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.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.Ovarian Follicle: An OOCYTE-containing structure in the cortex of the OVARY. The oocyte is enclosed by a layer of GRANULOSA CELLS providing a nourishing microenvironment (FOLLICULAR FLUID). The number and size of follicles vary depending on the age and reproductive state of the female. The growing follicles are divided into five stages: primary, secondary, tertiary, Graafian, and atretic. Follicular growth and steroidogenesis depend on the presence of GONADOTROPINS.Alopecia: Absence of hair from areas where it is normally present.Follicle Stimulating Hormone: A major gonadotropin secreted by the adenohypophysis (PITUITARY GLAND, ANTERIOR). Follicle-stimulating hormone stimulates GAMETOGENESIS and the supporting cells such as the ovarian GRANULOSA CELLS, the testicular SERTOLI CELLS, and LEYDIG CELLS. FSH consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is common in the three pituitary glycoprotein hormones (TSH, LH, and FSH), but the beta subunit is unique and confers its biological specificity.Hair Diseases: Diseases affecting the orderly growth and persistence of hair.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).Hair Removal: Methods used to remove unwanted facial and body hair.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.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).Hair Color: Color of hair or fur.Hair Cells, Auditory: Sensory cells in the organ of Corti, characterized by their apical stereocilia (hair-like projections). The inner and outer hair cells, as defined by their proximity to the core of spongy bone (the modiolus), change morphologically along the COCHLEA. Towards the cochlear apex, the length of hair cell bodies and their apical STEREOCILIA increase, allowing differential responses to various frequencies of sound.Skin: The outer covering of the body that protects it from the environment. It is composed of the DERMIS and the EPIDERMIS.Keratin-15: A type I keratin found in the basal layer of the adult epidermis and in other stratified epithelia.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.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.Keratins, Hair-Specific: Keratins that are specific for hard tissues such as HAIR; NAILS; and the filiform papillae of the TONGUE.Ectodysplasins: Transmembrane proteins belonging to the tumor necrosis factor superfamily that play an essential role in the normal development of several ectodermally derived organs. Several isoforms of the ectodysplasins exist due to multiple ALTERNATIVE SPLICING of the MRNA for the protein. The isoforms ectodysplasin A1 and ectodysplasin A2 are considered biologically active and each bind distinct ECTODYSPLASIN RECEPTORS. Genetic mutations that result in loss of function of ectodysplasin result in ECTODERMAL DYSPLASIA 1, ANHIDROTIC.Ovary: The reproductive organ (GONADS) in female animals. In vertebrates, the ovary contains two functional parts: the OVARIAN FOLLICLE for the production of female germ cells (OOGENESIS); and the endocrine cells (GRANULOSA CELLS; THECA CELLS; and LUTEAL CELLS) for the production of ESTROGENS and PROGESTERONE.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.Granulosa Cells: Supporting cells for the developing female gamete in the OVARY. They are derived from the coelomic epithelial cells of the gonadal ridge. Granulosa cells form a single layer around the OOCYTE in the primordial ovarian follicle and advance to form a multilayered cumulus oophorus surrounding the OVUM in the Graafian follicle. The major functions of granulosa cells include the production of steroids and LH receptors (RECEPTORS, LH).Hair Cells, Auditory, Inner: Auditory sensory cells of organ of Corti, usually placed in one row medially to the core of spongy bone (the modiolus). Inner hair cells are in fewer numbers than the OUTER AUDITORY HAIR CELLS, and their STEREOCILIA are approximately twice as thick as those of the outer hair cells.Alopecia Areata: Loss of scalp and body hair involving microscopically inflammatory patchy areas.Ovulation: The discharge of an OVUM from a rupturing follicle in the OVARY.Follicular Fluid: The fluid surrounding the OVUM and GRANULOSA CELLS in the Graafian follicle (OVARIAN FOLLICLE). The follicular fluid contains sex steroids, glycoprotein hormones, plasma proteins, mucopolysaccharides, and enzymes.Stem Cells: Relatively undifferentiated cells that retain the ability to divide and proliferate throughout postnatal life to provide progenitor cells that can differentiate into specialized cells.Hypotrichosis: Presence of less than the normal amount of hair. (Dorland, 27th ed)Skin Abnormalities: Congenital structural abnormalities of the skin.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.Hair Dyes: Dyes used as cosmetics to change hair color either permanently or temporarily.Mice, Transgenic: Laboratory mice that have been produced from a genetically manipulated EGG or EMBRYO, MAMMALIAN.Hair Cells, Vestibular: Sensory cells in the acoustic maculae with their apical STEREOCILIA embedded in a gelatinous OTOLITHIC MEMBRANE. These hair cells are stimulated by the movement of otolithic membrane, and impulses are transmitted via the VESTIBULAR NERVE to the BRAIN STEM. Hair cells in the saccule and those in the utricle sense linear acceleration in vertical and horizontal directions, respectively.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.Hair Preparations: Hair grooming, cleansing and modifying products meant for topical application to hair, usually human. They include sprays, bleaches, dyes, conditioners, rinses, shampoos, nutrient lotions, etc.Theca Cells: The flattened stroma cells forming a sheath or theca outside the basal lamina lining the mature OVARIAN FOLLICLE. Thecal interstitial or stromal cells are steroidogenic, and produce primarily ANDROGENS which serve as precusors of ESTROGENS in the GRANULOSA CELLS.Hair Cells, Auditory, Outer: Sensory cells of organ of Corti. In mammals, they are usually arranged in three or four rows, and away from the core of spongy bone (the modiolus), lateral to the INNER AUDITORY HAIR CELLS and other supporting structures. Their cell bodies and STEREOCILIA increase in length from the cochlear base toward the apex and laterally across the rows, allowing differential responses to various frequencies of sound.Follicular Cyst: Cyst due to the occlusion of the duct of a follicle or small gland.Cell Differentiation: Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.Keratin-14: A type I keratin that is found associated with the KERATIN-5 in the internal stratified EPITHELIUM. Mutations in the gene for keratin-14 are associated with EPIDERMOLYSIS BULLOSA SIMPLEX.Keratins, Type II: A keratin subtype that includes keratins that are generally larger and less acidic that TYPE I KERATINS. Type II keratins combine with type I keratins to form keratin filaments.Vibrissae: Stiff hairs projecting from the face around the nose of most mammals, acting as touch receptors.Estradiol: The 17-beta-isomer of estradiol, an aromatized C18 steroid with hydroxyl group at 3-beta- and 17-beta-position. Estradiol-17-beta is the most potent form of mammalian estrogenic steroids.Progesterone: The major progestational steroid that is secreted primarily by the CORPUS LUTEUM and the PLACENTA. Progesterone acts on the UTERUS, the MAMMARY GLANDS and the BRAIN. It is required in EMBRYO IMPLANTATION; PREGNANCY maintenance, and the development of mammary tissue for MILK production. Progesterone, converted from PREGNENOLONE, also serves as an intermediate in the biosynthesis of GONADAL STEROID HORMONES and adrenal CORTICOSTEROIDS.Skin Physiological Phenomena: The functions of the skin in the human and animal body. It includes the pigmentation of the skin.Hypertrichosis: Excessive hair growth at inappropriate locations, such as on the extremities, the head, and the back. It is caused by genetic or acquired factors, and is an androgen-independent process. This concept does not include HIRSUTISM which is an androgen-dependent excess hair growth in WOMEN and CHILDREN.Regeneration: The physiological renewal, repair, or replacement of tissue.Oocytes: Female germ cells derived from OOGONIA and termed OOCYTES when they enter MEIOSIS. The primary oocytes begin meiosis but are arrested at the diplotene state until OVULATION at PUBERTY to give rise to haploid secondary oocytes or ova (OVUM).Immunohistochemistry: Histochemical localization of immunoreactive substances using labeled antibodies as reagents.Mice, Inbred C57BLEdar-Associated Death Domain Protein: A tumor necrosis factor receptor-associated factor that acts as a specific signaling adaptor protein for the EDAR RECEPTOR and plays an important role in ectodermal development. It binds to edar receptor via its C-terminal death domain region and to other specific TNF receptor-associated factors via its N-terminal domain. Loss of function of edar-associated death domain protein is associated with AUTOSOMAL RECESSIVE ANHIDROTIC ECTODERMAL DYSPLASIA.