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Trachea
Kinds of Trachea Selected AbstractsEffects of normobaric hyperoxia on water content in different organs in ratsACTA PHYSIOLOGICA, Issue 1 2002L. E. B. Stuhr ABSTRACT Pulmonary oxygen toxicity is a dose-dependent effect on alveolar epithelial and endothelial cells resulting in pulmonary oedema. Any concomitant effects on systemic capillary endothelium would be expected to result in capillary leakage and an increase in the tissues' water content. Total tissue water (TTW) in different organs was therefore studied in freely moving rats exposed to 100% O2 at normobaric pressure for 24 or 48 h, and compared to air-breathing control rats. The TTW for the following tissues was measured: Trachea, left bronchus, left lung, left and right ventricle, left kidney, skin (left paw-hindlimb), skin (back of the rat), left brain, left eye and thigh muscle left side. There was a significant increase in TTW of the lung accompanied by pleural effusion after 48 h of oxygen exposure as expected in all exposed animals. There was a small increase in TTW of the paw only, and a small decrease or no change in other tissues after 24 and 48 h of exposure. We conclude that there is no evidence of systemic capillary dysfunction as measured by tissue water content after exposure to hyperoxia in a dosage causing pulmonary oedema. [source] Light and Electron Microscopic Studies of the Trachea in the One-Humped Camel (Camelus dromedarius)ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 1 2007A. R. Raji Summary Histology of trachea of camel (Camelus dromedarius) was studied using light, scanning (SEM) and transmission electron microscopy (TEM). Tissue samples taken from the trachea (proximal, middle and distal part) were routinely prepared for histology (LM, EM) and stained with haematoxylin and eosin, Van Giesson (VG), Alcian blue, Periodic acid schiff (PAS), Masson's trichrome (MT), Verhof, PAS,VG and PAS,MT. The trachea of camel consists of 66,75 incomplete cartilaginous rings of hyaline. The lamina epithelium is composed of pseudostratified-ciliated columnar epithelium with many goblet cells. Submucosal layers were loose connective tissue with many elastic fibres. The mucosal and submucosal layers were 517.2 ± 61.6 ,m (n = 20) thick. Submucosal glands were tubuloalveolar with mucous (acidic and neutral) secretions. Trachealis muscle was attached to the inside sheet of tracheal cartilage. Ultrastructural studies showed that surface epithelium is pseudostratified with mucus-producing goblet cells, ciliated and basal cells, similar to other mammals. The ciliated cells contained many mitochondria, oval nucleus and many big granules. In scanning electron microscopy (SEM) studies, viscoelastic layers were observed on the epithelial surface of trachea, and there were highly condensed cilia under this layer. [source] Surgery of the Larynx, Trachea, Esophagus and Neck.ANZ JOURNAL OF SURGERY, Issue 8 2003Christopher J. O'Brien MS, FRACS No abstract is available for this article. [source] Contractile responses to adenosine, R-PIA and ovalbumen in passively sensitized guinea-pig isolated airwaysBRITISH JOURNAL OF PHARMACOLOGY, Issue 6 2002Timothy J Martin Responses to adenosine, R-PIA and ovalbumen were examined in guinea-pig isolated superfused tracheal spirals to determine the effects of passive sensitization by overnight incubation in serum from ovalbumen (OA)-sensitized or non-sensitized guinea-pigs. Tissues incubated with serum from non-sensitized and OA-sensitized guinea-pigs contracted (0.07±0.02 and 0.04±0.01 g, respectively) to adenosine (300 ,M) whereas non-incubated or Krebs-incubated tissues produced no contractions to adenosine or ovalbumen (10 ,g). Ovalbumen caused substantial contractions (0.40±0.09 g) after OA-sensitized serum incubation and significantly (P<0.05) smaller contractions (0.08±0.03 g) after non-sensitized serum incubation. Tracheae from guinea-pigs actively sensitized to ovalbumen 14,21 days beforehand also contracted to adenosine, R-PIA (3 ,M) and ovalbumen. The A1/A2 adenosine receptor antagonist, 8-phenyltheophylline (8-PT, 3 ,M), failed to antagonize these contractions, suggesting that A1/A2 adenosine receptors were not involved. Unlike adenosine, R-PIA (3 ,M) produced contractions in non-incubated (0.23±0.04 g) or Krebs-incubated (0.15±0.04 g) tracheae, as well as after passive and active sensitization. None of these responses were blocked by 8-PT. The A3 receptor agonist, IB-MECA, in the presence of 8-PT produced small contractions in passively sensitized tracheae (10 ,M, 0.02±0.003 g) and, in larger doses (100 ,M and 1 mM), contracted actively sensitized tracheae. In actively sensitized trachea, the A3 receptor antagonist, MRS-1220 (100 nM), significantly (P<0.05) attenuated adenosine contractions in the presence of 8-PT from 0.23±0.07 g to 0.07±0.03 g. These results show that passive, like active sensitization, reveals bronchoconstrictions to adenosine of isolated tracheae. The insensitivity to 8-PT blockade, the antagonism by MRS-1220, and the fact that the A3 receptor agonist, IB-MECA, mimics this response, suggest involvement of A3 receptors. R-PIA, however, has a different profile of adenosine receptor activity. British Journal of Pharmacology (2002) 137, 729,738. doi:10.1038/sj.bjp.0704902 [source] Arms, Ovaries and Tracheas,What Next?AMERICAN JOURNAL OF TRANSPLANTATION, Issue 3 2009Article first published online: 19 FEB 200 In part two of a report on discarded and non-recovered organs, The AJT Report looks at rates for abdominal organs. We also take a look at some uncommon transplants, and what they may mean for the field of transplantation. [source] Salvage laryngectomy and pharyngocutaneous fistulae after primary radiotherapy for head and neck cancer: A national survey from DAHANCAHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 9 2003Cai Grau MD, DMSc Objective. In 1998, the Danish Society for Head and Neck Oncology decided to conduct a nationwide survey at the five head and neck oncology centers with the aim of evaluating the surgical outcome of salvage laryngectomy after radiotherapy with special emphasis on identifying factors that could contribute to the development of pharyngocutaneous fistulae. Patients. A total of 472 consecutive patients undergoing