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Dexamethasone, a glucocorticoid commonly used in pediatric patients, has potent anti-inflammatory and immunosuppressive properties. However, it is associated with side effects such as reduced lung function and decreased immunity. Pulmonary surfactant lipids are closely linked to lung disease and play a role in reducing surface tension, immune response and antiviral activity. The dysregulation of lipid metabolism is closely associated with lung disease. Hence, untargeted lipidomics may be instrumental in elucidating the effects of dexamethasone on pulmonary surfactant lipids. We obtained surfactant lipid samples from the bronchoalveolar lavage fluid of young mice injected subcutaneously with dexamethasone and conducted a comprehensive lipidomic analysis, comparing them with a control group. We observed a decrease in lipids, such as phosphatidylcholine, phosphatidylglycerol and phosphatidylethanolamine, and an increase in ceramide, fatty acid, diacylglycerol and monoglyceride, which may impact lung health. This study revealed the influence of dexamethasone on pulmonary surfactant lipids, offering new insights into adverse reactions in clinical settings., (© 2024 John Wiley & Sons Ltd.)

Pulmonary surfactant replacement therapy is a promising improvement in neonatal care for infants with respiratory distress syndrome. Lysophosphatidylcholine (LPC) is an undesirable component that can hinder surfactant proteins from enhancing the adsorption of surfactant lipids to balance surface tensions by creating a saturated coating on the interior of the lungs. A novel normal-phase liquid chromatography method utilizing UV detection and non-toxic solvents was developed and validated for the first time to analyze LPC in the complex matrix of pulmonary surfactant medication. The analytical method validation included evaluation of system suitability, repeatability, intermediate precision, linearity, accuracy, limit of detection (LOD), limit of quantification (LOQ), stability and robustness. The method yielded detection and quantification limits of 4.4 and 14.5 μg/ml, respectively. The calibration curve was modified linearly within the LOQ to 1.44 mg/ml range, with a determination coefficient of 0.9999 for standards and 0.9997 for sample solutions. Given the lack of reliable published data on LPC analysis in pulmonary surfactant medications, this newly developed method demonstrates promising results and offers advantages of HPLC methodology, including simplicity, accuracy, specificity, sensitivity and an exceptionally low LOD and LOQ. These attributes contribute to considering this achievement as an innovative method., (© 2024 John Wiley & Sons Ltd.)

Neonatal respiratory distress syndrome (nRDS) is a challenging condition to diagnose which can lead to delays in receiving appropriate treatment. Mid infrared (IR) spectroscopy is capable of measuring the concentrations of two diagnostic nRDS biomarkers, lecithin (L) and sphingomyelin (S) with the potential for point of care (POC) diagnosis and monitoring. The effects of varying other lipid species present in lung surfactant on the mid IR spectra used to train machine learning models are explored. This study presents a lung lipid model of five lipids present in lung surfactant and varies each in a systematic approach to evaluate the ability of machine learning models to predict the lipid concentrations, the L/S ratio and to quantify the uncertainty in the predictions using the jackknife + -after-bootstrap and variant bootstrap methods. We establish the L/S ratio can be determined with an uncertainty of approximately ±0.3 mol/mol and we further identify the 5 most prominent wavenumbers associated with each machine learning model., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Herein, an air-agitation liquid-liquid microextraction procedure was developed for the extraction of several polycyclic aromatic hydrocarbons from edible oil samples. In this study, the extraction procedure was achieved using a new magnetic deep eutectic solvent as the extraction solvent, in which there was no need for centrifugation. To enhance the rate of extraction of the analytes from the samples, the method was promoted by the use of surfactant addition. The extracted analytes were determined by high-performance liquid chromatography with a diode array detector. The influence of various parameters on the extraction efficiency was studied by response surface methodology using a central composite design. Under optimal conditions, linear calibration curves for the target analytes were achieved in the range of 0.43-250 ng g -1 . The limits of detection and quantification were in the ranges of 0.04-0.13 and 0.13-0.43 ng g -1 , respectively. The repeatability of the method in terms of intra- and inter-day precision was ≤4.7% and ≤6.7%, respectively. The extraction recovery of the method ranged from 75 to 88%. The obtained results show that the proposed method is efficient for the analysis of the target analytes in various oil samples without obvious matrix effects. Pyrene was found in olive oil at a concentration of 42 ng g -1 .

Stable isotope tracers, like 13 C, can be used for the measurement of the partition between the endogenous and exogenous pulmonary disaturated-phosphatidylcholine (DSPC). Deuterium labeling methods are still not fully explored. Our aim was to investigate the feasibility of using deuterium-depleted water (DDW) and deuterium-enriched water (DEW) to measure endogenous and exogenous pulmonary DSPC in a rabbit model of surfactant depletion. Data obtained from the 13 C dilution method were used as a reference. We studied 9 adult rabbits: 4 drank DDW and 5 DEW for 5 days. Lung surfactant depletion was induced at Day 5 by repeated saline bronchoalveolar lavages (BAL), which were stored as a pool (BAL pool). After endogenous surfactant depletion, rabbits received exogenous surfactant followed by a second BAL depletion procedure (End-Experiment Pool). DSPC quantity, and palmitic acid (PA)-DSPC 2 H/ 1 H (δ 2 H) and 13 C/ 12 C ratios (δ 13 C) of exogenous surfactant batches and of BAL pools were measured by High-Resolution Mass Spectrometry. The amount of exogenous surfactant recovered from the lungs ranged from 45% to 81% and, it was highly correlated with those obtained with the use of the 13 C (r = 0.9844, p < 0.0001). We demonstrated that commercially available purified DDW and even low doses of DEW can be used to modify the deuterium background of endogenous surfactants with the purpose of measuring the contribution of exogenous surfactants to the endogenous alveolar surfactant pool., (© 2022 Wiley Periodicals LLC.)

To provide novel data on surfactant levels in adult COVID-19 patients, we collected bronchoalveolar lavage fluid less than 72 h after intubation and used Fourier Transform Infrared Spectroscopy to measure levels of dipalmitoylphosphatidylcholine (DPPC). A total of eleven COVID-19 patients with moderate-to-severe ARDS (CARDS) and 15 healthy controls were included. CARDS patients had lower DPPC levels than healthy controls. Moreover, a principal component analysis was able to separate patient groups into distinguishable subgroups. Our findings indicate markedly impaired pulmonary surfactant levels in COVID-19 patients, justifying further studies and clinical trials of exogenous surfactant., (© 2022. The Author(s).)

Respiratory distress syndrome results from inadequate functional pulmonary surfactant and is a significant cause of mortality in preterm infants. Surfactant is essential for regulating alveolar interfacial surface tension, and its synthesis by Type II alveolar epithelial cells is stimulated by leptin produced by pulmonary lipofibroblasts upon activation by peroxisome proliferator-activated receptor γ (PPARγ). As it is unknown whether PPARγ stimulation or direct leptin administration can stimulate surfactant synthesis before birth, we examined the effect of continuous fetal administration of either the PPARγ agonist, rosiglitazone (RGZ; Study 1) or leptin (Study 2) on surfactant protein maturation in the late gestation fetal sheep lung. We measured mRNA expression of genes involved in surfactant maturation and showed that RGZ treatment reduced mRNA expression of LPCAT1 (surfactant phospholipid synthesis) and LAMP3 (marker for lamellar bodies), but did not alter mRNA expression of PPARγ, surfactant proteins (SFTP-A, -B, -C, and -D), PCYT1A (surfactant phospholipid synthesis), ABCA3 (phospholipid transportation), or the PPARγ target genes SPHK-1 and PAI-1. Leptin infusion significantly increased the expression of PPARγ and IGF2 and decreased the expression of SFTP-B. However, mRNA expression of the majority of genes involved in surfactant synthesis was not affected. These results suggest a potential decreased capacity for surfactant phospholipid and protein production in the fetal lung after RGZ and leptin administration, respectively. Therefore, targeting PPARγ may not be a feasible mechanistic approach to promote lung maturation.

