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Biomedical subjects

P Lebecque

Publications and source records attributed to P Lebecque.

At least 37 records · Page 2Linked to original sources
PubMed2000

Gonadal steroids and bone metabolism in young castrated male rats.

At 45 days of age, 40 male Wistar rats were castrated, then randomly divided into four groups, S.C. injected for 60 days after surgery either with 17beta-estradiol (E) 10 microg/kg BW/48 hours, progesterone (P) 140 microg/kg BW/48 hours, dihydrotestosterone (D) 2 microg/kg BW/48 hours, E + P + D same doses, or solvent alone (CX). Ten other rats were sham-operated (SH) and used as controls. Animals were put in balance to determine Ca and phosphorus (Pi) intestinal apparent absorption (IA Ca, IA Pi) and urinary pyridinium crosslinks excretion. Plasma was collected for measurement of intact-parathyroid hormone (PTH), calcitonin (CT), insulin-like growth factor I (IGF-I), 1,25 dihydroxyvitamin D (1,25(OH)(2)D), Ca, and Pi. Orchidectomy induced marked seminal vesicles atrophy and increased plasma CT, PTH, and Ca concentrations. IA Ca was significantly higher in P rats, however, neither castration nor any other treatment had significant effects. Orchidectomy decreased femoral length, dry weight, and Ca content, whereas E or D given alone or together with P improved endochondral growth and enhanced femoral Ca content. Again, bone mineral density was lowered by orchidectomy and reestablished by both E and EPD, even above SH values, this effect being more important at the metaphyseal levels. Urinary pyridinium cross-links excretion and plasma osteocalcin concentrations were higher in the CX animals than in the controls. Although E and D given alone did reduce both biochemical turnover markers, they showed additive effect when given together (EPD). In conclusion, in the young castrated male rat, E was more efficient than D for preventing bone loss, the most important effect being induced by a combination of E+P+D.

Amino Acids↗
PubMed2000

Daidzein is more efficient than genistein in preventing ovariectomy-induced bone loss in rats.

We investigated the ability of genistein and daidzein, two soybean isoflavones, compared with that of 17 alpha-ethinylestradiol, to prevent bone loss in ovariectomized rats, a model for postmenopausal osteoporosis. Female Wistar rats (n = 65; 12 mo old) were either sham-operated (SH; n = 13) or ovariectomized (OVX; n = 52). On d 0, OVX rats were randomly assigned to groups as follows: 13 received genistein [G; 10 mcg/(g body weight. d)], 13 were treated with daidzein [D; 10 mcg/(g body weight. d)], 13 received 17 alpha-ethinylestradiol [E(2); 30 mcg/kg body weight. d)] and 13 were untreated (OVX). Compounds were mixed with a soy protein-free powdered semipurified diet and given orally for 3 mo. On d 90, the bone mineral density (BMD) in lumbar vertebrae, femur and its metaphyseal and diaphyseal zones (rich in cancellous and cortical bone, respectively) was lower in OVX than in SH (P < 0.01). In D or E(2), the four BMD were not different from SH, whereas in G, only the diaphyseal BMD was not different from SH. Image analysis performed in the distal femur metaphysis revealed that the cancellous bone area was lower in OVX than in SH (P < 0.01). Only the area in D was not different from that in SH. Finally, the bone turnover, which was higher in OVX than in SH (P < 0.005 and P < 0.05 for plasma osteocalcin concentration and urinary deoxypyridinoline excretion, respectively), was not different in G, D or E(2) compared with SH. Therefore, consumption of 17 alpha-ethinylestradiol or daidzein was more efficient than genistein in preventing ovariectomy-induced bone loss in rats.

Animals↗
PubMed2000

Dihydrotestosterone prevents glucocorticoid-negative effects on fetal rat metatarsal bone in vitro.

The effects of dihydrotestosterone (DHT) on glucocorticoid-pretreated fetal rat long bone were studied in an in vitro culture system. First, dose-response curves of corticosterone, hydrocortisone, and dexamethasone were studied at several concentrations. Then, hydrocortisone (H) at 10(-5) M was selected for the second part of the study, as it slackened rudiment mineralization (104 +/- 16% of the initial dark zone vs. 141 +/- 9% in control bones), as well as its lengthening (140 +/- 4% of the harvesting day length vs. 160 +/- 1% in control bones), by both inhibition of cell proliferation and stimulation of resorption. On the contrary, in H-pretreated metatarsal bones, DHT (10(-7) M) partly limited slackening of mineralization (124 +/- 5%) and lengthening (153 +/- 2%). Moreover, a control-like cell proliferation was re-established and resorption holes were filled in. Thus, in this study, DHT partly limited hydrocortisone-induced impairment of fetal rat metatarsal bone development.

