25 research outputs found
Psychometric Properties of the Physical Activity Questionnaire for Older Children in Italy: Testing the Validity among a General and Clinical Pediatric Population.
The purpose of this research was to assess an Italian version of the Physical Activity Questionnaire for Older Children (PAQ-C-It). Three separate studies were conducted, whereby testing general psychometric properties, construct validity, concurrent validity and the factor structure of the PAQ-C-It among general and clinical pediatric population. Study 1 (n = 1170) examined the psychometric properties, internal consistency, factor structure (exploratory factor analysis, EFA) and construct validity with enjoyment perception during physical activity. Study 2 (n = 59) reported on reliability, construct validity with enjoyment and BMI, and on cross-sectional concurrent validity with objectively measured MVPA (tri-axial accelerometry) over the span of seven consecutive days. Study 3 (n = 58) examined the PAQ-C-It reliability, construct validity with BMI and VO2max as the objective measurement among a population of children with congenital heart defects (CHD). In study 2 and 3, the factor structure of the PAQ-C-It was then re-examined with an EFA. The PAQ-C-It showed acceptable to good reliability (alpha .70 to .83). Results on construct validity showed moderate but significant association with enjoyment perception (r = .30 and .36), with BMI (r = -.30 and -.79 for CHD simple form), and with the VO2max (r = .55 for CHD simple form). Significant concurrent validity with the objectively measured MVPA was reported (rho = .30, p < .05). Findings of the EFA suggested a two-factor structure for the PAQ-C-It, with items 2, 3, and 4 contributing little to the total score. This study supports the PAQ-C-It as an appropriate instrument to assess the MVPA levels of Italian children, including children with simple forms of CHD. Support is given to the possible instrument effectiveness on a large international perspective in order to level out data gathering across the globe
Nicotine administration stimulates the in vivo N-methyl-D-aspartate receptor/nitric oxide/cyclic GMP pathway in rat hippocampus through glutamate release
1. The in vivo effects of nicotine on the nitric oxide (NO) synthase/cyclic GMP pathway of the adult rat hippocampus have been investigated by monitoring the levels of extracellular cyclic GMP during microdialysis in conscious unrestrained animals. 2. Intraperitoneal (i.p.) administration of nicotine caused elevation of cyclic GMP levels which was prevented by mecamylamine. The effect of nicotine was abolished by local infusion of the NO synthase inhibitor N(G)-nitro-L-arginine (L-NOARG) or by the soluble guanylyl cyclase blocker 1H-[1,2,4]oxadiazolo[4,3-a]quinoxaline-1-one (ODQ). 3. Local administration of the NMDA receptor antagonists cis-4-(phosphonomethyl)-2-piperidinecarboxylic acid (CGS19755) and dizocilpine (MK-801) inhibited by about 60% the nicotine-induced elevation of cyclic GMP. Nicotine was able to stimulate cyclic GMP outflow also when administered directly into the hippocampus; the effect was sensitive to mecamylamine, L-NOARG, ODQ or MK-801. 4. Nicotine, either administered i.p. or infused locally, produced augmentation of glutamate and aspartate extracellular levels, whereas the outflows of γ-aminobutyric acid (GABA) and glycine remained unaffected. Following local administration of high concentrations of nicotine, animals displayed symptoms of mild excitation (sniffing, increased motor and exploratory activity) during the first 20–40 min of infusion, followed by wet dog shake episodes; these behavioural effects were prevented by mecamylamine or MK-801, but not by L-NOARG or by ODQ. 5. It is concluded that (a) nicotine stimulates the production of NO and cyclic GMP in the hippocampus; (b) this occurs, at least in part, through release of glutamate/aspartate and activation of NMDA receptors. Modulation of the NMDA receptor/NO synthase/cyclic GMP pathway may be involved in the cognitive activities of nicotine
Exercise and inflammatory bowel disease : immunological aspects
