The Von Willebrand Factor Antigen Plasma Concentration: a Monitoring Marker in the Treatment of Aortic and Mitral Valve Diseases.

Von Willebrand disease is a commonly inherited bleeding disorder caused by defects of von Willebrand factor (vWF). In the most common valve diseases, aortic valve stenosis (AVS) and mitral valve regurgitation (MVR), a bleeding tendency has been described in a number of patients. This has been associated to a high turbulence of blood flow through the compromised valve, promoting degradation of vWF with loss of high-molecular-weight multimers of vWF (HMWM), leading to an acquired von Willebrand syndrome (AvWS). We analysed three groups of patients, one affected by AVS, treated with transcatheter aortic valve implantation (TAVI), the second group of patients affected by MVR, treated with Mitraclip® mitral valve repair. The third group was represented by patients also affected by AVS, but not eligible for TAVI and treated with standard surgery. A fourth group of patients that underwent percutaneous coronary intervention (PCI) with stenting was used as a control. Our results demonstrated that the level of vWF measured as antigen concentration (vWF:Ag) increases in all cohorts of patients after treatment, while in control PCI patients, no modification of vWF:Ag has been registered. Western blot analysis showed only a quantitative loss of vWF in the pre-treatment time, but without significant HMWM modification. The monitoring of the vWF:Ag concentration, but not the quality of HMWM, can indicate the status of blood flow in the treated patients, thus introducing the possibility of using the vWF antigen detection in monitoring the status of replaced or repaired valves.

Role of the TAp63 Isoform in Recurrent Nasal Polyps.

The pathogenic molecular mechanisms underlying the insurgence of nasal polyps has not been completely defined. In some patients, these lesions can have a recurrence after surgery removal, and the difference between recurrent and not recurrent patients is still unclear. To molecularly characterize and distinguish between these two classes, a cohort of patients affected by nasal polyposis was analysed. In all patients we analysed the p63 isoform expression using fresh tissues taken after surgery. Moreover, confocal immunofluorescence analysis of fixed sections was performed. The results show high ΔNp63 expression in samples from the nasal polyps of patients compared to the normal epithelia. Analysis of the expression level of the TAp63 isoform shows differential expression between the patients with recurrence compared to those not recurring. The data, considered as the ΔN/TAp63 ratio, really discriminate the two groups. In fact, even though ΔNp63 is expressed in non-recurrent patients, the resulting ratio ΔN/TAp63 is significantly lower in these patients. This clearly indicates that the status of TAp63 expression, represented by the ΔN/TAp63 ratio, could be considered a prognostic marker of low recurrence probability. In these samples we also investigated the expression of OTX2 transcription factor, known to be a selective activator of TAp63, detecting a significant correlation. Database analysis of HNSCC patients showed increased survival for the patients presenting OTX2 amplification and/or overexpression. These results, together with the fact that TAp63 can be selectively upregulated by HDAC inhibitors, open the possibility to consider local treatment of recurrent nasal polyps with these molecules.

Interfacing Sca-1(pos) mesenchymal stem cells with biocompatible scaffolds with different chemical composition and geometry.

An immortalized murine mesenchymal stem cell line (mTERT-MSC) enriched for Lin(neg)/Sca-1(pos) fraction has been obtained through the transfection of MSC with murine TERT and single-cell isolation. Such cell line maintained the typical MSC self-renewal capacity and continuously expressed MSC phenotype. Moreover, mTERT-MSC retained the functional features of freshly isolated MSC in culture without evidence of senescence or spontaneous differentiation events. Thus, mTERT-MSC have been cultured onto PLA films, 30 and 100 microm PLA microbeads, and onto unpressed and pressed HYAFF-11 scaffolds. While the cells adhered preserving their morphology on PLA films, clusters of mTERT-MSC were detected on PLA beads and unpressed fibrous scaffolds. Finally, mTERT-MSC were not able to colonize the inner layers of pressed HYAFF-11. Nevertheless, such cell line displayed the ability to preserve Sca-1 expression and to retain multilineage potential when appropriately stimulated on all the scaffolds tested.

Atrial natriuretic factor (ANF) and ANF receptor C gene expression and localization in the respiratory system: effects induced by hypoxia and hemodynamic overload.

