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At least 19 recordsLinked to original sources
PubMed2004

[Mucus plugs in the ventral bronchi travel less distance than those in the dorsal bronchi: HRCT observation in third-order or smaller bronchi].

PURPOSE: To examine on HRCT whether there is a difference in the respiratory moving distance of bronchial mucus plugs between ventral and dorsal bronchi. MATERIALS AND METHODS: We examined 36 ventral and dorsal bronchi of the same order in 18 patients with mucoid impaction depicted on HRCT. CT data were obtained by multidetector-row CT. HRCT images of 0.5 mm thickness and 0.3 mm interval were reconstructed. We selected one slice including a mucus plug take-off from each bronchus. When they were not included in a slice, we reconstructed a 1-3 mm slab-thickness MIP image. In these images we measured the distance between the take-off of each bronchus and the hilar margin of the mucus in same-order ventral and dorsal bronchi. We also measured CT attenuation in the ROI of the subpleural region excluding vessels in the same slice. When the differences in distances (delta D) and CT attenuations (delta C) between inspiration and expiration were obtained, we analyzed the correlation between delta D and delta C in ventral and dorsal bronchi, respectively. We also compared delta D between ventral and dorsal bronchi. RESULTS: Mean delta C was 36.26 +/- 2.78 HU. Ventral delta D was 6.46 +/- 3.75 mm, and dorsal delta D was 2.57 +/- 1.59 mm. The correlation between delta C and dorsal delta D was significant (r = -0.78, p < 0.005), whereas that between delta C and ventral delta D was not (r = 0.23, p = 0.64). The ventral delta D was significantly smaller than the dorsal (p < 0.05). CONCLUSION: Between inspiration and expiration in the supine position, mucus plugs in the ventral bronchi travel less distance than those in the dorsal bronchi.

Adult↗
PubMed1996

Effects of SCA40 on human bronchi and on guinea pig main bronchi in vitro. Comparison with cromakalim.

The aim of this study was to examine the activity of SCA40, a novel charybdotoxin-sensitive potassium channel opener, against a variety of spasmogens or against electrical field stimulation in guinea pig isolated main bronchi and in human isolated bronchi; the effects of SCA40 were compared with those of cromakalim. Like cromakalim, SCA40 reduced the contractility of guinea pig and human isolated bronchi precontracted with acetylcholine 10(-6) M or neurokinin A 10(-6) M, SCA40 being more efficient and more potent than cromakalim. Moreover, on guinea pig isolated main bronchi, SCA40 can exert a preventive effect on contractions induced by acetylcholine, neurokinin A or capsaicin, that is, it shifts to the right the concentration-effect curves of these substances, whereas cromakalim has no such effect. The effects of cromakalim were antagonized by glibenclamide 10(-5) M, whereas the effects of SCA40 were inhibited by tetraethylammonium (TEA 10(-2) M) and charybdotoxin (3 x 10(-8) M), but this inhibitory effect of TEA was reversed by nifedipine (10(-6) M). Electrical field stimulation of guinea pig isolated main bronchi induced two successive contractile responses. Both contractions were significantly reduced by SCA40 (10(-6) and 10(-5) M) and cromakalim (10(-5) M). Since cromakalim was unable to inhibit the effects of acetylcholine or neurokinin A, it might be suggested that for this latter compound the inhibition seems to take place prejunctionally and to affect the release of neuromediators produced by electrical field stimulation. In contrast, in the case of SCA40, a postjunctional effect seems to be likely, owing to its preventive effects, although a prejunctional effect cannot be excluded. Finally, on guinea pig isolated main bronchi, SCA40 (10(-8)-10(-6) M) did not potentiate the relaxant effect of isoprenaline or sodium nitroprusside, suggesting a lack of functional manifestation of inhibition of phosphodiesterase for these concentrations. In conclusion, these results demonstrate that SCA40 is a potent and efficient relaxant of guinea pig and human airway smooth muscle, and is able to inhibit, in the guinea pig isolated main bronchi, the contractions induced by electrical field stimulation. It has an effect on TEA-sensitive K+ channels, but this effect is probably not involved in its relaxant effect which does not also rest on an inhibitory effect of phosphodiesterase.

Acetylcholine↗
PubMed1998

Functional activity of bronchi from an organ donor with fatal asthma: studies on cryopreserved bronchi.

