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C Leclercq

Publications and source records attributed to C Leclercq.

At least 55 records · Page 3Linked to original sources
PubMed2000

Estimates of the theoretical maximum daily intake of erythorbic acid, gallates, butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) in Italy: a stepwise approach.

The three recent EU directives which fixed maximum permitted levels (MPL) for food additives for all member states also include the general obligation to establish national systems for monitoring the intake of these substances in order to evaluate their use safety. In this work, we considered additives with primary antioxidant technological function for which an acceptable daily intake (ADI) was established by the Scientific Committee for Food (SCF): gallates, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT) and erythorbic acid. The potential intake of these additives in Italy was estimated by means of a hierarchical approach using, step by step, more refined methods. The likelihood of the current ADI to be exceeded was very low for erythorbic acid, BHA and gallates. On the other hand, the theoretical maximum daily intake (TMDI) of BHT was above the current ADI. The three food categories found to be main potential sources of BHT were "pastry, cake and biscuits", "chewing gums" and "vegetables oils and margarine"; they overall contributed 74% of the TMDI. Actual use of BHT in these food categories is discussed, together with other aspects such as losses of this substance in the technological process and percentage of ingestion in the case of chewing gums.

Adolescent↗
PubMed2000

The influence of survey duration on estimates of food intakes and its relevance for public health nutrition and food safety issues.

OBJECTIVE: To examine the influence of food consumption survey duration on estimates of percentage consumers, mean total population intakes and intakes among consumers only and to consider its relevance for public health nutrition and food safety issues. DESIGN: Prospective food consumption survey. SETTING: A multicentre study in five centres in the European Union-Dublin, Ghent, Helsinki, Potsdam and Rome. SUBJECTS: Teenage subjects were recruited through schools; 948 (80%) out of 1180 subjects completed the survey. INTERVENTIONS: 14-day food diaries were used to collect the food consumption data. RESULTS: For mean total population intakes, 53% of the foods had slopes significantly different to 0 (P<0.05). In practical terms (g/day), these differences were small, with 41% of foods having differences of </=1 g/day and a further 35% having differences of 1-5 g/day. Estimates of percentage consumers based on 3 days and 14 days were 1.9 and 3.6 times the 1-day estimate, respectively. For 72% of foods, at least 50% of non-consumers on day 1 became consumers over the subsequent 13 days. Estimates of mean consumer only intakes based on 3 days and 14 days were 53% and 32% of the 1 day value. CONCLUSION: In practical terms, survey duration influences estimates of percentage consumers and intakes among consumers only but not mean total population intakes. Awareness of this influence is important for improved interpretation of dietary data for epidemiological studies, development of food-based dietary guidelines and food chemical intakes. SPONSORSHIP: The Institute of European Food Studies, a non-profit research organization based in Trinity College Dublin. European Journal of Clinical Nutrition (2000) 54, 166-173

Adolescent↗
PubMed2000

A pilot experience with permanent biventricular pacing to treat advanced heart failure.

BACKGROUND: The prognosis and quality of life of patients with advanced heart failure remain poor. The purpose of this study was to evaluate new nonpharmacologic approaches. Biventricular pacing was proposed in this indication, based on the encouraging results of acute hemodynamics studies. METHODS: Fifty patients with drug-resistant heart failure (New York Heart Association [NYHA] class III/IV, 16 of 34) were consecutively implanted with biventricular pacemakers. All patients had severe dilated cardiomyopathy and intraventricular conduction delay. Survival, NYHA class, electrocardiogram, echocardiographic data, and exercise tolerance were assessed over a mean follow-up period of 15.4 +/- 10. 2 months. RESULTS: At the end of follow-up, 55% of patients were alive without heart transplantation or left ventricular assistance device. The mortality rate was significantly lower in class III (12. 5%) than in class IV patients (52.5%). In survivors, biventricular pacing significantly improved symptoms (NYHA class 2.2 +/- 0.5 at follow-up vs 3.7 +/- 0.5 at baseline) and exercise tolerance ((. )VO(2) peak 15.5 +/- 3.4 mL/min per kilogram at follow-up vs 11.1 +/- 3 mL/min per kilogram at baseline). CONCLUSIONS: Biventricular pacing appears to improve the functional status of patients with dilated cardiomyopathy with advanced heart failure. The technique appears to be attractive as an additive treatment, especially in class III patients. Controlled randomized studies are needed to validate this novel concept.

