Stereological analysis of elastic fibers of the corpus cavernosum of rats during the aging process

Abstract Purpose To evaluate changes in the quantity of elastic fibers in the corpora cavernosa of rats during the natural aging process, and to assess the degree of this change by determining volumetric density (Vv) at different ages via stereological analysis. Methods Forty-eight rats, raised under similar conditions, were subjected to the natural aging process and divided into four groups (G1 to G4), according to age at the time of penectomy (6, 9, 12, and 24 months, respectively). Histological sections of the middle segment of the penis were stained with Weigert's resorcin-fuchsin, and the volumetric density (Vv) of elastic fibers of the corpora cavernosa were determined via stereological analysis. Results There were no statistically significant differences in Vv among groups G1, G2, and G3. These three groups were therefore considered as a single group. The mean Vv of this group showed a statistically significant reduction compared to that of G4 (0.16 vs. 0.11, p<0.05). Conclusion Natural aging in rats was responsible for a reduction in volumetric density of elastic fibers of the corpora cavernosa (approximately 30% decrease in Vv) during senescence.

Ultrastructural aspects of pseudoxanthoma elasticum

Abstract: We report the ultrastructural findings in a case of a 72-year-old black woman with confluent yellowish papules in the cervical region. She had no comorbidities. Ophthalmological examination, electrocardiogram, and echocardiogram were normal. Hematoxylin-eosin staining of the affected skin showed strong alterations in the mid-dermis with irregular clumps of eosinophilic material and loss of the normal parallel arrangement of collagen bundles. Orcein staining revealed that the elastic fibers lost their normal linear configuration, showing clump fragmentation, sometimes forming square structures. Transmission electron microscopy showed aberrant elastic fibers with an irregular outline and heterogenic inner structures. We also observed small elastic fibers. Collagen fibers showed a normal structure with irregular distribution. Scanning electron microscopy revealed important disorganization of collagen fibers and small stone-like deposits measuring around 5 µm associated with bigger structures ranging from 10-16 µm. Higher magnification revealed that these small stone-like structures were sometimes polyhedral-shaped or squared.

Comparative histological study of human adult cervical and lumbar intervertebral discs and its relation to functions and diseases

The intervertebral discs are the major structural links between adjacent vertebrae. They serve to allow greater movement and compression between vertebral bodies. However, there is regional difference in disc structure and pathology relative to different mechanical stresses and load bearing. Comparing the histological structure of human cervical and lumbar intervertebral discs at adult age to analyze the extent of variations in structure between these regions and its relation to their functions and diseases. [12] IVDs: [4] C3C4, [4] L4L5 and [4] L5S1 and adjacent bony vertebrae were removed from each of 12 adult male and female humans at autopsy. The discs and vertebrae were processed for paraffin sections and stained by haematoxylin and eosin, trichrome, orcein and safranin stains. Histomorphometric study and statistical analysis were conducted. L4-L5, L5-S1 IVDs presented less collagen and more elastic fibers in posterior region of annulus fibrosus than anterior region, peripheral regions were thicker than central one of lumbar end plate. The annulus fibrosus invading nucleus pulposus and dividing it but at cervical level invading without dividing it. Safranin reaction was positive and much higher in cervical than in lumbar annulus fibrosus. The reaction was much higher in lumbar than in cervical nucleus pulposus. There are significant differences in collagen, elastic fibers and heights of cervical and lumbar discs. There are histological differences of human adult intervertebral discs in cervical and lumber regions which may affect their mechanical and physiologic functions and provide a better understanding of the external factors causing spinal disorders and enable the best method to be applied to the patients both at the diagnosis and the treatment stage

