Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0010200 (cough)
 23,843 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The output of secretions from the airway submucosal glands is regulated by vagal efferent nerves. Stimulation of cough receptors increases mucus output reflexly via the vagus nerves. Adrenergic agonists increase submucosal gland secretions in some species, which indicates that adrenergic receptors are present in these cells. However, evidence for adrenergic nervous pathways to the glands is limited. Irritants and drugs stimulate secretion from epithelial cells by direct effects. There is also evidence that the secretion of epithelial cells can be stimulated by parasympathetic nervous pathways in birds but not in mammals. Active ion transport of Cl- toward the lumen and of Na+ toward the submucosa results in net ion movement toward the airway lumen in unstimulated tracheal epithelia. Drugs and mediators increase the net movement of ions toward the lumen. No agents have yet been found that increase net ion movement toward the submucosa. The link between ion transport and water secretion in airway epithelia, although speculative, seems likely in view of the evidence from other epithelia. Since airway epithelium is a "tight junction" epithelium, modification of the tight junction may alter the transepithelial movement of water and ions. We suggest that the depth and consistency of the periciliary layer of airway secretions determine the ability of the cilia to propel the mucoprotein gel and thereby modify mucociliary transport. To achieve this, secretion of mucus must be controlled separately from the secretion of water. Studies are needed to determine which of the specialized functions of the epithelial cells interact to regulate the clearance of secretions from the airway. Is the sol maintained by secretion and reabsorption of fluid across the epithelium? Does the sol move with the gel by ciliary action or does it remain stationary? Do changes in the epithelial tight junctions influence net water movement and thus indirectly alter the depth of the sol layer? To answer these questions, techniques are needed to study subunits of the airway, including isolated surface cells and submucosal glands; and sensitive methods are required to analyze the very small samples of secretions for glycoprotein and electrolyte content. Intracellular measurements of electrolyte concentrations and electrical potentials may help to elucidate the mechanisms of transepithelial ion and water movement. The control system for the production and removal of respiratory tract secretions may be altered in disease. For instance, chronic stimulation of cough receptors causes reflex secretion and may be the cause of the hyperplasia of submucosal glands and of the abnormal secretions that occur in chronic bronchitis and asthma (50, 58). The abnormally viscid mucus in cystic fibrosis may be due to a defect in Cl- transport, which provides too little water for both the gel and sol layers. These speculations are intended to identify areas for further research, which hopefully will reduce the morbidity and mortality in these common lung diseases.
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PMID:Control of mucus secretion and ion transport in airways. 37 97

1. Sulphated glycoprotein output from the trachea, isolated in situ, has been measured in anaesthetized cats by a radio-isotopic method. The effects of irritation of various parts of the airway on this mucus output were studied. 2. Mechanical stimulation of the nose and nasopharynx increased tracheal mucus output by reflexes which involved parasympathetic and probably also sympathetic motor pathways. 3. Laryngeal stimulation had a similar through the same motor pathways. 4. Inhalation of ammonia vapour into the lower airways reflexly increased mucus output from the isolated trachea. The efferent pathway for this reflex was mainly or entirely parasympathetic. It is argued that the afferent pathway involved cough receptors. 5. Lung inflation, inhalation of histamine aerosol and intravenous injection of phenyl diguanide (which excite mainly lung stretch receptors, lung 'irritant' receptors and alveolar 'J-receptors' respectively) had no consistent effect on tracheal mucus secretion. 6. The afferent and efferent pathways of these reflexes are discussed.
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PMID:The effects of irritation at various levels of the airway upon tracheal mucus secretion in the cat. 97 88

Prolonged exposure of dogs to high concentrations of SO2 gas results in a syndrome with many of the characteristics of human chronic bronchitis, including cough and chronic mucous hypersecretion as well as airway obstruction. We developed and used a novel monoclonal antibody, GB-4B, raised against epithelial glycoprotein isolated from human hypersecretory mucus to probe airway lavage samples from dogs before and during prolonged exposure to SO2 gas. There were relatively low mean titers of the epitope recognized by GB-4B in airway lavage fluid as evidenced by enzyme-linked immunosorbent assay before exposure to SO2 gas. After 25 to 50 wk of SO2 exposure, the dogs showed a significant increase in pulmonary resistance and there was a significant increase in the titer of the epitope in the airway lavage fluid. Using the same antibody immunohistochemical analysis of airway tissues from SO2-exposed dogs revealed patchy staining of the mucous glands and airway secretory cells and dense staining along the airway surface; airway tissue from control dogs and one SO2-exposed dog whose lavage fluid did not contain the epitope showed little or no staining. These data demonstrate that similar mucin epitopes appear in airway lavage fluid under hypersecretory conditions in both animals and humans. The epitope may have utility as a marker of chronic mucous hypersecretion.
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PMID:Recovery of an epitope recognized by a novel monoclonal antibody from airway lavage during experimental induction of chronic bronchitis. 169 18