Aspergillus fumigatus is an opportunistic fungal pathogen with small airborne spores (conidia) that may escape clearance by upper airways and directly impact the alveolar epithelium. Consequently, innate alveolar defense mechanisms are being activated, including professional phagocytosis by alveolar macrophages, recruitment of circulating neutrophils and probably enhanced secretion of pulmonary surfactant by the alveolar type II (AT II) cells. However, no data are available in support of the latter hypothesis. We therefore used a coculture model of GFP-Aspergillus conidia with primary rat AT II cells and studied fungal growth, cellular Ca2+ homeostasis, and pulmonary surfactant exocytosis by live cell video microscopy. We observed all stages of fungal development, including reversible attachment, binding and internalization of conidia as well as conidial swelling, formation of germ tubes and outgrowth of hyphae. In contrast to resting conidia, which did not provoke immediate cellular effects, metabolically active conidia, fungal cellular extracts (CE) and fungal culture filtrates (CF) prepared from swollen conidia caused a Ca2+-independent exocytosis. Ca2+ signals of greatly varying delays, durations and amplitudes were observed by applying CE or CF obtained from hyphae of A. fumigatus, suggesting compounds secreted by filamentous A. fumigatus that severely interfere with AT II cell Ca2+ homeostasis. The mechanisms underlying the stimulatory effects, with respect to exocytosis and Ca2+ signaling, are unclear and need to be identified., (© The Author(s) 2020. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology.)

Pulmonary surfactant main function is to reduce surface tension at alveolar interface. Two lipids phases coexist in surfactant membranes: a liquid-ordered (Lo) and a liquid-disordered (Ld) phases. This coexistence of phases would be crucial for the surfactant activity. Until now, the proportion of phases was determined qualitatively. We design an electronic spin resonance technique to quantify the lipid fraction in Ld phase. An exogenous pulmonary surfactant (EPS) with or without extra Cho was labeled with 5-doxil stearic acid to estimate the membrane fluidity and with TEMPO to determine the PL in Ld phase. A unique equation was established for the calculation of PL in Ld phase with an error of less than 3%. TEMPO partition coefficient was (0.78 ± 0.03). Cholesterol added to EPS did not modify this coefficient. The equation is valid for different batches of surfactant regardless of the cholesterol content. The proposed method is simple, precise and allows evaluating changes in lateral structure that could affect surfactant biophysical properties., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Calf pulmonary surfactant (CPS), which contains about 98% lipids and 2% hydrophobic surfactant proteins B (SP-B) and C (SP-C), has been used as a surfactant preparation for the clinical replacement therapy of respiratory distress syndrome (RDS). Characterization of SP-B and SP-C in CPS is informative for quality control and the evaluation of their biological activities. However, analysis of SP-B and SP-C is impeded by the high content of lipids in CPS. Here, we describe an integrated method by combining size exclusion chromatography (SEC)-based delipidation, SDS-PAGE separation, in-gel digestion and mass spectrometric analysis for comprehensive characterization and proteoform analysis of the extremely hydrophobic SP-B and SP-C in CPS. This study has shown that 30 proteoforms of SP-C with different truncations and modifications were identified and SP-B was found to be existed as a dimer form in the CPS., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The article reveals the modern aspects of IPF pathogenesis in with an emphasis on the main proposed prognostic biomarkers. IPF remains the leader among diseases with unknown etiology, the diagnosis and management of which are not very successful, despite the obvious progress in molecular medicine. There is presented analysis of the significance of IPF potential biomarkers and their concentrations in the blood and bronchoalveolar lavage fluids (BAL): endothelin-1, CC-chemokine ligand 18, interleukin-1, surfactant protein SP-D in the review. The role of their changing levels in the blood and BAL for assessing the course of the IPF and its prognosis, as well as the prevailing importance of the polymorphism of the genes encoding them, is shown. Obviously, the progressive accumulation of fibroblast-myofibroblast cells in the lungs IPF patients worsens the prognosis of disease, forms its own environment with a set of cytokines, growth factors, collagen, fibronectin in the extracellular matrix of fibrous lungs. The insufficient amount of studies in the face of the rarity of the disease leaves a lot of controversial issues for solution in the future. Obviously, to assess the prognosis of IPF mortality, it is necessary to include a very large number of patients, to extend the observation period, which increases their cost and reduces the opportunities and desire of pharmaceutical companies to participate in these studies.

Background: The amount of surfactant deposited in the lungs and its overall pulmonary distribution determine the therapeutic outcome of surfactant replacement therapy. Most of the currently available methods to determine the intrapulmonary distribution of surfactant are time-consuming and require surfactant labelling. Our aim was to assess the potential of Mass Spectrometry Imaging (MSI) as a label-free technique to qualitatively and quantitatively evaluate the distribution of surfactant to the premature lamb., Methods: Twelve preterm lambs (gestational age 126-127d, term ~150d) were allocated in two experimental groups. Seven lambs were treated with an intratracheal bolus of the synthetic surfactant CHF5633 (200 mg/kg) and 5 lambs were managed with mechanical ventilation for 120 min, as controls. The right lung lobes of all lambs were gradually frozen while inflated to 20 cmH 2 O pressure for lung cryo-sections for MSI analysis. The intensity signals of SP-C analog and SP-B analog, the two synthetic peptides contained in the CHF5633 surfactant, were used to locate, map and quantify the intrapulmonary exogenous surfactant., Results: Surfactant treatment was associated with a significant improvement of the mean arterial oxygenation and lung compliance (p < 0.05). Nevertheless, the physiological response to surfactant treatment was not uniform across all animals. SP-C analog and SP-B analog were successfully imaged and quantified by means of MSI in the peripheral lungs of all surfactant-treated animals. The intensity of the signal was remarkably low in untreated lambs, corresponding to background noise. The signal intensity of SP-B analog in each surfactant-treated animal, which represents the surfactant distributed to the peripheral right lung, correlated well with the physiologic response as assessed by the area under the curves of the individual arterial partial oxygen pressure and dynamic lung compliance curves of the lambs., Conclusions: Applying MSI, we were able to detect, locate and quantify the amount of exogenous surfactant distributed to the lower right lung of surfactant-treated lambs. The distribution pattern of SP-B analog correlated well with the pulmonary physiological outcomes of the animals. MSI is a valuable label-free technique which is able to simultaneously evaluate qualitative and quantitative drug distribution in the lung.