postirradiation salvage laryngectomy in the period July 1, 1987,June 30, 1997 were recorded at the five head and neck oncology centers in Denmark. Age ranged from 36 to 84 years, median 63 years, 405 men and 67 women. Primary tumor site was glottic larynx (n = 242), supraglottic larynx (n = 149), other larynx (n = 45), pharynx (n = 27), and other (n = 9). All patients had received prior radiotherapy. Results. Median time between radiotherapy and laryngectomy was 10 months (range, 1,348 months). A total of 89 fistulae lasting at least 2 weeks were observed, corresponding to an overall average fistulae risk of 19%. The number of performed laryngectomies per year decreased linearly (from 58 to 37), whereas the annual number of fistulae increased slightly (from 7 to 11), which meant that the corresponding estimated fistulae risk increased significantly from 12% in 1987 to 30% in 1997. Other significant risk factors for fistulae in univariate analysis included younger patient age, primary advanced T and N stage, nonglottic primary site, resection of hyoid bone, high total radiation dose, and large radiation fields. Multiple logistic regression analysis of these parameters suggested that nonglottic tumor site, late laryngectomy period (1987,1992 vs 1993,1997), and advanced initial T stage were independent prognostic factors for fistulae risk. Surgical parameters like resection of thyroid/tongue base/trachea or radiotherapy parameters like overall treatment time or fractions per week did not influence fistulae risk. Conclusions. The risk of fistulae is especially high in patients initially treated with radiotherapy for nonglottic advanced stage tumors. A significant decrease in the number of performed salvage laryngectomies over the 10 years was seen. Over the same time period, the annual number of fistulae remained almost constant. The resulting more than doubling of fistulae rate could thus in part be explained by less surgical routine. © 2003 Wiley Periodicals, Inc. Head Neck 25: 711,716, 2003 [source] Stylet Bend Angles and Tracheal Tube Passage Using a Straight-to-cuff ShapeACADEMIC EMERGENCY MEDICINE, Issue 12 2006Richard M. Levitan MD Abstract Objectives Malleable stylets improve maneuverability and control during tube insertion, but after passage through the vocal cords the stiffened tracheal tube may impinge on the tracheal rings, preventing passage. The goal of this study was to assess insertion difficulty with styletted tubes of different bend angles. Methods Tube passage was assessed with four different bend angles (25°, 35°, 45°, and 60°) using straight-to-cuff,shaped tubes. In two separate airway procedure classes, 16 operators in each class (32 total) placed randomly ordered styletted tubes of the different angles into eight cadavers (16 total). Operators subjectively graded the ease of tube passage as no resistance, some resistance, or impossible to advance. Results No resistance was reported in 69.1% (177/256) at 25°, in 63.7% (163/256) at 35°, in 39.4% (101/256) at 45°, and in 8.9% (22/256) at 60°. Tube passage was impossible in 2.3% of insertions (6/256) at 25°, in 3.5% (9/256) at 35°, in 11.3% (29/256) at 45°, and in 53.9% (138/256) at 60°. The odds ratios of impossible tube passage for 35°, 45°, and 60° vs. 25° were 1.52 (95% confidence interval [CI] = 0.55 to 4.16), 5.32 (95% CI = 2.22 to 12.71), and 48.72 (95% CI = 21.35 to 111.03), respectively. Conclusions Bend angles beyond 35° with straight-to-cuff styletted tracheal tubes increase the risk of difficult and impossible tube passage into the trachea. The authors did not compare different stylet stopping points, stylets of different stiffness, or tracheal tubes with different tip designs, all variables that can affect tube passage. [source] Application for regenerative medicine of epithelial cell culture-vistas of cultured epitheliumCONGENITAL ANOMALIES, Issue 3 2006Hajime Inoue ABSTRACT This review describes culture techniques for the epithelial system as well as trends in the clinical application of cultured keratinocytes in our department and the possibility of applying the techniques to other organs. Cultured epithelium and cultured dermis in particular have considerably preceded regeneration of other organs in the field of regenerative medicine. Since 1988 we have grafted cultured keratinocytes by the Rheinwald-Green modified method in at least 500 patients with large skin defects. As a result of the establishment of a culture technique for individual patients, it is now possible to prepare enough regenerated epithelium to cover the body surface area of as many as 10 adult patients in approximately three weeks after collecting 1 cm2 of skin, and then remaining cultured keratinocytes can be cryo-preserved for two-stage dermatoplasty at another site. This procedure makes it possible to avoid frequent skin collection from the same patient and thereby improves patients' quality of life and activities of daily living. On the other hand, to solve the problem of regenerated epithelium shrinking and problems with graft efficiency on dermis defect lesion, we have developed a proteinase-resistant regenerated dermis by mixing a certain protein with a fibrin scaffold. Recently we also took the initiative in grafting hybrid-type regenerated trachea in an animal experiment by using the epithelial and dermal cell culture technique, and some results of the graft were obtained. [source] Lactoferrin and anti-lactoferrin antibodies: Effects of ironloading of lactoferrin on albumin extravasation in different tissues in ratsACTA PHYSIOLOGICA, Issue 1 2000Erga Lactoferrin is a cationic iron-binding protein, which is released from activated neutrophils in concert with reactive oxygen species. In vitro, lactoferrin has both anti- and proinflammatory effects; many of them dependent on iron-binding. In vivo, only iron-free lactoferrin reduced inflammatory hyperpermeability in the lung. We therefore examined whether 1 mg iron-free (Apo-Lf) or iron-saturated lactoferrin (Holo-Lf) alone or followed by anti-lactoferrin antibodies (aLf) affected permeability evaluated by extravasation of radiolabelled bovine serum albumin (CBSA) in different tissues of anaesthetized rats. Fifteen minutes after i.v. injection of Lf, aLf or saline was given and circulatory arrest was induced 20 min