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• Non-alcoholic fatty liver disease includes multifactorial mechanisms together with intestinal microbiota, especially obesity, metabolic syndrome. • The epithelial mucosal barrier in the colon constitutes the non-transient microbial flora. • Damage to this barrier or dysbiosis in the microbiota profile primarily affects the liver via the portal vein. • Gram-negative microorganisms are very important as a microbial profile in non-alcoholic fatty liver disease. Non-alcoholic fatty liver disease (NAFLD) is known to be the most common liver disease in the world, and there are currently no approved pharmacological treatments to prevent or treat this condition. In addition to being associated with an increased risk of hepatocellular carcinoma and cirrhosis, NAFLD has now become the leading cause of liver failure-associated transplantation. The 16S rRNA gene which conserved regions can serve as universal primer binding sites for PCR amplification of gene fragments, while hypervariable regions contain significant sequence diversity useful for prokaryotic identification purposes. 16S rRNA gene sequences can be use by researchers to identify prokaryotic taxonomy found in clinical samples. As a result of increasing microbiota studies with developing technological developments, the role of intestinal microbiota in the pathogenesis of NAFLD is revealed in an important way. In this study, it was aimed to determine the clinical prognostic importance of gut microbiota in the pathogenesis of NAFLD and to determine the microbial composition with intestinal mucosal biopsy samples in NAFLD patients. We included 20 patients diagnosed with NAFLD as a result of liver function tests, histological, ultrasonographic, biopsy evidence and 20 normal control groups created under exclusion criteria in this study. The healthy control group of the same age and gender as the patients were determined to be equal, and the age, gender, BMI, insulin resistance, AST, ALT levels of the individuals were recorded for analysis. İntestinal mucosal biopsy samples were taken from the individuals included in the study under sterile conditions. Microbial results were obtained as a result of 16S rRNA amplicon metagenomic processes. The region of approximately 1500 bp covering the V1-V9 region of the 16S rRNA gene was targeted to detect microbial diversity. The amplified regions were sequenced using next-generation sequencing. Operational Taxonomic Unit (OTU) value was obtained with bioinformatics software with the obtained sequence data. The analysis of the recorded parameters was done with the SPSS.19 statistical program. In the designed study, 16 phyla, 28 class, 56 order, 128 family, 415 genera, 1041 species microorganisms were analyzed taxonomically in a total of 40 individuals. In our study, Intestinal microbial diversity is lower in NAFLD patients compared to control group individuals. In addition, gram-negative bacteria were found to be more dominant in NAFLD patients. As a phylum, Proteobacteria increased in NAFLD group, Bacteroidetes and Actinobacteria in control group, while Firmicutes had equal distribution in both groups. BMI OR = 6.37, 95 %CI (0.39–0.40) p value was 0.001 in laboratory data, whereas Proteobacteria OR = 1.754, 95% CI (0.901–3.416), p value 0.05 in microbial profile. The 16S rRNA metagenomic study of intestinal microbiota using colonic mucosal biopsy samples in NAFLD disease was the first study in the Turkish population, and important data were obtained for other studies. In the data obtained, we think Proteobacteria, Ruminococcaceae, Escherichia coli and Bacilli are very important in both diagnostic and treatment options as a microbial profile in NAFLD. [ABSTRACT FROM AUTHOR]

