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PubMed2003

Long-term follow-up and unusual findings after microvascular transfer of hair-bearing skin for pubic hair restoration.

Alopecia in the pubic area can be restored successfully with hair transplantation using minigrafts and micrografts or with free tissue transfer of a hair bearing flap. In this report the authors present the successful transfer of hair bearing tissue from the temporoparietal scalp for the correction of a congenital form of alopecia of the pubic region. In addition, they present long term results of this transfer. Auxiliary procedures such as tissue expansion before or after transferring the flap, hair epilation and minigraft and micrograft transplantation could help to achieve a more natural result. Tissue expansion of the donor site could also be performed to enhance the outcome of the procedure. Of note is the rapid rate of hair growth in the transplanted tissue. This type of reconstruction using a hair bearing temporoparietal flap for restoration of hair to the pubic region is a useful method that can yield good results.

Adult↗
PubMed1993

Hormones and hair growth: variations in androgen receptor content of dermal papilla cells cultured from human and red deer (Cervus elaphus) hair follicles.

Many hair follicles produce different types of hair in response to environmental changes or the mammals age, that are translated to the follicle by hormones. Androgens cause many changes, such as transforming vellus follicles producing insignificant hairs on the face to terminal beard ones at puberty or the reverse on the scalp. In male red deer the breeding season rise in androgens causes the annual production of a mane on the neck that is lost during the spring. Because the dermal papilla situated at the base of the hair follicle is important in determining the type of hair produced, androgens may act via the dermal papilla. Therefore, primary cell lines of dermal papilla cells from human and red deer follicles with different responses to androgens have been established. Specific saturable androgen receptors were present in all human papilla cells examined, with higher levels in cells from androgen-dependent follicles, e.g., beard than in control, non-balding scalp cells. In preliminary investigations of red deer, androgen receptors were only present in cells derived from mane follicles and were undetectable in flank or spring neck follicles. These similar results from both species support the hypothesis that androgens are acting on hair follicles via the dermal papilla. They also suggest that dermal papilla cells are potentially useful models for investigating the mechanism of androgen action because cultured cells appear to retain differences that relate to the androgen responsiveness of their parent follicle. The red deer seems particularly interesting in view of the much shorter hair-growth cycle than human scalp or beard follicles.

Adult↗
PubMed1994

Use of gamma-glutamyl transpeptidase activity as a marker of hair cycle and anagen induction in mouse hair follicles.

gamma-glutamyl transpeptidase activity was monitored in cycling mice by histologic localization and biochemical assay. Our objective for this study is to establish the relationship between gamma-glutamyl transpeptidase activity and hair growth and to determine whether its activity can be correlated to induced hair growth. In cycling mouse skin, gamma-glutamyl transpeptidase activity is pronounced during anagen and greatly diminished during telogen. In the skin, the enzyme is present exclusively in the outer and inner root sheaths of hair follicles. gamma-glutamyl transpeptidase is limited to the follicle below the level of the sebaceous gland and is completely absent in the follicle above the sebaceous gland level. During anagen, the outer root sheath in the hypodermis is intensely positive for gamma-glutamyl transpeptidase activity whereas the hair matrix cells and dermal papillar are negative. The inner root sheath above the bulb shows distinctive membrane staining for gamma-glutamyl transpeptidase. gamma-glutamyl transpeptidase activity can be seen to vary only in cycling follicles. Inducing anagen by plucking hair shafts results in an increase in gamma-glutamyl transpeptidase activity directly correlated to hair regrowth. In a similar manner, mice were plucked and treated with a daily dose of 2% minoxidil. A slight difference in cycle lengths was seen in animals treated with minoxidil when compared to vehicle control. Minoxidil treatment may cause an early initiation of anagen, but both the minoxidil-treated skin and the vehicle-treated skin entered telogen at the same time. Together, these studies indicate that gamma-glutamyl transpeptidase is a specific marker of anagen in growing hair.

Animals↗
PubMed1991

Metabolic studies on isolated hair follicles: hair follicles engage in aerobic glycolysis and do not demonstrate the glucose fatty acid cycle.