thereafter. Measurements were performed in control, after Apo-Lf, Holo-Lf, Apo-Lf + aLf, Holo-Lf + aLf and aLf alone (n=6,8 in each group). No intergroup differences were found for plasma volume and haematocrit at the start and end of the 37 min extravasation period or for total tissue water in any of the six different tissues studied, excluding larger transcapillary fluid shifts. However, increases in CBSA were seen without differences in tissue intravascular volume. Iron-free lactoferrin and aLf alone did not change CBSA significantly. Iron-saturated lactoferrin significantly increased CBSA in skin (neck), trachea and left ventricle of the heart to 249 ± 9, 284 ± 16 and 160 ± 7% of control, respectively. When followed by aLf, both Apo- and Holo-Lf increased CBSA significantly in four and five of the tissues studied, respectively. However, no significant effect was seen for Holo-Lf + aLf compared with Holo-Lf alone. In conclusion, iron-saturated, but not iron-free lactoferrin increased CBSA, whereas antilactoferrin increased CBSA compared with lactoferrin alone only when following iron-free lactoferrin. [source] Staying alive: Dalmatian mediated blocking of apoptosis is essential for tissue maintenanceDEVELOPMENTAL DYNAMICS, Issue 6 2010Bilal E. Kerman Abstract In an EMS screen for mutations disrupting tracheal development, we identified new alleles of the dalmation (dmt) gene, which had previously been shown to affect peripheral nervous system (PNS) development. Here, we demonstrate that dmt loss results in programmed cell death, disrupting PNS patterning and leading to large gaps in the salivary duct and trachea. Dmt loss results in increased expression of the proapoptotic regulator genes head involution defective (hid) and reaper (rpr), and deletion of these genes or tissue-specific expression of the baculoviral apoptotic inhibitor P35 rescues the dmt defects. dmt is also required to protect cells from irradiation induced expression of hid and rpr during the irradiation resistant stage, which begins as cells become irreversibly committed to their final fates. Thus, we propose that Dmt keeps cells alive by blocking activation of hid and rpr as cells become irreversibly committed. Developmental Dynamics 239:1609,1621, 2010. © 2010 Wiley-Liss, Inc. [source] An Evaluation of a Blind Rotational Technique for Selective Mainstem IntubationACADEMIC EMERGENCY MEDICINE, Issue 10 2004Aaron E. Bair MD Abstract Objectives: Although rare, massive hemoptysis and major bronchial disruptions are associated with high mortality. Selective ventilation of the uninvolved lung can increase the likelihood of survival. Specialized devices used for single lung ventilation are often not readily available and can be difficult to place in the emergency department. The authors evaluated a blind rotational technique for selective mainstem intubation using either a standard endotracheal tube (ET) or a directional-tip endotracheal tube (DTET). Methods: This was a prospective, randomized trial on 25 human cadavers. The desired side of mainstem intubation was determined by randomization. Each cadaver was used for four ET, four DTET, and four control intubations. In the ET group, the trachea was intubated. The tube was then rotated 90° in the direction of the desired placement and advanced until resistance was met. In the DTET group, the technique was identical, except the trigger was activated to flex the tip during advancement. In the control group, an ET was advanced in neutral alignment until resistance was met. A bronchoscopist blinded to the desired placement determined tube position. Comparison testing was performed using Pearson's chi-square test. Results: When attempting to intubate the left mainstem, use of the ET with the rotational technique was successful 72.3% of the time (95% confidence interval [95% CI] = 57% to 84%). Intubation of the left mainstem using the DTET was successful 68.5% of the time (95% CI = 54% to 81%; p = 0.67). Attempts to selectively intubate the right mainstem using the rotational technique were highly successful in both groups: 94% for the ET (95% CI = 84% to 99%) versus 97.8% for the DTET (95% CI = 89% to 100%). Among controls, the right mainstem was intubated 93% of the time (95% CI = 86% to 97%). Conclusions: In a cadaveric model, the left mainstem bronchus can be selectively intubated with moderate reliability using this rotational technique. Use of a DTET confers no significant advantage. The ability to generalize these findings to living subjects is unknown. [source] Emergency Physician,Verified Out-of-hospital Intubation: Miss Rates by ParamedicsACADEMIC EMERGENCY MEDICINE, Issue 6 2004James H. Jones MD Abstract Objectives: To prospectively quantify the number of unrecognized missed out-of-hospital intubations by ground paramedics using emergency physician verification as the criterion standard for verification of endotracheal tube placement. Methods:The authors performed an observational, prospective study of consecutive intubated patients arriving by ground emergency medical services to two urban teaching hospitals. Endotracheal tube placement was verified by emergency physicians and evaluated by using a combination of direct visualization, esophageal detector device (EDD), colorimetric end-tidal carbon dioxide (ETCO2), and physical examination. Results: During the six-month study period, 208 out-of-hospital intubations by ground paramedics were enrolled, which included 160 (76.9%) medical patients and 48 (23.1%) trauma patients. A total of 12 (5.8%) endotracheal tubes were incorrectly placed outside the trachea. This comprised ten (6.3%) medical patients and two (4.2%) trauma patients. Of the 12 misplaced endotracheal tubes, a verification device (ETCO2 or EDD) was used in three cases (25%) and not used in nine cases (75%). Conclusions: The rate of unrecognized, misplaced out-of-hospital intubations in this urban, midwestern setting was 5.8%. This is more consistent with results of prior out-of-hospital studies that used field verification and is discordant with the only other study to exclusively use emergency physician verification performed on arrival to the emergency department. [source] Diseases of the equine tracheaEQUINE VETERINARY EDUCATION, Issue 3 2005T. S. Mair First page of article [source] Development of equine