Tracheal Surface Research Articles

The Intricate Role of Ecdysis Triggering Hormone Signaling in Insect Development and Reproductive Regulation.

Insect growth is interrupted by molts, during which the insect develops a new exoskeleton. The exoskeleton confers protection and undergoes shedding between each developmental stage through an evolutionarily conserved and ordered sequence of behaviors, collectively referred to as ecdysis. Ecdysis is triggered by Ecdysis triggering hormone (ETH) synthesized and secreted from peripheral Inka cells on the tracheal surface and plays a vital role in the orchestration of ecdysis in insects and possibly in other arthropod species. ETH synthesized by Inka cells then binds to ETH receptor (ETHR) present on the peptidergic neurons in the central nervous system (CNS) to facilitate synthesis of various other neuropeptides involved in ecdysis. The mechanism of ETH function on ecdysis has been well investigated in holometabolous insects such as moths Manduca sexta and Bombyx mori, fruit fly Drosophila melanogaster, the yellow fever mosquito Aedes aegypti and beetle Tribolium castaneum etc. In contrast, very little information is available about the role of ETH in sequential and gradual growth and developmental changes associated with ecdysis in hemimetabolous insects. Recent studies have identified ETH precursors and characterized functional and biochemical features of ETH and ETHR in a hemimetabolous insect, desert locust, Schistocerca gregaria. Recently, the role of ETH in Juvenile hormone (JH) mediated courtship short-term memory (STM) retention and long-term courtship memory regulation and retention have also been investigated in adult male Drosophila. Our review provides a novel synthesis of ETH signaling cascades and responses in various insects triggering diverse functions in adults and juvenile insects including their development and reproductive regulation and might allow researchers to develop sustainable pest management strategies by identifying novel compounds and targets.

Wet adhesive hydrogels to correct malacic trachea (tracheomalacia) A proof of concept

Tracheomalacia (TM) is a condition characterized by a weak tracheal cartilage and/or muscle, resulting in excessive collapse of the airway in the newborns. Current treatments including tracheal reconstruction, tracheoplasty, endo- and extra-luminal stents have limitations. To address these limitations, this work proposes a new strategy by wrapping an adhesive hydrogel patch around a malacic trachea. Through a numerical model, first it was demonstrated that a hydrogel patch with sufficient mechanical and adhesion strength can preserve the trachea's physiological shape. Accordingly, a new hydrogel providing robust adhesionon wet tracheal surfaces was synthesized employing the hydroxyethyl acrylamide (HEAam) and polyethylene glycol methacrylate (PEGDMA) as main polymer network and crosslinker, respectively. Exvivo experiments revealed that the adhesive hydrogel patches can restrain the collapsing of malacic trachea under negative pressure. This study may open the possibility of using an adhesive hydrogel as a new approach in the difficult clinical situation of tracheomalacia.

Antimicrobial Coating: Tracheal Tube Application

Ventilator-associated pneumonia (VAP) is a common and serious nosocomial infection in mechanically ventilated patients, increasing mortality, prolonging the patient length of stay, and increasing costs. In recent years, extensive studies on ventilator-associated pneumonia have shown that tracheal intubation plays an essential role in the pathogenesis of VAP, with the primary mechanism being the rapid colonization of the tracheal intubation surface by microbiota. Antibiotics do not combat microbial airway colonization, and antimicrobial coating materials offer new ideas to solve this problem. This paper reviews the current research progress on the role of endotracheal tube (ET) biofilms in the pathogenesis of VAP and antimicrobial coating materials.

