Dermis: A layer of vascularized connective tissue underneath the EPIDERMIS. The surface of the dermis contains innervated papillae. Embedded in or beneath the dermis are SWEAT GLANDS; HAIR FOLLICLES; and SEBACEOUS GLANDS.Skin: The outer covering of the body that protects it from the environment. It is composed of the DERMIS and the EPIDERMIS.Acellular Dermis: Remaining tissue from normal DERMIS tissue after the cells are removed.Epidermis: The external, nonvascular layer of the skin. It is made up, from within outward, of five layers of EPITHELIUM: (1) basal layer (stratum basale epidermidis); (2) spinous layer (stratum spinosum epidermidis); (3) granular layer (stratum granulosum epidermidis); (4) clear layer (stratum lucidum epidermidis); and (5) horny layer (stratum corneum epidermidis).Feathers: Flat keratinous structures found on the skin surface of birds. Feathers are made partly of a hollow shaft fringed with barbs. They constitute the plumage.Skin, Artificial: Synthetic material used for the treatment of burns and other conditions involving large-scale loss of skin. It often consists of an outer (epidermal) layer of silicone and an inner (dermal) layer of collagen and chondroitin 6-sulfate. The dermal layer elicits new growth and vascular invasion and the outer layer is later removed and replaced by a graft.Skin Aging: The process of aging due to changes in the structure and elasticity of the skin over time. It may be a part of physiological aging or it may be due to the effects of ultraviolet radiation, usually through exposure to sunlight.Skin DiseasesDermatitis: Any inflammation of the skin.Keratinocytes: Epidermal cells which synthesize keratin and undergo characteristic changes as they move upward from the basal layers of the epidermis to the cornified (horny) layer of the skin. Successive stages of differentiation of the keratinocytes forming the epidermal layers are basal cell, spinous or prickle cell, and the granular cell.Skin Physiological Phenomena: The functions of the skin in the human and animal body. It includes the pigmentation of the skin.Langerhans Cells: Recirculating, dendritic, antigen-presenting cells containing characteristic racket-shaped granules (Birbeck granules). They are found principally in the stratum spinosum of the EPIDERMIS and are rich in Class II MAJOR HISTOCOMPATIBILITY COMPLEX molecules. Langerhans cells were the first dendritic cell to be described and have been a model of study for other dendritic cells (DCs), especially other migrating DCs such as dermal DCs and INTERSTITIAL DENDRITIC CELLS.Skin Neoplasms: Tumors or cancer of the SKIN.Hair Follicle: A tube-like invagination of the EPIDERMIS from which the hair shaft develops and into which SEBACEOUS GLANDS open. The hair follicle is lined by a cellular inner and outer root sheath of epidermal origin and is invested with a fibrous sheath derived from the dermis. (Stedman, 26th ed) Follicles of very long hairs extend into the subcutaneous layer of tissue under the SKIN.Cicatrix, Hypertrophic: An elevated scar, resembling a KELOID, but which does not spread into surrounding tissues. It is formed by enlargement and overgrowth of cicatricial tissue and regresses spontaneously.Skin Transplantation: The grafting of skin in humans or animals from one site to another to replace a lost portion of the body surface skin.Wound Healing: Restoration of integrity to traumatized tissue.Keloid: A sharply elevated, irregularly shaped, progressively enlarging scar resulting from formation of excessive amounts of collagen in the dermis during connective tissue repair. It is differentiated from a hypertrophic scar (CICATRIX, HYPERTROPHIC) in that the former does not spread to surrounding tissues.Collagen: A polypeptide substance comprising about one third of the total protein in mammalian organisms. It is the main constituent of SKIN; CONNECTIVE TISSUE; and the organic substance of bones (BONE AND BONES) and teeth (TOOTH).Mice, Hairless: Mutant strains of mice that produce little or no hair.Sea Cucumbers: A class of Echinodermata characterized by long, slender bodies.Melanocytes: Mammalian pigment cells that produce MELANINS, pigments found mainly in the EPIDERMIS, but also in the eyes and the hair, by a process called melanogenesis. Coloration can be altered by the number of melanocytes or the amount of pigment produced and stored in the organelles called MELANOSOMES. The large non-mammalian melanin-containing cells are called MELANOPHORES.Dermatologic Surgical Procedures: Operative procedures performed on the SKIN.Skin Absorption: Uptake of substances through the SKIN.Psoriasis: A common genetically determined, chronic, inflammatory skin disease characterized by rounded erythematous, dry, scaling patches. The lesions have a predilection for nails, scalp, genitalia, extensor surfaces, and the lumbosacral region. Accelerated epidermopoiesis is considered to be the fundamental pathologic feature in psoriasis.Fibroblasts: Connective tissue cells which secrete an extracellular matrix rich in collagen and other macromolecules.Skin Abnormalities: Congenital structural abnormalities of the skin.Injections, Intradermal: The forcing into the skin of liquid medication, nutrient, or other fluid through a hollow needle, piercing the top skin layer.Ear, External: The outer part of the hearing system of the body. It includes the shell-like EAR AURICLE which collects sound, and the EXTERNAL EAR CANAL, the TYMPANIC MEMBRANE, and the EXTERNAL EAR CARTILAGES.Elastic Tissue: Connective tissue comprised chiefly of elastic fibers. Elastic fibers have two components: ELASTIN and MICROFIBRILS.Immunohistochemistry: Histochemical localization of immunoreactive substances using labeled antibodies as reagents.Somites: Paired, segmented masses of MESENCHYME located on either side of the developing spinal cord (neural tube). Somites derive from PARAXIAL MESODERM and continue to increase in number during ORGANOGENESIS. Somites give rise to SKELETON (sclerotome); MUSCLES (myotome); and DERMIS (dermatome).Sebaceous Glands: Small, sacculated organs found within the DERMIS. Each gland has a single duct that emerges from a cluster of oval alveoli. Each alveolus consists of a transparent BASEMENT MEMBRANE enclosing epithelial cells. The ducts from most sebaceous glands open into a HAIR FOLLICLE, but some open on the general surface of the SKIN. Sebaceous glands secrete SEBUM.Connective Tissue: Tissue that supports and binds other tissues. It consists of CONNECTIVE TISSUE CELLS embedded in a large amount of EXTRACELLULAR MATRIX.Rats, Hairless: Mutant strains of rats that produce little or no hair. Several different homozygous recessive mutations can cause hairlessness in rats including rnu/rnu (Rowett nude), fz/fz (fuzzy), shn/shn (shorn), and nznu/nznu (New Zealand nude). Note that while NUDE RATS are often hairless, they are most characteristically athymic.Hyperpigmentation: Excessive pigmentation of the skin, usually as a result of increased epidermal or dermal melanin pigmentation, hypermelanosis. Hyperpigmentation can be localized or generalized. The condition may arise from exposure to light, chemicals or other substances, or from a primary metabolic imbalance.Occlusive Dressings: Material, usually gauze or absorbent cotton, used to cover and protect wounds, to seal them from contact with air or bacteria. (From Dorland, 27th ed)Chick Embryo: The developmental entity of a fertilized chicken egg (ZYGOTE). The developmental process begins about 24 h before the egg is laid at the BLASTODISC, a small whitish spot on the surface of the EGG YOLK. After 21 days of incubation, the embryo is fully developed before hatching.Blister: Visible accumulations of fluid within or beneath the epidermis.Melanosis: Disorders of increased melanin pigmentation that