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Biomedical subjects

F Luzza

Publications and source records attributed to F Luzza.

At least 19 recordsLinked to original sources
PubMed2006

Torsades de pointes in congenital long QT syndrome following low-dose orphenadrine.

We report the case of a woman, affected by congenital long QT syndrome (LQTS), who experienced three syncopal episodes shortly after the assumption of a low dose of orphenadrine. The ECG revealed a QT interval of 600 ms, and the corrected QT interval (QTc) was 537 ms. No structural cardiac disease was demonstrated by echocardiography. Orphenadrine treatment was discontinued. During the first 12 h of monitoring, three short-lasting, asymptomatic episodes of torsades de pointes occurred. No other sustained ventricular arrhythmia was revealed at Holter monitoring in the following days. During the ensuing 6 months, the patient remained asymptomatic, and the QTc did not change. Orphenadrine is an analogue of diphenhydramine, an antihistaminic drug that produces sodium channel blockade similar to that caused by quinidine and other Class Ia antiarrhythmic drugs. Our case rises the suspicion that orphenadrine could cause life-threatening arrhythmias in LQTS even at a low dose, and independently from concomitant assumption of potentially QT-prolonging drugs.

Aged↗
PubMed2004

High seroprevalence of Helicobacter pylori infection in non-institutionalised children with mental retardation.

Eighty-four children with mental retardation (34 boys, 50 girls; age range 2-18 years, median 6 years) and 84 age- and gender-matched outpatient controls were studied. All children were living at home, had never stayed in an institution, and came from the same urban area. Seropositivity for Helicobacter pylori was found in 42 (50%) of 84 mentally retarded children and 16 (19%) of 84 controls (p < 0.01). Socio-economic factors did not differ between the two groups. The findings indicated that a higher prevalence of H. pylori infection occurs in children with mental retardation, regardless of whether they are institutionalised.

Adolescent↗
PubMed2003

Tilt-induced pseudosyncope.

Using the head-up tilt test (HUTT) we evaluated 986 consecutive patients affected by unexplained syncope. In 266 patients the test induced bradycardia and/or hypotension resulting in syncope or presyncope, thus allowing a diagnosis of neurally mediated syncope. In three other patients (0.3% of the entire population and 1% of the all positive tests) HUTT provoked loss of consciousness despite no significant change in heart rate and/or blood pressure. In all three cases unconsciousness was prolonged and no pathological finding was present except lack of response. This phenomenon has been defined as 'pseudosyncope' and related to psychiatric illness. Pseudosyncope induced by HUTT reproduced the clinical events, so the test outcome was considered a true positive response. Our experience suggests that HUTT may contribute to the recognition of psychiatric disorder in some patients affected by unexplained syncope.

Adolescent↗
PubMed2003

[Thrombo-embolic risk evaluation in patients with atrial fibrillation. Role of echocardiography].

Atrial fibrillation (AF) is the most common observed cardiac arrhythmia and is the most frequent condition associated with thromboembolic events in patients with or without mitral valve disease. The source of cardiac emboli is the left atrium, the left atrial appendage or, less frequently, the left ventricle. Emboli may also originate from aortic atherosclerotic plaques. It is important to identify patients at risk in order to perform the appropriate therapy. Risk stratification is multiparametric, being based on clinical, laboratory, and echocardiographic data. Several trials have pointed out the role of echocardiography in the evaluation of anatomic and functional parameters associated with thromboembolic risk. Transthoracic echocardiography (TTE) does not provide sufficient information regarding posterior cardiac structures, being its sensitivity in detecting thrombi relatively low (33-72%). Transesophageal echocardiography (TEE) in contrast, has an almost 100% sensitivity; this technique is, therefore, mandatory in patients with AF for an adequate prevention of thromboembolism. The echocardiographic information joined with clinical features allow to stratify, in a proper way, the risk of every single patient.

Atrial Fibrillation↗
PubMed2002

[Pathophysiology of congestive heart failure].

