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S Angeletti

Publications and source records attributed to S Angeletti.

At least 19 recordsLinked to original sources
PubMed1999

Autoradiographic analysis of 5-HT2A binding sites in the brain of Sardinian alcohol-preferring and nonpreferring rats.

The density of 5-HT2A binding sites in the brain of Sardinian alcohol-preferring (sP) and nonpreferring (sNP) rats was evaluated, using [3H]ketanserin for quantitative autoradiography. The highest [3H]ketanserin binding levels were found in the anterior olfactory nucleus, prefrontal cortex, medial prefrontal cortex, post-genual anterior cingulate cortex, insular cortex and claustrum. Statistically significant differences between sP and sNP rats were found in prefrontal cortex, medial prefrontal cortex and post-genual anterior cingulate cortex, where sP rats showed about 20% lower [3H]ketanserin binding levels. No significant difference was found in other areas, although some of them showed slightly lower [3H]ketanserin binding density in sP rats. The 5-HT2A receptor agonist, (+/-)-1-(2,5-dimethoxy-4-iodophenyl)-2-amino-propane hydrochloride (DOI), microinjected into the medial prefrontal cortex, induced a lower number of wet dog shakes in sP than in sNP rats. These results indicate a different density of 5-HT2A binding sites, and a different functional regulation of 5-HT2A receptor mechanisms in discrete brain areas of sP, in comparison to sNP rats. These findings, and those showing lower levels of 5-HT in the frontal cortex of sP rats, suggest that altered 5-HT function in fronto-cortical areas could be linked to the genetic predisposition to high voluntary ethanol intake in these rats.

Alcohol Drinking↗
PubMed1999

Use of oligoprobes on amplified DNA in the diagnosis of bacterial meningitis.

An approach based on the 16 S rDNA polymerase chain reaction (16S PCR) and oligoprobe hybridization was applied to 77 cerebrospinal fluid samples submitted to the clinical microbiology laboratory for culture. Broad-range 16S rDNA primers were selected in conserved regions of the gene. Oligoprobes specific for Neisseria meningitidis, Haemophilus influenzae, Streptococcus spp., and Mycobacterium tuberculosis were selected in specific variable regions of the amplified 600 base pairs (bp) in the 16S rDNA. None of the oligoprobes cross hybridized with DNA from the other bacteria or from common contaminants. There were no false-negative results in culture-positive cerebrospinal fluid samples. Ten cases of meningitis caused by bacteria other than the four probes were not identified by any of the four probes. In culture-negative cerebrospinal fluid samples with some abnormal chemical parameters, there were 14 amplicons -- one of Haemophilus influenzae, three of Streptococcus spp., six of Mycobacterium tuberculosis, and four not identified -- while in normal cerebrospinal fluid samples there were no amplicons.

DNA Primers↗
PubMed1999

Conditioned taste aversion induced by ethanol in alcohol-preferring rats: influence of the method of ethanol administration.

A recent study of our group has shown that ethanol evokes conditioned place preference (CPP) in Marchigian Sardinian alcohol-preferring (msP) rats following intragastric (IG) administration by means of an indwelling IG catheter, but not following administration by gavage or by intraperitoneal (IP) injection. The present study evaluated in ethanol-naive msP rats the influence of the method of administration (IG injection by indwelling catheter vs. IP injection) on ethanol-induced conditioned taste aversion (CTA). The dose of 0.35 g/kg of ethanol did not evoke aversion either by IG or by IP administration. Following IG injection, 0.7 g/kg of ethanol, the amount that msP rats voluntarily ingest in a short (2-5 min) drinking episode, did not evoke CTA, and 1.5 g/kg induced a modest CTA. On the other hand, IP injection of 0.7 g/kg of ethanol evoked CTA, and 1.5 g/kg induced a very pronounced CTA. These findings show that the aversive properties of ethanol in msP rats are influenced by the method of administration, and suggest that the IG injection by catheter may reveal more faithfully than the IP injection the motivational properties of amounts of ethanol that alcohol-preferring rats voluntarily ingest.

