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Background Adenoma detection rate (ADR) is an important indicator of colonoscopy quality and colorectal cancer incidence. Both linked-color imaging (LCI) with artificial intelligence (LCA) and LCI alone increase adenoma detection during colonoscopy, although it remains unclear whether one modality is superior. This study compared ADR between LCA and LCI alone, including according to endoscopists' experience (experts and trainees) and polyp size. Methods Patients undergoing colonoscopy for positive fecal immunochemical tests, follow-up of colon polyps, and abdominal symptoms at a single institution were randomly assigned to the LCA or LCI group. ADR, adenoma per colonoscopy (APC), cecal intubation time, withdrawal time, number of adenomas per location, and adenoma size were compared. Results The LCA (n=400) and LCI (n=400) groups showed comparable cecal intubation and withdrawal times. The LCA group showed a significantly higher ADR (58.8% vs. 43.5%; P<0.001) and mean (95%CI) APC (1.31 [1.15 to 1.47] vs. 0.94 [0.80 to 1.07]; P<0.001), particularly in the ascending colon (0.30 [0.24 to 0.36] vs. 0.20 [0.15 to 0.25]; P=0.02). Total number of nonpolypoid-type adenomas was also significantly higher in the LCA group (0.15 [0.09 to 0.20] vs. 0.08 [0.05 to 0.10]; P=0.02). Small polyps (≤5, 6–9mm) were detected significantly more frequently in the LCA group (0.75 [0.64 to 0.86] vs. 0.48 [0.40 to 0.57], P<0.001 and 0.34 [0.26 to 0.41] vs. 0.24 [0.18 to 0.29], P=0.04, respectively). In both groups, ADR was not significantly different between experts and trainees. Conclusions LCA was significantly superior to LCI alone in terms of ADR. [ABSTRACT FROM AUTHOR]

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Background and Aim: This study aimed to compare the mean number of adenomas in patients undergoing Endo‐wing‐assisted colonoscopy (EAC) and transparent hood‐assisted colonoscopy (TAC). Methods: Patients undergoing colonoscopy for positive fecal immunochemical tests, colon polyp surveillance, and evaluation of abdominal symptoms at a single institution were randomly assigned to the EAC or TAC group. The mean number of adenomas per patient, adenoma detection rate, cecal intubation time, withdrawal time, mean number of adenomas per location, and adenoma size were compared. Results: Overall, 800 patients were enrolled. The EAC and TAC groups comprised 372 and 393 patients, respectively. The groups did not significantly differ with respect to cecal intubation and withdrawal times. The mean number of adenomas per patient was significantly higher in the EAC group (1.13 vs 0.90, P = 0.04), particularly in the sigmoid colon (0.54 [201/372] vs 0.38 [149/393], P = 0.04). The adenoma detection rates were 48.1% and 45.0% in the EAC and TAC groups, respectively, albeit without significant difference between the two groups (P = 0.393). The total number of sessile‐type adenomas (0.73 [270/372] vs 0.47 [183/393], P < 0.0001) and small polyps (≤ 5 mm) (0.53 [198/372] vs 0.41 [159/393], P = 0.016) was significantly higher in the EAC group. Conclusion: Endo‐wing‐assisted colonoscopy is significantly superior to TAC in terms of the mean number of adenomas per patient. [ABSTRACT FROM AUTHOR]

Background: Yeasts are a type of fungi thought to have probiotic functions. In this study, we isolated a novel probiotic yeast (Zygosaccharomyces sapae strain I-6) from Miso (a traditional Japanese fermented food). We examined its effects on phenotypic changes in intestinal dendritic cells (DCs), and evaluated its anti-inflammatory effects in dextran sulfate sodium (DSS)-induced colitis.Methods: A single colony was selected from homogenized Miso, based on its ability to produce interleukin (IL)-10 in CD11c+ bone marrow DCs (BMDCs) in vitro. The anti-inflammatory effects of strain I-6 on CD11c+ BMDCs and CD11c+ CD103+ DCs were analyzed in mouse mesenteric lymph nodes in vitro and in a DSS mouse model.Results: The IL-10 concentrations in the co-culture BMDC supernatants treated with I-6 were dramatically higher than in those treated with Saccharomyces cerevisiae (Sc). IL-10 production is mediated by both TLR2 and Dectin-1. β-Glucan extracted from I-6 also induced higher levels of IL-10 production in BMDCs than β-glucan from Sc. The number of mesenteric lymph node CD11c+ CD103+ DCs was significantly increased by I-6 administration, compared with Sc administration. Strain I-6 showed strong anti-inflammatory effects on DSS-induced colitis compared to Sc. Moreover, the adoptive transfer of I-6-treated BMDCs showed anti-inflammatory effects on DSS-induced colitis in mice without oral administration of I-6 cells.Conclusions: Strain I-6 induced phenotypic changes in intestinal CD11c+ DCs characterized by high IL-10 production and exerted strong anti-inflammatory effects on DSS-induced colitis. Traditional Japanese fermented foods may be a valuable source of probiotic yeasts for effective IBD therapy and treatment. [ABSTRACT FROM AUTHOR]

Background: We isolated two novel probiotics strains (s193 and s292) from Funazushi, which is a traditional Japanese fermented food, and evaluated its effects on DSS-induced colitis to determine the possible underlying mechanisms.Methods: A single colony from homogenized Funazushi was isolated by its ability to suppress TNF-α in RAW 264.7. Effect of probiotics on colonic inflammation induced by DSS was evaluated. Effect of probiotics on Treg induction by CD11c+ dendritic cells (DCs) of MLNs were analyzed.Results: Two novel probiotics strains classified into the genus Lactobacillus were isolated (s193 and s292), and those strains showed stronger anti-inflammatory effects on DSS-induced colitis than those of L. gasseri isolated from the gut. mRNA expression β8 integrin in CD11c+DCs of MLNs and the number of Tregs in the large intestine were significantly increased by s193 and s292 administration compared with L. gasseri administration. Bone marrow DCs treated with s193 and s292 highly increased β8 integrin, and those cells strongly induced differentiation of CD4+ T cells into Tregs. Differentiation of Tregs was remarkably inhibited by anti-β8 integrin antibody treatment.Conclusions: Strains s193 and s292 demonstrate strong anti-inflammatory effects on DSS-induced colitis through induction of β8 integrin expression on DCs. Our results suggested that Japanese traditional fermented foods are valuable sources for probiotics that are effective for IBD therapy and treatment. [ABSTRACT FROM AUTHOR]