Preparation and characterization of diesel particle filter (DPF) with hierarchical microstructure for catalytic combustion of soot

Mullite whiskers were prepared on the wall of cordierite honeycomb ceramics using the gas-phase growth method. Subsequently, Co/Ce0.75Zr0.25O2 catalyst was loaded on the mullite whiskers to form hierarchical microstructure by the sol-gel technology for catalytic combustion of soot. Scanning electron microscopy, energy dispersive X-ray spectroscopy, Fourier transform-infrared spectroscopy, X-ray diffraction and Transmission electron microscopy were used to characterize the structural morphology and phase compositions. The filtration capability can be improved by mullite whiskers growth on the wall of cordierite honeycomb ceramics, and the microstructural feature is similar to the pseudostratified ciliated epithelium on the tracheal cavity surface (one section of human respiratory system). The Co/Ce0.75Zr0.25O2 catalyst decreased the ignition temperature of soot particles oxidation, and the cycle stability experiment confirmed that Co/CZ@M/C sample has good structural stability and stable catalytic performance. The high-efficiency filtration and the low-temperature catalytic oxidation of soot particles are combined with the hierarchical microstructure of Co/CZ@M/C, which has potential application in the diesel particulate filter (DPF) field.

Recent, Eco-friendly Approach for Controlling Culex pipiens (L.) using Novel Synthesized Cadmium Sulphide Nanoparticles of Ocimum basillicum Extract

Mosquitoes are the key vector for the transmission of serious parasites and pathogens which affect many people worldwide. The massive overuse of synthetic mosquito insecticides had developed resistance in mosquitoes. Therefore, the need for reliable and eco-friendly control techniques became crucial. Nanoparticle fabrication is a cutting-edge and trending method. The green production of cadmium sulphide nanoparticles (CdS NPs) utilizing Ocimum basillicum leaves as a sophisticated and effective strategy against Culex pipiens was demonstrated in this study. CdS nanoparticles are characterized by a series of techniques including UV-Vis spectrophotometry, High-Resolution Transmission Electron Microscope (HRTEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). CdS nanoparticles (CdS NPs) were highly effective against the larvae (3rd instars) of Culex pipiens after 24 hours of treatment. The LC50 of CdS NPs was 0.0113 g/l. Meanwhile, the LC50 of Ocimum basillicum aqueous extract of leaves was 52.36 g/l. There was no mortality in the control group. CdS NPs also increased larval and pupal duration significantly. Furthermore, it had a deleterious impact on pupation and adult emergence rates. Post-treatment imaging using a light microscope and scanning electron microscopy (SEM) results in larvae had deformities and constrictions in the head and thorax area. The abdomen (digestive tract and respiratory canal) was completely deformed, however, the syphon remained unaffected with typical spiracular valves and very minor abnormalities on the tracheal trunk surface and muscle fibre. Conclusion: Overall, this study suggested that the use of Ocimum basillicum leaves extract mediated synthesis of CdS nanoparticles can be used for controlling Culex pipiens. This is the first study to look at the larvicidal potential of CdS NPs synthesized by Ocimum basillicum leaves extract against Culex pipiens and the potential impacts.

Evaluation of the Effectiveness of VEGF Effect on the Regeneration of the Anterior Tracheal Surface in the Early Postoperative Period

Background. Violation of the regeneration of the tracheal wall after undergoing reconstructive surgeries remains an urgent problem of modern surgery. One of the reasons for the violation of the regeneration processes is insufficient blood supply to the organ. Finding new ways to improve blood flow is a promising area of research. Aim. To evaluate the effectiveness of VEGF effect on the regeneration of the anterior tracheal surface in the early postoperative period. Materials and methods. The study included 60 male Wistar rats at the age of 10 months. All animals underwent tracheal reconstructive surgery; the animals were divided into three groups: group 1 – without medicinal film, group 2 – with prolonged-release medicinal film, group 3 – with prolonged-release medicinal film containing VEGF. The sampling of histological material was carried out on days 3, 7 and 21 of the study, using morphometry to determine the thickness of the tracheal wall, the thickness of the postoperative scar, the area of the surgical intervention zone, the area of the vessels, the ratio of the thickness of the postoperative scar to the wall thickness trachea and the ratio of the area of the vessels to the area of the surgical intervention zone. Results . It was revealed that when exposed to a long-acting medicinal film containing VEGF, significant histological changes occurred on day 7 of the study. In groups 1 and 2, healing occurred by day 21 and was accompanied by defects of the mucous membrane and cartilage. On day 7 in group 3, there was a complete epithelialization of the tracheal wall, an increase in the number of newly formed vessels and glands in the area of surgical intervention. Healing was carried out with a thin postoperative scar without defects in all layers of the tracheal wall. Conclusion . The results obtained indicate the stimulating effect of VEGF on the regeneration of the tracheal wall in the early postoperative period after undergoing reconstructive surgery. The use of VEGF reduces the time of postoperative wound healing and preserves the anatomical structure of the tracheal wall.