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.Gene Expression Regulation, Developmental: Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action during the developmental stages of an organism.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.Organ Culture Techniques: A technique for maintenance or growth of animal organs in vitro. It refers to three-dimensional cultures of undisaggregated tissue retaining some or all of the histological features of the tissue in vivo. (Freshney, Culture of Animal Cells, 3d ed, p1)Hedgehog Proteins: A family of intercellular signaling proteins that play and important role in regulating the development of many TISSUES and organs. Their name derives from the observation of a hedgehog-like appearance in DROSOPHILA embryos with genetic mutations that block their action.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.Luteinizing Hormone: A major gonadotropin secreted by the adenohypophysis (PITUITARY GLAND, ANTERIOR). Luteinizing hormone regulates steroid production by the interstitial cells of the TESTIS and the OVARY. The preovulatory LUTEINIZING HORMONE surge in females induces OVULATION, and subsequent LUTEINIZATION of the follicle. LUTEINIZING HORMONE consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is common in the three pituitary glycoprotein hormones (TSH, LH and FSH), but the beta subunit is unique and confers its biological specificity.Signal Transduction: The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.beta Catenin: A multi-functional catenin that participates in CELL ADHESION and nuclear signaling. Beta catenin binds CADHERINS and helps link their cytoplasmic tails to the ACTIN in the CYTOSKELETON via ALPHA CATENIN. It also serves as a transcriptional co-activator and downstream component of WNT PROTEIN-mediated SIGNAL TRANSDUCTION PATHWAYS.Oogenesis: The process of germ cell development in the female from the primordial germ cells through OOGONIA to the mature haploid ova (OVUM).Skin Neoplasms: Tumors or cancer of the SKIN.Multipotent Stem Cells: Specialized stem cells that are committed to give rise to cells that have a particular function; examples are MYOBLASTS; MYELOID PROGENITOR CELLS; and skin stem cells. (Stem Cells: A Primer [Internet]. Bethesda (MD): National Institutes of Health (US); 2000 May [cited 2002 Apr 5]. Available from: http://www.nih.gov/news/stemcell/primer.htm)Pilomatrixoma: A tumor composed of cells resembling those of the hair matrix, which undergo 'mummification' and may calcify. It is a relatively uncommon tumor, which may occur at any age from infancy. The majority of patients are under 20, and females are affected more than males. The lesion is usually a solitary deep dermal or subcutaneous tumor 3-30 mm in diameter, situated in the head, neck, or upper extremity. (From Rook et al., Textbook of Dermatology, 4th ed, p2401)Wound Healing: Restoration of integrity to traumatized tissue.Mice, Knockout: Strains of mice in which certain GENES of their GENOMES have been disrupted, or "knocked-out". To produce knockouts, using RECOMBINANT DNA technology, the normal DNA sequence of the gene being studied is altered to prevent synthesis of a normal gene product. Cloned cells in which this DNA alteration is successful are then injected into mouse EMBRYOS to produce chimeric mice. The chimeric mice are then bred to yield a strain in which all the cells of the mouse contain the disrupted gene. Knockout mice are used as EXPERIMENTAL ANIMAL MODELS for diseases (DISEASE MODELS, ANIMAL) and to clarify the functions of the genes.Melanins: Insoluble polymers of TYROSINE derivatives found in and causing darkness in skin (SKIN PIGMENTATION), hair, and feathers providing protection against SUNBURN induced by SUNLIGHT. CAROTENES contribute yellow and red coloration.Inhibins: Glycoproteins that inhibit pituitary FOLLICLE STIMULATING HORMONE secretion. Inhibins are secreted by the Sertoli cells of the testes, the granulosa cells of the ovarian follicles, the placenta, and other tissues. Inhibins and ACTIVINS are modulators of FOLLICLE STIMULATING HORMONE secretions; both groups belong to the TGF-beta superfamily, as the TRANSFORMING GROWTH FACTOR BETA. Inhibins consist of a disulfide-linked heterodimer with a unique alpha linked to either a beta A or a beta B subunit to form inhibin A or inhibin B, respectivelyWnt Proteins: Wnt proteins are a large family of secreted glycoproteins that play essential roles in EMBRYONIC AND FETAL DEVELOPMENT, and tissue maintenance. They bind to FRIZZLED RECEPTORS and act as PARACRINE PROTEIN FACTORS to initiate a variety of SIGNAL TRANSDUCTION PATHWAYS. The canonical Wnt signaling pathway stabilizes the transcriptional coactivator BETA CATENIN.Tissue Culture Techniques: A technique for maintaining or growing TISSUE in vitro, usually by DIFFUSION, perifusion, or PERFUSION. The tissue is cultured directly after removal from the host without being dispersed for cell culture.Chorionic Gonadotropin: A gonadotropic glycoprotein hormone produced primarily by the PLACENTA. Similar to the pituitary LUTEINIZING HORMONE in structure and function, chorionic gonadotropin is involved in maintaining the CORPUS LUTEUM during pregnancy. CG consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is virtually identical to the alpha subunits of the three pituitary glycoprotein hormones (TSH, LH, and FSH), but the beta subunit is unique and confers its biological specificity (CHORIONIC GONADOTROPIN, BETA SUBUNIT, HUMAN).Intermediate Filament Proteins: Filaments 7-11 nm in diameter found in the cytoplasm of all cells. Many specific proteins belong to this group, e.g., desmin, vimentin, prekeratin, decamin, skeletin, neurofilin, neurofilament protein, and glial fibrillary acid protein.Mice, Mutant Strains: Mice bearing mutant genes which are phenotypically expressed in the animals.RNA, Messenger: RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.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.Minoxidil: A potent direct-acting peripheral vasodilator (VASODILATOR AGENTS) that reduces peripheral resistance and produces a fall in BLOOD PRESSURE. (From Martindale, The Extra Pharmacopoeia, 30th ed, p371)Lymphoid Enhancer-Binding Factor 1: A T-cell factor that plays an essential role in EMBRYONIC DEVELOPMENT.Fibroblast Growth Factor 5: A fibroblast growth factor that may play a role in regulation of HAIR FOLLICLE phenotype. Spontaneous mutation of the gene for this protein results in a strain of MICE with abnormally long hair, referred to as angora mice.Animals, Newborn: Refers to animals in the period of time just after birth.Androstenedione: A delta-4 C19 steroid that is produced not only in the TESTIS, but also in the OVARY and the ADRENAL CORTEX. Depending on the tissue type, androstenedione can serve as a precursor to TESTOSTERONE as well as ESTRONE and ESTRADIOL.Eccrine Glands: Simple sweat glands that secrete sweat directly onto the SKIN.Cell Division: The fission of a CELL. It includes CYTOKINESIS, when the CYTOPLASM of a cell is divided, and CELL NUCLEUS DIVISION.Saccule and Utricle: Two membranous sacs within the vestibular labyrinth of the INNER EAR. The saccule communicates with COCHLEAR DUCT through the ductus reuniens, and communicates with utricle through the utriculosaccular duct from which the ENDOLYMPHATIC DUCT arises. The utricle and saccule have sensory areas (acoustic maculae) which are innervated by the VESTIBULAR NERVE.Merkel Cells: Modified epidermal cells located in the stratum basale. They are found mostly in areas where sensory perception is acute, such as the fingertips. Merkel cells are closely associated with an expanded terminal bulb of an afferent myelinated nerve fiber. Do not confuse with Merkel's corpuscle which is a combination of a neuron and an epidermal cell.Keratin-5: A type II keratin that is found associated with the KERATIN-14 in the internal stratified EPITHELIUM. Mutations in the gene for keratin-5 are associated with EPIDERMOLYSIS BULLOSA SIMPLEX.Sebum: The oily substance secreted by SEBACEOUS GLANDS. It is