bluuebunny/crossref_metadata_2025_split huggingface dataset:
Delivery of micronized budesonide suspension by metered dose inhaler and jet nebulizer into a neonatal ventilator circuit
Authors: Arnon S. , Grigg J. , Nikander K. , Silverman M. 
Published: March 2007

AbstractWe compared the delivery of a micronized suspension of budesonide by a metered dose inhaler (MDI) with two different spacers (Aerochamber and Aerovent) and by two jet nebulizers (MAD2 and Ultravent) to a ventilated neonatal test‐lung using a standard neonatal ventilator circuit. The combination of MDI and Aerochamber was significantly better at delivering budesonide to a filter in front of the test lung (14.2% of aerosolized dose) than were either the MDI and Aerovent (3.6%) or the Ultravent or MAD2 jet nebulizers (0.02% and 0.68% of initial reservoir dose). Of the droplets emerging from the MDI, Aerochamber, and ET tube, 18% of the initial dose was in droplets < 4.7 μm. Assuming that the test‐lung model accurately reflects in vivo deposition, the combination of MDI and Aerochamber appears to be an extremely effective way of delivering budesonide aerosol to ventilated newborn infants. © 1992 Wiley‐Liss, Inc.
Effect of rapid thoracic compression on the cerebral blood flow‐velocity patterns of small infants
Authors: Maynard Roy , Mammel Mark C. , Holloman Keith K. , Porter Sharon , Boros Stephen J. 
Published: March 2007

AbstractWe measured the middle cerebral artery (MCA) flow‐velocities of 12 small infants (mean weight, 2,882 ± 602 g) before, during, and after the rapid thoracic compression (RTC) maneuvers of partial forced expiratory flow‐volume studies. Cerebral flow‐velocities were measured using transcranial Doppler ultrasonography. RTC increased MCA end diastolic flow‐velocities and Pourcelot indices of all infants (P < 0.001). These values returned to baseline immediately after the release of chest compression. We also measured the MCA flow‐velocities of several preterm infants during their normal daily activities. The changes in flow‐velocity patterns observed during normal daily life were similar to those observed during RTC. These findings demonstrate that RTC produces real, but likely not pathologic, changes in cerebral blood flow‐velocities. © 1992 Wiley‐Liss, Inc.
Comparison of 2‐channel and 4‐channel pneumograms
Authors: Abdulhamid Ibrahim , Vauthy Pierre A. , Barnett Bruce A. , Hufford David R. , Reddy Ram P. , Hunt Carl E. 
Published: March 2007

AbstractTo determine whether the addition of air flow and O2 saturation (Sa) channels improves sensitivity of the pneumogram in identifying cardiorespiratory pattern abnormalities, 2‐and 4‐channel pneumograms (PG‐2 and PG‐4) were simultaneously recorded in 91 consecutive infants. Forty‐one infants (45%) had cardiorespiratory symptoms, and 50 were asymptomatic. Pneumograms were considered abnormal for any of the following: apnea ≧ 20 seconds, heart rate < 80 bpm for gt; 5 seconds in preterm and < 60 bpm in full‐term infants (bradycardia), shorter apnea with bradycardia or desaturation, periodic breathing gt; 7% of total sleep time in preterm and gt; 4% in full‐term infants, or Sa < 85% for gt; 5 seconds. Both recordings were normal in 72% of infants and abnormal in 24%. In only 4% were the PG‐4 abnormal when the PG‐2 were normal, in all instances due to minimum Sa levels of 77–84% for 5–19 seconds associated with central apnea of intermediate duration (three infants) or with mixed apnea. The difference in frequency of abnormal results between the PG‐2 and PG‐4 recordings was not statistically significant (X2). In conclusion, although PG‐4 do increase the scope of physiological information obtained in infants with cardiorespiratory events, this short‐term study does not establish whether this increase results in any long‐term benefits. Further, at least in this number and these types of at‐risk infants, PG‐4 do not improve the sensitivity of cardiorespiratory recordings for detecting abnormalities. © 1992 Wiley‐Liss, Inc.
Lung mechanics and gas exchange in ventilated preterm infants during treatment of hyaline membrane disease with multiple doses of artificial surfactant (Exosurf)
Authors: Pfenninger Jürg , Aebi Christoph , Bachrnann Denis , Wagner Bendicht Peter 
Published: March 2007