upper airway fluid mechanics model for Thoroughbred racehorsesEQUINE VETERINARY JOURNAL, Issue 3 2008V. RAKESH Summary Reason for performing study: Computational fluid dynamics (CFD) models provide the means to evaluate airflow in the upper airways without requiring in vivo experiments. Hypothesis: The physiological conditions of a Thoroughbred racehorse's upper airway during exercise could be simulated. Methods: Computed tomography scanned images of a 3-year-old intact male Thoroughbred racehorse cadaver were used to simulate in vivo geometry. Airway pressure traces from a live Thoroughbred horse, during exercise was used to set the boundary condition. Fluid-flow equations were solved for turbulent flow in the airway during inspiratory and expiratory phases. The wall pressure turbulent kinetic energy and velocity distributions were studied at different cross-sections along the airway. This provided insight into the general flow pattern and helped identify regions susceptible to dynamic collapse. Results: The airflow velocity and static tracheal pressure were comparable to data of horses exercising on a high-speed treadmill reported in recent literature. The cross-sectional area of the fully dilated rima glottidis was 7% greater than the trachea. During inspiration, the area of highest turbulence (i.e. kinetic energy) was in the larynx, the rostral aspect of the nasopharynx was subjected to the most negative wall pressure and the highest airflow velocity is more caudal on the ventral aspect of the nasopharynx (i.e. the soft palate). During exhalation, the area of highest turbulence was in the rostral and mid-nasopharynx, the maximum positive pressure was observed at the caudal aspect of the soft palate and the highest airflow velocity at the front of the nasopharynx. Conclusions and clinical relevance: In the equine upper airway collapsible area, the floor of the rostral aspect of the nasopharynx is subjected to the most significant collapsing pressure with high average turbulent kinetic during inhalation, which may lead to palatal instability and explain the high prevalence of dorsal displacement of the soft palate (DDSP) in racehorses. Maximal abduction of the arytenoid cartilage may not be needed for optimal performance, since the trachea cross-sectional area is 7% smaller than the rima glottidis. [source] Airway inflammation in Michigan pleasure horses: prevalence and risk factorsEQUINE VETERINARY JOURNAL, Issue 4 2006N. E. Robinson Summary Reasons for performing study: Although subclinical airway inflammation is thought to be common in horses, there is little information on its prevalence and none on risk factors. Objective: To determine the prevalence and risk factors for an increased number of inflammatory cells and for mucus accumulation in the trachea of pleasure horses. Methods: Horses (n = 266) in stables (n = 21) in Michigan were examined endoscopically, once in winter and once in summer 2004. Visible tracheal mucoid secretions were graded 0,5 and inflammatory cell numbers counted in a tracheal lavage sample. Information collected about each horse included age, gender, presence of cough, percent time indoors and source of roughage. The repeated measures were analysed by generalised estimating equations and linear mixed models. Results: Horses eating hay, especially from round bales, had the most neutrophils, whereas horses feeding from pasture had the fewest. Being female and being outdoors in winter were associated with increased numbers of inflammatory cells. Older horses had fewer macrophages than young horses. More than 70% of horses had >20% neutrophils in tracheal lavage. Twenty percent of horses had a mucus accumulation score >1; 17% had both a mucus score >1 and >20% neutrophils. The significant risk factors for mucus accumulation >1 were age >15 years, feeding on hay as compared to pasture, and being outdoors for more than 80% time in winter. Even though mucus accumulation score >1 was a risk factor for cough, only half of such horses coughed. Cough and mucus accumulation were associated with increased number of neutrophils. Conclusions: In comparison to pasture feeding, hay feeding, particularly from round bales, was associated with an increased number of neutrophils in the airway. Being outdoors in winter was associated with increased numbers of inflammatory cells and with mucus accumulation. Because 70% of horses have >20% neutrophils, this value should not be used as the sole indicator of airway inflammation. Potential relevance: The study reinforces the importance of hay feeding and older age as risk factors for inflammatory airway disease. Horses that do not have ,heaves' may be best kept indoors when winters are cold. [source] Inflammatory airway disease, nasal discharge and respiratory infections in young British racehorsesEQUINE VETERINARY JOURNAL, Issue 3 2005J. L. N. WOOD Summary Reasons for performing study: Respiratory disease is important in young Thoroughbred racehorses, but the variation in the rates of occurrence between different ages and training groups has not been characterised. Objectives: To determine the rates of respiratory disease, particularly inflammatory airway disease (IAD), as well as evidence of infection, and their variation between age and group. Methods: Horses were examined monthly in 7 British flat training yards over a 3 year period. IAD was defined as increased mucus in the trachea with increased proportions of neutrophils in tracheal wash samples. Frequencies of disease outcomes were estimated from the data. Results: The prevalence of IAD was 13.8% and the incidence was 8.9 cases/100 horses/month. Rates varied with training and age groups, decreasing in older animals. The prevalence of nasal discharge (ND) was 4.1%. Rates of bacterial isolation were more common than viral infections. The incidence and prevalence of several bacterial species decreased with age. Conclusions: IAD and ND were common in young racehorses, varying significantly between training groups and decreasing with age, consistent with infection playing a role in aetiology. Potential relevance: The high prevalence of IAD in 2-year-old horses in Britain suggests that routine endoscopic examination may be helpful in providing early diagnosis and appropriate therapy. The transmission of bacteria and viruses