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Sample records for active hair bundle

  1. Amplitude death of coupled hair bundles with stochastic channel noise

    Kim, Kyung-Joong

    2014-01-01

    Hair cells conduct auditory transduction in vertebrates. In lower vertebrates such as frogs and turtles, due to the active mechanism in hair cells, hair bundles(stereocilia) can be spontaneously oscillating or quiescent. Recently, the amplitude death phenomenon has been proposed [K.-H. Ahn, J. R. Soc. Interface, {\\bf 10}, 20130525 (2013)] as a mechanism for auditory transduction in frog hair-cell bundles, where sudden cessation of the oscillations arises due to the coupling between non-identical hair bundles. The gating of the ion channel is intrinsically stochastic due to the stochastic nature of the configuration change of the channel. The strength of the noise due to the channel gating can be comparable to the thermal Brownian noise of hair bundles. Thus, we perform stochastic simulations of the elastically coupled hair bundles. In spite of stray noisy fluctuations due to its stochastic dynamics, our simulation shows the transition from collective oscillation to amplitude death as inter-bundle coupling str...

  2. Damping Properties of the Hair Bundle

    Baumgart, Johannes; Kozlov, Andrei S.; Risler, Thomas; Hudspeth, A. James

    2015-01-01

    The viscous liquid surrounding a hair bundle dissipates energy and dampens oscillations, which poses a fundamental physical challenge to the high sensitivity and sharp frequency selectivity of hearing. To identify the mechanical forces at play, we constructed a detailed finite-element model of the hair bundle. Based on data from the hair bundle of the bullfrog's sacculus, this model treats the interaction of stereocilia both with the surrounding liquid and with the liquid in the narrow gaps b...

  3. Damping Properties of the Hair Bundle

    Baumgart, Johannes; Kozlov, Andrei S.; Risler, Thomas; Hudspeth, A. J.

    2011-11-01

    The viscous liquid surrounding a hair bundle dissipates energy and dampens oscillations, which poses a fundamental physical challenge to the high sensitivity and sharp frequency selectivity of hearing. To identify the mechanical forces at play, we constructed a detailed finite-element model of the hair bundle. Based on data from the hair bundle of the bullfrog's sacculus, this model treats the interaction of stereocilia both with the surrounding liquid and with the liquid in the narrow gaps between the individual stereocilia. The investigation revealed that grouping stereocilia in a bundle dramatically reduces the total drag. During hair-bundle deflections, the tip links potentially induce drag by causing small but very dissipative relative motions between stereocilia; this effect is offset by the horizontal top connectors that restrain such relative movements at low frequencies. For higher frequencies the coupling liquid is sufficient to assure that the hair bundle moves as a unit with a low total drag. This work reveals the mechanical characteristics originating from hair-bundle morphology and shows quantitatively how a hair bundle is adapted for sensitive mechanotransduction.

  4. Reaction–diffusion model of hair-bundle morphogenesis

    Jacobo, Adrian; Hudspeth, A. J.

    2014-01-01

    Our senses of hearing and balance rest upon the activity of hair cells, the ear’s sensory receptors. Each hair cell detects mechanical stimuli with its hair bundle, an organelle comprising 10–300 cylindrical, actin-filled stereocilia. A bundle’s structure is highly stereotyped: the stereocilia stand erect in a regular, hexagonal array and display a monotonic gradient in length along one axis. This precise organization is key to the operation of the hair bundle: mutations that disturb the morp...

  5. Hair-bundle friction from transduction channels' gating forces

    Bormuth, Volker; Barral, Jérémie; Joanny, Jean-François; Jülicher, Frank; Martin, Pascal

    2015-12-01

    Hearing starts when sound-evoked mechanical vibrations of the hair-cell bundle activate mechanosensitive ion channels, giving birth to an electrical signal. As for any mechanical system, friction impedes movements of the hair bundle and thus constrains the sensitivity and frequency selectivity of auditory transduction. We have shown recently that the opening and closing of the transduction channels produce internal frictional forces that can dominate viscous drag on the micrometer-sized hair bundle and thus provide a major source of damping [2]. We develop here a physical theory of passive hair-bundle mechanics that explains the origin of channel friction. We show that channel friction can be understood quantitatively by coupling the dynamics of the conformational change associated with channel gating to tip-link tension. As a result, varying channel properties affects friction, with faster channels producing smaller friction. The analysis emphasizes the dual role of transduction channels' gating forces, which affect both hair-bundle stiffness and drag. Friction originating from gating of ion channels is a general concept that is relevant to all mechanosensitive channels.

  6. Effectiveness of Hair Bundle Motility as the Cochlear Amplifier

    Sul, Bora; Iwasa, Kuni H.

    2009-01-01

    The effectiveness of hair bundle motility in mammalian and avian ears is studied by examining energy balance for a small sinusoidal displacement of the hair bundle. The condition that the energy generated by a hair bundle must be greater than energy loss due to the shear in the subtectorial gap per hair bundle leads to a limiting frequency that can be supported by hair-bundle motility. Limiting frequencies are obtained for two motile mechanisms for fast adaptation, the channel re-closure mode...

  7. Coupling a sensory hair-cell bundle to cyber clones enhances nonlinear amplification

    Barral, Jérémie; Dierkes, Kai; Lindner, Benjamin; Jülicher, Frank; Martin, Pascal

    2010-01-01

    The vertebrate ear benefits from nonlinear mechanical amplification to operate over a vast range of sound intensities. The amplificatory process is thought to emerge from active force production by sensory hair cells. The mechano-sensory hair bundle that protrudes from the apical surface of each hair cell can oscillate spontaneously and function as a frequency-selective, nonlinear amplifier. Intrinsic fluctuations, however, jostle the response of a single hair bundle to weak stimuli and serio...

  8. Comparative transduction mechanisms of hair cells in the bullfrog uticulus. 2: Sensitivity and response dynamics to hair bundle displacement

    Baird, Richard A.

    1994-01-01

    The present study was motivated by an interest in seeing whether hair cell types in the bullfrog utriculus might differ in their voltage responses to hair bundle displacement. Particular interest was in assessing the contributions of two factors to the responses of utricular hair cells. First, interest in examining the effect of hair bundle morphology on the sensitivity of hair cells to natural stimulation was motivated by the observation that vestibular hair cells, unlike many auditory hair cells, are not free-standing but rather linked to an accessory cupular or otolithic membrane via the tip of their kinocilium. Interest also laid in examining the contribution, if any, of adaptation to the response properties of utricular hair cells. Hair cells in auditory and vibratory inner ear endorgans adapt to maintained displacements of their hair bundles, sharply limiting their low frequency sensitivity. This adaptation is mediated by a shift in the displacement-response curve (DRC) of the hair cell along the displacement axis. Observations suggest that the adaptation process occurs within the hair bundle and precedes mechanoelectric transduction. Recent observations of time-dependent changes in hair bundle stiffness are consistent with this conclusion. Adaptation would be expected to be most useful in inner ear endorgans in which hair cells are subject to large static displacements that could potentially saturate their instantaneous response and compromise their sensitivity to high frequency stimulation. The adaptation process also permits hair cells to maintain their sensory hair bundle in the most sensitive portion of their DRC. In vestibular otolith organs in which static sensitivity is desirable, any adaptation process in the hair cells may be undesirable. The rate and extent of the decline of the voltage responses was measured of utricular hair cells to step and sinusoidal hair bundle displacements. Then for similar resting potentials and response amplitudes, the

  9. Lateral mechanical coupling of stereocilia in cochlear hair bundles.

    Langer, M G; Fink, S; Koitschev, A; Rexhausen, U; Hörber, J K; Ruppersberg, J P

    2001-06-01

    For understanding the gating process of transduction channels in the inner ear it is essential to characterize and examine the functional properties of the ultrastructure of stereociliary bundles. There is strong evidence that transduction channels in hair cells are gated by directly pulling at the so-called tip links. In addition to these tip links a second class of filamentous structures was identified in the scanning and transmission electron microscope: the side-to-side links. These links laterally connect stereocilia of the same row of a hair bundle. This study concentrates on mechanical coupling of stereocilia of the tallest row connected by side-to-side links. Atomic Force microscopy (AFM) was used to investigate hair bundles of outer hair cells (OHCs) from postnatal rats (day 4). Although hair bundles of postnatal rats are still immature at day 4 and interconnecting cross-links do not show preferential direction yet, hair bundles of investigated OHCs already showed the characteristic V-shape of mature hair cells. In a first experiment, the stiffness of stereocilia was investigated scanning individual stereocilia with an AFM tip. The spring constant for the excitatory direction was 2.5 +/- 0.6 x 10(-3) N/m whereas a higher spring constant (3.1 +/- 1.5 x 10(-3) N/m) was observed in the inhibitory direction. In a second set of experiments, the force transmission between stereocilia of the tallest row was measured using AFM in combination with a thin glass fiber. This fiber locally displaced a stereocilium while the force laterally transmitted to the neighboring untouched taller stereocilia was measured by AFM. The results show a weak force interaction between tallest stereocilia of postnatal rats. The force exerted to an individual stereocilium declines to 36% at the nearest adjacent stereocilium of the same row not touched with the fiber. It is suggested that the amount of force transmitted from a taller stereocilium to an adjacent one of the same row depends

  10. Noise alters hair-bundle mechanics at the cochlear apex

    Strimbu, C. Elliott; Fridberger, Anders

    2015-12-01

    Exposure to loud sounds can lead to both permanent and short term changes in auditory sensitivity. Permanent hearing loss is often associated with gross changes in cochlear morphology including the loss of hair cells and auditory nerve fibers while the mechanisms of short term threshold shifts are much less well understood and may vary at different locations across the cochlea. Previous reports suggest that exposure to loud sounds leads to a decrease in the cochlear microphonic potential and in the stiffness of the organ of Corti. Because the cochlear microphonic reflects changes in the membrane potential of the hair cells, this suggests that hair-bundle motion should be reversibly altered following exposure to loud sounds. Using an in vitro preparation of the guinea pig temporal bone we investigate changes in the micro-mechanical response near the cochlear apex following a brief (up to 10 - 20 minutes) exposure to loud (˜ 120 dB) tones near the best frequency at this location. We use time-resolved confocal imaging to record the motion of outer hair cell bundles before and after acoustic overstimulation. We have also recorded larger-scale structural views of the organ of Corti before and after exposure to the loud sound. Conventional electrophysiological techniques are used measure the cochlear microphonic potential. As has been previously reported, following acoustic overexposure the cochlear microphonic declines in value and typically recovers on the order of 30 - 60 minutes. Hair-bundle trajectories are affected following the loud sound and typically recover on a somewhat faster time scale than the microphonic potential, although the results vary considerably across preparations. Preliminary results also suggest reversible changes in the hair cell's resting potential following the loud sound.

  11. Actin Filament Bundles in Drosophila Wing Hairs: Hairs and Bristles Use Different Strategies for Assembly

    Guild, Gregory M.; Connelly, Patricia S.; Ruggiero, Linda; Vranich, Kelly A.; Tilney, Lewis G.

    2005-01-01

    Actin filament bundles can shape cellular extensions into dramatically different forms. We examined cytoskeleton formation during wing hair morphogenesis using both confocal and electron microscopy. Hairs elongate with linear kinetics (∼1 μm/h) over the course of ∼18 h. The resulting structure is vividly asymmetric and shaped like a rose thorn—elongated in the distal direction, curved in two dimensions with an oval base and a round tip. High-resolution analysis shows that the cytoskeleton for...

  12. Lateral mechanical coupling of stereocilia in cochlear hair bundles.

    Langer, M G; Fink, S.; Koitschev, A; Rexhausen, U; Hörber, J K; Ruppersberg, J P

    2001-01-01

    For understanding the gating process of transduction channels in the inner ear it is essential to characterize and examine the functional properties of the ultrastructure of stereociliary bundles. There is strong evidence that transduction channels in hair cells are gated by directly pulling at the so-called tip links. In addition to these tip links a second class of filamentous structures was identified in the scanning and transmission electron microscope: the side-to-side links. These links...

  13. The Hair Bundle: Fluid-Structure Interaction in the Inner Ear

    Baumgart, Johannes

    2010-01-01

    A multitude of processes cooperate to produce the sensation of sound. The key initial step, the transformation from mechanical motion into an electrical signal, takes place in highly specialized mechanosensitive organelles that are called hair bundles due to their characteristic appearance. Each hair bundle comprises many apposed cylindrical stereocilia that are located in a liquid-filled compartment of the inner ear. The viscous liquid surrounding the hair bundle dissipates energy and dampen...

  14. Cadherin-23 may be dynamic in hair bundles of the model sea anemone Nematostella vectensis.

    Pei-Ciao Tang

    Full Text Available Cadherin 23 (CDH23, a component of tip links in hair cells of vertebrate animals, is essential to mechanotransduction by hair cells in the inner ear. A homolog of CDH23 occurs in hair bundles of sea anemones. Anemone hair bundles are located on the tentacles where they detect the swimming movements of nearby prey. The anemone CDH23 is predicted to be a large polypeptide featuring a short exoplasmic C-terminal domain that is unique to sea anemones. Experimentally masking this domain with antibodies or mimicking this domain with free peptide rapidly disrupts mechanotransduction and morphology of anemone hair bundles. The loss of normal morphology is accompanied, or followed by a decrease in F-actin in stereocilia of the hair bundles. These effects were observed at very low concentrations of the reagents, 0.1-10 nM, and within minutes of exposure. The results presented herein suggest that: (1 the interaction between CDH23 and molecular partners on stereocilia of hair bundles is dynamic and; (2 the interaction is crucial for normal mechanotransduction and morphology of hair bundles.

  15. Cadherin-23 May Be Dynamic in Hair Bundles of the Model Sea Anemone Nematostella vectensis

    Pei-Ciao Tang; Watson, Glen M.

    2014-01-01

    Cadherin 23 (CDH23), a component of tip links in hair cells of vertebrate animals, is essential to mechanotransduction by hair cells in the inner ear. A homolog of CDH23 occurs in hair bundles of sea anemones. Anemone hair bundles are located on the tentacles where they detect the swimming movements of nearby prey. The anemone CDH23 is predicted to be a large polypeptide featuring a short exoplasmic C-terminal domain that is unique to sea anemones. Experimentally masking this domain with anti...

  16. Two adaptation processes in auditory hair cells together can provide an active amplifier

    Vilfan, A; Vilfan, Andrej; Duke, Thomas

    2003-01-01

    The hair cells of the vertebrate inner ear convert mechanical stimuli to electrical signals. Two adaptation mechanisms are known to modify the ionic current flowing through the transduction channels of the hair bundles: a rapid process involves calcium ions binding to the channels; and a slower adaptation is associated with the movement of myosin motors. We present a mathematical model of the hair cell which demonstrates that the combination of these two mechanisms can produce `self-tuned critical oscillations', i.e. maintain the hair bundle at the threshold of an oscillatory instability. The characteristic frequency depends on the geometry of the bundle and on the calcium dynamics, but is independent of channel kinetics. Poised on the verge of vibrating, the hair bundle acts as an active amplifier. However, if the hair cell is sufficiently perturbed, other dynamical regimes can occur. These include slow relaxation oscillations which resemble the hair bundle motion observed in some experimental preparations.

  17. Comparative transduction mechanisms of hair cells in the bullfrog utriculus. II. Sensitivity and response dynamics to hair bundle displacement

    Baird, R. A.

    1994-01-01

    1. Hair cells in whole-mount in vitro preparations of the utricular macula of the bullfrog (Rana catesbeiana) were selected according to their macular location and hair bundle morphology. The sensitivity and response dynamics of selected hair cells to natural stimulation were examined by recording their voltage responses to step and sinusoidal hair bundle displacements applied to their longest stereocilia. 2. The voltage responses of 31 hair cells to sinusoidal hair bundle displacements were characterized by their gains and phases, taken with respect to peak hair bundle displacement. The gains of Type B and Type C cells at both 0.5 and 5.0 Hz were markedly lower than those of Type F and Type E cells. Phases, with the exception of Type C cells, lagged hair bundle displacement at 0.5 Hz. Type C cells had phase leads of 25-40 degrees. At 5.0 Hz, response phases in all cells were phase lagged with respect to those at 0.5 Hz. Type C cells had larger gains and smaller phase leads at 5.0 Hz than at 0.5 Hz, suggesting the presence of low-frequency adaptation. 3. Displacement-response curves, derived from the voltage responses to 5.0-Hz sinusoids, were sigmoidal in shape and asymmetrical, with the depolarizing response having a greater magnitude and saturating less abruptly than the hyperpolarizing response. When normalized to their largest displacement the linear ranges of these curves varied from Sensitivity, defined as the slope of the normalized displacement-response curve, was inversely correlated with linear range. 4. The contribution of geometric factors associated with the hair bundle to linear range and sensitivity were predicted from realistic models of utricular hair bundles created using morphological data obtained from light and electron microscopy. Three factors, including 1) the inverse ratio of the lengths of the kinocilium and longest stereocilia, representing the lever arm between kinociliary and stereociliary displacement; 2) tip link extension

  18. Comparative transduction mechanisms of hair cells in the bullfrog utriculus. II. Sensitivity and response dynamics to hair bundle displacement

    Baird, R. A.

    1994-01-01

    1. Hair cells in whole-mount in vitro preparations of the utricular macula of the bullfrog (Rana catesbeiana) were selected according to their macular location and hair bundle morphology. The sensitivity and response dynamics of selected hair cells to natural stimulation were examined by recording their voltage responses to step and sinusoidal hair bundle displacements applied to their longest stereocilia. 2. The voltage responses of 31 hair cells to sinusoidal hair bundle displacements were characterized by their gains and phases, taken with respect to peak hair bundle displacement. The gains of Type B and Type C cells at both 0.5 and 5.0 Hz were markedly lower than those of Type F and Type E cells. Phases, with the exception of Type C cells, lagged hair bundle displacement at 0.5 Hz. Type C cells had phase leads of 25-40 degrees. At 5.0 Hz, response phases in all cells were phase lagged with respect to those at 0.5 Hz. Type C cells had larger gains and smaller phase leads at 5.0 Hz than at 0.5 Hz, suggesting the presence of low-frequency adaptation. 3. Displacement-response curves, derived from the voltage responses to 5.0-Hz sinusoids, were sigmoidal in shape and asymmetrical, with the depolarizing response having a greater magnitude and saturating less abruptly than the hyperpolarizing response. When normalized to their largest displacement the linear ranges of these curves varied from hair bundle to linear range and sensitivity were predicted from realistic models of utricular hair bundles created using morphological data obtained from light and electron microscopy. Three factors, including 1) the inverse ratio of the lengths of the kinocilium and longest stereocilia, representing the lever arm between kinociliary and stereociliary displacement; 2) tip link extension/linear displacement, largely a function of stereociliary height and separation; and 3) stereociliary number, an estimate of the number of transduction channels, were considered in this analysis

  19. Developmental regulation of planar cell polarity and hair-bundle morphogenesis in auditory hair cells: lessons from human and mouse genetics.

    Lu, Xiaowei; Sipe, Conor W

    2016-01-01

    Hearing loss is the most common and costly sensory defect in humans and genetic causes underlie a significant proportion of affected individuals. In mammals, sound is detected by hair cells (HCs) housed in the cochlea of the inner ear, whose function depends on a highly specialized mechanotransduction organelle, the hair bundle. Understanding the factors that regulate the development and functional maturation of the hair bundle is crucial for understanding the pathophysiology of human deafness. Genetic analysis of deafness genes in animal models, together with complementary forward genetic screens and conditional knock-out mutations in essential genes, have provided great insights into the molecular machinery underpinning hair-bundle development and function. In this review, we highlight recent advances in our understanding of hair-bundle morphogenesis, with an emphasis on the molecular pathways governing hair-bundle polarity and orientation. We next discuss the proteins and structural elements important for hair-cell mechanotransduction as well as hair-bundle cohesion and maintenance. In addition, developmental signals thought to regulate tonotopic features of HCs are introduced. Finally, novel approaches that complement classic genetics for studying the molecular etiology of human deafness are presented. WIREs Dev Biol 2016, 5:85-101. doi: 10.1002/wdev.202 For further resources related to this article, please visit the WIREs website. PMID:26265594

  20. LINKING DEAFNESS GENES TO HAIR-BUNDLE DEVELOPMENT AND FUNCTION

    Petit, Christine; Richardson, Guy P.

    2009-01-01

    The identification of genes underlying monogenic, early-onset forms of deafness in humans has provided unprecedented insight into the molecular mechanisms of hearing in the peripheral auditory system. The molecules involved in the development and function of the cochlea eluded characterization until recently due to the paucity of the principle cell types present in cochlear hair cells, yet a genetic approach has circumvented this problem and succeeded in identifying proteins and deciphering s...

  1. Xyloside primed glycosaminoglycans alter hair bundle micromechanical coupling and synaptic transmission: Pharmacokinetics

    Holman, Holly A.; Tran, Vy M.; Nguyen, Lynn Y.; Arungundram, Sailaja; Kalita, Mausam; Kuberan, Balagurunathan; Rabbitt, Richard D.

    2015-12-01

    Glycosaminoglycans (GAGs) are ubiquitous in the inner ear, and disorders altering their structure or production often result in debilitating hearing and balance deficits. The specific mechanisms responsible for loss of hair-cell function are not well understood. We recently reported that introduction of a novel BODIPY conjugated xyloside (BX) into the endolymph primes fluorescent GAGs in vivo [6, 15]. Confocal and two-photon fluorescence imaging revealed rapid turnover and assembly of a glycocalyx enveloping the kinocilia and extending into the cupula, a structure that presumably serves as a mechanical link between the hair bundle and the cupula. Extracellular fluorescence was also observed around the basolateral surface of hair cells and surrounding afferent nerve projections into the crista. Single unit afferent recordings during mechanical hair bundle stimulation revealed temporary interruption of synaptic transmission following BX administration followed by recovery, demonstrating an essential role for GAGs in function of the hair cell synapse. In the present work we present a pharmacokinetic model to quantify the time course of BX primed GAG production and turnover in the ear.

  2. Xyloside primed glycosaminoglycans alter hair bundle micromechanical coupling and synaptic transmission: Pharmacokinetics

    Holman, Holly A.; Nguyen, Lynn Y. [Bioengineering, University of Utah, Salt Lake City, Utah (United States); Tran, Vy M.; Arungundram, Sailaja; Kalita, Mausam [Medicinal Chemistry, University of Utah, Salt Lake City, Utah (United States); Kuberan, Balagurunathan [Medicinal Chemistry, University of Utah, Salt Lake City, Utah (United States); Neuroscience Program, University of Utah, Salt Lake City, Utah (United States); Rabbitt, Richard D. [Bioengineering, University of Utah, Salt Lake City, Utah (United States); Neuroscience Program, University of Utah, Salt Lake City, Utah (United States); Otolaryngology, University of Utah, Salt Lake City, Utah (United States); Marine Biological Laboratory, Woods Hole, Massachusetts (United States)

    2015-12-31

    Glycosaminoglycans (GAGs) are ubiquitous in the inner ear, and disorders altering their structure or production often result in debilitating hearing and balance deficits. The specific mechanisms responsible for loss of hair-cell function are not well understood. We recently reported that introduction of a novel BODIPY conjugated xyloside (BX) into the endolymph primes fluorescent GAGs in vivo [6, 15]. Confocal and two-photon fluorescence imaging revealed rapid turnover and assembly of a glycocalyx enveloping the kinocilia and extending into the cupula, a structure that presumably serves as a mechanical link between the hair bundle and the cupula. Extracellular fluorescence was also observed around the basolateral surface of hair cells and surrounding afferent nerve projections into the crista. Single unit afferent recordings during mechanical hair bundle stimulation revealed temporary interruption of synaptic transmission following BX administration followed by recovery, demonstrating an essential role for GAGs in function of the hair cell synapse. In the present work we present a pharmacokinetic model to quantify the time course of BX primed GAG production and turnover in the ear.

  3. Hair cell stereociliary bundle regeneration by espin gene transduction after aminoglycoside damage and hair cell induction by Notch inhibition.

    Taura, A; Taura, K; Koyama, Y; Yamamoto, N; Nakagawa, T; Ito, J; Ryan, A F

    2016-05-01

    Once inner ear hair cells (HCs) are damaged by drugs, noise or aging, their apical structures including the stereociliary arrays are frequently the first cellular feature to be lost. Although this can be followed by progressive loss of HC somata, a significant number of HC bodies often remain even after stereociliary loss. However, in the absence of stereocilia they are nonfunctional. HCs can sometimes be regenerated by Atoh1 transduction or Notch inhibition, but they also may lack stereociliary bundles. It is therefore important to develop methods for the regeneration of stereocilia, in order to achieve HC functional recovery. Espin is an actin-bundling protein known to participate in sterociliary elongation during development. We evaluated stereociliary array regeneration in damaged vestibular sensory epithelia in tissue culture, using viral vector transduction of two espin isoforms. Utricular HCs were damaged with aminoglycosides. The utricles were then treated with a γ-secretase inhibitor, followed by espin or control transduction and histochemistry. Although γ-secretase inhibition increased the number of HCs, few had stereociliary arrays. In contrast, 46 h after espin1 transduction, a significant increase in hair-bundle-like structures was observed. These were confirmed to be immature stereociliary arrays by scanning electron microscopy. Increased uptake of FM1-43 uptake provided evidence of stereociliary function. Espin4 transduction had no effect. The results demonstrate that espin1 gene therapy can restore stereocilia on damaged or regenerated HCs. PMID:26886463

  4. Amplifying effect of a release mechanism for fast adaptation in the hair bundle.

    Sul, Bora; Iwasa, Kuni H

    2009-07-01

    A "release" mechanism, which has been experimentally observed as the fast component in the hair bundle's response to mechanical stimulation, appears similar to common mechanical relaxation with a damping effect. This observation is puzzling because such a response is expected to have an amplifying role in the mechanoelectrical transduction process in hair cells. Here it is shown that a release mechanism can indeed have a role in amplification, if it is associated with negative stiffness due to the gating of the mechonoelectric transducer channel. PMID:19603855

  5. ACF7 Is a Hair-Bundle Antecedent, Positioned to Integrate Cuticular Plate Actin and Somatic Tubulin

    Antonellis, Patrick J.; Pollock, Lana M.; Chou, Shih-Wei; Hassan, Ahmed; Geng, Ruishuang; Chen, Xi; Fuchs, Elaine; Alagramam, Kumar N.; Auer, Manfred; McDermott, Brian M., Jr.

    2014-01-01

    The precise morphology of the mechanosensitive hair bundle requires seamless integration of actin and microtubule networks. Here, we identify Acf7a (actin crosslinking family protein 7a) as a protein positioned to bridge these distinct cytoskeletal networks in hair cells. By imaging Acf7a–Citrine fusion protein in zebrafish and immunolabeling of vestibular and cochlear mouse hair cells, we show that Acf7a and ACF7 circumscribe, underlie, and are interwoven into the cuticular plate (CP), and t...

  6. Fate of Mammalian Cochlear Hair Cells and Stereocilia after Loss of the Stereocilia

    Jia, Shuping; Yang, Shiming; Guo, Weiwei; David Z Z He

    2009-01-01

    Cochlear hair cells transduce mechanical stimuli into electrical activity. The site of hair cell transduction is the hair bundle, an array of stereocilia with different height arranged in a staircase. Tip links connect the apex of each stereocilium to the side of its taller neighbor. The hair bundle and tip links of hair cells are susceptible to acoustic trauma and ototoxic drugs. It has been shown that hair cells in lower vertebrates and in the mammalian vestibular system may survive bundle ...

  7. The actin-binding proteins eps8 and gelsolin have complementary roles in regulating the growth and stability of mechanosensory hair bundles of mammalian cochlear outer hair cells.

    Jennifer Olt

    Full Text Available Sound transduction depends upon mechanosensitive channels localized on the hair-like bundles that project from the apical surface of cochlear hair cells. Hair bundles show a stair-case structure composed of rows of stereocilia, and each stereocilium contains a core of tightly-packed and uniformly-polarized actin filaments. The growth and maintenance of the stereociliary actin core are dynamically regulated. Recently, it was shown that the actin-binding protein gelsolin is expressed in the stereocilia of outer hair cells (OHCs and in its absence they become long and straggly. Gelsolin is part of a whirlin scaffolding protein complex at the stereocilia tip, which has been shown to interact with other actin regulatory molecules such as Eps8. Here we investigated the physiological effects associated with the absence of gelsolin and its possible overlapping role with Eps8. We found that, in contrast to Eps8, gelsolin does not affect mechanoelectrical transduction during immature stages of development. Moreover, OHCs from gelsolin knockout mice were able to mature into fully functional sensory receptors as judged by the normal resting membrane potential and basolateral membrane currents. Mechanoelectrical transducer current in gelsolin-Eps8 double knockout mice showed a profile similar to that observed in the single mutants for Eps8. We propose that gelsolin has a non-overlapping role with Eps8. While Eps8 is mainly involved in the initial growth of stereocilia in both inner hair cells (IHCs and OHCs, gelsolin is required for the maintenance of mature hair bundles of low-frequency OHCs after the onset of hearing.

