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PubMed2007

Quantitative evaluation of adhesion of lactobacilli isolated from human intestinal tissues to human colonic mucin using surface plasmon resonance (BIACORE assay).

AIMS: To isolate lactobacilli from the mucus layer of the human intestine and evaluate their adhesion abilities using a BIACORE assay. METHODS AND RESULTS: Thirty strains of lactobacilli were isolated from the mucus layer of normal human intestinal tissues using conventional plate culture. The strains were identified using homology comparisons of the 16S rDNA sequence to databases as Lactobacillus salivarius (26%), Lactobacillus fermentum (13%), Lactobacillus gasseri (10%), Lactobacillus paracasei (7%), Lactobacillus casei (3%), Lactobacillus mucosae (3%) and Lactobacillus plantarum (3%). Lactobacillus plantarum LA 318 shows the highest adhesion to human colonic mucin (HCM) using the BIACORE assay at 115.30 +/- 12.37 resonance unit (RU). The adhesion of cell wall surface proteins from strain LA 318 was significantly higher to HCM than to bovine serum albumin (BSA; P < 0.05). CONCLUSIONS: We isolated 30 strains of lactobacilli. Lactobacillus salivarius was the predominant species of lactobacilli isolated in this study. The adhesion of strain LA 318 isolated from human transverse colon to its mucin was shown. The adhesion could be mediated by lectin-like components on the bacterial cell surface. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first study where lactobacilli were isolated from human intestinal tissues and shown to adhere to HCM.

Bacterial Adhesion↗
PubMed1998

[Surgical therapy of ileus of the large intestine].

Acute colonic obstruction is a life threatening emergency. In this prospective study 69 patients suffering from large bowel obstruction, admitted between November 1993 and March 1998 to the University hospital of Bern, were analyzed with regard of the performed surgical procedure. The causes of obstruction were colorectal carcinomas (38%), other malignancies (19%), volvulus (13%), hernias (10%), diverticulitis (7%) and others (13%), 8 benign and 19 malignant lesions were surgically treated without colonic resection, the latter by colostomy (13), ileostomy (5) or bypass (1). All the other 42 patients had their obstruction resected within 24 hours after admission, 24 of them with primary anastomosis and 18 as a two-staged procedure. However, 9/18 (50%) patients never have had restoration of bowel continuity. No three-stage procedure was planned or performed. In-hospital mortality was 4/69 (5.8%), all of them after staged resections due to non-surgical complications. No anastomotic leakage was clinically apparent, neither in one-stage procedures, nor in completed two-stage procedures. Median length of total hospital stay in one-stage and two-stage procedures was 14 and 30 days, respectively. The advantages of one-stage procedures, especially in terms of subtotal colectomy, are discussed on the basis of an overview of the literature.

Acute Disease↗
PubMed2002

A novel colonic repressor element regulates intestinal gene expression by interacting with Cux/CDP.

Intestinal gene regulation involves mechanisms that direct temporal expression along the vertical and horizontal axes of the alimentary tract. Sucrase-isomaltase (SI), the product of an enterocyte-specific gene, exhibits a complex pattern of expression. Generation of transgenic mice with a mutated SI transgene showed involvement of an overlapping CDP (CCAAT displacement protein)-GATA element in colonic repression of SI throughout postnatal intestinal development. We define this element as CRESIP (colon-repressive element of the SI promoter). Cux/CDP interacts with SI and represses SI promoter activity in a CRESIP-dependent manner. Cux/CDP homozygous mutant mice displayed increased expression of SI mRNA during early postnatal development. Our results demonstrate that an intestinal gene can be repressed in the distal gut and identify Cux/CDP as a regulator of this repression during development.

Aging↗
PubMed2003

Dextran sulfate sodium-induced inflammation is enhanced by intestinal epithelial cell chemokine expression in mice.