composed of KERATIN, fat, and cellular debris.Wnt Signaling Pathway: A complex signaling pathway whose name is derived from the DROSOPHILA Wg gene, which when mutated results in the wingless phenotype, and the vertebrate INT gene, which is located near integration sites of MOUSE MAMMARY TUMOR VIRUS. The signaling pathway is initiated by the binding of WNT PROTEINS to cells surface WNT RECEPTORS which interact with the AXIN SIGNALING COMPLEX and an array of second messengers that influence the actions of BETA CATENIN.Cell Proliferation: All of the processes involved in increasing CELL NUMBER including CELL DIVISION.Cattle: Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.Keratins, Type I: A keratin subtype that includes keratins that are generally smaller and more acidic that TYPE II KERATINS. Type I keratins combine with type II keratins to form keratin filaments.Estrus: The period in the ESTROUS CYCLE associated with maximum sexual receptivity and fertility in non-primate female mammals.Phenotype: The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.Follicle Stimulating Hormone, Human: A major gonadotropin secreted by the human adenohypophysis (PITUITARY GLAND, ANTERIOR). Follicle-stimulating hormone stimulates GAMETOGENESIS and the supporting cells such as the ovarian GRANULOSA CELLS, the testicular SERTOLI CELLS, and the LEYDIG CELLS. FSH consists of two noncovalently linked subunits, alpha and beta. The alpha subunit is common in the three human pituitary glycoprotein hormones (TSH, LH, and FSH), but the beta subunit is unique and confers its biological specificity.Epithelial Cells: Cells that line the inner and outer surfaces of the body by forming cellular layers (EPITHELIUM) or masses. Epithelial cells lining the SKIN; the MOUTH; the NOSE; and the ANAL CANAL derive from ectoderm; those lining the RESPIRATORY SYSTEM and the DIGESTIVE SYSTEM derive from endoderm; others (CARDIOVASCULAR SYSTEM and LYMPHATIC SYSTEM) derive from mesoderm. Epithelial cells can be classified mainly by cell shape and function into squamous, glandular and transitional epithelial cells.Gonadotropins, Equine: Gonadotropins secreted by the pituitary or the placenta in horses. This term generally refers to the gonadotropins found in the pregnant mare serum, a rich source of equine CHORIONIC GONADOTROPIN; LUTEINIZING HORMONE; and FOLLICLE STIMULATING HORMONE. Unlike that in humans, the equine LUTEINIZING HORMONE, BETA SUBUNIT is identical to the equine choronic gonadotropin, beta. Equine gonadotropins prepared from pregnant mare serum are used in reproductive studies.Ovulation Induction: Techniques for the artifical induction of ovulation, the rupture of the follicle and release of the ovum.Carcinoma, Basal Cell: A malignant skin neoplasm that seldom metastasizes but has potentialities for local invasion and destruction. Clinically it is divided into types: nodular, cicatricial, morphaic, and erythematoid (pagetoid). They develop on hair-bearing skin, most commonly on sun-exposed areas. Approximately 85% are found on the head and neck area and the remaining 15% on the trunk and limbs. (From DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p1471)Epithelium: One or more layers of EPITHELIAL CELLS, supported by the basal lamina, which covers the inner or outer surfaces of the body.Cochlea: The part of the inner ear (LABYRINTH) that is concerned with hearing. It forms the anterior part of the labyrinth, as a snail-like structure that is situated almost horizontally anterior to the VESTIBULAR LABYRINTH.Skin Pigmentation: Coloration of the skin.Anti-Mullerian Hormone: A glycoprotein that causes regression of MULLERIAN DUCTS. It is produced by SERTOLI CELLS of the TESTES. In the absence of this hormone, the Mullerian ducts develop into structures of the female reproductive tract. In males, defects of this hormone result in persistent Mullerian duct, a form of MALE PSEUDOHERMAPHRODITISM.Receptors, FSH: Cell surface proteins that bind FOLLICLE STIMULATING HORMONE with high affinity and trigger intracellular changes influencing the behavior of cells.Pregnancy: The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.Folliculitis: Inflammation of follicles, primarily hair follicles.Integrin alpha6: An integrin alpha subunit that primarily associates with INTEGRIN BETA1 or INTEGRIN BETA4 to form laminin-binding heterodimers. Integrin alpha6 has two alternatively spliced isoforms: integrin alpha6A and integrin alpha6B, which differ in their cytoplasmic domains and are regulated in a tissue-specific and developmental stage-specific manner.Cell Lineage: The developmental history of specific differentiated cell types as traced back to the original STEM CELLS in the embryo.Corpus Luteum: The yellow body derived from the ruptured OVARIAN FOLLICLE after OVULATION. The process of corpus luteum formation, LUTEINIZATION, is regulated by LUTEINIZING HORMONE.Gonadotropins: Hormones that stimulate gonadal functions such as GAMETOGENESIS and sex steroid hormone production in the OVARY and the TESTIS. Major gonadotropins are glycoproteins produced primarily by the adenohypophysis (GONADOTROPINS, PITUITARY) and the placenta (CHORIONIC GONADOTROPIN). In some species, pituitary PROLACTIN and PLACENTAL LACTOGEN exert some luteotropic activities.Bone Morphogenetic Proteins: Bone-growth regulatory factors that are members of the transforming growth factor-beta superfamily of proteins. They are synthesized as large precursor molecules which are cleaved by proteolytic enzymes. The active form can consist of a dimer of two identical proteins or a heterodimer of two related bone morphogenetic proteins.Sheep: Any of the ruminant mammals with curved horns in the genus Ovis, family Bovidae. They possess lachrymal grooves and interdigital glands, which are absent in GOATS.Embryo, Mammalian: The entity of a developing mammal (MAMMALS), generally from the cleavage of a ZYGOTE to the end of embryonic differentiation of basic structures. For the human embryo, this represents the first two months of intrauterine development preceding the stages of the FETUS.Embryonic and Fetal Development: Morphological and physiological development of EMBRYOS or FETUSES.Mice, Hairless: Mutant strains of mice that produce little or no hair.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Gene Expression: The phenotypic manifestation of a gene or genes by the processes of GENETIC TRANSCRIPTION and GENETIC TRANSLATION.Reverse Transcriptase Polymerase Chain Reaction: A variation of the PCR technique in which cDNA is made from RNA via reverse transcription. The resultant cDNA is then amplified using standard PCR protocols.Adult Stem Cells: Cells with high proliferative and self renewal capacities derived from adults.Fertilization in Vitro: An assisted reproductive technique that includes the direct handling and manipulation of oocytes and sperm to achieve fertilization in vitro.Apoptosis: One of the mechanisms by which CELL DEATH occurs (compare with NECROSIS and AUTOPHAGOCYTOSIS). Apoptosis is the mechanism responsible for the physiological deletion of cells and appears to be intrinsically programmed. It is characterized by distinctive morphologic changes in the nucleus and cytoplasm, chromatin cleavage at regularly spaced sites, and the endonucleolytic cleavage of genomic DNA; (DNA FRAGMENTATION); at internucleosomal sites. This mode of cell death serves as a balance to mitosis in regulating the size of animal tissues and in mediating pathologic processes associated with tumor growth.Organ of Corti: The spiral EPITHELIUM containing sensory AUDITORY HAIR CELLS and supporting cells in the cochlea. Organ of Corti, situated on the BASILAR MEMBRANE and overlaid by a gelatinous TECTORIAL MEMBRANE, converts sound-induced mechanical waves to neural impulses to the brain.Models, Biological: Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.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.Dental Sac: Dense fibrous layer formed from mesodermal tissue that surrounds the epithelial enamel organ. The cells eventually migrate to the external surface of the newly formed root dentin and give rise to the cementoblasts that deposit cementum on the developing root, fibroblasts of the developing periodontal ligament, and osteoblasts of the developing alveolar bone.Estrous Cycle: The period of cyclic physiological and behavior changes in non-primate female mammals that exhibit ESTRUS. The estrous cycle generally consists of 4 or 5 distinct periods corresponding to the endocrine status (PROESTRUS; ESTRUS; METESTRUS; DIESTRUS; and ANESTRUS).

