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PubMed1977

Potentiation of beta-sympathomimetics with alpha-adrenoceptor blocking drugs in guinea pig trachea and human bronchus preparations.

The actions of beta-sympathomimetics alone and in various combinations with alpha-adrenoceptor blocking agents were studied in guinea pig tracheal chain and in some preparations of human bronchi taken in operations. All the alpha-adrenoceptor blockers caused 50-100% potentiation of the effects of the beta-sympathomimetics studied in both preparations, had no effects of their own in the rather low concentrations used (10(-10) --10(-6) mol/l). The results show that guinea pig and human tracheobronchial smooth muscle react similarly to these drugs and may contain adrenergic alpha-receptors.

Adrenergic alpha-Antagonists↗
PubMed1980

Papilloma of the bronchus.

Based on the observation of a recurring bronchial papilloma in a 56-year-old male, the authors aim at directing the interest of pneumologists, and especially endoscopists, to this group of rare lesions. The tumor observed obviously developed in a lung lobe affected by chronic tuberculosis, and presented with luminal obstruction. The histopathological definition of solitary papilloma, its differential diagnosis from from papillomatosis, the probable dignity of this type of lesions and the clinical features are discussed.

Bronchial Neoplasms↗
PubMed1983

[Etretinate (Ro 10-9359, Tigason) and CCNU (1-(2-chloroethyl)-3-cyclohexyl-l-nitrosourea) and bleomycin versus CCNU and bleomycin in the treatment of advanced squamous cell carcinoma of the bronchus (Working group on Internal Medicine Oncology Study BS1/78)].

Forty-six evaluable patients with advanced squamous cell carcinoma of the lung were treated in a randomized fashion with either etretinate, CCNU and bleomycin in combination (ECB) or with CCNU and bleomycin (CB). There were no complete and no partial responses. Minor responses occurred in 5 patients (24%) with ECB and in 3 patients (12%) with CB independently of histological grade. No change was observed in 9 patients (43%) with ECB and in 13 patients (52%) with CB. There was no survival difference between the two groups. Reversible side-effects of skin and mucous membranes were more frequent under ECB. The antitumor efficacy of CB is marginal and could not be improved by the addition of the vitamin-A-derivative etretinate.

Adult↗
PubMed1984

Comparative actions of biologic and synthetic leukotrienes on isolated human bronchus and rat mast cells.

The effects of biologically prepared leukotriene C4 (LTCb) and leukotriene D4 (LTDb), obtained from rat monocytes stimulated with the calcium ionophore A23187, were compared with those of chemically synthetized leukotrienes (LTCs and LTDs) using two in vitro systems. All four leukotriene preparations (10(-10) to 6 X 10(-6) M) showed equal activity upon human bronchi, inducing slow, sustained contractions. LTCb alone (10(-7) to 6.9 X 10(-7) M) elicited histamine release and enhanced compound 48/80-induced release in a dose-dependent manner from rat mast cells. In contrast, LTDb alone was without effect but inhibited release caused by 48/80. FPL 55712 failed to block the LTCb and LTDb effects on the release process. The synthetic leukotrienes neither caused histamine release nor modulated 48/80-induced release from rat mast cells. We conclude that biologic and synthetic leukotrienes exhibit comparable contractile activity on isolated human bronchi but only biologic preparations modulate histamine release by previously unappreciated substances that isolate with the biologic leukotrienes.

Animals↗
PubMedDate not supplied

Cytology of basaloid squamous carcinoma of the bronchus. A case report.

BACKGROUND: The cytologic appearance of basaloid squamous carcinoma (BSC) arising in the lower respiratory tract has not been described very well because of its rarity. This article describes a surgical case of bronchial BSC and provides the first documentation of the sputum and imprint cytologic features of the tumor. CASE: A 74-year-old man presented with hemoptysis. An abnormal intrabronchial mass was revealed by computed tomography and bronchoscopy. Preoperative cytology and biopsy showed that the mass was composed of small, round, atypical cells, but correct diagnosis was difficult. Under a tentative diagnosis of small round cell carcinoma, a right lobectomy was performed. The resected tumor was composed of small cells showing peripheral palisading and partial epidermoid differentiation. There was no glandular differentiation. Focal necrosis was also noted. Immunohistochemical markers for smooth muscle and neuroendocrine cells were negative. The tumor was eventually diagnosed as BSC or basaloid carcinoma (BC) with squamous differentiation. CONCLUSION: It is important to recognize this disease, especially when undetermined small round cell carcinoma is noted in cytologic specimens, in order to properly assess prognosis. Cytologic detection of nuclear palisading of the neoplastic cells, one of the hallmarks of the disease, may be difficult, however, careful examination to reveal neoplastic cells showing squamous differentiation appears helpful for diagnosis.

