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At least 433 records · Page 24Linked to original sources
PubMed1983

"Low grade" mucoepidermoid carcinoma of the bronchus with "high grade" biological behavior.

A case of mucoepidermoid carcinoma of the bronchus with low grade histologic features exhibited an aggressive biological behavior. All gross, microscopic, and ultrastructural features were those of a morphologically low grade mucoepidermoid carcinoma. Grossly, the lesion was an exophytic endobronchial mass; microscopically, it contained sheets of monomorphic cells with well-formed mucus glands, no mitoses, and no necrosis; and ultrastructurally, it consisted of numerous goblet cells and mitochondria- and glycogen-rich cells with well-formed microvilli. However, the patient developed widespread metastases to skin, subcutaneous tissue, femur, vertebral column, and pericardium and died two months after the primary endobronchial tumor was excised. The metastases, like the primary tumor, had the appearance of "low grade" mucoepidermoid carcinoma. Explants of the original tumor grown in nude mice for three months showed persistence of the low-grade morphologic pattern. Although metastases are known to occur frequently from high-grade lesions, widespread metastases from histologically low-grade lesions have not previously been reported. Low-grade histologic features of mucoepidermoid carcinoma are not necessarily then indicative of low-grade biological behavior.

Adult↗
PubMed1984

Mucoepidermoid carcinoma of the bronchus in a 4-year-old child. A high-grade variant with lymph node metastasis.

A high-grade mucoepidermoid carcinoma with lymph node metastasis occurred in the bronchus of a 4-year-old child. The tumor was pedunculated, obstructive, and invasive. Squamous and glandular elements were seen on light and electron microscopic examination. This is a very rare tumor in the pediatric age group. This is the first instance of this lesion associated with metastasis.

Bronchial Neoplasms↗
PubMed1987

Retrospective and prospective tumor staging evaluating prognostic factors in operated bronchus carcinoma patients.

Survival, pTN stages, and cell type of patients operated on for bronchus carcinoma were evaluated in a retrospective study and compared with data obtained in a prospective study. One thousand three hundred thirty-two patients with potential curative resected lung carcinoma were included in the retrospective study. Two hundred eighty-two patients with potential curative resected lung carcinoma were analyzed in the prospective study. Data showed similarities in distribution of cell type and relative frequency of pT1 stage in both collectives. Major differences between both studies were obtained in relative frequencies of pT3, and pN0, pN1, and pN2 stages. Survival of patients grouped according to cell type revealed differences between patients suffering from epidermoid-adeno carcinoma and patients suffering from small anaplastic carcinoma--large cell anaplastic carcinoma in both studies. Patients stated as pN0 stages showed more favourable prognosis in the prospective study compared with patients of the retrospective study. Two-year survival rates of patients grouped into a pT1pN0 stage and into a pT2pN0 stage had similar survival rates in both studies. Survival of these cohorts compared with patients staged as pT1pN1 and pT2pN1 was statistically significantly better. The data indicate that patients suffering from pT1pN1 or pT2pN1 tumors should be classified as Stage II tumors.

Age Factors↗
PubMed1984

Gut- and bronchus-associated lymphoid tissue.

Bronchus-associated and gut-associated lymphoid tissues (BALT and GALT) have both functional and morphologic similarities and are involved in seeding lung, gut, and other mucosal sites with predominantly IgA-containing B cells. Both types of lymphoid tissue are engaged in the regulation and the controlled amplification of immune responses, which vary from positive mucosal responses in both mucosae and peripheral tissues to local mucosal responses and systemic tolerance. Their further involvement in provision of cells destined to reside in the epithelial compartment of the body appears likely but requires further investigation. Their role in the provision of precursors of mucosal mast cells must also be explored further, but some participation in this event appears likely. The mucosa-associated lymphoid tissue (MALT) system appears to be integrated with the systemic immune system but may be considered as separate from it in several functional ways.

Animals↗
PubMed1989

Lymphocyte subpopulations in high endothelial venules and lymphatic capillaries of bronchus-associated lymphoid tissue (BALT) in the rat.

