Biomedical subjects

L Grossi

Publications and source records attributed to L Grossi.

At least 37 records · Page 2Linked to original sources

PubMed1998

Proximal and distal gastric distension in normal subjects and H. pylori-positive and -negative dyspeptic patients and correlation with symptoms.

Aim of the study was to analyze gastric distension with water in H. pylori-positive and -negative dyspeptic patients and normal subjects and the correlation with symptoms. Twenty dyspeptic patients and 19 normal subjects were studied. H. pylori was determined in each dyspeptic patient with the rapid urea test at endoscopy. Gastric distension was evaluated by real-time ultrasonography with the ingestion of stepwise-increasing amounts of water up to a total of 600 ml. During distension, the symptom score was evaluated as well. The proximal stomach was significantly smaller in dyspeptic patients than in healthy controls, at 100-600 ml water (P<0.01). A larger distal stomach was observed at 500 and 600 ml of water (P<0.01). The score of bloating and fullness was greater in dyspeptics than in controls at 300 and 600 ml of water distension. The symptoms score was linearly correlated with proximal and distal gastric measurements in dyspeptic patients and in controls. No significant difference was found in dyspeptic patients regarding the H. pylori status. In conclusion, dyspeptic patients show a defective adaptation of the whole stomach to water distension and an increased symptom perception score as compared to controls. H. pylori infection does not seem to be a determining factor in these observed findings.

Adult↗

PubMed1998

Swallows, oesophageal and gastric motility in normal subjects and in patients with gastro-oesophageal reflux disease: a 24-h pH-manometric study.

BACKGROUND: the motor aspects underlying gastro-oesophageal reflux disease (GORD) are still not completely clear. AIM: to evaluate the relationship between oesophageal and gastric motility in GORD patients. PATIENTS: twelve patients with grade I-II oesophagitis, mean age 45 yr, and 10 healthy subjects, mean age 42 yr, were studied. METHODS: a pH-manometry was performed to analyse oesophageal and gastric motility, swallows and oesophageal pH values for the whole 24-h period, and for the 2-min period before and after each reflux episode. RESULTS: as compared to controls, GORD patients showed in the 24-h period, a greater number of swallows (P < 0.01) and a lower percentage of post deglutitive propagated oesophageal body waves (P < 0.05). The number of migrating motor complexes (MMC) was similar in the two groups, with a lower amplitude of phase III gastric waves in GORD. During MMC reflux episodes were seen only in GORD patients. After refluxes an increase in swallows, simultaneous and secondary oesophageal waves were detected in GORD patients, with a reduction of primary peristalsis. Isolated gastric contractions preceded reflux episodes more frequently in GORD patients than in controls. CONCLUSIONS: GORD patients showed an increase in swallows with altered post-deglutitive oesophageal motility and a reduced amplitude of gastric MMC. Moreover small contractions of gastric antrum are present before acid refluxes, suggesting a multifactorial pathogenesis of the disease.

Adult↗

PubMed1998

Anti-Helicobacter pylori specific antibody immunohistochemistry improves the diagnostic accuracy of Helicobacter pylori in biopsy specimen from patients treated with triple therapy.

OBJECTIVE: To investigate the effectiveness of immunohistochemical technique to detect Helicobacter pylori (H. pylori) in patients treated with triple therapy. METHODS: Forty patients (18 men, 22 women, mean age 43 years) with active antral gastritis, H. pylori positive at urease test, culture, and histology, were treated for 1 wk with omeprazole, amoxicillin, and metronidazole. Gastritis was scored according to Sydney criteria. Two months after the end of therapy, endoscopy, urease test, culture, and histology were repeated. RESULTS: Culture and histology were negative in 32 (80%) of treated cases. Biopsy specimens of the eradicated group were stained with immunohistochemical technique using an anti-H. pylori specific polyclonal antibody. In 12 of 32 (37.5%) patients, clusters of round or vibrio-shaped bacteria, unidentified at histology, were stained by the specific anti-H. pylori antibody. After triple therapy, at histology all patients were found with improved gastritis. In six patients however, mucosal-associated lymphoid tissue (MALT) appearance, present before therapy, persisted after therapy. In five of six patients with MALT, immunostaining with anti-H. pylori antibody was positive. CONCLUSIONS: The immunohistochemical technique is more accurate than classical methods in identifying H. pylori after specific therapy. This method should, therefore, be used in all studies that aim to achieve eradication. Whether the H. pylori identified at immunohistochemistry is able to reactivate and induce recrudescence of infection remains to be clarified.

