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PubMed1994

Localization of small intestinal bleeding. The role of intraoperative endoscopy.

The preoperative identification of a bleeding site is not always possible, particularly when bleeding originates in the small intestine. Small vascular abnormalities, such as the telangiectatic lesion described in this report, comprise about 40-60% of such cases. Preoperative location using arteriography, radionuclide bleeding scan, and enteroclysis were nondiagnostic. The lesion was demonstrated by intraoperative endoscopy. A segment of small intestine was resected, and the patient made an uneventful recovery.

Aged↗
PubMed1990

[Arterial blood flow changes after hyperthermia on normal liver, normal brain, and normal small intestine].

Arterial blood flow changes are studied after hyperthermia on normal liver, normal brain, and normal small intestine. A small part in left lateral lobe of rat liver was heated by RF capacity heating. Arterial blood flow in heated area of liver decreased to 69.2 +/- 8.1 and 51.3 +/- 6.6 ml/min/100 g dry weight respectively after heating at 43 degrees C for 30 min and 45 min, from 83.1 +/- 2.6 ml/min/100 g dry weight at 37 degrees C. To heat a small part in left hemisphere of rat cerebral tissue, RF interstitial heating device was utilized. Arterial blood flow in heated area increased to 289.1 +/- 41.5 ml/min/100 g dry weight after heating at 42 degrees C for 30 min from 223.6 +/- 18.8 ml/min/100 g dry weight at 37 degrees C. For small intestine heating, water bath was used. Arterial blood flow increased to 6.60 +/- 1.36, 7.44 +/- 1.16, and 11.6 +/- 2.2 ml/min/g dry weight respectively after heating at 39 degrees C, 41 degrees C, and 43 degrees C for 30 min, from 5.04 +/- 0.85 ml/min/g dry weight at 37 degrees C. These data suggest that blood flow changes after hyperthermia differ from tissue to tissue, and require further investigation on the effect of hyperthermia on blood flow changes in liver, brain, small intestine, and other normal tissues.

Animals↗
PubMed1993

Influence of low luminal cadmium-concentrations on transfer of water and cadmium in the rat small intestine in vitro.

The sensitivity of the small intestinal water transfer for cadmium (Cd) exposure and its longitudinal gradient were investigated in luminally perfused intestinal segments in vitro and in vivo. Proximal segments accumulated Cd to a higher extent and, in addition, were more sensitive to Cd exposure than distal segments. In the proximal small intestine Cd impairs the intestinal water transfer at concentrations between 0.1 and 1.0 mumol/l in vitro and 4 mumol Cd/l in vivo. In vitro the Cd transfer from the intestinal tissue into the serosal absorbate declined in parallel to the reduction of the water transfer. In proximal but not in distal segments the declining water transfer corresponded to the decreases in glucose transfer in response to Cd exposure. According to literature the Cd effect on intestinal water transfer may be mediated by interaction of Cd with the Na-glucose co-carrier or by inhibition of the oxidative phosphorylation. The involvement of both mechanisms may differ along the small intestine.

Animals↗
PubMed1990

Regional differences in the appearance of adult-type glycosphingolipids in the small intestine of inbred rats at weaning time.

The small intestine of 15- to 33-day-old rats was cut into four segments: duodenum, proximal jejunum, distal jejunum, and ileum. Neutral glycosphingolipids and gangliosides were purified from each segment and analyzed by thin-layer chromatography in order to study the developmental appearance of adult-type glycolipids at each level of the small intestine. Type 1 A-6 glycolipid was first detected in the ileum at 15 days and subsequently in the jejunum and duodenum at 19 days of age. N-Glycolylneuraminic acid was expressed first in the ileum at 17 days, then in the proximal jejunum at 21 days, but only after 29 days in the duodenum. In each region, 6-8 days were required between first detection and full expression of N-glycolylneuraminic acid. The presence of 2-hydroxylated fatty acids in glucosylceramide was found first in the ileum at 19 days, 2-3 days before appearing in the duodenum and proximal jejunum. A period of 2-3 days was necessary to reach full adult-type level of 2-hydroxylated fatty acids in glucosylceramide. These results show that adult-type glycolipids appear earlier in the distal than in the proximal region of the rat small intestine, and that different glycolipids appear at different times and at different rates. The finding that the biochemical differentiation of the whole small intestine expands over a period of 3 days to 2 weeks, depending on the region and the glycolipid, before being fully completed indicates that, in addition to the time lag observed between the distal and the proximal region, the new cells arising from the crypt of Lieberkhün after 15 days of age are not at once fully differentiated.