Influenza A virus enhances ciliary activity and mucociliary clearance via TLR3 in airway epithelium

BackgroundViral respiratory tract infections, such as influenza A virus (IAV), are common and life-threatening illnesses worldwide. The mechanisms by which viruses are removed from the respiratory tract are indispensable for airway host defense. Mucociliary clearance is an airway defense mechanism that removes pathogens from the respiratory tract. The coordination and modulation of the ciliary beating of airway epithelial cells play key roles in maintaining effective mucociliary clearance. However, the impact of respiratory virus infection on ciliary activity and mucociliary clearance remains unclear.MethodsTracheal samples were taken from wild-type (WT) and Toll-like receptor 3 (TLR3)-knockout (KO) mice. Transient organ culture of murine trachea was performed in the presence or absence of IAV, polyI:C, a synthetic TLR3 ligand, and/or reagents. Subsequently, cilia-driven flow and ciliary motility were analyzed. To evaluate cilia-driven flow, red fluorescent beads were loaded into culture media and movements of the beads onto the tracheal surface were observed using a fluorescence microscope. To evaluate ciliary motility, cilia tips were labeled with Indian ink diluted with culture medium. The motility of ink-labeled cilia tips was recorded by high-speed cameras.ResultsShort-term IAV infection significantly increased cilia-driven flow and ciliary beat frequency (CBF) compared with the control level in WT culture. Whereas IAV infection did not elicit any increases of cilia-driven flow and CBF in TLR3-KO culture, indicating that TLR3 was essential to elicit an increase of cilia-driven flow and CBF in response to IAV infection. TLR3 activation by polyI:C readily induced adenosine triphosphate (ATP) release from the trachea and increases of cilia-driven flow and CBF in WT culture, but not in TLR3-KO culture. Moreover, blockade of purinergic P2 receptors (P2Rs) signaling using P2R antagonist, suramin, suppressed polyI:C-mediated increases of cilia-driven flow and CBF, indicating that TLR3-mediated ciliary activation depended on released extracellular ATP and the autocrine ATP-P2R loop.ConclusionsIAV infection readily increases ciliary activity and cilia-driven flow via TLR3 activation in the airway epithelium, thereby hastening mucociliary clearance and “sweeping” viruses from the airway as an initial host defense response. Mechanically, extracellular ATP release in response to TLR3 activation promotes ciliary activity through autocrine ATP-P2R loop.

Iodine 131 in the treatment of large goiters

The treatment of large, complicated goiters with iodine 131 constitutes an interesting alternative to surgery. It is minimally invasive, safe, and effective in most cases, and is particularly valuable in elderly, fragile patients with multiple co-morbidities. Also, it does not preclude the possibility of surgery, should it become a necessary alternative, for whatever reason in the future. The precise pre-treatment evaluation includes thyroid scintigraphy, calculation of thyroid volume and tracheal surface measurement. Patients who are most at risk of acute complications (very small cross sectional tracheal area, underlying respiratory pathology, and hyperthyroidism) should be managed during hospitalization for possible respiratory distress, or rhythm disturbances induced by hormone release. The choice of the iodine 131 activity depends on individual routine practice, either standardized or modulated by thyroid mass. Administration may be repeated depending on the effect obtained and the cumulative dose. Efficacy in terms of volume reduction is practically constant at an early stage. Its effectiveness is difficult to predict, often less in the case of large size goiters. It can be improved by increasing iodine fixation, for example, using synthetic antithyroid drugs. Permanent hypothyroidism is the most frequent and minor complication of the treatment. It involves biological monitoring in order to introduce hormone replacement therapy to avoid thyroid growth stimulation and negate the benefits of radioiodine treatment.

