Gender-specific distribution of glycosaminoglycans during cartilage mineralization of human thyroid cartilage

Postnatal changes in thyroid cartilage shape and cartilage matrix composition are not synchronized in Mus musculus

The study was conducted to quantify laryngeal cartilage matrix composition and to investigate its relationship with cartilage shape in a mouse model. A sample of 30 mice (CD-1 mouse, Mus musculus) from five age groups (postnatal Days 2, 21, 90, 365, and 720) were used. Three-dimensional mouse laryngeal thyroid cartilage reconstructions were generated from contrast-enhanced micro-computed tomography (CT) image stacks. Cartilage matrix composition was estimated as Hounsfield units (HU). HU were determined by overlaying 3D reconstructions as masks on micro-CT image stacks and then measuring the attenuation. Cartilage shape was quantified with landmarks placed on the surface of the thyroid cartilage. Shape differences between the five age groups were analyzed using geometric morphometrics and multiparametric analysis of landmarks. The relationship between HU and shape was investigated with correlational analyses. Among five age groups, HU became higher in older animals. The shape of the thyroid cartilage changes with age throughout the entire life of a mouse. The changes in shape were not synchronized with changes in cartilage matrix composition. The thyroid cartilage of young and old M. musculus larynx showed a homogenous mineralization pattern. High-resolution contrast-enhanced micro-CT imaging makes the mouse larynx accessible for analysis of genetic and environmental factors affecting shape and matrix composition.

Two Cases of Atraumatic Laryngeal Fractures

INTRODUCTION AND AIM

Atraumatic laryngeal fractures are extremely rare and are most commonly provoked by sneezing or coughing. Only seven cases have been described in medical literature, and only one case described a fracture after swallowing. We present two cases of atraumatic laryngeal fracture after swallowing.

CASE REPORT

A 37-year-old male presented to the outpatient ENT clinic with severe dysphonia and odynophagia. He reported feeling a crack in the throat after swallowing with a flexed head. The patient's physical examination showed diffuse swelling and tenderness over the thyroid cartilage without subcutaneous emphysema. Flexible nasolaryngoscopy showed a large right true vocal fold hematoma with normal vocal fold movement. Computed tomography (CT) showed a fracture of the thyroid. Treatment consisted of corticosteroids and pantoprazole. Two years later he presented again at the emergency department with extreme odynophagia after suffering a knee punch on the larynx. CT showed a new fracture line, slightly off midline to the left in the thyroid cartilage. A 42-year-old male presented at the emergency department with odynophagia, dysphonia, and fever after feeling a crack in the throat during forceful swallowing in an extended neck position. Physical examination demonstrated a painful thyroid cartilage with subcutaneous emphysema. Flexible nasolaryngoscopy was normal but CT scan showed a slightly displaced fracture line of the median thyroid cartilage. Complaints gradually disappeared with conservative treatment with corticosteroids and antibiotics.

CONCLUSION

Congenital anomalies by abnormal mineralization and ossification could lead to focal weakness of the thyroid cartilage and thus predispose to non-traumatic fractures. The double triad of odynophagia, dysphagia, and dysphonia after sneezing, coughing or swallowing should raise the physician's attention to the possibility of thyroid cartilage fracture, especially after feeling or hearing a crack. Further investigation is obligatory with high-resolution CT of the neck and examination by an ENT specialist.

Effects of dietary camelina, flaxseed, and canola oil supplementation on inflammatory and oxidative markers, transepidermal water loss, and coat quality in healthy adult dogs

Introduction

Camelina oil contains a greater concentration of omega-3 (n-3) a-linolenic acid (C18:3n-3; ALA) than omega-6 (n-6) linoleic acid (C18:2n-6; LA), in comparison to alternative fat sources commonly used to formulate canine diets. Omega-3 FAs are frequently used to support canine skin and coat health claims and reduce inflammation and oxidative stress; however, there is a lack of research investigating camelina oil supplementation and its effects on these applications in dogs. The objective of this study was to evaluate the effects of camelina oil supplementation on coat quality, skin barrier function, and circulating inflammatory and oxidative marker concentrations.

