Colonic transit scintigraphy labeled activated charcoal compared with ion exchange pellets

Scintigraphic measurement of colonic transit is currently performed by delivering 111In ion exchange resin pellets to the colon in a methacrylate-coated capsule. However, use of this method is constrained by the need for an investigational drug permit. We have demonstrated previously optimal adsorption in vitro of commonly used radioisotopes (e.g., 99mTc or 111In) to activated charcoal in milieus that mimicked gastric and small intestinal content. The aim of this study was to compare the transit profiles of radioactive activated charcoal and resin pellets delivered to the colon in the same methacrylate-coated capsule. METHODS: In 10 healthy volunteers, we compared the colonic transit profiles over 32 hr of simultaneously administered resin pellets labeled with 111In and activated charcoal mixed with 99mTc-diethylenetriaminepentaacetic acid. Transit was summarized as the geometric center (weighted average of counts) in the colon at each scanning period. RESULTS: Colonic transit profiles were virtually identical with the two markers, with less than 0.1 geometric center unit differences in the transit profiles over the 32-hr periods. CONCLUSION: Activated charcoal is a suitable alternative to resin pellets when delivered in a methacrylate-coated, delayed-release capsule to the colon for measurement of transit by scintigraphy.     

Excretion of endogenous and exogenous purine derivatives in sheep: effect of increased concentrate intake

The scintigraphic measurement of colonic transit is currently performed using 111In ion exchange resin pellets delivered to the colon in a capsule coated with a pH sensitive polymer, methacrylate, which dissolves in the distal ileum. However, in the USA, this requires an investigational drug permit. Our aim was to evaluate the in vitro binding characteristics of activated charcoal in milieus that mimicked gastric and small intestinal content. The in vitro incubation of activated charcoal was performed with Na99Tc(m)O4, 99Tc(m)-DTPA, 111InCl3, 111In-DTPA, 201TlCl and 67Ga-citrate in the pH range 2-4 and pH 7.2 at 37 degrees C. We estimated the association of radiopharmaceuticals with the activated charcoal over a 3 h in vitro incubation. With the exception of 67Ga-citrate, the association of activated charcoal with the other radiopharmaceuticals was approximately 100% throughout the 3 h incubation. In conclusion, activated charcoal appears to adsorb avidly with common radioisotopes, and appears promising as an alternative to resin ion exchange pellets used for the measurement of gastrointestinal transit by scintigraphy.     

ECG-gated dual-isotope myocardial SPECT with 201Tl and 99mTc-tetrofosmin: simultaneous assessment of stress/rest myocardial perfusion and left ventricular function

ECG-gated dual-isotope acquisition protocol involving rest imaging with 201Tl and stress 99mTc-tetrofosmin (TF) SPECT was designed for the simultaneous assessment of rest/stress myocardial perfusion and rest ventricular systolic function. This study assessed the feasibility and diagnostic accuracy of this protocol. Forty-five patients underwent the dual-isotope SPECT protocol. Twenty minutes after resting injection of 111 MBq of 201Tl, 370 MBq of 99mTc-TF was administered at a peak exercise. The dual-isotope gated SPECT acquisition was performed 1 hour later. Then, the regional count increase rate (%WT) of 99mTc-TF from end-diastole end-systole was calculated using an automated method which was developed for quantification of regional wall thickening based on circumferential profile analysis in our laboratory. Myocardial perfusion and contractility analysis was carried out using 8 segments of left ventricle with comparison of coronary angiographical findings. The sensitivity and specificity for the detection of diseased coronary vessels (> = or 75% stenosis) were 76% and 94%, respectively. Infarcted regions showing reversible defect had significantly greater %WT as compared with those with fixed defects (63 seg; 12.7 +/- 6.1% vs. 36 seg; 8.9 +/- 7.2%, p < 0.01). In conclusion, this dual-isotope protocol has some advantages; i.e., shortening an examination time, having the exact registration of stress/rest perfusion, and simultaneous evaluation of resting regional wall thickening.     

