Giuseppe Boari

Time course of circulatory and humoral effects of rapid total paracentesis in cirrhotic patients with tense, refractory ascites

BACKGROUND/AIMS Tense ascites of cirrhosis can be treated with total paracentesis; however, the short-term effects of this procedure are poorly defined. METHODS The circulatory and humoral changes induced by total paracentesis (250 mL/min) were studied in 12 cirrhotics with tense, refractory ascites. Data were collected before, during, and after paracentesis and 24 hours later (after albumin infusion). Hormonal parameters were recorded again 48 hours and 6 days thereafter. RESULTS Paracentesis (10.7 +/- 4.4 L; 64 +/- 20 minutes) caused marked reduction of intra-abdominal, intrathoracic, right atrial, and pulmonary pressures. Heart rate did not change. Cardiac output and heart volumes increased. Systemic vascular resistances and mean arterial pressure slightly decreased. Baseline plasma renin and aldosterone levels were markedly increased; a reduction was already evident during paracentesis with the lowest values at the end of the procedure. All changes were maintained 24 hours later. Hormones regained baseline levels 6 days later. CONCLUSIONS Rapid total paracentesis is accompanied by marked cardiovascular and humoral changes. Some of these changes can be explained by mechanical factors that are directly or indirectly related to the relief of abdominal pressure. However, other changes (systemic vasodilatation, humoral deactivation) have a non-mechanical nature and may depend on reflexes originating from cardiac volume receptor stimulation. Most changes may beneficially (albeit transiently) influence the cardiovascular system of cirrhotic patients with tense ascites.

Effects of venesections and restricted diet in patients with the insulin-resistance hepatic iron overload syndrome.

Abstract: Goal: We evaluated the effect of venesections and restricted diet on iron and metabolic indices and liver function tests in patients with insulin‐resistance hepatic iron overload (IR‐HIO).

Cardiac, Neuroadrenergic, and Portal Hemodynamic Effects of Prolonged Aldosterone Blockade in Postviral Child A Cirrhosis

OBJECTIVES:The present study was designed to determine the effects of long-term antialdosterone treatment on cardiac structural and functional alterations, portal and systemic hemodynamic as well as adrenergic dysfunction characterizing Child A cirrhotic patients with F1 esophageal varices.METHODS:Twenty-two Child A postviral preascitic cirrhotic patients were randomly allocated to 200 mg/day K-Canrenoate (13 patients, age 59.6 ± 2.2 yr, mean + SEM) or no-drug treatment (9 patients, age 61.8 ± 2.3) for a 6-month-period. Measurements, which included hepatic venous pressure gradient (HVPG), left ventricular wall thickness, left ventricular end-diastolic volume and diastolic function (LVWT, LVEDV, and E/A ratio, echocardiography), and muscle sympathetic nerve activity (MSNA, microneurography, peroneal nerve), were obtained at baseline and following 6 months of drug or no-drug treatment. Ten healthy age-matched subjects served as controls.RESULTS:Cirrhotic patients were characterized by increased HVPG, LVWT, and MSNA values and by a depressed E/A ratio. K-Canrenoate treatment significantly reduced HVPG (from 15.3 ± 1.0 to 13.8 ± 0.8 mmHg, p < 0.05), LVWT (from 21.8 ± 0.5 to 20.7 ± 0.6 mm, p < 0.02), and LVEDV (from 99.2 ± 7 to 86.4 ± 6 ml, p < 0.01), leaving E/A ratio and MSNA almost unaltered. No significant change was observed in the untreated group of cirrhotic patients followed for 6 months without intervention.CONCLUSIONS:These data provide evidence that aldosterone blockade by long-term K-Canrenoate administration improves hepatic hemodynamics by lowering HVPG and ameliorates cardiac structure and function by favoring a reduction in LVWT and LVEDV as well. They also show, however, that this therapeutic intervention neither improves left ventricular diastolic dysfunction nor exerts sympathoinhibitory effects.

COGNITIVE PARAMETERS AND MORNING AND EVENING TYPES: TWO DECADES OF RESEARCH (1990-2009)

An important area of study has examined cognitive aspects of Morningness–Eveningness orientation. Optimal times of efficiency in participants classified as Morning and Evening types are of great importance for understanding their cognitive abilities. The present review covers the last two decades (1990–2009), during which the important review by Tankova, Adan, and Buela-Casal appeared, and focuses particularly on attention, memory, and executive functions.

