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A Pietrobelli

Publications and source records attributed to A Pietrobelli.

At least 55 records · Page 3Linked to original sources
PubMed2002

Mite avoidance can reduce air trapping and airway inflammation in allergic asthmatic children.

BACKGROUND: We investigated the effects of prolonged allergen avoidance in 18 house dust mite-sensitized asthmatic children during a prolonged residential period at a high altitude, allergen-free environment. METHODS: Evaluations of residual volume (RV) and exhaled nitric oxide (eNO) were performed (i) at admission to the residential house in September, (ii) in December after 3 months of stay, (iii) in January after 15 days at home, exposed to allergens, and (iv) in June after 9 months of stay. RESULTS: During the study period RV showed a significant decrease in December (from 117.5 +/- 7.7% to 96.5 +/- 3.2%) (P < 0.02) and a following increase in January (126.2 +/- 17.2%), after allergen re-exposure (P < 0.03). RV decreased again in June at the end of the study period (91.1 +/- 6.0%) (P = 0.001). FEV(1), FEF(25-75) and VC values did not present significant variations. ENO showed a significant decrease in December after 3 months at high altitude (from 21.3 +/- 3.9 p.p.b. to 11.9 +/- 1.7 p.p.b.) (P = 0.03), but no further significant change. No correlation was found between lung volumes and eNO, probably reflecting different aspects of asthma. CONCLUSIONS: Results suggest that RV may be more sensitive than other respiratory function parameters in identifying children with air trapping, being influenced significantly as the inflammatory indices by effective allergen avoidance/exposure regimen.

Adolescent↗
PubMed2002

New bioimpedance model accurately predicts lower limb muscle volume: validation by magnetic resonance imaging.

Conventional bioimpedance analysis (BIA) methods now simplify the representation of lower limb geometry and electrical properties for body composition estimation. In the present study, a three-dimensional model of the lower limb was assembled by segmentation of magnetic resonance cross-sectional images (MRI) for adipose tissue, skeletal muscle, and bone. An electrical network was then associated with this model. BIA and MRI measurements were made in six lean subjects (3 men and 3 women, age 32.2 +/- 6.9 yr). Assuming 0.85 S/m for the longitudinal conductivity of the muscle, the model predicted in the examined subjects an impedance profile that conformed well to the BIA impedance profile; predicted and measured resistances were similar (261.3 +/- 7.7 vs. 249 +/- 9 Omega; P = not significant). The resistance profile provided, through a simpler model, muscle area estimates along the lower limb and total leg muscle volume (mean 4,534 cm(3) for men and 4,071 cm(3) for women) with a mean of the absolute value of relative error with respect to MRI of 6.2 +/- 3.9. The new approach suggests that BIA can reasonably estimate the distribution and volume of muscles in the lower extremities of lean subjects.

Adipose Tissue↗
PubMed2002

The combination of single-dose montelukast and loratadine on exercise-induced bronchospasm in children.

The aim of the study was to evaluate the protective effect of single-dose, combination treatment comprising montelukast (5 mg) and loratadine (10 mg), on exercise-induced bronchoconstriction in asthmatic children. The combination was compared to placebo, loratadine and montelukast alone. Nineteen children were enrolled in a double-blind randomised, single-dose, crossover study. For each treatment patients undertook two treadmill exercise tests, 2 and 12 h respectively after single-dose administration. No significant differences were seen in the maximum fall in forced expiratory volume in one second (FEV1) 2 h after treatment and placebo. Whereas significant differences in maximum fall in FEV1 were observed between treatment groups 12 h after administration. Loratadine alone did not show any significant protection or any additional effect in comparison with montelukast alone. Single doses of montelukast and montelukast plus loratadine were significantly more effective than loratadine at 12 h. The present study, performed using single-dose treatments, demonstrated that maximal protective effect by montelukast was obtained 12 h after dosing and that montelukast plus loratadine did not result in significant additive bronchoprotective effects on exercise-induced bronchoconstriction.

Acetates↗
PubMed2001

Waist circumference and cardiovascular risk factors in prepubertal children.

