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R Jian

Publications and source records attributed to R Jian.

At least 37 records · Page 2Linked to original sources
PubMed1998

Tonic and phasic motor activity in the proximal and distal colon of healthy humans.

In healthy humans, meals stimulate phasic and tonic motor activity in the unprepared distal colon. The response of the proximal colon remains unknown. In this study, we assessed the effect of a liquid meal on proximal and distal colonic motor activity. In 12 healthy volunteers, colonic tone and phasic motility were simultaneously recorded by using an electronic barostat and perfused catheters in the fasting state and in response to a 1,000-kcal meal. The meal significantly increased the phasic activity in the distal colon (230 +/- 46% of the basal value; P = 0.02) but not in the proximal colon (138 +/- 25% of the basal value; P = 0.2). The intrabag volume of the barostat was significantly more reduced in the distal than in the proximal colon (74 +/- 11 vs. 50 +/- 9% of the basal values, respectively; P = 0.04). We conclude that the postprandial response of the unprepared proximal colon is an immediate tonic contraction that is less pronounced than in the distal colon.

Adult↗
PubMed1998

Effects of rectal distensions on nociceptive flexion reflexes in humans.

We previously showed that gastric distension inhibits the somatic nociceptive flexion RIII reflex. To explore further the viscerosomatic interactions, we tested in the present study the effects of rectal distensions on RIII reflexes. Rapid and slow-ramp rectal distensions were performed in 10 healthy volunteers with an electronic barostat. The RIII reflex was continuously recorded from the lower limb during both types of distension and from the upper limb during rapid distensions. The visceral sensations were scored on a graded questionnaire. Rapid distensions facilitated the RIII reflex recorded from the lower limb, but at the highest distension level, facilitation was followed by inhibition. Slow-ramp distension induced gradual inhibition of the RIII reflex, which correlated with both distension volume and visceral sensation. RIII reflex recorded from the upper limb was also inhibited by rapid rectal distensions. Reflex inhibitions were probably related to the activation of pain modulation systems. One plausible explanation for the facilitatory effects, observed only at the lower limb, is the convergence of rectal and reflex afferents at the same levels of the spinal cord. The differential effects of rapid and slow-ramp distensions suggest the activation of two distinct populations of mechanoreceptors by these two modes of distension.

Adult↗
PubMed1998

[Favorable outcome of a severe carcinoid cardiopathy after complete resection of the primary ovarian tumor].

Carcinoid heart disease induced by a primary ovarian carcinoid tumor is very uncommon but offers the opportunity to study its specific outcome. Indeed, unlike to other carcinoid syndromes that occur in the setting of liver metastasis, a complete removal of the primary carcinoid ovarian tumor is often possible in such cases. We report a case of severe carcinoid heart disease secondary to a carcinoid ovarian tumor. Its interest is related to the exhaustive assessment of the cardiopathy and its complete regression after removal of the ovarian tumor. This outcome emphasizes the need for a as complete as possible reduction of humoral secretions in carcinoid heart disease by medical or surgical therapies before discussing valve replacement surgery.

Aged↗
PubMed1997

Local regulation of ileal tone in healthy humans.

We previously showed that a meal induced, in the human terminal ileum, a delayed tonic relaxation, which could be related to the ileal delivery of meal residues and/or endogenous secretions released by a meal. In this study, we assessed the effects of some components of the ileal contents on its motor activity. In six healthy subjects, we studied ileal tonic and phasic motility in response to the infusion into the terminal ileum of different isotonic solutions: saline, glycochenodeoxycholic acid (GDCA), triglycerides, and short-chain fatty acids (SCFA). Tonic activity was not modified by saline, whereas it was significantly decreased by GDCA and triglycerides (maximal increase in intrabag volume 139 +/- 7% and 152 +/- 16%, respectively, P < 0.01), and significantly increased by SCFA (maximal decrease in intrabag volume 72 +/- 4%, P < 0.01). No significant change of phasic activity was evidenced with either solution. We conclude that 1) bile acids and triglycerides not absorbed in the more proximal gut could be involved in the ileal relaxation occurring after eating and 2) local stimulation of chemoreceptors is of importance in the regulation of ileal motility.

Adult↗
PubMed1996

Ileal absorption of bile acids in patients with chronic cholestasis: SeHCAT test results and effect of ursodeoxycholic acid (UDCA).

