacy in pancreatic ductal adenocarcinoma (PDAC). Studies have shown that PD-L1 expression in tumors is an important indicator of the efficacy of immunotherapy. Tumor cells usually evade chemotherapy and host immune surveillance by epigenetic changes. Protein arginine methylation is a common posttranslational modification. Protein arginine methyltransferase (PRMT) 1 is deregulated in a wide variety of cancer types, whose biological role in tumor immunity is undefined. AIM: To investigate the combined effects and underlying mechanisms of anti-PD-L1 and type I PRMT inhibitor in pancreatic cancer in vivo. METHODS: PT1001B is a novel type I PRMT inhibitor with strong activity and good selectivity. A mouse model of subcutaneous Panc02-derived tumors was used to evaluate drug efficacy, toxic and side effects, and tumor growth in vivo. By flow cytometry, we determined the expression of key immune checkpoint proteins, detected the apoptosis in tumor tissues, and analyzed the immune cells. Immunohistochemistry staining for cellular proliferation-associated nuclear protein Ki67, TUNEL assay, and PRMT1/PD-L1 immunofluorescence were used to elucidate the underlying molecular mechanism of the antitumor effect. RESULTS: Cultured Panc02 cells did not express PD-L1 in vitro, but tumor cells derived from Panc02 transplanted tumors expressed PD-L1. The therapeutic efficacy of anti-PD-L1 mAb was significantly enhanced by the addition of PT1001B as measured by tumor volume (1054.00 ± 61.37 mm3 vs 555.80 ± 74.42 mm3, P < 0.01) and tumor weight (0.83 ± 0.06 g vs 0.38 ± 0.02 g, P < 0.05). PT1001B improved antitumor immunity by inhibiting PD-L1 expression on tumor cells (32.74% ± 5.89% vs 17.95% ± 1.92%, P < 0.05). The combination therapy upregulated tumor-infiltrating CD8+ T lymphocytes (23.75% ± 3.20% vs 73.34% ± 4.35%, P < 0.01) and decreased PD-1+ leukocytes (35.77% ± 3.30% vs 6.48% ± 1.08%, P < 0.001) in tumor tissue compared to the control. In addition, PT1001B amplified the inhibitory effect of anti-PD-L1 on tumor cell proliferation and enhanced the induction of tumor cell apoptosis. PRMT1 downregulation was correlated with PD-L1 downregulation. CONCLUSION: PT1001B enhances antitumor immunity and combining it with anti-PD-L1 checkpoint inhibitors provides a potential strategy to overcome anti-PD-L1 resistance in PDAC.

Preliminary study on the inhibitory effect of tumor suppressor gene KPC1 on the proliferation in gastric carcinoma cell.

BACKGROUND: To investigate Kip1 ubiquitination-promoting complex 1 (KPC1) expression and its relationship with NF-κB p50 in gastric cancer cell lines. METHODS: The expression of KPC1 and NF-κB p50 in tissue samples from 159 gastric cancer patients after tumor resection and normal gastric mucosa samples from 56 patients as negative controls was retrospectively studied. The relationship between KPC1, NF-κB p50, and clinicopathological factors was analyzed, and the correlation between KPC1 and cytoplasmic NF-κB p50 was determined. The expression level of KPC1 and NF-κB p50 was researched using reverse transcription (RT) polymerase chain reaction (RT-PCR) and Western blotting in 3 differentiated human gastric cancer cell lines (AGS, SGC-7901 and MGC-803). RESULTS: Immunohistochemistry indicated that KPC1 and NF-κB p50 expression was significantly decreased in gastric cancer cases, and the level of expression varied across the differentiated gastric cancer tissues. KPC1 and NF-κB p50 expression was significantly connected with tumor differentiation, tumor-node-metastasis (TNM) staging, and metastasis of 159 patients suffering from gastric cancer (P<0.05), but not correlated with age and lesion size (P>0.05). KPC1 was positively connected with the expression of NF-κB p50 by the Spearman correlation analysis (r=0.427, P<0.05). The expression of KPC1 and NF-κB p50 mRNA was reduced, and there were differences in the 3 differentiated human gastric cancer cell lines, as confirmed by western blotting. CONCLUSIONS: The co-expression of KPC1 and cytoplasmic NF-κB p50 in gastric cancer promotes tumor suppressor gene expression. Therefore, limiting the growth of tumor cells may inhibit the development of gastric cancer.

Application of single balloon enteroscopy-assisted therapeutic endoscopic retrograde cholangiopancreatography in patients after bilioenteric Roux-en-Y anastomosis: Experience of multi-disciplinary collaboration.