Alcohol Drinking↗
PubMed1999

High prevalence of atrophic body gastritis in patients with unexplained microcytic and macrocytic anemia: a prospective screening study.

OBJECTIVE: Atrophic body gastritis (ABG) is characterized by atrophy of the gastric body mucosa, hypergastrinemia, and hypo/achlorhydria. Its association with pernicious anemia is well recognized. Gastric hypo/achlorhydria is known to affect iron absorption but ABG is rarely considered as a possible cause of iron deficiency (microcytic) anemia. The aims of this study were to validate a screening methodology for the detection of ABG in a consecutive series of patients with microcytic and macrocytic anemia and to investigate the clinical and gastric morphofunctional characteristics of the two hematological presentations of ABG. METHODS: A two-part prospective study was carried out. Part A aimed to validate the screening methodology to detect the presence of ABG in patients with macrocytic and microcytic anemia who have no specific GI symptoms, by measuring their gastrin levels and verified by performing gastroscopy with biopsy. Part B aimed to detect the presence of ABG in a larger sample of anemic patients by our validated method and, by pooling the data of ABG patients, to determine the clinical, gastric histological, and functional characteristics pertaining to the macrocytic and microcytic presentations of ABG. RESULTS: In part A, ABG was detected in 37.5% of patients with macrocytic and in 19.5% of those with microcytic anemia. Pooling the data of the ABG patients from part A and part B, microcytic ABG patients were on average 20 yr younger than those with macrocytic anemia. The majority of microcytic ABG patients were female, most of whom were premenopausal. H. pylori infection was widely represented in the microcytic ABG group (61.1%). They also had a lesser grade of body mucosal atrophy and lower hypergastrinemia levels, suggesting a less severe oxyntic damage of shorter duration. CONCLUSIONS: Macrocytic anemia is not the only hematological presentation of ABG. Physicians evaluating patients with unexplained iron deficiency anemia should consider ABG as a possible cause by determining fasting gastrin levels and performing gastroscopy with biopsies of the body mucosa.

Adult↗
PubMed1999

Natural history of intestinal carcinoids.

Historically, carcinoids are a morphologically distinct class of rare intestinal tumours that behave less aggressively than the more common intestinal adenocarcinomas. Some authors restrict the term carcinoid to intestinal endocrine tumours, and others include a large variety of neuroendocrine tumours. Within the gastrointestinal tract, carcinoids are most commonly found in the appendix, followed by the distal small bowel, rectum and stomach. In the vast majority of cases, the carcinoid syndrome is associated with carcinoid tumours of the small intestine that have metastasised to the liver. Episodic flushing and diarrhoea are the most common initial symptoms. Metastatic disease may require no treatment for months or even years in the patient whose symptoms are not seriously interfering with quality of life and if the tumour is not exhibiting a biologically aggressive growth pattern.

Carcinoid Tumor↗
PubMed1998

Mechanism of action for reduction of ethanol intake in rats by the tachykinin NK-3 receptor agonist aminosenktide.

Intracerebroventricular (i.c.v.) injection of tachykinin (TK) NK-3 receptor agonists inhibits alcohol intake in genetically selected alcohol-preferring rats. The present study investigated the mechanism of action by which the selective TK NK-3 receptor agonist aminosenktide (NH2-SENK) attenuates ethanol intake in Marchigian Sardinian alcohol-preferring (msP) rats. The effect of NH2-SENK was studied by i.c.v. injection in the conditioned taste aversion (CTA) and in the conditioned place preference (CPP) paradigms; moreover, the effect of NH2-SENK on blood alcohol levels (BAL) following intragastric ethanol administration was investigated. The i.c.v. dose of 125 ng/rat of NH2-SENK, that markedly reduces ethanol intake, did not modify BAL, nor did it increase the CTA induced by intraperitoneal injection of ethanol, 1 g/kg body weight. These findings suggest that the effect of NH2-SENK on alcohol consumption is not related to modification of the pharmacokinetics of ethanol, nor to increase of the aversive properties of ethanol. On the other hand, the same i.c.v. dose of NH2-SENK evoked a pronounced and statistically significant CPP. This finding indicates that the TK NK-3 receptor agonist NH2-SENK possesses rewarding properties in msP rats and suggests that its inhibitory effect on ethanol consumption may be due to substitution of the rewarding properties of ethanol, thus making its consumption redundant.