Aged↗
PubMed2000

Dietary intake exposure to sulphites in Italy--analytical determination of sulphite-containing foods and their combination into standard meals for adults and children.

The theoretical risk of exceeding the Acceptable Daily Intake (ADI) for sulphites has mostly been examined on the basis of a worst-case scenario. In order to examine the real situation the determination of residue sulphite levels in ready-to-consume foods is required. The aim of this paper is to assess the actual sulphite content of diets obtained from a combination of realistic meals high in sulphite-containing foods. Food products available in Italy containing added sulphites were identified. Overall, 211 samples of foods and beverages (including 85 samples of wine) were collected. The determination of sulphite residues was carried out on the foods which were prepared according to normal domestic practice. It was shown that the diets obtained from these foods would lead to an intake of 23 mg/day in children and 50 mg/day in adults (both slightly above the ADI for respectively a 30 kg child and a 60 kg adult). Among all sulphite-containing foods, the highest contributors to the intake were dried fruit and wine, both ingested without further treatment. The analysis of specific consumption data confirmed the existence of a risk of exceeding the ADI related to sulphite residue levels in wine.

Adult↗
PubMed2000

Junctional rhythm during slow pathway radiofrequency ablation in patients with atrioventricular nodal reentrant tachycardia: beat-to-beat analysis and its prognostic value in relation to electrophysiologic and anatomic parameters.

INTRODUCTION: Junctional rhythm usually is considered a sensitive but nonspecific marker of successful ablation of the slow pathway in AV nodal reentrant tachycardia. Nevertheless, this junctional rhythm has been little studied, and its relations to recognized predictors of successful radiofrequency (RF) application were never established in any study. METHODS AND RESULTS: Thirty-nine patients underwent RF ablation of the slow pathway for AV nodal reentrant tachycardia. Ninety RF applications were delivered, and each ablation site was determined using three different fluoroscopic projections. Six anatomic zones were defined from low posterior septum to the site of distal His-bundle recording (P1, P2, M1, M2, A1, and A2). Characteristics of junctional rhythm during RF applications were analyzed. Atrial electrogram characteristics at the ablation sites also were studied. All patients had successful slow pathway ablation, without any complication. The ablation sites were located as follows: 41 at P1, 26 at P2, 20 at M1, and 3 in M2. Forty RF applications were successful: 14 of 41 attempts at P1, 7 of 26 at P2, 16 of 20 at M1, and 3 of 3 at M2. Mid-septal ablation site (M1 and M2) was associated with higher occurrence of junctional rhythm (P < 0.0001), earlier first junctional beat (P = 0.008), and earlier occurrence of the longest junctional burst (P = 0.03) compared with posterior ablation site (P1 and P2). The combination of a mid-septal ablation site and a first junctional beat occurring < or = 3 seconds after onset of RF application identified successful RF application with 100% accuracy. Using multivariate analysis, the ablation site, duration of atrial electrogram (including slow pathway potential when present), and occurrence of junctional rhythm were independent predictors of success. CONCLUSION: Successful slow pathway ablation depends on many factors. Junctional rhythm characteristics are related to the site of RF delivery and can be helpful in assessing successful slow pathway ablation.

Adolescent↗
PubMed2000

Long-term effects of biatrial synchronous pacing to prevent drug-refractory atrial tachyarrhythmia: a nine-year experience.