Potential physical effects of suspended fine sediment on lotic macroinvertebrates

This study investigates the potential for physical damage caused by suspended fine sediment on gills of three macroinvertebrate species, Hydropsyche siltalai, Ephemera danica and Ecdyonurus venosus. Macroinvertebrate cadavers were exposed to three suspended sediment concentrations (control 3.5, low 83.7 and high 404.0 mg l−1) at two velocities (low 0.19 m s−1 and high 0.37 m s−1), for 6 h in a recirculating flume. Tracheal gill surfaces were subsequently examined for evidence of physical damage using scanning electron microscopy (SEM) images. Physical damage predominantly consisted of fine sediment coverage of gill surfaces, appearing as a deposited layer of sediment obscuring and potentially clogging the gill. For E. venosus, suspended sediment concentration influenced gill cover, but velocity had no significant effect. Coverage of H. siltalai gill surfaces increased significantly between low and high sediment concentrations but only at the higher flow velocity. Gill coverage of E. danica did not differ across any sediment concentration. The results were consistent with reported species sensitivities to fine sediment, despite the use of cadavers. However, we found limited evidence of physical abrasion as a direct physical effect of fine sediment under the experimental conditions used.

A Novel AAV-mediated Gene Delivery System Corrects CFTR Function in Pigs.

Cystic fibrosis is an autosomal-recessive disease that is caused by a mutant CFTR (cystic fibrosis transmembrane conductance regulator) gene and is characterized by chronic bacterial lung infections and inflammation. Complementation with functional CFTR normalizes anion transport across the airway surface. Adeno-associated virus (AAV) is a useful vector for gene therapy because of its low immunogenicity and ability to persist for months to years. However, because its episomal expression may decrease after cell division, readministration of the AAV vector may be required. To overcome this, we designed an integrating AAV-based CFTR-expressing vector, termed piggyBac (PB)/AAV, carrying CFTR flanked by the terminal repeats of the piggyBac transposon. With codelivery of the piggyBac transposase, PB/AAV can integrate into the host genome. Because of the packaging constraints of AAV, careful consideration was required to ensure that the vector would package and express its CFTR cDNA cargo. In this short-term study, PB/AAV-CFTR was aerosolized to the airways of CF pigs in the absence of the transposase. Two weeks later, transepithelial Cl- current was restored in freshly excised tracheal and bronchial tissue. Additionally, we observed an increase in tracheal airway surface liquid pH and bacterial killing in comparison with untreated CF pigs. Airway surface liquid from primary airway cells cultured from treated CF pigs exhibited increased pH correlating with decreased viscosity. Together, these results show that complementing CFTR in CF pigs with PB/AAV rescues the anion transport defect in a large-animal CF model. Delivery of this integrating viral vector system to airway progenitor cells could lead to persistent, life-long expression in vivo.

Live-pig-airway surface imaging and whole-pig CT at the Australian Synchrotron Imaging and Medical Beamline.

