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PubMed1985

Elastosis in relation to prognosis in primary breast carcinoma.

The content of elastic tissue has been evaluated in 171 primary breast carcinomas. Of the tumors, 35% had no or very little elastic tissue in the malignant areas, 42% presented with medium elastosis, and 22% had gross elastosis. The occurrence of elastin has been related to different prognostic factors. An increasing amount of elastin was found with increasing amounts of estrogen receptor (p = 0.0003), while there was only a slight correlation to the progesterone receptor content. Furthermore, the highly differentiated tumors contained more elastin in their tumor tissue than the poorly differentiated tumors (p = 0.003), and parous women had significantly more elastin than nonparous women (p = 0.02). The presence of elastin was not, however, of any demonstrable prognostic significance.

Breast Neoplasms↗

PubMed2004

Tumefactive lipedema with pseudoxanthoma elasticum-like microscopic changes.

BACKGROUND: Lipedema is a condition characterized by diffuse, bilaterally symmetrical, painful swelling of the legs and buttocks. Microscopically, there are dermal and septal edema, adipocyte degeneration, and numerous mast cells, features held in common with lipedematous alopecia. CASE REPORT: We present the case of a 60-year-old woman with a long history of bilateral leg masses with microscopic features of lipedema. In addition, elastic-fiber changes typical of pseudoxanthoma elasticum (PXE) were discovered within the subcutaneous septa in three separate specimens obtained from an affected extremity. The patient did not have other clinical findings of PXE, although there was a history of both hypertension and congestive heart failure. CONCLUSION: This tumefactive presentation of lipedema has not been previously described. Regarding the elastic-tissue abnormalities, the patient could have either a subclinical form of PXE, perhaps predisposing to lipedema, or secondary elastic-tissue changes resulting from the massive edema. If the latter is the case, then this could represent an unusual manifestation of localized acquired cutaneous PXE (calcific elastosis).

Adipose Tissue↗

PubMed2001

Moment dependency of the series elastic stiffness in the human plantar flexors measured in vivo.

The moment dependency of the series elastic stiffness (SES) in the human plantar flexors was investigated in vivo with the quick release method. At an ankle moment of 100 N m produced with either voluntary or electrical stimulation we found non-significantly different SES of 506+/-72 and 529+/-125 N m rad(-1), respectively. It has recently been proposed that the amount of series elastic tissue involved in plantar flexion changes with the moment level produced by the plantar flexors (Hof, J. Biomech 31 (1998) 793). However, our results indicate that the amount of series elastic tissue involved in plantar flexions remained constant with changing moment levels. We therefore propose that the series elastic component (SEC) in human plantar flexors act as one structure or rather one combination of anatomical structures which is engaged at all muscle activation levels, and that the mechanical properties (i.e. the stress-strain function) are determined by the combined tissue mechanical properties. Additionally, our results demonstrated that the SES in the human plantar flexors at moments levels up to about isometric maximum did not reach an asymptote where the stiffness is independent of moment, i.e. SEC of the plantar flexors is, during many daily activities, loaded for the greatest part in the non-linear part of the stress-strain function.

Adult↗

PubMed2001

Musculo-tendinous and joint elastic characteristics during elbow flexion in children.

OBJECTIVE: The aim of the present research was to determine joint stiffness and musculo-tendinous stiffness in children. BACKGROUND: No reliable data was available on differences in such parameters when comparing children and adults. METHODS: Sinusoidal perturbations and quick-released movements were applied to the right elbow during flexion to determine joint stiffness and musculo-tendinous stiffness, respectively. For normalization purposes, stiffness indexes were calculated as the slope of the relationship between stiffness and torque. RESULTS: Main results were that musculo-tendinous stiffness indexes obtained in children were similar to adult data deduced from the literature. On the other hand, joint stiffness indexes obtained in children were in the range 0.9-3.8 rad(-1) and were lower than those reported in the literature for adults (between 4 and 8.5 rad(-1)). CONCLUSION: Since normalized musculo-tendinous stiffness is similar in children and in adults, it can be hypothesized that, during growth, increase in ability to produce force parallels elastic tissue development. RELEVANCE: Stiffness parameters could be used, in the context of other functional tests, to characterize changes in muscle properties in neuromuscular disorders when elastic tissues are supposed to be altered.

Adolescent↗

PubMed1999

Relationship between myocardial tissue density measured by microgravimetry and sound speed measured by acoustic microscopy.

