"Beare–Stevenson cutis gyrata syndrome Beare–Stevenson cutis gyrata syndrome is a rare genetic disorder characterized by craniosynostosis (premature fusion of certain bones of the skull, sometimes resulting in a characteristic 'cloverleaf skull'; further growth of the skull is prevented, and therefore the shape of the head and face is abnormal) and a specific skin abnormality, called cutis gyrata, characterized by a furrowed and wrinkled appearance (particularly in the face and on the palms and soles of the feet); thick, dark, velvety areas of skin (acanthosis nigricans) are sometimes found on the hands and feet and in the groin. Additional signs and"
"organ of the body. In humans, it accounts for about 12 to 15 percent of total body weight and covers 1.5-2m of surface area. The human skin (integument) is composed of at least two major layers of tissue: the epidermis and dermis. (The hypodermis or subcutaneous layer is not part of the skin.) The epidermis is the outermost layer, providing the initial barrier to the external environment. Beneath this, the dermis comprises two sections, the papillary and reticular layers, and contains connective tissues, vessels, glands, follicles, hair roots, sensory nerve endings, and muscular tissue. The deepest layer, the hypodermis, is"
"and receives its name from the dense concentration of collagenous, elastic, and reticular fibers that weave throughout it. These protein fibers give the dermis its properties of strength, extensibility, and elasticity. Also located within the reticular region are the roots of the hair, sweat glands, sebaceous glands, receptors, nails, and blood vessels. The subcutaneous tissue (also hypodermis) is not part of the skin, and lies below the dermis. Its purpose is to attach the skin to underlying bone and muscle as well as supplying it with blood vessels and nerves. It consists of loose connective tissue and elastin. The main"
"corneum. The dermis is the layer of skin between the epidermis and subcutaneous tissue, and comprises two sections, the papillary dermis and the reticular dermis. The superficial papillary dermis interdigitates with the overlying rete ridges of the epidermis, between which the two layers interact through the basement membrane zone. Structural components of the dermis are collagen, elastic fibers, and ground substance also called extra fibrillar matrix. Within these components are the pilosebaceous units, arrector pili muscles, and the eccrine and apocrine glands. The dermis contains two vascular networks that run parallel to the skin surface—one superficial and one deep plexus—which"
"of the epidermis. The word epidermis is derived through Latin , itself and . Something related to or part of the epidermis is termed epidermal. The human epidermis is a familiar example of epithelium, particularly a stratified squamous epithelium The epidermis primarily consists of keratinocytes (proliferating basal and differentiated suprabasal), which comprise 90% of its cells, but also contains melanocytes, Langerhans cells, Merkel cells, and inflammatory cells. Epidermal thickenings called Rete ridges (or rete pegs) extend downward between dermal papillae. Blood capillaries are found beneath the epidermis, and are linked to an arteriole and a venule. The epidermis itself has"
"the epidermis are keratinocytes, melanocytes, Langerhans cells and Merkel cells. The epidermis helps the skin to regulate body temperature. Epidermis is divided into several layers where cells are formed through mitosis at the innermost layers. They move up the strata changing shape and composition as they differentiate and become filled with keratin. They eventually reach the top layer called ""stratum corneum"" and are sloughed off, or desquamated. This process is called ""keratinization"" and takes place within weeks. The outermost layer of the epidermis consists of 25 to 30 layers of dead cells. Epidermis is divided into the following 5 sublayers"
"the dorsal portion of the paraxial mesoderm somite which gives rise to the skin (dermis). In the human embryo it arises in the third week of embryogenesis. It is formed when a dermamyotome (the remaining part of the somite left when the sclerotome migrates), splits to form the dermatome and the myotome. The dermatomes contribute to the skin, fat and connective tissue of the neck and of the trunk, though most of the skin is derived from lateral plate mesoderm. The myotome is that part of a somite that forms the muscles of the animal. Each myotome divides into an"
"skin-like tissue grown in a laboratory, although this technology is still quite a way away from being viable for use in the medical field. 'Artificial skin' can also refer to flexible semiconductor materials that can sense touch for those with prosthetic limbs, (also experimental). The skin is the largest organ in the human body. Skin is made up of three layers, the epidermis, dermis and the fat layer, also called the hypodermis. The epidermis is the outer layer of skin that keeps vital fluids in and harmful bacteria out of the body. The dermis is the inner layer of skin"