The subpopulations of lymphocytes and non-lymphoid cells in high endothelial venules (HEV) and in lymphatic capillaries surrounding lymphoid follicles in bronchus-associated lymphoid tissue (BALT) were examined by electron microscopy after preembedding the tissue and staining with an immunoperoxidase technique. The results were compared with those obtained in gut-associated lymphoid tissue (GALT) reported previously. Monoclonal mouse-anti-rat T cell, IgG, IgM, IgA, and Ia antisera were used. Plasma cells that were reactive to anti-IgG, anti-IgM, and anti-IgA were detected as cells in which the 3',3'-diaminobenzidine tetrahydroxychloride reaction product was localized in rough endoplasmic reticulum and perinuclear spaces but not on plasma membranes. These plasma cells did not occur in either lymphatic capillaries or HEV in BALT as they did in GALT. Cells with surface Ig (sIg cells), T-cell antigen (T cells), and Ia antigen (Ia cells) were present in BALT. T cells were located predominantly in the follicular area opposite the bronchial epithelium; IgM- and IgG-reactive cells were found in the follicular area adjacent to the bronchial epithelium; and IgA-positive cells were found in the lateral part of the area where the T cells were localized (T-cell area). Ia cells were abundant throughout BALT and in moderate numbers in the epithelium. A striking observation was the presence of "nurse-cell"-like structures in the periphery of BALT. The percentages of T, sIgG, sIgM, and sIgA cells in the HEV were 54.7%, 2.4%, 28.9%, and 27.3%, respectively, and in the lymphatic capillaries, 41.2%, 3.8%, 38.2%, and 21.2%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2004

Bronchus-associated lymphoid tissue lymphoma arising in a patient with bronchiectasis and chronic Mycobacterium avium infection.

We describe a 67-year-old woman with bronchiectasis and Mycobacterium avium complex infection who underwent wedge resection of her pulmonary infiltrates because they were progressing despite antibiotic therapy. In addition to the expected granulomatous changes, she was found to have a B-cell lymphoma of bronchus associated lymphoid tissue (BALT). Despite normal bone marrow morphology, marrow involvement was demonstrated by flow cytometry. Her lymphoma remains suppressed with antimycobacterial therapy 6 months after resection of bulk disease.

Aged↗
PubMed1985

Three-dimensional reconstruction of a small-granule paracrine cell cluster in an adult hamster bronchus.

Amine precursor uptake and decarboxylation (APUD) small-granule cells were stained by periodic acid-Schiff (PAS)-lead hematoxylin in 0.5-micron etched Epon sections of adult hamster lung fixed for transmission electron microscopy. The leading edge of a small-granule cell cluster was identified in a segmental bronchus as a single PAS-positive cell. From 256 serial thin sections through its entirety, a three-dimensional wooden reconstruction of the cluster and morphometric estimates of the apical and basal surfaces, cell volume, and intracytoplasmic distribution of mitochondria and small granules was made. Of moderate size, the body consisted of 16 small-granule cells, 11 forming its ovoid core with five outlying cells diverging at the margin; these were pyramidal, possessing wide bases and thin apical processes. At the bronchial surface, processes from the 11-cell core emerged together, whereas the divergent cells emerged in groups of two and three. Ten Clara-like cells and one ciliated cell encircled the core. Altogether they formed a pseudostratified epithelium in contrast to the surrounding simple columnar epithelium. Deeper in the cluster, numerous cytoplasmic extensions interdigitated with those from adjacent cells, and toward the base the Clara-like and APUD cells were increasingly interposed. In marked contrast to the apical cytoplasm, the infranuclear cytoplasm of the latter was densely packed with ca. 1,000 A electron-dense granules; and the basal, presumptively secretory face of each cell was five to six times greater than the area exposed to the bronchial lumen. Judged by granule size and ultrastructure, only one APUD cell type was recognized in the reconstructed cluster. Beneath it many fibrocytic processes were separated from the APUD cells by only the thickness of the basal lamina. Two fascicles of smooth muscle approached the cluster within 0.4-0.8 micron. Unmyelinated nerve fibers came as close but contacted only the muscle. Capillaries, in contrast, came no closer than 15 micron from the base of the body. Evidently, 1) fibrocytes and smooth muscle are more likely targets for secretions from such a paracrine body than cells reached through the blood-stream, and 2) not all small-granule cell clusters are innervated.

APUD Cells↗
PubMedDate not supplied

Chemiluminescence of bronchoalveolar lavage cells as an indicator of leukocyte activation in rats with a hyperreactive bronchus.

Activation and generation of inflammatory mediators by different leukocytes may be important in the pathogenesis of airway hyperreactivity. We studied the effect of active sensitization with ovalbumin as antigen and i.v. treatment with Sephadex particles on bronchial reactivity (BR) in rats and its possible relation to leukocyte infiltration (LI) and activation (LA) in bronchoalveolar lavage (BAL). A marked BR to aerosols of serotonin (5-HT) and ovalbumin was found in Sephadex treated animals but not in control animals. In parallel to this a marked increase in BAL cell count from Sephadex-treated animals compared to controls was seen. This increase in BAL cell count corresponded with a clear augmentation of spontaneous, buffer-induced and C3Z-induced, luminol-amplified CL. We deduce that detection of CL of BAL cells from rats might be used for studying inflammatory mechanisms which lead to a hyperreactive bronchus.