BACKGROUND: Bilioenteric Roux-en-Y anastomosis is one of the most complicated approaches for reconstructing the gastrointestinal tract, and endoscopic retrograde cholangiopancreatography (ERCP) is technically challenging in patients after bilioenteric Roux-en-Y anastomosis. The optimal endoscopic strategies for such cases remain unknown. AIM: To explore the feasibility and effectiveness of single balloon enteroscopy-assisted (SBE-assisted) therapeutic ERCP in patients after bilioenteric Roux-en-Y anastomosis based on multi-disciplinary collaboration between endoscopists and surgeons as well as report the experience from China. METHODS: This is a single center retrospective study. All of the SBE-assisted therapeutic ERCP procedures were performed by the collaboration between endoscopists and surgeons. The operation time, success rate, and complication rate were calculated. RESULTS: Forty-six patients received a total of 64 SBE-assisted therapeutic ERCP procedures, with successful scope intubation in 60 (93.8%) cases and successful diagnosis in 59 (92.2%). All successfully diagnosed cases received successful therapy. None of the cases had perforation or bleeding during or after operation, and no post-ERCP pancreatitis occurred. CONCLUSION: Based on multi-disciplinary collaboration, SBE-assisted therapeutic ERCP in patients after bilioenteric Roux-en-Y anastomosis is relatively safe and effective and has a high success rate.

Effect of photodynamic therapy with (17R,18R)-2-(1-hexyloxyethyl)-2-devinyl chlorine E6 trisodium salt on pancreatic cancer cells in vitro and in vivo.

AIM: To investigate the antitumor effects and underlying mechanisms of (17R,18R)-2-(1-hexyloxyethyl)-2-devinyl chlorine E6 trisodium salt (YLG-1)-induced photodynamic therapy (PDT) on pancreatic cancer in vitro and in vivo. METHODS: YLG-1 is a novel photosensitizer extracted from spirulina. Its phototoxicity, cellular uptake and localization, as well as its effect on reactive oxygen species (ROS) production, apoptosis, and expression of apoptosis-associated proteins were detected in vitro. An in vivo imaging system (IVIS), the Lumina K imaging system, and mouse models of subcutaneous Panc-1-bearing tumors were exploited to evaluate the drug delivery pathway and pancreatic cancer growth in vivo. RESULTS: YLG-1 was localized to the mitochondria, and the appropriate incubation time was 6 h. Under 650 nm light irradiation, YLG-1-PDT exerted a potent cytotoxic effect on pancreatic cancer cells in vitro, which could be abolished by the ROS scavenger N-acetyl-L-cysteine (NAC). The death mode caused by YLG-1-PDT was apoptosis, accompanied by upregulated Bax and cleaved Caspase-3 and decreased Bcl-2 expression. The results from the IVIS images suggested that the optimal administration route was intratumoral (IT) injection and that the best time to conduct YLG-1-PDT was 2 h post-IT injection. Consistent with the results in vitro, YLG-1-PDT showed great growth inhibition effects on pancreatic cancer cells in a mouse model. CONCLUSION: YLG-1 is a potential photosensitizer for pancreatic cancer PDT via IT injection, the mechanisms of which are associated with inducing ROS and promoting apoptosis.

Biodistribution and toxicity assessment of intratumorally injected arginine-glycine-aspartic acid peptide conjugated to CdSe/ZnS quantum dots in mice bearing pancreatic neoplasm.

Quantum dots (QDs) conjugated with arginine-glycine-aspartic acid (RGD) peptides (which are integrin antagonists) are novel nanomaterials with the unique optical property of high molar extinction coefficient, and they have potential utility as photosensitizers in photodynamic therapy (PDT). Our group previously demonstrated significant benefits of using PDT with QD-RGD on pancreatic tumor cells. This study aimed to evaluate the biodistribution and toxicity of QD-RGD in mice prior to in vivo application. Mice with pancreatic neoplasms were intratumorally injected with varying doses of QD-RGD, and the biodistribution 0-24 h post injection was compared to that in control mice (intravenously injected with unconjugated QD). Various tissue samples were collected for toxicity analyses, which included inductively coupled plasma mass spectrometry (ICP-MS) to assess Cd2+ concentrations and hematoxylin-eosin staining for histopathological examination. Fluorescent imaging revealed relatively sufficient radiant efficiency in mice under specific conditions. The ICP-MS and HE data showed no significant signs of necrosis due to Cd2+ release by QDs. The mice survived well and had no apparent weakness or weight loss during the 4 weeks post injection. These findings provide novel insights into the biodistribution of QD-RGD and encourage profound in vivo studies regardless of safety concerns. These findings alleviate safety concerns and provide novel insights into the biodistribution of QD-RGD, offering a solid foundation for comprehensive in vivo studies.