Objective: The stable microbubble test on gastric aspirate and on amniotic fluid has been used for the diagnosis of respiratory distress syndrome in the newborn. However, no study has performed this test on oral aspirates from premature infants. The objective of this study was to evaluate the performance of the stable microbubble test on oral aspirates from preterm newborns to predict respiratory distress syndrome., Method: This study included infants with gestational age <34 weeks. Oral fluids were obtained immediately after birth and gastric fluids were collected within the first 30 minutes of life. The samples were frozen and tested within 72 hours., Results: The sample was composed of paired aspirates from 64 newborns, who were divided into two groups: respiratory distress syndrome group (n=21) and control group (n=43). The median (interquartile range) of the stable microbubble count in the oral samples of infants with respiratory distress syndrome was significantly lower than that of infants who did not develop respiratory symptoms: respiratory distress syndrome group=12 (8-22) stable microbubbles/mm 2 ; control group=100 (48-230)microbubbles/mm 2 (p<0.001). The correlation between microbubble count in gastric and oral aspirates was 0.90 (95% confidence interval=0.85-0.95; p<0.001). Considering a cut-off point of 25microbubbles/mm 2 , the sensitivity and the specificity of the stable microbubble test were 81.4% and 85.7%, respectively., Conclusion: The study suggests that the stable microbubble test performed on oral aspirate is a reliable alternative to that performed on gastric fluid for the prediction of respiratory distress syndrome in the newborn., (Copyright © 2018 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.)

Background: It is not known if the endogenous surfactant pool available early in life is associated with the RDS clinical course in preterm neonates treated with CPAP. We aim to clarify the clinical factors affecting surfactant pool in preterm neonates and study its association with CPAP failure., Methods: Prospective, pragmatic, blind, cohort study. Gastric aspirates were obtained (within the first 6 h of life and before the first feeding) from 125 preterm neonates with RDS. Surfactant pool was measured by postnatal automated lamellar body count based on impedancemetry, without any pre-analytical treatment. A formal respiratory care protocol based on European guidelines was applied. Clinical data and perinatal risk factors influencing RDS severity or lamellar body count were real-time recorded. Investigators performing lamellar body count were blind to the clinical data and LBC was not used in clinical practice., Results: Multivariate analysis showed gestational age to be the only factor significantly associated with lamellar body count (standardized β:0.233;p = 0.023). Lamellar body count was significantly higher in neonates with CPAP success (43.500 [23.750-93.750]bodies/μL), than in those failing CPAP (20.500 [12.250-49.750] bodies/μL;p = 0.0003).LBC had a moderate reliability to detect CPAP failure (AUC: 0.703 (0.615-0.781);p < 0.0001; best cut-off: ≤30,000 bodies/μL). Upon adjustment for possible confounders, neither lamellar body count, nor its interaction factor with gestational age resulted associated with CPAP failure., Conclusions: Early postnatal lamellar body count on gastric aspirates in CPAP-treated preterm neonates with RDS is significantly influenced only by gestational age. Lamellar bodies are not associated with CPAP failure. Thus, the endogenous surfactant pool available early in life only has a moderate reliability to predict CPAP failure.

Inhalation of commonly present irritants, such as chlorine and chlorine derivatives, can cause adverse respiratory effects, including irritant-induced asthma (IIA). We hypothesize that due to airway barrier impairment, exposure to hypochlorite (ClO - ) can result in airway hypersensitivity. C57Bl/6 mice received an intra-peritoneal (i.p.) injection of the airway damaging agent naphthalene (NA, 200 mg/kg body weight) or vehicle (mineral oil, MO). In vivo micro-computed tomography (CT) images of the lungs were acquired before and at regular time points after the i.p., Treatment: After a recovery period of 14 days an intranasal (i.n.) challenge with 0.003% active chlorine (in ClO - ) or vehicle (distilled water, H 2 O) was given, followed by assessment of the breathing frequency. One day later, pulmonary function, along with pulmonary inflammation was determined. Lung permeability was assessed by means of total broncho-alveolar lavage (BAL) protein content and plasma surfactant protein (SP)-D levels. In vivo micro-CT imaging revealed enlargement of the lungs and airways early after NA treatment, with a return to normal at day 14. When challenged i.n. with ClO - , NA-pretreated mice immediately responded with a sensory irritant response. Twenty-four hours later, NA/ClO - mice showed airway hyperreactivity (AHR), accompanied by a neutrophilic and eosinophilic inflammation. NA administration followed by ClO - induced airway barrier impairment, as shown by increased BAL protein and plasma SP-D concentrations; histology revealed epithelial denudation. These data prove that NA-induced lung impairment renders the lungs of mice more sensitive to an airway challenge with ClO - , confirming the hypothesis that incomplete barrier repair, followed by irritant exposure results in airway hypersensitivity.

Purpose: To quantify and compare the amounts of surfactant proteins SP-A, SP-B, SP-C and SP-D in the tear fluid collected from patients with dry eye syndrome and from individuals with a healthy ocular surface., Methods: Schirmer strips were used to collect tear fluid from both eyes of 241 volunteers (99 men, 142 women; age range: 18-87 years). Dry eye syndrome was diagnosed by ophthalmologists in 125 patients, whereas the healthy control group comprised 116 individuals. The total protein concentration was determined via Bradford assay. The relative concentration of surfactant proteins SP-A through -D was measured by enzyme-linked immuno-sorbent assay (ELISA)., Results: The mean relative concentrations of SP-A, SP-C and SP-D were significantly higher in the dry eye group as compared to the healthy controls (p<0.05, one-way ANOVA). SP-B was also detected at a higher concentration in the dry eye group, but the difference to the control group was not statistically significant., Conclusions: The upregulation of SP-A and SP-D in the dry eye group is probably related to these proteins' known antimicrobial and immunomodulatory effects at the ocular surface. It may represent a pathophysiological response to the inflammatory condition of the ocular surface in dry eye. The upregulation of SP-B and SP-C may represent an effort of the lacrimal system to reduce surface tension and thus to counteract the increased tendency of the tear film to tear in dry eye., (Copyright © 2017 Elsevier GmbH. All rights reserved.)

Objectives: Acute respiratory distress syndrome (ARDS) is caused by many factors including inhalation of toxicants, acute barotrauma, acid aspiration, and burns. Surfactant function is impaired in ARDS and acute airway injury resulting in high surface tension with alveolar and small airway collapse, edema, hypoxemia, and death. In this study, we explore the mechanisms whereby surfactant becomes dysfunctional in ARDS and bronchiolitis and its repair with a cyclodextrin drug that sequesters cholesterol., Methods: We used in vitro model systems, a mouse model of ARDS, and samples from patients with acute bronchiolitis. Surface tension was measured by captive bubble surfactometry., Results: Patient samples showed severe surfactant inhibition even in the absence of elevated cholesterol levels. Surfactant was also impaired in ARDS mice where the cholesterol to phospholipid ratio (W/W%) was increased. Methyl-β-cyclodextrin (MβCD) restored surfactant function to normal in both human and animal samples. Model studies showed that the inhibition of surfactant was due to both elevated cholesterol and an interaction between cholesterol and oxidized phospholipids. MβCD was also shown to have anti-inflammatory effects., Conclusions: Inhaled cyclodextrins have potential for the treatment of ARDS. They could be delivered in a portable device carried in combat and used following exposure to toxic gases and fumes or shock secondary to hemorrhage and burns.

