Altered Elastic Fibers Research Articles

Elastic fiber alterations and calcifications in calcific uremic arteriolopathy

Calcific uremic arteriolopathy (CUA) is a severely morbid disease, affecting mostly dialyzed end-stage renal disease (ESRD) patients, associated with calcium deposits in the skin. Calcifications have been identified in ESRD patients without CUA, indicating that their presence is not specific to the disease. The objective of this retrospective multicenter study was to compare elastic fiber structure and skin calcifications in ESRD patients with CUA to those without CUA using innovative structural techniques. Fourteen ESRD patients with CUA were compared to 12 ESRD patients without CUA. Analyses of elastic fiber structure and skin calcifications using multiphoton microscopy followed by machine-learning analysis and field-emission scanning electron microscopy coupled with energy dispersive X-ray were performed. Elastic fibers specifically appeared fragmented in CUA. Quantitative analyses of multiphoton images showed that they were significantly straighter in ESRD patients with CUA than without CUA. Interstitial and vascular calcifications were observed in both groups of ESRD patients, but vascular calcifications specifically appeared massive and circumferential in CUA. Unlike interstitial calcifications, massive circumferential vascular calcifications and elastic fibers straightening appeared specific to CUA. The origins of such specific elastic fiber’s alteration are still to be explored and may involve relationships with ischemic vascular or inflammatory processes.

Histopathology of resected tissue from repair of anomalous aortic origin of a coronary artery: Potential mechanism of coronary artery compression

ObjectiveThis study aimed to describe the histomorphologic characteristics of resected (unroofed) common wall tissue from repair of anomalous aortic origin of a coronary artery and to determine whether the histologic features correlate with clinical and imaging findings. MethodsThe histology of resected tissue was analyzed and reviewed for the presence of fibrointimal hyperplasia, smooth muscle disarray, mucoid extracellular matrix accumulation, mural fibrosis, and elastic fiber disorganization and fragmentation using hematoxylin and eosin and special stains. Clinical, computed tomography imaging, and surgical data were correlated with the histopathologic findings. ResultsTwenty specimens from 20 patients (age range, 7-18 years; 14 males) were analyzed. Anomalous aortic origin of a coronary artery involved the right coronary in 16 (80%), and a slit-like ostium was noted in 18 (90%). By computed tomography imaging, the median proximal coronary artery eccentricity index was 0.4 (range, 0.20-0.90). The median length of intramural course was 8.2 mm (range, 2.6-15.2 mm). The anomalous vessel was determined to be interarterial in 14 patients (93%, 15 had evaluable images). The median distance from a commissure was 2.5 mm above the sinotubular junction (STJ) (range: 2 mm below the STJ–14 mm above the STJ). Prominent histopathologic findings included elastic fiber alterations, mural fibrosis, and smooth muscle disarray. The shared wall of the aorta and intramural coronary artery is more similar to the aorta histologically. Mural fibrosis and elastic fiber abnormalities tended to be more severe in patients >10 years of age at the time of surgery, but this did not reach statistical significance. The extent of vascular changes did not appear to have a clear relationship with the imaging features. ConclusionsThe findings confirm the aortic wall–like quality of the intramural segment of the coronary artery and the presence of pathologic alterations in the wall microstructure.

Physiological Impact of a Synthetic Elastic Protein in Arterial Diseases Related to Alterations of Elastic Fibers: Effect on the Aorta of Elastin-Haploinsufficient Male and Female Mice.

Elastic fibers, made of elastin (90%) and fibrillin-rich microfibrils (10%), are the key extracellular components, which endow the arteries with elasticity. The alteration of elastic fibers leads to cardiovascular dysfunctions, as observed in elastin haploinsufficiency in mice (Eln+/-) or humans (supravalvular aortic stenosis or Williams-Beuren syndrome). In Eln+/+ and Eln+/- mice, we evaluated (arteriography, histology, qPCR, Western blots and cell cultures) the beneficial impact of treatment with a synthetic elastic protein (SEP), mimicking several domains of tropoelastin, the precursor of elastin, including hydrophobic elasticity-related domains and binding sites for elastin receptors. In the aorta or cultured aortic smooth muscle cells from these animals, SEP treatment induced a synthesis of elastin and fibrillin-1, a thickening of the aortic elastic lamellae, a decrease in wall stiffness and/or a strong trend toward a reduction in the elastic lamella disruptions in Eln+/- mice. SEP also modified collagen conformation and transcript expressions, enhanced the aorta constrictive response to phenylephrine in several animal groups, and, in female Eln+/- mice, it restored the normal vasodilatory response to acetylcholine. SEP should now be considered as a biomimetic molecule with an interesting potential for future treatments of elastin-deficient patients with altered arterial structure/function.

