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R Corinaldesi

Publications and source records attributed to R Corinaldesi.

At least 55 records · Page 3Linked to original sources
PubMed2001

Review article: Helicobacter pylori, mucosal inflammation and symptom perception--new insights into an old hypothesis.

The role of Helicobacter pylori and the accompanying mucosal inflammatory response in functional dyspepsia is still undefined. Human and animal studies have clearly demonstrated a link between intestinal mucosal inflammation and changes in sensory-motor function. Growing clinical and basic evidence supports the concept that a similar paradigm may occur in H. pylori-related dyspepsia. The infection may both induce gastric dysmotility and trigger neuroplastic changes in the afferent neural pathways leading to visceral hyperalgesia. A reduction of central antinociceptive control systems may also play a pathophysiological role. H. pylori eradication has provided disappointing results in terms of improvement of symptoms. This may reflect the long-term recovery of neuroplastic changes occurring in the afferent nervous system or, alternatively, the incomplete resolution of gastritis and the persistent production of inflammatory mediators by resident cells in the muscularis externa. The identification of these mechanisms may provide a better understanding of the pathophysiology of H. pylori-related dyspepsia and prompt innovative therapeutic approaches.

Animals↗
PubMed2001

Review article: the pharmacological treatment of acute colonic pseudo-obstruction.

Acute colonic pseudo-obstruction (Ogilvie's syndrome) can be defined as a clinical condition with symptoms, signs and radiological appearance of acute large bowel obstruction unrelated to any mechanical cause. Recent reports of the efficacy of cholinesterase inhibitors in relieving acute colonic pseudo-obstruction have fuelled interest in the pharmacological treatment of this condition. The aim of the present review is to outline current perspectives in the pharmacological treatment of patients with acute colonic pseudo-obstruction. The best documented pharmacological treatment of Ogilvie's syndrome is intravenous neostigmine (2-2.5 mg), which leads to quick decompression in a significant proportion of patients after a single infusion. However, the search for new colokinetic agents for the treatment of lower gut motor disorders has made available a number of drugs that may also be therapeutic options for Ogilvie's syndrome. Among these agents, the potential of 5-hydroxytryptamine-4 receptor agonists and motilin receptor agonists is discussed.

Acute Disease↗
PubMed2001

Tachykinin-dependent and -independent components of peristalsis in the guinea pig isolated distal colon.

BACKGROUND & AIMS: In the intestine, tachykinins regulate motility by participating in neuromuscular and neuro-neuronal transmission. The aim of this study was to test the hypothesis that colonic propulsion is regulated by an interplay between tachykinergic and cholinergic transmission. METHODS: Propulsion was elicited by intraluminal distention of a thin rubber balloon, which traveled from the oral to the anal end of guinea pig isolated distal colon segments. The overall contribution of endogenous tachykinins to colonic propulsion was examined by blocking NK1, NK2, and NK3 receptors simultaneously. RESULTS: NK2-receptor blockade by MEN 11420 inhibited propulsion, whereas blockade of NK(1) by SR 140333 or of NK3 receptors by SR 142801 had minor effects on motility. Blockade of muscarinic or nicotinic receptors by hyoscine or hexamethonium decelerated peristalsis up to propulsion arrest. In the presence of partial muscarinic receptor blockade, the NK1-receptor antagonist SR 140333 and the NK2-receptor antagonist MEN 11420 markedly inhibited propulsion. Propulsion was also inhibited by the NK3-receptor antagonist SR 142801 in the presence of partial nicotinic receptor blockade. The simultaneous administration of the 3 tachykinin antagonists inhibited propulsion by 50%. CONCLUSIONS: This study demonstrates the existence of an interplay between tachykinergic and cholinergic pathways during peristalsis and the importance of endogenous tachykinins acting at multiple receptor sites in the control of colonic propulsion.

Animals↗
PubMed2001

Epidemiology, clinical features and diagnosis of gastroenteropancreatic endocrine tumours.