Alcohol Drinking↗
PubMed1998

Preprotachykinin-A gene expression in the forebrain of Sardinian alcohol-preferring and -nonpreferring rats.

Increasing evidence suggests that TKergic mechanisms might play a role in ethanol intake control. Preprotachykinin-A (PPT-A) mRNA brain levels were measured in Sardinian alcohol-preferring (sP) and Sardinian alcohol-nonpreferring (sNP) rats. PPT-A mRNAs were about 50% lower in sP than in sNP rats in the bed nucleus of the stria terminalis (BNST), whereas levels in the olfactory tubercle (Tu) were about 30% higher in sP than in sNP rats. Our findings suggest that altered PPT-A gene expression might contribute to the different ethanol preference and intake of sP opposite to sNP rats.

Alcohol Drinking↗
PubMed1998

Sensitivity of brain sites to the inhibitory effect on alcohol intake of the tachykinin aminosenktide.

The present study evaluated the sensitivity of several brain sites to the inhibitory effect of the tachykinin (TK) NK-3 receptor agonist aminosenktide (NH2-SENK) on 10% ethanol intake in genetically selected Marchigian Sardinian alcohol-preferring rats. Attention was focused on limbic structures involved in alcohol-seeking behavior and endowed with TK NK-3 receptors. NH2-SENK was bilaterally injected into the shell of the nucleus accumbens (NACC), the medial amygdala (AMY), the dorsal hippocampus (HIPP), the ventral tegmental area (VTA), the bed nucleus of the stria terminalis (BNST), the lateral hypothalamus (LH), and the nucleus basalis magnocellularis (NBM). NH2-SENK (injected up to 25-75 ng/site) into the NACC, AMY, HIPP, and VTA did not significantly modify ethanol intake. Injection of NH2-SENK into the BNST reduced ethanol intake at doses of 25 ng/site or higher, but the same doses also reduced water intake in water-deprived rats and food intake in food-deprived rats. Injection of NH2-SENK into the LH or the NBM at doses of 0.5, 5, or 25 ng/site inhibited 10% ethanol intake even at the lowest dose tested without affecting either food or water consumption in deprived animals. Present results indicate that the LH and the NBM are highly sensitive to the inhibitory effect of the TK NK-3 receptor agonist NH2-SENK on ethanol intake. TK peptides have been shown to evoke conditioned place preference following injection in the LH or the NBM, suggesting that in these brain sites the effect of TK agonists on ethanol intake might be due to interference with reward processes.

Alcohol Drinking↗
PubMed1998

Relationship between fundic endocrine cells and gastric acid secretion in hypersecretory duodenal ulcer diseases.