Exhaled particles constitute a micro-sample of respiratory tract lining fluid. Inhalations from low lung volumes generate particles in small airways by the airway re-opening mechanism. Forced exhalations are assumed to generate particles in central airways by mechanisms associated with high air velocities. To increase knowledge on how and where particles are formed, different breathing manoeuvres were compared in 11 healthy volunteers. Particles in the 0.41-4.55μm diameter range were characterised and sampled. The surfactant lipid dipalmitoylphosphatidylcholine (DPPC) was quantified by mass spectrometry. The mass of exhaled particles increased by 150% (95% CI 10-470) for the forced exhalation and by 470% (95% CI 150-1190) for the airway re-opening manoeuvre, compared to slow exhalations. DPPC weight percent concentration (wt%) in particles was 2.8wt% (95%CI 1.4-4.2) and 9.4wt% (95%CI 8.0-10.8) for the forced and the airway re-opening manoeuvres, respectively. In conclusion, forced exhalation and airway re-opening manoeuvres generate particles from different airway regions having different DPPC concentration., (Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.)

Respiratory distress is a major cause of mortality in cloned neonatal animals, but its pathogenesis remains poorly understood. Here, we used necropsy and histology procedures to evaluate the lungs of cloned neonatal bovines dying of respiratory distress, finding incomplete lung dilation, alveolar collapse, and thickened alveolar walls. Comparison of the transcriptomes between collapsed lungs of cloned bovines and their normal counterparts revealed 1373 differentially expressed genes in collapsed lungs (p < 0.05, fold change >1.5 or <1.5 -1 ), many of which were associated with surfactant biosynthesis, secretion, transport, recycling, and degradation. ERK/MAPK and Notch signaling pathways were among the canonical pathways relevant to surfactant homeostasis. Expression of the genes encoding Surfactant protein B (SPB) and Surfactant protein C (SPC)-which control surfactant lipid packing, spreading, and stability-were significantly lower in collapsed lungs of cloned neonates at the transcript (p < 0.01) and protein levels (p < 0.05) relative to that in normal lungs. Thus, our results provide an initial view into the changes in gene expression in cloned newborns with lung collapse and respiratory distress, and present a valuable resource for developing novel preventive or therapeutic strategies to reduce the mortality rate of cloned animals and to improve the efficiency of somatic cell nuclear transfer technology., (© 2017 Wiley Periodicals, Inc.)

Objective To explore the effect of hyperoxia on the expressions of CCAAT enhancer binding protein α (C/EBPα) and pulmonary surfactant proteins (SP-A, SP-B, SP-C, SP-D) and their correlations in primary type II alveolar epithelial cells (AECIIs) from premature rats. Methods AECIIs were divided into an air control group and a hyperoxia model group. The cells of the two groups were respectively exposed toair and 950 mL/L O 2 . The cells were harvested at 24, 48, and 72 hours after exposure. Inverted phase-contrast microscope was used to observe morphological changes of the cells. Real-time quantitative PCR and Western blotting were performed to measure the mRNA and protein expressions of C/EBPα, SP-A, SP-B, SP-C and SP-D. Cell Counting Kit-8 (CCK-8) was applied to detect the proliferation of AECIIs. Results With the prolonging incubation time, the air group showed a significantly decreasing mRNA and protein expressions of C/EBPα, and significantly ascending mRNAand protein expressions of SP-A, SP-B, SP-C, SP-D and increasing proliferation of AECIIs. The mRNA and protein expressions of SP-A, SP-B, SP-C, SP-D and the proliferation of AECIIs in the hyperoxia group showed a trend of increasing at first and then decreasing as the culture time went on. Compared with the air group, the hyperoxia group showed significantly increased mRNA and protein expressions of C/EBPα and SP-A, SP-B, SP-C, SP-D and enhanced proliferation of AECIIs at 48 hours. In the hyperoxia group, the protein expression of C/EBPα was positively correlated with the protein expressions of SP-A, SP-B, SP-C, SP-D as well as the proliferation of AECIIs(r=0.96, 0.98, 0.92, 0.97, 0.90). Conclusion In the early stage of hyperoxia exposure, C/EBPα can promote the secretion of pulmonary surfactant protein to participate in the body's protective regulation. However, over the time of hyperoxia exposure, C/EBPα loses compensatory protective effect.

Introduction: Previous studies have suggested that full-term newborns delivered by elective cesarean section who develop transient tachypnea have low gastric microbubble counts. In the present study, microbubble concentrations in oral fluid samples were used to evaluate pulmonary maturity., Objective: To evaluate lung maturity in full-term newborns delivered by elective caesarean section using the stable microbubble test in oral aspirates collected at birth., Method: The study involved newborns with gestational age >37 weeks delivered by elective cesarean section. Oral fluid samples were obtained in the delivery room immediately after birth, and gastric fluid was collected within the first hour of life. Samples were frozen and analyzed by two blinded researchers., Results: The sample comprised 544 newborns. Twenty-two were diagnosed with transient tachypnea of the newborn by the assisting physician, and required admission to the Neonatal Intensive or Intermediate Care Unit. The median (interquartile range) of the number of microbubbles in the oral samples of these patients was 67.5 (45-150) microbubbles/mm(2) . The remaining 498 newborns without respiratory difficulties had a count of 350 (150-750) microbubbles/mm(2) -P < 0.001. Gastric fluid tests revealed a count of 150 (82.5-700) microbubbles/mm(2) for neonates with respiratory difficulties, and of 600 (216-1125) microbubbles/mm(2) -P < 0.05 for those without respiratory symptoms., Conclusion: The present results suggest that transient tachypnea of the newborn is associated with surfactant dysfunction. Pediatr Pulmonol. 2016;51:596-600. © 2015 Wiley Periodicals, Inc., (© 2015 Wiley Periodicals, Inc.)

Pulmonary surfactant (PS) is characterized by a highly conserved lipid composition and the formation of unique multilamellar structures within the lung. An unusually high concentration of DPPC is a hallmark of PS and is critical to the formation of a high surface area, stable air/water interface; the unusual lipid polymorphisms observed in PS are dependent on surfactant proteins, particularly lung surfactant protein B (SP-B). The molecular mechanisms of lipid trafficking and assembly in PS remain largely uncharacterized. Using (2)H and (31)P NMR, we characterize the dynamics and polymorphisms of the major lipid species in native PS and synthetic lipid mixtures as a function of SP-B1-25 addition. Our findings point to increased dynamics and a departure from a lamellar behavior for DPPC on addition of the peptide, consistent with our observations of DPPC phase separation in native surfactant. The monounsaturated lipids POPC, POPG and POPE remain in a lamellar phase and are less affected than DPPC by surfactant peptide addition. Additionally, we demonstrate that the properties of a native PS can be successfully mimicked by using a fully synthetic lipid mixture allowing the efficient evaluation of peptidomimetics under development for PS replacement therapies via NMR spectroscopy. The specificity of the dynamic changes in DPPC relative to POPC suggests the importance of tuning partitioning properties in successful peptidomimetic design., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Aims: To investigate the histopathological manifestations of two fatal cases of H7N9 influenza A virus infection., Methods: Pulmonary and hepatic specimens from two fatal cases of H7N9 influenza virus infection were examined using H&E staining. Additionally, in situ hybridisation was performed with probes (ViewRNA) targeting H7N9 RNA and IP-10, interleukin (IL)-6 mRNA. The distribution of surfactant protein A (SP-A), surfactant protein B (SP-B), CD3, CD4, CD8, CD68 and C4d were determined with immunohistochemistry., Results:  Apart from the typical diffuse alveolar damage and hyaline membrane observed in severe influenza infection, we detected H7N9 RNA and massive intrapulmonary production of IP-10 and IL-6 mRNA using in situ hybridisation. Hyperplasia of type II pneumocytes was observed by H&E staining and immunohistochemistry. Proliferating macrophages and clustered neutrophils in the infected lungs were observed, whereas T lymphocytes, especially CD4T helper cells, were markedly depleted. No obvious complement deposition was found in lung tissues., Conclusions:  Our findings suggest that H7N9 influenza virus induced an immunological response towards overt pulmonary inflammation and systemic lymphopenia which led to intense alveolar damage and respiratory failure., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