Pathophysiology of congestive heart failure (CHF) has undergone a remarkable evolution during the last two decades. CHF is now regarded especially as a neurohormonal disease and not only as a cardiocirculatory impairment. Many studies have emphasized that an abnormal neuroendocrine activation precedes the development of clinically recognized heart failure and plays an important pathogenetic role in progression of this disease. In patients with CHF, moreover, circulating levels of some neurohormonal factors have an independent negative prognostic value. More recently immunological and molecular biology studies have also demonstrated the negative effects exerted by some cytokines and by apoptosis. Correction of neurohormonal disorder is the rationale of therapeutical approach to patients with CHF and appears the only way to significantly decrease mortality. In this review the role of neuroendocrine activation in the pathophysiology of CHF is analyzed.

Angiotensin II↗
PubMed2002

[Detection of left ventricular endocardial border with tissue harmonic imaging].

BACKGROUND: Ultrasonic wave propagation in human tissues is not linear. As a consequence, harmonic waves, whose frequency is a multiple (harmonic) of the emitted frequency, are generated. Tissue Harmonic Imaging (THI) processes only the second harmonic frequency in order to improve the signal-to-noise ratio of the received signal. The study was aimed at investigating the impact of THI on the detection of the Left Ventricular (LV) endocardial border. Attention was paid to determine which LV walls were analysed more clearly with THI rather than with conventional Fundamental Frequency Imaging (FFI). METHODS: We compared the FFI and the THI visualization of the 16 LV segments and of the 6 LV walls in 30 consecutive patients by scoring the images as bad, sufficient or good. The equipment used was a GE Vingmed System Five (Orten, Norway). RESULTS: Images were good in 85% of segments explored with THI, whereas FFI provided good images in 47% of segments (p<0.001). From the apical window, visualization of the apex, lateral wall and anterior wall significantly improved with THI; using the parasternal approach, imaging of posterior wall was definitely better with THI than with FFI. CONCLUSIONS: THI enhances both endocardial visualization and global image quality. Tech-nical development, however, increases the diagnostic possibilities of echocardiography but does not substitute the operator's experience.

Echocardiography↗
PubMed2001

Lansoprazole-based triple therapy versus ranitidine bismuth citrate-based dual therapy in the eradication of Helicobacter pylori in patients with duodenal ulcer: a multicenter, randomized, double-dummy study.

BACKGROUND: The optimal treatment regimen for eradication of Helicobacter pylori in patients with duodenal ulcer has yet to be determined. Based on a search of MEDLINE, no studies have been performed comparing a proton pump inhibitor-based triple therapy regimen with a ranitidine bismuth citrate (RBC)-based dual therapy regimen, both containing clarithromycin. OBJECTIVE: This study was undertaken to compare the efficacy of lansoprazole (LAN)-based triple therapy with that of RBC-based dual therapy in H pylori-infected patients with duodenal ulcer. METHODS: Patients were randomized to receive either 1 week of triple therapy with LAN 30 mg BID, clarithromycin 500 mg BID, and tinidazole 500 mg BID, followed by 3 weeks of LAN 30 mg BID, or 2 weeks of dual therapy with RBC 400 mg BID plus clarithromycin 500 mg BID, followed by 2 weeks of RBC 400 mg BID. Eradication of H pylori was defined as negative results on both the urease quick test and histologic examination > or =4 weeks after the end of treatment. Duodenal healing and recurrence rates were assessed endoscopically at 8 weeks and 6 months. A per-protocol (PP) analysis was conducted for each efficacy end point. Also conducted were an intent-to-treat (ITT) analysis in which patients with missing data were considered failures, and an observed analysis (OBS), which included patients with an evaluable result after treatment, regardless of compliance. RESULTS: One hundred eighty-five patients (126 men, 59 women; age range, 18-76 years; mean age, 43 years) were enrolled and randomized to treatment. In the LAN and RBC groups, respectively, H. pylori eradication rates were 92.6%, 93.1%, and 72.8% versus 78.6%, 77.9%, and 64.5% in the PP (P = 0.02), OBS (P = 0.01), and ITT analyses. The corresponding duodenal ulcer healing rates were 98.6%, 98.7%, and 83.7% versus 90.8%, 91.5%, and 81.7%; these differences were not statistically significant. Side effects were mild, occurring in 20.7% of LAN patients and 17.2% of RBC patients. Ulcer recurred in 2 RBC patients. No difference was observed between treatments in terms of the occurrence of gastritis or improvement of symptoms. CONCLUSION: Based on the results of the PP and OBS analyses, LAN-based triple therapy was superior to RBC-based dual therapy for the eradication of H. pylori in patients with duodenal ulcer.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2001