Demethylation of the progesterone receptor CpG island is not required for progesterone receptor gene expression

In a previous study we have shown that an intravenous infusion of pramlintide (an analogue of human amylin) delayed gastric emptying, but the dose of pramlintide was supraphysiological in relation to the amylin response to food in non-diabetic subjects. The purpose of this study was to examine the dose response relationship of subcutaneous injections of pramlintide on gastric emptying and to determine whether administration of the drug before one meal has an impact on the subsequent meal. Eleven men with insulin-dependent diabetes mellitus were studied in a double-blind, randomised, four-way crossover design. None had autonomic neuropathy. Euglycaemia was maintained overnight before the study day. At -30 min the patients self-injected their usual morning insulin and at -15 min they injected the study drug (either placebo or 30, 60 or 90 microg pramlintide) subcutaneously. At 0 min they ate a standard meal consisting of a pancake, labelled with 99mTc, and a milkshake containing 3-ortho-methylglucose (3-OMG). Gastric emptying images were obtained for the next 8 h. At 240 min the subjects ate a similar meal, but on this occasion the pancake was labelled with (111)In. All three doses of pramlintide delayed emptying of the solid component of the first meal (p < 0.004) with no significant difference between the drug doses. There were no differences between placebo and pramlintide after the second meal. All three doses of pramlintide resulted in a prolongation in the time to peak plasma 3-OMG level (p < 0.0001) after the first meal but there was no difference after the second meal.     

Abnormal progression of a liquid meal through the stomach and small intestine in patients with Chagas' disease

This study describes the abnormal pattern of gastrointestinal progression of a liquid meal in patients with the digestive form of chronic Chagas' disease. This condition is known as a natural model of intramural denervation of the gut. Sixteen patients with clinical and radiographic evidence of esophageal and/or colonic involvement and 18 healthy volunteers were studied. Orocecal transit time after the ingestion of a 10% lactulose solution (180 ml) tagged with 99mtechnetium was measured by a conventional H2 breath technique. Gastric emptying and the arrival of the front of the meal to regions of interest corresponding to proximal and distal areas of the small intestine were assessed by abdominal scintigraphy. Orocecal transit time was significantly greater (P < 0.05) in Chagas' disease patients (N = 13) than in control subjects (N = 18) (mean +/- SD: 100.7 +/- 48.7 min vs 62.9 +/- 18.2 min). Half-time for gastric emptying of liquids in chagasic patients (N = 9) was significantly lower (P < 0.01) than in controls (N = 7) (9.7 +/- 2.7 min vs 26.4 +/- 3.4 min). The time of arrival of the liquid meal to the proximal small intestine was also significantly shorter (P < 0.02) in patients than in controls (5.6 +/- 3.7 vs 11.4 +/- 5.5 min), but there was no difference between the two groups concerning the time the meal first arrived to the distal small intestine (15.0 +/- 11.0 min vs 23.5 +/- 11.4 min, P > 0.05). These results indicate that patients with Chagas' disease have a combination of exceedingly rapid gastric emptying and abnormally delayed transit of liquids through the more distal segments of the small bowel.(ABSTRACT TRUNCATED AT 250 WORDS)     

Comparative effects of enteric-coated pancreatin microsphere therapy after conventional and pylorus-preserving pancreatoduodenectomy

BACKGROUND: A comparative study was performed between patients with exocrine pancreatic insufficiency after conventional pancreatoduodenectomy (Whipple's procedure) and pylorus-preserving pancreatoduodenectomy (PPPD). In these patients the pharmacodynamics of 2-mm enteric-coated pancreatin microspheres (ECPMs) and their gastric transit time in relation to that of a solid meal were investigated. The efficacy of ECPM preparations may differ after Whipple's procedure compared with PPPD, because the latter procedure does not include gastrectomy. METHODS: Gastric transit was assessed by double-isotope scintigraphy. A pancake meal was labelled with 99mTc. ECPMs were cold-labelled with 170Er and neutron activated shortly before ingestion to enable imaging with a gamma camera. Intraluminal pancreatic enzyme activity was assessed during a 6-h period with two indirect tests: the cholesteryl [14C]octanoate breath test and the N-benzoyl-L-tyrosyl-p-aminobenzoic acid-p-aminosalicylic acid (NBT-PABA-PAS) test. RESULTS: In patients who had Whipple's procedure, the gastric transit time of ECPMs and of the pancake meal was not significantly different. The outcome of the indirect pancreatic function tests during enzyme supplementation was comparable, and not significantly different, from that in healthy volunteers. In patients who had PPPD, however, the gastric transit time of microspheres was greatly delayed compared with that of the pancake meal (P < 0.05). Improvement in the outcome of the indirect pancreatic function tests during enzyme supplementation was much less and remained well below that of healthy volunteers (P < 0.05). CONCLUSION: In cases of exocrine pancreatic insufficiency after Whipple's procedure, 2-mm ECPM treatment adequately restores pancreatic enzyme activity. Following PPPD, however, ECPM treatment is often ineffective because the microspheres are retained in the stomach. In these patients, use of conventional powdered pancreatin enzyme preparations may improve the efficacy of treatment.     

