elastin and Cadaver

Surgical implantation of decellularized cadaveric arteries is routinely used to treat right-sided congenital cardiac lesions. These acellular conduits lack the capacity for somatic growth and are prone to stenosis and calcification, necessitating multiple operations throughout childhood. Islet-1+ cardiovascular progenitor cells (CPCs) have demonstrated the capacity for differentiation into all cell types of the heart and outflow tracts. We hypothesize that CPC seeding of decellularized pulmonary arteries and bioreactor culture under physiologic flow conditions will drive vascular differentiation of CPCs and result in a conduit more suitable for implantation and long-term growth. We began by decellularizing ovine pulmonary arteries and characterizing the composition of the extracellular matrix (ECM). Hemodynamic testing of decellularized vessels in a custom bioreactor was used to define the scaffold mechanical properties over a range of pressures and flow rates. Next, our expanded ovine CPCs were suspended in growth media and injected intramurally into decellularized pulmonary arteries that were subsequently cultured in either static or pulsatile cultures. A combination of immunohistochemistry, real-time polymerase chain reaction (PCR), and tissue bath contraction studies were used to evaluate the bioengineered arteries before transplantation. Pulmonary artery patches from the most favorable culture conditions were then implanted into juvenile sheep to provide proof of concept. Hematoxylin and eosin staining indicated complete removal of cell nuclei (

Topics: Animals; Biomimetics; Blood Vessel Prosthesis; Cadaver; Cells, Cultured; Elastin; Muscle Contraction; Pilot Projects; Pulsatile Flow; Sheep; Tissue Engineering; Tissue Scaffolds

To define the localization and configuration of the elastic fibers of the cricoarytenoid ligament (CAL) and their relationship with the cricoarytenoid joint (CAJ) capsule.. Twenty-four CAJs from twelve cadavers were analyzed using Verhoeff-Van Gieson staining, and immunohistochemistry methods. This is a prospective study.. The CAL was classified into two parts: an extra-capsular anterior-CAL and an intra-capsular posterior-CAL. The both parts contained rich elastic fibers. The elastic fibers of the anterior-CAL were orientated in both anterior-posterior and superior-inferior directions and under a relaxation status, whereas the elastic fibers of the posterior-CAL were arranged in a lateral-medial direction and under a taut status.. This study defined the fine configuration of the CAL, particularly its elastic fibers, which may help us to better understand the biomechanics of the CAJ motions, and differential diagnosis of CAJ disorders. The results of the study re-confirm that the P-CAL is the key posterior-lateral passive force to limit the mobility of the muscular process of the arytenoid cartilage and stabilize the CAJ, whereas the A-CAL may protect the CAJ from an over superior-lateral-posterior motion.. H/A.

Topics: Aged; Arytenoid Cartilage; Cadaver; Elastic Tissue; Elastin; Humans; Ligaments; Prospective Studies

The aim of the study was to assess the relationship between the expression of elastin, collagen type I, II,III and the degenera- tion of the facet joint capsule and the ligamentum flavum.. 10 patients (4 male, 6 female) (mean age 61 ± 14,9) undergoing surgery for degenerative lumbar spine syndrome and 5 cadav- ers (3 male, 2 female) (age of death 87 ± 8,6 years) were included in this study. One set of tissue samples was taken from each patient in the patient group intraoperatively and two sets of samples were taken from each cadaver in the cadaver group posthumosly from the ligamentum flavum (medial and lateral) and from the facet joint capsules (superior and inferior articular process) at the L4/5 segment. Western blot analysis was performed for collagen types I, II, III and for elastin. Disc degeneration was scored according to the Pfirmann Classification, facet joint arthrosis was scored according to the Fujiwara Classification and their relationship with protein expression was investigated.. There was a strong expression of Collagen type I in the patient group (PG) compared to the body donor group (BDG) in the facet joint capsule (FJC) and in the lateral samples of the ligamentum flavum. Samples of the FJC showed lower expression of elastin in the PG compared with the BDG, but without statistical significance. An increased expression of collagen type I compared to elastin in the PG could be shown. In contrast, elastin predominated in the samples of the BDG group compared to collagen type I (collagen type I/ elastin PG: PAsup 2,78; PAinf 2,61; LFmed 2,23; 225 LFlat 1,83; BDG: PAsup 0,15; PAinf 0,2; LFmed 0,2; LFlat 0,27). Rank correlation coefficient according to Spearman showed low to moderate correlations for collagen type I, III and elastin for the degree of disc degeneration accord- ing to Pfirrmann and the degree of facet joint osteoarthritis according to Fujiwara, all of them without statistical significance.. This study has shown us that in the context of degenerative changes of the lumbar spine, there is an increased expression of collagen type I and a dominance over elastin.. Level III, Diagnostic Study.

Topics: Aged, 80 and over; Cadaver; Collagen; Collagen Type I; Elastin; Female; Humans; Intervertebral Disc Degeneration; Joint Capsule; Ligamentum Flavum; Lumbar Vertebrae; Male; Middle Aged; Zygapophyseal Joint

This study aims to address the potential of ex vivo diffusion tensor imaging to provide insight into the microstructural composition and morphological arrangement of aged human atherosclerotic carotid arteries.. In this study, whole human carotid arteries were investigated both anatomically and by comparing healthy and diseased regions. Nonrigid image registration was used with unsupervised segmentation to investigate the influence of elastin, collagen, cell density, glycosaminoglycans, and calcium on diffusion tensor imaging derived metrics (fractional anisotropy and mean diffusivity). Early stage atherosclerotic features were also investigated in terms of microstructural components and diffusion tensor imaging metrics.. All vessels displayed a dramatic decrease in fractional anisotropy compared with healthy animal arterial tissue, while the mean diffusivity was sensitive to regions of advanced disease. Elastin content strongly correlated with both fractional anisotropy (r>0.7,. These different investigations point to the potential of diffusion tensor imaging to identify characteristics of arterial disease progression, at early and late-stage lesion development.

