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A new method for selective left main bronchus intubation in premature infants.

Unilateral massive pulmonary atelectasis, and pulmonary interstitial emphysema (PIE) are problems that frequently occur in ventilated premature infants. Selective main bronchus intubation (SBI) of the atelectatic lung, or the contralateral lung in unilateral PIE, is an accepted procedure. However, whereas right SBI is usually easily performed, left SBI is frequently difficult. We have developed a method for left SBI using a regular portex endotracheal tube in which an elliptical hole 1 cm in length has been cut through half the circumference 0.5 cm above the tip of the oblique distal end. With the elliptical side hole directed to the left lung, left SBI can easily, and repeatedly be accomplished. This method may prove life saving in certain cases of unilateral atelectasis or PIE.

Bronchi↗

A technique for study of lung function in birds by blocking the primary bronchus.

The technique described allows in vivo placement of a blocking balloon in the avian primary bronchus between the origins of the two sets of secondary bronchi, the medioventrals and mediodorsals. With caudal air sacs cannulated the animal may then be ventilated with a constant flow of gas passing entirely through the gas-exchanging parabronchi. This technique has been found useful particularly in studies of pulmonary gas exchange in birds.

Animals↗

Interaction between fenoterol, ipratropium, and acetylcholine on human isolated bronchus.

Functional antagonism between fenoterol (F) and acetylcholine (ACh) and interaction between F and ipratropium (Ipr) on ACh-induced contraction were evaluated on isolated human bronchi. In the presence of increasing concentrations of ACh (2 X 10(-4) and 2 X 10(-3) mol/L), dose-response curves of the relaxant effect of F were shifted to the right (0.45 and 0.92 log units), and the maximal effect of F, expressed as a percentage of the effect of theophylline, 3 X 10(-3) mol/L, was reduced from control values of 92.1 +/- 4% to 70.8 +/- 7.0%, and to 67.2 +/- 7.1%, according to the functional antagonism. In the presence of Ipr, 10(-9) and 10(-8) mol/L, the functional antagonism between ACh and F was partially reversed. Concentration response-curves to F versus ACh, 2 X 10(-3) mol/L, were shifted to the left, and although the -log molar concentration producing 50% of maximal effect was not significantly modified, the maximal effect of F was significantly increased in the presence of Ipr, 10(-8) mol/L. It is concluded that the effect of combined F and Ipr on the isolated human bronchus contracted with ACh appears to be of the additive type.

Acetylcholine↗

Further evidence that tachykinin-induced contraction of human isolated bronchus is mediated only by NK2-receptors.

The tachykinin-receptors mediating contraction of human bronchus have been characterized using both tachykinin-receptor selective agonists and blocking drugs under conditions where tachykinin metabolism by endogenous peptidases has been controlled, and true equilibrium conditions have been established. The findings that neurokinin A (EC50 = 2 nM) is the most potent agonist, and the NK2-receptor selective agonist, GR64349, is only 3-fold weaker, whereas agonists selective for NK1-receptors, substance P methyl ester, or NK3-receptors, senktide, are inactive, suggest that this effect is mediated exclusively by NK2-receptors. This is supported by observations that GR64349 is antagonised by the selective NK2-receptor blocking drugs, MEN10207 (pA2 = 6.7), R396 (pA2 = 6.1), (+/-)SR48968 (pA2 = 8.4) and GR159897 (pA2 = 8.6), but not by the NK1-receptor blocking drug, GR82334 (pA2 < 5). In approximately half of the preparations, the peptidase inhibitors, phosphoramidon (1 microM) and bestatin (100 microM), caused a marked and well-maintained contraction (approximately 20% of neurokinin A maximum), which may indicate a role for endogenous tachykinins in the regulation of tone in this preparation. This is supported by the finding that neurokinin A-immunoreactive nerve fibres are located around intrinsic neurones of local ganglia and within the smooth muscle layer of this preparation.

Aged↗

Accessory cardiac bronchus: demonstration by computed tomography.

Distinctive computed tomography features of the accessory cardiac bronchus are illustrated. Bronchial anomalies, while rare, are important to recognize, especially if bronchoscopy or surgery is anticipated. Related clinical symptoms are thought to be secondary to retained secretions.

Adenocarcinoma↗

Uptake of ferritin and Bordetella avium in bronchus-associated lymphoid tissue of turkeys.