QRS complex voltage changes associated with supraventricular tachycardia.

INTRODUCTION: The aim of this study was to evaluate the changes in ventricular complex voltage associated with narrow QRS supraventricular tachycardia (SVT). METHODS AND RESULTS: One hundred forty-five patients undergoing catheter ablation for SVT, 85 with AV nodal reentrant tachycardia (AVNRT) and 60 with AV reentrant tachycardia (AVRT) due to a concealed accessory pathway, were studied. Four consecutive tachycardia beats and four consecutive sinus beats were analyzed, excluding the last tachycardia complex and the first sinus one. For each of the 12 leads, the QRS complex voltage was measured, and the results of four beats were averaged both in SVT and in sinus rhythm (SR). The sum (sigma) of the QRS voltages measured in the 12 leads during SVT (sigmaSVT) and SR (sigmaSR) were calculated, as well as the QRS axis during SVT and SR. QRS complex voltage was significantly increased during SVT, with respect to SR, in leads II, III, aVR, aVF, and V2 to V6. In addition, sigmaSVT was significantly greater than sigmaSR. Only lead V1 showed a significant voltage decrease during SVT. These voltage changes were almost identical in patients with AVNRT and patients with AVRT. No relationship was found between tachycardia rate and QRS voltage variation. The QRS axis showed a significant shift during SVT, from 55.8 degrees to 64.5 degrees. CONCLUSION: QRS voltage increase occurs in reentrant SVT, independent of the underlying reentrant circuit. The phenomenon likely depends on tachycardia-related reduced ventricular filling. This could result in displacement of the heart in such a way that the left ventricle becomes closer to the precordial electrodes (proximity effect). Alternatively, decreased intracavitary blood mass could diminish the intracardiac short-circuiting of potentials, resulting in augmented transmission of cardiac vectors to the body surface.

Adolescent↗
PubMed2001

Advanced A-V block with apparent A-V junctional escape complexes because of dual A-V nodal pathways.

We report a patient with second degree A-V block in whom several sinus impulses were conducted over the slow A-V nodal pathway, resulting in P-R intervals so prolonged to suggest a diagnosis of intermittent advanced A-V block with A-V junctional escape complexes. However, the "escape" cycles were markedly irregular, and moreover, "escape" complexes often occurred with R-R cycles shorter than those ended by conducted sinus beats. These observations suggested that no escape mechanism was present. The marked variability of P-R intervals was a manifestation of dual A-V nodal pathways: short P-R intervals expressed conduction over the fast pathway, whereas long P-R intervals corresponded to sinus impulses conducted over the slow pathway.

Aged↗
PubMed2001

Antral nodularity identifies children infected with Helicobacter pylori with higher grades of gastric inflammation.