Topics: Aged; Animals; Biomarkers; Cadaver; Calcium; Carotid Arteries; Diffusion Tensor Imaging; Elastin; Glycosaminoglycans; Humans

The shape and function of the longitudinal muscular column (LMC) of the prostate have not been established in detail. The present study was undertaken to elucidate the roles of the LMC of the posterior wall of the prostatic urethra (PSU) in the emission phase of ejaculation by investigating the form and muscular arrangement of the LMC.. Prostates and urinary bladders were obtained from 14 Korean adult cadavers. Nine specimens were histologically analyzed using hematoxylin and eosin, Masson's trichrome, and Verhoeff-van Gieson staining. Two specimens were scanned using microcomputed tomography (micro-CT), and all scanned images were reconstructed into a three-dimensional model.. At the proximal level of the prostate, the ejaculatory ducts (EDs) and prostatic utricle (PU) together were surrounded by circular smooth-muscle fibers. However, at the seminal colliculus (SC) where the EDs and PU opened, they were mainly surrounded by an abundance of longitudinal fibers. The longitudinal fibers posterior to the EDs and PU formed a distinctive LMC in the posterior urethral wall. In histologic sections and micro-CT images, the LMC extended distally from the level of the SC to the level of the membranous urethra (MBU). We simulated a potential mechanism of LMC using a mathematical model of its movements.. Comprehensive analyses based on in-depth assessment of histologic characteristics and micro-CT images demonstrated extension of the LMC from the level of the SC to the level of the MBU, enabling a better understanding of ejaculation physiology involving the LMC. These results suggest that the LMC in the posterior wall of the PSU is a critical component of ejaculation by facilitating the ejection of seminal vesicle fluid into the PSU via well-coordinated contractions.

Topics: Aged; Aged, 80 and over; Cadaver; Ejaculation; Elastin; Humans; Male; Middle Aged; Models, Anatomic; Models, Biological; Muscle, Smooth; Prostate; Urethra; X-Ray Microtomography

Bridging veins (BVs) drain the blood from the cerebral cortex into dural sinuses. BVs have one end attached to the brain and the other to the superior sagittal sinus (SSS), which is attached to the skull. Relative movement between these two structures can cause BV to rupture producing acute subdural haematoma, a head injury with a mortality rate between 30 and 90%. A clear understanding of the BVs microstructure is required to increase the biofidelity of BV models when simulating head impacts. Twelve fresh BV samples draining in the superior sagittal sinus (SSS) from a single human cadaver were cut open along their length and placed on an inverted multiphoton microscope. To ensure that the BVs were aligned with the axial direction an in-house built, uniaxial tension set-up was used. Two scans were performed per sample. Before the first scan, a minor displacement was applied to align the tissue; then, a second scan was taken applying 50% strain. Each BV was scanned for a length of 5 mm starting from the drainage site into the SSS. Imaging was performed on a Zeiss LSM780 microscope with an 25[Formula: see text] water immersion objective (NA 0.8), coupled to a tunable MaiTai DS (Spectraphysics) pulsed laser with the wavelength set at 850 nm. Second harmonic and fluorescence signals were captured in forward and backward direction on binary GaAsP (BiG) detectors and stored as four colour Z-stacks. Prior to the calculation of the local orientations, acquired Z-stacks were denoised and enhanced to highlight fibrillar structures from the background. Then, for each Z-plane of the stack, the ImageJ plugin OrientationJ was used to extract the local 2D orientations of the fibres based on structure tensors. Two kinds of collagen architectures were seen. The most common (8[Formula: see text]12 samples) was single layered and had a uniform distribution of collagen. The less common (4[Formula: see text]12 samples) had 2 layers and 7 to 34 times thicker collagen bundles on the outer layer. Fibre angle analysis showed that collagen was oriented mainly along the axial direction of the vessel. The von Mises fittings showed that in order to describe the fibre distribution 3 components were needed with mean angles [Formula: see text] at [Formula: see text] 0.35, 0.21, [Formula: see text] 0.02 rad or [Formula: see text] 20.2[Formula: see text], 12.1[Formula: see text], [Formula: see text] 1.2[Formula: see text] relative to the vessel's axial direction which was also the horizon

Topics: Adventitia; Aged; Biomechanical Phenomena; Cadaver; Cerebrovascular Circulation; Collagen; Elastin; Female; Hematoma, Subdural, Acute; Humans; Imaging, Three-Dimensional; Microscopy; Skull; Stress, Mechanical; Tunica Intima; Tunica Media; Veins

The perineal body connects muscles from the pelvic floor and is critical for support of the lower part of the vagina and proper function of the anal canal. We determined mechanical parameters and volume fractions of main components of the human female postmenopausal perineal body.. The specimens were taken from 15 fresh female cadavers (age 74 ± 10, mean ± standard deviation). Seventy-five specimens from five regions of the perineal body were processed histologically to assess volume fractions of tissue components using stereological point testing grid. Fifteen specimens taken from the midline region were loaded uniaxially with 6 mm/min velocity until tissue rupture to determine Young's modulus of elasticity, ultimate stresses, and strains.. The perineal body was composed of collagen (29%), adipose cells (27%), elastin (7%), smooth muscle (11%), and skeletal muscle (3%). The residual tissue (19%) constituted mostly peripheral nerves, lumina of blood vessels, fibroblasts, and fibrocytes. Young's modulus of elasticity at midline region was 18 kPa (median) at small and 232 kPa at large deformations, respectively. The ultimate stress was 172 kPa and the ultimate strain was 1.4.. We determined the structural and mechanical parameters of the perineal body. The resultant data could be used as input for models simulating pelvic floor prolapse or dysfunction.

