bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tracheal stenting improves airway mechanics in infants with tracheobronchomalacia
Authors: Zinman R. 
Published: March 2007

AbstractThe compliance and expiratory resistance of the tracheobronchial tree is increased in infants with tracheobronchomalacia because of a weakness in cartilaginous support of the airway. Life threatening episodes may occur in these patients due to airway collapse. The goals of this study were to compare the effects on respiratory system mechanics of stenting the airway with either continuous positive airway pressue (CPAP) or a long tracheostomy tube. Five infants were studied: two had bronchopulmonary dysplasia (BPD), 2 had associated congenital anomalies, and one had tracheomalacia and polydactyly; none had a tracheoesophageal fistula. All patients required tracheostomy and were treated with CPAP. Lung mechanics were evaluated by measuring transpulmonary pressure, obtained by subtracting airway opening pressure from pleural pressure measured with an esophageal balloon, and flow measured with a pneumotachometer placed in series with the tracheostomy. Dynamic compliance (Cdyn) and total respiratory system resistance (Rt) were calculated by two‐factor, least‐mean‐squares analysis, solving for the equation of motion of the lung with the PeDS® system (MAS, Hatfield). In all subjects Cdyn increased and R, decreased with increasing CPAP. In 4 subjects the airway was stented with a specially designed, long tracheostomy tube which reached to just above the carina; the special tube improved dynamic mechanics sufficiently to permit the discontinuation of CPAP. Speech was improved by fenestrating the tube and the use of a one‐way inspiratory valve, placed over the tracheostomy. Inspiration occurred via the tracheostomy and expiration was directed to the larynx. © 1995 Wiley‐Liss, Inc.
Dose‐response to inhaled nitric oxide in acute hypoxemic respiratory failure of newborn infants: A preliminary report
Authors: Bührer C. , Merker G. , Falke K. , Versmold H. , Obladen M. 
Published: March 2007

AbstractIn acute hypoxemic respiratory failure of term and near‐term neonates, extra‐ and intrapulmonary right‐to‐left shunting contribute to refractory hypoxemia. Inhaled nitric oxide (NO) decreases pulmonary arterial pressure and improves ventilation–hperfusion mismatch in a variety of animal models and selected human patients. We report on 10 consecutive term and near–term newborns with severe acute hypoxemic respiratory failure due to diaphragmatic hernia, meconium aspiration syndrome, group B streptococcus sepsis, pneumonia or acute respiratory distress syndrome, who received increasing doses of inhaled NO (up to 80 ppm) to improve the arterial partial pressure of oxygen (PaO2). The response to NO and the optimum NO concentration which improved PaO2 varied considerably between patients. Improvement of PaO2 was absent or poor (less than 10 mm Hg) in the 4 newborns with meconium aspiration syndrome and in 1 patient with congenital diaphragmatic hernia, while in the other 5 patients inhaled NO increased the mean (± SE) PaO2 from 41 ± 6 to 57 ± 9 mm Hg (P < 0.05). Optimum NO concentrations determined by dose‐response measurements performed during the first 8 hr of NO inhalation were 8–16 ppm except for 2 newborns with congenital diaphragmatic hernia who required 32 ppm to effectively increase PaO2. Four of the 5 patients in whom the PaO2 rose by more than 10 mm Hg received inhaled NO for extended periods of time (5 to 23 days) with no signs of tachyphylaxis. The optimum NO concentration dropped to less than 3 ppm after prolonged mechanical ventilation or when intravenous prostacyclin was given concomitantly. The response to inhaled NO and the optimum NO concentration to improve arterial oxygenation were virtually identical with conventional and high frequency oscillatory ventilation (HFO). We conclude that the optimal concentration of NO to improve PaO2 of neonates with acute hypoxemic respiratory failure varies considerably between patients, shows temporal variations, and requires individual and repeated adjustments of the concentration of inhaled NO. © 1995 Wiley‐Liss, Inc.
The single breath test in neonates: Does pressurization of the pneumotachograph make a difference?
Authors: Coates Allan L. , Fletcher Margaret E. , Dundas Isobel , Stocks Janet 
Published: March 2007

