Tracheal Research Articles

TRPV4 Activation during Guinea Pig Airway Smooth Muscle Contraction Promotes Ca2+ and Na+ Influx.

Airway smooth muscle (ASM) contraction is determined by the increase in intracellular Ca2+ concentration ([Ca2+]i) caused by its release from the sarcoplasmic reticulum (SR) or by extracellular Ca2+ influx. Major channels involved in Ca2+ influx in ASM cells are L-type voltage-dependent Ca2+ channels (L-VDCCs) and nonselective cation channels (NSCCs). Transient receptor potential vanilloid 4 (TRPV4) is an NSCC recently studied in ASM. Mechanical stimuli, such as contraction, can activate TRPV4. We investigated the possible activation of TRPV4 by histamine (His)- or carbachol (CCh)-induced contraction in guinea pig ASM. In single myocytes, the TRPV4 agonist (GSK101) evoked an increase in [Ca2+]i, characterized by a slow onset and a plateau phase. The TRPV4 antagonist (GSK219) decreased channel activity by 94%, whereas the Ca2+-free medium abolished the Ca2+ response induced by GSK101. Moreover, GSK101 caused Na+ influx in tracheal myocytes. GSK219 reduced the Ca2+ peak and the Ca2+ plateau triggered by His or CCh. TRPV4 blockade shifted the concentration-response curve relating to His and CCh to the right in tracheal rings and reduced the maximal contraction. Finally, the activation of TRPV4 in single myocytes increased the Ca2+ refilling of the SR. We conclude that contraction of ASM cells after stimulation with His or CCh promotes TRPV4 activation, the subsequent influx of Ca2+ and Na+, and the opening of L-VDCCs. The entry of Ca2+ into ASM cells via TRPV4 and L-VDCCs contributes to optimal smooth muscle contraction.

Enhancing Paddy Rice Preservation in Small-Scale Barns: Comparative Analysis of Hot Air-Drying Techniques and Ventilation Impact on Quality and Energy Efficiency.

This investigation explores the effectiveness of hot air-drying and ambient ventilation techniques in enhancing the storage quality of Khao Dok Mali 105 paddy rice within small-scale barns in Northeast Thailand. Through comprehensive analysis of moisture and temperature dynamics, the research revealed that an optimized main air pipe system significantly reduces moisture content from 25% db to a desirable 16% db, outperforming alternative systems. Spatial assessments within the barn highlighted the importance of placement, showing that front sections achieved lower moisture levels. This underscores the need for uniform moisture distribution and temperature management to prevent quality degradation. Notably, after 84 h of drying, variations in moisture content across different barn locations emphasized the critical role of environmental control. These insights pave the way for advancing grain storage practices, focusing on strategic ventilation and environmental monitoring to ensure rice quality over time. This study not only challenges traditional methods but also offers significant practical implications for optimizing small-scale rice storage, providing a pathway towards sustainable post-harvest processing in resource-constrained environments.

Analysis of tracheal, bronchial, and lung cancer attributable to respiratory system-related risk factors in 204 countries and territories from 1990 to 2019

IntroductionWe analyzed trends in the tracheal, bronchial, and lung (TBL) cancer disease burdens attributable to respiratory system-related risk factors in 204 countries and territories from 1990 to 2019.Material and methodsBased on the results of the 2019 Global Burden of Disease study, we calculated and analyzed the estimated annual percentage changes (EAPCs) in the age-standardized disability-adjusted life year (DALY) rates and death rates of TBL cancer attributable to total and four individual risk factors globally, regionally, and nationally.ResultsFrom 1990 to 2019, the age-standardized DALY rate and death rate of TBL cancer only attributable to ambient particulate matter pollution increased globally, and in all Socio-Demographic Index (SDI) quintiles, except for high SDI quintiles. Among regions, the most significant increases in those attributable to smoking were seen in East Asia, while those attributable to ambient particulate matter pollution and secondhand smoke were observed in Western Sub-Saharan Africa. Among countries, the most significant increases in those attributable to smoking were observed in São Tomé and Príncipe (EAPC = 1.76) and Bulgaria (EAPC = 1.90), those attributable to ambient particulate matter pollution were observed in Equatorial Guinea, those attributable to secondhand smoke were found in Lesotho (EAPC = 2.01) and Lebanon (EAPC = 2.13), and those attributable to household air pollution from solid fuels were seen in Mozambique.ConclusionsThe burden attributable to ambient particulate matter pollution is increasing, especially in regions such as Western Sub-Saharan Africa and East Asia, and countries such as Equatorial Guinea and Bhutan.