  8. Neutron activation analysis of human hair

    As a part of IAEA research project, ''Activation analysis of hair as an indicator of contamination of man by environmental trace element pollutants'', a survey was carried out to elucidate the levels of various trace element concentration in hair of local population in the Tokyo Metropolitan areas, by applying instrumental neutron activation analysis. A total of 202 scalp hair samples were collected from the inhabitants classified by sex and five age classes. Irradiation was made in the Rikkyo University 100 kW TRIGA MARK-II reactor. Using several combinations of irradiation time, cooling time and counting time, forty elements were determined. The relationship between several trace element contents in hair and such factors as sex, age class, hair treatment, smoking habit and dental treatment, was analyzed by using the method of multiple regression. It was shown that (1) Hair treatment had a predominant effect on the contents of bromine, magnesium and calcium in hair, (2) Aging and amoking contributed increasing mercury content in hair, and hair treatment acted reversely. (author)

  9. A nano-microstructured artificial-hair-cell-type sensor based on topologically graded 3D carbon nanotube bundles

    Yilmazoglu, O.; Yadav, S.; Cicek, D.; Schneider, J. J.

    2016-09-01

    A design for a unique artificial-hair-cell-type sensor (AHCTS) based entirely on 3D-structured, vertically aligned carbon nanotube (CNT) bundles is introduced. Standard microfabrication techniques were used for the straightforward micro-nano integration of vertically aligned carbon nanotube arrays composed of low-layer multi-walled CNTs (two to six layers). The mechanical properties of the carbon nanotube bundles were intensively characterized with regard to various substrates and CNT morphology, e.g. bundle height. The CNT bundles display excellent flexibility and mechanical stability for lateral bending, showing high tear resistance. The integrated 3D CNT sensor can detect three-dimensional forces using the deflection or compression of a central CNT bundle which changes the contact resistance to the shorter neighboring bundles. The complete sensor system can be fabricated using a single chemical vapor deposition (CVD) process step. Moreover, sophisticated external contacts to the surroundings are not necessary for signal detection. No additional sensors or external bias for signal detection are required. This simplifies the miniaturization and the integration of these nanostructures for future microsystem set-ups. The new nanostructured sensor system exhibits an average sensitivity of 2100 ppm in the linear regime with the relative resistance change per micron (ppm μm‑1) of the individual CNT bundle tip deflection. Furthermore, experiments have shown highly sensitive piezoresistive behavior with an electrical resistance decrease of up to ∼11% at 50 μm mechanical deflection. The detection sensitivity is as low as 1 μm of deflection, and thus highly comparable with the tactile hair sensors of insects, having typical thresholds on the order of 30–50 μm. The AHCTS can easily be adapted and applied as a flow, tactile or acceleration sensor as well as a vibration sensor. Potential applications of the latter might come up in artificial cochlear systems. In

  10. Progressive hearing loss and gradual deterioration of sensory hair bundles in the ears of mice lacking the actin-binding protein Eps8L2

    Furness, David N.; Johnson, Stuart L.; Manor, Uri; Rüttiger, Lukas; Tocchetti, Arianna; Offenhauser, Nina; Olt, Jennifer; Goodyear, Richard J.; Vijayakumar, Sarath; Dai, Yuhai; Hackney, Carole M.; Franz, Christoph; Di Fiore, Pier Paolo; Masetto, Sergio; Jones, Sherri M.

    2013-01-01

    Mechanotransduction in the mammalian auditory system depends on mechanosensitive channels in the hair bundles that project from the apical surface of the sensory hair cells. Individual stereocilia within each bundle contain a core of tightly packed actin filaments, whose length is dynamically regulated during development and in the adult. We show that the actin-binding protein epidermal growth factor receptor pathway substrate 8 (Eps8)L2, a member of the Eps8-like protein family, is a newly i...

  11. Characterization of adaptation motors in saccular hair cells by fluctuation analysis.

    Frank, Jonathan E.; Markin, Vladislav; Jaramillo, Fernán

    2002-01-01

    The mechanical sensitivity of hair cells, the sensory receptors of the vestibular and auditory systems, is maintained by adaptation, which resets the transducer to cancel the effects of static stimuli. Adaptation motors in hair cells can be experimentally activated by externally applying a transduction channel blocker to the hair bundle, causing the hair bundle to move in the negative direction. We studied the variance in the position of the hair bundle during these displacements and found th...

  12. Hair Growth Promotion Activity and Its Mechanism of Polygonum multiflorum

    Yunfei Li; Mingnuan Han; Pei Lin; Yanran He; Jie Yu; Ronghua Zhao

    2015-01-01

    Polygonum multiflorum Radix (PMR) has long history in hair growth promotion and hair coloring in clinical applications. However, several crucial problems in its clinic usage and mechanisms are still unsolved or lack scientific evidences. In this research, C57BL/6J mice were used to investigate hair growth promotion activity and possible mechanism of PMR and Polygonum multiflorum Radix Preparata (PMRP). Hair growth promotion activities were investigated by hair length, hair covered skin ratio,...

  13. Geometries and applications of active fiber bundles

    Giglmayr, Josef

    2001-10-01

    Active fiber bundles (FBs) are aimed to model photonic switching and processing in 3-D without the restrictions of the photonic technology. The 2-D photonic architectures are assumed to be implemented by networks of directional couplers (DCs) and Mach-Zehnder interferometers (MZIs), respectively. For the implementation several crucial problems are expected: (1) proper operation of the spatial couplers/switches (nonblocking interconnections) and (2) coupling in the interstage interconnection section mainly caused by parallel and crossing fibers/waveguides (WGs). For the design of proper operating switches (refinement of couplers) the application of decoupling concepts of modern control theory is proposed. The final goal is to translate the refined couplers into integrated photonic architectures rather than into additional lightwave circuits (LWCs) which simply would increase the coupling. The decoupling concepts are reviewed. The paper is an attempt to prepare for applying well-known system engineering concepts to the upcoming technology of photonics.

  14. Hair Growth Promotion Activity and Its Mechanism of Polygonum multiflorum

    Yunfei Li

    2015-01-01

    Full Text Available Polygonum multiflorum Radix (PMR has long history in hair growth promotion and hair coloring in clinical applications. However, several crucial problems in its clinic usage and mechanisms are still unsolved or lack scientific evidences. In this research, C57BL/6J mice were used to investigate hair growth promotion activity and possible mechanism of PMR and Polygonum multiflorum Radix Preparata (PMRP. Hair growth promotion activities were investigated by hair length, hair covered skin ratio, the number of follicles, and hair color. Regulation effects of several cytokines involved in the hair growth procedure were tested, such as fibroblast growth factor (FGF-7, Sonic Hedgehog (SHH, β-catenin, insulin-like growth factor-1 (IGF-1, and hepatocyte growth factor (HGF. Oral PMR groups had higher hair covered skin ratio (100 ± 0.00% than oral PMRP groups (48%~88%. However, topical usage of PMRP had about 90% hair covered skin ratio. Both oral administration of PMR and topically given PMRP showed hair growth promotion activities. PMR was considered to be more suitable for oral administration, while PMRP showed greater effects in external use. The hair growth promotion effect of oral PMR was most probably mediated by the expression of FGF-7, while topical PMRP promoted hair growth by the stimulation of SHH expression.

  15. Recovery of mechano-electrical transduction in rat cochlear hair bundles after postnatal destruction of the stereociliar cross-links.

    Ebert, J; Fink, S; Koitschev, A; Walther, P; Langer, M G; Lehmann-Horn, F

    2010-08-01

    Mechano-electrical transduction (MET) in the stereocilia of outer hair cells (OHCs) was studied in newborn Wistar rats using scanning electron microscopy to investigate the stereociliar cross-links, Nomarski laser differential interferometry to investigate stereociliar stiffness and by testing the functionality of the MET channels by recording the entry of fluorescent dye, FM1-43, into stereocilia. Preparations were taken from rats on their day of birth (P0) or 1-4 days later (P1-P4). Hair bundles developed from the base to the apex and from the inner to outer OHC rows. MET channel responses were detected in apical coil OHCs on P1. To study the possible recovery of MET after disrupting the cross-links, the same investigations were performed after the application of Ca(2+) chelator 1,2-bis(o-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (BAPTA) and allowing the treated samples to recover in culture medium for 0-20 h. We found that the structure and function were abolished by BAPTA. In P0-P1 samples, structural recovery was complete and the open probability of MET channels reached control values. In P3-P4 samples, complete recovery only occurred in OHCs of the outermost row. Although our results demonstrate an enormous recovery potential of OHCs in the postnatal period, the structural component restricts the potential for therapy in patients. PMID:20356889

  16. Neutron activation analysis of human hair

    In an attempt to study the availability and limitation of analytical data of human hair as an indicator of environmental pollution and/or of human health effect, concentrations of elements in 202 scalp hair samples collected from local population in the Tokyo Metropolitan area were determined by instrumental neutron activation analysis. The correlation coefficients between concentrations of 13 elements in each sex and in each age group were calculated and discussed. There were significant correlations between some pairs of elements, i.e. Na-K, Br-Cl, Ca-Zn and Ca-Mg, in all five age classes in both of male and female, indicating that the correlations were consistent. Ca was observed to be reversely correlated with Cl. No significant correlation was apparent between Hg and Se, when the correlation coefficient was calculated using logarithmic converted concentration data. (author)

  17. Neutron activation analysis of hair from breast cancer patients

    Hair samples from breast cancer patients were collected at the same time as tumour and normal tissues obtained during mastectomy, in order to determine elemental concentrations and investigate whether hair can act as an epidemiological monitor of the disease. Instrumental neutron activation analysis was used and concentrations for Na, Mg, S, Cl, Ca, Mn, Cu, Zn, Br, I, Sb, Ba, Au and Hg in the hair samples measured. No strong correlations were found between the concentrations of Cl, Cu, Zn and Br in hair and those in tumour tissues and in normal tissues. The level of Zn in the patients hair is low and that of Ca very high

  18. Human hair identification by instrumental neutron activation analysis

    Nondestructive neutron activation technique was used to analyze 17 elements (Al, As, Au, Ba, Br, Cl, Cu, Hg, I, K, Mg, Mn, Na, Sb, Sr, V and Zn) in 75 human hair samples in 5 different locations, respectively, from 15 glassware workers. The analytical results were treated further statistically to find the elemental distribution among different human hairs and to identify the individual's hair. The identifying probability of one's hair by the comparison of elemental concentrations is found to be 104-106 times higher from the same person's than from any other person's. The standard deviation of the elemental concentrations of samples taken from 5 different locations of one person is about 5 time smaller than the standard deviation for individual's hair. These data support the possibility of using NAA of hair for human hair identification. (author)

  19. Exploring the Role of Mechanotransduction Activation and Adaptation Kinetics in Hair Cell Filtering Using a Hodgkin-Huxley Approach

    Wells, Gregg B.; Ricci, Anthony J.

    2011-11-01

    In the auditory system, mechanotransduction occurs in the hair cell sensory hair bundle and is the first major step in the translation of mechanical energy into electrical. Tonotopic variations in the activation kinetics of this process are posited to provide a low pass filter to the input. An adaptation process, also associated with mechanotransduction, is postulated to provide a high pass filter to the input in a tonotopic manner. Together a bandpass filter is created at the hair cell input. Corresponding mechanical components to both activation and adaptation are also suggested to be involved in generating cochlear amplification. A paradox to this story is that hair cells where the mechanotransduction properties are most robust possess an intrinsic electrical resonance mechanism proposed to account for all required tuning and amplification. A simple Hodgkin-Huxley type model is presented to attempt to determine the role of the activation and adaptation kinetics in further tuning hair cells that exhibit electrical resonance. Results further support that steady state mechanotransduction properties are critical for setting the resting potential of the hair cell while the kinetics of activation and adaptation are important for sharpening tuning around the characteristic frequency of the hair cell.

  20. Evaluation of hair growth promoting activity of Phyllanthus niruri

    Satish Patel; Vikas Sharma; Nagendra Chauhan; Mayank Thakur; Vinod Dixit

    2015-01-01

    Objective: This study was designed to investigate the potential Phyllanthus niruri (P. niruri ) extracts in promotion of hair growth. Materials and Methods: Here, we studied the hair growth promoting activity of petroleum ether extract of P. niruri following its topical administration. Alopecia was induced in albino rats by subcutaneous administration of testosterone for 21 days. Evaluation of hair loss inhibition was done by concurrent administration of extract and monitoring parameters like...

  1. Neutron activation analysis of organohalogens in Chinese human hair

    To effectively extract organohalogens from human hair, two factors, the extracting time and hair length on the extraction efficiency of organohalogens were studied by neutron activation analysis (NAA) and gas chromatograph-electron capture detector (GC-ECD), respectively. Furthermore, the concentrations of extractable organohalogens (EOX) and extractable persistent organohalogens (EPOX) in hair samples from angioma and control babies were also measured by the established method. The results indicated that the optimal Soxhlet-extraction time for EOX and EPOX in hair was from 8 to 11 hours, and the extraction efficiencies for organochlorine pesticides in hair were in the order of powder >2 mm>5 mm. Also, the mean levels of EOCl and EPOCl in hair of the angioma babies were significantly higher than those in the control babies (PEOClEPOCl<0.05), which implied the possible relationship between the environmental pollution and angioma. (author)

  2. The calcium-activated potassium channels of turtle hair cells

    1995-01-01

    A major factor determining the electrical resonant frequency of turtle cochlear hair cells is the time course of the Ca-activated K current (Art, J. J., and R. Fettiplace. 1987. Journal of Physiology. 385:207- 242). We have examined the notion that this time course is dictated by the K channel kinetics by recording single Ca-activated K channels in inside-out patches from isolated cells. A hair cell's resonant frequency was estimated from its known correlation with the dimensions of the hair ...

  3. Use of activation analysis of hair in environmental protection

    Human hair is very suitable for use in environmental control monitoring because trace elements concentrate in it at higher levels than in most other organs. Unlike in other biological materials, the trace element contents in hair can be determined by instrumental neutron activation analysis (INAA), as the interference by 24Na can be eliminated by appropriate washing of hair, e.g., using the procedure recommended by IAEA. The methods of sampling, washing and sample analysis using INAA and neutron activation analysis with radiochemical separation are described including the recommended way of the presentation of results. The results are presented of analyses for trace elements in hair from both little and highly polluted areas. (Ha)

  4. Evaluation of hair growth promoting activity of Phyllanthus niruri

    Satish Patel

    2015-10-01

    Full Text Available Objectives: This study was designed to investigate the potential Phyllanthus niruri extracts in promotion of hair growth. Materials and Methods: Here, we studied the hair growth promoting activity of petroleum ether extract of P. niruri following its topical administration. Alopecia was induced in albino rats by subcutaneous administration of testosterone for 21 days. Evaluation of hair loss inhibition was done by concurrent administration of extract and monitoring parameters like follicular density,  anagen/telogen (A/T ratio and histological observation of animal skin sections. Finasteride solution was applied topically as standard. In vitro experiments were also performed to study the effect of extract on the activity of 5α-reductase enzyme Results: Groups treated with petroleum ether extract of plant showed hair re-growth as reflected by follicular density, A/T ratio and skin sections. Histopathology and morphologic observations of hair re-growth at shaved sites showed active follicular proliferation. In vitro experiments results showed inhibitory activity of petroleum  ether extract on type-2 5α-reductase enzyme and an increase in the amount of testosterone with increasing concentrations.  Conclusion: It could be concluded that petroleum ether extracts of P. niruri might be useful in the treatment of testosterone-induced alopecia in the experimental animal by inhibiting 5α-reductase enzyme.

  5. [Neutron activation analysis of human hair--multivariate analysis of factors influencing on trace element contents in hair-- (author's transl)].

    Imahori, A; Fukushima, I

    1980-06-01

    As a part of IAEA research project, "Activation analysis of hair as an indicator of contamination of man by environmental trace element pollutants", a survey was carried out to elucidate the levels of various trace element concentrations in hair of local population in the Tokyo Metropolitan areas, by applying instrumental neutron activation analysis. A total of 202 scalp hair samples were collected from the inhabitants classified by sex and five age classes. Irradiation was made in the Rikkyo University 100 kW TRIGA MARK-II reactor. Using several combinations of irradiation time, cooling time and counting time, forty elements were determined. The relationship between several trace element contents in hair and such factors as sex, age class, hair treatment, smoking habit and dental treatment, was analyzed by using the method of multiple regression. It was shown that (1) Hair treatment had a predominant effect on the contents of bromine, magnesium and calcium in hair, (2) Aging and smoking contributed increasing mercury content in hair, and hair treatment acted reversely. PMID:7208973

  6. Nondestructive multielementary analysis of human hair by neutron activation

    Various elements contained in human hair have been used for an index of environmental pollution effect of human body. Nondestructive neutron activation analysis was applied to hair samples on 61 inhabitants of a local district which was free from air pollution. At Rikkyo University hair samples were irradiated for 3 minutes or 15 hours (5 hours/day, 3 days) in a TRIGA Mark II Reactor with a neutron flux of 1.5x1012 n/cm2/sec. The activities were measured by a Ge(Li) detector. 18 elements could be determined: Al, Br, Ca, Cl, Cu, I, Mg, Mn, Na, S and V with the 3 minute irradiation method, and As, Au, Cr, K, La, Sb and Zn with the 15 hour irradiation method. Concentration-distribution histograms, and differences in distribution patterns of these elements caused by permanent wave treatment, sex or age were discussed. (auth.)

  7. Recovery of mechano-electrical transduction in rat cochlear hair bundles after postnatal destruction of the stereociliar cross-links

    Ebert, J.; Fink, S.; Koitschev, A; P. Walther; Langer, M G; Lehmann-Horn, F.

    2010-01-01

    Mechano-electrical transduction (MET) in the stereocilia of outer hair cells (OHCs) was studied in newborn Wistar rats using scanning electron microscopy to investigate the stereociliar cross-links, Nomarski laser differential interferometry to investigate stereociliar stiffness and by testing the functionality of the MET channels by recording the entry of fluorescent dye, FM1-43, into stereocilia. Preparations were taken from rats on their day of birth (P0) or 1–4 days later (P1–P4). Hair bu...

  8. Instrumental neutron activation analysis of fly ash, aerosols and hair

    Samples of coal, slag, emissions retained on the separating devices, fly ash, aerosols and hair taken in the area of coal-fired power plant were analyzed by means of instrumental neutron activation analysis. 13 to 23 elements were determined in the samples. The data obtained for emissions and aerosols were further evaluated by calculation of enrichment factors, correlation coefficients and by the ratio matching method. The concentrations of elements determined in the hair of the exposed group were compared with data of control and so called ''out control'' groups as well as with recent data found for hair in other countries. It can be seen from the results that arsenic is the most serious pollutant in the area. (author)

  9. Instrumental neutron activation analysis of the hair of metallurgical workers

    Hair samples were collected from 20 metallurgical workers (10 males and 10 females) and from 59 control subjects (32 males and 27 females), whose jobs do not indicate a specific occupational exposure. The concentrations of ten minor and trace elements (Al, Co, Cu, Fe, Mg, Mn, Sb, Se, V and Zn) were determined by instrumental neutron activation analysis (INAA). The statistical data distributions, the sex and age influences in these elemental concentrations and the average values obtained for the control group were compared with published data. The effect of occupational exposure to the metallic elements was reflected in elemental compositon of hair by significant higher concentration levels of Al, Co, Cu, Fe, Mg, Mn, Sb, V and Zn in the hair of the exposed group, when compared with the control group. (author)

  10. Mitochondrial aerobic respiration is activated during hair follicle stem cell differentiation, and its dysfunction retards hair regeneration

    Tang, Yan; Luo, Binping; Deng, Zhili; Wang, Ben; Liu, Fangfen; Li, Jinmao; Shi, Wei; Xie, Hongfu; Hu, Xingwang

    2016-01-01

    Background. Emerging research revealed the essential role of mitochondria in regulating stem/progenitor cell differentiation of neural progenitor cells, mesenchymal stem cells and other stem cells through reactive oxygen species (ROS), Notch or other signaling pathway. Inhibition of mitochondrial protein synthesis results in hair loss upon injury. However, alteration of mitochondrial morphology and metabolic function during hair follicle stem cells (HFSCs) differentiation and how they affect hair regeneration has not been elaborated upon. Methods. We compared the difference in mitochondrial morphology and activity between telogen bulge cells and anagen matrix cells. Expression levels of mitochondrial ROS and superoxide dismutase 2 (SOD2) were measured to evaluate redox balance. In addition, the level of pyruvate dehydrogenase kinase (PDK) and pyruvate dehydrogenase (PDH) were estimated to present the change in energetic metabolism during differentiation. To explore the effect of the mitochondrial metabolism on regulating hair regeneration, hair growth was observed after application of a mitochondrial respiratory inhibitor upon hair plucking. Results. During HFSCs differentiation, mitochondria became elongated with more abundant organized cristae and showed higher activity in differentiated cells. SOD2 was enhanced for redox balance with relatively stable ROS levels in differentiated cells. PDK increased in HFSCs while differentiated cells showed enhanced PDH, indicating that respiration switched from glycolysis to oxidative phosphorylation during differentiation. Inhibiting mitochondrial respiration in differentiated hair follicle cells upon hair plucking repressed hair regeneration in vivo. Conclusions. Upon HFSCs differentiation, mitochondria are elongated with more abundant cristae and show higher activity, accompanying with activated aerobic respiration in differentiated cells for higher energy supply. Also, dysfunction of mitochondrial respiration delays hair

  11. New method in the criminalistics: neutron-activation analysis of the human hair

    The application of the neutron activation analysis for the examination of human hair for criminological purposes is discussed. Earlier Nal scintillation detector and 256-channels analyzer were used and only form trace elements could be detected in the hair. Recently using Ge/Li detector and a 1024-channels analyzer 11 trace elements were detected in the human hair. (H.E.)

  12. Selective activation of the versican promoter by epithelial– mesenchymal interactions during hair follicle development

    Kishimoto, Jiro; Ehama, Ritsuko; Wu, Lin; Jiang, Shuwei; Jiang, Nanyan; Burgeson, Robert E.

    1999-01-01

    Interaction between the epithelium and the mesenchyme is an essential feature of organogenesis, including hair follicle formation. The dermal papilla (DP), a dense aggregate of specialized dermis-derived stromal cells located at the bottom of the follicle, is a major component of hair that signals the follicular epithelial cells to prolong the hair growth process. However, little is known about DP-specific gene activation with regard to hair induction. In this study we demonstrate that a shor...

  13. Monitoring intracellular calcium ion dynamics in hair cell populations with Fluo-4 AM.

    Kateri J Spinelli

    Full Text Available We optimized Fluo-4 AM loading of chicken cochlea to report hair-bundle Ca(2+ signals in populations of hair cells. The bundle Ca(2+ signal reported the physiological state of the bundle and cell; extruding cells had very high bundle Fluo-4 fluorescence, cells with intact bundles and tip links had intermediate fluorescence, and damaged cells with broken tip links had low fluorescence. Moreover, Fluo-4 fluorescence in the bundle correlated with Ca(2+ entry through transduction channels; mechanically activating transduction channels increased the Fluo-4 signal, while breaking tip links with Ca(2+ chelators or blocking Ca(2+ entry through transduction channels each caused bundle and cell-body Fluo-4 fluorescence to decrease. These results show that when tip links break, bundle and soma Ca(2+ decrease, which could serve to stimulate the hair cell's tip-link regeneration process. Measurement of bundle Ca(2+ with Fluo-4 AM is therefore a simple method for assessing mechanotransduction in hair cells and permits an increased understanding of the interplay of tip links, transduction channels, and Ca(2+ signaling in the hair cell.

  14. Neutron activation analysis of human hair and health

    Full text: Periodically increasing and decreasing enthusiasm has accompanied the studies of medical significance of human hair elemental composition for at least two decades. In this field, nuclear analytical methods play an extremely important role, especially the instrumental neutron activation analysis (INAA). This paper tries to add some new knowledge to this problem. There were collected and analyzed hair samples from 2 500 practically healthy inhabitants of Uzbekistan. This allowed to estimate average concentrations of elements and intervals of concentration for normal population. Average data for 11 regions of Uzbekistan were compared with medical statistics data for these regions. There were found significant correlations for some diseases. In addition were found correlations in world wide scale. These data and previously obtained data in clinical conditions allowed to elaborate algorithm of estimation of health status according to human hair elemental composition. Reliability for many cases was very high. This allows to focus for more detailed diagnostic procedures and measures for the body elemental status correction

  15. Efferent control of the electrical and mechanical properties of hair cells in the bullfrog's sacculus.

    Manuel Castellano-Muñoz

    Full Text Available BACKGROUND: Hair cells in the auditory, vestibular, and lateral-line systems respond to mechanical stimulation and transmit information to afferent nerve fibers. The sensitivity of mechanoelectrical transduction is modulated by the efferent pathway, whose activity usually reduces the responsiveness of hair cells. The basis of this effect remains unknown. METHODOLOGY AND PRINCIPAL FINDINGS: We employed immunocytological, electrophysiological, and micromechanical approaches to characterize the anatomy of efferent innervation and the effect of efferent activity on the electrical and mechanical properties of hair cells in the bullfrog's sacculus. We found that efferent fibers form extensive synaptic terminals on all macular and extramacular hair cells. Macular hair cells expressing the Ca(2+-buffering protein calretinin contain half as many synaptic ribbons and are innervated by twice as many efferent terminals as calretinin-negative hair cells. Efferent activity elicits inhibitory postsynaptic potentials in hair cells and thus inhibits their electrical resonance. In hair cells that exhibit spiking activity, efferent stimulation suppresses the generation of action potentials. Finally, efferent activity triggers a displacement of the hair bundle's resting position. CONCLUSIONS AND SIGNIFICANCE: The hair cells of the bullfrog's sacculus receive a rich efferent innervation with the heaviest projection to calretinin-containing cells. Stimulation of efferent axons desensitizes the hair cells and suppresses their spiking activity. Although efferent activation influences mechanoelectrical transduction, the mechanical effects on hair bundles are inconsistent.

  16. Human hair neutron activation analysis: analysis on population level, mapping

    Neutron activation analysis is an outstanding analytical method having very wide applications in various fields. Analysis of human hair within last decades mostly based on neutron activation analysis is a very attractive illustration of the application of nuclear analytical techniques. Very interesting question is how the elemental composition differs in different areas or cities. In this connection the present paper gives average data and maps of various localities in the vicinity of drying-out Aral Sea and of various industrial cities in Central Asia. (author)

  17. Effect of voltage dynamics on response properties in a model of sensory hair cell

    Amro, Rami

    2012-01-01

    Sensory hair cells in auditory and vestibular organs rely on active mechanisms to achieve high sensitivity and frequency selectivity. Recent experimental studies have documented self-sustained oscillations in hair cells of lower vertebrates on two distinct levels. First, the hair bundle can undergo spontaneous mechanical oscillations. Second, somatic electric voltage oscillations across the baso-lateral membrane of the hair cell have been observed. We develop a biophysical model of the bullfrog's saccular hair cell consisting of two compartments, mechanical and electrical, to study how the mechanical and the voltage oscillations interact to produce coherent self-sustained oscillations and how this interaction contributes to the overall sensitivity and selectivity of the hair cell. The model incorporates nonlinear mechanical stochastic hair bundle system coupled bi-directionally to a Hodgkin-Huxley type system describing somatic ionic currents. We isolate regions of coherent spontaneous oscillations in the par...

  18. Epithelium-Mesenchyme Interactions Control the Activity of Peroxisome Proliferator-Activated Receptor β/δ during Hair Follicle Development

    Di-Poï, Nicolas; Ng, Chuan Young; Tan, Nguan Soon; Yang, Zhongzhou; Hemmings, Brian A.; Desvergne, Béatrice; Michalik, Liliane; Wahli, Walter

    2005-01-01

    Hair follicle morphogenesis depends on a delicate balance between cell proliferation and apoptosis, which involves epithelium-mesenchyme interactions. We show that peroxisome proliferator-activated receptor beta/delta (PPARβ/δ) and Akt1 are highly expressed in follicular keratinocytes throughout hair follicle development. Interestingly, PPARβ/δ- and Akt1-deficient mice exhibit similar retardation of postnatal hair follicle morphogenesis, particularly at the hair peg stage, revealing a new imp...