Adult↗

PubMed1996

Relationship between gastric and gallbladder emptying and refilling in normal subjects and patients with H. pylori-positive and -negative idiopathic dyspepsia and correlation with symptoms.

Gastric and gallbladder emptying and refilling was studied in 10 normal subjects and in 38 dyspeptic patients. H. pylori was determined in each dyspeptic on mucosal antral biopsy performed during endoscopy. Gastric and gallbladder emptying was evaluated by real-time ultrasonography. Normal subjects were evaluated after two solid-liquid meals of 340 kcal and 680 kcal. Dyspeptics were studied after the 340-kcal meal only. For each subject and patient, minimum gallbladder volume and percentage of gastric emptying at this point was determined. Gastric and gallbladder slope was also drawn, and the crossing point between the two slopes identified. In normal subjects with the 340-kcal and 680-kcal meal, minimum gallbladder volume occurred for a similar percentage of gastric emptying. The crossing point between the two slopes was computed at the same percentage of gastric and gallbladder refilling with both meals. With the 680-kcal meal, however, peak gallbladder contraction and the crossing point between the two slopes occurred significantly later than with the 340-kcal meal (P < 0.05). In dyspeptics with the 340-kcal meal, the parameters evaluated were similar to the ones computed in controls after the meal of 680-kcal, suggesting delayed gastric emptying and gallbladder refilling. The presence or absence of H. pylori and symptom score were not correlated with any of the parameters studied.

Adult↗

PubMed1996

Increase of swallows before onset of phase III of migrating motor complex in normal human subjects.

The aim of our study was to analyze the relation between the deglutitive activity and fasting esophageal and gastric motility in normal subjects. Fifteen healthy subjects (9 males, 6 females) with a mean age of 42 years (range 19-65) were studied. A 24-hr pH-manometric recording was performed using a probe with four solid-state recording sites 10 cm apart, placed so as to record the motor activity of esophageal body, lower esophageal sphincter (LES) or distal part of the esophagus, and gastric antrum. An additional probe with one recording site was placed in the pharynx to evaluate swallowing. A pH electrode was also placed at 5 cm above the sphincter. Data were transferred to a personal computer and analyzed using specific software. Subjects received two meals during the recording session. MMCs were almost exclusively recorded during the nighttime. A mean of 2 +/- 0.94 (SD) MMC per subject was detected with a mean (+/- SD) interval, between each cycle, of 86.11 +/- 34.53 min. During the 30 min preceding gastric phase III, the number of swallows showed an increase that reached statistical significance 5 min before the onset of phase III. A similar pattern was observed for the area under the curve (AUC) of the esophagus and LES. In conclusion deglutition and esophageal motility vary with the MMC, suggesting that the deglutitive activity is part of the interdigestive motility pattern.

Adult↗

PubMed1996

Effect of nitric oxide on propagated clusters of spontaneous motor waves in an ex vivo rabbit intestinal preparation.

The aim of this study was to determine whether nitric oxide can play a role in regulating the propagation of spontaneous motor activity in a rabbit intestinal preparation completely excluded from any central and vascular connection. Experiments were done on nine rabbits of either sex, weighing 2.5 +/- 0.5 kg (mean +/- SD). After one week of semiliquid diet the animals were sacrificed and a segment including the stomach, duodenum and part of the jejunum was removed and placed into a single chamber organ bath containing 1 L of oxygenated Krebs' solution. Four strain gauges connected to a Dynograph Recorder were sutured on the serosal surface 10 cm apart starting from the gastric antrum to the distal duodenum. Once the motor activity was stabilized, N-nitro-L-arginine methyl-ester (L-NAME) was added to the bath at increasing concentration from 10(-7) to 10(-4) M. Spontaneous motor activity was recorded, characterized by the cycling occurrence of bursts of waves, starting from the stomach and propagating to the descending duodenum. L-NAME at higher concentrations reduced the time interval between the bursts of waves with a concomitant increase in the propagation velocity of the motor activity. No change in the frequency of waves was detected. The effect of L-NAME was prevented by the administration of L-Arginine. This study suggests an important role for the nitric oxide pathway in the distal propagation of the spontaneous motor activity of the alimentary tract.