Atrial natriuretic factor (ANF) and ANF receptor C (ANF.RC) expression have been investigated in healthy and cardiomyopathic hamsters (CMPH) with widespread necrosis of the diaphragm and myocardium leading to respiratory and heart failure. ANF- and ANF.RC-producing cells were localized in different structures of the respiratory system, and the regulation of their expression by the individual and/or combined action of hypoxia and hemodynamic overload was analyzed. The study was performed in 20-, 90-, and 150-day-old animals using immunohistochemistry, in situ hybridization, Northern blot, and RIA analyses. ANF was shown to be expressed in the tracheo-bronchial epithelium and muscle and, to a lesser extent, in the alveolar wall and muscular media of the pulmonary arteries and extraparenchymal pulmonary veins in both healthy hamsters and CMPH. In 150-day-old CMPH, hypoxia (PaO2 < 50 mm Hg) induced a 10-fold increase in ANF messenger RNA accumulation and a 6-fold increase in the immunoreactive ANF (IR-ANF) concentration in lungs, as quantitated by RIA. As plasma IR-ANF concentrations were elevated in all CMPH age groups, it was most likely produced by the myocardium. ANF.RC messenger RNA was homogeneously distributed throughout the entire respiratory system and was increased 2-fold in hypoxic 150-day-old CMPH only. These results suggest that ANF originating in the respiratory system exerts only paracrine effects on different structures of the respiratory system in addition to the action of circulating ANF. Hemodynamic overload (left ventricular end-diastolic pressure, 17.20 +/- 3.80 mm Hg) might contribute to enhanced ANF gene expression only in extraparenchymal pulmonary vein walls of 150-day-old CMPH. We also propose that ANF.RC overexpression might be a protective mechanism operated via either ANF clearance or inhibition of adenylate cyclase activity to counteract exaggerated smooth muscle relaxation.

Altered lipid metabolism in the failing heart of cardiomyopathic hamsters (UM-X7.1).

The lipid composition of different anatomic regions of 150 day-old UM-X7.1 cardiomyopathic hamster and age-matched controls (Syrian golden hamsters) was examined. Cardiomyopathic hamsters exhibit a phospholipid to protein ratio higher than healthy animals in atria, whereas the contrary is true in the other anatomic regions examined. In all tissues the cholesterol to phospholipid ratio is higher in cardiomyopathic hamster than in controls. Healthy and UM-X7.1 hamsters differ substantially as far as the percent distribution of fatty acids in total lipids is concerned, the lipids from cardiomyopathic animals accumulating fatty acids of the omega-6 series and being relatively poor in monoenoic fatty acids. The different fatty acid composition of heart lipids appears to be a consequence of a generalized disturbance of the lipid metabolism in cardiomyopathic hamsters during congestive heart failure.

Selective changes in DNA binding activity of transcription factors in UM-X7.1 cardiomyopathic hamsters.

UM-X7.1 hamsters (CH) are considered a representative model for human cardiomyopathy. CH display the loss of the cytoskeletal delta-sarcoglycan protein, associated with myocardium remodeling and fatal reduction of heart functional efficiency. Even though altered redox balance and calcium homeostasis have already been reported to affect cardiomyocyte function, the molecular mechanisms underlying this pathology are largely unknown. We found no significant differences in DNA binding activity of redox-related (NF-kappaB, Sp1, AP-1 and AP-2) transcription factors in heart ventricles of 90 day-old CH, compared to normal animals. On the other hand, DNA binding activity of calcium-dependent transcription factors NF-AT3 and CREB were increased and decreased respectively in CH vs. normal ventricles. Western blot experiments confirmed the down regulation of CREB levels and suggest a novel regulation mechanism for this transcription factor in the heart. Our results are consistent with recent studies on NF-AT3, GATA4 and CREB transgenic mice, and provide clues for the comprehension of pathogenetic mechanisms of hamster hereditary cardiomyopathy.

Effects of alpha-human atrial natriuretic peptide in guinea-pig isolated heart.

The aim of the present investigation has been to ascertain whether or not atrial natriuretic peptides (ANP) can exert a direct effect on myocardial contractility. Alpha-human ANP (alpha-hANP) concentrations ranging from 1 pM to 50 nM have been used to perfuse guinea-pig isolated hearts in a non-recirculating Langendorff apparatus. A dual concentration-related effect has been induced by alpha-hANP on myocardial function. A maximal increase of +LV dP/dtmax (+56%; P < 0.001) has been observed when guinea-pig hearts were perfused with 100 pM alpha-hANP, whereas a 25% decrease (P < 0.01) occurred with 50 nM alpha-hANP. Similar effects have also been induced by alpha-hANP on the coronary flow rate (CFR). A significant CFR increase (maximal at 10 pM alpha-hANP) was induced by picomolar concentrations of alpha-hANP, whereas a progressive decrease, which was maximal (-28%; P < 0.01) at 50 nM alpha-hANP, was observed with nanomolar concentrations of the peptide. No effects have been observed on heart rate. These results suggest that ANP has direct effects on both vascular and myocardial muscle cells. Coronary vasoconstriction induced by nanomolar concentrations of ANP can contribute to the cardiodepression, whereas ANP in picomolar concentrations can induce a coronary vasodilation which is not coupled with the enhanced myocardial contractility. The latter is the likely expression of a direct effect of the peptide on myocardial function.

