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R Corinaldesi

Publications and source records attributed to R Corinaldesi.

At least 73 records · Page 4Linked to original sources
PubMed1999

Anti-CagA reactivity in Helicobacter pylori-negative subjects: a comparison of three different methods.

Emerging evidence suggests that infection by CagA-positive Helicobacter pylori strains is related to the development of more serious gastroduodenal diseases, thus conferring to the determination of anti-CagA antibodies a relevant clinical significance in serological screenings. The detection of anti-CagA positivity in sera negative for anti-H. pylori antibodies raises the question of whether this apparently nonsense result is merely due to a false positive reaction. To address this issue, we compared three different methods for the detection of anti-CagA antibodies. In all, 272 selected sera from patients with precisely defined H. pylori status (positive or negative concordance of five tests, ie, histology by Giemsa in both antrum and corpus, rapid urease test, culture, [13C]urea breath test, IgG ELISA) were tested for anti-CagA reactivity by three different techniques (western immunoblotting, ELISA, and recombinant immunoblotting assay). In order to assess the sensibility and specificity of each tests, we considered as "true" anti-CagA positive sera those with two out of three positive results. Sera from 70% of H. pylori-positive patients and 10% from H. pylori-negative patients turned out to be "true" positives for anti-CagA antibodies. The three methods showed similar excellent results, in terms of both sensitivity and specificity, always over 93%. It is confirmed that a proportion of patients with a negative conventional serology against H. pylori possess anti-CagA antibodies in their sera. In this paper we demonstrate that it can happen even in patients without any biological signs of actual H. pylori infection. The possibility that this can be due to a false positive laboratory result is very likely ruled out by the accuracy of the three methods used. The clinical management of these patients needs further study on larger series.

Adult↗
PubMed1999

Tachykinin NK(1)receptor-mediated inhibitory responses in the guinea-pig small intestine.

We used in vivo, in vitro studies and immunohistochemistry to elucidate the mechanisms activated by tachykinin NK(1)receptors in evoking inhibitory motor response in the guinea-pig small intestine. In vivo, the selective NK(1)receptor agonist GR 73,632 produced a dose-dependent suppression of the distension-induced duodenal contractions, and a decrease of basal tone. These effects were reduced by pretreatment with the NK(1)receptor antagonist SR 140,333. In L-Nomega-nitro-L-arginine methylesther hydrochloride-pretreated animals, the suppressant effect of GR 73,632 on duodenal contractions was reduced, whereas the relaxation of the basal tone was unaffected. In vitro, GR 73,632 evoked a biphasic response consisting of a transient, tetrodotoxin-sensitive inhibitory effect followed by tetrodotoxin-resistant contractions. SR 140,333 blocked both inhibitory and excitatory motor responses induced by GR 73,632. NK(1)immunoreactivity was localized to myenteric and submucosal neurons and to interstitial cells of Cajal in the deep muscular plexus of the small intestine. NK(1)receptor-expressing neurons had Dogiel type I morphology and many of them were beta-nicotinamide adenine phosphate dinucleotide-diaphorase-positive, indicating they are inhibitory neurons. In conclusion, in the guinea-pig small intestine, NK(1)receptor stimulation evokes a myogenic excitatory motor response and a neurogenic inhibitory motor response that involves, at least in part, a nitrinergic pathway.

Adrenergic Agents↗
PubMed1999

Risk indicators of organic diseases in uninvestigated dyspepsia: a one-week survey in 246 Italian endoscopy units.