Inhibition of Vascular Endothelial Cadherin Cleavage Prevents Elastic Fiber Alterations and Atherosclerosis Induced by Intermittent Hypoxia in the Mouse Aorta.

Intermittent hypoxia (IH), the major feature of obstructive sleep apnea syndrome (OSAS), induces atherosclerosis and elastic fiber alterations. VE-cadherin cleavage is increased in OSAS patients and in an IH-cellular model. It is mediated by HIF-1 and Src-tyr-kinases pathways and results in endothelial hyperpermeability. Our aim was to determine whether blocking VE-cadherin cleavage in vivo could be an efficient strategy to inhibit deleterious IH-induced vascular remodeling, elastic fiber defects and atherogenesis. VE-cadherin regulation, aortic remodeling and atherosclerosis were studied in IH-exposed C57Bl/6J or ApoE-/-mice treated or not with Src-tyr-kinases inhibitors (Saracatinib/Pazopanib) or a HIF-1 inhibitor (Acriflavine). Human aortic endothelial cells were exposed to IH and treated with the same inhibitors. LDL and the monocytes transendothelium passage were measured. In vitro, IH increased transendothelium LDL and monocytes passage, and the tested inhibitors prevented these effects. In mice, IH decreased VE-cadherin expression and increased plasmatic sVE level, intima-media thickness, elastic fiber alterations and atherosclerosis, while the inhibitors prevented these in vivo effects. In vivo inhibition of HIF-1 and Src tyr kinase pathways were associated with the prevention of IH-induced elastic fiber/lamella degradation and atherogenesis, which suggests that VE-cadherin could be an important target to limit atherogenesis and progression of arterial stiffness in OSAS.

Early Alterations of Intra-Mural Elastic Lamellae Revealed by Synchrotron X-ray Micro-CT Exploration of Diabetic Aortas.

Diabetes is a major concern of our society as it affects one person out of 11 around the world. Elastic fiber alterations due to diabetes increase the stiffness of large arteries, but the structural effects of these alterations are poorly known. To address this issue, we used synchrotron X-ray microcomputed tomography with in-line phase contrast to image in three dimensions C57Bl6J (control) and db/db (diabetic) mice with a resolution of 650 nm/voxel and a field size of 1.3 mm3. Having previously shown in younger WT and db/db mouse cohorts that elastic lamellae contain an internal supporting lattice, here we show that in older db/db mice the elastic lamellae lose this scaffold. We coupled this label-free method with automated image analysis to demonstrate that the elastic lamellae from the arterial wall are structurally altered and become 11% smoother (286,665 measurements). This alteration suggests a link between the loss of the 3D lattice-like network and the waviness of the elastic lamellae. Therefore, waviness measurement appears to be a measurable elasticity indicator and the 3D lattice-like network appears to be at the origin of the existence of this waviness. Both could be suitable indicators of the overall elasticity of the aorta.

Evaluation of elastin fibres in young and aged eyelids and abdominal skin using computational 3D structural analysis.

BackgroundAging‐related degeneration of elastic fibres causes skin wrinkles and loss of elasticity. A correlation has been reported between dermal elastic fibre degradation and wrinkles. However, the mechanism of wrinkle formation is complex and unclear. To establish methods for treating wrinkles, it is necessary to understand the aging‐related morphological alterations underlying elastin fibre degradation or disappearance.ObjectivesTo image and analyse aging‐related three‐dimensional (3D) morphological alterations of elastic fibres in the eyelid and abdominal skin.MethodsExcised human eyelid and abdominal skin tissues were examined. The structure of elastic fibres in the skin tissues was examined via nuclear, tropoelastin and fibrillin‐1 immunostaining. Then, 3D imaging was performed using a confocal laser microscope and tissue decolourization technology. Images were analysed using a computational method.ResultsThe decolourization technology made it possible to image elastin fibres in 3D, and we devised a method for analyzing the elastin fibre structure using computational methods. It was quantitatively shown that the eyelid skin has a more complex fibrous structure than the abdomen, and the fibres became curved, shortened and thickened with age.ConclusionsWe provide a novel 3D analysis method for elastin fibres and report age‐related alterations in elastin fibre structure in the human eyelid and abdominal skin. This method contributes to the understanding of elastin fibre degeneration in more detail than conventional methods. Applying this 3D analysis method to skin tissues will contribute to a better understanding of age‐related changes in fibres and to the development of novel wrinkle treatments.

