Laryngeal Mucosa
Larynx
Laryngeal Nerves
Laryngitis
Laryngeal Diseases
Laryngeal Muscles
Reflex
Intestinal Mucosa
Gastric Mucosa
Mouth Mucosa
Mucosal pressures from the cuffed oropharyngeal airway vs the laryngeal mask airway. (1/73)
We tested the hypothesis that pressures exerted on the pharyngeal mucosa by the laryngeal mask airway (LMA) and cuffed oropharyngeal airway (COPA) differ, in 20 male and 20 female adult patients. Microchip pressure sensors were attached to the LMA and COPA at four similar anatomical locations (base of the tongue, lateral pharynx, posterior pharynx and distal oropharynx) and two dissimilar locations (LMA, piriform fossa and hypopharynx; COPA, middle of the tongue and proximal oropharynx). Cuff volume was adjusted until oropharyngeal leak pressure (OLP) was 10 cm H2O and mucosal pressures were recorded. This was repeated at an OLP of 15 cm H2O and at maximal OLP. Overall mucosal pressures were higher for the COPA than the LMA at 10 cm H2O (17 vs 3 cm H2O; P < 0.0001), at 15 cm H2O (21 vs 6 cm H2O; P < 0.0001) and at maximal OLP (26 vs 9 cm H2O; P < 0.0001). Mucosal pressures were always higher for the COPA at the base of the tongue, posterior pharynx and lateral pharynx, but were similar in the distal oropharynx. Maximal OLP was higher for the LMA than the COPA (27 (95% confidence intervals 25-29) vs 16 (12-19) cm H2O; P < 0.0001). We conclude that pressures acting on the mucosa were higher with the COPA compared with the LMA. (+info)Chromosome instability as an indicator of malignant progression in laryngeal mucosa. (2/73)
PURPOSE: Routine histologic examination cannot predict whether premalignant laryngeal lesions will progress toward invasive growth. The acquisition of changes in chromosome constitution has been suggested to be essential for driving tumor progression by enhancing mutagenic mechanisms. The aim of the present study was to determine whether chromosomal changes occur in the subsequent stages of early laryngeal carcinogenesis and, if so, whether these changes can be of prognostic value. MATERIALS AND METHODS: Numerical aberrations for chromosomes 1 and 7 were detected in tissue sections from archival material using an improved in situ hybridization protocol. In total, eight benign laryngeal lesions, 37 premalignant laryngeal lesions, and 16 specimens containing histologically normal epithelia adjacent to laryngeal squamous cell carcinomas were studied. Both the histologic and the cytogenetic classifications were correlated with progression to laryngeal cancer. RESULTS: No evidence for chromosome alterations was obtained in the control group, nor in histologically normal epithelia adjacent to laryngeal squamous cell carcinomas, nor in all but one hyperplastic lesion (n = 11). In contrast, 14 of 15 dysplastic lesions and nine of 11 carcinomas-in-situ contained numerical chromosomal aberrations. Tetrasomy was present in the majority of the dysplastic lesions. An unstable chromosome content (indicated by the presence of chromosome imbalances and/or polyploidization) in the premalignant lesion strongly predicted its malignant progression. CONCLUSION: Our results show that laryngeal tumor development involves chromosome tetraploidization. The further change from a stable to an unstable chromosome constitution is of importance for malignant progression. (+info)Calbindin D28k-immunoreactive afferent nerve endings in the laryngeal mucosa. (3/73)
The distribution of the calbindin D28k in the laryngeal sensory structures was studied by immunohistochemistry, immunoelectronmicroscopy, and double immunofluorescence with calretinin-immunoreactivity. Moreover, origin of the nerve endings were observed using retrograde tracer, fast blue. Immunoreactivity for calbindin D28k was found in the various types of nerve endings in the larynx, namely, laminar nerve endings, nerve endings associated with the taste buds, intraepithelial nerve endings, and endocrine cells. The laminar endings with calbindin D28k-immunoreactivity were observed in the subepithelial connective tissue. In some endings, terminals were expanded. The laminar endings were also observed in the perichondrium of the epiglottic cartilage. In the epiglottic and arytenoid epithelia, thick nerve fibers with calbindin D28k-immunoreactivity ascending to taste buds and intragemmal nerve fibers were also observed. Within the epithelial