AbstractEight premature infants ventilated for hyaline membrane disease and enrolled in the OSIRIS surfactant trial were studied. Lung mechanics, gas exchange [Pa, arterial/alveolar P ratio (a/A ratio)], and ventilator settings were determined 20 minutes before and 20 minutes after the end of Exosurf instillation, and subsequently at 12‐24 hour intervals. Respiratory system compliance (Crs) and resistance (Rrs) were measured by means of the single breath occlusion method. After surfactant instillation there were no significant immediate changes in Pa (36 vs. 37 mmHg), a/A ratio (0.23 vs. 0.20), Crs (0.32 vs. 0.31 mL/cm H2O/kg), and Rrs (0.11 vs. 0.16 cm H2O/mL/s) (pooled data of 18 measurement pairs). During the clinical course, mean a/A ratio improved significantly each time from 0.17 (time 0) to 0.29 (time 12‐13 hours), to 0.39 (time 24‐36 hours) and to 0.60 (time 48‐61 hours), although mean airway pressure was reduced substantially. Mean Crs increased significantly from 0.28 mL/cm H2O/kg (time 0) to 0.38 (time 12‐13 hours), to 0.37 (time 24‐38 hours), and to 0.52 (time 48‐61 hours), whereas mean Rrs increased from 0.10 cm H,O/mL/s (time 0) to 0.11 (time 12‐13 hours), to 0.13 (time 24‐36 hours) and to (time 48‐61 hours) with no overall significance. A highly significant correlation was found between Crs and a/A ratio (r=0.698, P < 0.001). We conclude that Exosurf does not induce immediate changes in oxygenation as does the instillation of (modified) natural surfactant preparations. However, after 12 and 24 hours of treatment oxygenation and Crs improve significantly. In contrast to other reports on dynamic compliance and gas exchange, we have been able to demonstrate an excellent correlation between oxygenation and Crs, determined by the single breath occlusion method. © 1992 Wiley‐Liss, Inc.
A prospective trial using salivary‐theophylline levels to guide asthma therapy
Authors: Virchow Johann‐Christian , Mansfeld Jochen , Matthys Heinrich , Virchow Christian 
Published: March 2007

AbstractIn three prospectively designed studies, first saliva (SA) samples were collected simultaneously with serum (SE) from 86 children who received slow‐release theophylline (Th) bid. for treatment of bronchial asthma. SA was collected with a standardized sampling procedure. Regression analysis revealed a close correlation between SE and SA–Th levels (r=0.959; SE=1.87 × SA + 0.05) and yielded a “therapeutic SA–Th range” of 5.8 to 10.7 mg/L. In 16 children the diurnal variation was then assessed by measuring 6 SA–Th levels within 24 hr, using the same sampling method. At 0, 9, and 24 hr SE–Th levels were also measured. The levels of SE–Th and SA–Th were again closely correlated (0.914 ≤ r ≤ 0.949) and both remained constant over the 24‐hr period. In the third prospective trial only SA levels were used to monitor Th therapy in 50 asthmatic children. Seven days after starting therapy SA‐Th levels were measured and then the Th dose was increased weekly until SA‐Th levels above 5.8 mg/L were reached. The following day SE and SA samples were collected simultaneously and their Th levels compared. In 36 of the 47 children who completed the study therapeutic SE‐Th levels (≥10 and ≤20 mg/L) were measured; in one patient it was 320 mg/L, in 6 it was between 8.0 and 10 mg/L, and only 4 had SE levels <8.0 mg/L. There were no potentially toxic SE‐Th levels that were not reflected by increased SA levels. From these prospective studies we conclude that SA‐Th levels can be used to guide Th therapy in children with asthma. © 1992 Wiley‐Liss, Inc.
Chronic graft‐versus‐host disease and pulmonary function
Authors: Kaplan Ellen B. , Wodell Ruthven A. , Wilmott Robert W. , Leifer Betty , Lesser Martin L. , August Charles S. 
Published: March 2007