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Fatty acids in our daily diet are broadly classified into cis and trans fatty acids ( TFAs). TFAs are formed during the manufacturing process of hydrogenated vegetable oils such as margarine. Modern diets such as deep-fried products, frozen foods, and packaged snacks commonly include large quantities of margarine containing TFAs. Although an increased report in the effects of the diet containing TFAs on a risk factor of metabolic syndrome, diabetes mellitus, and coronary heart disease has been observed in the recent years, influence on intestinal inflammation remains unknown. This review describes pro-inflammatory effects of TFAs in our diary diet on various systemic disorders and also discusses a possible role of TFAs on gut inflammation. [ABSTRACT FROM AUTHOR]

Although beneficial roles of probiotics for inflammatory bowel diseases have been reported, their direct action on immune cells has not been elucidated. In this study, we investigated how three species of Bifidobacterium and Enterococcus faecalis differentially modulate production of cytokines from lipopolysaccharide (LPS)-stimulated macrophages in vitro using RAW264.7 cells. The mRNA levels of proinflammatory cytokines were remarkably increased after exposure to LPS, E. faecalis alone and LPS combined with E. faecalis. In contrast, IL-10 mRNA levels were significantly decreased after exposure to E. faecalis compared with exposure to Bifidobacterium species. When cells were exposed to Bifidobacterium species combined with LPS, mRNA levels of IL12p40 were decreased by co-culture with B. breve and B. longum, IL-1β mRNA levels were decreased by B. breve and B. adorescentis and TNF-α mRNA levels were decreased by B. adolescentis compared with LPS alone. The three species of Bifidobacterium significantly inhibited phosphorylation of IκB-α induced by LPS. The mRNA levels of SOCS1 and SOCS3 were increased by exposure to LPS alone; however, the mRNA levels of SOCS1 or SOCS3 were increased more by exposure to Bifidobacterium species combined with LPS. Conversely, E. faecalis combined with LPS induced significantly lower levels of SOCS mRNA than those induced by Bifidobacterium species combined with LPS. These results indicated that certain species of genus Bifidobacterium could negatively modulate mRNA levels of proinflammatory cytokines produced from LPS-stimulated RAW264.7 cells, which is possibly related to inhibition of IκB-α phosphorylation and stimulation of SOCS signalling. [ABSTRACT FROM AUTHOR]

Ethanol may cause an increase in sinusoidal pressure accompanied by portal hypertension. Hepatic stellate cells (HSCs) located in hepatic sinusoids may therefore be frequently exposed to dual stimulations of mechanical pressure and ethanol exposure in alcoholic liver injury. In this study, the effects of pressure loading and ethanol exposure on activation of rat cultured HSCs were investigated using an in vitro pressure-inducing apparatus. HSCs were cultured in media containing ethanol (0–100 mM) under different pressures (1–40 mmHg). Morphological changes and migration index were determined. We also determined the expression levels of α-smooth muscle actin (α-SMA) and mitogen-activated protein kinases (MAPKs) by Western blot analysis and the level of collagen IV and transforming growth factor β1 (TGF-β1) by ELISA. Pressure loading alone induced up-regulation of α-SMA via the extracellular signal-regulated kinases 1 and 2 (ERK1/2) and c-jun N-terminal kinase (JNK) signaling pathways, prolonged extension of marginal length, and increased production of collagen IV. In contrast, ethanol exposure alone increased only extension of marginal length and cell migration. Dual stimulations of pressure loading and ethanol exposure enhanced the production of TGF-β1 and migration index. The TGF-β1-dependent p38 MAPK pathway may operate for production of extracellular matrix (ECM) or enhanced migration in the case of dual stimulations. In conclusion, static pressure loading is an important factor directly accelerating the activation of HSCs. Although increased sinusoidal pressure and ethanol exposure might differentially modulate HSC activation, both stimuli are involved in an additive manner in some situations. J. Cell. Physiol. 215: 472–480, 2008. © 2007 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Objective: Although monocyte infiltration is an important aspect of the host response to tumor growth, the mechanisms of recruitment and their impact on tumor growth are still unknown. The authors studied monocyte-endothelial interaction and the effect of chemokine CCL2 in orthotopic mouse pancreatic cancer. Methods: The rolling and adhesion of labeled monocytes in peritumoral and intratumoral areas were assessed by using an intravital microscope. Further, the effects of intratumoral injection or superfusion of CCL2 on in situ recruitment of monocytes and other immune cells and adhesion molecules were investigated. Results: More monocytes were recruited in the peritumoral area than in the intratumoral area with increased vascular interaction, and the effect was more apparent by intratumoral CCL2 injection than superfusion. In both CCL2-treated groups infiltration of CD11b+, CD68+, and CD4+ cells were increased, but the magnitude of increase was larger in intratumoral injection. Quantitative RT-PCR for the tumor tissue revealed that ICAM-1 expression was increased by the injection of CCL2. Conclusion: These results show intratumoral injection of CCL2 induces effective interaction between monocytes and endothelial cells in the peritumoral area of pancreatic cancer accompanied by the upregulation of ICAM-1 and may possibly become a tool for immunotherapy by promoting the infiltration of immune cells in cancers. [ABSTRACT FROM AUTHOR]