Animals↗

PubMed1996

Different effects of calcitriol and parathyroidectomy on the PTH-calcium curve in dialysis patients with severe hyperparathyroidism.

BACKGROUND: The PTH-calcium sigmoidal curve is shifted to the right, the slope of the curve is steeper, and the set point of calcium is increased in dialysis patients with secondary hyperparathyroidism, compared to patients with low-turnover bone disease. These findings could be related to increased parathyroid cell mass and increased sensitivity of parathyroid cells to serum calcium variations in these patients. Calcitriol therapy has been documented to reduce PTH levels by shifting the curve to the left and downward. The effect of a surgical reduction of parathyroid gland mass on the PTH-calcium curve has not yet been investigated. In this study we compared the effects of calcitriol and subtotal parathyroidectomy (PTH) on the dynamics of PTH secretion in response to acute changes of serum calcium in two groups of dialysis patients with severe hyperparathyroidism. METHODS: Fourteen dialysis patients treated for 6 months with high-dose i.v. calcitriol (1-2 micrograms thrice weekly, and 10 dialysis patients who underwent subtotal PTx were studied. The PTH-calcium relationship obtained by inducing hypo- and hypercalcaemia means of low and high calcium dialysis was evaluated before and 2-6 months after treatment. RESULTS: Both calcitriol and subtotal PTx significantly decreased PTH (respectively from 797 +/- 595 to 380 +/- 244 and from 1036 +/- 250 to 70 +/- 34 pg/ml), as well as maximal PTH response to hypocalcaemia (PTHmax), and maximal PTH suppression during hypercalcaemia ( PTHmin). When the PTH-calcium curves were constructed using PTHmax as 100% to factor for differences in absolute PTH levels and to provide an assessment of individual parathyroid cell function, a shift of the sigmoidal curve to the left and downward, and a significant decrease in the set point of ionized calcium (from 1.31 +/- 0.05 to 1.26 +/- 0.05 and from 1.36 +/- 0.09 to 1.22 +/- 0.07 mmol/l) was documented with both treatments. However, the slope of the PTH-calcium curve increased after subtotal PTx indicating that the sensitivity of the parathyroid cell to serum calcium changes increased with PTx, while on the contrary it decreased with calcitriol. CONCLUSIONS: PTH secretion decreases proportionally more with calcitriol than with surgery for a given decrease in the functional mass of parathyroid cells. The change in the PTH-ICa sigmoidal curve induced by subtotal PTx is due to the removal of a large mass of parathyroid tissue with advanced hyperplasia.

Calcitriol↗

PubMed1995

Short- and long-term omeprazole for the treatment and prevention of duodenal ulcer, and effect on Helicobacter pylori.