The uptake of macromolecular and particulate materials in bronchus-associated lymphoid tissue (BALT) in turkeys was examined using transmission electron microscopy. Tracer materials used were live and ultraviolet-killed (UV-killed) Bordetella avium and ferritin. Suspensions of bacteria and ferritin were instilled via intratracheal catheterization and allowed to remain in contact with the respiratory surfaces for 0, 10, 30, 60, 90, and 120 min. Ferritin and B. avium were taken up by both ciliated and non-ciliated cells of the epithelium overlying BALT (BALT epithelium). Ferritin was found in organelles associated with endocytosis (i.e. apical vesicles, endosomes, cytoplasmic vacuoles) and was apparently transported across epithelial cells, since it was also found in intercellular spaces. Bacteria were found in vacuoles within BALT epithelial cells, but not free in intercellular spaces. Some macrophages in BALT epithelium also contained bacteria. No differences were observed between uptake of live and UV-killed bacteria. We conclude that both ciliated and non-ciliated cells of BALT epithelium in turkeys are able to take up macromolecular and particulate materials. Bacteria are also accessible to intraepithelial macrophages, although whether they are taken up directly from the bronchial surface or whether they pass through epithelial cells first could not be determined. This evidence suggests that antigens, including respiratory pathogens, could gain access to cells of the avian immune system by transepithelial passage in BALT.

Animals↗

Massive haemoptysis death and other morbidity associated with high dose rate intraluminal radiotherapy for carcinoma of the bronchus.

Four hundred and six patients with primary non-small cell carcinoma of the bronchus causing symptoms due to endobronchial disease, were treated with intraluminal radiotherapy (ILT) using the microSelectron-HDR machine at the Christie Hospital, Manchester, between April 1988 and the end of 1992. An assessment of morbidity for this treatment is presented, particularly with regard to the risk factors and causes of massive haemoptysis death. The most common early side-effect was a mild transient exacerbation of cough which usually resolved within 2-3 weeks. At various times following ILT treatment 83 bronchoscopies were carried out randomly in 55 patients. In bronchoscopies carried out within the first 3 months following ILT, no tumour was visible in 80% of cases. A mucosal radiation reaction score (RRS) was used to grade bronchoscopic appearance after ILT treatment. Overall, 55% of bronchoscopic examinations showed some degree of mucosal radiation reaction. The majority of radiation reactions from 6 months onwards after ILT demonstrated a degree of fibrosis. A radiation reaction was seen more frequently after treatment with 2000 cGy as opposed to 1500 cGy at 1 cm from the central axis of the radiation source. Thirty-two patients were identified who had died from massive haemoptysis (MH) as a terminal event. A Cox multivariate regression analysis showed that the treatment-related factors of increased dose at first ILT (P = 0.004), prior laser treatment at the site of ILT (P = 0.020) and second ILT treatment in the same location as the first ILT treatment (P = 0.047), all significantly increased the relative risk of MH death compared with their effect on the relative risk of death from other causes (OC). (In addition a fourth treatment-related factor, namely the concurrent use of ILT and external beam radiotherapy (EB) had a P value of 0.08). Twenty out of 25 assessable MH-death patients (80%) had evidence of recurrent or residual tumour before death but 5 patients (20%) did not. For surviving patients the instantancious risk of death at any one time (the cause-specific death rate expressed as deaths per 100 cases per month), showed a sharp peak for MH deaths between 9 and 12 months post ILT in contradistinction to OC death where the peak was between 3 and 6 months post ILT. These findings may imply a role for late radiation reaction in the treatment-related risk factors identified as increasing the relative risk of MH death and possible mechanisms are discussed. The results have implications for treatment regimes that use a dose of 2000 cGy at 1 cm in a single fraction technique, that have a high frequency of previous laser treatment, that use multiple, repeated ILT treatments in the same location and that use ILT concurrently with EB.

Aged↗

Bronchiolo-alveolar regions in adenocarcinoma arising from canine segmental bronchus.

Adenocarcinomas induced in canine bronchial segments placed subcutaneously have bronchiolo-alveolar regions. Immunocytochemistry and routine staining of adjacent sections strongly suggests that the lining of these regions consists of type II cells. These regions may thus represent true prospective alveolar regions, as also seen in embryonic lungs. This first observation of bronchoalveolar cancer arising from a major bronchus indicates that the carcinogen-induced neoplastic progression in bronchial epithelium may lead to type II cell differentiation and type II cell tumor development. The preservation of cell properties in serial nude mouse transplants suggests that it is a stable type II cell population.

Adenocarcinoma↗

Effects of ageing on nicotine-induced contraction and substance P-like materials release in guinea-pig bronchus.

1. Effects of ageing on nicotine-induced contraction and release of substance P-like materials in the bronchial preparations from guinea-pigs of different ages were studied. 2. The pD2 value (potency) of nicotine decreased with age from 10 to 100 weeks. The pD2 value of substance P did not change with age suggesting that substance P receptor mechanisms do not alter with age. 3. The amount of substance P-like materials released by nicotine (10(-4) M) decreased with age from 10 to 100 weeks, supporting our previous findings that nicotine contracts the guinea-pig bronchus through the release of substance P-like materials. 4. These results suggest that the age-related decrease in the pD2 value (potency) of nicotine is due to the reduction in the amount of substance P-like materials released by nicotine.

