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Anais Brasileiros de Dermatologia 2014Focal acral hyperkeratosis is a rare genodermatosis with an autosomal dominant pattern of inheritance. It is characterized by usually asymptomatic keratotic papules...
Focal acral hyperkeratosis is a rare genodermatosis with an autosomal dominant pattern of inheritance. It is characterized by usually asymptomatic keratotic papules along the borders of the hands and/or feet. The main differential diagnosis is acrokeratoelastoidosis of Costa, which differs from the former only by not presenting elastorrhexis in histopathological examination, thus requiring this exam for a correct diagnosis.
Topics: Adult; Biopsy; Dermis; Diagnosis, Differential; Female; Humans; Keratoderma, Palmoplantar
PubMed: 25184932
DOI: 10.1590/abd1806-4841.20143152 -
Wounds : a Compendium of Clinical... Jan 2020Partially avascular wounds pose a challenge to wound care surgeons. (Review)
Review
INTRODUCTION
Partially avascular wounds pose a challenge to wound care surgeons.
OBJECTIVE
The authors reviewed the literature and institutional results on the use of a dermal regenerative template (DRT) over partially avascular wounds to quantify the ability of the DRT to vascularize over these wounds.
MATERIALS AND METHODS
A review of the literature was performed using Ovid MEDLINE, Google Scholar, and Cochrane Library. Patient demographics, comorbidities, wound types, surface area of avascular tissues, and skin graft take were analyzed. A retrospective review of institutional cases was conducted.
RESULTS
A total of 32 articles met inclusion criteria. The retrospective review included 26 patients with partially avascular wounds reconstructed with the DRT. Seventeen patients experienced 100% graft take, 6 experienced partial take, and 3 suffered complete loss. The percent and absolute size of avascular surface area in the wound was significantly lower in cases of complete graft take compared with partial take and complete loss (1.9% and 2.7 cm2; 9.3% and 10.0 cm2; 18.0% and 9.3 cm2, respectively, P ⟨ .001). Chronic wound status (P ⟨ .001) was significantly associated with less graft take.
CONCLUSIONS
This literature review and retrospective study confirm the DRT is a viable option to provide vascularized coverage over wounds with avascular components. This study suggests the DRT is more reliable in wounds with less than 1.9% avascular tissues and less successful in chronic wounds.
Topics: Dermis; Graft Survival; Humans; Regeneration; Skin; Skin Physiological Phenomena; Skin Transplantation; Soft Tissue Injuries; Wound Healing
PubMed: 32155125
DOI: No ID Found -
International Journal of Molecular... May 2022Skin aging is a multi-factorial process that affects nearly every aspect of skin biology and function. The processes developing in the skin during aging are based on... (Review)
Review
Skin aging is a multi-factorial process that affects nearly every aspect of skin biology and function. The processes developing in the skin during aging are based on fundamental molecular mechanisms associated with fibroblasts, the main cellular population of the dermis. It has been revealed that the amount of fibroblasts decreases markedly with age and their functional activity is also reduced. This inevitably leads to a decrease in the regenerative abilities of the skin and the progression of its aging. In this review we consider the mechanisms underlying these processes, mainly the changes observed with age in the stem/progenitor cells that constitute the fibroblastic differon of the dermis and form their microenvironment (niches). These changes lead to the depletion of stem cells, which, in turn, leads to a decrease in the number of differentiated (mature) dermal fibroblasts responsible for the production of the dermal extracellular matrix and its remodeling. We also describe in detail DNA damages, their cellular and systemic consequences, molecular mechanisms of DNA damage response, and also the role of fibroblast senescence in skin aging.
Topics: Dermis; Extracellular Matrix; Fibroblasts; Skin; Skin Aging
PubMed: 35682813
DOI: 10.3390/ijms23116135 -
Journal of Ultrasound Mar 2023Current ultrasound (US) Doppler techniques cannot demonstrate the vascularization of the dermis. The purpose of this study was to investigate whether the new Superb...
AIMS
Current ultrasound (US) Doppler techniques cannot demonstrate the vascularization of the dermis. The purpose of this study was to investigate whether the new Superb Vascular Imaging (SMI) and Microvascular Flow (MV-Flow) techniques improve the detection of normal dermis vessels. SMI and MV-Flow were compared side-by-side to conventional power-Doppler (PD) imaging.
METHODS
By using US, 50 healthy volunteers were evaluated at level of five body areas: forehead, forearm, palm, buttock, and thigh. Two off-site operators evaluated the images to assess the difference between SMI and PD imaging and between MV-Flow and PD imaging in terms of dermis flow amount. A 0-3 scoring system was adopted.
RESULTS
SMI scored grade 0 in 0% of body areas, grade 1 in 58%, grade 2 in 33%, and grade 3 in 9%. In comparison with SMI, PD scored grade 0 in 38% of body areas, grade 1 in 56%, grade 2 in 6%, and grade 3 in 0%. MV-Flow scored grade 0 in 0% of body areas, grade 1 in 52%, grade 2 in 43%, and grade 3 in 6%. Comparted to MV-Flow, PD scored grade 0 in 53% of body areas, grade 1 in 34%, grade 2 in 13%, and grade 3 in 0%. The difference in terms of sensitivity was statistically significant for all the body areas investigated.