Idiopathic Subglottic Tracheal Stenosis

Idiopathic subglottic stenosis is a circular scarred narrowing of the airway at the transition from the cricoid cartilage to the trachea. The stenosis is found radiologically and endoscopically at the level of the cricoid cartilage without involvement of the cricoid or tracheal cartilage itself. The disease practically only affects women between the ages of 20 and 60. The same clinical picture occurs in granulomatosis with polyangiitis and less frequently in other autoimmune diseases, where it requires systemic treatment. The clinical picture usually begins insidiously with coughing and sputum production and leads to dyspnoea and a restricted cough. As the course is insidious and the patients are otherwise healthy, the symptoms are often misinterpreted and the diagnosis is delayed. Treatment consists of local measures, ranging from dilatation and laser surgical resection, sometimes with local application of medication to inhibit the proliferation of new scar tissue, to laryngotracheal resection of varying degrees. The disease is located in the border area between the trachea and larynx and the patients are therefore treated by ENT medicine, pneumology and thoracic surgery.

Preparation of Decellularized Tissue as Dual Cell Carrier Systems: A Step Towards Facilitating Re-epithelization and Cell Encapsulation for Tracheal Reconstruction.

Surgical treatment of tracheal diseases, trauma, and congenital stenosis has shown success through tracheal reconstruction coupled with palliative care. However, challenges in surgical-based tracheal repairs have prompted the exploration of alternative approaches for tracheal replacement. Tissue-based treatments, involving the cultivation of patient cells on a network of extracellular matrix (ECM) from donor tissue, hold promise for restoring tracheal structure and function without eliciting an immune reaction. In this study, we utilized decellularized canine tracheas as tissue models to develop two types of cell carriers: a decellularized scaffold and a hydrogel. Our hypothesis posits that both carriers, containing essential biochemical niches provided by ECM components, facilitate cell attachment without inducing cytotoxicity. Canine tracheas underwent vacuum-assisted decellularization (VAD), and the ECM-rich hydrogel was prepared through peptic digestion of the decellularized trachea. The decellularized canine trachea exhibited a significant reduction in DNA content and major histocompatibility complex class II, while preserving crucial ECM components such as collagen, glycosaminoglycan, laminin, and fibronectin. Scanning electron microscope and fluorescent microscope images revealed a fibrous ECM network on the luminal side of the cell-free trachea, supporting epithelial cell attachment. Moreover, the ECM-rich hydrogel exhibited excellent viability for human mesenchymal stem cells encapsulated for 3 days, indicating the potential of cell-laden hydrogel in promoting the development of cartilage rings of the trachea. This study underscores the versatility of the trachea in producing two distinct cell carriers-decellularized scaffold and hydrogel-both containing the native biochemical niche essential for tracheal tissue engineering applications.

A Case of Idiopathic Tracheal Stenosis Treated with Tracheal Ring Resection

A Case of Idiopathic Tracheal Stenosis Treated with Tracheal Ring Resection

Study on the effect of pressure in humid air dehumidificationournal

In this paper, there are problems such as large energy consumption and complex system in the field of condensation dehumidification. It is found that increasing pressure can strengthen the effect of condensation dehumidification, simplify the system and reduce energy consumption. So this paper simulates the condensation and dehumidification process of humid air in horizontal pipe under positive pressure. The results show that the dehumidification capacity increases by 25%∼30% when the pressure increases by 100kPa on average. The increase of pressure has little effect on the heat transfer coefficient, but the increase of humidity increases the heat transfer coefficient more obvious. When the humidity of wet air increases by 20%, the heat transfer coefficient increases by 18% ∼ 33%. The dehumidification capacity and heat transfer coefficient increase with the increase of pipe diameter and fluid flow rate.