Animals↗
PubMed2000

Amylin inhibits ovariectomy-induced bone loss in rats.

Amylin (AMY), a peptide co-secreted with insulin by pancreatic beta-cells, inhibits bone resorption and stimulates osteoblastic activity. The ovariectomized (OVX) rat is an established animal model for human osteoporosis. Thus, the present experiment was performed to study the effects of AMY on estrogen deficiency-induced bone loss in rats. Thirty-one 6-month-old Wistar rats were randomized by body weight (BW) into two groups. The first underwent surgical OVX (n=21). The second was sham-operated (SH; n=10). Sixty days after surgery, 11 OVX rats were s.c. injected with rat AMY (3 microg/100 g BW/day, for 30 days; OVX+AMY), and 10 with solvent alone in the same way (0.15 ml/100 g BW; OVX). Each rat, housed in an individual cage, was fed daily the mean quantity of diet consumed the day before by SH rats. This diet contained 0.24% calcium and 0. 16% phosphorus. The 31 animals were killed on day 90. No difference in daily weight gain and BW was observed between groups. Neither AMY treatment nor OVX had any significant effect upon femoral morphology, femoral failure load, diaphyseal femoral density (representative of cortical bone) and total femoral calcium content. Nevertheless, both distal metaphyseal (representative of cancellous bone) and total femoral bone densities were higher in SH and OVX+AMY than in OVX rats. The highest plasma osteocalcin concentration was measured in OVX+AMY rats. Simultaneously, urinary deoxypyridinoline excretion was lower in OVX+AMY than in OVX rats. These results indicate that in OVX rats, AMY treatment inhibited trabecular bone loss both by inhibiting resorption and by stimulating osteoblastic activity.

Amino Acids↗
PubMed1999

Endurance training and bone metabolism in middle-aged rats.

This study was performed to observe the influence of moderate treadmill running on bone of middle-aged male rats. Seventy 15-month-old Wistar rats were used. Ten initial controls (IC) were killed on day 0. Among the 60 others, three groups of ten exercised rats (E) run 1 h/day, 6 days/week at 60% of their maximum aerobic capacity. On days 30, 60 and 90 of the training period, 20 rats, ten E and ten R (resting animals), were killed. Femoral failure stress never varied and was never different in E and R during the experiment. On day 90 whole body mineral content and mineral density were higher in E than R. Simultaneously, total, diaphyseal and metaphyseal femoral densities were lower in R than IC or than in E. No difference was observed between IC and E. In resting rats, urinary deoxypyridinoline excretion (a marker of bone resorption) increased between days 0 and 90, while it did not change in runners. These results indicate that in middle-aged rats, moderate running prevents decrease in bone mineral density, probably by inhibiting bone resorption.

Aging↗
PubMed1999

Treadmill running starting 3 months after orchidectomy restores femoral bone mass in rats.

The present study was designed to provide data on the effects on femoral bone of endurance training starting only 3 months after orchidectomy in rats. A total of 70 Wistar male rats were used at 8 weeks of age. On day 0 of the experiment, 10 rats were killed by cervical dislocation to be used as first controls. Among the 60 other animals, half was surgically castrated (CX) or sham operated (SH). On day 90, 10 CX and 10 SH were killed and used as intermediary controls (ICX and ISH). Among the other 20 CX and 20 SH, 10 within each group (CXE, SHE) were selected for treadmill running (60% maximal oxygen uptake, 1 h x day(-1), 5 days x week(-1) for 12 weeks). The 20 other rats were used as sedentary controls (CXR, SHR) and killed (as runners) on day 180. On day 90 femoral bone density (BMD) and mineral content (BMC) were lower in ICX than in ISH. On day 180 total femoral BMD was lower in CXR than in CXE. Simultaneously metaphyseal femoral BMD was lower in CXR than in CXE, SHR or SHE. Furthermore, at that time, no significant difference concerning BMD and BMC was observed between SHR and CXE. This would indicate that treadmill running starting only 3 months after orchidectomy is able to restore BMD and BMC to control values, mainly by inhibiting bone resorption (as shown by decreased urinary deoxypyridinoline excretion in CXE) without decreasing osteoblastic activity (evaluated by plasma osteocalcin concentration).