Increased colonic serotonin (5-HT) level and decreased serotonin reuptake transporter (SERT) expression in irritable bowel syndrome (IBS) may contribute to diarrhea and visceral hypersensitivity. We investigated whether mucosal SERT is modulated by gut microbiota via a mast cell–prostaglandin E2 (PGE2) pathway. C57Bl/6 mice received intracolonic infusion of fecal supernatant (FS) from healthy controls or patients with diarrhea-predominant irritable bowel syndrome (IBS-D). The role of mast cells was studied in mast cell–deficient mice. Colonic organoids and/or mast cells were used for in vitro experiments. SERT expression was measured by quantitative polymerase chain reaction and Western blot. Visceromotor responses to colorectal distension and colonic transit were assessed. Intracolonic infusion of IBS-D FS in mice caused an increase in mucosal 5-HT compared with healthy control FS, accompanied by ∼50% reduction in SERT expression. Mast cell stabilizers, cyclooxygenase-2 inhibitors, and PGE2 receptor antagonist prevented SERT downregulation. Intracolonic infusion of IBS-D FS failed to reduce SERT expression in mast cell–deficient (W/Wv) mice. This response was restored by mast cell reconstitution. The downregulation of SERT expression evoked by IBS FS was prevented by lipopolysaccharide (LPS) antagonist LPS from Rhodobacter sphaeroides and a bacterial trypsin inhibitor. In vitro LPS treatment caused increased cyclooxygenase-2 expression and PGE2 release from cultured mouse mast cells. Intracolonic infusion of IBS-D FS in mice reduced colonic transit, increased fecal water content, and increased visceromotor responses to colorectal distension. Ondansetron prevented these changes. Fecal LPS acting in concert with trypsin in patients with IBS-D stimulates mucosal mast cells to release PGE2, which downregulates mucosal SERT, resulting in increased mucosal 5-HT. This may contribute to diarrhea and abdominal pain common in IBS. Dysregulation of microbial composition in the colon may result in abnormal serotonin metabolism in the colon contributing to diarrhea and abdominal pain often observed in patients with irritable bowel syndrome. [ABSTRACT FROM AUTHOR]

A 61-year-old patient underwent endoscopic exploration for anemic syndrome. His medical history revealed that he had been taking a drug based on a mixture of medicinal herbs as laxative for nine years. This product consists of anthranoid-containing laxatives as aloe, senna, rhubarb, cascara and frangula. Endoscopy revealed diffuse dark brown pigmentation throughout his colon, which is compatible with the melanosis coli (Image 1). Further, an unpigmented polyp measuring 8 mm in diameter was seen in the right colon. Macrophages laden with brownish pigment in the lamina propria, were found in all biopsies of the colon. Histopathological examination of the polyp showed a tubulovillous adenoma with low-grade dysplasia. Melanosis coli is a disease characterised by a brownish pigmentation of the colonic mucosa. It is well known that anthranoid containing laxatives, widely used for constipation, are frequently the cause. Anthraquinones have a direct toxic effect on the epithelial cells of the colon that results in the production of lipofuscin, the dark pigment seen in macrophages in melanosis coli. Long-term use of anthranoids is generally believed to be necessary to cause melanosis coli. However, it was established that this condition can develop within periods varying from only 3 to 13 months. The question if melanosis coli predisposes for colorectal neoplasia is discussed controversially. An association of melanosis coli between colorectal adenomas, but not colorectal carcinomas, is under discussion. Melanosis colis is reversible, disappearance of the pigment generally occurs within a year after a patient stops taking anthraquinone.

Background In ruminants, lower ruminal pH causes massive disruption of ruminal epithelial structure during periods of feeding high-concentrate diets. However, the influence of excessive organic fatty acids in the lumen of hindgut on the epithelial structure is unclear. In this study, twelve mid-lactating goats were randomly assigned to either a HC diet group (65% concentrate of dry matter; n = 6) or a LC diet group (35% concentrate of dry matter; n = 6) for 10 weeks. The colonic epithelial structure was detected by HE staining and transmission electron microscopy (TEM), and the apoptotic status of epithelial cells was estimated by TUNEL method and caspase activities. Results HC goats showed higher level of free lipopolysaccharide (LPS) in rumen fluid (p < 0.01) but not in colonic digesta (p > 0.05), and higher total volatile fatty acid (VFA) concentrations in rumen fluid (p < 0.05) and in colonic digesta (p < 0.01), and higher content of starch in colonic digesta (p < 0.05) compared to LC goats. HC goats demonstrated profound alterations in the colonic epithelial structure and tight junctions (TJ), apparently due to damage of the epithelium with widened TJs space and nuclear breakdown and mitochondrial, swelling. HC goats showed higher level of apoptosis in the colonic epithelium with higher proportion of TUNEL-positive apoptotic cells and increases of caspase-3 and -3/7 activities, as well as the lower ratio of bcl-2/bax mRNA expression in the colonic mucosa (p < 0.05). However, β-defense mRNA was significantly down-regulated in the colonic mucosa of HC goats compared to LC (p < 0.05). HC goats showed higher level of TJ proteins including claudin-1 and claudin-4 in the colonic mucosa than LC (p < 0.05). Neither free LPS content in the colonic digesta nor NF-k B protein expression in tissues showed significant difference between HC and LC goats (p > 0.05). Conclusions Our results reveal that long-term feeding HC diet to lactating goats causes severe damages to the colonic mucosa barrier associated with activating cells apoptosis. [ABSTRACT FROM AUTHOR]

