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International Journal of Molecular... Jan 2016Inhalation studies are the gold standard for the estimation of the harmful effects of respirable chemical substances, while there is limited evidence of the harmful... (Review)
Review
Inhalation studies are the gold standard for the estimation of the harmful effects of respirable chemical substances, while there is limited evidence of the harmful effects of chemical substances by intratracheal instillation. We reviewed the effectiveness of intratracheal instillation studies for estimating the hazards of nanoparticles, mainly using papers in which both inhalation and intratracheal instillation studies were performed using the same nanoparticles. Compared to inhalation studies, there is a tendency in intratracheal instillation studies that pulmonary inflammation lasted longer in the lungs. A difference in pulmonary inflammation between high and low toxicity nanoparticles was observed in the intratracheal instillation studies, as in the inhalation studies. Among the endpoints of pulmonary toxicity, the kinetics of neutrophil counts, percentage of neutrophils, and chemokines for neutrophils and macrophages, heme oxygenase-1 (HO-1) in bronchoalveolar lavage fluid (BALF), reflected pulmonary inflammation, suggesting that these markers may be considered the predictive markers of pulmonary toxicity in both types of study. When comparing pulmonary inflammation between intratracheal instillation and inhalation studies under the same initial lung burden, there is a tendency that the inflammatory response following the intratracheal instillation of nanoparticles is greater than or equal to that following the inhalation of nanoparticles. If the difference in clearance in both studies is not large, the estimations of pulmonary toxicity are close. We suggest that intratracheal instillation studies can be useful for ranking the hazard of nanoparticles through pulmonary inflammation.
Topics: Administration, Mucosal; Animals; Biomarkers; Humans; Instillation, Drug; Nanoparticles; Pneumonia; Respiratory Mucosa; Trachea
PubMed: 26828483
DOI: 10.3390/ijms17020165 -
Journal of Critical Care Mar 2009The study aimed to describe the patterns and density of early tracheal colonization among intubated patients and to correlate colonization status with levels of...
OBJECTIVE
The study aimed to describe the patterns and density of early tracheal colonization among intubated patients and to correlate colonization status with levels of antimicrobial peptides and inflammatory cytokines.
DESIGN
The was a prospective cohort study.
SETTING
The study was conducted in medical and cardiovascular intensive care units of a tertiary referral hospital.
PATIENTS
Seventy-four adult patients admitted between March 2003 and May 2006 were recruited for the study.
INTERVENTIONS
Tracheal aspirates were collected daily for the first 4 days of intubation using standardized, sterile technique and sent for quantitative culture and cytokines, lactoferrin and lysozyme measurements.
MEASUREMENTS AND MAIN RESULTS
The mean acute physiology and chronic health evaluation (APACHE II) score in this cohort was 24 +/- 7. Proportion of subjects colonized by any microorganism increased over the first 4 days of intubation (47%, 60%, 70%, 70%, P = .08), but density of colonization for bacteria or yeast did not change significantly. No known risk factors predicted tracheal colonization on day 1 of intubation. Several patterns of colonization were observed (persistent, transient, new colonization, and clearance of initial colonization).The most common organisms cultured were Candida albicans and coagulase-negative Staphylococcus. Levels of cytokines, lactoferrin, or lysozyme did not change over time and were not correlated with tracheal colonization status. Four subjects (6%) had ventilator-associated pneumonia.
CONCLUSIONS
The density of tracheal colonization did not change significantly over the first 4 days of intubation in medical intensive care unit patients. There was no correlation between tracheal colonization and the levels of antimicrobial peptides or cytokines. Several different patterns of colonization may have to be considered while planning interventions to reduce airway colonization.
Topics: APACHE; Adult; Candidiasis; Case-Control Studies; Colony Count, Microbial; Cross Infection; Cytokines; Female; Humans; Inflammation; Intensive Care Units; Intubation, Intratracheal; Lactoferrin; Logistic Models; Male; Middle Aged; Multivariate Analysis; Muramidase; Pneumonia, Ventilator-Associated; Prospective Studies; Respiration, Artificial; Respiratory Mucosa; Risk Factors; Staphylococcal Infections; Statistics, Nonparametric; Suction; Time Factors; Trachea
PubMed: 19272547
DOI: 10.1016/j.jcrc.2008.10.009 -
Stem Cells (Dayton, Ohio) Nov 2016Wnt signaling is required for lineage commitment of glandular stem cells (SCs) during tracheal submucosal gland (SMG) morphogenesis from the surface airway epithelium...