within and between groups of young animals and the role of infection, stable environment and factors inherent to each horse, including their genetic make-up, in the multifactorial aetiology of the disease all merit further study. [source] Expression of the Artemia trachealess gene in the salt gland and epipodEVOLUTION AND DEVELOPMENT, Issue 5 2002Brian Mitchell SUMMARY The Drosophila trachealess gene encodes a basic-helix-loop-helix-PAS transcription factor that controls the formation of the trachea and salivary duct. An ortholog of trachealess was identified in the brine shrimp, Artemia franciscana, and was shown to be highly conserved by sequence identity. Expression of Artemia trachealess was observed at two sites during development: the naupliar salt gland and the juvenile thoracic epipod. These two organs function at their respective times of development in osmoregulation, an important aspect of brine shrimp physiology. This extends the range of putative functions of trachealess to include formation of osmoregulatory, respiratory, and ductile organs. [source] Mapping of the 45M1 epitope to the C-terminal cysteine-rich part of the human MUC5AC mucinFEBS JOURNAL, Issue 3 2008Martin E. Lidell Mucins are large glycoproteins protecting mucosal surfaces throughout the body. Their expressions are tissue-specific, but in disease states such as cystic fibrosis, inflammation and cancer, this specificity can be disturbed. MUC5AC is normally expressed in the mucous cells of the epithelia lining the stomach and the trachea, where it constitutes a major component of the gastric and respiratory mucus. A number of mAbs have been raised against the gastric M1 antigen, an early marker for colonic carcinogenesis. Several of these mAbs recognize epitopes present on MUC5AC, suggesting that MUC5AC is the antigen. However, some of the mAbs raised against the gastric M1 antigen are widely used as antibodies against MUC5AC, despite the fact that their specificity for MUC5AC has not been clearly shown. In this study, we have tested the reactivity of the latter antibodies against a recombinantly expressed C-terminal cysteine-rich part of human MUC5AC. We demonstrate for the first time that the widely used mAb 45M1, as well as 2-12M1 and 166M1, are true antibodies against MUC5AC, with epitopes located in the C-terminal cysteine-rich part of the mucin. [source] Transcription of mammalian cytochrome c oxidase subunit IV-2 is controlled by a novel conserved oxygen responsive elementFEBS JOURNAL, Issue 21 2007Maik Hüttemann Subunit 4 of cytochrome c oxidase (CcO) is a nuclear-encoded regulatory subunit of the terminal complex of the mitochondrial electron transport chain. We have recently discovered an isoform of CcO 4 (CcO4-2) which is specific to lung and trachea, and is induced after birth. The role of CcO as the major cellular oxygen consumer, and the lung-specific expression of CcO4-2, led us to investigate CcO4-2 gene regulation. We cloned the CcO4-2 promoter regions of cow, rat and mouse and compared them with the human promoter. Promoter activity is localized within a 118-bp proximal region of the human promoter and is stimulated by hypoxia, reaching a maximum (threefold) under 4% oxygen compared with normoxia. CcO4-2 oxygen responsiveness was assigned by mutagenesis to a novel promoter element (5,-GGACGTTCCCACG-3,) that lies within a 24-bp region that is 79% conserved in all four species. This element is able to bind protein, and competition experiments revealed that, within the element, the four core bases 5,-TCNCA-3, are obligatory for transcription factor binding. CcO isolated from lung showed a 2.5-fold increased maximal turnover compared with liver CcO. We propose that CcO4-2 expression in highly oxygenated lung and trachea protects these tissues from oxidative damage by accelerating the last step in the electron transport chain, leading to a decrease in available electrons for free radical formation. [source] Cloning, chromosomal localization and characterization of the murine mucin gene orthologous to human MUC4FEBS JOURNAL, Issue 13 2002Jean-Luc Desseyn We report here the full coding sequence of a novel mouse putative membrane-associated mucin containing three extracellular EGF-like motifs and a mucin-like domain consisting of at least 20 tandem repeats of 124,126 amino acids. Screening a cosmid and a BAC libraries allowed to isolate several genomic clones. Genomic and cDNA sequence comparisons showed that the gene consists of 25 exons and 24 introns covering a genomic region of ,,52 kb. The first intron is ,,16 kb in length and is followed by an unusually large exon (, 9.5 kb) encoding Ser/Thr-rich tandemly repeated sequences. Radiation hybrid mapping localized this new gene to a mouse region of chromosome 16, which is the orthologous region of human chromosome 3q29 encompassing the large membrane-anchored mucin MUC4. Contigs analysis of the Human Genome Project did not reveal any other mucin on chromosome 3q29 and, interestingly, our analysis allowed the determination of the genomic organization of the human MUC4 and showed that its exon/intron structure is identical to that of the mouse gene we cloned. Furthermore, the human MUC4 shares considerable homologies with the mouse gene. Based on these data, we concluded that we isolated the mouse ortholog of MUC4 we propose as Muc4. Expression studies showed that Muc4 is ubiquitous like SMC and MUC4, with highest levels of expression in trachea and intestinal tract. [source] Gastrointestinal, selective airways and urinary bladder relaxant effects of Hyoscyamus niger are mediated through dual blockade of muscarinic receptors and Ca2+ channelsFUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 1 2008Anwarul Hassan Gilani Abstract This study describes the spasmolytic, antidiarrhoeal, antisecretory, bronchodilatory and urinary bladder relaxant properties of Hyoscyamus niger to rationalize some of its medicinal uses. The crude extract of H. niger seeds (Hn.Cr) caused a complete concentration-dependent relaxation of spontaneous contractions of rabbit jejunum, similar to that caused by verapamil, whereas atropine produced partial inhibition. Hn.Cr inhibited contractions induced by carbachol (1 ,m) and K+ (80 mm) in a pattern similar to that of dicyclomine, but different from verapamil and