AbstractThe single breath test for the measurement of respiratory system resistance and compliance in newborns consists of an end inspiratory occlusion which is subsequently released, allowing expiration to proceed through a pneumotachograph (PNT). The measured flow is then integrated to give volume. The simplicity of the test is one of the major reasons for its popularity. However, some investigators have cautioned against the use of an occlusion distal to the PNT because pressurization of the PNT may introduce artifacts in the flow measurement. Despite this caution, many commercial systems use a pressurized PNT. This study investigated the errors that would result from pressurization of the PNT by providing a step function of flow to two infant PNTs, a Fleisch #0 and a Hans Rudolph 4500, in the unpressurized and pressurized state. In each case there was an initial rapid rise of the flow signal, followed by some overshoot and oscillations that rapidly died out. The overshoot and oscillations for the Hans Rudolph PNT were greater when pressurized whereas pressurization had little effect on the Fleisch PNT. Unpressurized, the two were similar. In either case, the artifact introduced by pressurization of the PNT died out so quickly that it would have little effect on any measurement in an infant. © 1995 Wiley‐Liss, Inc.
A cotton rat model of effectors of immunity to respiratory syncytial virus other than serum antibody
Authors: Piazza Franco M. , Schmidt H. Joel , Johnson Susan A. , Dotson Don L. , Darnell Miriam E. R. , Ottolini Martin G. , Porter David D. , Prince Gregory A. 
Published: March 2007

AbstractA model for studying effectors of immunity to respiratory syncytial virus (RSV) was developed. Pairs of inbred cotton rats (Sigmodon hispidus) were joined surgically using the technique of parabiosis. One week later, one animal of each pair was primed intranasally with small volume of RSV suspension. Fourteen days after priming, both animals of each pair were bled for determination of serum neutralizing antibody titers, and challenged intranasally with standard dose of RSV suspension. Single, unprimed cotton rats were challenged concomitantly and served as controls. Four days after challenge, all animals were sacrificed for virus titration of nasal tissues and lungs. Parabiosed cotton rats were surgically separated at varying intervals between priming and challenge (days 7, 9, 12, or 14 after priming) or were kept joined until sacrificed (day 18). Significant transfer of nasal and pulmonary immunity from primed to unprimed parabionts began 9 days after priming, gradually increasing through 18 days. Resistance to RSV challenge in spite of low levels of serum neutralizing antibody suggests that non‐antibody immunologic mediators were responsible for the transferred immunity. Evidence is presented for three broad categories of RSV immunologic effectors: systemic, local with transient systemic phase, and local without systemic phase. These categories are now amenable to further study using the described model. © 1995 Wiley‐Liss, Inc.
Characteristics of near‐fatal asthma in childhood
Authors: Martin A. J. , Campbell D. A. , Gluyas P. A. , Coates J. R. , Ruffin R. E. , Roder D. M. , Latimer K. M. , Luke C. G. , Frith P. A. , Yellowlees P. M. , McLennan G. 
Published: March 2007

AbstractAs part of the South Australian asthma mortality survey, we examined 30 cases of near‐fatal asthma attacks in children under 15 years of age who were seen over a 3‐year period from May 1988 to June 1991. Subjects presented with asthma and either respiratory arrest, PaCO2, above 50 mm Hg, and/or an altered state of consciousness or inability to speak on presentation at a metropolitan Adelaide teaching hospital. A standardized interview and questionnaire was completed with subjects/parents and medical practitioners. Data were reviewed by the assessment panel which made collective judgments based on predetermined criteria. Seventeen patients (57%) were male, 20% were less than 7 years of age, and the majority (53%) were aged between 12 and 15 years. The majority (83%) had severe asthma and only one case (3.3%) had mild asthma. Half of the subjects were waking every night due to asthma and 79% had significant exercise limitation. A quarter of the subjects had a previous ICU admission and 70% had a hospital admission in the last 12 months. Primary care was carried out by a general practitioner in 57% of cases, and 70% of subjects had a crisis plan. Only 46% of those older than 7 years of age had ever used a peak‐flow meter. Eighty percent of subjects or their families had high denial scores, and in 73% of cases psychosocial factors were considered to be significant. Eighty percent of cases experienced acute progressive respiratory distress, and 63% of cases delayed seeking medical care. The episode was judged as preventable in 83% of cases. This study suggests that most pediatric cases of near‐fatal asthma have severe asthma, significant denial, psychosocial pathology, and delay in seeking care, all of which contribute to the near‐fatal nature of these episodes. Pediatr Pulmonol, 1995; 20:1–;8 © 1995 Wiley‐Liss, Inc.
The effects of hyperoxia, mechanical ventilation, and dexamethasone on pulmonary antioxidant enzyme activity in the newborn piglet
Authors: Davis Jonathan M. , Robbins Carolyn G. , Anderson Tarek , Sahgal Namita , Genen Linda , Tierney Joan , Horowitz Stuart 
Published: March 2007