Aged↗
PubMedDate not supplied

Signet ring adenocarcinoma metastatic to the bronchus and mimicking goblet cell hyperplasia. A case report.

BACKGROUND: Goblet cells in the lower respiratory tract are metaplastic bronchial epithelial cells usually associated with asthma or chronic bronchitis. Goblet cells acquire their name by a tendency to distend with mucus, with subsequent distortion in cell shape. Due to similarity of shape, metaplastic goblet cells and signet ring cells can be easily confused in cytologic samples. CASE: A 55-year-old male with a history of gastrointestinal adenocarcinoma underwent brushing, washing and biopsy of a bronchial lesion. The bronchial wash and brush samples showed a very cellular specimen, with large aggregates of distended columnar cells. These were arranged in long strips, thick bundles and occasional three-dimensional aggregates. Some aggregates contained numerous rounded cells with markedly distended cytoplasm. The rounded cells were slightly larger than the distended columnar cells. These cells had a relatively large but innocuous-appearing nucleus displaced to the periphery of the cell. The corresponding bronchial biopsy revealed signet ring adenocarcinoma, presumably metastatic from the gastrointestinal primary. CONCLUSION: Signet ring adenocarcinoma, either primary or metastatic, can be difficult to diagnose in cytologic and histologic specimens. There are numerous mimics of signet ring cells, both benign and neoplastic. In respiratory cytologic specimens, one of the benign imposters is goblet cell metaplasia.

Bronchial Neoplasms↗
PubMed1994

Contractile effects of bradykinin on the isolated human small bronchus.

Bradykinin (Bk) induced a contraction in all small bronchi samples (diameter, 0.5 to 1 mm) from 20 patients. pD2 was 7.7 +/- 0.1 (pD2 = -log EC50) and maximal effect (Emax) was 36.2 +/- 4.7% of the maximal response to acetylcholine. The B2 agonist [Hyp3TyrMe8]Bk contracted airway smooth muscle with a pD2 of 7.8 +/- 0.2 and an Emax of 39 +/- 9%. The B1 agonist [Sar1dPhe8desArg9]Bk induced only a weak contraction at 10(-6) M. The effect of Bk was abolished by the B2 (Hoe 140) but not by the B1 [Leu8desArg9]Bk receptor antagonist. Indomethacin 10(-6) M abolished Bk-induced contraction, suggesting that cyclooxygenase products are involved in Bk action. Capsaicin 10(-5) M, which selectively depletes C fibers from airway mediators through the ruthenium red pathway, and ruthenium red 10(-5) M significantly inhibited the concentration-response curves to Bk. However, tetrodotoxin (+/-)-CP-96,345, SR 48968, and atropine did not significantly affect Bk concentration-response curves, suggesting that nerve conduction, substance P (SP), neurokinin A (NKA), and acetylcholine release are not involved in Bk action. Our data indicate that Bk contracts human distal airway smooth muscle through the Bk B2 receptor and a cyclooxygenase pathway. This effect appears to involve capsaicin and ruthenium red pathways but neither acetylcholine nor NKA and SP release.

Acetylcholine↗
PubMed1994

Potentiation of nonadrenergic noncholinergic relaxation of human isolated bronchus by selective inhibitors of phosphodiesterase isozymes.

Human bronchial rings were contracted with histamine (3 microM), and inhibitory responses were obtained with electrical field stimulation (EFS) in the presence of propranolol (1 microM), atropine (1 microM), and indomethacin (3 microM). These nonadrenergic noncholinergic (NANC) relaxations were frequency-dependent (1 to 32 Hz) and inhibited by either tetrodotoxin or Nw-nitro-L-arginine (L-NNA, 100 microM). The selective cAMP-specific phosphodiesterase (PDE) type IV inhibitors rolipram (3 microM) and Ro 20-1724 (3 microM) significantly potentiated NANC relaxations at each frequency of stimulation. The selective cGMP-specific PDE type V inhibitor zaprinast (3 microM) failed to significantly alter the maximal NANC response, but it caused a slight potentiation of the response at lower frequencies. The adenylyl cyclase stimulant forskolin, the nitric oxide donor compound 3-morpholinosydnonimine (SIN-1), and the guanylyl cyclase stimulant sodium nitroprusside caused concentration-dependent relaxation of histamine-contracted airway smooth muscle. Rolipram significantly potentiated the relaxation elicited by forskolin. Rolipram also potentiated responses to SIN-1 and sodium nitroprusside. Considered together these data support the hypothesis that cAMP plays a facilitory role in NANC relaxation of the human bronchi.