atropine. Hn.Cr shifted the Ca2+ concentration,response curves to the right, similar to that caused by verapamil and dicyclomine, suggesting a Ca2+ channel-blocking mechanism in addition to an anticholinergic effect. In the guinea-pig ileum, Hn.Cr produced a rightward parallel shift of the acetylcholine curves, followed by a non-parallel shift with suppression of the maximum response at a higher concentration, similar to that caused by dicyclomine, but different from that of verapamil and atropine. Hn.Cr exhibited antidiarrhoeal and antisecretory effects against castor oil-induced diarrhoea and intestinal fluid accumulation in mice. In guinea-pig trachea and rabbit urinary bladder tissues, Hn.Cr caused relaxation of carbachol (1 ,m) and K+ (80 mm) induced contractions at around 10 and 25 times lower concentrations than in gut, respectively, and shifted carbachol curves to the right. Only the organic fractions of the extract had a Ca2+ antagonist effect, whereas both organic and aqueous fractions had anticholinergic effect. A constituent, ,-sitosterol exhibited Ca2+ channel-blocking action. These results suggest that the antispasmodic effect of H. niger is mediated through a combination of anticholinergic and Ca2+ antagonist mechanisms. The relaxant effects of Hn.Cr occur at much lower concentrations in the trachea and bladder. This study offers explanations for the medicinal use of H. niger in treating gastrointestinal and respiratory disorders and bladder hyperactivity. [source] Antibody response to influenza infection of mice: different patterns for glycoprotein and nucleocapsid antigensIMMUNOLOGY, Issue 4 2003Robert Sealy Summary Our previous studies of C57BL/6 mice intranasally infected with influenza virus (A/PR8) revealed a spike of virus-specific immunoglobulin A (IgA)-secreting antibody-forming cells (AFC) in the mediastinal lymph node (MLN) 7 days post-infection. Here we show that these AFC are directed only against viral glycoprotein, and not nucleocapsid antigens. The early IgA spike associates with a decline in glycoprotein-specific AFC during week 2 post-infection. In contrast to the glycoprotein-specific AFC, nucleocapsid-specific, IgA-secreting AFC develop gradually in the MLN and persist for more than 3 weeks post-infection. As peripheral lymph node reactions wane, the nucleocapsid-specific AFC appear as long-sustained populations in the bone marrow. Microanatomical examination of the respiratory tract in infected mice shows foci of infection established in the lung 2 days post-infection, from which virus spreads to infect the entire lining of the trachea by day 3. At this time, viral haemagglutinin can be seen within the MLN, probably on projections from infected dendritic cells. This feature disappears within a day, though viral antigen expression continues to spread throughout the respiratory tract. Total IgA- and IgG-secreting AFC appear histologically in large numbers during the first week post-infection, significantly preceding the appearance of germinal centres (revealed by peanut agglutinin staining in week 2). To explain these results, we suggest that the initial immunogenic encounter of B cells with viral antigens occurs about 3 days post-infection in the MLN, with antigens transported by dendritic cells from airway mucosa, the only site of viral replication. Viral glycoproteins expressed as integral membrane components on the surface of infected dendritic cells [probably in the absence of cognate T helper (Th) cells] promote members of expanding relevant B-cell clones to undergo an IgA switch and terminal local plasmacytoid differentiation. Anti-glycoprotein specificities are thus selectively depleted from progeny of activated B-cell clones which are channelled to participate in germinal centre formation (perhaps by cognate T helper cells when they become sufficiently frequent). One product of the germinal centre reaction is the long-sustained, bone marrow-resident population, which is accordingly rich in anti-nucleoprotein, but not anti-glycoprotein specificities. Of note, we find that AFC responses toward influenza virus and Sendai virus differ, even though viral replication is limited to the airway mucosa in each case. The response towards Sendai virus exhibits neither the early appearance of anti-glycoprotein AFC expressing IgA in draining lymph nodes, nor the subsequent relative deficit of this specificity from bone marrow AFC populations. [source] An ex vivo swine tracheal organ culture for the study of influenza infectionINFLUENZA AND OTHER RESPIRATORY VIRUSES, Issue 1 2010Sandro F. Nunes Background The threat posed by swine influenza viruses with potential to transmit from pig populations to other hosts, including humans, requires the development of new experimental systems to study different aspects of influenza infection. Ex vivo organ culture (EVOC) systems have been successfully used in the study of both human and animal respiratory pathogens. Objectives We aimed to develop an air interface EVOC using pig tracheas in the study of influenza infection demonstrating that tracheal explants can be effectively maintained in organ culture and support productive influenza infection. Methods Tracheal explants were maintained in the air interface EVOC system for 7 days. Histological characteristics were analysed with different staining protocols and co-ordinated ciliary movement on the epithelial surface was evaluated through a bead clearance assay. Explants were infected with a swine H1N1 influenza virus. Influenza infection of epithelial cells was confirmed by immunohistochemistry and viral replication was quantified by plaque assays and real-time RT-PCR. Results Histological analysis and bead clearance assay showed that the tissue architecture of the explants was maintained for up to 7 days, while ciliary movement exhibited a gradual decrease after 4 days. Challenge with swine H1N1 influenza virus showed that the EVOC tracheal system shows histological changes consistent with in vivo influenza infection and supported productive viral replication over multiple cycles of infection. Conclusion The air interface EVOC system using pig trachea described here constitutes a useful biological tool with a wide range of applications in the study of influenza infection. [source] Prenatal and early postnatal