Animals↗
PubMedDate not supplied

Bone marrow examination in small cell carcinoma of the bronchus: an unnecessary procedure?

One hundred and thirty-seven patients with small cell carcinoma of the bronchus underwent bone marrow trephine and/or aspirate examination as part of their clinical staging. Twenty-four patients (17.5 per cent) were found to have malignant marrow infiltration. In no case was this an isolated finding of metastatic disease, indeed most patients had gross metastatic spread to liver and/or bone. Marrow infiltration has not been shown to be a major prognostic factor in response to chemotherapy or survival in previous studies. We recommend that this staging procedure be discontinued in routine clinical practice, and instead be confined to specific indications in clinical trials.

Bone Marrow Examination↗
PubMed1992

An aerodynamic valve in the avian primary bronchus.

The segmentum accelerans in geese is a constriction in the caudal end of the primary bronchus. Experimental evidence suggests that this part of the airway functions as an inspiratory aerodynamic valve, accelerating the incoming airstream past the ventrobronchial openings. The luminal diameter of the segmentum accelerans dilates in the presence of elevated CO2 levels, probably through relaxation of smooth muscle. Physiological control of the segmentum accelerans may permit inspiratory aerodynamic valving to be maintained throughout a wide range of ventilatory flows.

Animals↗
PubMed1979

Carcinoma of the bronchus with atypical presentation: report of a case.

A 64-year-old man presented with dysphagia due to obstruction of lower third of the esophagus. Esophagoscopy showed narrowing of the esophagus with normal mucosa. Chest X rays were normal, but on lung scan there was no perfusion of the left lung. That patient died of aspiration and on post mortem a carcinoma of the bronchus with abscess formation and perforation into the esophagus was found.

Bronchial Neoplasms↗
PubMed1987

Survival of operated bronchus carcinoma patients: a prospective study.

Maximum diameter, tumour volume, and inflammatory response of host tissue in 282 surgical specimens with primary carcinoma of the bronchus were measured. Cell type, pT- and pN-stage, maximum diameter and volume of the primaries, and inflammatory response of host tissue were analyzed in respect to survival of the patients. Date of death was evaluated by quarterly communications with the house physicians. Survival rates were computed by use of Kaplan-Meier estimation. Mean survival of all patients was calculated at 480 days. Lymph node involvement and tumour volume were found to have a major influence on survival. In accordance with the weak contribution of maximum diameter of the tumour to survival, no major differences in survival between pT1- and pT2-stage were found. If severe inflammatory response at the tumour boundary was noted, patients showed slightly increased survival in all tumour stages. Cell type and tumour grading were found to be of minor influence in respect to survival.

Aged↗
PubMed1988

Biochemical and ultrastructural differences between muco-epidermoid and carcinoid tumors of the bronchus.

Bronchial adenomas have been classified into three types: carcinoid tumors, cylindromas (adenoid cystic carcinomas), and mucoepidermoid tumors. Studies from our laboratory have demonstrated that the quantitative measurement of monoamine oxidase (MAO) in homogenates of carcinoid tumors of foregut origin is different than the activity enzymes in other tumors of neural crest origin. In this study we compared the biochemical composition of 12 bronchial carcinoid tumors with the biochemical composition of a rare mucoepidermoid adenoma of the bronchus. Electron microscopy revealed that some cells of the mucoepidermoid adenoma contained mucin and tonofilaments; none of the cells contained neurosecretory granules. The MAO activity of the bronchial carcinoid tumors was much higher than the MAO activity of the mucoepidermoid adenoma. Thus, there are distinctive ultrastructural and biochemical differences in these two types of bronchial adenomas.

Adenoma↗
PubMed1993

Bronchus-associated lymphoid tissue (BALT) in human fetal and infant lung.