Ventilation characteristics of double-forced air pipe ventilation in comprehensive mechanized excavation face and determination of its optimal parameters

ABSTRACT This study proposes a ventilation and dust control approach using double-forced air pipes at the tunnel excavation face, aiming to optimize the dust control and reduction measures for underground coal mining environment. We designed a physical model in proportion to the 11,139 excavation face in the Zhangji Coal Mine of China Huaihe Energy Holding Group Coal Company. To begin with, CFD numerical simulation was employed to unveil the basic laws of the double-forced air pipe ventilation approach, including airflow characteristics and dust concentrations. The orthogonal experimental method was then adopted to analyze the influence mechanism of installation location and airflow ratio of the double pipes on the dust density around the driver’s operating space. Results suggest that the double-forced air pipe ventilation can efficiently improve the airflow velocity at the excavation face, reaching 5.54 m/s. With the minimum dust density around the driver’s operating space as the optimal parameter standard and combined with the R value, the three factors in the orthogonal experiment can be sorted as: the distance between the forced ventilation pipe at the driver’s side and the excavation face (R = 206.91) > the distance between the forced ventilation pipe at the return air side and the excavation face (R = 171.72) > the airflow ratio of the two pipes (R = 77.52). The optimal combination is that the distance between the ventilation pipe at the driver’s side and the excavation face is 5 m, the distance between the ventilation pipe at the return air side and the excavation face is 5 m, and the airflow ratio of the two pipes is 6:4. In such a case, the dust density around the driver’s operating space is 48.21 mg/m3, achieving an ideal dust control effect.

Effects of G and SH Truncation on the Replication, Virulence, and Immunogenicity of Avian Metapneumovirus.

Four mutants varying the length of the G and SH genes, including a G-truncated mutant (ΔG) and three G/SH-truncated mutants (ΔSH/G-1, ΔSH/G-2, and ΔSH/G-3), were generated via serially passaging the avian metapneumovirus strain SNU21004 into the cell lines Vero E6 and DF-1 and into embryonated chicken eggs. The mutant ΔG particles resembled parental virus particles except for the variance in the density of their surface projections. G and G/SH truncation significantly affected the viral replication in chickens' tracheal ring culture and in infected chickens but not in the Vero E6 cells. In experimentally infected chickens, mutant ΔG resulted in the restriction of viral replication and the attenuation of the virulence. The mutants ΔG and ΔSH/G-1 upregulated three interleukins (IL-6, IL-12, and IL-18) and three interferons (IFNα, IFNβ, and IFNγ) in infected chickens. In addition, the expression levels of innate immunity-related genes such as Mda5, Rig-I, and Lgp2, in BALB/c mice were also upregulated when compared to the parental virus. Immunologically, the mutant ΔG induced a strong, delayed humoral immune response, while the mutant ΔSH/G-1 induced no humoral immune response. Our findings indicate the potential of the mutant ΔG but not the mutant ΔSH/G-1 as a live attenuated vaccine candidate.

Gasoline Engine Inlet Structure Design and Performance Analysis

By creating a three-dimensional model of the intake pipeline, using AVL software to mesh and virtual simulation experiments, using the control variable method, changing the temperature conditions and pressure conditions one by one to observe the flow of the air pipe and the cylinder, and observing the numerical changes of the flow direction coefficient and tumbling flow ratio, the best solution was found. Through the virtual simulation experiment of the 3D model, the influence of external factors such as temperature and pressure on the air flow in the cylinder is obtained. The relationship between the characteristic parameters of the air intake tract was found through AVL numerical simulation, and the established three-dimensional model could accurately obtain the data after testing, which provided theoretical proof for the subsequent optimization scheme. The experimental results show that the tumbling flow ratio is increased as much as possible without changing the flow coefficient and the fuel economy of the engine is improved. But it also affects the flow coefficient, making it go down. Temperature has little effect on the flow in the cylinder. The flow velocity in the cylinder changes significantly under different pressures, and the area of the vortex area increases.