Objectives: To evaluate surfactant content and function through the lamellar body count (LBC) and stable microbubble test (SMT) in mechanically ventilated infants with severe acute viral bronchiolitis., Study Design: Controlled cross-sectional study of 32 infants receiving mechanical ventilation: 16 with a diagnosis of acute viral bronchiolitis and 16 with normal lungs. Tracheal fluid was collected and LBC was performed in an automated cell counter. Samples were kept frozen and thawed for testing. At the time of analysis, samples were diluted in a dithiothreitol solution, vortexed for 10 seconds, and aspirated by the cell counter. SMT was performed using the Pattle technique., Results: In the bronchiolitis group, the median (IQR) LBC was significantly lower than in the control group: 130,000 (61,250-362,250) vs. 518,000 (180,250-896,000) lamellar bodies/μL; P = .003. Median (IQR) SMT values were also significantly lower in the bronchiolitis group: 10 (2-13) vs. 400 (261-615) microbubbles/mm2; P < .001., Conclusions: Infants with acute viral bronchiolitis have reduced surfactant content and function. We speculate that these simple tests may be useful to identify infants with bronchiolitis who would benefit from surfactant replacement therapy., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Background: Sustained inflation (SI) at birth facilitates establishment of functional residual capacity (FRC) in the preterm lung, but the ideal lung recruitment strategy is unclear. We have compared the effect of SI and a stepwise positive end-expiratory pressure (PEEP; SEP) strategy in a preterm model., Methods: 127 d gestation lambs received either 20-s SI (n = 9) or 2 cmH2O stepwise PEEP increases to 20 cmH2O every 10 inflations, and then decreases to 6 cmH2O (n = 10). Ventilation continued for 70 min, with surfactant administered at 10 min. Alveolar-arterial oxygen gradient (AaDO2), compliance (C(dyn)), end-expiratory thoracic volume (EEVRIP; respiratory inductive plethysmography), and EEV and C(dyn) in the gravity-dependent and nondependent hemithoraces (electrical impedance tomography) were measured throughout. Early mRNA markers of lung injury were analyzed using quantitative real-time PCR., Results: From 15 min of life, AaDO2 was lower in SEP group (P < 0.005; two-way ANOVA). SEP resulted in higher and more homogeneous C(dyn) (P < 0.0001). Mean (SD) EEVRIP at 5 min was 18 (9) ml/kg and 6 (5) ml/kg following SEP and SI, respectively (P = 0.021; Bonferroni posttest); this difference was due to a greater nondependent hemithorax EEV. There was no difference in markers of lung injury., Conclusion: An SEP at birth improved gas exchange, lung mechanics, and EEV, without increasing lung injury, compared to the SI strategy used.

Weightlessness produces adaptive and maladaptive changes in the respiratory system. We assessed the effects of 30-day antiorthostatic hanging as a model of microgravity on the water balance in the lungs and surface activity and phospholipid composition of pulmonary surfactant in C57Bl/6 mice. Long-term antiorthostatic hanging increased water content in the lungs and reduced surface-active properties of the surfactant. This was accompanied by an increase in the content of alveolar phospholipids and changes in their fractional composition (increase in the relative content of lysophosphatidylcholine and phosphatidylethanolamine).

Repeated bacterial and viral infections are known to contribute to worsening lung function in several respiratory diseases, including asthma, cystic fibrosis, and chronic obstructive pulmonary disease (COPD). Previous studies have reported alveolar wall cell apoptosis and parenchymal damage in adult pulmonary VEGF gene ablated mice. We hypothesized that VEGF expressed by type II cells is also necessary to provide an effective host defense against bacteria in part by maintaining surfactant homeostasis. Therefore, Pseudomonas aeruginosa (PAO1) levels were evaluated in mice following lung-targeted VEGF gene inactivation, and alterations in VEGF-dependent type II cell function were evaluated by measuring surfactant homeostasis in mouse lungs and isolated type II cells. In VEGF-deficient lungs increased PAO1 levels and pro-inflammatory cytokines, TNFα and IL-6, were detected 24 h after bacterial instillation compared to control lungs. In vivo lung-targeted VEGF gene deletion (57% decrease in total pulmonary VEGF) did not alter alveolar surfactant or tissue disaturated phosphatidylcholine (DSPC) levels. However, sphingomyelin content, choline phosphate cytidylyltransferase (CCT) mRNA, and SP-D expression were decreased. In isolated type II cells an 80% reduction of VEGF protein resulted in decreases in total phospholipids (PL), DSPC, DSPC synthesis, surfactant associated proteins (SP)-B and -D, and the lipid transporters, ABCA1 and Rab3D. TPA-induced DSPC secretion and apoptosis were elevated in VEGF-deficient type II cells. These results suggest a potential protective role for type II cell-expressed VEGF against bacterial initiated infection., (Copyright © 2012 Wiley Periodicals, Inc.)

In children with acute lung injury the endogenous surfactant system is altered via a variety of different mechanisms, including inflammation, vascular dysfunction, oxidant injury, cellular injury and oedema. This article examines the pathophysiology of acute lung injury and surfactant use for treatment of acute respiratory failure in infants and children.

Background: The optimal approach to detection of surfactant deficiency in the prematurely born infants at birth remains unclear and the decision to apply exogenous surfactant is based mainly on the development of clinical and radiological signs of neonatal respiratory distress syndrome (NRDS)., Objectives: We studied the biochemical and biophysical properties of gastric aspirates (GA) from prematurely born infants with NRDS and healthy full term infants with an aim to find an approachable method for assessment of surfactant maturity at birth., Material and Methods: Forty-seven newborn infants divided into two groups were enrolled in the study. The first group comprised 34 healthy infants born at term (after 37 weeks of gestation). The second group included 13 premature infants (aged from 26 to 32 weeks of gestation) developing clinical signs of NRDS for which they were treated by assisted ventilation and exogenous surfactant. A biochemical analysis of the protein and lipid content of GA collected at birth was performed. The fatty acid composition of the GA samples was determined by Gas Chromatography-Mass Selective Detector (GS-MSD) analysis. The surface characteristics (equilibrium, maximal and minimal surface tension values) of the GA samples were measured by using the pending drop method. Data were compared between the groups by using Student's t test or Mann-Whitney analysis. Values were considered significantly different if the p value was = 0.05., Results: The mean phospholipids' concentration in GA of the premature infants was lower (295.7 µg / ml vs. 374.5 µg / ml) than in the term infants and the mean protein content was less in GA of the premature babies than the term newborns (574.5 µg / ml vs. 641.5 µg / ml). The measurement of dynamic surface characteristics of GA showed significantly higher mean values of the minimal surface tension (γmin) in the premature infants - 20.5 m / Nm compared to the term babies - 12.3 mN/m (p < 0,01). There was no difference between the equilibrium surface tensions (38 mN/m vs. 38 mN/m) of both groups; The mean values of maximal surface tension (?max) in GA did not differ significantly between the groups (50.1 mN/m vs. 48.5 mN/m)., Conclusion: Our findings revealed lower phospholipids' and protein concentrations in the GA at birth from premature infants as compared to the healthy term infants. The dynamic surface characteristics of GA had significant differences between the two groups, the minimal surface tension being the most important parameter for evaluation of surfactant maturity. It could be used in the clinical practice for fast surfactant's assessment in the premature infants in regard to administration of exogenous surfactant.