Structural changes of dilated pelvic ureters in adults

PURPOSE: To perform a quantitative assessment of different types of pelvic ureter tissues with chronic dilation in adults, using stereological methods. METHODS: We analyzed fragments of dilated pelvic ureters obtained from 6 patients aged between 35 and 67 years (mean, 46 years) who underwent ureteral reimplantation surgery for different reasons. The obstruction duration ranged from 27 to 180 days (mean, 93 days). The control group included fragments of normal pelvic ureters obtained during nephrectomy in 7 kidney transplant donors (age: range, 25-51 years; mean, 36 years). The volumetric density of collagen in the ureter, elastic fibers, and smooth muscle fibers was assessed. RESULTS: The volumetric density (Vv) of collagen showed no significant difference between the two groups (control: 45.3 ± 6.1; dilated: 40.8 ± 6.9; P = 0.23). A statistically significant increase in Vv of elastic fibers was observed in the dilated ureters (control: 18.4 ± 1.2; dilated: 24.6 ± 5.4; P = 0.03). A statistically significant increase in the Vv of smooth muscle fibers was observed in the dilated ureter (control: 42.0 ± 6.0; dilated: 56.2 ± 6.1; P = 0.001). CONCLUSION: The chronically dilated pelvic ureters had significantly more elastin and smooth muscle contents than the controls. .

Age-related changes in the concentration of elastic fibers in different regions of the rabbit penis

PURPOSE: To investigate whether elastic fiber content in the corpus cavernosum (CC), corpus spongiosum (CS) and tunica albuginea (TA) of the rabbit penis undergoes modifications with age. METHODS: Rabbits were sacrificed, in groups of ten animals each, at 30, 120, 240, and 730 days of age. Histological sections were obtained from the penile middle shaft and were stained with Weigert's resorsin fuchsin. The content of elastic fibers was determined using stereological methods, and was expressed as volume fraction. RESULTS: At 730 days of age, elastic fiber content was increased by 54% (p<0.004), 78% (p<0.004), and 87% (p<0.004) in the TA, CC, and CS, respectively, compared with animals aged 30 days. After 30 days of age, the concentration gradually and significantly increased until 240 days of age. In 730-day old animals, the concentration, compared with the previous age group, was unchanged in the CC and decreased by 20% (p<0.004) in the TA. CONCLUSIONS: Elastic fiber contents in the rabbit penis correlate with properties of penile tissues. Although after one month of age there is a gradual increase in these concentrations, in two-year old animals this trend is interrupted, which suggests that this could be an early alteration due to senescence.

Morphological and ultrastructural characteristics of extracellular matrix changes in oral squamous cell carcinoma.

Background: The biology of oral squamous cell carcinoma (OSCC), including its progression from dysplasia to carcinoma, "field effects", genetic changes in tumor associated mucosa (TAM) and effect of matrix metalloproteinases in breaking down of matrix proteins to facilitate invasion, has been well documented. However, what remains to be done is to extrapolate this knowledge to improve patient care. Aim: The aim of this study was to observe the extracellular matrix (ECM) changes with the routine histochemical stains available to most histopathologists. Materials and Methods: The study includes 72 cases of OSCC in which the tumor and adjacent normal appearing areas were sampled to study the ECM changes with hematoxylin and eosin (H and E) and Verhoeff's-Van Gieson elastic stain (VVG). Results: Basophilic fragmentation of collagen (H and E) and clumped short elastic fibers (VVG) were seen in 12 (16.7%) cases. Of the remaining cases, 18 (25%) had a dense lymphocytic infiltrate and had no demonstrable elastic fibers. Those cases with H and E changes were further studied and compared with normal mucosa for ultrastructural changes. The ultrastructural study demonstrated an increase in oxytalan, elaunin and elastic fibers and decrease in collagen fibers with some transformation changes associated with OSCCs and lymph node metastasis. Conclusion: Changes in transformation of collagen to elastic fibers and also the loss of both the fibers in areas of lymphocytic infiltration possibly indicate degradation of ECM fibers by factors released from the lymphocytes or tumor cells and the limiting effect on the tumor by ECM remodeling.