Amino Acids↗
PubMed1999

Does endurance running before orchidectomy prevent osteopenia in rats?

This experiment was performed to study the effects on femoral bone of endurance training performed during the 3 months before orchidectomy in rats which were then killed 90 days later. A total of 70 male Wistar rats were used at 8 weeks old. One day 0 of the experiment, 10 rats were killed by cervical dislocation and used as first controls. Among the 60 others, 30 were selected for treadmill running (60% maximal oxygen uptake, 1 h x day(-1), 6 days x week(-1) for 90 days). The 30 other rats remained at rest. On day 90, 10 exercised (IE) and resting (IR) rats were killed and used as intermediary controls. Among the 20 other animals of each group, 10 were surgically castrated (CXE, CXR) or 10 sham-operated (SHE, SHR) and killed on day 180. On day 90 femoral failure load (three-point bending test) was greater in IE than in IR. Simultaneously, the deoxypyridinolinuria was lower in IE than in IR. On day 180, femoral bones were thinner in CXR than in CXE. The lowest values for trabecular bone are in the distal femoral metaphysis were measured in CXE and CXR rats, but the value measured in CXE was no different from that measured in SHR. Simultaneously total femoral bone density was lower in CXR than in SHE, while no difference concerning femoral metaphyseal density was observed between CXE and SHR. These results confirmed that endurance running increased femoral bone growth and modelling and femoral trabecular area, and thereby peak bone mass, in 8-month-old male rats. In resting animals, castrated after the training period, androgen deficiency decreased femoral density, mineral content and trabecular area. This decrease was not observed in castrated but previously exercised rats. Thus, by increasing peak bone mass, it was considered that endurance training may have a preventive effect against orchidectomy-induced bone loss.

Absorptiometry, Photon↗
PubMed1999

[Childhood croup].

Hoarseness, whooping cough and stridor are elements of a syndrome of upper airway obstruction. In childhood, acute laryngotracheobronchitis is by far the commonest cause of this syndrome. Yet, the differential diagnosis includes a number of rare and severe entities. In many cases, the traditional distinction between viral and spasmodic types is not possible. The value of humidifying therapy has not been established. In severe cases, nebulized adrenaline is of benefit but should be reserved for hospital. The effect lasts only two hours and at times a rebound effect is observed. It is now realized that some patients treated with adrenaline can safely be discharged after a two to three hours observation. There is a large body of evidence that all children arriving at the emergency department with croup should receive steroids without delay. This policy results in a much better outcome, with important reduction in hospitalizations, intensive care unit admissions and incubations. Oral dexamethasone is the drug of choice: it is as effective, easier to administer and cheaper than nebulised budesonide. In most studies, dexamethasone has been used at a dose of 0.6 mg/kg but there is some evidence that 0.15 mg/kg may be just as effective.

Child↗
PubMed1997

Influence of ovariectomy and estradiol treatment on calcium homeostasis during aging in rats.