  19. Foxi3 Deficiency Compromises Hair Follicle Stem Cell Specification and Activation.

    Shirokova, Vera; Biggs, Leah C; Jussila, Maria; Ohyama, Takahiro; Groves, Andrew K; Mikkola, Marja L

    2016-07-01

    The hair follicle is an ideal system to study stem cell specification and homeostasis due to its well characterized morphogenesis and stereotypic cycles of stem cell activation upon each hair cycle to produce a new hair shaft. The adult hair follicle stem cell niche consists of two distinct populations, the bulge and the more activation-prone secondary hair germ (HG). Hair follicle stem cells are set aside during early stages of morphogenesis. This process is known to depend on the Sox9 transcription factor, but otherwise the establishment of the hair follicle stem cell niche is poorly understood. Here, we show that that mutation of Foxi3, a Forkhead family transcription factor mutated in several hairless dog breeds, compromises stem cell specification. Further, loss of Foxi3 impedes hair follicle downgrowth and progression of the hair cycle. Genome-wide profiling revealed a number of downstream effectors of Foxi3 including transcription factors with a recognized function in hair follicle stem cells such as Lhx2, Runx1, and Nfatc1, suggesting that the Foxi3 mutant phenotype results from simultaneous downregulation of several stem cell signature genes. We show that Foxi3 displays a highly dynamic expression pattern during hair morphogenesis and cycling, and identify Foxi3 as a novel secondary HG marker. Absence of Foxi3 results in poor hair regeneration upon hair plucking, and a sparse fur phenotype in unperturbed mice that exacerbates with age, caused by impaired secondary HG activation leading to progressive depletion of stem cells. Thus, Foxi3 regulates multiple aspects of hair follicle development and homeostasis. Stem Cells 2016;34:1896-1908. PMID:26992132

  20. Trace element analysis of human head hair by neutron activation technique

    28 elements in reference hair sample (HH-1) and 44 hair samples of Seoul, Korea have been analyzed by instrumental neutron activation analysis. The analytical results of reference sample agreed well with those of the IAEA report within 10% deviation except those of some elements. For the 44 hair samples of Seoul, the range of content of each element is fallen in +-3σ from his mean value if rejecting one or two of the highest data. (author)

  1. Hair growth-promoting activity of hot water extract of Thuja orientalis

    Zhang, Nan-Nan; Park, Dong Ki; Park, Hye-Jin

    2013-01-01

    Background Thuja orientalis has been traditionally used to treat patients who suffer from baldness and hair loss in East Asia. The present study sought to investigate the hair growth-promoting activity of T. orientalis hot water extract and the underlying mechanism of action. Methods After T. orientalis extract was topically applied to the shaved dorsal skin of telogenic C57BL/6 N mice, the histomorphometric analysis was employed to study induction of the hair follicle cycle. To determine the...

  2. Size Scaling and Bursting Activity in Thermally Activated Breakdown of Fiber Bundles

    Yoshioka, Naoki

    2008-10-03

    We study subcritical fracture driven by thermally activated damage accumulation in the framework of fiber bundle models. We show that in the presence of stress inhomogeneities, thermally activated cracking results in an anomalous size effect; i.e., the average lifetime tf decreases as a power law of the system size tf ∼L-z, where the exponent z depends on the external load σ and on the temperature T in the form z∼f(σ/T3/2). We propose a modified form of the Arrhenius law which provides a comprehensive description of thermally activated breakdown. Thermal fluctuations trigger bursts of breakings which have a power law size distribution. © 2008 The American Physical Society.

  3. Neutron activation analysis of neonate and maternal hair sampled in areas with different levels of pollution

    Instrumental neutron activation analysis was performed on human head hair of newborns and mothers sampled in two areas with different levels of environmental exposure. The group of neonates from the exposed area (polluted by thermal power plants burning brown coal and by chemical industry) exhibited higher levels of several trace elements in hair, e.g. Se, Zn, Hg and Sb in comparison with the control group. Moreover, the mean concentrations of Se, Hg, Zn and Br in neonate hair were found to be higher than in mothers' hair. Although the study revealed statistically significant differences in the composition of neonate hair samples in areas with different levels of environmental exposure, the differences are relatively small. Only a thorough long-term study both with environmental and medical observations can prove a direct connection of the elevated levels of some trace elements in neonate hair with the higher incidence of mental diseaes of children living in the exposed area. (author)

  4. Use of neutron activation analysis for determination of gold in some human scalp hair samples

    In the Egyptian society, it is usual until now that females wear extensively gold jewelry since their birth. The present work is carried out to determine gold content in scalp hair samples from some selected female donors of various ages. Instrumental Neutron Activation Analysis, with gamma ray spectrometry was applied for this study. The obtained data are compared with the available published data for analysis of hair samples from other countries. The correlation between age and gold concentration in hair samples is discussed. Interpretation of the influence of other factors which possibly may affect the contents of gold in the analyzed hair samples is also presented. (author)

  5. Monitoring environmental pollution of arsenic and mercury through neutron activation analysis of human hair

    Hair samples from Chilean people have been analyzed using neutron activation analysis as a monitor of environmental pollution of arsenic and mercury. Water is considered to be an important means of transport of heavy metal pollution in this country. The absorption characteristics of hair for arsenic and mercury from aqueous solutions have been studied. Hair concentrates arsenic (about twofold) and mercury (about 100 fold) from water and therefore, is able to detect even low environmental levels of these elements. Arsenic and mercury are found to behave differently in their absorption behaviour along the length of the hair. (author)

  6. Evaluation of accuracy, precision and determination limit in the human hair analysis using neutron activation method

    The accuracy, precision and determination limit were evaluated for determination of Al, As, Br, Ca, Cd, Cl, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Na, Sb, Sc, Se, V and Zn in human head hair by instrumental neutron activation analysis. The precision was examined by analyzing human hair sample, and the results of relative standard deviations obtained ranged from 3.9 to 16.2%. The results accuracy was evaluated by using reference materials GBW 09101 Human Hair and NIES 5 Human Hair. Currie criterion was used for calculation of the determination limit. (author). 8 refs., 2 tabs

  7. Activation analysis of mercury in head hair of dentists

    Mercury contents in head hair of 58 dentists, working at the hospital of Nihon University School of Dentistry, were determined using neutron activation analysis. The values ranged from 2.47 ppm to 13.7 ppm. The frequency distribution of the mercury contents increased steeply at about 2 ppm to the maximum of 4 -- 5 ppm, and decreased to about 11 ppm, its distribution pattern followed a log-normal one with a median of 5.46 ppm. The dentists were divided into two groups and the mercury contents in head hair of them were compared with each other. The arithmetic and geometric means of the values for dentists who handled amalgam in dental practice were 5.66 ppm (SD +- 1.80) and 5.40 ppm (SD x/ 1.36), while those for the dentists who did not handle amalgam in dental practice were 5.96 ppm (SD +- 2.82) and 5.38 ppm (SD x/ 1.59). The values of them agreed well with each other. The arithmetic mean for all dentists was 5.79 ppm (SD +- 2.28) and the geometric mean of them was 5.40 ppm (SD x/ 1.46). They were much lower than the values reported by Suzuki, Miyazawa or Sairenji, et al. in the past year, and they agreed well to those for normal Japanese men with the same age. Therefore it is concluded that proper mercury handling might be established in the dental office. (author)

  8. Trace element determination study in human hair by neutron activation analysis

    Human hair analysis studies have been subject of continuous interest due to the fact that they can be used as an important tool to evaluate trace element levels in the human body. These determinations have been carried out to use hair for environmental and occupational monitoring, to identify intoxication or poisoning by toxic metals, to assess nutritional status, to diagnose and to prevent diseases and in forensic sciences. Although hair analysis presents several advantages over other human tissue or fluid analyses, such as organ tissue, blood, urine and saliva, there are some controversies regarding the use of hair analysis data. These controversies arise from the fact that it is difficult to establish reliable reference values for trace elements in hair. The purpose of this study was to evaluate the factors that affect element concentrations in hair samples from a population considered healthy and residing in the Sao Paulo metropolitan area. The collected human head hair was cut in small pieces, washed, dried and analyzed by neutron activation analysis (NAA). Aliquots of hair samples and synthetic elemental standards were irradiated at the IEA-R1 nuclear research reactor for 16 h under a thermal neutron flux of about 5x1012 n cm-2 s-1 for As, Br, Ca, Co, Cr, Cs, Cu, Fe, K, La, Na, Sb, Sc, Se and Zn determinations. The induced gamma activities of the standards and samples were measured using a gamma ray spectrometer coupled to an hiperpure Ge detector. For quality control of the results, IAEA- 85 Human Hair and INCT-TL-1 Tea Leaves certified reference materials (CRMs) were analyzed. Results obtained in these CRMs presented for most of elements, good agreement with the values of the certificates (relative errors less than 10%) and good precision (variation coefficients less than 13.6%). Results of replicate hair sample analysis showed good reproducibility indicating homogeneity of the prepared sample. Results obtained in the analyses of dyed and non-dyed hair

  9. Bundling in Telecommunications

    Begoña García-Mariñoso; Xavier Martinez-Giralt; Pau Olivella

    2008-01-01

    The paper offers an overview of the literature on bundling in the telecommunications sector and its application in the Spanish market. We argue that the use of bundling in the provision of services is associated to technological reasons. Therefore, there appears no need to regulate bundling activities. However, this is not to say that other related telecom markets should not be scrutinized and regulated, or that the regulator should not pay attention to other bundling-related anticompetitive ...

  10. Premature graying as a consequence of compromised antioxidant activity in hair bulb melanocytes and their precursors.

    Ying Shi

    Full Text Available Intricate coordinated mechanisms that govern the synchrony of hair growth and melanin synthesis remain largely unclear. These two events can be uncoupled in prematurely gray hair, probably due to oxidative insults that lead to the death of oxidative stress-sensitive melanocytes. In this study, we examined the gene expression profiles of middle (bulge and lower (hair bulb segments that had been micro-dissected from unpigmented and from normally pigmented hair follicles from the same donors using quantitative real-time RT-PCR (qPCR arrays. We found a significant down-regulation of melanogenesis-related genes (TYR, TYRP1, MITF, PAX3, POMC in unpigmented hair bulbs and of marker genes typical for melanocyte precursor cells (PAX3, SOX10, DCT in unpigmented mid-segments compared with their pigmented analogues. qPCR, western blotting and spin trapping assays revealed that catalase protein expression and hydroxyl radical scavenging activities are strongly repressed in unpigmented hair follicles. These data provide the first clear evidence that compromised antioxidant activity in gray hair follicles simultaneously affects mature hair bulb melanocytes and their immature precursor cells in the bulge region.

  11. Cyclic dermal BMP signalling regulates stem cell activation during hair regeneration

    Plikus, M. V.; Mayer, J. A.; de La Cruz, D.; Baker, Ruth E.; Maini, P.K.; Maxson, R.; Chuong, C M

    2008-01-01

    In the age of stem cell engineering it is critical to understand how stem cell activity is regulated during regeneration. Hairs are mini-organs that undergo cyclic regeneration throughout adult life1, and are an important model for organ regeneration. Hair stem cells located in the follicle bulge2 are regulated by the surrounding microenvironment, or niche3. The activation of such stem cells is cyclic, involving periodic -catenin activity4, 5, 6, 7. In the adult mouse, regeneration occurs in ...

  12. Activated Notch Causes Deafness by Promoting a Supporting Cell Phenotype in Developing Auditory Hair Cells

    Grace Savoy-Burke; Felicia A Gilels; Wei Pan; Diana Pratt; Jianwen Que; Lin Gan; White, Patricia M.; Kiernan, Amy E.

    2014-01-01

    Purpose To determine whether activated Notch can promote a supporting cell fate during sensory cell differentiation in the inner ear. Methods An activated form of the Notch1 receptor (NICD) was expressed in early differentiating hair cells using a Gfi1-Cre mouse allele. To determine the effects of activated Notch on developing hair cells, Gfi1-NICD animals and their littermate controls were assessed at 5 weeks for hearing by measuring auditory brainstem responses (ABRs) and distortion product...

  13. Magnetic Force Nanoprobe for Direct Observation of Audio Frequency Tonotopy of Hair Cells.

    Kim, Ji-Wook; Lee, Jae-Hyun; Ma, Ji-Hyun; Chung, Eunna; Choi, Hongsuh; Bok, Jinwoong; Cheon, Jinwoo

    2016-06-01

    Sound perception via mechano-sensation is a remarkably sensitive and fast transmission process, converting sound as a mechanical input to neural signals in a living organism. Although knowledge of auditory hair cell functions has advanced over the past decades, challenges remain in understanding their biomechanics, partly because of their biophysical complexity and the lack of appropriate probing tools. Most current studies of hair cells have been conducted in a relatively low-frequency range (perception of 20 kHz or higher. Here, we demonstrate that the magnetic force nanoprobe (MFN) has superb spatiotemporal capabilities to mechanically stimulate spatially-targeted individual hair cells with a temporal resolution of up to 9 μs, which is equivalent to approximately 50 kHz; therefore, it is possible to investigate avian hair cell biomechanics at different tonotopic regions of the cochlea covering a full hearing frequency range of 50 to 5000 Hz. We found that the variation of the stimulation frequency and amplitude of hair bundles creates distinct mechanical responsive features along the tonotopic axis, where the kinetics of the hair bundle recovery motion exhibits unique frequency-dependent characteristics: basal, middle, and apical hair bundles can effectively respond at their respective ranges of frequency. We revealed that such recovery kinetics possesses two different time constants that are closely related to the passive and active motilities of hair cells. The use of MFN is critical for the kinetics study of free-standing hair cells in a spatiotemporally distinct tonotopic organization. PMID:27215487

  14. Effect of photoperiod on reproductive activity and hair in mares.

    Kooistra, L H; Ginther, O J

    1975-10-01

    The effects of photoperiod on reproductive activity and hair changes in pony mares were studied in 2 experiments. In experiment I, the effect of a fixed daily photoperiod on the onset of the breeding season was studied in 36 mares from Nov 13, 1973, to June 13, 1974. The 4 treatment groups were as follows: daily photoperiod equivalent to the normal day length (control group); constant light 24 hours a day with no dark (L24:D0 group); 16-hour daily photoperiod with 8 hours of dark (L16:D8 group); and 9-hour daily photoperiod with 15 hours of dark (L9:D15 group). The intervals from beginning of experiment to 1st ovulation of breeding season, to shedding of hair in tufts, and to appearance of a smooth coat were shorter (P less than 0.05) for L16:D8 group (107.1 +/- 11.1, 56.0 +/- 0, and 145.8 +/- 4.0 days, respectively) than for control, L24:D0, and L9:D15 groups and were shorter (P less than 0.05) for L24:D0 group (less than 156.1 +/- 12.2, 99.5 +/- 9.5, and 173.9 +/- 9.9 days, respectively) than for control group (192.1 +/- 3.3, 134.9 +/- 8.9, and 205.0 +/- 0 days, respectively) or L9:D15 group (less than 200.3 +/- 5,8, 150.6 +/- 12.9, and 201.7 +/- 3.3 days, respectively). These intervals were not significantly different between the control group and the L9:D15 group, but fewer (P less than 0.05) mares in the L9:D15 group had at least 1 ovulation by termination of the project. In experiment II, the effect of photoperiod on onset of anestrus was studied in 3 groups of 7 mares each. Mares in group A, as part of a previous experiment, were induced to enter the breeding season earlier than normal by a gradual increase in daily photoperiod beginning on Oct 13, 1972. From Feb 16, 1973, to June 22, 1973, group A mares were maintained at a fixed daily photoperiod of 15 hours 23 minutes. Mares in group B, as part of a previous experiment, were kept under environmental conditions simulating normal conditions in southern Wisconsin. On June 22, 1973 (beginning of the present

  15. Bundled procurement

    Chen, Yongmin; Li, Jianpei

    2015-01-01

    When procuring multiple products from competing firms, a buyer may choose separate purchase, pure bundling, or mixed bundling. We show that pure bundling will generate higher buyer surplus than both separate purchase and mixed bundling, provided that trade for each good is likely to be efficient. Pure bundling is superior because it intensifies the competition between firms by reducing their cost asymmetry. Mixed bundling is inferior because it allows firms to coordinate to ...

  16. Tourist activated networks: Implications for dynamic bundling and en-route recommendations

    Zach, Florian; Gretzel, Ulrike

    2011-01-01

    This article discusses tourist-activated networks as a concept to inform technological applications supporting dynamic bundling and en route recommendations. Empirical data were collected from travelers who visited a regional destination in the US and then analyzed with respect to its network...... structure. The results indicate that the tourist-activated network for the destination is rather sparse and that there are clearly differences in core and peripheral nodes. The findings illustrate the structure of a tourist-activated network and provide implications for technology design and tourism...

  17. Activating β-catenin signaling in CD133-positive dermal papilla cells increases hair inductivity.

    Zhou, Linli; Yang, Kun; Xu, Mingang; Andl, Thomas; Millar, Sarah E; Boyce, Steven; Zhang, Yuhang

    2016-08-01

    Bioengineering hair follicles using cells isolated from human tissue remains a difficult task. Dermal papilla (DP) cells are known to guide the growth and cycling activities of hair follicles by interacting with keratinocytes. However, DP cells quickly lose their inductivity during in vitro passaging. Rodent DP cell cultures need external addition of growth factors, including WNT and BMP molecules, to maintain the hair inductive property. CD133 is expressed by a subpopulation of DP cells that are capable of inducing hair follicle formation in vivo. We report here that expression of a stabilized form of β-catenin promoted clonal growth of CD133-positive (CD133+) DP cells in in vitro three-dimensional hydrogel culture while maintaining expression of DP markers, including alkaline phosphatase (AP), CD133, and integrin α8. After a 2-week in vitro culture, cultured CD133+ DP cells with up-regulated β-catenin activity led to an accelerated in vivo hair growth in reconstituted skin compared to control cells. Further analysis showed that matrix cell proliferation and differentiation were significantly promoted in hair follicles when β-catenin signaling was up-regulated in CD133+ DP cells. Our data highlight an important role for β-catenin signaling in promoting the inductive capability of CD133+ DP cells for in vitro expansion and in vivo hair follicle regeneration, which could potentially be applied to cultured human DP cells. PMID:27312243

  18. Catching conditions of a disease with nondestructive activation analysis of hair

    The aim of this study was to recognize the body abnormalities through the determination of the metallic balance of hair. Multielement determination of the hair of a patient with acute chromium poisoning by burn from the worst clinical state to complete recovery was carried out. Al, Au, Br, Ca, Cl, Co, Cr, Cu, Fe, Hg, I, K, Mg, Mn, Na, S, Se, V and Zn were determined by nondestructive neutron activation analysis. Comparing the clinical findings and metallic balance of the patient's hair it was demonstrated that the metallic balance returned to the normal range with recovery from the sickness. (author) 6 refs.; 4 figs.; 4 tabs

  19. Determination of trace elements in scalp hair of an elderly population by neutron activation analysis

    Neutron activation analysis was applied to assess trace elements concentrations in head hair from healthy elderly people living in the Sao Paulo metropolitan area. Concentrations of As, Br, Ca, Cl, Co, Cr, Cu, Fe, K, La, Mn, Na, Sb, Se and, Zn were determined. Comparisons were made between the results obtained for dyed and non-dyed hair as well as for hair from females and males of two different age groups. The results were also compared with range values established by clinical laboratories and published data. (author)

  20. Comparison of elemental composition of hair between osteoporotic and normal women by instrumental neutron activation analysis

    Instrumental neutron activation analysis (INAA) was carried out on hair samples from a group of 20 patients undergoing a study of osteoporosis. Half of these were judged normal. Forteen elements were measured but only calcium was found to have a correlation with the disease state. Calcium levels in hair were significantly lower (99% level) in patients with osteoporosis. Conversely, calcium levels in the blood of osteoporotic patients were significantly higher (95% level) than those in normals. Though the group studied was small it is felt that levels of calcium in hair may be of value in diagnosing osteoporosis. (author)

  1. Comparison of elemental composition of hair between osteoporotic and normal women by instrumental neutron activation analysis

    Instrumental neutron activation analysis was carried out on hair samples from a group of twenty patients undergoing a study of osteoporosis. Half of these were judged normal. Fourteen elements were measured but only calcium was found to have a correlation with the disease state. Calcium levels in hair were significantly lower (99% confidence level) in patients with osteoporosis. Conversely, calcium levels in the blood of osteoporotic patients were significantly higher (95% confidence level) than those in normals. Though the group studied was small it is felt that the levels of calcium in hair may be of value in diagnosing osteoporosis. (author) 14 refs

  2. Trace element exposure in man by instrumental neutron activation analysis of hair

    A nondestructive instrumental neutron activation technique was used to analyze human hair samples collected from people living in metropolitan and rural areas in Korea. Samples were also collected from factory workers and cancer patients. Hair from metropolitan area residents contain higher concentrations of Ca, Mg, Zn, Cu, Na, Br,Mn, I and S than rural area residents. Concentrations of I and S from cancer patients, Mg, Zn, Al, Na, Mn and As from glassware workers were relatively higher. The results show that the trace element concentrations of the hair are possibly related to the trace element concentrations in the body. (author)

  3. Determination of trace elements in human hair by neutron activation analysis

    F, Al, Cl, Cr, Fe, Co, Cu, Zn, Se, Ag, I and Au have been determined in human hair with the aid of neutron activation analysis. In comparison to values given in literature the Se concentration of 0.3 ppm is low. Increased concentrations have been found of Cr and Mn in the hair of welders and of F in the hair of persons working with fluorine compounds. Women with mammary or thyroid carcinoma showed higher Zn values. In patients with goitre reduced concentrations of I have been determined. (author)

  4. Neutron activation analysis of zinc, copper, manganese, and gold in human hair of infants

    In the hair of 41 normal newborn children the trace elements zinc, copper, manganese, and gold were followed up longitudinally by neutron activation analysis, the samples (whole length of hair)) being taken at the 1st day of life, between the 63th and 109th, the 200th and 240th, the 368th and 478th as well as between the 700th and 881th day of life. The trace element changes in the hair of babies resulted in the remarkable observation that within the first 3 months of life zinc, copper and gold contents show a considerable increase, followed by a decrease. (author)

  5. Study on trace element determination in human head hair using neutron activation analysis

    Trace element determination in human hair has become increasingly popular for monitoring environmental exposure, assessing nutritional status, evaluating intoxication and diagnosing diseases. However, there are controversies of this use due to the difficulty in the removal of only exogenous origin elements from the hair, the small correlation data between elements contents in the hair and other tissues and the poor quality of analytical results for certain elements. In this study, adequate experimental conditions have been established for human scalp hair analysis in order to obtain further reliable reference value ranges. Neutron activation analysis (NAA) was used for the determination of fourteen trace elements. Irradiations were performed at the IEA-R1 nuclear research reactor. Aliquots of samples from three individuals were analyzed and the results presented good reproducibility, indicating the sample homogeneity. The quality control of the results was assessed analyzing certified materials. The relative errors lower than 8% and relative standard deviations varying from 1.2 to 15% were obtained for most of elements in the reference materials analysis. Hair samples from voluntary donors from Sao Paulo State, aged from 15 to 60 years were studied and the results obtained indicate that As, Co, Cr, Cs, La, Sb, Sc and Se are present in the hair at a low level of 7g kg-1 and the elements Br, Ca, Fe, K, Na and Zn, at μg kg-1 level. There is a necessity of obtaining reliable reference values or intervals for hair trace elements for a defined healthy population. (author)

  6. Neutron activation analysis of children's hair from Ongudai district of Altai

    In the present study neutron activation analysis was used to determine short-lived isotopes (Na, Mg, Al, S, Cl, K, Ca, V, Mn, Cu and I) in the hair of Altai children from four villages in Ongudai district of the Altai Republic. Data for 54 boys and 132 girls at the age of 7 to 17 were analyzed. Significantly higher content of sodium, aluminum and chlorine was observed in the hair of boys over girls. Concentrations of magnesium and calcium were significantly higher in the hair of girls. Iodine, copper, manganese and sulfur concentrations in the hair of boys and girls are close to each other, the differences between the sexes are not significant. Median concentrations of the studied elements in the hair of boys and girls were, respectively: Na - 75 and 50; Mg - 49 and 62; Al - 21 and 13; S - 41150 and 39850; Cl - 1020 and 390; Ca - 608 and 973; Mn - 1.1 and 0.82; Cu - 9; I - 0.2 g/g. It was shown that the high content of calcium and magnesium is observed in the hair of children living in rural areas with high hardness and salinity of drinking water. Iodine concentrations in the hair of studied cohort of children is low, especially in puberty

  7. Instrumental neutron activation analysis of human hair and related radiotracer experiments on washing and leaching

    The work done under the IAEA-contract 2440/RB is summarized. The aim was to develop a fast and reliable system for the determination of tracer elements in human head hair by instrumental neutron activation analysis (INAA) and radiotracer washing experiments. The standardized procedure for INAA was applied to hair samples collected by the Coronel Laboratory of the University of Amsterdam. The correlation between trace element contents is considered

  8. In vivo Hair Growth Activity of Herbal Formulations

    M. Semalty; Semalty, A; Geeta P. Joshi; M. S. M Rawat

    2010-01-01

    The present study deals with the assessment of hair growth potential of three plants, Semecarpus anacardium, Trigonella foenumgraecum and Trigonella corniculata. Petroleum ether and ethanolic extracts of all the plants were prepared. Aloe vera gel (prepared with fresh Aloe vera leaves) based herbal formulations were prepared with both types of extracts of each plant. The formulations were subjected to characterization of pH, texture, odour and toxicity studies. Hair growth activity of the for...