OBJECTIVE: This study analyzes the effect of short- and long-term omeprazole (OM) on duodenal ulcer healing, recurrence, and H. pylori status. METHODS: Patients affected by active duodenal ulcer were randomly allocated to treatment with OM 20 mg or 40 mg once daily for 4 wk. Subsequently, patients with healed duodenal ulcer were randomly assigned to one of the following three groups: OM 20 mg once daily for 12 months, OM 20 mg alternate days for 12 months, and no treatment. Endoscopy was performed at entry, at 4 wk, and after 4, 8, and 12 months. Two biopsy specimens from antrum, body, and fundus were taken for histology and search for H. pylori. One hundred and eighty patients with active duodenal ulcer were admitted. Ninety-one were treated with OM 20 mg once daily and 89 with OM 40 mg for 4 wk. RESULTS: The results at 4 wk show 92.8% patients healed with OM 20 mg and 95.1% at 40 mg (NS). In the second part of the study, 96 of the patients who healed at 4 wk (45 with OM 20 mg, and 51 with OM 40 mg) entered the long-term study. Thirty-six patients received OM 20 mg daily for 12 months, 35 OM 20 mg on alternate days for 12 months, and 25 patients no treatment. The results show a healing rate of 100%, 100%, and 95% with OM 20 mg daily, of 97%, 95%, and 93% with OM 20 mg on alternate days, and of 81%, 50%, and 40% (p < 0.01) with no treatment at 4, 8, and 12 months, respectively. H. pylori that was found in 97% of patients at entry, at 4 wk was found in 92.8% of patients treated with OM 20 mg and in 97.5% of patients treated with OM 40 mg (NS). In one-third of the patients, H. pylori disappeared from the antrum but was found in the fundus. A 30% reduction in the presence of H. pylori was seen in the group treated with 20 mg daily for 12 months. CONCLUSIONS: We conclude that both continuous and alternate-day long-term OM treatment at 20 mg are similarly efficacious in the prevention of duodenal ulcer recurrence. Healing active duodenal ulcers with 20 or 40 mg does not influence subsequent treatment. Long-term OM at 20 mg daily for 12 months suppresses H. pylori temporarily in one-third of the patients. In these patients however, H. pylori reactivates after the end of treatment.

Adult↗

PubMed1994

Effect of cimetropium bromide on esophageal motility and transit in patients affected by primary achalasia.

The effect of cimetropium bromide, a new anticholinergic agent, in patients with primary achalasia was studied. Twenty such patients (12 females and 8 males, mean age 38 years, range 15-56) were studied. Diagnosis was performed by radiology, endoscopy, and manometry. Lower esophageal sphincter pressure and body wave amplitude were measured by means of a five-channel catheter constantly perfused by a low-compliance pneumohydraulic pump. Patient received cimetropium bromide 10 mg intravenously over 3 min or placebo in a double-blind manner. In five patients esophageal transit evaluated by scintiscanning was studied on separate occasions after cimetropium bromide or placebo. Baseline mean lower esophageal sphincter pressure was 46 +/- 5 mm Hg and mean amplitude of body waves was 30 +/- 8 mm Hg. Cimetropium bromide induced a significant decrease in sphincter pressure and body wave amplitude that measured 13 +/- 3 mm Hg and 8 +/- 4 mm Hg, respectively, 15 min after the end of infusion. The decrease was maintained for 45 +/- 5 min. A marked reduction in repetitive body waves was also noted. Esophageal transit was also accelerated with cimetropium bromide. Maximal stomach radioactivity was observed after 8 +/- 1.8 sec while with placebo this was reached after 65 +/- 1.5 sec (P < 0.01). It is concluded with cimetropium bromide reduces LES pressure and shortens transit in primary esophageal achalasia. It may be useful in the treatment of this esophageal motility disorder.

Adolescent↗

PubMed1994

Migrating motor complex recorded spontaneously and induced by motilin and erythromycin in an ex vivo rabbit intestinal preparation.

We investigated basal motility and the motor effects of motilin, erythromycin, and prostigmine on segments of rabbit gastrointestinal tract removed from extrinsic neural and vascular pathway and immersed in an oxygenated organ bath. Motility was recorded by means of four strain gauges sutured on the serosal surface of the segment. During basal recording, clusters of duodenal contractions that propagated distally, resembling phase III activity of migrating motor complex, were seen. Motilin (10(-6) M) and erythromycin (10(-6) M) induced a propagated cluster of contractions similar to the phase III recorded during the basal period. Prostigmine (10(-6) M) induced a simultaneous increase in gastric and small intestinal motility. Atropine (10(-5) M) prevented the motor effect of motilin, erythromycin, and prostigmine. Thus, MMCs do not appear to require central input for initiation and propagation. Motilin and erythromycin stimulate MMCs through an enteric cholinergic mechanism; therefore, the previously reported smooth muscle receptors for both substances were not apparent in the ex vivo preparation.