INTRODUCTION: Results of previous studies suggest that atrial resynchronization by multisite atrial pacing may contribute to prevention of recurrences in patients with drug-refractory atrial tachyarrhythmias and significant intra-atrial conduction delay. METHODS AND RESULTS: To verify this hypothesis, a prospective noncontrolled study of 86 patients (mean age 66 +/- 10 years) was conducted in a single center between January 1989 and February 1998. Inclusion criteria were P wave duration > or = 120 msec with interatrial conduction time > or = 100 msec, and history of multiple recurrences of atrial tachyarrhythmias (mean 7 +/- 4.8 episodes) evolving in a persistent mode for at least 6 months despite optimized drug treatment (mean 2.7 +/- 1.8 drugs/patient). Patients were chronically implanted with a pacing system that ensured permanent biatrial pacing using two atrial leads, one placed in the high right atrium and the other one into the mid or the distal part of the coronary sinus. P wave duration decreased from a mean value of 187 +/- 29 msec before implant to 106 +/- 14 msec (P < 0.0001) under biatrial pacing. After a 33-month mean follow-up (range 6 to 109), 55 patients (64%) remained in sinus rhythm, including 28 patients (32.6%) without any documented recurrence and 27 patients with one or more recurrences in a paroxysmal or in a persistent form. In these 55 patients, drug treatment was significantly reduced in relation to the preimplantation period (1.4 +/- 0.6 vs 1.7 +/- 0.5 drugs/patient; P = 0.011). The other 31 patients went into chronic atrial arrhythmia after a mean period of 26 months. The only predictive factor of positive response was a spontaneous P wave duration < 160 msec at baseline. CONCLUSION: The results are consistent with a preventive effect of permanent biatrial pacing on recurrent and drug-refractory atrial arrhythmias associated with intra-atrial conduction delay.

Adult↗
PubMed2000

Na(+)-K(+)-ATPase alpha(2)-isoform expression in guinea pig hearts during transition from compensation to decompensation.

Disturbance in ionic gradient across sarcolemma may lead to arrhythmias. Because Na(+)-K(+)-ATPase regulates intracellular Na(+) and K(+) concentrations, and therefore intracellular Ca(2+) concentration homeostasis, our aim was to determine whether changes in the Na(+)-K(+)-ATPase alpha-isoforms in guinea pigs during transition from compensated (CLVH) to decompensated left ventricular hypertrophy (DLVH) were concomitant with arrhythmias. After 12- and 20-mo aortic stenosis, CLVH and DLVH were characterized by increased mean arterial pressure (30% and 52.7%, respectively). DLVH differed from CLVH by significantly increased end-diastolic pressure (34%), decreased sarco(endo)plasmic reticulum Ca(2+)-ATPase (-75%), and increased Na(+)/Ca(2+) exchanger (25%) mRNA levels and by the occurrence of ventricular arrhythmias. The alpha-isoform (mRNA and protein levels) was significantly lower in DLVH (2.2 +/- 0.2- and 1. 4 +/- 0.15-fold, respectively, vs. control) than in CLVH (3.5 +/- 0. 4- and 2.2 +/- 0.13-fold, respectively) and was present in sarcolemma and T tubules. Changes in the levels of alpha(1)- and alpha(3)-isoform in CLVH and DLVH appear physiologically irrelevant. We suggest that the increased level of alpha(2)-isoform in CLVH may participate in compensation, whereas its relative decrease in DLVH may enhance decompensation and arrhythmias.

Adaptation, Physiological↗
PubMed2000

[Cardiac insufficiency: prevention of ventricular arrhythmias].

Ventricular arrhythmias are particularly common in cardiac failure and their mechanisms are very complex. The prevention of these ventricular arrhythmias is only worthwhile if it results in benefits in terms of reduction of the risk of sudden death and in improvement in life expectancy. However, the relationship between complex ventricular arrhythmias and sudden death is far from established. The first problem is, therefore, to select the patients at high risk of sudden death. Unfortunately, there are no reliable markers of arrhythmic risk; only patients at low risk can be reasonably well identified on clinical and haemodynamic assessment and the results of ambulatory and signal averaged ECG. When an antiarrhythmic treatment seems to be required, the choice is very limited in practice. There is no role for Class I antiarrhythmics to play in this indication. Amiodarone, with its complex electrophysiological profile enabling an interaction with all potential mechanisms of ventricular arrhythmias, is a first-line drug in cardiac failure because of its efficacy and good myocardial tolerance. However, the benefits of amiodarone therapy in terms of reduction of global mortality have not been demonstrated, especially in view of the discordance between the results of the GESICA and CHF STAT trials. On the other hand, the value of betablockers, whether conventional molecules like bisoprolol (CIBIS II study) or metoprolol (MERIT-HF study), or molecules with a special profile such as carvedilol, has been clearly established. In association with conventional diuretics and angiotensin converting enzyme inhibitors, they reduce global mortality by about 35% and sudden death by 40%. However, the future possibly lies with non-pharmacological approaches such as the implantable defibrillator, at least in patients clearly identified as being at high risk of arrhythmic death, resuscitated from cardiorespiratory arrest due to documented ventricular fibrillation or presenting with haemodynamically poorly tolerated ventricular tachycardia. The automatic defibrillator could improve the prognosis of these patients, irrespective of their functional status (NYHA, Classes I, II or III). In practice, "rhythmological" management of cardiac failure cannot be dissociated from the haemodynamic and neuro-hormonal aspects of the affection, and only a multi-factorial approach is being realistic.