develop without preceding inflammatory disease.Quail: Common name for two distinct groups of BIRDS in the order GALLIFORMES: the New World or American quails of the family Odontophoridae and the Old World quails in the genus COTURNIX, family Phasianidae.Artificial Organs: Devices intended to replace non-functioning organs. They may be temporary or permanent. Since they are intended always to function as the natural organs they are replacing, they should be differentiated from PROSTHESES AND IMPLANTS and specific types of prostheses which, though also replacements for body parts, are frequently cosmetic (EYE, ARTIFICIAL) as well as functional (ARTIFICIAL LIMBS).Holothuria: A genus of large SEA CUCUMBERS in the family Holothuriidae possessing thick body walls, a warty body surface, and microscopic ossicles.Skin Pigmentation: Coloration of the skin.Biopsy: Removal and pathologic examination of specimens in the form of small pieces of tissue from the living body.Erythema: Redness of the skin produced by congestion of the capillaries. This condition may result from a variety of causes.Administration, Cutaneous: The application of suitable drug dosage forms to the skin for either local or systemic effects.Microfibrils: Components of the extracellular matrix consisting primarily of fibrillin. They are essential for the integrity of elastic fibers.Hair: A filament-like structure consisting of a shaft which projects to the surface of the SKIN from a root which is softer than the shaft and lodges in the cavity of a HAIR FOLLICLE. It is found on most surfaces of the body.Mucinoses: Mucoid states characterized by the elevated deposition and accumulation of mucin (mucopolysaccharides) in dermal tissue. The fibroblasts are responsible for the production of acid mucopolysaccharides (GLYCOSAMINOGLYCANS) in the ground substance of the connective tissue system. When fibroblasts produce abnormally large quantities of mucopolysaccharides as hyaluronic acid, chondroitin sulfate, or heparin, they accumulate in large amounts in the dermis.Subcutaneous Tissue: Loose connective tissue lying under the DERMIS, which binds SKIN loosely to subjacent tissues. It may contain a pad of ADIPOCYTES, which vary in number according to the area of the body and vary in size according to the nutritional state.Ultraviolet Rays: That portion of the electromagnetic spectrum immediately below the visible range and extending into the x-ray frequencies. The longer wavelengths (near-UV or biotic or vital rays) are necessary for the endogenous synthesis of vitamin D and are also called antirachitic rays; the shorter, ionizing wavelengths (far-UV or abiotic or extravital rays) are viricidal, bactericidal, mutagenic, and carcinogenic and are used as disinfectants.Facial DermatosesEar: The hearing and equilibrium system of the body. It consists of three parts: the EXTERNAL EAR, the MIDDLE EAR, and the INNER EAR. Sound waves are transmitted through this organ where vibration is transduced to nerve signals that pass through the ACOUSTIC NERVE to the CENTRAL NERVOUS SYSTEM. The inner ear also contains the vestibular organ that maintains equilibrium by transducing signals to the VESTIBULAR NERVE.Granulation Tissue: A vascular connective tissue formed on the surface of a healing wound, ulcer, or inflamed tissue. It consists of new capillaries and an infiltrate containing lymphoid cells, macrophages, and plasma cells.Microscopy, Electron: Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.Facial NeoplasmsScleroderma, Localized: A term used to describe a variety of localized asymmetrical SKIN thickening that is similar to those of SYSTEMIC SCLERODERMA but without the disease features in the multiple internal organs and BLOOD VESSELS. Lesions may be characterized as patches or plaques (morphea), bands (linear), or nodules.Eye Evisceration: The surgical removal of the inner contents of the eye, leaving the sclera intact. It should be differentiated from ORBIT EVISCERATION which removes the entire contents of the orbit, including eyeball, blood vessels, muscles, fat, nerve supply, and periosteum.Basement Membrane: A darkly stained mat-like EXTRACELLULAR MATRIX (ECM) that separates cell layers, such as EPITHELIUM from ENDOTHELIUM or a layer of CONNECTIVE TISSUE. The ECM layer that supports an overlying EPITHELIUM or ENDOTHELIUM is called basal lamina. Basement membrane (BM) can be formed by the fusion of either two adjacent basal laminae or a basal lamina with an adjacent reticular lamina of connective tissue. BM, composed mainly of TYPE IV COLLAGEN; glycoprotein LAMININ; and PROTEOGLYCAN, provides barriers as well as channels between interacting cell layers.Cicatrix: The fibrous tissue that replaces normal tissue during the process of WOUND HEALING.Leg Dermatoses: A nonspecific term used to denote any cutaneous lesion or group of lesions, or eruptions of any type on the leg. (From Stedman, 25th ed)Skin Diseases, Parasitic: Skin diseases caused by ARTHROPODS; HELMINTHS; or other parasites.Keratosis: Any horny growth such as a wart or callus.Skin UlcerVersicans: HYALURONAN-containing proteoglycans found in the EXTRACELLULAR MATRIX of a variety of tissues and organs. Several versican isoforms exist due to multiple ALTERNATIVE SPLICING of the versican MESSENGER RNA.Nevus, Pigmented: A nevus containing melanin. The term is usually restricted to nevocytic nevi (round or oval collections of melanin-containing nevus cells occurring at the dermoepidermal junction of the skin or in the dermis proper) or moles, but may be applied to other pigmented nevi.Eye, Artificial: A ready-made or custom-made prosthesis of glass or plastic shaped and colored to resemble the anterior portion of a normal eye and used for cosmetic reasons. It is attached to the anterior portion of an orbital implant (ORBITAL IMPLANTS) which is placed in the socket of an enucleated or eviscerated eye. (From Dorland, 28th ed)Dermatitis, Atopic: A chronic inflammatory genetically determined disease of the skin marked by increased ability to form reagin (IgE), with increased susceptibility to allergic rhinitis and asthma, and hereditary disposition to a lowered threshold for pruritus. It is manifested by lichenification, excoriation, and crusting, mainly on the flexural surfaces of the elbow and knee. In infants it is known as infantile eczema.Mycosis Fungoides: A chronic, malignant T-cell lymphoma of the skin. In the late stages, the LYMPH NODES and viscera are affected.Lichen Sclerosus et Atrophicus: A chronic inflammatory mucocutaneous disease usually affecting the female genitalia (VULVAR LICHEN SCLEROSUS) and BALANITIS XEROTICA OBLITERANS in males. It is also called white spot disease and Csillag's disease.Hoof and Claw: Highly keratinized processes that are sharp and curved, or flat with pointed margins. They are found especially at the end of the limbs in certain animals.Ehlers-Danlos Syndrome: A heterogeneous group of autosomally inherited COLLAGEN DISEASES caused by defects in the synthesis or structure of FIBRILLAR COLLAGEN. There are numerous subtypes: classical, hypermobility, vascular, and others. Common clinical features include hyperextensible skin and joints, skin fragility and reduced wound healing capability.Dermatitis, Allergic Contact: A contact dermatitis due to allergic sensitization to various substances. These substances subsequently produce inflammatory reactions in the skin of those who have acquired hypersensitivity to them as a result of prior exposure.Dermatitis, Contact: A type of acute or chronic skin reaction in which sensitivity is manifested by reactivity to materials or substances coming in contact with the skin. It may involve allergic or non-allergic mechanisms.Histological Techniques: Methods of preparing tissue for examination and study of the