AbstractPulmonary complications are a major cause of morbidity and mortality in bone marrow transplant recipients. Earlier series, consisting mainly of adults, have shown evidence of obstructive changes of pulmonary functions in association with chronic graft‐versus‐host disease (CGVHD). We longitudinally evaluated spirometry in 46 patients who received bone marrow transplants as children or as young adults to determine whether they had similar abnormalities. Group mean FEV1/FVC, and percent predicted FVC, FEV1, and FEF25‐75 values did not demonstrate obstructive changes in association with CGVHD in this patient population. Our findings suggest that younger patients with CGVHD, as a group, may fare better than older bone marrow transplant recipients with CGVHD. However, due to small sample sizes, it cannot be conclusively stated that the pulmonary function parameters analyzed do not differ in the two patient groups. © 1992 Wiley‐Liss, Inc.
Facemasks versus mouthpieces for aerosol treatment of asthmatic children
Authors: Lowenthal Diana , Kattan Meyer 
Published: March 2007

AbstractMouthpieces and facemasks are being used with nebulizers for delivery of medication in acute asthma. To compare the effectivity of the two devices, 64 children age 6 to 19 years presenting to the hospital with acute asthma were enrolled in a randomized, single‐blind study. Group 1 used a facemask. Group 2 used a mouthpiece connected to the nebulizer via short T‐shaped tubing. Clinical evaluation and spirometry were performed at baseline and 20, 40, and 60 minutes after a single treatment with albuterol. Forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), and forced expiratory flow over the middle 50% of FVC (FEF25‐75) were determined at each point. Adverse effects were recorded. There was no significant difference in improvement between the groups. Patients with nasal congestion, age below 10 years, or severe airway obstruction did equally well with each method. Patients in the facemask group had a higher incidence of tremor. We conclude that the mouthpiece is an effective as the facemask and produces less tremor. © 1992 Wiley‐Liss, Inc.
Cilia in children with recurrent upper respiratory tract infections: Ultrastructural observations
Authors: Giorgi Pier Luigi , Oggiano Nicola , Braga Pier Carlo , Catassi Carlo , Gabrielli Orazio , Coppa Giovanni Valentino , Kantar Ahmad 
Published: March 2007

AbstractWe investigated the ultrastructure of nasal cilia in 27 children suffering from recurrent infections of the upper respiratory tract, during and after the onset of an acute respiratory infection, and after a convalescent period of 12 weeks. Our results demonstrated that in seven subjects after resolution of infection, the morphology of a large proportion of the cilia (32%) was not back to normal. These findings suggest a long‐term residual effect of infection, or the inability to reestablish normal ciliary structure during the convalescent period in some subjects with recurrent upper respiratory tract infection. © 1992 Wiley‐Liss, Inc.
Response to external obstruction in preterm infants with apnea
Authors: Upton C. J. , Milner A. D. , Stokes G. M. 
Published: March 2007