Anti-Arrhythmia Agents↗
PubMed2000

Articular fractures of the fingers in children.

Articular fractures of the fingers in children may result in severe sequelae that impair function of the hand. All displaced fractures must be reduced and fixed. Undisplaced fractures must be securely immobilized (including neighboring joints) and checked frequently for a possible displacement. Even when tested properly, articular fractures may have an unsatisfactory outcome.

Child↗
PubMed1999

Electrocardiographic predictive factors of long-term clinical improvement with multisite biventricular pacing in advanced heart failure.

Biventricular pacing has recently been proposed for treating patients with drug refractory heart failure and intraventricular conduction delay. The purpose is to restore ventricular relaxation and contraction sequences as homogeneously as possible. The aim of this study was to determine if some factors could predict the long-term clinical effectiveness of that new treatment. This study included 26 patients, aged 66 +/- 7 years, with drug refractory heart failure and wide QRS. Patients were implanted with a biventricular pacemaker. The left ventricle was paced through a coronary sinus tributary. New York Heart Association functional class, exercise tolerance, and left ventricular (LV) ejection fraction were collected at baseline and after pacemaker implantation. Patients were divided into 2 groups: group I = responders; group II = nonresponders. QRS duration and axis at baseline and during biventricular pacing, interventricular conduction time, and LV and right ventricular lead positions were compared between the 2 groups. Group I patients (n = 19) had a mean reduction of 1.3 in functional class and an increase in peak oxygen consumption rate by a mean of 50%. The only parameter that differed between the 2 groups was the QRS duration during biventricular pacing, with a significantly shorter value in group I than in group II (154 +/- 17 vs 177 +/- 26 ms; p = 0.016). Thus, a positive response to biventricular pacing is correlated with the quality of electrical resynchronization. The optimal positions of the right and LV leads would be those that could induce the greatest shortening of QRS duration.

Aged↗
PubMed1999

Optimal right ventricular pacing site in chronically implanted patients: a prospective randomized crossover comparison of apical and outflow tract pacing.

OBJECTIVES: To evaluate the long-term functional and hemodynamic effects of right ventricular outflow tract (RVOT) pacing by comparison with right ventricular apical (RVA) pacing. BACKGROUND: Acute studies have suggested that RVOT pacing could significantly improve cardiac performance in comparison with RVA pacing but no data are available in chronically implanted patients. METHODS: Sixteen patients with chronic atrial tachyarrhythmia and complete AV block were included. Left ventricular ejection fraction (LVEF) was > or =40% in ten and <40% in six. Patients were implanted with a standard DDDR pacemaker connected to two ventricular leads. A screw-in lead was placed at the RVOT and connected to the atrial port. A second lead was positioned at the RVA and connected to the ventricular port. Right ventricular outflow tract and RVA pacing was achieved by programming either the AAIR or the VVIR mode respectively. Four months later patients were randomized so as to undergo either RVOT or RVA pacing for three months according to a blind crossover protocol. Apart from the pacing mode, programming remained unchanged throughout the study. At the end of each period, NYHA class, LVEF, exercise time and maximal oxygen uptake were assessed. RESULTS: No significant difference was observed between the two modes for all the parameters analyzed. These identical results were observed in all patients globally, in patients with LVEF > or =40% as in those with LVEF <40%. CONCLUSIONS: Within the limits of this study, no symptomatic improvement or hemodynamic benefit was noted after three months of RVOT pacing, by comparison with RVA pacing.

Aged↗
PubMed1999

Patterns of food and nutrient intakes in Italy and their application to the development of food-based dietary guidelines.

