Generation of magnifying endoscopic images of gastric neoplasms based on an all-in-focus algorithm.

BACKGROUND AND AIM: Magnifying endoscopy is useful for diagnosis of early gastrointestinal neoplasms by visualizing microvascular (MV) and microsurface (MS) structures of the mucosa when combined with image-enhanced endoscopy. However, precise control of the endoscope is needed because the depth of focus is narrow and the target may move. These problems may be overcome by the all-in-focus (AIF) technique, which was developed in the engineering field. The aim of the study was to evaluate magnifying endoscopic image with AIF algorithm. METHODS: Twenty gastric neoplasms were examined. Images were acquired at 80× magnification and converted to endoscopic images with an AIF algorithm (EI-AIF). The focus area and MV and MS patterns in the original image and the EI-AIF were compared on a 5-point Likert scale, where 5 indicates that the EI-AIF was superior. Intraclass correlation coefficients (ICCs) were used to assess the inter-evaluator reliability. An image quality measurement value was calculated for each image as an indicator of the degree of focus. RESULTS: The scores for focus area, MV, and MS were 4.78 ± 0.45 (ICC = 0.63), 4.12 ± 0.76 (ICC = 0.70), and 4.72 ± 0.52 (ICC = 0.45), respectively, with the EI-AIF significantly superior for all three items (P < 0.05 by Student's t-test). ICCs for the focus area and MV were > 0.60, indicating strong inter-evaluator reliability. Image quality measurement was higher for the EI-AIF compared with the original image in every case. CONCLUSIONS: Endoscopic observation with AIF algorithm gives a better image quality that allows easier evaluation of MV and MS patterns. This technique may resolve the difficulties with magnifying endoscopic observation.

Fecal calprotectin reflects endoscopic activity in patients with small-bowel Crohn's disease according to double-balloon endoscopy findings.

Fecal calprotectin (FC) has drawn attention as a biomarker in the evaluation of Crohn's disease (CD). However, few reports have provided a detailed examination of the relationship between small-bowel CD lesions and FC levels. The present study aimed to examine the entire small bowel using double-balloon endoscopy (DBE) and to determine the relationship between the endoscopic activity in small-bowel CD and FC levels. Twenty small-bowel CD patients, who underwent DBE, were prospectively enrolled. Endoscopic evaluation was based on the simple endoscopic score for CD, with the small bowel divided into four regions. This score was defined as the double-balloon endoscopic score for CD (DES-CD). Furthermore, to focus on mucosal membrane damage, we used the partial DES-CD (pDES-CD), in which presence of stenosis was excluded from DES-CD. DES-CD revealed a correlation with FC (γ = 0.691, P = 0.001) and C-reactive protein (CRP) (γ = 0.631, P = 0.003) levels. Furthermore, pDES-CD showed a correlation with the FC level (γ = 0.747, P < 0.001), erythrocyte sedimentation rate (γ = 0.492, P = 0.028), and the CRP level (γ = 0.605, P = 0.005). CD Activity Index and endoscopic score showed no correlation. Our results revealed a correlation between the endoscopic activity in small-bowel CD and FC levels. Furthermore, pDES-CD showed a strong correlation with FC levels. This may be because FC levels were elevated due to mucosal membrane damages, rather than stenoses.

Nomogram-based prediction of rebleeding in small bowel bleeding patients: the 'PRSBB' score.

Small bowel capsule endoscopy (SBCE) and balloon-assisted endoscopy (BAE) have revolutionized the diagnosis and treatment of small bowel bleeding (SBB), allowing access to the small bowel and identification of specific bleeding lesions. However, some patients experience rebleeding after small bowel investigation, and there are no definitive algorithms for determining the most appropriate follow-up strategy in SBB patients. We developed and validated a nomogram that can predict rebleeding risk and be used to develop a risk-stratified follow-up strategy in SBB patients. A retrospective study was performed using data from 401 SBB patients who underwent SBCE at Nagoya University Hospital. We developed and internally validated a predictive model for rebleeding in the form of a nomogram using Cox regression models and a bootstrap resampling procedure. Optimal risk factors were selected according to the least absolute shrinkage and selection operator (LASSO). The LASSO method identified 8 independent predictors of rebleeding that could be assessed to obtain a 'predicting rebleeding in SBB', or 'PRSBB' score: age, sex, SBB type, transfusion requirement, cardiovascular disease, liver cirrhosis, SBCE findings, and treatment. The c-statistic for the predictive model was 0.681. In conclusion, our PRSBB score can help clinicians devise appropriate follow-up plans.