The transepithelial potential difference (PD) value represents an integral of ion fluxes across the epithelium, and relates to the regulation of airway fluid. We studied six healthy two day old husky puppies for their tracheal mucus rheology and bioelectric properties, since this data in newborns are still unknown. PD (-mV, epithelium vs. subcutaneous space) was measured using the agar bridge technique in two locations - lower trachea and subglottic region. For the rheological analysis, the magnetic microrheometer was employed; data are presented as mechanical impedance log G* and loss tangent tan delta (1 rad/s). The mucus collection rate (mg/min) and the solid content (%) were determined by gravimetry. Mucociliary clearability, normalized to frog mucus, (MCFP) was determined directly by the frog palate method; a cough clearability index (CCI) was computed from simulated cough machine data obtained with mucus-like gels. The mucus collection rates and PD values were considerably lower than those observed in adult dogs; the mechanical impedance values were also reduced in comparison with adult data. The PD profile within the trachea (-13.9 +/- 1.2 mV lower trachea vs. -18.4 +/- 1.4 mV subglottical, i.e. more negative subglottically), however, is similar to that observed in adult dogs. Intratracheal profiles in mucus collection rate and mucus rheology were also comparable between puppies and adult dogs. The low collection rates in puppies, particularly in lower trachea, could indicate either reduced mucus volume or slower clearance. PD and collection rate correlated very strongly (r = 0.82, p = 0.0003). PD also correlated negatively with log G* (r = 0.73, p = 0.003) and positively with tan delta (r = 0.58, p = 0.03). MCFP and % solids correlated positively (r = 0.84, p = 0.0012), in contradistinction to the usual relationship, perhaps due to the presence of non-glycoprotein components that do not contribute to crosslink formation. The apparent maturation of airway bioelectric properties, mucus collection rate and mucus viscoelasticity are all consistent with the maturation of mucociliary clearance, which has previously been reported.
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PMID:Tracheal mucus rheology and epithelial potential difference in two day old puppies. 226 17

Recent studies have shown that normal bronchial secretion composed of proteoglycans, atypical glycoproteins and neutral lipids neither includes mucins nor glycolipids, nor phospholipids. The rheological characteristics of bronchial mucus thus depend on mucociliary clearance and clearance of bronchial secretions by cough, which in turn depend on the properties of the glycoprotein acids secreted and on the degree of their entanglement which is linked to their water content and on the chemical bonds with other protein or lipid components which are present in the secretions. Chronic bronchitis, asthma and bronchorrhoea allow for changes in the biochemical composition and the physical and rheological characteristics of the bronchial mucus which alter the clearance. In certain conditions mucus plugs can form. An understanding of the pathology of bronchial mucus in the adult enables one to choose the best therapeutic prescriptions but the efficacy of measurements available remains imperfect.
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PMID:[Anomalies of mucus and bronchial pathology in adults]. 269 Feb 13

Asada-ame containing Platycodi Radix, Ginseng Radix, Ephedrae Herba and Ipecacuanhae Radix extracts has been hitherto widely used as an antitussive and expectorant. In the present study, the antitussive effect and tracheo-bronchial secretory activity of Asada-ame extract (AE) were investigated with laboratory animals. Antitussive effect was evaluated with the puncture electrode-induced cough method in conscious guinea pigs. AE showed a significant antitussive effect which lasted more than one hr. 50% Antitussive doses were 76 mg/kg, i.p., and 500 mg/kg, p.o. Airway secretory effect was evaluated with the stopper method in anesthetized dogs. With oral administration of AE, the volume of respiratory tract fluid (RTF) increased, and viscosity of RTF, which was determined using the glass plate method, was decreased in a dose-dependent manner. The effects of AE on secretory activity of canine tracheal secretory cells were investigated in vitro with the histological/histochemical technique. With AE treatment, the thickness of the acini of submucosal glands was decreased, and the ratio of acinar inner diameter of the gland to tracheal wall was increased. Furthermore, the number of acid glycoprotein-containing submucosal glandular cells was decreased by AE, suggesting a mucolytic effect of AE. The above findings indicate that AE has significant antitussive and expectorant effects.
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PMID:[Antitussive and expectorant effects of Asada-ame extract]. 372 63

The association of vitamin A supplementation with concentrations of positive acute-phase proteins in the serum was investigated in the Child Health Study of the Ghana Vitamin A Supplementation Trials, a randomized, controlled trial of the effect of vitamin A on morbidity in children aged < 5 y. Mean serum concentrations of alpha 1-acid glycoprotein, serum amyloid A, and C-reactive protein did not differ overall between the vitamin A-supplemented and placebo-treated groups. Treatment groups were then subdivided according to what symptoms children had experienced in the week before blood sampling. Acute-phase-protein responses to fever and cough were not affected by vitamin A supplementation. There was a tendency for vitamin A-supplemented children, but not placebo children, to have elevated acute-phase proteins in association with reported vomiting or severe diarrhea. The failure of unsupplemented children to mount an acute-phase response may have contributed to their increased morbidity from gastrointestinal symptoms.
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PMID:Vitamin A supplementation, morbidity, and serum acute-phase proteins in young Ghanaian children. 754 31