AbstractIt has been previously shown that prophylactic, intravenous dexamethasone (DEX) and intratracheal recombinant human Cu/Zn superoxide dismutase (SOD) ameliorate lung injury in newborn piglets treated with 48 hr of hyperoxia and mechanical ventilation. DEX has many pharmacologic effects, including the possible induction of antioxidant enzyme systems. To investigate whether the effects of DEX are mediated by an increase in endogenous antioxidant enzyme activity, 5 groups of term newborn piglets were studied: Group 1 piglets were ventilated with room air for 48 hr; Group 2 animals were ventilated with 100% O2, for 48 hr; Group 3 animals were ventilated with room air for 48 hr and received DEX (0.7 mg/kg) every 12 h; Group 4 were ventilated with 100% O2, for 48 hr and also received DEX; Group 5 animals were not ventilated and were sacrificed at time 0. At the conclusion of the studies, bronchoalveolar lavage (BAL) was performed and the lungs were removed and homogenized. Lung tissue and BAL were analyzed for SOD, catalase, GPX activities, and total protein concentration. No significant differences in any of these assays were seen in either lung tissue or BAL in the 5 groups. These observations indicate that 48 hr of hyperoxia, mechanical ventilation, or dexamethasone treatment does not induce activity of SOD, catalase, or glutathione peroxidase (GPX) in the lungs of newborn piglets. Thus postnatal DEX appears to minimize neonatal lung injury by mechanisms that are independent of these enzymes. Pediatr Pulmonol. 1995; 20:107–111. © 1995 Wiley‐Liss, Inc.
Bronchoalveolar lavage studies in children without parenchymal lung disease: Cellular constituents and protein levels
Authors: Midulla Fabio , Villani Alberto , Merolla Rocco , Bjermer Lief , Sandstrom Thomas , Ronchetti Roberto 
Published: March 2007

AbstractWe evaluated bronchoalveolar lavage fluid (BAL) for cellular constituents, concentration of total protein (TP), albumin (AL), fibronectin (FN), and hyaluronic acid (HA) in 16 children aged 2‐32 months without pulmonary inflammatory or parenchymal disease to establish reference values. We compared our data to those reported in older children and in normal adult volunteers. BAL results were obtained simultaneously from the right middle lobe and the lingula. Results indicated that children younger than 3 years of age had a higher number of cells/mL than older children and adults (59.9 × 104 vs. 17.6 × 104 and 12 × 104). Differential cell count revealed that the percentages of alveolar macrophages (AM), lymphocytes (LYM), and eosinophils (EOS) were similar to those obtained in older children and in adults, whereas the percentage of neutrophils (NEU) was higher in younger children (NEU 5.5 vs 1.6 and 1.2%, respectively) than in older children and adults. The latter difference was even greater in infants under 12 months of age (NEU 7.6%). The concentrations of TP, AL, FN, and HA in children's BAL samples were compared to values reported for adults. There were no differences between infants and children 13–32 months of age or normal adults. BAL fluid obtained simultaneously from the middle lobe and lingula were not significantly different. In conclusion, this is the first report on BAL values (cellular and noncellular constituents) in children younger than 3 years. The results may be used as reference values for further studies in children with parenchymal lung disease in this age group. Pediatr Pulmonol. 1995; 20:112–118. © 1995 Wiley‐Liss, Inc.
Glutathione metabolism in newborns: Evidence for glutathione deficiency in plasma, bronchoalveolar lavage fluid, and lymphocytes in prematures
Authors: Jain Ajey , Mehta Taral , Auld Peter A. M. , Rodrigues Jose , Ward Robert F. , Schwartz Morton K. , Mårtensson Johannes 
Published: March 2007