BACKGROUND: Acid hypersecretion is associated with duodenal ulcer disease in the following conditions: Zollinger-Ellison syndrome (ZES) and antral gastrin cell hyperfunction (AGCH) due to hypergastrinaemia, or hypersecretory duodenal ulcer (HDU) without hypergastrinaemia. AIM: To evaluate whether quantitative changes in fundic ECL and D cells may be involved in acid hypersecretion. PATIENTS AND METHODS: Seven ZES, six AGCH and six HDU Helicobacter pylori-positive patients were compared. Basal (BAO) and pentagastrin-stimulated gastric acid secretions (PAO), and morphometry of fundic ECL and D cells were performed. The six AGCH and six HDU patients were investigated again using the same tests 1 year after H. pylori eradication. RESULTS: Median PAO values were no different in all the hypersecretory conditions studied. The median volume density of ECL cells in ZES was significantly higher than in controls (2.75, range 1.74-5.8 vs. 0.73, 0.52-1.11: P < 0.05), whereas it was in the control range in AGCH and HDU patients (0.77, range 0.20-1.39 and 0.99, range 0.42-1.51; respectively). The count of fundic D cells was significantly lower in AGCH patients than in all other investigated groups (median 0.16, range 0.1-0.52; P < 0.05). Cure of infection in AGCH and HDU patients did not modify the ECL cell volume density, whereas a significant increase in the count of fundic D cells was observed in AGCH patients. Thus, the ECL/D cell index was significantly affected in AGCH patients (P < 0.05), being higher during H. pylori infection (median 6, range 0.7-9.25) than after the cure (median 2.12, range 1.10-3.5). BAO and PAO were not affected by H. pylori eradication in either group. CONCLUSIONS: The study provides evidence, for the first time, that quantitative alterations in the fundic endocrine cells are not involved in acid hypersecretion of patients with hypersecretory states, and that eradication of H. pylori does not restore normal acid secretion values.

Adult↗
PubMed1998

Serum-mediated enhancement of TNF-alpha release by human monocytes stimulated with the yeast form of Candida albicans.

The role of serum in the production of tumor necrosis factor-alpha (TNF-alpha) by human monocytes stimulated with yeast-form Candida albicans was studied. Pre-exposure of C. albicans to human pooled serum enhanced both TNF-alpha mRNA and cytokine secretion compared with C. albicans preincubated with medium only. Serum factors involved were >30 kDa, were efficiently inhibited by D-mannose, and recognized both Ca++-dependent and -independent pathways. Preincubation of yeasts with rabbit mannose-binding protein (MBP) resulted in dose-related enhancement of TNF-alpha secretion, through a Ca++-dependent pathway inhibited by D-mannose. TNF-alpha levels were similarly induced in C. albicans preincubated with vitronectin and with serum. Ca++ depletion did not affect cytokine release, while D-mannose supplementation displayed inhibition. The latter effect was abolished after Ca++ depletion. These data call for an involvement of both MBP and vitronectin in the serum-mediated enhancement of TNF-alpha release upon stimulation of monocytes with yeast forms of C. albicans.

Animals↗
PubMed1998

Use of the somatostatin analogue octreotide to localise and manage somatostatin-producing tumours.

BACKGROUND: Somatostatin receptor scintigraphy (SRS) and octreotide therapy have both changed the management of gastroenteropancreatic endocrine tumours, but very few data are available on the use of SRS and octreotide to visualise and treat somatostatinomas. METHOD: The results of SRS and octreotide treatment in three somatostatinoma patients were examined. RESULTS: SRS was able to detect extensive hepatic involvement in patient 1, one hepatic and one pancreatic lesion in patient 2, and one hepatic lesion in patient 3. Octreotide therapy (0.5 mg/day subcutaneously) was effective in decreasing plasma levels of somatostatin in all three patients. Symptoms (diabetes and diarrhoea) were greatly improved in the two patients with "somatostatinoma syndrome". CONCLUSION: The study shows that somatostatinoma, like most other gastroenteropancreatic endocrine tumours, possesses functioning somatostatin receptors.

Aged↗
PubMed1998

How to develop good media relations.

One of the aims of this paper is to avoid giving readers a headache! People suffering from headache are generally not easy to deal with, and headache can affect a wide range of people from infants to the elderly. Furthermore, each patient experiences the same pathology in a different way. How can we cope with these difficulties?

Adolescent↗
PubMed1997

In situ hybridization analysis of preprotachykinin-A and -B mRNA levels in short-term sodium depletion.