  9. Neutron activation analysis of manganese in human hair and serum

    Objective and method of manganese determination in human hair and serum in toxicology are presented considering the occupational exposure of welders. The results are discussed in detail with regard to the frequency distribution and to the reliability of identification of welders and non-welders. (author)

  10. Hair growth activity of Crataegus pinnatifida on C57BL/6 mouse model.

    Shin, Heon-Sub; Lee, Jung-Min; Park, Sang-Yong; Yang, Jung-Eun; Kim, Ju-Han; Yi, Tae-Hoo

    2013-09-01

    Crataegus pinnatifida has a long history of use in traditional oriental herbal medicine to stimulating digestion and improving blood circulation. Based on nutrition of hair, the present study was conducted to assess the effect of C. pinnatifida extract on hair growth using mouse model and its mechanisms of action. The C. pinnatifida extract containing the contents of total polyphenol of 5.88□0.82 g gallic acid/100 g extract and proanthocyanidin of 9.15□1.58 mg cyaniding chloride/100 g extract was orally administered daily at a dosage of 50 mg/kg weight to the 7-week-old C57BL/6 mice in telogen. The C. pinnatifida extract promoted hair growth by inducing anagen phase in mice in telogen, reflected by color of skin, thickness of hair shaft, and density of hair. The ratio of anagento telogen was determined by shape of hair follicles in vertically sectioned slide and increased by oral administration of C. pinnatifida extract. The number and the size of hair follicles were also enlarged, indicating anagen phase induction. The proliferation of human dermal papilla cells (hDPC) was accelerated by addition of C. pinnatifida extract, which activated the signaling of mitogen-activated protein kinases (Erk, p-38, and JNK) and Akt. Moreover, the ratio of Bcl-2/Bax as the determinant of cell fate was also raised in skin. These results suggest that the C. pinnatifida extract promotes hair growth by inducing anagen phase, which might be mediated by the activation of cellular signalings that enhance the survival of cultured hDPC and the increase of the ratio of Bcl-2 to Bax that protects cells against cell death. PMID:23148028

  11. Determination of trace elements in human head hair by neutron activation analysis

    Instrumental neutron activation analysis was used to measure concentrations of elements in hair samples from a group of patients of a medical clinic and from a control group. Elements Al, As, Br, Ca, Cd, Cl, Co, Cu, Fe, Hg, K, Mg, Mn, Na, Sb, Sc, Se, V and Zn were analyzed and comparisons were made between the results obtained for these two groups of individuals. Normal ranges for elemental hair by commercial laboratories are also presented, for comparison, with those results obtained for the control group of individuals living in Sao Paulo, Brazil. Precision and accuracy of the results were evaluated by analyzing NIES No. 5 Human Hair and SHINR GBW09101 Human Hair reference materials. (author)

  12. Instrumental neutron activation analysis of hair for mercury determination in case of possible professional contamination. 1

    The results of neutron-activation determination of Hg in hair of the staff working with laboratory Hg-equipment are presented. The accuracy of the analysis has been tested including the possible Hg losses from phenol-formaldehyde resigns base standards in Al foils and from hair samples in polyethylene ampoules during their irradiation in water-filled nuclear reactor channel. The mean content of Hg in hair has been found to be 1.42+-0.42 (n=22) for the staff, and 1.05+-0.21 (n=10) μg for the controls. A staff group with a higher Hg content in hair (7.3+-3.0, n=10) has been singled out

  13. Forensic and environmental aspects of neutron activation analysis of single human hairs

    A new analytical procedure consisting of special washing step, irradiation in a thermal neutron flux of 1014n cm-2s-1, and Ge(Li) spectrometry enabled to determine as many as 14 elements in a 3 cm segment of a single human hair by neutron activation analysis. The criminalistic aspects of hair analysis were studied using a new statistical criterion for elimination/identification and an appropriate computer program was constructed. Hair dimensions as measured microscopically were used as additional individualizing attributes. It was shown that despite the dif--ficulties originating from from a relatively large intrinsic variation of the trace element concentration over one head, elimination of most or nearly all of the ''suspects'' could be achieved in simulated cases. Distincly elevated levels of Au as well as Cu and Ag were found in hair of some groups of persons working under specific conditions thus confirming the importance of the environmental factor related to some kinds of occupation. (author)

  14. Neutron activation analysis of single human hairs and possible applications for forensic purposes

    A new analytical procedure that enables to determine more than 10 trace elements in single, 3 cm human hair segments by neutron activation analysis (NAA) was elaborated. Application of a special washing procedure of hair (before irradiation) made possible to lower sodium content by two orders of magnitude without affecting trace element content. After irradiation in the thermal neutron flux of about 1014n.cm-2.sec-1 the activity of hair was measured with 70 cm3Ge(Li) detector coupled to 4000 channel pulse height analyser. As an alternative method, a destructive version of NAA with ion exchange group separation of radionuclides was applied. It was found that sometimes high gradients of element concentration along the hair length exist and that there is without any doubt a distinct influence of environmental factor on the content of some trace elements in hair. The criminalistic aspects of hair analysis were also studied using new statistical criterion for elimination (identification). Both possibilities and limitations of the method are discussed. (author)

  15. Neutron activation and electron microscopy in the study of human hair and breast tissues

    Methods for the preparation of hair samples and soft tissue samples employed in instrumental neutron activation analysis and in electron probe microanalysis are given. Realistic values of detection limits for liver, muscle, hair and nail samples are found for different irradiation and counting conditions in both techniques. The variation of flux in the reactor core affects the intensity of the activity produced in the sample, so method and results of measurement of these variations were investigated and are presented. Hair and nail samples collected from a selected population group in Africa were analysed using the above described techniques, as were hair samples collected from breast cancer patients and both sets of results are given. The distribution of some elements along selected lines on the hair cross section were studied using the electron probe microanalyser, whereas the elemental content of microvolumes in both pigmented and matrix areas in the hair cross section were looked at using the transmission electron microscope with electron probe microanalyser. Cancerous and non-cancerous breast tissues were analysed for their elemental content. (author)

  16. 32P measurement and dose conversion factor evaluation of activated human hair by criticality accident

    In order to conduct dose assessment of victims in criticality accidents, a method of fast neutron capture-activated 32P measurement of hair in which samples are treated by a chemical and analytical procedure that takes 9 h and measurement is conducted by liquid scintillation counting is presented. To validate this measurement method, hair samples spiked with a 32P reference source were measured and the results analysed and the optimal sample mass and detection efficiency were determined. To verify the correlation between 32P-specific activity and absorbed dose for spectra with two neutron mean energies, samples collected from three normal individuals were irradiated at various neutron energies and irradiation times using the MC50 Cyclotron of the Korea Institute of Radiological and Medical Sciences. The 32P-specific activity trend of the irradiated hair agreed well with the absorbed doses. Based on the results, dose conversion factors, which were 0.67±0.15 and 0.59±0.06 Gy (Bq g-1)-1 at neutron mean energies of 2.33 and 5.36 MeV, respectively, were calculated as a guide for medical treatment of criticality accident victims. In this study, a method for measuring 32P changes activated by the neutron irradiation of hair samples of criticality accident victims was developed and tested. In addition, a dose conversion factor for two neutron mean energy spectra based on these measurement results was developed. These results agree well with measured absorbed doses from exposure to fast neutron fields. The advantage of the proposed activated hair analysis method based on liquid scintillation counting is that it enables the acquisition of dose information from victims in a short time and with relatively high detection efficiency. In addition, sampling of hair is simpler than it is for other biological samples, and, finally, the conversion factor the authors developed using hair analysis data will be useful for dose assessment in real cases. However, the relation between

  17. Cyclic dermal BMP signaling regulates stem cell activation during hair regeneration

    Plikus, Maksim V; Mayer, Julie; de la Cruz, Damon; Baker, Ruth E.; Maini, Philip K.; Maxson, Robert; Chuong, Cheng-ming

    2008-01-01

    In the age of stem cell engineering, it is critical to understand how stem cell activity is regulated during regeneration. Hairs are mini-organs that undergo cyclic regeneration throughout adult life,1 and are an important model for organ regeneration. Hair stem cells located in the follicle bulge2 are regulated by the surrounding micro-environment, or niche3. The activation of such stem cells is cyclic, involving periodic β-catenin activity4–7. In adult mouse, regeneration occurs in waves in...

  18. Intra- and extracellular calcium modulates stereocilia stiffness on chick cochlear hair cells.

    Pae, S S; Saunders, J. C.

    1994-01-01

    Segments of the chick basilar papilla were isolated and maintained in culture medium. The sensory hair bundle of individual hair cells was observed with light microscopy and stimulated with a water microjet at 600 Hz. Hair bundle motion was slowed by illuminating the microscope with stroboscopic light, and water jet intensity was systematically varied in decibel (dB) steps until a visual detection level (VDL) threshold of hair bundle motion was achieved. The VDL threshold of many hair cells w...

  19. Developmental and activity-dependent plasticity of filiform hair receptors in the locust

    HaraldWolf

    2013-08-01

    Full Text Available A group of wind sensitive filiform hair receptors on the locust thorax and head makes contact onto a pair of identified interneuron, A4I1. The hair receptors’ central nervous projections exhibit pronounced structural dynamics during nymphal development, for example, by gradually eliminating their ipsilateral dendritic field while maintaining the contralateral one. These changes are dependent not only on hormones controlling development but on neuronal activity as well. The hair-to-interneuron system has remarkably high gain (close to 1 and makes contact to flight steering muscles. During stationary flight in front of a wind tunnel, interneuron A4I1 is active in the wing beat rhythm, and in addition it responds strongly to stimulation of sensory hairs in its receptive field. A role of the hair-to-interneuron in flight steering is thus suggested. This system appears suitable for further study of developmental and activity-dependent plasticity in a sensorimotor context with known connectivity patterns.

  20. Valproic acid induces hair regeneration in murine model and activates alkaline phosphatase activity in human dermal papilla cells.

    Soung-Hoon Lee

    Full Text Available BACKGROUND: Alopecia is the common hair loss problem that can affect many people. However, current therapies for treatment of alopecia are limited by low efficacy and potentially undesirable side effects. We have identified a new function for valproic acid (VPA, a GSK3β inhibitor that activates the Wnt/β-catenin pathway, to promote hair re-growth in vitro and in vivo. METHODOLOGY/ PRINCIPAL FINDINGS: Topical application of VPA to male C3H mice critically stimulated hair re-growth and induced terminally differentiated epidermal markers such as filaggrin and loricrin, and the dermal papilla marker alkaline phosphatase (ALP. VPA induced ALP in human dermal papilla cells by up-regulating the Wnt/β-catenin pathway, whereas minoxidil (MNX, a drug commonly used to treat alopecia, did not significantly affect the Wnt/β-catenin pathway. VPA analogs and other GSK3β inhibitors that activate the Wnt/β-catenin pathway such as 4-phenyl butyric acid, LiCl, and BeCl(2 also exhibited hair growth-promoting activities in vivo. Importantly, VPA, but not MNX, successfully stimulate hair growth in the wounds of C3H mice. CONCLUSIONS/ SIGNIFICANCE: Our findings indicate that small molecules that activate the Wnt/β-catenin pathway, such as VPA, can potentially be developed as drugs to stimulate hair re-growth.

  1. Neutron activation analysis of trace metals in the hair and organs of small animals treated chronically with Hg and Mn

    For the purpose of studying the secretion of exogenous toxic metals into hair, the relation between their concenrations in hair and in organs, and the metal shift Hg or Mn was orally administered to Guinea pigs for protracted periods. The distributions of metals in hair and organs were examined by means of neutron activation analysis. It was found that the administration of Hg at high dose resulted in abnormally high Hg levels in hair from the 2nd dosing week and in organs after 25 weeks of dosing, and in a reduced motor activity after 25 weeks of administration. There occurred metal shifts in hair as well. Administration of Mn at high doses, on the other hand, showed no such biological influences, although a dose-dependent increase of Mn in hair was detected with time. (author)

  2. Activation of PI3K signaling prevents aminoglycoside-induced hair cell death in the murine cochlea

    Azadeh Jadali

    2016-06-01

    Full Text Available Loss of sensory hair cells of the inner ear due to aminoglycoside exposure is a major cause of hearing loss. Using an immortalized multipotent otic progenitor (iMOP cell line, specific signaling pathways that promote otic cell survival were identified. Of the signaling pathways identified, the PI3K pathway emerged as a strong candidate for promoting hair cell survival. In aging animals, components for active PI3K signaling are present but decrease in hair cells. In this study, we determined whether activated PI3K signaling in hair cells promotes survival. To activate PI3K signaling in hair cells, we used a small molecule inhibitor of PTEN or genetically ablated PTEN using a conditional knockout animal. Hair cell survival was challenged by addition of gentamicin to cochlear cultures. Hair cells with activated PI3K signaling were more resistant to aminoglycoside-induced hair cell death. These results indicate that increased PI3K signaling in hair cells promote survival and the PI3K signaling pathway is a target for preventing aminoglycoside-induced hearing loss.

  3. Activation analysis of human hair as a tool for environmental pollution monitoring

    Recent development and uses of neutron activation techniques for human hair analyses are reviewed. The method of neutron activation analysis (NAA) appears to have the potential to be used as a tool for environmental pollution monitoring. Principally, two types of NAA procedure are in use nowadays for multi-element analyses of human scalp hair. The more common of these is the method of instrumental neutron activation analysis (INAA) consisting in a single short-term (3 to 10 hours) exposure of hair to a beam of neutrons in a nuclear reactor, followed by two measurements of gamma-ray spectra at 2 to 3 days and 3 to 4 weeks after the irradiation. The following microelements can be commonly determined by this type of activation procedure: As, Au, Br, Cu, K, La, Na, Sb, Sm, Co, Cr, Cs, Fe, Hg, Rb, Sc, Se and Zn. The other procedure involves the use of radiochemical separation techniques and is employed for quantitative determinations of elements that are not easily determined by INAA (Mo, Cd, Ni, etc.), or in cases where there is a need to achieve the lowest possible limits of analytical determination. The accuracy of NAA techniques is strongly dependent on the hair sampling and hair sample processing methods used. The analytical error of this method may vary within the range of 5 to 15%. Its applicability as a tool for monitoring the environmental pollution level is demonstrated on an example of groups of individuals living in areas differing by the degree of environmental pollution. The use of other biological materials, such as mammalian hair, for the purpose of environmental exposure monitoring is also considered. (author)

  4. A new neutron activation technique for simultaneous determination of inorganic and total mercury contents in human hair

    A simple method for simultaneous determination of inorganic and total mercury contents in human hair by neutron activation analysis (NAA) has been developed. The method is based on the selective extraction of methylmercury from hair by hydrochloric acid. Thus, the residual phase containing inorganic mercury can be determined by NAA. Further, the methylmercury contents in hair samples are easily calculated by subtracting the inorganic mercury contribution from the total Hg simultaneously given by INAA. Several reference materials of human hair, including IAEA hair RM 085 and 086, Chinese hair RMs GBW 09101 and 07601, were analyzed by this method. Our results show that the method is reliable. (author). 10 refs., 1 fig., 1 tab

  5. Multielement neutron activation analysis of human scalp hair a local population survey in the Tokyo metropolitan area

    Applying instrumental neutron activation analysis, multielement analysis of human hair was carried out to elucidate the levels of various trace element concentrations in hair of local population in the Tokyo metropolitan area. 202 hair samples were collected from the inhabitants classified by sex and five age groups. Using several combinations of irradiation time, cooling time and counting time, forty elements were quantitatively analyzed. The method of analysis for data including samples under detection limit is discussed, assuming that the frequency distribution of trace element contents in hair is log-normal. (author)

  6. Activation of β-Catenin Signaling in CD133-Positive Dermal Papilla Cells Drives Postnatal Hair Growth

    Zhou, Linli; Xu, Mingang; Yang, Yongguang; Yang, Kun; Wickett, Randall R.; Andl, Thomas; Millar, Sarah E.

    2016-01-01

    The hair follicle dermal papilla (DP) contains a unique prominin-1/CD133-positive (CD133+) cell subpopulation, which has been shown to possess hair follicle-inducing capability. By assaying for endogenous CD133 expression and performing lineage tracing using CD133-CreERT2; ZsGreen1 reporter mice, we find that CD133 is expressed in a subpopulation of DP cells during the growth phase of the murine hair cycle (anagen), but is absent at anagen onset. However, how CD133+ DP cells interact with keratinocytes to induce hair regenerative growth remains unclear. Wnt/β-catenin has long been recognized as a major signaling pathway required for hair follicle morphogenesis, development, and regeneration. Nuclear Wnt/β-catenin activity is observed in the DP during the hair growth phase. Here we show that induced expression of a stabilized form of β-catenin in CD133+ DP cells significantly accelerates spontaneous and depilation-induced hair growth. However, hair follicle regression is not affected in these mutants. Further analysis indicates that CD133+ DP-expressed β-catenin increases proliferation and differentiation of epithelial matrix keratinocytes. Upregulated Wnt/β-catenin activity in CD133+ DP cells also increases the number of proliferating DP cells in each anagen follicle. Our data demonstrate that β-catenin signaling potentiates the capability of CD133+ DP cells to promote postnatal hair growth. PMID:27472062

  7. Dosimetry of criticality accidents using activations of the blood and hair

    The radiation dose received by a person in a criticality accident can be determined with reasonable accuracy from the activity induced in the blood or in the hair. However, both of these methods require a knowledge of the neutron spectra and the exposure conditions. In this report we have compiled results from numerous criticality studies to serve as a guide for neutron dose evaluations based on blood and hair activation. A technique is described in which a combination of these blood and hair activations can be used to determine the neutron dose. This evaluation technique is independent of the person's orientation, shielding provided by walls, equipment, etc. (except for massive shielding by metals), and the neutron leakage spectra. The technique will improve the accuracy of the dose determination, especially if there is little information available on the exposure conditions. This estimate is normally accurate to within +-20 to 30%. This paper also discusses the gamma-to-neutron ratio and its use in establishing the gamma dose (if no gamma exposure data is available) or the neutron dose (if the gamma exposure is known). The use of a G-M instrument at the abdomen is discussed and curves are given to convert the G-M readings to neutron dose. A simplified counting procedure for hair activation is recommended. (author)

  8. Characterization of Rat Hair Follicle Stem Cells Selected by Vario Magnetic Activated Cell Sorting System

    Hair follicle stem cells (HfSCs) play crucial roles in hair follicle morphogenesis and hair cycling. These stem cells are self-renewable and have the multi-lineage potential to generate epidermis, sebaceous glands, and hair follicle. The separation and identification of hair follicle stem cells are important for further research in stem cell biology. In this study, we report on the successful enrichment of rat hair follicle stem cells through vario magnetic activated cell sorting (Vario MACS) and the biological characteristics of the stem cells. We chose the HfSCs positive surface markers CD34, α6-integrin and the negative marker CD71 to design four isolation strategies: positive selection with single marker of CD34, positive selection with single marker of α6-integrin, CD71 depletion followed by CD34 positive selection, and CD71 depletion followed by α6-integrin positive selection. The results of flow cytometry analysis showed that all four strategies had ideal effects. Specifically, we conducted a series of researches on HfSCs characterized by their high level of CD34, termed CD34bri cells, and low to undetectable expression of CD34, termed CD34dim cells. CD34bri cells had greater proliferative potential and higher colony-forming ability than CD34dim cells. Furthermore, CD34bri cells had some typical characteristics as progenitor cells, such as large nucleus, obvious nucleolus, large nuclear:cytoplasmic ratio and few cytoplasmic organelles. Our findings clearly demonstrated that HfSCs with high purity and viability could be successfully enriched with Vario MACS

  9. Mitochondrial aerobic respiration is activated during hair follicle stem cell differentiation, and its dysfunction retards hair regeneration

    Tang, Yan; Luo, Binping; Deng, Zhili; Wang, Ben; Liu, Fangfen; Li, Jinmao; SHI, Wei; Xie, Hongfu; Hu, Xingwang; Li, Ji

    2016-01-01

    Background. Emerging research revealed the essential role of mitochondria in regulating stem/progenitor cell differentiation of neural progenitor cells, mesenchymal stem cells and other stem cells through reactive oxygen species (ROS), Notch or other signaling pathway. Inhibition of mitochondrial protein synthesis results in hair loss upon injury. However, alteration of mitochondrial morphology and metabolic function during hair follicle stem cells (HFSCs) differentiation and how they affect ...

  10. The Rho GTPase Cdc42 regulates hair cell planar polarity and cellular patterning in the developing cochlea

    Anna Kirjavainen; Maarja Laos; Tommi Anttonen; Ulla Pirvola

    2015-01-01

    Hair cells of the organ of Corti (OC) of the cochlea exhibit distinct planar polarity, both at the tissue and cellular level. Planar polarity at tissue level is manifested as uniform orientation of the hair cell stereociliary bundles. Hair cell intrinsic polarity is defined as structural hair bundle asymmetry; positioning of the kinocilium/basal body complex at the vertex of the V-shaped bundle. Consistent with strong apical polarity, the hair cell apex displays prominent actin and microtubul...

  11. Activation of the OVOL1-OVOL2 Axis in the Hair Bulb and in Pilomatricoma.

    Ito, Takamichi; Tsuji, Gaku; Ohno, Fumitaka; Uchi, Hiroshi; Nakahara, Takeshi; Hashimoto-Hachiya, Akiko; Yoshida, Yuichi; Yamamoto, Osamu; Oda, Yoshinao; Furue, Masutaka

    2016-04-01

    OVOL1 and OVOL2, ubiquitously conserved genes encoding C2H2 zinc finger transcription factors in mammals, control epithelial cell proliferation, and differentiation, including those in skin. OVOL1 and OVOL2 expression is coordinately mediated via the Wnt signaling pathway, and OVOL1 negatively regulates OVOL2 expression in a transcriptional manner. Our previous study of OVOL1 expression in human skin revealed that OVOL1 is preferentially expressed in the inner root sheath of the hair follicle. Therefore, we hypothesized that the OVOL1-OVOL2 axis is involved in normal and neoplastic follicular differentiation. Immunohistochemical analysis showed that OVOL1 and OVOL2 were strongly expressed in a mutually exclusive manner in the cytoplasm of inner root sheath cells and matrix cells, respectively, in normal follicles. OVOL2 was also expressed in pilomatricoma, with only partial expression of OVOL1. Cultured human keratinocytes expressed OVOL1 and OVOL2 on both the mRNA and protein levels. The expression of OVOL2 was higher in keratinocytes transfected with siRNA of OVOL1. Ketoconazole, a hair growth stimulant, up-regulated the expression of OVOL1 but did not affect OVOL2 expression. These results indicated that the OVOL1-OVOL2 axis may actively contribute to cell differentiation and proliferation in the hair bulb, suggesting that the OVOL1 and OVOL2 may be therapeutic targets of hair disorders, including alopecia, and play important roles in the tumorigenesis of pilomatricoma. PMID:26873447

  12. Use of hair cortisol analysis to detect hypercortisolism during active drinking phases in alcohol-dependent individuals.

    Stalder, Tobias; Kirschbaum, Clemens; Heinze, Kareen; Steudte, Susann; Foley, Paul; Tietze, Antje; Dettenborn, Lucia

    2010-12-01

    The assessment of cortisol levels in human hair has recently been suggested to provide a retrospective index of cumulative cortisol exposure over periods of up to 6 months. The current study examined the utility of hair cortisol analysis to retrospectively detect hypercortisolism during active drinking phases in alcoholics in acute withdrawal (n=23), the normalisation of cortisol output in abstinent alcoholics (n=25) and cortisol levels in age- and gender-matched controls (n=20). Scalp-near 3-cm hair segments were sampled and analysed for cortisol content. Results showed three to fourfold higher cortisol levels in hair samples of alcoholics in acute withdrawal than in those of abstinent alcoholics (p<.001) or controls (p<.001), with no differences between the latter two groups. The current hair cortisol findings closely mirror results of previous research using well-established measures of systemic cortisol secretion and thus provide further validation of this novel method. PMID:20727937

  13. The potentials and limitations of using neutron activation analysis data on human hair as a forensic evidence

    A survey of hair samples from a group of 300 vounteers, involving nearly 12 000 elemental analyses, indicates that while neutron-activation-analysis data have distinct potentials to develop useful forensic evidence, there are several limitations to its routine applications. The multi-elemental analyses of hair-wash samples were done using multiple neutron irradiation and high resolution gamma ray spectrometry. All neutron irradiations were performed in the Penn State TRIGA Reactor at a thermal neutron flux of approximately 1013nxcm-2xs-1. The gamma-ray spectrometric measurements utilized a 40 cm3 high resolution Ge(Li) detector. This detector, in association with a software oriented programmable multichannel analyzer with a 12 K core size, was used for gamma ray spectrometric measurements. The data were recorded on computer-compatible magnetic tape. The quantitative measurements of only 22 elements were reported from both the hair samples and the ''hair-wash''. These elements are Ti, I, Br, Mn, Cu, V, Cl, Al, Na, Ca, Se, Hg, Cr, Au, Sb, Ag, Sc, Zn, Co, Fe, and La. In expressing the analytical results of ''hair-wash'' samples, the weight of hair from which the hair-wash originated was used to calculate the results in terms of the weight of hair. (T.G.)

  14. Hair Care

    ... Body Looking and feeling your best Hair care Hair care Short, long, curly, straight, up, down. Hair options can seem endless! Not all of what makes your hair look good comes from the outside, though. Good ...

  15. Oily hair

    Hair - oily ... are some tips for preventing and treating oily hair: Shampoo your hair every day. Leaving the shampoo on your head ... minutes before rinsing may help. Avoid brushing your hair too often or too vigorously, since the brushing ...

  16. Determination of mercury contents in head hair of dentists by instrumental neutron activation analysis

    Mercury contents in head hair of 32 dentists and 30 controls were determined by instrumental neutron activation analysis. The precision and accuracy of the analytical results were checked by independent analytical techniques comprising cold vapour atomic absorption spectrometry and neutron activation analysis combined with lead diethyldithiocarbamate as a preconcentrating agent. The normal range was from 1.91 to 5.44 ppm with an arithmetic mean of 3.90+-1.01 ppm, and the geometric mean of 3.76x:1.33 ppm. The range, arithmetic and geometric means of the values for dentists were 4.32-24.14 ppm, 11.68+-4.70 ppm, and 10.77x:4.04 ppm, resp. The mercury contents in the hair of the dentists are significantly higher than those of the controls. It indicates that dentists in Taiwan do not practice good mercury hygiene. However, the mercury contents are considerably below the toxicity level. (author)

  17. Cyclic dermal BMP signalling regulates stem cell activation during hair regeneration.

    Plikus, Maksim V; Mayer, Julie Ann; de la Cruz, Damon; Baker, Ruth E; Maini, Philip K; Maxson, Robert; Chuong, Cheng-Ming

    2008-01-17

    In the age of stem cell engineering it is critical to understand how stem cell activity is regulated during regeneration. Hairs are mini-organs that undergo cyclic regeneration throughout adult life, and are an important model for organ regeneration. Hair stem cells located in the follicle bulge are regulated by the surrounding microenvironment, or niche. The activation of such stem cells is cyclic, involving periodic beta-catenin activity. In the adult mouse, regeneration occurs in waves in a follicle population, implying coordination among adjacent follicles and the extrafollicular environment. Here we show that unexpected periodic expression of bone morphogenetic protein 2 (Bmp2) and Bmp4 in the dermis regulates this process. This BMP cycle is out of phase with the WNT/beta-catenin cycle, thus dividing the conventional telogen into new functional phases: one refractory and the other competent for hair regeneration, characterized by high and low BMP signalling, respectively. Overexpression of noggin, a BMP antagonist, in mouse skin resulted in a markedly shortened refractory phase and faster propagation of the regenerative wave. Transplantation of skin from this mutant onto a wild-type host showed that follicles in donor and host can affect their cycling behaviours mutually, with the outcome depending on the equilibrium of BMP activity in the dermis. Administration of BMP4 protein caused the competent region to become refractory. These results show that BMPs may be the long-sought 'chalone' inhibitors of hair growth postulated by classical experiments. Taken together, results presented in this study provide an example of hierarchical regulation of local organ stem cell homeostasis by the inter-organ macroenvironment. The expression of Bmp2 in subcutaneous adipocytes indicates physiological integration between these two thermo-regulatory organs. Our findings have practical importance for studies using mouse skin as a model for carcinogenesis, intra-cutaneous drug

  18. Determination of antimony in nail and hair by thermal neutron activation analysis

    The concentration of antimony in nail and hair was determined by thermal neutron activation analysis. Samples were collected from the workers of an antimony refinery, inhabitants near the refinery, and residents in control area. They were irradiated by Kyoto University 5000 kW Reactor for 1 h, and cooled for 30 to 100 days. After cooling, the concentration of Sb in nail and hair was estimated by measuring the intensity of γ-ray from 124Sb of the samples, then the samples were washed by 0.1 % aqueous solution of nonionic surface active agent in an ultrasonic cleaner. The γ-ray spectrometry was done again (after washing). The concentration of Sb in nail before washing was 730 ppm for the workers, 2.46 ppm for habitants near the refinery, and 0.19 ppm for the control; after washing, it became 230 ppm for the workers, 0.63 ppm for habitants, and 0.09 ppm for the control. The concentration of Sb in hair before and after washing was 222 ppm and 196 ppm for the workers, and 0.21 ppm and 0.15 ppm for the control, respectively. (author)

  19. New strict left bundle branch block criteria reflect left ventricular activation differences

    Emerek, Kasper Janus Grønn; Risum, Niels; Hjortshøj, Søren Pihlkjær;

    2015-01-01

    AIMS: Pacing lead electrical delays and strict left bundle branch block (LBBB) criteria were assessed against cardiac resynchronization therapy (CRT) outcome. METHODS: Forty-nine patients with LBBB and QRS duration >130 milliseconds underwent CRT-implantation. Sensed right ventricular to left...

  20. Hair-zinc levels determination in Algerian psoriatics using Instrumental Neutron Activation Analysis (INAA)

    Psoriasis is a multifactorial skin disease with an unknown etiology. Zinc has a positive impact on psoriasis. The aim of this study is to determine hair-zinc concentration in Algerian psoriatics. 58 psoriatics and 31 normal controls of both genders were selected. Hair zinc levels were determined using Instrumental Neutron Activation Analysis technique (INAA). Student's t-test and One-Way ANOVA were applied. The average zinc concentration for controls and patients were 152±53 μg/g and 167±52 μg/g respectively. They are not significantly different (p>0.05). Zn concentration for males and females controls and patients were 171±27 μg/g, 151±37 μg/g and 145±59 μg/g, 178±58 μg/g respectively. However, for females we have observed a significant difference (p<0.05). - Highlights: ► Psoriasis is a multifactorial skin disease with an unknown etiology. ► About 2–5% of global population in the world suffers from psoriasis. ► The aim of this study is to determine hair-zinc concentration in Algerian psoriatics. ► The average zinc concentration for controls and patients were 152±53 μg/g and 167±52 μg/g respectively.