Quantitative autoradiography using a radioimager based on a multiwire proportional chamber

Determination of the biodistribution of radiopharmaceuticals is an important issue for the evaluation of their performance in diagnosis and therapy. In this study, we evaluated a digital radioimager (RI) based on a multiwire proportional chamber for quantitative autoradiography (AR). The RI allows direct detection of electronic emissions of gamma emitters. Its qualitative and quantitative performances were tested on 99mTc and (111)In labelled sections and compared with conventional film AR. Linearity of count rate versus activity was verified over a 104 range of activity. As compared with film AR, a substantial improvement of the detection limit was obtained even for acquisition periods up to 20 times less than film exposure times. We provided the basis for quantitative analysis with tissue equivalent paste standards: the 99mTc and (111)In RI counting efficiencies were respectively 1.19% and 2.35%. We illustrated the respective values of RI and film AR in two rat studies: 99mTc-DMSA in kidney and dual-isotope 99mTc-MIBI and (111)In-antimyosin in heart. Calculated activity concentrations on sections of rat organs confirmed good correlation to gamma counting (deviation less than 12%). We suggest RI as a convenient technique for fast localization of single or dual-isotope tracers and determination of activity distribution.     

Gastrointestinal transit in patients with idiopathic megarectum

PURPOSE: In patients with idiopathic megarectum, it is unknown whether abnormality is limited to the dilated large bowel or whether the upper gut is abnormal, as in the various forms of chronic intestinal pseudo-obstruction. This has important implications for treatment, especially surgery. METHODS: Ten patients (4 females; median age, 18 (range, 17-26) years) with idiopathic megarectum had contrast studies of the upper and lower gut, radioisotope (technetium-99m liquid and indium-111 solid phase) measurement of gastric, small-bowel, and colonic regional transit, and radiopaque marker colonic studies. RESULTS: All patients had a dilated large bowel. No patient had radiographic evidence of upper gut dilation. Four patients had normal and six patients had abnormally slow gastric emptying. Both the radioisotope scans and radiopaque marker studies showed abnormal colonic transit. Regions of delay corresponded with the region of dilated bowel. Symptoms of abdominal distention and bloating did not correspond to abnormalities of gastric emptying but rather with effectiveness of rectal evacuation. CONCLUSION: Patients with idiopathic megarectum have abnormal colonic transit, delay occurring predominantly in the dilated gut. Marker studies are less sensitive than isotope studies but provide adequate information for clinical purposes. Although motility abnormalities of the upper gut are common, symptoms correlate with large-bowel abnormalities.     

Rapid distal small bowel transit associated with sympathetic denervation in type I diabetes mellitus