Effects of arginine-glycine-aspartic acid peptide-conjugated quantum dots-induced photodynamic therapy on pancreatic carcinoma in vivo.

Quantum dots (QDs) conjugated with integrin antagonist arginine-glycine-aspartic acid (RGD) peptides (QDs-RGD) are novel nanomaterials with a unique optical property: a high molar extinction coefficient. Previously, we have shown that QDs-RGD demonstrate a photodynamic therapy (PDT) effect as new photosensitizers for the pancreatic cancer cell line SW1990 in vitro. Here, we investigate the application of QDs-RGD in mice bearing pancreatic tumors using PDT. To ensure that more photosensitizers accumulated in tumors, QDs-RGD were injected intratumorally. After selection of an adequate dosage for injection from analyses of biodistribution images captured by an IVIS system, PDT was initiated. Three groups were created according to different PDT procedures. In group 1, mice were injected with QDs-RGD intratumorally, and an optical fiber connected to a laser light was inserted directly into the tumor. Irradiation was sustained for 20 min with a laser light (630 nm) at 100 mW/cm2. In group 2, the laser optical fiber was placed around, and not inserted into, tumors. In group 3, PDT was conducted as in group 1 but without injection of QDs-RGD. After 28 days of observation, tumors on the back of mice in group 1 grew slowly (V/V0 =3.24±0.70) compared with the control groups, whose tumors grew quickly, and the mean V/V0 reached 6.08±0.50 (group 2) and 7.25±0.82 (group 3). Histology of tumor tissues showed more necrotic tissues, more inflammatory cells, and less vascular tissue in the PDT group than those in the control groups. These results suggest that QDs-RGD-mediated PDT, with illumination using an optical fiber inserted directly into the tumor, can inhibit the growth of SW1990 tumors with high efficiency in nude mice.

Expression Changes of Long Noncoding RNA in the Process of Endothelial Cell Activation.

BACKGROUND: Endothelial cells have been shown to be in response to a variety of local and systemic stimuli, and are able to transition between quiescent and activated states. Endothelial cell activation is critical for the pathogenesis of various cardiovascular diseases. However, the expression changes of long non-coding RNAs (lncRNAs) are still unknown in the process of endothelial cell activation. Thus, this study was aimed to investigate expression changes of lncRNA before and after endothelial cell activation. MATERIALS AND METHODS: In an experimental model of peripheral venous congestion, endothelial cells were activated and analyzed with Affymetrix HG-U133 plus2.0 microarray. We analyzed these microarray data and reannotated the microarray probes for lncRNA. RESULTS: According to the definition of absolute fold change>2 and p value <0.05, 27 differentially expressed lncRNAs were identified and only 1 lncRNA transcript, ENST00000509256 was down-regualted. Co-expression network of lncRNA and mRNA were constructed to predict function of the dysregulated lncRNA. Gene set enrichment analyses suggested that these ENST00000509256 was associated with many important functions, such as cell-cell signaling and regulation of cell differentiation. CONCLUSION: Many lncRNAs are dysregulated upon endothelial cell activation and further experiments are needed to identify the potential biological functions of these lncRNAs.

HOXB8 promotes tumor metastasis and the epithelial-mesenchymal transition via ZEB2 targets in gastric cancer.

PURPOSE: The homeobox B8 (HOXB8) functions as a sequence-specific transcription factor that is involved in development. Increased expression of this gene is associated with a wide variety of tumor; however, its function in gastric cancer has not been clarified. In the present study, the expression of HOXB8 in gastric cancer tissues and influence of HOXB8 on gastric cancer cellular were evaluated. METHODS: The expression levels of HOXB8 mRNA in human gastric cancer tissues were analyzed through quantitative RT-PCR. To test the role of HOXB8 in gastric cancer metastasis, the cell transwell assay was performed. Microarray, ChIP-qPCR, and Western blot were used to explore the possible mechanism that HOXB8 promotes gastric cancer cells metastasis. RESULTS: In this study, we found that HOXB8 showed higher expression in metastatic tissues than no-metastatic tissues. Overexpression of HOXB8 can promote gastric cancer cells migration and invasion, while silencing HOXB8 leads to the opposite results. Overexpression of HOXB8 also increases the rate of metastasis in NCI-N87 mice, while silencing HOXB8 has the opposite results. Furthermore, HOXB8 promotes epithelial-mesenchymal transformation of AGS cells. We also found that ZEB2 can interact with HOXB8 and may be a downstream factor of HOXB8 by using microarray. Knockdown of ZEB2 can inhibit HOXB8-induced migration and invasion capacity, as well as the epithelial-mesenchymal transformation in gastric cancer cells. CONCLUSIONS: The results showed that HOXB8 plays an important role in the development and metastasis of gastric carcinoma.