ABO Blood-Group System↗
PubMed1975

The effect of raw soya bean on in vitro active and passive accumulation by rat small intestine.

1. Sections of small intestine from rats given raw-soya-bean(RS) diets had a decreased capacity to actively accumulate L-methionine when compared to those taken from rats given heated soya bean (HS), and casein-fed controls. The extent of the reduction was small in comparison with pair-fed animals, but was statistically significant in comparison with rats restricted to the same weight gain as the RS groups. 2. The differences in the passive uptake of D-mannitol appear to be directly related to differences in gut thickness between the control and RS groups. 3. Values for water movement and intestinal transmural potentials further support the results found in the active accumulation studies. 4. From this study it was concluded that the degree of starvation directly affects the magnitude of the effect of RS diets when comparisons are made against adequately fed controls.

Animal Nutritional Physiological Phenomena↗
PubMed1993

Immunoproliferative small intestinal disease (IPSID) in Thailand.

Immunoproliferative small intestinal disease (IPSID) is prevalent in the Mediterranean region and in many Third World countries but is rare in Southeast Asia. Between 1980-1990, 4 cases of IPSID were admitted to Ramathibodi Hospital, Bangkok. Three were males and the mean age was 32 +/- 20.2 years. All patients presented with chronic diarrhea of 7 months to 6 years duration, and weight loss of 15 to 31 kg. All were malnourished, three cachectic, and one patient showed growth retardation. Intestinal parasites were found in all cases: two had multiple infections and three had uncommon protozoal infections (coccidium, cryptosporidium). Barium radiographs revealed intestinal mucosal fold thickening with malabsorption pattern in all cases. Alpha chain IgA was detected in one patient. The remainder underwent exploratory laparotomy and the histological finding was of plasma lymphocytic infiltration of the small intestinal mucosa. All patients responded to oral tetracycline with complete remission occurring in one case. During the follow-up period, 3 cases had progressive retractable clinical courses but all died 2 to 5 years after the diagnosis. The causes of death in these patients were secondary bacterial infection (1 case), intestinal tuberculosis (1 case), fungal infection (1 case) and immunoblastic sarcoma in another case. The results of this study confirm the occurrence of IPSID in Thailand. IPSID responds to oral antibiotic therapy and complete remission may be achieved during the early reversible benign phase, thus an awareness of its occurrence is of clinical importance.

Adolescent↗
PubMed1975

Gastric emptying and small intestinal mucosal injury in rats.

A technique was developed to produce small intestinal mucosal injury in vivo by perfusing the mid-small intestine of rats with HCl, NaOH, FeSO4, and AgNO3. Three hours following injury, gastric emptying and small intestinal transit were measured by examining the gastrointestinal distribution of a non-absorbable radioisotope which had been placed in the stomach for 1 hour. There was a strong association between the villus injury produced by various concentrations of the injurious agents and the degree of gastric retention. Necrosis of villus tips, as produced by AgNO3, was sufficient to cause marked gastric retention. Injury to the small intestinal mucosa of one parabiotic rat did not produce gastric retention in the partner. It is concluded that injury to small intestinal villi is sufficient to induce gastric retention and that the effect is most likely nerve-mediated.

Animals↗
PubMed1988

[Surgical treatment and problem of massive small intestinal resection in children--assessment of background diseases and actual management].

From 1971 to 1986, massive small intestinal resection was done in twenty-five cases; intestinal atresia 12, intestinal volvulus 9, necrotizing enterocolitis 2, intussusception 1 and gastroschisis 1. Thirteen cases (52%) of them have survived. Of 12 cases with intestinal atresia undergoing small intestinal resection, 7 cases had atresias of multiple type, on the other hand, in intestinal volvulus, 4 of 9 cases without malrotation have had massive small intestinal resection, compared with 5 of 30 cases with malrotation. Many clinical problems have occurred after massive small intestinal resection, especially in cases with short bowel syndrome (shorter than 30 cm in length), but home parenteral nutrition has become one of the key treatments for cases with short bowel syndrome.