Wnt signaling is required for lineage commitment of glandular stem cells (SCs) during tracheal submucosal gland (SMG) morphogenesis from the surface airway epithelium (SAE). Whether similar Wnt-dependent processes coordinate SC expansion in adult SMGs following airway injury remains unknown. We found that two Wnt-reporters in mice (BAT-gal and TCF/Lef:H2B-GFP) are coexpressed in actively cycling SCs of primordial glandular placodes and in a small subset of adult SMG progenitor cells that enter the cell cycle 24 hours following airway injury. At homeostasis, these Wnt reporters showed nonoverlapping cellular patterns of expression in the SAE and SMGs. Following tracheal injury, proliferation was accompanied by dynamic changes in Wnt-reporter activity and the analysis of 56 Wnt-related signaling genes revealed unique temporal changes in expression within proximal (gland-containing) and distal (gland-free) portions of the trachea. Wnt stimulation in vivo and in vitro promoted epithelial proliferation in both SMGs and the SAE. Interestingly, slowly cycling nucleotide label-retaining cells (LRCs) of SMGs were spatially positioned near clusters of BAT-gal positive serous tubules. Isolation and culture of tet-inducible H2B-GFP LRCs demonstrated that SMG LRCs were more proliferative than SAE LRCs and culture expanded SMG-derived progenitor cells outcompeted SAE-derived progenitors in regeneration of tracheal xenograft epithelium using a clonal analysis competition assay. SMG-derived progenitors were also multipotent for cell types in the SAE and formed gland-like structures in xenografts. These studies demonstrate the importance of Wnt signals in modulating SC phenotypes within tracheal niches and provide new insight into phenotypic differences of SMG and SAE SCs. Stem Cells 2016;34:2758-2771.
Topics: Animals; Cell Cycle; Cell Proliferation; Epithelial Cells; Exocrine Glands; Gene Expression Regulation; Genes, Reporter; Green Fluorescent Proteins; Heterografts; Intercellular Signaling Peptides and Proteins; Ki-67 Antigen; Mice; Mice, Transgenic; Naphthalenes; Organoids; Primary Cell Culture; Respiratory Mucosa; Stem Cells; Tissue Culture Techniques; Trachea; Wnt1 Protein; Wnt3A Protein; beta-Galactosidase
PubMed: 27341073
DOI: 10.1002/stem.2443 -
Respiratory Physiology & Neurobiology Dec 2007Submucosal glands of the tracheobronchial airways provide the important functions of secreting mucins, antimicrobial substances, and fluid. This review focuses on the... (Review)
Review
Submucosal glands of the tracheobronchial airways provide the important functions of secreting mucins, antimicrobial substances, and fluid. This review focuses on the ionic mechanism and regulation of gland fluid secretion and examines the possible role of gland dysfunction in the lethal disease cystic fibrosis (CF). The fluid component of gland secretion is driven by the active transepithelial secretion of both Cl(-) and HCO(3)(-) by serous cells. Gland fluid secretion is neurally regulated with acetylcholine, substance P, and vasoactive intestinal peptide (VIP) playing prominent roles. The cystic fibrosis transmembrane conductance regulator (CFTR) is present in the apical membrane of gland serous cells and mediates the VIP-induced component of liquid secretion whereas the muscarinic component of liquid secretion appears to be at least partially CFTR-independent. Loss of CFTR function, which occurs in CF disease, reduces the capacity of glands to secrete fluid but not mucins. The possible links between the loss of fluid secretion capability and the complex airway pathology of CF are discussed.
Topics: Bronchi; Cystic Fibrosis; Exocrine Glands; Extracellular Fluid; Humans; Ion Transport; Lung; Respiratory Mucosa; Trachea
PubMed: 17707699
DOI: 10.1016/j.resp.2007.06.017 -
Anticancer Research 2007External irradiation (IRR) of advanced head and neck tumors often includes tissues of the larynx and trachea unaffected by cancer. In these normal tissues, both...
BACKGROUND
External irradiation (IRR) of advanced head and neck tumors often includes tissues of the larynx and trachea unaffected by cancer. In these normal tissues, both single-cell damage (necrosis, apoptosis, functional cell death) and interstitial damage (edema, fibrosis, vascular alterations, cellular infiltrations) resulting in tissue remodeling can occur, depending on various IRR parameters. However, reports on radiogenic intermediate filament protein alterations in laryngeal-tracheal tissues are very rare. In this study, we investigated the phenotypic characterization of the normal integrity-supporting cytokeratins (CK) and vimentin following a clinically relevant IRR protocol in laryngeal-tracheal tissues.