Human bronchi were taken from the lungs of a single asthmatic and 5 nonasthmatic organ donors. The tissues were slowly frozen to -70 degrees C and stored for 1-28 months in liquid nitrogen (-196 degrees C) while suspended in Krebs-Henseleit solution containing 1.8 M dimethyl sulfoxide and 0.1 M sucrose as cryoprotectants. After thawing, bronchial rings were suspended in 10 ml organ baths for isometric tension recording. Spontaneously developed tone (1.13 +/- 0.12, n = 22, vs. 0.56 +/- 0.07 g, n = 33, p < 0.001) and maximal contractile responses to histamine (1.93 +/- 0.12, n = 34, vs. 1.02 +/- 0.14 g, n = 30, p < 0.001) were significantly stronger in asthmatic than in nonasthmatic bronchi. The potency of histamine was 4 times less in asthmatic than in nonasthmatic bronchi (p < 0.001). Comparison of the maximal responses to histamine after storage at -196 degrees C for up to 28 months revealed no significant reduction of the contractile function by time of cryostorage. Salbutamol and the potassium channel opener SDZ PCO 400 were 3-4 times less potent in asthmatic than in nonasthmatic bronchi. For antagonism of histamine by ketotifen in asthmatic bronchi (pD'2 = 8.04 +/- 0.13, n = 5) 4 times higher concentrations were necessary than in nonasthmatic bronchi (pD'2 = 8.63 +/- 0.06, n = 15, p < 0.001). These data support the contention that in spite of a diminished sensitivity to histamine after fatal asthma, isolated bronchi show enhanced spontaneous and agonist-induced contractile responses whereas relaxant responses appear to be impaired.

Adult↗
PubMedDate not supplied

[The immunomorphology of the mucosa of the bronchi and gastroduodenal zone in children with combined disease of the bronchi and gastrointestinal tract].

Mucous membrane of the bronchi, antral zone of the stomach and duodenum were studied histologically, morphometrically, immunohistochemically and bacterioscopically in 47 children of 5 to 14 years of age with bronchial asthma (16 patients), obstructive bronchitis (12 patients), chronic pneumonia or chronic nonspecific bronchitis (19 patients). All these children had also gastroduodenitis. There was an increase of local production of IgE and enhanced degranulation of mast cells in bronchial mucosa and gastroduodenal zone in children with bronchial asthma and obstructive bronchitis. The proportion of CD4+/CD8+ decreased to 0.92 in bronchial asthma. Gastritis was associated much more frequently with Helicobacter pylori in children with chronic obstructive bronchitis and bronchial asthma.

Adolescent↗
PubMedDate not supplied

[Research on the occurrence of functional anomalies of the peripheral bronchi (small bronchi disease) in workers in a factory with respiratory noxious substances].

A group of 908 subjects has been studied, of which two-thirds were males, classified in 5 categories: unexposed, with light exposure, and severely exposed to inhalation of volatile substances, or various types of dust. A B.M.R.C. file was filled for each of the subjects. This file concerns respiratory symptoms. A forced expirogram was also performed, and FEV 25-75%, FEV 75-85%, and TEM were determined. The two expiratory flows (median and final) are frequently disturbed in subjects without respiratory symptoms, more frequently in smokers with a normal FEV 1. In those exposed to respiratory risk the proportion of alterations increases, but association of smoking with inhalation of noxious chemical substances will determine a modification of FEW 1 and anomalies of the peripheral bronchi occur more frequently in smokers. Between the criteria suggesting the presence of small airways disease, the ratio FEV 25-75% under 60%, with a FEV 1/FVC ratio within normal limits, this being the most sensitive of the criteria, also appears as the most reliable.

Adult↗
PubMed1995

Postvagotomy changes in neurogenic plasma extravasation in rat bronchi.

