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Cells Jun 2019There are many studies on certain skin cell specifications and their contribution to wound healing. In this review, we provide an overview of dermal cell heterogeneity... (Review)
Review
There are many studies on certain skin cell specifications and their contribution to wound healing. In this review, we provide an overview of dermal cell heterogeneity and their participation in skin repair, scar formation, and in the composition of skin substitutes. The papillary, reticular, and hair follicle associated fibroblasts differ not only topographically, but also functionally. Human skin has a number of particular characteristics that are different from murine skin. This should be taken into account in experimental procedures. Dermal cells react differently to skin wounding, remodel the extracellular matrix in their own manner, and convert to myofibroblasts to different extents. Recent studies indicate a special role of papillary fibroblasts in the favorable outcome of wound healing and epithelial-mesenchyme interactions. Neofolliculogenesis can substantially reduce scarring. The role of hair follicle mesenchyme cells in skin repair and possible therapeutic applications is discussed. Participation of dermal cell types in wound healing is described, with the addition of possible mechanisms underlying different outcomes in embryonic and adult tissues in the context of cell population characteristics and extracellular matrix composition and properties. Dermal white adipose tissue involvement in wound healing is also overviewed. Characteristics of myofibroblasts and their activity in scar formation is extensively discussed. Cellular mechanisms of scarring and possible ways for its prevention are highlighted. Data on keloid cells are provided with emphasis on their specific characteristics. We also discuss the contribution of tissue tension to the scar formation as well as the criteria and effectiveness of skin substitutes in skin reconstruction. Special attention is given to the properties of skin substitutes in terms of cell composition and the ability to prevent scarring.
Topics: Animals; Cicatrix; Dermis; Extracellular Matrix; Fibroblasts; Hair Follicle; Humans; Keloid; Myofibroblasts; Regeneration; Skin; Skin Physiological Phenomena; Skin, Artificial; Wound Healing
PubMed: 31216669
DOI: 10.3390/cells8060607 -
Indian Journal of Dermatology,... 2013Interface dermatitis includes diseases in which the primary pathology involves the dermo-epidermal junction. The salient histological findings include basal cell... (Review)
Review
Interface dermatitis includes diseases in which the primary pathology involves the dermo-epidermal junction. The salient histological findings include basal cell vacuolization, apoptotic keratinocytes (colloid or Civatte bodies), and obscuring of the dermo-epidermal junction by inflammatory cells. Secondary changes of the epidermis and papillary dermis along with type, distribution and density of inflammatory cells are used for the differential diagnoses of the various diseases that exhibit interface changes. Lupus erythematosus, dermatomyositis, lichen planus, graft versus host disease, erythema multiforme, fixed drug eruptions, lichen striatus, and pityriasis lichenoides are considered major interface diseases. Several other diseases (inflammatory, infective, and neoplastic) may show interface changes.
Topics: Dermatitis; Dermatology; Dermis; Epidermis; Humans; Lichenoid Eruptions
PubMed: 23619439
DOI: 10.4103/0378-6323.110780 -
Clinical, Cosmetic and Investigational... 2015Microfocused ultrasound (MFU) has been recently developed to meet the ever-growing public demand for achieving significant, noninvasive skin lifting and tightening. MFU... (Review)
Review
Microfocused ultrasound (MFU) has been recently developed to meet the ever-growing public demand for achieving significant, noninvasive skin lifting and tightening. MFU can be focused on subcutaneous tissue where the temperature briefly reaches greater than 60°C, producing small (<1 mm(3)) thermal coagulation points to a depth of up to 5 mm within the mid-to-deep reticular layer of the dermis and subdermis. The intervening papillary dermal and epidermal layers of skin remain unaffected. The application of heat at these discrete thermal coagulation points causes collagen fibers in the facial planes such as the superficial musculoaponeurotic system and platysma, as well as the deep reticular dermis, to become denatured, contracting and stimulating de novo collagen. A commercially available device combines MFU with high-resolution ultrasound imaging (MFU-V), which enables visualization of tissue planes to a depth of 8 mm and allows the user to see where the MFU energy will be applied (Ultherapy(®); Ulthera Inc., Mesa, AZ, USA). Using different transducers, MFU-V treatment can be customized to meet the unique physical characteristics of each patient by adjusting energy and focal depth of the emitted ultrasound. By targeting the facial superficial musculoaponeurotic system, noninvasive tightening and lifting of sagging facial and neck skin and improvements in the appearance of wrinkles can be achieved. MFU-V can also improve lines and wrinkles of the décolleté. Treatment protocols for the use of MFU-V continue to be refined, and its use in combination with other rejuvenation techniques has been demonstrated. Brief discomfort that often occurs during treatment can be minimized with oral nonsteroidal anti-inflammatory drugs. Other treatment-related adverse events include transient erythema, edema, and occasional bruising. MFU-V is best suited for patients with mild-to-moderate skin and soft tissue laxity. For older patients with severe skin laxity and marked platysmal banding, surgical treatment should be considered.