The Australian Synchrotron Imaging and Medical Beamline (IMBL) was designed to be the world's widest synchrotron X-ray beam, partly to enable clinical imaging and therapeutic applications for humans, as well as for imaging large-animal models. Our group is currently interested in imaging the airways of newly developed cystic fibrosis (CF) animal models that display human-like lung disease, such as the CF pig. One key outcome measure for assessing the effectiveness of CF airway therapies is the ability of the lung to clear inhaled particulates by mucociliary transit (MCT). This study extends the ex vivo sheep and pig tracheal-tissue studies previously performed by the authors at the IMBL. In the present study, attempts were made to determine whether the design of the IMBL is suitable for imaging tracheal MCT in live pigs. The movement of 200 µm-diameter high-refractive-index (HRI) glass-bead marker particles deposited onto the tracheal airway surface of eight live piglets was tracked and quantified and the MCT response to aerosol delivery was examined. A high-resolution computed tomographic (CT) whole-animal post-mortem scan of one pig was also performed to verify the large sample CT capabilities of the IMBL. MCT tracking particles were visible in all animals, and the automated MCT tracking algorithms used were able to identify and track many particles, but accuracy was reduced when particles moved faster than ∼6 mm min-1 (50pixels between exposures), or when the particles touched or overlapped. Renderings were successfully made from the CT data set. Technical issues prevented use of reliable shuttering and hence radiation doses were variable. Since dose must be carefully controlled in future studies, estimates of the minimum achievable radiation doses using this experiment design are shown. In summary, this study demonstrated the suitability of the IMBL for large-animal tracheal MCT imaging, and for whole-animal CT.

Quantitative Assessment of Regional Dynamic Airway Collapse in Neonates via Retrospectively Respiratory-Gated 1 H Ultrashort Echo Time MRI.

Neonatal dynamic tracheal collapse (tracheomalacia, TM) is a common and serious comorbidity in infants, particularly those with chronic lung disease of prematurity (bronchopulmonary dysplasia, BPD) or congenital airway or lung-related conditions such as congenital diaphragmatic hernia (CDH), but the underlying pathology, impact on clinical outcomes, and response to therapy are not well understood. There is a pressing clinical need for an accurate, objective, and safe assessment of neonatal TM. To use retrospectively respiratory-gated ultrashort echo-time (UTE) MRI to noninvasively analyze moving tracheal anatomy for regional, quantitative evaluation of dynamic airway collapse in quiet-breathing, nonsedated neonates. Prospective. Twenty-seven neonatal subjects with varying respiratory morbidities (control, BPD, CDH, abnormal polysomnogram). High-resolution 3D radial UTE MRI (0.7 mm isotropic) on 1.5T scanner sited in the neonatal intensive care unit. Images were retrospectively respiratory-gated using the motion-modulated time-course of the k-space center. Tracheal surfaces were generated from segmentations of end-expiration/inspiration images and analyzed geometrically along the tracheal length to calculate percent-change in luminal cross-sectional area (A % ) and ratio of minor-to-major diameters at end-expiration (r D,exp ). Geometric results were compared to clinically available bronchoscopic findings (n = 14). Two-sample t-test. Maximum A % significantly identified subjects with/without a bronchoscopic TM diagnosis (with: 46.9 ± 10.0%; without: 27.0 ± 5.8%; P < 0.001), as did minimum r D,exp (with: 0.346 ± 0.146; without: 0.671 ± 0.218; P = 0.008). Subjects with severe BPD exhibited a far larger range of minimum r D,exp than subjects with mild/moderate BPD or controls (0.631 ± 0.222, 0.782 ± 0.075, and 0.776 ± 0.030, respectively), while minimum r D,exp was reduced in CDH subjects (0.331 ± 0.171) compared with controls (P < 0.001). Respiratory-gated UTE MRI can quantitatively and safely evaluate neonatal dynamic tracheal collapse, as validated with the clinical standard of bronchoscopy, without requiring invasive procedures, anesthesia, or ionizing radiation. 2 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2019;49:659-667.