BACKGROUND: The pattern of progression of a meal from the stomach to the caecum in diabetes mellitus is controversial and the differential roles of transit through the jejunum and the ileum have not been investigated in diabetes. AIMS: To determine gastric emptying and transit rates through proximal and distal regions of the small bowel in type I diabetic patients. SUBJECTS: The study included six diabetic patients with evidence of autonomic neuropathy (DM-AN group), 11 diabetics without autonomic dysfunction (DM group), and 15 control volunteers. METHODS: Gastric emptying and small bowel transit of a liquid meal were evaluated scintigraphically in these subjects. Transit through regions of interest corresponding to the proximal and distal small intestine up to the caecum was determined and correlated with gastric emptying rates, cardiovascular measurements of autonomic function, and the occurrence of diarrhoea. RESULTS: Gastric emptying and transit through the proximal small bowel were similar in the three groups. The meal arrived to the caecum significantly earlier in DM-AN patients (median; range: 55 min; 22-->180 min) than in the DM group (100 min; 44-->180 min, p < 0.05) or in controls (120 min; 80-->180 min, p < 0.02). Accumulation of chyme in the distal small bowel was decreased in DM-AN patients, who showed values for peak activity (30%; 10-55%) significantly lower than in the DM group (49%; 25-77%, p = 0.02) and controls (50%; 30-81%, p = 0.02). In DM patients (n = 17), the time of meal arrival to the caecum was significantly correlated with both orthostatic hypotension (coefficient of contingency, C = 0.53, p < 0.01) and diarrhoea (C = 0.47, p < 0.05), but not with gastric emptying rates. CONCLUSIONS: Patients with type I diabetes mellitus and sympathetic denervation have abnormally rapid transit of a liquid meal through the distal small bowel, which may play a part in diarrhoea production.     

Study of gastric emptying by dual isotopes. Corrections due to contamination

The evaluation of gastric emptying by the double isotope technique involves some methodologic conditioning. Among them contamination correction or interference in the energy windows of the activity of the two isotopes used in the marking of the solids and fluids of the test food are important. The results of an experiment in which a phantom was used to evaluate the contamination between indio 111 (DTPA-Ca111In) and technecium 99m (colloid99mTc). Three test studies were posteriorly performed in healthy volunteers and 27 studies in a control group (13 males, mean age of 33 years, mean body mass index 39.02 kg/m). In these studies the contamination was corrected with the acquisition, following an initial swallow of juice marked with 111In, of activity in the windows of both isotopes. The contamination of 111In (isotope of greatest radiation energy) in the window of 99mTc was 24% in the phantom and 20%, 23% and 26% in the three initial study tests. The mean contamination in the control group was of 22% with limits of 19% to 29% and a standard deviation of 3%. Despite the comparable results, the usefulness of the individualized contamination calculation in the studies of gastric emptying with dual isotope to minimize the methodologic errors of this technique is discussed.     

Aberrant methylation of p16INK4a and deletion of p15INK4b are frequent events in human esophageal cancer in Linxian, China

Esophageal transit scintigraphy seems to be a valid methodology to assess impaired esophageal motility in early stages of disease. The purpose of this study was to discriminate patients with primary Raynaud's phenomenon (RP) and patients with systemic sclerosis (SSc) from healthy subjects by esophageal scintigraphy with a semisolid meal. METHODS: We studied 32 patients with primary RP, 18 with SSc and 13 healthy subjects. Dysphagia, acid regurgitation and heartburn were scored. After an overnight fast, all subjects underwent esophageal scintigraphy, using a semisolid orally ingested bolus (10 mL apple puree) labeled with 99mTc-sulfur colloid. Esophageal transit and emptying time and integral value were evaluated with the subjects in the upright (sitting) and supine positions. Transit time was defined as the time from the entry of 50% of radioactivity into the upper esophagus until the clearance of 50% of the bolus from the whole esophagus. Emptying time was defined as the time from the entry of 50% of radioactivity into the upper esophagus, until the clearance of 100% of the bolus from the whole esophagus. Integral value was defined as the total counts under the time-activity curve normalized to the maximum. RESULTS: Esophageal transit and emptying time and integral value, evaluated in both positions, were significantly higher in patients with SSc than in healthy subjects and than in patients with RP. Moreover, patients with RP had all three parameters, assessed in supine position, significantly longer compared to healthy subjects. Clinical scores regarding dysphagia, acid regurgitation and heartburn were not significantly different between patients with RP and SSc. CONCLUSION: Esophageal transit and emptying time and integral value appear to be able to discriminate patients with primary RP from patients with SSc and patients with RP from healthy subjects, suggesting an early mild esophageal dysfunction in RP.     

