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Small intestinal perforation and peritonitis after abdominal suction lipoplasty.

Suction lipoplasty for abdominal contouring in nonoperated patients is considered a safe procedure with a low incidence of local and systemic complications. Suction lipoplasty combined with a full abdominoplasty is, however, still controversial with a higher rate of local complications. A 56-year-old woman with a history of four laparotomies and two abdominoplasties was hospitalized with abdominal pain and signs of peritonitis after an ambulatory suction lipoplasty. During laparotomy for peritonitis the abdominal wall was found to be stiff and fibrotic, with massive adhesions to the intestine. Two small intestinal perforations caused soiling into the peritoneum. The perforated intestinal segment was resected and the postoperative history was uneventful. Both recent and former laparotomies in the lower abdomen represent a possible risk when suction lipoplasty is performed. An ultrasonographic or computed tomographic scan of the abdominal wall would identify or rule out any underlying fascial defect or hernia.

Abdominal Muscles↗

Adaptive responses to pharmacological inhibition of small intestinal alpha-glucosidases in the rat.

Intestinal adaptation (small intestinal weight and length, weight of the caecum and of the residual colon) to feeding different doses (0-5-50-500 mg/kg bw) of the absorbable, competitive alpha-glucosidase inhibitors BAY m 1099 and BAY o 1248 for three, seven, or 28 days was studied in rats. With the highest dose of either inhibitor, a significant and time dependent growth of the caecum was observed. Under these conditions, caecal tissue polyamine concentrations (spermidine and spermine) were slightly higher after three, unaffected after seven and slightly decreased after 28 days. Comparing the trophic effect both of BAY m 1099 and BAY o 1248 with that of the almost unabsorbed glucosidase inhibitor acarbose in fed rats showed that caecal weight was higher in response to the absorbed compounds than in response to acarbose, while total caecal carbohydrate content was unaffected by the absorbed and about nine fold increased by the unabsorbed inhibitors. These findings suggest that acarbose may partially inhibit bacterial carbohydrate degradation in the caecum.

1-Deoxynojirimycin↗

Insulin-like growth factor-I improves mucosal structure and function in transplanted rat small intestine.

The transplanted small intestine develops significant mucosal atrophy, impaired nutrient and water absorption, and increased bacterial translocation to mesenteric lymph nodes in rats maintained on elemental diets or total parenteral nutrition. This study determined the effects of administration of an peptide growth factor (insulin-like growth factor-I[IGF-I]) on the mucosal structure and barrier function of rat small bowel isografts. Thirty-six adult Lewis rats underwent either resection of the distal 60% of the small bowel and proximal colon followed by a 40-cm orthotopic jejunal isograft or proximal small bowel transection and distal small bowel resection to leave an analogous length of small intestine in control animals. All rats received an isocaloric, isonitrogenous, polymeric diet (200 kcal/kg/day, 2 gN/kg/day) by gastrostomy and were infused with either IGF-I (2.4 mg/kg/day) or vehicle by osmotic pumps subcutaneously. After 10 days of treatment, jejunal crypt cell production, mucosal morphometric indices, glucose and water absorption, body weight, and bacterial translocation to mesenteric lymph nodes (MLN) were measured. Jejunal mRNA content for IGF-I, IGF-I receptor, and IGF-binding proteins 3 and 4 (IGFBP-3,4) were determined by Northern blotting. Crypt cell production, villus height, crypt depth, and villus surface area were significantly increased in control and transplanted jejunum of rats infused with IGF-I when compared to animals given vehicle alone. Additionally, jejunal glucose absorption and water absorption were significantly improved in both IGF-I groups when compared with their respective vehicle controls. IGF-I infusion increased body weight in transplanted and control animals and markedly reduced bacterial translocation to MLN after small bowel transplantation. Jejunal levels of IGF-I mRNA were significantly increased in transplanted animals when compared to transected controls. IGF-I treatment significantly increased IGFBP-3 tissue mRNA levels in both transected and transplanted animals. These results demonstrate that IGF-I administration, after small bowel transplantation, improves mucosal structure and absorptive function and reduces bacterial translocation to MLN. IGF-I may have important effects in transplanted small bowel both as an endogenous and administered growth factor.