Entrapment of a laryngotracheal topical anesthesia kit during tracheobronchial foreign body removal: a case report

BackgroundIn order to reduce the irritation of the airway during tracheobronchial foreign body (TFB) removal, tracheal surface anesthesia is usually performed using a laryngotracheal topical anesthesia (LTA) kit (LTA20, Highgreen Medical Technology Company, China), but difficulty in withdrawing the LTA kit is rarely reported. We present a case of a difficulty to withdraw the LTA kit due to its entrapment by the movement of a TFB.Case presentationA 1-year-old girl was undergoing TFB removal. After the surgeon completed the tracheal surface anesthesia, the girl suddenly suffered from bucking, leading to the dislodgment of the TFB to the subglottic region, complicating the withdrawal of the LTA applicator. At the same time, the girl’s oxygen saturation (SpO2) decreased to 91% and her heart rate dropped from 150 to 100 bpm. Atropine and succinylcholine were administered intravenously immediately, then the surgeon tried to free the TFB by pushing it back into the trachea, after which the LTA applicator was easily withdrawn, and TFB was removed successfully. The girl was discharged from hospital without any complications 2 days later.ConclusionThis case report draws our attention to a significant anesthetic clinical consideration during the application of topical anesthesia on the trachea for TFB removal. The possibility of coughing or bucking can lead to migration of the TFB with subsequent airway obstruction, so the depth of anesthesia must be sufficient to prevent harmful reflexes. Also, strong teamwork and good communication are paramount to avoid serious complications.

The mucus bundles responsible for airway cleaning are retained in cystic fibrosis and by cholinergic stimulation.

The beneficial effect of anticholinergic therapy for chronic lung diseases such as chronic obstructive pulmonary disease (COPD) is well documented, although cholinergic stimulation paradoxically inhibits liquid absorption, increases ciliary beat frequency and increases airway surface liquid transport.Using pig tracheobronchial explants, we quantified basal mucus transport before as well as after incubation with the clinically used antimuscarinic compound ipratropium bromide (Atrovent) and stimulation with acetylcholine.As expected, surface liquid transport was increased by acetylcholine and carbachol. In contrast, the mucus bundles secreted from the submucosal glands normally transported on the cilia were stopped from moving by acetylcholine, an effect inhibited by ipratropium bromide. Interestingly, in pigs lacking a functional cystic fibrosis (CF) transmembrane conductance regulator (CFTR) channel, the mucus bundles were almost immobile. As in wild-type pigs, CF surface liquid transport increased after carbachol stimulation. The stagnant CF mucus bundles were trapped on the tracheal surface attached to the surface goblet cells. Pseudomonas aeruginosa bacteria were moved by the mucus bundles in wild-type but not CF pigs.Acetylcholine thus uncouples airway surface liquid transport from transport of the surface mucus bundles as the bundles are dynamically inhibited by acetylcholine and the CFTR channel, explaining initiation of CF and COPD, and opening novel therapeutic windows.

Effect of Endotracheal Tube with Subglottic Suction Port vs Standard Endotracheal Tube on Incidence of Ventilator Associated Pneumonia in Patients of Organo-Phosphate Poisoning

Ventilator associated pneumonia is a hospital acquired infection that develops after 48 hours or more after a patient is intubated with an endotracheal or tracheostomy tube and is put on mechanical ventilation [1]. Ventilator associated pneumonia is most common nosocomial infection in ICU and associated with prolonged hospitalization, increased health care costs, and high attributable mortality. Intubation independently increases the risk of developing nosocomial pneumonia atleast seven fold with a peak incidence occurring around day five of ventilation [2]. Tracheal intubation thwarts cough reflex, compromises mucociliary clearance, injures tracheal epithelial surface, provides a direct conduct for rapid access of bacteria from upper into lower respiratory tract and allows formation of biofilm on Endotracheal tube surface. The combination of these factors puts mechanically ventilated patient at great risk of developing VAP. Aims and Objectives: To study incidence of VAP in ET tube with subglottic suction port versus standard ET tube in cases of O.P poisoning in J.J.M Medical college, Davangere from December 2015-June 2017. Material and Methods: A prospective observational case control study of 80 patients admitted to Red Zone/ICU of J.J.M. Medical College, Davangere. Results: Patients who have presented with Organophosphorous poisoning between the age group of 18 to 60 years who require ventilator support, intubated with standard ET tube and another sub set of patients intubated with ET tube with subglottic suction port were analysed. In this study we found that distribution of various organisms with regards to sputum culture in both groups were pseudomonas being maximum and proteus was found in minimum percentage. When subglottic suction port is used we observed improved patients were 70% and deaths were 30%. When subglottic suction port is not used we observed improved were 55% and death were 45%. Conclusion: VAP is common in patients who are intubated in ICU, which has higher morbidity and mortality among these patients. In our study we observed that atropine usually decreases secretions, but here in this study patient population who were admitted developed secretions instead of adequate atropine dosage and also developed VAP. Use of ET tube with Subglottic suction drainage may prevent VAP in cases of Organo Phosphorous poisoning and also improves patient outcomes.