Background. Although dendritic cells (DCs) play significant roles in intestinal immune responses, little is known regarding the direct effects of luminal foods on DC functions in the intestinal mucosa. In this study, we examined the effects of fatty acids (FAs) with various chain length on the phagocytic function, antigen presentation, and chemotaxis of intestinal DCs. Methods. DCs obtained from the thoracic duct lymph of mesenteric lymphadenectomized rats were cultured with long [arachidonic acid (AA) or oleic acid] or medium (octanoic acid) chain FAs with interleukin-4 and granulocyte macrophage-colony stimulating factor. Tumor necrosis factor-a was added in the maturation group. Phagocytic function was examined by the intake of fluorescent microbeads. The expression of cell surface molecules was determined by immunocytochemistry or fluorescence-activated cell sorting (FACS). Antigen presentation ability was evaluated by coincubating keyhole limpet hemocyanin (KLH)-sensitized spleen lymphocytes and KLH-pulsed DCs. Migratory ability of DCs toward the chemokines CC chemokine ligand (CCL) 20 and CCL21 was also assessed. Results. There was a maturation-induced decrease in phagocytic function, and an increased expression of major histocompatibility complex (MHC) class II molecules. Exposure of DCs to both long- and medium-chain FAs maintained phagocytic ability. The expression of MHC class II molecules was significantly suppressed only by long-chain FAs. The expression of costimulatory factors was suppressed only by AA. Long- but not medium-chain FAs suppressed the antigen presentation ability of DCs induced by maturation. Chemotactic ability of mature DCs toward CCL21 was abrogated only by long-chain FAs. Conclusions. The data suggest that intraluminal exposure to long- and medium-chain FAs may differentially modulate the immune functions of intestinal DCs. [ABSTRACT FROM AUTHOR]

Abstract: Nociceptin/orphanin (Noc/oFQ), endogenous agonist for nociceptin receptor (NOR), is thought to be a stimulator of neurogenic inflammation. We investigated the possible role of Noc/oFQ in the development of colitis using NOR-deficient mice treated with dextran sulfate sodium (DSS). Colitis was significantly improved in NOR-deficient mice against wild-type mice. Expression level of mucosal addressin cell adhesion molecule-1 (MAdCAM-1) and infiltrating cells also significantly decreased in NOR-deficient mice against wild-type mice. Nociceptin expression increased in wild-type mice after DSS treatment. These results suggest stimulation by Noc/oFQ deteriorates colonic inflammation via up-regulation of adhesion molecule. [Copyright &y& Elsevier]

Objective: Although the appendix is recognized as an inductive site of intestinal inflammation, lymphocyte migration to lymphoid tissues of the appendix has not been chracterized. The authors investigated if there are specific features in T-lymphocyte adhesion to microvessels of the appendix compard to mouse Peyer's patches (PPs). Methods: T-lymphocyte interaction with postcapillary venules (PCVs) of lymph follicles of the appendix and PPs was observed using an intravital microscope. Antibodies against ICAM-1, MAdCAM-1, or anti-L-selectin were administered prior to lymphocyte administration, and in some experiments CCR7 on T-lymphocytes was desensitized by excess CCL21. Results: The number of adhered T-lymphocytes reached the maximum value earlier in PCVs of PPs than in those of the appendix. T-lymphocyte adherence was significantly inhibited by anti-MAdCAM-1 at either the appendix or PPs, but adherence in the appendix was also significantly inhibited by anti-ICAM-1, suggesting a dependency on ICAM-1 in the appendix. Histologically, there was a signfiicant ICAM-1 expression in the appendix. Desensitization of CCR7 suppressed T0cell adhesion in PCVs of the appendix and PPs to the same extent. Conclusion: ICAM-1 appeared to be more important in T-lymphocyte sticking in PCVs of the appendix compared with intestinal PPs, while MAdCAM-1 and CCR7 were shown to play important roles in T-lymphocyte adherence in all sites. [ABSTRACT FROM AUTHOR]

Gut-associated lymphoid tissue is the major inductive site of the mucosal immune system, which is functionally independent of the systemic immune system. Both the amount and type of dietary fat modulate intestinal immune function. Absorption of long-chain fatty acids stimulates lymphocyte flux and lymphocyte blastogenesis in intestinal lymphatics. Long-chain fatty acid absorption also significantly enhances migration of T lymphocytes to Peyer’s patches, possibly due to up-regulation of adhesion molecules, such as α4-integrin and L-selectin. Lipoproteins are involved in stimulation of lymphocyte function by both receptor-dependent and independent mechanisms. However, unsaturated fatty acids at higher concentrations have a suppressive effect on cell-mediated immunity via eicosanoid release, receptor affinity changes or interactions with intracellular signal transduction. Fat absorption also influences various other cells in the intestinal mucosa: increased cytokine release from intestinal epithelial cells follows long-chain fatty acid absorption. In Crohn’s disease, elemental diets and total parenteral nutrition often induce remission, possibly by reducing antigenic load on activated immune cells in the intestine and, thus, down-regulating hyperreactive CD4 cells. Dietary oleic acid supplements caused an immunological reversal effect in the intestinal immune system of animals fed an elemental diet. An excess of long-chain fatty acids in an elemental diet, therefore, may negate its beneficial effect on gut-associated lymphoid tissues in Crohn’s disease. In contrast, supplemental dietary fish oil apparently tends to prevent relapse of Crohn’s disease. Because dietary fat intake is closely associated with immunological function of the intestinal mucosa, careful manipulation of dietary fat can be important in management of this disease. [ABSTRACT FROM AUTHOR]

Investigates the endotoxins stimulation of lymphocytes-endothelial interactions in rat intestinal Peyer's patches and villus mucosa. Control of recruitment of lymphocytes in gut-associated tissues; Migration of fluorescence-labeled T lymphocytes in rat's intestinal microvessels; Heterogeneity of lymphocyte-endothelial cell interactions.

Investigates the effect of endotoxin on lymphocyte-endothelial interactions in rat intestinal Peyer's patches and villus mucosa. Red blood cells velocity and shear rates in mesenteric venules; Influence of in vitro pretreatment of lymphocytes with MAb CL26 on lymphocyte sticking in Peyer's patches.