morphogenesis and growth of human laryngotracheal structuresJOURNAL OF ANATOMY, Issue 2 2008Pierre Fayoux Abstract Advances in neonatal medicine have resulted in increased care of fetal and neonatal airways. These advances have required an exhaustive knowledge of fetal airway anatomy and development. The aim of this study was to determine the anatomical development of laryngotracheal structures during the fetal and immediate postnatal period and to correlate these observations with other fetal biometric parameters to estimate developmental particularities of the fetal airway. An anatomical prospective study was based on examination of larynx and trachea from 300 routine autopsies of fetuses and infants, free of malformation and never intubated. Anatomical measurements of cricoid cartilage, thyroid cartilage, glottis, arytenoid cartilage and trachea were performed using a precision calliper and precision divider. Statistical analysis was performed to represent the growth of anatomical structures and to evaluate the correlation with biometric data. Raw data and 10th and 90th percentile curves were fitted satisfactorily with a linear model for gestational age. A linear relationship between laryngotracheal measurement and body weight and height was observed except for glottis length, interarytenoid distance and anterior cricoid height. The diameter of the cricoid lumen was significantly less than that of the trachea and glottis lumen. A sexual dysmorphism was noted for thyroid cartilage measurements and interarytenoid distance, with measurements significantly smaller in females. This study reports the anatomical development of normal laryngotracheal structures during the fetal period. Despite the fact that this study was performed during postmortem examination, these observations can be useful to develop criteria, materials and surgical procedures adapted to fetal and neonatal airways as well as for the purposes of early diagnosis and management of laryngotracheal malformations. [source] Assessment of bronchial wall thickness and lumen diameter in human adults using multi-detector computed tomography: comparison with theoretical modelsJOURNAL OF ANATOMY, Issue 5 2007M. Montaudon Abstract A thickened bronchial wall is the morphological substratum of most diseases of the airway. Theoretical and clinical models of bronchial morphometry have so far focused on bronchial lumen diameter, and bronchial length and angles, mainly assessed from bronchial casts. However, these models do not provide information on bronchial wall thickness. This paper reports in vivo values of cross-sectional wall area, lumen area, wall thickness and lumen diameter in ten healthy subjects as assessed by multi-detector computed tomography. A validated dedicated software package was used to measure these morphometric parameters up to the 14th bronchial generation, with respect to Weibel's model of bronchial morphometry, and up to the 12th according to Boyden's classification. Measured lumen diameters and homothety ratios were compared with theoretical values obtained from previously published studies, and no difference was found when considering dichotomic division of the bronchial tree. Mean wall area, lumen area, wall thickness and lumen diameter were then provided according to bronchial generation order, and mean homothety ratios were computed for wall area, lumen area and wall thickness as well as equations giving the mean value of each parameter for a given bronchial generation with respect to its value in generation 0 (trachea). Multi-detector computed tomography measurements of bronchial morphometric parameters may help to improve our knowledge of bronchial anatomy in vivo, our understanding of the pathophysiology of bronchial diseases and the evaluation of pharmacological effects on the bronchial wall. [source] Separation between the digestive and the respiratory lumina during the human embryonic period: morphometric study along the tracheo-oesophageal septumJOURNAL OF ANATOMY, Issue 1 2001JOSEP NEBOT-CEGARRA An isolated tracheo-oesophageal fistula could be caused by close proximity of the epithelia of both organs (O'Rahilly & Müller, 1984; Kluth et al. 1987) at certain embryonic stages, the most frequent location being the tracheal bifurcation. Thus the relative position and degree of separation between the digestive and the respiratory tubes throughout their development may be relevant to the origin of this anomaly. The aim of this study was to analyse along the different segments of the tracheo-oesophageal septum (TES) where the closest relationship between both lumina occurred and what degree of separation was present at each segment. Computer imaging techniques were applied on cross sections of a graded series of normal human embryos (Carnegie stages (CS) 13,23). In addition, the differentiation of the primitive TES was also studied (from CS 12) by light microscopy. Between CS 13 and 16 both tubes tended to separate (phase of separation), principally at the proximal segments of the laryngopharyngeal and the tracheo-oesophageal portions of the TES. During this phase the separation between the trachea and oesophagus was wider than between the larynx and pharynx. From CS 17 to CS 23 the digestive and respiratory lumina reached their widest separation at different levels of the laryngopharyngeal portion. Below these levels they tended to come closer together, principally at the proximal segment of the tracheo-oesophageal portion, but also at the distal part of the laryngopharyngeal portion. During this phase of approximation they reached their closest relationship at the proximal (CS 17) and the distal (from CS 18) segments of the tracheo-oesophageal portion. When finally the distal segment of the trachea (which includes the bifurcation) comes closest to the oesophagus, the coats of both organs have already undergone an appreciable differentiation. According to these observations, the origin of the most frequent isolated tracheo-oesophageal fistula at the bifurcation region could not be explained from the normal development of the TES. [source] A comparative study of mammalian tracheal mucous glandsJOURNAL OF ANATOMY, Issue 3 2000H. K. CHOI We have compared the distribution, numbers and volume of mucous glands in the tracheas of 11 mammalian species. No glands