Dextran sulfate sodium (DSS) induces an inflammatory bowel disease-like colitis in animals. To determine the contribution of epithelium to inflammation in the intestine, we examined the effects of DSS in transgenic mice that specifically secrete macrophage inflammatory protein-2 (MIP-2) from the intestinal epithelium. We first confirmed the production of MIP-2 from intestinal epithelial cells by Western blots in transgenic mice. MIP-2 transgenic mice were therefore an appropriate model to examine the role of epithelial cell chemokines in an inflammatory state induced by DSS. We then examined the neutrophil migration into the intestine and the effect of DSS on this migration by myeloperoxidase staining. There was an increase of myeloperoxidase-positive neutrophils in the intestine from wild-type and transgenic mice after the DSS treatment. Furthermore, the increase of neutrophils under stimulation with DSS was confirmed quantitatively by measuring specific tissue myeloperoxidase activities. It was significantly greater in DSS-treated MIP-2 transgenic mice than in wild-type mice in both the small intestine and colon. These results suggest that the inflammatory effects of DSS on both small intestine and colon are enhanced by MIP-2 secreted by epithelial cells in the transgenic mice. In conclusion, intestinal epithelial cells can act in concert with other inflammatory stimuli in maintaining inflammation.

Animals↗
PubMed2002

Use of immunoglobulin enriched bovine colostrum against oral challenge with enterohaemorrhagic Escherichia coli O157:H7 in mice.

An immunoglobulin enriched bovine colostrum preparation, IMMULAC (New Zealand Dairy Group, Cambridge, New Zealand), contains antibodies against various bacterial antigens. In the present study, we investigated the protective effects of a commercial bovine colostrum preparation against infections with enterohaemorrhagic Escherichia coli (EHEC) O157:H7 in a murine model. Balb/c mice were given drinking water containing streptomycin for 3 days before and following oral challenge with streptomycin-resistant EHEC O157:H7 strain (O157-SM(R)). In mice pretreated with streptomycin, EHEC O157:H7 maintained stable levels of bacterial colonization in the intestines for the 3-week experimental time period. Oral administration of colostrum resulted in rapid decrease in the bacteria numbers compared with administration of skim-milk. Colostrum showed no direct in vitro bactericidal properties against either EHEC O157:H7. When sections prepared from cecum walls of streptomycin-pretreated mice were incubated in vitro with EHEC O157:H7, the colostrum significantly prevented the attachment of the organisms to the sections when compared with skim-milk. These results indicate that oral administration of bovine colostrum effectively protects mice against food-borne infections by inhibiting bacterial attachment to the intestinal mucous membrane, colonization and growth in the intestinal tract.

Aging↗
PubMed2005

Expression and localization of Reg IV in human neoplastic and non-neoplastic tissues: Reg IV expression is associated with intestinal and neuroendocrine differentiation in gastric adenocarcinoma.

Regenerating islet-derived family, member 4 (Reg IV) is a candidate marker for cancer and inflammatory bowel disease. In the present study, immunohistochemical analysis of Reg IV was performed in various human neoplastic (n = 289) and non-neoplastic tissues. In the stomach, foveolar epithelium was negative for Reg IV, whereas goblet cells of intestinal metaplasia and neuroendocrine cells at the base of intestinal metaplasia expressed Reg IV. Neuroendocrine cells of the small intestine and colon showed strong expression of Reg IV, whereas goblet cells of the small intestine and colon showed weak or no expression of Reg IV. Insulin-producing beta cells of the endocrine pancreas were positive for Reg IV. Among 143 gastric adenocarcinomas, Reg IV expression was detected in 42 (29.4%) and was associated with both the intestinal mucin phenotype and neuroendocrine differentiation. No association was found between Reg IV expression and clinical characteristics such as tumour stage and patient prognosis. Of 36 colorectal adenocarcinomas, 13 (36.1%) were positive for Reg IV, which was associated with tumour stage (p = 0.0379, Fisher's exact test). Expression of Reg IV was detected in 14 (93.3%) of 15 colorectal carcinoid tumours. Reg IV expression was also detected in 5 (21.7%) of 23 ductal adenocarcinomas of the pancreas. In contrast, lung cancers (n = 30) and breast cancers (n = 30) did not express Reg IV. This is the first immunohistochemical analysis of the expression and distribution of Reg IV protein in human tumours. These data suggest that Reg IV is expressed by gastrointestinal and pancreatic tumours, including adenocarcinomas and carcinoid tumours, and that Reg IV is associated with intestinal and neuroendocrine differentiation of the stomach and gastric carcinoma.