OBJECTIVE: Intra-abdominal fat has been identified as being the most clinically relevant type of fat in humans. Therefore, an assessment of body-fat distribution could possibly identify subjects with the highest risk of adverse lipid profile and hypertension. Few data on the relationship between body-fat distribution and cardiovascular risk factors are available in children, especially before puberty. RESEARCH METHODS AND PROCEDURES: This cross-sectional study was undertaken to explore the relationship between anthropometric variables, lipid concentrations, and blood pressure (BP) in a sample of 818 prepubertal children (ages 3 to 11 years) and to assess the clinical relevance of waist circumference in identifying prepubertal children with higher cardiovascular risk. Height, weight, triceps and subscapular skinfolds, waist circumference, and BP were measured. Plasma levels for triacylglycerol, total cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein cholesterol, apolipoprotein A1 (ApoA1), and apolipoprotein B (ApoB) were determined. RESULTS: Females were fatter than males (5.8 [3.5] vs. 4.8 [3.3] kg of fat mass; p < 0.01). Males had higher HDL cholesterol and ApoA1/ApoB plasma concentrations than females (p < 0.001 and p < 0.01, respectively). Waist circumference had a higher correlation with systolic and diastolic BP (r = 0.40 and 0.29, respectively; p < 0.001) than triceps (r = 0.35 and 0.21, respectively; p < 0.001) and subscapular (r = 0.28 and 0.16, respectively; p < 0.001) skinfolds and relative body weight (0.33 and 0.23, respectively; p < 0.001). Multivariate linear model analysis showed that ApoA1/ApoB, HDL cholesterol, total cholesterol/HDL cholesterol, and systolic as well as diastolic BP were significantly associated with waist circumference and triceps and subscapular skinfolds, independently of age, gender, and body mass index. DISCUSSION: Waist circumference as well as subscapular and triceps skinfolds may be helpful parameters in identifying prepubertal children with an adverse blood-lipids profile and hypertension. However, waist circumference, which is easy to measure and more easily reproducible than skinfolds, may be considered in clinical practice. Children with a waist circumference greater than the 90th percentile are more likely to have multiple risk factors than children with a waist circumference that is less than or equal to the 90th percentile.

Abdomen↗
PubMed2001

Is body mass index a measure of adiposity in elderly women?

OBJECTIVE: To evaluate the accuracy of body mass index (BMI) as a predictor of body fat in elderly women. RESEARCH METHODS AND PROCEDURES: A total of 1423 women aged 67 +/- 5 (mean +/- SD, range: 60 to 88) years were consecutively enrolled into the study. Fat mass (FM) was measured using DXA. RESULTS: BMI explained 72.9% of FM variance (p < 0.0001), with a root mean square error of estimate (RMSE) of 3.5 kg. After standardization of RMSE on the dependent variable as RMSE%, the prediction error equaled 15%. BMI explained 54.8% of FM% variance (p < 0.0001), with an RMSE of 4.1%, corresponding to an RMSE% of 11%. DISCUSSION: The relatively high RMSE% of the FM and FM%-BMI associations caution against the use of BMI as an adiposity index in individual elderly women. However, an error corresponding to 11% of FM% may be accepted for population studies of body fat in elderly women.

Absorptiometry, Photon↗
PubMed2001

Multi-component body composition models: recent advances and future directions.

OBJECTIVE: This overview examines concepts related to a category of body composition methods generally referred to as multi-component models, that is, those models that include three or more components. We summarize the rationale for, applications, and types of multi-component models along with sources of error. Our review presents the strengths and limitations of available models and identifies important future research directions.

Body Composition↗
PubMed2001

Does waist circumference predict fat gain in children?