PubMed: 25709486
DOI: 10.2147/CCID.S69118 -
American Journal of Clinical Dermatology May 2021Dermatitis herpetiformis (DH), presenting with an intense itch and blistering symmetrical rash, typically on the elbows, knees, and buttocks, is a cutaneous... (Review)
Review
Dermatitis herpetiformis (DH), presenting with an intense itch and blistering symmetrical rash, typically on the elbows, knees, and buttocks, is a cutaneous manifestation of celiac disease. Though overt gastrointestinal symptoms are rare, three-fourths of patients with DH have villous atrophy in the small bowel, and the rest have celiac-type inflammatory changes. DH affects mostly adults and slightly more males than females. The mean age at onset is about 50 years. DH diagnosis is confirmed by showing granular immunoglobulin A deposits in the papillary dermis. The DH autoantigen, transglutaminase 3, is deposited at the same site in tightly bound immune complexes. At present, the DH-to-celiac disease prevalence is 1:8. The incidence of DH is decreasing, whereas that of celiac disease is increasing, probably because of improved diagnostics. In DH, the treatment of choice for all patients is a gluten-free diet (GFD) in which uncontaminated oats are allowed. At onset, most patients need additional dapsone to rapidly control the rash and itching. Dapsone can be stopped after a mean of 2 years, and a strict lifelong GFD alone is required. Dietary adherence offers an excellent long-term prognosis for patients with DH, with a normal quality of life and all-cause mortality.
Topics: Adult; Age Factors; Celiac Disease; Combined Modality Therapy; Dapsone; Dermatitis Herpetiformis; Dermis; Diet, Gluten-Free; Female; Humans; Immunoglobulin A; Intestinal Mucosa; Intestine, Small; Male; Patient Compliance; Prevalence; Prognosis; Quality of Life; Risk Factors; Sex Factors; Treatment Outcome
PubMed: 33432477
DOI: 10.1007/s40257-020-00584-2 -
Giornale Italiano Di Dermatologia E... Jun 2020The skin is a dynamic organ that continuously eliminates an infinite number of keratinized cells through physiological mechanism. Chemical peeling is a widely used... (Review)
Review
The skin is a dynamic organ that continuously eliminates an infinite number of keratinized cells through physiological mechanism. Chemical peeling is a widely used cosmetic procedure in medical practice. This technique consists of the application of one or more chemical ablative agents to the skin's surface in order to induce keratolysis or keratocoagulation. Exfoliation is followed by skin and epidermal regeneration from the adjacent epithelium and skin adnexa. Moreover, through an inflammatory reaction and the activation of the inflammation mediators, an increase in fibroblastic synthesis and in the production of new collagen and glycosaminoglycan fibers is induced. After the first treatment session, the appearance and the texture of the skin are significantly improved. Peeling agents may be divided into superficial (epidermis-papillary dermis), medium-depth (papillary to upper reticular dermis) and deep subtypes based on the depth of their penetration (mid-reticular dermis). Superficial peel is mainly used for dyschromia, acne, post-inflammatory hyperpigmentation, melasma and actinic keratosis. Medium depth peel mainly treats solar keratosis or lentigines, pigmentary disorders and superficial scars. Skin photo-ageing, deep scars or wrinkles and precancerous skin lesions require a deep chemical peeling. The aim of this article is to review recent advances in chemical peel of melasma and acne.