AbstractA proportion of preterm infants respond to an external airway obstruction by becoming apneic. We have studied 23 infants (median birthweight, 1.14 kg; gestation, 29 weeks) on 80 occasions, to determine the time course of the response and its relationship with spontaneous apnea occurrence. Upper airway flow was measured with a face mask and pneumotachograph, and a tap was turned intermittently to produce an occlusion.A total of 380 occlusions were analyzed. The infants became apneic during the obstruction on 72 occasions (19%), and after the obstruction on 122 occasions (32%). Both of these events were significantly more common than immediately prior lo the obstruction, when apnea occurred on 29 occasions (8%). Of the apneas following occlusion 57% were central in type. The point in the respiratory cycle at which obstruction occurred had no effect on the production of apnea. An obstruction score was calculated for each study. This was the mean of the number of apneas during and after each obstruction, expressed as a percentage of the number of obstructions per study. This score was positively correlated with the number of spontaneous apneas recorded. Obstruction score rose from a mean of 20% during days 0–14, to 34% during days 15–28, and thereafter it declined. This pattern may be relevant to the time course of apnea in susceptible infants. © 1992 Wiley‐Liss, Inc.
The relationship of RSV‐specific immunoglobulin E antibody responses in infancy, recurrent wheezing, and pulmonary function at age 7–8 years.
Authors: Welliver Robert C. , Duffy Linda 
Published: March 2007

AbstractIn order to determine if respiratory syncytial virus (RSV)‐specific IgE responses at the time of bronchiolitis in infancy are related to recurrent wheezing and pulmonary function at 7–8 years of age, a cohort of 43 infants was identified at the time of their initial RSV bronchiolitis episode. RSV‐specific IgE responses in nasopharyngeal secretions were determined, and patients were then followed prospectively with notation of the number of wheezing episodes and exposure to cigarette smoke at home. At 7–8 years of age the patients underwent skin testing to 7 environmental allergens and pulmonary function testing, including pulse oximetry and methacholine challenge. Pulmonary function following inhalation of bronchodilating agents was compared to baseline pulmonary function results in order to determine if abnormalities of pulmonary function were reversible. Recurrent wheezing following bronchiolitis was associated with the initial RSV‐IgE response, as well as with a family history of asthma. Current wheezing at age 7–8 years was associated with 2 or more positive skin tests (P < 0.01), a history of exercise‐induced wheezing (P = 0.01). and increased sensitivity to methacholine (P < 0.01). Pulmonary function test results were similar for groups with and without recurrent wheezing following bronchiolitis. For the entire study group, RSV‐IgE specific responses were unrelated to pulmonary function, but small airway dysfunction was associated with passive smoking (P < 0.025), and both large airway dysfunction and increased airway reactivity were associated with the number of positive skin tests (P < 0.025). Reduced small airway function improved following bronchodilator inhalation. The degree of improvement was inversely related to the degree of baseline dysfunction (P < 0.01), and was correlated with passive smoking (P < 0.01). These findings suggest that decreased pulmonary function following bronchiolitis is related to atopy and passive cigarette smoke exposure and may be reversible. © 1993 Wiley‐Liss, Inc.
Ontogeny of epithelial modulation of airway smooth muscle function in the guinea pig
Authors: Southgate W. Michael , Pichoff Bruce E. , Stevens Edward L. , Balaraman Venkataraman , Uyehara Catherine F. T. , Nakamura Kenneth T. 
Published: March 2007

