Bronchial Tissue (bronchial + tissue)

Distribution by Scientific Domains


Selected Abstracts


Blue-Violet Excited Autofluorescence Spectroscopy and Imaging of Normal and Cancerous Human Bronchial Tissue after Formalin Fixation

PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 2 2007
Tanja Gabrecht
Autofluorescence (AF) imaging is a powerful tool for the detection of (pre-)neoplastic lesions in the bronchi. Several endoscopic imaging systems exploit the spectral and intensity contrast of AF between healthy and (pre-)neoplastic bronchial tissues, yet, the mechanisms underlying these contrasts are poorly understood. In this report, the effect of formalin fixation on the human bronchi AF, hence on the contrast, was studied by spectrofluorometric point measurements and DAFE (Diagnostic AutoFluorescence Endoscopy) broad field imaging. Generally, formalin-fixed samples have higher AF intensity than in vivo, whereas the emission spectral shape is similar. Additionally, the spectrofluorometric data showed a moderate decrease of the AF intensity on (pre-)neoplastic lesions relative to the healthy bronchial samples. However, this decrease was lower than that reported from in vivo measurements. Neither spectral measurements nor imaging revealed spectral contrast between healthy bronchial tissue and (pre-)neoplastic lesions in formalin. These results indicate that epithelial thickening and blood supply in the adjacent lamina propria are likely to play a key role in the generation of the AF contrast in bronchial tissues. Our results show that the AF contrast in bronchial tissues was significantly affected by standard, 10% buffered, formalin fixation. Therefore, these samples are not suited to AF contrast studies. [source]


Endothelin-1 increases cholinergic nerve-mediated contraction of human bronchi via tachykinin synthesis induction

BRITISH JOURNAL OF PHARMACOLOGY, Issue 7 2001
Bruno D'Agostino
In some asthmatics, muscarinic receptor antagonists are effective in limiting bronchoconstrictor response, suggesting an abnormal cholinergic drive in these subjects. There is a growing body of evidences indicating that cholinergic neurotransmission is also enhanced by endothelin-1 (ET-1) in rabbit bronchi, mouse trachea and in human isolated airway preparations. We investigated the role of secondary mediators in ET-1 induced potentiation of cholinergic nerve-mediated contraction in human bronchi, in particular the possible role of neuropeptides in this phenomenon. Bronchial tissues after endothelin treatment were exposed to a standard electrical field stimulation (EFS) (30% of EFS 30Hz)-induced contraction. In addition, in some experiments, preparations were treated with a tachykinin NK2 receptor antagonist and subsequently exposed to the same protocol. HPLC and RIA were performed on organ bath fluid samples. Moreover, the human bronchi were used for the ,-PPT (preprotachykinin) mRNA extraction and semiquantitative reverse transcription polymerase chain reaction (RT , PCR), prior to and 30 , 40 min following ET-1 challenge. The selective tachykinin NK2 receptor antagonist, SR48968, was effective to reduce ET-1 potentiation of EFS mediated contraction. HPLC or RIA showed significant increased quantities of NKA in organ bath effluents after EFS stimulation in bronchi pretreated with ET-1. Finally, ,-PPT mRNA level after stimulation of bronchi with ET-1 was increased about 2 fold respect to control untreated bronchi. In conclusion, this study demonstrated that, at least in part, the ET-1 potentiation of cholinergic nerve-mediated contraction is mediated by tachykinin release, suggesting that in addition to nerves, several type of cells, such as airway smooth muscle cell, may participate to neuropeptide production. British Journal of Pharmacology (2001) 134, 1447,1454; doi:10.1038/sj.bjp.0704395 [source]


Biotransformation in vitro of the 22R and 22S epimers of budesonide by human liver, bronchus, colonic mucosa and skin

FUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 1 2001
Julio Cortijo
The pharmacological effects of glucocorticoids are greatly influenced by their pharmacokinetic properties. In the present report, the in vitro biotransformation of the 22R and 22S epimers of the topical steroid budesonide was studied in the S-9 fraction of human liver, bronchus, skin and colonic mucosa. The disappearance of unchanged epimers of budesonide was measured during 90 min of incubation by high performance liquid chromatography. The rate of disappearance was high in human liver while little biotransformation occurred in bronchial tissue and colonic mucosa, and none was detected in the skin. A marked decay of the initial concentration of unchanged budesonide epimers was noticed after 2 h incubation in cultured human hepatocytes, while only a small decrease was observed after 24 h incubation in cultured human airway smooth muscle cells and BEAS-2B cells. The 22R epimer of budesonide suffered greater in vitro biotransformation than the 22S epimer in human hepatic, bronchial and colonic tissues. These findings extend those of other studies, and confirm that the high therapeutic ratio of budesonide is due to negligible local biotransformation combined with high level of liver metabolism for locally absorbed budesonide. [source]