Background Alterations of intestinal microbiota and hypersensitivity to colonic distension are two features of the irritable bowel syndrome ( IBS). However, the role of intestinal microbiota in visceral hypersensitivity of IBS patients is far to be established. The aim of our study was to determine whether the intestinal microbiota is involved in the visceral hypersensitivity in IBS. Methods The painful response to colorectal distension and colonic mucosal parameters were assessed in gnotobiotic rats. Germfree (GF) rats were inoculated with the fecal microbiota from IBS patients characterized by hypersensitivity to colorectal distension ( IBS HMA rats) or from non-hypersensitive healthy volunteers (Healthy HMA rats). Conventional rats were studied as normosensitivity control. Fecal microbial analyses were carried out in human and HMA rats fecal samples using cultural and molecular approaches. Key Results The microbial dysbiosis of the IBS gut microbiota (more sulfate-reducing bacteria and Enterobacteriaceae and less bifidobacteria) could be maintained in gnotobiotic rats. The number of abdominal contractions in response to colorectal distensions was significantly higher in IBS HMA rats than in healthy HMA rats. No difference was observed between healthy HMA and conventional rats. Colorectal compliance, epithelial paracellular permeability, and density of colonic mucosal mast cells were similar in the three groups of rats. Conclusions & Inferences We herein showed that sensitivity to colonic distension of IBS patients can be transferred to rats by the fecal microbiota. Mucosal alterations associated with microbiota transfer are not involved in this hypersensitivity. The altered IBS microbiota may have important role in the hypersensitivity characterizing IBS patients through specific bacterial metabolites. [ABSTRACT FROM AUTHOR]

Background: Colorectal cancer (CRC) which is the third most diagnosed cancer throughout the world is steadily rising in the Asian countries with the incidence rates mimicking the western counterparts. The pre-neoplastic nature of the Transitional Mucosa (TM) adjoining CRC lacks conclusive evidence so far. Pertaining to this, the study of the mucus layer, the functional component of the colonic mucosa overlying the TM is the subject of interest in this research. Methods: The normal samples were biopsied from normal subjects by colonoscopy. Ten cases of CRCs of the distal colon who underwent anterior resection were chosen for this study. Three samples were taken 2ms, 5cms and 10cms from the colorectal cancer of the distal colon in the proximal margin. These samples were processed and viewed under the scanning electron microscope (SEM) to look for the changes in the mucus layer. Results: The findings show that the changes were consistently found 2cms from the tumor and only one case showed changes up to 5cms. The statistical tests using SPSS version 18 revealed that there was no association between the surface mucus changes and the age, gender, race, site of tumor, differentiation of tumor and clinical staging of the patients. Conclusion: It was concluded that there was no correlation between the structural and functional changes of the surface mucus overlying the distal colon during carcinogenesis. Furthermore, it can be stated that the functional change may be as a result of the structural change due to a nearby tumor. [ABSTRACT FROM AUTHOR]

