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L Altomonte

Publications and source records attributed to L Altomonte.

At least 55 records · Page 3Linked to original sources

The role of cAMP and prostaglandins in gastric acid secretion after pentagastrin administration.

The role of cAMP and prostaglandins as specific intracellular effectors of gastrin action at the level of the parietal cells has not been sufficiently clarified. For this reason we studied the responses of the parietal cells to stimulation with pentagastrin (6 micrograms/kg i.m.) during theophylline infusion (which causes an increase in the intracellular cAMP) and during acetylsalicylic acid infusion (which inhibits the prostaglandin synthesis) in 28 healthy volunteers. Both theophylline and acetylsalicylic acid provoked a significant increase of gastric acid secretion after pentagastrin. Our results suggest that: 1. an increase in intracellular cAMP may be the basis of the stimulatory effect of gastrin on gastric acid secretion 2. a decrease in the synthesis of prostaglandins may lead to a greater gastric acid response after pentagastrin.

Adolescent↗

Evidence of extragastric gastrin release in postoperative ulcer patients.

The principal sites of gastrin production in man are localized at the level of the gastric antrum; both the oral glucose load and the protein meal stimulate the gastrin secretion. The aim of this study was to verify the gastrin response in patients with gastric resections presented with various stimuli. In the operated patients, the behavior of serum gastrin after a protein meal was different with respect to that observed in control subjects. After glucose, on the contrary, a very similar result was seen when compared to controls. The increase in serum gastrin of patients with Billroth II provides a further confirmation of an extragastric origin of gastrin.

Dietary Proteins↗

The effect of lysine acetylsalicylate on somatostatin inhibition of insulin secretion induced by arginine.

The inhibitory effect of somatostatin (SRIF) on immunoreactive insulin release and on many other hormonal secretions has been widely studied in both animal and man. However, the mechanism by which SRIF acts on these functions remains poorly defined. Aim of this study is to determine the inhibitory effect of SRIF on insulin secretion induced by arginine after the administration of lysine acetylsalicylate (LAS) in a dose which inhibits the endogenous synthesis of prostaglandins. Ten healthy informed volunteer subjects were studied. Four studies were carried out in randomized order, each one separated by a three day interval. The first study was a test of arginine (25 g i.v. in 30 min). The second study was a test of arginine with SRIF infusion (150 micrograms bolus followed by 100 micrograms/h for 120 min). The third study was a test of arginine with an infusion of SRIF and LAS (66 mg/min for 120 min). The fourth study was a test of arginine with LAS infusion. Plasma insulin levels were determined by radioimmunoassay. After arginine administration the typical biphasic insulin response was observed with a precocious peak at 3 min and a late peak at 30 min. This response is not significantly modified under LAS infusion. With the infusion of SRIF at a dose of 100 micrograms/hr after arginine administration only a very modest insulin response was observed. The addition of LAS does not modify the inhibitory effect of SRIF on insulin secretion induced by arginine. This result demonstrates that the inhibitory action of SRIF on the secretion of insulin is not dependent upon the activation of the endocellular prostaglandin system.

Adult↗

Stimulatory effect of pentagastrin on growth hormone and prolactin secretion in normal subjects.

Gastrin-like immunoreactive substances have been reported as occurring in both digestive tract tissues and nervous system, including the hypothalamus and the anterior and posterior pituitary. The carboxyterminal tetrapeptide shared by gastrin and cholecystokinin, which represents the bioactive site of both hormones, has been shown to be a secretagogue for insulin and glucagon and it might have a neurotrasmitter function. As small gastrin-like peptides may also play a role in the regulation of anterior pituitary hormones, the present study deals with the in vivo effect of pentagastrin on the release of growth hormone (GH) and prolactin (PRL). Six healthy volunteer males and six healthy volunteer females were studied. All females subjects were in the early follicular phase of the normal menstrual cycle and all subjects were not taking or had been taking any drug known to affect GH or PRL secretion. A continuous intravenous infusion of pentagastrin (1.5 micrograms/kg/h) was administered to all the subjects for a time of 3 hours. In males pentagastrin infusion resulted in a significant increase in GH concentration from basal values (P less than 0.01 at 60 min). In females pentagastrin infusion did not affect GH levels. PRL levels were not affected at all by intravenous pentagastrin infusion both in males and females. The exact understanding of pentagastrin action on GH release awaits further investigation. The different pattern between male and female subjects suggests a sexual hormone influence on the hypothalamic-pituitary sites of action of pentagastrin in vivo. Our data did not confirm a stimulatory effect of pentagastrin on PRL secretion in normal subjects.

Adult↗

[Behavior of GH and prolactin during enflurane anesthesia and neuroleptoanesthesia in man].