AbstractRespiratory distress in premature newborns is associated with deficiency of surfactant in the bronchoalveolar lining fluid; this may be influenced by a local deficiency of antioxidants. Severe L‐buthionine‐S, R‐sulfoximine‐induced depletion of glutathione (GSH, a major antioxidant) in rodents is associated with lung type 2 cell lamellar body damage and decreased concentrations in lung and bronchoalveolar lavage fluid (BALF) of phosphatidyl choline (a major component of surfactant). At birth, prematurely born newborns (30–34 weeks) had lower peripheral venous plasma GSH concentrations than term (>36 weeks) babies; these levels decreased further with increasing prematurity (>27 weeks, with respiratory distress). On day 2, the peripheral venous plasma GSH concentrations reached a nadir, and the lowest levels were found in the most premature newborns. Lymphocyte GSH concentrations were lowest on day 2 and day 7, and in prematures (< 27 weeks, with respiratory distress) remained below adult lymphocyte GSH levels for at least 4 weeks. At birth, prematures (<27 weeks, with respiratory distress) had a central plasma arterio‐venous (A‐V) GSH gradient across the lung (an estimate of lung uptake of GSH) of 0.72±0.15 (mean ± SD) μ‐mol/L; on day 2, the A‐V gradient did not change significantly (0.49 ± 0.09 μmol/L). At birth, these prematures had markedly decreased BALF GSH concentrations (compared with adult levels), and they were not significantly changed during the first 4 weeks of life. These results suggest that GSH deficiency is present in prematures and that it increases with the degree of prematurity. At birth, GSH deficiency will compromise the lungs' defense against oxidative stress injury. Oxidative stress is likely to increase if hyperoxic treatment is given for respiratory distress in these infants. Pediatr Pulmonol. 1995; 20:160–166. © 1995 Wiley‐Liss, Inc.
Prediction of maximum voluntary ventilation (MVV) in African‐American adolescent girls
Authors: Fulton Janet E. , Pivarnik James M. , Taylor Wendell C. , Snider Sharon A. , Tate Amanda L. , Frankowski Ralph F. 
Published: March 2007

AbstractThe purposes of the present study were to: (1) develop original equations to predict maximum voluntary ventilation (MVV) in African‐American adolescent girls; and (2) determine the validity of existing MVV prediction equations for use in African‐American subjects by comparing predicted MVV values in the literature with actual MVV values obtained in this study. Forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and 12 second MVV were measured with a clinical respirometer (Spirometrics model 2451) in 93 African‐American adolescent girls (13.5 ± 1.0 years). Age (r = 0.29). height (r = 0.38), FEV1 (r = 0.52), and FVC (r = 0.48) were significantly (P < 0.01) correlated with MVV. Multiple regression analysis was used to develop equations to predict MVV with age, height, and FEV1 as predictor variables. Using Mallow's Cp criterion, age‐FEV1 and FEV1, equations appeared to be the most accurate predictors of MVV. When MVV was regressed on FEV1, in a no‐intercept model, the result was the commonly cited equation MVV = 35.0 × FEV1. Thus, the previously established relationship between FEV1 and MVV can be extended to African‐American adolescent girls. Comparison of predicted MVV values calculated from other published equations with our subjects' actual values indicated that equations using age and/or height as predictors did not accurately predict MVV in our subjects. Pediatr Pulmonol. 1995; 20:225–233. © 1995 Wiley‐Liss, Inc.
Postnatal rat lung retinoic acid receptor (RAR) mRNA expression and effects of dexamethasone on RAR β mRNA
Authors: Grummer Mary A. , Zachman Richard D. 
Published: March 2007

AbstractRetinoids exert multiple effects upon lung differentiation and growth. Although the mechanisms involved are presently poorly understood, increasing evidence points to a central role of nuclear retinoic acid receptors (RAR). The purpose of this study was to determine RAR mRNA expression profile during postnatal alveolarization, compared with the expression in prenatal and adult rat lung, and to describe the effects of dexamethasone (DEX) and oxygen on postnatal lung RAR gene expression. Total RNA was isolated from lungs of Sprague‐Dawley rats on prenatal day 19, on postnatal days 1,3,7,10, and 14 of life, and from adults. One subgroup of littermate pups was treated with DEX daily for 3 or 7 days. In a second experiment, rats were exposed to room air or to 95% oxygen for 72 hours, and received either DEX or saline. Northern hybridization showed that the levels of all RAR subtypes in fetal lung were 45% or less of levels at postnatal day 1. The 3.7 kb RAR a transcript levels were lower than day 1 on days 10 and 14 (relative to day 1, day 10 = 0.54 ± 0.05; day 14 = 0.54 ± 0.08), but there was no change in a 2.7 kb RAR α transcript over this time period. By contrast, RAR βmRNA levels were significantly higher at days 3,10, and 14 compared with day 1 (day 3 = 1.79 ± 0.19; day 10 = 1.41 ± 0.14; day 14 = 1.53 ± 0.05). Similarly, RAR γ mRNA expresison levels were higher on day 10 (1.45 ± 0.09), but by day 14 there was no difference from day 1. Adult lung 3.7 kb RAR α, 2.7 kb RAR α, and RAR γ were lower than day 1, but RAR β was significantly greater (3.7 α = 0.52 ± 0.05; 2.7 α = 0.49 ± 0.26; γ = 0.74 2 ± 0.06; β = 1.63 ± 0.22). Treatment with DEX prevented the rise in RAR ß mRNA occurring on day 3 and significantly lowered (0.65 ± 0.06) the amount of RAR β mRNA in day 7 lung. Exposure of rat pups to oxygen caused an increase in RAR β mRNA (1.21 ± 0.03). DEX treatment again decreased RAR β mRNA in both control (0.55 ± 0.06) and oxygen‐exposed pups (0.67 ± 0.12). In addition, 2.7 kb RAR α mRNA was decreased with the combination of DEX and oxygen exposure (0.63 ± 0.06). The differential gene expression profiles and the response to DEX and oxygen of the various members of the RAR family suggest that each subtype may have a specific role during the period of alveolarization in rat lung. Pediatr Pulmonol. 1995; 20:234–240. © 1995 Wiley‐Liss, Inc.
Pulmonary vascular disorders masquerading as interstitial lung disease
Authors: Sondheimer Henry M. , Lung M. Colleen Lum , Brugman Susan M. , Iklé David N. , Fan Leland L. , White Carl W. 
Published: March 2007

