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Biomedical subjects

R Jian

Publications and source records attributed to R Jian.

At least 55 records · Page 3Linked to original sources
PubMed1994

Effect of the energy density of a solid-liquid meal on gastric emptying and satiety.

The effect of the energy density of a meal on gastric emptying and satiety was assessed in nine volunteers. They ingested, in randomized order, a diluted (2671 kJ/L, 950 mL) and a concentrated (7452 kJ/L, 350 mL) test meal of 2500 kJ each (80% as solids). Half-emptying times of solids and liquids were not significantly different for the diluted and concentrated meal (solids: 145 +/- 18 and 156 +/- 16 min, respectively; liquids: 76 +/- 10 and 84 +/- 10 min, respectively), and consequently, pyloric outputs of energy were identical. Neither the intensity and duration of satiety, nor the amount of energy ingested, ad libitum, 6 h after the test meal, were significantly affected by energy density of the food ingested. Both the intensity and duration of satiety correlated significantly with the gastric emptying time for solids (r = 0.60 and 0.67, respectively, P < 0.01). These results show that satiety depends on gastric emptying of energy and is not affected by the energy density of food intake.

Adolescent↗
PubMed1994

Ileal tone in humans: effects of locoregional distensions and eating.

Using an electronic barostat in the human terminal ileum, we studied ileal tone in response to various stimuli in 10 healthy volunteers. Phasic activity was also measured by manometry. Graded orad (ileal) and caudad (cecal) balloon distensions did not produce any significant changes in ileal tone at all levels tested, even when a sensation of discomfort was felt. A linear relationship between pressure and volume was observed during in situ isobaric ileal distensions. Meal induced a biphasic tonic response with a brief (20 min) and immediate decrease in intrabag volume (64 +/- 7% of preprandial value, P < 0.05), followed by a prolonged increase in intrabag volume (158 +/- 10% of preprandial value, P < 0.05). A significant correlation was found between volume variations and phasic activities during the first phase (r = 0.88, P < 0.05), whereas no correlation was found during the second phase (r = 0.55, NS). The administration of glucagon induced a significant increase in intrabag volume from 45 +/- 5 to 70 +/- 8 ml (P < 0.05). We conclude that 1) regional distensions do not influence ileal tone and phasic motility, 2) the ileum does not show accommodation to distensions, and 3) meal produces an immediate increase in phasic and tonic activity followed by a prolonged relaxation.

Adult↗
PubMed1994

[Measurement of ileal absorption of bile salts with the selenium 75 labelled homotaurocholic acid test. Validation and clinical significance].

OBJECTIVES AND METHODS: The performances and the clinical significance of a simplified version of the 75SeHCAT test which measures ileal absorption of bile salts were assessed in 23 healthy subjects and 106 patients. Corporeal retention of the marker was measured using an uncollimated gamma-camera. RESULTS: In healthy subjects, the 75SeHCAT retention was lower in the group of 9 with an osmotic diarrhoea induced by a PEG solution than in the group of 14 tested in normal conditions (22 +/- 4% vs 44 +/- 4%; P < 0.01). The reproducibility of the measure was good (r = 0.93; P < 0.001). The sensibility and specificity of the test for the diagnosis of ileal involvement were 79% and 90% respectively. Bile acid malabsorption was evidenced in 38% of patients with functional diarrhoea (59% and 28% in patients with and without previous cholecystectomy respectively; P < 0.02). In patients with fonctional diarrhoea, a correlation was evidenced between the orofaecal transit time and the 75SeHCAT retention (r = 0.66; P < 0.001) and cholestyramine improved diarrhoea in 8 out of 11 patients with 75SeHCAT malabsorption and in 2 out of 5 patients with normal test. These results show that the 75SeHCAT test is accurate and that bile acid malabsorption, frequently evidenced in functional diarrhoea, is correlated with an acceleration of intestinal transit.

Adult↗
PubMed1992

[Disorders of gastric emptying].

Disorders of gastric emptying are observed in many clinical situations. Their symptoms are diverse and correlate poorly with the objective abnormalities of gastric emptying. The underlying mechanism consists of abnormalities of basal electrical rhythm, fundic compliance, post-prandial antral motricity and, above all, antro-pyloro-duodenal co-ordination, associated to varying degrees. Among possible causes 3 clinical situations predominate: diabetes mellitus, functional gastrointestinal disorders (idiopathic dyspepsia) and sequelae of gastric surgery where retention of solids and accelerated evacuation of liquids may coexist in the same patient. Treatment of gastric incontinence rests, almost exclusively, on dietary measures, but several drugs, such as metoclopramide, domperidone and cisapride, are available to treat gastric stasis. Other compounds, notably motilin agonists (erythromycin and its derivatives) are currently being evaluated and will reinforce this therapeutic armentarium in a not too distant future.