Clinical significance of gastrointestinal patency evaluation by using patency capsule in Crohn's disease.

Capsule endoscopy (CE) enables noninvasive visualization of the small bowel in Crohn's disease (CD), but should not be conducted in patients with bowel obstruction. Patency capsule (PC) can be ingested before conducting the CE examination to ensure patency of the gastrointestinal (GI) tract. This study aimed to evaluate the clinical significance of GI patency which the PC demonstrated. A retrospective review of the medical records was conducted with 99 consecutive patients with CD who underwent PC and CE at Nagoya University Hospital from January 2010 to May 2015. By using the Cox proportional hazards model, the association between the GI patency evaluated using the PC and the outcome in terms of the rate of patients who needed admission or surgery during the 2-year follow-up was examined. Of all 99 patients who ingested the PC, 84 (84.8%) were diagnosed as not having bowel obstruction, and therefore were eligible for CE (P group). Of the 15 patients in whom bowel obstruction was suspected (NP group), 12 patients underwent either the balloon-assisted endoscopy (n=10) or enteroclysis (n=2), and 11 were confirmed to have small bowel stricture. Non-admission rates of the P and NP groups during the 2-year observation period were 74/84 (88.0%) and 8/15 (53.3%), respectively (P<0.001). Non-operation rates of the P and NP groups during the 2-year observation period were 80/84 (95.2%) and 9/15 (60.0%), respectively (P<0.001). In conclusion, GI patency as diagnosed using the PC was associated with a significantly lower incidence of admission or surgical intervention.

Increase in breath hydrogen concentration was correlated with the main pancreatic duct stenosis.

BACKGROUND: Hydrogen is produced from unabsorbed carbohydrates in the intestine through degradation and metabolism by hydrogenase of intestinal bacteria. The hydrogen is then partially diffused into blood flow and released and detected in exhaled breath. Pancreatic juice production is decreased in patients with reduced pancreatic exocrine function, including those with pancreatic cancer, thus decreasing digestion and absorption of nutrients including carbohydrates, which may increase undigested carbohydrates in the intestine and increase breath hydrogen concentration (BHC). The aim of this study was to investigate the association between BHC and pancreatic diseases. METHODS: A retrospective study was designed and 68 patients underwent morning fasting breath hydrogen test. Since there is no clear standard, normal BHC, the median of the measured values from the subjects (9 ppm) was adopted as the standard. The subjects were classified into those with a value exceeding the median (BHC high group: 32 patients) and a value equal to or below the median (BHC low group: 36 patients). Patients characteristics, blood test results and imaging findings characteristic of pancreatic diseases were compared between the groups. RESULTS: The age was significantly higher (P = 0.010) and the incidences of pancreatic ductal adenocarcinoma and autoimmune pancreatitis were significantly higher (P = 0.018 and P = 0.004, respectively) in the BHC high group. With respect to the blood test items, the Alb level was significantly lower in the BHC high group (P = 0.005). With respect to the characteristic imaging findings of pancreatic diseases, the proportions of patients with pancreatic enlargement, the main pancreatic duct (MPD) stenosis, and the MPD dilatation were significantly higher in the BHC high group (P = 0.022, P < 0.001, and P = 0.002, respectively). On univariate analysis, only the MPD stenosis was extracted as an independent factor (P = 0.014). CONCLUSION: It was suggested that the fasting BHC is associated with pancreatic diseases causing stenosis of the MPD, including pancreatic cancer (UMIN000020777).

In vivo histological diagnosis for gastric cancer using endocytoscopy.