Animals↗

Xylanase and beta-glucanase supplementation improve conjugated bile acid fraction in intestinal contents and increase villus size of small intestine wall in broiler chickens fed a rye-based diet.

This study was performed with growing chickens (4 to 22 d of age) to evaluate the effects of feeding a rye-based diet supplemented with commercial enzyme preparation containing xylanase and beta-glucanase (Quatrazyme HP, Nutri-Tomen, France) on small intestine wall morphology, bile acid composition, nutrient digestibility, and bird performance compared with unsupplemented rye- or corn-based diets. The rye-based diet decreased (P < or = 0.05) weight gain, feed intake, and feed efficiency and increased water intake compared with the corn-based diet. Moreover, rye consumption reduced crude fat and protein digestibility as well as apparent metabolizable energy (P < or = 0.05). The small intestine wall showed that villus length, width, and surface were decreased in broiler chickens fed the rye-based diet compared with those fed the corn-based diet. However, crypt morphometry parameters were not affected by diet type. The concentration of conjugated bile acids in the small intestine contents of broiler chickens fed the rye-based diet was decreased (P < or = 0.05) compared with those fed the corn-based diet. These findings suggest that feeding a rye-based diet reduces villus capacity for nutrient absorption and bile acid capacity for fat solubilization and emulsification, resulting in decreased bird performance. The addition of xylanase and beta-glucanase to the rye-based diet improved (P < or = 0.05) weight gain, feed intake, and feed efficiency, and decreased water intake. The digestibility of nutrients and apparent metabolizable energy were also increased (P < or = 0.05). Addition of xylanase and beta-glucanase increased (P < or = 0.05) villus size and the villus height-to-crypt depth ratio, as well as the concentration of conjugated bile acids (P < or = 0.05) in the small intestine contents. Exogenous enzymes improved nutrient digestibility and broiler chicken performance, probably by improving the absorption capacity ofthe small intestine through increased villus surface and intestinal concentration of conjugated bile acids.

Animal Feed↗

Membrane conductance and cell volume changes evoked by vasoactive intestinal polypeptide and carbachol in small intestinal crypts.

We have used the perforated-patch whole-cell recording mode of the patch-clamp technique to monitor membrane potential and measured cell volume changes by image analysis, to determine the nature of the response to secretagogues of isolated whole guinea-pig small-intestinal crypts. Vasoactive intestinal polypeptide (VIP) produced a dose-dependent depolarisation (EC50 = 30 nM) and an increase in membrane conductance that could be potentiated by carbachol. Similar depolarisations were observed with forskolin. The depolarisation induced by 100 nM VIP was smaller when pipette [Cl-] was 60 mM than when it was 145 mM, suggesting an effect through Cl- conductance activation. Carbachol alone produced a hyperpolarisation (EC50 = 2 microM). The Cl- channel blocker 5-nitro-2-(3-phenylpropylamino)-benzoic acid (NPPB) produced a small hyperpolarization. When VIP was added in the presence of NPPB, the depolarisation was observed instead, consistent with the parallel activation of a K+ conductance. Both carbachol (100 microM) and VIP (100 nM) induced a 25%-30% shrinkage of crypts, which was maximal 8 min after addition of the secretagogue. The induced shrinkage was sustained in the continued presence of agonist and was reversed upon washout. Shrinkage induced by the agonists was abolished by increasing extracellular K+ from 6 mM to 20 mM and was inhibited partially in the presence of 100 microM anthracene-9-carboxylic acid in the bath. The decrease in volume induced by 100 nM VIP was totally abolished in the presence of 100 microM NPPB. The results are consistent with the view that both VIP and carbachol induce secretion in small-intestinal crypts.

Animals↗

Effects of restricted diet and intestinal flora on the life span of small intestine epithelial cells in mice.