Analise da arquitetura da aorta de pacientes hipertensos e normotensos / Texture analysis of the elastic fibers in aortas of normotensive and hypertensive patients

Fibras elásticas são componentes essenciais da aorta e remodelamento é acompanhado em muitas doenças e eventos que ameaçam a vida, como dissecção e rupturas. Fibras elásticas podem ser facilmente visualizadas quando coradas com H&E e examinadas por microscopia de fluorescência. Nosso objetivo foi criar um sistema de análise automática da textura das fibras elásticas comparando aorta de pacientes normotensos e hipertensos. O sistema de análise foi composto por Microscópio invertido Olympus IX-81 equipado com scanner FV 300 que utiliza laser FV-5 COMB2, utilizando laser de argônio a 488 nm, objetiva 40x usando óleo de imersão. A espessura da aorta varia de 2 a 3 mm, e a imagem completa foi composta por justaposição de imagens de 220x220 µm utilizando software Fluoview. Para análise foi utilizado o programa gliding box , que é uma caixa deslizadora de 128x128 pixels, que percorre a imagem da aorta pixel a pixel em toda sua extensão. Para análise computadorizada da textura foram utilizados programas computacionais (entropia, homogeneidade local e segundo momento angular derivado da matriz de co-ocorrência de Haralick). Foram calculados e plotados em diagramas resultados equivalentes à topografia histológica da imagem. Em cada caminho o gliding box percorreu entre 2000 e 3000 pixels da textura, revelando a topografia local e sua variação. Foi comparada a textura de fibras elásticas de cortes histológicos corados com HE de 24 pacientes normotensos e 30 hipertensos, adultos de ambos os sexos oriundos de autópsias realizadas no Depto de Anatomia Patológica. Para comparação entre textura e idade utilizou-se Correlação de Pearson, e a textura foi comparada entre os grupos com o auxílio do teste t. Resultados: Tanto nos pacientes normotensos como nos hipertensos não houve correlação entre: número de fibras elásticas ou distâncias entre elas, para as análises de Haralick e idade dos pacientes. No entanto, a entropia em...

The elastic fiber network is an essential component of the aorta. Its remodeling accompanies many diseases and may provoke life-threatening events, such as dissection or rupture. Elastic fibers can be easily demonstrated in eosin-stained histologic sections examined by fluorescence microscopy. The aim of our study was to create an automatic texture analysis system of the elastic fibers and to apply it in human aortas comparing normotensive and hypertensive patients. The analysis sytem was composed of an Olympus IX-81 inverted microscope, a FV300 scan head and a FV-5 COMB2 laser combiner. The fluorescence of the hematoxylin and eosin-stained slides was excited with the 488 nm line of an Argon laser using a 40x oil immersion objective. The Fluoview software was used to reconstruct the images. The full image of the whole sample (2 or 3mm long) was composed by several 220x220. Then a gliding box of 128x128 pixels was running in 1-pixel steps along a predefined axis parallel to the bottom line of the image. For every new box, computerized analysis of texture features (entropy, local homogeneity and the second angular moment derived from the gray-level co-occurrence matrix) were calculated and plotted in diagrams, where the position on the x-axis was equivalent to the topography in the histologic picture. In that way for each "run" of the gliding box about 2000 to 3000 values of a texture feature were obtained, thus revealing precisely its topographic postion and its variabilty. We compared the elastic fiber texture in routinely HE-stained histologic slides of the aorta ascendens in 24 normotensive and 30 hypertensive adult patients of both sexes and of similar age from our autopsy files. Pearson correlations were calculated between the texture...