Grape antioxidant dietary fibre (GADF) is a grape product rich in dietary fibre and natural antioxidants. We reported previously that GADF intake reduced apoptosis and induced a pro-reducing shift in the glutathione (GSH) redox status of the rat proximal colonic mucosa. The aim of the study was to elucidate the molecular mechanisms responsible for the anti-apoptotic effect of GADF and their association with the oxidative environment of the distal colonic mucosa. The ability of GADF to modify colonic crypt cell proliferation was also investigated. Male Wistar rats (n 20) were fed with diets containing either cellulose (control group) or GADF (GADF group) as fibre for 4 weeks. GADF did not modify cell proliferation but induced a significant reduction of colonic apoptosis. The anti-apoptotic proteins Bcl-2 (B-cell lymphoma-2) and Bcl-xL (B-cell lymphoma extra large) were up-regulated in the mitochondria and down-regulated in the cytosol of the GADF mucosa, whereas the opposite was found for the pro-apoptotic protein Bax (Bcl-2-associated X protein), leading to an anti-apoptotic shift in the pattern of expression of the Bcl-2 family. Cytosolic cytochrome c and cleaved caspase-3 levels and caspase-3 activity were reduced by GADF. The modulation of the antioxidant enzyme system and the increase of the cytosolic GSH:glutathione disulfide (GSSG) ratio elicited by GADF helped to reduce oxidative damage. The cytosolic GSH:GSSG ratio was negatively related to apoptosis. These results indicate that GADF acts on the expression of the pro- and anti- apoptotic Bcl-2 proteins, attenuating the mitochondrial apoptotic pathway in the distal colonic mucosa. This effect appears to be associated with the antioxidant properties of GADF. [ABSTRACT FROM AUTHOR]

Background/Aim: Chronic diarrhea is defined as a decrease in fecal consistency lasting for four or more weeks. Prevalence of this complication in the general population is 5%. Mast cells that play an important role in the regulation of gastrointestinal visceral sensitivity and vascular permeability may be involved in functional chronic diarrhea. In this study we tried to evaluate mast cells density in colonic mucosa of patients with chronic diarrhea. Patients and Methods: 50 patients with chronic diarrhea and 50 persons as control group were investigated. All specimens were immunohistochemically stained for mast cell tryptase (MCT) with monoclonal mouse anti-human MCT as well as toluidine blue. Mean number of mucosal mast cells were counted in 10 high power microscopic fields of patients and control groups. Results: In patients group (age range, 15-78 years; 26 females), the number of mast cells per high power field in the immunohistochemistry staining was 21.3 ± 4.8 compared to 14.2 ± 3.4 in the control group (age range, 18-78 years; 24 females) [P < 0.001]. Also number of mast cells in toluidine blue staining was 10.3 ± 3.6 per high power field in cases and 7.1 ± 2.4 in the control group (P < 0.001). Conclusion: Elevated number of colonic mast cells exist in patients with chronic diarrhea. Further research should be considered on application of these findings for new therapeutic opportunities. [ABSTRACT FROM AUTHOR]

Bisphosphonates are theprincipaldrugs prescribed for the preventionof osteoporotic fractures.They arebone specific but poorly absorbed. In oral formulations, almost 99% of the administered dose remains within the intestinal tract and reaches the small and large bowel. Although the nitrogen-containing bisphosphonates can irritate the distal esophageal/gastricmucosa, they improve drug-induced colitis in animal models and exhibit antitumor properties on intestinal cells in vitro. Several recent epidemiological studies provide evidence of a reduced risk of colorectal cancer in osteoporotic patients treated with oral bisphosphonates, notably alendronate. In this review, we will explore the possible mechanisms of action underlying these effects and raise the question of whether these agents might be used in the chemoprophylaxis against colorectal cancer. [ABSTRACT FROM AUTHOR]