AbstractThe purpose of this study was to investigate the ontogeny of guinea pig airway smooth muscle (ASM) responses and the epithelial modulation of these responses. Paired tracheal rings from fetal, newborn, and adult guinea pigs were studied. One of each pair was denuded of airway epithelium (AE) by gentle rubbing. Isometric tension was measured in rings mounted in organ baths filled with ‘Krebs’ solution. Cumulative dose‐response curves were generated by adding either acetylcholine (ACh) or histamine over a concentration range of 1 0−8−10−4 M. Significant agent‐specific, age‐related differences in maximal contraction were seen for both ACh and histamine in intact tissues (Ach: for fetus 66.7 ± 6.2 × 10−2 g/mg wet wt, for newborn 51.4 ± 6.2, for adult 29.3 ± 2.6; histamine: for fetus 46.1 ± 5.1, for newborn 72.9 ± 6.0, for adult 25.3 ± 3.2). Similar differences in sensitivity to both agents were observed (EC50 with ACh: for fetus 0.80 ± 0.11×10−6 M; for newborn 0.85 ± 0.26 × 10−6 M; for adult 1.7 ± 0.20 × 10−6M; EC50 with histamine: for fetus 1.88 ± 0.50 × 10−6 M; for newborn 1.34 ± 0.16 × 10−6M; for adult 3.78 ± 0.75 × 10−6 M). Removal of AE caused a significant decrease in maximal responses to ACh in fetal tissue, a smaller, insignificant one for newborn and a nonsignifcant alteration for adult tissues. Age‐related sensitivity difference was abolished with removal of AE to ACh but not to histamine. In conclusion, during development (1) maximum tension, expressed as force per tissue weight, when generated follows the pattern, fetus > newborn > adult with ACh and newborn > fetus > adult with histamine; (2) the EC50 pattern for both ACh and histamine was, fetus = newborn < adult; (3) for denuded tissue maximum tension by ACh was significantly decreased only in fetal trachea; and (4) removal of AE abolished the age‐dependent difference in sensitivity to ACh, but not to histamine. © 1993 Wiley‐Liss, Inc.
Nebulized steroid therapy in bronchopulmonary dysplasia
Authors: Cloutier Michelle M. , McLellan Nancy 
Published: March 2007

AbstractThe effect of inhaled beclomethasone dipropionate (BEC) was studied in seven infants between 7 and 18 months of age with glucocorticoid‐dependent bronchopulmonary dysplasia. Oral glucocorticoid therapy, pulmonary function, growth, daily caloric consumption, blood pressure, blood sugar, blood gases, and immunoglobulins were monitored for 3 months before (control period) and 3 months after (intervention period) instituting inhaled beclomethasone dipropionate (25 μg/kg/day divided tid) delivered by Pulmoaide with a DeVilbiss nebulizer. Acute BEC inhalation produced no change in pulmonary function. During BEC treatment, oral glucocorticoid therapy was decreased in all infants, stopped in four infants within 3 months and in the other three infants in 4‐5 months. Within 1 month of inhaled BEC the rate of linear growth and weight increased markedly (2.2 ± 1.8 vs 6.4 ± 2.4 cm/month ‐ mean ± SD and 9.3 ± 6.5 vs 18.2 ± 7.4 g/day, respectively without change in average daily caloric consumption (113 ± 16 vs. 110 ± 15 cal/kg/day). Immunoglobulins also significantly increased during BEC therapy (Ig G(Total) 246 ± 74 vs 463 ± 111 mg/dL). Pulmonary function revealed moderate obstructive pulmonary disease before BEC. After 3 months of BEC inhalation no significant change occurred although respiratory system resistance decreased and the flow at 25% of tidal volume to peak flow ratio increased more than predicted by intersession variability. In no infant did pulmonary function decline after BEC, nor were any apparent adverse effects noted in this small group of patients. In conclusion, inhaled BEC was effective in decreasing oral glucocorticoid therapy and in modifying glucocorticoid‐induced growth suppression in a very small, highly select group of infants with bronchopulmonary dysplasia. © 1993 Wiley‐Liss, Inc.
Episodes of spontaneous desaturations in infants with chronic lung disease at two different levels of oxygenation
Authors: McEvoy Cindy , Durand Manuel , Hewlett Valerie 
Published: March 2007