origin, structure, function, or pathology.Cells, Cultured: Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.Pseudoxanthoma Elasticum: An inherited disorder of connective tissue with extensive degeneration and calcification of ELASTIC TISSUE primarily in the skin, eye, and vasculature. At least two forms exist, autosomal recessive and autosomal dominant. This disorder is caused by mutations of one of the ATP-BINDING CASSETTE TRANSPORTERS. Patients are predisposed to MYOCARDIAL INFARCTION and GASTROINTESTINAL HEMORRHAGE.Morphogenesis: The development of anatomical structures to create the form of a single- or multi-cell organism. Morphogenesis provides form changes of a part, parts, or the whole organism.Administration, Topical: The application of drug preparations to the surfaces of the body, especially the skin (ADMINISTRATION, CUTANEOUS) or mucous membranes. This method of treatment is used to avoid systemic side effects when high doses are required at a localized area or as an alternative systemic administration route, to avoid hepatic processing for example.Silicone Elastomers: Polymers of silicone that are formed by crosslinking and treatment with amorphous silica to increase strength. They have properties similar to vulcanized natural rubber, in that they stretch under tension, retract rapidly, and fully recover to their original dimensions upon release. They are used in the encapsulation of surgical membranes and implants.Skin Diseases, Papulosquamous: A group of dermatoses with distinct morphologic features. The primary lesion is most commonly a papule, usually erythematous, with a variable degree of scaling on the surface. Plaques form through the coalescing of primary lesions.Decorin: A small leucine-rich proteoglycan that interacts with FIBRILLAR COLLAGENS and modifies the EXTRACELLULAR MATRIX structure of CONNECTIVE TISSUE. Decorin has also been shown to play additional roles in the regulation of cellular responses to GROWTH FACTORS. The protein contains a single glycosaminoglycan chain and is similar in structure to BIGLYCAN.Extracellular Matrix Proteins: Macromolecular organic compounds that contain carbon, hydrogen, oxygen, nitrogen, and usually, sulfur. These macromolecules (proteins) form an intricate meshwork in which cells are embedded to construct tissues. Variations in the relative types of macromolecules and their organization determine the type of extracellular matrix, each adapted to the functional requirements of the tissue. The two main classes of macromolecules that form the extracellular matrix are: glycosaminoglycans, usually linked to proteins (proteoglycans), and fibrous proteins (e.g., COLLAGEN; ELASTIN; FIBRONECTINS; and LAMININ).Mice, Inbred C57BLScleredema Adultorum: A diffuse, non-pitting induration of the skin of unknown etiology that occurs most commonly in association with diabetes mellitus, predominantly in females. It typically begins on the face or head and spreads to other areas of the body, sometimes involving noncutaneous tissues. Often it is preceded by any of various infections, notably staphylococcal infections. The condition resolves spontaneously, usually within two years of onset. (From Dorland, 27th ed)Sweat Glands: Sweat-producing structures that are embedded in the DERMIS. Each gland consists of a single tube, a coiled body, and a superficial duct.Scalp: The outer covering of the calvaria. It is composed of several layers: SKIN; subcutaneous connective tissue; the occipitofrontal muscle which includes the tendinous galea aponeurotica; loose connective tissue; and the pericranium (the PERIOSTEUM of the SKULL).Skin Diseases, Genetic: Diseases of the skin with a genetic component, usually the result of various inborn errors of metabolism.Burns: Injuries to tissues caused by contact with heat, steam, chemicals (BURNS, CHEMICAL), electricity (BURNS, ELECTRIC), or the like.Cell Movement: The movement of cells from one location to another. Distinguish from CYTOKINESIS which is the process of dividing the CYTOPLASM of a cell.Keratins: A class of fibrous proteins or scleroproteins that represents the principal constituent of EPIDERMIS; HAIR; NAILS; horny tissues, and the organic matrix of tooth ENAMEL. Two major conformational groups have been characterized, alpha-keratin, whose peptide backbone forms a coiled-coil alpha helical structure consisting of TYPE I KERATIN and a TYPE II KERATIN, and beta-keratin, whose backbone forms a zigzag or pleated sheet structure. alpha-Keratins have been classified into at least 20 subtypes. In addition multiple isoforms of subtypes have been found which may be due to GENE DUPLICATION.Asepsis: The prevention of access by infecting organisms to the locus of potential infection.Extracellular Matrix: A meshwork-like substance found within the extracellular space and in association with the basement membrane of the cell surface. It promotes cellular proliferation and provides a supporting structure to which cells or cell lysates in culture dishes adhere.Mesoderm: The middle germ layer of an embryo derived from three paired mesenchymal aggregates along the neural tube.Hyaluronic Acid: A natural high-viscosity mucopolysaccharide with alternating beta (1-3) glucuronide and beta (1-4) glucosaminidic bonds. It is found in the UMBILICAL CORD, in VITREOUS BODY and in SYNOVIAL FLUID. A high urinary level is found in PROGERIA.Back: The rear surface of an upright primate from the shoulders to the hip, or the dorsal surface of tetrapods.Keratolytic Agents: Agents that soften, separate, and cause desquamation of the cornified epithelium or horny layer of skin. They are used to expose mycelia of infecting fungi or to treat corns, warts, and certain other skin diseases.In Situ Hybridization: A technique that localizes specific nucleic acid sequences within intact chromosomes, eukaryotic cells, or bacterial cells through the use of specific nucleic acid-labeled probes.Angiokeratoma: A vascular, horny neoplasm of the skin characterized by TELANGIECTASIS and secondary epithelial changes including acanthosis and hyperkeratosis.Scleroderma, Systemic: A chronic multi-system disorder of CONNECTIVE TISSUE. It is characterized by SCLEROSIS in the SKIN, the LUNGS, the HEART, the GASTROINTESTINAL TRACT, the KIDNEYS, and the MUSCULOSKELETAL SYSTEM. Other important features include diseased small BLOOD VESSELS and AUTOANTIBODIES. The disorder is named for its most prominent feature (hard skin), and classified into subsets by the extent of skin thickening: LIMITED SCLERODERMA and DIFFUSE SCLERODERMA.Pigmentation DisordersLeishmaniasis, Cutaneous: An endemic disease that is characterized by the development of single or multiple localized lesions on exposed areas of skin that typically ulcerate. The disease has been divided into Old and New World forms. Old World leishmaniasis is separated into three distinct types according to epidemiology and clinical manifestations and is caused by species of the L. tropica and L. aethiopica complexes as well as by species of the L. major genus. New World leishmaniasis, also called American leishmaniasis, occurs in South and Central America and is caused by species of the L. mexicana or L. braziliensis complexes.Antigens, CD1: Glycoproteins expressed on cortical thymocytes and on some dendritic cells and B-cells. Their structure is similar to that of MHC Class I and their function has been postulated as similar also. CD1 antigens are highly specific markers for human LANGERHANS CELLS.Pemphigoid, Bullous: A chronic and relatively benign subepidermal blistering disease usually of the elderly and without histopathologic acantholysis.Dermabrasion: The mechanical planing of the SKIN with sand paper, emery paper, or wire brushes, to promote reepithelialization and smoothing of skin disfigured by ACNE scars or dermal NEVI.