Abstract: The tissue distribution of folate in its numerous coenzyme forms may influence the development of disease at different sites. For instance, the susceptibility of human colonic mucosa to localized folate deficiency may predispose to the development of colorectal cancer. We report a sensitive and robust ultra high-performance liquid chromatography (UHPLC) tandem mass spectrometry method for quantifying tissue H4folate, 5-CH3-H4folate, 5-CHO-H4folate, folic acid, and 5,10-CH+-H4folate concentration. Human colonic mucosa (20–100mg) was extracted using lipase and conjugase enzyme digestion. Rapid separation of analytes was achieved on a UHPLC 1.9-μm C18 column over 7min. Accurate quantitation was performed using stable isotopically labeled (13C5) internal standards. The instrument response was linear over physiological concentrations of tissue folate (R 2 >0.99). Limits of detection and quantitation were less than 20 and 30fmol on column, respectively, and within- and between-run imprecision values were 6–16%. In colonic mucosal samples from 73 individuals, the average molar distribution of folate coenzymes was 58% 5-CH3-H4folate, 20% H4folate, 18% formyl-H4folate (sum of 5-CHO-H4folate and 5,10-CH+-H4folate), and 4% folic acid. This assay would be useful in characterizing folate distribution in human and animal tissues as well as the role of deregulated folate homeostasis on disease pathogenesis. [Copyright &y& Elsevier]

Abstract: Aim of the study: Lubricating gut pill (LGP), a traditional Chinese formula, had been conformed to improve the loperamide-induced rat constipation by stimulation of Cl− secretion, but its mechanism has not been fully explored. Thus, the purpose of this study was to identify the action sites of LGP-stimulated Cl− secretion across rat distal colonic mucosa. Materials and methods: Rat distal colonic mucosa was mounted in Ussing chambers and short circuit current (I SC), apical Cl− current and basolateral K+ current were recorded. Intracellular cyclic adenosine monophosphate (cAMP) content and protein kinase A (PKA) activity were determined with ELISA kit and the non-radioactive PepTag test, respectively. Results: LGP at 800μg/ml elicited a sustained increase in Cl− secretory response, which was inhibited by CFTRinh172, a cystic fibrosis transmembrane conductance regulator (CFTR) inhibitor. Permeabilizing apical membrane with nystatin revealed that LGP-stimulated basolateral K+ current was significantly inhibited by KCNQ1 K+ channel inhibitor chromanol 293B. LGP-stimulated I SC was markedly reduced by pretreatment with cis-N-[2-phenylcyclopentyl]-azacyclotridec-1-en-2amine (MDL-12,330A) and N-[2-(p-bromocinnamylamino)ethyl]-5-isoquinolinesulfonamide (H-89), but not with inhibitors of Ca2+-dependent signaling pathway. Treatment of tissue with LGP resulted in an increase in intracellular cAMP level and the activation in protein kinase A. The E-prostanoid4 (EP)4 receptor antagonist L-161,982 completely eliminated LGP-induced response. Conclusions: The results showed that LGP enhances Cl− and fluid secretion via prostanoid receptor signaling and also cAMP and protein kinase A pathway, subsequently triggering the activation of apical Cl− channels mostly CFTR and basolateral cAMP-dependent K+ channel. [Copyright &y& Elsevier]

Purpose: Tacrolimus is a potent immunomodulator that is effective in the treatment of inflammatory bowel disease (IBD). However, potential toxicity and systemic effects with oral intake limit its use. Local tacrolimus treatment is effective in a subgroup of proctitis patients. This study aimed to evaluate whether colonic mucosal immune cells are susceptible to locally applied tacrolimus in vitro. Our in vivo studies aimed at evaluating whether local tacrolimus treatment in mice would bring about local immune suppression and to compare colonic and systemic tacrolimus levels after locally and systemically applied tacrolimus.Results: In vitro tacrolimus inhibited the activation of multiple cell types present in colonic tissue; lamina propria T cells, NKT cells, and both classical- and non- classical antigen presenting cells. However, the cytokine production of epithelial cells was not inhibited by tacrolimus at these concentrations. After rectal administration in mice, tacrolimus blood levels were comparable to those obtained by oral intake. However, rectally treated mice exhibited a 14-fold higher concentration of tacrolimus within their colonic tissue than orally treated mice. Moreover, rectally applied tacrolimus resulted in a local but not a systemic immune suppression in mice.Conclusions: Tacrolimus inhibits activation of several pivotal immune cells of the intestinal mucosa. Murine studies indicate that colonic application of tacrolimus induces local rather than systemic immune suppression. [ABSTRACT FROM AUTHOR]