layer, intraepithelial free nerve endings with calbindin D28k-immunoreactivity were observed. Furthermore, diffuse endocrine cells were observed within the laryngeal epithelium. By immunoelectron microscopy, immunoreaction products in the endings mentioned above were localized in the cytoplasm of the axon terminals and nerve fibers which contained with numerous mitochondria. Out of the 100 laminar endings, 18 endings were immunopositive for both calbindin D28k and calretinin, 33 were positive for calbindin D28k but negative for calretinin, and 49 were positive for only calretinin in the double immunofluorescence microscopy. The nerve fibers associated with the taste buds and the free nerve endings, which immunostained for calbindin D28k, were not stained with antibody against calretinin. After injection of the fast blue in the laryngeal mucosa, fast blue-labeled cells were mainly observed in the nodose ganglia. Of the total number of labeled cell in the nodose and dorsal root ganglia at the level C1 to Th2, 65.1% occurred in nodose ganglia (572/879, n = 6). In the nodose ganglia, 79.7% of labeled cells (456/572) were immunoreacted for calbindin D28k. The distribution of calbindin D28k-immunoreactivity may be differnt from that of calretinin. It is suggested that calbindin D28k have regulatory role on intracellular calcium concentration in the laryngeal sensory corpuscles. (+info)The influence of cuff volume and anatomic location on pharyngeal, esophageal, and tracheal mucosal pressures with the esophageal tracheal combitube. (4/73)
BACKGROUND: The authors determined the influence of cuff volume and anatomic location on pharyngeal, esophageal, and tracheal mucosal pressures for the esophageal tracheal combitube. METHODS: Twenty fresh cadavers were studied. Microchip sensors were attached to the anterior, lateral, and posterior surfaces of the distal and proximal cuffs of the small adult esophageal tracheal combitube. Mucosal pressure for the proximal cuff in the pharynx was measured at 0- to 100-ml cuff volume in 10-ml increments, and for the distal cuff in the esophagus and trachea were measured at 0- to 20-ml cuff volume in 2-ml increments. The proximal cuff volume to form an oropharyngeal seal of 30 cm H2O was determined. In addition, mucosal pressures for the proximal cuff in the pharynx were measured in four awake volunteers with topical anesthesia. RESULTS: There was an increase in mucosal pressure in the trachea, esophagus, and pharynx at all cuff locations with increasing volume (all: P < 0.001). Pharyngeal mucosal pressures were highest posteriorly (50-ml cuff volume: 99 +/- 62 cm H2O; 100-ml cuff volume: 255 +/- 161 cm H2O). Esophageal mucosal pressures were highest posteriorly (10-ml cuff volume: 108 +/- 55 cm H2O; 20-ml cuff volume: 269 +/- 133 cm H2O). Tracheal mucosal pressures were highest anteriorly (10-ml cuff volume: 98 +/- 53 cm H2O; 20-ml cuff volume: 236 +/- 139 cm H2O). The proximal cuff volume to obtain an oropharyngeal seal of 30 cm H2O was 47 +/- 12 ml. Pharyngeal mucosal pressures were similar for cadavers and awake volunteers. CONCLUSION: We conclude that mucosal pressures for the esophageal tracheal combitube increase with cuff volume, are highest where the cuff is adjacent to rigid anatomic structures, and potentially exceed mucosal perfusion pressure even when cuff volumes are limited to achieving an oropharyngeal seal of 30 cm H2O. (+info)Transfection efficiency and toxicity of polyethylenimine in differentiated Calu-3 and nondifferentiated COS-1 cell cultures. (5/73)
In the present study, we evaluated polyethylenimine (PEI) of different molecular weights (MWs) as a DNA complexing agent for its efficiency in transfecting nondifferentiated COS-1 (green monkey fibroblasts) and well-differentiated human submucosal airway epithelial cells (Calu-3). Studying the effect of particle size, zeta potential, presence of serum proteins or chloroquine, it appeared that transfection efficiency depends on the experimental conditions and not on the MW of the PEI used. Comparing transfection efficiencies in both cell lines, we found that PEI was 3 orders of magnitude more effective in COS-1 than in Calu-3 cells, because Calu-3 cells are differentiated and secrete mucins, which impose an additional barrier to gene delivery. Transfection efficiency was strongly correlated to PEI cytotoxicity. Also, some evidence for PEI-induced apoptosis in both cell lines was found. In conclusion, our results indicate that PEI is a useful vector for nonviral transfection in undifferentiated cell lines. However, results from studies in differentiated bronchial epithelial cells suggest that PEI has yet to be optimized for successful gene therapy of cystic fibrosis (CF). (+info)Requirement of STAT3 activation for differentiation of mucosal stratified squamous epithelium. (6/73)