Structure of the aortic wall in the guinea pig and rat

The segmental microscopic architecture of the aortic wall of guinea pigs and albino rats was studied at the thoracicascending (T2-3), thoracic descending (T6-7) and abdominal infrarenal (L5-6) levels. Variables such as layer thickness,the number of elastic lamellae in the medial layer, and the diameter of the aortic segments were analyzedhistomorphometrically. The aortic wall of both species showed the usual elastic pattern, although variable amounts ofelastic lamellae, collagen fibers and smooth muscle cells were observed in the segmental analyses. A marked reductionin the number of elastic lamellae in the medial layer and in vascular diameter was observed in the abdominal aorticsegment of both species. Intimal folds, a gradual decrease in elastic lamellae from the ascending to the aorta abdominalaorta and a meshwork of adventitial collagen fibers and elastic lamellae were observed. These data indicate that thereare small but significant segmental variations in the aortic wall of these two species.

Structural characterization and distribution of elastic system fibers in the human prostate and some prostatic lesions

Prostatic disorders are accompanied by extensive but poorly understood modifications of the cells and surrounding extracellular matrix. In this study, we examined the distribution of the elastic system fibers in prostatic disorders compared to normal tissue. Sections of prostatic transurethral resections and/or radical prostatectomies were examined after staining with hematoxylin-eosin plus fluorescence microscopy and after Weigert's staining for elastic fibers. Transmission electron microscopy was used to examine the ultrastructure of tissues from radical prostatectomy. A concentric fibrous extracellular matrix and smooth muscle cells were observed surrounding normal acini. The elastic fibers were thin and inconspicuous. In benign prostatic hyperplasia (BPH) the elastic components were of variable thickness and formed a three-dimensional network at the base of the epithelium. Conversely, increased variability in the elastic fiber distribution was observed in adenocarcinomas, depending on the tumor grade. In adenocarcinomas with little differentiation, in some hyperplasic acini, and in the stroma adjacent to tumoral mass, ruptured and residual elastic fibers indicative of matrix degradation or remodeling were seen. In more undifferentiated tumors, a pre-elastic network, perhaps indicative of a new extracellular matrix microenvironment was seen. These results indicate that prostate cancer cell invasion involves extensive remodeling of the fibers of the elastic system.

Estudo histoquímico de fibras oxitalânicas no ligamento periodontal de ratos normais e submetidos a forças mecânicas excessivas / Histochemical study of oxytalan fibers in the normal and repaired periodontal ligament of rats submitted to an excessive mechanical force

Os incisivos inferiores de sete ratos foram comprimidos um contra o outro por 7 dias para detectar a fibra oxitalânica na reparaçäo do ligamento periodontal. Retirados os aparelhos, três animais foram sacrificados imediatamente e os outros em 7, 14, 28 e 52 dias. Foi demonstrado, por histoquímica, que a força mecânica empregada promoveu a degeneraçäo do ligamento periodontal. As fibras oxitalânicas apresentavam-se aumentadas no período de reparaçäo, principalmente após 28 dias. Portanto, essas fibras podem ter um importante papel no suporte do ligamento periodontal normal em em reparaçäo

A comparative study of aging of the elastic fiber system of the diaphragm and the rectus abdominis muscles in rats

In the present study the age-related changes of the striated muscle elastic fiber system were investigated in the diaphragm and rectus abdominis muscles of 1-, 4-, 8- and 18-month-old rats. The activation patterns of these muscles differ in that the diaphragm is regularly mobilized tens of times every minute during the entire life of the animal whereas the rectus abdominis, although mobilized in respiration, is much less and more irregularly activated. The elastic fibers were stained by the Verhoeff technique for mature elastic fibers. Weigert stain was used to stain mature and elaunin elastic fibers, and Weigert-oxone to stain mature, elaunin and oxytalan elastic fibers. The density of mature and elaunin elastic fibers showed a progressive increase with age, whereas the amount of oxytalan elastic fibers decreased in both diaphragm and rectus abdominis muscles and their muscular fascias. These age-related quantitative and structural changes of the elastic fiber system may reduce the viscoelastic properties of the diaphragm and rectus abdominis muscles, which may compromise the transmission of tensile muscle strength to the tendons and may affect maximum total strength

Ultrastructural changes of the external elastic lamina in experimental hypercholesterolemic porcine coronary arteries

