Electroanalytical determination and fractionation of copper in wine.

Eight different bottled wines (six red wines and two white ones) were studied for copper determination and fractionation. For this purpose, copper determination by square wave voltammetry (SWV) and potentiometry (PSA) stripping analysis using Hg electrodes (drop and film, respectively) were carried out. Two direct procedures for the determination of total copper in wine are proposed; in both cases, drastic treatment of samples is not necessary, the procedures are very fast (estimated time to carry out an analysis is <10 min) and require no deaeration. Fractionating treatment consists of various HCl additions followed by the addition of ethylenediamine. Precision (RSD < 3%) and accuracy (recovery > 98%) data justify that both methods proposed are valid for total copper determination in wine. The wines studied displayed similar behaviors regarding fractionation: the percentages of total copper fractionated in each step are statistically similar: differences are lower than 2 S.

Determination of Cr (in small quantities) by adsorptive stripping voltammetry: a comparative study of square wave versus differential pulse.

The usefulness of an analytical method must be measured according to its practical application possibilities. A comparative study has been carried out here between the SW (working in an open atmosphere) and DP (working with de-aerated solutions) variants of catalytic-stripping adsorptive voltammetry applied to the determination of chromium traces in triethylenetetraminehexaacetic acid (TTHA) medium. In order to optimise the analytical signal, accumulation potential, nitrate ion concentration, pH, and TTHA concentration parameters were evaluated. Four linearity ranges were established within the interval 0.5-2000 nmol L(-1) chromium concentration in the cell, each with the recommended accumulation time. Quality parameters such as repeatability, linear regression, validity limits, precision, and sensitivity were evaluated. The SW variant is significantly advantageous when the chromium concentration in cell is less than 10 nmol L(-1) and even more if analysis time, cost, and being able to work in an open atmosphere are considered. The results are comparable to those obtained using GTAAS. Employing a CRM (tomato leaves), the accuracy is 1-4%. The proposed procedure, using tree leaves as samples, has been successfully tested for the possible monitoring of chromium contamination of the atmosphere.

Heart rate variability in childhood obesity.

UNLABELLED: Obesity is characterized by hemodynamic and metabolic alterations. Autonomic control on cardiac function involvement is controversial. The aim of the study was to assess early sign of cardiac autonomic dysfunction in obesity, using time- and frequency-domain heart rate variability (HRV) analysis in a pediatric population. METHODS: 32 obese children (OB) (17 M, 15 F; 13.9 +/- 1.7 y) were compared with 13 healthy lean subjects (7 M, 6 F; 12.9 +/- 1.6 y). For each participant, the authors performed a clinical examination, laboratory testing, blood pressure (BP) measurements, and 24-hour electrocardiograph/ambulatory BP monitoring. The spectral power was quantified in total power, low-frequency (LF) power, index of sympathetic tone, high-frequency (HF) power, index of vagal tone, and LF/HF ratio. Low frequency and HF were averaged to obtain 3 measures: 24-hour, daytime, and nighttime levels. Total, long-term, and short-term time-domain HRV values were calculated. RESULTS: The obese children had higher casual and ambulatory BP, and higher fasting glucose, insulin, and triglyceride levels. Overall HRV values were not significantly lower in OB. The obese children had significantly lower 24-hour and nighttime high-frequency normalized units, and time-domain measures of vagal activity. Low-frequency power showed an inverse but not significant pattern. The OB group had significantly greater 24-hour and nighttime LF/HF ratios. CONCLUSIONS: The authors found an increase in heart rate and in BP associated with parasympathetic heart rate control decrease in stabilized obese normotensive children.

Ambulatory blood pressure monitoring and clinical characteristics of the true and white-coat resistant hypertension.