If myocardial tissue can be assumed to be fluid-like, myocardial tissue elasticity can be estimated by the sound speed of tissue based on the equation K = rho(c)2, where K is the elastic bulk modulus, rho is density, and c is the sound speed of tissue. However, little data exist regarding the relationship between the sound speed of tissue and tissue density. The purpose of the present study was to evaluate the relationship between the sound speed of tissue and tissue density of various diseased myocardia. Myocardial tissue specimens at autopsy were obtained from 10 control patients without cardiovascular disease, 8 patients with pressure overload left ventricular hypertrophy (POLVH), and 8 patients with cardiac amyloidosis (AMD). Myocardial tissue sound speed was measured using a scanning acoustic microscope operating in the frequency of 450 MHz, and tissue density was measured by microgravimetry. The sound speed in POLVH (1639 +/- 17 m/s) was higher and that in AMD (1565 +/- 11 m/s) was lower than that in control patients (1615 +/- 15 m/s) (p < 0.001) at the temperature of 20-22 degrees C. The density in POLVH (1.087 +/- 0.004 g/cm3) was higher and that in AMD (1.072 +/- 0.003 g/cm3) was lower than that in control patients (1.082 +/- 0.003 g/cm3) (p < 0.001). Tissue density correlated with sound speed in all three groups (r = 0.96, p < 0.001). Therefore, myocardial tissue sound speed data obtained by acoustic microscopy enabled us to evaluate tissue elasticity without measuring tissue density directly.

Acoustics↗

PubMedDate not supplied

Clefts in intradermal nevi: an ultrastructural study.

Six intradermal melanocytic nevi, two with and four without intercellular slitlike spaces, were examined by light microscopy and electron microscopy of deparaffinized tissue. The spaces were partially lined by elongated nevus cells and contained a few collagen fibrils. Other features in both groups included an abundance of (1) immature elastic tissue comprised of aggregates of microfibrils lacking an amorphous component and (2) collagen fibrils that were finer than in normal dermis and did not form compact bundles. We propose that these elastic tissue and collagen fiber changes diminish the resistance of the dermis to the mechanical stress of the biopsy procedure and histologic processing, resulting in the formation of artifactual clefts.

Adult↗

PubMed1996

Fluorescence and confocal laser scanning microscopy imaging of elastic fibers in hematoxylin-eosin stained sections.

We have studied the possibility of associating fluorescence microscopy and hematoxylin-eosin staining for the identification of elastic fibers in elastin-rich tissues. Elastic fibers and elastic laminae were consistently identified by the proposed procedure, which revealed itself to be easy and useful for the determination of such structures and their distribution. The fluorescence properties of stained elastic fibers are due to eosin staining as revealed by fluorescence analysis of the dye in solution, with no or only minor contribution by the elastin auto-fluorescence. The main advantage of this technique resides in the possibility of studying the distribution of elastic fibers in file material without further sectioning and staining. The use of the confocal laser scanning microscope greatly improved the resolution and selectivity of imaging elastic fibers in different tissues. The determination of the three-dimensional distribution and structure of elastic fiber and laminae using the confocal laser scanning microscope was evaluated and also produced excellent results. used to discriminate calcified bone and elastic fibers using the fluorescence microscope (Bradbeer et al. 1994). The selective fluorescence exhibited by these two main tissue components is based on the very faint eosin staining, while intensely eosinophilic substrates and those stained with the highly absorbing basic dyes show no fluorescence or just a very faint signal. Considering the possibility of using eosin fluorescence for the selective identification of some tissue components, we have extended this approach to the study of elastic fibers in hematoxylin-eosin (H&E) preparations. This paper then describes the results of observations with the fluorescence microscope of some H&E stained sections and evaluates the use of the confocal laser scanning microscope to image elastic fibers in the same preparations. Furthermore, we have also studied absorption and fluorescence spectra of eosin and phloxine, a closely related dye, in solution, to correlate them with the fluorescence detected in tissue sections.

Animals↗

PubMed2005

Elastoderma of the neck in a teenage boy.

Elastoderma is an exceedingly rare condition characterized clinically as an acquired localized laxity of skin and, histologically, as an excessive accumulation of pleomorphic elastic structures within the dermis. We report the case of a 16-year-old white man with a 2-year history of progressive laxity, extensibility, and wrinkling of the skin localized to the anterior aspect of the neck. Histologic examination of specimens from the affected area showed dense aggregates of eosinophilic material present within the dermis. Transmission and scanning electron microscopic examination demonstrated apposition of abnormal elastic structures at the periphery of elastic tissue fibers, with grapelike globular structures. To our knowledge, we report the third case of elastoderma.

Adolescent↗

PubMed2002

Role of elastin-matrix interactions in tumor progression.