OBJECTIVE: The aim of this study was to identify in a group of 8-y-old prepubertal children the anthropometric parameter with the highest prediction power of overweight, measured 4 y later. SUBJECTS: One-hundred and twelve Caucasian children (54 males, 58 females), aged 8.7+/-0.9 y, were studied. RESULTS: An analysis of the association between relative body mass index (BMI) at follow-up (%) and some indexes of adiposity like relative BMI (%), waist circumference, subscapular and triceps skinfolds, the sum of four skinfolds and percentage fat mass measured at baseline, showed that relative BMI (relBMI) at baseline had the highest association with relBMI at follow-up (r=0.77; P<0.001); waist circumference had a slightly lower significant association with relBMI at follow-up (r=0.74; P<0.001). In a multiple regression analysis, waist circumference (adjusted for age) accounted for approximately 64% of the variation of relBMI at follow-up (P<0.001). RelBMI measured at baseline accounted for approximately 59% of the variation of relBMI at follow-up (P<0.001). Multiple logistic regression analysis included waist circumference, adjusted for age, mother's BMI and relBMI measured at baseline as independent variables in the final equation. In particular, each centimeter increase of waist circumference at the age of 8 y doubled the risk of having a relBMI greater than 120% at the age of 12 y. CONCLUSION: The results of this study, the first which has approached this investigation in children, showed that waist circumference measured at the age of 8 y, which is simple to perform and easy to reproduce, may be a promising index to assess adiposity as well as to predict overweight at puberty.

Adipose Tissue↗
PubMed2001

Sexual dimorphism in circulating leptin concentrations is not accounted for by differences in adipose tissue distribution.

BACKGROUND: Circulating concentrations of leptin normalized to total adipose tissue mass are significantly greater in females than in males. Rates of leptin expression (per gram of adipose tissue) are significantly greater in subcutaneous (SAT) than visceral (VAT) adipose tissue and the relative amount of fat stored as SAT vs VAT is significantly greater in pre-menopausal females than in males. Gender-related differences in the relative amounts of SAT and VAT may account for the greater circulating leptin concentration relative to fat-mass in females than males. METHODS: We examined body composition and anatomic fat distribution by dual energy X-ray-absorptiometry (DEXA) and magnetic resonance imaging (MRI), and post-absorptive circulating concentrations of leptin and insulin in 58 subjects (26 females, 32 males). Stepwise multiple linear regression analyses, treating gender as a dichotomous variable, were performed to determine inter-relationships among leptin concentrations and insulin concentrations, VAT and SAT. RESULTS: Body composition by DEXA and MRI were highly correlated (r(2)=0.97, P<0.0001). There were significant gender effects on leptin/total fat mass (males, 0.17+/-0.01 ng/ml/kg; females, 0.49+/-0.05 ng/ml/kg; P<0.0001) and relative amounts of fat in SAT and VAT depots (ratio of SAT/VAT; males, 12.3+/-1.5; females, 32.9+/-3.2; P<0.0001). Circulating leptin concentration was significantly correlated with insulin concentration (P=0.001), SAT (P<0.0001) and gender (P=0.033). Circulating concentrations of insulin were significantly correlated with VAT, but not SAT, in males and with SAT, but not VAT, in females. CONCLUSIONS: The sexual dimorphism in the relationship between leptin and adipose tissue mass cannot be explained by differences in the relative amounts of VAT and SAT. Thus, the sexual dimorphism in plasma leptin concentration appears to reflect, at least in part, effects of circulating concentrations of gonadal steroids (especially androgens) and/or primary genetic differences that are independent of amounts of VAT or SAT.

Absorptiometry, Photon↗
PubMed2001

Unreliable use of standard muscle hydration value in obesity.

Intramuscular water content is assumed to be constant in humans independent of their anthropometric characteristics. To verify whether this assumption is correct, intramuscular water, proteins, glycogen, and both total and intramyocytic triglycerides were measured in 51 samples of rectus abdominis muscle obtained from 16 lean and 35 overweight and obese subjects (body mass index cutoff 24.9 kg/m2). Data (referred to as wet tissue) were analyzed by means of a composition model at the cellular level of the skeletal muscle (SM). The average SM water content was 76.3 +/- 3.3% in normal-weight individuals and 65.7 +/- 5.8% in obese subjects (P < 0.0001). Total triglycerides were 5.5 +/- 2.3% in controls and 19.0 +/- 7.0% in obese subjects (P < 0.0001). The intramyocytic triglyceride fraction was also increased in obese subjects. The composition model provides an explanation for the negative correlation between total triglycerides and intramuscular water, and some of the model parameters were determined from the experimental data. In conclusion, although the hydration of fat-free SM mass may be unchanged in obese subjects, the hydration of in toto muscle mass decreases as its lipid content increases.

Adult↗
PubMed2001

Effects of contingent television on physical activity and television viewing in obese children.