  1. Neutron, gamma and Roentgen fluorescent activation analysis of hair of children suffering from bronchial asthma

    The aim of present study was the multiparametric study of dangerous microelements content in the hair of children under school and primary school age which included 12 children ill with bronchial asthma and 11 control group persons in the town of Troitsk, Moscow Region. The hair specimens with weight 15-220 mg were analysed with the application of epithermal neutron activation analysis conducted at experimental installation REGATA and neutron source-unique Pulsed Fast Reactor IBR-2, with the application of combined gamma-neutron irradiation at Microtron MT-25 and with Roentgen Fluorescence Analysis device of JINR. The data of elements content in hair were obtained with solid state track detectors and semiconductor electronic spectrometers. The solid state track detectors provide the determination of U, Th, Bi and Be elements at the level of sensitivity up to 10-8-10-9 g/g. These data were compared with more representative information about dangerous microelements concentration obtained with NAA and RFA analyses. The obtained concentrations of most elements vary in a wide range, but in agreement with the known data. The highest degree of element dispersion was observed for U, Th, Pb, I, Br, Sb, Co, K and Be (the radiation coefficient was higher than 100-200%). The presented analysis of results shows that in the clinical picture there is some proved correlation between an increased content of some element in hair and symptoms of their accumulation in the organism of ill children, the revelation of which is the basic idea of our examination

  2. Radioactivation analysis of hair

    With the aim of indicating environmental pollution effects by heavy metals on humans using hair, nondestructive activation analysis was applied to 382 normal Japanese hair samples (background level). Elemental contents of hair could be determined for Ag, Al, As, Br, Ca, Cd, Cl, Co, Cr, Cu, Fe, Hg, I, K, La, Mg, Mn, Na, S, Sb, Sc, Se, Sm, Ti, V and Zn. As these elements in hair have wide concentration ranges, the differences in concentration distribution between groups (sex, age, permanent treatment and regional difference) are discussed. A method for hair sampling is presented. (author)

  3. Determination of arsenic, selenium and antimony by neutron activation analysis. Application to hair samples

    A fast rabbit system for instrumental activation analysis with reactor neutrons is described. Its use in the determination of selenium in hair is discussed. A survey is given of the correction factors which are inherent to the use of short-lived radionuclides. An alternative to INAA is NAA based on the separation of arsenic, selenium and antimony by hydride evaporation and adsorption to active carbon. Data for some Standard Reference Materials are given. This work was done under research contract 2440/RI/RB with the IAEA

  4. The amazing miniorgan: Hair follicle

    Çiler Çelik Özenci

    2014-01-01

    Hair is a primary characteristic of mammals, and exerts a wide range of functions including thermoregulation, physical protection, sensory activity, and social interactions. The hair shaft consists of terminally differentiated keratinocytes that are produced by the hair follicle. Hair follicle development takes place during fetal skin development and relies on tightly regulated ectodermal–mesodermal interactions. Hair follicles form during embryonic development and, after birth, undergo recur...

  5. Interactive user's application to Genie 2000 spectroscopy system for automation of hair neutron activation analysis

    Full text: In recent years lower plants such as mosses or lichens and for arid countries bark and leaves of tree have been used as biomonitors in environmental studies. Alongside with plants the trace elemental human hair composition also has been used as an indicator of pollution of natural and industrial environments. Because of convenience, easy access, nondestruction of sampling, and also preservation of information for a long time period, human hair even more often and widely used in various researches. In the Institute of Nuclear Physics of the Academy of Sciences of the Republic of Uzbekistan hair trace element analysis in environment monitoring and mapping and in health status studies have been used. Scientist of activation analysis laboratory always has a lot of routine work on biological objects analysis, so they regularly improved applied nuclear techniques. At present one of such good work-out technique is consider a hair multielement instrumental neutron activation analysis using single comparator standard method. Since in frames of the 'Enhanced nuclear techniques for materials identification' STCU project, the Radioanalytical Center (RAC) was created in October 2004, for analysis such objects as metals and alloys, minerals and ores, hydrogeological samples, technological products, soils, fertilizers, biological samples, foodstuff, water, sediments, construction materials, as well as materials of unknown composition the unique equipment of RAC have been used. For example, human hair analysis has performed on the base of HP Ge-detector with high resolution gamma-spectrometer of Canberra Industries, Inc. Genie-2000 Spectroscopy System of Canberra spectrometers, represents the true state of the art in spectroscopy software platforms. Genie 2000 is a comprehensive set of capabilities for acquiring and analyzing spectra from Multichannel Analyzers (MCA). Its functions include MCA control, spectral display and manipulation, basic spectrum analysis and

  6. Hair transplant

    Hair restoration ... Avram MR, Keene SA, Stough DB, Rogers NE. Hair restoration. In: Bolognia JL, Jorizzo JL, Schaffer JV, eds. ... PA: Elsevier Saunders; 2012:chap 157. Fisher J. Hair restoration. In: Neligan PC, ed. Plastic Surgery . 3rd ed. ...

  7. Split-Cre complementation restores combination activity on transgene excision in hair roots of transgenic tobacco.

    Mengling Wen

    Full Text Available The Cre/loxP system is increasingly exploited for genetic manipulation of DNA in vitro and in vivo. It was previously reported that inactive ''split-Cre'' fragments could restore Cre activity in transgenic mice when overlapping co-expression was controlled by two different promoters. In this study, we analyzed recombination activities of split-Cre proteins, and found that no recombinase activity was detected in the in vitro recombination reaction in which only the N-terminal domain (NCre of split-Cre protein was expressed, whereas recombination activity was obtained when the C-terminal (CCre or both NCre and CCre fragments were supplied. We have also determined the recombination efficiency of split-Cre proteins which were co-expressed in hair roots of transgenic tobacco. No Cre recombination event was observed in hair roots of transgenic tobacco when the NCre or CCre genes were expressed alone. In contrast, an efficient recombination event was found in transgenic hairy roots co-expressing both inactive split-Cre genes. Moreover, the restored recombination efficiency of split-Cre proteins fused with the nuclear localization sequence (NLS was higher than that of intact Cre in transgenic lines. Thus, DNA recombination mediated by split-Cre proteins provides an alternative method for spatial and temporal regulation of gene expression in transgenic plants.

  8. Neutron activation analysis of mercury contents in head hair of dentists in Japan

    Mercury contents in head hair of 58 dentists employed at the NUSD hospital and 50 dentists employed at private hospitals or clinics were determined using neutron activation analysis. The arithmetic means were 5.8 ppm and 5.2 ppm, and geometric means were 5.4 ppm and 4.8 ppm, respectively. They were much lower than the values reported in the preceding year, and agreed well with those of normal Japanese persons of the same age. Therefore, it was concluded that the mercury pollution in the working environment of dentists might be practically negligible in Japan today. (author)

  9. Elemental analysis of soil and hair sample by instrumental neutron activation analysis

    Chung, Yong Sam; Quraishi, Shamshad Begum; Moon, Jong Hwa; Kim, Sun Ha; Baek, Sung Yeoil; Kang, Sang Hoon; Lim, Jong Myoung; Cho, Hyun Je; Kim, Young Jin

    2004-03-01

    Myanmar soil sample was analyzed by using the instrumental neutron activation analysis. The elemental concentrations in the sample, altogether 34 elements, Al As, Ba, Ce, Co, Cr, Cs, Eu, Fe, Ga, Gd, Hf, Ir, K, La, Lu, Mn, Na, Nd, Rb, Sb, Sc, Se, Sm, Th, Ti, V, Yb, Zn and Zr were determined. The concentration of 17 elements (Al, Au, Br, Ca, Cl, Cr, Cu, Co, Fe, Hg, K, Na, Mn, Mg, Sb, Se, Zn) in human hair samples were determined by INAA For quality control of analytical method, certified reference material was used.

  10. Elemental analysis of soil and hair sample by instrumental neutron activation analysis

    Myanmar soil sample was analyzed by using the instrumental neutron activation analysis. The elemental concentrations in the sample, altogether 34 elements, Al As, Ba, Ce, Co, Cr, Cs, Eu, Fe, Ga, Gd, Hf, Ir, K, La, Lu, Mn, Na, Nd, Rb, Sb, Sc, Se, Sm, Th, Ti, V, Yb, Zn and Zr were determined. The concentration of 17 elements (Al, Au, Br, Ca, Cl, Cr, Cu, Co, Fe, Hg, K, Na, Mn, Mg, Sb, Se, Zn) in human hair samples were determined by INAA For quality control of analytical method, certified reference material was used

  11. Hair Follicle Pigmentation

    Slominski, Andrzej; Wortsman, Jacobo; Plonka, Przemyslaw M.; Schallreuter, Karin U.; Paus, Ralf; Tobin, Desmond J.

    2005-01-01

    Hair shaft melanin components (eu- or/and pheomelanin) are a long-lived record of precise interactions in the hair follicle pigmentary unit, e.g., between follicular melanocytes, keratinocytes, and dermal papilla fibroblasts. Follicular melanogenesis (FM) involves sequentially the melanogenic activity of follicular melanocytes, the transfer of melanin granules into cortical and medulla keratinocytes, and the formation of pigmented hair shafts. This activity is in turn regulated by an array of...

  12. Effect of Tectona grandis Linn. seeds on hair growth activity of albino mice

    Jaybhaye, Deepali; Varma, Sushikumar; Gagne, Nitin; bonde, Vijay; Gite, Amol; Bhosle, Deepak

    2010-01-01

    The seeds of Tectona grandis Linn. are traditionally acclaimed as hair tonic in the Indian system of medicine. Studies were therefore undertaken in order to evaluate petroleum ether extract of T. grandis seeds for its effect on hair growth in albino mice. The 5% and 10% extracts incorporated into simple ointment base were applied topically on shaved denuded skin of albino mice. The time required for initiation of hair growth as well as completion of hair growth cycle was recorded. Minoxidil 2...

  13. Hair Dye and Hair Relaxers

    ... Consumers Consumer Information by Audience For Women Hair Dye and Hair Relaxers Share Tweet Linkedin Pin it More sharing ... products. If you have a bad reaction to hair dyes and relaxers, you should: Stop using the product. ...

  14. STAT5 Activation in the Dermal Papilla Is Important for Hair Follicle Growth Phase Induction.

    Legrand, Julien M D; Roy, Edwige; Ellis, Jonathan J; Francois, Mathias; Brooks, Andrew J; Khosrotehrani, Kiarash

    2016-09-01

    Hair follicles are skin appendages that undergo periods of growth (anagen), regression (catagen), and rest (telogen) regulated by their mesenchymal component, the dermal papilla (DP). On the basis of the reports of its specific expression in the DP, we investigated signal transducer and activator of transcription (STAT5) activation during hair development and cycling. STAT5 activation in the DP began in late catagen, reaching a peak in early anagen before disappearing for the rest of the cycle. This was confirmed by the expression profile of suppressor of cytokine signaling 2, a STAT5 target in the DP. This pattern of expression starts after the first postnatal hair cycle. Quantification of hair cycling using the Flash canonical Wnt signaling in vivo bioluminescence reporter found that conditional knockout of STAT5A/B in the DP targeted through Cre-recombinase under the control of the Sox18 promoter resulted in delayed anagen entry compared with control. Microarray analysis of STAT5 deletion versus control revealed key changes in tumor necrosis factor-α, Wnt, and fibroblast growth factor ligands, known for their role in inducing anagen entry. We conclude that STAT5 activation acts as a mesenchymal switch to trigger natural anagen entry in postdevelopmental hair follicle cycling. PMID:27131881

  15. Multielement analysis of human hair reference material by instrumental neutron activation analysis

    A Human Hair (NIES No. 5) as an environmental reference material prepared by the National Institute for Environmental Studies of Japan (NIES) was analyzed by an instrumental neutron activation method. The human hair samples (ca. 200∼500 mg) were irradiated for 2 min or 5 h at Musashi Institute of Technology Research Reactor. The activated samples were measured by four gamma-ray spectrometories, namely a spectrometry using a coaxial Ge detector, anticoincidence and coincidence counting spectrometries using a coaxial Ge detector, and a well-type NaI (Tl) detector, and a low energy photon spectrometry (LEPS) using a planer Ge detector, to determine as many trace elements as possible with high sensitivity. Concentrations of 43 elements (Na, Mg, Al, Si, S, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Ag, Cd, Sn, Sb, I, Cs, Ba, La, Ce, Nd, Sm, Eu, Tb, Yb, Hf, Ta, Au, Hg, Th, U) were determined by these measurements. The analyzed values of many elements except Sr were in good agreement with NIES certified values determined by nine different analytical methods. (author)

  16. Bundling biodiversity

    Heal, Geoffrey

    2002-01-01

    Biodiversity provides essential services to human societies. Many of these services are provided as public goods, so that they will typically be underprovided both by market mechanisms (because of the impossibility of excluding non-payers from using the services) and by government-run systems (because of the free rider problem). I suggest here that in some cases the public goods provided by biodiversity conservation can be bundled with private goods and their value to consumers captured in th...

  17. Hair cell ribbon synapses

    Moser, Tobias; Brandt, Andreas; Lysakowski, Anna

    2006-01-01

    Hearing and balance rely on the faithful synaptic coding of mechanical input by the auditory and vestibular hair cells of the inner ear. Mechanical deflection of their stereocilia causes the opening of mechanosensitive channels, resulting in hair cell depolarization, which controls the release of glutamate at ribbon-type synapses. Hair cells have a compact shape with strong polarity. Mechanoelectrical transduction and active membrane turnover associated with stereociliar renewal dominate the ...

  18. Hair transplantation.

    Avram, Marc R

    2012-12-01

    Hair transplantation is a purely dermatologic surgical procedure that dermatologists should be able to perform in appropriate candidates with hair loss. Hair transplantation techniques performed in the 1960s through the 1990s utilized large grafts that created an unfortunate public image of unnatural-appearing transplanted hair. Over the last 15 years, hair transplantation has been performed using follicular units to create consistently natural-looking transplanted hair in both men and women. This article provides an overview of candidate selection and state-of-the-art techniques for performing hair transplantation. PMID:23409484

  19. Self-Organization in Active Cytoskeletal Mixtures: Cilia-like Beating of Microtubule Bundles and Spontaneous Bulk Mixing

    Sanchez, Tim

    This thesis discusses circularization and supercoiling of actin biofilaments, as well as the various examples of self-organization observed in a simple non-equilibrium system of microtubules, motor clusters, and a depletion agent (PEG). When the ends of an actin filament approach each other, annealing can occur, resulting in the assumption of a circular conformation. In order to facilitate this experimentally, we dramatically reduce the space available for the ends to explore by confining the filaments to a quasi-2D region. This is accomplished through the use of a depletion attraction. In addition to the pronounced effects of this topological ring constraint on the statistical fluctuations of the filaments, we also observe a spontaneous supercoiling transition in fluorescently labeled actin rings that is directly driven by illumination. To better understand this transition in natural twist, we investigate real-time twist of a filament trapped between two beads, held by optical traps. The main focus of this graduate work was on the behavior of non-equilibrium in vitro mixtures of microtubules, kinesin motor clusters, and a depletion agent. We observed several striking and distinct examples of self-organization on near-macroscopic length scales, due to the interactions of very simple components. First we investigate the driving mechanism behind the beating of biological cilia and flagella, and find that this beating functionality can be reproduced in our vastly simpler system. This occurs only when minimalist components are reconstituted: motors, biofilaments, elastic links to hold the filaments together, and a basal attachment. Beyond the cooperativity of the motors to produce oscillatory beating in individual bundles, we also observe that active bundles in close proximity can synchronize their beating to produce stable, periodic metachronal waves that propagate along the bundle array. By changing only the length distribution of the microtubules in our system, we

  20. The preshaving protocol in body hair-to-scalp transplant to identify hair in anagen phase

    Poswal Arvind

    2010-01-01

    Full Text Available Introduction: The use of body donor hair for transplanting to the bald scalp is termed body hair transplant. In recent times, robust body hair has been used as an adjunct to scalp donor hair to augment the donor hair supply. A large percentage of body hair are in telogen and, as single hair units. Aims: To devise a non invasive protocol to identify the body donor hair in anagen phase prior to extraction. Materials and Methods: Hairs are shaved flush with the skin, four days prior to extraction. On fourth day, the actively growing hair follicles as well as non growing hairs were extracted and phase of hair growth determined. Results: Nineteen out 22 extracted hair follicles in nongrowing phase were found to be the telogen phase. Conclusion: Preshaving the body donor areas is a simple non invasive method of isolating the hair in anagen phase.

  1. Premature graying of hair

    Deepika Pandhi

    2013-01-01

    Full Text Available Premature graying is an important cause of low self-esteem, often interfering with socio-cultural adjustment. The onset and progression of graying or canities correlate very closely with chronological aging, and occur in varying degrees in all individuals eventually, regardless of gender or race. Premature canities may occur alone as an autosomal dominant condition or in association with various autoimmune or premature aging syndromes. It needs to be differentiated from various genetic hypomelanotic hair disorders. Reduction in melanogenically active melanocytes in the hair bulb of gray anagen hair follicles with resultant pigment loss is central to the pathogenesis of graying. Defective melanosomal transfers to cortical keratinocytes and melanin incontinence due to melanocyte degeneration are also believed to contribute to this. The white color of canities is an optical effect; the reflection of incident light masks the intrinsic pale yellow color of hair keratin. Full range of color from normal to white can be seen both along individual hair and from hair to hair, and admixture of pigmented and white hair is believed to give the appearance of gray. Graying of hair is usually progressive and permanent, but there are occasional reports of spontaneous repigmentation of gray hair. Studies evaluating the association of canities with osteopenia and cardiovascular disease have revealed mixed results. Despite the extensive molecular research being carried out to understand the pathogenesis of canities, there is paucity of effective evidence-based treatment options. Reports of repigmentation of previously white hair following certain inflammatory processes and use of drugs have suggested the possibility of cytokine-induced recruitment of outer sheath melanocytes to the hair bulb and rekindled the hope for finding an effective drug for treatment of premature canities. In the end, camouflage techniques using hair colorants are outlined.

  2. The Growth of Human Hair.

    Jones, Helen J.

    1984-01-01

    Suggests a simple technique for collecting and observing human hair roots to compare structure, function, and variation. Students extract their own hair samples and view them using a 40-power microscope objective. Differences between active/inactive phases of hair growth are readily observed. (The activity can be adapted for younger students.) (DH)

  3. 6-Gingerol Inhibits Hair Shaft Growth in Cultured Human Hair Follicles and Modulates Hair Growth in Mice

    Miao, Yong; Sun, Yabin; Wang, Wenjun; Du, Benjun; Xiao, Shun-e; Hu, Yijue; Hu, Zhiqi

    2013-01-01

    Ginger (Zingiber officinale) has been traditionally used to check hair loss and stimulate hair growth in East Asia. Several companies produce shampoo containing an extract of ginger claimed to have anti-hair loss and hair growth promotion properties. However, there is no scientific evidence to back up these claims. This study was undertaken to measure 6-gingerol, the main active component of ginger, on hair shaft elongation in vitro and hair growth in vivo, and to investigate its effect on hu...

  4. Trace element determination in fingernails, hair and blood serum in patients with Crohn's disease using neutron activation analysis

    The determination of trace elements and electrolyte concentrations in blood serum, hair and fingernails of 16 patients with Crohn's disease was carried out by means of instrumental neutron activation analysis. In the serum a significant decline in the zinc content could be registered, while the remaining trace elements remained in the normal range. The parenteral nutrition also showed a zinc deficiency. There was, however, also an iron deficiency. The studies of the hair and fingernails gave the following results: Rubidium and antimony in the normal range; zinc, selenium, iron and cobalt below normal values. (orig./PW)

  5. Comparative Transduction Mechanisms of Vestibular Otolith Hair Cells

    Baird, Richard A.

    1994-01-01

    Hair cells in the bullfrog vestibular otolith organs regenerate following aminoglycoside ototoxicity. Hair cells in these organs are differentially sensitive to gentamicin, with saccular hair cells and hair cells in the utricular striola being damaged at lower gentamicin concentrations than hair cells in the utricular extrastriola. Regenerating hair cells in these organs have short hair bundles and can be classified into a number of phenotypes using the same morphological criteria used to identify their mature counterparts. Our studies suggest that some supporting cells can convert, or transdifferentiate,into hair cells without an intervening cell division. By stimulating these processes in humans, clinicians may be able to alleviate human deafness and peripheral vestibular disorders by regenerating and replacing lost hair cells. In vivo and in vitro studies were done on cell proliferation and hair cell regeneration.

  6. Determination of As by instrumental neutron activation analysis in sectioned hair samples for forensic purposes: chronic or acute poisoning?

    Kučera, Jan; Kofronova, K.

    2011-01-01

    Roč. 287, č. 3 (2011), s. 769-772. ISSN 0236-5731 Institutional research plan: CEZ:AV0Z10480505 Keywords : Instrumental neutron activation analysis * Hair * Arsenic poisoning Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.520, year: 2011

  7. Left bundle-branch block

    Risum, Niels; Strauss, David; Sogaard, Peter;

    2013-01-01

    The relationship between myocardial electrical activation by electrocardiogram (ECG) and mechanical contraction by echocardiography in left bundle-branch block (LBBB) has never been clearly demonstrated. New strict criteria for LBBB based on a fundamental understanding of physiology have recently...

  8. Neutron activation analysis of trace elements in human hair by using a research reactor

    Recently, hair has been used for diagnosis of various diseases as well as blood and urine since hair is one of excretory tissues for various elements in humans. Many elements are excreted in hairs at higher concentrations than those in blood and urine. Therefore, it seems possible to estimate the effects of radiation exposure in the past. Here, the levels of elements in hairs were determined by radiation analysis using nuclear reactor. When mercury level was compared among the hairs from various countries of the world, the levels of Japanese and English were 4 ppm or more, significantly higher than around 2 ppm for the subjects in other countries. The levels were higher in cities than in the suburbs in any country, indicating that the differences might be due to air pollution. Furthermore, it was found that radioactive levels of some elements in hair were dependent on sex, especially for Ca, Cu etc. and on preexposure to a perm for Br, Ca, Mg etc. In addition, neutron analysis was indicated to be available for diagnosis of some diseases; the aluminum concentration in hairs was significantly lower in the patients with Alzheimer's disease than those with cerebrovascular diseases and the control subjects. The levels of As, Co, Cd and Hg in hairs were demonstrated to be several hundred fold higher in a woman named Otaki who died in nearly 1829 than those levels of the modern Japanese women, showing that various toxic materials such as cosmetics were used in those days. (M.N.)

  9. Fuel bundle

    This patent describes a method of forming a fuel bundle of a nuclear reactor. The method consists of positioning the fuel rods in the bottom plate, positioning the tie rod in the bottom plate with the key passed through the receptacle to the underside of the bottom plate and, after the tie rod is so positioned, turning the tie rod so that the key is in engagement with the underside of the bottom plate. Thereafter mounting the top plate is mounted in engagement with the fuel rods with the upper end of the tie rod extending through the opening in the top plate and extending above the top plate, and the tie rod is secured to the upper side of sid top plate thus simultaneously securing the key to the underside of the bottom plate

  10. Consumer available permanent hair dye products cause major allergic immune activation in an animal model

    Bonefeld, Charlotte Menne; Larsen, Jeppe Madura; Dabelsteen, Sally;

    2010-01-01

    Summary Background p-Phenylenediamine (PPD) and related substances are ingredients of more than two-thirds of oxidative (permanent) hair dyes currently used. Although PPD is a potent skin sensitizer in predictive assays, the extent to which permanent hair dyes sensitize humans has been questioned...... due to the in-use conditions, e.g. the presence of couplers in the hair dye gel and rapid oxidation using a developer. Objectives To study the skin sensitizing potential of permanent hair dyes in mice. Methods Two different permanent hair dye products containing PPD were studied in CBA mice using a...... modified version of the local lymph node assay. The colour gel and developer (oxidant) were tested separately and in combination. Response was measured by ear swelling and cytokine production in ear tissue and serum by enzyme-linked immunosorbent assay. The immune cellular response in the draining lymph...

  11. Hair Transplants

    ... Sweating Facial Redness Frown Lines and Forehead Furrows Hair Loss Sagging Skin Scars Skin Growths Skin Lesions Spider ... Sweating Facial Redness Frown Lines and Forehead Furrows Hair Loss Sagging Skin Scars Skin Growths Skin Lesions Spider ...

  12. Hair removal

    Haedersdal, Merete; Haak, Christina S

    2011-01-01

    suitable for targeting follicular and hair shaft melanin: normal mode ruby laser (694 nm), normal mode alexandrite laser (755 nm), pulsed diode lasers (800, 810 nm), long-pulse Nd:YAG laser (1,064 nm), and intense pulsed light (IPL) sources (590-1,200 nm). The ideal patient has thick dark terminal hair......Hair removal with optical devices has become a popular mainstream treatment that today is considered the most efficient method for the reduction of unwanted hair. Photothermal destruction of hair follicles constitutes the fundamental concept of hair removal with red and near-infrared wavelengths......, white skin, and a normal hormonal status. Currently, no method of lifelong permanent hair eradication is available, and it is important that patients have realistic expectations. Substantial evidence has been found for short-term hair removal efficacy of up to 6 months after treatment with the available...

  13. Hair Removal

    Hædersdal, Merete

    2011-01-01

    suitable for targeting follicular and hair shaft melanin: normal mode ruby laser (694 nm), normal mode alexandrite laser (755 nm), pulsed diode lasers (800, 810 nm), long-pulse Nd:YAG laser (1,064 nm), and intense pulsed light (IPL) sources (590-1,200 nm). The ideal patient has thick dark terminal hair......Hair removal with optical devices has become a popular mainstream treatment that today is considered the most efficient method for the reduction of unwanted hair. Photothermal destruction of hair follicles constitutes the fundamental concept of hair removal with red and near-infrared wavelengths......, white skin, and a normal hormonal status. Currently, no method of lifelong permanent hair eradication is available, and it is important that patients have realistic expectations. Substantial evidence has been found for short-term hair removal efficacy of up to 6 months after treatment with the available...

  14. Hair Removal

    ... that's also found in your fingernails and toenails. Hair growth begins beneath the surface of your skin at ... provide cushioning and protection. In some cases, excess hair growth, called hirsutism (pronounced: hur -soo-tih-zum), may ...

  15. Hair cosmetics

    Nina Madnani; Kaleem Khan

    2013-01-01

    The hair cosmetic industry has undergone a revolutionary change over the last two decades. The focus has dramatically veered from merely cleaning to repair, increasing the tensile strength, reducing oxidative damage, and stimulating growth. Newer shorter procedures to make hair look naturally more lustrous, smooth, and manageable have evolved. Specialized grooming products have been formulated to cleanse, calm, and condition the hair, and are tailored for different hair-types, for example, dr...

  16. mTOR signaling promotes stem cell activation via counterbalancing BMP-mediated suppression during hair regeneration.

    Deng, Zhili; Lei, Xiaohua; Zhang, Xudong; Zhang, Huishan; Liu, Shuang; Chen, Qi; Hu, Huimin; Wang, Xinyue; Ning, Lina; Cao, Yujing; Zhao, Tongbiao; Zhou, Jiaxi; Chen, Ting; Duan, Enkui

    2015-02-01

    Hair follicles (HFs) undergo cycles of degeneration (catagen), rest (telogen), and regeneration (anagen) phases. Anagen begins when the hair follicle stem cells (HFSCs) obtain sufficient activation cues to overcome suppressive signals, mainly the BMP pathway, from their niche cells. Here, we unveil that mTOR complex 1 (mTORC1) signaling is activated in HFSCs, which coincides with the HFSC activation at the telogen-to-anagen transition. By using both an inducible conditional gene targeting strategy and a pharmacological inhibition method to ablate or inhibit mTOR signaling in adult skin epithelium before anagen initiation, we demonstrate that HFs that cannot respond to mTOR signaling display significantly delayed HFSC activation and extended telogen. Unexpectedly, BMP signaling activity is dramatically prolonged in mTOR signaling-deficient HFs. Through both gain- and loss-of-function studies in vitro, we show that mTORC1 signaling negatively affects BMP signaling, which serves as a main mechanism whereby mTORC1 signaling facilitates HFSC activation. Indeed, in vivo suppression of BMP by its antagonist Noggin rescues the HFSC activation defect in mTORC1-null skin. Our findings reveal a critical role for mTOR signaling in regulating stem cell activation through counterbalancing BMP-mediated repression during hair regeneration. PMID:25609845

  17. Hair cosmetics

    Nina Madnani

    2013-01-01

    Full Text Available The hair cosmetic industry has undergone a revolutionary change over the last two decades. The focus has dramatically veered from merely cleaning to repair, increasing the tensile strength, reducing oxidative damage, and stimulating growth. Newer shorter procedures to make hair look naturally more lustrous, smooth, and manageable have evolved. Specialized grooming products have been formulated to cleanse, calm, and condition the hair, and are tailored for different hair-types, for example, dry, dry-damaged, oily, colored, and gray hair. Other products are formulated to alter the color or structure of the hair shaft, for example, hair dyes, perming/relaxing. Hair sprays and waxes/gels, can alter the ′lift′ of the hair-shaft. Although dermatologists are experts in managing scalp and hair diseases, the esthetic applications of newer cosmetic therapies still remain elusive. This article attempts to fill the lacunae in our knowledge of hair cosmetics and esthetic procedures relevant in today′s rapidly changing beauty-enhancing industry, with special emphasis on the Indian scenario for chemical and ′natural′ hair products.