The resistant hypertension has been differentiated in true resistant hypertension and white-coat resistant hypertension by using ambulatory blood pressure monitoring. White-coat resistant hypertension was defined as high clinic blood pressure, despite triple treatment for at least 3 months, but day-time blood pressure values < 135/85 mmHg. The aim of this study was to evaluate the presence of different clinical characteristics between two types of resistant hypertension. The study group consisted of 49 patients with essential hypertension, resistant to an adequate and appropriate triple-drug therapy, that included a diuretic, with all 3 drugs prescribed in near maximal doses and that had persistently elevated clinic blood pressure (> 140/90 mm Hg), for at least 3 months. They represented the 2% of 2500 hypertensive outpatients that referred at our Hypertension Unit. Patients with white-coat resistant hypertension (n=19) were older (p<0.05) than those with true resistant hypertension (n=30). The sodium intake (p<0.05) and alcohol intake (p<0.05) were significantly higher in patients with true resistant hypertension than in those with white-coat resistant hypertension. The renin plasma activity and plasma aldosterone were higher (p<0.05) in patients with true resistant hypertension than in those with white-coat resistant hypertension with normal plasma electrolyte balance. There were no significant differences in mean values of office systolic and diastolic blood pressures between white coat resistant hypertensives and true resistant hypertensives (165+17 vs 172+28 and 98+12 vs 102+14 mmHg). Day-time and night-time ambulatory 24-h-systolic and diastolic blood pressures were significantly higher in the true resistant hypertensive patients when compared with white-coat resistant hypertensives (153+15 vs 124+10 mmHg and 97+9 vs 76+6 mmHg all p<0.001). Day-time and night-time ambulatory 24-h-heart rate were significantly higher in the true resistant hypertensive patients when compared with white-coat resistant hypertensives (79+11 vs 71+9 beats/min; p<0.01; 68+9 vs 60+6 beats/min, p<0.001). The ABP readings were analysed by a Fourier series with 4 harmonics. According to the runs test both two groups of patients showed a circadian rhythm for both systolic and diastolic blood pressure. The nocturnal fall in SBP, DBP and HR was not different in both groups of patients. In conclusion, our findings showed that true resistant hypertensive patients were characterized both by higher heart rate and higher plasma renin activity values as an expression of a possible increased sympathetic activity. Thus, the combination of ABPM with the assessment of the clinical characteristics allow to differentiate better the true drug-resistant hypertension from the white coat resistant hypertension.

Absence of D147E mutation of CYP11B2 gene in hypertensive patients with increased corticosterone and aldosterone production.

OBJECTIVE: 11beta-Hydroxylase and aldosterone synthase are two highly homologous genes involved in different forms of human hypertension and in different animal models of hypertension. It has been shown that the conservative substitution D147E in the human CYP11B2 gene results in an increased production of corticosterone and aldosterone in vitro. A gene conversion between the CYP11B1 and CYP11B2 genes could be responsible for such a substitution. METHODS: In this study we investigated the presence of the mutation D147E of CYP11B2 in a group of 128 patients with primary aldosteronism, 68 patients with essential hypertension and increased corticosterone production and in 48 normal volunteers. RESULTS AND CONCLUSIONS: We did not identify any patient carrying this mutation, indicating that if it exists it is very rare and so has no relevance in determining the increased steroid excretion seen in some subtypes of human hypertension.

Evaluation of the influence of physical activity on the plasma concentrations of several trace metals.

Our study was carried out with the aim of evaluating the influence that the degree of physical activity may have on plasma concentrations of essential and toxic elements. Copper and zinc, elements of known importance in basic cellular processes, have been analysed as essential, and cadmium and lead as toxic for the body in abnormal doses. The study was performed on a total population of 50 healthy individuals, 34 of them professional sportsmen and the rest who undertook moderate physical activity (control group), all of them living in a polluted environment (Madrid, Spain). Sampling was conducted at the beginning of the season (October). Electro-analytical techniques of proved reliability and accuracy were used for the determination of the metals. The results were related to data obtained using graphite furnace atomic absorption spectrophotometry and by use of biological reference materials. We found significantly higher zinc plasma concentrations in the sportsmen involved in anaerobic-type training (judo, fencing) compared to those undertaking aerobic activities (endurance, cycling) (P < 0.05). The values in both cases were higher than those found in the control group. Our study showed an increase of plasma copper concentrations in professional sportsmen, especially in those performing anaerobic activities, compared to those subjects undertaking moderate activity (control group) (P < 0.05). In summary, our results showed that there were no deficiencies of copper and zinc in the athletes studied at the beginning of the season. The levels were higher than those of the control population. As for the toxic metals, cadmium and lead, we observed lower levels in the athletes than in the control group (cadmium P < 0.005, lead P < 0.05). These results may indicate the existence of possible elimination systems for these metals in athletes, when they are training in a polluted environment.

Prevalence of risk factors in acute ischemic cerebrovascular disease (CVD) in elderly patients from eastern Sicily.