CdSe/ZnS quantum dots induce photodynamic effects and cytotoxicity in pancreatic cancer cells.

AIM: To investigate the photodynamic effect of CdSe/ZnS quantum dots (QDs) on pancreatic cancer cells and elucidate the probable mechanisms. METHODS: The pancreatic cancer cell line SW1990 was treated with different concentrations of CdSe/ZnS QDs (0, 0.5, 1.0, 1.5, 2.0, 2.5 µmol/L), with or without illumination. The viability of SW1990 cells was tested using the Cell Counting Kit-8 (CCK-8) assay. The ultrastructural changes of SW1990 cells were observed by transmission electron microscopy. Apoptosis was detected by nuclear staining and flow cytometry (FCM). Reactive oxygen species (ROS) were measured by dichlorofluorescein diacetate via fluorescence microscopy. Expression of Bax, Bcl-2 and caspase-3 was measured by real-time polymerase chain reaction (PCR) and protein immunoblotting 24 h after SW1990 cells were treated with CdSe/ZnS QDs and illuminated. RESULTS: The CCK-8 assay results showed that both CdSe/ZnS QDs with and without illumination suppressed SW1990 cell proliferation. Cell viability was significantly lower when illuminated or with a longer incubation time and a higher light dose. CdSe/ZnS QDs with illumination caused ultrastructural changes in SW1990 cells, such as organelle degeneration and chromatin condensation and aggregation at the periphery of the nucleus. Fluorescence microscopy and FCM showed that CdSe/ZnS QDs (1.5 µmol/L) with illumination increased SW1990 cell apoptosis (53.2%) and ROS generation compared with no illumination. Real-time PCR showed that expression of Bax and caspase-3 was upregulated and Bcl-2 was downregulated. Immunoblotting results were consistent with real-time PCR results. Inhibition of ROS and apoptosis both attenuated QD-photodynamic-therapy-induced cell death. CONCLUSION: CdSe/ZnS QDs can be used as a photosensitizer to inhibit SW1990 cell proliferation through ROS generation and apoptotic protein expression regulation.

Engineering of lipid prodrug-based, hyaluronic acid-decorated nanostructured lipid carriers platform for 5-fluorouracil and cisplatin combination gastric cancer therapy.

PURPOSE: The first-line chemotherapy treatment protocol for gastric cancer is combination chemotherapy of 5-fluorouracil (5-FU) and cisplatin (CDDP). The aim of this study was to engineer prodrug-based nanostructured lipid carriers (NLC) platform for codelivery of 5-FU and CDDP to enhance therapy and decrease toxicity. METHODS: First, 5-FU-stearic acid lipid conjugate was synthesized by two steps. Second, 5-FU-stearic acid prodrug and CDDP were loaded in NLC. Finally, hyaluronic acid (HA) was coated onto NLC surface. Average size, zeta potential, and drug loading capacity of NLC were evaluated. Human gastric cancer cell line BGC823 (BGC823 cells) was used for the testing of in vitro cytotoxicity assays. In vivo antitumor activity of NLC was evaluated in mice bearing BGC823 cells model. RESULTS: HA-coated 5-FU-stearic acid prodrug and CDDP-loaded NLC (HA-FU/C-NLC) showed a synergistic effect in combination therapy and displayed the greatest antitumor activity than all of the free drugs or uncoated NLC in vitro and in vivo. CONCLUSION: This work reveals that HA-coated NLC could be used as a novel carrier to code-liver 5-FU and CDDP for gastric cancer therapy. HA-FU/C-NLC could be a promising targeted and combinational therapy in nanomedicine.

Value of bevacizumab in treatment of colorectal cancer: A meta-analysis.