A Role for Clusterin in Exfoliation Syndrome and Exfoliation Glaucoma?

The multifunctional protein clusterin (CLU) is a secreted glycoprotein ubiquitously expressed throughout the body, including in the eye. Its primary function is to act as an extracellular molecular chaperone, preventing the precipitation and aggregation of misfolded extracellular proteins. Clusterin is commonly identified at fluid-tissue interfaces, and has been identified in most body fluids. It is a component of exfoliation material, and CLU mRNA is reduced in eyes with exfoliation syndrome compared with controls. SNPs located in the CLU genomic region have been associated with Alzheimer disease (AD) at the genome-wide level and several CLU SNPs located in an apparent regulatory region have been nominally associated with XFS/XFG in Caucasians with European ancestry and in south Indians. Interestingly, clusterin associates with altered elastic fibers in human photoaged skin and prevents UV-induced elastin aggregation in vitro. In light of the known geographic risk factors for XFS/XFG, which could include UV light, investigations of CLU-geographic interactions could be of interest. Future studies investigating rare CLU variation and other complex interactions including gene-gene interactions in XFS/XFG cases and controls may also be fruitful. Although CLU has been considered as a therapeutic target in AD, cancer and dry eye, a role for clusterin in XFS/XFG needs to be better defined before therapeutic approaches involving CLU can be entertained.

Novel Biologic Therapy for Untreated Diseases of Vascular Calcification

Diseases of medial wall vascular and connective tissue calcification associated with low plasma pyrophosphate (PPi) range from orphan diseases such as Pseudoxanthoma Elasticum (PXE) and Generalized Calcification of Infancy (GACI) to ubiquitous diseases of medial wall vascular calcification affecting every aging adult such as hardening of the arteries associated with aging. Although recognized as a potent mineralization inhibitor for over a generation, PPi has never been established as a causative agent in the broad class of connective tissue diseases and effective therapeutics capable of treating the calcifications driving the morbidity and mortality of these conditions is lacking. We have recently demonstrated that elevation of plasma PPi using a novel biologic containing the pyrophosphate generating enzyme ENPP1 is curative in rodent models of the rare orphan disease GACI - a severe lethal neonatal disease of arterial calcification. Here, we demonstrate the efficacy of this approach in a more common disorder of vascular and connective tissue calcification and low plasma PPi called PXE.PXE is a monogenic, hereditable connective tissue disease characterized by aberrant mineralization of the skin, eye, and vasculature. PXE is associated with loss of function mutations in the ABCC6 gene - a multi-pass ATP dependent membrane transport protein. Two opposing theories regarding the genetic etiology of PXE are held - a metabolic hypothesis postulating that ABCC6 mutations deprive the body of a global mineralization inhibitor, and a cellular hypothesis postulating that ABCC6 mutations compromise a stem cell progenitor locally present within specific tissues. Both etiologies are proposed to account for the regional mineral and elastic fiber alterations present in the disease.Although the substrate of ABCC6 is unknown, patients with PXE (and ABCC6 knockout mice) have plasma [PPi] at about 20-30% of unaffected (or wild-type) individuals. Furthermore, transfections of ABCC6 into HEK cells increase extracellular [ATP] in vitro. ATP is metabolized into PPi by the extracellular enzyme ENPP1, and the combined findings support the notion that ABCC6 mutations decrease extracellular [ATP] thereby limiting ENPP1 production of PPi by limiting the enzymatic substrate of the enzyme.Here, we demonstrate that subcutaneous administration of ENPP1-Fc, a fusion protein containing the enzyme ENPP1, normalizes serum PPi concentrations in ABCC6 knockout mice. Furthermore, we show that normalization of serum PPi by this means potently inhibits the regional connective tissue calcifications present in ABCC6 knockout mice. Our findings provide in vivo experimental evidence for the metabolic basis of PXE. Furthermore, because ENPP1 is downstream of ABCC6, the efficacy of ENPP1-Fc is surprising and indicates that reduced extracellular [ATP] may not be the etiology for the decreased plasma PPi concentrations reported in PXE patients as previously proposed. Finally, the efficacy of ENPP1-Fc on the connective tissue calcifications in PXE suggests that elevation of plasma PPi by this means may be efficacious in spectrum of severe and poorly treated connective tissue calcification disorders associated with low plasma PPi. DisclosuresBraddock:Yale University: Patents & Royalties: Yale University owns a patent on the technology, in which Demetrios Braddock is listed as an inventor.