Objective: To study the changes to surfactant proteins in the serum and bronchoalveolar lavage fluids (BALF) of children with Mycoplasma pneumoniae pneumonia (MPP) and their significance., Methods: Self-control method was used in the study. Forty-seven MPP children were divided into single lung infected (n=32) and bilateral lung infected groups (n=15) according to lung CT results. Surfactant proteins SP-A, B, C and D were measured using ELISA in the serum and BALF in the two groups. The correlations between SP-A, B, C and D content in the serum and BALF were evaluated by Spearman correlation analysis., Results: SP-A, B, C and D content in BALF from the majorly infected or infected lung were significantly higher than from the opposite lung and serum (P<0.01). SP-A, B and C content in serum was significantly lower than in BALF from the non-infected lung in the single-side infected lung group (P<0.01 or 0.05), but there was no significant difference between serum SP-D content and BALF SP-D content from the non-infected lung. There were no significant differences in SP-A, B, C and D content in serum and BALF from the minorly infected lung in the bilateral lung infected group. Serum SP-D content was positively correlated with BALF SP-D content from the majorly infected lung in the bilateral lung infected group (P<0.01)., Conclusions: Serum SP-D content may serve as a biomarker for evaluating the severity of pulmonary infection in children with community-acquired pneumonia.

The regional distribution of inflammation during acute lung injury (ALI) is not well known. In an ovine ALI model we studied regional alveolar inflammation, surfactant composition, and CT-derived regional specific volume change (sVol) and specific compliance (sC). 18 ventilated adult sheep received IV lipopolysaccharide (LPS) until severe ALI was achieved. Blood and bronchoalveolar lavage (BAL) samples from apical and basal lung regions were obtained at baseline and injury time points, for analysis of cytokines (IL-6, IL-1β), BAL protein and surfactant composition. Whole lung CT images were obtained in 4 additional sheep. BAL protein and IL-1β were significantly higher in injured apical vs. basal regions. No significant regional surfactant composition changes were observed. Baseline sVol and sC were lower in apex vs. base; ALI enhanced this cranio-caudal difference, reaching statistical significance only for sC. This study suggests that apical lung regions show greater inflammation than basal ones during IV LPS-induced ALI which may relate to differences in regional mechanical events., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Lamellar body count (LBC) in amniotic fluid is a well-established method for assessing fetal lung maturity. However, the biogenesis and function of lamellar bodies (LBs) secreted into the amniotic fluid have not been formally assessed. We purified LBs from amniotic fluids obtained from term gestation pregnancies that had been determined to have mature LBC. Using tandem mass spectrometry, we identified 122 unique proteins in the LB preparations from the amniotic fluids. There was minimal overlap between the proteins identified in amniotic fluid LB and those reported for human epidermis LB. In contrast, there was >40% concordance with the proteome of rat lung LBs despite species differences. Classification of the identified proteins into functional bins demonstrated that the preponderance of amniotic fluid LB proteins was associated with host defense or anti-inflammatory functions. These data suggest that amniotic fluid LBs are derived from lung secretions and may play an important role in innate host defense of the fetus., (Copyright © 2012 Thieme Medical Publishers, Inc., 333 Seventh Avenue, New York, NY 10001, USA.)

Objectives: To evaluate the performance of lamellar body count in tracheal aspirates from intubated preterm babies to predict respiratory distress syndrome., Design: Case-control study., Setting: Three neonatal intensive care units., Patients: Seventy-two patients not older than 3 days were included in the study, 38 preterm infants with respiratory distress syndrome, 16 preterms without respiratory distress syndrome, and 18 term infants. All required mechanical ventilation., Interventions: Lamellar body count was performed in an automated cell counter. Tracheal samples were diluted in dithiothreitol without centrifugation and kept frozen at -20°C until use. Samples were placed in a dithiothreitol-containing test tube at a ratio of one part tracheal aspirate to six parts dithiothreitol solution, vortexed for 10 secs, and aspirated by the cell counter. Lamellar body count was performed using the platelet channel. All results were multiplied by seven. The stable microbubble test was done for comparison., Measurements: Lamellar body count and stable microbubble test., Main Results: Lamellar body count was significantly lower in the respiratory distress syndrome group compared with the non respiratory distress syndrome preterm group and also with the term group. The median and interquartile range obtained for lamellar body count were 38,500/μL (14,000-112,000) for the respiratory distress syndrome group, 822,500/μL (442,000-962,500) for the non respiratory distress syndrome preterm group, and 633,000/μL (322,000-1,608,000) for the term group (p < .001). The sensitivity and specificity of lamellar body count and stable microbubble test for the diagnosis of respiratory distress syndrome were calculated, taking into consideration the respiratory distress syndrome and the non respiratory distress syndrome preterm groups. Considering a cutoff point of 200,000 lamellar bodies/μL, lamellar body count sensitivity was 92.1% (95% confidence interval 78.6-98.3) and lamellar body count specificity was 93.8% (95% confidence interval 69.8-99.8). The area under the curve was 0.94 (95% confidence interval 0.84-1.00)., Conclusions: Lamellar body count and stable microbubble test can be rapidly and easily performed on tracheal aspirates and they seem to have very good performance for diagnosing respiratory distress syndrome in intubated patients.

The aim of the present study was to estimate the lung surfactant maturity by analyses of gastral aspirates (GA) from prematurely born and full-term infants. A biochemical analysis of the protein and lipid content in GA from the children groups tested was made. By thin-layer chromatography the individual phospholipids components in GA samples from prematurely born and full-term children were detected. In addition, by using the pending drop method the surface characteristics (equilibrium, maximal and minimal surface tension values) were determined. Our results showed an increase in the phospholipid and the protein concentrations in GA during pregnancy progress as well as significant differences in the individual phospholipids profile of the aspirates from prematurely born and full-term children. In case of surface characteristics a highest difference was observed for the minimal surface tension values (gammamin, m/Nm); while in the full-term children a lower surface tension was determined, in the prematurely born children significant higher values were reached, which define gammamin as the most informative from the parameters studied. Our results could find application into the clinical practice for fast surfactant maturity diagnostics in prematurely born children regarding lifesaving therapy with exogenous surfactants administration.