OBJECTIVE: To evaluate the predictive value of demographic and clinical features and of the results of an office-based test for Helicobacter pylori antibodies, in the presence of organic dyspepsia. DESIGN: Over a 1-week period, 2206 consecutive patients first referred for endoscopy in 246 Italian centres were included. METHODS: Demographic and clinical features, endoscopy findings, and histological diagnosis of H. pylori infection were recorded for all patients. IgG antibodies to H. pylori were determined in 2128 cases by a rapid, immunochromatographic method (Flex Sure HP, S.K.D., San Jose, CA). RESULTS: Endoscopic abnormalities were found in 939 patients (42.6%). Histologically assessed H. pylori infection was predictive for duodenal ulcer (odds ratio (OR), 6.79; 95% confidence interval (CI), 4.4-10.5). Being male (OR, 1.97; 95% CI, 1.7-2.3), older than 40 years (OR, 1.81; 95% CI, 1.5-2.2), a smoker (OR, 1.88; 95% CI, 1.6-2.3), and presenting nocturnal awakening (OR, 1.62; 95% CI, 1.3-2.0) were independently associated with secondary dyspepsia. Epigastric (OR, 1.50; 95% CI, 1.2-1.9) and retrosternal pain (OR, 1.39; 95% CI, 1.1 -1.8) severe enough to affect the usual activities were predictive of organic diseases. The results of the Flex Sure HP test correlated poorly with histological findings. CONCLUSIONS: Male gender, older age, cigarette smoking, a family history of peptic ulcer, symptoms severe enough to induce awakening, epigastric/retrosternal pain severe enough to influence the usual activities are all independently (although weakly) associated with organic dyspepsia. H. pylori infection is strongly associated with duodenal ulcer, but the rapid test we used was not sensitive enough to achieve clinical utility.

Adult↗
PubMed1999

Predominant symptoms identify different subgroups in functional dyspepsia.

OBJECTIVE: Dyspepsia is a common syndrome that often defies diagnosis. Whether the unexplained (or "functional") dyspepsia represents a homogeneous syndrome or includes different subgroups with specific clinical features has not been clarified. The aim of this study was to investigate the relationship between symptom severity, demographic features, and gastric dysmotility in a large series of patients with functional dyspepsia. METHODS: Severity of individual digestive symptoms, demographic features, and scintigraphic gastric emptying of solids were evaluated in 483 patients with chronic unexplained dyspepsia. RESULTS: Two main subgroups were identified. The first was characterized by predominant epigastric pain, male gender (61%), and normal gastric emptying. The second subgroup was characterized by predominant nonpainful symptoms, female gender (60%), a high frequency of associated irritable bowel syndrome (30%), and delayed gastric emptying (42%). A third group included approximately one-third of patients who did not present with any predominant symptom, and was characterized by a high frequency of delayed gastric emptying (30%), overlapping irritable bowel syndrome (28%), and gastroesophageal reflux disease (41%). CONCLUSIONS: Different subgroups exist among patients with functional dyspepsia seen in a referral center. They can be identified by the predominant symptom and are characterized by different demographic, clinical, and pathophysiological features.

Adult↗
PubMed1999

Esophageal and gastric nitric oxide synthesizing innervation in primary achalasia.

OBJECTIVE: We performed a qualitative and quantitative analysis of the nitrinergic neurons in the esophageal and gastric component of the lower esophageal sphincter (LES) and gastric fundus of patients with primary achalasia. METHODS: Four muscle strips were obtained from the esophagogastric junction (two from the esophageal and two from the gastric side of the LES), and two from the gastric fundus of six patients with endstage achalasia who underwent an esophagogastric myotomy plus hemifundoplication. Control specimens were obtained from eight patients who underwent surgery for cancer of the thoracic esophagus. Fixed sections were processed for NADPH-diaphorase histochemistry and the number (mean +/- SE) of nitrinergic neurons per section was visually quantified in each specimen. RESULTS: In the controls, nitric oxide fibers were distributed to the muscle layer and surrounding myenteric neurons of both the LES and the gastric fundus. By contrast, achalasic patients showed a marked decrease of nitric oxide nerves and labeled neurons in both esophageal and gastric components of the LES and the gastric fundus. Quantitative assessment in achalasic patients showed that the mean number of nitrinergic neurons was dramatically reduced in both the esophageal (0.2 +/- 0.1) and the gastric component (2 +/- 0.6) of the LES as compared to those in controls (15 +/- 5 and 12 +/- 4, respectively; p < 0.05); nitrinergic neurons in the gastric fundus (3 +/- 1) were significantly reduced in comparison to those of controls (10 +/- 2) (p < 0.05). CONCLUSIONS: Our results indicate that achalasia is a motor disorder with an intrinsic inhibitory denervation of the esophageal and gastric component of the LES and of the proximal stomach, thus providing further evidence for an extraesophageal extension of the disease.

