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Intestine
Kinds of Intestine Terms modified by Intestine Selected AbstractsSMALL AND LARGE INTESTINEJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 2006Article first published online: 15 NOV 200 [source] ORIGINAL ARTICLE: Conversion of viable but nonculturable Vibrio cholerae to the culturable state by co-culture with eukaryotic cellsMICROBIOLOGY AND IMMUNOLOGY, Issue 9 2010Mitsutoshi Senoh ABSTRACT VBNC Vibrio cholerae O139 VC-280 obtained by incubation in 1% solution of artificial sea water IO at 4°C for 74 days converted to the culturable state when co-cultured with CHO cells. Other eukaryotic cell lines, including HT-29, Caco-2, T84, HeLa, and Intestine 407, also supported conversion of VBNC cells to the culturable state. Conversion of VBNC V. cholerae O1 N16961 and V. cholerae O139 VC-280/pG13 to the culturable state, under the same conditions, was also confirmed. When VBNC V. cholerae O139 VC-280 was incubated in 1% IO at 4°C for up to 91 days, the number of cells converted by co-culture with CHO cells declined with each additional day of incubation and after 91 days conversion was not observed. [source] Protective Effects of Ischemic Preconditioning on the Intestinal Mucosal Microcirculation Following Ischemia,Reperfusion of the IntestineMICROCIRCULATION, Issue 8 2005ISMAIL H. MALLICK ABSTRACT Objective: The small bowel villi are extremely sensitive to ischemia,reperfusion (IR) injury and a range of microcirculatory disturbances contribute to structural and functional changes. The aim of this study was to determine the protective effects of ischemic preconditioning (IPC) of the intestine on the mucosal villous microcirculation during IR injury of the intestine and whether heme oxygenase (HO) is involved in the protection. Methods: Rats were allocated into 4 groups: (1) sham, (2) IR consisting of 30 min of ischemia followed by 2 h of reperfusion, (3) IPC, as in IR group, but preceded by 10 min of ischemia and 10 min of reperfusion, and (4) with administration of zinc protoporphyrin, an HO inhibitor before IPC and IR. The mucosa of an exteriorized segment of ileum was visualized. Mucosal perfusion index (MPI), red blood cell (RBC) velocity and leukocyte,endothelial interactions during reperfusion were assessed continuously using in vivo fluorescence microscopy. HO activity in the ileum was assessed at the end of the reperfusion period. Results: IPC improved the MPI by 26% and the RBC velocity by 29% on comparison to IR. IR led to a 52% increase in leukocyte,endothelial interactions on comparison to IPC. The administration of zinc protoporphyrin reversed the beneficial effects of IPC. There was a two fold increase of HO activity in IPC compared to IR, whereas zinc protoporphyrin significantly reduced the HO activity. Conclusions: IPC conferred a protective effect on the villous microcirculation possibly via HO and might prove to be an effective strategy for the amelioration of IR injury. [source] Isolation of a Thermotolerant Paravahlkampfia sp. from Lizard Intestine: Biology and Molecular IdentificationTHE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 5 2003FREDERICK L. SCHUSTER ABSTRACT. An amoeba was isolated from the intestines of several moribund pink-tongued skinks (lizards), Hemisphaeriodon ger-rardi Unusual features of this isolate were its ability to grow at temperatures of , 37 °C, and its inability to use Escherichia coli as a food source or to grow axenically on a variety of enriched culture media suitable for other soil amoeba isolates. Growth was abundant, however, on tissue culture cells, with amoebae clearing cell monolayers in ,48 h at 37 °C. Trophozoites had a vahlkampfiid-like morphology, moving by means of an anterior eruptive pseudopod. Cysts, round to slightly ovoid and lacking exit pores, were formed in culture. Tests for enflagellation of trophic amoebae were negative. Indirect immunofluorescence staining was negative for Naegleria fowleri and Willaertia sp. The isolate was sensitive to azithromycin, but not to amphotericin B, pentamidine isethionate, fluconazole, 5-fluorocytosine, and sulfadiazine. Phylogenetic analysis based on the PCR-amplified small subunit ribosomal DNA, identified the organism as Paravahlkampfia ustiana, an amoeba not previously isolated from either poikilothermic or homeothermic hosts. No evidence of pathology was seen in stained sections of lizard intestine, suggesting that the ameba was part of the normal fauna of the lizard gut. Its diet in the lizard intestine is unknown and the organism may have unusual growth requirements. Thus, P. ustiana joins other soil amoebae that have been isolated from mammals, amphibia, fish, and reptiles, which have the potential of becoming opportunistic pathogens. [source] Modulation of Brain Dead Induced Inflammation by Vagus Nerve StimulationAMERICAN JOURNAL OF TRANSPLANTATION, Issue 3 2010S. Hoeger Because the vagus nerve is implicated in control of inflammation, we investigated if brain death (BD) causes impairment of the parasympathetic nervous system, thereby contributing to inflammation. BD was induced in rats. Anaesthetised ventilated rats (NBD) served as control. Heart rate variability (HRV) was assessed by ECG. The vagus nerve was electrically stimulated (BD + STIM) during BD. Intestine, kidney, heart and liver were recovered after 6 hours. Affymetrix chip-analysis was performed on intestinal RNA. Quantitative PCR was performed on all organs. Serum was collected to assess TNF, concentrations. Renal transplantations were performed to address the influence of vagus nerve stimulation on graft outcome. HRV was significantly lower in BD animals. Vagus nerve