Diverse developing mouse lineages exhibit high-level c-Myb expression in immature cells and loss of expression upon differentiation. (1/1203)

The c-myb gene encodes a sequence specific transactivator that is required for fetal hematopoiesis, but its potential role in other tissues is less clear because of the early fetal demise of mice with targeted deletions of the c-myb gene and incomplete of knowledge about c-myb's expression pattern. In the hematopoietic system, c-Myb protein acts on target genes whose expression is restricted to individual lineages, despite Myb's presence and role in multiple immature lineages. This suggests that c-Myb actions within different cell type-specific contexts are strongly affected by combinatorial interactions. To consider the possibility of similar c-Myb actions could extend into non-hematopoietic systems in other cell and tissue compartments, we characterized c-myb expression in developing and adult mice using in situ hybridization and correlated this with stage-specific differentiation and mitotic activity. Diverse tissues exhibited strong c-myb expression during development, notably tooth buds, the thyroid primordium, developing trachea and proximal branching airway epithelium, hair follicles, hematopoietic cells, and gastrointestinal crypt epithelial cells. The latter three of these all maintained high expression into adulthood, but with characteristic restriction to immature cell lineages prior to their terminal differentiation. In all sites, during fetal and adult stages, loss of c-Myb expression correlated strikingly with the initiation of terminal differentiation, but not the loss of mitotic activity. Based on these data, we hypothesize that c-Myb's function during cellular differentiation is both an activator of immature gene expression and a suppressor of terminal differentiation in diverse lineages.  (+info)