Aging↗

Primary tumor control after radiotherapy for carcinoma of the bronchus.

The primary tumor control and the appearance of distant metastasis was observed closely in 62 patients entered into a randomized controlled trial of the radiosensitizing drug, misonidazole, in carcinoma of the bronchus. Sixty-one of the 62 patients are now dead; an autopsy examination was carried out in 42 (69%). Although survival was comparable to that observed in similar studies, tumor persisted or recurred at the primary site in 95% (58/61) while 39% (24/61) showed no evidence for distant metastasis. In these patients, improvement in the primary tumor control would be important in extending survival.

Bronchial Neoplasms↗

The relationship between tumor response and survival following radiotherapy for carcinoma of the bronchus.

Tumor response was closely observed in a randomized controlled trial of a radiosensitizing drug in the radiotherapy of carcinoma of the bronchus. The persistence of tumor cells in the sputum after treatment and the degree of regression measured radiologically at two months did not correlate with the subsequent course. However, total regression of tumor and time to regrowth both assessed radiologically showed a highly significant correlation with survival (P less than 0.0005).

Bronchial Neoplasms↗

Evaluation of short-course preoperative irradiation in the treatment of resectable bronchus carcinoma: long-term analysis of a randomized pilot-study.

A randomized pilot-study on patients with resectable non small-cell lung carcinoma was conducted from December 1971 to May 1976 inclusive. Patients were randomly assigned to receive preoperative irradiation to the mediastinum followed by surgery (RT + S), or to be treated by surgery only (SO). A total of 33 patients clinically staged as T1-2, N0, M0 histologically confirmed bronchus carcinoma were entered onto the study. Sixteen patients were assigned to RT + S and 17 patients received SO. There were 3 operative mortalities, all of them in the SO group. A total of 28 patients, 14 in each group are evaluable, with a minimum period of observation of 7 years. Preoperative irradiation consisted of a Telecobalt photon-beam applied to the mediastinum as anterior and posterior portals. The thoracic spine was protected on the posterior portal by a narrow lead block. A total dose of 20 Gy calculated in the mid plane was given in 5 equal fractions each of 4 Gy administered on 5 consecutive days: Monday through Friday; patients were operated on the following Monday after the week-end. Surgical treatment was similar for both groups and consisted of lobectomy or pneumonectomy, depending on the size and site of the primary tumor. Analysis of the survival data showed an absolute crude 5 years survival rate of 58% for patients who received RT + S versus 43% for SO. The corrected actuarial 5 and 10 years survival rates are 78 and 69% for the group that received RT + S, and 67 and 55% for the group treated by SO, respectively. Nineteen patients were treated more than 10 years ago. Four of 8 (50%) treated by RT + S are alive with no evidence of disease (NED), and 3/11 (28%) treated by SO are alive with NED. The median survival period for the group that received RT + S is 72 months versus 30 months for the group treated by SO. Analysis of the adequacy of surgical resection based on histological examination of the operative specimen showed higher incidence of radical resection in the group that received RT + S (57 versus 28.5%). It is concluded that the treatment protocol of preoperative radiation therapy as outlined is well tolerated and the results are encouraging.

Aged↗

Continuous, hyperfractionated, accelerated radiotherapy (CHART) in non-small cell carcinoma of the bronchus.

Between January 1985 and December 1988, 62 patients with locally advanced carcinoma of the bronchus were treated by radiotherapy using continuous, hyperfractionated, accelerated radiotherapy (CHART). With this regime on each of 12 consecutive days 3 fractions were given with a time interval of 6 hr between each. Initially a dose fraction of 1.4 Gy was used and a total of 50.4 Gy was achieved in 23 patients. As tolerance was good, the dose increment was raised to 1.5 Gy and the total to 54 Gy in the subsequent 39 patients. Esophagitis was the only immediate complication, and although most patients were reduced to a fluid diet for a period, recovery was complete and only one patient required endo-esophageal tube feeding for a short time. The results observed so far have been assessed against those in a previous trial of a radiosensitizer in cases similarly accepted for treatment. Complete regression, as observed radiologically, was achieved by 42%; this can be compared with 15% of the previously treated series. At 1 year the survival probability was 64% compared with a previous 44% and at 2 years 34% compared with a previous 12%. A randomized controlled clinical trial is now planned.

Carcinoma, Bronchogenic↗

Traumatic rupture of right mainstem bronchus in a child.