Data from the literature now indicate that cancer cells can specifically interact with the unique extracellular matrix protein, elastin. The interaction is mediated by two elastin-binding proteins (EBP), S-gal/EBP (organized into the elasin receptor/elastonectin complex) and galectin-3, components of two laminin receptors. Studies revealed that the expression of both EBPs is closely associated to the invasive/metastatic potential of various cancer types. This is due to the fact that elastin-ligation of S-gal/EBP induces motogenic, as well as mitogenic signals and releases various elastases from cancer cells and the induction depends on the metastatic potential. Studies also demonstrated that certain cancer cells can synthesize elastin and express lysyl oxydase, providing explanation for frequent appearance of elastic tissue in tumors such as breast or gastric cancers. Clinico-pathological data suggest some correlation with tumor progression of the presence of the elastic tumor stroma. Since elastic tissue may be a significant reservoir of angiostatic molecule(s) this extracellular matrix protein can also have a role in tumor-induced angiogenesis. Soluble elastin as well as elastin peptides are potent inhibitors of the metastatic process in experimental tumor models. On the other hand, elastin peptides can also be used to design targeted therapies exploiting the unique physicochemical nature of this matrix protein. Altogether, these data suggest a significant role for tumor cell-elastin interactions in tumor progression.

Animals↗

PubMed1978

Functional obstruction of the ureter and renal pelvis. A histological and electron microscopic study.

Histological, histochemical and electron microscopic techniques have been used to compare dilated and normal calibre segments of ureter and renal pelvis in cases of idiopathic hydronephrosis and primary obstructive megaureter. In both conditions a marked increase in collagen and elastic tissue occurs in the wall of the distended segment and this infiltration extends throughout the proximal dilated ureter and renal pelvis. Evidence is presented to show that in the dilated segment, smooth muscle cells are directly involved in the synthesis of connective tissue elements. These findings support the view that the primary anomaly in idiopathic hydronephrosis and primary obstructive megaureter can be attributed to a malfunction of smooth muscle cells in the ureter and renal pelvis. However, the possibility remains that the changes in smooth muscle are secondary and have been induced by obstruction and distension caused in these pathological conditions by unknown aetiological factors.

Cholinesterases↗

PubMed2005

Double-blinded, placebo-controlled trial of green tea extracts in the clinical and histologic appearance of photoaging skin.

BACKGROUND: Green tea extracts have gained popularity as ingredients in topical skin care preparations to treat aging skin. Green tea polyphenolic compounds have significant antioxidant and anti-inflammatory activities, and studies suggest that these extracts help mediate ultraviolet radiation damage. OBJECTIVE: To evaluate the effects of a combination regimen of topical and oral green tea supplementation on the clinical and histologic characteristics of photoaging. METHODS: Forty women with moderate photoaging were randomized to either a combination regimen of 10% green tea cream and 300 mg twice-daily green tea oral supplementation or a placebo regimen for 8 weeks. RESULTS: No significant differences in clinical grading were found between the green tea-treated and placebo groups, other than higher subjective scores of irritation in the green tea-treated group. Histologic grading of skin biopsies did show significant improvement in the elastic tissue content of treated specimens (p<.05). CONCLUSION: Participants treated with a combination regimen of topical and oral green tea showed histologic improvement in elastic tissue content. Green tea polyphenols have been postulated to protect human skin from the cutaneous signs of photoaging, but clinically significant changes could not be detected. Longer supplementation may be required for clinically observable improvements.

Administration, Oral↗

PubMed1993

Elastography: elasticity imaging using ultrasound with application to muscle and breast in vivo.

Changes in tissue elasticity are generally correlated with its pathological state. In many cases, despite the difference in elasticity, the small size of a lesion or its location deep in the body preclude its detection by palpation. In general, such a lesion may or may not possess echogenic properties that would make it ultrasonically detectable. Elastography is an ultrasonic method for imaging the elasticity of compliant tissues. The method estimates the local longitudinal strain of tissue elements by ultrasonically assessing the one dimensional local displacements. This information can be combined with first order theoretical estimates of the local stress to yield a quantitative measure of the local elastic properties of tissue. The elasticity information is displayed in the form of a gray scale image called an elastogram. An experimental system for elastography in phantoms based on a single element transducer has been described previously [1]. Here we introduce a new elastography system based on a linear array transducer that is suitable for in vivo scanning. We describe tissue mimicking phantom experiments and preliminary in vivo breast and muscle elastograms confirming the feasibility of performing elastography in vivo. An elastogram of a breast containing an 8 mm palpable cancer nodule clearly shows the lesion. Elastograms and their corresponding sonograms show some similarities and differences in the depiction of tissue structures.