Bronchus-associated lymphoid tissue (BALT) has been defined as the organized lymphoid tissue of the lung. Although well described in a variety of animal species, documentation of its presence and development in human lung is limited. Because the tissue to volume ratio in adult lungs is so low, a systematic search for BALT would involve so many sections as to be impractical. In this study, therefore, we have studied post-mortem specimens of fetal (n = 102) and infant (n = 17) lungs, which have a much higher tissue to volume ratio. Fetal death was due to various causes but all but two infants died from sudden infant death syndrome. In the fetal lungs, the presence of BALT was almost invariably associated with chorioamnionitis or intrauterine pneumonia, being present in 24 of 51 of these cases (47 per cent). The earliest ill-defined lymphoid aggregate was seen at 16 weeks' gestation, while lymphoepithelium, a hallmark of mucosa-associated lymphoid tissue, could be identified at 20 weeks. In 51 fetuses without infection, BALT was found in only five cases (10 per cent). BALT was identified in 13/17 (77 per cent) of infant lungs and well-developed lymphoepithelium was evident in four cases. This study shows that BALT may be present in the human fetal and infant lung, but that its appearance is probably dependent on antigenic stimulation.

Bronchi↗
PubMed2004

Mucoepidermoid carcinoma of the bronchus presenting with a negative chest X-ray and normal pulmonary function in two teenagers: two case reports and review of the literature.

Two adolescents presented with a history of dyspnea upon exertion and cough. In both cases, the chest X-ray and pulmonary function testing, including flow-volume loop, were normal. A bronchial tumor was diagnosed by CT scan, which was ordered after each patient had an episode of hemoptysis. The sedimentation rate was the only abnormal laboratory test in both cases. Mucoepidermoid carcinoma of the bronchus, a rare tumor in childhood, was found at pathology in both cases. There was no evidence of metastases to local lymph nodes or distal sites. There were 47 previously reported cases in children. Recurrent pneumonia and persistent cough were the most common presenting findings. These tumors are of low-grade malignant potential but they can become locally invasive, extending into cartilage and surrounding soft tissue. Prognosis is good with complete resection.

Adolescent↗
PubMed1995

The maintenance of functional activity in human isolated bronchus after cryopreservation.

Cryopreservation has been successfully used in the in vitro study of pharmacological responses of animal tissues and, to a limited extent, of human tissue. In this study, we examined the effect of cryopreservation on reactivity of human bronchus which was stored for a period of up to 3 weeks. Thirty-two bronchial rings were obtained from each of four transplantation donors (four male, aged 32 +/- 15 years SD). Eight rings from each patient were studied on day 0 (the day of retrieval) and an additional eight on days 7, 14 and 21, after cryopreservation in 1.8 M dimethyl sulfoxide in 1 ml foetal bovine serum at -190 degrees C. On day 0, all tissues from all patients contracted in response to either histamine or carbachol or relaxed in response to isoprenaline or levcromakalim. There was no significant difference in the mean Tmax or pD2 values for any agonist on days 7, 14 and 21 when responses were compared with those obtained on day 0. The major change induced by cryopreservation was observed in the response to antigen. Tissues from three of the four donors contracted to the administration of Dermatophagoides pteronyssinus on day 0. However, when tissues from these same donors were studied on days 7, 14 and 21, they did not contract to this antigen. The results of this study indicate that human bronchial tissue may be successfully cryopreserved to maintain contractile and relaxant responses to various agonists. However, the response to antigen in tissues, which on day 0 of study were determined to be sensitized, was not present after cryopreservation.

Adult↗
PubMed2002

Role of interferon-gamma in the development of murine bronchus-associated lymphoid tissues induced by silica in vivo.

Exposure to silica is associated with the development of chronic airflow obstruction as well as pulmonary fibrosis, probably mediated in part by silica-induced small airway disease. To elucidate the mechanism of mucosal immune responses in the small airways, we analyzed the roles of interferon-gamma (IFN-gamma) using mice deficient of this cytokine in silicotic lung. IFN-gamma knockout mice (-/-) and wild-type C57BL/6 mice were treated with either a single fibrogenic dose of silica or an equivalent volume of saline and euthanized 21 days after intratracheal instillation. Total cell counts in bronchoalveolar lavage fluids increased in silica-instilled mice compared to saline-instilled mice, but there were no significant differences between IFN-gamma knockout mice and wild-type mice treated with silica. Morphometric estimation for fibrotic lesions within the lung did not show any differences between these mice. However, bronchus-associated lymphoid tissues (BALT), which are known to be involved in the mucosal immune responses, were significantly larger in the lungs of IFN-gamma knockout mice than in those of wild-type mice treated with silica. In addition, we evaluated the development of BALT in interleukin 4 (IL-4) knockout mice in order to clarify the effect of Th2 cytokine. Morphometric estimation for BALT did not show any differences between IL-4 knockout mice and wild-type mice in silicotic lung. These results suggest that IFN-gamma has an inhibitory effect on the development of BALT and may be involved in small airway disease in silicotic lung.

Animals↗