The matrix cells of the hair follicle have one of the highest rates of cell division in the mammalian body, but their fuel metabolism is poorly understood, due mainly to the difficulty in obtaining viable intact follicles from the skin. We have previously shown that viable and intact rat hair follicles can be isolated by shearing, and in this study we now report on their fuel metabolism. In this study we have shown that the hair follicle exhibits aerobic glycolysis, in that of the total glucose utilized by the hair follicle, only 10% is oxidized to CO2. We have also shown that, in the absence of glucose, the hair follicle is capable of utilizing other fuels such as palmitate and beta-hydroxybutyrate. However, neither palmitate or beta-hydroxybutyrate had any effect on the rate of glucose utilization or on [U-14C] glucose oxidation, showing that glucose sparing via the glucose fatty acid cycle does not operate in the hair follicle. Measurements of glucose flux through the pentose phosphate pathway accounted for only 3% of the total glucose utilized by the hair follicle, although this value represented 32% of the total glucose oxidized. Both palmitate and beta-hydroxybutyrate inhibited glucose flux through the pentose phosphate pathway.

3-Hydroxybutyric Acid↗
PubMed1989

Scanning electron microscopy comparing exclamation mark hairs in alopecia areata with normal hair fibres, mechanically broken by traction.

A scanning electron microscope was used to compare the distal ends of exclamation mark hairs from alopecia areata patients with the fracture surface of normal hair fibres, mechanically broken by traction. The exclamation mark hairs shows minimal damage to the cuticular cell pattern of the hair shaft. Where the cuticle was absent, cortex and medulla showed low-density features fanning out into a fringe-like structure at the distal ends. The fracture surfaces of normal hair fibres, mechanically broken by traction showed a markedly abnormal cuticular scale pattern, whereas the features of cortical and medullary tissue were normal. These morphological differences between the fracture surface of exclamation mark hairs and normal hair fibres, mechanically broken by traction, may enhance our understanding of the pathogenesis of alopecia areata.

Adult↗
PubMed1997

Chest hair used as donor material in hair restoration surgery.

BACKGROUND: This article describes a technique for transplanting hair from the chest to the balding scalp. OBJECTIVE: The objective is to describe an alternative route of harvesting donor hair in the situation when donor scalp hair is depleted. METHOD: A fusiform donor harvest was removed from the sternal region. The tissue was divided into one- and two-haired micrografts and subsequently transplanted. RESULTS: The technique worked extremely well with good take of the hair grafts. The donor site healed inconspicuously. CONCLUSION: The technique of transplanting hair from the chest to the balding scalp can be a viable alternative when confronted with donor scalp hair depletion.

Hair↗
PubMed2004

Recipient area hair direction and angle in hair transplanting.

BACKGROUND: A variety of recommendations for creating "natural" hair directions and angles in hair transplanting have been described. Objective. A method of accomplishing that goal is outlined. METHODS: Hair direction and angle are determined by multiple partings of the hair during the course of making recipient sites. Incisions are made to mimic such directions and angles. The direction is usually somewhat coronal and the use of grafts containing more than one follicular unit is particularly advantageous in producing a denser appearance. RESULTS: If the above technique is employed, one does not accelerate the rate at which existing hair in the recipient area is lost and the hair flows in a natural easy to manage fashion. CONCLUSION: Surgeons should nearly always mimic the scalp hair directions and angles seen in nature.

Hair Follicle↗
PubMed2005

Expression of CD1d in human scalp skin and hair follicles: hair cycle related alterations.

BACKGROUND: CD1d belongs to a family of antigen presenting molecules that are structurally and distantly related to the classic major histocompatibility complex class I (MHC I) proteins. However, unlike MHC I molecules, which bind protein antigens, CD1d binds to lipid and glycolipid antigens. CD1d is expressed by cells of lymphoid and myeloid origin, and by cells outside of the lymphoid and myeloid lineages, such as human keratinocytes of psoriatic skin. AIMS: To investigate whether CD1d is also expressed in sun exposed skin and in the immuno-privileged anagen hair follicle. MATERIALS/METHODS: CD1d immunoreactivity was studied in human scalp skin and hair follicles of healthy women in situ by immunofluorescent and light microscopic immunohistology. Skin biopsies were obtained from normal human scalp containing mainly anagen VI hair follicles from women (age, 53-57 years) undergoing elective plastic surgery. RESULTS: CD1d showed strong immunostaining in human scalp skin epidermis, pilosebaceous units, and eccrine glands. In the epidermis, CD1d was strongly expressed by basal and granular keratinocytes. In hair follicles, CD1d was expressed in the epithelial compartment and showed hair cycle related alterations, with an increase in the anagen and a reduction in the catagen and telogen phases. CONCLUSIONS: These results suggest that CD1d plays a role in human scalp skin immunology and protection against lipid antigen rich infectious microbes. They also raise the question of whether keratinocytes of the immuno-privileged anagen hair follicle can present lipid antigens to natural killer T cells. These data could help provide new strategies for the manipulation of hair related disorders.