Adult↗
PubMed1999

How should Helicobacter pylori negative patients be managed?

Dyspepsia is a digestive syndrome distinct from (although frequently overlapping with) gastro-oesophageal reflux disease (GORD) and irritable bowel syndrome (IBS), which is characterised by various combinations of painful and non-painful symptoms arising from the epigastrium. Dyspepsia can be secondary to a variety of diseases, but in most instances it is idiopathic. Helicobacter pylori infection is responsible for the majority of peptic ulcers and of other diseases potentially associated with dyspepsia. Nevertheless, a causal role for H pylori infection in symptom occurrence has not been established. Experimental data indicate that H pylori eradication does not improve symptoms in the majority of dyspeptic patients. It has been proposed recently that H pylori negative patients should be managed according to their clinical presentation. Some reports suggest that taking into consideration the most relevant or "predominant" symptom may help to identify distinct subgroups among dyspeptic patients with different underlying pathophysiological abnormalities and different responses to treatment. Well designed and conducted prospective studies are needed to verify whether treatment of H pylori negative dyspeptic patients based on the predominant symptom actually is a cost effective approach.

Dyspepsia↗
PubMed1999

A histological and immunohistochemical study of neuropeptide containing somatic nerves in the levator ani muscle of women with genitourinary prolapse.

BACKGROUND: To evaluate the changes occurring in the somatic innervation throughout the levator ani muscle in women with genitourinary prolapse and stress urinary incontinence (SUI). METHODS: Thirty-four patients with genital prolapse entered the study and ten subjects with non-malignant pathologies acted as a control group. All patients were evaluated by urodynamic investigation and an electromyographic study of pelvic floor muscles to define the type of urinary incontinence. Biopsy samples were obtained from both groups of patients: the site of muscle biopsies were left and right part of perirectal pubococcygeus muscle. The evaluation of immunoreactivity was semiquantitative and based on staining intensity and distribution. RESULTS: In all cases, S-100 protein and NSE immunoreactivities were found in nerve fascicles running throughout the striated muscle. NPY and VIP positivities were more intense and diffuse, whereas SP immunoreactivity was quite scanty. The different patterns of NPY and VIP expression changed in relation to degree of genital prolapse and to the presence of SUI. CONCLUSIONS: Our immunohistochemical study shows the presence in the pelvic floor of neurons that are able to synthesize neuropeptides. The lower immunoreactivity score of same neuropeptides (VIP, NPY) observed among patients with third degree genital prolapse and with SUI could be related to biochemical damage of the neurons with subsequent lower production of chemical messengers.

Aged↗
PubMed1998

Detection of substance P immunoreactivity in human peripheral leukocytes.

The neuropeptide substance P (SP) has a marked proinflammatory effect and modulates the immune response. In this study, we tested the hypothesis that human peripheral leukocytes contain SP. Resting peripheral leukocytes collected from healthy volunteers (n = 20) were studied by applying a SP rabbit polyclonal antiserum to both flow cytometry and immunohistochemistry. To identify possible changes in Sp expression, we also analyzed both activated T-lymphocytes (cell cultures; n = 5 normal subjects) and neoplastic hematologic samples of different types of leukemias. Flow cytometry showed that normal granulocytes and monocytes contained SP, whereas lymphocytes were generally negative (or weakly positive) with the exception of a few (10-20%) positive subsets. In comparison, activated T-lymphocytes were markedly immunolabeled by SP as well as samples from neoplastic patients demonstrated strong SP immunoreactivity in all cell lineages. This pattern was confirmed by immunohistochemistry on cytospins. Our results support a potential role for SP-mediated immunomodulatory mechanisms both in normal and pathological conditions.

Flow Cytometry↗
PubMed1998

Relevance of gastrointestinal motor disturbances in functional dyspepsia.