Complex formation of the nonstructural protein 3 of hepatitis C virus with the p53 tumor suppressor

BACKGROUND: Length of survival of females with cystic fibrosis is worse than it is in males. Results of current research have shown an important correlation among dietary intake, nutritional status, lung function, and survival. The purpose of this study was to explore gender differences in dietary intake and pancreatic enzyme replacement therapy in males and females with cystic fibrosis. METHODS: The study was a cross-sectional measurement of clinical characteristics, energy, and fat intakes in males and females attending the cystic fibrosis outpatients clinics of the John Hunter Hospital, Newcastle, Australia. Twenty-nine subjects, (17 females and 12 males), completed 4-day weighed food records to measure total energy intake and the contribution of macronutrients and to document use of pancreatic enzyme replacement therapy. Energy intake was assessed as the percentage of the recommended energy intake for age and sex. RESULTS: Females with cystic fibrosis had significantly lower energy and fat intakes than males, whereas the females used significantly more pancreatic enzyme replacement therapy. There were no significant differences in clinical characteristics between groups. CONCLUSION: The results support the possibility that gender differences in the energy and fat intakes of older patients may contribute to differential median survival time of males and females with cystic fibrosis.     

Effect of capsaicin-containing red pepper sauce suspension on upper gastrointestinal motility in healthy volunteers

Afferent nerves play a major role in the regulation of gastrointestinal motility. The questions remains if specific food ingredients can selectively activate such fibers. The aim of the study was to investigate the effect of intraesophageal application of a capsaicin-containing red pepper sauce (Tabasco) suspension on upper gastrointestinal motility in a controlled trial. After a baseline recording [esophageal motility, balloon distension, electrogastrogram (EGG)], red pepper or saline solution was infused intraesophageally in seven healthy volunteers. At 30 min gastric emptying and orocecal transit time were determined using a [13C]acetate and H2-lactulose breath test. Infusion of red pepper sauce suspension significantly increased the amplitudes (65.8 +/- 3 to 78.5 +/- 4.7 mm Hg, P < 0.05) and propagation velocity (2.9 +/- 0.3 to 4.25 +/- 0.3 sec, P < 0.05) of esophageal pressure waves and LES pressure (17.8 +/- 1.4 to 23.7 +/- 2.6 mm Hg, P < 0.05). It significantly decreased perception and discomfort threshold of intraesophageal balloon distension, reduced the percentage of normal electrical activity in the EGG, and delayed gastric emptying (saline: T(1/2) 42.9 +/- 12.0 min vs red pepper: T(1/2) 66.8 +/- 19.0 min, P < 0.05). Despite the prolongation of gastric emptying, orocecal transit time was not altered, indicating an actual increase of intestinal transit. Esophageal application of capsaicin-containing red pepper sauce suspension had profound changes on upper gastrointestinal motility, which could improve clearance and protection of the esophagus and could lead to retention of the irritant in the stomach and faster transit through the small bowel.     

PEDB: the Prostate Expression Database

Naloxone is generally considered to be a pure antagonist, but it may produce several behavioral effects, such as hyperalgesia or stimulation of respiration. We studied the effect of naloxone on gastric emptying and gastrointestinal transit in rats. Six to eight Wistar rats (200-250 g) were used for each experiment. Either saline or naloxone (0.01-10 mg/kg) was injected intraperitoneally at 0 min. At 30 min, radiolabeled saline or milk 1 mL was infused into the stomach. At 60 min, gastric emptying and gastrointestinal transit were calculated by measuring the radioactivity in the gastrointestinal tract. Naloxone significantly inhibited gastric emptying of saline (P = 0.002) and of milk (P < 0.05), but not the gastrointestinal transit of either (P > 0.05). Gastric emptying of saline showed a significant peak (P < 0.05) in the dose-response curve at 0.7 mg/kg. Therefore, naloxone significantly inhibits gastric emptying of saline and milk, but not the gastrointestinal transit of either. IMPLICATIONS: Although naloxone is generally considered to be a pure opioid receptor antagonist, it delays gastric emptying of saline or milk, as does morphine in the rat. However, it is uncertain from our results whether naloxone inhibited gastric emptying by antagonizing the effects of endogenous opioids.     

Does Helicobacter pylori infection affect gastric emptying in patients with functional dyspepsia?