Study was carried out an Wistar female rats to evaluate the consequences of ovariectomy and 17 beta-estradiol substitutive treatment during aging on bone. Ca metabolism and calciotropic hormones. Three groups of fifteen rats, mature, old and senescent (4-, 10-, and 28 month-old) female were fed a diet (6 g/100 g BW/day) containing 0.9% Ca and 0.8% Pi, Within each group, 10 rats were surgically ovariectomized (OVX). From day 1 until day 60 after OVX, they were subcutaneously injected with either 17 beta-estradiol (E: 10 micrograms/kg BW/48 h; n = 5) or with solvent alone (OVX; n = 5). Five other rats were sham operated (SH) and received solvent alone. Animals were put in balance 1 day per week to determine Ca and Pi intestinal apparent absorption and urinary pyridinium cross-links excretion was measured by HPLC. All rats were killed by exsanguination 60 days after OVX. Plasma was collected for measurement of intact parathyroid hormone (PTH), calcitonin (CT), insulin-like growth factor-1 (IGF-1), Ca and Pi. The success of OVX was confirmed at necropsy by observation of marked atrophy of the uterine horns. The right femur was collected, cleaned from adjacent tissue and used for mineral analysis. Despite correct matching for feeding, BW was significantly larger in 6 and 12 month-old OVX rats. OVX and 17 beta-estradiol had no significant effect upon plasma Ca, Pi and CT concentrations. Aging is associated with increased circulating PTH levels (pg/ml) (SH-6 months: 50.8 +/- 12.6; 12 months: 219.1 +/- 34.9; 30 months: 158.7 +/- 23.5; P < 0.05). Urinary and fecal Ca and Pi excretion in senescent animals were higher than in adult or old rats, thus resulting in a drastic fall in both intestinal apparent absorption and retention of Ca and Pi in 30 month-old animals. In each group, urinary pyridinium cross-links excretion and plasma osteocalcin concentration were higher in the OVX animals than in the controls, consistent with increased bone turnover in the estrogen deficient state. Both biochemical turnover markers were reduced in the estrogen-treated groups. In the same way, OVX increased and estrogen decreased the plasma IGF-1 levels. We conclude that 17 beta-estradiol prevents high turnover-induced osteopenia even in 30 month-old rats.

Aging↗
PubMed1997

Respiratory resistance by the forced oscillation technique in asthmatic children and cystic fibrosis patients.

Measurement of the total resistance of the respiratory system (Rrs) is an attractive alternative to measurement of forced expiratory volume in one second (FEV1) in young children because it requires minimal co-operation. The purpose of this study was to assess the ability of the forced oscillation technique (FOT) to detect airway obstruction in asthmatic children and in patients with cystic fibrosis (CF). Spirometry and Rrs were recorded in 45 asthmatic children (32 males and 13 females) and in 45 patients with CF (28 males and 17 females). Rrs was measured at 10 Hz with the Siregnost FD5 (Siemens, Germany). The asthmatic children were slightly younger than the patients with CF (10+/-3 vs 14+/-7 yrs), and had milder airway obstruction (FEV1 80+/-19 vs 66+/-27% of predicted). Rrs was significantly higher in the asthmatic children (6.6+/-1.7 cmH2O x L(-1) x s) than in the patients with CF (4.8+/-1.4 cmH2O x L(-1) x s). A normal FEV1 (> or = mean -2SD) was associated with a normal Rrs (< or = mean +2SD) in 17 of the 45 asthmatic children and in 13 of the 45 CF patients. By contrast, a low FEV1 (< mean -2SD) was associated with an increased Rrs (> mean +2SD) in 21 of the 45 asthmatic children, but in only 3 of the 45 CF patients. Thus, FEV1 and Rrs yielded concordant information in asthmatic children much more often (38 out of 45) than in CF patients (16 out of 45) (p < 0.001). In CF, Rrs failed to detect even severe airways obstruction. These findings might be accounted for by the inability of Rrs to reflect peripheral obstruction. We conclude that total respiratory resistance is suitable to assess airways obstruction in asthmatic children but not in cystic fibrosis patients.

Adolescent↗
PubMed1997

Influence of sex steroids on development of cultured fetal rat metatarsal bones.

The effects of 17 beta-estradiol (E), dihydrotestosterone (D, a non aromatisable androgen), and progesterone (P) on osteogenesis were studied on fetal rat cartilaginous anlagues cultivated in vitro. The three medial metatarsal rudiments were harvested at day 19 of gestation and grown in 1% BSA MEM medium (MO 643, Sigma) without serum nor antibiotics. After a 18h preincubation period, hormones were added for 8 days. Paired controls were incubated in the same volume of medium. The length, the metacarpal thickness and the size of the mineralized zone were measured every day, using a calibrated eyepiece (magnification X 40). DNA and protein synthesis, cartilage metabolism and mineralization were evaluated by monitoring the incorporation of 3H-Thymidine, 3H-Proline, 35S and 45Ca into anlagues for the last three hours of incubation, respectively. The dose/response effect of each steroid was studied at the concentrations of 10(-4) M, 10(-6) M, 10(-7) M and 10(-9) M. No difference was observed between male and female fetuses. A significant positive effect on total length (% of length measured at harvesting day) was observed with the 10(-7) M dose of E (163% +/- 2 vs 148% +/- 4 in controls) or D (158% +/- 3). Endochondral growth was not modified by P treatment. The effect of the three steroids (given at a dose of 10(-7) M) alone or as combinations (E, D, P, EP, ED, PD, EPD) confirmed the positive effect of E on endochondral growth and, to a lesser extend, of D and the association ED. Nevertheless, D had a better effect than E on endomembranous growth. On the contrary, P did not affect growth neither administrated alone nor in combination with E or D, while a positive effect of P on mineralization was demonstrated. The treatment associating the three steroids slowed down all the parameters concerning growth but strongly stimulated calcification.