Gastrointestinal motor abnormalities are frequent findings in patients with functional dyspepsia. However, these abnormalities are rather non-specific and seem to be restricted to a proportion of patients. Furthermore, they are not necessarily time-linked to symptom perception. The relationship of digestive motor derangements and symptoms in functional dyspepsia remains, therefore, unsettled. A variety of methodological and conceptual shortcomings characterize many of the studies investigating the relationship between gastrointestinal motility disorders and dyspeptic symptoms, and this obviously contributes to a higher level of uncertainty in the field. Recent reports suggest that gastrointestinal dysmotility is associated with perception of some dyspeptic symptoms, at least in a subset of patients. Well-conducted studies using appropriate methodology are needed to verify whether gastrointestinal motor disorders play a causal role in functional dyspepsia and whether this is of clinical relevance.

Dyspepsia↗
PubMed1998

Evidence that tachykinins are the main NANC excitatory neurotransmitters in the guinea-pig common bile duct.

Application of electrical field stimulation (EFS; trains of 10 Hz, 0.25 ms pulse width, supramaximal voltage for 60 s) to the guinea-pig isolated common bile duct pretreated with atropine (1 microM), produced a slowly-developing contraction ('on' response) followed by a quick phasic 'off' contraction ('off peak' response) and a tonic response ('off late' response), averaging 16+/-2, 73+/-3 and 20+/-4% of the maximal contraction to KCl (80 mM), n=20 each, respectively. Tetrodotoxin (1 microM; 15 min before) abolished the overall response to EFS (n 8). Neither in vitro capsaicin pretreatment (10 microM for 15 min), nor guanethidine (3 microM, 60 min before) affected the excitatory response to EFS (n 5 each), showing that neither primary sensory neurons, nor sympathetic nerves were involved. Nomega-nitro-L-arginine (L-NOARG, 100 microM, 60 min before) or naloxone (10 microM, 30 min before) significantly enhanced the 'on' response (294+/-56 and 205+/-25% increase, respectively; n=6-8, P<0.01) to EFS. The combined administration of L-NOARG and naloxone produced additive enhancing effects (655+/-90% increase of the 'on' component, n = 6, P<0.05). The tachykinin NK2 receptor-selective antagonist MEN 11420 (1 microM) almost abolished both the 'on' and 'off late' responses (P<0.01: n=5 each) to EFS, and reduced the 'off-peak' contraction by 55+/-8% (n=5, P<0.01). The subsequent administration of the tachykinin NK1 receptor-selective antagonist GR 82334 (1 microM) and of the tachykinin NK3 receptor-selective antagonist SR 142801 (30 nM), in the presence of MEN 11420 (1 microM), did not produce any further inhibition of the response to EFS (P>0.05; n=5 each). At 3 microM, GR 82334 significantly reduced (by 68+/-9%, P<0.05, n=6) the 'on' response to EFS. The contractile 'off peak' response to EFS observed in the presence of both MEN 11420 and GR 82334 (3 microM each) was abolished (P<0.01; n=6) by the administration of the P2 purinoceptor antagonist pyridoxalphosphate-6-azophenyl-2',4'-disulphonic acid (PPADS, 30 microM). PPADS (30 microM) selectively blocked (75+/-9 and 50+/-7% inhibition, n = 4 each) the contractile responses produced by 100 and 300 microM ATP. Tachykinin-containing nerve fibres were detected by using immunohistochemical techniques in all parts of the bile duct, being distributed to the muscle layer and lamina propria of mucosa. In the terminal part of the duct (ampulla) some labelled ganglion cells were observed. In conclusion, this study shows that in the guinea-pig terminal biliary tract tachykinins, released from intrinsic neuronal elements, are the main NANC excitatory neurotransmitters, which act by stimulating tachykinin NK2 (and possibly NK1) receptors. ATP is also involved as excitatory neurotransmitter. Nitric oxide and opioids act as inhibitory mediators/modulators in this preparation.

Animals↗
PubMed1998

Constipation: a common problem in patients with neurological abnormalities.