Effet de l'activité physique d'intensité modérée chez des sujets atteints d'affections intestinales inflammatoires : rectocolite hémorragique et maladie de Crohn. Effets sur les symptômes, sur le temps de transit intestinal, sur la perméabilité des parois intestinales. Effets immunitaires de l'exercice, effets sur l'activation de la fonction neutrophile, rôle dans la prévention des maladies de l'intestin d'après l'étude des données épidémiologiques, incidences sur l'état de santé et la qualité de vie des malades entre les crises inflammatoires ou après des interventions chirurgicales de résection d'une partie de l'intestin
Serum IGF-I, IGFBP-3, and IGFBP-2 levels during acute and Chronic high altitude exposure
J Endocrinol Invest 21, Suppl. to n\ub0 7: 155, 199
Blunted growth hormone response to maximal exercise in middle-aged versus young subjects and no effect of endurance training
The purpose of this study was to evaluate the GH response to exercise and the effects of endurance training on this response in early middle-aged men. Seven healthy middle-aged [M; 42.0 \ub1 2.4 (\ub1sd) yr old] and five young (Y; 21.2 \ub1 1.1 yr old) competition cyclists were investigated before and after 4 months of intensive endurance training. Subjects performed an exhaustive incremental exercise test (50 watts for 3 min) with gas exchange measurement, and blood samples for lactate, glucose, and GH determinations were drawn before exercise, at the end of the exercise, and in the recovery phase (1, 3, 5, 10, 15, 20, and 30 min). Basal insulin-like growth factor I was also determined. At exhaustion no differences were found in relative maximal heart rate or blood lactate and glucose peaks. On the contrary, the two groups had markedly different GH responses; in fact, the peak GH response to exhaustive exercise was much lower in M than in Y (8.1 \ub1 1.3 vs. 57.1 \ub1 15.5 \u3bcg/L; P < 0.01). The training, similar in subjects of the same group, increased progressively from 182 to 300 km/week (+64.8%) in M and from 350 to 600 km/week (+71.4%) in Y.
After the training, the percent increase in maximal oxygen consumption was similar in the two groups (M, +15.2%; Y, +17.5%), confirming that the efficiency of the training performed was comparable. In neither group did training have any effect on the GH peak response to exercise, confirming the blunted GH response in M compared to Y (6.7 \ub1 1.0 vs. 61.0 \ub1 12.9 \u3bcg/L; P < 0.01). Similarly, insulin-like growth factor I concentrations were not significantly affected by training.
In conclusion, active middle-aged subjects, compared with the young, showed a blunted GH response to a physiological stimulus such as exercise, indicating that the age-related decline in GH secretion appears in early middle age. This response was not modified by training in either early middle-aged or young subjects
Decreased serum leptin levels during prolonged high altitude exposure
Circulating leptin concentrations are shown to be influenced not only by hormones, but also by body weight and energy balance. High altitude (HA) exposure induces a daily negative energy balance and stress hormone activation. The aim of our study was to evaluate leptin concentration during both acute and prolonged HA exposure and its correlations with some metabolic and hormonal parameters. Twelve males were studied during a stay at HA (15–20 days at 5,050 m). Blood samples for serum leptin, plasma insulin and 24-h urinary epinephrine (E) and norepinephrine (NE) were collected at sea level (SL), at the arrival at HA (A) and after 12–16 days (C) of stay. Symptoms of Acute Mountain Sickness (AMS) were evaluated using the Lake Louise score and the results showed there was no relationship with leptin concentrations. During the stay, both body mass index and leptin levels significantly decreased in both groups [leptin from 1.88 (1.12) to 1.21 (1.04) ng/ml, P<0.008, in A; and to 1.06 (0.74) ng/ml, P<0.003, in C]. Acute HA exposure induced a clear-cut significant increase of NE (P<0.001 in A, P<0.003 in C) while E and insulin levels were unchanged in both phases. Moreover, a significant correlation between leptin and NE absolute values, and leptin and insulin variations was found (r 0.359, P<0.034 and r=0.560, P<0.007, respectively). Exposure to HA induces a decrease in fasting serum leptin concentrations in men. These changes are not linked to symptoms of AMS but to hormonal and energy balance variations, suggesting that leptin is involved in the endocrine and metabolic adaptations occurring during HA exposure