Topics: Adipose Tissue; Aged; Aged, 80 and over; Anal Canal; Biomechanical Phenomena; Cadaver; Collagen; Elasticity; Elastin; Female; Humans; Middle Aged; Muscle, Skeletal; Muscle, Smooth; Pelvic Floor; Pelvic Organ Prolapse; Perineum; Postmenopause; Vagina

High-performance athletes can develop symptomatic arterial flow restriction during exercise caused by endofibrosis. The pathogenesis is poorly understood; however, coagulation enzymes, such as tissue factor (TF) and coagulation factor Xa, might contribute to the fibrotic process, which is mainly regulated through activation of protease-activated receptors (PARs). Therefore, the aim of this explorative study was to evaluate the presence of coagulation factors and PARs in endofibrotic tissue, which might be indicative of their potential role in the natural development of endofibrosis.. External iliac arterial specimens with endofibrosis (n = 19) were collected during surgical interventions. As control, arterial segments of the external iliac artery (n = 20) were collected post mortem from individuals with no medical history of cardiovascular disease who donated their body to medical science. Arteries were paraffinized and cut in tissue sections for immunohistochemical analysis. Positive staining within lesions was determined with ImageJ software (National Institutes of Health, Bethesda, Md).. Endofibrotic segments contained a neointima, causing intraluminal stenosis, which was highly positive for collagen (+150%; P < .01) and elastin (+148%; P < .01) in comparison with controls. Intriguingly, endofibrosis was not limited to the intima because collagen (+213%) and elastin (+215%) were also significantly elevated in the media layer of endofibrotic segments. These findings were accompanied by significantly increased α-smooth muscle actin-positive cells, morphologically compatible with the presence of myofibroblasts. In addition, PAR1 and PAR4 and the membrane receptor TF were increased as well as coagulation factor X.. We showed that myofibroblasts and the accompanying collagen and elastin synthesis might be key factors in the development of endofibrosis. The special association with increased presence of PARs, factor X, and TF suggests that protease-mediated cell signaling could be a contributing component in the mechanisms leading to endofibrosis.

Topics: Adult; Aged; Aged, 80 and over; Athletes; Athletic Performance; Cadaver; Case-Control Studies; Collagen; Constriction, Pathologic; Elastin; Factor X; Female; Fibrosis; Humans; Iliac Artery; Male; Middle Aged; Myofibroblasts; Peripheral Arterial Disease; Receptor, PAR-1; Receptors, Thrombin; Thromboplastin; Up-Regulation; Vascular Remodeling; Young Adult

Elastin is an abundant extracellular matrix protein in elastic tissues, including the lungs, skin and arteries, and comprises 30-57% of the aorta by dry mass. The monomeric precursor, tropoelastin (TE), undergoes complex processing during elastogenesis to form mature elastic fibres. Peroxynitrous acid (ONOOH), a potent oxidising and nitrating agent, is formed in vivo from superoxide and nitric oxide radicals. Considerable evidence supports ONOOH formation in the inflamed artery wall, and a role for this species in the development of human atherosclerotic lesions, with ONOOH-damaged extracellular matrix implicated in lesion rupture. We demonstrate that TE is highly sensitive to ONOOH, with this resulting in extensive dimerization, fragmentation and nitration of Tyr residues to give 3-nitrotyrosine (3-nitroTyr). This occurs with equimolar or greater levels of oxidant and increases in a dose-dependent manner. Quantification of Tyr loss and 3-nitroTyr formation indicates extensive Tyr modification with up to two modified Tyr per protein molecule, and up to 8% conversion of initial ONOOH to 3-nitroTyr. These effects were modulated by bicarbonate, an alternative target for ONOOH. Inter- and intra-protein di-tyrosine cross-links have been characterized by mass spectrometry. Examination of human atherosclerotic lesions shows colocalization of 3-nitroTyr with elastin epitopes, consistent with TE or elastin modification in vivo, and also an association of 3-nitroTyr containing proteins and elastin with lipid deposits. These data suggest that exposure of TE to ONOOH gives marked chemical and structural changes to TE and altered matrix assembly, and that such damage accumulates in human arterial tissue during the development of atherosclerosis.

Topics: Arteries; Atherosclerosis; Cadaver; Elastin; Extracellular Matrix; Humans; Immunohistochemistry; Inflammation; Macrophages; Nitro Compounds; Oxidation-Reduction; Peroxynitrous Acid; Protein Conformation; Tropoelastin; Tyrosine; Unfolded Protein Response

The epiglottis may contribute to upper airway obstruction in approximately 10% of patients with obstructive sleep apnea. Clinical experience indicates that older patients may be more likely to have epiglottis-related obstruction. This study was designed to examine tissue characteristics of the hyoepiglottic ligament as a possible factor in epiglottis-related obstruction based on previous research suggesting that older adults have fewer collagen, elastin, and muscle fibers in the hyoepiglottic ligament.. This is a cross-sectional study of 25 human cadaver hyoepiglottic ligaments. Specimens were stained using Masson's trichrome and Picrosirius red for collagen fibers and with Verhoeff-Van Gieson for elastin fibers. Percentage of collagen and elastin fiber staining for each specimen was calculated and averaged over three regions of each ligament section. Regression analysis was used to determine the association between age, smoking history, and collagen and elastin composition of the hyoepiglottic ligament.. The average age of the specimens was 68.4 ± 15.1 years (range 30-90 years). Increasing age was associated with a lower percentage of collagen and elastin fibers. When accounting for tobacco use, each 1-year increase in age was associated with a 0.53% decrease in Masson's trichrome staining (P = 0.004), a 0.35% decrease in Picrosirius red staining (P = 0.023), and a 0.33% decrease in Verhoeff-Van Gieson staining (P = 0.008).. Increasing age is associated with decreases in the collagen and elastin content of the hyoepiglottic ligament.. NA. Laryngoscope, 128:1245-1248, 2018.

Topics: Adult; Aged; Aged, 80 and over; Aging; Cadaver; Collagen; Cross-Sectional Studies; Elastin; Epiglottis; Humans; Ligaments; Middle Aged; Staining and Labeling

After menopause, decreased levels of estrogen and progesterone remodel the collagen of the soft tissues thereby reducing their stiffness. Stress urinary incontinence is associated with involuntary urine leakage due to pathological movement of the pelvic organs resulting from lax suspension system, fasciae, and ligaments. This study compares the changes in the orientation and position of the female pelvic organs due to weakened fasciae, ligaments, and their combined laxity. A mixture theory weighted by respective volume fraction of elastin-collagen fibre compound (5%), adipose tissue (85%), and smooth muscle (5%) is adopted to characterize the mechanical behaviour of the fascia. The load carrying response (other than the functional response to the pelvic organs) of each fascia component, pelvic organs, muscles, and ligaments are assumed to be isotropic, hyperelastic, and incompressible. Finite element simulations are conducted during Valsalva manoeuvre with weakened tissues modelled by reduced tissue stiffness. A significant dislocation of the urethrovesical junction is observed due to weakness of the fascia (13.89 mm) compared to the ligaments (5.47 mm). The dynamics of the pelvic floor observed in this study during Valsalva manoeuvre is associated with urethral-bladder hypermobility, greater levator plate angulation, and positive Q-tip test which are observed in incontinent females.