AIM: To assess the efficacy and safety of bevacizumab in the treatment of colorectal cancer. METHODS: All randomized controlled trials of bevacizumab for the treatment of colorectal cancer from January 2003 to June 2013 were collected by searching the Cochrane Library, PubMed, Chinese National Knowledge Infrastructure and Wanfang databases. The primary endpoint was overall survival (OS), and the secondary endpoints were progression-free survival, overall response rate and adverse events. Two reviewers extracted data independently. Statistical analyses were performed with Stata 12.0. The degree of bias was assessed using funnel plots for the effect size of OS at the primary endpoint. RESULTS: Following the inclusion criteria and exclusion criteria, ten studies comprising 6977 cases were finally included, of which nine were considered to be of high quality (4-7 points) and one of low quality (1-3 points). Our meta-analysis revealed the efficacy of bevacizumab in patients with colorectal cancer in terms of OS (HR = 0.848, 95%CI: 0.747-0.963), progression-free survival (HR = 0.617, 95%CI: 0.530-0.719), and overall response rate (OR = 1.627, 95%CI: 1.199-2.207). Regarding safety, higher rates of grade ≥ 3 hypertension, proteinuria, bleeding, thrombosis, and gastrointestinal perforation were observed in the bevacizumab treatment group (P < 0.05); however, the incidence of serious toxicity was very low. There was no publication bias in the 10 reports included in this meta-analysis. CONCLUSION: The clinical application of bevacizumab in colorectal cancer is effective with good safety.

Effects of integrin-targeted photodynamic therapy on pancreatic carcinoma cell.

AIM: To investigate the effects of photodynamic therapy with quantum dots-arginine-glycine-aspartic acid (RGD) probe as photosensitizer on the proliferation and apoptosis of pancreatic carcinoma cells. METHODS: Construction of quantum dots-RGD probe as photosensitizer for integrin-targeted photodynamic therapy was accomplished. After cells were treated with photodynamic therapy (PDT), the proliferation of SW1990 cells were measured by methyl thiazolyl tetrazolium assay. Morphologic changes, cell cycle retardance and apoptosis were observed under fluoroscope and flow cytometry. The expression of myeloid cell leukemia-1 (Mcl-1), protein kinase B (Akt) and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) mRNA were detected by reverse transcription-polymerase chain reaction. The amount of reactive oxygen species were also evaluated by fluorescence probe. RESULTS: The photodynamic therapy with quantum dots-RGD probe as photosensitizer significantly inhibited cell proliferation (P < 0.01). Apoptotic cells and morphologic changes could be found under optical microscope. The FCM revealed PDT group had more significant cell apoptosis rate compared to control cells (F = 130.617, P < 0.01) and cell cycle G0/G1 and S retardance (P < 0.05) compared to control cells. The expression of Mcl-1 and Akt mRNA were down-regulated, while expression of TRAIL mRNA was up-regulated after cells treated with PDT. PDT group had more significant number of cells producing reactive oxygen species compared to control cells (F = 3262.559, P < 0.01). CONCLUSION: The photodynamic therapy with quantum dots-RGD probe as photosensitizer significantly inhibits cell proliferation and increases apoptosis in SW1990 cells.

Effects of medical adhesives in prevention of complications after endoscopic submucosal dissection.

AIM: To evaluate the use of medical adhesive spray in endoscopic submucosal dissection (ESD). METHODS: Patients who underwent ESD between January 2009 and June 2012 (n = 173) were enrolled in the prospective randomized study. Two patients undergoing surgery due to severe intraoperative hemorrhage and failed hemostasis were excluded, and the remaining 171 patients were randomly divided into two groups: group A (medical adhesive group, n = 89) and group B (control group, n = 82). In group A, a medical adhesive spray was evenly applied after routine electrocoagulation and hemostasis using hemostatic clip after ESD. Patients in group B only treated with routine wound management. Intraoperative and postoperative data were collected and compared. RESULTS: In all 171 patients, ESD was successfully completed. There was no significant difference in the average treatment time between groups A and B (59.4 min vs 55.0 min, respectively). The average length of hospital stay was significantly different between group A and B (8.89 d vs 9.90 d, respectively). The incidence of intraoperative perforation was 10.1% in group A and 9.8% in group B, and was not significantly different between the two groups. In all cases, perforations were successfully managed endoscopically and with conservative treatment. The incidence of postoperative delayed bleeding in group A was significantly lower than that in group B (0.00% vs 4.88%, respectively). CONCLUSION: ESD is an effective minimally invasive treatment for gastrointestinal precancerous lesions or early-stage gastrointestinal cancer. Medical adhesive spray is effective in preventing delayed bleeding after ESD, and can thus reduce the average length of hospital stay.