Critical buckling pressure in mouse carotid arteries with altered elastic fibers

Arteries can buckle axially under applied critical buckling pressure due to a mechanical instability. Buckling can cause arterial tortuosity leading to flow irregularities and stroke. Genetic mutations in elastic fiber proteins are associated with arterial tortuosity in humans and mice, and may be the result of alterations in critical buckling pressure. Hence, the objective of this study is to investigate how genetic defects in elastic fibers affect buckling pressure. We use mouse models of human disease with reduced amounts of elastin (Eln+/−) and with defects in elastic fiber assembly due to the absence of fibulin-5 (Fbln5−/−). We find that Eln+/− arteries have reduced buckling pressure compared to their wild-type controls. Fbln5−/− arteries have similar buckling pressure to wild-type at low axial stretch, but increased buckling pressure at high stretch. We fit material parameters to mechanical test data for Eln+/−, Fbln5−/− and wild-type arteries using Fung and four-fiber strain energy functions. Fitted parameters are used to predict theoretical buckling pressure based on equilibrium of an inflated, buckled, thick-walled cylinder. In general, the theoretical predictions underestimate the buckling pressure at low axial stretch and overestimate the buckling pressure at high stretch. The theoretical predictions with both models replicate the increased buckling pressure at high stretch for Fbln5−/− arteries, but the four-fiber model predictions best match the experimental trends in buckling pressure changes with axial stretch. This study provides experimental and theoretical methods for further investigating the influence of genetic mutations in elastic fibers on buckling behavior and the development of arterial tortuosity.

Severe congenital cutis laxa with cardiovascular manifestations due to homozygous deletions in ALDH18A1

Autosomal recessive cutis laxa (ARCL) type 2 constitutes a heterogeneous group of diseases mainly characterized by lax and wrinkled skin, skeletal anomalies, and a variable degree of intellectual disability. ALDH18A1-related ARCL is the most severe form within this disease spectrum. Here we report on the clinical and molecular findings of two affected individuals from two unrelated families. The patients presented with typical features of de Barsy syndrome and an overall progeroid appearance. However, the phenotype was highly variable including cardiovascular involvement in the more severe case. Investigation of a skin biopsy of one patient revealed not only the typical alterations of elastic fibers, but also an altered structure of mitochondria in cutaneous fibroblasts. Using conventional sequencing and copy number analysis we identified a frameshift deletion of one nucleotide and a microdeletion affecting the ALDH18A1 gene, respectively, in a homozygous state in both patients. Expression analysis in dermal fibroblasts from the patient carrying the microdeletion showed an almost complete absence of the ALDH18A1 mRNA resulting in an absence of the ALDH18A1 protein. So far, only 13 affected individuals from seven unrelated families suffering from ALDH18A1-related cutis laxa have been described in literature. Our findings provide new insights into the clinical spectrum and show that beside point mutations microdeletions are a possible cause of ALDH18A1-ARCL.

Tight skin 2 mice exhibit a novel time line of events leading to increased extracellular matrix deposition and dermal fibrosis

The tight skin 2 (Tsk2) mouse model of systemic sclerosis (SSc) has many features of the human disease including tight skin, fibrosis, extracellular matrix abnormalities, and reported antinuclear antibodies (ANA). Here we report that Tsk2/+ mice develop excess dermal fibrosis with age, as skin is not significantly fibrotic until 10weeks, a full eight weeks after the development of the physical tight skin phenotype. Concomitantly with the tight skin phenotype at two weeks of age, Tsk2/+ mice demonstrate increased levels of total transforming growth factor beta 1 (TGF-β1) and excessive accumulation of dermal elastic fibers. The increase in elastic fibers is not responsible for tight skin, however, because Tsk2/+ mice genetically engineered to lack skin elastic fibers nevertheless have tight skin and fibrosis. Finally, about two months after the first measurable increases of total collagen, a portion of Tsk2/+ mice produce ANAs, but at a similar level to wild-type littermates. The timeline of disease development in the Tsk2/+ mouse shows that fibrosis is progressive, with elastic fiber alterations and TGF-β1 over-production occurring at least two months before bona fide fibrosis, that is not dependent on ANA production.