Hundred and forty elderly patients (76 males and 64 females, over 65 years of age) were consecutively admitted to the Institute between November 1989 and April 1993, in order to (i) verify if the risk factors, reported in other Italian areas and regions of the world, are prevalent also in our region, and (ii) outline a secondary prevention strategy against the statistically most important risk factors. There were 111 cases of ischemic stroke (58 males and 53 females) and 29 cases of reversible ischemic attack (RIA) (18 males and 11 females). The percental occurrence of the following risk factors were determined: total cholesterol > 240 mg/dl, HDL cholesterol < 35 mg/dl, triglycerides > 180 mg/dl, fibrinogen > 450 mg/dl, hematocrit > 45%, hypertension, diabetes mellitus, cigarette smoking, familial ischemic events, previous ischemic CVD, ischemic cardiac disease, embolic cardiopathy. In males with ischemic stroke the most frequent risk factors were: hypertension (43%), fibrinogen > 450 mg/dl (37.9%), diabetes mellitus, cigarette smoking and previous ischemic CVD (25.8%). In females with ischemic stroke a clear prevalence of hypertension (69.8%), ischemic cardiopathy and previous ischemic CVD (47%) and diabetes mellitus (41.5%) were observed. In males with RIA hypertension (50%) and cigarette smoking (38%). Females with RIA presented a high prevalence of reduced HDL cholesterol, lower than 35 mg/dl (77.7%), hypertension (63.6%) and ischemic cardiopathy (54.5%). The results indicate that there are no highly significant differences between the data reported by other authors on the most important acute ischemic CVD risk factors in Italy and elsewhere. Arterial hypertension and diabetes mellitus are the most important risk factors of cerebral ischemic events in both sexes. The diffusion of cigarette smoking among women in the last thirty years must be taken into consideration. Although it does not represent a risk factor for elderly women today, it may do in the future. Therefore, antismoking campaigns must be more decisive and targeted at both sexes.

Hepatitis C virus genotypes in elderly patients with chronic hepatitis C.

The importance of determination of hepatitis C virus (HCV) genotypes and subtypes has been demonstrated not only as epidemiological characteristics, but also as prognostic factors regarding the seriousness of the disease and response to interferon (IFN) in patients with chronic hepatitis C (CHC). Aim of this study was to determine HCV genotypes in a group of elderly patients with CHC, in order to acquire epidemiological data on the prevalence of HCV genotypes in Eastern Sicily, and to evaluate any relationship with the seriousness of the disease and with the response to IFN. The study was carried out on 22 patients with CHC, aged from 65 to 75 years. The prevalence of HCV-RNA subtypes in elderly patients (Group A) was compared with two other groups: Group B aged from 36 to 64 years; and Group C aged from 20 to 35 years. HCV-RNA proved to be positive in 20 of the 22 patients in Group A, and in 100% of these cases the prevalent subtype was 1b; in the other two groups the occurrence of other subtypes was more frequent, especially in the younger ages. In conclusion, the subtype 1b is indigenous in our region and it cannot be proposed as the only prognostic factor for seriousness of the disease and response to IFN, especially in elderly patients.

Chronic hepatitis C in elderly patients: clinical, histological and virological features.

Some clinical, histological and virological features, efficacy and safety of interferon (IFN) therapy were evaluated in elderly patients with chronic hepatitis C (CHC). We enrolled 22 patients aged 65-75 (mean age: 68.3 +/- 3.17 years); 15 males and 7 females. In all cases the hepatitis C virus RNA (HCV-RNA) was determined before, during and after the therapy, and HCV sub-types were established; 15 patients underwent hepatobiopsy. At entry, the duration of disease was: 6 patients 1-3 years, 2 patients 4-10 years, 14 patients 11-30 years; alanine-aminotransferase (ALT) = (3.17 +/- 1.15) x N (N = normal value); aspartate-transaminase (AST) = 2.28 +/- 1.6 x N; gamma-glutamyl-transpeptidase (gGT) = 1.4 +/- 1.1 x N; platelets = 164,000 +/- 66,000/mm(3); histological pattern: 2 mild chronic active hepatitis (CAH), 5 CAH, 2 severe CAM, 6 CAH with liver cirrhosis (LC); histological activity index (HAI) (14 patients) = 11.14 +/- 4.5 (range 5-17); scores according to Scheuer: lobular 2.28 +/- 1.13, portal 2.71 +/- 0.99, fibrosis 2.35 +/-1.33; HCV-RNA +ve: 20 patients, HCV-RNA -ve: 2 patients; HCV-subtypes: 1b 20/20 (100%), 1b+1a 1/20 (5%), 1b+ 2a 1/20 (5%). Treatment was applied to 18 patients, for 3-12 months; 5 received alpha-IFN2a; 5 received alpha-IFN2b, 3 lymphoblastoid IFN, all at a dose of 3 mU thrice per week; 3 patients received 6 mU beta-IFN thrice per week. Therapy over 6 months was applied to 16 patients: Complete response (CR) was observed in 8 patients (50%), one of them was with long-term CR (over 12 months after therapy); 5 have had relapse and 2 patients are still under treatment. Partial response (PR) was observed in 4 patients (25%), no response (NR) in 4 patients (25%). Side effects were moderate and self-limited. Loss of HCV-RNA was shown in some patients with PR and in all patients with CR, but only temporarily.