Animals↗

PubMed1994

H2-receptor antagonists are scavengers of oxygen radicals.

Potential oxygen radical scavenging properties of the H2-receptor antagonists cimetidine, ranitidine and famotidine were investigated. These drugs, although ineffective against superoxide anion and hydrogen peroxide, can scavenge hydroxyl radical (OH.) with a very high rate constant, which is about tenfold higher than that of the specific scavenger mannitol for famotidine (1.7 x 10(10) mol-1 s-1) and cimetidine (1.6 x 10(10) mol-1 s-1), ranitidine displaying a rate constant of 7.5 x 10(9) mol-1 s-1. These OH. savenging effects are significant beginning from 10, 28 and 100 mumol l-1 concentration for famotidine, cimetidine and ranitidine, respectively, thus suggesting that the drugs may effectively act as OH. scavengers in vivo especially in the gastric lumen. Only cimetidine can apparently bind and inactivate iron, which further emphasizes its antioxidant capacity. Moreover, all drugs, even at 10 mumol l-1 concentration, show powerful scavenging effects on hypochlorous acid and monochloramine, which are cytotoxic oxidants arising from inflammatory cells, such as neutrophils. These data suggest that some therapeutical effects of H2-receptor antagonists in peptic ulcer may also be related to their antiradical-antioxidant capacity, and that these drugs could potentially be used in other disease entities characterized by free radical-mediated oxidative stress in vivo.

Chloramines↗

PubMed1993

On the specificity of altered muscle function in experimental colitis in rats.

BACKGROUND: Studies on muscle contraction in colitis yield conflicting data that may reflect differences in the manner in which colitis is induced. Therefore, we compared distal colonic longitudinal muscle contraction in four models of colitis in the rat. METHODS: Distal colitis was induced by intrarectal administration of trinitrobenzene sulfonic, acetic acid, or Trichinella spiralis larvae, or by intraperitoneal injection of mitomycin C. Colonic myeloperoxidase activity was used to monitor acute inflammation. RESULTS: Myeloperoxidase activity increased in each model of colitis. In trinitrobenzene-treated rats, contractile responses to carbachol, substance P, and KCl decreased by 64%, 76%, and 58%, respectively. In acetic acid treated rats, responses induced by carbachol, substance P, or KCl were each significantly decreased by 73%, 68%, and 55% and were similarly reduced by 42%, 77%, and 46%, respectively, in rats with T. spiralis colitis. In mitomycin-induced colitis, these respective responses also decreased significantly by 71%, 55%, and 54%. CONCLUSION: Decreased contractility of longitudinal muscle in acute colitis in rats is independent of the manner in which the colitis is induced and is mediated at a receptor-independent locus on the muscle cell.

Acetates↗

PubMed1993

[Efficacy and tolerability of cisapride in a new formula of 10 mg effervescent capsules for the treatment of functional dyspepsia].

The efficacy and tolerability of Cisapride effervescent granules and a metoclopramide-dimethicone combination were compared double-blind in two comparable groups of 15 patients each with dyspepsia. All patients received three sachets daily of either drug for 6 consecutive weeks. As for efficacy, Cisapride effervescent granules was found to reduce 85% (11/13) of symptoms to a statistically significant extent, as against 42% (5/12) in the reference group. Statistical analysis showed Cisapride effervescent granules to be more effective than the reference drug for 6 out of 11 evaluable symptoms. Mean global improvement was 86% for Cisapride effervescent granules vs 41% for the reference combination. Final judgment by the physician was more favorable for Cisapride effervescent granules than for the reference drug (p < 0.0001). Treatment withdrawal was never necessary and no significant changes of laboratory values were observed. No statistically significant difference between the two treatments as to tolerability was observed. In conclusion, Cisapride effervescent granules was found to have a better risk/benefit ratio than the reference combination.

Adult↗

PubMed1993

[A new granular effervescent 10-mg formulation of cisapride in the treatment of gastroesophageal reflux].

