[Research on Pisa University student's life style and health]. / Indagine sugli stili di vita e la salute degli studenti universitari dell'ateneo pisano.

Surveys on life and health conditions of university students besides providing useful epidemiologic data partly related to the young population. They are potentially useful for the intervention planning aimed to remove possible environmental or behavioural risk factors. Following these purpose a survey sample about 1200 student attending the University of Pisa was carried out through an anonymous questionnaire about 41 questions focused on behaviours and lifestyles of young people, possible health problems, self-perception of the health state, the use of public health services, and the more commonly used (or preferred) sources of information on health topics. The results suggest that although the self perception of the state of health is broadly positive for the majority of students, there is also a significant frequency of individuals declaring significant at risk behaviours (persistence of sexual practices at risk, drug use, alcohol and smoke abuse). The consumption, also sporadic, of psicoattive substances has been declared gives beyond 40% of the students, in particular 37% asserts to have tried drugs. The habit to smoke appeared diffused much between the students; the percentage of smokers turns out equal to 41% in total (40% females, 42% males). 76% of the interviewed ones has declared to be sexually active, the percentage of those who have declared multiple relations or occasional is elevated (12%), and 47% of the students asserts to use the condom with fixed partner and 77% with occasional partner. Moreover there seems to be a significant association between the changes in the diet and other lifestyles that are due to the "university lifestyle" (as a consequence of leaving the family or increased commuting) and the insurgence of several types of sickness, e.g. gastroenteric disturbances and fever attacks. Finally, the present investigation suggests that few interventions on services offered to students (such as accommodation, teaching structures and especially the creation of a "health office" where students can acquire information on health and other topics related to their condition) could have a significantly beneficial impact on the general state of health of the university population.

C-type natriuretic peptide does not affect plasma and urinary adrenomedullin in man.

To investigate whether C-type natriuretic peptide (CNP) at pathophysiological plasma levels stimulates the release of adrenomedullin (ADM) in man, six healthy subjects (three men and three women, mean age 35 +/- 3 years, range 33-40 years) received an intravenous infusion of synthetic human CNP-22 (2 pmol kg-1 min for 2 h), in a single-blind, placebo-controlled, random order, cross-over study, with measurements of the plasma levels of cyclic guanosine monophosphate (cGMP), ADM, renin and atrial natriuretic peptide (ANP), arterial pressure, heart rate, renal blood flow (para-aminohippurate clearance), glomerular filtration rate (creatinine clearance), and the urinary excretion rates of cGMP, ADM and sodium. Infusion of CNP induced increases in its own levels (from 1.17 +/- 0.11 up to 21.13 +/- 1.41 pmol l-1) without modifying the plasma levels of cGMP, ADM, renin and ANP, the urinary excretion rate of ADM and cGMP, renal haemodynamics and sodium excretion. These data indicate that circulating CNP is not involved in the regulation of ADM release, renal haemodynamics and sodium excretion in man.

Different effects of atrial and C-type natriuretic peptide on the urinary excretion of endothelin-1 in man.

1. Following the observation that brain natriuretic peptide enhances the urinary excretion rate of endothelin-1, the relationship between natriuretic peptides and urinary endothelin-1 was further investigated. Six healthy volunteers received, on three different occasions, increasing doses of atrial or C-type natriuretic peptide (0, 2 and 4 pmol.min-1.kg-1 for 1 h each), or placebo.2. Atrial natriuretic peptide caused significant increases in the urinary excretion of cGMP, sodium and endothelin-1, without affecting plasma endothelin-1, renal plasma flow, glomerular filtration rate and urine flow rate. C-type natriuretic peptide did not modify any of these parameters. During atrial natriuretic peptide infusion, urinary endothelin-1 directly correlated with plasma atrial natriuretic peptide, urinary cGMP and sodium excretion.3. These results indicate that enhancement of the urinary excretion of endothelin-1 by natriuretic peptides is dose-dependent and somewhat related to their ability to bind to natriuretic peptide receptors A, activate guanylate cyclase and induce a natriuretic response.

Proposals and solutions for autonomy of the disabled and elderly.

The aim of this paper is to present DEFIE (Disabled and Elderly people Flexible Integrated Environment) a project of the CEC to develop a multimedia integrated system that allows the elderly and motor and/or sensory impaired to command and control domestic and working environments with a high degree of self-sufficiency and safety. The goal of this study has been to implement a precompetitive prototype of a modular system capable of satisfying the needs of a heterogeneous group of disabled and elderly users.