The effect of cholestasis on ileal bile acid absorption is controversial in animal models (up- or down-regulation) and unknown in humans. We therefore studied values of the selena homotaurocholic acid (SeHCAT) test before and after long-term administration (>3 months, 13-15 mg/kg/day) of ursodeoxycholic acid (UDCA) in 27 patients with chronic cholestatic liver diseases (24 women, 3 men; mean age, 50 years; 24 primary biliary cirrhosis, 2 secondary biliary cirrhosis, 2 others). The control group consisted of 14 healthy volunteers. Seven-day SeHCAT percentage retention was identical in the 12 untreated cholestatic patients (serum bilirubin, 75+/-42 micromol/L, alkaline phosphatase, 4.2+/-1.0 N; mean+/-SEM) and in the control group (43.6+/-2.9 and 43.8+/-4.2%, respectively). In the 22 patients treated by UDCA for 38+/-8 months, SeHCAT percentage retention was 20.3+/-3.0%. In the seven patients with the SeHCAT test done before and after UDCA treatment (16+/-5 months), SeHCAT percentage retention decreased significantly under UDCA therapy (42.0+/-4.4 vs 19.4+/-4.1%; P < 0.02). We conclude that, in patients with chronic cholestasis (1) SeHCAT percentage retention is not altered-taken together with the known defect of biliary excretion, this lack of increase in SeHCAT percentage retention argues against up-regulation of bile acid ileal transport; and (2) UDCA treatment induces a decrease in the SeHCAT percentage retention-this effect may be related primarily to a decreased bile acid ileal absorption.

Alkaline Phosphatase↗
PubMed1996

Effect of the kappa agonist fedotozine on perception of gastric distension in healthy humans.

BACKGROUND AND AIM: Gastric hypersensitivity to mechanical distension has been observed in functional dyspepsia, but no drug is available that specifically acts on gastric afferent pathways to decrease gastric nociception. The aim of this study was to assess the effect of fedotozine, a synthetic ligand for peripheral kappa receptors, on human gastric sensitivity. METHODS: Twenty-seven healthy volunteers were randomized to receive either fedotozine (30 mg t.d.s.) or a placebo, for 7 days. On day 7, the effects of fedotozine were tested on discomfort threshold and gastric compliance during graded isobaric and isovolumic distensions. In 16 of these subjects, the effect of this drug was tested on somatic sensitivity. In 10 other healthy volunteers the effect of fedotozine on gastric distension-induced inhibition of the RIII reflex, a process closely related to visceral sensitivity, was also studied. RESULTS: During isobaric distensions, the discomfort threshold was significantly higher in subjects on fedotozine than in those on placebo (14.4 +/- 0.92 vs. 12.0 +/- 1.13 mmHg; P = 0.04). Compared to placebo, fedotozine did not modify gastric compliance and somatic sensitivity. Fedotozine also reduced the inhibition of the RIII reflex induced by gastric distension. CONCLUSION: Fedotozine decreases gastric sensitivity to distension by exerting specific action on gastric afferent pathways.

Adult↗
PubMed1996

Effect of glucose and lipids on intestinal absorption of sorbitol: role of gastric emptying.

The aim of our study was to test the hypothesis that the better absorption of sorbitol when ingested with glucose could be related to a delayed gastric emptying. We tested the effect of the ingestion of glucose and lipids on the gastric emptying and intestinal absorption of sorbitol in six healthy volunteers, using gastric scintigraphy and hydrogen breath test. After an overnight fast, subjects ingested in random order, on 48-h test periods separated by at least one week, the following solutions: (a) 20 g sorbitol alone; (b) 20 g sorbitol and 20 g glucose; (c) 20 g sorbitol and 9 g lipids. Isotopic acquisitions were taken for 3 h following the ingestion of sorbitol labelled with 111Indium. Hydrogen concentration was measured in end-expiratory samples during 5 h, and the areas under the breath hydrogen curve, reflecting the amounts of sorbitol unabsorbed in the small bowel, were compared between periods. Mean area under the curve was 397 +/- 159 when sorbitol was ingested alone, and this was significantly lower when ingested with glucose or lipids (313 +/- 181 and 337 +/- 135, respectively; P < 0.05). The three curves of sorbitol gastric emptying differed significantly from each other, the gastric emptying being the slowest for sorbitol plus lipids, and the fastest for sorbitol taken alone. We found a positive correlation between the half-emptying time and the hydrogen areas under the curve (r = 0.46, P = 0.05). In conclusion, our study demonstrates that adding glucose or lipids to a solution of sorbitol slows the gastric emptying of sorbitol, resulting in a better intestinal absorption of sorbitol.

Adult↗
PubMed1996

Treatment of the carcinoid syndrome with the longacting somatostatin analogue lanreotide: a prospective study in 39 patients.