Adenocarcinoma↗
PubMed1996

Gastrointestinal tract protein synthesis and mRNA levels for proteolytic systems in adult fasted rats.

We studied protein turnover in the gastrointestinal tract of adult fasted rats, since the mechanisms responsible for protein wasting in these tissues are poorly understood. Protein mass of stomach, small intestine, and colon decreased by 14-29 and 21-49% after 1 and 5 days of fasting, respectively. The fractional rate of in vivo protein synthesis (ks) was approximately 34% lower in the stomach after 1 and 5 days of fasting due to decreased capacity for protein synthesis (Cs). In small intestine and colon, ks was not different after 1 day, but was approximately 26% lower on day 5, mainly because of a reduction in Cs. Thus protein wasting in the stomach is primarily mediated by decreased protein synthesis but not in small intestine and colon during short-term fasting. To determine which proteolytic systems may be activated in the gut, we measured mRNA levels for critical components of the lysosomal (cathepsins B and D), Ca(2+)-activated (m-calpain), and ubiquitin-dependent (ubiquitin, 14-kDa ubiquitin-conjugating enzyme E2, and C8, and C9 proteasome subunits) proteolytic pathways. mRNA levels for most of these components increased during fasting, suggesting that a coordinated activation of multiple proteolytic systems contributed to intestinal protein wasting.

Animals↗
PubMed1982

Inhibition of methylazoxymethanol-induced intestinal tumors in the rat by pyrazole with paradoxical effects on skin and kidney.

Methylazoxymethanol is a potent carcinogen and induces tumors predominantly of the small intestine and colon following a single injection. Previous data indicated that alcohol dehydrogenase could convert this carcinogen to a reactive alkylating agent. Rats were treated with an inhibitor of this enzyme, pyrazole, 2 hr prior to their receiving the carcinogen. The development of intestinal and colonic tumors was prevented. The rats did, however, develop numerous tumors of the skin and kidney. Analyses of the complete autopsies are presented. The data indicate that intestinal and colonic alcohol dehydrogenase plays a role in the tumorigenic effects of methylazoxymethanol and that other non-pyrazole-sensitive enzymes exist in other organs that can also activate this carcinogen.

Alcohol Oxidoreductases↗
PubMed1995

[Indications for laparoscopic surgery of the large intestine].

Laparoscopic colon resection is feasible but not standardized regarding indication and surgical procedure. Indications are mainly benign diseases (diverticulitis, Crohn's disease, ulcerative colitis and sessile dysplastic polyps or adenomas). Rare indications are benign tumors, angiodysplasia of the colon and dolichocolon. Laparoscopic rectopexy and sutural closure of iatrogenic colon perforation have minimal invasive indication, too. Indication for laparoscopic colon resection for malign tumors in T1-stage is still unclear. Use of minimal invasive procedures for palliative reasons (construction of colostomy or bypass anastomoses in malign tumors) is appropriate. In 32 laparoscopic bowel operations we found no lethality. In 5 cases early conversions to laparotomy were necessary. Postoperatively following complications occurred: 1 intraabdominal bleeding, 1 stenosis of anastomosis and 1 wound infection.

Adult↗
PubMed1997

APC mutation and the crypt cycle in murine and human intestine.

Dysplastic colon adenomas are thought to arise from growth of clones of APC -/- colonic epithelial cells. Isolated clusters of dysplastic crypts are often observed in patients with familial adenomatous polyposis. These patients have genotype APC +/-, and the clusters of dysplastic crypts (called microadenoma or aberrant crypt foci) are thought to represent an early stage in the expansion of a mutant clone of APC -/- cells. It is thought that the growth of these clusters of mutant crypts results from crypt replication through a process similar to what occurs in the normal crypt cycle. We measured the relative replication rate of mutant crypts by analyzing the size of clusters of mutant crypts in APC +/- individuals and found that mutant APC -/- crypts replicate more rapidly than do normal APC +/- (i.e., nonneoplastic) crypts. In contrast, the replication rate of mutant crypts in Apc +/- mice is not significantly different from that of normal crypts, thus supporting previous findings that aberrant crypt foci do not contribute significantly to the colon adenoma population in adult Apc +/- mice. Intriguingly, we found an effect of Apc heterozygosity on the frequency of branching crypts in young mice.