Topics: Acne Vulgaris; Chemexfoliation; Cicatrix; Humans; Hyperpigmentation; Keratolytic Agents; Melanosis; Skin Aging; Skin Diseases
PubMed: 31804050
DOI: 10.23736/S0392-0488.19.06425-3 -
Mechanisms of Ageing and Development Jan 2019Ageing is today a major societal concern that is intrinsically associated with the increase of life expectancy. Outside the context of severe degenerative diseases that... (Review)
Review
Ageing is today a major societal concern that is intrinsically associated with the increase of life expectancy. Outside the context of severe degenerative diseases that affect the elderly populations, normal visible signs of ageing, notably skin sagging and wrinkles, influence the social and individual perception of peoples. Accordingly, there is a strong demand for researches on skin ageing. Deciphering the cellular and molecular processes of skin evolution through ageing is thus an active scientific domain, at the frontier of tissue developmental and ageing biology. The focus of the present article is to provide an overview of the current knowledge concerning the evolution of dermis characteristics at different life stages, from intra-uterine to post-natal life. The description will integrate stage-specific and age-related changes in dermis characteristics at the tissue, cell, and molecular levels.
Topics: Aging; Animals; Dermis; Extracellular Matrix; Humans; Skin Aging
PubMed: 29548941
DOI: 10.1016/j.mad.2018.03.006 -
Cells Feb 2020Human skin dermis contains fibroblast subpopulations in which characterization is crucial due to their roles in extracellular matrix (ECM) biology. This study...
Fibroblasts from the Human Skin Dermo-Hypodermal Junction are Distinct from Dermal Papillary and Reticular Fibroblasts and from Mesenchymal Stem Cells and Exhibit a Specific Molecular Profile Related to Extracellular Matrix Organization and Modeling.
Human skin dermis contains fibroblast subpopulations in which characterization is crucial due to their roles in extracellular matrix (ECM) biology. This study investigates the properties of fibroblasts localized at the frontier of deep dermis and hypodermis, i.e., dermo-hypodermal junction fibroblasts (F-DHJ), which were compared to intermediate reticular dermis (Fr) and superficial papillary dermis (Fp) fibroblasts. F-DHJ differed from Fr and Fp cells in their wider potential for differentiation into mesodermal lineages and in their absence of contractility when integrated in a three-dimensional dermal equivalent. The transcriptomic profile of F-DHJ exhibited specificities in the expression of genes involved in ECM synthesis-processing and "tissue skeleton" organization. In accordance with transcriptome data, ECM proteins, notably Tenascin C, distributions differed between the reticular dermis and the dermo-hypodermal junction areas, which was documented in normal adult skin. Finally, genome-wide transcriptome profiling was used to evaluate the molecular proximity of F-DHJ with the two dermal fibroblast populations (Fp and Fr) and with the mesenchymal stem cells (MSCs) corresponding to five tissue origins (bone marrow, fat, amnion, chorion, and cord). This comparative analysis classified the three skin fibroblast types, including F-DHJ, as a clearly distinct group from the five MSC sample origins.
Topics: Adolescent; Adult; Aged; Aging; Biomarkers; Cell Differentiation; Cell Lineage; Cell Proliferation; Cell Shape; Dermis; Extracellular Matrix; Female; Fibroblasts; Humans; Mesenchymal Stem Cells; Middle Aged; Models, Biological; Phenotype; RNA, Messenger; Tenascin; Transcriptome; Young Adult
PubMed: 32033496
DOI: 10.3390/cells9020368