Topics: Adipose Tissue; Aged; Algorithms; Cadaver; Collagen; Computer Simulation; Connective Tissue; Elasticity; Elastin; Female; Finite Element Analysis; Humans; Ligaments; Models, Statistical; Movement; Muscle, Smooth; Pelvic Floor; Postmenopause; Urinary Bladder; Urinary Incontinence; Valsalva Maneuver

Arterial wall tissues are sensitive to their mechanical surroundings and remodel their structure and mechanical properties when subjected to mechanical stimuli such as increased arterial pressure. Such remodeling is evident in hypertension and aging. Aging is characterized by stiffening of the artery wall which is assigned to disturbed elastin function and increased collagen content. To better understand and provide new insight on microstructural changes induced by aging, the lamellar model of the aortic media was utilized to characterize and compare wall structure and mechanical behavior of the young and old human thoracic aortic samples. Such model regards arterial media as two sets of alternating concentric layers, namely sheets of elastin and interlamellar layers. Histological and biaxial tests were performed and microstructural features and stress-strain curves of media were evaluated in young and old age groups. Then using optimization algorithms and hyperelastic constitutive equations the stress-strain curves of layers were evaluated for both age groups. Results indicated slight elevation in the volume fraction of interlamellar layer among old subjects most probably due to age related collagen deposition. Aging indicated substantial stiffening of interlamellar layers accompanied by noticeable softening of elastic lamellae. The general significant stiffening of old samples were attributed to both increase of volume fraction of interlamellar layers and earlier recruitment of collagen fibers during load bearing due to functional loss of elastin within wall lamellae. Mechanical characterization of lamellar structure of wall media is beneficial in study of arterial remodeling in response to alternated mechanical environment in aging and clinical conditions through coupling of wall microstructure and mechanical behavior.

Topics: Adult; Age Factors; Aged; Aorta, Thoracic; Biomechanical Phenomena; Cadaver; Collagen; Elastin; Humans; Middle Aged; Stress, Mechanical; Vascular Stiffness; Young Adult

Human supraspinatus tendon (SST) exhibits region-specific nonlinear mechanical properties under tension, which have been attributed to its complex multiaxial physiological loading environment. However, the mechanical response and underlying multiscale mechanism regulating SST behavior under other loading scenarios are poorly understood. Furthermore, little is known about the contribution of elastin to tendon mechanics. We hypothesized that (1) SST exhibits region-specific shear mechanical properties, (2) fiber sliding is the predominant mode of local matrix deformation in SST in shear, and (3) elastin helps maintain SST mechanical integrity by facilitating force transfer among collagen fibers. Through the use of biomechanical testing and multiphoton microscopy, we measured the multiscale mechanical behavior of human SST in shear before and after elastase treatment. Three distinct SST regions showed similar stresses and microscale deformation. Collagen fiber reorganization and sliding were physical mechanisms observed as the SST response to shear loading. Measures of microscale deformation were highly variable, likely due to a high degree of extracellular matrix heterogeneity. After elastase treatment, tendon exhibited significantly decreased stresses under shear loading, particularly at low strains. These results show that elastin contributes to tendon mechanics in shear, further complementing our understanding of multiscale tendon structure-function relationships.

Topics: Aged; Aged, 80 and over; Animals; Biomechanical Phenomena; Cadaver; Cattle; Collagen; Elastin; Extracellular Matrix; Humans; Middle Aged; Pancreatic Elastase; Stress, Mechanical; Tendons

To investigate the architecture and distribution of collagen and elastin in human limbal conjunctiva, Tenon's capsule, and sclera.. The limbal conjunctiva, Tenon's capsule, and sclera of human donor corneal buttons were imaged with an inverted two-photon excited fluorescence microscope. No fixation process was necessary. The laser (Ti:sapphire) was tuned at 850 nm for two-photon excitation. Backscatter signals of second harmonic generation (SHG) and autofluorescence (AF) were collected through a 425/30-nm and a 525/45-nm emission filter, respectively. Multiple, consecutive, and overlapping (z-stack) images were acquired. Collagen signals were collected with SHG, whereas elastin signals were collected with AF.. The size and density of collagen bundles varied widely depending on depth: increasing from conjunctiva to sclera. In superficial image planes, collagen bundles were <10 μm in width, in a loose, disorganized arrangement. In deeper image planes (episclera and superficial sclera), collagen bundles were thicker (near 100 μm in width) and densely packed. Comparatively, elastin fibers were thinner and sparse. The orientation of elastin fibers was independent of collagen fibers in superficial layers; but in deep sclera, elastin fibers wove through collagen interbundle gaps. At the limbus, both collagen and elastin fibers were relatively compact and were distributed perpendicular to the limbal annulus.. Two-photon excited fluorescence microscopy has enabled us to understand in greater detail the collagen and elastin architecture of the human limbal conjunctiva, Tenon's capsule, and sclera.

Topics: Adult; Aged; Cadaver; Collagen; Conjunctiva; Elastin; Female; Humans; Imaging, Three-Dimensional; Male; Microscopy, Fluorescence, Multiphoton; Middle Aged; Reproducibility of Results; Sclera; Tenon Capsule

Precise location of IL-18 in cell and tissue elements of the atherosclerotic lesions in humans and its role in destabilization of the atherosclerotic plaque were detected. The data suggested a hypothesis on indirect involvement of IL-18 in destruction of the elastic and collagen fibers in an unstable plaque due to this cytokine capacity to induce the production of IFN-γ in T cells and macrophages, this eventually leading to inhibition of collagen and elastin synthesis in smooth muscle cells of the vascular wall and to loosening of the plaque cap.