stimulation inhibited the increase in serum TNF, concentrations and resulted in down-regulation of a multiplicity of pro-inflammatory genes in intestinal tissue. In renal tissue vagal stimulation significantly decreased the expression of E-selectin, IL1, and ITGA6. Renal function was significantly better in recipients that received a graft from a BD + STIM donor. Our study demonstrates impairment of the parasympathetic nervous system during BD and inhibition of serum TNF, through vagal stimulation. Vagus nerve stimulation variably affected gene expression in donor organs and improved renal function in recipients. [source] Rejection Reversibly Alters Enteroendocrine Cell Renewal in the Transplanted Small IntestineAMERICAN JOURNAL OF TRANSPLANTATION, Issue 7 2009T. M. Fishbein Acute small intestinal allograft rejection presents clinically as an abrupt increase in ileal fluid output in the absence of extensive inflammation. We questioned whether acute intestinal rejection might be accompanied by a disturbance of normal intestinal stem cell differentiation. We examined the intestinal epithelial secretory cell lineage among patients experiencing early rejection before and during rejection as well as following corrective therapy. Lineage-specific progenitors were identified by their expression of stage-specific transcription factors. Progenitors of the enteroendocrine cell (EEC) expressing neurogenin-3 (NEUROG3) were found to be disproportionately reduced in numbers, along with their more mature EEC derivatives expressing neuro D; the enteric hormone PYY was the most profoundly depleted of all the EEC products evaluated. No change in the numbers of goblet or Paneth cells was observed. Steroid treatment resulted in resolution of clinical symptoms, restoration of normal patterns of EEC differentiation and recovery of normal levels of enteric hormones. Acute intestinal rejection is associated with a loss of certain subtypes of EEC, most profoundly, those expressing PYY. Deficiency of the mature EECs appears to occur as a consequence of a mechanism that depletes NEUROG3 EEC progenitors. Our study highlights the dynamics of the EEC lineage during acute intestinal rejection. [source] Transplantation of the Intestine: Is it Truly Different?AMERICAN JOURNAL OF TRANSPLANTATION, Issue 1 2003Kenneth A. Newell No abstract is available for this article. [source] Gross Anatomy of the Intestine in the Giraffe (Giraffa camelopardalis)ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 6 2009W. Pérez Summary We describe the macroscopic anatomy of the intestine of the giraffe (Giraffa camelopardalis). The small intestine was divided into duodenum, jejunum and ileum as usual. The caecum was attached to the ileum by a long ileocaecal fold, and to the proximal ansa of the ascending colon by a caecocolic fold. The ascending colon was the most developed portion of the gross intestine and had the most complex arrangement with three ansae: the proximal ansa, the spiral ansa and the distal ansa. The proximal ansa completely encircled the caecum, describing a 360° gyrus, and represented the widest portion of the intestine. The spiral ansa was formed by three and a half centripetal gyri, a central flexure and three centrifugal gyri. The last centrifugal gyrus left the spiral and described nine flexures of different form and direction over the left side of the mesentery. The two portions that formed each of these flexures ran parallel to each other. The last part of this gyrus ran parallel to the jejunum. When compared with domestic cattle, giraffe had a comparatively short small intestine and a comparatively long large intestine, with a resulting small ratio of small:large intestine. Reasons are presented why this should be considered a peculiarity of cattle-like ruminants rather than a different representative of a browser,grazer dichotomy in general. [source] Features of chronic allograft rejection on rat small intestine transplantationPEDIATRIC TRANSPLANTATION, Issue 2 2007Hao Ma Abstract:, The aim of this study was to develop a model of chronic rejection of the entire small intestine transplantation and to analyze the features of chronic rejection. Allogenic small bowel transplantation was performed in a rat combination of Lewis to F344. Intestines were procured at the 60th and the 90th day after operation. We compared the semiquantitative score of histological parameters. The immunological components involved in the chronic rejection process were evaluated by immunohistochemical staining and the cytokine levels in grafts. The significant characteristics of the allograft on histology were changes of villous architecture, interstitial fibrosis, leukocyte infiltration, and obliterative arteriopathy. Allografts on the 60th day post-transplantation had more score in inflammatory events, while the grafts on the 90th day after operation had more values in ischemia/fibrotic events. The number of infiltrating CD4, CD8 and macrophage cells in allografts progressively decreased over time. The level of intrgraft cytokines such as IL-6, TNF- , and IL-10 in the 90th day after transplantation also decreased compared with that in the 60th day. These data suggested that in the early stage (POD 60), there were more active and intense inflammatory events; later (POD 90) allografts manifested less inflammation and more arterial obliteration and fibrosis. [source] Utilization of waste material resulting from trout processing in gilthead bream (Sparus aurata L.) dietsAQUACULTURE RESEARCH, Issue 2001Y P Kotzamanis Abstract Fish processing creates a large amount of waste of high nutrient content which, if not properly processed for use in human or animal nutrition, is