  18. Trace element determination study in human hair by neutron activation analysis; Estudo da determinacao de elementos traco em cabelos humanos pelo metodo de analise por ativacao com neutrons

    Frazao, Selma Violato

    2008-07-01

    Human hair analysis studies have been subject of continuous interest due to the fact that they can be used as an important tool to evaluate trace element levels in the human body. These determinations have been carried out to use hair for environmental and occupational monitoring, to identify intoxication or poisoning by toxic metals, to assess nutritional status, to diagnose and to prevent diseases and in forensic sciences. Although hair analysis presents several advantages over other human tissue or fluid analyses, such as organ tissue, blood, urine and saliva, there are some controversies regarding the use of hair analysis data. These controversies arise from the fact that it is difficult to establish reliable reference values for trace elements in hair. The purpose of this study was to evaluate the factors that affect element concentrations in hair samples from a population considered healthy and residing in the Sao Paulo metropolitan area. The collected human head hair was cut in small pieces, washed, dried and analyzed by neutron activation analysis (NAA). Aliquots of hair samples and synthetic elemental standards were irradiated at the IEA-R1 nuclear research reactor for 16 h under a thermal neutron flux of about 5x10{sup 12} n cm{sup -2} s{sup -1} for As, Br, Ca, Co, Cr, Cs, Cu, Fe, K, La, Na, Sb, Sc, Se and Zn determinations. The induced gamma activities of the standards and samples were measured using a gamma ray spectrometer coupled to an hiperpure Ge detector. For quality control of the results, IAEA- 85 Human Hair and INCT-TL-1 Tea Leaves certified reference materials (CRMs) were analyzed. Results obtained in these CRMs presented for most of elements, good agreement with the values of the certificates (relative errors less than 10%) and good precision (variation coefficients less than 13.6%). Results of replicate hair sample analysis showed good reproducibility indicating homogeneity of the prepared sample. Results obtained in the analyses of dyed and

  19. Hair Mercury Negatively Correlates with Calcium Pump Activity in Human Term Newborns and Their Mothers at Delivery

    Huel, Guy; Sahuquillo, Josiane; Debotte, Ginette; Oury, Jean-François; Takser, Larissa

    2007-01-01

    Background Calcium homeostasis is a known target of several environmental toxicants including lead and mercury. Objective Our goal was to determine the relationship between Hg exposure and erythrocyte Ca pump activity in women at delivery and in their newborns. Methods We determined total Hg as well as Pb concentrations in 81 hair and blood samples obtained at delivery. Basal and calmodulin-stimulated Ca pump activity was measured in red blood cells from cord blood and maternal erythrocyte pl...

  20. New activators and inhibitors in the hair cycle clock: targeting stem cells' state of competence.

    Plikus, Maksim V

    2012-05-01

    The timing mechanism of the hair cycle remains poorly understood. However, it has become increasingly clear that the telogen-to-anagen transition is controlled jointly by at least the bone morphogenic protein (BMP), WNT, fibroblast growth factor (FGF), and transforming growth factor (TGF)-β signaling pathways. New research shows that Fgf18 signaling in hair follicle stem cells synergizes BMP-mediated refractivity, whereas Tgf-β2 signaling counterbalances it. Loss of Fgf18 signaling markedly accelerates anagen initiation, whereas loss of Tgf-β2 signaling significantly delays it, supporting key roles for these pathways in hair cycle timekeeping. PMID:22499035

  1. Inhibition of nitrogen-fixing activity of the cyanobiont affects the localization of glutamine synthetase in hair cells of Azolla.

    Uheda, Eiji; Maejima, Kazuhiro

    2009-10-15

    In the Azolla-Anabaena association, the host plant Azolla efficiently incorporates and assimilates ammonium ions that are released from the nitrogen-fixing cyanobiont, probably via glutamine synthetase (GS; EC 6.3.1.2) in hair cells, which are specialized cells protruding into the leaf cavity. In order to clarify the regulatory mechanism underlying ammonium assimilation in the Azolla-Anabaena association, Azolla plants were grown under an argon environment (Ar), in which the nitrogen-fixing activity of the cyanobiont was inhibited specifically and completely. The localization of GS in hair cells was determined by immunoelectron microscopy and quantitative analysis of immunogold labeling. Azolla plants grew healthily under Ar when nitrogen sources, such as NO(3)(-) and NH(4)(+), were provided in the growth medium. Both the number of cyanobacterial cells per leaf and the heterocyst frequency of the plants under Ar were similar to those of plants in a nitrogen environment (N(2)). In hair cells of plants grown under Ar, regardless of the type of nitrogen source provided, only weak labeling of GS was observed in the cytoplasm and in chloroplasts. In contrast, in hair cells of plants grown under N(2), abundant labeling of GS was observed in both sites. These findings indicate that specific inhibition of the nitrogen-fixing activity of the cyanobiont affects the localization of GS isoenzymes. Ammonium fixed and released by the cyanobiont could stimulate GS synthesis in hair cells. Simultaneously, the abundant GS, probably GS1, in these cells, could assimilate ammonium rapidly. PMID:19464754

  2. Lis1 mediates planar polarity of auditory hair cells through regulation of microtubule organization

    Sipe, Conor W.; Liu, Lixia; Lee, Jianyi; Grimsley-Myers, Cynthia; Lu, Xiaowei

    2013-01-01

    The V-shaped hair bundles atop auditory hair cells and their uniform orientation are manifestations of epithelial planar cell polarity (PCP) required for proper perception of sound. PCP is regulated at the tissue level by a conserved core Wnt/PCP pathway. However, the hair cell-intrinsic polarity machinery is poorly understood. Recent findings implicate hair cell microtubules in planar polarization of hair cells. To elucidate the microtubule-mediated polarity pathway, we analyzed Lis1 functio...

  3. New activators and inhibitors in the hair cycle clock: targeting stem cells’ state of competence

    Plikus, Maksim V.

    2012-01-01

    The timing mechanism of the hair cycle remains poorly understood. However, it has become increasingly clear that the telogen-to-anagen transition is controlled jointly by at least the bone morphogenic protein (BMP), WNT, fibroblast growth factor (FGF), and transforming growth factor (TGF)-β signaling pathways. New research shows that Fgf18 signaling in hair follicle stem cells synergizes BMP-mediated refractivity, whereas Tgf-β2 signaling counterbalances it. Loss of Fgf18 signaling markedly a...

  4. Hair Dyes Resorcinol and Lawsone Reduce Production of Melanin in Melanoma Cells by Tyrosinase Activity Inhibition and Decreasing Tyrosinase and Microphthalmia-Associated Transcription Factor (MITF) Expression

    Lee, Shu-Mei; Chen, Yi-Shyan; Lin, Chih-Chien; Chen, Kuan-Hung

    2015-01-01

    Hair coloring products are one of the most important cosmetics for modern people; there are three major types of hair dyes, including the temporary, semi-permanent and permanent hair dyes. The selected hair dyes (such as ammonium persulfate, sodium persulfate, resorcinol and lawsone) are the important components for hair coloring products. Therefore, we analyzed the effects of these compounds on melanogenesis in B16-F10 melanoma cells. The results proved that hair dyes resorcinol and lawsone can reduce the production of melanin. The results also confirmed that resorcinol and lawsone inhibit mushroom and cellular tyrosinase activities in vitro. Resorcinol and lawsone can also downregulate the protein levels of tyrosinase and microphthalmia-associated transcription factor (MITF) in B16-F10 cells. Thus, we suggest that frequent use of hair dyes may have the risk of reducing natural melanin production in hair follicles. Moreover, resorcinol and lawsone may also be used as hypopigmenting agents to food, agricultural and cosmetic industry in the future. PMID:25584612

  5. Hair Dyes Resorcinol and Lawsone Reduce Production of Melanin in Melanoma Cells by Tyrosinase Activity Inhibition and Decreasing Tyrosinase and Microphthalmia-Associated Transcription Factor (MITF Expression

    Shu-Mei Lee

    2015-01-01

    Full Text Available Hair coloring products are one of the most important cosmetics for modern people; there are three major types of hair dyes, including the temporary, semi-permanent and permanent hair dyes. The selected hair dyes (such as ammonium persulfate, sodium persulfate, resorcinol and lawsone are the important components for hair coloring products. Therefore, we analyzed the effects of these compounds on melanogenesis in B16-F10 melanoma cells. The results proved that hair dyes resorcinol and lawsone can reduce the production of melanin. The results also confirmed that resorcinol and lawsone inhibit mushroom and cellular tyrosinase activities in vitro. Resorcinol and lawsone can also downregulate the protein levels of tyrosinase and microphthalmia-associated transcription factor (MITF in B16-F10 cells. Thus, we suggest that frequent use of hair dyes may have the risk of reducing natural melanin production in hair follicles. Moreover, resorcinol and lawsone may also be used as hypopigmenting agents to food, agricultural and cosmetic industry in the future.

  6. Hair dyes resorcinol and lawsone reduce production of melanin in melanoma cells by tyrosinase activity inhibition and decreasing tyrosinase and microphthalmia-associated transcription factor (MITF) expression.

    Lee, Shu-Mei; Chen, Yi-Shyan; Lin, Chih-Chien; Chen, Kuan-Hung

    2015-01-01

    Hair coloring products are one of the most important cosmetics for modern people; there are three major types of hair dyes, including the temporary, semi-permanent and permanent hair dyes. The selected hair dyes (such as ammonium persulfate, sodium persulfate, resorcinol and lawsone) are the important components for hair coloring products. Therefore, we analyzed the effects of these compounds on melanogenesis in B16-F10 melanoma cells. The results proved that hair dyes resorcinol and lawsone can reduce the production of melanin. The results also confirmed that resorcinol and lawsone inhibit mushroom and cellular tyrosinase activities in vitro. Resorcinol and lawsone can also downregulate the protein levels of tyrosinase and microphthalmia-associated transcription factor (MITF) in B16-F10 cells. Thus, we suggest that frequent use of hair dyes may have the risk of reducing natural melanin production in hair follicles. Moreover, resorcinol and lawsone may also be used as hypopigmenting agents to food, agricultural and cosmetic industry in the future. PMID:25584612

  7. MicroRNA-214 controls skin and hair follicle development by modulating the activity of the Wnt pathway.

    Ahmed, Mohammed I; Alam, Majid; Emelianov, Vladimir U; Poterlowicz, Krzysztof; Patel, Ankit; Sharov, Andrey A; Mardaryev, Andrei N; Botchkareva, Natalia V

    2014-11-24

    Skin development is governed by complex programs of gene activation and silencing, including microRNA-dependent modulation of gene expression. Here, we show that miR-214 regulates skin morphogenesis and hair follicle (HF) cycling by targeting β-catenin, a key component of the Wnt signaling pathway. miR-214 exhibits differential expression patterns in the skin epithelium, and its inducible overexpression in keratinocytes inhibited proliferation, which resulted in formation of fewer HFs with decreased hair bulb size and thinner hair production. The inhibitory effects of miR-214 on HF development and cycling were associated with altered activities of multiple signaling pathways, including decreased expression of key Wnt signaling mediators β-catenin and Lef-1, and were rescued by treatment with pharmacological Wnt activators. Finally, we identify β-catenin as one of the conserved miR-214 targets in keratinocytes. These data provide an important foundation for further analyses of miR-214 as a key regulator of Wnt pathway activity and stem cell functions during normal tissue homeostasis, regeneration, and aging. PMID:25422376

  8. MicroRNA-214 controls skin and hair follicle development by modulating the activity of the Wnt pathway

    Ahmed, Mohammed I.; Alam, Majid; Emelianov, Vladimir U.; Poterlowicz, Krzysztof; Patel, Ankit; Sharov, Andrey A.; Mardaryev, Andrei N.; Botchkareva, Natalia V.

    2014-01-01

    Skin development is governed by complex programs of gene activation and silencing, including microRNA-dependent modulation of gene expression. Here, we show that miR-214 regulates skin morphogenesis and hair follicle (HF) cycling by targeting β-catenin, a key component of the Wnt signaling pathway. miR-214 exhibits differential expression patterns in the skin epithelium, and its inducible overexpression in keratinocytes inhibited proliferation, which resulted in formation of fewer HFs with de...

  9. Death mode-dependent reduction in succinate dehydrogenase activity in hair cells of aging rat cochleae

    YANG Wei-ping; HU Bo-hua; SUN Jian-he; ZHAI Suo-qiang; Donald Henderson

    2010-01-01

    Background Our previous studies have shown that both apoptosis and necrosis are involved in hair cell (HC) pathogenesis in aging cochleae. To better understand the biological mechanisms responsible for the regulation of HC death, we examined the activity of succinate dehydrogenase (SDH), a mitochondrial bioenergetic enzyme, in the HCs of aging cochleae.Methods The auditory brainstem response thresholds elicited by tone bursts at 4, 10 and 20 kHz were measured in both young (2-3 months) and aging (22-23 months) Wistar rats. SDH activity was evaluated with a colorimetric assay using nitroblue tetrazolium monosodium salt. The SDH-labeled organs of Corti were double stained with propidium iodide, a DNA intercalating fluorescent probe for illustration of HC nuclei. All the specimens were examined with fluorescence microscopy and confocal microscopy.Results Aging rats exhibited a significant elevation of ABR thresholds with threshold shifts being 34 dB at 20 kHz, 28 dB at 10 kHz, and 25 dB at 4 kHz. Consistent with the reduction in the cochlear function, aging cochleae exhibited the reduction of SDH staining intensity in the apical and the basal ends of the cochleae, where a large number of apoptotic, necrotic, and missing HCs were evident. The reduction in SDH staining appeared in a cell-death-mode dependent fashion. Specifically, SDH labeling remained in apoptotic HCs. In contrast, SDH staining was markedly reduced or absent in necrotic HCs.Conclusions In the aging cochlea, SDH activity is preserved in HCs undergoing apoptosis, but is substantially reduced in necrosis. These results suggest that mitochondrial energetic function is involved in the regulation of cell death pathways in the pathogenesis of aging cochleae.

  10. Hair casts

    Sweta S Parmar

    2014-01-01

    Full Text Available Hair casts or pseudonits are circumferential concretions,which cover the hair shaft in such a way that, it could be easily removed. They are thin, cylindrical, and elongated in length. We present an unusual case of an 8-year-old girl presenting with hair casts. Occurrence of these is unusual, and they may have varied associations. This patient was suffering from developmental delay. It is commonly misdiagnosed as and very important to differentiate from pediculosis capitis.

  11. Electron transfer activity of a de novo designed copper center in a three-helix bundle fold.

    Plegaria, Jefferson S; Herrero, Christian; Quaranta, Annamaria; Pecoraro, Vincent L

    2016-05-01

    In this work, we characterized the intermolecular electron transfer (ET) properties of a de novo designed metallopeptide using laser-flash photolysis. α3D-CH3 is three helix bundle peptide that was designed to contain a copper ET site that is found in the β-barrel fold of native cupredoxins. The ET activity of Cuα3D-CH3 was determined using five different photosensitizers. By exhibiting a complete depletion of the photo-oxidant and the successive formation of a Cu(II) species at 400nm, the transient and generated spectra demonstrated an ET transfer reaction between the photo-oxidant and Cu(I)α3D-CH3. This observation illustrated our success in integrating an ET center within a de novo designed scaffold. From the kinetic traces at 400nm, first-order and bimolecular rate constants of 10(5)s(-1) and 10(8)M(-1)s(-1) were derived. Moreover, a Marcus equation analysis on the rate versus driving force study produced a reorganization energy of 1.1eV, demonstrating that the helical fold of α3D requires further structural optimization to efficiently perform ET. This article is part of a Special Issue entitled Biodesign for Bioenergetics - the design and engineering of electronic transfer cofactors, proteins and protein networks, edited by Ronald L. Koder and J.L. Ross Anderson. PMID:26427552

  12. Hair cell regeneration in the bullfrog vestibular otolith organs following aminoglycoside toxicity

    Baird, Richard A.; Torres, M. A.; Schuff, N. R.

    1994-01-01

    Adult bullfrogs were given single intraotic injections of the aminoglycoside antibiotic gentamicin sulfate and sacrificed at postinjection times ranging from 0.5 to 9 days. The saccular and utricular maculae of normal and injected animals were examined in wholemount and cross-section. Intraotic 200 (mu) M gentamicin concentrations resulted in the uniform destruction of the hair bundles and, at later times, the cell bodies of saccular hair cells. In the utriculus, striolar hair cells were selectively damaged while extrastriolar hair cells were relatively unaffected. Regenerating hair cells, identified in sectioned material by their small cell bodies and short, well-formed hair bundles, were seen in the saccular and utricular maculae as early as 24-48 h postinjection. Immature versions of mature hair cell types in both otolith organs were recognized by the presence of absence of a bulbed kinocilia and the relative lengths of their kinocilia and longest sterocilia. Utricular hair cell types with kinocilia longer than their longest stereocilia were observed at earlier times than hair cell types with shorter kinocilia. In the same sacculus, the hair bundles of gentamicin-treated animals, even at 9 days postinjection, were significantly smaller than those of normal animals. The hair bundles of utricular hair cells, on the other hand, reached full maturity within the same time period.

  13. Multielemental hair composition of Brazilian Indian populational groups by instrumental neutron activation analysis

    Multielemental composition of hair samples of Indian populations living in the Xingu Park Reservation, in the Brazilian Amazonic region has been determined for the first time, by INAA. Irradiations were carried out at the Interfaculty Reactor Institute (Delft, The Netherlands) and, using a combination of different irradiation and decay times, about 40 elements could be determined in the hair. Previous analysis made at the Radiochemistry Division of IPEN/CNEN-SP (Brazilian Nuclear Energy Commission) of hair samples of a Brazilian control population allowed the determination of 20 elements, also by INAA. Comparison of the data obtained for the Indian populations and the controls showed very significant differences in elemental compositions for some elements, like Hg, Mn and Al while for others, like Cu and Zn, the concentrations were similar. A discussion of the differences found for other elements also is made. (author)

  14. Equivariant bundle gerbes

    Murray, Michael K; Stevenson, Danny; Vozzo, Raymond F

    2015-01-01

    We develop the theory of simplicial extensions for bundle gerbes and their characteristic classes. This formalism is used to study descent problems and equivariance for bundle gerbes. We consider in detail two examples: the basic bundle gerbe on a unitary group and a string structure for a principal bundle. We show that the basic bundle gerbe is equivariant for the conjugation action and calculate its characteristic class and that a string structure gives rise to a bundle gerbe which is equivariant for a natural action of the String 2-group.

  15. Strategic Aspects of Bundling

    The increase of bundle supply has become widespread in several sectors (for instance in telecommunications and energy fields). This paper review relates strategic aspects of bundling. The main purpose of this paper is to analyze profitability of bundling strategies according to the degree of competition and the characteristics of goods. Moreover, bundling can be used as price discrimination tool, screening device or entry barriers. In monopoly case bundling strategy is efficient to sort consumers in different categories in order to capture a maximum of surplus. However, when competition increases, the profitability on bundling strategies depends on correlation of consumers' reservations values. (author)

  16. Analyses of regenerative wave patterns in adult hair follicle populations reveal macro-environmental regulation of stem cell activity

    Plikus, Maksim V; Widelitz, Randall B; Maxson, Rob; Chuong, Cheng-ming

    2009-01-01

    The control of hair growth in the adult mammalian coat is a fascinating topic which has just begun to be explored with molecular genetic tools. Complex hair cycle domains and regenerative hair waves are present in normal adult (> 2 month) mice, but more apparent in mutants with cyclic alopecia phenotypes. Each hair cycle domain consists of initiation site(s), a propagating wave and boundaries. By analyzing the dynamics of hair growth, time required for regeneration after plucking, in situ hyb...

  17. Activation analysis of hair as an indicator of contamination of man by environmental trace element pollutants

    The burning of fossil fuel, discharges from metallurgical and chemical plants, the wide use of chemicals, and other human activities, result in releasing into the biosphere large quantities of elements which are found in relatively low concentrations in the human organism. The pollution of the biosphere by such trace elements, and in particular heavy metals, has reached such proportions that on the scale of significance of the factors causing the 'stressed' state of the environment of heavy metals occupy the second place and, according to forecasts, may in the future move on to the first. In the problem of pollution of the biosphere, man himself undoubtedly occupies the central position as a target. The pollution of air, soil and water, the contamination of micro-organisms, plants and animals are certainly growing into a serious threat and leading to heavy losses. However, it would be a real disaster if man himself became contaminated to levels giving rise to large scale harmful somatic or genetic effects. It is therefore an urgent problem today to determine the initial levels of trace elements in man and the extent of his contamination in areas where these elements are expected to show anomalous concentrations. Attention should be paid in the first place to those trace elements which probably play no physiological role, are particularly abundant in the environment, and have high toxicity (arsenic, mercury, lead, cadmium, etc.). Moreover, it should be born in mind that in anomalously high concentrations even the physiologically necessary trace elements (copper, zinc, manganese, fluorine, etc.) cause harmful effects. This paper justifies the use of hair samples as a biological indicator of environmental pollutants from physiological and morphological aspect and recommends on sample preparation and analysis methods

  18. Wnt activation protects against neomycin-induced hair cell damage in the mouse cochlea.

    Liu, L; Chen, Y; Qi, J; Zhang, Y; He, Y; Ni, W; Li, W; Zhang, S; Sun, S; Taketo, M M; Wang, L; Chai, R; Li, H

    2016-01-01

    Recent studies have reported the role of Wnt/β-catenin signaling in hair cell (HC) development, regeneration, and differentiation in the mouse cochlea; however, the role of Wnt/β-catenin signaling in HC protection remains unknown. In this study, we took advantage of transgenic mice to specifically knockout or overactivate the canonical Wnt signaling mediator β-catenin in HCs, which allowed us to investigate the role of Wnt/β-catenin signaling in protecting HCs against neomycin-induced damage. We first showed that loss of β-catenin in HCs made them more vulnerable to neomycin-induced injury, while constitutive activation of β-catenin in HCs reduced HC loss both in vivo and in vitro. We then showed that loss of β-catenin in HCs increased caspase-mediated apoptosis induced by neomycin injury, while β-catenin overexpression inhibited caspase-mediated apoptosis. Finally, we demonstrated that loss of β-catenin in HCs led to increased expression of forkhead box O3 transcription factor (Foxo3) and Bim along with decreased expression of antioxidant enzymes; thus, there were increased levels of reactive oxygen species (ROS) after neomycin treatment that might be responsible for the increased aminoglycoside sensitivity of HCs. In contrast, β-catenin overexpression reduced Foxo3 and Bim expression and ROS levels, suggesting that β-catenin is protective against neomycin-induced HC loss. Our findings demonstrate that Wnt/β-catenin signaling has an important role in protecting HCs against neomycin-induced HC loss and thus might be a new therapeutic target for the prevention of HC death. PMID:26962686

  19. Hair Loss

    ... 2 • 3 • 4 For Teens For Kids For Parents MORE ON THIS TOPIC Trichotillomania Dealing With a Health Condition Taking Care of Your Hair Skin, Hair, and Nails Body Image and Self-Esteem Alopecia: Kayla's Story Dealing With Cancer Contact Us ...

  20. Determination of As by instrumental neutron activation analysis in sectioned hair samples for forensic purposes: chronic or acute poisoning?

    Autopsy of 29-year old woman suspicious of committing suicide by the ingestion of As2O3 yielded contradictory findings. All pathological findings as well as clinical symptoms suggested acute poisoning, while a highly elevated As level of 26.4 μg g-1 in her hair collected at the autopsy, which was determined with inductively coupled plasma mass spectrometry indicated chronic poisoning. To elucidate this discrepancy, instrumental neutron activation analysis (INAA) with proven accuracy was performed of another set of sectioned hair samples. Levels of As found by INAA in the range of 0.16-0.26 μg g-1 excluded chronic poisoning, because the person died after approximately 14 h after the As2O3 ingestion. Two reasons for the discordant As results obtained by ICP-MS and INAA are considered: (1) accidental, non-removed contamination of hair on the As2O3 ingestion; (2) erroneous performance of ICP-MS. (author)

  1. Application of neutron activation analysis for mercury species determination in scalp hair samples from Malaysia, Libya and Jordan

    Neutron activation analysis was used to determine the levels of total mercury and methylmercury in hair samples obtained from 400 Malaysian (Kuala Lumpur), Libyan (Benghazi) and Jordanian (Amman) donors. Results show that the level of total mercury in hair samples of the Malaysian group (3.38 mg x kg-1) was significantly higher than those of Libyan (0.81 mg x kg-1) and Jordanian groups (0.69 mg x kg-1). Likewise, a significant difference was found between the level of methylmercury of the Malaysian group (1.13 mg x kg-1) and those of the Libyan (0.04 mg x kg-1) and Jordanian groups (0.13 mg x kg-1). This difference could be attributed to the variation in life habits especially fish diet and to the local environment of each population. On the other hand, no significant differences were found between the level of total mercury and methylmercury in hair samples of the Libyan and Jordanian residents. (author)

  2. Determination of uranium in human head hair of a Brazilian populational group by epithermal neutron activation analysis

    Hair analysis is extensively used in forensic sciences, assessment of occupational or environmental exposure and in some cases also for clinical and nutritional studies. Hair has a series of advantages in relation to other biomonitors, like blood and urine, since it is very easy to collect, very stable at room temperature and it represents not only instantaneous concentrations, but it can reveal the exposure along a given period of time. The assessment of environmental or occupational exposure to uranium is generally done by means of urine analysis, although a few papers have described attempts to use hair as a biomonitor. In the present work, epithermal neutron activation analysis has been used to establish base-line concentrations for a Brazilian populational group, living in Sao Paulo and not exposed to uranium, either environmentally or occupationally. For quality control, the reference materials Pine Needles NIST 1575 and Basalt USGS BCR-1 were used. The concentrations obtained for the control population studied up to now varied from about 2 to 50 ng x g-1. (author)

  3. Neutron activation analysis of hair elements. Influence of residence, occupation and health status

    26 trace elements are determined in human head hair by n.a.a. in combination with a.a.s. and a.e.s. Mean values obtained are compared with literature data. For selected elements the influence of age in the first years of life, of residence, professional burden, hormones, and diseases was studied. (author)

  4. Immunocosmeceuticals: An emerging trend in repairing human hair damage

    Karthika Selvan

    2013-01-01

    Full Text Available Hair is one of the most important portions for beauty care and in recent years grooming and cosmetic treatment of hair has drastically risen. Substantially, it may deteriorate and weaken the hair by modification of keratin protein. This makes the hair dry, brittle and split vend occurs due to loss of hair strength and the damage further increases with cosmetic treatments. The various poor ingredients are being used for repairing which have extremely poor compatibility with hair. Now the hair care products can be introduced with an active ingredient comprising a yolk derived anti-hair antibody immunoglobin obtained from egg of chickens immunized with damaged hair as antigen. This immuno-cosmeceuticals can repair the hair damage and imparts flexibility and smoothness to the hair. These effects are not lost by the ordinary shampooing. This article focuses on the characteristic of human hair, its damaging processes and the effects of immuno-cosmeceuticals for repairing the hair damage.

  5. Improved biolistic transfection of hair cells.

    Hongyu Zhao

    Full Text Available Transient transfection of hair cells has proven challenging. Here we describe modifications to the Bio-Rad Helios Gene Gun that, along with an optimized protocol, improve transfection of bullfrog, chick, and mouse hair cells. The increased penetrating power afforded by our method allowed us to transfect mouse hair cells from the basal side, through the basilar membrane; this configuration protects hair bundles from damage during the procedure. We characterized the efficiency of transfection of mouse hair cells with fluorescently-tagged actin fusion protein using both the optimized procedure and a published procedure; while the efficiency of the two methods was similar, the morphology of transfected hair cells was improved with the new procedure. In addition, using the improved method, we were able to transfect hair cells in the bullfrog sacculus and chick cochlea for the first time. We used fluorescent-protein fusions of harmonin b (USH1C and PMCA2 (ATP2B2; plasma-membrane Ca(2+-ATPase isoform 2 to examine protein distribution in hair cells. While PMCA2-EGFP localization was similar to endogenous PMCA2 detected with antibodies, high levels of harmonin-EGFP were found at stereocilia tapers in bullfrog and chick, but not mouse; by contrast, harmonin-EGFP was concentrated in stereocilia tips in mouse hair cells.

  6. Comparative transduction mechanisms of hair cells in the bullfrog utriculus. 1: Responses to intracellular current

    Baird, Richard A.

    1994-01-01

    Hair cells in the bullfrog sacculus are specifically adapted to sense small-amplitude, high-frequency linear accelerations. These hair cells display many properties that are undesirable or inappropriate for hair cells that must provide static gravity sensitivity. This study resulted in part due to an interest in seeing how the transduction mechanisms of hair cells in a gravity-sensing otolith endorgan would differ from those in the bullfrog sacculus. The bullfrog utriculus is an appropriate model for these studies, because its structure is representative of higher vertebrates in general and its function as a sensor of static gravity and dynamic linear acceleration is well known. Hair cells in the bullfrog utriculus, classifiable as Type 2 by cell body and synapse morphology, differ markedly in hair bundle morphology from those in the bullfrog sacculus. Moreover, the hair bundle morphologies of utricular hair cells, unlike those in the sacculus, differ in different membrane regions.