Temporal control in shell-core structured nanofilm for tracheal cartilage regeneration: synergistic optimization of anti-inflammation and chondrogenesis.

Cartilage tissue engineering offers hope for tracheal cartilage defect repair. Establishing an anti-inflammatory microenvironment stands as a prerequisite for successful tracheal cartilage restoration, especially in immunocompetent animals. Hence, scaffolds inducing an anti-inflammatory response before chondrogenesis are crucial for effectively addressing tracheal cartilage defects. Herein, we develop a shell-core structured PLGA@ICA-GT@KGN nanofilm using poly(lactic-co-glycolic acid) (PLGA) and icariin (ICA, an anti-inflammatory drug) as the shell layer and gelatin (GT) and kartogenin (KGN, a chondrogenic factor) as the core via coaxial electrospinning technology. The resultant PLGA@ICA-GT@KGN nanofilm exhibited a characteristic fibrous structure and demonstrated high biocompatibility. Notably, it showcased sustained release characteristics, releasing ICA within the initial 0 to 15 days and gradually releasing KGN between 11 and 29 days. Subsequent in vitro analysis revealed the potent anti-inflammatory capabilities of the released ICA from the shell layer, while the KGN released from the core layer effectively induced chondrogenic differentiation of bone marrow stem cells (BMSCs). Following this, the synthesized PLGA@ICA-GT@KGN nanofilms were loaded with BMSCs and stacked layer by layer, adhering to a 'sandwich model' to form a composite sandwich construct. This construct was then utilized to repair circular tracheal defects in a rabbit model. The sequential release of ICA and KGN facilitated by the PLGA@ICA-GT@KGN nanofilm established an anti-inflammatory microenvironment before initiating chondrogenic induction, leading to effective tracheal cartilage restoration. This study underscores the significance of shell-core structured nanofilms in temporally regulating anti-inflammation and chondrogenesis. This approach offers a novel perspective for addressing tracheal cartilage defects, potentially revolutionizing their treatment methodologies.

Experimental and numerical investigation of a small scale storm sewer geyser

The violent nature of storm sewer geysers has been puzzling researchers worldwide for a very long time. This paper investigates the geyser simulation methodology using a small-scale set-up, where important flow structures such as slugs, eruption patterns, and pressure oscillations are compared with experimental results to test the fidelity of the numerical modelling. In this exercise, a geyser-like process is produced using a continuous insertion of air in the horizontal pipe. The established methodology is used to simulate the hypothesized scenario of a finite trapped air pocket in the relatively longer pipe system. A geyser produced from a finitely trapped air pocket shows a different eruption mechanism compared to those found in previous studies. First, no slug is observed in the horizontal pipe, resulting in continuous air release. Second, the interface continuously atomizes in the vertical pipe, creating a churn-slug flow that produces a large number of small eruptions.

Morphological comparison of the larynx and trachea of Chelonia mydas (Linnaeus, 1758), Caiman yacare (Daudin, 1802) and Caiman latirostris (Daudin, 1802).

The larynx is in the lower respiratory tract and has the function of protecting the airways, controlling, and modulating breathing, assisting the circulatory system, and vocalizing. This study aims to describe the anatomy and histology of the skeleton of the larynx and trachea of the species Chelonia mydas, Caiman yacare and Caiman latirostris. The study was conducted at the Federal University of Espírito Santo (UFES), using nine specimens of Ch. mydas, 20 of Ca. yacare and four of Ca. latirostris. Samples of the larynx and trachea were collected, fixed, and sent for dissection of the structures and subsequent macroscopic analysis. For histology, samples were processed by the routine paraffin embedding method and stained with hematoxylin-eosin and Verhoeff. For the three species, two arytenoid cartilages, a cricoid cartilage, a hyoid apparatus composed of a base and two horns were found. In Ch. mydas, two structures called thyroid wings were observed, not found in crocodilians. The trachea of crocodilians presented incomplete tracheal rings and musculature, while the trachea of Ch. mydas presented complete tracheal rings. Histologically, the entire cartilaginous skeleton of the larynx of the three species, as well as the tracheal rings, are constituted by hyaline cartilage.