AIM: To examine usefulness of virtual biopsy using endocytoscopy by comparing the in vivo endocytoscopic and histopathological images of gastric cancers. METHODS: Endocytoscopy was performed in 30 patients with early gastric cancer. Of these, 26 patients showed well differentiated adenocarcinomas, while 4 patients showed poorly differentiated adenocarcinomas (including one signet ring cell carcinoma). Cancerous and non-cancerous areas were observed after double staining with 0.05% crystal violet and 0.1% methylene blue. The endocytoscopic images obtained were evaluated by an expert endoscopist and an expert pathologist without knowledge of patient clinical data, and endocytoscopic and histopathological diagnoses were compared. RESULTS: The endocytoscopic images of the cancerous area were assessed as evaluable in 25 (83.3%) and 27 (90%) patients by endoscopist A and pathologist B, respectively, and those of the non-cancerous area as evaluable in 28 (93.3%) and 23 (76.7%) patients by the endoscopist and pathologist, respectively. The sensitivity, specificity, and diagnostic accuracy of gastric cancer diagnosis using evaluable endocytoscopic images were 88.0% and 92.9%, and 90.6% by endoscopist A, and 88.9% and 91.3%, and 90.0% by pathologist B, respectively. Evaluation of the diagnostic concordance rate between the endoscopist and the pathologist by inter-observer agreement calculation revealed no significant difference between the two observers. The inter-observer agreement (κ-value) for endocytoscopic diagnosis was 0.745. CONCLUSION: Endocytoscopy is useful for the differentiation of cancerous from non-cancerous gastric mucosa, making it a promising tool for virtual biopsy.

Risk factors for rebleeding and risk-based follow-up of obscure gastrointestinal bleeding after its initial diagnosis.

Capsule endoscopy (CE) and double-balloon endoscopy (DBE) have revolutionized the diagnosis and treatment of obscure gastrointestinal bleeding (OGIB). Although CE and DBE provide access to the small bowel and OGIB can be effectively treated by the identification of specific bleeding lesions, some patients experience rebleeding after small bowel investigation. There are no definite algorithms to determine the best follow-up period for patients with OGIB. The purpose of this study was to investigate the long-term outcomes and risk factors for rebleeding and to develop a follow-up strategy for patients with overt OGIB. Among 386 patients who underwent CE for OGIB at Nagoya University Hospital between June 2004 and December 2015, 318 patients with overt OGIB were enrolled in this retrospective study. The clinical characteristics and risk factors for rebleeding were analyzed, and a predictive model for the same was developed. Rebleeding occurred in 45 patients (14.2%) during a median follow-up period of 16.8 months. Multivariable regression analysis identified the following factors as significant independent predictors of rebleeding:vascular lesions seen during CE, transfusion requirement, and patients aged ≥60 years. The predictive model for rebleeding was developed using these factors to identify patients who had a high risk of rebleeding and to provide useful information to physicians in clinical practice. The C-statistic of the predictive model was 0.698. A risk-based approach to follow-up patients with OGIB can help clinicians determine a follow-up period for patients after small bowel investigation.

Combinational use of lipid-based reagents for efficient transfection of primary fibroblasts and hepatoblasts.

Commercially available lipid-based transfection reagents are widely used to deliver DNA to cells. However, these lipid-based transfection reagents show poor gene transfer efficiency in primary cells. Here, we demonstrate a simple method to improve gene transfer efficiency in primary fibroblasts and hepatoblasts using a combination of lipid-based transfection reagents. Our data show that combined use of Lipofectamine LTX and FuGENE HD increases the efficiency of gene transfer compared with the use of either reagent alone, and this combination achieves the best result of any pairwise combination of Lipofectamine LTX, FuGENE HD, TransFectin, and Fibroblast Transfection Reagent.

Inhibition of KDM4A activity as a strategy to suppress interleukin-6 production and attenuate colitis induction.

4-Chloro-7-nitro-2,1,3-benzoxadiazole (NBD-Cl) functions as a hapten and fluoresces upon binding to proteins. Therefore, fluorescence visualization of hapten-proteins is a feature of the colitis induced by NBD-Cl. Using this colitis model, we located activated fibroblasts in the vicinity of hapten-proteins upon colitis induction and observed interleukin (IL)-6 production in the activated fibroblasts. We screened herbal ingredients using primary fibroblasts stimulated with tumor necrosis factor α (TNF-α) and found the suppressive action of Atractylodin on IL-6 production. Under TNF-α stimulation, Atractylodin induced the tri-methylation of histone H3 at lysine residue 9, which impaired the binding between NF-κB and the IL-6 promoter on the genomic DNA. Atractylodin inhibited KDM4A but not KDM6A activity. Atractylodin administration attenuated colitis induction. The KDM4A inhibitor ML324 showed similar actions on IL-6 production and colitis induction. We propose the inhibition of KDM4A activity as a strategy to suppress IL-6 production and attenuate colitis induction.