  7. Einstein Hair

    Kolyvaris, Theodoros; Papantonopoulos, Eleftherios; Siopsis, George

    2011-01-01

    We consider a gravitating system of vanishing cosmological constant consisting of an electromagnetic field and a scalar field coupled to the Einstein tensor. A Reissner-Nordstr{\\o}m black hole undergoes a second-order phase transition to a hairy black hole of generally anisotropic hair at a certain critical temperature which we compute. The no-hair theorem is evaded due to the coupling between the scalar field and the Einstein tensor ("Einstein hair"). We calculate explicitly the properties of a hairy black hole configuration near the critical temperature and show that it is energetically favorable over the corresponding Reissner-Nordstr{\\o}m black hole.

  8. Automatic Hair Segmentation in the Wild

    Julian, Pauline; Dehais, Christophe; Lauze, Francois Bernard;

    2010-01-01

    This paper presents an algorithm for segmenting the hair region in uncontrolled, real life conditions images. Our method is based on a simple statistical hair shape model representing the upper hair part. We detect this region by minimizing an energy which uses active shape and active contour. Th...

  9. Hair cell recovery in mitotically blocked cultures of the bullfrog saccule

    Baird, R. A.; Burton, M. D.; Fashena, D. S.; Naeger, R. A.

    2000-01-01

    Hair cells in many nonmammalian vertebrates are regenerated by the mitotic division of supporting cell progenitors and the differentiation of the resulting progeny into new hair cells and supporting cells. Recent studies have shown that nonmitotic hair cell recovery after aminoglycoside-induced damage can also occur in the vestibular organs. Using hair cell and supporting cell immunocytochemical markers, we have used confocal and electron microscopy to examine the fate of damaged hair cells and the origin of immature hair cells after gentamicin treatment in mitotically blocked cultures of the bullfrog saccule. Extruding and fragmenting hair cells, which undergo apoptotic cell death, are replaced by scar formations. After losing their bundles, sublethally damaged hair cells remain in the sensory epithelium for prolonged periods, acquiring supporting cell-like morphology and immunoreactivity. These modes of damage appear to be mutually exclusive, implying that sublethally damaged hair cells repair their bundles. Transitional cells, coexpressing hair cell and supporting cell markers, are seen near scar formations created by the expansion of neighboring supporting cells. Most of these cells have morphology and immunoreactivity similar to that of sublethally damaged hair cells. Ultrastructural analysis also reveals that most immature hair cells had autophagic vacuoles, implying that they originated from damaged hair cells rather than supporting cells. Some transitional cells are supporting cells participating in scar formations. Supporting cells also decrease in number during hair cell recovery, supporting the conclusion that some supporting cells undergo phenotypic conversion into hair cells without an intervening mitotic event.

  10. Hair Loss

    ... resources Meet our partners Español Donate Diseases and treatments Acne and rosacea Bumps and growths Color problems Contagious skin diseases Cosmetic treatments Dry / sweaty skin Eczema / dermatitis Hair and scalp ...

  11. Your Hair

    ... warm and provides a little cushioning for your skull. Eyelashes protect your eyes by decreasing the amount ... Colors What kind of hair do you have — black and curly, blond and straight, or some other ...

  12. Mesenchymal-epithelial interactions during hair follicle morphogenesis and cycling

    Sennett, Rachel; Rendl, Michael

    2012-01-01

    Embryonic hair follicle induction and formation are regulated by mesenchymal-epithelial interactions between specialized dermal cells and epidermal stem cells that switch to a hair fate. Similarly, during postnatal hair growth, communication between mesenchymal dermal papilla cells and surrounding epithelial matrix cells coordinates hair shaft production. Adult hair follicle regeneration in the hair cycle again is thought to be controlled by activating signals originating from the mesenchymal...

  13. Activation of the pseudokinase MLKL unleashes the four-helix bundle domain to induce membrane localization and necroptotic cell death

    Hildebrand, Joanne M.; Tanzer, Maria C; Lucet, Isabelle S; Young, Samuel N.; Spall, Sukhdeep K; Sharma, Pooja; Pierotti, Catia; Garnier, Jean-Marc; Dobson, Renwick C. J.; Andrew I Webb; Tripaydonis, Anne; Babon, Jeffrey J.; Mulcair, Mark D.; Scanlon, Martin J.; Alexander, Warren S

    2014-01-01

    The four-helix bundle (4HB) domain of Mixed Lineage Kinase Domain-Like (MLKL) bears two clusters of residues that are required for cell death by necroptosis. Mutations within a cluster centered on the α4 helix of the 4HB domain of MLKL prevented its membrane translocation, oligomerization, and ability to induce necroptosis. This cluster is composed principally of acidic residues and therefore challenges the idea that the 4HB domain engages negatively charged phospholipid membranes via a conve...

  14. VEGF induces proliferation of human hair follicle dermal papilla cells through VEGFR-2-mediated activation of ERK

    Vascular endothelial growth factor (VEGF) is one of the strongest regulators of physiological and pathological angiogenesis. VEGF receptor 2 (VEGFR-2), the primary receptor for VEGF, is thought to mediate major functional effects of VEGF. Previously, we have localized both VEGF and VEGFR-2 in human hair follicles. In this study, we further defined the expression and roles of VEGFR-2 on human hair follicle dermal papilla (DP) cells. The expression of VEGFR-2 on DP cells was examined by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analysis separately, and localization of VEGFR-2 was defined by immunofluorescence. The effect of VEGF on DP cells was analyzed by MTT assays and specific inhibitors. Finally, the role of VEGF involved in the signaling pathways was investigated by Western blot. RT-PCR and Western blot analysis demonstrated the expression of VEGFR-2 on DP cells. Immunostaining for VEGFR-2 showed strong signal on cultured human DP cells in vitro. Exogenous VEGF165 stimulated proliferation of DP cells in a dose-dependent manner. Furthermore, this stimulation was blocked by a VEGFR-2 neutralizing antibody (MAB3571) and an ERK inhibitor (PD98059). VEGF165-induced phosphorylation of ERK1/2 was abolished by MAB3571 and PD98059, while the phosphorylation of p38, JNK and AKT were not changed by VEGF165. Taken together, VEGFR-2 is expressed on primary human hair follicle DP cells and VEGF induces proliferation of DP cells through VEGFR-2/ERK pathway, but not p38, JNK or AKT signaling. -- Highlights: ► We examine the expression of VEGFR-2 on cultured human dermal papilla (DP) cells. ► VEGF165 stimulated proliferation of human DP cells in a dose-dependent manner. ► This stimulation was through VEGFR-2-mediated activation of ERK.

  15. Plant Growth Promotion Activity of Keratinolytic Fungi Growing on a Recalcitrant Waste Known as “Hair Waste”

    Cavello, Ivana A.; Crespo, Juan M.; García, Sabrina S.; Zapiola, José M.; Luna, María F.; Cavalitto, Sebastián F.

    2015-01-01

    Purpureocillium lilacinum (Thom) Samsom is one of the most studied fungi in the control of plant parasitic nematodes. However, there is not specific information on its ability to inhibit some pathogenic bacteria, fungi, or yeast. This work reports the production of several antifungal hydrolytic enzymes by a strain of P. lilacinum when it is grown in a medium containing hair waste. The growth of several plant-pathogenic fungi, Alternaria alternata, Aspergillus niger, and Fusarium culmorum, was considerably affected by the presence of P. lilacinum's supernatant. Besides antifungal activity, P. lilacinum demonstrates the capability to produce indoleacetic acid and ammonia during time cultivation on hair waste medium. Plant growth-promoting activity by cell-free supernatant was evidenced through the increase of the percentage of tomato seed germination from 71 to 85% after 48 hours. A 21-day plant growth assay using tomato plants indicates that crude supernatant promotes the growth of the plants similar to a reference fertilizer (p > 0.05). These results suggest that both strain and the supernatant may have potential to be considered as a potent biocontrol agent with multiple plant growth-promoting properties. To our knowledge, this is the first report on the antifungal, IAA production and tomato growth enhancing compounds produced by P. lilacinum LPSC #876. PMID:26697226

  16. Plant Growth Promotion Activity of Keratinolytic Fungi Growing on a Recalcitrant Waste Known as “Hair Waste”

    Ivana A. Cavello

    2015-01-01

    Full Text Available Purpureocillium lilacinum (Thom Samsom is one of the most studied fungi in the control of plant parasitic nematodes. However, there is not specific information on its ability to inhibit some pathogenic bacteria, fungi, or yeast. This work reports the production of several antifungal hydrolytic enzymes by a strain of P. lilacinum when it is grown in a medium containing hair waste. The growth of several plant-pathogenic fungi, Alternaria alternata, Aspergillus niger, and Fusarium culmorum, was considerably affected by the presence of P. lilacinum’s supernatant. Besides antifungal activity, P. lilacinum demonstrates the capability to produce indoleacetic acid and ammonia during time cultivation on hair waste medium. Plant growth-promoting activity by cell-free supernatant was evidenced through the increase of the percentage of tomato seed germination from 71 to 85% after 48 hours. A 21-day plant growth assay using tomato plants indicates that crude supernatant promotes the growth of the plants similar to a reference fertilizer (p>0.05. These results suggest that both strain and the supernatant may have potential to be considered as a potent biocontrol agent with multiple plant growth-promoting properties. To our knowledge, this is the first report on the antifungal, IAA production and tomato growth enhancing compounds produced by P. lilacinum LPSC #876.

  17. The amazing miniorgan: Hair follicle

    Çiler Çelik Özenci

    2014-06-01

    Full Text Available Hair is a primary characteristic of mammals, and exerts a wide range of functions including thermoregulation, physical protection, sensory activity, and social interactions. The hair shaft consists of terminally differentiated keratinocytes that are produced by the hair follicle. Hair follicle development takes place during fetal skin development and relies on tightly regulated ectodermal–mesodermal interactions. Hair follicles form during embryonic development and, after birth, undergo recurrent cycling of growth (anagen, apoptosis-driven regression (catagen, and relative quiescence (telogen. As a functional mini-organ, the hair follicle develops in an environment with dynamic and alternating changes of diverse molecular signals. Our molecular understanding of hair follicle biology relies heavily on genetically engineered mouse models with abnormalities in hair structure, growth, and/or pigmentation and significant advances have been made toward the identification of key signaling pathways and the regulatory genes involved. In this review, the basic concepts of hair follicle, a mini-complex organ, biology will be presented and its importance in clinical applications will be summarized.

  18. Removing Hair Safely

    ... For Consumers Home For Consumers Consumer Updates Removing Hair Safely Share Tweet Linkedin Pin it More sharing ... methods of hair removal. back to top Laser Hair Removal In this method, a laser destroys hair ...

  19. Both pre- and postsynaptic activity of Nsf prevents degeneration of hair-cell synapses.

    Weike Mo

    Full Text Available Vesicle fusion contributes to the maintenance of synapses in the nervous system by mediating synaptic transmission, release of neurotrophic factors, and trafficking of membrane receptors. N-ethylmaleimide-sensitive factor (NSF is indispensible for dissociation of the SNARE-complex following vesicle fusion. Although NSF function has been characterized extensively in vitro, the in vivo role of NSF in vertebrate synaptogenesis is relatively unexplored. Zebrafish possess two nsf genes, nsf and nsfb. Here, we examine the function of either Nsf or Nsfb in the pre- and postsynaptic cells of the zebrafish lateral line organ and demonstrate that Nsf, but not Nsfb, is required for maintenance of afferent synapses in hair cells. In addition to peripheral defects in nsf mutants, neurodegeneration of glutamatergic synapses in the central nervous system also occurs in the absence of Nsf function. Expression of an nsf transgene in a null background indicates that stabilization of synapses requires Nsf function in both hair cells and afferent neurons. To identify potential targets of Nsf-mediated fusion, we examined the expression of genes implicated in stabilizing synapses and found that transcripts for multiple genes including brain-derived neurotrophic factor (bdnf were significantly reduced in nsf mutants. With regard to trafficking of BDNF, we observed a striking accumulation of BDNF in the neurites of nsf mutant afferent neurons. In addition, injection of recombinant BDNF protein partially rescued the degeneration of afferent synapses in nsf mutants. These results establish a role for Nsf in the maintenance of synaptic contacts between hair cells and afferent neurons, mediated in part via the secretion of trophic signaling factors.

  20. 6-Gingerol inhibits hair shaft growth in cultured human hair follicles and modulates hair growth in mice.

    Yong Miao

    Full Text Available Ginger (Zingiber officinale has been traditionally used to check hair loss and stimulate hair growth in East Asia. Several companies produce shampoo containing an extract of ginger claimed to have anti-hair loss and hair growth promotion properties. However, there is no scientific evidence to back up these claims. This study was undertaken to measure 6-gingerol, the main active component of ginger, on hair shaft elongation in vitro and hair growth in vivo, and to investigate its effect on human dermal papilla cells (DPCs in vivo and in vitro. 6-Gingerol suppressed hair growth in hair follicles in culture and the proliferation of cultured DPCs. The growth inhibition of DPCs by 6-gingerol in vitro may reflect a decrease in the Bcl-2/Bax ratio. Similar results were obtained in vivo. The results of this study showed that 6-gingerol does not have the ability to promote hair growth, on the contrary, can suppress human hair growth via its inhibitory and pro-apoptotic effects on DPCs in vitro, and can cause prolongation of telogen phase in vivo. Thus, 6-gingerol rather than being a hair growth stimulating drug, it is a potential hair growth suppressive drug; i.e. for hair removal.

  1. Bundling and Tying

    Nicholas Economides

    2014-01-01

    We discuss strategic ways that sellers can use tying and bundling with requirement conditions to extract consumer surplus. We analyze different types of tying and bundling creating (i) intra-product price discrimination; (ii) intra-consumer price discrimination; and (iii) inter-product price discrimination, and assess the antitrust liability that these practices may entail. We also discuss the impact on consumers and competition, as well as potential antitrust liability of bundling “incontest...

  2. Nanotechnology-Based Cosmetics for Hair Care

    Jamie Rosen; Angelo Landriscina; Friedman, Adam J.

    2015-01-01

    Hair is a significant indicator of health and can have a major impact on an individual’s cosmetic appearance. Research within the cosmetics industry has revealed that when nanomaterials are engineered into hair care, they can enhance the benefits of active ingredients in order to improve hair cosmesis. Within the cosmetics arena, the unique size and intrinsic properties of nanoparticles can be tailored to target the hair follicle and shaft. This review aims to provide an overview of cosmetic ...

  3. Multielement analysis of human hair and kidney stones by instrumental neutron activation analysis with the k0-standardization method

    This paper focuses on the evaluation of the k0 method of instrumental neutron activation analysis in biological materials. The method has been applied in multielement analysis of human hair standard reference materials from IAEA, No. 085, No. 086 and from NIES (National Institute for Environmental Sciences) No. 5. Hair samples from people resident in different parts of Malaysia, in addition to a sample from Japan, were analyzed. In addition, human kidney stones from members of the Malaysian population have been analyzed for minor and trace elements. More than 25 elements have been determined. The samples were irradiated in the rotary rack (Lazy Susan) at the TRIGA Mark II reactor of the Malaysian Institute for Nuclear Technology and Research (MINT). The accuracy of the method was ascertained by analysis of other reference materials, including 1573 tomato leaves and 1572 citrus leaves. In this method the deviation of the 1/E1+α epithermal neutron flux distribution from the 1/E law (P/T ratio) for true coincidence effects of the γ-ray cascade and the HPGe detector efficiency were determined and corrected for

  4. Multielement analysis of human hair and kidney stones by instrumental neutron activation analysis with the k0-standardization method.

    Abugassa, I; Sarmani, S B; Samat, S B

    1999-06-01

    This paper focuses on the evaluation of the k0 method of instrumental neutron activation analysis in biological materials. The method has been applied in multielement analysis of human hair standard reference materials from IAEA, No. 085, No. 086 and from NIES (National Institute for Environmental Sciences) No. 5. Hair samples from people resident in different parts of Malaysia, in addition to a sample from Japan, were analyzed. In addition, human kidney stones from members of the Malaysian population have been analyzed for minor and trace elements. More than 25 elements have been determined. The samples were irradiated in the rotary rack (Lazy Susan) at the TRIGA Mark II reactor of the Malaysian Institute for Nuclear Technology and Research (MINT). The accuracy of the method was ascertained by analysis of other reference materials, including 1573 tomato leaves and 1572 citrus leaves. In this method the deviation of the 1/E1+ alpha epithermal neutron flux distribution from the 1/E law (P/T ratio) for true coincidence effects of the gamma-ray cascade and the HPGe detector efficiency were determined and corrected for. PMID:10355102

  5. Contact fiber bundles

    Lerman, Eugene

    2003-01-01

    We define contact fiber bundles and investigate conditions for the existence of contact structures on the total space of such a bundle. The results are analogous to minimal coupling in symplectic geometry. The two applications are construction of K-contact manifolds generalizing Yamazaki's fiber join construction and a cross-section theorem for contact moment maps

  6. Principal noncommutative torus bundles

    Echterhoff, Siegfried; Nest, Ryszard; Oyono-Oyono, Herve

    2008-01-01

    of bivariant K-theory (denoted RKK-theory) due to Kasparov. Using earlier results of Echterhoff and Williams, we shall give a complete classification of principal non-commutative torus bundles up to equivariant Morita equivalence. We then study these bundles as topological fibrations (forgetting the...

  7. HCN channels are not required for mechanotransduction in sensory hair cells of the mouse inner ear.

    Geoffrey C Horwitz

    Full Text Available The molecular composition of the hair cell transduction channel has not been identified. Here we explore the novel hypothesis that hair cell transduction channels include HCN subunits. The HCN family of ion channels includes four members, HCN1-4. They were originally identified as the molecular correlates of the hyperpolarization-activated, cyclic nucleotide gated ion channels that carry currents known as If, IQ or Ih. However, based on recent evidence it has been suggested that HCN subunits may also be components of the elusive hair cell transduction channel. To investigate this hypothesis we examined expression of mRNA that encodes HCN1-4 in sensory epithelia of the mouse inner ear, immunolocalization of HCN subunits 1, 2 and 4, uptake of the transduction channel permeable dye, FM1-43 and electrophysiological measurement of mechanotransduction current. Dye uptake and transduction current were assayed in cochlear and vestibular hair cells of wildtype mice exposed to HCN channel blockers or a dominant-negative form of HCN2 that contained a pore mutation and in mutant mice that lacked HCN1, HCN2 or both. We found robust expression of HCNs 1, 2 and 4 but little evidence that localized HCN subunits in hair bundles, the site of mechanotransduction. Although high concentrations of the HCN antagonist, ZD7288, blocked 50-70% of the transduction current, we found no reduction of transduction current in either cochlear or vestibular hair cells of HCN1- or HCN2- deficient mice relative to wild-type mice. Furthermore, mice that lacked both HCN1 and HCN2 also had normal transduction currents. Lastly, we found that mice exposed to the dominant-negative mutant form of HCN2 had normal transduction currents as well. Taken together, the evidence suggests that HCN subunits are not required for mechanotransduction in hair cells of the mouse inner ear.

  8. "My hair or my health:" Overcoming barriers to physical activity in African American women with a focus on hairstyle-related factors.

    Huebschmann, Amy G; Campbell, Lucille Johnson; Brown, Candace S; Dunn, Andrea L

    2016-01-01

    Physical activity disparities among African American (AA) women may be related to sociocultural barriers, including difficulties with restyling hair after exercise. We sought to identify physical activity barriers and facilitators in AA women with a focus on sociocultural factors related to hairstyle maintenance. Participants (n = 51) were AA women aged 19-73 years who completed valid surveys and participated in structured focus groups, stratified by age and physical activity levels, from November 2012 to February 2013. The Constant Comparison method was used to develop qualitative themes for barriers and facilitators. The most frequently reported general physical activity barrier among exercisers was "lack of money" (27%) and among non-exercisers was "lack of self-discipline" (57%). A hairstyle-related barrier of "sweating out my hairstyle" was reported by 7% of exercisers and 29% of non-exercisers. This hairstyle-related barrier included the need for extra time and money to restyle hair due to perspiration. Hairstyle-related facilitators included: prioritizing health over hairstyle and high self-efficacy to restyle hair after perspiration. Participants were interested in resources to simplify hairstyle maintenance. AA women whose hairstyle is affected by perspiration may avoid physical activity due to time and financial burdens. Increasing self-efficacy to restyle hair after perspiration may help to overcome this barrier. PMID:26495938

  9. Preliminary Characterization of Voltage-Activated Whole-Cell Currents in Developing Human Vestibular Hair Cells and Calyx Afferent Terminals

    Lim, Rebecca; Drury, Hannah R.; Camp, Aaron J.; Tadros, Melissa A; Robert J Callister; Brichta, Alan M.

    2014-01-01

    We present preliminary functional data from human vestibular hair cells and primary afferent calyx terminals during fetal development. Whole-cell recordings were obtained from hair cells or calyx terminals in semi-intact cristae prepared from human fetuses aged between 11 and 18 weeks gestation (WG). During early fetal development (11–14 WG), hair cells expressed whole-cell conductances that were qualitatively similar but quantitatively smaller than those observed previously in mature rodent ...

  10. Body Hair

    ... and uncomfortable. If you decide to use a hair-removal cream, make sure it says it’s gentle enough for the pubic area. Don’t put on any product that could sting, like aftershave lotion. To help avoid irritation, don’t use products with added dyes or fragrances. If you have more questions about ...

  11. Calbindin and parvalbumin are early markers of non-mitotically regenerating hair cells in the bullfrog vestibular otolith organs

    Steyger, P. S.; Burton, M.; Hawkins, J. R.; Schuff, N. R.; Baird, R. A.

    1997-01-01

    Earlier studies have demonstrated hair cell regeneration in the absence of cell proliferation, and suggested that supporting cells could phenotypically convert into hair cells following hair cell loss. Because calcium-binding proteins are involved in gene up-regulation, cell growth, and cell differentiation, we wished to determine if these proteins were up-regulated in scar formations and regenerating hair cells following gentamicin treatment. Calbindin and parvalbumin immunolabeling was examined in control or gentamicin-treated (GT) bullfrog saccular and utricular explants cultured for 3 days in amphibian culture medium or amphibian culture medium supplemented with aphidicolin, a blocker of nuclear DNA replication in eukaryotic cells. In control cultures, calbindin and parvalbumin immunolabeled the hair bundles and, less intensely, the cell bodies of mature hair cells. In GT or mitotically-blocked GT (MBGT) cultures, calbindin and parvalbumin immunolabeling was also seen in the hair bundles, cuticular plates, and cell bodies of hair cells with immature hair bundles. Thus, these antigens were useful markers for both normal and regenerating hair cells. Supporting cell immunolabeling was not seen in control cultures nor in the majority of supporting cells in GT cultures. In MBGT cultures, calbindin and parvalbumin immunolabeling was up-regulated in the cytosol of single supporting cells participating in scar formations and in supporting cells with hair cell-like characteristics. These data provide further evidence that non-mitotic hair cell regeneration in cultures can be accomplished by the conversion of supporting cells into hair cells.

  12. Research Advances: Pacific Northwest National Laboratory Finds New Way to Detect Destructive Enzyme Activity--Hair Dye Relies on Nanotechnology--Ways to Increase Shelf Life of Milk

    King, Angela G.

    2007-01-01

    Recent advances in various research fields are described. Scientists at the Pacific Northwest National Laboratory have found a new way to detect destructive enzyme activity, scientists in France have found that an ancient hair dye used by ancient people in Greece and Rome relied on nanotechnology and in the U.S. scientists are developing new…

  13. Nanotechnology-Based Cosmetics for Hair Care

    Jamie Rosen

    2015-07-01

    Full Text Available Hair is a significant indicator of health and can have a major impact on an individual’s cosmetic appearance. Research within the cosmetics industry has revealed that when nanomaterials are engineered into hair care, they can enhance the benefits of active ingredients in order to improve hair cosmesis. Within the cosmetics arena, the unique size and intrinsic properties of nanoparticles can be tailored to target the hair follicle and shaft. This review aims to provide an overview of cosmetic nanocarriers that can be employed to improve the appearance of hair.

  14. Kif3a regulates planar polarization of auditory hair cells through both ciliary and non-ciliary mechanisms

    Sipe, Conor W.; Lu, Xiaowei

    2011-01-01

    Auditory hair cells represent one of the most prominent examples of epithelial planar polarity. In the auditory sensory epithelium, planar polarity of individual hair cells is defined by their V-shaped hair bundle, the mechanotransduction organelle located on the apical surface. At the tissue level, all hair cells display uniform planar polarity across the epithelium. Although it is known that tissue planar polarity is controlled by non-canonical Wnt/planar cell polarity (PCP) signaling, the ...

  15. Frequency locking in hair cells: Distinguishing between distinct resonant mechanisms

    Edri, Yuval; Yochelis, Arik

    2016-01-01

    The auditory system displays remarkable mechanical sensitivity and frequency discrimination. These attributes have been shown to rely on an amplification process, which requires biochemical feedback loops. In some systems, the active process was shown to lead to spontaneous oscillations of hair cell bundles. In the last decade, models that display proximity to an oscillatory onset (a.k.a. Hopf bifurcation) have gained increasing support due to many advantages in explaining the hearing phenomenology. Particularly, they exhibit resonant responses to distinct frequencies of incoming sound waves. Unlike previous studies, two types of driving forces are being examined: additive, in which the external forcing term does not couple directly on the systems observable (passive coupling), and parametric, in which the forcing term directly affects the observable and thus intrinsically modifies the systems properties (active coupling). By applying universal principles near the Hopf bifurcation onset, we find several funda...

  16. Tunable N-doped or dual N, S-doped activated hydrothermal carbons derived from human hair and glucose for supercapacitor applications

    Graphical abstract: Tunable mono N- or dual N, S-doped microporous carbons with excellent capacitive performance are prepared from renewable human hair and glucose. -- Highlights: • Green hydrothermal carbonization procedure is used in this work. • Renewable human hair is firstly used to prepared heteroatom-doped carbon materials. • Tunable N-doping or dual N, S-doping could be achieved by controlling the dosage of hair additive. • The multi N, O, S-doped species exhibits synergistic enhancement effect on the whole capacitive performance. • The AHC-4 carbon showed a high capacitance of up to 264 F g−1 in 6 M KOH electrolyte. -- Abstract: In this work, human hair was firstly used to prepared heteroatom-doped carbon materials. Tunable N-doped or dual N, S-doped microporous carbons were successful prepared using glucose and human hair as carbon precursors via a method of hydrothermal carbonization procedure and sequent KOH activation. The electrochemical capacitive performance of the prepared carbons was investigated in KOH electrolyte. The morphology, structure and surface properties of the carbon materials are investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), N2 adsorption, X-ray photoelectron spectroscopy (XPS), Energy Dispersive Spectroscopy (EDS) and Fourier transform infrared spectroscopy (FT-IR). The N- or S-doping could be tuned by controlling the dosage of human hair additives. Due to the synergistic effect of multi N, O, S-doped species, the prepared carbons showed large pseudo-capacitance. The capacitance of AHC-4 could reach 264 F g−1 in KOH electrolyte. AHC-1 shows an acceptable cycle life with relatively high capacitance value of 154 F g−1 after 1000 cycles. The present preparation method is attractive and inspiring for preparation of tunable dual heteroatom-doped carbon materials with high surface area and capacitive performance using renewable biomass

  17. Hair care and dyeing.

    Draelos, Zoe Diana

    2015-01-01

    Alopecia can be effectively camouflaged or worsened through the use of hair care techniques and dyeing. Proper hair care, involving hair styling and the use of mild shampoos and body-building conditioners, can amplify thinning scalp hair; however, chemical processing, including hair dyeing, permanent waving, and hair straightening, can encourage further hair loss through breakage. Many patients suffering from alopecia attempt to improve their hair through extensive manipulation, which only increases problems. Frequent haircuts to minimize split ends, accompanied by gentle handling of the fragile fibers, is best. This chapter offers the dermatologist insight into hair care recommendations for the alopecia patient. PMID:26370650

  18. Skin, Hair, and Nails

    ... distribution of melanin in the cortex of each hair (the same melanin that's found in the epidermis). Hair also contains ... red pigment; people who have blonde or red hair have only a small amount of melanin in their hair. Hair becomes gray when people ...