The present study was designed to investigate the effects of neuraleptanesthesia (NLA) and enflurane (Ethane) anesthesia on plasma levels of growth hormone (GH) and prolactin (PRL) in man. A total of 18 patients aged between 20 and 65 years scheduled for elective open-heart surgery were divided in two groups. In the first group (9 patients) general anaesthesia was induced with sodium thiopental (TPS) (3-5 mg/kg) and was maintained with enflurane administered with an inspired concentration of 1.5% in nitrous oxide (2 litres/min) and oxygen (2 litres/min). In the second group (9 patients) anaesthesia was induced with dihydrobenzopyridol (BPS) (0.1-0.2 mg/kg), fentanyl (5-8 gamma/kg) and TPS (3-5 mg/kg) and was maintained with fentanyl (0,65 mg in average). The patients had neither hepatic, renal or endocrine disease nor did they have a history of steroid therapy. All subjects received atropine (0.01 mg/kg) and diazepam (0.2 mg/kg) i.m. 2 hours before induction of anaesthesia. Blood samples for GH and PRL was collected before induction of anaesthesia (0) and at 30, 60, 90 and 120 minutes after induction: the 90' sample was taken immediately after sternal incision. The sampling was stopped at the start of the cardiopulmonary by-pass. A significative reduction of GH at 60' and of PRL at 30' was observed in both groups. Surgical stress at 90' does not evoke a significant increase of PRL and GH levels in both groups. In conclusion NLA and enflurane induced a decrease of GH and PRL plasma levels; in both groups the anaesthetic agents, at the dosage used during anaesthesia, blocked the response of these hormones to the surgical stress likely due to a block of the hypothalamic-pituitary response.

Adult↗

[Gastroenterologic aspects of connective tissue diseases].

The connective tissue disorders are a protean group of acquired diseases which have in common widespread immunologic and inflammatory alterations of connective tissue. The acquired connective tissue diseases generally include the following clinical entities: rheumatoid arthritis, systemic lupus erythematosus, polymyositis, polyarteritis nodosa, scleroderma, mixed connective tissue disease, Sjögren's and Behcet's sindromes. These entities have certain features in common which include sinovitis, pleuritis, myocarditis, endocarditis, pericarditis, peritonitis, vasculitis, myositis, changes in skin, alteration of connective tissue and nephritis. Gastrointestinal and hepatic involvement in connective tissue disorders are not the most important features, nevertheless appear almost regularly. Anorexia, nausea, vomiting, abdominal pain, malabsorption may affect patients suffering by rheumatoid arthritis, systemic lupus erythematosus and other collagenophaties. In some cases mesenteric vasculitis may cause intestinal ischemia which may result in bowel infarction, mucosal ulceration, hemorrhage, perforation. After an extensive review of the existing literature the Authors make an accurate evaluation of gastrointestinal and hepatic alterations in connective tissue diseases.

Arthritis, Rheumatoid↗

Thrombosis, recurrent abortions and intrauterine foetal death in a patient with lupus anticoagulant.

The authors describe a case report of a patient suffering from thrombosis and recurrent abortions. Routine coagulation screening was abnormal and investigation showed the presence of a circulating anticoagulant. High titres of anticardiolipin antibodies were demonstrated. Antinuclear antibodies were slightly positive and antinative DNA antibodies were present. Lupus anticoagulant activity and anticardiolipin antibodies seem to be strong markers of a thrombotic tendency.

Abortion, Spontaneous↗

[Serum bile acids in dyslipidemic patients].

The sensitivity of total serum bile acid concentration as an index of hepatic damage has long been recognised. In addition serum bile acid measurement is significantly more specific than conventional hepatic function tests. However the concentration might be affected by factors other than hepatic dysfunction. Several authors have reported variations in the synthesis of serum bile acids in dyslipidaemic patients. This might potentially reduce the value of concentration measurement in the diagnosis of hepatic diseases especially considering the relative prevalence of hyperlipidaemia. The present article reports on radioimmunological serum bile acid measurement before and after meals in 10 patients with dyslipidaemia and in 22 controls. No difference was revealed between the two groups. Therefore dyslipidaemia appears not to affect the specificity of the test nor does it invalidate the use of radioimmunological measurement of total serum bile acids in the study of hepatic function.

Aged↗

Concentration of serum bile acids as an index of hepatic damage in systemic lupus erythematosus.

The aim of this work is to evaluate the concentration of serum bile acids (SBA) as an index of impaired liver function in systemic lupus erythematosus (SLE) patients versus usual laboratory tests of hepato-biliary system diseases. In patients with SLE the mean fasting SBA concentration was 9.6 +/- 1.4 mumol/L; in normal subjects the concentration was 2.9 +/- 0.6 mumol/L (P less than 0.01). In patients with SLE, mean gamma-glutamyl transpeptidase (GGTP) concentration was 31.5 +/- 5.9 mU/ml versus 10.05 +/- 1.1 mU/ml in controls (P less than 0.01). The bromsulphalein (BSP) excretion test, 45 minutes after injection, was 6.8 +/- 1% in SLE patients versus 2.8 +/- 0.4% in controls (P less than 0.02). No significant difference was found between these two groups of subjects with respect to leucine aminopeptidase (LAP), alkaline phosphatase (AlPh), glutamic-oxalacetic transaminase (SGOT), glutamic-pyruvic transaminase (SGPT), bilirubin serum rates. SBA rate was abnormal in 50% of the SLE patients; GGTP rate and the BSP excretion test were abnormal in 38% and 27% respectively. Our findings show the presence of an actual liver impairment in SLE patients, significantly demonstrated by fasting SBA concentration, GGTP rate and BSP excretion test. Other liver function tests are less useful in evaluating hepatic damage in SLE.