Adult↗

PubMed1994

Late enlargement of radiofrequency lesions in infant lambs. Implications for ablation procedures in small children.

BACKGROUND: Despite the current clinical use of radiofrequency (RF) catheter ablation in infants, the acute and late effects of RF lesion production in immature myocardium remain unknown. This study was specifically designed to investigate the pathology of RF lesions in developing sheep myocardium. METHODS AND RESULTS: In study 1, RF lesions were made on the epicardial left ventricular surface of the beating heart in 15 sheep, 5 approximately 4 weeks of age (11.0 +/- 1.0 kg) and 10 approximately 8 weeks of age (23.8 +/- 3.4 kg), to assess the effects of RF application duration (10 to 90 seconds) and electrode tip temperature (45 degrees to 90 degrees C) on lesion size in immature myocardium. Lesion width and depth increased asymptotically with RF duration, to 7.0 +/- 0.7 and 4.8 +/- 1.0 mm at 90 seconds, respectively. The time to reach one-half lesion size was 6.5 seconds for width and 12.0 seconds for depth. Lesion width increased nearly linearly with tip temperature above 50 degrees C, but depth followed a sigmoid relation, with no increase above 80 degrees C. In study 2, RF lesions were made in all four cardiac chambers under fluoroscopic guidance in 19 infant sheep (10.9 +/- 1.4 kg). Lesion sizes and histological characteristics were assessed acutely (acute, n = 5), at 1.07 +/- 0.02 months (1 month, n = 5), and at 8.5 +/- 0.5 months (late, n = 9). Atrial and ventricular lesions but not atrioventricular groove lesions apparently increased in size during the follow-up period. Atrial lesions width increased from 5.3 +/- 0.5 to 8.7 +/- 0.7 mm at 1 month (164%) but did not increase further at late follow-up, while ventricular lesion width increased from 5.9 +/- 0.8 to 10.1 +/- 0.7 mm (171%) at late follow-up but was not significantly changed at 1 month. Histological evaluation revealed replacement of normal myocytes with fibrous and elastic tissue at 1 month and late follow-up in all locations but also demonstrated a poorly delineated border with multiple extensions of fibrous and elastic tissue into surrounding normal myocardium in late ventricular lesions. CONCLUSIONS: RF lesion formation in immature sheep myocardium is similar to that in adult myocardium acutely but is associated with late lesion enlargement and fibrous tissue invasion of normal myocardium. These findings may have implications for clinical RF ablation procedures in infants.

Animals↗

PubMed1989

Microprobe analysis of element distribution in bovine extracellular matrices and muscle.

The concentrations of some essential elements, Na, K, P, S and Cl were determined by microprobe analysis in bovine extracellular matrices of cartilage, tendon and elastic tissue (ligamentum nuchae) and in muscle cells. The values for the different tissues were compared and related to the blood electrolyte concentrations. Among the connective tissues the highest Na and lowest Cl values were found for cartilage which bears a high negative charge. The lowest concentrations of these elements occurred in elastic tissue which is relatively non-polar. In the three extracellular matrices sodium levels exceeded potassium. In myofibers potassium was the major cation at 30 times the blood value and about 3 times the concentration of sodium. Chlorine values were around 0.4 that of blood. Sulfur and phosphorus are components of the tissue macromolecules. The negative charge on the extracellular matrices is a function of carboxyl and sulfate radicals. In the myofiber this property is largely attributable to carboxyl and phosphate groups. Differences in potassium-sodium distribution in cells and extracellular matrices are attributed partly to the microtrabecular lattice and to the ordered state of cell water. In general the element concentrations and selective distribution can be related to the chemical composition and organization of the tissue, the net immobile charge, the nature of the dispersion medium (water) and changes in its dielectric constant, and to the physico-chemical properties of the individual ions.

Animals↗

PubMed1983

The dimensional characteristics of smooth muscle in rat blood vessels. A computer-assisted analysis.