MATERIALS AND METHODS
In 61 laryngo-tracheal specimens from Wistar rats the expression profile and distribution pattern of CK (CK13, CK17/19, CK18) and vimentin were investigated according to IRR dose (fractionated IRR, 2 Gy per day, total dose of 20, 40 or 60 Gy), time from IRR (6 months vs. 12 months) and animal age (1 year vs. 1.5 years) using immunohistochemical methods, semiquantitative assessment and multivariate analysis.
RESULTS
In irradiated specimens, expression of both CK and vimentin showed slight to moderate dose-dependent alterations. The expression differed in frequency and level among the various tissue structures and showed remarkable heterogeneity, with increases, decreases and fluctuations in staining. In the glottic mucosal layer (non-keratinizing squamous epithelium), CK13 expression decreased with increasing dose. The CK17/19 expression of supra- and subglottic respiratory epithelia following 20 and 60 Gy exposure was significantly lower than in controls. The respiratory epithelia and, in part, the cuboidal epithelia of the indifferent type at the inner side of the aryepiglottic fold revealed increasing CK17/19 immunoreactions up to 40 Gy IRR, but a distinct decrease in expression at 60 Gy. In subglottic gland structures, CK18 was detected at significantly higher levels than in controls. There was increasing expression with increasing dose. CK18 reactions of supra- and subglottic respiratory mucosal layer, supraglottic gland structures and thyrocytes tended towards increasing expression with increasing dose and in older animals. Tracheal mucosal epithelia, tracheal glands, and respiratory epithelia of the inner side of the aryepiglottic fold tended towards decreasing expression of CK18 with increasing dose and in older animals. In part, these tissues showed dose-dependent fluctuations. Furthermore, the vimentin reactions showed dose-dependent, heterogeneous patterns, with increases, decreases, and fluctuations in staining. Moreover, there were differences in frequency and intensity of expression among the various tissue structures. Age and time from IRR had no significant effect on immunoreaction.
CONCLUSION
The staining of CK and vimentin predominantly showed a notable dose-dependent heterogeneity, with increases, decreases and fluctuations in expression. The expression pattern persisted for up to 1 year after the completion of irradiation. Thus, these findings must reflect late radiation effects. The altered expression of CK and vimentin may play at least a partial role in structural (e.g. edema) and functional (e.g. voice disorders) changes associated with irradiation of the head and neck.
Topics: Animals; Dose-Response Relationship, Radiation; Immunohistochemistry; Keratins; Larynx; Rats; Rats, Wistar; Respiratory Mucosa; Trachea; Vimentin
PubMed: 17649822
DOI: No ID Found -
The Laryngoscope Feb 2021Idiopathic subglottic stenosis (iSGS) is an inflammatory process leading to fibrosis and narrowing of the laryngotracheal airway. There is variability in patient...
OBJECTIVES
Idiopathic subglottic stenosis (iSGS) is an inflammatory process leading to fibrosis and narrowing of the laryngotracheal airway. There is variability in patient response to surgical intervention, but the mechanisms underlying this variability are unknown. In this pilot study, we measure expression of candidate targets at the mucosal surface of the subglottis in iSGS patients. We aim to identify putative biomarkers for iSGS that provide insights into the molecular basis of disease progression, yield a gene signature for the disease, and/or predict a response to therapy.
STUDY DESIGN
In vitro comparative study of human cells.
METHODS
Levels of candidate transcripts and proteins were measured in healthy and stenotic laryngotracheal tissue specimens taken from the mucosal surface in 16 iSGS patients undergoing endoscopic balloon dilation. Pre- and post-operative pulmonary function test and patient reported voice and breathing outcomes were also assessed. Unsupervised clustering was used to define patient subgroups based on expression profile.
RESULTS
Pulmonary function and voice and breathing outcome metrics demonstrated significant post-operative improvement. Transcript levels of αSMA, CCL2, COL1A1, COL3A1, FN1, IFNG, and TGFB1 and protein levels of CCL2, IFNG, and IL-6 were significantly upregulated in stenotic as compared to healthy tissues. Marked heterogeneity was observed in the patterns of expression of candidate markers across individuals and tissue types. Patient subgroups defined by expression profile did not show a statistically significant difference in dilation interval.