Interferon-alpha does not improve outcome at one year in patients with diffuse cutaneous scleroderma: results of a randomized, double-blind, placebo-controlled trial. (1/1009)

OBJECTIVE: To determine whether interferon-alpha (IFNalpha) reduces the severity of skin involvement in early (<3 years) diffuse scleroderma. METHODS: In a randomized, placebo-controlled, double-blind trial, 35 patients with early scleroderma received subcutaneous injections of either IFNalpha (13.5 x 10(6) units per week in divided doses) or indistinguishable placebo. Outcomes assessed were the modified Rodnan skin score, as determined by a single observer at baseline, 6 months, and 12 months, as well as data on renal, cardiac, and lung function. Pre- and posttreatment skin biopsy samples were analyzed and blood was obtained for assessment of procollagen peptide levels. RESULTS: There were 11 withdrawals from the IFNalpha group and 3 from the placebo group due to either toxicity, lack of efficacy, or death. In the intent-to-treat analysis, there was a greater improvement in the skin score in the placebo group between 0 and 12 months (mean change IFNalpha -4.7 versus placebo -7.5; P = 0.36). There was also a greater deterioration in lung function in patients receiving active therapy, as assessed by either the forced vital capacity (mean change IFNalpha -8.2 versus placebo +1.3; P = 0.01) or the diffusing capacity for carbon monoxide (mean change IFNalpha -9.3 versus placebo +4.7; P = 0.002). Skin biopsy showed no significant decrease in collagen synthesis in the IFNalpha group, and no significant differences in the levels of procollagen peptides were seen between the 2 groups. CONCLUSION: This study suggests that IFNalpha is of no value in the treatment of scleroderma, and that it may in fact be deleterious.  (+info)