Azathioprine is essential following cyclosporine for patients with steroid-refractory ulcerative colitis.

AIM: To evaluate long-term prognosis following cyclosporine treatment by examining the rate of surgery avoidance among cyclosporine responders. METHODS: We retrospectively reviewed clinical records for 29 patients diagnosed with severe steroid-refractory ulcerative colitis in our hospital from August 1997 to August 2008 and treated with cyclosporine by continuous intravenous infusion. All patients were treated with intravenous corticosteroids for more than 5 d prior to cyclosporine therapy. Administration was continued for up to 21 d under serum monitoring to maintain cyclosporine levels between 400 and 600 ng/mL. Clinical activity was assessed before and after cyclosporine therapy using the clinical activity index score, with a reduction of ≥ 5 considered to indicate a response. Among responders, we defined cases not requiring surgery for more than 5 years as exhibiting long-term efficacy of cyclosporine. Factors considered to be possibly predictive of long-term efficacy of cyclosporine were sex, age, disease duration, clinical activity index score, C-reactive protein level, hemoglobin level, disease extent, endoscopic findings, and clinical course. RESULTS: Cyclosporine was not discontinued due to side effects in any patient. Nineteen (65.5%) of 29 patients were considered responders. A statistically significant (P = 0.004) inverse association was observed between an endoscopic finding of "mucosal bleeding" and responsive cases. Fifteen (9 males, 6 females) of these 19 patients were followed for 5 years or more, of whom 9 (60%) exhibited long-term efficacy of cyclosporine. Of the 10 non-responders, 9 (90%) underwent surgery within 6 mo of cyclosporine therapy. None of the following factors had a significant impact on the long-term efficacy of cyclosporine: sex, age, duration of disease, clinical activity index score, C-reactive protein level, hemoglobin level, extent of disease, endoscopic findings, or clinical course. In contrast, a significant association was observed for maintenance therapy with azathioprine after cyclosporine therapy (P = 0.0014). CONCLUSION: Maintenance therapy with azathioprine might improve the long-term efficacy of continuously infused cyclosporine for severe steroid-refractory ulcerative colitis patients.

Usefulness of Helicobacter pylori eradication for precancerous lesions of the gastric remnant.

BACKGROUND AND AIM: Secondary stomach cancer in lesions of the remnant stomach occurs relatively soon after distal gastrectomy using the Billroth I reconstruction procedure. Prophylactic eradication of Helicobacter pylori after endoscopic resection of early gastric cancer should be used to prevent the development of metachronous gastric carcinoma. However, the effect of H. pylori eradication on the gastric remnant has not been clearly determined. METHODS: Eight patients who were H. pylori-positive after distal gastrectomy for primary gastric cancer underwent eradication therapy and were followed by endoscopy for 9 years. Upper gastroenteroscopy series were done before and at 1, 3, 5, 7 and 9 years after eradication, and biopsy specimens were taken from the lesser and greater curvatures, respectively. Histological changes, including chronic inflammation, activity, atrophy, and intestinal metaplasia, were evaluated using the updated Sydney system. RESULTS: Successful eradication was confirmed using the urea breath test in all eight patients. Chronic inflammation scores were improved after eradication at both the lesser (mean scores ± SD: before eradication, 2.9±0.5; 1 year after, 2.3±0.4; 3 years, 1.8±0.3; 5 years, 1.5±0.3; 7 years, 1.3±0.3; and 9 years, 1.0±0.3) and greater curvatures (before, 2.9±0.4; 1 year after, 1.9±0.3; 3 years, 1.4±0.4; 5 years, 1.3±0.3; 7 years, 1.1±0.2; and 9 years, 0.6±0.3). Atrophy scores improved more quickly after eradication than chronic inflammation scores at both the lesser (before, 2.4±0.5; 1 year after, 1.8±0.4; 3 years, 0.8±0.3; 5 years, 0.3±0.1; 7 years, 0.0; and 9 years, 0.0) and greater curvatures (before, 2.2±0.4; 1 year after, 1.3±0.3; 3 years, 0.5±0.3; 5 years, 0.0; 7 years, 0.0; and 9 years, 0.0). No secondary stomach cancers were found on endoscopy. CONCLUSIONS: Undergoing H. pylori eradication improved possible precancerous lesions of the gastric remnant among patients who had undergone distal gastrectomy. Prophylactic H. pylori eradication in the gastric remnant may be useful in preventing the development of metachronous gastric carcinoma.