Child↗
PubMed2002

A dosimetry model for the small intestine incorporating intestinal wall activity and cross-doses.

UNLABELLED: Current internal radiation dosimetry models for the small intestine, and for most walled organs, lack the ability to account for the activity uptake in the intestinal wall. In existing models the cross-dose from nearby loops of the small intestine is not taken into consideration. The aim of this investigation was to develop a general model for calculating the absorbed dose to the radiation-sensitive cells in the small intestinal mucosa from radionuclides located in the small intestinal wall or contents. METHODS: A model was developed for calculation of the self-dose and cross-dose from activity in the intestinal wall or contents. The small intestine was modeled as a cylinder with 2 different wall thicknesses and with an infinite length. Calculations were performed for various mucus thicknesses. S values were calculated using the EGS4 Monte Carlo simulation package with the PRESTA algorithm and the simulation results were integrated over the depth of the radiosensitive cells. The cross-organ dose was calculated by summing the dose contributions from other intestinal segments. Calculations of S values for self-dose and cross-dose were made for monoenergetic electrons, 0.050-10 MeV, and for the radionuclides (99m)Tc, (111)In, (131)I, (67)Ga, (90)Y, and (211)At. RESULTS: The self-dose S value from activity located in the small intestinal wall is considerably greater than the S values for self-dose from the contents and the cross-dose from wall and contents except for high electron energies. For all radionuclides investigated and for electrons 0.10-0.20 MeV and 8-10 MeV in energy, the cross-dose from activity in the contents is higher than the self-dose from the contents. The mucus thickness affects the S value when the activity is located in the contents. CONCLUSION: A dosimetric model for the small intestine was developed that takes into consideration the localization of the radiopharmaceutical in the intestinal wall or in the contents. It also calculates the contribution from self-dose and cross-dose. With this model, more accurate calculations of absorbed dose to radiation-sensitive cells in the intestine are possible.

Electrons↗
PubMed2001

Long-Term treatment with cisapride and antibiotics in liver cirrhosis: effect on small intestinal motility, bacterial overgrowth, and liver function.

OBJECTIVES: Altered small-bowel motility, lengthening of the orocecal transit time, and small-intestinal bacterial overgrowth have been described in patients with liver cirrhosis. These changes might be related to the progressive course and poor prognosis of the disease. We investigated the effect of a long-term treatment with cisapride and an antibiotic regimen on small-intestinal motor activity, orocecal transit time, bacterial overgrowth, and some parameters of liver function. METHODS: Thirty-four patients with liver cirrhosis of different etiology entered in the study. They were randomly allocated to receive cisapride (12), an alternating regimen of norfloxacin and neomycin (12), or placebo (10) during a period of 6 months. At entry and at 3 and 6 months, a stationary small-intestinal manometry was performed, and orocecal transit time and small-intestinal bacterial overgrowth were also investigated using the H2 breath test. Liver function was estimated with clinical and laboratory measurements (Child-Pugh score). RESULTS: After 6 months, both cisapride and antibiotics significantly improved fasting cyclic activity, reduced the duration of orocecal transit time, and decreased small-intestinal bacterial overgrowth. Cisapride administration was followed also by an increase in the amplitude of contractions. No statistically significant variations in these parameters were observed with placebo. An improvement of liver function was observed at 3 and 6 months with both cisapride and antibiotics. CONCLUSIONS: Long-term treatment with cisapride or antibiotics reversed altered small-intestinal motility and bacterial overgrowth in patients with liver cirrhosis. These findings suggest a possible role for prokinetics and antibiotics as a modality of treatment in selected cases of decompensated cirrhosis.

Adult↗
PubMed1994

Generation of neomucosa in vivo by transplantation of dissociated rat postnatal small intestinal epithelium.

