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An antibiotic called fragarin showing activities against bacterial and fungal plant pathogens was isolated and purified by FPLC chromatography from the soluble fraction of strawberry leaves. The molecular weight value determined by mass spectrometry is 316 Da. Fragarin remains fully active after protease treatment or alkaline hydrolysis at 100 degrees C for 20 min. Biological and chemical analyses suggest that fragarin may be a new type of an antimicrobial preformed compound--phytoanticipin--and would constitute a primary non-specific barrier of strawberry defense.

The purpose of this study is to evaluate the effect of disodium cromoglycate (DSCG) on gas exchange and ventilation during incremental exercise in asthmatic children with an FEV1 fall less than 15 percent from the baseline after the exercise. Seventeen children (aged 8 to 14 years) with a history of mild to moderate asthma but no clinical and spirometric evidence of exercise-induced asthma (EIA) underwent two maximal exercise tests in a randomized order: test A without premidication and test B after inhalation of DSCG, 40 mg. To evaluate the effect of DSCG on normal airways, nine healthy children performed the same exercise protocol. Pulmonary function was normal at rest and after treadmill exercise test (the mean postexercise fall in FEV1 was 5.9 percent in test A and 1.5 percent in test B). Gas exchange, minute ventilation (VE) and heart rate (HR) were monitored during running in both tests. In the asthmatic subjects, there were no differences in oxygen uptake (VO2), carbon dioxide output (VCO2), and VE at rest between the two tests. During exercise, VE, VO2, VCO2, and energy cost (EC[O2 ml.kg-1.m-1]) of running in the asthmatic subjects were significantly lower in test B than in test A (analysis of variance, p < 0.01) for comparable work rates. Maximal minute ventilation (VEmax) was significantly higher in test A (46.9 +/- 14.6[+/- SD]L.min-1) than in test B (43.2 +/- 14 L. min-1; p < 0.05). We found no significant effect of DSCG on gas exchange and ventilation during exercise in the healthy children (VEmax 47.8 +/- 25 and 48.4 +/- 25 L.min-1 in test A and B, respectively). In conclusion, premedication with DSCG appears to decrease the ventilatory cost of exercise in asthmatic children who do not present a substantial fall in FEV1 after an exercise test without pretreatment.

In the last decade, the development of a number of ingenious techniques has led to the possibility of evaluating respiratory mechanics from the neonate up to children 3-4 yrs of age. Among these methods, the single-breath occlusion (SBO) technique and the multiple occlusion (MO) technique have gained extensive acceptance, and are used both in spontaneously breathing and mechanically-ventilated infants. These techniques allow the assessment of the passive mechanics of the total respiratory system (compliance, resistance and time constant), by evoking the Hering-Breuer inflation reflex, which results in relaxation of both inspiratory and expiratory muscles. These methods are suitable for repeated assessment in small infants and for longitudinal studies, because of their low invasivity, high reproducibility and relatively simple application. Pulmonary function tests may represent a useful guide in diagnosis, monitoring, prediction of outcome, and management assessment in infants and children with lung diseases. However all these techniques are limited by implicit assumptions and further developments towards simpler methods are needed.

In an attempt to investigate the relationship between respiratory mechanics and pulmonary hemodynamics, we evaluated pulmonary function in 31 infants with left-to-right shunts and subsequent high pulmonary blood flow, undergoing cardiac surgery. Measurements were performed 1 d before and repeated 10 d and 4-5 wk after correction. The age of the patients ranged from 4 d to 24 mo, body weight from 2.7 to 11.8 kg. Pulmonary artery pressure, assessed by Doppler echocardiography, was preoperatively elevated in 23 patients (group 1), whereas it was within normal values in eight infants (group 2). Respiratory mechanics were measured using the single-breath occlusion technique in sedated infants. To evaluate specific compliance, functional residual capacity was determined by using an open circuit nitrogen washout technique. A reduced preoperative compliance value (mean with 95% confidence interval) was found in group 1: 34.8 (26.5-43.1) mL.kPa-1. After hemodynamic correction, a progressive significant (p < 0.01) improvement was demonstrated at 10 d and 1 mo with values of 47.5 (39.2-55.8) mL.kPa-1 and 56.5 (45.6-67.4) mL.kPa-1, respectively. A similar trend was noted evaluating specific compliance with values of 0.27 (0.24-0.30) kPa-1 and 0.44 (0.42-0.46) kPa-1, respectively before and after surgery. Preoperative functional residual capacity value was 130 (100-160) mL. In group 2, normal preoperative compliance values were obtained, without significant changes after surgery. In both groups, resistance was within the normal range both before and after surgical correction, and functional residual capacity did not change either. No correlations were found between compliance and pulmonary artery pressure and pulmonary blood flow values.(ABSTRACT TRUNCATED AT 250 WORDS)