Antigens, CD1↗
PubMed1995

Hair analysis for drugs of abuse. IX. Comparison of deprenyl use and methamphetamine use by hair analysis.

Deprenyl (DPN) and its metabolites, desmethyl deprenyl (desmethyl DPN), methamphetamine (MA) and amphetamine (AP), in the hair of rats and humans dosed with DPN were analyzed by selected ion monitoring of gas chromatograph-mass spectrometry (GC-MS-SIM). After intraperitoneal administration of DPN-HCl to rats (10 mg/kg/d, 10d, n = 3), the area under the concentration versus time curves (AUCs) of DPN and its metabolites in the rat plasma were compared with the concentrations of drugs in rat hair newly grown for 4 weeks. The concentrations of DPN, desmethyl DPN, MA and AP in the rat hair were 0.97 +/- 0.06, 0.68 +/- 0.02, 14.04 +/- 0.54 and 13.20 +/- 1.09 ng/mg, and the ratios of the concentrations in the hair to AUCs in their plasma were 0.05: 0.02: 0.3: 0.2, respectively. This fact suggested that the incorporation rates of DPN and desmethyl DPN into hair from blood were relatively lower than those of MA and AP. The method was applied to determination of the metabolites in scalp hair, beard and urine of humans who orally ingested DPN (15 mg/d, 5 d, n = 3). DPN (trace level), desmethyl DPN (0.17-0.29 ng/mg), MA (1.30-2.25 ng/mg) and AP (0.42-0.99 ng/mg) were detected in the scalp hair collected three weeks after the first intake, while in beard or urine these drugs were detected only for a few days.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗
PubMed2001

Hair analysis for pharmaceutical drugs. I. Effective extraction and determination of phenobarbital, phenytoin and their major metabolites in rat and human hair.

In order to establish an analytical method for the determination of phenobarbital (PB), phenytoin (PPH) and their hydroxylated metabolites in hair, animal model experiments were performed. Five male dark-agouti pigmented rats, aged 5 weeks, were intraperitoneally and orally administered PB or PPH independently at 25 mg/kg once a day for 5 successive days. The growing back hair was collected 15d after the first administration. Four typical extraction methods, using NH4OH-methanol-acetone, TFA-methanol-acetone, 1M sodium hydroxide and proteinase K, were evaluated using the rat hair samples containing PB or PPH. Methanol-acetone-NH4OH (10: 10: 1) was the best extraction method from all aspects, such as high extraction efficiency and low noise. The analytes in the extract were methylated in acetonitrile with 20% tetramethylammonium hydroxide and methyliodide at 70 degrees C for 10 min. After purification with Bond Elut Certify, the methylated products were analyzed by GC-MS. From rat hair, PB, p-hydroxy PB, PPH and p-hydroxy PPH were detected at average concentrations of 26.9, trace, 4.2 and 0.4 ng/mg with an intraperitoneal (i.p.) injection, and at 30.9, trace, 4.0 and 0.4 ng/mg with oral administration, respectively. There was little difference in hair concentrations between i.p. injection and oral administration. This method was applied to the head hair of two patients who orally took toxic amounts of PB and two volunteers who orally took 100 mg of PPH daily for 5 d. The hair concentrations of PB in the two patients were 16.2 and 14.7 ng/mg, and those of PPH in the two volunteers were 3.3 and 0.1 ng/mg.

Adult↗
PubMed2006

Depolarization of cochlear outer hair cells evokes active hair bundle motion by two mechanisms.