Skin morphology and its role in thermoregulation in mole-rats, Heterocephalus glaber and Cryptomys hottentotus. (2/1009)

The skin structure of 2 Bathyergid rodents, the naked mole-rat (Heterocephalus glaber) and the common mole-rat (Cryptomys hottentotus) is compared, to investigate whether thermoregulatory differences may be attributed to different skin features. Histological and ultrastructural studies of the dorsal skin of these closely related species show morphological and structural similarities but differences in the degree of skin folding, thickness of the integument and dermal infrastructure were evident. The skin of the common mole-rat conforms with expected morphological/histological arrangements that are commonly found in mammalian skin. Many features of the skin of the naked mole-rat, such as the lack of an insulating layer and the loosely folded morphological arrangement contribute to poikilothermic responses to changing temperatures of this mammal. Further evidence for poikilothermy in the naked mole-rat is indicated by the presence of pigment containing cells in the dermis, rather than the epidermis, as commonly occurs in homeotherms. Lack of fur is compensated by a thicker epidermal layer and a marked reduction in sweat glands. Differences in skin morphology thus contribute substantially to the different thermoregulatory abilities of the 2 Bathyergids. The skin morphology is related to the poor thermoinsulatory ability of the animals while simultaneously facilitating heat transfer from the environment to the animal by thigmothermy and/or other behavioural means.  (+info)

Multiple mechanisms contribute to the avoidance of avian epidermis by sensory axons. (3/1009)

In birds, sensory innervation of skin is restricted to dermis, with few axons penetrating into the epidermis. This pattern of innervation is maintained in vitro, where sensory neurites avoid explants of epidermis but grow readily on dermis. We have used this coculture paradigm to investigate the mechanisms that impede innervation of avian epidermis. The lack of epidermal innervation in birds has been attributed to diffusible chondroitin sulfate proteoglycans (CSPGs) secreted by the epidermis, although direct experimental evidence is weak. We found that elimination of CSPG function with either chondroitinase or neutralizing antibodies did not promote growth of DRG neurites onto epidermis in vitro, indicating that CSPGs alone are not responsible for preventing epidermal innervation. Moreover, the failure of sensory neurites to invade epidermis is not due exclusively to soluble chemorepulsive factors, since sensory neurites also avoid dead epidermis. This inhibition can be overridden, however, by coating epidermis with the growth-promoting molecule laminin, but only if the tissue is killed first. Epidermal innervation of laminin-coated epidermis is even more robust when CSPGs are also eliminated. Thus, the absence of growth-promoting or permissive molecules, such as laminin, may contribute to the failure of sensory neurites to invade avian epidermis. Together these results show that the inhibitory character of avian epidermis is complex. Cell- or matrix-associated CSPGs clearly contribute to the inhibition, but are not solely responsible.  (+info)

Fibrillin-rich microfibrils are reduced in photoaged skin. Distribution at the dermal-epidermal junction. (4/1009)

Chronic sun exposure results in photoaged skin with deep coarse wrinkles and loss of elasticity. We have examined the distribution and abundance of fibrillin-rich microfibrils, key structural components of the elastic fiber network, in photoaged and photoprotected skin. Punch biopsies taken from photoaged forearm and from photoprotected hip and upper inner arm of 16 subjects with a clinical range of photoaging were examined for fibrillin-1 and fibrillin-2 expression and microfibril distribution. In situ hybridization revealed decreased fibrillin-1 mRNA but unchanged fibrillin-2 mRNA levels in severely photoaged forearm biopsies relative to photoprotected dermal sites. An immunohistochemical approach demonstrated that microfibrils at the dermal-epidermal junction were significantly reduced in moderate to severely photoaged forearm skin. Confocal microscopy revealed that the papillary dermal microfibrillar network was truncated and depleted in photoaged skin. These studies highlight that the fibrillin-rich microfibrillar network associated with the upper dermis undergoes extensive remodeling following solar irradiation. These changes may contribute to the clinical features of photoaging, such as wrinkle formation and loss of elasticity.  (+info)