CONCLUSIONS
We found both SMI and MV-Flow to be superior to PD imaging and capable to demonstrate normal vascularization of the dermis.
Topics: Humans; Microcirculation; Microvessels; Ultrasonography, Doppler; Ultrasonography; Dermis
PubMed: 36001281
DOI: 10.1007/s40477-022-00710-2 -
Cell and Tissue Research Feb 2023The generation and growing of de novo hair follicles is the most daring hair replacement approach to treat alopecia. This approach has been explored at least since the... (Review)
Review
The generation and growing of de novo hair follicles is the most daring hair replacement approach to treat alopecia. This approach has been explored at least since the 1960s without major success. Latest in the 1980s, the realization that the mesenchymal compartment of hair follicles, the dermal papilla (DP), is the crucial signaling center and element required for fulfilling this vision of hair follicle engineering, propelled research into the fibroblasts that occupy the DP. However, working with DP fibroblasts has been stubbornly frustrating. Decades of work in understanding the nature of DP fibroblasts in vitro and in vivo have led to the appreciation that hair follicle biology is complex, and the dermal papilla is an enigma. Functional DP fibroblasts tend to aggregate in 2D culture, while impaired DP cells do not. This fact has stimulated recent approaches to overcome the hurdles to DP cell culture by mimicking their natural habitat, such as growing DP fibroblasts in three dimensions (3D) by their self-aggregation, adopting 3D matrix scaffold, or bioprinting 3D microstructures. Furthermore, including keratinocytes in the mix to form hair follicle-like composite structures has been explored but remains a far cry from a useful and affordable method to generate human hair follicles in sufficient quantity and quality in a practical time frame for patients. This suggests that the current strategies may have reached their limitations in achieving successful hair follicle bioengineering for clinical applications. Novel approaches are required to overcome these barriers, such as focusing on embryonic cell types and processes in combination with emerging techniques.
Topics: Humans; Hair Follicle; Dermis; Cells, Cultured; Keratinocytes; Bioengineering
PubMed: 36562864
DOI: 10.1007/s00441-022-03730-w -
The Journal of Investigative Dermatology Feb 2018There is an increasing interest in the apparently normal skin in vitiligo. Altered expression of the adhesion molecule E-cadherin and persistent deregulated...
There is an increasing interest in the apparently normal skin in vitiligo. Altered expression of the adhesion molecule E-cadherin and persistent deregulated intracellular redox status that promotes the acquisition of a stress-induced senescent phenotype in melanocytes of normally pigmented skin from patients with vitiligo have been described. Growing evidence has shown that such cellular and functional alterations are not necessarily restricted to melanocytes but may be extended to other cutaneous cell populations in both lesional and nonlesional areas. However, whether dermal fibroblasts exhibit related alterations that may contribute to the defects associated with melanocytes in vitiligo is not known. Here we reveal within the dermal compartment cells a myofibroblast phenotype and a predisposition to premature senescence, indicating the existence of altered cross-talk between dermal and epidermal components that may affect melanocyte functionality even in the apparently normal skin of patients with vitiligo.
Topics: Adult; Aged; Biopsy; Cell Communication; Cell Separation; Cellular Senescence; Dermis; Epidermis; Female; Flow Cytometry; Healthy Volunteers; Humans; Male; Melanocytes; Middle Aged; Myofibroblasts; Primary Cell Culture; Reactive Oxygen Species; Vitiligo
PubMed: 29024688
DOI: 10.1016/j.jid.2017.06.033 -
Journal of Cosmetic Dermatology Feb 2020Chronological skin aging causes the modification of genetic material through enzymes and proteins changes. The process reduces cellular proliferation, along with loss of... (Review)
Review
BACKGROUND
Chronological skin aging causes the modification of genetic material through enzymes and proteins changes. The process reduces cellular proliferation, along with loss of tissue elasticity, reduced ability to regulate aqueous exchanges, and inefficient tissue replication. Appearance is negatively affected by cumulative changes in coloration, texture, and elasticity over time. The increase in the population's average life expectancy boosts the search for cosmetic therapies that can delay aging, mostly for the noninvasive modalities. Among the various options, radiofrequency therapy is a technique that can help reduce the effects of skin aging.
AIM
Therefore, this study aims to review clinical evidence provided by scientific literature on the benefits of using radiofrequency therapy in reducing skin aging effects.
METHODS
A review of the literature concerning skin aging, characteristics of radiofrequency therapy, and radiofrequency therapy in the treatment of skin laxity and mechanism of action was conducted using PubMed.
RESULTS
The included studies have suggested that the mechanism of radiofrequency action is heating the dermis while preserving the epidermis. This heating causes immediate collagen denaturation, which is followed by the formation of new collagen, naturally providing skin tightening and greater elasticity.
CONCLUSION
Even when used as single therapeutic modality, radiofrequency seems to meet the expectations in reducing the effects of skin aging.