WNT signaling in the control of hair growth and structure. (2/1203)

Characterization of the molecular pathways controlling differentiation and proliferation in mammalian hair follicles is central to our understanding of the regulation of normal hair growth, the basis of hereditary hair loss diseases, and the origin of follicle-based tumors. We demonstrate that the proto-oncogene Wnt3, which encodes a secreted paracrine signaling molecule, is expressed in developing and mature hair follicles and that its overexpression in transgenic mouse skin causes a short-hair phenotype due to altered differentiation of hair shaft precursor cells, and cyclical balding resulting from hair shaft structural defects and associated with an abnormal profile of protein expression in the hair shaft. A putative effector molecule for WNT3 signaling, the cytoplasmic protein Dishevelled 2 (DVL2), is normally present at high levels in a subset of cells in the outer root sheath and in precursor cells of the hair shaft cortex and cuticle which lie immediately adjacent to Wnt3-expressing cells. Overexpression of Dvl2 in the outer root sheath mimics the short-hair phenotype produced by overexpression of Wnt3, supporting the hypothesis that Wnt3 and Dvl2 have the potential to act in the same pathway in the regulation of hair growth. These experiments demonstrate a previously unrecognized role for WNT signaling in the control of hair growth and structure, as well as presenting the first example of a mammalian phenotype resulting from overexpression of a Dvl gene and providing an accessible in vivo system for analysis of mammalian WNT signaling pathways.  (+info)

Procyanidin oligomers selectively and intensively promote proliferation of mouse hair epithelial cells in vitro and activate hair follicle growth in vivo. (3/1203)

We have previously reported that proanthocyanidins extracted from grape seeds possess growth-promoting activity toward murine hair epithelial cells in vitro and stimulate anagen induction in hair cycle progression in vivo. This report constitutes a comparison of the growth-promoting activity of procyanidin oligomers and the target cells of procyanidins in the skin. Results show that procyanidin dimer and trimer exhibit higher growth-promoting activity than the monomer. The maximum growth-promoting activity for hair epithelial cells with procyanidin B-2, an epicatechin dimer, reached about 300% (30 microM) relative to controls (= 100%) in a 5 d culture. Optimum concentration of procyanidin C-1, an epicatechin trimer, was lower than that of procyanidin B-2; the maximum growth-promoting activity of procyanidin C-1 was about 220% (3 microM). No other flavonoid compounds examined exhibit higher proliferative activities than the procyanidins. In skin constituent cells, only epithelial cells such as hair keratinocytes or epidermal keratinocytes respond to procyanidin oligomers. Topical application of 1% procyanidin oligomers on shaven C3H mice in the telogen phase led to significant hair regeneration [procyanidin B-2, 69.6% +/- 21.8% (mean +/- SD); procyanidin B-3, 80.9% +/- 13.0%; procyanidin C-1, 78.3% +/- 7.6%] on the basis of the shaven area; application of vehicle only led to regeneration of 41.7% (SD = 16.3%). In this paper, we demonstrate the hair-growing activity of procyanidin oligomers both in vitro and in vivo, and their potential for use as agents to induce hair growth.  (+info)

Topical gene delivery to murine skin. (4/1203)