likely to be deposited in the environment creating pollution problems. Waste parts from rainbow trout processing for smoking, consisting of heads, bones, tails and intestines, were used as feed ingredients for gilthead bream diets. Heads, bones and tails had similar compositions, their weighed mean indicating about 700 g kg,1 moisture, 150 g kg,1 protein and 110 g kg,1 fat. Intestines contained higher lipid (350 g kg,1) and lower moisture (560 g kg,1) and protein content (80 g kg,1). Seasonal changes in composition indicated significant differences. Three experimental diets were formulated having the same proximate composition on a dry weight basis. The control diet (A) contained fish meal as the main protein source and fish oil as the oil supplement. In diet B part of the protein and most of lipid was provided by trout waste and in diet C most of the lipid was provided by trout intestines. Gilthead bream fingerlings of 4 g initial weight were fed to apparent satiation for 72 days, at a temperature of 20 °C, to an average final weight of 19 g. All diets were fed in a dry form. The experiment was performed in duplicate. Growth and feed utilization data were high and similar among groups. The body composition of the resulting fish did not show any difference among dietary treatments. Differences in liver lipid and fatty acid content were found between all dietary treatments. The growth and body composition data from this preliminary experiment indicated that trout waste could be used successfully as a dietary ingredient of sea bream diets. [source] Encroachment of Echinococcus granulosus into urban areas in eastern Queensland, AustraliaAUSTRALIAN VETERINARY JOURNAL, Issue 8 2008DJ Jenkins Objective To investigate the prevalence of Echinococcus granulosus in wild dogs (dingos and dingo,domestic dog hybrids) living in and around human habitation on Fraser Island and in townships of the Maroochy Shire, on Queensland's Sunshine Coast, Australia. Design Wild dogs were humanely killed on Fraser Island and in the Maroochy Shire because they were deemed a potential danger to the public. Their intestines were collected and the contents examined for intestinal parasites. Procedure Intestines were removed as soon after death as possible, packed in plastic bags and kept frozen until examination. The intestinal contents were washed, sieved and examined microscopically for the presence of helminths, which were identified and counted. Results Intestines from 108 wild dogs, 7 foxes and 18 Fraser Island dingoes were examined. Echinococcus granulosus was only present in the wild dogs from Maroochy Shire (46.3%) with worm burdens of between 30 and 104,000. Other helminths included Spirometra erinacei, Dipylidium caninum, Taenia spp., Ancylostoma caninum and Toxocara canis. Two specimens of a trematode (Haplorchinae sp.) usually found infecting fish and seabirds were recovered from a Fraser Island dingo. Conclusion Dingoes on Fraser Island are not infected with E. granulosus and do not pose a hydatid disease public health risk to residents or visitors. However, wild dogs examined from the Maroochy Shire do present a potential hydatid disease public health risk. [source] Isolated levocardia: Prenatal diagnosis and managementCONGENITAL ANOMALIES, Issue 2 2009Satoko Katsuya ABSTRACT Isolated levocardia (IL) is a rare condition of situs anomaly in which there is a normal left-sided heart (levocardia) with dextro position of the abdominal viscera. IL has been reported in children and adults with complex cardiac defects, whereas there are only few published reports regarding the prenatal diagnosis of IL. We report two prenatal cases of IL diagnosed by ultrasonography and magnetic resonance imaging (MRI). In both cases, fetal cardiac function remained within the normal range throughout pregnancy, and no treatment for the heart was required after birth. For the dextro position of abdominal viscera, one case was followed without any surgical procedure, but the other case required prophylactic operation due to malrotation of the small intestine. Although the prognosis of IL largely depends on the severity of associated cardiac anomaly, future bowel obstruction caused by intestinal malrotation may also be life-threatening. In this respect, prenatal diagnosis of IL is important, even when there is no associated cardiac structural anomaly. If IL is suspected in routine fetal ultrasonography, MRI may be recommended to obtain more detailed information on the anatomy of abdominal viscerae, and careful observation for bowel problems is required, especially after oral nutrition is started. [source] The lateral intercellular space as osmotic coupling compartment in isotonic transportACTA PHYSIOLOGICA, Issue 1 2009E. H. Larsen Abstract Solute-coupled water transport and isotonic transport are basic functions of low- and high-resistance epithelia. These functions are studied with the epithelium bathed on the two sides with physiological saline of similar composition. Hence, at transepithelial equilibrium water enters the epithelial cells from both sides, and with the reflection coefficient of tight junction being larger than that of the interspace basement membrane, all of the water leaves the epithelium through the interspace basement membrane. The common design of transporting epithelia leads to the theory that an osmotic coupling of water absorption to ion flow is energized by lateral Na+/K+ pumps. We show that the theory accounts quantitatively for steady- and time dependent states of solute-coupled fluid uptake by toad skin epithelium. Our experimental results exclude definitively three alternative theories of epithelial solute,water coupling: stoichiometric coupling at the molecular level by transport proteins like SGLT1, electro-osmosis and a ,junctional fluid transfer mechanism'. Convection-diffusion out of the lateral space constitutes the fundamental problem of isotonic transport by making the emerging fluid hypertonic relative to the fluid in the lateral intercellular space. In the Na+ recirculation theory the ,surplus of solutes' is returned to the lateral space via the cells energized by the lateral Na+/K+ pumps. We show that this theory accounts quantitatively for isotonic and hypotonic transport at transepithelial osmotic equilibrium as observed in toad skin epithelium in vitro. Our conclusions are further developed for discussing their application to solute,solvent coupling in other vertebrate epithelia such as small intestine, proximal tubule of glomerular kidney and gallbladder. Evidence is discussed that the Na+ recirculation theory is not irreconcilable with the wide range of metabolic cost of Na+ transport observed in fluid-transporting epithelia. [source] Mathematical and experimental insights into the development of the enteric nervous system and Hirschsprung's DiseaseDEVELOPMENT GROWTH & DIFFERENTIATION, Issue 4 2007Kerry A. Landman The vertebrate enteric nervous system is formed by a rostro-caudally directed invasion of the embryonic gastrointestinal mesenchyme by neural crest cells. Failure to complete this invasion results in the distal intestine lacking intrinsic neurons. This potentially fatal condition is called Hirschsprung's Disease. A mathematical model of cell invasion incorporating cell motility and proliferation of neural crest cells to a carrying capacity predicted invasion outcomes to imagined manipulations, and these manipulations were tested experimentally. Mathematical and experimental results agreed. The results show that the directional invasion is chiefly driven by neural crest cell proliferation. Moreover, this proliferation occurs in a small region at the wavefront of the invading population. These results provide an understanding of why many genes implicated in Hirschsprung's Disease influence neural crest population size. In addition, during in vivo development the underlying gut tissues are growing simultaneously as the neural crest cell invasion proceeds. The interactions between proliferation, motility and gut growth dictate whether or not complete colonization is successful. Mathematical modeling provides insights into the conditions required for complete colonization or a Hirschsprung's-like deficiency. Experimental evidence supports the hypotheses suggested by the modeling. [source] One of the duplicated matrix metalloproteinase-9 genes is expressed in regressing tail during anuran metamorphosisDEVELOPMENT GROWTH & DIFFERENTIATION, Issue 4 2006Kenta Fujimoto The drastic morphological changes of the tadpole are induced during the climax of anuran metamorphosis, when the concentration of endogenous thyroid hormone is maximal. The tadpole tail, which is twice as long as the body, shortens rapidly and disappears completely in several days. We isolated a cDNA clone, designated as Xl MMP-9TH, similar to the previously reported Xenopus laevis MMP-9 gene, and showed that their Xenopus tropicalis counterparts are located tandemly about 9 kb apart from each other in the genome. The Xenopus MMP-9TH gene was expressed in the regressing tail and gills and the remodeling intestine and central nervous system, and induced in thyroid hormone-treated tail-derived myoblastic cultured cells, while MMP-9 mRNA was detected in embryos. Three thyroid hormone response elements in the distal promoter and the first intron were involved in the upregulation of the Xl MMP-9TH gene by thyroid hormone in transient expression assays, and their relative positions are conserved between X. laevis and X. tropicalis promoters. These data strongly suggest that the MMP-9 gene was duplicated, and differentiated into two genes, one of which was specialized in a common ancestor of X. laevis and X. tropicalis to be expressed in degenerating and remodeling organs as a response to thyroid hormone during metamorphosis. [source] Digestive tract ontogeny of Dicentrarchus labrax: Implication in osmoregulationDEVELOPMENT GROWTH & DIFFERENTIATION, Issue 3 2006Ivone Giffard-Mena The ontogeny of the digestive tract (DT) and of Na+/K+ -ATPase localization was investigated during the early postembryonic development (from yolk sac larva to juvenile) of the euryhaline teleost Dicentrarchus labrax reared at two salinities: seawater and diluted seawater. Histology, electron microscopy and immunocytochemistry were used to determine the presence and differentiation of ion transporting cells. At hatching, the DT is an undifferentiated straight tube over the yolk sac. At the mouth opening (day 5), it comprises six segments: buccopharynx, esophagus, stomach, anterior intestine, posterior intestine and rectum, well differentiated at the juvenile stage (day 72). The enterocytes displayed ultrastructural features similar to those of mitochondria-rich cells known to be involved in active ion transport. At hatching, ion transporting cells lining the intestine and the rectum exhibited a Na+/K+ -ATPase activity which increased mainly after the larva/juvenile (20 mm) metamorphic transition. The immunofluorescence intensity was dependent upon the stage of development of the gut as well as on the histological configuration of the analyzed segment. The appearance and distribution of enteric ionocytes and the implication of the DT in osmoregulation are discussed. [source] Correlation between Musashi-1 and c-hairy-1 expression and cell proliferation activity in the developing intestine