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Eleidin
Eleidin is clear intracellular protein which is present in the stratum lucidum of the skin. Eleidin is a transformation product of the amino acid complex keratohyalin, the lifeless matter deposited in the form of minute granules within the protoplasm of living cells. Eleidin is then converted to keratin in the stratum corneum. Eleidin can be found in the vermilion border of the lip. The lip is thinly keratinized and has a high concentration of eleidin. The red appearance of the vermillion border is due to several factors, one of which is the transparent nature of eleidin showing the color of the red blood cell Red blood cells (RBCs), also referred to as red cells, red blood corpuscles (in humans or other animals not having nucleus in red blood cells), haematids, erythroid cells or erythrocytes (from Greek ''erythros'' for "red" and ''kytos'' for "holl ...s beneath. References {{protein-stub Human proteins ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stratum Lucidum
The stratum lucidum (Latin, 'clear layer') is a thin, clear layer of dead skin cells in the epidermis named for its translucent appearance under a microscope. It is readily visible by light microscopy only in areas of thick skin, which are found on the palms of the hands and the soles of the feet. Located between the stratum granulosum and stratum corneum layers, it is composed of three to five layers of dead, flattened keratinocytes.McGrath, J.A.; Eady, R.A.; Pope, F.M. (2004). ''Rook's Textbook of Dermatology'' (Seventh Edition). Blackwell Publishing. Pages 3.8. .Tortora, Gerard; Derrickson, Bryan; Principles of Anatomy and Physiology (2009)152 John Wiley & Sons Inc, Hoboken, NJ . The keratinocytes of the stratum lucidum do not feature distinct boundaries and are filled with eleidin, an intermediate form of keratin. They are surrounded by an oily substance that is the result of the exocytosis of lamellar bodies accumulated while the keratinocytes are moving through the stratum ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skin
Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation. Other cuticle, animal coverings, such as the arthropod exoskeleton, have different cellular differentiation, developmental origin, structure and chemical composition. The adjective cutaneous means "of the skin" (from Latin ''cutis'' 'skin'). In mammals, the skin is an organ (anatomy), organ of the integumentary system made up of multiple layers of ectodermal tissue (biology), tissue and guards the underlying muscles, bones, ligaments, and internal organs. Skin of a different nature exists in amphibians, reptiles, and birds. Skin (including cutaneous and subcutaneous tissues) plays crucial roles in formation, structure, and function of extraskeletal apparatus such as horns of bovids (e.g., cattle) and rhinos, cervids' antlers, giraffids' ossicones, armadillos' osteoderm, and os penis/os clitoris. All mammals have som ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Keratohyalin
Keratohyalin is a protein structure found in cytoplasmic granules of the keratinocytes in the stratum granulosum of the epidermis. Keratohyalin granules (KHG) mainly consist of keratin, profilaggrin, loricrin and trichohyalin proteins which contribute to cornification or keratinization, the process of the formation of epidermal cornified cell envelope. During the keratinocyte differentiation, these granules maturate and expand in size, which leads to the conversion of keratin tonofilaments into a homogenous keratin matrix, an important step in cornification. Keratohyalin granules can be divided in three classes: globular KHG (found in quickly dividing epithelia, such as the oral mucose), stellate KHG (found in the slowly dividing normal epidermis) and KHG of Hassall's corpuscles or type VI epithelioreticular cells of the thymus gland. The exact purpose of the keratinization of Hassall's corpuscles remains unknown. During skin differentiation process, keratohyaline granules discha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Keratin
Keratin () is one of a family of structural fibrous proteins also known as ''scleroproteins''. Alpha-keratin (α-keratin) is a type of keratin found in vertebrates. It is the key structural material making up scales, hair, nails, feathers, horns, claws, hooves, and the outer layer of skin among vertebrates. Keratin also protects epithelial cells from damage or stress. Keratin is extremely insoluble in water and organic solvents. Keratin monomers assemble into bundles to form intermediate filaments, which are tough and form strong unmineralized epidermal appendages found in reptiles, birds, amphibians, and mammals. Excessive keratinization participate in fortification of certain tissues such as in horns of cattle and rhinos, and armadillos' osteoderm. The only other biological matter known to approximate the toughness of keratinized tissue is chitin. Keratin comes in two types, the primitive, softer forms found in all vertebrates and harder, derived forms found only amon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stratum Corneum