Methods

Thirty healthy [17 females; 13 males; 7.2 ± 3.1 years old; 27.4 ± 14.0 kg body weight (BW)] privately-owned dogs of various breeds were used. After a 4-week wash-in period consuming sunflower oil (n6:n3 = 1:0) and a commercial kibble, dogs were blocked by age, breed, and size, and randomly assigned to one of three treatment oils: camelina (n6:n3 = 1:1.18), canola (n6:n3 = 1:0.59), flaxseed (n6:n3 = 1:4.19) (inclusion level: 8.2 g oil/100 g of total food intake) in a randomized complete block design. Transepidermal water loss (TEWL) was measured using a VapoMeter on the pinna, paw pad, and inner leg. Fasted blood samples were collected to measure serum inflammatory and oxidative marker concentrations using enzyme-linked immunosorbent assay (ELISA) kits and spectrophotometric assays. A 5-point-Likert scale was used to assess coat characteristics. All data were collected on weeks 0, 2, 4, 10, and 16 and analyzed using PROC GLIMMIX in SAS.

Results

No significant changes occurred in TEWL, or inflammatory and oxidative marker concentrations among treatments, across weeks, or for treatment by week interactions. Softness, shine, softness uniformity, color intensity, and follicle density of the coat increased from baseline in all treatment groups (P < 0.05).

Discussion

Outcomes did not differ (P > 0.05) among treatment groups over 16-weeks, indicating that camelina oil is comparable to existing plant-based canine oil supplements, flaxseed, and canola, at supporting skin and coat health and inflammation in dogs. Future research employing an immune or exercise challenge is warranted, as the dogs in this study were not subjected to either.

Clinicopathologic characteristics of laryngeal chondrosarcoma: An analysis of the National Cancer Database

OBJECTIVES

Laryngeal Chondrosarcoma (LC) is a rare malignancy with limited studies documenting its clinicopathologic characteristics and treatment options. This study reports demographic and clinical determinants of outcomes for this rare tumor.

METHODS

The National Cancer Database (NCDB) was queried for cases of LC reported from 2004-2016. 274 cases that met inclusion criteria were analyzed for demographic and clinicopathologic characteristics. Kaplan-Meier (KM) and Cox proportional hazard analyses were conducted to identify variables that impacted the overall survival of these patients.

RESULTS

LC was found to be more common in males (74.8%). The mean age of patients was 61.8 years and 92.3% of the patients were white. 91.3% of patients were treated with only surgical resection, most commonly: partial laryngectomy (31.6%), total laryngectomy (25.7%), and local resection (22.4%). 98.8% of patients had no evidence of nodal disease and 99.6% of patients did not have distant metastasis at presentation. KM analysis revealed a 5-year overall survival (5YOS) of 89.0%. Age, insurance status, facility type, and surgery type were significant predictors of 5YOS (p<0.05). On Cox Proportional Hazard analysis, private insurance significantly improved survival (HR 0.21; p = 0.048) while increasing age was a poor prognostic indicator (HR 1.10; p = 0.004).

CONCLUSION

The majority of LC patients present with no nodal involvement or distant metastasis at diagnosis, and overall this tumor has a favorable prognosis. Increasing age was found to be a poor prognostic factor while private insurance status was associated with improved survival.

Non-Traumatic Laryngeal Fractures: A Systematic Review

Non-traumatic laryngeal fractures are an extremely uncommon presentation, and the diagnosis can be missed. Recognizing these fractures is important to appropriately direct management because most have a good prognosis and result in complete recovery. This article aimed to review the characteristics of all documented cases of non-traumatic fractures of the larynx. We sought to address questions related to the etiology, clinical presentation, and diagnostic assessment of this condition and provide recommendations about the management of these fractures. Electronic databases, mainly PubMed and Google Scholar, were searched for relevant literature with no language or time restrictions. Since 1950, 15 cases of non-traumatic laryngeal fractures have been documented in the medical literature. Out of these, thyroid cartilage fractures have been described in 14 patients, while only one instance demonstrated a fracture in the cricoid cartilage. Patients were managed conservatively using voice rest and observation with complete recovery in all cases. All patients who present with odynophagia, hoarseness, and tenderness over the thyroid cartilage after an episode of severe coughing or sneezing, should be evaluated for a thyroid cartilage fracture using laryngoscopy and computed tomography scan. Management of the airway should be the primary priority in any laryngeal injury, and further management performed after the airway is stable.