OBJECTIVE: Elevated television (TV) viewing and physical inactivity promote obesity in children. Thus, changes in physical activity and sedentary behavior seem critical to treating childhood obesity. PRESENT STUDY: Using a randomized, 2-arm design, this pilot study tested the effects of contingent TV on physical activity and TV viewing in 10 obese children. TV viewing was contingent on pedaling a stationary cycle ergometer for experimental participants but was not contingent on pedaling for control participants. The study was conducted over 12 weeks, including a 2-week baseline period. RESULTS: Multivariate analyses indicated that the intervention significantly increased pedaling and reduced TV-viewing time. During the treatment phase, the experimental group pedaled 64.4 minutes per week on average, compared with 8.3 minutes by controls. The experimental group watched 1.6 hours of TV per week on average, compared with 21.0 hours per week on average by controls during this phase. Secondary analyses indicated that the experimental group showed significantly greater reductions in total body fat and percent leg fat. Total pedaling time during intervention correlated with greater reductions in percent body fat (r = -0.68). CONCLUSIONS: Contingencies in the home environment can be arranged to modify physical activity and TV viewing and may have a role in treating childhood obesity. Contingent TV may be one method to help achieve this goal.

Behavior Therapy↗
PubMed2000

Cat sensitivity: 7-yr audit in children attending a paediatric allergy clinic in North Italy.

Sensitivity to cats and exposure to cat allergen is a common cause of asthma exacerbation in children. To date, there is no data on the prevalence of cat sensitivity in children living in North Italy. Therefore, a 7-yr survey was performed in patients attending an allergy clinic for the first time. Skin prick tests (SPT) for perennial allergens and for pollens relevant to the region were performed in 4,957 children attending the outpatient clinic 1992-1998. A questionnaire on present or past cat ownership was presented to all cat-skin prick test positive children. An evaluation of cat ownership on the general population was made by telephone interview on a random sample of 1,268 families living in the same area. With a 3-mm wheal as a positive cut-off 439 (8.85%) children had a positive SPT to cats. Of these 103 (23.4%) had a cat at home and 336 (76.6%) never had a cat in the house. With a greater positive cut-off(a wheal diameter > or =4 mm) 140 (2.8%) showed a positive SPT to cats of these 35 (25%) had a cat at home and 105 (75%) had only an indirect exposure to the pet. Of the telephone interviewed families; 16% stated they had a cat at home. Cat sensitivity is less prevalent in Italy, in this hospital based population, compared with other European countries and this is in agreement with a lower rate of cat ownership. Cat sensitivity was three times more frequent in children who never had a cat at home, than in children living with cats, when the selected positive cut-off was either a wheal diameter of 3 mm or > or =4 mm. Thus in a population with a low prevalence of cat ownership public exposure seems to be more important than domestic exposure for the development of sensitivity.

Animals↗
PubMed1999

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Journal Article↗
PubMed1999

Body composition in children and adults by air displacement plethysmography.

OBJECTIVES: Air displacement plethysmography (ADP) may provide a partial alternative to body density (Bd) and therefore body composition measurement compared to conventional hydrodensitometry (Hd) in children. As there are no evaluation studies of ADP in children, this study had a two-fold objective: to compare Bd estimates by ADP and Hd; and to compare fat estimates by both ADP and Hd to fat estimates by another reference method, dual energy X-ray absorptiometry (DXA). SETTING: Obesity Research Center, St. Luke's/Roosevelt Hospital, New York, USA. SUBJECTS: One hundred and twenty subjects (66 females/54 males) who ranged in age from 6-86 y and in body mass index (BMI, kg/m2) from 14.1-40.0 kg/m2 met study entry criteria. STUDY DESIGN: Cross-sectional study of healthy children (age < or = 19 y) and adult group for comparison to earlier studies. Each subject completed ADP, Hd, and DXA studies on the same day. Only subjects with subjectively-judged successful Hd studies were entered into the study cohort. RESULTS: There was a high correlation between Bd by ADP and Hd (Bd Hd = 0.11 + 0.896 x Bd ADP; r = 0.93, SEE = 0.008 g/cm3, P < 0.0001), although the regression line slope and intercept differed significantly from 1 and 0, respectively. Additional analyses localized a small-magnitude Bd bias in the child (n = 48) subgroup. Both ADP and Hd %fat estimates were highly correlated (r > 0.9, P < 0.0001) with %fat by DXA in child and adult subgroups. Bland-Altman analyses revealed no significant %fat bias by either ADP or Hd vs DXA in either children or adults, although a bias trend (P = 0.11) was detected in the child subgroup. CONCLUSION: With additional refinements, the air displacement plethysmography system has the potential of providing an accurate and practical method of quantifying body fat in children as it now does in adults.