CONCLUSION
Pro-inflammatory and pro-fibrotic pathways are significantly upregulated along the mucosal surface of stenotic laryngotracheal tissues, and CCL2 and IFNG merit further investigation as potential iSGS biomarkers.
LEVEL OF EVIDENCE
4 Laryngoscope, 131:342-349, 2021.
Topics: Adult; Aged; Biomarkers; Dilatation; Disease Progression; Endoscopy; Female; Fibrosis; Humans; Laryngeal Mucosa; Laryngostenosis; Larynx; Male; Membrane Proteins; Middle Aged; Pilot Projects; Predictive Value of Tests; Respiratory Function Tests; Trachea; Transcriptome
PubMed: 32369195
DOI: 10.1002/lary.28712 -
The Journal of Thoracic and... Jul 2014Little is known about the role of Wnt/β-catenin in postnatal airway homeostasis and basal cell function. This study aimed to investigate the role of Wnt signaling in...
OBJECTIVES
Little is known about the role of Wnt/β-catenin in postnatal airway homeostasis and basal cell function. This study aimed to investigate the role of Wnt signaling in the self-renewal of basal cells and the involvement of β-catenin in tracheal repair after naphthalene-induced injury.
METHODS
Mice were treated with naphthalene and injected with 4-hydroxytamoxifen. Injury and repair of the tracheal epithelium after naphthalene-mediated secretory cell depletion was assessed by a immunohistochemical study. The involvement of Wnt and β-catenin signaling in basal cell proliferation was investigated during in vitro expansion.
RESULTS
Immunohistochemical analysis of tracheal epithelium in wild-type mice showed a reduction in the number of Clara cell secretory protein (CCSP+) and forkhead box transcription factor (Fox-J1+) cells on days 2 to 5 after naphthalene-induced injury; this cell population was regenerated by day 10. After flush labeling, bromodeoxyuridine-positive (BrdU+) cells and Ki67+ cells were observed in tracheal epithelium on days 2 to 5 but not on days 10 and 21. Confocal microscopy visualizing K5+ and BrdU+ cells showed that Wnt3a promotes proliferation of K5+ cells. Immunohistochemical analysis of K5+ and CCSP+ in tracheal epithelial cells from wild-type littermate and K5-Cre-mediated β-catenin knock-out mice showed that on day 3, the number of CCSP+ cells was decreased in all mice. On day 10, CCSP+ cells were present in wild-type littermate mice but absent in conditional knock-out mice.
CONCLUSIONS
Basal cells serve as stem cells in the tracheal epithelium, regenerating and maintaining tracheal epithelial cells in a mouse model of tracheal injury. β-Catenin is required for proliferation and self-renewal of tracheal epithelial cells.
Topics: Animals; Cell Proliferation; Cells, Cultured; Epithelial Cells; Forkhead Transcription Factors; Keratin-15; Keratin-5; Ki-67 Antigen; Mice; Mice, Inbred C57BL; Mice, Transgenic; Naphthalenes; Regeneration; Respiratory Mucosa; Stem Cells; Time Factors; Trachea; Uteroglobin; Wnt Signaling Pathway; beta Catenin
PubMed: 24280717
DOI: 10.1016/j.jtcvs.2013.10.039 -
Respiratory Research Feb 2018Planar cell polarity (PCP) coordinates the patterning and orientation of cells and their structures along tissue planes, and although its acquisition during the...
BACKGROUND
Planar cell polarity (PCP) coordinates the patterning and orientation of cells and their structures along tissue planes, and although its acquisition during the formation of airway epithelium has been described, the mechanisms for its maintenance and reconstruction are poorly understood. We aimed to clarify whether ambient environment change by orthotropic autologous transplantation affected PCP at the cellular level.
METHODS
We performed orthotropic autologous transplantation by inverting tracheal segments in rats, and then performed morphological evaluation by microscopy. The PCP of the tracheal epithelium was assessed over time by analyzing the directions of mucociliary transport and ciliary beat, the positional relationship between the basal body and basal foot, and the bias of Vang-like protein 1 (Vangl1) at 2, 4, and 6 months postoperatively.
RESULTS
After 2 months, the directions of mucociliary transport and ciliary beat were preserved toward the lung in the inverted tracheal segments. The positional relationship between the basal body and the basal foot, and the bias of Vangl1, also indicated preservation of PCP in the inverted tracheal segments. Similar results were obtained at 6 months.
