Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0476273 (respiratory distress)
 19,632 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Surfactant preparations have been proven to improve clinical outcome of infants at risk for or having respiratory distress syndrome (RDS). In clinical trials, ani mal-derived surfactant preparations reduce the risk of pneumothorax and mortality when compared to non-protein-containing synthetic surfactant preparations. In part, this is thought to be due to the presence of surfactant proteins in animal-derived surfactant preparations. Four native surfactant proteins have been identified. The hydrophobic surfactant proteins B (SP-B) and C (SP-C) are tightly bound to phospholipids. These proteins have important roles in maintaining the surface tension-lowering properties of pulmonary surfactant. Surfactant protein A (SP-A) and D (SP-D) are extremely hydrophilic and are not retained in the preparation of any commercial animal-derived surfactant products. These proteins are thought to have a role in recycling surfactant and improving host defense. There is concern that animal-derived products may have some batch-to-batch variation regarding the levels of native pulmonary surfactant proteins. In addition, there is concern regarding the hypothetical risk of transmission of viral or unconventional infectious agents from an animal source. New surfactant preparations, composed of synthetic phospholipids and essential hydrophobic surfactant protein analogs, have been developed. These surfactant protein analogs have been produced by peptide synthesis and recombinant technology to provide a new class of synthetic surfactants that may be a suitable alternative to animal-derived surfactants. Preliminary clinical studies have shown that treatment with these novel surfactant preparations can ameliorate RDS and improve clinical outcome. Clinicians will need to further understand any differences in clinical effects between available products.
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PMID:New synthetic surfactants: the next generation? 1598 57

Epithelial cells lining the peripheral lung synthesize pulmonary surfactant that reduces surface tension at the air-liquid interface. Lack of surfactant lipids and proteins in the lungs causes respiratory distress syndrome, a common cause of morbidity and mortality in preterm infants. We show that C/EBPalpha plays a crucial role in the maturation of the respiratory epithelium in late gestation, being required for the production of surfactant lipids and proteins necessary for lung function. Deletion of the Cebpa gene in respiratory epithelial cells in fetal mice caused respiratory failure at birth. Structural and biochemical maturation of the lung was delayed. Normal synthesis of surfactant lipids and proteins, including SP-A, SP-B, SP-C, SP-D, ABCA3 (a lamellar body associated protein) and FAS (precursor of fatty acid synthesis) were dependent upon expression of the C/EBPalpha in respiratory epithelial cells. Deletion of the Cebpa gene caused increased expression of Tgfb2, a growth factor that inhibits lung epithelial cell proliferation and differentiation. Normal expression of C/EBPalpha required Titf1 and Foxa2, transcription factors that also play an important role in perinatal lung differentiation. C/EBPalpha participates in a transcriptional network that is required for the regulation of genes mediating perinatal lung maturation and surfactant homeostasis that is necessary for adaptation to air breathing at birth.
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PMID:C/EBPalpha is required for lung maturation at birth. 1646 60

Pulmonary surfactant, a complex of lipids and proteins, functions to keep alveoli from collapsing at expiration. Surfactant proteins A (SP-A) and D (SP-D) belong to the collectin family and play pivotal roles in the innate immunity of the lung. Pulmonary collectins directly bind with broad specificities to a variety of microorganism and possess anti-microbial effects. These proteins also exhibit both inflammatory and anti-inflammatory functions, which occur through interactions with pattern recognition receptors including Toll-like receptor and CD14, signal inhibitory regulatory protein alpha and a receptor complex of calreticulin and CD91. The collectins enhance phagocytosis of microbes by macrophages through opsonic and/or non-opsonic activities. The proteins stimulate cell surface expression of phagocytic receptors including scavenger receptor A and mannose receptor. Since the expression of SP-A and SP-D is abundant and restricted within the lung, the proteins are now clinically used as biomarkers for lung diseases. The levels of SP-A and SP-D in bronchoalveolar lavage fluids, amniotic fluids, tracheal aspirates and pleural effusions reflect alterations in alveolar compartments and epithelium, and lung maturity. The determination of SP-A and SP-D in sera is a non-invasive and useful tool for understanding some pathological changes of the lung in the diseases, including pulmonary fibrosis, collagen vascular diseases complicated with interstitial lung disease, pulmonary alveolar proteinosis, acute respiratory distress syndrome and radiation pneumonitis.
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PMID:Pulmonary surfactant proteins A and D: innate immune functions and biomarkers for lung diseases. 1647 50