We report a case of a 7-year-old boy who sustained a ruptured right mainstem bronchus in a motor vehicle accident. The clinical presentation, pathophysiology, and diagnosis of tracheobronchial injuries secondary to nonpenetrating thoracic trauma are discussed.

Accidents, Traffic↗

Characterization of nicotine-induced contraction in the canine bronchus.

1. The modes of action of nicotine on the dog bronchial smooth muscle preparation was investigated, in order to compare with those on the bronchial preparations from the guinea-pig, rabbit and monkey. 2. Nicotine induced a contraction in the dog bronchial preparation, and this response was abolished by hexamethonium and atropine and potentiated by physostigmine. 3. These findings suggest that the contractile response to nicotine was mediated through an action on the nicotinic receptors and due to the release of acetylcholine. 4. Tetrodotoxin did not inhibit the contractile response to nicotine in the dog bronchial preparation, suggesting that the nicotine-induced response may be produced mainly through a sodium action potential-independent process. 5. The present observations in the dog bronchial preparations coincided with those in the rabbit and monkey bronchi but not with the findings in the guinea-pig bronchus.

Animals↗

The neuroimmune link in the bronchus-associated lymphoid tissue (BALT) of cat and rat: peptides and neural markers.

This light microscopic immunohistochemical study investigates the distribution and target interrelations of nerve fibers in bronchus-associated lymphoid tissues (BALT) of rat and cat by using antisera against (1) the polyneuronal marker protein gene product 9.5 (PGP 9.5), (2) selected opioid and nonopioid peptides, and (3) the marker enzymes tyrosine hydroxylase (TH) and dopamine beta-hydroxylase (DBH). In both species, a similar distribution pattern of PGP, peptide, and catecholamine enzyme immunoreactive was observed. Anti-PGP 9.5 stained all nerve fibers (except some smaller, calcitonin gene-related peptide-immunoreactive (CGRP-ir) fibers presumably of the C-type) throughout the different compartments of BALT, e.g., under the epithelium, in the smooth muscle layer, along the vasculature, and between immune cells of BALT parenchyma. The distribution of fibers staining for peptides (substance P (SP), (CGRP), neuropeptide Y (NPY). Leu-enkephalin, Met-enkephalin-Arg-Gly-Leu) and/or the catecholamine enzymes was also not compartment-specific. However, the density of the different peptidergic fibers and those staining for the marker enzymes exhibited region- and target-specific variations, e.g., fibers, cocontaining substance P and CGRP were more ubiquitous in nonvascular regions than codistributed NPY-, TH-, and DBH-ir fibers, which clearly prevailed in perivascular plexus. Regularly, nerve fibers staining for any of the peptides and markers investigated formed close contacts with mast cells, cells of the macrophage/monocyte cell line (identified as ED1 + cells), and/or other lymphoid cells, although with different frequencies. We assume that the SP/CGRP innervation is mainly of primary sensory origin, while the NPY innervation is chiefly derived from postganglionic noradrenergic sympathetic neurons. The VIP/PHI component is most likely postganglionic cholinergic while the opioid component, apparently derived from the Proenkephalin precursor, could be of differential origin. We propose that the neuroimmune connections in BALT play a significant role in the regulation and/or modulation of physiological/pathophysiological mechanisms of the lung. BALT may also be an integral part of the psycho-neuro-immune axis.

Amino Acid Sequence↗

Effect of atrial natriuretic peptide and on atriopeptins on the human isolated bronchus. Comparison with the reactivity of the guinea-pig isolated trachea.

ANF, ANF7-28 and atriopeptins (AP1, AP2 and AP3) (10(-11) to 3 x 10(-7) M) induce a relaxant response on the guinea-pig isolated trachea, which is partially potentiated by the enkephalinase inhibitor thiorphan 10(-5) M but is unmodified by epithelium removal. Conversely, these drugs were found to be without any significant relaxant effect on the isolated human bronchus. Several hypotheses, such as the activation of ANF receptors not located on airway smooth muscle or an indirect effect of ANF in vivo are suggested to explain the discrepancy between these in vitro results and those of clinical trials in asthmatic subjects.

Amino Acid Sequence↗

Stenosis of left mainstem bronchus in a case of cicatricial pemphigoid.

A case of a 22-year-old male with cicatricial pemphigoid and involvement of the bronchial system is reported. Manifestations of cicatricial pemphigoid in the mucous membranes of the airway distal to the larynx have not been hitherto described. The patient developed severe stenosis of the left mainstem bronchus 2 years after onset of the disease. Successful treatment by sleeve resection and end-to-end anastomosis was achieved. Diagnostic bronchoscopy in patients with severe dyspnoea suffering from cicatricial pemphigoid is recommended. Operative treatment of airway stenoses distal to the larynx caused by cicatritial pemphigoid is feasible.

Adult↗