The stratum corneum (Latin for 'horny layer') is the outermost layer of the epidermis. The human stratum corneum comprises several levels of flattened corneocytes that are divided into two layers: the ''stratum disjunctum'' and ''stratum compactum''. The skin's protective acid mantle and lipid barrier sit on top of the stratum disjunctum. The stratum disjunctum is the uppermost and loosest layer of skin. The stratum compactum is the comparatively deeper, more compacted and more cohesive part of the stratum corneum. The corneocytes of the stratum disjunctum are larger, more rigid and more hydrophobic than that of the stratum compactum. The stratum corneum is the dead tissue that performs protective and adaptive physiological functions including mechanical shear, impact resistance, water flux and hydration regulation, microbial proliferation and invasion regulation, initiation of inflammation through cytokine activation and dendritic cell activity, and selective permeability to exc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vermilion Border
The vermilion border (sometimes spelled vermillion border), also called margin or zone, is the normally sharp demarcation between the lip and the adjacent normal skin. It represents the change in the epidermis from highly keratinized external skin to less keratinized internal skin. It has no sebaceous glands, sweat glands, or facial hair. It has a prominence on the face, creating a focus for cosmetics (it is where lipstick is sometimes applied) and is also a location for several skin diseases. Its functional properties, however, remain unknown. Structure The lips are composed wholly of soft tissue. The skin of the face is thicker than the skin overlying the lips where blood vessels are closer to the surface. As a consequence, the margin of the lips shows a transition between the thicker and thinner skin, represented by the vermilion border. It therefore has the appearance of a sharp line between the coloured edge of the lip and adjoining skin. It has been described as a pale, whit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Red Blood Cell
Red blood cells (RBCs), also referred to as red cells, red blood corpuscles (in humans or other animals not having nucleus in red blood cells), haematids, erythroid cells or erythrocytes (from Greek ''erythros'' for "red" and ''kytos'' for "hollow vessel", with ''-cyte'' translated as "cell" in modern usage), are the most common type of blood cell and the vertebrate's principal means of delivering oxygen (O2) to the body tissues—via blood flow through the circulatory system. RBCs take up oxygen in the lungs, or in fish the gills, and release it into tissues while squeezing through the body's capillaries. The cytoplasm of a red blood cell is rich in hemoglobin, an iron-containing biomolecule that can bind oxygen and is responsible for the red color of the cells and the blood. Each human red blood cell contains approximately 270 million hemoglobin molecules. The cell membrane is composed of proteins and lipids, and this structure provides properties essential for physiolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thieme Medical Publishers
Thieme Medical Publishers is a German medical and science publisher in the Thieme Publishing Group. It produces professional journals, textbooks, atlases, monographs and reference books in both German and English covering a variety of medical specialties, including neurosurgery, orthopaedics, endocrinology, urology, radiology, anatomy, chemistry, otolaryngology, ophthalmology, audiology and speech-language pathology, complementary and alternative medicine. Thieme has more than 1,000 employees and maintains offices in seven cities worldwide, including New York City, Beijing, Delhi, Stuttgart, and three other cities in Germany. History Georg Thieme Verlag was founded in 1886 in Leipzig, Germany, by Georg Thieme when he was 26 years old. Thieme remains privately held and family-owned. The company received some early success in 1896 by publishing Wilhelm Röntgen's famous picture of his wife's hand in what is still one of Thieme's and Germany's oldest journals, the ''Deutsche ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