Here, we describe the approach of defining the genetic contribution to disease and discuss the polymorphisms of some genes that are associated with respiratory disease. The common allelic variants of SP-A1, SP-A2, SP-B, SP-C, and SP-D genes are associated with respiratory distress syndrome (RDS), bronchopulmonary dysplasia (BPD), or respiratory syncytial virus (RSV) bronchiolitis. The main SP-A haplotype, interactively with SP-B Ile131Thr polymorphism and with constitutional and environmental factors, influences the risk of RDS. The polymorphisms of SP-A2 and SP-D are associated with the risk of severe RSV. The polymorphism may turn out to be important in susceptibility to influenza virus. The SP-B intron 4 deletion variant is the risk factor of BPD. Understanding the molecular mechanisms behind the hereditary risk may lead to new focused treatment strategies.
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PMID:Surfactant protein polymorphisms and neonatal lung disease. 1714 61

Lung surfactant is a complex mixture of phospholipids and four surfactant-associated proteins (SP-A, SP-B, SP-C and SP-D). Its major function in the lung alveolus is to reduce surface tension at the air-water interface in the terminal airways by the formation of a surface-active film enriched in surfactant lipids, hence preventing cellular collapse during respiration. Surfactant therapy using bovine or porcine lung surfactant extracts, which contain only polar lipids and native SP-B and SP-C, has dramatically improved the therapeutic outcomes of preterm infants with respiratory distress syndrome (RDS). One important goal of surfactant researchers is to replace animal-derived therapies with fully synthetic preparations based on SP-B and SP-C, produced by recombinant technology or peptide synthesis, and reconstituted with selected synthetic lipids. Here, we review recent research developments with peptide analogues of SP-B and SP-C, designed using either the known primary sequence and three-dimensional (3D) structure of the native proteins or, alternatively, the known 3D structures of closely homologous proteins. Such SP-B and SP-C mimics offer the possibility of studying the mechanisms of action of the respective native proteins, and may allow the design of optimized surfactant formulations for specific pulmonary diseases (e.g., acute lung injury (ALI) or acute respiratory distress syndrome (ARDS)). These synthetic surfactant preparations may also be a cost-saving therapeutic approach, with better quality control than may be obtained with animal-based treatments.
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PMID:Hydrophobic surfactant proteins and their analogues. 1757 74

The metabolism, composition, structure and functions of the alveolar surfactant (AS) are described. The most adequate biophysical models for investigation of AS are considered. The principals and possibilities of three mostly used models are described in details: Monolayers, Spinning drop method and Thin liquid films. Some of the studies of Bulgarian biophysical, physicochemical, biochemical and medical groups on the structure and mechanism of action of AS in vivo using samples of amniotic fluid (AF), animal pulmonary lavages (PL) and tracheal aspirates (TA) of newborns and adults are summarized. The role of specific surfactant proteins (SP-A, SP-B, SP-C and SP-D) on the properties and function of AS is demonstrated. The opportunities of the model investigations for application in laboratory pre- and postnatal diagnosis of the respiratory distress syndrome (RDS), as well as for the efficiency of RDS therapy during exogenous surfactant therapy with ALEC (UK), Survanta (USA), Exosurf (USA), Curosurf (Italy) u Alveofact (Germany) are considered.
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PMID:[Pulmonary surfactants: in vivo structure and in vitro biophysical models for investigation and its perspectives]. 1817 10

