Xiao-Bo Li

Predictive role of capsule endoscopy on the insertion route of double-balloon enteroscopy.

BACKGROUND AND STUDY AIMS Double-balloon enteroscopy (DBE) has been suggested to be more efficient if based on the results of screening video capsule endoscopy (VCE). We evaluated the utility of VCE for predicting the best insertion route of DBE for the evaluation and treatment of small-bowel lesions. PATIENTS AND METHODS Results of studies of patients with complete VCE examination of the small bowel and with findings confirmed by DBE are reported. A location index of lesions found on VCE was defined as the time from the pylorus to the lesion as a percentage of the time from the pylorus to the ileocecal valve. Based on our previous retrospective evaluation, a cut-off value of 0.6 was adopted, and the oral or anal approach was selected when the index was < or = 0.6 or > 0.6, respectively. RESULTS Data from 60 patients who underwent both VCE and DBE examinations and in whom the capsule reached the cecum were evaluated. Lesions shown on VCE were all reached by the first DBE procedures (41 orally and 19 anally). Based on the time index cut-off value of 0.6, the accuracy of selecting the insertion route of DBE was 100 %. CONCLUSION DBE is an effective approach for confirming VCE results. In patients with complete small-bowel investigation by VCE, the best insertion route for DBE can be reliably indicated using a time index based on the VCE records.

A Prospective Study on Evaluating the Diagnostic Yield of Video Capsule Endoscopy Followed by Directed Double-Balloon Enteroscopy in Patients with Obscure Gastrointestinal Bleeding

AimsVideo capsule endoscopy (VCE) and double-balloon enteroscopy (DBE) are two novel methods for examining the small bowel and could be complementary to each other. The aim of the present study is to prospectively evaluate the diagnostic yield of VCE followed by a directed DBE in patients with obscure gastrointestinal (GI) bleeding.MethodsPatients with obscure gastrointestinal bleeding for a complete VCE examination were involved in the study. DBE was recommended after a negative or indeterminate finding of VCE. The diagnostic and follow-up data were collected for analysis.ResultsA total of 190 patients with a complete VCE examination were enrolled in the study. The overall positive detection rate for small-bowel disease in the VCE group was 86.8% (165/190), while 63.7% (121/190) patients were definitely diagnosed. Fifty-one patients with indeterminate (44 cases) and negative (seven cases) findings of first VCE underwent DBE procedures. A total of 18 patients with negative VCE findings refused the further examination. DBE demonstrated a positive finding in 66.7% (34/51) patients, 33 from indeterminate group and one from the negative group. Following an unrevealing DBE, at surgical follow-up, three further negative DBE procedures were documented. The overall diagnostic yield was 88.9%, including 121 diagnoses made by VCE alone and 48 by both VCE and DBE (confirmed at surgery or other treatments). The negative predictive value (NPV) and positive predictive value (PPV) of DBE in indeterminate VCE were 81.8 and 100%, respectively.ConclusionsCapsule endoscopy followed by directed double-balloon enteroscopy is a good strategy for investigating the causes of obscure GI bleeding and especially in confirming indeterminate and negative findings from VCE.

Assessment of capsule endoscopy scoring index, clinical disease activity, and C‐reactive protein in small bowel Crohn's disease

Small bowel Crohns disease (SBCD) patients are frequently assessed by capsule endoscopy (CE), which enables direct visualization of small bowel mucosal abnormalities; however, the correlations between CE scoring index (CESI), C‐reactive protein (CRP), and disease activity indices remain undefined. We aimed to determine correlations between the CESI, clinical disease activity indices, and CRP in SBCD patients.

LRG1 modulates epithelial-mesenchymal transition and angiogenesis in colorectal cancer via HIF-1α activation