We topically applied naked plasmid DNA containing the luciferase or chloramphenicol acetyltransferase cDNA directly to mouse skin. Gene expression was detected in skin samples as early as 4 h after DNA application, plateaued from 16 to 72 h post-application, and had decreased significantly by 7 d post-application. Reporter gene activity following topical DNA delivery was comparable with that produced by intradermal injection of DNA. Plasmid DNA at concentrations > or =0.25 microg per microl were required to achieve maximal expression levels. Reporter gene expression following topical administration was largely confined to the superficial layers of the epidermis and to hair follicles. Surprisingly, certain cationic liposomes inhibited the efficiency of cutaneous gene transfer. This technique provides a simple, clinically relevant approach to deliver genes to the skin, with potential application in treating a variety of cutaneous disorders.  (+info)

Association between mouse nude gene expression and the initiation of epithelial terminal differentiation. (5/1203)

Loss-of-function mutations in Whn (Hfh 11), a winged-helix/forkhead transcription factor, result in the nude mouse phenotype. To determine the whn expression pattern during development, we utilized mice in which a beta-galactosidase reporter gene was placed under the control of the wild-type whn promoter by homologous recombination (M. Nehls et al., 1996, Science 272, 886-889). Sites of reporter expression were confirmed by immunohistochemical staining for Whn protein or by in situ hybridization for whn mRNA. At all developmental stages, whn expression is restricted to epithelial cells. In addition to the skin and thymus, whn is expressed in the developing nails, nasal passages, tongue, palate, and teeth. In embryonic epidermis, suprabasal cells induce whn expression at the same time that terminal differentiation markers first appear. As the epidermis matures, whn promoter activity is found primarily in the first suprabasal layer, which contains keratinocytes in the early stages of terminal differentiation. In developing and mature anagen hair follicles, whn is expressed at high levels in the postmitotic precursor cells of the hair shaft and inner root sheath. Though principally associated with terminal differentiation, whn expression is also detected in progenitor cell compartments; in the hair bulb matrix and basal epidermal layer, a small subclass of cells expresses whn, while in the outer root sheath, whn promoter activity is induced as the follicle completes its elongation. Within these compartments, rare cells exhibit both whn expression and the nuclear proliferation marker Ki-67. The results suggest that whn expression encompasses the transition from a proliferative to a postmitotic state and that whn regulates the initiation of terminal differentiation.  (+info)

UVB irradiation stimulates deposition of new elastic fibers by modified epithelial cells surrounding the hair follicles and sebaceous glands in mice. (6/1203)

UVB irradiation stimulates the synthesis of elastin in the skin of humans and experimental animals. In this study we localized the site and the cells that are responsible for the synthesis of murine dermal elastic fibers. SKH-1 hairless mice were irradiated with UVB and the skin removed for light microscopy, electron microscopy, in situ hybridization, immunohistochemistry, and biochemical studies. In response to chronic low doses of UVB there was an initial moderate increase in tropoelastin mRNA in the papillary dermis. By contrast, there was a continuous marked elevation of collagen alpha1(I) message localizing to sites of inflammatory cell influx throughout the upper and lower dermis. After 25 wk of UV irradiation there was a 2-fold increase in skin elastin, yet total collagen remained unchanged. Serial desmosine analysis from en face sections indicated the increase in elastin content was due to dermal elastic fibers, an increase in the size and number of the dermal cysts, and an increase in subpanniculus elastic fibers. Elastin stains of en face sections suggested that the elastic fibers in the upper dermis were exclusively derived from cells lining the epithelial root sheath and sebaceous glands. In response to UV irradiation, the elastic fibers increased in number and size, wrapping around these structures and aligning in both directions as long fibers parallel to the body axis. Electron micrographs indicated that modified epithelial cells in close proximity to the flattened epithelial cells that encircled the root sheath and sebaceous glands were the source of the elastic fibers.  (+info)

Highly persistent label-retaining cells in the hair follicles of mice and their fate following induction of anagen. (7/1203)

We have identified some unusually persistent label-retaining cells in the hair follicles of mice, and have investigated their role in hair growth. Three-dimensional reconstruction of dorsal underfur follicles from serial sections made 14 mo after complete labeling of epidermis and hair follicles in neonatal mice disclosed the presence of highly persistent label-retaining cells associated with the first-generation follicle involved in the production of the first wave of hairs, commonly called the bulge. The label-retaining cells were most often found on the ventral surface of the first-generation follicle, five cell positions from the base, near the attachment site of the arrector pilorum muscle. No label-retaining cells were found in the hair canal, sebaceous gland, or hair germ. These label-retaining cells remained in the follicle following induction of anagen by plucking of the hairs. Surprisingly, they were not part of the first wave of mitotic activity following plucking, but instead underwent mitosis beginning 42 h after plucking. Label-retaining cells or their labeled daughters were not found in the hair germs through 48 h following induction of anagen by plucking, but instead remained in their subsebaceous follicular location even upon completion of the hair growth cycle 21 d later. These label-retaining cells are, therefore, unlikely to contribute to the formation of a new anagen follicle.  (+info)

A rapid and dynamic regulation of GDNF-family ligands and receptors correlate with the developmental dependency of cutaneous sensory innervation. (8/1203)

Glial cell line-derived neurotrophic factor (GDNF) and neurturin (NTN) are members of the transforming growth factor-beta family and have been shown to elicit neurotrophic effects upon several classes of neurons including dopaminergic neurons, motoneurons, parasympathetic, sympathetic as well as primary sensory neurons. However, there is little information available on their roles in cutaneous innervation. Herein, we have studied the regulation of gdnf, ntn and the GDNF family receptors and examined their role in the development of facial cutaneous innervation in GDNF mutant mice. A dynamic spatial and temporal regulation of gdnf, ntn and their ligand binding receptors within the follicle-sinus complex correlate with development of distinct subclasses of sensory nerve endings. Furthermore, development of NGF-dependent myelinated mechanoreceptors, i.e. reticular and transverse lanceolate endings also require GDNF during ending formation and maintenance. In addition, ligand and receptor association seems to be intricately linked to a local Schwann cell-axon interaction essential for sensory terminal formation. Our results suggests that functionally specified nerve endings depend on different GDNF family members and that in contrast to neurotrophins, this family of neurotrophic factors may be acting at local sites of terminal Schwann cell-axon growth cone interactions and that they collaborate with neurotrophins by supporting the same populations of neurons but at different times in development.  (+info)