Dipeptidyl peptidase-4 inhibitor anagliptin facilitates restoration of dextran sulfate sodium-induced colitis.

OBJECTIVE. Inflammatory bowel disease (IBD) is a chronic debilitating disease associated with severe damage to the intestinal mucosa. Glucagon-like peptide-2 (GLP-2) is a potent and specific gastrointestinal growth factor. GLP-2 released from enteroendocrine cells is inactivated by dipeptidyl peptidase-4 (DPP-4). The aim of this study was to examine whether the DPP-4 inhibitor anagliptin improves experimental murine colitis. MATERIAL AND METHODS. Male C57BL/6 mice aged 8 weeks were exposed to 1.5% dextran sulfate sodium (DSS) in drinking water for 7 days to induce experimental colitis. Anagliptin (0.1% in diet) was administrated from 2 days before the beginning of DSS to 7 days after the end of DSS. Changes in body weight and disease activity index were evaluated daily. Histological colitis severity, cellular proliferation and gene expression were determined in colonic tissues. RESULTS. Treatment with anagliptin clearly improved body weight loss and disease activity index in the recovery phase. Histological score in the DSS + anagliptin group at day 14 was significantly lower than that in the DSS alone group. Treatment with anagliptin increased the Ki67-positive rate at days 10 and 14, and tended to increase insulin-like growth factor-1 mRNA expression in the DSS + anagliptin group. CONCLUSION. In this model of experimental colitis, the DPP-4 inhibitor anagliptin facilitated the restoration of mucosal damage, thereby resulting in the acceleration of healing. These findings suggest a new and novel therapeutic approach for the treatment of IBD.

Importance of appropriate pharmaceutical management in pregnant women with ulcerative colitis.

BACKGROUND: Ulcerative colitis (UC) often occurs in women of childbearing age. Compared to Western countries, however, few studies have investigated the impact of UC on the progress of pregnancy in Asian populations. METHODS: We retrospectively examined 91 pregnancies in 64 patients with UC experienced at our hospital and related institutions from 1991 to 2011, focusing on the relationship between the progression of UC during pregnancy, progress of the pregnancy itself, and the treatment of UC. RESULTS: In 80 of 91 pregnancies the patient had already been diagnosed with UC at the time she became pregnant, of whom 31 (38.8%) experienced exacerbation during pregnancy. Regarding severity, moderate or severe active-stage disease during pregnancy was seen in 13.7% of those who had been in remission at the onset of pregnancy versus 58.6% of those who had been in the active stage at onset (OR 8.9: 95%CI 3.0~26.4; P<0.01). The incidence of miscarriage or abortion was 9.8% in pregnancies in which UC was in remission at onset versus 31% in those in which it was in the active stage at onset (OR 4.1: 95%CI 1.2~13.9; P=0.02). Among patients, 62.5% were receiving pharmaceutical treatment at onset of pregnancy. Exacerbation during pregnancy occurred in 26.5% of the group who continued to receive the same treatment during pregnancy versus 56.3% of those with a dose decrease or discontinuation after onset (OR 3.6: 95%CI 1.0~12.4; P=0.04). CONCLUSIONS: UC patients wishing to conceive should do so when in remission and continue appropriate pharmaceutical treatment during pregnancy.

Hepatic portal venous gas following colonoscopy in a patient with Crohn's disease.

Hepatic portal venous gas is a rare condition that occurs when intraluminal gas or gas produced by intestinal bacteria enters the portal venous circulation. It has recently been recognized as a rare complication of colon procedures by endoscopy or barium enema. Given the frequency of these procedures in patients with inflammatory bowel disease, hepatic portal venous gas may occur more frequently in these patients than previously reported. Here, we report a woman with Crohn's disease who developed hepatic portal venous gas following colonoscopy who was treated with conservative therapy.