Adolescent↗

Does secretin control insulin secretion?

The effect of secretin on insulin release has been studied in normal subjects after prestimulation with arginine. In order to make a comparison a pulse of glucose with arginine prestimulation was given. A pulse of 1 U/kg b.w. of secretin provokes a secretion of insulin that is weak and brief compared to that provoked by glucose; thus secretin fails to potentiate arginine-induced insulin secretion. Such a result does not support the hypothesis of secretin as the central hormone in the enteroinsular axis.

Adult↗

Amniotic fluid content of glucose, C-peptide and insulin in normal and diabetic pregnancies.

Glucose, C-peptide and insulin concentrations in amniotic fluid were measured in 63 women, 19 of whom had insulin-dependent diabetes. The amniotic fluid glucose concentration was higher in the diabetic (37.4 +/- 4.1) than in the normal women (19.4 +/- 5.1 mg/dl; P less than 0.01). The amniotic fluid insulin concentration was higher in diabetic than non diabetic women (15.9 +/- 3.1 versus 8.9 +/- 2.1 microU/ml; P less than 0.01). The C-peptide concentration was also higher in the amniotic fluid of diabetic women than normal (1.60 +/- 0.66 vs 0.26 +/- 0.15 nmol/l; P less than 0.001). The lecithin/sphingomyelin (L/S) ratio in the amniotic fluid was greater than 2 in 61 mothers; only two diabetic patients had an L/S ratio lower than 2. Five neonates of diabetic mothers were macrosomic and three of these were also hypoglycaemic. A negative correlation was observed in diabetic women between insulin and C-peptide concentrations in the amniotic fluid and Apgar score of the newborn infants both at 1 and 5 minutes; no correlation was found on the contrary with the amniotic glucose. In the prognostic evaluation of the fetus with a diabetic mother one must consider many parameters. Among these more consideration must be given to the levels of C-peptide and insulin in amniotic fluid than to glucose level.

Amniotic Fluid↗

[Arterial hypertension with hypopotassemia and hypochloremic metabolic alkalosis caused by abuse of a nasal spray].

The case of a young woman, using a nasal spray containing corticosteroids, presenting hypertension systodiastolic, hypokalemia and hypochloremic metabolic alkalosis is presented. Clinical findings, similar to hyperfunction of the adrenal cortex, recovered quickly after discontinuation of the drug. The principal causes of hypertension associated with hypokalemia and hypochloremic metabolic alkalosis, are discussed and the importance of nasal spray, containing glucocorticoids and sympathetic agonists, as a cause of high blood pressure syndromes with different clinical expression and of difficult diagnosis is stressed. The importance of systemic absorption of drugs administered by nasal route is also emphasized.

Adolescent↗

[Changes in thyroid hormone metabolism in subjects with liver cirrhosis].

The behaviour of the serum levels of thyroxine (T4), 3,5,3' tri-iodothyronine (T3), TSH and of the free binding sites of the thyroid hormones binding globulins in 23 patients affected by hepatic cirrhosis, is described in function of the severity of the disease. The values obtained have been statistically compared to those of a group of 14 healthy subjects. A decrease of the serum levels of T3 directly related to the severity of the disease has been remarked in the cirrhotic patients, while no significant differences in the serum levels of T4 and TSH and in the number of free binding sites on the thyroid hormones binding globulins have been noted between the two groups.

Adolescent↗

[Hyperosmolar diabetic coma. Case reports and review of the literature].

The physiopathology and clinical picture of hyperosmolar diabetic coma are described, and four personal cases are presented. This form of coma is a rare, but particularly serious complication of diabetes mellitus. Since its prognosis is poor, even when suitable treatment is provided, the greatest possible care should be devoted to preventing its main cause, namely dehydration.

Aged↗

[Somatostatin].

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Adenoma, Islet Cell↗

[Serum gastrin in rheumatoid arthritis].

Since 1973 some Authors reported a high prevalence of raise serum gastrin levels in rheumatoid arthritis. In our study of 37 subjects with classic or defined RA, 29 (78%) had serum gastrin levels significantly higher than controls (mean 156.3% pg/ml versus 58.8 pg/ml) and 8 (22%) had normal levels. Basal acid output (BAO) and maximal acid output (MAO) of all affected patients did not differ from controls. We found no correlation among gastrinaemia, BAO, MAO, inflammation indexes and RA test. According to the normal acid output of our RA patients, hypergastrinaemia should be caused by factors different from hypochlorhydria. It is possible that immunoreactive, but non biologically active, peptides could interfere with RIA of gastrin, or that other factors, such as prostaglandins or antigastrin antibodies, could modify the activity of endogenous hormone.

Adolescent↗