Roles for PDGF-A and sonic hedgehog in development of mesenchymal components of the hair follicle. (5/1009)

Skin appendages, such as hair, develop as a result of complex reciprocal signaling between epithelial and mesenchymal cells. These interactions are not well understood at the molecular level. Platelet-derived growth factor-A (PDGF-A) is expressed in the developing epidermis and hair follicle epithelium, and its receptor PDGF-Ralpha is expressed in associated mesenchymal structures. Here we have characterized the skin and hair phenotypes of mice carrying a null mutation in the PDGF-A gene. Postnatal PDGF-A-/- mice developed thinner dermis, misshapen hair follicles, smaller dermal papillae, abnormal dermal sheaths and thinner hair, compared with wild-type siblings. BrdU labeling showed reduced cell proliferation in the dermis and in the dermal sheaths of PDGF-A-/- skin. PDGF-A-/- skin transplantation to nude mice led to abnormal hair formation, reproducing some of the features of the skin phenotype of PDGF-A-/- mice. Taken together, expression patterns and mutant phenotypes suggest that epidermal PDGF-A has a role in stimulating the proliferation of dermal mesenchymal cells that may contribute to the formation of dermal papillae, mesenchymal sheaths and dermal fibroblasts. Finally, we show that sonic hedgehog (shh)-/- mouse embryos have disrupted formation of dermal papillae. Such embryos fail to form pre-papilla aggregates of postmitotic PDGF-Ralpha-positive cells, suggesting that shh has a critical role in the assembly of the dermal papilla.  (+info)

Propionyl-L-carnitine dilates human subcutaneous arteries through an endothelium-dependent mechanism. (6/1009)

PURPOSE: The vasoactive effects of propionyl-L-carnitine (PLC) on human arteries, including endothelial and smooth muscle cell influences, were studied. METHODS: Small (less than 200 microm) subcutaneous fat arteries (n = 19), obtained from human patients undergoing vascular surgery, were dissected and mounted in an arteriograph system that allowed measurement of lumen diameter and control of transmural pressure. To investigate the role of the endothelium, arteries were compared intact, intact and in the presence of either 0.3 mmol/L nitro-L-arginine (an inhibitor of nitric oxide synthesis) or 10 micromol/L indomethacin (an inhibitor of prostaglandin synthesis), or denuded of endothelium. After a 1-hour equilibration at a pressure of 50 mm Hg, arteries were precontracted 50% with an intermediate concentration of norepinephrine, and clinically relevant concentrations of PLC (0.1 to 100 micromol/L) were cumulatively added to the bath while the lumen diameter was continually measured. RESULTS: Intact arteries dose-dependently dilated to PLC, with the half maximal dilation occurring at 2.9 +/- 1.2 micromol/L, increasing diameter 91% +/- 5% at 100 micromol/L. In contrast, PLC had significantly less effect on deendothelialized arteries, increasing diameter only 24% +/- 11% at 100 micromol/L (P <.01 vs. intact). This indicates the endothelial dependency of this compound. Blockade of nitric oxide did not inhibit this vasodilation, with the half-maximal response occurring at 8.6 +/- 7 micromol/L, increasing diameter 85% +/- 8% at 100 micromol/L ( P >.05 vs. intact). However, this vasodilation was significantly diminished in the presence of indomethacin, which dilated arteries only 53% +/- 18% at 100 micromol/L (P <.01 vs. intact; P >.05 vs. denuded). CONCLUSION: PLC is an endothelium-dependent vasodilator, the mechanism of which is partially mediated by prostaglandin synthesis, not nitric oxide. The beneficial effects of this compound may, in part, be related to vasodilation and enhanced blood flow.  (+info)

Expression of matrix metalloproteinase-1, -2 and -3 in squamous cell carcinoma and actinic keratosis. (7/1009)

Matrix metalloproteinase (MMP) plays an important role in extracellular matrix degradation associated with cancer invasion. An expression of MMP-1 (interstitial collagenase), MMP-2 (72-kDa type IV collagenase) and MMP-3 (stromelysin-1) was investigated in squamous cell carcinoma (SCC) and its precancerous condition, actinic keratosis (AK), using in situ hybridization techniques. MMP-1 mRNA was detected in tumour cells and/or in stromal cells in all cases of SCC, four of six AKs adjacent to SCC and four of 16 AKs. MMP-2 and MMP-3 mRNAs were detected in SCC but not in AK. The expression of MMP-3 correlated to that of MMP-1 (P = 0.03) localized at the tumour mass and stroma of the invasive area, while MMP-2 mRNA was detected widely throughout the stroma independent of MMP-1 expression. Our results indicated that the expression of MMP-1, -2 and -3 showed different localization patterns, suggesting a unique role of each MMP in tumour progression. Moreover, MMP-1 expression could be an early event in the development of SCC, and AK demonstrating MMP-1 mRNA, might be in a more advanced dysplastic state, progressing to SCC.  (+info)

IP-10 inhibits epidermal growth factor-induced motility by decreasing epidermal growth factor receptor-mediated calpain activity. (8/1009)