AbstractThe optimal range of pulse oximeter oxygen saturation (Sao2) for infants with chronic lung disease (CLD) has not been well established. We quantified episodes of spontaneous desaturation, at two different ranges of Sao2. For 1 hr each, we alternatively administered inspired O2 concentrations (Fio2, necessary to maintain an Sag of 94–96% or 87–91% to 21 patients (mean birth weight, 865 g; gestational age, 27.3 weeks; postnatal age 40.6 days) with CLD (defined by Fio2 > 0.21 at ≥ days and radiographic evidence). Sao2 was monitored with the Nellcor N‐200 oximeter and analyzed by a computer program (SatMaster). The percentage of time the infants desaturated to levels of Sao2 <85 and <80% revealed significantly fewer spontaneous episodes during the hour of higher baseline Sao2 (P < 0.0002). Comparison of episodes of spontaneous desaturation to Sao2 < 80 and <85%, lasting 0–15, 16–30, 31–45 sec also showed significant differences between the two levels of Sao2.We conclude that when Infants with CLD are maintained at a higher Sao2 they probably experience fewer episodes of spontaneous desaturations, because of less alveolar hypoxia. We bell that attempts at weaning the Fio2 should be tempered with the need of maintaining an adequate Sao2. Therefore, prolonged monitoring of oxygenation in infants with CLD at different levels of Sao2 could be helpful during the weaning process. Pediatr Pulmonol. © 1993 Wiley‐Liss, Inc.
A lamb model for human respiratory syncytial virus infection.
Authors: Lapin Craig D. , Hiatt Peter W. , Langston Claire , Mason Edward , Piedra Pedro T. 
Published: March 2007

AbstractRespiratory syncytial virus (RSV) is the most important cause of bronchiolitis and pneumonia in young children. The development of an animal model of RSV disease serves to better understanding the pathophysiology of airway disease from RSV infection in infants and children. Groups of six lambs were inoculated intratracheally (IT) or intranasally (IN) with a human strain of RSV (H‐RSV). For controls 8 lambs received IT virus‐free cell lysate. Tachypnea and fever were observed significantly more often following IT than following IN inoculation of H‐RSV or IT placebo (for tachypnea: 20 of 69 days, 5 of 63 days, and 3 of 89 days, respectively, P < 0.001; for fever: 6 of 69 days, 0 of 63 days, and 1 of 89 days, respectively, P < 0.02). Nasal fluid production was significantly more frequent in both IT (14 of 69 days) and IN (15 of 63 days) groups than in the placebo group (2 of 87 days, P < 0.001). Postvaccination geometric mean titers (GMT, arithmetic transformation of log 2) of RSV‐specific neutralizing antibody were significantly increased in the IT H‐RSV group compared with postplacebo GMTs at 1 week (72 vs. 6.7, P < 0.03). By the second week postinoculation both H‐RSV‐infected groups had comparable levels of RSV‐specific neutralizing antibody titers and had significantly greater GMTs for the second through to the fourth week than the placebo group (144, 128, and 4.8, respectively P < 0.0008). Bacterial isolates of the upper airway were comparable among the three groups. Histopathology at day 28 postinoculation was unremarkable for the three study groups. The development of overt clinical illness in lambs inoculated with H‐RSV suggests that the H‐RSV lamb model may be used to delineate the pathogenesis of lung injury of H‐RSV infection. © 1993 Wiley‐Liss, Inc.
Developmental control of collagen gene expression in the rat lung: Confirmation of early observations of lung growth
Authors: Larson Janet E. 
Published: March 2007

AbstractThe short gestation period of the rat allows one to see rapid morphologic and biochemical changes in the lung. It has been shown that the rat lung undergoes a period of distension over the first several days of life followed by a rapid alveolar growth. Total lung collagen also increases during this time period. We have examined the changes in types I and III procollagen transcrpts during the perinatal period and have compared them to the above observations. Total RNA was extracted from the lungs of offspring of time‐pregnant Sprague‐Dawley rats after large airways were removed. Northern hybridization was performed to determine the quality of steady‐state RNA and rule out cross‐hybridization while densitometric tracings of slot‐blot hybridizations allowed comparative estimates of the target sequence of RNA. Immediately following birth, the steady‐state rnRNA procollagen levels increased and a shift to a predominant type I production occurred. These changes preceded the rapid increase of collagen content and alveolarization known to occur at three days of age. These data provide further evidence that collagen production is controlled at the level of transcription and in temporal and tissue‐specific manners. © 1993 Wiley‐Liss, Inc.