STAT3, a member of the signal transducers and activators of transcription (STAT) family, has been shown to play a key role in promoting proliferation, differentiation, or cell cycle progression, depending on cell type. A number of signaling pathways are altered in laryngeal papillomas, benign tumors induced by human papillomavirus 6/11. Papillomas overexpress the epidermal growth factor receptor and display enhanced MAP kinase and PI-3-kinase activity. They also show reduced activation of Akt and reduced levels of tyrosine-phosphorylated STAT3, due to overexpression of the tumor suppressor, PTEN. As papillomas show abnormalities in terminal differentiation, we examined the potential role of STAT3 in regulating epithelial differentiation. Laryngeal epithelial cells were suspended in supplemented serum-free medium. Differentiation was measured by Western blot analysis of keratin 13. Normal laryngeal epithelial cells were transfected with a constitutively active STAT3 or a dominant negative STAT3. Cells were transferred to suspension culture 24 h after transfection. Increased expression of keratin 13 was accompanied by the activation of STAT3 when differentiation was induced, and expression of a constitutively active STAT3 (STAT3C) enhanced the expression of keratin 13. In contrast, expression of a dominant negative STAT3 (Y705F) inhibited the expression of keratin 13. We conclude that activation of STAT3 is required for the differentiation of normal human stratified squamous epithelium. (+info)Differential major histocompatibility complex class II locus expression on human laryngeal epithelium. (7/73)
The survival of a laryngeal allograft will be dependent on the immunological composition of the donor larynx and, in particular, on the expression of major histocompatibility complex (MHC) class II antigens on professional and non-professional antigen-presenting cells. Laryngeal and tonsillar biopsies from normal individuals aged 18-78 years were processed and prepared for quantitative, multiple-colour immunofluorescence using mouse antihuman monoclonal antibodies to human leucocyte antigen (HLA)-DR, HLA-DQ and CD45. The laryngeal epithelium expressed HLA-DR locus products at variable levels, but expression of HLA-DQ was virtually absent. Tonsillar epithelial cells expressed HLA-DR at the basal layer only, while HLA-DQ was similarly not expressed. In contrast, both HLA-DR and -DQ locus products were present on lamina propria and intraepithelial leucocytes in both laryngeal and tonsillar mucosae, although at varying levels. The finding that laryngeal epithelial cells express MHC class II antigens has implications for the survival of laryngeal allografts and suggests that they may require significant immunomodulation. In addition, antigen presentation by epithelial cells has been hypothesized to contribute to the immunoregulatory function of mucosal tissues, and the finding that HLA-DQ locus products are only expressed at low levels by laryngeal epithelium raises questions about the repertoire of peptides to which the mucosal immune system can respond. (+info)Non-Hodgkin lymphoma of the larynx: CT and MR imaging findings. (8/73)
BACKGROUND AND PURPOSE: Non-Hodgkin lymphoma (NHL) of the larynx is a rare tumor. The aim of this study was to report the CT and MR features of laryngeal NHL in four patients to determine if there are any features that might be helpful to distinguish NHL from other laryngeal tumors. METHODS: The CT and MR images of four patients with laryngeal NHL were retrospectively reviewed for tumor volume and distribution, appearance, local invasion, and lymphadenopathy. RESULTS: Tumor volume ranged from 4 to 45 mL(3). Tumor was based in the submucosal (2/4 [50%]), mucosal (1/4 [25%]), or both regions (1/4 [25%]) and was centered in the supraglottis (4/4 [100%]) but also involved the glottis (4/4 [100%]) and subglottis (2/4 [50%]). Laryngeal tumor involved the aryepiglottic