An investigation on annular cartilage samples for post-mortem interval estimation using Fourier transform infrared spectroscopy

Many attempts have been made to estimate the post-mortem interval (PMI) using bioanalytical methods based on multiple biological samples. Cartilage tissues could be used as an alternative for this purpose because their rate of degradation is slower than that of other soft tissue or biofluid samples. In this study, we applied Fourier transform infrared (FTIR) spectroscopy to acquire bioinformation from human annular cartilages within 30 days post-mortem. Principal component analysis (PCA) showed that sex and causes of death have almost no impact on the overall spectral variations caused by post-mortem changes. With pre-processing approaches, several predicted models were established using a conventional machine learning method, known as the partial least square (PLS) regression. The best model achieved a satisfactory prediction with a low error of 1.49 days using the second derivative transform of 3-point smoothing and extended multiplicative scatter correction (EMSC), and the spectral regions from proteins and carbohydrates contributed greatly to the PMI prediction. This study demonstrates the feasibility of cartilage-based FTIR analysis for PMI estimation. Further work will introduce advanced algorithms for more accurate and precise PMI prediction.

Mechanical, Cellular, and Proteomic Properties of Laryngotracheal Cartilage

The larynx sometimes requires repair and reconstruction due to cancer resection, trauma, stenosis, or developmental disruptions. Bioengineering has provided some scaffolding materials and initial attempts at tissue engineering, especially of the trachea, have been made. The critical issues of providing protection, maintaining a patent airway, and controlling swallowing and phonation, require that the regenerated laryngotracheal cartilages must have mechanical and material properties that closely mimic native tissue. These properties are determined by the cellular and proteomic characteristics of these tissues. However, little is known of these properties for these specific cartilages. This review considers what is known and what issues need to be addressed.

Sonographic evaluation of the endochondral ossification process of the thyroid cartilage in children

PURPOSE

To determine the sonographic appearances of the endochondral ossification process of the thyroid cartilage in children.

METHODS

Thyroid cartilage sonography (US) of 420 children was performed with a high-resolution linear-array transducer. Right and left laminae of the thyroid cartilage, including the inferior horns, were examined. Ossification foci were evaluated for their presence, location, shape, size, echo pattern, and number.

RESULTS

Four hundred nineteen children, 239 girls and 180 boys, were enrolled in the study with a mean age of 109.8 ± 60.7 months. Ossification foci were found in 167 children (39.9%). First ossification focus detection age was 72 months in girls and 79 months in boys. On both laminae, the most frequent appearance of the ossification focus was hypoechoic (right: 94.8%, left: 93.5%). Prevalence and number of ossification foci increased with age in each sex. The shape of the ossification foci in both laminae was generally nonexpansile (right: 92.9%, left: 93.5%).

CONCLUSION

Endochondral ossification process of the thyroid cartilage begins in the first decade with extracellular matrix changes, which can be detected as hypoechoic foci by US. These foci can be expansile, and radiologists should be aware of this entity to avoid misdiagnosing them as abnormal masses.