Gastroenteropancreatic (GEP) neoplasms originate from any of the various cell types belonging to the neuroendocrine system. A general characteristic of GEP endocrine tumours is that the vast majority produce and secrete a multitude of peptide hormones and amines. Many patients with malignant metastasising tumours present clinical symptoms related to hormone hyperproduction. These include the so-called carcinoid syndrome, characterised by flushing, diarrhoea, wheezing and right heart disease, which is predominantly associated with the serotonin- and tachykinins-producing carcinoids of the midgut. Several types of syndrome associated with GEP endocrine tumors are caused by overproduction of a specific hormone. For instance, the well-known Zollinger-Ellison syndrome is gastrin-mediated. The so-called 'insulinoma syndrome' depends on excessive production of insulin and proinsulin, resulting in hypoglycemia. The 'glucagonoma syndrome' is characterised by necrolytic migratory erythema, diabetes and diarrhoea. The Verner-Morrison syndrome, which is brought about by high circulating levels of vasointestinal peptide (VIP). produces severe secretory diarrhoea. Finally the 'somatostatinoma syndrome' involves gallbladder dysfunction and gallstones, diarrhoea with or without steatorrhea, and impaired glucose tolerance. The biochemical diagnosis of endocrine digestive tumors is based on general and specific markers. The best general markers are chromogranin A (CgA) and pancreatic polypeptide (PP). Specific markers for endocrine tumors include insulin, gastrin, glucagon, vaso intestinal polypeptide (VIP), somatostatin and the primary cathabolic product of serotonin, 5-hydroxyndoleacetic acid (5-HIAA). Localisation procedures commonly applied, in the diagnosis of endocrine tumours include ultrasound (US), computed tomography (CT) and somatostatin receptor scintigraphy (SRS).

Biomarkers, Tumor↗
PubMed2001

Diagnostic value of plasma chromogranin A in neuroendocrine tumours.

AIM: The aim of this study was to assess the value of plasma chromogranin A (CgA), a protein produced by neuroendocrine cells, in the diagnosis of neuroendocrine tumours. METHODS: Eighty subjects with neuroendocrine tumours were studied. Thirty-four had carcinoids, 21 nonfunctioning endocrine pancreatic tumours, 17 multiple endocrine neoplasia type 1 (MEN 1) (six of these also had gastrinomas), and eight had functioning pancreatic tumours (four gastrinomas, two glucagonomas, two somatostatinomas). Twenty-eight healthy subjects were studied as controls. A fasting plasma sample was obtained from each subject, and CgA plasma levels were measured by the ELISA method using a kit (Dako A/S, Denmark). RESULTS: In control subjects, plasma CgA values were below 5 U/l. Among the patients, 20 of the 34 with carcinoid tumours, 12 of the 21 with nonfunctioning pancreatic tumours, nine of the 17 with MEN 1 (including the six with gastrinomas), and the four gastrinomas of the eight functioning pancreatic tumours, i.e. overall, 45 of the 80 patients (56.3%) had abnormally high CgA values (22-961 U/l). Most of the patients with elevated CgA values, except nine of the 10 with gastrinomas, had multiple liver metastasis. CONCLUSIONS: The results show that the diagnostic value of plasma CgA in neuroendocrine tumours is relatively low; it may be of some interest only in patients with advanced disease and liver metastasis. Gastrinoma seems to be an exception, because in this tumour high CgA values are generally found even in the absence of liver metastasis.

Adult↗
PubMed2001

Intestinal inflammation and activation of sensory nerve pathways: a functional and morphological study in the nematode infected rat.

BACKGROUND: In the rat, gastric distension elicits an intensity dependent pseudoaffective bradycardia mediated via capsaicin sensitive afferent and cholinergic efferent vagal pathways. Inflammation alters visceral perception although the mediators responsible have not been identified. In the nematode infected rat, there is a substantial increase in neuronal substance P (SP) content of the gut. AIMS: To examine the effects of inflammation on perception of a noxious visceral stimulus and on SP and neurokinin 1 (NK-1) receptor immunoreactivity (IR) in visceral afferent pathways. METHODS: Immunohistochemistry was performed on sections from the jejunum, dorsal root ganglia (DRG), and spinal cord (T1-L1) using SP and NK-1 rabbit polyclonal antibodies. In the DRG, the number of SP-IR or NK-1-IR neurones per section was visually quantified. The pseudoaffective cardiac reflex response to gastric stimulation was compared in control and Trichinella spiralis infected rats. RESULTS: Intestinal inflammation induced a rightward shift in the intensity dependent bradycardic response to gastric distension. This was associated with a marked increase in SP-IR not only in the gut wall but also in the DRG and dorsal horn of the spine. In contrast, NK-1-IR was not increased in the gut wall. Moreover, inflammation evoked a decrease in NK-1-IR in the dorsal horn. No NK-1-IR was identified in the DRG of either control or infected animals. CONCLUSIONS: Intestinal inflammation modulates the capsaicin sensitive pseudoaffective autonomic response to gastric distension, increases SP-IR in afferent pathways, and downregulates dorsal horn NK-1-IR. As the pseudoaffective response is capsaicin sensitive, the rightward shift of the response is likely the consequence of the decrease in NK-1 receptors in the sensory pathways.