Abstract: With the aim of investigating whether cholesterol oxidation products could contribute to the pathogenesis of the intestinal epithelial barrier dysfunction that occurs in human inflammatory bowel disease (IBD), differentiated versus undifferentiated CaCo-2 cells, an accepted model for human intestinal epithelial cells, were challenged with a dietary-representative mixture of oxysterols. Only differentiated colonic cells were susceptible to the proapoptotic action of the oxysterol mixture, checked both by enzymatic and by morphological methods, mainly because of a very low AKT phosphorylation pathway compared to the undifferentiated counterparts. Enhanced production of reactive oxygen species by a colonic NADPH oxidase hyperactivation seemed to represent the key event in oxysterol-induced up-regulation of the mitochondrial pathway of programmed death of differentiated CaCo-2 cells. These in vitro findings point to the pro-oxidant and cytotoxic potential of cholesterol oxidation products, of both dietary and endogenous origin, as an important mechanism of induction and/or worsening of the functional impairment of enteric mucosa that characterizes IBD. [Copyright &y& Elsevier]

Abstract: Objective: To investigate the alternations of proteins in the colonic mucosa of chronic slow transit constipation (STC) rats with a 2-DE-based proteomic method and analyze the function of these down-regulated proteins so as to provide theoretical basis for the pathogenesis of intestinal mucosa of chronic STC rats. Methods: STC model was established by feeding rats with 8 mg/(kg·d) diphenoxylate for 120 d. An experimental model of chronic STC rat was used for separation of proteomics from colonic mucosa using two-dimensional electrophoresis (2-DE). Proteins altered in expressional level were identified by Image Master 2DElite, mass spectrometry, and bibliometrics were applied to identify the differential protein expression and their clinical significance and function were analyzed. Results: Obvious differential protein expression was observed in the pathogenesis of STC, including mast cell protease (A1), non-specific dipeptidase (A2) and chondrosome succinate dehydrogenase precursor (A3). The expressions of A1, A2 and A3 were down-regulated in the gel graph of STC rats. Conclusion: The down-regulation of chondrosome succinate dehydrogenase, mast cell protease as well as non-specific dipeptidase in rat colon suggests the functional impairment of the oxidoreduction of mitochondrion is very important in the genesis and development of STC. The immunological reaction of STC rats is weakened, and the function of digesting and absorbing protein may be damaged to some extent. [Copyright &y& Elsevier]

Abstract: The unprocessed gastrin precursor, progastrin (PG), is often overexpressed in colon cancer and other malignancies where it appears to stimulate colonic growth. Overexpression of progastrin also stimulates proliferation of normal colonic mucosa, but the receptors mediating these effects have not been identified. Here we report the development of a non-radioactive assay for assessment of PG binding to normal and transformed cells. Progastrin was labeled using biotinylation, and binding of biotinylated PG to cells was assessed using flow cytometry. Using this approach, we show strong and specific binding of PG to some cell lines (IEC-6, IEC-18, HT-29, COLO320) and minimal binding to others (HeLa, DC2.4, Jurkat). We also found PG binding to several non-gut epithelial lines, such as CHO-K1, COS-6 and HEK293 cells. The specificity of binding was confirmed by competition with cold, unlabeled PG but not with glycine-extended gastrin or amidated gastrin-17. Binding was not influenced by the presence of the classical CCK-2 receptor, but was partially dependent on the charged glycosaminoglycans (GAG). The analysis of primary colonic tissues isolated from wild type C57BL/6 mouse, revealed a small epithelial subpopulation of non-hematopoietic (CD45-negative) cells that strongly interacted with PG. Surprisingly, this population was greatly expanded in gastrin knockout mice. This non-radioactive, FACS-based assay should prove useful for further characterization of cells expressing the progastrin receptor. [Copyright &y& Elsevier]