The article focuses on the role of TNF-alpha in ischemic disease of mesenteric venous systems. Acute intestinal ischemia and infarction can result from impaired blood flow within the mesenteric arterial or venous systems and are most often caused by thrombotic or embolic disease. Mesenteric venous thrombosis can be the result of primary hypercoagulable disorders or can be secondary to drugs, portal hypertension, paraneoplastic states, or an inflammatory abdominal process. Treatment of 20min venous occlusion caused significant increase of intestinal mucosal apoptotic injury that was investigated by mucosal DNA fragmentation, DNA ladder patterns, and TUNEL-positive intestinal epithelial cells.

Background: Hospitalization for ulcerative colitis (UC) is potentially life-threatening. Severe disease in the Japanese criteria which modifies the Truelove–Witts' criteria might encompass more fulminant cases than the definition for acute severe UC. However, few studies have investigated the predictive factors for clinical remission (CR) after medical treatments for severe hospitalized patients by Japanese criteria. Methods: Medical treatment selection, CR rates, and factors contributing to CR on day 14 were assessed in severe patients by Japanese criteria. We also investigated whether the reduction rate in patient-reported outcome 2 (PRO2) on day 3 could predict short-term prognosis. Results: Eighty-five severe hospitalized patients were selected. Corticosteroids, tacrolimus, and infliximab were mainly selected as first-line treatments (76/85; 89.4%). The CR rates on day 14 were 26.8%, 21.4%, and 33.3% in patients receiving corticosteroids, tacrolimus, and infliximab, respectively. Extensive disease (odds ratio [OR] 0.022; 95% confidence interval [CI] 0.002–0.198), higher PRO2 (OR 0.306; 95% CI 0.144–0.821), and higher reduction rate in PRO2 on day 3 (OR 1.047; 95% CI 1.019–1.075) were independent factors predicting CR on day 14. If the cutoff value for the reduction rate in PRO2 on day 3 was 18.3%, sensitivity was 0.714 and specificity was 0.731 to predict CR on day 14. A higher reduction rate in PRO2 on day 3 (OR 0.922; 95% CI 0.853–0.995) was a negative factor to predict surgery within 28 days. Conclusions: Tacrolimus and infliximab in addition to corticosteroids were used as first-line treatment in severe hospitalized patients. PRO2 on day 3 is a useful marker for switching to second-line therapy or colectomy. [ABSTRACT FROM AUTHOR]

Background: This multicenter observational cohort study aimed to evaluate the utilization and short-term efficacy of advanced therapy (AT) in hospitalized patients with acute severe ulcerative colitis (ASUC). Methods: In total, 221 patients with ASUC were enrolled between August 2020 and July 2021. The primary endpoint was clinical remission (CR, defined as a patient-reported outcome score < 2 with no blood in the stool) rate on Day 7 and 14 in hospitalized patients who received corticosteroids (CS) and AT. Results: Among patients with ASUC, 120 and 101 patients received CS or any AT as first-line treatment, respectively. The CR rates on Day 7 and 14 were 22.5% and 35.0%, respectively, in hospitalized patients who received CS as first-line treatment. Most patients who used ATs had CS-dependent or frequent recurrences. Eight different ATs (apheresis, tacrolimus, infliximab, golimumab, tofacitinib, vedolizumab, ustekinumab, and cyclosporine) were used as first-line treatment in patients with ASUC, and the CR rates on Day 7 and 14 were 16.8% and 29.7%, respectively. Twenty-five patients received the second ATs after hospitalizations, and the CR rates on Day 7 and 14 were 0% and 12%, respectively. The CR rates on Day 14 were significantly higher in patients who changed to AT than in those whose dose of CS increased (34.0% vs 10.7%, p = 0.020) among patients who had already used CS before hospitalization. Conclusion: Most first-use ATs were effective for patients with ASUC, while second-use ATs might have had limited benefits in inducing CR. These findings may contribute to considerations for the management of hospitalized patients. [ABSTRACT FROM AUTHOR]

Background and Aim: The study of the impact of environmental factors during pregnancy on fetal development has so far been focused primarily on those negatively affecting human health; however, little is known about the effects of probiotic treatment during pregnancy on inflammatory bowel diseases (IBD). In this study, we investigated whether oral administration of heat‐killed probiotics isolated from fermented foods decreased the vulnerability of offspring to IBD. Methods: Probiotics were administered to the pregnant mice until the birth of pups, after which the parent mice were maintained with autoclaved water. Partial pups were evaluated for dextran sodium sulfate‐induced colitis. The influence of CD11c+ CD103+ dendritic cells (DCs) and regulatory T cells (Tregs) in mesenteric lymph nodes of parent mice and their pups was analyzed. Results: Oral administration of heat‐killed probiotics to pregnant dams significantly decreased inflammation induced by dextran sodium sulfate in pups. Probiotic treatment increased the number of CD103+ DCs, and the expression of β8‐integrin in CD103+ DCs and Tregs in mesenteric lymph nodes, not only in dams themselves but also in their offspring. Conclusions: Oral administration of probiotics during gestation induced transgenerational immunomodulatory effects on the gut‐associated immune system and resilience to experimental colitis in the offspring. Our results suggest that consumption of fermented foods during pregnancy can be effective in preventing inflammatory diseases such as IBD beyond generation. [ABSTRACT FROM AUTHOR]