The objectives of the study were first, to determine if gastric emptying was altered in patients with functional dyspepsia with and without Helicobacter pylori infection compared with normal healthy volunteers; and second, to determine if there were further alterations in gastric emptying when the infection was eradicated. Gastric emptying was measured using a 99mtechnetium radiolabelled solid meal and gastric emptying time was measured as t1/2, viz. time taken for half the radiolabelled meal to be emptied from the stomach. The mean gastric emptying time for H. pylori-positive patients (n=20) was 56.4+/-24.8 min; H. pylori-negative patients (n=19) 67.8+/-31.8 min; and normal controls (n=20) 58.8+/-18.8min. No significant difference was obtained between the groups (ANOVA; P=0.348). Thirteen of 18 H. pylori-positive patients successfully eradicated the infection following treatment with omeprazole 40 mg o.m. and amoxycillin 500 mg t.d.s. for 2 weeks. The mean difference in the gastric emptying time before and after H. pylori eradication was 23.9+/-13.2 min (P= 0.556). There was no significant difference in the frequency of specific dyspeptic symptoms as well as the overall mean symptom score between the H. pylori-positive and -negative patients. Gastric emptying was not different between patients with functional dyspepsia and normal controls. Helicobacter pylori infection does not appear to affect gastric emptying in patients with functional dyspepsia.     

Glucagon-like peptide-1 retards gastric emptying and small bowel transit in the rat: effect mediated through central or enteric nervous mechanisms

This study investigated effects of glucagon-like peptide-1(7-36)amide (GLP-1) on gastric emptying, small intestinal transit, and contractility of smooth muscle strips in rats. GLP-1 at doses of 10 and 20 pmol/kg/min administered intravenously dose-dependently retarded transit of the small intestine (P < 0.001), while only the higher dose of 20 pmol/kg/min retarded gastric emptying (P < 0.01). GLP-1 at concentrations up to 10(-4) M did not affect the basal tone or contractility of the gastrointestinal muscle strips that were stimulated with electric field stimulation or acetylcholine. Our results demonstrate that small intestinal transit seems more sensitive than gastric emptying to inhibition by GLP-1 at physiologic levels in plasma. Furthermore, this inhibition appears to be mediated through central mechanisms rather than through peripheral actions. Thus, GLP-1 is suggested to inhibit gastric emptying and small intestinal transit through an indirect effect via central or enteric nervous mechanisms.     

The effect of octreotide on gastric emptying at a dosage used to prevent complications after pancreatic surgery: a randomised, placebo controlled study in volunteers

BACKGROUND: Octreotide is used in many centres to prevent complications after pancreatic surgery. Delayed gastric emptying is a another complication occurring in around 30% of patients after pancreatoduodenectomy (PD) and causes prolonged hospital stay. The influence of octreotide on this complication is doubtful. AIMS: To assess the effect of octreotide, at the clinical dosage used after pancreatic surgery, on gastric emptying in healthy volunteers. SUBJECTS AND METHODS: Eight healthy male volunteers (mean age 22.5 years) participated in this double blind, placebo controlled study. On day 1 subjects received 100 micrograms of octreotide or placebo subcutaneously, three times daily and on day 2, one hour after the fourth injection, gastric emptying, postprandial cholecystokinin (CCK) release, and mouth to caecum transit time (MCTT) were measured. This protocol was repeated after one week, in a crossover design. On the test day subjects received a liquid test meal (1.57 MJ/300 ml) and gastric emptying measurements were performed with applied potential tomography, an non-invasive, validated technique which measures gastric emptying through impedance differences. From the gastric emptying curves, lag time, t50, and postlag emptying rate were measured. MCTT was measured using the hydrogen breath test. RESULTS: Lag time decreased from 29.6 (6.3) (mean (SEM)) to 12.2 (4.6) minutes (p < 0.05) during octretide treatment; t50 decreased from 87.8 (12.0) to 47.5 (8.2) minutes (p < 0.02) and there was a trend towards an increased postlag emptying rate (0.8 to 1.6% per minute; p = 0.07). MCTT increased from 150 (12.7) to 229 (17.9) minutes during octreotide treatment (p < 0.01). Octreotide suppressed postprandial CCK release (p < 0.05). CONCLUSIONS: MCTT was delayed by octreotide, suggesting impairment of small bowl treatment. Octreotide administered at the clinical dosage for pancreatic surgery accelerates gastric emptying, mainly by shortening the lag time. Suppression of postprandial CCK release may be involved in this process. Octreotide administration is therefore not a contributing factor in the pathogenesis of delayed postoperative gastric emptying after PD and might even play a role in preventing this complication.     