Previous data have shown that the life span of small intestine epithelial cells in germ-free (GF) mice was 4.3 days, while that in conventional (CV) mice was 2.1 days, under ad libitum feeding. On the other hand, in the author's laboratory, it was also found that feeding conditions affected the cells' life span. That is, in CV mice the life span of the cells lengthened under restricted feeding (2.6 days), compared with under and libitum feeding (1.8 days). In the present experiment the life span of small intestine epithelial cells was investigated using radioautography, under controlled feeding (setting it equal to ad libitum feeding) and restricted feeding, in both CV and GF mice. Small intestine samples were taken from the middle part of duodenum, jejunum and ileum. Body weight changes, organ wet weights and intestine were also measured. In the lower part of the small intestine the effects of a restricted diet on epithelial cell life span prolongation appeared clearly in CV mice, but this effect was reduced in GF mice. This may be partly because the restricted group had slightly shorter villi in the case of GF mice.

Animals↗

A novel marker glycoprotein for the microvillus membrane of surface colonocytes of rat large intestine and its presence in small-intestinal crypt cells.

Murine mAbs were produced against purified microvillus membranes of rat colonocytes in order to establish a marker protein for this membrane. The majority of antibodies binding to the colonic microvillus membrane recognized a single protein with a mean apparent Mr of 120 kD in both proximal and distal colon samples. The antigen is membrane bound as probed by phase-partitioning studies using Triton X-114 and by the sodium carbonate extraction procedure and is extensively glycosylated as assessed by endoglycosidase F digestion. Localization studies in adult rats by light and electron microscopy revealed the microvillus membrane of surface colonocytes as the principal site of the immunoreaction. The antigen was not detectable in kidney or liver by immunoprecipitation but was present in the small intestine, where it was predominantly confined to the apical membrane of crypt cells and much less to the microvillus membrane of differentiated enterocytes. During fetal development, the antigen appears first in the colon at day 15 and 1-2 d later in the small intestine. In both segments, it initially covers the whole luminal surface but an adult-like localization pattern develops soon after birth. The antibodies were also used to develop a radiometric assay for the quantification of the antigen in subcellular fractions of colonocytes in order to assess the validity of a previously developed method for the purification of colonic brush-border membranes (Stieger, B., A. Marxer, and H.P. Hauri. 1986. J. Membr. Biol. 91:19-31.). The results suggest that we have identified a valuable marker glycoprotein for the colonic microvillus membrane, which in adult rats may also serve as a marker for early differentiation of enterocyte progenitor cells in small-intestinal crypt cells.

Age Factors↗

Effect of morphine sulfate on intestinal transit and myoelectric activity of the small intestine of the rat.

A study was designed to determine the effects of morphine sulfate on small intestinal propulsion and small intestinal myoelectric activity in conscious rats. Adult male rats were divided into two groups. Each member of one group was implanted with an indwelling catheter in the proximal duodenum. Each member of the other group was implanted with electrodes on the serosal surface of the proximal small bowel. Intestinal transit was determined by administering a bolus of radioactive chromium (Na2 51CrO4, 0.5 muCi) in 0.2 ml of saline via the catheter and following its progression through the small intestine. In fasted rats, morphine sulfate administered s.c. inhibited intestinal transit of 51Cr in a dose-dependent manner between 1 and 25 mg/kg. Intestinal motility was determined by monitoring intestinal myoelectric activity both before and after administration of morphine sulfate. In fasted rats, s.c. administration of morphine caused an inhibition of spike potential activity. The inhibition was dose-dependent between dosages of 1 and 25 kg/kg. We conclude that morphine sulfate causes a dose-dependent inhibition of intestinal transit in fasted rats and that this inhibition is correlated with a dose-dependent inhibition of spike potentials of the intestinal smooth muscle cells.

Action Potentials↗

CT of the small intestine.