Androgens↗
PubMed1996

Influence of ovariectomy on bone metabolism in very old rats.

Twenty-five 30-month-old Lou rats fed a diet (6 g/100 g BW/day) containing 0.9% Ca and 0.8% Pi were divided into five groups. Four groups were surgically ovariectomized. From day 2 until day 29 after ovariectomy, they were S.C. injected either with 17 beta estradiol (E2; 10 micrograms/kg BW/48 hours) or progesterone (P; 140 micrograms/kg BW/48 hours), or 17 beta estradiol + progesterone (E2P) at the same doses, or solvent alone (OVX). The fifth group was sham operated (SH) and injected with solvent. Urine was collected in metabolic cages from day 24 to 29 after ovx, and urinary pyridinoline (PYD) and deoxypyridinoline (DPD) excretion (markers of bone resorption) was measured by HPLC. All animals were killed 30 days after ovariectomy. Serum was then collected for measurement of osteocalcin (OC), alkaline phosphatase (ALP), parathyroid hormone (PTH), and calcitonin (CT). At necropsy, the success of ovariectomy was checked by marked atrophy of the uterine horns. Left and right femur were harvested for densitometric and mineral analysis, respectively. Ovariectomy had no significant effect upon plasma calcium and PTH concentrations. E2 or E2P treatment significantly increased plasma PTH and calcitonin concentrations. Plasma OC concentrations and ALP were not different in any of the groups. In contrast, urinary excretion of PYD and DPD was higher in OVX than in SH rats. Bone mineral density (BMD) of the distal femur was decreased by OVX, but was not different in the E2P and SH groups. A similar pattern was observed for the mineral or Ca content of whole femur. Thus, OVX decreased BMD and bone mineral content (BMC) in very old female rats. Plasma OC concentration and ALP activity failed to demonstrate any significant effect of OVX, whereas PYD and DPD were elevated. These results suggest that bone resorption is increased in OVX rats, even when supplemented with E2 or P alone. However, no significant difference was observed between SH and OVX rats treated with supplementation of both E2 and P. Thus, in very old rats, a combination of E2 and P is much more effective than E2 or P alone to prevent bone loss following ovariectomy.

Aging↗
PubMed1996

Tracheal distensibility in cystic fibrosis.

Size and distensibility of large airways have important implications for flow limitation and the efficacy of coughing. From radiological and functional data, some authors have suggested an increased size and distensibility of the trachea in cystic fibrosis (CF). Using computed tomography (CT) we compared size and distensibility of the trachea in 5 cystic fibrosis patients and five age- and height-matched healthy volunteers. Tracheal cross-sectional area was measured 25 mm below the cricoid cartilage. CT recordings were made at functional residual capacity, at 0 and +20 cmH2O mouth pressure. Inductive plethysmography was used to check that during these manoeuvres lung volume did not change and that the glottis remained open. Tracheal cross-sectional area and derived indices of tracheal distensibility were similar in the two groups. This study does not support the concept of an increased size and distensibility of the trachea in cystic fibrosis.

Adult↗
PubMed1995

EB 1089, a calcitriol analogue, decreases fetal calcium content when injected into pregnant rats.