Accelerated right colonic emptying after simulated upper gut hemorrhage

OBJECTIVE: Upper gastrointestinal hemorrhage delays gastric emptying. Our aim was to evaluate the effect of gastrointestinal hemorrhage on small intestinal, ileocecal, and proximal colonic transit. METHODS: Healthy volunteers were randomized to receive either a duodenal infusion of heparinized autologous blood (n = 7) or egg white, acting as a control substance with similar composition; 1.5 mCi99mTc-DTPA was added to the infused substances. We infused 30 ml at an infusion rate of 1 ml/min. Gamma-camera images were taken for 4 h or until all radioactivity had entered the colon. Arrival of radiolabels in the colon and also counts in the ascending and transverse colon were quantified. RESULTS: Small intestinal and ileocecal transit were not significantly different between blood and egg white infusions. However, ascending colonic emptying was significantly faster after blood infusion compared to egg white. Four hours after the start of blood infusion a median of 30% of counts were in the transverse colon (11-50%; 25th-75th percentile) versus 0% (0-7%) after egg white infusion (p < 0.001). CONCLUSION: We concluded that simulated upper gastrointestinal bleeding hastens proximal colonic transit, but does not alter small intestinal transit and colonic filling.     

Dysfunctional voiding in women: which muscles are responsible?

We studied the effect of mixed agonist-antagonist opioids (nalbuphine and pentazocine) and a kappa opioid agonist (U50488H) on gastric emptying and gastrointestinal transit, and their interactions with morphine in rats. In each group, nalbuphine (0.01-30 mg kg-1), pentazocine (1-30 mg kg-1), U50488H (1-100 mg kg(-1)1) or saline was injected i.p. at 0 min. Another four groups of rats received morphine 13.4 mg kg-1 (ED75) and one of the following substances: saline, nalbuphine, pentazocine or U50488H. In both groups, at 30 min, radiolabelled saline 1 ml was infused into the stomach; at 1 h, gastric emptying and gastrointestinal transit were calculated by measuring the radioactivity in the gastrointestinal tract. Slopes for dose-response curves were determined. Nalbuphine significantly, but only weakly, delayed gastric emptying (P < 0.0005) and gastrointestinal transit (P < 0.01). Pentazocine markedly inhibited both, whereas U50488H did not significantly inhibit either. The slopes of the dose-response curves for nalbuphine, but not for pentazocine, on both gastric emptying and gastrointestinal transit were significantly less steep than those for morphine. Nalbuphine significantly antagonized the inhibitory effect of morphine on gastric emptying (P = 0.005) and gastrointestinal transit (P = 0.02), whereas pentazocine and U50488H did not. Nalbuphine and pentazocine delay gastric emptying and gastrointestinal transit, possibly by different mechanisms.     

Gastric emptying and lingual lipase activity in cystic fibrosis

To identify gastric factors likely to contribute to fat maldigestion and malabsorption in cystic fibrosis (CF), gastric emptying time, secretion rate, and preduodenal lipolytic activity were studied. Gastric emptying of a liquid test meal and gastric acid secretion were determined in five CF teenagers with pancreatic insufficiency and in five healthy controls. During the first hr, the rate of gastric emptying exhibited a linear pattern in both CF patients and controls. Neither the emptying time nor the gastric secretion rate was different. Lingual lipase activity was measured in eight other CF patients with pancreatic insufficiency and in eight controls. Lipase activity was higher (P less than 0.05) in CF patients than in controls with values (mean +/- S.E.) of 34.48 +/- 11.59 and 12.65 +/- 5.60 mumole butyric acid min-1 ml-1, respectively. No correlation with age or body surface was observed. Intragastric lipolysis of a butterfat triglyceride test meal was fast in both groups, but more extensive (P less than 0.05) in CF patients than in controls. The data show that in CF with pancreatic insufficiency, gastric factors contributing to the first step of fat digestion are preserved. In fact, lingual lipase activity was found to be increased, and a more complete intragastric lipolysis was documented.