Topics: Collagen; Cosmetic Techniques; Dermatology; Dermis; Elasticity; Electrodes; Epidermis; Evidence-Based Medicine; Humans; Protein Denaturation; Radiofrequency Therapy; Skin Aging; Treatment Outcome
PubMed: 31691477
DOI: 10.1111/jocd.13206 -
The Journal of Investigative Dermatology Apr 2021As a barrier organ, the skin is an ideal model to study environmentally-induced (extrinsic) aging. In this review, we explain the development of extrinsic skin aging as... (Review)
Review
As a barrier organ, the skin is an ideal model to study environmentally-induced (extrinsic) aging. In this review, we explain the development of extrinsic skin aging as a consequence of skin exposure to specific exposomal factors, their interaction with each other, and the modification of their effects on the skin by genetic factors. We also review the evidence that exposure to these exposomal factors causes extrinsic skin aging by mechanisms that critically involve the accumulation of macromolecular damage and the subsequent development of functionally altered and/or senescent fibroblasts in the dermal compartment of the skin.
Topics: Air Pollutants; Cellular Senescence; DNA Damage; Dermis; Environmental Exposure; Fibroblasts; Humans; Skin Aging; Ultraviolet Rays
PubMed: 33541724
DOI: 10.1016/j.jid.2020.12.011 -
Acta Biomaterialia Mar 2019Skin, the outermost layer of the body, fulfills a broad range of functions, protecting internal organs from damage and infection, while regulating the body's temperature...
Skin, the outermost layer of the body, fulfills a broad range of functions, protecting internal organs from damage and infection, while regulating the body's temperature and water content via the exchange of heat and fluids. It must be able to withstand and recover from extensive deformation and damage that can occur during growth, movement, and potential injuries. A detailed investigation of the evolution of the collagen architecture of the dermis as a function of deformation is conducted, which reveals new aspects that help us to understand the mechanical response of skin. Juvenile pig is used as a model material because of its similarity to human skin. The dermis is found to have a tridimensional woven structure of collagen fibers, which evolves with deformation. After failure, we observe that the fibers have straightened and aligned in the direction of tension. The effects of strain-rate change, cyclic loading, stress relaxation, and orientation are quantitatively established. Digital image correlation techniques are implemented to quantify skin's anisotropy; measurements of the Poisson ratio are reported. This is coupled with transmission electron microscopy which enables obtaining quantitative strain parameters evaluated through the orientation and curvature of the collagen fibers and their changes, for the first time in all three dimensions of the tissue. A model experiment using braided human hair in tension exhibits a similar J-curve response to skin, and we propose that this fiber configuration is at least partially responsible for the monotonic increase of the tangent modulus of skin with strain. The obtained results are intended to serve as a basis for structurally-based models of skin. STATEMENT OF SIGNIFICANCE: Our study reveals a new aspect of the dermis: it is comprised of a tridimensional woven structure of collagen fibers, which evolves with deformation. This is enabled by primarily two techniques, transmission electron microscopy on three perpendicular planes and confocal images with second harmonic generation fluorescence of collagen, captured at different intervals of depth. After failure, the fibers have straightened and aligned in the direction of tension. Digital image correlation techniques are implemented to quantify skin's anisotropy; measurements of the Poisson ratio are reported. A model experiment using braided human hair in tension exhibits a similar J-curve response to skin, and we propose that this fiber configuration is at least partially responsible for the monotonic increase of the tangent modulus of skin with strain.
Topics: Animals; Dermis; Fibrillar Collagens; Humans; Regression Analysis; Stress, Mechanical; Swine; Tensile Strength
PubMed: 30660003
DOI: 10.1016/j.actbio.2019.01.023 -
Advanced Healthcare Materials May 2018A novel, pure, synthetic material is presented that promotes the repair of full-thickness skin wounds. The active component is tropoelastin and leverages its ability to...
A novel, pure, synthetic material is presented that promotes the repair of full-thickness skin wounds. The active component is tropoelastin and leverages its ability to promote new blood vessel formation and its cell recruiting properties to accelerate wound repair. Key to the technology is the use of a novel heat-based, stabilized form of human tropoelastin which allows for tunable resorption. This implantable material contributes a tailored insert that can be shaped to the wound bed, where it hydrates to form a conformable protein hydrogel. Significant benefits in the extent of wound healing, dermal repair, and regeneration of mature epithelium in healthy pigs are demonstrated. The implant is compatible with initial co-treatment with full- and split-thickness skin grafts. The implant's superiority to sterile bandaging, commercial hydrogel and dermal regeneration template products is shown. On this basis, a new concept for a prefabricated tissue repair material for point-of-care treatment of open wounds is provided.
Topics: Absorbable Implants; Animals; Autografts; Blood Vessels; Dermis; Humans; Hydrogel, Polyethylene Glycol Dimethacrylate; Mice; Swine; Tissue Scaffolds; Tropoelastin; Wound Healing
PubMed: 29450975
DOI: 10.1002/adhm.201701206