Topics: Aged; Aorta; Azo Compounds; Cadaver; Collagen; Elastin; Humans; Immunohistochemistry; Interferon-gamma; Interleukin-18; Macrophages; Male; Middle Aged; Myocytes, Smooth Muscle; Plaque, Atherosclerotic; T-Lymphocytes

In the human middle ear, the annular ligament of the incudostapedial joint and the insertions of the tensor tympani and stapedius muscles contain abundant elastic fibers; i.e., the elastic-fiber-mediated entheses. Hyaluronan also coexists with the elastic fibers. In the present study using immunohistochemistry, we demonstrated the distribution of elastin not only in the incudostapedial joint but also in the other two joints of the middle ear in adults and fetuses. In adults, the expression of elastin did not extend out of the annular ligament composed of mature elastic fibers but clearly overlapped with it. Electron microscopic observations of the annular ligament demonstrated a few microfibrils along the elastic fibers. Thus, in contrast to the vocal cord, the middle ear entheses seemed not to contain elaunin and oxytalan fibers. In mid-term fetuses (at approximately 15-16 weeks of gestation) before opening of the external acoustic meatus, the incudostapedial joint showed abundant elastic fibers, but the incudomalleolar and stapediovestibular joints did not. At this stage, hyaluronan was not colocalized, but distributed diffusely in loose mesenchymal tissues surrounding the ear ossicles. Therefore, fetal development of elastin and elastic fibers in the middle ear entheses is unlikely to require acoustic oscillation. In late-stage fetuses (25-30 weeks), whose ear ossicles were almost the same size as those in adults, we observed bundling and branching of elastic fibers. However, hyaluronan expression was not as strong as in adults. Colocalization between elastic fibers and hyaluronan appeared to be a result of postnatal maturation of the entheses.

Topics: Aged; Aged, 80 and over; Cadaver; Ear, Middle; Elastin; Female; Fetal Development; Humans; Immunohistochemistry; Incus; Joints; Ligaments; Male; Malleus; Microscopy, Electron, Transmission; Pregnancy; Stapes; Tendons

Topics: Biomechanical Phenomena; Cadaver; Collagen; Elastin; Humans; Liver; Microscopy; Tensile Strength; Weight-Bearing

The purpose of this work was to apply nonlinear laser scanning microscopy (NLSM) for visualizing the morphology of extracellular matrix proteins within human vocal folds. This technique may potentially assist clinicians in making rapid diagnoses of vocal fold tissue disease or damage. Microstructural characterization based on NLSM provides valuable information for better understanding molecular mechanisms and tissue structure.. Experimental, ex vivo human vocal fold.. A custom-built multimodal nonlinear laser scanning microscope was used to scan fibrillar proteins in three 4% formaldehyde-fixed cadaveric samples. Collagen and elastin, key extracellular matrix proteins in the vocal fold lamina propria, were imaged by two nonlinear microscopy modalities: second harmonic generation (SHG) and two-photon fluorescence (TPF), respectively. An experimental protocol was introduced to characterize the geometrical properties of the imaged fibrous proteins.. NLSM revealed the biomorphology of the human vocal fold fibrous proteins. No photobleaching was observed for the incident laser power of ∼60 mW before the excitation objective. Types I and III fibrillar collagen were imaged without label in the tissue by intrinsic SHG. Imaging while rotating the incident laser light-polarization direction confirmed a helical shape for the collagen fibers. The amplitude, periodicity, and overall orientation were then computed for the helically distributed collagen network. The elastin network was simultaneously imaged via TPF and found to have a basket-like structure. In some regions, particularly close to the epithelium, colocalization of both extracellular matrix components were observed.. A benchmark study is presented for quantitative real-time, ex vivo, NLSM imaging of the extracellular macromolecules in human vocal fold lamina propria. The results are promising for clinical applications.

Topics: Aged; Cadaver; Collagen; Elastin; Extracellular Matrix; Female; Humans; Male; Microscopy, Confocal; Vocal Cords

Normal human vocal fold fibroblast (hVFF) primary cell lines are unavailable commercially and are very difficult to acquire, subsequently little is known about their characteristics. The purpose of this study was to compare the morphological and proliferation characteristics and gene expression of hVFFs from different aged donors.. In vitro.. We developed three normal hVFF primary cell lines from donors aged 21 (21T), 59 (59T) and 79 (79T) years. We characterized their morphological features, proliferative abilities, telomere lengths, and their functional gene expression by quantitative real-time PCR.. The 21T line maintained a typical spindle shape until passage 14 whereas 59T and 79T changed morphology to wider, shorter cells at passage 7. Proliferation rates were constant for the 21T through passage 14; 59T's proliferative half-life was passage 9, whereas 79T maintained lower proliferation rates from passage 4. Gene expression levels for fibronectin, collagen I, collagen VI, procollagen I and elastin demonstrated similar patterns for all lines, however, relative amounts decreased with the age of donor. Telomere lengths did not show differences related with donor age.. hVFF primary cultures have limited proliferative capacity. The morphology, proliferation, differentiation, and gene expression levels of VFF can be affected by age, but senescence patterns were similar across the ages.

Topics: Adult; Aged; Aging; Cadaver; Cell Differentiation; Cell Proliferation; Cells, Cultured; Collagen; Elastin; Female; Fibroblasts; Fibronectins; Gene Expression; Humans; Male; Middle Aged; Polymerase Chain Reaction; Reference Values; RNA; Telomere; Vocal Cords

The annulus fibrosus of the intervertebral disc is comprised of concentric lamella of oriented collagen fibers embedded in a hydrated proteoglycan matrix with smaller amounts of minor collagens, elastin, and small proteoglycans. Its structure and composition enable the disc to withstand complex loads and result in inhomogeneous, anisotropic, and nonlinear mechanical behaviors. The specific contributions of the annulus fibrosus constituent structures to mechanical function remain unclear. Therefore, the objective of this study was to use a structurally motivated, anisotropic, nonlinear strain energy model of annulus fibrosus to determine the relative contributions of its structural components to tissue mechanical behavior. A nonlinear, orthotropic hyperelastic model was developed for the annulus fibrosus. Terms to describe fibers, matrix, and interactions between annulus fibrosus structures (shear and normal to the fiber directions) were explicitly included. The contributions of these structures were analyzed by including or removing terms and determining the effect on the fit to multidimensional experimental data. Correlation between experimental and model-predicted stress, a Bland-Altman analysis of bias and standard deviation of residuals, and the contribution of structural terms to overall tissue stress were calculated. Both shear and normal interaction terms were necessary to accurately model multidimensional behavior. Inclusion of shear interactions more accurately described annulus fibrosus nonlinearity. Fiber stretch and shear interactions dominated contributions to circumferential direction stress, while normal and shear interactions dominated axial stress. The results suggest that interactions between fibers and matrix, perhaps facilitated by crosslinks, elastin, or minor collagens, augment traditional (i.e., fiber-uncrimping) models of nonlinearity.