During wound healing, fibroblasts are recruited from the surrounding tissue to accomplish repair. The requisite migration and proliferation of the fibroblasts is promoted by growth factors including those that activate the epidermal growth factor receptor (EGFR). Counterstimulatory factors in wound fluid are postulated to limit this response; among these factors is the ELR-negative CXC chemokine, interferon inducible protein-10 (IP-10). We report here that IP-10 inhibited EGF- and heparin-binding EGF-like growth factor-induced Hs68 human dermal fibroblast motility in a dose-dependent manner (to 52% and 44%, respectively, at 50 ng/ml IP-10), whereas IP-10 had no effect on either basal or EGFR-mediated mitogenesis (96 +/- 15% at 50 ng/ml). These data demonstrate for the first time a counterstimulatory effect of IP-10 on a specific induced fibroblast response, EGFR-mediated motility. To define the molecular basis of this negative transmodulation of EGFR signaling, we found that IP-10 did not adversely impact receptor or immediate postreceptor signaling as determined by tyrosyl phosphorylation of EGFR and two major downstream effectors phospholipase C-gamma and erk mitogen-activated protein kinases. Morphological studies suggested which biophysical steps may be affected by demonstrating that IP-10 treatment resulted in an elongated cell morphology reminiscent of failure to detach the uropod; in support of this, IP-10 pretreatment inhibited EGF-induced cell detachment. These data suggested that calpain activity may be involved. The cell permeant agent, calpain inhibitor I, limited EGF-induced motility and de-adhesion similarly to IP-10. IP-10 also prevented EGF- induced calpain activation (reduced by 71 +/- 7%). That this inhibition of EGF-induced calpain activity was secondary to IP-10 initiating a cAMP-protein kinase A-calpain cascade is supported by the following evidence: (a) the cell permeant analogue 8-(4-chlorophenylthio)-cAMP (CPT-cAMP) prevented EGF-induced calpain activity and motility; (b) other ELR-negative CXC chemokines, monokine induced by IFN-gamma and platelet factor 4 that also generate cAMP, inhibited EGF-induced cell migration and calpain activation; and (c) the protein kinase A inhibitor Rp-8-Br-cAMPS abrogated IP-10 inhibition of cell migration, cell detachment, and calpain activation. Our findings provide a model by which IP-10 suppresses EGF-induced cell motility by inhibiting EGF-induced detachment of the trailing edges of motile cells.  (+info)