CONCLUSION
The PCP of ciliated epithelium was preserved in reversed trachea, even after long-term observation.
Topics: Animals; Cell Polarity; Male; Rats; Rats, Wistar; Respiratory Mucosa; Time Factors; Trachea
PubMed: 29394896
DOI: 10.1186/s12931-018-0726-y -
Medicine Feb 2016Rosai-Dorfman Disease (RDD) is a rare non-neoplastic entity, also known as sinus histiocytosis with massive lymphadenopathy (SHML), characterized by a benign... (Review)
Review
Rosai-Dorfman Disease (RDD) is a rare non-neoplastic entity, also known as sinus histiocytosis with massive lymphadenopathy (SHML), characterized by a benign proliferation of histiocytes in lymph nodes. Localized forms of RDD involving the tracheobronchial tree are very rare. There is no consensus regarding the management of central airway forms and recurrence is frequent. We report the case of an 81-year-old Caucasian woman admitted in 2014 for chronic cough. Her main medical past history included a diagnosis of sinonasal RDD in 1996 with recurrent obstructive rhinosinusitis requiring repeated sinonasal surgery, and a diagnosis of tracheal RDD in 2010 with 2 asymptomatic smooth lesions (5 and 7 mm) on the anterior tracheal wall. Physical examination was normal in 2014. Pulmonary function tests showed an obstructive pattern. Computed tomographic scan revealed a mass arising from the anterior wall of the trachea that projects into the tracheal lumen. Fiberoptic bronchoscopy showed a hypervascular multilobular lesion (2 cm) arising from the anterior tracheal wall and causing 50% obstruction of the tracheal lumen. Mechanical resection with electrocoagulation of the tracheal mass was performed by rigid bronchoscopy with no complication. Histological examination demonstrated tracheal RDD. One year after endotracheal resection, the patient presented no recurrence of cough and the obstructive pattern had resolved. Reports on tracheobronchial involvement are scarce. Symptomatic tracheobronchial obstruction requires mechanical resection by rigid bronchoscopy or surgery. Recurrence is frequent, justifying long-term follow-up.
Topics: Aged, 80 and over; Female; Histiocytosis, Sinus; Humans; Radiography; Respiratory Mucosa; Trachea
PubMed: 26886634
DOI: 10.1097/MD.0000000000002821 -
Toxicology and Applied Pharmacology Dec 2020Hydraulic fracturing creates fissures in subterranean rock to increase the flow and retrieval of natural gas. Sand ("proppant") in fracking fluid injected into the well...
Hydraulic fracturing creates fissures in subterranean rock to increase the flow and retrieval of natural gas. Sand ("proppant") in fracking fluid injected into the well bore maintains fissure patency. Fracking sand dust (FSD) is generated during manipulation of sand to prepare the fracking fluid. Containing respirable crystalline silica, FSD could pose hazards similar to those found in work sites where silica inhalation induces lung disease such as silicosis. This study was performed to evaluate the possible toxic effects following inhalation of a FSD (FSD 8) in the lung and airways. Rats were exposed (6 h/d × 4 d) to 10 or 30 mg/m of a FSD collected at a gas well, and measurements were performed 1, 7, 27 and, in one series of experiments, 90 d post-exposure. The following ventilatory and non-ventilatory parameters were measured in vivo and/or in vitro: 1) lung mechanics (respiratory system resistance and elastance, tissue damping, tissue elastance, Newtonian resistance and hysteresivity); 2) airway reactivity to inhaled methacholine (MCh); airway epithelium integrity (isolated, perfused trachea); airway efferent motor nerve activity (electric field stimulation in vitro); airway smooth muscle contractility; ion transport in intact and cultured epithelium; airway effector and sensory nerves; tracheal particle deposition; and neurogenic inflammation/vascular permeability. FSD 8 was without large effect on most parameters, and was not pro-inflammatory, as judged histologically and in cultured epithelial cells, but increased reactivity to inhaled MCh at some post-exposure time points and affected Na transport in airway epithelial cells.
Topics: Administration, Inhalation; Animals; Dust; Epithelial Cells; Hydraulic Fracking; Inhalation Exposure; Lung; Male; Methacholine Chloride; Occupational Exposure; Rats; Rats, Sprague-Dawley; Respiratory Mucosa; Sand; Silicon Dioxide; Trachea
PubMed: 33068619
DOI: 10.1016/j.taap.2020.115284