A novel method to study the generation of rat small intestinal mucosa, by transplantation of disaggregated postnatal rat small intestinal epithelium is described. Cellular aggregates, comprised of epithelium with attached proliferative cells and closely associated stromal tissue, were isolated from postnatal rat small intestine by enzymatic digestion, then grafted immediately to the subcutaneous plane of adult recipients. On graft retrieval after 14 days, 39% of cellular transplants to nude mice, and 84% of cellular transplants to inbred rats had developed into small intestine-like structures. These structures were comprised of a circumferential layer of epithelium surrounding a central mucin filled lumen. This neomucosal layer exhibited well formed crypts and villi, and contained all epithelial stem cell lineages i.e. absorptive enterocytes, goblet cells, Paneth's cells and entero-endocrine cells. Proliferative activity within this neomucosa was confined to crypt regions as in normal postnatal small intestine. Developmental maturation within the regenerated neomucosa was demonstrated by organotypic morphogenesis, i.e. formation of mature crypts and villi, and progressive cytodifferentiation with increased numbers of goblet cells, entero-endocrine cells and Paneth's cells. Altered patterns of brush border enzyme expression further confirmed a temporal progression of development within neomucosal enterocytes. It is concluded that after "extensive" mucosal disaggregation, postnatal small intestinal epithelial progenitor cells retain the capacity for organotypic regeneration of neomucosa when transplanted to ectopic sites in adult recipients. These small aggregates of epithelium and stroma are capable of generating the topographical signals necessary for the three dimensional regeneration of this tissue. Furthermore, the multipotent generative potential of the stem cells within these cellular aggregates is maintained with production of all progeny.

Animals↗
PubMed1984

The mechanism of motilin excitation of the canine small intestine.

Close intraarterial injections of motilin to the small intestine of the anaesthetized dog produce prolonged phasic contractions. Tetrodotoxin infused intraarterially blocked field stimulated contractions and abolished the response to motilin as did treatment with a combination of hexamethonium and atropine. Atropine alone increased the dose of motilin required to induce responses. Hexamethonium alone similarly increased the dose of motilin required in the jejunum, but not for the ileum. These results suggest that motilin acts to contract small intestine by stimulation of intrinsic excitatory nerves, some of which are post-ganglionic cholinergic and some of which are not, but are activated by a pathway with a nicotinic synapse. The ED50 for ileal contractions was greater than that for the jejunum and the time to reach maximum contractions longer suggesting a decreased responsiveness of the lower small intestine to motilin as compared to the upper gastrointestinal tract. These results and the lesser quantity of immunoreactive motilin in the ileum than in the jejunum may explain the lack of relationship of the activity front of the migrating motor complex in the lower small intestine to venous motilin concentrations.

Animals↗
PubMedDate not supplied

[Integrative mechanisms of the formation of the small intestine motor effects].

Contractile responses of the small intestine to serotonine and histamine are mediated by cholinergic neurones, while the inhibitory responses of the substances--by nonadrenergic inhibitory neurones of the enterometasympathetic nervous system. An inhibitory response of the small intestine to met-enkephalin results from its depressing action on the effector cholinergic neurones. Catecholamines activate enteric cholinergic neurones via presynaptic beta-adrenoceptors and inhibit them via pre- and postsynaptic alpha-adrenoceptors. The cholinergic neurones of the enterometasympathetic nervous system seem to be under a double adrenergic control, and a mechanisms seems to exist in the small intestine for adrenergic activation of its contractile apparatus.

Acetylcholine↗
PubMed2004

Drug delivery to the small intestine.

Oral delivery of drugs to the small intestine is an important topic in the research and development of more effective oral dose forms. This review highlights several important developments in this area. An overriding theme in drug delivery to the small intestine is how to increase the efficiency (ie, how to increase bioavailability) of absorption. The role of P-glycoprotein and intestinal transporters is discussed in this regard. These systems are normally studied under defined in vitro conditions; recent data suggest that this approach, though useful, may not fully represent the in vivo situation. Recent advances and issues in the characterization and prediction of drug absorption from the small intestine are reviewed. These efforts, if successful, will shorten development timelines by eliminating compounds with poor absorption characteristics early in the process. Nanoparticulate delivery systems and those prepared by microfabrication technology are being used to improve bioavailability of poorly absorbed drugs. A relatively new technique (electroporation) has been proposed to enhance oral delivery of macromolecules, still an unrealized objective in drug delivery.

Administration, Oral↗
PubMed1984

Mesenteric hammock for retaining the small intestine after radical pelvic surgery.