CT of the small intestine continues to be a diagnostic challenge. Three protocols have turned out to be useful. The frequently used general protocol is highly suitable for most indications that require an overview of the small intestine and in cases where no specific queries regarding the small intestine have to be answered. A dedicated protocol with opacification of the small intestine by means of a probe appears to be useful in patients with a suspected tumour or to exclude a tumour as well as in cases of inflammatory bowel disease. Filling of the bowel ensures optimal distention and, in combination with intravenous contrast medium administration, allows differentiation of tumours from inflammatory lesions. In cases of suspected intestinal ischaemia, angiographic techniques should be used. State-of-the-art techniques such as bolus tracking and acquisition of a dynamic scan for determination of individual circulation time facilitate optimal arterial opacification of the intestinal wall. The results obtained in our patients suggest that the use of multislice CT in combination with optimal opacification improves sensitivity. Further studies have to show whether the improved diagnostic options also translate into an improved clinical outcome or survival rate.

Clinical Protocols↗

Small intestinal physiology and pathophysiology.

The small intestine, like the rest of the gastrointestinal tract, is an intelligent organ. It generates a wide variety of motor patterns to meet motility requirements in different situations. Its basic motor function after a meal is to mix the chyme with exocrine and intestinal secretions, agitate its contents to uniformly and evenly expose them to the mucosal surface, and to propel them distally at a rate that allows optimal absorption of food components, and reabsorption of bile. Most of these functions are performed by individual phasic contractions. In humans, the phasic contractions are largely disorganized in time and space. These contractions may cause mixing and agitation of luminal contents with slow distal propulsion. Occasionally, an individual contraction of large amplitude and long duration migrates over several centimeters and may rapidly propel the contents over this distance. In general, the spatial and temporal relationships of individual phasic contractions become less organized distally, resulting in a slower propulsion rate in the distal small intestine than in the proximal small intestine. The migrating clustered contractions generated after a meal may also be propulsive, but because of their unpredictable and irregular occurrence, their precise role in postprandial propulsion is incompletely understood. Rapidly migrating contractions may occur when the electrical control activity is obliterated by pharmacologic agents or during parasitic infections. Their effects on motility are not known yet. Between meals, when digestion is complete, the small intestine generates migrating motor complexes that help keep the small intestine clean by dislodging debris from the villi and dumping them into the colon. This may prevent decay of these materials in the small intestine and limit their contribution to bacterial overgrowth. Giant migrating contractions may perform a similar function in the distal small intestine as well as return any refluxed fecal material back to the colon. However, the major role of giant migrating contractions may be, in pathologic states, associated with abdominal cramping and diarrhea. Giant migrating contractions are associated with mass movements. Vomiting is preceded by a retrograde giant contraction. This contraction rapidly empties the contents of the proximal half of small intestine into the stomach in preparation for vomitus expulsion by contraction of abdominal and diaphragmatic muscles. The three basic mechanisms of control of spatial and temporal patterns of contractions are myogenic, neural, and chemical.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

Acute intestinal obstruction due to intramural haemorrhage in small intestine in a patient with severe haemophilia A and inhibitor.

Patients with severe haemophilia A usually present with joint, gastrointestinal and urinary tract haemorrhage. Bleeding elsewhere is often precipitated by pre-existing pathology or trauma. We report a patient with severe haemophilia A, who presented with symptoms of acute intestinal obstruction. He has a factor VIII inhibitor and receives recombinant factor VIIa on demand at home. The CT scan of abdomen showed dilated small intestine with fluid filled loops and a long segment in the jejunum with marked transmural thickening. There was no other pathology in the small intestine. These appearances were consistent with intramural haemorrhage in the small intestine as the cause of acute obstruction. He was managed conservatively with recombinant factor VIIa and this resulted in resolution of his symptoms. This case highlights an unusual presentation of bleeding in a haemophilia patient. Intestinal obstruction due to haemorrhage in the small intestinal wall is extremely rare and only previously reported in a few haemophilia patients. It also highlights the effectiveness of conservative management with recombinant factor VIIa as opposed to immediate exploratory surgery.

Acute Disease↗

[Pathology of small intestine transplantation].