and stomach of both chicken and mouseDEVELOPMENT GROWTH & DIFFERENTIATION, Issue 8 2005Rieko Asai Musashi-1 (Msi-1) is an RNA-binding protein that plays key roles in the maintenance of neural stem cell states and in their differentiation into neural cells. Msi-1 has also been proposed as a candidate marker gene of mammalian intestinal stem cells and their immediate lineages. In this study, we examined Msi-1 expression in the small intestine and the stomach of both chicken and mouse during embryonic, fetal and postnatal development. In addition, we analyzed the expression of c-hairy-1, a chicken homologue of mouse Hes1, and assessed the proliferative activity of the cells expressing both of these factors. Significantly, during the development of these digestive organs in both species Msi-1 expression showed dynamic changes, suggesting that it is important for digestive organ development, particularly for epithelial differentiation. Based on our observations of the expression patterns of Msi-1 and c-hairy-1 in the adult small intestine, we speculate that Msi-1 is also a stem cell marker of the chicken small intestinal epithelium. [source] Transcriptional dynamics of endodermal organ formationDEVELOPMENTAL DYNAMICS, Issue 1 2009Richard I. Sherwood Abstract Although endodermal organs including the liver, pancreas, and intestine are of significant therapeutic interest, the mechanism by which the endoderm is divided into organ domains during embryogenesis is not well understood. To better understand this process, global gene expression profiling was performed on early endodermal organ domains. This global analysis was followed up by dynamic immunofluorescence analysis of key transcription factors, uncovering novel expression patterns as well as cell surface proteins that allow prospective isolation of specific endodermal organ domains. Additionally, a repressive interaction between Cdx2 and Sox2 was found to occur at the prospective stomach,intestine border, with the hepatic and pancreatic domains forming at this boundary, and Hlxb9 was revealed to have graded expression along the dorsal,ventral axis. These results contribute to understanding the mechanism of endodermal organogenesis and should assist efforts to replicate this process using pluripotent stem cells. Developmental Dynamics 238:29,42, 2009. © 2008 Wiley-Liss, Inc. [source] Shh/BMP-4 signaling pathway is essential for intestinal epithelial development during Xenopus larval-to-adult remodelingDEVELOPMENTAL DYNAMICS, Issue 12 2006Atsuko Ishizuya-Oka Abstract During amphibian larval-to-adult intestinal remodeling, progenitor cells of the adult epithelium actively proliferate and differentiate under the control of thyroid hormone (TH) to form the intestinal absorptive epithelium, which is analogous to the mammalian counterpart. We previously found that TH,up-regulated expression of bone morphogenetic protein-4 (BMP-4) spatiotemporally correlates with adult epithelial development in the Xenopus laevis intestine. Here, we aimed to clarify the role of BMP-4 in intestinal remodeling. Our reverse transcriptase-polymerase chain reaction and in situ hybridization analyses indicated that mRNA of BMPR-IA, a type I receptor of BMP-4, is expressed in both the developing connective tissue and progenitor cells of the adult epithelium. More importantly, using organ culture and immunohistochemical procedures, we have shown that BMP-4 not only represses cell proliferation of the connective tissue but promotes differentiation of the intestinal absorptive epithelium. In addition, we found that the connective tissue-specific expression of BMP-4 mRNA is up-regulated by sonic hedgehog (Shh), whose epithelium-specific expression is directly induced by TH. These results strongly suggest that the Shh/BMP-4 signaling pathway plays key roles in the amphibian intestinal remodeling through epithelial,connective tissue interactions. Developmental Dynamics 235:3240,3249, 2006. © 2006 Wiley-Liss, Inc. [source] Hoxb3 vagal neural crest-specific enhancer element for controlling enteric nervous system developmentDEVELOPMENTAL DYNAMICS, Issue 2 2005Kwok Keung Chan Abstract The neural and glial cells of the intrinsic ganglia of the enteric nervous system (ENS) are derived from the hindbrain neural crest at the vagal level. The Hoxb3 gene is expressed in the vagal neural crest and in the enteric ganglia of the developing gut during embryogenesis. We have identified a cis -acting enhancer element b3IIIa in the Hoxb3 gene locus. In this study, by transgenic mice analysis, we examined the tissue specificity of the b3IIIa enhancer element using the lacZ reporter gene, with emphasis on the vagal neural crest cells and their derivatives in the developing gut. We found that the b3IIIa-lacZ transgene marks only the vagal region and not the trunk or sacral region. Using cellular markers, we showed that the b3IIIa-lacZ transgene was expressed in a subset of enteric neuroblasts during early development of the gut, and the expression was maintained in differentiated neurons of the myenteric plexus at later stages. The specificity of the b3IIIa enhancer in directing gene expression in the developing ENS was further supported by genetic analysis using the Dom mutant, a spontaneous mouse model of Hirschsprung's disease characterized by the absence of enteric ganglia in the distal gut. The colonization of lacZ -expressing cells in the large intestine was incomplete in all the Dom/b3IIIa-lacZ hybrid mutants we examined. To our knowledge, this is the only vagal neural crest-specific genetic regulatory element identified to date. This element could be used for a variety of genetic manipulations and in establishing