Atropine↗
PubMed1998

Mechanisms of immune sensitization of human bronchus.

Bronchial hyperresponsiveness (BHR), the increased sensitivity to a wide variety of stimuli that narrow the airways, is a central abnormality in patients with asthma, and is frequently observed in patients with chronic obstructive pulmonary disease. In the study of the underlying mechanisms of BHR, various animal models have been employed, using methods of active and passive immunization. These studies have led to a changed understanding of smooth muscle hyperreactivity, questioning both the past paradigm of altered neural activity and the modern concepts of inflammation as the single most factor determining BHR, and emphasizing the particular importance of the end organ- the smooth muscle cell. More recently, passive sensitization of human airways has been used by several investigators to describe the mechanisms of allergic sensitization and to study the role of functional abnormalities of human airway smooth muscle, which may represent the key to understanding human BHR, and thus lead to novel treatment approaches for the future.

Animals↗
PubMed1987

The effect of indomethacin on immunologic release of histamine and sulfidopeptide leukotrienes from human bronchus and lung parenchyma.

We studied the effect of indomethacin on immunologic mediator release from human bronchial tissue (n = 6) and lung parenchyma (n = 7). Tissues were obtained from surgical specimens, minced, passively sensitized, and challenged with antigen E or anti-IgE in the presence or absence of indomethacin. At maximal levels of immunologic stimulation with either antigen or anti-IgE, the bronchial and parenchymal tissues released approximately 5 and 20% of total histamine (net), respectively, and approximately 3.5 and 45 ng/g of immunoreactive sulfidopeptide leukotriene, respectively. Analysis by high performance liquid chromatography followed by radioimmunoassay revealed that the airway supernatants contained LTD4 and LTE4, whereas the lung parenchymal samples contained predominantly LTE4. Little or no LTC4 was detected in either airway or parenchymal samples. Incubation with indomethacin (5 x 10(-6) M) resulted in approximately a 3-fold increase in antigen or anti-IgE-induced release of leukotrienes from the bronchial tissue. Indomethacin also enhanced antigen-induced histamine release approximately 2-fold but had no effect on anti-IgE-induced histamine release from this tissue. In contrast, indomethacin had no effect on antigen or anti-IgE-induced histamine or leukotriene release from the lung parenchymal tissue at any level of immunologic stimulation. These results support the hypothesis that indomethacin enhances human anaphylactic bronchospasm in vitro through an increase in mediator release from bronchial mast cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies, Anti-Idiotypic↗
PubMed1991

Abnormalities in airway smooth muscle in fatal asthma. A comparison between trachea and bronchus.

Tracheal smooth muscle from seven cases of fatal asthma demonstrated an increased contractile response to histamine, acetylcholine, and electrical stimulation of intrinsic cholinergic nerves; impaired relaxation to isoproterenol, and possibly theophylline, was also evident (1). Fourth generation bronchial spirals from the same patients were also studied, and these results were compared with those of the trachea and normal bronchi (n = 5). In contrast to trachea, contractile responses in asthmatic bronchi to acetylcholine, histamine, and cholinergic nerve stimulation were similar to those in control bronchi. The potency of isoprenaline (IC50) was reduced 9.4-fold (p less than 0.003), similar to trachea (4.5-fold), whereas theophylline responses were normal. The discrepant results obtained may reflect differences in the disease process, including rates of postmortem change, at the two anatomic sites.

Acetylcholine↗
PubMed1991

Columnar papilloma of the bronchus. Case report and literature review.

Solitary papillomas are rare endobronchial neoplasms that are most commonly lined by a squamous epithelium (i.e., squamous papillomas). Papillomas exhibiting nonsquamous epithelium are even more unusual; only seven solitary papillomas lined by columnar epithelium (i.e., columnar papillomas) have been previously described. The current report presents the eighth patient with a columnar papilloma and demonstrates some features common to solitary papillomas (i.e., central location in the airways, associated atelectasis), but distinctive from squamous papillomas (i.e., absence of malignant potential).

Aged↗