Few models have described a chronic food allergy with morphological changes in the intestinal mucosa. Here we established an ovalbumin (OVA)-induced, cell-mediated, allergic rat model and examined lymphocyte migration in the gut. Brown Norway rats were intraperitoneally sensitized to OVA and then given 10 mg OVA/day by gastric intubation for 6 wk. Lymphocyte subsets and adhesion molecules were examined immunohistochemically, and the migration of T lymphocytes to microvessels of Peyer's patches and villus mucosa was observed by using an intravital microscope. Serum OVA-specific IgG and IgE levels were increased in animals repeatedly exposed to OVA. Significant villus atrophy and increased crypt depth was accompanied by increased infiltration of T lymphocytes in the small intestinal mucosa of the group given OVA. Expression of rat mast cell protease II and of mucosal addressin cell adhesion molecule-1 (MAdCAM-1) was also increased in these groups. The administration of anti-MAdCAM-1 antibody significantly attenuated the OVA-induced changes in the mucosal architecture and in CD4 T lymphocyte infiltration. Intravital observation demonstrated that in rats with a chronic allergy, T lymphocytes significantly accumulated in villus microvessels as well as in Peyer's patches via a MAdCAM-l-dependent process. Our model of chronic food allergy revealed that lymphocyte migration was increased with MAdCAM-1 upregulation. [ABSTRACT FROM AUTHOR]

Background and Aim: The adenoma detection rate is an important indicator of colonoscopy quality and colorectal cancer incidence. We compared the adenoma detection rates between white light imaging (WLI) and linked color imaging (LCI) colonoscopy. Methods: Patients undergoing colonoscopy for positive fecal immunochemical tests, follow‐up of colon polyps, and abdominal symptoms at three institutions were randomly assigned to the LCI or WLI groups. Mean adenoma number per patient (including based on endoscopists' experience), adenoma detection rate, cecal intubation time, withdrawal time, mean adenoma number per location, and adenoma size were compared. Results: The LCI and WLI groups comprised 494 and 501 patients, respectively. No significant differences in the cecal intubation rate (LCI vs WLI: 99.5% vs 99.4%), cecal intubation time, and withdrawal time were noted between groups. The mean adenoma number per patient was significantly higher in the LCI group than in the WLI group (1.07 vs 0.88, P = 0.04), particularly in the descending [0.12 (58/494) vs 0.07 (35/501), P = 0.01] and sigmoid colon [0.41 (201/494) vs 0.30 (149/501), P ≤ 0.001]. However, the adenoma detection rate was 47.1% in the LCI group and 46.9% in the WLI group, with no significant difference (P = 0.93). The total number of sessile‐type adenomas was significantly higher in the LCI group than in the WLI group (346/494 vs 278/501, P = 0.04). As for polyp size, small polyps (≤ 5 mm) were detected at a significantly higher rate in the LCI group (271/494 vs 336/501, P = 0.04). Conclusion: Linked color imaging is significantly superior to WLI in terms of mean adenoma number per patient. [ABSTRACT FROM AUTHOR]

Alterations in immunological defense in the gut may lead to the bacterial infection that is frequently associated with cirrhosis of the liver. The aim of this study was to investigate the changes in distribution and function of intestinal intraepithelial lymphocytes (IELs) in relation to intestinal barrier dysfunction in experimental cirrhosis. Cirrhosis was induced in mice by treatment with carbon tetrachloride (CCl4) intraperitoneally with 5% alcohol in drinking water for 12 weeks. Bacterial translocation was assessed in mesenteric lymph nodes (MLNs) by the transport of fluorescence-labeled latex beads and by bacteriological cultures. The lymphocyte subpopulation was compared in three groups (cirrhosis, alcohol alone and controls). IFN-γ production from isolated IELs was determined by ELISA after stimulation with anti-CD3 or IL-12/IL-18. The total number of IELs significantly increased in the cirrhosis and alcohol groups. There was a preferential increase in TCRγδ+CD8+ population in the alcohol group, but no change in cirrhosis. Bacterial translocation was negative in the control group, and a small number was noted in the alcohol group, whereas it was significantly noted in the cirrhosis group. Although the number of IEL was significantly increased in the cirrhosis group, their proliferative response was decreased, and IFN-γ production from each IEL was markedly diminished in either stimulation by anti-CD3 or IL-12/IL-18. These changes were more remarkable in the cirrhosis group than in the alcohol group. In conclusion, bacterial translocation due to intestinal barrier dysfunction in cirrhosis may be closely correlated with the alteration of the immune function in IELs. [Copyright &y& Elsevier]

Intravital microscopy coupled with chronic animal window models has provided stunning insight into tumor pathophysiology, including gene expression, angiogenesis, cell adhesion and migration, vascular, interstitial and lymphatic transport, metabolic microenvironment and drug delivery. However, the findings to date have been limited to the tumor surface (< 150 μm). Here, we show that the multiphoton laser-scanning microscope can provide high three-dimensional resolution of gene expression and function in deeper regions of tumors. These insights could be critical to the development of novel therapeutics that target not only the tumor surface, but also internal regions. [ABSTRACT FROM AUTHOR]

Background and Aims: Laser endoscopy involves blue laser imaging in bright mode (BLI‐bright). Linked color imaging (LCI) is superior to white light imaging (WLI) for detecting gastric cancers. This study aimed to detect gastric cancers on screening endoscopy using not only WLI but also BLI‐bright and LCI in patients with atrophic gastritis. Patients and Methods: A total of 500 patients with atrophic gastritis undergoing screening esophagogastroduodenoscopy were included. The gastric lumen was observed in the WLI mode, followed by the LCI and BLI‐bright modes. When gastric neoplasms were suspected, the mode was changed to WLI, and we sprayed indigo carmine. Finally, biopsy specimens were taken for those lesions and pathological diagnosis was made. We compared the size, morphology, and color of gastric neoplasms found by the first WLI mode and those detected by only the LCI mode or BLI‐bright mode. Results: We detected 16 gastric neoplasms (3.2%), of which 13 were early gastric cancers (EGCs) and three were gastric adenomas. Ten EGCs and two gastric adenomas (75%) were detected by the first WLI mode; three EGCs and one gastric adenoma (25%) were missed by the first WLI mode and were detected by the LCI mode or BLI‐bright mode. All were less than 1 cm in diameter and were reddish. Mean diameter of the lesions was significantly less for LCI‐detected or BLI‐bright‐detected lesions than for WLI‐detected lesions (7.8 vs 21.2 mm). Conclusions: Laser endoscopy is useful for detecting EGCs by LCI for patients with atrophic gastritis. [ABSTRACT FROM AUTHOR]