BACKGROUND: The endoscopic pattern of antral nodularity is a peculiar finding in children with Helicobacter pylori infection. The aim of this study was to determine whether this finding is related to more severe gastritis. METHODS: One hundred seventy-four consecutive children (median age 8.7 years) referred for gastroscopy were studied. Biopsy specimens from the antrum and body of the stomach were taken to assess H pylori status, gastritis score, and lymphoid follicles. Clinical diagnosis, major symptoms and endoscopic findings were recorded. RESULTS: Eighty-four (48%) children (median age 10.5 years) had evidence of H pylori infection. The endoscopic pattern of antral nodularity was found only in children infected with H pylori (34/84, 40.5% vs. 0/90, 0%, p < 0.0001% 100% specificity, 40.5% sensitivity). Among all children infected with H pylori, the gastritis score was higher (p < 0.0001) in those with antral nodularity (n = 34) than in those without (n = 50). Completely normal gastric mucosal histology was never found in children infected with H pylori with antral nodularity. The presence and number of lymphoid follicles was strongly related to the finding of antral nodularity (p < 0.01). CONCLUSIONS: The endoscopic pattern of antral nodularity identifies children with H pylori infection, severe gastritis, and increased lymphoid follicles.

Biopsy↗
PubMed2001

[The second tissue harmonic signal: from physics principles to clinical application].

The second harmonic signals received from organs are due to the non linear properties of tissue which cause distortion of the transmitted signal and are not primarily caused by the transmission of a harmonic frequency. The velocity of ultrasound propagation depends on the density of the insonified material. During the compression phase, the tissue becomes denser, and the ultrasound waves travel faster through the tissue than during the rarefaction phase; the compression phase tends to overtake the rarefaction phase. The ultrasound waveform thus, undergoes a distortion that becomes greater as the distance from the transducer increases. Due to these effects, the tissue tends to generate harmonics and hence shifts energy from the fundamental to the harmonic bands. There are several reasons why harmonic tissue imaging increases the signal-to-noise ratio and facilitates interpretation. In technically difficult patients, there is often a diffuse haze due to distortion of the transmitted beam by shallow surface layers or to reverberations between the skin and ribs. These distortions and reverberations consist almost entirely of ultrasound energy at the fundamental frequency. When the returned signal is filtered at the harmonic so as to reject the fundamental frequency, the clutter and haze are removed and the image becomes more clear and defined. A further reason for the decrease in artifacts and clutter is the side-lobe level reduction in the second harmonic beam. Thus, harmonic beams are narrower and have lower side-lobe levels than fundamental ones. There are several clinical applications of harmonic tissue imaging. These include the correct definition of endocardial borders resulting in an improved assessment of left ventricular function at rest as well as during stress testing, the delineation of the left atrial appendage, the detection of atrial right to left shunting, and left atrial spontaneous echo contrast. Moreover, improved endocardial visualization leads to better endocardial tracking with acoustic quantification and to more segments being interpretable with the anatomic M-mode.

Acoustics↗
PubMed2000

Up-regulation of the IL-12 receptor beta 2 chain in Crohn's disease.

Crohn' s disease (CD) is a chronic intestinal inflammatory disorder characterized by aberrant mucosal Th1 cell activation and production of IL-12, the major Th1-driving factor. The T cell response to IL-12 is dependent on the expression of a specific receptor composed of two subunits, termed IL-12Rbeta1 and IL-12Rbeta2. The content of IL-12Rbeta2, as measured at the mRNA level, is crucial in regulating Th1 differentiation. In this study we therefore investigated IL-12Rbeta2 RNA transcripts in CD. IL-12Rbeta2 expression was increased in active CD as well as Helicobacter pylori (HP)-associated gastritis and Salmonella colitis compared with that in inactive CD, ulcerative colitis, noninflammatory controls, and celiac disease. In contrast, IL-12Rbeta1 transcripts were expressed at comparable levels in all samples. In CD, IL-12Rbeta2 expression strictly correlated with tyrosine phosphorylation of STAT4, a key component of the IL-12-dependent Th1 polarization. This was associated with a pronounced expression of IFN-gamma. Transcripts for IL-12/p40 were detected in CD, HP-positive, and Salmonella colitis patients, but not in celiac disease, indicating that IL-12Rbeta2 up-regulation occurs only in IL-12-associated Th1 gastrointestinal diseases. Finally, we showed that stimulation of lamina propria mononuclear cells with IL-12 enhanced IL-12Rbeta2, suggesting that IL-12 regulates IL-12Rbeta2 expression in human gastrointestinal mucosa. The data show that the signaling pathway used by IL-12 to induce Th1 differentiation is increased at the site of disease in CD, further supporting the view that IL-12/IL-12R signals contribute to the inflammatory response in this condition.