EB 1089 is a calcitriol analogue with low calcaemic activity, which inhibits parathyroid hormone-related peptide (PTHrP) secretion in rats implanted with the Leydig cell tumour H-500. We have studied its effect on maternal and fetal plasma PTHrP concentrations and on fetal calcium and phosphorus contents in rats. Three groups of six pregnant rats were injected I.P. daily with EB 1089 (0.10, 0.25 and 0.50 microgram kg-1 in groups 1, 2 and 3, respectively, from day 12 to day 20 of gestation). The control group received an equal volume of solvent alone. On day 21 of gestation the animals were anaesthetized with chloral hydrate and blood samples were taken. Fetuses were collected, weighed and ashed for Ca and P measurements. PTHrP concentrations were measured by radioimmunoassay (RIA) in maternal and fetal plasma. Calcium content (mg (g fetal wt)-1; mean +/- S.E.M.) in control fetuses was not different from that measured in fetuses from dams given the lowest dose of EB 1089, but was higher than that in fetuses from rats injected with EB 1089 at 0.25 microgram kg-1 (1.18 +/- 0.20; P < 0.05) or 0.50 microgram kg-1 (1.08 +/- 0.29; P < 0.05). There was no difference in fetal P content between any of the groups of rats. The PTHrP concentration (pg equivalents human PTHrP(1-34) fragment ml-1) in maternal plasma from control rats (1.70 +/- 0.50) was not different from that in maternal plasma of rats given the lowest dose of EB 1089 (1.44 +/- 0.63).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

Effect of preinspiratory maneuver on the single-breath DLCO.

We have observed in some patients with pulmonary disease and normal subjects that the difference between two successive measurements for single-breath DLCO amounted to 10%. By scrutinizing data from these subjects, we observed that they spontaneously changed their preinspiratory maneuver just before inhaling the test gas mixture. The purpose of the present work is to assess the influence of five different preinspiratory maneuvers on DLCO. Nine healthy males were investigated. They performed at random the five following maneuvers: (A) rapid exhalation from functional residual capacity (FRC) to residual volume (RV), (B) rapid exhalation from FRC to RV and long apnea at RV, (C) rapid exhalation from FRC to RV and short apnea at RV, (D) slow exhalation at a constant speed from FRC to RV, and (E) curvilinear exhalation from FRC to RV. The DLCO values after maneuver B were higher than those after the four other maneuvers; there was a significant relationship between DLCO and the duration of the preinspiratory maneuver. The data are best explained by an alteration in the distribution of the inspired gas mixture to areas with different diffusing capacities. In conclusion, the preinspiratory maneuvers must be standardized in order to improve the reproducibility of the single-breath DLCO measurements.

Adult↗
PubMed1994

[The effect of a single dose of formoterol using an aerosol inhaler in asthmatic children. A randomized, controlled, double-blind study].

The duration of action of inhaled formoterol, a new long-acting beta-2-agonist, was compared to inhaled salbutamol and placebo in a double-blind, randomized, cross-over study in 16 children (8-12 years old) with stable moderate to serve asthma. Mean baseline FEV1 was 68 +/- 8% predicted. On the 4 study days, baseline FEV1 was within 15% of the FEV1 on visit 1. Two-three days apart, each patient inhaled either placebo, salbutamol (200 micrograms) formoterol (12 or 24 micrograms). FEV1 and PEF were measured repeatedly during 8 and 12 hours respectively. After formoterol, improvement over placebo remained significant at 8 hours for FEV1 (p = 0.006) and 12 hours for PEF (p = 0.01). When compared to salbutamol, it was significant at 8 hours for PEF (p = 0.03). There were no significant differences in lung function when comparing the 12 micrograms and 24 micrograms doses of formoterol. Side-effects were minimal.

Adrenergic beta-Agonists↗
PubMed1993

Spirometry in the asthmatic child: is FEF25-75 a more sensitive test than FEV1/FVC?

The use of spirometry in the assessment of children with asthma is taking on new importance with the realization that considerable airway obstruction may exist in the absence of clinically detectable abnormalities. There has been controversy over the value and relative sensitivity of various spirometry indices. This study evaluated the forced expiratory flow between 25% and 75% of vital capacity (FEF25-75), forced expired volume in 1 second (FEV1), and the ratio between the FEV1 and the forced vital capacity (FVC) in 100 asthmatic children aged 6-17 years, 29 of whom were wheezing at the time of the evaluation. All children with clinical wheezing had a FEV25-75 < 2 standard deviations (SD) below the mean (-2 SD), whereas 8 had a normal FEV1. The majority of the wheezing children had abnormalities of all 3 indices, whether expressed as < or = -2 SD or, in the case of the FEV1/FVC, arbitrarily taken as < 80%. Sixty-seven children of the entire study group had at least 1 abnormal spirometric index, but 38 of these had no clinical abnormalities. Twelve children had a reduced FEF25-75 as the only abnormality. These results suggest that FEF25-75 is a sensitive index of airway obstruction.

Adolescent↗