[Zinc blood levels in 73 puerperal women. Correlation with obstetric and neonatal complications]. / Livelli ematici di zinco in 73 puerpere. Correlazione con complicanze ostetriche e neonatali.

BACKGROUND: Low plasma zinc concentrations in pregnant women have been associated with certain obstetric and foetal complications. However, there is no agreement in previous studies and mediterranean populations have not been extensively studied. METHODS: The plasmatic zinc was tested in 73 mothers, within 24 hours post-partum, in order to evaluate an association between plasmatic zinc and various obstetric and fetal complications. The women were all from the Florence province and were admitted for delivery at the II Maternity Ward of the University of Florence (Third level Center); mothers of twins and foreign mothers were excluded. Subjects were consecutively included in the study. The values pointed out in a control group (n = 28) were compared with the hematic zinc of a) women who delivered by cesarean section (CS) for acute fetal distress or by operative delivery with vacuum extractor (n = 9), b,c) mothers whose children weighted over the 90th (LGA: n = 11) or under the 10th percentile (SGA: n = 13), and d) mothers who delivered prematurely (n = 12). The subjects included in two or more groups, were not considered. RESULTS: The plasmatic zinc of the control group has been significantly higher than that of mothers who delivered by vacuum extractor or by urgent CS (p < 0.0001) and than that of mothers whose newborns were LGA (p < 0.0024). The hematic zinc of the control group is not higher than that of mothers with SGA or premature children. CONCLUSIONS: The conclusions is drawn that even a relative zinc deficiency may negatively potentiate certain obstetric abnormalities in fetal development or in delivering.

Acute effects of physiological increments of brain natriuretic peptide in humans.

To investigate the effects of physiological increases in plasma brain natriuretic peptide concentration in humans, we studied six healthy volunteers who received incremental infusions (0.25 pmol/kg per minute in the first hour and 0.50 pmol/kg per minute in the second) of synthetic human brain natriuretic peptide-32 in a placebo-controlled, crossover study. Peptide plasma levels were 1.69 +/- 0.39 pmol/L at baseline and rose 1.5- and 3-fold with the lower and higher doses, respectively. These values were within the normal range and also comparable to those reported in patients with mild essential hypertension. The urinary excretion rate of cGMP also increased during brain natriuretic peptide infusion, indicating stimulation of natriuretic peptide receptors. Peptide administration induced a significant 1.7-fold increase in urinary sodium excretion without affecting renal plasma flow (para-aminohippurate clearance), glomerular filtration rate (creatinine clearance), and urine flow rate. Fractional proximal sodium reabsorption (lithium clearance method) was unchanged, and fractional distal sodium reabsorption significantly decreased. Brain natriuretic peptide caused no changes in arterial pressure, heart rate, hematocrit, and serum proteins, but it exerted an inhibitory effect on the renin-aldosterone axis, as indicated by the significant 50% or more decrease of plasma renin activity and urinary excretion rate of aldosterone. These results suggest that brain natriuretic peptide may be involved in the overall regulation of body fluid and cardiovascular homeostasis in humans, mainly through its natriuretic and endocrine effects.

Acylphosphatase: a potential modulator of heart sarcolemma Na+,K+ pump.

Acylphosphatase, purified from cardiac muscle, catalyzes the hydrolysis of the phosphorylated intermediate of heart sarcolemmal Na+,K(+)-ATPase. This effect was remarkable even using acylphosphatase amounts (100-300 units/mg of membrane protein) near the lower limit of the physiological range; besides the low value of the apparent Km, on the order of 10(-7) M, indicates that the enzyme has a high affinity for this special substrate. The results of a dot-immunobinding assay suggest the possibility of an interaction between acylphosphatase and native, undenaturated Na+,K(+)-ATPase. Moreover, when added to sarcolemmal vesicles, acylphosphatase was found to affect the functional properties of the Na+,K+ pump with regard to the rate of both ATP hydrolysis and cation transport. However, while ATPase activity and Na+ uptake were stimulated, the last at a greater extent, the active K+ transport was inhibited, so that the Na+/K+ ratio, which was calculated as 1.50 without acylphosphatase, rose to 6.68 in the presence of 300 units/mg of vesicle protein of this enzyme. Taken together, the reported results indicate that acylphosphatase, because of its hydrolytic activity on the phosphoenzyme intermediate, induces a sort of "uncoupling" effect on the heart sarcolemmal membrane Na+,K+ pump. Possible mechanisms for such an effect, which suggests a potential role of acylphosphatase in the control of this active transport system, are discussed.

Cardiovascular and renal effects of low dose brain natriuretic peptide infusion in man.