The efficacy and tolerability of Cisapride effervescent granules for treatment of gastroesophageal reflux disease were compared to a metoclopramide-dimeticone combination. The double-blind study was performed in two groups of 10 patients each who received 3 sachets daily of either drug for 8 weeks. Cisapride effervescent granules induced a statistically significant improvement of 75% of symptoms (6/8) while this improvement was obtained with the reference drug for only 60% (3/5). Statistical evaluation showed Cisapride effervescent granules to be more effective than the reference drug for 2 of 5 evaluable symptoms; mean global improvement amounted to 83 vs 58%. Final physician opinion was more favorable to Cisapride effervescent granules than to the reference drug (p < 0.005). Treatment did not have to be withdrawn nor were clinically significant changes of laboratory values observed. Both drugs were found to be well tolerated without differences between the two groups. Three patients treated with Cisapride effervescent granules complained of short-lasting mild abdominal discomfort the relations of which to the drug was doubtful, and which subsided spontaneously without need to withdraw treatment or to apply other types of therapy.

Adult↗

PubMed1991

Enhanced clearing of Helicobacter pylori after omeprazole plus roxithromycin treatment.

The in vitro antibacterial activity of omeprazole against eight strains of Helicobacter pylori was evaluated. Minimum inhibitory concentration (MIC) values were 32 micrograms/ml and 64 micrograms/ml (MIC50 and MIC90 respectively). We performed a randomized single blind study comparing the efficacy of omeprazole alone (for 4 weeks) or combined with roxithromycin (for 2 weeks) in the treatment of duodenal ulcer and chronic active gastritis associated with H. pylori infection, H. pylori was eradicated in 75% of patients treated with omeprazole alone whereas the patients treated with the combination of these drugs were completely free from H. pylori at the end of the therapy.

Drug Combinations↗

PubMed1990

Effects of cimetropium bromide on gallbladder contraction in response to oral and intraduodenal olive oil.

To evaluate the influence of the stomach and the cholinergic system on gallbladder contraction induced by physiological stimuli, the reduction in gallbladder volume in 7 healthy volunteers has been studied by real-time ultrasonography after the oral and intraduodenal administration of olive oil, preceded by pretreatment with cimetropium bromide or placebo. After an overnight fast, each subject swallowed 50 ml olive oil or it was administered through a naso-duodenal tube in the proximal duodenum. Cimetropium bromide 5 mg or placebo was given intravenously under double-blind control. After the placebo pretreatment, gallbladder contraction was greater and faster after intraduodenal oil than after oral oil. Cimetropium bromide decreased the extent, velocity and duration of gallbladder contraction induced by intraduodenal olive oil but it only reduced the velocity of the contraction induced by oil given orally. It is concluded that in normal human subjects the stomach modulates the extent and velocity of postprandial gallbladder contraction and that anticholinergic agents antagonize the gastric and duodenal phases of the response of the gallbladder to a meal.

Administration, Oral↗

PubMed1990

Tertiary alkyl amines: an autoxidation-dealkylation process. II.

Autoxidation of tertiary alkyl amines is not a common process: E.S.R. evidences support a base-catalyzed process. Several tertiary alkyl amines/water systems have been investigated in order to verify the generality of such a process, if some requests are satisfied.

Amines↗

PubMed1988

Determination of serum cholesterol on the Reflotron (BBR) dry chemistry analyser. Assessment of accuracy.

This investigation is aimed at assessing the accuracy of S-cholesterol determination by means of the Reflotron, an analytical system based upon the dry chemistry approach. Two sets of sera, one of them including specimens with elevated concentrations of urea, creatinine, glucose, urate or bilirubin, were assayed in parallel with the Refloton system, with a class-A "reference" method (including alkaline hydrolysis and extraction) and with a routine liquid chemistry enzymatic method. Results for both sets of sera indicated good agreement of the tested system with the routine method, whilst a small proportional negative bias was observed in comparison with the "reference" method. The use of the reference method as a basis for comparison allows more conclusive statements about accuracy to be made.

Autoanalysis↗