Adenomatous Polyposis Coli↗
PubMed1981

Gastrointestinal tract O2 uptake and regional blood flows during digestion in conscious newborn lambs.

We determined gastrointestinal tract O2 uptake, cardiac output, regional blood flows, and whole-body O2 uptake before and for 1-6 h after feeding in 10 chronically catheterized unanesthetized lambs (9-15 days of age). Total gastrointestinal blood flow (sum of blood flows to the stomach, small intestine, and colon, as calculated with the radioactive microsphere technique) increased 23% at 1 h postprandially. This increased flow at 1 h was due to a large increase in blood flow to the stomach, whereas blood flows to the small intestine and colon did not change significantly. By 2 h, stomach blood flow and thus total gastrointestinal blood flow had returned to fasting values. In contrast, total O2 uptake by the gastrointestinal tract organs (stomach, small intestine, and colon) increased 65% at 1 h, 51% at 2 h, and 28% at 3 h postprandially in association with increases in O2 extraction (O2 uptake/O2 delivery) of 41% at 1 h, 45% at 2 h, and 27% at 3 h. There were no digestion-related changes in whole-body O2 uptake or in cardiac output and its distribution to the brain, heart, kidney, liver (hepatic artery), and carcass. Our data indicate that postprandial increases in O2 demand by gastrointestinal tract organs of the newborn animal are met primarily by enhanced tissue O2 extraction, rather than by metabolic hyperemia, because the postprandial hyperemia observed in the neonate is of short duration and is confined to the stomach.

Animals↗
PubMed1985

Macromolecular transport in the fetal rat intestine.

Macromolecular barrier function of the fetal rat small intestine and colon was analyzed from 16 to 22 days gestation (birth). During this period the epithelium is converted from stratified to simple columnar. To assess permeability, horseradish peroxidase (HRP) was introduced by microinjection into the lumen or into the umbilical circulation. Proximal small intestine, distal small intestine, and colon were examined after 10-20 min. Paracellular passage of HRP through occluding junctions was not observed after either intraluminal or intravascular injection. After intraluminal injection, transepithelial transport of HRP from lumen to blood occurred in all regions at all ages studied. Horseradish peroxidase was present in cytoplasmic vesicles of most cells in the primitive stratified epithelia, during epithelial conversion, and in simple columnar epithelia. After intravascular injection, HRP was present in the lamina propria and in intercellular spaces of the epithelium, but HRP did not enter tight junctions. Tracer was taken up into cytoplasmic vesicles of both stratified and simple columnar epithelial cells, but was only rarely seen in the lumen. We conclude that there is rapid transcellular, vesicle-mediated transport from lumen to blood across both stratified and simple columnar epithelia of fetal rat small intestine and colon; after intravascular injection, macromolecules may be taken up into vesicles at basolateral epithelial cell surfaces but are not rapidly transported into the lumen; paracellular passage does not occur in the fetal ages studied.

Animals↗
PubMed1998

A single rostrocaudal colonization of the rodent intestine by enteric neuron precursors is revealed by the expression of Phox2b, Ret, and p75 and by explants grown under the kidney capsule or in organ culture.