transgenic mouse models for studying the development of the ENS. Developmental Dynamics 233:473,483, 2005. © 2005 Wiley-Liss, Inc. [source] Villin: A marker for development of the epithelial pyloric borderDEVELOPMENTAL DYNAMICS, Issue 1 2002Evan M. Braunstein Abstract In the adult gastrointestinal tract, the morphologic borders between esophagus and stomach and between stomach and small intestine are literally one cell thick. The patterning mechanisms that underlie the development of these sharp regional divisions from a once continuous endodermal tube are still obscure. In the embryonic endoderm of the developing gut, region-specific expression of certain genes (e.g., intestine-specific expression of the actin bundling protein villin) can be detected as early as 9.0 days post coitum, although the morphologic differentiation of the gut epithelium proper does not begin until 4 to 5 days later. By using a mouse model in which a ,-galactosidase marker has been inserted into the endogenous villin locus, we examined the development of the stomach/intestinal (pyloric) border during gut organogenesis. The data indicate that the border is not sharp from the outset. Rather, the initial border region is characterized by a decreasing gradient of villin/,-galactosidase expression that extends into the distal stomach. A sharp epithelial border of villin/,-galactosidase expression appears abruptly at day 16 and is further refined over the next 3 weeks to form the distinct one-cell-thick border characteristic of the adult. These results indicate that an important previously unrecognized patterning event occurs in the gut epithelium at 16 days; this event may define an epithelial compartment boundary between the stomach and the intestine. The villin/,-galactosidase mouse model characterized here provides an excellent substrate with which to further dissect the mechanisms involved in this patterning process. © 2002 Wiley-Liss, Inc. [source] Orlistat 120 mg improves glycaemic control in type 2 diabetic patients with or without concurrent weight lossDIABETES OBESITY & METABOLISM, Issue 4 2009S. Jacob Background:, Both obesity and type 2 diabetes are associated with increased morbidity and mortality. Published data suggest that orlistat 120 mg, a lipase inhibitor used to treat obesity, may improve glycaemic parameters through weight loss,independent effects. Aim:, To investigate the effect of orlistat 120 mg on weight loss, and assess whether changes in glycaemic parameters [fasting plasma glucose (FPG) and haemoglobin A1c (HbA1c)] are independent of weight loss. Methods:, This retrospective analysis of pooled data from seven multicentre, double-blind, placebo-controlled studies involved overweight or obese patients with type 2 diabetes (aged 18,70 years). Patients were required to have a body mass index of 27,43 kg/m2, HbA1c of 6.5 to <13%, and stable weight for ,3 months. Subjects received orlistat 120 mg tid or placebo for 6 or 12 months. Results:, A total of 2550 overweight or obese patients with type 2 diabetes were enrolled and randomized to treatment with orlistat 120 mg tid (n = 1279) or placebo (n = 1271). For the whole population, patients treated with orlistat 120 mg had significantly greater mean decreases in FPG compared with placebo-treated patients (,1.39 mmol/l vs. ,0.47 mmol/l; p < 0.0001). In addition, orlistat 120 mg provided significantly larger mean decreases in HbA1c compared with placebo (,0.74% vs. ,0.31%; p < 0.0001). For patients with minimal weight loss (,1% of baseline body weight), orlistat 120 mg still provided a significantly greater decrease in the least squares mean value for both FPG (,0.83 mmol/l vs. ±0.02 mmol/l; p = 0.0052) and HbA1c,0.29% vs. ±0.14%; p = 0.0008). This suggested that the improvement of glycaemic control with orlistat 120 mg was independent of weight loss. Using linear regression analysis, improvement in glycaemic control (FPG and HbA1c) with orlistat 120 mg was less strongly correlated with weight loss than for placebo. Conclusion:, Orlistat 120 mg appears to improve glycaemic control more than would be predicted by weight loss alone in overweight or obese patients with type 2 diabetes. Postulated mechanisms underlying this effect include an improvement of insulin sensitivity, a slower and incomplete digestion of dietary fat, reduction of postprandial plasma non-esterified fatty acids, decreased visceral adipose tissue, and stimulation of glucagon-like peptide-1 secretion in the lower small intestine. [source] Novel pathways for glycaemic control in type 2 diabetes: focus on bile acid modulationDIABETES OBESITY & METABOLISM, Issue 11 2008Eliot A. Brinton Type 2 diabetes is a common disorder with high risk of macrovascular and microvascular complications. These complications are largely driven by hyperglycaemia, dyslipidaemia and hypertension, for which aggressive treatment is thus warranted. Achieving and maintaining control of all three risk factors is especially difficult, however, and new therapeutic approaches could be useful. Bile acids have a well-established and important role in cholesterol homeostasis. Normally, their levels are maintained primarily by ileal reabsorption and enterohepatic recycling. Bile acid sequestrants bind bile acids in the intestine, reduce this recycling and deplete the bile acid pool, thereby stimulating use of hepatic cholesterol for bile acid synthesis, which leads to accelerated removal of LDL from the plasma and a decrease in LDL-cholesterol levels. Interestingly, recent evidence suggests that bile acid sequestrants can lower glucose levels to a clinically meaningful degree. This review presents this evidence and the possible mechanisms by