The external elastic lamina (EEL) serves as a barrier for cells and macromolecules between the media and adventitia in the vascular wall. We evaluated the morphological changes and quantitative assessments of the EEL architecture in the coronary circulation of pigs fed with a high cholesterol diet. Confocal microscopy analysis of the EEL from hypercholesterolemic coronary arteries revealed an altered pattern characterized by fragmentation and disorganization of the EEL associated with an increase in the thickness. Computerized digital analysis of the images obtained by confocal scanning microscopy demonstrated that compared to normal coronary arteries, the EEL of hypercholesterolemic coronary arteries decreased in the percentage of their elastin content (30.80 +/- 1.64% vs. 47.85 +/- 1.82%, p = 0.001). The percentage of elastin content was negatively correlated with the vessel wall area (r = -0.82, p = 0.001). The immunoreactivity for matrix metalloproteinase-3 (MMP-3) increased in cholesterol-fed coronary arteries, predominantly in the neointima and adventitia. This study demonstrates that experimental hypercholesterolemia induced ultrastructural changes of the EEL in coronary circulation. The EEL may also be an atherosclerosis-prone area compared with the intima. The EEL may play an important role in the development of structural changes which characterizes the early phase of coronary atherosclerosis and vascular remodeling.

Experimental hypercholesterolemia induces ultrastructural changes in the elastic laminae of rabbit aortic valve

Atherosclerosis is the most severe problem in the high-pressure systemic circulation and similar changes also occur in the high-pressure loading valve. This study was designed to test the hypothesis that early atherosclerosis, induced by a high cholesterol diet in rabbits, is characterized by significant ultrastructural change in the elastic laminae of the aortic valve. However, it is not known whether this process is also taking place in the cardiac valve at the early stage of atherosclerosis. Animals were fed either a high cholesterol diet (n = 5) or a control diet (n = 5) for 10-12 weeks. Histologic analysis demonstrated that subendothelial thickening and foam-cell infiltration were evident in the arterialis of aortic valves. Confocal microscopy revealed an altered pattern characterized by fragmentation and disorganization of the arterialis elastic laminae of hypercholesterolemic valves. Computerized digital analysis of the images obtained by confocal scanning microscopy demonstrated that compared to normal valves, the arterialis elastic laminae of hypercholesterolemic valves decreased in percentage of their elastin content (29.03 +/- 1.10% vs. 42.94 +/- 1.35%, p = 0.023). Immunohistochemical staining for matrix metalloproteinase-3 (MMP-3) revealed MMP-3 immunoreactivity was increased in hypercholesterolemic valves, predominantly in the arterialis. This study demonstrated that early atherosclerosis, induced by a high cholesterol diet in rabbits, is characterized by significant ultrastructural change in the elastic laminae of the aortic valve. The arterialis endothelium of the aortic valve may be a more atherosclerosis-prone area compared with the ventricularis. The presence of ultrastructural defect in the elastic laminae may play a role in chronic degenerative change and a resultant valvular dysfunction.

Las fibras elásticas y el pulmón / The elastic fibers and the lung

La matriz extracelular (ME) del tejido conectivo pulmonar se diferencia en membranas basales y matriz intersticial. Esta última se constituye por un armazón de proteínas colagénicas fibrosas y de fibras elásticas amorfas, que están embebidas dentro de una sustancia basal viscoelástica compuesta por proteoglicanos y glicoproteínas. La ME le proporciona al pulmón sus propiedad mecánicas. Las colágenas proveen tensión, mientras que las fibras elásticas permiten el desarrollo de la expansión elástica, con la subsecuente recuperación característica de este órgano. Las fibras elásticas se constituyen por fibras amorfas de elastina polimérica combinada con ciertas glicoproteínas conocidas como microfibrillas, con proporciones variables según su estadio ontogénico. Este material amorfo constituye toda una malla que comprende un armazón continuo, por todo el pulmón, y en conexión estrecha con las fibras de colágena permite la actividad mecánica del pulmón. La elastina es una molécula altamente hidrofóbica, con una relación intron: exón de 15:1, sintetizada junto con un receptor que guía su polimerización en sitios determinados por las microfibrillas previamente depositadas