Small bowel transplantation is being increasingly performed to treat patients with irreversible intestinal failure or short bowel syndrome. Worldwide approximately 100 transplantations are currently performed per year. Technical advances and new immunosuppressive strategies adopted during the last 10 years have significantly improved the quality of live and survival rate of the patients. The 5-year survival rate is currently around 60%. However, the procedure still bears significant live threatening risks. Mayor problems include surgical complications like anastomotic leakage or peritonitis, acute allograft rejection, systemic infection and in later stages loss of graft function due to chronic rejection. Acute rejection is common after intestinal transplantation. It may occur any time after transplantation and is seen in 50%-80% of the patients. The characteristic changes are enterocyte apoptosis in the crypts, cryptitis and mononuclear cell infiltration with activated lymphocytes. Severe cases may reveal ulcerations or even sloughing and widespread exfoliation of the epithelium and are almost invariably associated with graft loss. The histopathological abnormalities may be patchy and occur in grossly normal mucosa. Therefore, multiple biopsies should be generally sampled for histology. Acute rejection must be distinguished from infections in particular opportunistic viral infections caused by Cytomegalovirus (CMV) or Adenovirus as well as from Epstein-Barr virus-related B-lymphocyte proliferations. Differential diagnosis also includes preservation injury and ischemia resulting in damage of the mucosal surface epithelium. Long-term graft function and survival are now increasingly determined by chronic rejection. The hallmarks of chronic rejection are obliterative arteriopathy of mesenterial vessels and progressive fibrosis of the transplant including its mesentery.

Graft Rejection↗

Autoradiographic distribution of vasoactive intestinal polypeptide receptors in rabbit and rat small intestine.

Vasoactive intestinal peptide (VIP) is found in the enteric nervous system of all layers of the small intestine. In the gastrointestinal tract, VIP receptors coupled to adenylate cyclase are present on epithelial, smooth muscle and possibly mononuclear cells. This study analyzes the distribution of VIP binding using in vitro autoradiographic techniques. VIP binding was present in high density in the mucosal layer of rabbit duodenum, jejunum and ileum. Low VIP binding was noted over the smooth muscle layers or the lymphoid follicles. Similar results were obtained in rat small intestine. The density of VIP binding was greatest in duodenal mucosa but was present in lower density in jejunal and ileal mucosa. Again, low VIP binding was noted in the smooth muscle layers or lymphoid follicles. Thus, autoradiographic maps of small intestine indicate that VIP receptors are found primarily in the small intestinal mucosa.

Animals↗

[An additional use of the small intestinal invagination valve].

Extensive small intestine resection (70--90%) as should be done after mesenteric infarction produces a chronic malabsorption syndrome with its consequences. Applying an invagination valve of the small intestine (Kock) and using the isoperistaltic modification, passage of the chyme is delayed and its resorption improved. A small intestine resection of 90% was done in 8 mongrel dogs. After an average of 2--3 months an obvious cachexia as well as a steatorrhea could be observed. By adapting an isoperistaltic small intestine invagination valve near the colon weight reduction could be stopped during another 6 months and the steatorrhea disappeared No ileus occured.

Animals↗

Electrical stimulation of small intestinal electrical control activity.

The small intestinal electrical control activity (ECA) was driven by an electrical stimulus and the resultant effects on the frequency and the phase relationships of control waves recorded. The small intestinal ECA can be driven from all sites from which it could be recorded. The mean maximum driven frequency (MDF) was the highest near the pylorus and it decreased distally, but at any given site it was the same before and after dividing the small intestine into small segments. The length of the frequency plateau decreased and phase lag per cm increased with an increase in plateau frequency. The direction of phase lag was orad proximal to a stimulation site and aborad distal to it. Intravenous atropine (up to 100 mug per kg) or reserpinization of dogs before an experiment had no effect on the MDF in the frequency plateau region. The study confirms the validity of an array of bidirectionally coupled relaxation oscillators as a model of small intestinal ECA and shows that the frequency and the phase relationship of small intestinal control waves can be altered by electrical stimulation. The study also points out some differences between the small intestinal and gastric ECA's at the cellular level.

Animals↗