Cisapride↗
PubMed1992

Right and left colonic transit after eating assessed by a dual isotopic technique in healthy humans.

Propulsion of colonic contents after eating in the whole colon was studied in 15 volunteers by scintigraphy with injection of 111In-diethylenetriamine-pentaacetic acid and 99mTc-sulfur colloid into the colon through a nasogastric tube. The radionuclide was injected into the cecoascending colon (n = 7), the hepatic flexure (n = 6), the splenic flexure (n = 9), and the descending colon (n = 4). Changes of activity in the regions distal from and proximal to the injection points were determined before and after a 1000-kcal meal. Isotopic movements were also analyzed when a simultaneous injection of the two markers in the right and left parts of the colon was achieved (n = 11). During fasting, no significant change of activity was seen. After eating, radioactivity injected into the cecoascending and the hepatic flexure was transferred distally (P less than 0.01 and P = 0.07); radioactivity injected into the splenic flexure was transferred both distally (P = 0.07) and proximally (P less than 0.02); and no significant change of activity was seen proximally from or distally to the descending colon. Both antegrade and retrograde isotopic movements increased after eating (P less than 0.01), but the number of antegrade movements was significantly greater (P less than 0.05). This study confirms the colonic propulsive effect of eating and shows that this response is different in the right and left parts of the colon.

Adult↗
PubMed1992

Clinical relevance of scintigraphic measurement of gastric emptying of a solid-liquid meal in the dumping syndrome.

Gastric emptying of the solid and liquid components of an ordinary meal was evaluated by a dual isotopic technique in 36 patients referred to our hospital for early postprandial symptoms induced by various esophageal and/or gastric operations. Patients were classified as typical (n = 11), equivocal (n = 9) or improbable (n = 16) dumpers, in accordance with their presenting symptoms, as assessed before gastric emptying measurement. Patients with typical dumping symptoms displayed, as expected, significant acceleration of gastric emptying of liquids (t1/2: 18 +/- 6 min. vs. 48 +/- 7 min. in healthy controls; p less than 0.02), and also exhibited a dramatic enhancement of gastric emptying of solids (t1/2: 11 +/- 1 min. vs. 126 +/- 12 min. in healthy controls; p less than 0.001) and a complete loss of solid-liquid discrimination (7 +/- 6 min. vs. 78 +/- 7 min. in healthy controls; p less than 0.01). Mean gastric emptying rates for equivocal and improbable dumpers were not significantly different from those of healthy controls, but individual results were very heterogeneous; they included stasis, acceleration, or both disorders, and were not predictable by analysis of symptoms alone. Thus gastric emptying of solids as well as liquids is accelerated in symptomatic dumping patients, and objective evaluation of the emptying of both solid and liquid gastric emptying is essential in atypical dumpers, in order to characterize their disorders and prescribe the most rational treatment.

Adult↗
PubMed1991

[Physiopathological approach to non-ulcerative dyspepsia: clinical consequences].

Non-ulcer like dyspepsia comprises different symptoms of the upper intestinal tract with no macroscopic lesion and no identifiable etiology. Motility disturbances are the best known alterations and resemble a delay in the emptying of the stomach. Gastroesophageal reflux may produce atypical symptoms. Mucosal lesions are sometimes found which may explain the transmucosal electric potential differences. However, chronic active Helicobacter associated gastritis is usually asymptomatic. There has been no proof of psychological factors up to now. In 50% of the patients the minimum pain threshold in response to distention of the stomach is lowered. No generally accepted therapy has been found. The therapeutic principles depend on the pathogenesis of the syndrome in every individual. Medication which may enhance as well as inhibit motility may be of help.

Dyspepsia↗
PubMed1991

Abnormal perception of visceral pain in response to gastric distension in chronic idiopathic dyspepsia. The irritable stomach syndrome.

Sensory and pressure responses to gastric distension were evaluated in 24 consecutive patients suffering from chronic idiopathic dyspepsia and 20 healthy subjects. A latex balloon was placed in the proximal stomach and inflated by increments of 100 ml of air up to a maximal volume of 800 ml. Symptom response and intragastric pressure-volume curve were recorded during the gradual balloon distension. Thirteen of the 24 patients experienced pain at a distension volume less than or equal to 400 ml of air, but only one of the 20 controls (P less than 0.001). Intragastric pressure-volume curves were similar in patients and controls, and in patients with and without abnormal pain threshold, suggesting that a compliance defect was not the cause of the sensory anomaly. Gastric emptying of solids and liquids was measured in 20 of the 24 patients using a dual isotopic technique; psychological status was also evaluated in 18 patients using the Mini-Mult test. The frequency of the sensory anomaly was not different in patients with (7/14) or without (4/6) gastric stasis, but was lower in patients with (5/13) than in those without psychological disturbances (5/5, P less than 0.01). Thus, a primary visceral sensory anomaly, either alone or in conjunction with motility disturbances, can play an important role in chronic idiopathic dyspepsia and must be taken in account for further therapeutic research.