Background and Aim: Transparent hood‐assisted colonoscopy (TAC) has been reported to improve the cecal insertion rate and adenoma detection rate (ADR). An endoscopic cap (Endocuff) with two rows of soft wings was recently developed to improve ADR, by flattening the mucosal folds during withdrawal. This randomized prospective control study aimed to compare ADR between Endocuff‐assisted colonoscopy (EAC) and TAC. Methods: A total of 513 patients undergoing colon adenoma screening were included. EAC was performed in 256 patients and TAC in 260 patients. Cecal intubation rate, cecal intubation time, ADR, and mean adenoma number per patient (MAP) were investigated in both groups (clinical trial registration: UMIN000016278). Results: We excluded six patients in the EAC group and two patients in the TAC group because of colonic stenosis due to colonic adenocarcinomas. Finally, 250 patients (151 men/99 women, median age 62.1 years) were assigned to EAC and 258 patients (165 men/93 women, median age 64.3 years) were assigned to TAC. There were no significant differences in cecal intubation rate, intubation time, withdrawal time, and cleanliness score between groups. The ADR was 50.8% in EAC and 52.7% in TAC, with no significant difference (P = 0.666). The MAP was 1.35 in EAC and 1.20 in TAC, with no significant difference (P = 0.126). However, The MAP of diminutive adenomas (< 5 mm) tended to be higher in EAC than in TAC (P = 0.077). There was no significant difference in MAP in each segment between groups. Conclusions: Endocuff‐assisted colonoscopy might be equivalent to TAC in cecal intubation time, ADR, and MAP. [ABSTRACT FROM AUTHOR]

Background: Although the incidence of inflammatory bowel diseases (IBD) in Japan has increased, the prevalence of celiac disease is considered very low with the lowest genetic disposition. IBD is reported as the most common comorbidity because of the high positive rate of serological celiac markers. The aim of this study was to examine the current incidence of celiac disease, especially in IBD patients in Japan, where both wheat consumption and incidence of IBD have increased. Methods: A total of 172 patients with IBD and 190 controls in Japan were screened for serum antibody of tissue transglutaminase and deaminated gliadin peptide. In sero-positive patients, HLA testing and upper gastrointestinal endoscopy with duodenal biopsy was performed. Some of the sero-positive patients started a gluten-restricted or unrestricted diet, and serological change was determined. Results: The positivity of both serum antibodies was significantly higher in IBD and correlated with disease activity. However, no biopsy-defined or HLA-defined true celiac disease was found. A decrease in serum antibody titers was observed with a gluten-restricted diet. Conclusions: Despite the increased incidence of IBD and high positivity for serum celiac antibody in Japanese IBD patients, no true-positive celiac disease was noted, suggesting the presence of gluten intolerance in these populations. [ABSTRACT FROM AUTHOR]

Microcirculation (2010) 17, 321-332. doi: 10.1111/j.1549-8719.2010.00032.x Abstract Objective: Aberrant leukocyte migration has been implicated in the pathogenesis of inflammatory bowel disease (IBD). Lemon grass is a natural herb that contains citral, which suppresses lymphocyte expression of gut homing molecules by inhibiting retinoic acid formation. We therefore hypothesized that lemon grass intake could ameliorate excess migration of leukocytes to the inflamed intestine in chronic ileitis. Methods: Migration of fluorescence-labeled T cells to microvessels in the ileal mucosa of SAMP1/Yit mice was monitored using intravital microscopy. In some mice, lemon grass solution was administered for two weeks. For evaluation of the effects on chronic ileitis, mice were treated with lemon grass for 26 weeks. Results: Surface expression of β7 and CCR9 on T lymphocytes was stronger in SAMP1/Yit mice than in AKR/J mice. Lemon grass treatment attenuated the surface expression of β7-integrin and CCR9. The number of adherent lymphocytes to microvessels in chronic inflamed ileum was significantly few when lymphocytes were isolated from lemon grass treated mice. Long-term lemon grass treatment improved ileitis in SAMP1/Yit mice, which was assessed by body weight, histological changes and the infiltration of β7-positive cells. Conclusion: Lemon grass ameliorated ileitis through decreasing lymphocyte migration by inhibiting β7-expression, suggesting its therapeutic usefulness for IBD. [ABSTRACT FROM AUTHOR]

Objective: Although enterobacteria are implicated in intestinal immune response, there has been no report on how intraluminal pathogens affect lymphocyte recruitment. The aim of this study was to determine how the presence of intestinal flora affects lymphocyte migration to intestine under physiological and lipopolysaccharide (LPS)-induced inflammatory conditions. Methods: Interaction of T-cells with ileal microvessels was monitored by using an intravital microscope in mice under germ-free (GF) and specific pathogen-free (SPF) conditions. LPS was administered into either the peritoneal cavity or duodenum before lymphocyte injection. Results: Adherence of T-cells was greater in SPF than in GF mice, indicating that the presence of enterobacteria upregulated migration under physiological conditions. Intraperitoneally administered LPS significantly increased the adherence of T-cells in both GF and SPF mice accompanied by the expression of adhesion molecules and proinflammatory cytokines. However, intraluminally administered LPS did not enhance the adherence of T-cells in SPF mice. A significant induction of increase in mRNA expression of IRAK-M, a negative regulator of TLR4 signaling, and transforming growth factor beta (TGF-beta), a regulatory cytokine, was observed in SPF mice after luminal LPS treatment. Conclusions: Tolerance to intraluminally administered LPS in the lymphocyte recruitment process was induced by enterobacteria, possibly via the induction of IRAK-M and TGF-beta. [ABSTRACT FROM AUTHOR]