The colonization of the rodent gastrointestinal tract by enteric neuron precursors is controversial due to the lack of specific cellular markers at early stages. The transcription factor, Phox2b, is expressed by enteric neuron precursors (Pattyn et al. Development 124, 4065-4075, 1997). In this study, we have used an antiserum to Phox2b to characterize in detail the spatiotemporal expression of Phox2b in the gastrointestinal tract of adult mice and embryonic mice and rats. In adult mice, all enteric neurons (labeled with neuron-specific enolase antibodies), and a subpopulation of glial cells (labeled with GFAP antibodies), showed immunoreactivity to Phox2b. In embryonic mice, the appearance of Phox2b-immunoreactive cells was mapped during development of the gastrointestinal tract. At Embryonic Days 9.5-10 (E9.5-10), Phox2b-labeled cells were present only in the stomach, and during subsequent development, labeled cells appeared as a single rostrocaudal wave along the gastrointestinal tract; at E14 Phox2b-labeled cells were present along the entire length of the gastrointestinal tract. Ret and p75 have also been reported to label migratory-stage enteric neuron precursors. A unidirectional, rostral-to-caudal colonization of the gastrointestinal tract of embryonic mice by Ret- and p75-immunoreactive cells was also observed, and the locations of Ret- and p75-positive cells within the gut were very similar to that of Phox2b-positive cells. To verify the location of enteric neuron precursors within the gut, explants from spatiotemporally defined regions of embryonic intestine, 0.3-3 mm long, were grown in the kidney subcapsular space, or in catenary organ culture, and examined for the presence of neurons. The location and sequence of appearance of enteric neuron precursors deduced from the explants grown under the kidney capsule or in organ culture was very similar to that seen with the Phox2b, Ret, and p75 antisera. Previous studies have mapped the rostrocaudal colonization of the rat intestine by enteric neuron precursors using HNK-1 as a marker. In the current study, all HNK-1-labeled cells in the gastrointestinal tract of rat embryos showed immunoreactivity to Phox2b, but HNK-1 cells comprised only a small subpopulation of the Phox2b-labeled cells. In addition, in rats, Phox2b-labeled cells were present in advance of (more caudal to) the most caudal HNK-1-labeled cells by 600-700 microm in the hindgut at E15. We conclude that the neural crest cell population that arises from the vagal level of the neural axis and that populates the stomach, midgut, and hindgut expresses Phox2b, Ret, and p75. In contrast, the sacral-level neural crest cells that populate the hindgut either do not express, or show a delayed expression of, all of the known markers of vagal- and trunk-level neural crest cells.

Animals↗
PubMed1998

Effect of feeding of a cholesterol-reducing bacterium, Eubacterium coprostanoligenes, to germ-free mice.

Twelve germ-free mice were used to evaluate the effect of orally administered Eubacterium coprostanoligenes (ATCC 51222) on serum cholesterol concentration. After 1 week of bacterial administration, serum cholesterol concentration of the experimental group (204.9 +/- 5.3 mg/dl, mean +/- SEM) tended to be lower than that of controls (213.7 +/- 5.9 mg/dl, mean +/- SEM). The hypocholesterolemic effect, however, was transient. Greater coprostanol-to-cholesterol ratios in feces of bacteria-fed mice also indicated a transient cholesterol-reducing action of E. coprostanoligenes in the intestine. Eubacterium coprostanoligenes did not colonize the intestine of E. coprostanoligenes-fed mice. Results indicate that the transient occurrence of E. coprostanoligenes in the digestive tract of E. coprostanoligenes-fed mice may decrease plasma cholesterol concentration, but colonization of the tract depends on monoassociation with another bacterium. Results also indicate that feeding of E. coprostanoligenes decreases blood cholesterol concentration.

Animals↗
PubMed1993

[Intestinal occlusion due to a colonic lipoma. Apropos 2 cases].

Lipomas occur through the intestinal tract, from the hypopharynx to the rectum, the colon having the highest incidence, where lipomata are the commonest benign neoplasm after adenomata. Nevertheless they are uncommon. CASE REPORT. 1) A 68-year-old man presented as an emergency with abdominal pain associated with bowel obstruction. He had a 2 to 3 month history of intermittent right-sided abdominal pain, constipation spontaneously resolved. At laparotomy there was a mass of the transverse colon, next hepatic flexure. A right hemicolectomy was performed. The patient made an uneventful recovery. Histologic examination showed a lipoma of the submucosal plane. 2) A 65-year-old man presented as an emergency with lower abdominal pain associated with a prolapsed rectal polyp. He had 1 month history of passing fresh blood per rectum. Ap ast colonoscopy revealed a large polypoid lesion in the descending colon. Transanal examination revealed a polypoid lesion with a maximum diameter of 4 cm, acting as an intussuseptum. Transanal polypectomy was performed. At laparotomy there was an intussuseptum of the descending colon into the rectum: a left hemicolectomy was performed. Histology showed the polyp to be a submucosal lipoma. DISCUSSION. Lipomas are the most common benign nonepithelial tumors of the colon. Lipomata of the large bowel are reported as incidental findings in 0.3-0.5% of cases in large series of autopsies. In the wall of the intestine most lie in the submucosal plane, less frequently they are found in the subserosal plane. The commonest site for symptomatic solitary large bowel lipoma is the ascending colon, including the caecum, followed by the transverse colon, including both hepatic and splenic flexure, descending colon, sigmoid colon and rectum. The peak incidence for lipomata of the large bowel is in fifth-sixth decade. Colonic lipomas are generally asymptomatic but occasionally patients may have intermittent crampy abdominal pain secondary to intussusception of a pedunculated lipoma or with intermittent fresh rectal bleeding. On barium enema lipomas appear circular, ovoid, well demarcated, and smooth. A barium enema showing a relatively radiolucent mass, caused by the radiolucency of fat, is suggestive of a lipoma. The water enema, with water as the contrast agent, accentuates the difference in density between a lipoma and surrounding tissues. Another characteristic feature of lipomas on barium enema is said to be their fluctuation in size and shape during the study: "squeeze sign". Lipomas of the large bowel can be seen, however, by colonoscopy. On computerized tomography scan the lipoma has a uniform appearance and density. In expert hands pedunculated and sessile lesions can be removed endoscopically, but often large bowel lipomata are treated on the basis of a presumptive malignant diagnosis with exploratory laparotomy. CONCLUSION. Colonic lipomas, although unusual, continue to present difficulties in the preoperative differentiation between malignant and benign colonic neoplasm. Two cases of colonic lipomas are reported.