Colitis↗
PubMed2000

Up-regulation of IL-17 is associated with bioactive IL-8 expression in Helicobacter pylori-infected human gastric mucosa.

Helicobacter pylori (HP)-associated gastritis is characterized by an increased number of acute and chronic inflammatory cells secreting cytokines that contribute to maintain and expand the local inflammation. Locally induced IL-8 is believed to play a major role in the HP-associated acute inflammatory response. Factors/mechanisms that regulate IL-8 induction are, however, not fully understood. In the present study we investigated whether HP infection is associated with an increased production of IL-17, a T cell-derived cytokine capable of modulating IL-8 gene expression. We showed that both IL-17 RNA transcripts and protein were expressed at a higher level in the whole gastric mucosal and lamina propria mononuclear cell samples from HP-infected patients than in those from uninfected subjects. HP: eradication was associated with a marked down-regulation of IL-17 expression. The addition of a neutralizing anti-IL-17 Ab to the gastric lamina propria mononuclear cell cultures resulted in a significant inhibition of IL-8 secretion, indicating that IL-17 contributes to enhance IL-8 in the HP-colonized gastric mucosa. Consistently, stimulation of MKN 28 cells, a gastric epithelial cell line, with IL-17 increased IL-8 secretion. Finally, conditioned medium from the IL-17-stimulated MKN 28 cell cultures promoted the in vitro polymorphonuclear leukocyte migration. This effect was inhibitable by a neutralizing IL-8 but not IL-17 Ab. Together, these data indicate that biologically active IL-17 production is increased during HP: infection, suggesting the possibility that this cytokine may play an important role in the inflammatory response to the HP colonization.

Adjuvants, Immunologic↗
PubMed2000

Altered IgG(4) renal clearance in patients with inflammatory bowel diseases. Evidence for a subclinical impairment of protein charge renal selectivity.

BACKGROUND: A loss of intestinal glycosaminoglycans (GAGs) has been shown in inflammatory bowel diseases (IBD). Since GAGs are involved in the regulation of renal protein filtration and GAGs disruption is associated with anionic proteinuria, we examined whether changes in the selectivity of renal protein filtration occur in IBD. METHODS: From 46 patients with IBD (17 with Crohn's disease (CD), and 29 with ulcerative colitis (UC)) and 21 healthy subjects, urine and serum samples were obtained. Albumin, total IgG and IgG(4) clearances were measured using sensitive methods. Serum p-ANCA and TNF-alpha were tested. RESULTS: Median IgG(4) clearance was 0.041 ml/ min/10(-3) in patients with UC and 0.10 ml/ min/10(-3) in CD patients, both significantly higher than in controls (0.03 ml/min/10(-3)) (P<0.03). IgG(4) clearance was above the upper normal limit in 9/17 CD (53%) and in 10/29 UC (34.5%). Eighteen of 19 patients showing abnormal IgG(4) clearance were taking mesalazine. In patients on maintenance oral mesalazine, IgG(4) clearance was higher than that in patients off treatment (0.12 vs 0.03 ml/min/10(-3), P=0.04). No clinical/laboratory sign of renal dysfunction was documented in patients with altered IgG(4) clearance and maintained on mesalazine treatment. CONCLUSION: Renal protein charge permselectivity is impaired in 40% of patients with IBD with no overt proteinuria. Our data suggest that altered IgG(4) clearance may represent a subclinical marker of renal involvement in IBD.

Administration, Oral↗