folds (4/4 [100%)]), ventricles and false cords (4/4 [100%]), epiglottis (3/4 [75%]), paraglottis (3/4 [75%]), true cords (4/4 [100%]), anterior commissure (4/4 [100%]), and laryngeal cartilage (1/4 [25%]). The tumor extended into the hypopharynx (4/4 [100%]), strap muscles (1/4 [25%]), prevertebral muscles (1/4 [25%]), tongue base (1/4 [25%]), and walls of the oropharynx (1/4 [25%]) and nasopharynx (1/4 [25%]). Bilateral cervical lymphadenopathy with extracapsular tumor spread was present in one patient. CONCLUSION: Laryngeal NHL is a tumor that usually has a large submucosal component centered in the surpaglottis. The tumor extends into the glottis, with less frequent spread to the subglottis, laryngeal cartilage, and strap muscles. Laryngeal NHL also involves the hypopharynx, with large tumors extending superiorly into the tongue base, oropharynx, and nasopharynx. A laryngeal tumor with a large supraglottic submucosal component should alert the ragiologist to the possibility of NHL. (+info)The laryngeal mucosa is the mucous membrane that lines the interior surface of the larynx, also known as the voice box. This mucous membrane is composed of epithelial cells and underlying connective tissue, and it plays a crucial role in protecting the underlying tissues of the larynx from damage, infection, and other environmental insults.
The laryngeal mucosa is continuous with the respiratory mucosa that lines the trachea and bronchi, and it contains numerous mucus-secreting glands and cilia that help to trap and remove inhaled particles and microorganisms. Additionally, the laryngeal mucosa is richly innervated with sensory nerve endings that detect changes in temperature, pressure, and other stimuli, allowing for the regulation of breathing, swallowing, and voice production.
Damage to the laryngeal mucosa can occur as a result of various factors, including irritants, infection, inflammation, and trauma, and may lead to symptoms such as pain, swelling, difficulty swallowing, and changes in voice quality.
The larynx, also known as the voice box, is a complex structure in the neck that plays a crucial role in protection of the lower respiratory tract and in phonation. It is composed of cartilaginous, muscular, and soft tissue structures. The primary functions of the larynx include:
1. Airway protection: During swallowing, the larynx moves upward and forward to close the opening of the trachea (the glottis) and prevent food or liquids from entering the lungs. This action is known as the swallowing reflex.
2. Phonation: The vocal cords within the larynx vibrate when air passes through them, producing sound that forms the basis of human speech and voice production.
3. Respiration: The larynx serves as a conduit for airflow between the upper and lower respiratory tracts during breathing.
The larynx is located at the level of the C3-C6 vertebrae in the neck, just above the trachea. It consists of several important structures:
1. Cartilages: The laryngeal cartilages include the thyroid, cricoid, and arytenoid cartilages, as well as the corniculate and cuneiform cartilages. These form a framework for the larynx and provide attachment points for various muscles.
2. Vocal cords: The vocal cords are thin bands of mucous membrane that stretch across the glottis (the opening between the arytenoid cartilages). They vibrate when air passes through them, producing sound.
3. Muscles: There are several intrinsic and extrinsic muscles associated with the larynx. The intrinsic muscles control the tension and position of the vocal cords, while the extrinsic muscles adjust the position and movement of the larynx within the neck.
4. Nerves: The larynx is innervated by both sensory and motor nerves. The recurrent laryngeal nerve provides motor innervation to all intrinsic laryngeal muscles, except for one muscle called the cricothyroid, which is innervated by the external branch of the superior laryngeal nerve. Sensory innervation is provided by the internal branch of the superior laryngeal nerve and the recurrent laryngeal nerve.
The larynx plays a crucial role in several essential functions, including breathing, speaking, and protecting the airway during swallowing. Dysfunction or damage to the larynx can result in various symptoms, such as hoarseness, difficulty swallowing, shortness of breath, or stridor (a high-pitched sound heard during inspiration).