  • Acellular dermis is a type of biomaterial derived from processing human or animal tissues to remove cells and retain portions of the extracellular matrix (ECM). (wikipedia.org)
  • With increasing frequency, surgeons are electing to use acellular dermis to assist with tissue expander or implant-based primary breast reconstruction. (medscape.com)
  • [ 3 ] Several authors have reported favorable results for procedures involving acellular dermis, and rapid early expansion has led to improved cosmetic outcomes. (medscape.com)
  • Breuing first reported the use of human acellular dermis in implant-based breast reconstruction in 2005. (medscape.com)
  • [ 4 ] Not long after, Bindingnavele reported acellular dermis-assisted tissue expander-based reconstruction. (medscape.com)
  • In 2009, Nahabedian explored the use of acellular dermis in the context of postoperative irradiation. (medscape.com)
  • [ 11 ] This study addressed the increasingly widespread sentiment that acellular dermis affected complication rates in patients receiving postoperative radiation therapy and led other authors, such as Rawlani et al, to explore these effects further. (medscape.com)
  • Any woman who is a candidate for tissue expander or implant-based reconstruction is a potential candidate for the use of acellular dermis and should be informed of the option. (medscape.com)
  • Fortiva porcine dermis is a non-crosslinked acellular porcine dermal matrix intended for use as a soft tissue patch to reinforce soft tissue where weakness exists and for the surgical repair of damaged or ruptured soft tissue membranes. (aol.com)
  • To evaluate the use, indications, and short-term outcomes for human acellular dermis. (hindawi.com)
  • We retrospectively reviewed patients having human acellular dermis placed for ventral hernia repair from January 2008 through October 2009. (hindawi.com)
  • Although followup is limited, there remains a high recurrence rate associated with the use of human acellular dermis. (hindawi.com)
  • Due to this and the paucity of data associated with many of the biologic products, we evaluated our experience with the use of human acellular dermis, one of the most commonly used biologic grafts, its indications, and outcomes for use in ventral hernia repair. (hindawi.com)
  • Following Institutional Review Board approval, we retrospectively reviewed all patients having human acellular dermis placed for repair of ventral hernias from January 1, 2008 through October 31, 2009. (hindawi.com)
  • Porcine dermis dressing versus Bisgaard therapy for leg ulcers. (bmj.com)
  • Porcine dermis. (bmj.com)
  • RTIX ) , a leading provider of orthopedic and other biologic implants, is pleased to announce the launch of its Fortiva™ porcine dermis implant at the Abdominal Wall Reconstruction (AWR) Conference in Washington, D.C., June 6-8. (aol.com)
  • RTI celebrated a milestone for Fortiva porcine dermis on May 23 when a patient in Missouri received a 10x16cm graft for an incisional hernia repair using a component separation technique. (aol.com)
  • Fortiva porcine dermis is ready-to-use, requiring no rehydration or rinsing. (aol.com)
  • Fortiva porcine dermis is sterilized through RTI's Tutoplast ® Tissue Sterilization Process, a validated chemical sterilization process that thoroughly penetrates tissue, removing antigenicity and inactivating pathogens. (aol.com)
  • The launch of Fortiva porcine dermis is a major milestone for RTI, as we now offer surgeons the most comprehensive biologic solutions in hernia repair from a provider they trust," said Brian K. Hutchison, RTI president and CEO. (aol.com)
  • Fortiva porcine dermis will be featured at the Component Separation lab station and Tutopatch bovine pericardium will be featured at the Minimally Invasive lab station. (aol.com)
  • I believe Dermira (DERM) will start improving from now on, because it looks like they hit their bottom, and they must have learned their mistakes. (fool.com)
  • Shares of Dermira, Inc. ( DERM ) hit a new high of $19.30 on Wednesday's trading before closing at $17.56. (rttnews.com)
  • Sufficient MONISTAT-DERM Cream should be applied to cover affected areas twice daily (morning and evening) in patients with tinea pedis, tinea cruris, tinea corporis, and cutaneous candidiasis, and once daily in patients with tinea versicolor. (drugs.com)
  • If MONISTAT-DERM Cream is used in intertriginous areas, it should be applied sparingly and smoothed in well to avoid maceration effects. (drugs.com)
  • Anti-wrinkle, antioxidant and antiradical, Pro-Derm Regenerating Cream has been formulated to moisturize and regenerate sensitive and couperose-prone skin. (essentialdayspa.com)
  • What conditions does Medi-Derm-L Cream treat? (webmd.com)
  • List Medi-Derm-L Cream side effects by likelihood and severity. (webmd.com)
  • What should I know regarding pregnancy, nursing and administering Medi-Derm-L Cream to children or the elderly? (webmd.com)
  • Does Medi-Derm-L Cream interact with other medications? (webmd.com)
  • Have you ever purchased Medi-Derm-L Cream? (webmd.com)
  • Rinse off cleaning foam and saturating natural cotton ball with the Clinique Acne Solutions Clarifying cream acne derm krem ulotka . (all4webs.com)
  • TAMPA Fla. - The Florida State League announced on Thursday that Tampa Tarpons DH Dermis Garcia and RHP Miguel Yajure have been named to the 2019 FSL Post-Season All-Star Team. (milb.com)
  • Pro-Derm, the premium skincare and beauty brand, recently expanded its product portfolio with the introduction of the new Pro-Derm Hydrogel. (trendhunter.com)
  • According to its varied clientele who have expressed having done countless online searches for this type of service, Bella Dermis Skin Care LLC is the only skincare studio in the Tampa Bay Area to perform Intimate Skin Bleaching and uses Safe, natural, hydroquinone-free products. (thefreedictionary.com)
  • Although identification of larvae by a biopsy is recommended for definitive diagnosis, such identification was possible in only 16 cases, including three in which the worms were easily excised after their outward migration to the dermis as a consequence of treatment with albendazole as has been recommended (6). (thefreedictionary.com)
  • That is where the e-dermis comes in, conveying information to the amputee by stimulating peripheral nerves in the arm, making the so-called phantom limb come to life. (disabled-world.com)
  • Like real skin, the e-dermis has an outer, epidermal layer and an inner, dermal layer. (hackaday.com)
  • Cyclin D1 was overexpressed primarily within the dermal-epidermal junction and/or papillary dermis in Spitz nevi, whereas cyclin D1-positive nevus cells were present throughout the lesion in most malignant melanomas. (thefreedictionary.com)
  • Dermal Revolution (DERM) is available to buy in pairs. (dermalrevolution.com)
  • 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. (wikipedia.org)
  • These protein fibers give the dermis its properties of strength, extensibility, and elasticity. (wikipedia.org)
  • Dermis serves as a cushion against stress and strain and gives elasticity to the skin. (chegg.com)
  • Vivant Skin Care Derm-A-Gel (Level I) gives your skin a revitalizing dose of Vitamin A that diminishes the appearance of wrinkles, acne and dark spots as it promotes firmness and elasticity. (secure-booker.com)
  • Inspired by human biology, the e-dermis enables its user to sense a continuous spectrum of tactile perceptions, from light touch to noxious or painful stimulus. (disabled-world.com)
  • The team created a "neuromorphic model" mimicking the touch and pain receptors of the human nervous system, allowing the e-dermis to electronically encode sensations just as the receptors in the skin would. (disabled-world.com)
  • The e-dermis technology could be used to make robotic systems more human, and it could also be used to expand or extend to astronaut gloves and space suits, Osborn says. (disabled-world.com)
  • When layered on top of prosthetic hands, this e-dermis brings back a real sense of touch through the fingertips. (disabled-world.com)
  • This is interesting and new," Osborn said, "because now we can have a prosthetic hand that is already on the market and fit it with an e-dermis that can tell the wearer whether he or she is picking up something that is round or whether it has sharp points. (disabled-world.com)
  • Speak with your skin care physician to get all the facts about Nu-Derm and to see if it might be the right system to help you finally achieve the look you want! (obagi.com)
  • Print out the personalized suggestions you get from Nu-Derm Continuum and take it to your skin care physician. (obagi.com)
  • More than 30,000 patients have turned to First Derm , a TalkSpace -esque app that pairs you with a dermatologist. (yahoo.com)
  • Derm Ink is the go-to for tattoo aftercare. (harveynichols.com)
  • But if the needle goes any deeper, fat and muscle beneath the dermis can be pierced, causing excessive bleeding and scars--signs of being gouged by a scratcher--an inept tattoo artist. (thefreedictionary.com)
  • Tattoo]] ink is injected into the dermis. (wikidoc.org)
  • T4a: The tumor has invaded the anterior orbit, anterior cranial fossa, overlying facial dermis , sphenoid sinus, or frontal sinus. (thefreedictionary.com)
  • All ECM samples originate from mammalian tissues, such as dermis, pericardium, and small intestinal submucosa (SIS). (wikipedia.org)