Animals↗
PubMed2000

Gastric emptying and dyspeptic symptoms in patients with nonautoimmune fundic atrophic gastritis.

Our aim was to evaluate the relationship between gastric emptying and demographic, clinical, histological, and secretory features in patients with nonautoimmune fundic atrophic gastritis. Only 31% of 45 patients with fundic atrophic gastritis presented with achlorhydria. Scintigraphic gastric emptying of solids was delayed compared to healthy controls. Patients with achlorhydria showed gastric emptying rates lower than those with preserved acid secretion. Significant, but weak, correlations were observed between emptying rates and both peak acid output (Rs = 0.33) and serum gastrin levels (Rs = -0.36), but not with grading of mucosal atrophy. No symptom differences were observed between patients with or without achlorhydria, but a weak correlation was detected between peak acid output and the severity of epigastric pain (Rs = 0.40). In conclusion, patients with fundic atrophic gastritis present delayed gastric emptying that is weakly related to the reduction of the acid secretion and the raising of serum gastrin levels rather than to the severity of the atrophy.

Achlorhydria↗
PubMed2000

Role of nitric oxide- and vasoactive intestinal polypeptide-containing neurones in human gastric fundus strip relaxations.

The morphological pattern and motor correlates of nitric oxide (NO) and vasoactive intestinal polypeptide (VIP) innervation in the human isolated gastric fundus was explored. By using the nicotinamide adenine dinucleotide phosphate hydrogen (NADPH)-diaphorase and specific rabbit polyclonal NO-synthase (NOS) and VIP antisera, NOS- and VIP-containing varicose nerve fibres were identified throughout the muscle layer or wrapping ganglion cell bodies of the myenteric plexus. NOS-immunoreactive (IR) neural cell bodies were more abundant than those positive for VIP-IR. The majority of myenteric neurones containing VIP coexpressed NADPH-diaphorase. Electrical stimulation of fundus strips caused frequency-dependent NANC relaxations. N(G)-nitro-L-arginine (L-NOARG: 300 microM) enhanced the basal tone, abolished relaxations to 0.3 - 3 Hz (5 s) and those to 1 Hz (5 min), markedly reduced ( approximately 50%) those elicited by 10 - 50 Hz, and unmasked or potentiated excitatory cholinergic responses at frequencies > or =1 Hz. L-NOARG-resistant relaxations were virtually abolished by VIP (100 nM) desensitization at all frequencies. Relaxations to graded low mechanical distension (< or =1 g) were insensitive to tetrodotoxin (TTX: 1 microM) and L-NOARG (300 microM), while those to higher distensions (2 g) were slightly inhibited by both agents to the same extent ( approximately 25%). In the human gastric fundus, NOS- and VIP immunoreactivities are colocalized in the majority of myenteric neurones. NO and VIP mediate electrically evoked relaxations: low frequency stimulation, irrespective of the duration, caused NO release only, whereas shortlasting stimulation at high frequencies induced NO and VIP release. Relaxations to graded mechanical distension were mostly due to passive viscoelastic properties, with a slight NO-mediated neurogenic component at 2 g distension. The difference between NO and VIP release suggests that in human fundus accommodation is initiated by NO. British Journal of Pharmacology (2000) 129, 12 - 20

Aged↗
PubMed2000

Review article: the continuing dilemma of dyspepsia.

Dyspepsia drains a substantial proportion of healthcare resources in industrialized countries and an appropriate management strategy is needed. An aetiological role for Helicobacter pylori infection has been demonstrated in a number of pathological conditions associated with dyspepsia, such as peptic ulcer and gastric malignancies, but not in functional dyspepsia. Endoscopy and diagnosis-based treatment, H. pylori testing and eradication therapy, history taking and empirical therapy, are the main tools that are currently available for managing patients with upper gastrointestinal symptoms. Endoscopy identifies malignancies and organic diseases of the proximal gut and therefore provides reassurance to both doctors and patients. It should be recommended in older patients with suspicious symptoms and it has proven to be more cost-effective than empirical H2-receptor antagonists in patients with ulcer-like symptoms. Empirical eradication in all dyspeptics without suspicious symptoms is a cost-effective approach that cures the majority of peptic ulcers. Nevertheless, it does not control symptoms in the majority of patients, it may exacerbate gastro-oesophageal reflux disease, and it encourages antibiotic resistance. The realities of current clinical practice require empirical therapy in most, if not all, the dyspeptics seen by general practitioners. A detailed history taking can help to diagnose gastro-oesophageal reflux disease and to identify suspicious symptoms. Furthermore, identification of dyspepsia subgroups may provide guidance for empirical therapy. Nevertheless, even analysis of individual symptoms does not provide a sufficient diagnostic yield to differentiate functional from organic dyspepsia and appropriate investigations are needed in patients with poor response to short-term therapy or frequent relapses.