Tachykinins inhibit salt appetite when applied intracranially in a number of brain regions and may function as endogenous inhibitors of sodium intake. To test the hypothesis that induced increases in salt appetite might involve disinhibition via a reduction in endogenous tachykinin expression, we used a semi-quantitative in situ hybridization analysis to investigate changes in brain areas expressing preprotachykinin-A (PPT-A) and preprotachykinin-B (PPT-B) mRNAs of rats after 1 day of sodium depletion (1d Na dep). PPT-A mRNA levels were detected in neurons of the olfactory tubercle (Tu), the nucleus of the olfactory tubercle (LOT), the dorsal and ventral caudate-putamen (d-CPu and v-CPu), the bed nucleus of the stria terminalis (BNST), the medial preoptic area (mPOA), the habenula (Hb) and the postero-dorsal part of the amygdala (MePD). PPT-B mRNA levels were measured in fundus striati (FStr), d-CPu, v-CPu, BNST, mPOA, dorsomedial hypothalamic nucleus (DMD), arcuate nucleus (Arc), central amygdaloid nucleus (CeL), basolateral amygdaloid nucleus (BLV), LOT, Hb and basal nucleus of Meynert (B). 1d Na dep reduced by 33-61% the mean number of PPT-A grains/cell in Tu, LOT, d-CPu, BNST, mPOA, Hb and MePD compared to control animals. Levels of PPT-B mRNA were not reduced as much by 1d Na dep, although statistically significant reductions of 26, 34 and 17% were found in v-CPu, BNST and B, respectively. These findings, therefore, support the hypothesis that endogenous tachykinins exert an inhibitory influence over sodium appetite.

Animals↗
PubMed1997

Monitoring for cytomegalovirus infection in organ transplant recipients: analysis of pp65 antigen, DNA and late mRNA in peripheral blood leukocytes.

The use of sensitive and specific methods for rapid and reliable diagnosis is required due to the considerable impact of human cytomegalovirus (HCMV) in organ transplant recipients. For this purpose the demonstration of the presence of viral antigens in peripheral blood leukocytes (PMNLs) and of viral nucleic acids in the same cells or in sera would seem to be of valid support. The present study was designed to test pp65 antigen, HCMV DNA and HCMV late mRNA in order to provide clinical information for the management of the infection. Fifty solid organ recipients were monitored for six months after transplant. The data obtained from the various tests were analysed from the first evidence of HCMV infection revealed by positive antigenaemia and/or DNA-polymerase chain reaction (PCR). In 3 asymptomatic and in 7 symptomatic patients, PCR became positive 1-2 weeks before antigenaemia but PCR did not discriminate the clinical evolution of HCMV infection. The antigenaemia test well correlated to the development of viral infection being positive in all symptomatics and in 31, 2% of asymptomatics. The antigenic load > 100/2 x 10(5) positive cells was always associated with clinical signs of illness. The detection of late mRNA was more indicative of the virus replicative status in the follow-up of patients treated with ganciclovir. In some cases there was evidence, prior to the other two tests, the block of viral replication due to the antiviral therapy and in others the onset of HCMV infection relapse.

Antigens, Viral↗
PubMed1997

Regulation of preprotachykinin-A mRNA in genetic hypertensive and normotensive rats.