Unlabelled: This study was conducted to characterize the distribution of epithelial regeneration in lungs with diffuse alveolar damage (DAD) and to ascertain whether epithelial regeneration is associated with the underlying disease and/or DAD stage., Methods: Lung specimens obtained at autopsy from 18 patients were studied using p63, PE-10 and Ki-67 immunostaining. The patients were categorized into two groups: patients with acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF; IPF group) and patients without IPF (non-IPF group)., Results: p63-positive cells were mostly observed in the alveolar ducts. No significant difference in the appearance of the p63-positive cells was observed between the IPF and non-IPF groups or between the exudative and the proliferative stages. PE-10-positive cells were observed in the alveoli. The number of PE-10-positive cells was significantly higher during the proliferative stage than during the exudative stage. However, p63-positive cells and PE-10-positive cells appeared at day 6 in the earliest case during the exudative stage and Ki-67-positive cells were observed during the exudative stage., Conclusion: Epithelial regeneration was not associated with the underlying disease. This study revealed that regenerative epithelial cells appeared at day 6 during the exudative stage and that the number of type Ⅱ pneumocytes increased significantly during the proliferative stage.

Objective: To evaluate surfactant production and function in term neonates with transient tachypnea of the newborn (TTN)., Study Design: Samples of gastric aspirates collected within 30 minutes of birth from 42 term newborns with gestational age ≥ 37 weeks (21 patients with TTN and 21 control subjects), delivered via elective cesarean delivery, were analyzed with lamellar body count and stable microbubble test., Results: Results of lamellar body counts and stable microbubble tests were significantly lower in the TTN group than in control subjects (P = .004 and .013, respectively). Lamellar body counts were significantly lower in infants with TTN requiring oxygen for ≥ 24 hours after birth than in infants requiring oxygen for < 24 hours (P = .029). When the cutoff point was 48 hours, the stable microbubble count was significantly lower in the group requiring oxygen for ≥ 48 hours than in the group requiring oxygen for < 48 hours (P = .047)., Conclusions: Term infants with TTN had low lamellar body counts associated with decreased surfactant function, suggesting that prolonged disease is associated with surfactant abnormalities., (Copyright © 2011 Mosby, Inc. All rights reserved.)

Objective: Metabolomics is a technique used to non-invasively determine a snapshot of the current metabolic status of an organism by analyzing intact tissue or bio-fluids. The aim of the present preliminary study was to analyze metabolic profiles in preterm infants complicated by respiratory distress syndrome (RDS) trough bronchoalveolar lavage fluid (BALF) measurement., Methods: Twelve BALF samples collected at birth prior surfactant, post-surfactant during mechanical ventilation and at extubation time-points, were analyzed by proton nuclear magnetic resonance spectroscopy and Gas chromatography-Mass Spectrometry (GC-MS)., Results: GC-MS analysis identified 25 metabolites of whom 10 had a known molecular structure. They were: undecane, decanoic acid, dodecanoic acid, hexadecanoic acid, octadecanoic acid, hexadecanoic acid methyl ester, 9-octadecanoic acid, tetracosanoic acid, myristic acid, phosphate. These metabolites were over-expressed in BALF collected during mechanical ventilation after surfactant administration., Conclusions: The present preliminary data suggest that metabolic profile in BALF of RDS infants is becoming possible opening a new cue of metabolomics as promising tool in management of sick premature infants.

The production of surfactant is a key step in fetal lung development. Surfactant decreases alveolar surface tension, thereby preventing alveolar collapse and allowing efficient gas exchange. The lack of adequate amounts of lung surfactant results in respiratory distress syndrome. Tests that assess surfactant concentrations in amniotic fluid are good predictors of infants that will not develop respiratory distress syndrome. The most frequently used test to assess fetal lung maturity (TDx FLM II) will not be available after December 2011. Therefore, we review the currently available tests for fetal lung maturity including lecithin:sphingomyelin ratio, phosphatidyl glycerol, surfactant:albumin ratio and lamellar body counts. Herein, we discuss their clinical utility and consider a suitable replacement for the future.

Background: The surfactant/albumin ratio is a popular fetal lung maturity (FLM) test that will be unavailable in the near future. We conducted surveys of obstetricians and clinical laboratorians to assess FLM testing trends from the perspectives of both disciplines and to identify how both communities might adapt to the loss of the surfactant/albumin ratio., Methods: 2067 physicians were surveyed about their familiarity with and clinical utility of various FLM tests. 6137 laboratorians were surveyed about their FLM test menu and volumes., Results: Twenty-five percent of physicians indicated a decrease in FLM test ordering and the frequency of FLM testing has decreased significantly (p=0.011) since 1998. The surfactant/albumin ratio is the most frequently offered FLM test and was the test of choice for 62% of physicians. Without the surfactant/albumin ratio, 68% of physicians would order the lecithin/sphingomyelin ratio and 44% would order the lamellar body count (LBC) which were offered by 18 and 13% of laboratories, respectively. 16% of laboratories were planning to offer the LBC within 24 months., Conclusions: FLM testing is decreasing. The loss of the surfactant/albumin ratio will increase the demand for the lecithin/sphingomyelin ratio and the LBC, yet few laboratories offer either test and most are not planning to offer the LBC., (2010 Elsevier B.V. All rights reserved.)

Introduction: Respiratory distress syndrome of the newborn caused by the fetal lung immaturity is a very serious clinical problem. Different tests of prenatal analysis of amniotic fluid, such as lamellar body count and Clements' test, are available for predicting the fetal lung maturity., Material and Methods: A prospective clinical study was conducted on amniotic fluid samples from 2005 to 2006. The amniotic fluid samples were obtained at the gestational age of 30 to 42 weeks and collected by vaginal amniotomy, amniotomy during Caesarean section and 72 hours before the delivery by amniocentesis. A haematology analyzer (Nikon - Kohden) was used to determine the lamellar body counts. Clements' test involved adding an equal volume of 96% ethanol to the multiple amniotic fluid volume (1:2, 1:4, 1:16. 1:32), followed by shaking and noting the presence of ring of bubbles. After the delivery, we compared the lamellar body count results and Clements' test and the outcome of pregnancies, primarily the development of respiratory distress syndrome. The most specific lamellar body cutoffs for maturity and immaturity were determined according to receiver operating characteristic curves., Results and Discussion: Out of 232 amniotic fluid samples which were tested, 112 samples were collected after vaginal amniotomy, 88 during the Caesarean delivery and 32 samples by amniocentesis. The overall incidence of respiratory distress syndrome was 14.6%. Receiver operating characteristic curves were used to identify cutoff points for the test. We found that both tests are good screening tests for predicting the fetal lung maturity with the area under the curve of 0.782 in Clements' test and 0.751 in the lamellar body count. Clements' cutoff 2 with sensitivity of 67.6% and specificity of 72.2%, proved best in the prediction of the fetal lung maturity. The lamellar body count cutoff of 42 x 10(3)/microl had the sensitivity of 82.4% and specificity of 64.6% in predicting the fetal lung maturity., Conclusion: Although both tests are good in predicting the fetal lung maturity, the lamellar body count has more advantages, because it is not only more objective, but also inexpensive, easy and fast to do, requires a small sample volume and is universally available.