The laryngeal nerves are a pair of nerves that originate from the vagus nerve (cranial nerve X) and provide motor and sensory innervation to the larynx. There are two branches of the laryngeal nerves: the superior laryngeal nerve and the recurrent laryngeal nerve.
The superior laryngeal nerve has two branches: the external branch, which provides motor innervation to the cricothyroid muscle and sensation to the mucous membrane of the laryngeal vestibule; and the internal branch, which provides sensory innervation to the mucous membrane of the laryngeal vestibule.
The recurrent laryngeal nerve provides motor innervation to all the intrinsic muscles of the larynx, except for the cricothyroid muscle, and sensation to the mucous membrane below the vocal folds. The right recurrent laryngeal nerve has a longer course than the left one, as it hooks around the subclavian artery before ascending to the larynx.
Damage to the laryngeal nerves can result in voice changes, difficulty swallowing, and respiratory distress.
Laryngitis is a medical condition characterized by inflammation of the larynx, or voice box. This inflammation can lead to hoarseness, throat pain, and difficulty speaking or swallowing. Laryngitis can be caused by viral infections, bacterial infections, vocal strain, or other factors such as exposure to irritants like smoke or chemicals. In some cases, laryngitis may be a symptom of a more serious underlying condition, so it is important to seek medical attention if symptoms persist for more than a few days or are accompanied by other concerning symptoms.
Laryngeal diseases refer to conditions that affect the structure and function of the larynx, also known as the voice box. The larynx is a complex structure composed of cartilages, muscles, membranes, and mucous glands that play essential roles in breathing, swallowing, and vocalization.
Laryngeal diseases can be categorized into several types based on their causes and manifestations. Some common laryngeal diseases include:
1. Laryngitis: Inflammation of the larynx that can cause hoarseness, throat pain, coughing, and difficulty swallowing. Acute laryngitis is often caused by viral infections or irritants, while chronic laryngitis may result from prolonged exposure to smoke, chemicals, or acid reflux.
2. Vocal cord lesions: Abnormal growths on the vocal cords, such as polyps, nodules, or cysts, that can affect voice quality and cause hoarseness, breathiness, or pain. These lesions are often caused by overuse, misuse, or trauma to the vocal cords.
3. Laryngeal cancer: Malignant tumors that develop in the larynx and can invade surrounding structures, such as the throat, neck, and chest. Laryngeal cancer is often associated with smoking, alcohol consumption, and human papillomavirus (HPV) infection.
4. Laryngeal stenosis: Narrowing of the airway due to scarring or thickening of the tissues in the larynx. This condition can cause difficulty breathing, wheezing, and coughing, especially during physical activity or sleep.
5. Reinke's edema: Swelling of the vocal cords caused by fluid accumulation in the mucous membrane that covers them. Reinke's edema is often associated with smoking and can cause hoarseness, low voice, and difficulty projecting the voice.
6. Laryngeal papillomatosis: A rare condition characterized by the growth of benign tumors (papillomas) in the larynx, usually caused by HPV infection. These tumors can recur and may require repeated surgeries to remove them.
7. Vocal cord paralysis: Inability of one or both vocal cords to move due to nerve damage or other medical conditions. This condition can cause hoarseness, breathiness, and difficulty speaking or swallowing.
These are some of the common laryngeal disorders that can affect a person's voice, breathing, and swallowing functions. Proper diagnosis and treatment by an otolaryngologist (ear, nose, and throat specialist) are essential to manage these conditions effectively and prevent complications.
The laryngeal muscles are a group of skeletal muscles located in the larynx, also known as the voice box. These muscles play a crucial role in breathing, swallowing, and producing sounds for speech. They include:
1. Cricothyroid muscle: This muscle helps to tense the vocal cords and adjust their pitch during phonation (voice production). It is the only laryngeal muscle that is not innervated by the recurrent laryngeal nerve. Instead, it is supplied by the external branch of the superior laryngeal nerve.
2. Posterior cricoarytenoid muscle: This muscle is primarily responsible for abducting (opening) the vocal cords during breathing and speaking. It is the only muscle that can abduct the vocal cords.
3. Lateral cricoarytenoid muscle: This muscle adducts (closes) the vocal cords during phonation, swallowing, and coughing.