Topics: Anisotropy; Biomechanical Phenomena; Cadaver; Collagen; Elasticity; Elastin; Humans; Intervertebral Disc; Models, Biological; Models, Theoretical; Nonlinear Dynamics; Proteoglycans; Stress, Mechanical

The collagen subtypes in human vocal folds are of particular interest, because each collagen subtype has different features that make it uniquely suited for performing specific tissue tasks and each collagen subtype can affect the tissue properties of the vocal fold lamina propria.. Human vocal folds from 5 autopsy cases (less than 65 years old) were examined by immunohistochemistry for collagen types I, III, IV, and V and elastin.. Collagen type III was distributed throughout the whole lamina propria. Type I was found just beneath the basal membrane, in the deep layer of the lamina propria and in the anterior and posterior maculae flavae. Types IV and V were present in the epithelial and endothelial basal membrane. Three-dimensional images from thick specimens reconstructed with confocal microscopy showed 2 distinct patterns: type III fibers were wavy, collagenous fibers, as previously observed in the vocal folds, and type I fibers were thinner than type III fibers. These results suggest that type III fibers help maintain the lamina propria structure and that type I fibers provide the tensile strength required around the basal membrane and vocal ligament to maintain the vocal fold shape while withstanding vibratory forces.

Topics: Adult; Biomarkers; Cadaver; Collagen Type I; Collagen Type III; Elastin; Female; Humans; Immunohistochemistry; In Vitro Techniques; Male; Microscopy, Confocal; Middle Aged; Procollagen; Vocal Cords

Heart disease is directly associated with aging as well as progression of atherosclerosis. The vessels begin to stiffen with age. It is speculated that the increase in stiffness can occur as a result of either increase progression of atherosclerosis or possibly due to the deterioration of the elastic components of the arterial wall. Regardless of the mechanism, an increase in vessel stiffness can lead to significant increase in the pathophysiological progression of the disease. The overall objectives of this investigation were to evaluate the coronary artery obtained from cadavers in their 7th, 8th and 9th of life and characterized the level of atherosclerosis and to identify using special elastin staining techniques the involvement of fiber disruption in atherosclerosis. The coronary arteries were obtained from cadaveric donors at the University of Saskatoon (average age 81.7 years, range 77-92 years of age). The arteries were fixed, sectioned and stained for routine analysis as well as with an Elastin staining protocol. The arteries were screened and the level of atherosclerosis was measured as well as thickness changes within the arteries. Digital imaging was used to capture the areas of elastin disruption. The overall results suggest elastin disruption occurs as the atherosclerotic plaque progresses. The imaging system in conjunction with elastin staining allows for a very sensitive method to analyze the tissue for the progression of pathophysiological disease mechanisms.

Topics: Aged; Aged, 80 and over; Aging; Arteries; Cadaver; Coronary Artery Disease; Coronary Vessels; Elastin; Female; Humans; Image Enhancement; Male; Microscopy

The purpose of this study was to determine the structure and composition of the forearm interosseous membrane (IOM).. The IOM of 12 cadaver forearms was fixed in formalin. After fixation 5 individual IOM fiber bundles per arm were separated by dissection, excised, and processed with hematoxylin-eosin, trichrome, and Verhoff-vanGeison stains. Nine additional fresh forearms were dissected and 5 IOM fiber bundles per arm were analyzed using the hydroxyproline assay. Bundles were evaluated at ulnar, central, and radial locations.. Histologic analysis of the IOM bundles obtained from the 12 fixed forearms showed an abundance of collagen in the main bundle central location (84% +/- 7.8%). A progressive increase in collagen was noted from distal to proximal bundles (r =.72). The hydroxyproline assay of collagen content of the main IOM bundle's central location from the 9 additional fresh forearms was 99.3% +/- 16.5%. There was no difference between bundles or location (power = 0.25 and 0.46).. We found that the IOM possesses a large collagen content arranged in fibrillar structures surrounded by elastin. Collagen was abundant in the proximal bundles and decreased in the distal bundles.

Topics: Aged; Aged, 80 and over; Cadaver; Collagen; Dissection; Elastin; Forearm; Humans; Membranes; Middle Aged; Radius; Ulna

Solidity and elasticity are the two main biomechanical properties of pelvic tissues involved in surgical cure of genital prolapse-prevertebral, pectinate, and sacrospinal ligaments, tendinous arcs of the pelvic fascia, vaginal tissue. We report data in the literature and personal studies concerning these autologous biological tissues.. The resistance of pelvic tissues was tested on 29 cadavers. Measurements were also made on two 2-cm samples of vaginal tissue obtained during vaginal route surgery for prolapse cure in 20 menopaused women. Stress tests were conducted to determine resistance and level of rupture.. There was a wide variability in ligament resistance, ranging from a minimum of 22 Newtons to a maximum to the order of 200 Newtons. Results varied greatly from one woman to another and also between the two sides in the same woman. The prevertebral ligament exhibited the greatest resistance. The pectinate ligament was significantly more resistant than the sacrospinal ligaments and the tendinous arcs of the pelvic fascia. There was a significant relationship between the subjective assessment of ligament quality and objective measurements of resistance. For vaginal tissues, resistance varied greatly from 12 Newtons to a maximum to the order of 76 Newtons. Flexion values ranged from 14 to 130 Newtons.. Our findings illustrate pelvic tissue failure observed in patients with genital prolapse. Individual maximal resistance of the pelvic ligaments is vary variable, between ligaments and between subjects, and even between sides in a given subject. Pelvic ligaments used for cure of genital prolapse are moderately resistant with wide interindividual variability. The mechanical properties of vaginal tissue are also very variable, illustrating why these tissues may exhibit a certain resistance against dissociation when exposed to loading but much less resistance when exposed to traction by a surgical suture. These findings suggest a revision of classical surgical procedures.