The influence of severe bulb deformity on duodenal ulcer relapse.

In order to evaluate the prognostic role of duodenal bulb deformation in the recurrence of peptic ulcer, duodenal bulb morphology and the complete healing of duodenal ulcer were endoscopically evaluated in sixty patients, who were subsequently allocated at random to either maintenance therapy with ranitidine or no treatment. Endoscopic checkups were done at regular intervals, up to the first ulcer recurrence. As expected, long-term ranitidine treatment significantly reduced the relapse rate (12 month cumulative relapse rate was 32% versus 86% in the untreated). A set of prognostic factors which might interfere with this result (sex, age, alcohol consumption, history of ulcerous relatives, duration of the disease, previous H2-blocking treatment, previous complications, smoking and morphology of the duodenal bulb) were evaluated by multivariate analysis using the Cox regression model. Only duodenal bulb morphology appeared to have any independent prognostic value. In the untreated group ulcer recurrence seemed to occur earlier (median relapse time = 2 months) in the patients with severe non-stenosing bulb deformity, and later in those with normal or mildly deformed bulb (median relapse time = 8 months); ranitidine treatment delayed relapse in deformed bulb patients (median relapse time = 14 months) and almost eliminated it in those with normal duodenal bulb morphology. No association was found between the presence of duodenal bulb deformity and the above-mentioned covariates. Our study confirms the primary importance of anti-H2 treatment and suggests that anatomical characteristics of the duodenal bulb also influence the occurrence of ulcer relapse.

[Atrial natriuretic factor and pulmonary function]. / Fattore natriuretico atriale e funzione polmonare.

The aim of this review is to provide a critical and concise discussion of present knowledge on the role of atrial natriuretic factor (ANF) in physiological as well as pathological pulmonary conditions. The lung contributes only to a small extent to the production of circulating ANF; on the other hand, the lung represents the major degrading site of the protein. Plasmatic ANF concentration increment during lung disease may therefore be due to a reduction in ANF plasma removal enzyme rather than to increased ANF production. Lung tissue shows more ANF receptor sites than any other organ. The effect of ANF on bronchial and pulmonary artery muscle lining is particularly evident. In fact ANF administration in asthmatic patients leads to bronchodilation comparable to dilation induced by salbutamol. Furthermore, elevated levels of circulating ANF seem to influence fluid redistribution through alveolar-capillary membrane leading to protein mobilization through the alveolar space. On the contrary, in the cardiomyopathic hamster ANF induces relevant guanylate cyclase activation before the animal has developed hemodynamic changes. Guanylate-cyclase activation may protect the lung through counteracting pulmonary edema formation, as shown by fluid reduction in alveolar spaces following pneumotoxic agents administration. This effect seems independent of natriuretic and hypotensive ANF effects.

[Esaprazole vs sulglicotide in the treatment of dyspeptic patients with chronic superficial gastritis of the antrum]. / Esaprazolo vs sulglicotide nel trattamento di pazienti dispeptici portatori di gastrite cronica superficiale dell'antro.

Fifty dyspeptic patients with histologically proven chronic superficial antral gastritis were treated for 6 weeks, in a randomized single-blind study, with esaprazole (450 mg bid) or sulglicotide (200 mg tid). Both drugs significantly improved the symptomatic score after 3 and 6 weeks (p less than 0.01), and the percentual rate of improvement was similar in the two groups studied. Similarly, both treatments significantly reduced the inflammation of gastric mucosa. Drugs were ineffective in clearing Helicobacter pylori from the antral mucosa (as assessed by the urease test, performed at entry and after 6 weeks). No side effects occurred after esaprazole or sulglicotide administration. The results of the present study suggest that esaprazole, a new gastroprotective drug, may have a role in the therapy of dyspeptic patients with chronic superficial gastritis.

[The physiopathological aspects and new therapeutic approaches in cardiac-circulatory failure]. / Aspetti fisiopatologici e nuovi indirizzi terapeutici nell'insufficienza cardio-circolatoria.