AbstractDuring the acquisition of a series of 92 children with interstitial lung disease (ILD) over a 14 year period, a significant minority (8/92 or 9%) were initially diagnosed as having ILD, but were subsequently found to have a variety of arterial, venous, and/or capillary disorders that explained their initial pulmonary findings. This subgroup of patients has had a very high morbidity and mortality, with only three of eight patients currently surviving. The presentation, evaluation, and natural history of these eight children were reviewed. We developed a strategy of cardiac and pulmonary evaluation for children presenting with clinical and radiographic features of ILD that helped us to identify rapidly those with pulmonary vascular disorders. Pediatr Pulmonol. 1995; 20:284–288. © 1995 Wiley‐Liss, Inc.
Diagnosis of Mycoplasma pneumoniae pneumonia in pediatric patients by polymerase chain reaction (PCR)
Authors: Buck George E. , Eid Nemr S. 
Published: March 2007

AbstractPolymerase chain reaction (PCR) testing was performed on respiratory tract specimens obtained by throat swab in 21 children admitted to the hospital with suspected Mycoplasrna pneurnoniae pneumonia. Of 13 patients with a clinical condition compatible with mycoplasma infection and an immunological response to M. pneurnoniae, 11 were positive by PCR. Eight patients were negative by serology and/or had a clinical condition not compatible with mycoplasma infection, and all were negative by PCR. The antibody response to M. pneurnoniae was delayed for a week or more in 3 (23%) of the 13 patients with documented mycoplasma infection. These results suggest that PCR performed on a respiratory tract specimen obtained by a throat swab may be useful in the initial evaluation of children with suspected M. pneurnoniae pneumonia, especially in patients in whom the serological response is delayed. Pediatr Pulmonol. 1995; 20:297–300. © 1995 Wiley‐Liss, Inc.
Frequency and number of neuroendocrine tumor cells in prostate cancer: No difference between radical prostatectomy specimens from patients with and without neoadjuvant hormonal therapy
Authors: Shimizu Shinichiro , Kumagai Jiro , Eishi Yoshinobu , Uehara Toshitaka , Kawakami Satoru , Takizawa Touichiro , Koike Morio 
Published: March 2007

AbstractBACKGROUNDNeuroendocrine tumor cells in prostate cancer are thought to increase after hormonal therapy due to neuroendocrine differentiation of tumor cells. This assumption is based on the histological analyses of limited portions of the cancerous lesions examined.METHODSRadical prostatectomy specimens were obtained from 122 consecutive patients with prostate adenocarcinoma, 70 of whom underwent prostatectomy alone (Group A) and 52 with neoadjuvant hormonal therapy (Group B). Sections from all the 5‐mm‐thick slices from formalin‐fixed specimens were immunostained for chromogranin‐A, and the total number of choromogranin‐A‐positive neuroendocrine tumor cells were counted.RESULTSNo difference was found between Groups A and B in the frequency of cancer with neuroendocrine cells. The total number of neuroendocrine cells in cancer varied widely with no difference of median values in the two groups.CONCLUSIONSThese results do not support the assumption that hormonal therapy induces neuroendocrine differentiation, but suggest androgen‐independent neuroendocrine cells existed before therapy. Prostate 67: 645–652, 2007. © 2007 Wiley‐Liss, Inc.