We evaluated the effects of pathophysiological levels of human brain natriuretic peptide (BNP), a recently identified cardiac hormone with natriuretic activity, by determining the hemodynamic and renal responses to low dose infusion (4 pmol/kg.min for 1 h, from 1500-1600 h) of human synthetic BNP in five healthy volunteers in a randomized placebo-controlled crossover study. Compared to placebo, BNP induced significant increases in effective renal plasma flow (para-aminohippurate clearance), glomerular filtration rate (creatinine clearance), urine flow rate, and sodium excretion without affecting blood pressure, heart rate, cardiac output (echocardiographic method), peripheral vascular resistance, PRA, plasma aldosterone, or plasma norepinephrine to any significant extent. Exploration of segmental sodium handling by the lithium clearance technique showed that the natriuretic effect of BNP was due to both an increase in filtered sodium load and a reduced distal sodium reabsorption. These results indicate that the high plasma BNP levels observed in disease states, such as heart failure, may contribute to the regulation of renal hemodynamics and sodium excretion.

[Behavior of ionized calcium in hypertensive and normotensive patients]. / Comportamento del calcio ionizzato in soggetti ipertesi e normotesi.

Serum concentrations of ionized calcium have been measured in a group of 38 patients with essential hypertension (26 women and 12 men with mean age 61 +/- 12 years) and in a group of 19 normotensives (14 women and 5 men with mean age 70 +/- 12 years). Serum Ca++ levels were significantly lower in hypertensives than in normotensives (4.16 +/- 0.43 mg/dl and 4.46 +/- 0.38 mg/dl respectively, with p less than 0.05). The lower serum concentrations found in hypertensives may be due ions in arterial smooth muscle cells may cause an increase of vascular tone and peripheral resistances. Our results support, in agreement with other Authors, the possible role of ionized calcium in the pathogenesis of essential hypertension.

The protective effects of taurine on hypoxia (performed in the absence of glucose) and on reoxygenation (in the presence of glucose) in guinea-pig heart.

In isolated guinea-pig heart submitted to hypoxia in the absence of substrate and subsequent reoxygenation 1-20 mM taurine decreases LDH release and ventricular arrhythmias, and the recovery of normal electrical and mechanical activity is increased. The taurine effect is dose-dependent, and is not mimicked by beta-alanine. Moreover, taurine reduces the increase in calcium gain of reoxygenated heart.

[Interlaboratory quality control for the determination of blood lead. Initial experiences in Tuscany]. / Controllo di qualità interlaboratoriale per la determinazione del piombo ematico. Prime esperienze in Toscana.

Results of an interlaboratory precision comparison programme of blood lead determination are presented. The samples consisted of bovine haemolyzed whole blood to which were added in pool small quantities of lead nitrate aqueous solutions to obtain two different concentrations of the metal (i.e. about 30 and 70 micrograms/dl). After each pool was well mixed it was divided into 15 ml portions in screw-top linear polyethylene vials and stored at -25 degrees C. The analytical methods used by the five public health laboratories participating in the programme were based on atomic absorption spectrophotometry. Three laboratories used methods which incorporate discrete sampling techniques (i.e. tantalum boat, electrothermal atomisation) and the remaining two, a method incorporating a sample preconcentration by solvent extraction and flame atomisation. During the six months period of the programme, fifty five results were obtained for each of the two pools of blood. Common statistical methods and the graphic system devised by Youden were used for data analysis. An acceptable agreement among results from the five laboratories has been obtained. The usefulness of this type of programme in improving analytical proficiency has been confirmed.

Magnesium in tumoral tissues, in the muscle and serum of subjects suffering from neoplasia.

Mg2+ content is significantly increased in malignant neoplastic mammary tissue compared with normal mammary tissue and benign neoplastic tissue of the breast. Significant variations of the ion were not found in the skeletal muscle tissue (rectus abdominis and pectoral muscle) of subjects suffering from malignant neoplasia with diffused metastasis. It seems that the variation of Mg2+ content in malignant neoplastic mammary tissue is a local factor linked with the biological anomalies of the neoplastic cell.

[Hypouricemia and xanthinuria. Observation of 3 cases]. / Ipouricemia e xantinuria. Osservazione di tre casi.

The Authors refer about three cases of asymptomatic xanthinuria pointed out after the discovery of very low serum uric acid levels (below 1 mg/100 ml). The above-mentioned cases come out from 137.194 evaluation of serum uric acid carried out in a period of about four years. The values of serum and urinary uric acid and those of total oxypurines in urine of same kinsmen of the three patients have been evaluated; all these values were in the normal range.