Structure and composition of arytenoid cartilage of the bullfrog (Lithobates catesbeianus) during maturation and aging

The aging process induces progressive and irreversible changes in the structural and functional organization of animals. The objective of this study was to evaluate the effects of aging on the structure and composition of the extracellular matrix of the arytenoid cartilage found in the larynx of male bullfrogs (Lithobates catesbeianus) kept in captivity for commercial purposes. Animals at 7, 180 and 1080 days post-metamorphosis (n=10/age) were euthanized and the cartilage was removed and processed for structural and biochemical analysis. For the structural analyses, cartilage sections were stained with picrosirius, toluidine blue, Weigert's resorcin-fuchsin and Von Kossa stain. The sections were also submitted to immunohistochemistry for detection of collagen types I and II. Other samples were processed for the ultrastructural and cytochemical analysis of proteoglycans. Histological sections were used to chondrocyte count. The number of positive stainings for proteoglycans was quantified by ultrastructural analysis. For quantification and analysis of glycosaminoglycans were used the dimethyl methylene blue and agarose gel electrophoresis methods. The chloramine T method was used for hydroxyproline quantification. At 7 days, basophilia was observed in the pericellular and territorial matrix, which decreased in the latter over the period studied. Collagen fibers were arranged perpendicular to the major axis of the cartilaginous plate and were thicker in older animals. Few calcification areas were observed at the periphery of the cartilage specimens in 1080-day-old animals. Type II collagen was present throughout the stroma at the different ages. Elastic fibers were found in the stroma and perichondrium and increased with age in the two regions. Proteoglycan staining significantly increased from 7 to 180 days and reduced at 1080 days. The amount of total glycosaminoglycans was higher in 180-day-old animals compared to the other ages, with marked presence of chondroitin- and dermatan-sulfate especially in this age. The content of hydroxyproline, which infers the total collagen concentration, was higher in 1080-day-old animals compared to the other ages. The results demonstrated the elastic nature of the arytenoid cartilage of L. catesbeianus and the occurrence of age-related changes in the structural organization and composition of the extracellular matrix. These changes may contribute to alter the function of the larynx in the animal during aging.

Histopathological effects of estrogen deficiency on larynx mucosa in ovariectomised rats

Laryngeal manifestations due to estrogen deficiency have been studied in the literature. But to date, the possible histopathological changes of laryngeal mucosa due to estrogen deficiency have not been studied. Therefore, our objective was to determine the histopathological changes of laryngeal mucosa in ovariectomised rats in order to clarify effects of estrogen deficiency on laryngeal tissue. The study is a randomized trial and was conducted at the animal care facility of Haydarpasa Numune Education and Research Hospital. Twenty-one Wistar rats were used throughout the experiment. There were six rats in the sham-operated control group. And others were divided into two groups (4, 8 weeks) according to follow-up time after ovariectomy. We observed significant changes 4 weeks after ovariectomy when we assessed subepithelial edema, inflammation, cilia and goblet cell loss (p < 0.01). It was shown that estrogen deficiency after ovariectomy in rats caused changes in laryngeal tissue when it was studied histopathologically.

The fate of chondrocytes during ageing of human thyroid cartilage

Human laryngeal cartilages, especially thyroid cartilage, exhibit gender-specific ageing. In contrast to male thyroid cartilages, the ventral half of the female thyroid cartilage plate remains unmineralized until advanced age. In cartilage specimens from laryngectomies and autopsies, apoptosis was studied immunohistochemically and the oxidative mitochondrial enzyme nicotinamide adenine dinucleotide hydride tetrazolium reductase (NADH-TR) was localized histochemically. In addition, very fresh specimens from laryngectomies were fixed under addition of ruthenium hexamine trichloride or tannin to fixation solution to study cell organelles of chondrocytes by electron microscopic methods. In general, apoptotic chondrocytes decreased in thyroid cartilages of both genders, especially after the second decade. In the age group 41-60 years, thyroid cartilage from male specimens revealed a significantly higher percentage of apoptotic cells than did thyroid cartilage from women (P = 0.004), whereas in the age groups 0-20 years and 61-79 years no statistically significant gender difference was determined. In general, thyroid cartilage from women contained more living chondrocytes into advanced age than men. Chondrocytes adjacent to mineralized cartilage were partly positive for apoptosis and NADH-TR and partly negative. Apoptotic chondrocytes often were localized in areas of asbestoid fibres where vascularization and mineralization took place first. Electron microscopy revealed remnants of chondrocytes in asbestoid fibres. Taken together, it can be assumed that some chondrocytes in thyroid cartilage die by apoptosis and that these chondrocytes are characterized by absent reactivity for the mitochondrial enzyme NADH-TR. A possible influence of sexual hormones on apoptotic death of thyroid cartilage cells requires further elucidation.