Elastosis Perforans Serpiginosa

Elastosis perforans serpiginosa is a rare skin disease characterized by transepidermal elimination of abnormal elastic fibers. This condition classically presents as small papules arranged in serpiginous or annular patterns on the neck, face, arms, or other flexural areas. While these lesions may spontaneously resolve, they often persist for longer periods of time. Though numerous treatment modalities have been described in the literature, most are not very effective. A 35-year-old man presented to Gangnam Severance Hospital with a 2-year history of skin eruptions on his neck, which were refractory to topical antifungal or steroid treatment. On examination, the patient showed multiple crusted and erythematous papules arranged in an annular pattern with central clearing. A biopsy specimen revealed acanthosis with notable transepidermal elimination of nuclear debris and eosinophilic degenerated elastic fibers from the dermis via an epidermal channel. Verhoeff-van Gieson staining showed dense clumps of altered elastic fibers in the papillary dermis. Based on these findings, a diagnosis of elastosis perforans serpisinosa was made. Treatment with topical 0.05% tretinoin application for 6 months resulted in no improvement.

D-Penicillamine induced elastosis perforans serpiginosa with involvement of glans penis

Elastosis perforans serpiginosa (EPS) is an unusual perforating disorder characterized by extrusion of altered elastic fibers through the epidermis. Clinically, it presents as keratotic papules with a tendency for serpiginous or annular distribution that most commonly involves the sides of the neck and the back. However, involvement of the penis has rarely been reported. We present a case of EPS involving the neck, axilla, and glans penis in a 42-year-old man who had received long-term d -penicillamine treatment for Wilson disease. Skin biopsy revealed perforating channels containing numerous altered elastic fibers, with a characteristic “bramble brush” or “lumpy-bumpy” appearance as demonstrated by an elastin stain. The latter is thought to be pathognomonic for penicillamine-induced degenerative elastosis. These degenerative changes occurring in glans penis have rarely been described in the literature. Prompt recognition of the rare presentation could lead to early discontinuation of the offending drug, to prevent further sequelae.

A new objective histological scale for studying human photoaged skin

A quantitative understanding of the histological alteration of the skin is important for assessing the severity of photoaging. We performed Elastica-van Gieson staining and immunohistochemistry for decorin on 34 facial skin sections. We evaluated the alteration of collagen fibers and decorin (a modulator for collagen fibrillogenesis), according to the 5 grades of morphological change in elastic fibers that was established by Kligman (1969). The objectivity of a stage (Stages I-VI), which was established in this study, was evaluated using weighted kappa statistical analysis based on the degree of agreement in stage determination by 11 observers using a blind procedure. Correlation between the crow's-feet-area wrinkles grades of another 26 women and stages was also analyzed. The initial alteration of elastic fibers was observed in the deep dermis. Decorin was not detected in very severely altered skin. Based on the combination of changes in the elastic fibers, collagenic fibers, and decorin, skin tissues were categorized into 6 stages according to severity. The statistical analysis showed almost perfect agreement between observers. Significant positive correlation between stages and wrinkle scores was found. We propose a new objective histological scale that is useful for assessing the severity of photoaging.

Aneurysm of the thoracic and abdominal aorta in a patient aged 67 years detected incidentally in pre-anesthesia consultation

An aneurysm is a localized irreversible dilatation of the aortic wall resulting from an alteration of elastic fibers in the media. The main risk is rupture. It depends on the size and growth rate. Abdominal ultrasound has become the easiest and most reproducible for screening, only the anteroposterior and transverse diameters must be selected. We report the case of patient a 67 years old, saw pre-anesthesia consultation revealed fortuitously an aneurysm of the ascending aorta of 7.5 cm diameter, 5.7 cm of the descending thoracic aorta, and 6.3 cm of the abdominal aorta below the renal arteries associated with thrombus.the patient is referred by treatment to the cardiovascular consultation, to discuss the treatment of aneurysm first before any surgery.