were present in the rabbit. The mouse only contained glands at the border between the trachea and larynx. In the rat, glands were commonest in the cephalad third of the trachea, but on average were much scarcer than in the larger species. Between species, there was a significant correlation between airway diameter and gland volume per unit surface area, suggesting that the rate of deposition of inhaled particles may increase in large airways. In the ventral portion of the trachea of about half the species, the glands were concentrated between the cartilaginous rings; in others they were evenly distributed over and between the rings. In most species in which the trachealis muscle attached to the internal surface of the cartilaginous rings, the glands were external to the muscle. In all species in which the muscle attached to the external surface of the cartilaginous rings, the glands were internal to the muscle. In the ox, goat, dog and sheep, the volume of glands per unit tracheal surface area was markedly greater in the ventral than the dorsal aspect of the trachea. The reverse was true of the pig. In humans, gland density in the 2 regions was similar. The frequency of gland openings was determined in the ox, goat, pig, dog and sheep tracheas, and ranged from 0.3 per mm2 in the dorsal portion of the sheep trachea to 1.5 per mm2 in the ventral portion of the ox trachea. For these 5 species, the volume of gland acini per unit luminal surface area varied linearly with the numbers of gland openings, with the volume of individual glands being constant at , 120 nl. [source] The GlideScope Ranger® video laryngoscope can be useful in airway management of entrapped patientsACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 10 2009A. R. NAKSTAD Background: Airway management of entrapped patients is challenging and alternatives to endotracheal intubation with a Macintosh laryngoscope must be considered. In this study, the GlideScope Ranger® video laryngoscope has been evaluated as an alternative to standard laryngoscopy. Methods: Eight anaesthesiologists from a Helicopter Emergency Medical Service intubated the trachea of a Laerdal SimMan® manikin using the studied laryngoscopes in two scenarios: (A) unrestricted access to the manikin in an ambulance and (B) no access from the head end, simulating an entrapped patient. The time used to secure the airway and the scored level of difficulty were the main variables. Results: In scenario A, all anaesthesiologists managed to secure the airway using both techniques within the 60-s time limit. In scenario B, all secured the airway when using the video laryngoscope, while 50% succeeded with endotracheal intubation using the Macintosh laryngoscope. The difference in the success rate was statististically significant (P=0.025). There were no significant differences in the time spent on endotracheal intubation in the two scenarios or between the devices. All stated that the availability of a video laryngsoscope would make drug-facilitated intubation a realistic alternative when access to patients is limited. The lack of visual control when using the Macintosh laryngoscope excludes this technique in real-life settings. Conclusion: This study suggests that the Glidescope Ranger® may be merited in situations requiring endotracheal intubation by an experienced intubator in patient entrapment. Further studies are required to clarify whether performance in patients mimics that in a manikin. [source] Allometry, bilateral asymmetry and sexual differences in the vocal tract of common eiders Somateria mollissima and king eiders S. spectabilisJOURNAL OF AVIAN BIOLOGY, Issue 2 2007Edward H. Miller Intraspecific sexual differences, high variation, and positive allometry of sexually-selected external display structures are common. Many sexually-selected anatomical specializations occur in the avian vocal tract but intraspecific variation and allometry have been investigated little. The tracheal bulla bulla syringealis occurs in males of most duck species. We quantified variation and size-scaling of the bulla, plus sexual differences in size of trachea, bronchi, and vocal muscles, for 62 common eiders Somateria mollissima and 51 king eiders S. spectabilis. Trends were similar in both species. Bullar ossification and definitive size occurred early in life: bullar size did not differ between first-year and older males. Bullar size did not vary more than size of other body parts (CVs of 3.4,7.0% for bullar length and breadth). Bullar size scaled to body size with negative allometry or isometry. Vocal muscles were 10,50% thicker in males than females, a much greater sexual difference than in body size (CVs of 3,6% on linear body-size variables). Vocal muscles were larger on the left side in both sexes and bilateral asymmetry was slightly more pronounced in males. Low variation and a trend towards negative allometry suggest that bullar size is under stabilizing selection; if bullar size affects vocal attributes of voice, then the latter cannot be condition-dependent. We recommend comparative research on vocal communication, vocal individuality and vocal-tract anatomy and function in eiders and other ducks. [source] Combining the EndoFlex® tube with fiberoptic bronchoscopy in difficult intubationACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 7 2009K. SUGIYAMA We applied a combination technique using the EndoFlex® tube with fiberoptic bronchoscopy for a 69-year-old man presenting with limited mouth opening and neck movement. Awake nasotracheal intubation was performed under conscious sedation with propofol and fentanyl. After positioning the tip of the EndoFlex® tube in the oropharynx, the fiberoptic bronchoscope was inserted into the tube until the tip reached the bevel of the tube. Anterior flexion of the distal tip of the EndoFlex® tube facilitated uncomplicated insertion of the tube into the trachea without impingement on the arytenoids. Fiberoptic visualization confirmed that the distal-tip flexing mechanism of the EndoFlex® tube corrected the direction of the tube tip anteriorly, allowing entry into the trachea. We present a case where this technique proved valuable for tracheal intubation in a patient with limitations of mouth opening and neck movement. [source] | ||||||||||||||||||||||||||||||||||||||||