РАСТРОВАЯ КРИОЭЛЕКТРОННАЯ МИКРОСКОПИЯ ЛЕГКИХ У КРЫС ПРИ ХОЛОДОВОМ ВОЗДЕЙСТВИИ

The aim of research is to investigate important structures in vivo of mucociliary conveyor of respiratory and airway parts of the lung of intact rats against general cooling by the method of scanning cryoelectron microscopy without fixation and dehydration. The rats (male) in an amount of 40 pieces were exposed to general cooling during 14 days for 3 hours per day at the temperature of -15ºC. Frozen in liquid nitrogen tracheal samples were placed on a freezing Pelzer table (-30ºC) of the consoles Deben Coolstage of scanning electron microscope Hitachi S-3400. The study was conducted at low vacuum (80Pa) using backscattered electrons detector (BSECOMP). It was found out that the epithelial lining of the trachea of rats is covered with a liquid layer consisting of viscous gel and aqueous phases masking ciliary epithelial cells. Mucous secretion of the bronchi is presented by single plates with mucus cellular elements. On the alveolar surface in the monolayer of surfactant there were discovered globular clusters of lattice surfactant. With total cooling on the surface of epithelial layer the amount of bronchial secretions increases, the structure of the mucociliary apparatus changes and tracheal mucosa surface becomes wavy and there are sometimes marked accumulations of mucus. In the epithelial lining there are identified areas with the predominance of ciliated epithelium goblet cells lacking microvilli. The secretory activity of goblet cells and type 2 alveolocytes of respiratory department is accompanied by an increased release of secretion causing a disturbance of mucociliary transport.

Lentiviral-mediated phenotypic correction of cystic fibrosis pigs.

Cystic Fibrosis (CF) is an autosomal recessive disease caused by mutations in CF transmembrane conductance regulator (CFTR), resulting in defective anion transport. Regardless of the disease-causing mutation, gene therapy is a strategy to restore anion transport to airway epithelia. Indeed, viral vector-delivered CFTR can complement the anion channel defect. In this proof-of-principle study, functional in vivo CFTR channel activity was restored in the airways of CF pigs using a feline immunodeficiency virus-based (FIV-based) lentiviral vector pseudotyped with the GP64 envelope. Three newborn CF pigs received aerosolized FIV-CFTR to the nose and lung. Two weeks after viral vector delivery, epithelial tissues were analyzed for functional correction. In freshly excised tracheal and bronchus tissues and cultured ethmoid sinus cells, we observed a significant increase in transepithelial cAMP-stimulated current, evidence of functional CFTR. In addition, we observed increases in tracheal airway surface liquid pH and bacterial killing in CFTR vector-treated animals. Together, these data provide the first evidence to our knowledge that lentiviral delivery of CFTR can partially correct the anion channel defect in a large-animal CF model and validate a translational strategy to treat or prevent CF lung disease.