  19. Preliminary report: NIF laser bundle review

    As requested in the guidance memo 1, this committe determined whether there are compelling reasons to recommend a change from the NIF CDR baseline laser. The baseline bundle design based on a tradeoff between cost and technical risk, which is replicated four times to create the required 192 beams. The baseline amplifier design uses bottom loading 1x4 slab and flashlamp cassettes for amplifier maintenance and large vacuum enclosures (2.5m high x 7m wide in cross-section for each of the two spatial filters in each of the four bundles. The laser beams are arranged in two laser bays configured in a u-shape around the target area. The entire bundle review effort was performed in a very short time (six weeks) and with limited resources (15 personnel part-time). This should be compared to the effort that produced the CDR design (12 months, 50 to 100 personnel). This committee considered three alternate bundle configurations (2x2, 4x2, and 4x4 bundles), and evaluated each bundle against the baseline design using the seven requested issues in the guidance memo: Cost; schedule; performance risk; maintainability/operability; hardware failure cost exposure; activation; and design flexibility. The issues were reviewed to identify differences between each alternate bundle configuration and the baseline

  20. Hair cells use active zones with different voltage dependence of Ca2+ influx to decompose sounds into complementary neural codes.

    Ohn, Tzu-Lun; Rutherford, Mark A; Jing, Zhizi; Jung, Sangyong; Duque-Afonso, Carlos J; Hoch, Gerhard; Picher, Maria Magdalena; Scharinger, Anja; Strenzke, Nicola; Moser, Tobias

    2016-08-01

    For sounds of a given frequency, spiral ganglion neurons (SGNs) with different thresholds and dynamic ranges collectively encode the wide range of audible sound pressures. Heterogeneity of synapses between inner hair cells (IHCs) and SGNs is an attractive candidate mechanism for generating complementary neural codes covering the entire dynamic range. Here, we quantified active zone (AZ) properties as a function of AZ position within mouse IHCs by combining patch clamp and imaging of presynaptic Ca(2+) influx and by immunohistochemistry. We report substantial AZ heterogeneity whereby the voltage of half-maximal activation of Ca(2+) influx ranged over ∼20 mV. Ca(2+) influx at AZs facing away from the ganglion activated at weaker depolarizations. Estimates of AZ size and Ca(2+) channel number were correlated and larger when AZs faced the ganglion. Disruption of the deafness gene GIPC3 in mice shifted the activation of presynaptic Ca(2+) influx to more hyperpolarized potentials and increased the spontaneous SGN discharge. Moreover, Gipc3 disruption enhanced Ca(2+) influx and exocytosis in IHCs, reversed the spatial gradient of maximal Ca(2+) influx in IHCs, and increased the maximal firing rate of SGNs at sound onset. We propose that IHCs diversify Ca(2+) channel properties among AZs and thereby contribute to decomposing auditory information into complementary representations in SGNs. PMID:27462107

  1. candu fuel bundle fabrication

    This paper describes works on CANDU fuel bundle fabrication in the Fuel Fabrication Development and Testing Section (FFDT) of AECL's Chalk River Laboratories. This work does not cover fuel design, pellet manufacturing, Zircaloy material manufacturing, but cover the joining of appendages to sheath tube, endcap preparation and welding, UO2 loading, end plate preparation and welding, and all inspections required in these steps. Materials used in the fabrication of CANDU fuel bundle are: 1)Ceramic UO2 Pellet 2)Zircaloy -4. Fuel Bundle Structural Material 3) Others (Zinc stearate, Colloidal graphite, Beryllium and Heium). Th fabrication of fuel element consist of three process: 1)pellet loading into the sheats, 2) endcap welding, and 3) the element profiling. Endcap welds is tested by metallography and He leak test. The endcaps of the elements are welded to the end plates to form the 37- element bundle assembly

  2. Restrictions of stable bundles

    Balaji, V

    2011-01-01

    The Mehta-Ramanathan theorem ensures that the restriction of a stable vector bundle to a sufficiently high degree complete intersection curve is again stable. We improve the bounds for the "sufficiently high degree" and propose a possibly optimal conjecture.

  3. Trace analysis in human hair

    The hair has been used as a readily available tissue for the trace analysis. It can supply the medical diagnosis and environmental studied. Hair tissue is, potentially, a remarkable diagnostic tool to complement blood serum and urine analysis. The CDTN/CNEN-BH has a large experience on determining the elements within the various ranges of concentration in several kinds of matrices by using neutron activation and atomic absorption spectrometry. This experience has made possible the development of methods using hair so as to determine the detections limits of Al, Cr, Cu, Hg, K, Mn and Zn. (author)

  4. My oh my(osin): Insights into how auditory hair cells count, measure, and shape

    Pollock, Lana M.; Chou, Shih-Wei; McDermott, Brian M., Jr.

    2016-01-01

    The mechanisms underlying mechanosensory hair bundle formation in auditory sensory cells are largely mysterious. In this issue, Lelli et al. (2016. J. Cell Biol. http://dx.doi.org/10.1083/jcb.201509017) reveal that a pair of molecular motors, myosin IIIa and myosin IIIb, is involved in the hair bundle’s morphology and hearing.

  5. Validation of the instrumental neutron activation analysis method for mercury analysis in hair samples used for biomonitoring of mercury environmental contamination

    Environmental mercury contamination has lately become of widespread concern in Brazil owing to gold extraction activities in the Amazon region and also to industrial activities. It is estimated that tonnes of mercury are thrown in the rivers of the Amazon region annually or are evaporated into the open air owing to the amalgamation procedure employed in gold extraction. In the present work, as pail of an IAEA Co-ordinated Research Programme (CRP), three main population groups were studied: a control group of individuals with no suspicion of contamination by mercury; a group of people living near the Billings Dam, located in one of the most heavily industrialized parts of the country, and several Indian tribes living in Xingu Park, an Indian reservation located in the Amazon region. An important part of the CRP was the validation of the analytical methodology for die analysis of total mercury in the hair samples of the population groups studied. Instrumental neutron activation analysis (INAA) was chosen for the analysis of mercury in these samples. It has the advantage of being non-destructive, which can be quite convenient when dealing with a large number of samples, which is the case in epidemiological studies. The experimental procedure consisted of irradiation of the hair samples in the IEA-R1 nuclear research reactor and measurement of the gamma radioactivity of 197Hg. For the validation of the analytical methodology, the following reference materials (RMs) were analysed: IAEA MA-A-2/TM Fish Flesh Homogenate; SHINR GBW-9101 Chinese Human Hair and the candidate RMs IAEA-085 and IAEA-086 Human Hair. The recently acquired RM BCR CRM-397 was also analysed. The accuracy and precision of the INAA method for the analysis of these RMs is discussed, as well as the applicability of the method to the analysis of mercury in the hair of the population groups studied. (author)

  6. Photodynamic therapy for hair removal

    Mohamed H. M. Ali

    2013-05-01

    Full Text Available Background: Unwanted hair is one of the most common medical problems affecting women of reproductive age inducing a lot of psychological stress and threatening their femininity and self-esteem. Old methods of removing unwanted hair include shaving, waxing, chemical depilation, and electrolysis, all of which have temporary results. However laser-assisted hair removal is the most efficient method of long-term hair removal currently available. It is desirable to develop a reduced cost photodynamic therapy (PDT system whose properties should include high efficiency and low side-effects. Method: Mice skin tissues were used in this study and divided into six groups such as controls, free methylene blue (MB incubation, liposome methylene blue (MB incubation, laser without methylene blue (MB, free methylene blue (MB for 3 and 4 hrs and laser, liposome methylene blue (MB for 3 hrs and laser. Methylene blue (MBwas applied to wax epilated areas. The areas were irradiated with CW He-Ne laser system that emits orange-red light with wavelength 632.8 nm and 10 mW at energy density of 5 J/ cm2 for 10 minutes. The UV-visible absorption spectrum was collected by Cary spectrophotometer. Results: Methylene blue (MB is selectively absorbed by actively growing hair follicles due to its cationic property. Methylene blue (MBuntreated sections showed that hair follicle and sebaceous gland are intact and there is no change due to the laser exposure. Free methylene blue (MB sections incubated for 3 hrs showed that He:Ne laser induced destruction in hair follicles, leaving an intact epidermis. Treated section with free methylene blue (MB for 4 hrs showed degeneration and necrosis in hair follicle, leaving an intact epidermis. Liposomal methylene blue (MB sections incubated for 3 hrs showed He:Ne laser induced destruction in hair follicles with intradermal leucocytic infiltration. Conclusions: Low power CW He:Ne laser and methylene blue (MB offered a successful PDT system

  7. Live imaging the phagocytic activity of inner ear supporting cells in response to hair cell death.

    Monzack, E L; May, L A; Roy, S; Gale, J E; Cunningham, L L

    2015-12-01

    Hearing loss and balance disorders affect millions of people worldwide. Sensory transduction in the inner ear requires both mechanosensory hair cells (HCs) and surrounding glia-like supporting cells (SCs). HCs are susceptible to death from aging, noise overexposure, and treatment with therapeutic drugs that have ototoxic side effects; these ototoxic drugs include the aminoglycoside antibiotics and the antineoplastic drug cisplatin. Although both classes of drugs are known to kill HCs, their effects on SCs are less well understood. Recent data indicate that SCs sense and respond to HC stress, and that their responses can influence HC death, survival, and phagocytosis. These responses to HC stress and death are critical to the health of the inner ear. Here we have used live confocal imaging of the adult mouse utricle, to examine the SC responses to HC death caused by aminoglycosides or cisplatin. Our data indicate that when HCs are killed by aminoglycosides, SCs efficiently remove HC corpses from the sensory epithelium in a process that includes constricting the apical portion of the HC after loss of membrane integrity. SCs then form a phagosome, which can completely engulf the remaining HC body, a phenomenon not previously reported in mammals. In contrast, cisplatin treatment results in accumulation of dead HCs in the sensory epithelium, accompanied by an increase in SC death. The surviving SCs constrict fewer HCs and display impaired phagocytosis. These data are supported by in vivo experiments, in which cochlear SCs show reduced capacity for scar formation in cisplatin-treated mice compared with those treated with aminoglycosides. Together, these data point to a broader defect in the ability of the cisplatin-treated SCs, to preserve tissue health in the mature mammalian inner ear. PMID:25929858

  8. Laser Hair Removal

    ... rashes clinical tools newsletter | contact Share | Hair Removal, Laser A A A AFTER: Two laser hair removal treatments were performed. This picture is ... Procedure Overview With just the right type of laser or Intense Pulsed Light (IPL) technology, suitable hairs ...

  9. Changing Your Hair

    ... Snowboarding, Skating Crushes What's a Booger? Changing Your Hair KidsHealth > For Kids > Changing Your Hair Print A ... straight when it's curly. Treatments That Can Damage Hair Are these treatments OK for kids? That's something ...

  10. Hair spray poisoning

    ... page: //medlineplus.gov/ency/article/002705.htm Hair spray poisoning To use the sharing features on this page, please enable JavaScript. Hair spray poisoning occurs when someone breathes in (inhales) hair ...

  11. Hair dye poisoning

    Hair dye poisoning occurs when someone swallows dye or tint used to color hair. This article is for ... Different types of hair dye contain different harmful ingredients. ... aromatic amino compounds Phenylenediamines Toluene diamines ...

  12. Hair spray poisoning

    Hair spray poisoning occurs when someone breathes in (inhales) hair spray or sprays it down their throat or into their eyes. ... The harmful ingredients in hair spray are: Carboxymethylcellulose ... Polyvinyl alcohol Propylene glycol Polyvinylpyrrolidone

  13. Proteomic Analysis of Hair Follicles

    Ishioka, Noriaki; Terada, Masahiro; Yamada, Shin; Seki, Masaya; Takahashi, Rika; Majima, Hideyuki J.; Higashibata, Akira; Mukai, Chiaki

    2013-02-01

    Hair root cells actively divide in a hair follicle, and they sensitively reflect physical conditions. By analyzing the human hair, we can know stress levels on the human body and metabolic conditions caused by microgravity environment and cosmic radiation. The Japan Aerospace Exploration Agency (JAXA) has initiated a human research study to investigate the effects of long-term space flight on gene expression and mineral metabolism by analyzing hair samples of astronauts who stayed in the International Space Station (ISS) for 6 months. During long-term flights, the physiological effects on astronauts include muscle atrophy and bone calcium loss. Furthermore, radiation and psychological effects are important issue to consider. Therefore, an understanding of the effects of the space environment is important for developing countermeasures against the effects experienced by astronauts. In this experiment, we identify functionally important target proteins that integrate transcriptome, mineral metabolism and proteome profiles from human hair. To compare the protein expression data with the gene expression data from hair roots, we developed the protein processing method. We extracted the protein from five strands of hair using ISOGEN reagents. Then, these extracted proteins were analyzed by LC-MS/MS. These collected profiles will give us useful physiological information to examine the effect of space flight.

  14. Subtleties Concerning Conformal Tractor Bundles

    Graham, C Robin

    2012-01-01

    The realization of tractor bundles as associated bundles in conformal geometry is studied. It is shown that different natural choices of principal bundle with normal Cartan connection corresponding to a given conformal manifold can give rise to topologically distinct associated tractor bundles for the same inducing representation. Consequences for homogeneous models and conformal holonomy are described. A careful presentation is made of background material concerning standard tractor bundles and equivalence between parabolic geometries and underlying structures.

  15. Mycophenolate antagonizes IFN-γ-induced catagen-like changes via β-catenin activation in human dermal papilla cells and hair follicles.

    Ryu, Sunhyo; Lee, Yonghee; Hyun, Moo Yeol; Choi, Sun Young; Jeong, Kwan Ho; Park, Young Min; Kang, Hoon; Park, Kui Young; Armstrong, Cheryl A; Johnson, Andrew; Song, Peter I; Kim, Beom Joon

    2014-01-01

    Recently, various immunosuppressant drugs have been shown to induce hair growth in normal hair as well as in alopecia areata and androgenic alopecia; however, the responsible mechanism has not yet been fully elucidated. In this study, we investigate the influence of mycophenolate (MPA), an immunosuppressant, on the proliferation of human dermal papilla cells (hDPCs) and on the growth of human hair follicles following catagen induction with interferon (IFN)-γ. IFN-γ was found to reduce β-catenin, an activator of hair follicle growth, and activate glycogen synthase kinase (GSK)-3β, and enhance expression of the Wnt inhibitor DKK-1 and catagen inducer transforming growth factor (TGF)-β2. IFN-γ inhibited expression of ALP and other dermal papillar cells (DPCs) markers such as Axin2, IGF-1, and FGF 7 and 10. MPA increased β-catenin in IFN-γ-treated hDPCs leading to its nuclear accumulation via inhibition of GSK3β and reduction of DKK-1. Furthermore, MPA significantly increased expression of ALP and other DPC marker genes but inhibited expression of TGF-β2. Therefore, we demonstrate for the first time that IFN-γ induces catagen-like changes in hDPCs and in hair follicles via inhibition of Wnt/β-catenin signaling, and that MPA stabilizes β-catenin by inhibiting GSK3β leading to increased β-catenin target gene and DP signature gene expression, which may, in part, counteract IFN-γ-induced catagen in hDPCs. PMID:25247578

  16. Mycophenolate Antagonizes IFN-γ-Induced Catagen-Like Changes via β-Catenin Activation in Human Dermal Papilla Cells and Hair Follicles

    Sunhyo Ryu

    2014-09-01

    Full Text Available Recently, various immunosuppressant drugs have been shown to induce hair growth in normal hair as well as in alopecia areata and androgenic alopecia; however, the responsible mechanism has not yet been fully elucidated. In this study, we investigate the influence of mycophenolate (MPA, an immunosuppressant, on the proliferation of human dermal papilla cells (hDPCs and on the growth of human hair follicles following catagen induction with interferon (IFN-γ. IFN-γ was found to reduce β-catenin, an activator of hair follicle growth, and activate glycogen synthase kinase (GSK-3β, and enhance expression of the Wnt inhibitor DKK-1 and catagen inducer transforming growth factor (TGF-β2. IFN-γ inhibited expression of ALP and other dermal papillar cells (DPCs markers such as Axin2, IGF-1, and FGF 7 and 10. MPA increased β-catenin in IFN-γ-treated hDPCs leading to its nuclear accumulation via inhibition of GSK3β and reduction of DKK-1. Furthermore, MPA significantly increased expression of ALP and other DPC marker genes but inhibited expression of TGF-β2. Therefore, we demonstrate for the first time that IFN-γ induces catagen-like changes in hDPCs and in hair follicles via inhibition of Wnt/β-catenin signaling, and that MPA stabilizes β-catenin by inhibiting GSK3β leading to increased β-catenin target gene and DP signature gene expression, which may, in part, counteract IFN-γ-induced catagen in hDPCs.

  17. Auditory hair cell centrioles undergo confined Brownian motion throughout the developmental migration of the kinocilium.

    Lepelletier, Léa; de Monvel, Jacques Boutet; Buisson, Johanna; Desdouets, Chantal; Petit, Christine

    2013-01-01

    Planar polarization of the forming hair bundle, the mechanosensory antenna of auditory hair cells, depends on the poorly characterized center-to-edge displacement of a primary cilium, the kinocilium, at their apical surface. Taking advantage of the gradient of hair cell differentiation along the cochlea, we reconstituted a map of the kinocilia displacements in the mouse embryonic cochlea. We then developed a cochlear organotypic culture and video-microscopy approach to monitor the movements o...

  18. Solitary Hair Cells Are Distributed Throughout the Extramacular Epithelium in the Bullfrog's Saccule

    Gale, Jonathan E.; Meyers, Jason R.; Corwin, Jeffrey T.

    2000-01-01

    The frog inner ear contains eight sensory organs that provide sensitivities to auditory, vestibular, and ground-borne vibrational stimuli. The saccule in bullfrogs is responsible for detecting ground- and air-borne vibrations and is used for studies of hair cell physiology, development, and regeneration. Based on hair bundle morphology, a number of hair cell types have been defined in this organ. Using immunocytochemistry, vital labeling, and electron microscopy, we have characterized a new h...

  19. Shh is required for Tabby hair follicle development

    Cui, Chang-Yi; Kunisada, Makoto; Childress, Victoria; Michel, Marc; Schlessinger, David

    2011-01-01

    In embryonic Eda mutant (“Tabby”) mice, the development of one of the two major types of hair, “primary” hair fails, but other “secondary” hairs develop in normal numbers, though shorter and slightly aberrant. In Tabby mice, Shh is undetectable in skin early on, but is activated during secondary hair formation. We inferred that Shh may be involved in primary hair formation, activated normally by Eda, and also possibly in secondary hair formation, activated by an Eda-independent pathway. Varyi...

  20. Hair follicle dermal stem cells regenerate the dermal sheath, repopulate the dermal papilla, and modulate hair type.

    Rahmani, Waleed; Abbasi, Sepideh; Hagner, Andrew; Raharjo, Eko; Kumar, Ranjan; Hotta, Akitsu; Magness, Scott; Metzger, Daniel; Biernaskie, Jeff

    2014-12-01

    The dermal papilla (DP) provide instructive signals required to activate epithelial progenitors and initiate hair follicle regeneration. DP cell numbers fluctuate over the hair cycle, and hair loss is associated with gradual depletion/atrophy of DP cells. How DP cell numbers are maintained in healthy follicles remains unclear. We performed in vivo fate mapping of adult hair follicle dermal sheath (DS) cells to determine their lineage relationship with DP and found that a subset of DS cells are retained following each hair cycle, exhibit self-renewal, and repopulate the DS and the DP with new cells. Ablating these hair follicle dermal stem cells and their progeny retarded hair regrowth and altered hair type specification, suggesting that they function to modulate normal DP function. This work identifies a bipotent stem cell within the adult hair follicle mesenchyme and has important implications toward restoration of hair growth after injury, disease, and aging. PMID:25465495

  1. Hair dye poisoning

    Hair tint poisoning ... Different types of hair dye contain different harmful ingredients. The harmful ingredients in permanent dyes are: Naphthylamine Other aromatic amino compounds Phenylenediamines Toluene ...

  2. Pharmacologic interventions in aging hair

    Trüeb, Ralph M

    2006-01-01

    The appearance of hair plays an important role in people’s overall physical appearance and self-perception. With today’s increasing life-expectations, the desire to look youthful plays a bigger role than ever. The hair care industry has become aware of this and is delivering active products directed towards meeting this consumer demand. The discovery of pharmacological targets and the development of safe and effective drugs also indicate strategies of the drug industry for maintenance of heal...

  3. Assessment of protease activity in hydrolysed extracts from SSF of hair waste by and indigenous consortium of microorganisms.

    Yazid, Noraziah Abu; Barrena, Raquel; Sánchez, Antoni

    2016-03-01

    Hair wastes from the tannery industry were assessed for its suitability as substrates for protease production by solid-state fermentation (SSF) using a pilot-batch mode operation and anaerobically digested sludge as co-substrate. Maximum protease activity (52,230±1601Ug(-1)DM) was observed at the 14th day of SSF. Single step purification resulted in 2 fold purification with 74% of recovery by ultrafiltration with 10kDa cut-off. The recovered enzyme was stable at a temperature of 30°C and pH 11; optimal conditions that were determined by a central composite full factorial experimental design. The enzyme activity was inhibited by phenylmethylsulfonyl fluoride, which indicates that it belongs to serine protease group. The remaining solid material after protease extraction could be easily stabilized to obtain a final good quality compost-like material as the final dynamic respiration index was lower than 1gO2kg(-1)OMh(-1). The lyophilized recovered enzymes were a good alternative in the process of cowhides dehairing with respect to the current chemical treatment, avoiding the production of solid wastes and highly polluted wastewaters. In conclusion, the entire process can be considered a low-cost sustainable technology for the dehairing process, closing the organic matter cycle in the form of value added product and a compost-like material from a waste. PMID:26856443

  4. Hair Dyes Resorcinol and Lawsone Reduce Production of Melanin in Melanoma Cells by Tyrosinase Activity Inhibition and Decreasing Tyrosinase and Microphthalmia-Associated Transcription Factor (MITF) Expression

    Shu-Mei Lee; Yi-Shyan Chen; Chih-Chien Lin; Kuan-Hung Chen

    2015-01-01

    Hair coloring products are one of the most important cosmetics for modern people; there are three major types of hair dyes, including the temporary, semi-permanent and permanent hair dyes. The selected hair dyes (such as ammonium persulfate, sodium persulfate, resorcinol and lawsone) are the important components for hair coloring products. Therefore, we analyzed the effects of these compounds on melanogenesis in B16-F10 melanoma cells. The results proved that hair dyes resorcinol and lawsone ...

  5. The use of human hair as biodosimeter

    The potential use of human hair samples as biologic dosimeter was investigated by electron spin resonance (ESR) spectroscopy. The hair samples were obtained from female volunteers and classified according to the color, age and whether they are natural or dyed. Natural black, brown, red, blonde and dyed black hair samples were irradiated at low doses (5–50 Gy) and high doses (75–750 Gy) by gamma source giving the dose rate of 0.25 Gy/s in The Sarayköy Establishment of Turkish Atomic Energy Authority. While the peak heights and g-values (2.0021–2.0023) determined from recorded spectra of hair were color dependent, the peak-to-peak line widths were varied according to natural or dyed hair (ΔHpp: 0.522–0.744 mT). In all samples, the linear dose–response curves at low doses saturated after ∼300 Gy. In black hair samples taken from different individuals, differences in the structure of the spectrum and signal intensities were not observed. The EPR signal intensities of samples stored at room temperature for 22 days fell to their half-values in 44 h in black hair, 41 h in blonde and brown hairs, 35 h in dyed black hair and in 17 h in red hair. The activation energies of samples annealed at high temperatures for different periods of time were correlated well with those obtained in the literature. In conclusion, hair samples can be used as a biological dosimeter considering the limitations showed in this study. - Highlights: • Applied electron spin resonance spectroscopy to human hair used in biodosimetry. • Showed the limitations of hair samples using as a biological dosimeter. • Provided more systematic information on radiation-induced radicals in hair. • Found at least 3 different contributions in the RIS. That is the major finding of this work

  6. Pharmacological evaluation of Mallotus philippinensis (Lam. Muell.-Arg. fruit hair extract for Anti-Inflammatory, Analgesic and Hypnotic Activity

    Mayank Gangwar

    2016-03-01

    Full Text Available Recently we observed wound healing activity of 50% ethanol extract of Mallotus philippinensis Muell. Arg (MP fruit hairs extract (MPE. In several intestinal infections, localized inflammation is of common occurrence and hence we evaluated the anti-inflammatory, analgesic and hypnotic activity of MPE in different rat experimental models. Anti-inflammatory activity was evaluated by carrageenan (acute and turpentine oil induced formalin (subacute induced paw oedema and while, granuloma pouch (subacute in rats. Analgesic and hypnotic activity of MPE was undertaken by tail-flick, hot and ndash;plate and acetic acid-induced writhing tests while pentobarbitone-induced hypnotic potentiation respectively in rats.\tMPE at a dose of 200 mg/kg at 3 hr after their administration showed inhibition of formalin-induced paw oedema by 41.60% (P<0.001 and carrageenan-induced paw oedema by 55.30% (P<0.001. After 7 days of treatments, MPE showed 38.0% (P<0.001 inhibition against formalin-induced paw oedema and reduced weight of turpentine-induced granuloma pouch by 29.6% (P<0.01 and volume of exudates by 26.1% (P<0.01 respectively. MPE (200 mg/kg showed dose-dependent elevation in pain threshold and peak analgesic effect at 120 min as evidenced by increased latency period in tail flick method and increased reaction time in hot-plate test while reduction in the number of acetic acid-induced writhes by 45.7% (P<0.001. The pentobarbitone-induced hypnosis model showed potentiation, as defined by increased duration of sleep in treated group rats as compared to control. Thus, the study revealed MPE is effective in reducing acute and sub-acute inflammation and showed effective and similar analgesic activity. This seemed to be safe in the treatment of pain and inflammation. [J Intercult Ethnopharmacol 2016; 5(1.000: 14-21

  7. Right bundle branch block

    Bussink, Barbara E; Holst, Anders Gaarsdal; Jespersen, Lasse;

    2013-01-01

    AimsTo determine the prevalence, predictors of newly acquired, and the prognostic value of right bundle branch block (RBBB) and incomplete RBBB (IRBBB) on a resting 12-lead electrocardiogram in men and women from the general population.Methods and resultsWe followed 18 441 participants included in...... men vs. 0.5%/2.3% in women, P <0.001). Significant predictors of newly acquired RBBB were male gender, increasing age, high systolic blood pressure, and presence of IRBBB, whereas predictors of newly acquired IRBBB were male gender, increasing age, and low BMI. Right bundle branch block was associated...... with significantly increased all-cause and cardiovascular mortality in both genders with age-adjusted hazard ratios (HR) of 1.31 [95% confidence interval (CI), 1.11-1.54] and 1.87 (95% CI, 1.48-2.36) in the gender pooled analysis with little attenuation after multiple adjustment. Right bundle branch...

  8. Too much of a good thing: Long-term treatment with salicylate strengthens outer hair cell function but impairs auditory neural activity

    Chen, Guang-Di; Kermany, Mohammad Habiby; D’Elia, Alessandra; Ralli, Massimo; Tanaka, Chiemi; Bielefeld, Eric C.; Ding, Dalian; Henderson, Donald; Salvi, Richard

    2010-01-01

    Aspirin has been extensively used in clinical settings. Its side effects on auditory function, including hearing loss and tinnitus, are considered as temporary. A recent promising finding is that chronic treatment with high-dose salicylate (the active ingredient of aspirin) for several weeks enhances expression of the outer hair cell (OHC) motor protein (prestin), resulting in strengthened OHC electromotility and enhanced distortion product otoacoustic emissions (DPOAE). To follow up on these...

  9. Application of neutron activation analysis to evaluate the health status of equines by means of Cu, Fe, Mn and Zn determinations in their hair

    Instrumental neutron activation analysis (INAA) was applied to evaluate the clinical status of equines, belonging to the Military Police of Sao Paulo State, by means of Cu, Fe, Mn and Zn determinations in their hair. Comparison of the results obtained in these analyses with reference values indicated Zn deficiency in the equines, Fe is in the minimum limit and the elements Cu and Mn are within the normal range. (author)

  10. Principal -bundles on Nodal Curves

    Usha N Bhosle

    2001-08-01

    Let be a connected semisimple affine algebraic group defined over . We study the relation between stable, semistable -bundles on a nodal curve and representations of the fundamental group of . This study is done by extending the notion of (generalized) parabolic vector bundles to principal -bundles on the desingularization of and using the correspondence between them and principal -bundles on . We give an isomorphism of the stack of generalized parabolic bundles on with a quotient stack associated to loop groups. We show that if is simple and simply connected then the Picard group of the stack of principal -bundles on is isomorphic to ⊕ , being the number of components of .