which these glucose-lowering effects occur and discusses the apparently unique ability of bile acid sequestrants among lipid-lowering agents to significantly improve two cardiovascular risk factors, hyperglycaemia and dyslipidaemia. There is renewed interest in the use of bile acid sequestrants in individuals with type 2 diabetes, most of whom would benefit from additional reductions in both LDL-cholesterol and glycaemia. [source] Antidiabetic and toxicological evaluations of naringenin in normoglycaemic and NIDDM rat models and its implications on extra-pancreatic glucose regulationDIABETES OBESITY & METABOLISM, Issue 11 2008R. R Ortiz-Andrade Aim:, The present investigation was designed to determine the in vivo antidiabetic effect of naringenin (NG) in normoglycaemic and diabetic rat models through blood glucose (GLU) measurements following acute and subchronic time periods. Possible modes of action of NG were investigated and its acute toxicity determined. Methods:, Normoglycaemic and non-insulin-dependent diabetes mellitus (NIDDM) rat models were treated for acute and subchronic (5 days) time periods with 50 mg/kg/day of NG. Blood biochemical profiles were determined after 5 days of the treatment in normoglycaemic and NIDDM rats using commercial kits for GLU, triglycerides (TG), total cholesterol (CHOL) and high-density lipoprotein (HDL). In order to elucidate its antidiabetic mode of action, NG was administered intragastrically and an oral glucose tolerance test performed using GLU and sucrose (2 g/kg) as substrates. The inhibitory effect of a single concentration of NG (10 ,M) on 11,-hydroxysteroid dehydrogenase type 1 (11,-HSD1) activity in vitro was determined. Finally, the preclinical safety and tolerability of NG was determined by toxicological evaluation in mice and rats using Organization for Economic Cooperation and Development (OECD) protocols. Results:, Intragastrically administered NG (50 mg/kg) induced a significant decrease in plasma GLU in normoglycaemic and NIDDM rat models (p < 0.05) following acute and subchronic time periods. After 5 days of administration, NG produced significant diminished blood GLU and TG levels in streptozotocin,nicotinamide,induced diabetic rats. The administration of NG to normal rats significantly increased the levels of TG, CHOL and HDL (p < 0.05). NG (5 and 50 mg/kg) induced a total suppression in the increase of plasma GLU levels after administration of substrates (p < 0.01), but NG did not produce inhibition of ,-glucosidase activity in vitro. However, NG (10 ,M) was shown to inhibit 11,-HSD1 activity by 39.49% in a cellular enzyme assay. Finally, NG showed a Medium Lethal Dose LD50 > 5000 mg/kg and ranking at level five based on OECD protocols. Conclusion:, Our findings suggest that NG may exert its antidiabetic effect by extra-pancreatic action and by suppressing carbohydrate absorption from intestine, thereby reducing the postprandial increase in blood GLU levels. [source] Ghrelin: a new peptide regulating the neurohormonal system, energy homeostasis and glucose metabolismDIABETES/METABOLISM: RESEARCH AND REVIEWS, Issue 5 2008Peter Pusztai Abstract Identification of ghrelin started with the discovery of growth hormone secretagogues, continued with the description of ghrelin receptors and ended with the elucidation of the chemical structure of ghrelin. However, several issues concerning the role of ghrelin in physiological and pathophysiological processes are still under investigation. Most of the ghrelin produced in the body is secreted in the stomach, but it is also expressed in the hypothalamus, pituitary, pancreas, intestine, kidney, heart and gonads. Ghrelin stimulates growth hormone secretion via growth hormone secretagogue receptors. Ghrelin secretion in the stomach depends on both acute and chronic changes in nutritional status and energy balance. Current data support the hypothesis that the stomach, in addition to its important role in digestion, not only influences pituitary hormone secretion but, via ghrelin production, it also sends orexigenic (appetite increasing) signals to hypothalamic nuclei involved in the regulation of energy homeostasis. In addition to these main effects, ghrelin influences insulin secretion and glucose metabolism and it may exert potentially important effects on cardiovascular and gastrointestinal functions. Because of its effects on a large number of physiological functions, ghrelin may be involved in the pathomechanism of several human disorders, including disturbances of appetite, energy homeostasis and glucose metabolism. Further research might lead to a better understanding of the pathophysiology of ghrelin and might provide more effective therapy for the above disorders. Copyright © 2008 John Wiley & Sons, Ltd. [source] Therapy of type 2 diabetes mellitus based on the actions of glucagon-like peptide-1DIABETES/METABOLISM: RESEARCH AND REVIEWS, Issue 6 2002Jens Juul Holst Abstract GLP-1 is a peptide hormone from the intestinal mucosa. It is secreted in response to meal ingestion and normally functions in the so-called ileal brake, that is, inhibition of upper gastrointestinal motility and secretion when nutrients are present in the distal small intestine. It also induces satiety and promotes tissue deposition of ingested glucose by stimulating insulin secretion. Thus, it is an essential incretin hormone. In addition, the hormone has been demonstrated to promote insulin biosynthesis and insulin gene expression and to have trophic effects on the beta cells. The trophic effects include proliferation of existing beta cells, maturation of new cells from duct progenitor cells and inhibition of apoptosis. Furthermore, glucagon