BackgroundLeucine-rich-alpha-2-glycoprotein 1 (LRG1) has been reported to be involved in several tumors, whether it participates in colorectal cancer (CRC) progression remains unclear. Here, we investigated the biological function and underlying molecular mechanisms of LRG1 in CRC.MethodsThe mRNA and protein levels of LRG1 were assessed in CRC tissues through RT-PCR and immunohistochemistry, respectively. HCT116 and SW480 cells were treated with LRG1 siRNA, control siRNA, or recombinant LRG1. Transwell invasion assays and wound healing assays were performed to evaluate the invasion and migration of CRC cells. Epithelial-to-mesenchymal transition (EMT) markers of E-cadherin, VDR, N-cadherin, α-SMA, Vimentin and Twist1 were detected by RT-PCR and western blot. Enzyme-linked immunosorbent assay was used to measure the secretion level of VEGF-A. Conditioned medium from CRC cells was collected for endothelial cell migration, tube formation and aortic ring sprouting assays.ResultsLRG1 was overexpressed in CRC tissues and associated with cancer aggressiveness. LRG1 was further found to induce the EMT process, as well as CRC cell migration and invasion capacity. In addition, LRG1 promoted VEGF-A expression in CRC cells and contributed to tumor angiogenesis. Furthermore, HIF-1α could be induced by LRG1 in a concentration- and time-dependent manner, which was responsible for LRG1-induced VEGF-A expression and EMT.ConclusionsThe present study suggests that LRG1 plays a crucial role in the progression of CRC by regulating HIF-1α expression, thereby may be a promising therapeutic target of CRC.

High-mobility group Box 1: A novel inducer of the epithelial–mesenchymal transition in colorectal carcinoma

Proinflammatory cytokine high-mobility group box 1 (HMGB1) mediates critical processes of tumour metastasis. Because the epithelial-to-mesenchymal transition (EMT) is a key player in metastasis, the aim of this study was to determine whether and through which mechanism HMGB1 induces EMT in colorectal carcinoma. The direct treatment of cells with recombinant human HMGB1 induced alterations in the epithelial morphology consistent with the EMT and enhanced cell migration through a process mediated by the receptor for advanced glycation end-products (RAGE). The levels of Snail and phospho-NF-κB were upregulated during the HMGB1-induced EMT, and these effects were reversed by inhibiting Snail and NF-κB. In addition, HMGB1 increased the expression of MMP-7 but not that of MMP-9, and this effect was also regulated by Snail/NF-κB signalling. Collectively, these findings indicate that HMGB1 acts as a potent driver of cancer EMT through the RAGE/Snail/NF-κB signalling pathways accompanied by the activation of MMP-7, thereby suggest the feasibility of targeting HMGB1 for the treatment of tumour metastasis.

Carbon dioxide insufflation improves the intubation depth and total enteroscopy rate in single-balloon enteroscopy: a randomised, controlled, double-blind trial

Objective The total enteroscopy rate of single-balloon enteroscopy (SBE) using air insufflation is not satisfactory, and whether carbon dioxide (CO2) insufflation increases the total enteroscopy rate of SBE is unknown. This randomised controlled trial aimed to determine whether CO2 insufflation facilitates the intubation depth and total enteroscopy rate of SBE. Design A total of 214 eligible patients referred for SBE were randomised to receive either air or CO2 insufflation, and included in the intention-to-test (ITT) analysis. In addition, 199 patients in whom enteroscopy was completed were included in the per-protocol (PP) analysis. Both the patients and endoscopists were blinded, and the intubation depth and total enteroscopy rate were defined as the primary outcomes. Results The CO2 group showed a superiority of intubation in the ITT analysis (oral route: 323.8±64.2 vs 238.3±68.6 cm; anal route: 261.6±74.2 vs 174.7±62.1 cm, both p<0.001), and the total enteroscopy rate (34.9% vs 17.6%, p=0.006). Similar results were obtained in a PP analysis for both outcomes. In addition, in the PP analysis, the addition of circumference after the procedure was less in the CO2 group (0.8±0.6 vs 3.3±1.8 cm, p=0.005) for the oral route. No serious complications were reported. The overall percentage of procedures with significant pathological findings was 52.8%; the rates were 58.5% and 47.2% (p=0.100, ITT analysis) in the CO2 and air groups, respectively. Conclusions CO2 insufflation improves the intubation depth and total enteroscopy rate in SBE with a good safety profile and acceptability compared with that of air, and thus is recommended for clinical utilisation. Trial registration number ClinicalTrial.gov identifier: NCT01758900.