Blue-Violet Excited Autofluorescence Spectroscopy and Imaging of Normal and Cancerous Human Bronchial Tissue after Formalin Fixation

PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 2 2007
Tanja Gabrecht
Autofluorescence (AF) imaging is a powerful tool for the detection of (pre-)neoplastic lesions in the bronchi. Several endoscopic imaging systems exploit the spectral and intensity contrast of AF between healthy and (pre-)neoplastic bronchial tissues, yet, the mechanisms underlying these contrasts are poorly understood. In this report, the effect of formalin fixation on the human bronchi AF, hence on the contrast, was studied by spectrofluorometric point measurements and DAFE (Diagnostic AutoFluorescence Endoscopy) broad field imaging. Generally, formalin-fixed samples have higher AF intensity than in vivo, whereas the emission spectral shape is similar. Additionally, the spectrofluorometric data showed a moderate decrease of the AF intensity on (pre-)neoplastic lesions relative to the healthy bronchial samples. However, this decrease was lower than that reported from in vivo measurements. Neither spectral measurements nor imaging revealed spectral contrast between healthy bronchial tissue and (pre-)neoplastic lesions in formalin. These results indicate that epithelial thickening and blood supply in the adjacent lamina propria are likely to play a key role in the generation of the AF contrast in bronchial tissues. Our results show that the AF contrast in bronchial tissues was significantly affected by standard, 10% buffered, formalin fixation. Therefore, these samples are not suited to AF contrast studies. [source]


HER-2/neu overexpression in patients with radically resected nonsmall cell lung carcinoma

CANCER, Issue 10 2002
Impact on long-term survival
Abstract BACKGROUND Using immunohistochemistry, the authors prospectively investigated the expression of HER-2/neu protein in radically resected specimens of nonsmall cell lung carcinoma (NSCLC) and evaluated its impact on long-term prognosis. METHODS Between January 1991 and February 1992, surgical specimens from 130 consecutive patients who underwent radical resection for NSCLC (60 squamous cell carcinoma, 48 adenocarcinoma cases, and 22 large cell carcinomas) and that were staged (according to the TNM staging system) pathologically as Stage I (41 cases [ 32%]), Stage II (37 cases [28%]), and Stage IIIA (52 cases [40%]) were investigated for the expression of HER-2/neu using an avidin-biotin complex immunohistochemical technique. A semiquantitative four-stage grading system was used (0%, 1,5%, 6,20%, and > 20% positive cells) and an average number of 1500 cells/section was considered. Data were correlated with clinical and pathologic variables. RESULTS Normal bronchial tissue was found to be completely negative for HER-2/ neu expression whereas 21 of the 130 tumor specimens (16%) were positive (range 1,> 20%). HER-2/neu positivity did not appear to differ significantly among pathologic stages and histotypes. Using a predetermined cutoff value of 5% positive cells, 15 tumor specimens (12%) were found to be above this value. The median survival time (85 weeks vs. 179 weeks) and overall survival rate were significantly lower in patients with > 5% HER-2/neu -positive tumors (hazard ratio for the group with > 5% positive cells: 2.94, 95% confidence interval, 1.62,5.34; P < 0.0004). On multivariate analysis, HER-2/ neu and extent of tumor emerged as independent factors for disease-related mortality. CONCLUSIONS In NSCLC, the negative impact of HER-2/neu overexpression on survival was maintained in the long-term follow-up of radically resected patients. HER-2/neu overexpression may be a valuable prognostic factor as well as a potential target for biologic therapies. Cancer 2002;94:2669,74. © 2002 American Cancer Society. DOI 10.1002/cncr.10531 [source]


Aggravation of bronchial eosinophilia in mice by nasal and bronchial exposure to Staphylococcus aureus enterotoxin B