"and thermoreceptors that provide the sense of heat. In addition, hair follicles, sweat glands, sebaceous glands, apocrine glands, lymphatic vessels and blood vessels are present in the dermis. Those blood vessels provide nourishment and waste removal for both dermal and epidermal cells. The dermis is composed of three major types of cells: fibroblasts, macrophages, and adipocytes. Apart from these cells, the dermis is also composed of matrix components such as collagen (which provides strength), elastin (which provides elasticity), and extrafibrillar matrix, an extracellular gel-like substance primarily composed of glycosaminoglycans (most notably hyaluronan), proteoglycans, and glycoproteins. The papillary dermis is the"
"the need so arises. There are two important layers to the human skin: (1) the Epidermis and (2) the Dermis. For transdermal delivery, drugs must pass through the two sublayers of the epidermis to reach the microcirculation of the dermis. The Stratum corneum is the top layer of the skin and varies in thickness from approximately ten to several hundred micrometres, depending on the region of the body. It is composed of layers of dead, flattened keratinocytes surrounded by a lipid matrix, which together act as a brick-and-mortar system that is difficult to penetrate. The stratum corneum provides the most"
"type. Glomus body A glomus body (or glomus apparatus) is a component of the dermis layer of the skin, involved in body temperature regulation. The glomus body consists of an arteriovenous shunt surrounded by a capsule of connective tissue. Glomus bodies are most numerous in the fingers and toes. The role of the glomus body is to shunt blood away from the skin surface when exposed to cold temperature, thus preventing heat loss, and allowing maximum heat flow to the skin in warm weather to allow heat to dissipate. The glomus body has high sympathetic tone and potentiation leads to"
"Glomus body A glomus body (or glomus apparatus) is a component of the dermis layer of the skin, involved in body temperature regulation. The glomus body consists of an arteriovenous shunt surrounded by a capsule of connective tissue. Glomus bodies are most numerous in the fingers and toes. The role of the glomus body is to shunt blood away from the skin surface when exposed to cold temperature, thus preventing heat loss, and allowing maximum heat flow to the skin in warm weather to allow heat to dissipate. The glomus body has high sympathetic tone and potentiation leads to near"
"area called the nail matrix; growth of nails is 1 mm per week on average. The lunula is the crescent-shape area at the base of the nail, this is a lighter color as it mixes with the matrix cells. Also, the stratum corneum is the top part of the epidermis. The dermis is the middle layer of skin, composed of dense irregular connective tissue and areolar connective tissue such as a collagen with elastin arranged in a diffusely bundled and woven pattern. The dermis has two layers. One is the papillary layer which is the superficial layer and consists of"
"dermis, which, in addition to melanin, may contain guanine or carotenoid pigments. Many species, such as chameleons and flounders may be able to change the colour of their skin by adjusting the relative size of their chromatophores. ""See also: amphibians"" Amphibians possess two types of glands, mucous and granular (serous). Both of these glands are part of the integument and thus considered cutaneous. Mucous and granular glands are both divided into three different sections which all connect to structure the gland as a whole. The three individual parts of the gland are the duct, the intercalary region, and lastly the"
"through the epidermis, glands, or hair follicles. Sweat glands and hair follicles make up about 0.1 to 1.0 percent of the total skin surface. Though small amounts of chemicals may enter the body rapidly through the glands or hair follicles, they are primarily absorbed through the epidermis. Chemicals must pass through the seven cell layers of epidermis before entering the dermis where they can enter the blood stream or lymph and circulate to other areas of the body. Toxins and toxicants can move through the layers by passive diffusion. The stratum corneum is the outermost layer of the epidermis and"
"Epidermis The epidermis is the outermost of the three layers that make up the skin, the inner layers being the dermis and hypodermis. The epidermis layer provides a barrier to infection from environmental pathogens and regulates the amount of water released from the body into the atmosphere through transepidermal water loss. The epidermis is composed of multiple layers of flattened cells that overlie a base layer (stratum basale) composed of columnar cells arranged perpendicularly. The rows of cells develop from stem cells in the basal layer. Cellular mechanisms for regulating water and sodium levels (ENaCs) are found in all layers"
"Dartos The dartos fascia or simply dartos is a layer of connective tissue found in the penile shaft, foreskin, and scrotum. The penile portion is referred to as the superficial fascia of penis or the subcutaneous tissue of penis, while the scrotal part is the dartos proper. In addition to being continuous with itself between the scrotum and the penis, it is also continuous with Colles fascia of the perineum and Scarpa's fascia of the abdomen. It lies just below the skin, which places it just superficial to the external spermatic fascia in the scrotum and to Buck's fascia in"