Constipation is a frequent complaint among patients with different neurological diseases. This review provides a brief account of the numerous conditions affecting the central, peripheral and intrinsic (enteric) nervous systems in which constipation can be the only clinical manifestation or a component of a complex syndrome. Recent neuropathophysiological acquisitions show that any structural or functional impairment of the intrinsic innervation of the gut, including both developmental (i.e., Hirschsprung's disease and intestinal neuronal dysplasia) and acquired (i.e., either degenerative or inflammatory neuropathies) disorders, can be associated with constipation. Constipation may also arise from derangements of the peripheral nervous system, including diabetes and primary chronic autonomic failure (pandysautonomias). Finally, in the central nervous system, a wide array of disorders (post-traumatic, degenerative, ischaemic or neoplastic) are recognized to determine bowel dysfunction, ultimately leading to constipation. Further understanding of the fine pathophysiological mechanisms through which the intrinsic and extrinsic nerve supplies to the digestive system are involved in idiopathic constipation or in diseases generating this symptom will hopefully lead to a better treatment of this frequent pathological condition.

Central Nervous System Diseases↗
PubMed1997

High prevalence of Helicobacter pylori in liver cirrhosis: relationship with clinical and endoscopic features and the risk of peptic ulcer.

In 153 consecutive patients with cirrhosis we assessed: (1) the prevalence of IgG to Helicobacter pylori and compared it with that found in 1010 blood donors resident in the same area; and (2) the relationships of IgG to Helicobacter pylori with clinical and endoscopic features and with the risk of peptic ulcer. The IgG to Helicobacter pylori prevalence of cirrhotics was significantly higher than in blood donors (76.5% vs 41.8%; P < 0.0005) and was not associated with sex, cirrhosis etiology, Child class, gammaglobulins and hypertensive gastropathy. In both groups, the prevalence of IgG to Helicobacter pylori was significantly higher in subjects over 40. Among patients with cirrhosis a significantly higher prevalence of Helicobacter pylori was found in patients with previous hospital admission (P = 0.02) and/or upper gastrointestinal endoscopy (P = 0.01) and patients with peptic ulcer (P = 0.0004). Multivariate analysis identified increasing age and male sex as risk factors for a positive Helicobacter pylori serology and no independent risk factors for peptic ulcer. The high prevalence of Helicobacter pylori-positive serology found in the present series is related to age and sex and might also be explained by previous hospital admissions and/or upper gastrointestinal endoscopy. Our results do not confirm the role of Helicobacter pylori as risk factor for peptic ulcer in patients with liver cirrhosis.

Adult↗
PubMed1997

Prospective screening of dyspeptic patients by Helicobacter pylori serology: a safe policy? The Italian Helicobacter pylori Study Group.

BACKGROUND AND STUDY AIMS: Endoscopic screening of all dyspeptic patients is not cost-effective, nor is it feasible in many health-care delivery systems. To select the most appropriate candidates, various preendoscopic screening strategies have been proposed, some of which include Helicobacter pylori serology and patient age. We assessed the value of these two criteria in preendoscopic screening of a large series of dyspeptic patients, and compared the results obtained in a referral hospital (university center with an extensive H. pylori research program) with those in nonreferral hospital (participating centers that did not have such a program). PATIENTS AND METHODS: Blood samples for determination of anti-H. pylori IgG antibody were collected from patients with uninvestigated dyspepsia undergoing endoscopy at one referral hospital and in 93 nonreferral hospitals throughout Italy. For IgG antibody assay, an in-house enzyme-linked immunosorbent assay (ELISA) technique was used in the referral hospital, while a commercial kit was used in the nonreferral hospitals. RESULTS: A total of 1638 patients were evaluated at the referral hospital (845 men and 793 women, mean age 46.1 years, range 18-89), and 3281 at the nonreferral hospitals (1718 men and 1563 women, mean age 48.8, range 18-96), respectively. If endoscopy had not been performed in patients who were seronegative for H. pylori and younger than 45 years, 19% versus 17.5% of the tests would have been avoided in the referral and nonreferral hospitals, respectively, while six of 304 ulcers (2%) and no cancers would have been missed versus 35 of 557 ulcers (6.3%) and two of 557 cancers (0.3%). CONCLUSIONS: A screening strategy based on age and H. pylori serology is a valid means of selecting dyspeptic patients for endoscopy; however, the policy needs further refinement for use in nonreferral hospitals.

Adolescent↗