A New Objective Histological Scale for Studying Human Photoaged skin

Background A quantitative understanding of the histological alteration of the skin is important for assessing the severity of photoaging. Methods We performed Elastica-van Gieson staining and immunohistochemistry for decorin on 34 facial skin sections. We evaluated the alteration of collagen fibers and decorin (a modulator for collagen fibrillogenesis), according to the 5 grades of morphological change in elastic fibers that was established by Kligman (1969). The objectivity of a stage (Stages I–VI), which was established in this study, was evaluated using weighted kappa statistical analysis based on the degree of agreement in stage determination by 11 observers using a blind procedure. Correlation between the crow's-feet-area wrinkles grades of another 26 women and stages was also analyzed. Results The initial alteration of elastic fibers was observed in the deep dermis. Decorin was not detected in very severely altered skin. Based on the combination of changes in the elastic fibers, collagenic fibers, and decorin, skin tissues were categorized into 6 stages according to severity. The statistical analysis showed almost perfect agreement between observers. Significant positive correlation between stages and wrinkle scores was found. Conclusions We propose a new objective histological scale that is useful for assessing the severity of photoaging.

The Inflammatory Preatherosclerotic Remodeling Induced by Intermittent Hypoxia Is Attenuated by RANTES/CCL5 Inhibition

The highly prevalent obstructive sleep apnea syndrome (OSA) with its main component intermittent hypoxia (IH) is a risk factor for cardiovascular mortality. The poor knowledge of its pathophysiology has limited the development of specific treatments, whereas the gold standard treatment, continuous positive airway pressure, may not fully reverse the chronic consequences of OSA and has limited acceptance in some patients. To examine the contribution of IH-induced inflammation to the cardiovascular complications of OSA. We investigated systemic and vascular inflammatory changes in C57BL6 mice exposed to IH (21-5% Fi(O(2)), 60-s cycle) or normoxia 8 hours per day up to 14 days. Vascular alterations were reassessed in mice treated with a blocking antibody of regulated upon activation, normal T-cell expressed and secreted (RANTES)/CC chemokine ligand 5 (CCL5) signaling pathway, or with the IgG isotype control throughout the IH exposure. IH induced systemic inflammation combining increased splenic lymphocyte proliferation and chemokine expression, with early and predominant RANTES/CCL5 alterations, and enhanced splenocyte migration toward RANTES/CCL5. IH also induced structural and inflammatory vascular alterations. Leukocyte-endothelium adhesive interactions were increased, attested by leukocyte rolling and intercellular adhesion molecule-1 expression in mesenteric vessels. Aortas had increased intima-media thickness with elastic fiber alterations, mucoid depositions, nuclear factor-κB-p50 and intercellular adhesion molecule-1 overexpression, hypertrophy of smooth-muscle cells overexpressing RANTES/CCL5, and adventitial-periadventitial T-lymphocyte infiltration. RANTES/CCL5 neutralization prevented both intima-media thickening and inflammatory alterations, independently of the IH-associated proatherogenic dyslipidemia. Inflammation is a determinant mechanism for IH-induced preatherosclerotic remodeling involving RANTES/CCL5, a key chemokine in atherogenesis. Characterization of the inflammatory response could allow identifying at-risk patients for complications, and its pharmacologic manipulation may represent a potential complementary treatment of sleep apnea consequences.

Alterations of elastic fibers in genetically modified mice and human genetic diseases

The two main components of elastic fibers are elastin and microfibrils. Fibrillin and microfibrillar-associated glycoproteins are the essential constituents of microfibrils. In the last ten years, the analysis of genetically modified mice and human genetic diseases has led to the observation that, besides elastin, fibrillins and microfibrillar-associated proteins, numerous other molecules play an essential role in the supramolecular organisation of the elastic fibers in the extracellular space and in the interactions between elastic fibers and cells. These recent data are summarized in this review.

Pseudoxantoma elástico perfurante periumbilical e periareolar

The periumbilical perforating pseudoxanthoma elasticum or perforating calcific elastosis is a rare disorder and its pathogenesis is associated with the alteration of elastic fibers, which may probably result from trauma. We present the case of a 70-year-old woman with long-time blackish maculas and keratotic surface papules on the periareolar and periumbilical regions. The histopathological examination revealed altered elastic fibers, replete with calcium and formation of a path in the dermis with elastic fibers degraded in their interior, confirming the clinical diagnosis.

Alterations of elastic fibers in genetically modified mice and human genetic diseases

Alterations of elastic fibers in genetically modified mice and human genetic diseases