4. Transverse arytenoid muscle: This muscle also contributes to adduction of the vocal cords, working together with the lateral cricoarytenoid muscle. It also helps to relax and lengthen the vocal cords during quiet breathing.
5. Oblique arytenoid muscle: This muscle is involved in adducting, rotating, and shortening the vocal cords. It works together with the transverse arytenoid muscle to provide fine adjustments for voice production.
6. Thyroarytenoid muscle (Vocalis): This muscle forms the main body of the vocal cord and is responsible for its vibration during phonation. The vocalis portion of the muscle helps control pitch and tension in the vocal cords.
These muscles work together to enable various functions of the larynx, such as breathing, swallowing, and speaking.
A reflex is an automatic, involuntary and rapid response to a stimulus that occurs without conscious intention. In the context of physiology and neurology, it's a basic mechanism that involves the transmission of nerve impulses between neurons, resulting in a muscle contraction or glandular secretion.
Reflexes are important for maintaining homeostasis, protecting the body from harm, and coordinating movements. They can be tested clinically to assess the integrity of the nervous system, such as the knee-j jerk reflex, which tests the function of the L3-L4 spinal nerve roots and the sensitivity of the stretch reflex arc.
The intestinal mucosa is the innermost layer of the intestines, which comes into direct contact with digested food and microbes. It is a specialized epithelial tissue that plays crucial roles in nutrient absorption, barrier function, and immune defense. The intestinal mucosa is composed of several cell types, including absorptive enterocytes, mucus-secreting goblet cells, hormone-producing enteroendocrine cells, and immune cells such as lymphocytes and macrophages.
The surface of the intestinal mucosa is covered by a single layer of epithelial cells, which are joined together by tight junctions to form a protective barrier against harmful substances and microorganisms. This barrier also allows for the selective absorption of nutrients into the bloodstream. The intestinal mucosa also contains numerous lymphoid follicles, known as Peyer's patches, which are involved in immune surveillance and defense against pathogens.
In addition to its role in absorption and immunity, the intestinal mucosa is also capable of producing hormones that regulate digestion and metabolism. Dysfunction of the intestinal mucosa can lead to various gastrointestinal disorders, such as inflammatory bowel disease, celiac disease, and food allergies.
Gastric mucosa refers to the innermost lining of the stomach, which is in contact with the gastric lumen. It is a specialized mucous membrane that consists of epithelial cells, lamina propria, and a thin layer of smooth muscle. The surface epithelium is primarily made up of mucus-secreting cells (goblet cells) and parietal cells, which secrete hydrochloric acid and intrinsic factor, and chief cells, which produce pepsinogen.
The gastric mucosa has several important functions, including protection against self-digestion by the stomach's own digestive enzymes and hydrochloric acid. The mucus layer secreted by the epithelial cells forms a physical barrier that prevents the acidic contents of the stomach from damaging the underlying tissues. Additionally, the bicarbonate ions secreted by the surface epithelial cells help neutralize the acidity in the immediate vicinity of the mucosa.
The gastric mucosa is also responsible for the initial digestion of food through the action of hydrochloric acid and pepsin, an enzyme that breaks down proteins into smaller peptides. The intrinsic factor secreted by parietal cells plays a crucial role in the absorption of vitamin B12 in the small intestine.
The gastric mucosa is constantly exposed to potential damage from various factors, including acid, pepsin, and other digestive enzymes, as well as mechanical stress due to muscle contractions during digestion. To maintain its integrity, the gastric mucosa has a remarkable capacity for self-repair and regeneration. However, chronic exposure to noxious stimuli or certain medical conditions can lead to inflammation, erosions, ulcers, or even cancer of the gastric mucosa.
The mouth mucosa refers to the mucous membrane that lines the inside of the mouth, also known as the oral mucosa. It covers the tongue, gums, inner cheeks, palate, and floor of the mouth. This moist tissue is made up of epithelial cells, connective tissue, blood vessels, and nerve endings. Its functions include protecting the underlying tissues from physical trauma, chemical irritation, and microbial infections; aiding in food digestion by producing enzymes; and providing sensory information about taste, temperature, and texture.