  • Residual non-active melanocytes remain in the outer root sheath and in the bulge, which allows for repigmentation of the hair under certain stimuli or conditions. (nih.gov)
  • A.F.D delivers the hair regrowth medication directly to the outer root sheath of the hair follicle. (advancedhair.com.au)
  • The medication is absorbed under the tongue and once dissolved is delivered within 10 minutes directly within to the outer root sheath of the hair follicle. (advancedhair.com.au)
  • Using antibodies against the plaque proteins desmoplakin I and II, plakoglobin, and plakophilin 1, we have found that these occur in most, if not all hair follicle desmosomes, whereas plakophilin 2 was absent, except in the basal cells of the outer root sheath, where a weak reactivity was found. (nih.gov)
  • Basal outer root sheath cells (ORS) attached to the hair follicle glassy membrane (GM) were isolated and cultured, where they revealed greater replicative potential and longevity than ORS cells from plucked fibres. (hairfacts.com)
  • At the front-lines of this cutting-edge research stands Vancouver's " RepliCel Life Sciences Inc. ", a regenerative medicine company using cells taken from a patient's own hair follicles for the purpose of treating Androgenetic Alopecia ( Male Pattern Baldness ), aging skin and even chronic tendinosis. (hairlosstalk.com)
  • At the base of the hair follicle are sensory nerve fibers that wrap around each hair bulb. (medlineplus.gov)
  • It is related to a decrease in the number and activity of the melanocytes of the hair bulb, which eventually completely disappear from the bulb of the white hair. (nih.gov)
  • Right image shows 3D reconstruction of a confocal Z-stack of a follicle showing that most of the RFP resides in the center of the follicle bulb. (nih.gov)
  • Histology revealed that after 2 or 3 weeks in combined culture, cell interactions and tissue morphogenesis had resulted in the formation of irregular but recognizable hair fibres, produced from unusual bulb structures. (hairfacts.com)
  • It is a type of a sac, which is also called the pilosebaceous follicle, and holds the hair bulb. (laroche-posay.com)
  • Y chromosomes were also identified at the precise hair follicle location of the inflammatory infiltrate, surrounding the hair bulb in nonscarring alopecia cases and at the hair follicle bulge in sclerotic alopecia, respectively. (healio.com)
  • Of chief importance, this anatomical distribution of Y chromosomes at the respective location of inflammation in the hair follicle bulb or bulge supports the presence of graft-versus-host disease of the hair follicular unit, which has not been previously identified through the use of FISH analysis," the researchers wrote. (healio.com)
  • A) Schematic depicts follicle morphogenesis, which begins in waves in mouse backskin at approximately embryonic day 15 (~E15) and is complete at approximately postnatal day 4 (~P4). (nih.gov)
  • Colocalization of phospho-Smad1/5/8 and Dlx3 is consistent with a regulatory role for BMP signaling to Dlx3 during hair morphogenesis. (biologists.org)
  • Primary cicatricial or scarring alopecias (CA) are a group of inflammatory hair disorders of unknown pathogenesis characterized by the permanent destruction of the hair follicle. (pubmedcentralcanada.ca)
  • In secondary cicatricial alopecias, destruction of the hair follicle is incidental to a non-follicle-directed process or external injury, such as severe infections, burns, radiation, tumors, or traction. (wikipedia.org)
  • On average about 15% of the follicular units are 1-hair units (but this also may very greatly between patients). (bernsteinmedical.com)
  • If 6% of all follicles are "empty" telogen follicles, then there should be .15 x .06 = .009 or about 1% of the patient's 1-hair follicular units in the empty telogen phase that can't be identified and will be missed on dissection. (bernsteinmedical.com)
  • However, also consider that the remaining 5% of the empty follicles are associated with larger follicular units (i.e. those with 2-4 hairs). (bernsteinmedical.com)
  • If these follicular unit grafts are closely trimmed, as is the practice with very dense packing, a much more significant number of follicles are at risk of being lost. (bernsteinmedical.com)
  • These signals are ideally suited for estimating molecularly encoded hair follicular 3-D geometries, including sizes of the follicular orifices and their angles relative to the skin surface. (spiedigitallibrary.org)
  • On the other hand, when skin is exchanged between rats of different ages and thus with their hair growth waves out of phase, follicular activity in the graft skin in some circumstances comes into line with the activity of the host (Ebling & Johnson, 1961). (biologists.org)
  • As most people explore the area of hair transplantation they become aware that hair follicles and shafts do not grow from the head one by one, but rather in follicular units consisting of one to five hairs. (regrowth.com)
  • Using the lesser magnification it is possible to transect through portions of this follicular unit rendering it useless to the hair transplantation process causing a waste of precious hair. (regrowth.com)
  • The Stereo Microscopic Follicular Recovery System is the most precise method for dissection and preparation of grafts in Hair Transplantation. (regrowth.com)
  • He is devoted exclusively to doing high quality all microscopically dissected follicular unit hair transplantation with special emphasis on FUE. (regrowhair.com)
  • The data indicate that CerS4-directed epidermal ceramide composition is essential to control hair follicle stem and progenitor cell behavior potentially through its regulation of BMP and Wnt signaling. (sigmaaldrich.com)
  • Note the absence of signal from the blue (Alexa Fluor 350) fluorophore, but the bright orange-red fluorescence exhibited by the nuclei and the green emission from glycoproteins in the cytoplasm and membrane components of the individual hair follicles. (microscopyu.com)
  • Using this imaging technology, we rapidly obtain detailed three-dimensional (3-D) reconstructions of individual hair follicles. (spiedigitallibrary.org)
  • The function of hair in humans has long been a subject of interest and continues to be an important topic in society, developmental biology and medicine. (wikipedia.org)
  • For centuries, humans have ascribed esthetics to scalp hair styling and dressing and it is often used to communicate social or cultural norms in societies. (wikipedia.org)
  • The findings help explain why humans don't regenerate their hair after wounding," said senior author George Cotsarelis, MD, professor and chair of Dermatology. (redorbit.com)
  • This work uncovers a previously unidentified biological factor that specifically promotes the development of eccrine glands when these organs are interspersed with hair follicles, and has the potential to inform efforts to elucidate the genetic basis for the evolution of increased eccrine gland density in humans. (pnas.org)
  • Currently, there are no techniques that can revive dead hair follicles in humans. (reference.com)
  • If valid also in humans, hair follicle density (HFD) may relate to the perceived pleasantness of stroking tactile stimulation. (diva-portal.org)
  • Human scalp hair follicles (hHF) harbour several epithelial stem (eHFSC) and progenitor cell sub-populations organised into spatially distinct niches. (nature.com)
  • Accurately distinguishing between these ORS stem/progenitor compartments and further characterising them is critical to assess the physiological effects of intervention in translational hair research. (nature.com)
  • Propecia is an oral treatment that can only be used by men over the age of 18 and helps to inhibit DHT which is known to destroy hair follicles in male pattern baldness. (hishairclinic.com)
  • About 25 million people in Japan suffer from hair loss caused by such reasons as medication side effects and male pattern baldness. (baumanmedical.com)
  • In a prospective cohort study published in Journal of the American Academy of Dermatology , researchers described four patterns of hair loss observed in patients with cutaneous chronic graft-versus-host disease. (healio.com)
  • In scalp biopsies from female HCT recipients with male donors, fluorescent in situ hybridization (FISH) analysis was performed for XY chromosomes to identify chimerism and investigate the presence of donor chromosomes in the scalp skin and hair follicle, according to researchers. (healio.com)
  • Researchers have been making progress towards more complete, complex engineered skin , such as through the inclusion of functional hair follicles or sweat gland structures . (fightaging.org)
  • Researchers have cultured the first lab-grown skin tissue complete with hair follicles . (fightaging.org)
  • While the researchers were unable to identify exactly which types of hairs developed on the surface of the organoid, they believe the skin grew a variety of hair follicle types similar to those present naturally on the coat of a mouse. (fightaging.org)
  • After discovering this recipe for lab-grown hair follicles, the researchers must now work to overcome a new roadblock in the study of in vitro hair development - physical limitations that prevent the hairs from shedding and regenerating. (fightaging.org)
  • I'm not sure if they only do a urine screen, but if they happen to test my hair I wanna be prepared. (allnurses.com)
  • Testing the hair follicle is often thought of as more effective than urine or blood testing . (wisegeek.com)
  • While the average urine drug test will detect drug use up to 30 days prior to the test, one often-cited hair follicle drug testing advantage is that evaluation of hair may show drug use as far back as 90 days. (wisegeek.com)
  • Another advantage listed is that cutting a few hairs, usually about 100, which is very minimal, is preferable to having to provide urine or blood samples. (wisegeek.com)
  • While a urine drug screen can detect if you've used drugs in the last few days, a hair follicle drug test can detect drug use in the past 90 days. (healthline.com)
  • In addition to the variation in results depending on your family heritage, the hair tests cover a more extended time period than urine tests currently in use. (laweekly.com)
  • Hair follicle testing is typically ordered when someone desires a longer detection period than urine testing can provide. (requestatest.com)
  • In some cases, a urine drug test may be ordered along with a hair test for a more comprehensive screening. (requestatest.com)
  • There are numerous medication examinations that an organization may select, such as urine, blood, or hair follicle medication test. (duskac.com)
  • You might successfully evade urine tests with the help of fake urine but can never pass the hair test. (surfrockmusic.com)
  • Hair follicles experience several changes with aging, the most noticeable of which is graying of the hair shaft due to loss of melanin. (nih.gov)
  • Drugs are deposited in the hair shaft through absorption into the hair follicle. (askmehelpdesk.com)
  • Testing is conducted on the hair shaft which prevents external contamination on the outside of the hair that may occur during accidental exposure, such as being in the same vicinity as someone using drugs. (askmehelpdesk.com)
  • Evidence of drug use continues to live in the hair shaft long after the body and blood eliminate signs of it, and finding this evidence could be very important in any situation where there is zero tolerance for legal or illegal drug use. (wisegeek.com)
  • it does not to show up in the hair shaft. (wisegeek.com)
  • Arrows indicate hair shaft. (rxpgnews.com)
  • Small arrector pili muscles are directly connected to each hair follicle. (blausen.com)
  • Because hair follicle testing looks for drug metabolites, external or second-hand exposure should not cause a false positive result. (requestatest.com)
  • â Weâ ve found that we can influence wound healing with wnts or other proteins that allow the skin to heal in a way that has less scarring and includes all the normal structures of the skin, such as hair follicles and oil glands, rather than just a scar,â explains Cotsarelis. (rxpgnews.com)
  • Alongside hair follicles, eccrine glands are found throughout human skin and are indispensible for thermoregulation. (pnas.org)
  • The evolution of this novel physiological ability required a dramatic increase in the density and distribution of eccrine sweat glands relative to other mammals and a concomitant reduction of body hair cover. (pnas.org)