Preterm and young neonates have an increased predisposition to respiratory distress syndrome (RDS) associated with an immature development of lung surfactant. Glucocorticoids (GCs) are the major immunomodulatory agents used to increase lung development and reduce the mortality and morbidity of preterm infants with RDS. However, their safety remains uncertain, and the precise mechanisms by which they improve lung function are unclear. In previous studies, we found that vascular endothelial growth factor (VEGF) enhances the innate immune response by respiratory epithelial cells, causes a monocytic infiltration into the lung, and reduces the severity of infection by respiratory syncytial virus (RSV), a respiratory pathogen known to affect preterm infants at a high prevalence. The purpose of this study is to measure the effects of VEGF administration on local immune responses in neonatal lambs, as the ovine lung is well suited for comparison to the human lung, due to similarities in alveolar development, immune responses, and RSV susceptibility. We hypothesized that VEGF induces the expression of genes necessary for host immune responses. We analyzed global gene expression profiles in the lungs of neonate lambs treated with VEGF by real-time qPCR. We report that VEGF induced the expression of chemokines (IL-8, RANTES, MCP-1), cytokines (IFN-gamma, IL-6, TNF-alpha, GMCSF), Toll-like receptor (TLR)-4, complement family members (C3, CFB, CFH) and collectins (SP-A, SP-D). These results suggest that VEGF can regulate local immune gene expression in vivo and should be further explored as a potential exogenous therapy for various lung diseases.
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PMID:Gene profiling studies in the neonatal ovine lung show enhancing effects of VEGF on the immune response. 1918 46

Pulmonary surfactant-associated proteins A and D (SP-A and -D) are tissue-specific components. Previous studies showed an increase in the postmortem serum SP-A level due to acute pulmonary alveolar damage and acute respiratory distress. The present study comparatively investigated serum SP-A and SP-D levels with regard to the cause of death in serial medicolegal autopsy cases (n=679, within 48 h postmortem). SP-A and SP-D levels were usually higher in left cardiac blood than at other sites, independent of postmortem interval. The left-to-right difference was significantly larger for mechanical asphyxiation, drowning, intoxication and spontaneous cerebral hemorrhage. Both SP-A and -D levels in bilateral cardiac blood were significantly higher for drowning and secondary pulmonary damage involving ARDS after traumas, but were lower for hypothermia (cold exposure). SP-A was predominantly elevated in fire fatality and delayed deaths from injury and fires, while pneumonia showed a predominant elevation of SP-D. These findings suggest that comparative analysis of serum SP-D and SP-A is useful for investigating primary or secondary pulmonary alveolar damage in the death process.
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PMID:Postmortem serum levels of pulmonary surfactant-associated proteins A and D with regard to the cause of death in medicolegal autopsy. 1925 64

Neonatal respiratory distress syndrome (NRDS) is the commonest cause of death and morbidity of the newborn. A genetic risk for NRDS is currently recognized. The aim of this study was to determine whether there was an association of the polymorphisms of the SP-B, SP-D genes and the interleukins (IL)-1alpha, IL-10 genes with the development of infectious complications in neonatal infants with the respiratory distress syndrome. It was found that the certain genotypes by the polymorphic loci of surfactant proteins and interleukins might be associated with infectious diseases in the newborn with respiratory distress syndrome.
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PMID:[Genetic markers of predisposition to infectious complications in neonatal infants with respiratory distress syndrome]. 1934 29

Acute exacerbation of interstitial pneumonia (IP-AE) can occasionally occur and has a poor prognosis. Direct hemoperfusion with a polymyxin B immobilized fiber column (PMX-DHP) has been shown to have a beneficial effect on acute respiratory distress syndrome, which has similar pathological features to that of IP-AE. This study was aimed to investigate the effects of PMX-DHP on IP-AE and serum indicators for epithelial damage. Nine patients with a clinical diagnosis of interstitial pneumonia, who developed acute exacerbation, were included in this study. Five patients had been given a diagnosis of idiopathic pulmonary fibrosis (IPF) and 3 cases were diagnosed as collagen vascular disease-associated interstitial pneumonia (CVD-IP). On days 30 and 60, 6 and 4 patients were surviving, respectively. On day 60, all 3 patients with CVD-IP were alive, while 4 of 5 patients with IPF had died. In 4 patients who survived for 60 days or longer, serum levels of LDH, CRP, and SP-D were significantly decreased after PMX-DHP, whereas KL-6 level was unchanged. In 5 patients, who died by day 60, no significant changes in the serum markers were observed. These data suggest that serum levels of LDH, CRP, and SP-D might be predictive of successful PMX-DHP treatment in cases of IP-AE.
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PMID:[Effect of direct hemoperfusion with a polymyxin B immobilized fiber column in acute exacerbation of interstitial pneumonia and serum indicators]. 1999 91


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