Estudo das fibras do sistema elástico no carcinoma basocelular nódulo-ulcerativo da pele humana exposta ao sol / Contribution to study of elastic system fibers in the noduloulcerative basal cell carcinoma of sun exposed skin

Fundamento - As fibras do sistema elástico da derme humana normal já foram amplamente estudadas; entretanto, carecem de estudos em patologia tumoral cutânea. Objetivos - Identificaçäo e distribuiçäo das fibras do sistema elástico, ao microscópio óptico, no carcinoma basocelular nódulo ulcerativo da pele humana exposta ao Sol. Método - Foram estudados vinte doentes com carcinoma basocelular nódulo-ulcerativo. As peças cirúrgicas foram histologicamente processadas e coradas pela hematoxilina e eosina (HE) e, seletivamente, para as fibras do sistema elástico. Resultados - Mediante técnicas de coloraçäo seletivas, o estudo revelou completa desestruturaçäo, fragmentaçäo e ausência do padräo normal das fibras do sistema elástico nos locais onde se desenvolve um carcinoma basocelular nódulo-ulcerativo, bem como presença de grande número de mastócitos entre as massas e lóbulos tumorais. Conclusöes - Observam-se, nos locais onde se desenvolve um carcinoma basocelular nódulo-ulcerativo da pele humana exposta ao Sol: 1. virtual ausência das fibras oxitalânicas, elaunínicas e eláticas na regiäo adjacente à junçäo demoepidérmica; 2. completa alteraçäo do modelo normal de distribuiçäo das fibras do sistema elático da pele fina; e 3. grande número de mastócitos, delineando as massas e lóbulos tumorais

Estudo micro-mesoscópico das granulaçöes aracnóides humanas / A micromesoscopic study of human arachnoid granulations

A anatomia funcional das granulaçöes aracnóides do seio sagital superior foi estudada por técnicas micro-mesoscópicas a fim de contribuir para esclarecimentos de vias de drenagem do líquido cerebrospinal através de seus componentes fibrosos. A disposiçäo dos elementos fibrosos foi analisada na base do pedículo, pedículo, centro e ápice da granulaçäo. A análise dos cortes seriados mostra na base do pedículo, centro e ápice da granulaçäo. A análise dos cortes seriados mostra na base do pedículo, malhas de colágeno com morfologia predominantemente circular orientando-se longitudinalmente no sentido do maior eixo do pedículo. Estes feixes emergem no centro da granulaçäo, ramificando-se a seguir em direçäo ao ápice e à periferia da granulaçäo. Os feixes elásticos possuem disposiçäo semelhante à descrita para feixes colágenos e delimitam, com estes, canais intercomunicantes desde a base do pedículo ao ápice da granulaçäo. Encontramos, na base do pedículo, feixes de fibras reticulares dispostos entre as malhas de colágeno. A cápsula fibrosa da granulaçäo encontra-se constituída de feixes colágenos e de pequena quantidade de fibras elásticas

Fibras elásticas, elaunínicas e oxitalánicas no plexo mientérico do esôfago humano / Elastic fibers, eleaunic and oxitalanic of the human esophagus myenteric plexus

The elastic system in the myenteric plexus of the human esophagus was studied by light and electron microscopy. Elastic, elaunin and oxytalan fibers were identified by their staining characteristic a fine structural morphology. The bulk of the ganglionic sheet consists of coarse eladtic fibers and elaunin fibers. Elaunin fibers and oxytalan fibers form the intraganglionic network. The oxytalan, elaunin and elastic fibers appear to be located in area related to different stresses and deformation to which the ganglia if the myenteric plexus are exposed during the motor activity of the esophageal wall