This investigation was undertaken to provide precise information about the dimensional characteristics of vascular smooth muscle cells as related to their paracellular matrix. The representative types of vessels were fixed at the mean blood pressures of adult male Wistar rats. The shapes, positions of the nucleus, linear dimensions, volumes, and orientation within the vessel wall were determined by a computer-assisted reconstruction of the cells from serial sections. Wall-to-lumen and cellular-to-paracellular ratios also were assessed. The smooth muscle cells were elongate, but whereas some are spindle shaped, most are not, and may be shaped like flattened triangles, paddles, boomerangs, or hourglasses, and in addition, any one of these shapes may be forked. The nucleus tended to be in the largest part of the cell, wherever that region occurred. Thus, the majority of the nuclei (61%) were not centrally located, but overlapped the middle and end thirds of the elongate cells. Of the three arteries investigated, the muscular type tail artery had cells with volumes two to three times larger (P less than 0.01) than cells in a musculoelastic (femoral) or elastic (mesenteric) artery, and six times larger (P less than 0.01) than those of the portal vein. Therefore, the smooth muscle cells of the vein were significantly smaller than those in any artery (P less than 0.01). The smooth muscle cells were aligned at a steeper angle in the vessel wall (15 degrees +/- 2 degrees) of the muscular artery than in those with more elastic tissue (9 degrees +/- 2 degrees), with a higher percentage of circumferential cells in the latter. The wall-to-lumen ratios decreased as the relative amount of paracellular matrix, particularly elastic tissue, increased in the three arteries. Therefore, irregularly shaped cells, with the nucleus in the thickest region, and having characteristic cell volumes depending on the type of vessel, form the vascular smooth muscle tissue. These factors are relevant if stereology, or measuring from two dimensions, is used to estimate size characteristics in cardiovascular disease such as hypertension. In addition, the optimum angle at which vascular strips are cut would vary, for example, when used in testing pharmacological agents.

Animals↗

PubMed1988

Aneurysm of the rabbit common carotid artery induced by periarterial application of calcium chloride in vivo.

Experimental aneurysmatic dilatation of the rabbit common carotid artery was induced by a single, periarterial application of calcium chloride in vivo. Vessels were fixed in situ after 3 d, 1 wk, 3 wk, 6 wk, and 12 wk by intracardiac perfusion of glutaraldehyde and tissues prepared for light, scanning, and transmission electron microscopy. Progressive focal aneurysmal dilatation was seen limited to the site of calcium application with endothelial damage and thrombus formation in areas of irregular luminal contour. Disruption of the elastic network of the intima and media was seen with varying degrees of intimal fibromuscular hyperplasia and medial disorganization. The calcium-elastic tissue complex was the focus of the inflammatory, arteriosclerotic reaction and subsequent aneurysm formation. The inflammatory cell infiltration initially included primarily neutrophils followed by lymphocytes, plasma cells, monocytes, and multinucleated giant cells. These studies support the hypothesis that disruption of the elastic tissue network of the vascular wall represents an important pathogenetic factor in the initiation of aneurysmal dilatation. In addition, the results of these studies suggest that interaction of calcium with the elastica of the arterial wall may represent an important pathogenetic factor in the initiation of giant cell arteritis.

Aneurysm↗

PubMed1999

Aortic medial changes associated with bicuspid aortic valve: myth or reality?

OBJECTIVE: To determine whether aortic medial changes are more severe in patients who require aortic valve replacement of congenitally bicuspid aortic valves (BAV) than in patients who require replacement of tricuspid aortic valves and acquired valvular disease (AVD). DESIGN: Aortas from autopsies of 14 patients with BAV and 25 with AVD were histologically assessed by two 'blinded' cardiovascular pathologists and analyzed independently with computer-aided morphometry. The aortic valves were examined for valvular fibrosis and calcification. SETTING: The patient population was from a tertiary-care facility. PATIENTS: Patients were selected by retrospective review of autopsy records for patient deaths after aortic valve replacement, over the period 1984 to 1995. RESULTS: There were no significant differences in age (P=0.89), sex (P=0.94), prevalence of systemic arterial hypertension (P=0.37), valvular degenerative changes (P=0.10 and P=1.0) or heart weights (P=0.60) between the two groups. Histological scores for aortic medial degenerative changes including elastic fragmentation, fibrosis and medionecrosis were not statistically different between the groups. However, morphometry demonstrated less elastic tissue in patients with BAV (P=0.003). CONCLUSION: Routine microscopy shows no significant difference in the degree of aortic medial degenerative changes between patients with BAV and AVD. However, morphometry shows less elastic tissue in the aortas of BAV patients. This may explain the anecdotal increase in aortic fragility and propensity for aortic dissection in these patients.

Aged↗

PubMed1993

Idiopathic middermal elastolysis.

A 42-year-old white woman experienced widespread fine wrinkling and perifollicular protrusions in areas of erythematous patches with obvious photodistribution. Histological examination of the affected skin revealed loss of elastic tissue limited to the middermis. The clinical and histological presentation meets the criteria for the diagnosis of idiopathic middermal elastolysis. These findings support the previously postulated inflammatory pathogenesis for the loss of middermal elastic tissue and suggest that sun exposure may be a contributing factor. Idiopathic middermal elastolysis may represent only a variant in a spectrum of acquired wrinkling due to elastolysis with varying histological and clinical findings.

Adult↗