"at the tip of the foreskin. The whorl of fibers acts as a sphincter in infants, which opens to allow the passage of urine, but closes to protect the glans penis from foreign matter and contaminants. The dartos fascia is sensitive to temperature and expands and contracts with temperature changes. The dartos fascia is only loosely connected with the underlying tissue so it provides the skin mobility and elasticity of the penile skin. The College of Physicians and Surgeons of British Columbia has written that the foreskin is ""composed of an outer skin and an inner mucosa that is rich"
"Skin Skin is the soft outer tissue covering of vertebrates. Other animal coverings, such as the arthropod exoskeleton, have different developmental origin, structure and chemical composition. The adjective cutaneous means ""of the skin"" (from Latin ""cutis"", skin). In mammals, the skin is an organ of the integumentary system made up of multiple layers of ectodermal tissue, and guards the underlying muscles, bones, ligaments and internal organs. Skin of a different nature exists in amphibians, reptiles, and birds. All mammals have some hair on their skin, even marine mammals like whales, dolphins, and porpoises which appear to be hairless. The skin"
"keratinocytes, melanocytes, Langerhans cells, and Merkel cells. Of these, keratinocytes are the major component, constituting roughly 95% of the epidermis. This stratified squamous epithelium is maintained by cell division within the stratum basale, in which differentiating cells slowly displace outwards through the stratum spinosum to the stratum corneum, where cells are continually shed from the surface. In normal skin, the rate of production equals the rate of loss; about two weeks are needed for a cell to migrate from the basal cell layer to the top of the granular cell layer, and an additional two weeks to cross the stratum"
"collagen (collagen VII). DEB-causing mutations can be either autosomal dominant or autosomal recessive. Epidermis bullosa pruriginosa and Albopapuloid epidermolysis bullosa (Pasini's disease) are rare subtypes of this disease. The human skin consists of two layers: an outermost layer called the epidermis and a layer underneath called the dermis. In individuals with healthy skin, there are protein anchors between these two layers that prevent them from moving independently from one another (shearing). In people born with EB, the two skin layers lack the protein anchors that hold them together, resulting in extremely fragile skin—even minor mechanical friction (like rubbing or pressure)"
"Hair Hair is a protein filament that grows from follicles found in the dermis. Hair is one of the defining characteristics of mammals. The human body, apart from areas of glabrous skin, is covered in follicles which produce thick terminal and fine vellus hair. Most common interest in hair is focused on hair growth, hair types, and hair care, but hair is also an important biomaterial primarily composed of protein, notably alpha-keratin. Attitudes towards different hair, such as hairstyles and hair removal, vary widely across different cultures and historical periods, but it is often used to indicate a person's personal"
"Dermatophyte Dermatophytes (from Greek "" derma"" ""skin"" ( ""dermatos"") and ""phyton"" ""plant"") are a common label for a group of three types of fungus that commonly causes skin disease in animals and humans. These anamorphic (asexual or imperfect fungi) mold genera are: ""Microsporum"", ""Epidermophyton"" and ""Trichophyton"". There are about 40 species in these three genera. Species capable of reproducing sexually belong in the teleomorphic genus Arthroderma, of the Ascomycota (see Teleomorph, anamorph and holomorph for more information on this type of fungal life cycle). Dermatophytes cause infections of the skin, hair, and nails, obtaining nutrients from keratinized material. The organisms"
"layers of the skin. It forms a protective barrier over the body's surface, responsible for keeping water in the body and preventing pathogens from entering, and is a stratified squamous epithelium, composed of proliferating basal and differentiated suprabasal keratinocytes. Keratinocytes are the major cells, constituting 95% of the epidermis, while Merkel cells, melanocytes and Langerhans cells are also present. The epidermis can be further subdivided into the following ""strata"" or layers (beginning with the outermost layer): Keratinocytes in the stratum basale proliferate through mitosis and the daughter cells move up the strata changing shape and composition as they undergo multiple"
"cutaneous abnormalities, infection, and neurological deficits. Congenital dermal sinus is a tract from the surface layer of the skin, through the deeper tissues into the cranial or spinal cavity. The skin findings of this tract can include: The stratified squamous epithelium of the congenital dermal sinus tract can extend to the spinal fascia of the dura mater or all the way to the spinal cord. Thus, the congenital dermal sinus forms a point of entry for infection, this can allow for the formation of an abscess. Infection can then travel up the spinal cord to result in meningitis, which can"