Aged↗
PubMed2006

Up-regulation of CYP26A1 in adenomatous polyposis coli-deficient vertebrates via a WNT-dependent mechanism: implications for intestinal cell differentiation and colon tumor development.

Mutations in the adenomatous polyposis coli (APC) tumor suppressor gene seem to underlie the initiation of many colorectal carcinomas. Loss of APC function results in accumulation of beta-catenin and activation of beta-catenin/TCF-dependent transcription. Recent studies have implicated APC in controlling retinoic acid biosynthesis during normal intestinal development through a WNT-independent mechanism. Paradoxically, however, previous studies found that dietary supplementation of Apc(MIN) mice with retinoic acid failed to abrogate adenoma formation. While investigating the above finding, we found that expression of CYP26A1, a major retinoic acid catabolic enzyme, was up-regulated in Apc(MIN) mouse adenomas, human FAP adenomas, human sporadic colon carcinomas, and in the intestine of apc(mcr) mutant zebrafish embryos. Mechanistically, cyp26a1 induction following apc mutation is dependent on WNT signaling as antisense morpholino knockdown of tcf4 or injection of a dnLEF construct into apc(mcr) mutant zebrafish suppressed expression of cyp26a1 along with known WNT target genes. In addition, injection of stabilized beta-catenin or dnGSK3beta into wild-type embryos induced cyp26a1 expression. Genetic knockdown or pharmacologic inhibition of cyp26a1 in apc(mcr) mutant zebrafish embryos rescued gut differentiation defects such as expression of intestinal fatty acid-binding protein and pancreatic trypsin. These findings support a novel role for APC in balancing retinoic acid biosynthesis and catabolism through WNT-independent and WNT-dependent mechanisms.

Adenomatous Polyposis Coli Protein↗
PubMed1980

Intestinal obstruction due to colonic stricture following neonatal necrotizing enterocolitis.

After resolution of acute necrotizing enterocolitis (NEC), six of 31 surviving infants (19%) developed late ischemic stricture of the colon. Stricture occurred after both medical and surgical treatment for NEC, and in both functional and defunctionalized bowel. In medically-treated infants, the symptoms of intestinal obstruction usually began six to eight weeks after NEC. Surgically-treated infants developed asymptomatic strictures distal to an enterostomy. Barium enema was the appropriate diagnostic study for both groups. Operative management consisted of segmental colonic resection with frequent use of enterostomy. On histopathologic examination, resected strictures showed a spectrum of the reparative process after intestinal ischemia, ranging from obliterative scar to near-normal colon. Because delayed diagnosis led to the death of one of our infants, we recommend a barium enema for early diagnosis of stricture about six weeks after NEC, whether initial treatment was medical or surgical. In a recent infant, two colonic strictures were thus diagnosed and resected prior to development of symptoms of intestinal obstruction.

Colonic Diseases↗