It is well-known that central administration of tachykinins (Tks) inhibit salt intake in rats. Recent studies have shown that conditions that arouse salt appetite, such as adrenalectomy and sodium depletion, induce a decrease in preprotachykinin-A (PPT-A) mRNA in discrete regions of the rat brain, suggesting that reduced levels of PPT-A mRNA in the brain may have a permissive role on the expression of salt appetite. It has also been shown that spontaneously hypertensive rats (SHR) show higher avidity for salty solutions than their normotensive control Wistar-Kyoto (WKY) rats. In this regard, the present study tested whether SHR and WKY rats differ in expression of the gene coding for PPT-A, the precursor for Tks peptides. Using semi-quantitative in situ hybridization histochemistry, we examined the level of PPT-A mRNA in discrete rat brain regions of SHR and WKY rats under no treatment, after 1 or 3 days of Na+ depletion. Levels of PPT-A mRNA were analysed in the olfactory tubercle (Tu), in the lateral olfactory tubercle (LOT), in the dorsal and ventral caudate putamen (d/v CPu), in the medial preoptic area (mPOA), in the bed nucleus of the stria terminalis (BNST), in the habenula (Hb) and in the postero-dorsal part of the amygdala (MePD). Semi-quantitative analysis of silver grains revealed a 27.5% lower expression of the PPT-A mRNA levels in SHR opposite to WKY rats under no treatment in v-CPu, mPOA, BNST and Hb. 1 day of Na+ depletion reduced PPT-A mRNA levels when opposite to Na+-repleted animals in Tu and mPOA in both SHR and WKY rats. On the other hand, when comparing SHR and WKY rats after 1 day of Na+ depletion, a 26% lower level of PPT-A mRNA was detected in Tu and d-CPu of SHR opposite to WKY rats whereas a 14% and an 18% lower level was detected in v-CPu and Hb, respectively. A lower expression of PPT-A mRNA in SHR compared to WKY rats was also found in BNST and MePD, although no statistical significance was detected in these two brain areas. In the last experiment, 3 days of Na+ depletion reduced PPT-A mRNA levels in mPOA while negligibly increased mRNA levels in d-CPu and v-CPu, in BNST, Hb and MePD, both in SHR and WKY rats. Conversely, when making comparisons between the two strains, a 35% lower level of PPT-A mRNA in SHR with respect to WKY rats was found after 3 days of Na+ depletion in d-CPu, v-CPu and mPOA. A lower gene expression, even though not statistically significant, was found in Tu, LOT, MePD. These findings show a consistent difference of PPT-A mRNA levels in discrete regions of the SHR brain opposite to WKY rats and confirm that 1 day of Na+ depletion reduces PPT-A mRNA in discrete brain regions. Since SHR are notoriously more salt-avid than WKY rats and Tks are potent inhibitors of sodium intake, the down-regulation of PPT-A mRNA may contribute to the higher natriophilia and, therefore, to the etiology of the hypertensive disease.

Animals↗
PubMed1997

Reversal of long-standing iron deficiency anaemia after eradication of Helicobacter pylori infection.

Helicobacter pylori has been proposed as a major determinant in multiple gastric disorders. We describe the case of a young adult with a long-standing medical history of sideropenic anaemia and of oral iron consumption dependence with a chronic superficial H. pylori-positive gastritis. All other causes of sideropenic anaemia were carefully excluded. Histology showed a peculiar pattern of non-active H. pylori-positive gastritis. The bacterium was a non-VacA-producing strain. The first attempt at eradication caused a reduction in bacterial load and led to a partial normalization of haematologic variables without improving the ferritin level. A successful second course of eradication therapy completely reversed the anaemia and restored the iron deposit, which persisted at the 29-month follow-up. H. pylori infection can be involved in unexplained cases of iron deficiency anaemia in adults, and its cure can normalize the haematologic picture.

Adult↗
PubMed1996

Somatostatin receptor localization of pancreatic endocrine tumors.

Gastroenteropancreatic endocrine tumors are difficult to localize. At the same time the tumor is localized, though, there is an opportunity for cure or to remove tumor tissue. In this study we have prospectively examined the ability of 111In-octreotide scintigraphy, magnetic resonance imaging (MRI), and computed tomography (CT) to localize tumor lesions in 24 patients with a biochemical or histologic diagnosis of neuroendocrine tumor. In eight patients a surgical assessment of the imaging results was prospectively performed. Planar and abdominal single-photon emission tomography (SPET) images acquired 4 and 24 hours after 180 to 220 MBq of 111In-octreotide injection were evaluated and compared with conventional imaging techniques. SPET scintigraphy visualized more presumed tumor lesions (n = 39) than conventional imaging studies (MRI,n = 25; CT,n = 13); 23 of 24 patients had positive octreotide scintigraphy, 17 of 24 had positive MRI-scans, and 12 of 24 patients had positive CT scans. It was concluded that 111In-octreotide scintigraphy combined with conventional imaging improves the preoperative localization of presumably tumorous lesions in patients with gastroenterohepatic endocrine tumors.

Adenoma, Islet Cell↗