A novel modality for the estimation of the enteroscope insertion depth during double-balloon enteroscopy

BACKGROUND Until now, the insertion depth of the enteroscope during double-balloon enteroscopy (DBE) could only be estimated. However, the currently available methods have limitations, and development of newer, simple, and accurate modalities is needed. OBJECTIVE To evaluate the accuracy of a novel method for evaluation of enteroscope insertion depth during DBE. DESIGN Prospective, single-center cohort study. SETTING Tertiary referral university hospital. PATIENTS Fifty-one patients who had lesions found during 41 antegrade and 10 retrograde DBEs and treated by surgery were enrolled in this study. INTERVENTIONS The length of the ligament of Treitz/ileocecal valve lesion was estimated by adding the forward enteroscope length during each cycle of passage and by calculating the overtube insertion length (every 5 cm of overtube advancement means 40 cm of enteroscope advancement based on preliminary observations) during DBE, respectively, and was evaluated at surgery. MAIN OUTCOME MEASUREMENTS The length from the ligament of Treitz/ileocecal valve to the lesion. RESULTS Surgical evaluation was used as the standard. Regardless of insertion route, the mean difference from surgery in evaluation of enteroscope insertion length between using the enteroscope method and the overtube method was 19 cm (range 0-50 cm) and 17 cm (range 0-60 cm), respectively (P > .05). LIMITATIONS Small number of patients with a case series study design. CONCLUSIONS Calculating the length of the overtube passage is accurate, and it is simple to estimate the insertion depth of the enteroscope during DBE, which is useful in clinical practice.

EVALUATION OF NARROW-BAND IMAGING IN THE DIAGNOSIS OF COLORECTAL LESIONS: IS A LEARNING CURVE INVOLVED?

The usefulness of endoscopy narrow‐band imaging (NBI) in differentiating colorectal lesions has been demonstrated. However, the learning curve associated with this technique is a concern for endoscopists.

Current Clinical Applications of Magnifying Endoscopy with Narrow Band Imaging in the Stomach

Narrow band imaging (NBI), in conjunction with magnifying endoscopy (ME), has arisen more and more attention in the area of advanced endoscopy. By enhancing the mucosal microvascular architecture and surface pattern, it is feasible to use ME-NBI to identify subtle changes associated with gastric inflammation, atrophy, intestinal metaplasia, and early gastric cancer. The new technique thus plays a valuable role in therapeutic decision-making, endoscopic treatment process, postoperative evaluation, and follow-up examination. To date, many criteria or evaluation method of ME-NBI has been proposed. This paper aims to summarize the various diagnosing classifications and the current clinical applications of ME-NBI in the stomach.

Operative link on gastritis assessment stage is an appropriate predictor of early gastric cancer

AIM To assess the predictive value of Operative Link on Gastritis Assessment (OLGA) and Operative Link on Gastric Intestinal Metaplasia Assessment (OLGIM) stages in gastric cancer. METHODS A prospective study was conducted with 71 patients with early gastric cancer (EGC) and 156 patients with non-EGC. All patients underwent endoscopic examination and systematic biopsy. Outcome measures were assessed and compared, including the Japanese endoscopic gastric atrophy (EGA) classification method and the modified OLGA method as well as the modified OLGIM method. Helicobacter pylori (H. pylori) status was determined for all study participants. Stepwise logistic regression modeling was performed to analyze correlations between EGC and the EGA, OLGA and OLGIM methods. RESULTS For patients with EGC and patients with non-EGC, the proportions of moderate-to-severe EGA cases were 64.8% and 44.9%, respectively (P = 0.005), the proportions of OLGA stages III-IV cases were 52.1% and 22.4%, respectively (P < 0.001), and the proportions of OLGIM stages III-IV cases were 42.3% and 19.9%, respectively (P < 0.001). OLGA stage and OLGIM stage were significantly related to EGA classification; specifically, logistic regression modeling showed significant correlations between EGC and moderate-to-severe EGA (OR = 1.95, 95% CI: 1.06-3.58, P = 0.031) and OLGA stages III-IV (OR = 3.14, 95%CI: 1.71-5.81, P < 0.001), but no significant correlation between EGC and OLGIM stages III-IV (P = 0.781). H. pylori infection rate was significantly higher in patients with moderate-to-severe EGA (75.0% vs 54.1%, P = 0.001) or OLGA/OLGIM stages III-IV (OLGA: 83.6% vs 55.8%, P < 0.001; OLGIM: 83.6% vs 57.8%, P < 0.001). CONCLUSION OLGA classification is optimal for EGC screening. A surveillance program including OLGA stage and H. pylori infection status may facilitate early detection of gastric cancer.