Respiratory mechanics were measured in 20 preterm infants before and in the 24-hr period after treatment with surfactant. All infants were enrolled in the rescue clinical trial with Curosurf carried out in the Neonatal Intensive Care Unit. They received a dose of 200 mg/kg lipid surfactant intratracheally after birth. Static compliance of the respiratory system (Crs) was measured by the single breath occlusion technique during both spontaneous and mechanical ventilation. Resistance of the respiratory system (Rrs) and expiratory time constant (Trs) were also measured. As early as 3 hr after surfactant administration a significant improvement of 45% in Crs measured during mechanical ventilation (CrsV) was noted (0.40 +/- 0.14 vs 0.58 +/- 0.17 mL/cm H2O/kg, P < 0.001), together with a significant improvement of the arterial/alveolar O2 tension ratio (Pa/AO2) (0.12 +/- 0.03 vs 0.30 +/- 0.16, P < 0.01). The improvement of CrsV and Pa/AO2 was confirmed 24 hr later (0.55 +/- 0.15 mL/cm H2O/kg and 0.33 +/- 0.18, respectively). A significant correlation was found between Crs and Pa/AO2 ratio (r = 0.56, P < 0.001). Time constant values were significantly higher after surfactant treatment (0.15 +/- 0.07 vs 0.09 +/- 0.03 sec; P < 0.01). Rrs remained unchanged. These data indicate that Curosurf given intratracheally after birth determines a rapid improvement of respiratory mechanics as soon as 3 hr after dosing, together with the improvement of oxygenation. From the findings obtained with the present study we show evidence that respiratory system mechanics may be a useful physiological measure to guide ventilatory strategy following surfactant therapy.

The purpose of this study was to evaluate the cardiorespiratory and metabolic response to exercise in 33 children, aged 9 to 15 years, affected by type I diabetes mellitus, in comparison with 47 age-, sex-, weight-, and height-matched healthy children. All diabetic children were on a mixed split-dose insulin regimen, consisting of both regular and long-acting insulin in the morning and evening. The last insulin injection was administered on average 6 hours before the test. The mean duration of diabetes mellitus was 5.0 +/- 3.1 years. The metabolic control was evaluated on the basis of HbA1 levels (mean, 8.9 +/- 1.8%). Pulmonary function tests and progressive exercise tests on the treadmill were performed. Gas exchange, ventilation, and heart rate (HR) were monitored during the tests. The O2 pulse (VO2/HR) was calculated. There was no difference in the baseline oxygen uptake (VO2) between the diabetic children and the control group. VO2 peak was significantly lower (P less than 0.01) in the diabetic adolescents (41.2 +/- 5.9 mL/min/kg) compared to control subjects (46.3 +/- 9.6 mL/min/kg) and it was achieved at an earlier (P less than 0.01) time of run (7.5 +/- 1.8 vs. 9.1 +/- 2.8 min). Anaerobic threshold and minute ventilation were similar in the two groups. The O2 pulse throughout the test was significantly lower (ANOVA, P less than 0.001) in the diabetic group compared to the controls. No differences were found in resting and post-exercise spirometric values. In conclusion, our study shows that well-controlled diabetic adolescents have a reduced working capacity.(ABSTRACT TRUNCATED AT 250 WORDS)

Spontaneous, positional, and paroxysmal positional nystagmus were studied before and after sectioning the superior division of the vestibular nerve and the anterior vestibular artery in squirrel monkeys. Histopathologic study of the temporal bones confirmed the degeneration of the macula utriculi with release of statoconia, but failed to identify the released utricular statoconia within the vestibular endolymphatic space in any animal. Postoperatively the animals consistently demonstrated direction-fixed spontaneous nystagmus until the end of the experiment (five months). Positional tests and Dix-Hallpike maneuver occasionally changed the intensity of the spontaneous nystagmus, but never elicited paroxysmal positional nystagmus. Possible reasons for not demonstrating paroxysmal positional nystagmus in the squirrel monkey are as follows: a resorption of statoconia; slight morphological alteration of the sensory epithelia of the posterior cristae; interference of the posterior crista function due to partial collapse of the membranous ampulla; the existence of interspecies difference; or possibly a faulty hypothesis regarding the etiologic mechanism of benign paroxysmal positional vertigo.

This is the first complete report on the histopathologic study of the temporal bones from an infant with a well-documented Pierre Robin syndrome (micrognathia, glossoptosis and cleft palate), demonstrating multiple middle and inner ear anomalies. The anomalies are basically architectural malformations rather than neutral or end organ developmental anomalies. The anomalies in this case, except for a few points, are somewhat similar in both ears. Multiple anomalies include: abnormal narrowing of the crus commune-utricle junction, superiorly located crus commune and posterior semicircular canal, underdeveloped modiolus, absence of the bony septum between the middle and apical coil (existence of scala communis in left ear), abnormally small internal auditory meatus, and abnormal direction of internal auditory canal, large cartilaginous mass around the superior semicircular canal and in the tympanic end of the fissula ante fenestram, small facial nerve, large facial bony canal dehiscence, anomalic stapes, etc.