Pathophysiological mechanisms are reviewed concerning the onset and the perpetuation of the clinical features of congestive heart failure. This syndrome is a severe condition of poor prognosis and bad life quality which in the last decades has reached, in the western industrial countries, the highest levels of general mortality, mainly due to the high prevalence of hypertensive and ischaemic myocardiopathies in the last years. To the clinical features of heart failure mainly contributes a deregulation of the physiological compensatory mechanisms contemporarily and concurrently activated following the primary deficiency of the heart pump function. In physiological conditions, following the myogenic adapting mechanisms reflex mechanisms intervene, activated by intracardiac and aortic and carotid-sinus mechanoreceptors following the variations in intracardiac and intravascular pressure and generally evoking negative feed-back effects. In patients with heart failure arterial high pressure mechanoreceptors respond to the reduction in effective arterial pressure thus provoking a deactivation of the tonic inhibition on the sympathetic cardiovascular drive. This leads to an activation of peripheral and renal vasoconstrictor tone, to a raised medullary catecholamine incretion, to heart rate and inotropism stimulation, and to an increase in pituitary gland ADH production as well as to an activation of renin-angiotensin-aldosterone system (RAAS). Analogous vasoconstrictive, and sodium and water retentive effects can be elicited by endothelin produced by endothelial cells and found in high plasma levels in CHF. These excitatory effects, leading to a rise in systemic vascular resistance and to hydro-electrolytic retention with volume expansion, are not efficiently counteracted by the opposite effects triggered by cardiopulmonary vagally mediated mechanoreceptors activated by the raised cardiac filling pressure and leading to sympathetic nervous inhibition, peripheral and renal vasodilation, ADH and RAAS inhibition. Analogous effects should be provoked by the raised production, due to enhanced heart wall distension, of atrial natriuretic factor leading to vasodilation, natriuresis and diuresis. Reduced sensitivity of cardiopulmonary baroreceptors and lowered production of ANF due to structural cardiac changes could represent, according to most opinions, the main factors responsible for the prevailing sympathetic activation and hydro-saline retention in CHF. The activation of cardiopulmonary sympathetic positive-feed back afferents, could be also involved in the characteristic alteration of the vago-sympathetic balance in heart failure. The persistent reduction in heart pump function could lead to the instauration of vicious circles among the various regulatory systems and create an overcompensation condition.(ABSTRACT TRUNCATED AT 400 WORDS)

Proliferating cells in adult cardiomyopathic hamster ventricles.

Myocardium of hereditary hypertrophic cardiomyopathic hamsters UM.X7.1 between 60 and 90 days of life shows large clusters of densely packed, actively proliferating cells with a rhabdoid appearance. Immunohistochemical studies showed that most of proliferating cells express, although with variable patterns, muscular markers such as desmin, alpha-sarcomeric actin, myoglobin and alpha/gamma-smooth muscle actin. The simultaneous occurrence of a poorly differentiated appearance, intense proliferating activity and expression of muscular markers seems to indicate that cluster cells may be muscular in origin and that their proliferation can be a fundamental pathophysiological step in the onset of cardiomyopathy. The possibility that myocardial proliferating cells originated from de-differentiated adult cardiomyocytes, which undergo a short cellular proliferation program, or from not fully matured (fetal) cardiomyocytes scattered throughout the myocardium is discussed.

Phospholipid base exchange enzyme activity in sarcolemmal membranes from the heart of cardiomyopathic hamsters.

The activity of phospholipid base exchange enzymes has been evaluated in cardiac sarcolemmal membranes from Syrian Golden hamsters and from a hamster strain (UM-X7.1) characterized by a genetic form of hypertrophic cardiomyopathy. No choline base exchange activity and only a little serine base exchange activity were detected, whereas the ethanolamine base exchange enzyme was found highly active in membranes from both strains. For this reason, the present study is focussed on the ethanolamine base exchange enzyme. The apparent Km for ethanolamine of ethanolamine base exchange enzyme from Syrian Golden membranes and from UM-X7.1 strain membranes are 18 and 32 microM, respectively. The specific activity of the sarcolemmal ethanolamine base exchange enzyme is lower in the UM-X7.1 strain than in Syrian Golden hamsters. The calcium-dependence of the enzyme appears different when the membranes from the two strains are compared. Indeed, after removal of the membrane-bound divalent cations, comparable activities are found in both membrane preparations, whereas, upon addition of Ca2+ to the incubation mixtures, the activity of the enzyme is enhanced in the membranes from Syrian Golden strain more than in those from UM-X7.1 strain. The cholesterol content of sarcolemmal membranes is higher in the cardiomyopathic strain than in the Syrian Golden hamsters. A possible relation between changes of the membrane lipid composition and of the ethanolamine base exchange activity is discussed.