Early effects of total paracentesis and albumin infusion on muscle sympathetic nerve activity in cirrhotic patients with tense ascites

BACKGROUND/AIMS Cirrhotic patients with ascites are characterized by a marked activation of the sympathetic and the renin-angiotensin-aldosterone system. Total paracentesis is associated with a short-lived suppression of the renin-angiotensin-aldosterone system. Little information exists as to whether this favourable effect is parallelled by sympathoinhibition. METHODS In 16 Child C cirrhotic patients (age: 57.1+/-6.2 years, mean+/-SEM) with tense ascites we assessed the time course of the effects of total paracentesis followed by intravenous albumin (6-8 g/l of ascites) on beat-to-beat mean arterial pressure (Finapres), heart rate, plasma norepinephrine, epinephrine (high performance liquid chromatography) and muscle sympathetic nerve activity (microneurography, peroneal nerve). Measurements were obtained under baseline conditions, during staged removal of ascitic fluid (250 ml/min) and 24 h later. The patient remained supine throughout the study period. RESULTS Total paracentesis (10.6+/-1.3 l) induced a decrease in mean arterial pressure (from 95.0+/-2.6 mmHg to 88.2+/-3.2 mmHg, p<0.01), in heart rate (from 82.5+/-3.3 beats/min to 77.1+/-2.8 beats/min, p<0.01) and a reduction in plasma norepinephrine values (from 782+/-133 pg/ml to 624+/-103 pg/ml, p<0.01), which were substantially maintained 24 h later. In eight patients muscle sympathetic nerve activity did not change during paracentesis (from 65+/-7.1 bursts/min to 65+/-7.4 bursts/min, p=NS), but a marked reduction was observed 24 h later (48.4+/-5.6 bursts/min, p<0.01). CONCLUSIONS These data provide the first evidence that total paracentesis exerts an acute marked sympathoinhibitory effect. Whether this is a long-lasting phenomenon and to what extent plasma expansion with albumin contributes to this effects need to be further addressed.

A Partial Least Squares Algorithm Handling Ordinal Variables

The partial least squares (PLS) is a popular path modeling technique commonly used in social sciences. The traditional PLS algorithm deals with variables measured on interval scales while data are often collected on ordinal scales. A reformulation of the algorithm, named Ordinal PLS (OrdPLS), is introduced, which properly deals with ordinal variables. Some simulation results show that the proposed technique seems to perform better than the traditional PLS algorithm applied to ordinal data as they were metric, in particular when the number of categories of the items in the questionnaire is small (4 or 5) which is typical in the most common practical situations.

Selection of Structural Equation Models with the PLS-VB Programme

Parameter and latent score estimates of structural equation models with latent variables may be obtained by the use of the PLS (Partial Least Squares) algorithm. The program PLS-VB, developed in Visual Basic Application as an Excel add-in for this purpose, is presented. Its use for the selection among competing models is also considered.

Validation of the Italian Version of the Morningness-Eveningness Questionnaire for Adolescents by A. Lancry and Th. Arbault

Background This study aimed to validate the Italian version of the Morningness-Eveningness questionnaire for adolescents by Lancry and Arbault. Material/Methods The Morningness-Eveningness Questionnaire by Lancry and Arbault was translated from French into Italian by using forward-backward translation. Students aged 11–15 years old were enrolled from two schools in Milan (Italia). Validation of the questionnaire was performed in subsequent phases. A pre-test was given to 66 students aged 11–15 years (males 57.4%, females 42.6%) from a convenience sample. Syntactic aspects of the pre-test were improved, and the questionnaire in a revised version was re-administered to 292 students of same age (males 43.8%, females 54.1%) from a convenience sample. Results Factor analysis was performed on pre-test data, using the principal component method accounting for Morningness-Eveningness. Problematic items possibly uncorrelated with the extracted factor were identified, and reliability produced a Cronbach’s Alpha close to 0.7. In the test phase factor analysis was performed using the principal component method. Based on reliability analyses, we excluded a number of items because of their low performance, giving rise to a Cronbach’s Alpha of 0.819. Pearson product-moment external correlations between Morningness-Eveningness disposition and temperament, behavioral, and cognitive aspects were evaluated. Conclusions A factor analysis, Cronbach’s alpha and concurrent validity coefficients with disposition, behavior, and cognition, were performed, suggesting potential reliability and validity. The questionnaire is a useful and relevant tool for measuring Morningness-Eveningness disposition in adolescents, which has seldom been investigated with adequate psychometric instruments.

Scale Reliability Evaluation for a-priori Clustered Data

According to the classical measurement theory, the reliability of a set of indicators related to a latent variable describing a true measure can be assessed through the Cronbach’s \(\alpha\) index. The Cronbach’s α index can be used for τ-equivalent measures and for parallel measures and represents a lower bound for the reliability value in presence of congeneric measures, for which the assessment can properly be made only ex post, once the loading coefficients have been estimated, e.g. by means of a structural equation model with latent variables.Once assumed the existence of an a-priori segmentation based upon a categorical variable Z, we test whether the construct is reliable all over the groups. In this case the measurement model is the same across groups, which means that loadings are equal within each group as well as they do not vary across groups. A formulation of the Cronbach’s α coefficient is considered according to the decomposition of pairwise covariances in a clustered framework, and a test procedure assessing the possible presence of congeneric measures in a multigroup framework is proposed.

A Simplified Latent Variable Structural Equation Model with Observable Variables Assessed on Ordinal Scales

The communication is related to a wide empirical research promoted by the Universita Cattolica del Sacro Cuore of Milan (UCSC) aimed at acquiring an insight into the real work possibilities of its graduates in the last seven years, as well as the appreciation and satisfaction of the firms which offered them a job position. The group of 1,264 firms which have a special connection with UCSC, regarding new job appointments, was considered and they were given a questionnaire, using web for sending and answering. The analysis of the 203 complete answers was conducted by having recourse to a structural equation model with latent variables.