The small bowel often partakes in complications seen after major colorectal and other pelvic operations. Trapped loops of small intestine within the pelvic basin may produce benign adhesive obstruction and are also exposed to recurrent malignancy. These problems may be compounded by the effects of radiotherapy. To reduce some of these complications, many methods have been devised to reconstruct the pelvic floor and thereby retain the small intestine within the abdominal cavity. Autogenous material such as omentum and peritoneal flaps have been employed as a substitute for the excised peritoneal pelvic lining. However, these methods may not be feasible in some reoperated patients, especially if prior irradiation has induced extensive peritoneal fibrosis, or if the omentum is absent or attenuated. We describe a technique in which the small-bowel mesentery is used as a hammock across the pelvic brim in order to support the small intestine out of the pelvic cavity. It has been used successfully in patients with complications after abdominoperineal resection for carcinoma of the rectum: one enterovaginal fistula associated with radiation injury and cancer, and three enteroperineal fistulas.

Humans↗
PubMed1990

Purification and biological properties of an epithelial intestinal cell growth inhibitor from a human small intestine.

Endogenous mitotic inhibitors act as control-mechanisms in intestinal epithelium proliferation. The presence of an inhibitor of cultured intestinal epithelial cell from a villous extract of rat jejunum has been reported in one of our papers. The object of the study now reported was to find the presence of a growth inhibitor in the villous extract from man's small intestine and to purify and characterize this factor when found. Our results reveal that: (1) Such an inhibitor was found in a supernatant preparation obtained from human intestinal epithelial cells. The inhibition of the proliferation of epithelial cells (IRD-98) it induced was seem to be dose-dependent and non-cytotoxic. (2) After chromatography on hydroxylapatite, on DEAE and then on ACA 54 (gel permeation), a low-molecular-weight protein (15 kDa) called purified intestinal inhibitor (PII) was isolated (purification factor of approx. 50,000 with respect to the supernatant fraction). This fraction proved to inhibit the IRD-98 cells in a reversible manner. When cells are incubated with this protein, cells prove to be arrested in phase G1 of the cell cycle as is revealed by the flow cytometry studies. The results obtained support the hypothesis that regulation of cell proliferation is mediated by endogenous inhibitors at the epithelial level.

Animals↗
PubMed2001

Usefulness of endoscopic small intestinal biopsies in children with coeliac disease.

Small intestinal biopsy is the most important diagnostic method in the routine evaluation of children with chronic diarrhoea and malabsorption. At present morphological alterations are considered essential in the diagnosis of coeliac disease (CD) and the presence of a normal small bowel biopsy specimen, observed in patients eating a diet containing gluten, rules out the diagnosis of CD. The small intestinal biopsy can be carried out either by blind suction capsule or by endoscopic forceps. In everyday clinical practice endoscopic duodenal biopsies, if taken and handled suitably, are accepted as equivalent to capsule biopsies from the proximal jejunum. In the study we reported some patients in whom has been possible to demonstrate the presence of total villous atrophy in one biopsy, while other duodenal samples taken in different duodenal portions were normal or showed mild lymphocytes and plasmacells infiltrations of the lamina propria. In patients with this type of biopsy pathology, wherein flat mucosa has been found even close to normal mucosa, the possible explanation is mucosal patchiness. The occurrence of patchly distributed intestinal atrophy in children suffering of CD raises the question of the validity of using the peroral capsule, widely believed to be the best standard for the diagnosis of CD. In our opinion, small intestinal biopsies obtained via endoscopy are more reliable than the peroral capsule biopsies in order to identify patchy mucosal atrophy and could be very useful for a correct diagnosis in CD patients.

Adolescent↗
PubMed1995

Evidence for the regulation of small intestinal Na+/glucose cotransporter by insulin.

The small intestinal sodium dependent absorption of D-glucose has been known to be increased by diabetes mellitus. Furthermore, we previously showed that the enhanced activity of Na+/glucose cotransporter (SGLT1) was restored by the treatment with insulin. The present study was designed to investigate the mechanism by which diabetes mellitus and insulin regulated the activity of the small intestinal SGLT1. The acute diabetes at 2 weeks after the injection of streptozotocin increased the expression of SGLT1 protein in rat small intestinal brush border membrane vesicles without changing the mRNA level for SGLT1. In addition, we showed that the increased content of SGLT1 protein was restored by the subcutaneous treatment with insulin. In contrast, there was no change of the mRNA level for SGLT1 in diabetic and insulin-treated diabetic rats. These results suggest that rat intestinal SGLT1 activity is under the translational or posttranslational controls by insulin.

Animals↗