Objective: Although it is known that the chemokines CXCL12 and CCL20 are expressed in the intestine, their contribution to lymphocyte homing has not been investigated in detail. The authors investigated whether the CXCL12-CXCR4 and CCL20-CCR6 systems are involved in T lymphocyte-endothelial interaction in microvessels of the small and large intestines. Methods: Labeled lamina proprial lymphocytes (LPLs) were administered to mice, and their adhesion to microvessels of normal and TNF-α -induced inflamed intestinal mucosa was observed under an intravital microscope. Antibodies against CXCL12, CCL-20, or CCL-25 were administered prior to lymphocyte administration, and in some experiments CXCR4 or CCR6 on LPLs was desensitized with an excess amount of chemokine. Results: LPLs adhered to microvessels of the ileum and colon, and TNF-α induced a significant accumulation at both sites. Blocking of the CXCL12-CXCR4 system significantly inhibited the LPL adhesion in the ileum and colon under both normal and TNF-α -treated conditions. However, blocking of the CCL20-CCR6 system significantly attenuated LPL adhesion only under a TNF-α -treated condition. There was an additive inhibitory effect on LPL adherence by CXCL12 and CCL20 blocking in TNF-α -induced inflamed intestines. There was also an additive function of the CCL25-CCR9 system in LPL accumulation in the small intestine. Conclusion: Several chemokine systems may play significant roles cooperatively in vivo in LPL adherence to microvessels of intestinal mucosa. [ABSTRACT FROM AUTHOR]

Background: Although dendritic cells (DCs) play significant roles in intestinal immune responses, little is known regarding the direct effects of luminal foods on DC functions in the intestinal mucosa. In this study, we examined the effects of fatty acids (FAs) with various chain length on the phagocytic function, antigen presentation, and chemotaxis of intestinal DCs.Methods: DCs obtained from the thoracic duct lymph of mesenteric lymphadenectomized rats were cultured with long [arachidonic acid (AA) or oleic acid] or medium (octanoic acid) chain FAs with interleukin-4 and granulocyte macrophage-colony stimulating factor. Tumor necrosis factor-alpha was added in the maturation group. Phagocytic function was examined by the intake of fluorescent microbeads. The expression of cell surface molecules was determined by immunocytochemistry or fluorescence-activated cell sorting (FACS). Antigen presentation ability was evaluated by coincubating keyhole limpet hemocyanin (KLH)-sensitized spleen lymphocytes and KLH-pulsed DCs. Migratory ability of DCs toward the chemokines CC chemokine ligand (CCL) 20 and CCL21 was also assessed.Results: There was a maturation-induced decrease in phagocytic function, and an increased expression of major histocompatibility complex (MHC) class II molecules. Exposure of DCs to both long- and medium-chain FAs maintained phagocytic ability. The expression of MHC class II molecules was significantly suppressed only by long-chain FAs. The expression of costimulatory factors was suppressed only by AA. Long- but not medium-chain FAs suppressed the antigen presentation ability of DCs induced by maturation. Chemotactic ability of mature DCs toward CCL21 was abrogated only by long-chain FAs.Conclusions: The data suggest that intraluminal exposure to long- and medium-chain FAs may differentially modulate the immune functions of intestinal DCs. [ABSTRACT FROM AUTHOR]

It has recently been suggested that C-C chemokines may play a role in the organ-specific homing of lymphocytes, but there is not enough in vivo evidence in intestinal mucosa. The aim of this study was to examine whether thymusexpressed chemokine (TECK)/CCL25 and its ligand CCR9 are involved in T-lymphocyte interaction with microvessels of murine intestinal mucosa. T lymphocytes from the small intestine were fluorescence labeled, and their adhesion to mucosal microvessels was observed by intravital microscopy. Lamina proprial lymphocytes (LPL) and intraepithelial lymphocytes (IEL) adhered to both the small intestine and colon, and desensitization of CCR9 with TECK/CCL25 or anti-TECK/CCL25 antibody significantly inhibited these adhesions only in small intestine. At both sites, TNF-α significantly increased LPL adhesion but not IEL adhesion. Desensitization of CCR9 or anti-TECK/CCL25 antibody also attenuated the TNF-α-induced LPL adhesion in the small intestine. Increased expression of TECK/CCL25 by TNF-α was observed in the lamina propria of small intestine. TECK/CCL25 may thus play an important role in the adherence of mucosal lymphocytes to the microvessels of the small intestine but not the colon under uninflamed as well as inflamed conditions. [ABSTRACT FROM AUTHOR]

Abstract Background and Aim: The pathogenesis of ulcerative colitis (UC) is unclear, but abnormal infiltration of T lymphocytes in the colonic mucosa has been implicated in the mucosal tissue damage. The abnormal cytokine production because of a T helper (h)1/Th2 imbalance may play an important role in continuing inflammation in the colonic mucosa. In the present study, the expression of chemokine receptor 5 (CCR5) as a Th1 marker and a chemoattractant receptor-homologs molecule expressed on Th2 cells (CRTH2) were investigated in order to analyze impaired Th1/Th2 responses in the colonic mucosa of UC patients. Methods: Tissue samples were obtained by colonic biopsies from patients with UC or colonic polyps, with informed consent. Immunohistochemical analysis was performed on periodate, lysine-paraformaldehyde-fixed serial cryostat sections using the labeled streptavidin biotin method. Monoclonal antibodies against CD4, CCR5 or CRTH2 were used as primary antibodies. The number of cells expressing CD4, CCR5 or CRTH2 per unit area was calculated by using an image analyzer. Results: In the patients with UC, the numbers of CD4- and CCR5-positive cells were significantly increased in inflamed mucosa, and appeared to be correlated with the disease activity. The infiltration of CRTH2-positive cells was predominantly observed in the mildly inflamed or the margin of inflamed mucosa of UC patients. Conclusion: There is a possibility that Th1 responses significantly occur in colonic mucosa with severe inflammation, while Th2 responses mainly occur with mild inflammation in UC patients. The Th1/Th2 imbalance in colonic mucosa may be related to the disease progression of UC. [ABSTRACT FROM AUTHOR]