BACKGROUND: Somatostatin analogues effectively control flushing and diarrhoea in patients with the carcinoid syndrome. The octapeptide lanreotide is available in slow release form, which could eliminate the necessity of twice a day injections as with octreotide. PATIENTS AND METHODS: 39 patients with carcinoid syndrome were included in a prospective multicentre study. Patients received lanreotide 30 mg intramuscularly every 14 days for six months. The number and intensity of flushing episodes and bowel movements, urinary 5 hydroxy-indolacetic acid (5 HIAA) concentrations, and variations of tumour mass were recorded. RESULTS: After one month of treatment, flushing episodes (median (range)) decreased significantly (3 (0.3-24) episodes per day v 1 (0-15), p = 0.04) and completely resolved in 39% of the patients. A significant decrease was seen in the number of bowel movements and discomfort related to diarrhoea. Urinary 5 HIAA concentrations were unchanged in 57% of the patients and decreased in 18%. After six months of treatment, the actuarial proportions of patients with at least a 50% decrease in the number of flushing episodes and bowel movements were 54% and 56%, respectively. Forty two per cent of the patients who were treated for six months had at least a 50% reduction in 5 HIAA values. No clear signs of regression of tumours were seen in any of the patients. Lanreotide was well tolerated despite transient mild pain or erythema at the injection site in 25% of the patients. Biliary lithiasis appeared in two patients after six months of lanreotide. CONCLUSION: Lanreotide, 30 mg intramuscularly every other week, is an effective and convenient treatment in patients with the carcinoid syndrome.

Biomarkers, Tumor↗
PubMed1996

[Anti-endomysium and anti-reticulin antibodies in adults with celiac disease followed-up in the Paris area].

OBJECTIVES: Circulating IgA class anti-endomysium and anti-reticulin antibodies are reliable serological markers for the diagnosis of coeliac disease. The aim of this study was to evaluate their diagnostic sensitivity and specificity, and their prevalence in a group of coeliac adults taking a gluten-free diet followed in Ile-de-France. METHODS: One hundred and forty-five sera from 134 patients were examined for IgA and IgG anti-endomysium and anti-reticulin antibodies by indirect immunofluorescence. Sixty-eight patients were confirmed coeliacs; 8 patients with noncoeliac (unresponsive to a gluten-free diet) duodenal villous atrophy and 58 patients with no villous atrophy served as controls. RESULTS: In active coeliac disease, the sensitivity of anti-endomysium and anti-reticulin antibodies was 88% and 50%, respectively. Their specificity was 100%: they were never detected in case of noncoeliac villous atrophy. Under a strict gluten-free diet, their prevalence was 7% and 0%, respectively. CONCLUSION: In the studied population, the diagnosis accuracy of IgA anti-endomysium antibodies confirms their usefulness in screening and follow-up of coeliac disease. The absence of anti-endomysium and anti-reticulin antibodies in those cases with noncoeliac villous atrophy suggests that in the latter, different immunopathologic mechanisms, as compared with coeliac disease, are concerned.

Adolescent↗
PubMed1995

Motor activity recorded in the unprepared colon of healthy humans.

A manometric method was developed to study the motor activity in the unprepared human colon, and the results in eight healthy subjects were compared with those obtained in the same subjects after bowel cleansing with a non-absorbable solution containing polyethylene glycol 4000 (PEG). A tube assembly (4.5 m long, 12 lumen) was introduced through the nose and passed through the gastrointestinal tract. Two manometric recordings were performed one month apart, one without any preparation and the other after bowel cleansing with PEG. There was no obvious qualitative difference between the recordings performed in the uncleansed and PEG cleansed colon. Moreover, in the unprepared colon motility indices were close to those measured in the cleansed colon. The number of high amplitude propagated contractions (mean (SEM)) was, however, higher in the cleansed colon (8.6 (2.8) v 5.4 (1.8)/subject/9 h in the unprepared colon; p < 0.04). It is concluded that in healthy subjects taking a regular diet, motor activity is not different between the uncleansed and cleansed colon with PEG, except for the high amplitude propagated contractions, which occur more frequently in the cleansed colon.

Adult↗
PubMed1994

Inhibition of a somatic nociceptive reflex by gastric distention in humans.

BACKGROUND/AIMS: The spinal nociceptive RIII reflex, an exteroceptive cutaneous-muscular flexion reflex, is powerfully and specifically inhibited by painful heterotopic somatic stimuli. The aim of the present study was to evaluate the effects of nonpainful and painful visceral stimuli on this reflex. METHODS: In nine healthy volunteers, the effects of five levels of gastric distention were tested on the RIII reflex, recorded from the biceps femoris, and elicited by electrical stimulation of the ipsilateral sural nerve. Distentions were performed by means of a balloon that was placed in the proximal part of the stomach and connected to an electronic barostat. The sensations evoked by gastric distention were scored using a graded (0-6) questionnaire. RESULTS: The 200- and 400-mL distention levels elicited no significant modifications of the RIII reflex; the 600-, 800-, and 1000-mL levels inhibited the RIII reflex by 25%, 35%, and 55%, respectively. The magnitude of this inhibition correlated significantly (P < 0.0001) with both the level of distention and the intensity of visceral perception. CONCLUSIONS: Gastric distention produces volume-dependent inhibition of the somatic RIII reflex in humans. This model may provide an interesting tool for objective and quantitative evaluation of normal and disturbed visceral sensations in humans.

Adult↗