Kinetic changes of ethanolamine base exchange activity and increase of viscosity in sarcolemmal membranes of hamster heart during development of cardiomyopathy.

The activity of the phospholipid base exchange enzyme specific for ethanolamine has been measured in cardiac sarcolemmal membrane preparations from Syrian golden and UM-X7.1 cardiomyopathic hamsters. In Syrian golden hamsters, the Km of the enzyme for ethanolamine does not change with age, whereas it almost doubles in membranes from cardiomyopathic animals, from the 30th to the 150th day of age. During the same period, the membrane cholesterol content increases by 68% in cardiomyopathic hamsters, whereas it does not change significantly in the Syrian golden hamster strain. As a consequence, in the adult animal, the cholesterol to phospholipid ratio and the viscosity of sarcolemmal membranes are higher in UM-X7.1 strain than in Syrian golden hamsters. A cause-consequence relationship between the enzymatic changes and the compositional modifications in the sarcolemma occurring in UM-X7.1 hamsters during the development of cardiomyopathy is proposed.

The cardiomyopathic hamster as model of early myocardial aging.

Few experimental studies are available on aging, because of the lack of suitable experimental models to test specific pathophysiologic mechanisms. In the present study, the cardiomyopathic Syrian hamster is proposed as experimental model of the aging myocardium. In fact, the hamster myocardium develops an early alpha to beta myosin isoform shifting in ventricles that is independent of hemodynamic overload and repeats the phenomenon physiologically occurring in healthy hamsters during the entire lifespan. At the same time, in atria there is a progressive decline of ANF production that is independent of intracavitary pressure. Conversely, ANF production in ventricles is enhanced before the onset of hemodynamic overload, but parallel to the increase in the fibrotic proportion of the ventricular wall. These characteristics mimic the modifications occurring in otherwise healthy aged mammals and candidate the cardiomyopathic hamster as a model of early myocardial aging.

Clinical efficacy and safety of cisapride and clebopride in the management of chronic functional dyspepsia: a double-blind, randomized study.

The clinical efficacy and the safety of chronic oral administration of cisapride, a new gastrointestinal prokinetic agent, (10 mg tid) and clebopride (0.5 mg tid) was assayed in 48 outpatients affected with functional dyspepsia, in a randomized double-blind study. Each of the drugs induced a significant reduction in dyspeptic symptoms after 2 and 4 weeks (p less than 0.001). Two patients, given clebopride, dropped out of the study because of severe side effects during the first week of treatment. Mild adverse reactions were reported in 6 out of 23 cisapride-treated patients and in 10 out of 20 clebopride-treated patients who completed the study. The most common side effect of cisapride was diarrhoea and that of clebopride was drowsiness. Cisapride appears to be as effective as clebopride in reducing dyspeptic symptoms and seems to induce less severe side effects.

Insulin deficiency and reduced expression of lipogenic enzymes in cardiomyopathic hamster.

Evidence is given that the heart of the cardiomyopathic UM-X7.1 hamster has a lipid composition different from that of the same tissue isolated from animals of the Syrian hamster parent strain. Also, noncardiac tissues from cardiomyopathic and healthy hamsters exhibit significant compositional differences. On the basis of these preliminary observations, a comparative study of the hepatic biosynthesis of lipids in cardiomyopathic and healthy Syrian hamsters was undertaken. The results obtained indicate that the cardiomyopathic hamster is characterized by a generalized disturbance of lipid metabolism. In particular, the fatty acid synthase and stearoyl-CoA desaturase activities were significantly lower in the liver of UM-X7.1 hamsters than in age-matched healthy controls fed the same diet. Northern blot analysis of the mRNAs encoding the two enzymatic proteins and the "lipogenic" S14 nuclear protein indicated that the transcription of the respective genes was impaired in UM-X7.1.Short-term dietary manipulations modulated the expression of the above-mentioned genes both in cardiomyopathic and healthy animals. However, dietary carbohydrates were less effective in inducing the expression of lipogenic enzymes in UM-X7.1 liver than healthy controls. The main determinant of the metabolic defect pointed out in the present work appears to be represented by the low insulin level detectable in the plasma of the cardiomyopathic hamster.-Vecchini, A., L. Binaglia, M. Bibeau, M. Minieri, F. Carotenuto, and P. Di Nardo. Insulin deficiency and reduced expression of lipogenic enzymes in cardiomyopathic hamster. J. Lipid Res. 2001. 42: 96;-105.