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Reconstruction
Published in Karl H. Pang, Nadir I. Osman, James W.F. Catto, Christopher R. Chapple, Basic Urological Sciences, 2021
Nadir I. Osman, Karl H. Pang, Christopher R. Chapple
Full-thickness skin grafts (FTSG) features:Include entire epidermis and dermis.Less prone to secondary contraction (contraction that occurs after graft transferred to recipient site).Based on subdermal plexus − tenuous vascularity.Include the reticular dermis − favourable mechanical properties.
Comparative Anatomy, Physiology, and Biochemistry of Mammalian Skin
Published in David W. Hobson, Dermal and Ocular Toxicology, 2020
Elastic fibers found in the reticular dermis of man are coarser and thicker than those of the papillary layer, which branch repeatedly. Fine branches of the elastic fibers of the papillary layer extend to the basal lamina of the epidermis where they terminate as knob-like (globose) endings. Elastic fibers in the papillary layer of cheeks, eyebrows, and chins of humans are tightly woven around blood vessels. In the fingers, toes, palms, and soles, elastic fibers are very dense in the papillary layer and may surround individual Meissner corpuscles. Elastic fibers are found to run in various directions in the reticular dermis. In some areas, i.e., chest, thighs, axilla, breast, mons pubis, gluteal region, and abdomen, coarse elastic fibers run parallel to the surface in the reticular layer. In the skin of the chest, axilla, and mons pubis, some elastic fibers run up into the papillary layer from the reticular layer and form arcades in which straight branches radiate toward the epidermis.207
Skin Perforation and Solid Microneedles
Published in Boris Stoeber, Raja K Sivamani, Howard I. Maibach, Microneedling in Clinical Practice, 2020
Michael L Crichton, Mark Kendall
Below the epidermis sits the dermis—a rich mesh of collagen, blood capillaries, cells, hair/sebum follicles, and nerve endings, embedded in a proteoglycan and hyaluronic acid gel (5). This layer can be further split into the papillary dermis (the upper dermis around the base of the epidermis) and the reticular dermis (the lower dermis). The papillary dermis has a finer mesh of collagen than the reticular dermis and contains smaller capillary ends; the reticular dermis has larger collagen bundles forming its structure and large capillaries (6). This composition means that the tissue has a range of properties that can challenge the engineer looking to deliver drugs or vaccine within. The collagen fibers in particular give an overall structural strength to the skin that enables it to be flexible but hard to puncture.
Skin proteomics – analysis of the extracellular matrix in health and disease
Published in Expert Review of Proteomics, 2020
Jörn Dengjel, Leena Bruckner-Tuderman, Alexander Nyström
The second important skin layer is the dermis (Figure 1). It provides tensile strength, elasticity, and resilience to the skin. Histologically the dermis can be divided into a thin superficial layer, the papillary dermis, and a thicker deeper layer, the reticular dermis. Although adnexal, vascular, lymphatic and neural structures traverse the dermis, fibroblasts constitute the major cell population embedded in the dermal connective tissue. These are ECM producing mesenchymal cells responsible for maintenance, repair, and regeneration of the dermis. Recent research data indicate that the superficial, middle, and deeper dermal layers harbor distinct fibroblast subpopulations [62], nevertheless definitive cell markers still remain elusive and functional characteristics that distinguish them are not fully understood. Quantitatively minor and changing cell populations in the dermis encompass immune cells. Upon need, they migrate into the skin and exert decisive functions in immune response, inflammation, and regenerative processes [63].
The use of energy devices in the treatment of striae: a systematic literature review
Published in Journal of Dermatological Treatment, 2019
Georgios Kravvas, David Veitch, Firas Al-Niaimi
Histologically, SD demonstrate a similar appearance to atrophic scars with epidermal atrophy, flattening of the rete ridges, loss of thickness in the dermis, as well as retraction and loss of collagen and elastin (7–9). Exact histopathological findings vary depending on the age of the lesions (1). Early lesions show superficial and deep perivascular infiltrates of lymphocytes and sometimes of eosinophils, as well as widely dilated venules and edema in the upper part of the dermis (1). Fully developed lesions show a scant infiltrate of lymphocytes around venules. Bundles of collagen in the upper third of the reticular dermis are thinned and aligned parallel to the skin surface (1). Contributing to the atrophied appearance of striae are the reduced amounts of fibrillin surrounding the dermal–epidermal junction, reduced elastin in the papillary dermis, and reorganization of elastin and fibrillin fibers in the deep dermis (10).
Anti-ageing peptides and proteins for topical applications: a review
Published in Pharmaceutical Development and Technology, 2022
Mengyang Liu, Shuo Chen, Zhiwen Zhang, Hongyu Li, Guiju Sun, Naibo Yin, Jingyuan Wen
The region immediately beneath the epidermis, and above the subcutaneous tissue, is the dermis with a thickness of up to 0.4 cm. The dermis occupies about 90% of the skin weight (Rippa et al. 2019) and has blood vessels, lymphatics, and sensory nerves. The dermis can be divided into two regions, namely the reticular dermis and papillary dermis. The reticular dermis is located below these interdigitations of epithelium, while the papillary dermis is the region of overlapping projection in the epithelium and connective tissue (Korosec et al. 2019). The dermis consists of a network of loose connective tissue (elastic tissue and collagen fibrils) embedded in mucopolysaccharides, which provide elasticity and protection to the skin.