Absorptiometry, Photon↗
PubMed1999

Weight loss increases and fat loss decreases all-cause mortality rate: results from two independent cohort studies.

OBJECTIVE: In epidemiological studies, weight loss is usually associated with increased mortality rate. Contrarily, among obese people, weight loss reduces other risk factors for disease and death. We hypothesised that this paradox could exist because weight is used as an implicit adiposity index. No study has considered the independent effects of weight loss and fat loss on mortality rate. We studied mortality rate as a function of weight loss and fat loss. DESIGN: Analysis of 'time to death' in two prospective population-based cohort studies, the Tecumseh Community Health Study (1890 subjects; 321 deaths within 16y of follow-up) and the Framingham Heart Study (2731 subjects; 507 deaths within 8y of follow-up), in which weight and fat (via skinfolds) loss were assessable. RESULTS: In both studies, regardless of the statistical approach, weight loss was associated with an increased, and fat loss with a decreased, mortality rate (P < 0.05). Each standard deviation (s.d.) of weight loss (4.6 kg in Tecumseh, 6.7 kg in Framingham) was estimated to increase the hazard rate by 29% (95% confidence interval CI), (14%, 47%, respectively) and 39% (95% CI, 25%, 54% respectively), in the two samples. Contrarily, each s.d. of fat loss (10.0 mm in Tecumseh, 4.8 mm in Framingham) was estimated to reduce the hazard rate 15% (95% CI, 4%, 25%) and 17% (95% CI, 8%, 25%) in Tecumseh and Framingham, respectively. Generalisability of these results to severely (that is, body mass index BMI) > or = 34) obese individuals is unclear. CONCLUSIONS: Among individuals that are not severely obese, weight loss is associated with increased mortality rate and fat loss with decreased mortality rate.

Adipose Tissue↗
PubMed1999

An independent, inverse association of high-density-lipoprotein-cholesterol concentration with nonadipose body mass.

BACKGROUND: Increasing body mass index (BMI) is associated with progressively lower serum HDL-cholesterol concentrations, although the underlying body-composition compartment accounting for this unfavorable lipid change remains uncertain. OBJECTIVE: Because growing evidence favors a role of lean tissue in HDL homeostasis, the hypothesis was tested that non-adipose tissue components of body mass explain the inverse association of HDL cholesterol and BMI. DESIGN: Fasting serum lipid concentrations and body composition [total, subcutaneous, and visceral adipose tissue; adipose tissue-free mass (ATFM); and skeletal muscle by whole-body magnetic resonance imaging and body cell mass by 40K counting) were evaluated in healthy adults. Body-composition compartments were expressed as height2-normalized indexes. RESULTS: An inverse correlation was observed between serum HDL cholesterol and BMI in women (n = 68; R2 = 0.08, P = 0.023) and men (n = 61; R2 = 0.07, P = 0.046). Significant inverse correlations (P = 0.005-0.02) were also observed between HDL cholesterol and nonadipose components (ie, ATFM, skeletal muscle, and body cell mass) but not between HDL cholesterol and any adipose tissue component. The association between HDL cholesterol and ATFM remained significant after serum triacylglycerol was controlled for. When BMI was entered into the HDL cholesterol-ATFM regression model, BMI was not a significant independent variable. The strongest correlate of serum triacylglycerol was visceral adipose tissue (P = 0.002 for both women and men). CONCLUSIONS: Lean tissues and body cell mass appear to account in part for the long-observed inverse association of HDL cholesterol and BMI. These observations suggest a link between nonadipose tissue compartments and the greater cardiovascular risk associated with high BMI.

Adipose Tissue↗