Abstract: Background and aims: Increased epithelial cell proliferation may be detected in diverticular disease, but antibiotics have failed in reducing it. We assess therefore the effect of mesalazine on epithelial cell proliferation in diverticular disease. Methods: A prospective study was conducted on 20 consecutive patients with a new endoscopic diagnosis of symptomatic uncomplicated diverticular disease. The patients were treated with mesalazine 1.6mg/day for 1 year. The Ki-67 antigen index of the whole crypt and in the upper third was separately evaluated before and after starting the treatment. Results: Cell proliferation index was higher in diverticular disease patients than healthy controls both in the whole crypt (median 6.7%, range 2–9% vs. median 1.6%, range 1–3%, p =0.001) and in the upper third of the crypt (median 6.8%, range 2–8% vs. median 1.8%, range 1–3%, p =0.001). Cell proliferation decreased throughout the follow-up. In the whole crypt it was 6.7% at entry and 3.8% at the end of treatment (p <0.005), whereas it was 6.8% at entry and 2.9% at the end of treatment in the upper third of the crypt (p <0.005). Conclusions: We found mesalazine effective in reducing the colonic cell proliferation in long-term treatment for colonic diverticular disease. [Copyright &y& Elsevier]

Summary: Several systemic disorders and gastrointestinal diseases may be associated with increased colonic mucosal eosinophils, which may vary in number throughout the normal colon. Some investigators have proposed that colonic eosinophilia reflects allergen exposure, although this hypothesis has never been validated, and values quantifying the number of mucosal eosinophils that can be regarded as a normal finding are lacking. The aims of this study were to determine the number of intramucosal eosinophils normally present throughout the colon and evaluate the relationship between colonic eosinophilia and seasonal allergen exposure. Eosinophils in the crypt epithelium and lamina propria were evaluated in 198 mucosal biopsy specimens obtained from the ascending (n = 98) and descending (n = 100) colon of patients with normal colonoscopic examinations. The cases were stratified into 12 groups, reflecting the months during which the samples were obtained, and the mean number of mucosal eosinophils was determined for each group. Daily air pollen counts were recorded, and the mean determined for each month. Fifty-five percent of mucosal biopsy specimens from the ascending colon contained eosinophils in the crypt epithelium, compared with only 5% of biopsy specimens from the descending colon (P < .001). Lamina propria eosinophils were, on average, 3 times more numerous in the ascending compared with the descending colon (P < .001). Mucosal eosinophils were slightly more numerous in samples obtained in April and May, corresponding to periods of highest pollen counts, but this relationship was not significant (P > .05). We conclude that intramucosal eosinophils are commonly present in the proximal colon but show only mild fluctuations with ambient allergen exposure. [Copyright &y& Elsevier]

Background and purpose:The protoberberine alkaloid berberine has been reported to inhibit colonic Cl− secretion. However, it is not known if other protoberberine alkaloids share these effects. We have therefore selected another protoberberine alkaloid, palmatine, to assess its effects on active ion transport across rat colonic epithelium.Experimental approach:Rat colonic mucosa was mounted in Ussing chambers and short circuit current (I SC), apical Cl− current and basolateral K+ current were recorded. Intracellular cAMP content was determined by an enzyme immunoassay. Intracellular Ca2+ concentration was measured with Fura-2 AM.Key results:Palmatine inhibited carbachol-induced Ca2+-activated Cl− secretion and the carbachol-induced increase of intracellular Ca2+ concentration. Palmatine also inhibited cAMP-activated Cl− secretion induced by prostaglandin E2 (PGE2) or forskolin. Palmatine prevented the elevation of intracellular cAMP by forskolin. Determination of apical Cl− currents showed that palmatine suppressed the forskolin-stimulated, apical cAMP-activated Cl− current but not the carbachol-stimulated apical Ca2+-activated Cl− current. Following permeabilization of apical membranes with nystatin, we found that palmatine inhibited a carbachol-stimulated basolateral K+ current that was sensitive to charybdotoxin and resistant to chromanol 293B. However, the forskolin-stimulated basolateral K+ current inhibited by palmatine was specifically blocked by chromanol 293B and not by charybdotoxin.Conclusions and implications:Palmatine attenuated Ca2+-activated Cl− secretion through inhibiting basolateral charybdotoxin-sensitive, SK4 K+ channels, whereas it inhibited cAMP-activated Cl− secretion by inhibiting apical CFTR Cl− channels and basolateral chromanol 293B-sensitive, KvLQT1 K+ channels.British Journal of Pharmacology (2008) 153, 1203–1213; doi:10.1038/sj.bjp.0707684; published online 21 January 2008 [ABSTRACT FROM AUTHOR]