  • Differential and allelic expression analysis of the genes within this interval coupled with subsequent functional studies demonstrated that the level of En1 activity directs the relative numbers of eccrine glands and hair follicles. (pnas.org)
  • In addition to the cutaneous membrane, the integumentary system has several accessory structures including hair, hair follicles, and glands. (blausen.com)
  • Apocrine sweat glands also secrete their products directly into the hair follicle. (blausen.com)
  • Demodex infestations affect the hair follicle and attached glands, especially of the eyelids. (healthhype.com)
  • In the normal hair follicles, spectral separation of SHG signals generated by the ECM of the hair follicle from that of intrinsic cellular fluorescence revealed intricate spatial interaction of the cellular components with the surrounding connective tissue. (spiedigitallibrary.org)
  • The clinical features of all these disorders include destruction of hair follicles, progressive hair loss, and permanent replacement of the follicle with fibrous tissue. (pubmedcentralcanada.ca)
  • In addition, many patients have lowered hair density, have had multiple procedures with resulting scar tissue, or have a greater degree of baldness. (regrowth.com)
  • In addition, since excess tissue is trimmed away from the grafts, the resulting follicle grafts are smaller. (regrowth.com)
  • The shape of the tissue in culture causes the hair follicles to grow into the dermal cysts, leaving them with nowhere to shed. (fightaging.org)
  • The white thing is the base of the hair with perhaps some tissue attached to it. (healthtap.com)
  • It can be caused by a diverse group of rare disorders that destroy the hair follicle, replace it with scar tissue, and cause permanent hair loss. (wikipedia.org)
  • 2) By helping to increase circulation to the scalp: The energy from laser light can help to increase blood flow and circulation in the scalp, which can lead to healthier hair follicles and helps remove harmful elements such as DHT, the hormone responsible for hair loss. (hairsite.com)
  • Left and middle images are phase contrast and epifluorescence images, respectively, of hair follicles after dispase and collagenase treatment. (nih.gov)
  • Alternatively, find an appropriate hair treatment such as a white vinegar mix to wash the chemical residue out of your hair. (reference.com)
  • Treatment for an infected hair follicle depends on both the source of the infection and how deep it is, and can include medications such as shampoos, pills. (reference.com)
  • Put simply, this world first, patented and clinically trialled hair regrowth program, is a breakthrough in the treatment of hair loss because unlike all other medication. (advancedhair.com.au)
  • In our experience a six month A.F.D. hair regrowth program should be your starting point, because after 6 months of treatment you will start to see the results for yourself. (advancedhair.com.au)
  • In addition to your personalised AFD program, you will also receive the benefits of the FDA approved Advanced Laser Therapy Program and the Advanced Hair Fitness Range (a clinically proven scalp and follicle treatment program) all of which is included and supervised at your nearest Advanced Hair Studio/Clinic located conveniently in all major cities right across Australia and New Zealand. (advancedhair.com.au)
  • What if I am already undertaking a Hair Loss treatment with another company? (advancedhair.com.au)
  • If you are serious about undertaking a safe and proven hair regrowth treatment program then we urge you to talk to us before making any decision about how to treat your hair loss condition. (advancedhair.com.au)
  • What Are the Different Types of Hair Follicle Treatment? (wisegeek.com)
  • Hair follicle treatment will vary, depending on whether the patient has a bacterial, fungal, or viral infection. (wisegeek.com)
  • Doctors can then develop a hair follicle treatment plan, which may consist of oral or topical antibiotics , antifungal drugs, or an antiviral. (wisegeek.com)
  • If the patient has this type, hair follicle treatment will consist of an antifungal medication. (wisegeek.com)
  • Before you can order Dr. Klein's hair loss products, you need to go through a FREE no obligation consultation first to see if you are a good candidate for treatment and which prescription strength formula is most suitable for you. (hairsite.com)
  • The effectiveness of treatment depends on the cause of your hair loss and the depth of the damage. (livestrong.com)
  • However, the treatment takes five to 10 hours and would need to be performed repeatedly to create a natural appearance as hair loss continued. (dailymail.co.uk)
  • The layman's guide to hair loss and its treatment. (bernsteinmedical.com)
  • If successful, the treatment will be a game-changer for the hair restoration industry. (bernsteinmedical.com)
  • Powered by a proprietary combination of nature's well-known cure-alls, John Masters Organics' Deep Scalp Follicle Treatment & Volumizer For Thinning Hair creates the optimal conditions for fuller, healthier-looking hair. (johnmasters.com)
  • Hair transplantation is the only treatment option for patients with end-stage CCCA, and has been performed in a small number of patients but the results have been disappointing with low graft survival rates and slow regrowth of the transplanted hair. (clinicaltrials.gov)
  • State-of-the-art surgical hair restoration and advanced medical hair loss treatment to patients from New York, New Jersey, Connecticut, and around the globe. (bernsteinmedical.com)
  • Minoxidil is a topical treatment that is applied directly to the scalp twice daily and the gentle massage can sometimes help to stimulate blood flow to the hair follicles and allow its ingredients to be absorbed into the scalp. (hishairclinic.com)
  • If the bald patches can be treated before the follicles are completely destroyed there may be a chance of hair regrowth but as said before, once the treatment stops so will the hair regrowth particularly for genetic conditions. (hishairclinic.com)
  • The questionnaire should take no more than 10 minutes to complete and will provide our hair loss specialists with all the information required to recommend an effective course of home-use treatment. (belgraviacentre.com)
  • NOTE: At Bauman Medical, while we know that "hair cloning" and "hair follicle multiplication" is not yet a reality for hair restoration nor FDA-approved, Dr. Alan Bauman is always keeping a watchful eye on new stem cell hair follicle technology or related cell therapy breakthroughs that might eventually become viable and FDA-approved treatment for our hair loss patients. (baumanmedical.com)
  • I couldn't check the thing that I cut off since it fell on the floor or something but when I was cutting it I notice that there was something like tiny hairs in the hole, but I'm not really sure since ingrown hair usually occur after shaving, right? (medhelp.org)
  • Most of the skin is covered with tiny hairs growing out of the follicles. (healthresource4u.com)
  • The internal root sheath is composed of three layers, Henle's layer, Huxley's layer, and an internal cuticle that is continuous with the outermost layer of the hair fiber. (wikipedia.org)
  • Moreover, although reciprocal changes in hair cover and eccrine gland density are required for efficient thermoregulation, it is unclear if these changes are linked by a common genetic regulation. (pnas.org)
  • Six months after patients were treated with RCH-01, overall hair density increased by an average of 11.8% in ten patients out of 16. (bernsteinmedical.com)
  • The top 10 participants reported at least a 5% or greater increase in hair density at six months post-injection with an average increase of 11.8% (as reported in the May 17, 2012 announcement). (hairlosstalk.com)
  • This group demonstrated a sustained response at 24 months which averaged a 4.2% increase over baseline hair density. (hairlosstalk.com)
  • The average human head has about 100,000 hair follicles. (rxpgnews.com)
  • The Department of Health and Human Services announced via the Substance Abuse and Mental Health Services Administration that it's proposing to establish scientific and technical guidelines for the inclusion of hair specimens in the mandatory guidelines for federal workplace drug testing programs, regardless of their long-known racial disparities. (laweekly.com)
  • The question is whether gentle wounding in human subjects can cause the generation of a new hair follicle. (clinicaltrials.gov)
  • We have previously demonstrated that human NCSCs can be isolated from hair follicles. (springer.com)
  • Here, we present a protocol to isolate NCSCs from human hair follicles based on their specific surface-marker expression of CD271/HNK1 or CD271/CD49D (alpha4 integrin). (springer.com)
  • Demodex is a group of mites that can infest human hair follicles . (healthhype.com)
  • There are two main species of the Demodex mites that can infest human follicles. (healthhype.com)
  • You should know that the authorities of the World Anti Doping Agency (WADA), nowadays use hair follicle tests to detect the presence of drugs in a human. (surfrockmusic.com)
  • For example, terminal hairs grow on the scalp and lanugo hairs are seen covering the bodies of fetuses in utero and in some new born babies. (wikipedia.org)
Hair follicle | PNAS
Hair follicle | PNAS (pnas.org)
Hair loss - Wikipedia
Hair loss - Wikipedia (en.wikipedia.org)
NeoGraft Hair Transplant: Benefits, Side Effects, How it Works
NeoGraft Hair Transplant: Benefits, Side Effects, How it Works (healthline.com)
Human Skin System - Integumentary System -  and Why Hair and Nails Grow After Death | HubPages
Human Skin System - Integumentary System - and Why Hair and Nails Grow After Death | HubPages (hubpages.com)
Skin Grafts and Biologic Skin Substitutes: Overview, Relevant Anatomy, Graft Survival and Healing
Skin Grafts and Biologic Skin Substitutes: Overview, Relevant Anatomy, Graft Survival and Healing (emedicine.medscape.com)
Spots on the penis: symptoms, causes and when to worry
Spots on the penis: symptoms, causes and when to worry (netdoctor.co.uk)
Hair follicle testing?? | allnurses
Hair follicle testing?? | allnurses (allnurses.com)
Pictures of What Your Hair and Scalp Say About Your Health: Dandruff, Brittle Hair, and More
Pictures of What Your Hair and Scalp Say About Your Health: Dandruff, Brittle Hair, and More (webmd.com)
Top 10 Forensic Fails - Listverse
Top 10 Forensic Fails - Listverse (listverse.com)
In This Issue | PNAS
In This Issue | PNAS (pnas.org)
Scalp Cooling Can Help Some Breast Cancer Patients Retain Hair | UC San Francisco
Scalp Cooling Can Help Some Breast Cancer Patients Retain Hair | UC San Francisco (ucsf.edu)
Fifteen Most Common Chemotherapy Side Effects and Ways to Manage Them
Fifteen Most Common Chemotherapy Side Effects and Ways to Manage Them (medindia.net)
Regulatory mutations in TBX3 disrupt asymmetric hair pigmentation that underlies Dun camouflage color in horses | Nature...
Regulatory mutations in TBX3 disrupt asymmetric hair pigmentation that underlies Dun camouflage color in horses | Nature... (nature.com)
Folliculitis - Inflammation of Hair Follicles
Folliculitis - Inflammation of Hair Follicles (news-medical.net)
Blackhead Remover Vacuum | Clogged Hair Follicles Cleaner - Sunshine Store
Blackhead Remover Vacuum | Clogged Hair Follicles Cleaner - Sunshine Store (modernfashionclothing.com)
Health Information Center
Health Information Center (healthlibrary.epnet.com)
Come visit our Exhibit! | Smore Newsletters
Come visit our Exhibit! | Smore Newsletters (smore.com)
What is Methamphetamine - Meth Treatment | HubPages
What is Methamphetamine - Meth Treatment | HubPages (hubpages.com)
Hair Loss | Livestrong.com
Hair Loss | Livestrong.com (livestrong.com)
Overview of the Integumentary (Skin) System | BioEd Online
Overview of the Integumentary (Skin) System | BioEd Online (bioedonline.org)
Hair Follicle Drug Test: How It Works, Uses, and What to Expect
Hair Follicle Drug Test: How It Works, Uses, and What to Expect (healthline.com)
6 Facts About Alopecia | HealthCentral
6 Facts About Alopecia | HealthCentral (healthcentral.com)
How Do I Revive Dead Hair Follicles? | Reference.com
How Do I Revive Dead Hair Follicles? | Reference.com (reference.com)
Skin stem cells: rising to the surface | JCB
Skin stem cells: rising to the surface | JCB (jcb.rupress.org)
20 Surprising Reasons Your Hair is Thinning | Best Life
20 Surprising Reasons Your Hair is Thinning | Best Life (bestlifeonline.com)