Objective: The detection of amniotic lamellar bodies (LB) has been shown to be a rapid and simple way to assess fetal lung maturity (FLM). The maturity thresholds for LB vary due to different factors, one being the type of particle-count analyser used., Material and Methods: The Sysmex XE-2100 hematological analyser was evaluated in determination of amniotic LB counts and compared with lecithin/sphingomyelin (L/S) and phosphatidylglycerol (PG) determination. We analysed 132 amniotic samples from a total of 109 mothers (71 diabetic) with 112 infants. Results. The correlation between the LB counts obtained with the Sysmex XE-2100 and our reference thin layer chromatography (TLC) phospholipid method was good. Samples with low L/S ratio (< or = 2.0) and no PG (i.e. premature fetal lung status), had low LB counts (n = 18, mean 8500/L, range 1000-26000), whereas 51 samples with mature fetal lung status had high LB counts (mean 63600/uL, range 20,000-139,000). In all our four cases of respiratory distress syndrome the LB counts were low (range 1000-28000/uL). The reference values for FLM determination were established: < or = 6000/microL for immature, values between 7000 and 35,000/uL for borderline results and >35,000/uL for mature. CONCLUSIONS. The amniotic LB count analysis with Sysmex XE-2100 has many advantages being a repeatable, inexpensive and quantitative method with a very short turn-around time. Consequently, our routine is to perform LB counts initially from all amniotic samples and only borderline LB results are analysed with TLC.

Introduction: Respiratory distress syndrome (RDS) of the newborn infant caused by immaturity of fetal lung is a very serious clinical problem. Surfactant is stored in the form of lamellar bodies. They are secreted into alveolar space and passed into amniotic fluid where they can be found. The similarity of lamellar body size to platelet size permits the use of a standard automated hematologic cell counter to estimate the number of lamellar bodies in amniotic fluid., Material and Methods: We conducted a prospective clinical study from 2005-2006 on amniotic fluid samples. Amniotic fluid samples were collected near delivery by transvaginal amniotomy, amniotomy during Cesarean section and 72 hours before delivery by amniocentesis. A hematology analyzer (Nikon-Kohden) was used to determine the lamellar body counts. After birth of newborns we compared their complete clinical examination results particularly emphasizing the prediction of the method of RDS by lamellar body count. Maximally specific lamellar body cutoffs for maturity and immaturity were determined using ROC curves., Results and Discussion: Of 232 amniotic fluid samples which were tested, 112 samples were collected by transvaginal amniotomy, 88 were taken during Cesarean delivery and 32 samples were collected by amniocentesis. The incidence of RDS was 14.6%. ROC curves were used to identify cut points for the test. We found that LBC is a good screening test for predicting fetal lung maturity with the area under the curve of 0.751. LBC cutoff of 42 x 10(3)/microl, with sensitivity of 82.4% and specificity of 64.6%, proved best for predicting fetal lung maturity., Conclusion: LBC is a good screening test for predicting fetal lung maturity. The advantages of LBC are speed, objectivity, low price, low sample volume required and universal availability.

The lamellar body count (LBC) represents an alternative method to the TDx-FLM II (Abbott Laboratories, Abbott Park, IL), which is planned to be discontinued, for assessing fetal lung maturity. Our objective was to validate the LBC on 3 hematology analyzers (Coulter LH 750 and Coulter Ac.T diff2, Beckman Coulter, Brea, CA; and Sysmex XE-2100, Sysmex, Mundelein, IL) to serve as a template for other laboratories attempting to perform in-house validation. Intra-assay and interassay coefficients of variation ranged from 1.7% to 21.8% and 1.9% to 7.1%, respectively, and all analyzers demonstrated excellent linearity. Whole blood and meconium were shown to interfere with LBCs, and specimens with these contaminants should be tested using phosphatidyl glycerol. With a TDx-FLM II cutoff of 55 mg/g or more and an LBC cutoff of 50,000/microL or more for maturity, concordance between the TDx-FLM II and the LBC on all instruments was poor (<80% in all cases). Concordance between hematology analyzers was excellent (>or=94%). When laboratories are performing in-house validations, they should not correlate LBC with TDx-FLM II results without outcome data. Correlation with another validated LBC method is preferred.

Objectives: The purposes of this study were to quantify the time and effort involved in obtaining prenatal consent for the Neonatal Research Network Surfactant Positive Airway Pressure and Pulse Oximetry Randomized Trial (SUPPORT) and to determine whether the enrolled infants were representative of the eligible population., Methods: Eligible subjects were likely to deliver in the SUPPORT gestational age window (24-27(6/7)] weeks). Data included who approached the subjects for consent, how often they approached, the duration of each contact, whether consent was obtained, and whether subjects were enrolled in the trial. Eligible, nonenrolled infants entered into the Neonatal Research Network Generic Database throughout the period of SUPPORT enrollment were compared with enrolled infants., Results: A total of 2826 women were identified at 18 sites, 2228 were approached for consent, and 1219 (54.7%) agreed. For 76.9% of those approached, <3 visits (mean: 2.0 +/- 1.2 visits) were required to complete the consent process. Of the 659 infants with consent who were delivered within the study window, 611 were enrolled. Mothers who received a neonatal consultation were more likely to give consent (P < .001). The proportion of infants not exposed to steroids was significantly greater in the nonapproached group than in the approached group (20.0% vs 3.4%; P < .0001)., Conclusion: In a trial that involved preterm infants and required prenatal consent, >5 women were identified as being likely to deliver in the SUPPORT gestational age window for each 1 who delivered an enrolled infant.

Even though artificial surfactant is now available, respiratory distress syndrome still remains a serious problem in neonatology. Prenatal analysis of the amniotic fluid can provide data giving insight into the fetal lung maturity, which enables planning of the further outcome of high-risk pregnancies. Surfactant prevents atelectasis by forming a layer rich in phospholipids between the air and liquid phase in alveoli thus leading to increased surface tension in them, which is a precondition for a good lung function after birth. Lamellar bodies are a form of stored surfactant, and their count in the amniotic fluid can be determined simply by a standard hematology analyzer. The method of determining lamellar body count has found an important place in prenatal diagnostics and is recommended as an initial method of a "cascade" procedure of testing fetal lung maturity. However, considering the importance of procedure of sample collection, storage and centrifugation, which can significantly affect the results obtained for the lung maturity, the amniotic fluid samples must be absolutely free of contamination with blood, meconium, mucus, bacteria and leucocytes.

Objective: Glucocorticoid administration to women in preterm labor improves neonatal mortality and morbidity. Fetal exposure to glucocorticoid levels higher than those appropriate to the current gestational stage has multiple organ system effects. Some, eg, fetal hypertension, are maximal at lower than the clinical dose. We hypothesized that the clinical dose has supramaximal lung maturational effects., Study Design: We evaluated the full, half, and quarter clinical betamethasone dose (12 mg/70 kg or 170 microg/kg intramuscularly twice 24 hours apart) on fetal sheep lung pressure volume curves (PVC) after 48 hours' exposure at 0.75 gestation. We measured key messenger RNAs and protein products that affect lung function and total lung dipalmitoyl phosphatidyl choline., Results: Full and half doses had similar PVC and total lung dipalmitoyl phosphatidyl choline effects. Messenger RNA for surfactant proteins A, B, and D and elastin increased in a dose-dependent fashion., Conclusion: Half the clinical betamethasone dose produces maximal PVC improvement in fetal sheep at 0.75 gestation., (Copyright 2010 Mosby, Inc. All rights reserved.)