Antifibrotic effect of N-acetyl-seryl-aspartyl-lysyl-proline on bile duct ligation induced liver fibrosis in rats.

AIM: To investigate the preventive effect of N-acetyl-seryl-aspartyl-lysyl-proline (AcSDKP) on bile duct ligation (BDL)-induced liver fibrosis in rats. METHODS: Liver fibrosis in rats was induced by BDL and AcSDKP was infused subcutaneously for 2 wk via a osmotic minipump (Alzet 2ML4) immediately after BDL operation. After scarifying, serum and liver specimens were collected. Hematoxylin and eosin staining, Sirius red staining, enzyme linked immunosorbent assay, Western blot or real-time polymerase chain reaction were used to determinate liver functions, histological alterations, collagen deposition, mRNA expression of markers for fibroblasts, transforming growth factor-ß1 (TGF-ß1) and bone morphogenetic protein-7 (BMP-7). RESULTS: When compared to model rats, chronic exogenous AcSDKP infusion suppressed profibrogenic TGF-ß1 signaling, α-smooth muscle actin positivity (α-SMA), fibroblast specific protein-1 (FSP-1) staining and collagen gene expression. Col I, Col III, matrix metalloproteinase-2, tissue inhibitors of metalloproteinase-1 and tissue inhibitors of metalloproteinase-2 mRNA expressions were all significantly downregulated by AcSDKP infusion (2.02 ± 1.10 vs. 14.16 ± 6.50, 2.02 ± 0.45 vs. 10.00 ± 3.35, 2.91 ± 0.30 vs. 7.83 ± 1.10, 4.64 ± 1.25 vs. 18.52 ± 7.61, 0.46 ± 0.16 vs. 0.34 ± 0.12, respectively, P < 0.05). Chronic exogenous AcSDKP infusion attenuated BDL-induced liver injury, inflammation and fibrosis. BDL caused a remarkable increase in alanine transaminase, aspartate transaminase, total bilirubin, and prothrombin time, all of which were reduced by AcSDKP infusion. Mast cells, collagen accumulation, α-SMA, TGF-ß1, FSP-1 and BMP-7 increased. The histological appearance of liver specimens was also improved. CONCLUSION: Infusion of exogenous AcSDKP attenuated BDL-induced fibrosis in the rat liver. Preservation of AcSDKP may be a useful therapeutic approach in the management of liver fibrosis.

Comparison between air and carbon dioxide insufflation in the endoscopic submucosal excavation of gastrointestinal stromal tumors.

AIM: To evaluate the safety and efficacy of CO(2) insufflation compared with air insufflation in the endoscopic submucosal excavation (ESE) of gastrointestinal stromal tumors. METHODS: Sixty patients were randomized to undergo endoscopic submucosal excavation, with the CO(2) group (n = 30) and the air group (n = 30) undergoing CO(2) insufflation and air insufflation in the ESE, respectively. The end-tidal CO(2) level (pETCO(2)) was observed at 4 time points: at the beginning of ESE, at total removal of the tumors, at completed wound management, and 10 min after ESE. Additionally, the patients' experience of pain at 1, 3, 6 and 24 h after the examination was registered using a visual analog scale (VAS). RESULTS: Both the CO(2) group and air group were similar in mean age, sex, body mass index (all P > 0.05). There were no significant differences in PetCO(2) values before and after the procedure (P > 0.05). However, the pain scores after the ESE at different time points in the CO(2) group decreased significantly compared with the air group (1 h: 21.2 ± 3.4 vs 61.5 ± 1.7; 3 h: 8.5 ± 0.7 vs 42.9 ± 1.3; 6 h: 4.4 ± 1.6 vs 27.6 ± 1.2; 24 h: 2.3 ± 0.4 vs 21.4 ± 0.7, P < 0.05). Meanwhile, the percentage of VAS scores of 0 in the CO(2) group after 1, 3, 6 and 24 h was significantly higher than that in the air group (60.7 ± 1.4 vs 18.9 ± 1.5, 81.5 ± 2.3 vs 20.6 ± 1.2, 89.2 ± 0.7 vs 36.8 ± 0.9, 91.3 ± 0.8 vs 63.8 ± 1.3, respectively, P < 0.05). Moreover, the condition of the CO(2) group was better than that of the air group with respect to anal exsufflation. CONCLUSION: Insufflation of CO(2) in the ESE of gastrointestinal stromal tumors will not cause CO(2) retention and it may significantly reduce the level of pain, thus it is safe and effective.