Work in swine confinement buildings leads to an inflammatory response and may be associated with increased levels of acute phase proteins. We compared the inflammatory response of a control group of young former farm workers with age-matched former farm workers who had previously developed the lower airway symptoms of wheeze, cough, tightness of the chest during work in swine confinement buildings, and because of these symptoms had stopped work. Both groups were subjected to an experimental exposure in a swine confinement building for 3 hours. Complement activation and acute phase proteins were measured in blood samples and broncho-alveolar lavage. Plasma C3d levels correlated with respirable dust, significantly so for individual cases and for the whole cohort. Plasma C3, fibrinogen and alpha (1) -acid glycoprotein peaked 1 and 6 h after exposure start, mannan-binding lectin, C-reactive protein and alpha(1)-antitrypsin peaked after 2 h. Surfactant protein D (SP-D) and alpha (2) -macroglobulin were downregulated. In lavage, only SP-D, alpha (2)-macroglobulin and fibronectin were detected. FEV(1), FVC, TLC and FEV(25-75) did not vary during exposure. There was complement activation in response to respiratory dust, more so amongst cases than in the control group. Acute exposure, with work related levels of organic dust containing endotoxin, leads to a weak systemic inflammatory response.
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PMID:Plasma C3d levels of young farmers correlate with respirable dust exposure levels during normal work in swine confinement buildings. 1285 33

Human metapneumovirus (hMPV), a recently described paramyxovirus, is a major etiological agent for lower respiratory tract disease in young children that can manifest with severe cough, bronchiolitis, and pneumonia. The hMPV fusion glycoprotein (F) shares conserved functional domains with other paramyxovirus F proteins that are important for virus entry and spread. For other paramyxovirus F proteins, cleavage of a precursor protein (F0) into F1 and F2 exposes a fusion peptide at the N terminus of the F1 fragment, a likely prerequisite for fusion activity. Many hMPV strains have been reported to require trypsin for growth in tissue culture. The majority of these strains contain RQSR at the putative cleavage site. However, strains hMPV/NL/1/00 and hMPV/NL/1/99 expanded in our laboratory contain the sequence RQPR and do not require trypsin for growth in Vero cells. The contribution of this single amino acid change was verified directly by generating recombinant virus (rhMPV/NL/1/00) with either proline or serine at position 101 in F. These results suggested that cleavage of F protein in Vero cells could be achieved by trypsin or S101P amino acid substitution in the putative cleavage site motif. Moreover, trypsin-independent cleavage of hMPV F containing 101P was enhanced by the amino acid substitution E93K. In hamsters, rhMPV/93K/101S and rhMPV/93K/101P grew to equivalent titers in the respiratory tract and replication was restricted to respiratory tissues. The ability of these hMPV strains to replicate efficiently in the absence of trypsin should greatly facilitate the generation, preclinical testing, and manufacturing of attenuated hMPV vaccine candidates.
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PMID:An S101P substitution in the putative cleavage motif of the human metapneumovirus fusion protein is a major determinant for trypsin-independent growth in vero cells and does not alter tissue tropism in hamsters. 1605 60

The objective was to investigate the clinical features, glycoprotein B (gB) genotype and therapy of the human cytomegalovirus (CMV)-associated idiopathic thrombocytopenic purpura (ITP) in Chinese children. Clinical features and laboratory data of 25 CMV-associated ITP, including 18 males and 7 females with a median age of 0.3 y, were analysed and compared with 116 CMV-negative ITP. The CMV gB of 17 cases was genotyped. Apart from dermatorrhagia, jaundice was noted in 6 cases. Cough, diarrhoea, fever, splenohepatomegaly, alimentary tract haemorrhage and raised ALT were also found. Compared with CMV-negative ITP, CMV-associated ITP has a younger median age, raised ALT and AST, and longer hospitalization (p<0.05, respectively). The most prevalent genotype was gB1 (15/17), followed by coinfection and gB3. Compared with congenitally CMV-infected children in our previous study, more prevalence of gB1 was noted (40/79 vs 15/17, p=0.004). Most of these cases were receiving the therapy of immunoglobulin, corticoid and/or gancyclovir with good therapeutic effect except for 2 cases. In conclusion, CMV infection, especially gB1 genotype, is an important cause of ITP and careful examination of markers of CMV in all cases of apparent 'idiopathic' ITP is required. Combination therapy of immunoglobulin, corticoid and gancyclovir is effective.
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PMID:Cytomegalovirus-associated idiopathic thrombocytopenic purpura in Chinese children. 1861 35


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