The present study was carried out to test if plasma extravasation induced by capsaicin (90 micrograms/kg) in the bronchi of Sprague-Dawley rats could be reduced 10-30 min (0 day), 20-24 h (1 day), 3, 7 or 14 days after unilateral midcervical vagotomy. The second aim of this study was to demonstrate if substance P (3 micrograms/kg) could intensify neurogenic plasma extravasation in the bronchi in which sensory innervation was partially deprived by vagotomy. In the rats 0 days after vagotomy (0 days postvagotomy) that received capsaicin, plasma extravasation in the mainstem and secondary bronchi ipsilateral to vagotomy did not decrease. Capsaicin-evoked plasma extravasation in the secondary bronchi ipsilateral to vagotomy decreased significantly 1, 3, 7 and 14 days after vagotomy as compared with that of 0 days postvagotomy. Differences in extravasation between the secondary bronchi of the two sides were usually significant in animals 3, 7 or 14 days postvagotomy. The effect of unilateral vagotomy on plasma extravasation in the mainstem bronchi was variable. Plasma extravasation produced by substance P in the mainstem and secondary bronchi of rats 0 days postvagotomy was similar to that of unoperated rats receiving either capsaicin or substance P. Unilateral vagotomy did not decrease the amount of substance-P-induced plasma extravasation in the mainstem or secondary bronchi ipsilateral to vagotomy in rat groups 1, 3, 7 or 14 days postvagotomy as compared with that of their contralateral bronchi. This study suggests that the secondary bronchi were the chief location of the bronchial tree that could be desensitized after unilateral cervical vagotomy to stimulation by the irritant capsaicin. This desensitization developed within 1 day after vagotomy, therefore the capsaicin-evoked neurogenic inflammation in the bronchi of the vagotomized side was reduced. Exogenous substance P resulted in mucosal edema and degranulation of goblet cells in the bronchi of both vagotomized and opposite sides. The number of mediator-sensitive blood venules did not decrease following vagotomy operation. It is suggested that substance P was insufficient after vagal denervation, but substance-P receptors on the endothelial cells and goblet cells in the denervated regions were still operative.

Animals↗
PubMed1994

Ragweed antigen E and anti-IgE in human central versus peripheral isolated bronchi.

The ability of antigen to contract passively sensitized tissues was examined in human central (5 to 12 mm) and peripheral (0.5 to 2 mm) bronchi. Both central and peripheral bronchi contracted to ragweed antigen E (RW AgE), and these contractions were virtually abolished by a combination of indomethacin, cysteinyl-leukotriene, and histamine antagonists. There were, however, quantitative differences in contractile responses and in mediator release to RW AgE between central and peripheral bronchi. RW AgE was approximately 20-fold more potent in contracting peripheral bronchi compared with central bronchi. On a per weight of tissue basis, RW AgE released six-fold more histamine, 15- to 20-fold more immunoreactive leukotriene D4 (i-LTD4) and two- to 10-fold more prostanoids in the peripheral bronchi compared with central bronchi. Anti-IgE mimicked the effect of RW AgE with respect to inflammatory mediator release and with respect to the magnitude of the contractile response in peripheral and central bronchi. Anti-IgE, however, was more potent in contracting central than peripheral bronchi. Moreover, in peripheral bronchi, contractile responses to anti-IgE were only partially inhibited by a combination of indomethacin, cysteinyl-leukotriene, and histamine antagonists. These results indicate that the qualitative characteristics of antigen-induced mediator release and muscle contraction are similar in central versus peripheral bronchi. However, RW AgE is much more potent in causing smooth muscle constriction, and is capable of releasing a greater quantity of inflammatory mediators in peripheral bronchi/bronchioles than in the more central bronchi.

Adult↗
PubMed1983

Structural variation in the named bronchi of the left lung. A morphometric study.

In order to establish whether or not the named bronchi of the left lung differ structurally from each other, their proportions of cartilage, gland and muscle in normal and chronic bronchitic patients were measured. In the normal subject the lower lobe bronchus contains proportionally more muscle than either the upper lobe bronchus or the segmental bronchi. Its proportion of cartilage is less than that of the main and upper lobe bronchi, and in this respect it is similar to the segmental bronchi. The proportions of gland in the main, upper and lower lobe bronchi are the same. There is no difference between the tissue proportions of the segmental bronchi of the upper and lower lobes. In chronic bronchitics the proportion of gland is increased, and in many cases there is also an increase in muscle. The relatively high proportion of muscle in the lower lobe bronchus is no longer apparent, and its proportion of cartilage is greater than in the normal subject. The main and upper lobe bronchi contain a higher proportion of gland than the lower lobe bronchus and the segmental bronchi. The proportions of the components in the upper and lower segmental bronchi are again similar. It is concluded that in the left lung the tissue proportions of the named bronchi vary. In particular, the normal lower lobe bronchus is characterized by a relatively high percentage of muscle, and a similar cartilage content to the segmental bronchi. Care is therefore needed in selecting airways for morphometric studies.

Aged↗