Topics: Age Factors; Aged; Biomechanical Phenomena; Cadaver; Cicatrix; Collagen; Elasticity; Elastin; Fascia; Female; Humans; Ligaments; Middle Aged; Patient Selection; Prostheses and Implants; Stress, Mechanical; Sutures; Uterine Prolapse; Vagina

To evaluate whether decreased signal intensity on T(1) weighted MR images of the retrodiscal tissue of the temporomandibular joint (TMJ) reflects increased density of collagen fibres.. Corrected sagittal T(1) weighted MR images of six TMJs from six fresh cadavers (three males and three females; age range 76-87 years, mean 80.8 years) were obtained. Following MRI, slices of tissue samples were taken from the cadavers that exactly matched the planes of the MR image. These samples were fixed, decalcified and stained (haematoxylin-eosin stain, Elastica van Gieson's stain) for light microscopy. The samples were evaluated for density of collagen fibres according to Hall et al (1984) and for vascularity, arterial wall thickness, fat content and elastin. In these sagittal samples, the retrodiscal tissue was divided anteroposteriorly and vertically into six areas and each area was classified by histological parameters. The MR images were similarly divided into six areas. Areas with reduced signal intensity were classified as the low signal group and those with no reduced signals were classified as the control group.. Collagen density assessed histologically differed between the low signal intensity group and the control group, and loose collage density on the histological samples was observed significantly more often in the low signal group (Fisher's exact test, P=0.03). There were no statistically significant differences in the other categories between the two groups.. The results suggest that reduced T1 signals of retrodiscal tissue do not necessarily reflect a dense distribution of collagen fibres.

Topics: Aged; Aged, 80 and over; Arteries; Cadaver; Collagen; Coloring Agents; Elastin; Female; Fibrillar Collagens; Humans; Image Enhancement; Lipids; Magnetic Resonance Imaging; Male; Temporomandibular Joint; Temporomandibular Joint Disc

1. To evaluate the effectiveness of the main elastic tissue staining methods in a. basilaris. 2. To study the arrangement of elastic fibers in human a. basilaris wall.. For anatomical material we used a. basilaris removed from cadavers of ten people who died from violent death, their age ranging from 21 to 30 years. We studied histological structure staining by Hematoxylin-Eosin, Orcein, Gomori and Van Gieson methods. The samples were examined under the microscope "Zeiss-Standart 25" and photographed with a MC80DX photocamera.. The internal elastic lamina was distinctly seen while staining by Hematoxylin-Eosin, Orcein, Gomori and Van Gieson methods. The elastic fibers and muscle cells of the middle layer were hardly distinguished. We found collagen fibers and several elastic fibers in the external layer of the vascular wall. We studied the arrangement of elastic fibers in medial and cranial segments of human a. basilaris wall.. Several staining methods have to be provided to differentiate the elastic fibers from collagen fibers and muscle cells in the best way, because only complex staining enables to differentiate one from another. Human a. basilaris has a mixed elastic-muscular structure. The elastic tissue distributes gradually in medial and cranial segments of a. basilaris medial layer. There is thin, sharp, solid and undulate internal elastic lamina in the internal layer. There are elastic fibers, smooth muscle cells and several collagen fibers in the middle layer of the vessel. The external layer of a. basilaris consists of several elastic fibers and the main part is occupied by collagen fibers.

Topics: Adult; Basilar Artery; Cadaver; Collagen; Elastic Tissue; Elastin; Histological Techniques; Humans; Male; Microscopy; Muscle, Smooth, Vascular; Staining and Labeling

Vulnerable plaque generally contains a thin fibrous cap, lipid pools, and reduced internal plaque collagen. Arterial fluorescence analysis can differentiate atherosclerotic lesions from normal arteries; however, the contribution of the lipid core to atherosclerotic arterial fluorescence remains controversial. This study aimed to identify lipid core fluorophores and to differentiate the lipid core from normal artery and atheroma. The helium-cadmium laser-induced fluorescence spectra of cadaveric arteries and known chemical constituents were recorded. Lipid core fluorescence spectra exhibited marked red shifts and broadening compared with the fluorescence spectra of normal tissue and atheroma. Similar fluorescence spectra were obtained for lipid core and oxidized low density lipoprotein, for atheroma and collagen, and for normal artery and elastin. A classification based on collagen, elastin, and oxidized low density lipoprotein spectral decomposition could discriminate the lipid core (n=29), normal artery (n=74), atheroma (n=73), and preatheroma (n=10) with 86% accuracy. Fibrous cap thickness was correlated with the spectral collagen content index (r=0.65, P<0.0001), especially at a thickness of <200 microm. We conclude that a classification algorithm based on chemical spectral decomposition can accurately classify the fluorescence spectra of normal artery, atheroma, and lipid core and may be useful in identifying vulnerable atheroma in vivo.

Topics: Adult; Algorithms; Arterial Occlusive Diseases; Cadaver; Collagen; Coronary Artery Disease; Elastin; Femoral Artery; Humans; Lasers; Lipids; Lipoproteins, LDL; Microscopy, Fluorescence; Oxidation-Reduction

Central venous catheters (CVC) in the internal jugular vein have become an important adjunct to the overall management of intensive care patients, but their use is associated with frequent neck complications. In a review of the literature anatomical variation in size, form and function of the valve system of the internal vein was found.. This study macroscopically and microscopically investigates the anatomical variety of the vein valves of the inferior internal jugular vein.. 100 cadavers from legal autopsies were investigated. We selected 45 patients with an acute myocardial infarction death and a control group (55 patients) formed by different causes of death. The veins were prepared for light microscopic study, the specimens were serially sectioned (ca. 30 sections) and stained with hematoxylin and eosin.. Anatomical variety was observed predominantly unilateral on the right side of the internal jugular vein. The valves were often bicuspid at the right side (92%) and tricuspid on the left side (64%) and mostly located ca. 2 cm above the subclavia-jugularis bifurcation. In the histological study, a variability of the net of collagen and elastin fibres in the tunica intima and media was observed. The structure of the adventitia was constant. 18 patients with a jugular valve vein incompetence (age over 60) appeared to have thickening of the tuberculum in the sinus of the valve. The cups of the valves were found rudimentary in these patients with advanced stages of tricuspid incompetence.. The present study demonstrates the variety of the valves of the jugular vein. They play an important role to impede the retrograde flow during cardiopulmonary resuscitation as well as in jugular vein cannulation.