CLINICAL & EXPERIMENTAL ALLERGY, Issue 8 2006
P. W. Hellings
Summary Background The role of bacterial enterotoxins like Staphylococcus aureus enterotoxin B (SEB) in allergic asthma remains unknown. We used a mouse model of airway allergy to study the effects of nasal or bronchial contact with SEB on bronchial allergic inflammation. Methods The features of allergic asthma were induced in ovalbumin (OVA)-sensitized mice (days 1,13) by repeated exposures to nebulized OVA (days 33,37). Nasal or bronchial application of SEB was performed on three occasions (days 33,35,37), and the effects on bronchial inflammation, IgE titres and expression levels of mRNA for T helper type 2 cytokines and other inflammatory mediators were evaluated. Results Both nasal and bronchial SEB enhanced the allergen-induced bronchial inflammation, as reflected by more eosinophilic inflammation in the airway lumen and in bronchial tissue. Aggravation of experimental asthma correlated with higher expression of mRNA for IL-5, IL-4, IFN-,, IL-12 p40, eotaxin-1 and TGF-, in bronchi. In addition, nasal SEB elevated concentrations of IL-4, IL-5 and IFN-, in serum and bronchial SEB increased titres of OVA-specific and total IgE in serum. Conclusion Our data illustrate the potential of both nasal as well as bronchial SEB to aggravate several features of allergic asthma in a mouse model. [source]


Blue-Violet Excited Autofluorescence Spectroscopy and Imaging of Normal and Cancerous Human Bronchial Tissue after Formalin Fixation

PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 2 2007
Tanja Gabrecht
Autofluorescence (AF) imaging is a powerful tool for the detection of (pre-)neoplastic lesions in the bronchi. Several endoscopic imaging systems exploit the spectral and intensity contrast of AF between healthy and (pre-)neoplastic bronchial tissues, yet, the mechanisms underlying these contrasts are poorly understood. In this report, the effect of formalin fixation on the human bronchi AF, hence on the contrast, was studied by spectrofluorometric point measurements and DAFE (Diagnostic AutoFluorescence Endoscopy) broad field imaging. Generally, formalin-fixed samples have higher AF intensity than in vivo, whereas the emission spectral shape is similar. Additionally, the spectrofluorometric data showed a moderate decrease of the AF intensity on (pre-)neoplastic lesions relative to the healthy bronchial samples. However, this decrease was lower than that reported from in vivo measurements. Neither spectral measurements nor imaging revealed spectral contrast between healthy bronchial tissue and (pre-)neoplastic lesions in formalin. These results indicate that epithelial thickening and blood supply in the adjacent lamina propria are likely to play a key role in the generation of the AF contrast in bronchial tissues. Our results show that the AF contrast in bronchial tissues was significantly affected by standard, 10% buffered, formalin fixation. Therefore, these samples are not suited to AF contrast studies. [source]


The immunohistochemical expression of BNIP3 protein in non-small-cell lung cancer: a tissue microarray study

APMIS, Issue 8 2010
IVO ÜBERALL
Überall I, Kolek V, Klein J, Krej,í V, ,,astná J, Radová L, ,karda J, Fridman E. The immunohistochemical expression of BNIP3 protein in non-small-cell lung cancer: a tissue microarray study. APMIS 2010; 118: 565,70. Drug resistance is one of the reasons for chemotherapy failure in non-small-cell lung carcinoma (NSCLC). One of the major mechanisms of drug resistance is the inhibition of chemotherapy-induced apoptosis. Therefore, the study of novel cell death pathways could possibly enable us to overcome resistance to apoptosis in NSCLC. One of the non-caspase types of cell death is autophagy. BNIP3 protein, a Bcl-2 family member, highly expressed in some tumours, plays a key role in the induction of autophagy. In the present study, we investigated the immunohistochemical expression and subcellular localization of BNIP3 in a series of early- and late-stage non-small-cell lung carcinomas and normal bronchial tissues, and correlated this expression with the occurrence of metastasis and survival. BNIP3 was strongly expressed in the nucleus of cancer cells in 16/79 (20.3%) cases. This BNIP3 positivity did not correlate with histological grade, stage, histology type, metastatic potential, or expression of BNIP3 according to median values. No significant correlation was observed between the expression of BNIP3 and the overall survival of NSCLC patients (p = 0.55). Nor did we find any significant correlation between BNIP3 expression and the occurrence of site-specific metastasis (p = 0.85). [source]