Abdominal Pain↗
PubMed1990

Effect of chronic administration of ursodeoxycholic acid on the ileal absorption of endogenous bile acids in man.

The effect of long-term administration of ursodeoxycholic acid on the ileal absorption of endogenous bile acids was determined using the tauro 23 (75Se) selena-25 homotaurocholic acid test in a controlled double-blind study involving healthy subjects (n = 15). Subjects received placebo or 13 to 15 mg/kg/day ursodeoxycholic acid for 5 wk. In the placebo group (n = 7) there was no change in the composition of serum bile acids or in the mean percentage of retention of tauro 23(75Se) selena-25 homotaurocholic acid (36.1% +/- 6.0% vs. 38.7% +/- 6.7%). In contrast, in the ursodeoxycholic acid group, serum ursodeoxycholic acid conjugates increased and the percentage of retention of tauro 23 (75Se) selena-25 homotaurocholic acid fell from 45.8% +/- 6.8% to 20.5% +/- 5.7% (p less than 0.01). We conclude that ursodeoxycholic acid administration reduces ileal absorption of endogenous bile acids. These findings provide a rational explanation for the changes in the composition of the bile acid pool during ursodeoxycholic acid therapy and could have important therapeutic implications.

Absorption↗
PubMed1990

Severe short bowel syndrome with a surgically reversed small bowel segment.

We report a case of short bowel syndrome (60 cm of jejunum anastomosed to the left colon) with reversal of the distal 15 cm of jejunum in a 21-year-old man. The nutritional absorptive capacity and digestive motility was studied for 18 months postoperatively. His absorptive capacity reached subnormal values allowing him oral nutritive autonomy and normal social life. The results of the manometric study suggested that the reversed segment delayed intestinal transit time. The prolonged contact of the chyme with the intestinal absorptive mucosa possibly increased its absorptive capacity. Our data and the literature reports suggest that reversal of a bowel loop could help wean patients from their dependence on parenteral nutrition.

Adult↗
PubMed1989

Symptomatic, radionuclide and therapeutic assessment of chronic idiopathic dyspepsia. A double-blind placebo-controlled evaluation of cisapride.

Twenty-eight patients with chronic idiopathic dyspepsia defined by the presence of chronic unexplained symptoms suggestive of gastric stasis and directly related to food ingestion were included in this prospective study. Gastric emptying of the liquid and solid phases of a meal was quantified by a dual-isotope method, and symptoms were evaluated by a diary and a visual analog scale. Delay in gastric emptying was evidenced in 59% of the dyspeptic patients; it occurred with liquids in more cases than solids. Quantitative and qualitative evaluation of symptoms was of no practical value in predicting the presence of objective stasis. The dyspeptic patients were included in a double-blind randomized controlled trial of cisapride, a new gastrokinetic drug devoid of central antiemetic effects. After six weeks of cisapride treatment, all patients with initially abnormal gastric emptying rates for liquids, and all but one for solids returned to normal ranges, and significant differences between cisapride and placebo groups were observed for half emptying times of both solids (136 +/- 16 min vs 227 +/- 32 min; P less than 0.02) and liquids (61 +/- 4 min vs 132 +/- 37 min; P less than 0.01). Cisapride also significantly improved dyspeptic symptom scores at weeks 3 and 6 of treatment as compared to those measured before treatment. Nevertheless, the decrease in global diary score was significantly higher than that seen with placebo at week 3 (-16 +/- 6 vs -1 +/- 9; P less than 0.05), but not at week 6 (-18 +/- 5 vs -10 +/- 8).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

Pathophysiological study of diarrhoea in a patient with medullary thyroid carcinoma. Evidence against a secretory mechanism and for the role of shortened colonic transit time.

Intubation techniques and scintigraphic studies were used to determine the origin and mechanism of diarrhoea in a patient with medullary thyroid carcinoma, high plasma immunoreactive calcitonin and normal circulating serotonin, substance P and prostaglandins E2 and F2 alpha. Normal function of the small intestine was found for the following: (a) absorption tests; (b) water and electrolyte absorption in the proximal jejunum; (c) 24 hour flow rate and composition of fluid entering the colon and (d) gastric emptying rate and small intestinal progression of a normal meal. By contrast, colonic function was markedly impaired in three ways: (a) water absorption was decreased by half; (b) as the main excreted solutes were organic acids, a large electrolyte gap was recorded in faecal water, and (c) colonic transit time of the meal marker was very short, and was in agreement with the rapid transit of ingested radioopaque markers. These data strongly suggest that decreased absorption in the colon secondary to a motor disturbance is the main mechanism of diarrhoea in this case of medullary thyroid carcinoma, while calcitonin induced small intestinal fluid secretion suggested earlier is either non-existent, or only of minor importance.

Adult↗