Coronary CT angiography in asymptomatic middle-aged athletes with ST segment anomalies during maximal exercise test
The clinical significance of ST segment anomalies occurring during exercise test in asymptomatic subjects is still debated. We designed a cross-sectional study to evaluate if the presence of these exercise test abnormalities were related with coronary CT angiography findings. Nine hundred forty athletes (range 30 to 60 years old), performed a maximal exercise test for sport eligibility. Forty-six subjects (4.9%) showing ST abnormalities during exercise and/or the recovery phase were referred to a 64-slice coronary computed tomography (CT) angiography. Among 44 subjects who underwent coronary CT angiography, 23 had an equivocal while 21 had a positive exercise test. Coronary CT angiography found, six and eight subjects with significant and not significant coronary artery disease, respectively. Further, seven patients demonstrated origin and course coronary anomalies. The positive predictive value for significant coronary artery disease of the exercise test was 13.6%. Our data suggest the referral to coronary CT angiography even of patients with equivocal repolarization anomalies during exercise and its recovery phase. Although the positive predictive value of a maximal exercise test in asymptomatic athletes appears lower than what observed in patients at high risk for coronary artery disease, about half of athletes with equivocal or positive exercise test demonstrated some coronary abnormalities
Effetti della somministrazione di arginina e piridostigmina sulla risposta del GH all'esercizio massimale in soggetti di media et\ue0\ua0
Coronary CT In Asymptomatic Subjects With VentricularRepolarization Abnormalities During Maximal Exercise Test
ABSTRACT: Specific data are still lacking about the significance of repolarization abnormalities
observed during exercise test in physically active asymptomatic subjects. Coronary
CT is a highly sensitive diagnostic procedure able to confirm or exclude a significant
coronary artery disease (CAD).
PUR POSE : To evaluate if the occurrence in asymptomatic subjects of ECG
repolarization abnormalities potentially suggesting a CAD, is confirmed by coronary
CT. Further, clarify if the likelihood of detecting CAD or coronary anomalies was
related to the degree of the ECG abnormalities and to the prevalence of cardiovascular
risk factors.
MET HODS: Among 940 athletes performing a maximal exercise test for sport
eligibility (age 30-60yrs), 44 asymptomatic subjects (4,7%, 39 men and 5 females,
45,2\ub17,1yrs) demonstrated repolarization abnormalities requiring the completion of
a coronary CT. The exercise tests were classified into two categories: suspicious and
positive for CAD.RESU LTS : The average maximal heart rate at exhaustion was 170,4\ub111,9. Risk
factors evaluation demonstrated 10 subjects with hypertension, 23 subjects with
hypercholesterolemia, 5 smokers. Among the 44 subjects 23 had a suspicious while 21
had a positive exercise test. The coronary CT demonstrated 6 subjects (13,6%) with a
clinically significant CAD, 8 non-significant CAD, while 7 showed various coronary
abnormalities. Considering the coronary CT as \u201cgold standard\u201d, the positive predictive
value (PPV) of the exercise test for any coronary anomaly was 61,9% for positive
exercise tests (47,7% including suspicious tests), while the PPV of positive tests for
CAD was 47,6% (31,8% including suspicious tests). The association of late recovery
abnormalities and cardiovascular risk factors improved the likelihood of CAD.
CON CLUSION : Our data suggest the clinical importance of slight repolarization
abnormalities occurring at the peak of the exercise in asymptomatic middle-aged
athletes, particularly when associated with the presence of cardiovascular risk factors.
They also support the importance of a prolonged ECG monitoring during the late
recovery phase. The PPV of a maximal exercise test in asymptomatic athletes appears
lower than what observed in symptomatic subjects, however, about half of these
subjects demonstrated some coronary anomalies