secretion is inhibited. Because of these effects, the hormone effectively improves metabolism in patients with type 2 diabetes mellitus. Thus, continuous subcutaneous administration of the peptide for six weeks in patients with rather advanced disease greatly improved glucose profiles and lowered body weight, haemoglobin A1C, and free fatty acids (FFA). In addition, insulin sensitivity doubled and insulin responses to glucose were greatly improved. There were no side effects. Continuous administration is necessary because of rapid degradation by the enzyme dipeptidyl peptidase-IV. Alternative approaches include the use of analogues that are resistant to the actions of the enzyme, as well as inhibitors of the enzyme. Both approaches have shown remarkable efficacy in both experimental and clinical studies. The GLP-1-based therapy of type 2 diabetes, therefore, represents a new and attractive alternative. Copyright © 2002 John Wiley & Sons, Ltd. [source] Dorothy Hodgkin Lecture 2008 Gastric inhibitory polypeptide (GIP) revisited: a new therapeutic target for obesity,diabetes?DIABETIC MEDICINE, Issue 7 2008P. R. Flatt Abstract There is increasing realization that gastric inhibitory polypeptide (GIP) has actions outside of the pancreas and gastrointestinal tract. Most significant is the presence of functional GIP receptors on adipocytes and the appreciation that GIP, secreted strongly in response to fat ingestion, plays a role in the translation of excessive amounts of dietary fat into adipocyte tissue stores. Such effects open up the possibility of exploiting GIP receptor antagonism for the treatment of obesity and insulin resistance. This is borne out by studies in high-fat-fed mice or ob/ob mice with either genetic knockout of GIP receptor or chemical ablation of GIP action using the GIP receptor antagonist, (Pro3)GIP. By causing preferential oxidation of fat, blockade of GIP signalling clears triglyceride deposits from liver and muscle, thereby respectively restoring mechanisms for suppression of hepatic glucose output and cellular glucose uptake. Further studies are needed to determine the applicability of this research to human obesity,diabetes. However, proof of concept is provided by emerging evidence that rapid cure of diabetes in grossly obese subjects undergoing Roux-en-Y bypass surgery is mediated in part by surgical bypass of GIP-secreting K-cells in the upper small intestine. [source] Gastric emptying in diabetes: clinical significance and treatmentDIABETIC MEDICINE, Issue 3 2002M. Horowitz Abstract The outcome of recent studies has led to redefinition of concepts relating to the prevalence, pathogenesis and clinical significance of disordered gastric emptying in patients with diabetes mellitus. The use of scintigraphic techniques has established that gastric emptying is abnormally slow in approx. 30,50% of outpatients with long-standing Type 1 or Type 2 diabetes, although the magnitude of this delay is modest in many cases. Upper gastrointestinal symptoms occur frequently and affect quality of life adversely in patients with diabetes, although the relationship between symptoms and the rate of gastric emptying is weak. Acute changes in blood glucose concentration affect both gastric motor function and upper gastrointestinal symptoms. Gastric emptying is slower during hyperglycaemia when compared with euglycaemia and accelerated during hypoglycaemia. The blood glucose concentration may influence the response to prokinetic drugs. Conversely, the rate of gastric emptying is a major determinant of post-prandial glycaemic excursions in healthy subjects, as well as in Type 1 and Type 2 patients. A number of therapies currently in development are designed to improve post-prandial glycaemic control by modulating the rate of delivery of nutrients to the small intestine. [source] BLUE RUBBER BLEB NEVUS SYNDROME: TREATMENT OF MULTIPLE GASTROINTESTINAL HEMANGIOMAS WITH ARGON PLASMA COAGULATORDIGESTIVE ENDOSCOPY, Issue 1 2009Enders K.W. Ng Blue rubber bleb nevus syndrome is a rare clinical entity characterized by the formation of multiple blue or purplish rubbery cavernous hemangiomas on the skin and other epithelial surfaces. Involvement of the gastrointestinal tract is common and often presents with crippling anemia as a result of chronic occult blood loss. While surgical extirpation is an option for symptomatic hemangiomas in the intestine, endoscopic therapy is more appealing for lesions found in the stomach and colon. Here we report the successful use of argon plasma coagulation in the management of an adult with multiple hemangiomas in her colon and terminal ileum. [source] PEUTZ-JEGHERS SYNDROME ASSOCIATED WITH RENAL AND GASTRIC CANCER THAT DEMONSTRATED AN STK11 MISSENSE MUTATIONDIGESTIVE ENDOSCOPY, Issue 4 2006Hiromi Kataoka A 75-year-old male was admitted to the gastroenterology unit of Nagoya City University Hospital due to epigastralgia after surgical treatment for right renal cancer. Endoscopy revealed advanced type 1 gastric cancer in the corpus of the stomach and multiple polypoid lesions in the stomach and duodenum. X-ray examination of the small intestine using barium showed multiple polyps in the upper jejunum. Faint pigmentation on the palm was also detected. Peutz-Jeghers syndrome (PJS) was diagnosed, despite a lack of family history. Total gastrectomy, resection of part of the upper jejunum and intraoperative endoscopic polypectomy of duodenal polyps was performed. This is the second reported case of PJS associated with renal cancer. We also detected a missense mutation in the tumor suppressor gene STK11 that, when mutated, is causative for PJS. [source] | |||||||||||||||||||||||||||||||||||||||||||