"are connected by vertical communicating vessels. The function of blood vessels within the dermis is fourfold: to supply nutrition, to regulate temperature, to modulate inflammation, and to participate in wound healing. The subcutaneous tissue is a layer of fat between the dermis and underlying fascia. This tissue may be further divided into two components, the actual fatty layer, or panniculus adiposus, and a deeper vestigial layer of muscle, the panniculus carnosus. The main cellular component of this tissue is the adipocyte, or fat cell. The structure of this tissue is composed of septal (i.e. linear strands) and lobular compartments, which"
"Within the latter type, hairs in structures called pilosebaceous units have a hair follicle, sebaceous gland, and associated arrector pili muscle. In the embryo, the epidermis, hair, and glands are from the ectoderm, which is chemically influenced by the underlying mesoderm that forms the dermis and subcutaneous tissues. The epidermis is the most superficial layer of skin, a squamous epithelium with several strata: the stratum corneum, stratum lucidum, stratum granulosum, stratum spinosum, and stratum basale. Nourishment is provided to these layers via diffusion from the dermis, since the epidermis is without direct blood supply. The epidermis contains four cell types:"
"body regions, their numbers remain the same in individual body regions in all human beings. In white and Asian skin the melanosomes are packed in ""aggregates"", but in black skin they are larger and distributed more evenly. The number of melanosomes in the keratinocytes increases with UV radiation exposure, while their distribution remain largely unaffected. Laboratory culture of keratinocytes to form a 3D structure (artificial skin) recapitulating most of the properties of the epidermis is routinely used as a tool for drug development and testing. Epidermis The epidermis is the outermost of the three layers that make up the skin,"
"Dermatitis Dermatitis, also known as eczema, is a group of diseases that results in inflammation of the skin. These diseases are characterized by itchiness, red skin and a rash. In cases of short duration, there may be small blisters, while in long-term cases the skin may become thickened. The area of skin involved can vary from small to the entire body. Dermatitis is a group of skin conditions that includes atopic dermatitis, allergic contact dermatitis, irritant contact dermatitis and stasis dermatitis. The exact cause of dermatitis is often unclear. Cases may involve a combination of irritation, allergy and poor venous"
"lead to abnormal detachment of squames as visible clusters. Xerosis is common, especially in elderly individuals which may be due to decreased quantity of free amino acids, a constituent of natural moisturizing factor. Consequently, many moisturizers in the markets incorporate the components of the natural moisturizing factor as well as keratin and elastin. Corneocytes are part of the stratum corneum of the epidermis and contribute the barrier function of the skin. Corneocyte Corneocytes are terminally differentiated keratinocytes and compose most if not all of the stratum corneum, the outermost part of the epidermis. They are regularly replaced through desquamation and"
"primarily made up of adipose tissue. Substantial collagen bundles anchor the dermis to the hypodermis in a way that permits most areas of the skin to move freely over the deeper tissue layers. The epidermis is the top layer of skin made up of epithelial cells. It does not contain blood vessels. Its main functions are protection, absorption of nutrients, and homeostasis. In structure, it consists of a keratinized stratified squamous epithelium ; four types of cells: keratinocytes, melanocytes, Merkel cells, and Langerhans cells. The major cell of the epidermis is the keratinocyte, which produces keratin. Keratin is a fibrous"
"has launched the Human Microbiome Project to characterize the human microbiota which includes that on the skin and the role of this microbiome in health and disease. Microorganisms like ""Staphylococcus epidermidis"" colonize the skin surface. The density of skin flora depends on region of the skin. The disinfected skin surface gets recolonized from bacteria residing in the deeper areas of the hair follicle, gut and urogenital openings. Diseases of the skin include skin infections and skin neoplasms (including skin cancer). Dermatology is the branch of medicine that deals with conditions of the skin. The skin supports its own ecosystems of"
"[[dermis]] and the [[hypodermis]]. The epidermis is typically 10 to 30 cells thick; its main function is to provide a waterproof layer. Its outermost cells are constantly lost; its bottommost cells are constantly dividing and pushing upward. The middle layer, the dermis, is 15 to 40 times thicker than the epidermis. The dermis is made up of many components, such as bony structures and blood vessels. The hypodermis is made up of [[adipose tissue]], which stores lipids and provides cushioning and insulation. The thickness of this layer varies widely from species to species; [[marine mammal]]s require a thick hypodermis ([[blubber]])"