Topics: Adolescent; Adult; Aged; Autopsy; Cadaver; Cause of Death; Child; Child, Preschool; Collagen; Coloring Agents; Elastin; Female; Humans; Infant; Infant, Newborn; Jugular Veins; Male; Middle Aged; Myocardial Infarction; Resuscitation; Tunica Intima; Tunica Media

A new surgical technique has been recently described that involves reconstruction of the dorsal aspect of the scapholunate ligament (DSLL) with a bone-retinaculum-bone (BRB) autograft preparation from Lister's tubercle. In this study, the mechanic and histologic properties of the 2 tissues were compared. The BRB and DSLL specimens were harvested from 6 fresh-frozen human cadaveric forearms. The specimens were measured and then tested in tension with an MTS 810 servohydraulic materials testing machine at a rate of 10 mm/min. The BRB autograft was significantly weaker than the DSLL. However, because the mean cross-sectional area of the DSLL was more than 3 times as large as that of the BRB autograft, the failure stress (failure force/cross-sectional area) of the BRB autograft was not significantly different from that of the DSLL. Histologically, the DSLL and BRB autograft were also similar. These findings suggest that the BRB autograft may be appropriate graft material for scapholunate ligament reconstruction, but that structural parity with DSLL will ultimately depend on remodeling and hypertrophy during healing. This also highlights the importance of using a large BRB autograft to approximate the strength of the DSLL as much as possible, and that the BRB autograft must be protected postoperatively as it heals and remodels.

Topics: Aged; Anatomy, Cross-Sectional; Biomechanical Phenomena; Bone Remodeling; Bone Transplantation; Cadaver; Carpal Bones; Collagen; Connective Tissue; Elastin; Fascia; Humans; Hypertrophy; Ligaments, Articular; Lunate Bone; Male; Middle Aged; Pliability; Stress, Mechanical; Transplantation, Autologous; Wound Healing

This study was designed to evaluate the characteristics of human orbital fat and connective tissue. Two exenteration specimens were studied by light microscopy with special stains. Four distinct regions were identified on the basis of their connective tissue septa, which contained blood vessels and were composed of elastin and collagen types I, III, and IV. Transmission electron microscopy was performed on the opposite orbits. The fibroblasts and adipocytes appeared metabolically inactive and showed no regional differences. The fat was phase extracted from the connective tissue and subjected to biochemical analysis. No regional differences were found in the content of fatty acids and protein. The fatty acids included palmitic acid (22-24.6%), oleic acid (45-51.5%), and linoleic acid (15-18.6%). Despite demarcation of the orbital fat into distinct regions by the connective tissue septa, ultrastructural and biochemical analysis revealed no regional variations in the fat. The diagnostic and therapeutic implications of these findings are discussed.

Topics: Adipose Tissue; Adult; Cadaver; Chromatography, High Pressure Liquid; Collagen; Connective Tissue; Elastin; Electrophoresis, Polyacrylamide Gel; Fatty Acids; Humans; Immunoenzyme Techniques; Oculomotor Muscles; Orbit

The second annular pulley and underlying flexor tendons from 15 fresh frozen fingers were prepared, sectioned transversely and longitudinally and then stained with hematoxylin-eosin, Verhoeff-Van Gieson (Elastin), Masson's trichrome and for the presence of hyaluronic acid. Three discrete layers of the second annular pulley were identified (1) an outer layer, continuous with the membranous sheath, that was richly vascularized; (2) a middle layer, characterized by radially oriented collagen fibrils and significant elastin fibrils; (3) an inner gliding surface, characterized by longitudinally oriented collagen fibrils and modified fibroblasts secreting hyaluronic acid. The three layers of the pulley seem specialized and have developed based on the functional requirements of the pulley apparatus. The outer layer serves as a source of vascular supply and nutrition, the middle layer maintains structural integrity and is organized to efficiently resist flexor tendon bowstringing, and the innermost layer facilitates efficient excursion of the underlying flexor tendons both by the orientation of the collagen fibers and by the secretion of substances that are thought to minimize friction.

Topics: Cadaver; Collagen; Elastin; Fingers; Humans; Hyaluronic Acid; Staining and Labeling; Synovial Membrane; Tendons

A histologic and biochemical study of elastin in the posterior longitudinal ligament and spinal dura was performed using autopsy cadavers.. To provide a rationale for resiliency of the PLL and the spinal dura.. Among the spinal ligaments, the nuchal ligament and the ligamentum flavum have a very high elastin content, and some biochemical and morphologic studies of these ligaments have been published. No reports on the elastin content in the posterior longitudinal ligament or spinal dura have been published.. Specimens of the posterior longitudinal ligament and the dura collected from three cadavers were studied histologically. For quantitative analysis of elastin and collagen, the posterior longitudinal ligament specimens were collected from 22 cadavers and the dura specimens from 20 cadavers. Elastin was extracted using the hot alkali method of Lansing et al.. The elastic fibers in the posterior longitudinal ligament generally were arranged parallel in the cephalocaudal direction, whereas the fibers in the spinal dura had a more multidirectional arrangement. The elastin content of the posterior longitudinal ligament averaged 7.3% of the total dry weight and that of the spinal dura was 7.1% for the ventral aspect and 13.8% for the dorsal aspect. The elastin content of the spinal dura was about two times higher in all dorsal specimens than in the corresponding ventral specimens. The elastin content of the lower thoracic region was higher than that of any other region. The amino acid composition of the elastin in the posterior longitudinal ligament and spinal dura was similar to that previously determined in other spinal ligaments.

Topics: Aged; Aged, 80 and over; Amino Acids; Cadaver; Collagen; Dura Mater; Elastic Tissue; Elastin; Female; Humans; Longitudinal Ligaments; Male; Spinal Cord

Topics: Cadaver; Collagen; Elastin; Histocytochemistry; Humans; Muscles; Proteins; Varicose Veins; Vascular Surgical Procedures