Intraepithelial lymphocytes (IELs) play important roles in intestinal mucosal immunity. Although fatty acids are known to modulate the functions of immune effector cells, there has been no information about how fat exposure affects immunological function of IELs. In this study, we examined how fatty acids of various chain lengths modulate the production of interferon (IFN)-γ by IELs stimulated with T-cell receptor (TCR) or interleukin (IL)-12/IL-18. IELs isolated from the small intestine of BALB/c mice were stimulated with plate-coated anti-CD3 monoclonal antibody (mAb) or IL-12/IL-18. They were coincubated in microtiter plates for 3 days with various concentrations of fatty acid micelles. We used arachidonic acid, linoleic acid, and oleic acid as long-chain fatty acids, and used octanoic acid as a medium-chain fatty acid. IFN-γ in the supernatants were measured by ELISA, and the expression of IFN-γ mRNA in IELs was determined by RT-PCR. Significant production of IFN-γ from IELs was observed after anti-CD3 mAb stimulation. The combination of IL-12 and IL-18 induced significant levels of IFN-γ production without TCR stimulation. Increased IFN-γ mRNA was also observed after anti-CD3 or IL-12/IL-18 stimulation. Long-chain fatty acids dose-dependently inhibited the stimulated-IFN-γ production at concentrations greater than 10 μM, but the medium-chain fatty acid did not cause any significant changes in IFN-γ production. IFN-γ production from γδ IELs was very low compared with αβ IELs, however, both populations showed similar attenuating patterns when treated with long-chain fatty acids. There is a possibility that the exposure of IELs to intraluminal fatty acids significantly modifies the immune function of intestinal mucosa. [Copyright &y& Elsevier]

Relatively little is known about how recirculation of lymphocytes through the inflamed intestinal mucosa is regulated. The aim of this study was to investigate the dynamic process of T lymphocyte-endothelial cell adhesion in TNF-αchallenged murine colonic mucosa by intravital microscopy. T lymphocytes from spleen (SPL) and intestinal lamina propria (LPL) were fluorescence labeled, and their adhesion to microvessels in the colonic mucosa was observed. In TNF-α (25 µg/kg)-stimulated colonic venules, an enhanced adhesion of SPL and LPL was demonstrated, with dominant recruitment of LPLs. The magnitude of the increased LPL adhesion was more significant in the colon than in the small intestine. These T lymphocyte interactions in the colonic mucosa were significantly reduced by blocking MAbs against either mucosal addressin cell adhesion molecule-1 (MAdCAM-1), VCAM-1, α[sub 4]-integrin, or β[sub 7]-integrin but not by anti-ICAM-1. Immunohistochemistry revealed significant MAdCAM-1 expression in the lamina propria and VCAM-1 expression in the submucosa of TNF-α-treated colon. Spatial heterogeneity of MAdCAM-1 and VCAM-1 activation following TNF-α challenge may promote specific T lymphocyte recruitment in the inflamed colonic mucosa. [ABSTRACT FROM AUTHOR]

Background/Aims: Cytokine-induced neutrophil chemoattractant (CINC/gro), a member of interleukin-8 family, was found as a potent chemotactic factor for rat neutrophils. Although several chemokines have been shown to be potent regulators of T cell chemotaxis in vitro, the potential role of chemokines in T-cell migration in gut-associated lymphoid tissues has not been investigated in vivo. In the present study, the effects of CINC/gro on T-lymphocyte migration were examined in rat Peyer’s patches. Methods: T lymphocytes collected from intestinal lymph of rats were fluorescence-labeled and injected into the jugular vein. Peyer’s patches of the recipient rats were observed with intravital fluorescence microscopy and the effects of CINC/gro infusion was investigated. Lymphocyte flux in mesenteric collecting lymphatics was also observed. Results: In vivo infusion of CINC/gro significantly attenuated the initial lymphocyte interaction with postcapillary venules of Peyer’s patches. However, once these lymphocytes adhered to venules, CINC/gro treatment significantly accelerated the transendothelial migration of T lymphocytes and they also significantly increased their subsequent flux in collecting lymphatics. Conclusion: There is a possibility that CINC/gro could modulate the characteristics of T lymphocyte homing in the inflammatory sites of gut.Copyright © 2001 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Provides information on a study which examined whether endothelin (ET) is synthesized by intestinal epithelial cells and whether it affects induction of epithelial cell proliferation by interleukin-2 (IL-2). Brief review of related literature; Materials and methods; Discussions and conclusions.

Kupffer cells contribute to the important role of the liver defense mechanism through nitric oxide (NO) production. In this study, the effect of chronic ethanol administration on the ability of Kupffer cells to synthesize and release NO was investigated after stimulation with lipopolysaccharide (LPS). Male Wistar rats were chronically fed ethanol for 8 weeks according to the method described by DeCarli and Lieber et al. ( J Nutr. 91:331-336, 1967). Kupffer cells were isolated and cultured with LPS (1 μg/ml) for 24 hr. The levels of nitrite and nitrate, metabolites of NO, were determined in the culture medium. NO synthase (NOS) activity in Kupffer cells was determined by the method that measures conversion of [14C]arginine into [14C]citrul-line. In control rats, a significant increase of nitrite and nitrate levels in culture medium was observed after LPS treatment. The magnitude of this increase was significantly smaller in chronic ethanol-fed rats. When the activity of NOS was determined, inducible NOS (iNOS) activity was higher than that of constitutive NOS, and LPS administration produced a significant elevation of iNOS activity in both control and chronic ethanol-fed rats. However, the elevation of iNOS activity by LPS stimulation was diminished by chronic ethanol administration. Distribution of iNOS in Kupffer cells as determined by an immunofluorescence method using a laser scanning confocal image system showed a lower expression of iNOS in chronic ethanol-fed rats even in the presence of LPS. These results demonstrate that the excessive production of NO by increased iNOS activity in Kupffer cells is diminished by chronic ethanol administration. [ABSTRACT FROM AUTHOR]