ОПРЕДЕЛЕНИЕ СКОРОСТИ ВЫХОДЯЩЕГО ВОЗДУШНОГО ПОТОКА И ДАВЛЕНИЯ В ВОЗДУХОВОДЕ АВТОМАТИЗИРОВАННОЙ СИСТЕМЫ ДЛЯ СНИЖЕНИЯ ТЕПЛОВОГО СТРЕССА КРС

The management of commercial dairy cattle breeding requires optimal maintenance for animals’ genetic potential obtaining. This contributes to high cattle milk production achieving. Microclimate regulation plays a key role at animal’s health and preventing diseases maintaining. The comfortable conditions for animals make it possible their longevity and high milk production creating. Currently, there is the planet’s temperature increasing that affects animals’ negatively, leading to their health and production deterioration. Microclimate control and regulation can be provided with specialized materials and modern equipment helping. Artificial ventilation including supply, exhaust and a control system, minimizes the influence of human factor on indoor microclimate parameters maintaining. Temperature, humidity and ventilation indicators are important for comfortable conditions ensuring. The automated controller contributes to more efficient operation’s system, errors’ risk reducing and regulation’s accuracy increasing. The aim of this study was outgoing airflow velocity calculate methodology developing and automated system’s pipe pressure at cattle thermal stress reducing. Computer designing and data processing programs (Compass-3D and Microsoft Office) were used. This study results allow to determine the air flow rate at the time of duct’s exit from air pipe (0,475 m/s) and pressure changing in duct’s various sections from 34,15 Pa till 17,95 Pa (up to 52,56% of initial pressure). The study is important for animals’ keeping comfortable conditions ensuring and heat stress reducing, that in turn contributes to livestock production and health improving.

Investigation of solar air collectors with concave air duct

In this article study attempts to study the thermal performance of solar air collectors with submersible air ducts and pipes. This study is conducting numerical analysis of the solar collector with pin wings and turbulators to study the effects on the Nusselt number. The paper begins with a numerical analysis of conventional air collectors and compares them with theoretical results. Reynolds numbers range from 2000 to 2500. Next, after the solar collector's performance is evaluated with the bath air with channels, the effects of turbulators of different heights on the Nusselt number are analyzed, followed by the combined effects of pin wings and turbulators. The results are comparable to conventional solar collectors, and suggest that the combined effects of pin wings and turbulators can significantly improve the thermal performance of solar air collectors. The results of this study may contribute to the development of renewable energy-based air conditioning, ventilation and heating systems.

Isolation and characterization of duck viral enteritis (Duck plague) virus from ducks in field outbreaks in Bangladesh

Duck viral enteritis (DVE) also known as duck plague (DP) is a fatal viral disease of ducks globally that causes huge economic losses in the duck industries. The main objectives of the current study were: the isolation of the circulating duck viral enteritis virus (DVEV) from clinical specimens of field outbreaks, molecular identification of the virus and genetic characterization of DVEVThe natural outbreaks of duck plague (DP) were reported between February and June 2018 on three commercial duck farms located at Netrokona, Mymensingh and Nilphamari districts of Bangladesh. A total of 42 dead ducks were collected from the three farms. Postmortem examination of dead ducks was carried out and gross lesions of the visceral organs were recorded.Liver and spleen samples were collected aseptically and 10% viral inoculum was prepared from liver and spleen. Isolation of DVEV was done by injecting viral inoculum into 9-13 days old embryonated duck eggs through the chorioallantoic membrane (CAM) route.Molecular detection of DVEV in liver, spleen and CAM homogenate was performed by PCR targeting 446 bp fragment of DNA polymerase gene of DVEV. Phylogenetic analysis was carried out by comparing the amino acid sequence of field isolatesof DVEV with the amino acid sequence of global isolates of DVEV deposited in the GenBank. Enlargement of the liver and spleen, abdominal haemorrhage, and annular rings of the trachea were seen in the affected ducks which were characteristics gross lesions in DVE.18of 42 samples (42.85%) were found positive for DVEV by PCR assays. Embryos of duck experimentally inoculated with DVEV were found dead at 3-5 days post infection.Degenerated blood vessels of the CAM, dwarfism of the embryos was observed. The phylogenetic study revealed that the DVEV isolates causing disease outbreak in ducks in the current study were 100% similar to the isolates of DVEV thatpreviously reported from Bangladesh, Vietnam and China.