Temporal and spatial expression of Muc2 and Muc5ac mucins during rat respiratory and digestive tracts development

Secreted mucins constitute a crucial part of the gel that protects respiratory and digestive epithelia, being MUC2/Muc2 the predominant gel-forming mucin of the intestine while MUC5AC/Muc5ac is one of the gel-forming mucins most expressed at the airways. In this study, we have analyzed Muc2 and Muc5ac during rat development by using immunohistochemistry, Western blotting and RT-PCR. We demonstrated that rat Muc2 was expressed in fetal intestinal goblet cells of surface epithelium of villi and developing Lieberkühn crypts. In neonates and adults, Muc2 was expressed at luminal goblet cells of small and large intestine and at gastric mucous and glandular cells. Muc5ac protein was observed in embryonic gastric and lung samples; expression increased during development and postnatal and adult life. After birth, a low reaction was detected at the tracheal surface epithelium and glands, which increased in adults.

Myosin Id is required for planar cell polarity in ciliated tracheal and ependymal epithelial cells.

In wild type (WT) tracheal epithelial cells, ciliary basal bodies are oriented such that all cilia on the cell surface beat in the same upward direction. This precise alignment of basal bodies and, as a result, the ciliary axoneme, is termed rotational planar cell polarity (PCP). Rotational PCP in the multi-ciliated epithelial cells of the trachea is perturbed in rats lacking myosin Id (Myo1d). Myo1d is localized in the F-actin and basal body rich subapical cortex of the ciliated tracheal epithelial cell. Scanning and transmission electron microscopy of Myo1d knock out (KO) trachea revealed that the unidirectional bending pattern is disrupted. Instead, cilia splay out in a disordered, often radial pattern. Measurement of the alignment axis of the central pair axonemal microtubules was much more variable in the KO, another indicator that rotational PCP is perturbed. The asymmetric localization of the PCP core protein Vangl1 is lost. Both the velocity and linearity of cilia-driven movement of beads above the tracheal mucosal surface was impaired in the Myo1d KO. Multi-ciliated brain ependymal epithelial cells exhibit a second form of PCP termed translational PCP in which basal bodies and attached cilia are clustered at the anterior side of the cell. The precise asymmetric clustering of cilia is disrupted in the ependymal cells of the Myo1d KO rat. While basal body clustering is maintained, left-right positioning of the clusters is lost.

Molecular analysis of the caecal and tracheal microbiome of heat-stressed broilers supplemented with prebiotic and probiotic

The gastrointestinal tract commensal microbiome is important for host nutrition, health and immunity. Little information is available regarding the role of these commensals at other mucosal surfaces in poultry. Tracheal mucosal surfaces offer sites for first-line health and immunity promotion in broilers, especially under stress-related conditions. The present study is aimed at elucidating the effects of feed supplementations with mannanoligosaccharides (MOS) prebiotic and a probiotic mixture (PM) on the caecal and tracheal microbiome of broilers kept under chronic heat stress (HS; 35 ± 2°C). Day-old chickens were randomly divided into five treatment groups: thermoneutral control (TN-CONT), HS-CONT, HS-MOS, HS-PM and HS synbiotic (fed MOS and PM). Caecal digesta and tracheal swabs were collected at day 42 and subjected to DNA extraction, followed by polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE) and pyrosequencing. The PCR-DGGE dendrograms revealed significant (49.5% similarity coefficients) differences between caecal and tracheal microbiome. Tracheal microbiome pyrosequencing revealed 9 phyla, 17 classes, 34 orders, 68 families and 125 genera, while 11 phyla, 19 classes, 34 orders, 85 families and 165 genera were identified in caeca. An unweighted UniFrac distance metric revealed a distinct clustering pattern (analysis of similarities, P = 0.007) between caecal and tracheal microbiome. Lactobacillus was the most abundant genus in trachea and caeca and was more abundant in caeca and trachea of HS groups compared with the TN-CONT group. Distinct bacterial clades occupied the caecal and tracheal microbiomes, although some bacterial groups overlapped, demonstrating a core microbiome dominated by Lactobacillus. No positive effects of supplementations were observed on abundance of probiotic bacteria.