Patterns of food and nutrient intakes in Italy were estimated starting from a nationwide food survey carried out by the National Institute of Nutrition (NIN) in 1994-6, called INN-CA 1995. The present analysis looks at food and nutrient intakes of the subsample of the adults (18-60-year-old individuals). In particular, the two extreme quartiles of the distribution of total fat intake expressed as percentage of energy were considered in the analysis. The results showed that the subjects included in the fourth quartile (high-fat consumers) consumed fewer vegetables than the subjects in the first quartile (low-fat consumers). Furthermore, high-fat consumers had a tendency to have an unbalanced diet, whereas the low-fat consumers present a better pattern. In synthesis, 50% of the adults reach the goal of at least 400 g of vegetables and fruit daily, and 25% consume less than 30% of energy from total fats. Convincing that part of the population whose diet does not comply with dietary goals to come back to the Mediterranean tradition might be a priority for nutrition education in Italy.

Adolescent↗
PubMed1999

Effects of permanent dual-chamber pacing on mitral regurgitation in hypertrophic obstructive cardiomyopathy.

AIMS: To assess the effects of chronic dual-chamber pacing on mitral regurgitation in hypertrophic obstructive cardiomyopathy. METHODS AND RESULTS: Twenty-three patients with hypertrophic obstructive cardiomyopathy and mitral regurgitation. treated with DDD pacing for 16 +/- 14 months, were included in the study. Mitral regurgitation was assessed by Doppler-echocardiography using semi-quantitative analysis (grades I-IV) and by measuring the maximum regurgitant jet area/left atrial area ratio. At the end of follow-up, DDD pacing reduced the outflow gradient from 93 +/- 37 mmHg to 31 +/- 30 mmHg (P<0.0001). Nine of the 14 patients who initially had > or =grade II mitral regurgitation improved by at least one grade, two of them exhibiting dramatic improvement (from grade IV and III to grade I). The regurgitant jet area/left atrial area ratio was reduced with DDD pacing from 20 +/- 13% to 11 +/- 6% (P<0.0001). Patients who had significant mitral regurgitation despite pacing were those whose outflow gradient remained high or those with mitral valve organic abnormalities (mitral annulus calcification or mitral valve prolapse). In the absence of organic abnormalities other than leaflet elongation, there was a significant correlation between the gradient value achieved with DDD pacing and the extent of mitral regurgitation (P<0.05). CONCLUSION: In the absence of organic mitral valve abnormalities, DDD pacing reduces in parallel mitral regurgitation and left ventricular outflow gradient. In such patients therefore, significant mitral regurgitation is not a contraindication to pacing.

Adult↗
PubMed1999

[The interosseous palmaris muscle of the thumb. Results of an anatomic study of a muscle of the first ray].

In sixteen of twenty adult human cadaveric hands a muscle fascicle was isolated from the adductor pollicis muscle. It had osseous origins from the base of the first metacarpal bone and from the trapezium bone in eleven hands. These origins were connected by a fibrous arch, which was a soft tissue origin itself. In two of the sixteen hands, muscle fibers emerged from the palmar aspect of the first dorsal interosseous muscle near the radial artery. The findings can be explained by the ontogenesis of the human hand. The described muscle is neither a part of the oblique head of the adductor pollicis nor an equivalent to the three palmar interosseous muscles. In our dissections it was a constant muscle. Other studies have to show the exact function of the muscle. We postulate a stabilization of the carpometacarpal joint of the thumb.

Adult↗
PubMed1999

Intake of saccharin, aspartame, acesulfame K and cyclamate in Italian teenagers: present levels and projections.

The intake of saccharin, aspartame, acesulfame K and cyclamate was assessed in 212 Italian teenagers aged 13-19 in 1996. Total daily intake of intense sweeteners was assessed on the basis of dietary records (14 consecutive days). The sweetener content of sugar-free products (soft drinks, candies, chewing gums, yoghurts, jam and table-top sweeteners) was provided by manufacturers. Sugar-free products were consumed by 77% of the subjects. Mean daily intake among consumers was 0.24 mg/kg body weight (bw) for cyclamate (13 subjects), 0.21 mg/kg bw for saccharin (9 subjects), 0.03 mg/kg bw for aspartame (162 subjects), and 0.02 mg/kg bw for acesulfame K (56 subjects). No subject exceeded the ADI (Acceptable Daily Intake) of an intense sweetener. Projections based on the present levels of use of intense sweeteners in sugar-free products and on the dietary pattern observed in the sample suggest that approaching the ADI could be possible only if subjects with high intakes of both soft drinks and table-top sugar substituted these items with respectively sugar-free beverages and table-top sweeteners containing either saccharin or cyclamate.

Adolescent↗