Dyspepsia↗
PubMed2000

Treatment of gastroenteropancreatic neuroendocrine tumours with octreotide LAR.

BACKGROUND: Octreotide long acting repeteable (LAR) is a new somatostatin analogue whose activity lasts 28 days. AIM: To assess its therapeutic efficacy, tolerability, and safety in patients with gastroenteropancreatic neuroendocrine tumours. METHODS: A total of 16 patients were studied; 10 patients with carcinoid tumours, three with non-functioning pancreatic tumours, two with Zollinger-Ellison syndrome associated with multiple endocrine neoplasia type 1, and one with glucagonoma were studied. Octreotide LAR was administered intramuscularly at a dose of 20 mg every 28 days for a mean of 10.7 months (range 6-15 months). RESULTS: In carcinoid tumour patients, octreotide LAR normalized bowel movements in nine out of 10 cases, and flushing episodes disappeared in seven out of eight cases. Even in the remaining six patients the symptoms disappeared. In carcinoid tumour patients, urinary 5-hydroxyindoleacetic acid decreased significantly. In the two patients with Zollinger-Ellison syndrome/multiple endocrine neoplasma type 1 and in the patient with glucagonoma, serum gastrin and plasma glucagon, respectively, decreased considerably. Tumour size remained unchanged in 14 out of 16 patients, and increased in the remaining two. No side-effects were observed. CONCLUSIONS: Octreotide LAR appears to have a good therapeutic efficacy, tolerability and safety in the treatment of neuroendocrine tumours. Its effects are similar to those of octreotide and lanreotide. However, because it only needs to be administered once every 28 days, it is preferable in clinical practice.

Adult↗
PubMed2000

Role of antibiotic therapy on long-term germ excretion in faeces and digestive symptoms after Salmonella infection.

BACKGROUND: The role of antibiotic therapy on Salmonella faecal excretion is controversial. Acute Salmonella gastroenteritis induces long-lasting digestive symptoms in up to one-third of subjects. The role of antimicrobial therapy on persistent post-infectious symptoms is unknown. AIM: To investigate the role of antibiotic therapy on long-term germ faecal excretion and digestive symptoms after Salmonella infection. SUBJECTS AND METHODS: 1543 subjects [518 aged between 3 and 5 years (35.3%); 950 between 6 and 10 years (64.7%) and 75 adults (4.9%)] involved in a single outbreak of Salmonella enteritis fulfilled the study criteria by repeating stool cultures and answering a symptom questionnaire 3 months post-infection. RESULTS: 327 subjects (21.2%) were treated with antibiotics during the acute infection [121 children aged 3-5 years (23.4%), 175 children aged 6-10 years (18.4%) and 31 adults (41.3%)]. Antibiotic treatment did not affect Salmonella excretion at any of the time points studied up to three months post-infection in any age group as compared to age-matched untreated controls. Persistent digestive symptoms were more common among the patients treated with antibiotics (9.5% vs. 2.9%; P=0.003). CONCLUSIONS: Antibiotic therapy does not affect Salmonella enteritis excretion. Digestive symptoms after clearance of the infectious agent are significantly higher in patients treated with antibiotics during acute gastroenteritis.

Adult↗
PubMed2000

Idiopathic myenteric ganglionitis underlying intractable vomiting in a young adult.

Inflammatory infiltration of intestinal myenteric plexuses (i.e. myenteric ganglionitis), along with severe intestinal motor abnormalities, may accompany paraneoplastic syndromes, neurological disorders and gastrointestinal infections, although rare cases can be idiopathic. In this report, we describe the case of a patient who presented with chronic intractable vomiting and weight loss associated with idiopathic myenteric ganglionitis mainly involving the stomach. Tissue analysis showed that the inflammatory infiltrate comprised T lymphocytes (CD4+ and CD8+), and peptide immunolabelling revealed a marked decrease of substance P/tachykinin immunoreactive staining in nerve fibres and myenteric neurones. Following systemic steroid therapy, the patient's symptoms dramatically improved, and after one year of follow-up his general condition remains satisfactory. The possible mechanisms leading to symptom generation and gastric dysmotility in the context of an idiopathic myenteric ganglionitis are discussed.

Adult↗