Ossification of laryngeal structures as indicators of age

As the role of forensic anthropologists expands to the medical examiner setting, their expertise is being applied beyond the traditional dry skeletal material. In such scenarios radiographic techniques can be applied when maceration is not appropriate. This study explores the use of radiographic analysis of laryngeal structures for age-at-death determination. Isolated human laryngeal structures (n = 104) from individuals between the ages of 15 and 89 were removed at autopsy and radiographically examined. The cricoid and individual regions of the thyroid cartilage were scored according to degree of ossification, and the relationship between age and degree of ossification statistically examined. A previously published study on age-determination from thyroid ossification by Cerný was assessed for accuracy. The results of the study indicate that although a consistent sequence in the ossification of laryngeal structures exists, variations in timing does not permit narrow age range estimates. Consequently the method presented by Cerný is inaccurate and should not be used in the forensic setting.

Glycosaminoglycan, collagen, and glycosidase changes in human osteoblasts treated with interleukin 1, and osteodystrophy

Normal bone homeostasis involves a balance between osteoblast and osteoclast action, regulated by hormones and cytokine stimuli. Hemodialysis patients appear to have increased production of interleukin-1 (IL-1), interleukin-6 (IL-6) and glycosaminoglycans (GAG) in serum. IL-1 plays a role in the synthesis, degradation and degree of sulphatation of ECM components such as glycosaminoglycans. Also, continuous changes in the ECM involve enzymes such as beta-N-acetyl-d-glucosaminidase (beta-NAG) and beta-d-glucuronidase (beta-GLU) which act on different GAG classes and collagen fibers. We examined the effects of IL-1alpha on ECM synthesis and the related enzymes in human uremic osteoblast cultures. We also measured the levels of IL-1beta, and IL-6 and alkaline phosphatase activity. In biopsies of uremic bone there was less ECM deposition than resorption associated with changes in osteoblast morphology. In vitro osteoblast proliferation was higher (P< or =0.01), and extracellular GAG lower (P< or =0.01) than in controls. The enzyme beta-NAG was high (P< or =0.05) but there were no noteworthy changes in beta-GLU. ELISA of the medium indicated spontaneous production of IL-1beta and IL-6, which significantly increased after IL-1alpha treatment compared to controls. IL-1alpha reduced alkaline phosphatase activity (P< or =0.01) in uremic osteoblast cultures. IL-1 acts on osteoblasts with decreases in GAG synthesis and alkaline phosphatase activity, while beta-NAG increases. This lead to a reduction in the organic component in ECM and its mineralization, and to changes in the regulation of cytokine activity by GAG. The enzymatic breakdown might be facilitated by metabolic acidosis and failed osteoblast differentiation; these factors could be correlated with different degrees of osteodystrophy.

Update Larynx: funktionelle Anatomie unter klinischen Gesichtspunkten

ENT specialist and phoniatricians are not the only professionals for whom diseases of the larynx occupy centre stage; this applies to those in all fields involving conservative or surgical treatment of the larynx, such as speech therapists, paediatricians, anaesthetists, oncologists, pulmonologists, radiologists and general practitioners. On the basis of current knowledge and taking account of results yielded by their own research in recent years and of clinical aspects, in this paper the authors give a short overview of basic knowledge on the anatomy and physiology of the larynx. Part 1 deals with its development and division, the laryngeal skeleton and joints, the insertion structures of the vocal folds and the laryngeal musculature and describes new insights into the mineralization and ossification of the laryngeal skeleton and their implications for phonation, arytenoid subluxation, degenerative joint changes and the biomechanics of vocal cord insertion.