Shining a Light on Hidden Thyroids: A Case Exploring the Potential of Technetium Imaging for Lingual Thyroid Diagnosis

Ectopic thyroid, the presence of thyroid tissue in locations other than the normal anterior neck region between the second and fourth tracheal cartilages, is the most common form of thyroid dysgenesis. A 32-year-old female patient sought medical attention at the Otolaryngology Department with a foreign body sensation in her throat. To ensure an accurate diagnosis, hereby, the authors conducted a comprehensive diagnostic work-up, which included Technetium-99 (Tc-99m) scanning. Remarkably, the scanning results revealed radiotracer uptake in the base of the tongue while indicating an absence of uptake in the thyroid bed. By shedding light on present captivating case, the present report offers valuable insights into the usage of Technetium imaging in diagnosing doubtful Lingual Thyroid (LT) cases.

A Complete Tracheal Cartilage: An Unexpected Difficult Airway in an Adult with Down Syndrome

A Complete Tracheal Cartilage: An Unexpected Difficult Airway in an Adult with Down Syndrome

Implante 3D de copoliamida associada à elastômero termoplástico (PCTPE) para reparação traqueal de coelhos (Oryctolagus cuniculus): estudo preliminar

Abstract Large segmental tracheal defects can pose a serious clinical challenge owing to the lack of suitable substitutes for reconstructive surgery. Polymeric biomaterials are widely used in medicine. However, the implantation of biomaterials triggers a series of biological events, and material biocompatibility is of paramount importance in regenerative medicine. The objective of this study was to evaluate the use of a copolyamide associated with thermoplastic elastomer (PCTPE) in 3D-printed prostheses for repairing partial tracheal defects in rabbits. Sixteen male New Zealand White rabbits were used, and partial tracheal defects were created in the ventral region from the 4th to the 8th tracheal ring. The animals were subdivided into groups (n=4) based on the time of euthanasia, scheduled at seven days (G7), 15 days (G15), 30 days (G30), and 60 days (G60). Histopathological analysis with hematoxylin and eosin staining revealed that the 3D implant of PCTPE exhibited a foreign body reaction, and inflammation persisted for up to 60 days. Histochemistry with picrosirius red revealed a tendency for a greater amount of type I collagen to accumulate in the early stages of inflammation, whereas type III collagen was predominant in later evaluation periods. These findings suggest an exacerbated and inadequate tissue-material interface reaction and perpetuation of the inflammatory process.

Flap of the sternocephalicus muscle in the repair of a partial defect in the trachea of a rabbit (Oryctolagus cuniculus).

The current study aimed at evaluating the repair of a partial defect of the trachea with a muscle flap, an advanced technique that employs combined suture patterns. Sixteen healthy male New Zealand white rabbits were used as an experimental model. A partial defect in the trachea within the ventral region of the fourth to eighth tracheal ring was created. Subsequently, repair was initiated with a flap of the sternocephalicus muscle. The animals were divided into four groups for postoperative evaluation using clinical, tracheoscopic, and histopathological analyses. Each group was separated according to the time of euthanasia, programmed at interval of seven (G7), 15 (G15), 30 (G30), and 60 days (G60). One animal from the G60 group died, whereas the other animals had good surgical recovery without serious changes in the breathing pattern. The major clinical signs observed were stridor and coughing. Tracheoscopy revealed secretions in the tracheal lumen, exuberant granulation, and stenosis. Histopathological analysis showed growth of the ciliary respiratory epithelium at the flap site 30 days after implantation. Partial repair showed satisfactory results owing to the anatomical location of the muscle, adequate vascular support, and structural and physiological maintenance without serious changes in the respiratory system.