Objective. Various markers characterize the complex inflammatory processes seen in chronic inflammatory bowel disease (IBD) including calprotectin, a complex of two S100 proteins, which has been evaluated and validated as a faecal marker of inflammation. However, the systemic and mucosal expression patterns of calprotectin and related S100 proteins are not well characterized in this disease. The objective of this study was to assess serum and mucosal levels of calprotectin, S100A12 and soluble receptor for advanced glycation end products (sRAGE), a putative S100 ligand, in a paediatric population with IBD. Material and methods. Children were enrolled at diagnosis of IBD, along with groups of children without IBD. Standard inflammatory markers and disease activity scores were collated. Calprotectin, S100A12 and sRAGE levels in serum and biopsy culture supernatants were measured by ELISA and tissue distribution of S100 proteins was investigated by immunohistochemistry. Results. Serum and mucosal calprotectin and S100A12 levels were increased in children with IBD as compared with non-IBD controls. Serum calprotectin levels correlated with S100A12 levels and with disease activity scores in children with IBD. sRAGE levels were not increased in IBD. S100A8, S100A9 and S100A12 were abundantly expressed throughout the lamina propria and epithelium in inflamed mucosa. In contrast, these proteins were present in the lamina propria, but not the epithelium, in non-inflamed mucosa. Conclusions. Serum calprotectin and S100A12 are increased in children with IBD and indicate disease activity. Elevated levels of these proteins are present in the colonic mucosa and may contribute to the pathogenesis of IBD. Furthermore, an imbalance between sRAGE and S100A12 may contribute to inflammatory changes present in IBD. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: We evaluated the applications and outcomes of substitution urethroplasty, using a variety of techniques, in 65 patients with complex, long-segment urethral strictures. Methods: From January 1995 to December 2005, 65 patients with complex urethral strictures >8cm in length underwent substitution urethroplasty. Of the 65 patients, 43 underwent one-stage urethral reconstruction using mucosal grafts (28 colonic mucosal graft, 12 buccal mucosal graft, and 3 bladder mucosal graft), 17 patients underwent one-stage urethroplasty using pedicle flaps, and 5 patients underwent staged Johanson''s urethroplasty. Results: The mean follow-up time was 4.8 yr (range; 0.8–10 yr), with an overall success rate of 76.92% (50 of 65 cases). Complications developed in 15 patients (23.08%) and included recurrent stricture in 7 (10.77%), urethrocutaneous fistula in 3 (4.62%), coloabdominal fistula in 1 (1.54%), penile chordee in 2 (3.08%), and urethral pseudodiverticulum in 2 (3.08%). Recurrent strictures and urethral pseudodiverticulum were treated successfully with a subsequent procedure, including repeat urethroplasty in six cases and urethrotomy or dilation in three. Coloabdominal fistula was corrected only by dressing change; five patients await further reconstruction. Conclusions: Penile skin, colonic mucosal, and buccal mucosal grafts are excellent materials for substitution urethroplasty. Colonic mucosal graft urethroplasty is a feasible procedure for complicated urethral strictures involving the entire or multiple portions of the urethra and the technique may also be considered for urethral reconstruction in patients in whom other conventional procedures failed. [Copyright &y& Elsevier]