There is current debate about the origin of mechanical amplification whereby outer hair cells generate force to augment the sensitivity and frequency selectivity of the mammalian cochlea. To distinguish contributions to force production from the mechanotransducer (MET) channels and somatic motility, we have measured hair bundle motion during depolarization of individual outer hair cells in isolated rat cochleas. Depolarization evoked rapid positive bundle deflections that were reduced by perfusion with the MET channel blocker dihydrostreptomycin, with no effect on the nonlinear capacitance that is a manifestation of prestin-driven somatic motility. However, the movements were also diminished by Na salicylate and depended on the intracellular anion, properties implying involvement of the prestin motor. Furthermore, depolarization of one outer hair cell caused motion of neighboring hair bundles, indicating overall motion of the reticular lamina. Depolarization of solitary outer hair cells caused cell-length changes whose voltage-activation range depended on the intracellular anion but were insensitive to dihydrostreptomycin. These results imply that both the MET channels and the somatic motor participate in hair bundle motion evoked by depolarization. It is conceivable that the two processes can interact, a signal from the MET channels being capable of modulating the activity of the prestin motor.

Age Factors↗
PubMed2000

Active hair bundle motion linked to fast transducer adaptation in auditory hair cells.

During transduction in auditory hair cells, hair bundle deflection opens mechanotransducer channels that subsequently reclose or adapt to maintained stimuli, a major component of the adaptation occurring on a submillisecond time scale. Using a photodiode imaging technique, we measured hair bundle motion in voltage-clamped turtle hair cells to search for a mechanical correlate of fast adaptation. Excitatory force steps imposed by a flexible glass fiber attached to the bundle caused an initial movement toward the kinocilium, followed by a fast recoil equivalent to bundle stiffening. The recoil had a time course identical to adaptation of the transducer current, and like adaptation, was most prominent for small stimuli, was slowed by reducing extracellular calcium, and varied with hair cell resonant frequency. In free-standing hair bundles, depolarizations positive to 0 mV evoked an outward current attributable to opening of transducer channels, which was accompanied by a sustained bundle deflection toward the kinocilium. Both processes were sensitive to external calcium concentration and were abolished by blocking the transducer channels with dihydrostreptomycin. The similarity in properties of fast adaptation and the associated bundle motion indicates the operation of a rapid calcium-sensitive force generator linked to the gating of the transducer channels. This force generator may permit stimulus amplification during transduction in auditory hair cells.

Adaptation, Physiological↗
PubMed2001

Fatty acid ethyl esters in hair as markers of alcohol consumption. Segmental hair analysis of alcoholics, social drinkers, and teetotalers.

BACKGROUND: Fatty acid ethyl esters (FAEEs) are products of nonoxidative ethanol metabolism. After incorporation in hair, they should be suitable long-term markers of alcohol abuse. METHODS: Hair samples from 19 alcoholics in a treatment program, 10 fatalities with verified excessive alcohol consumption, 13 moderate social drinkers who consumed up to 20 g ethanol/day, and 5 strict teetotalers were analyzed in 1-12 segments for four FAEEs (ethyl myristate, ethyl palmitate, ethyl oleate, and ethyl stearate) by external degreasing with n-heptane, extraction with a dimethyl sulfoxide-n-heptane mixture, headspace solid-phase microextraction of the extracts, and gas chromatography-mass spectrometry with deuterated internal standards. The n-heptane washings were analyzed in the same way for FAEEs from the hair surface. RESULTS: The sum of the four ester concentrations in hair calculated for the proximal 0-6 cm segment was 2.5-13.5 ng/mg (mean, 6.8 ng/mg) for the fatalities, 0.92-11.6 ng/mg (mean, 4.0 ng/mg) for 17 of the alcoholics in treatment, 0.20-0.85 ng/mg (mean, 0.41 ng/mg) for the moderate social drinkers, and 0.06-0.37 ng/mg (mean, 0.16 ng/mg) for the teetotalers. In almost all cases the segmental concentrations increased from proximal to distal. There was no agreement between the self-reported drinking histories of the participants and the FAEE concentrations along the hair length. Ethyl oleate was the dominant ester in all samples. CONCLUSIONS: FAEEs are deposited in hair mainly from sebum. Despite large individual differences, FAEE hair concentrations can be used as markers for excessive alcohol consumption with relatively high accuracy.

Alcohol Drinking↗
PubMed2001

[New development of hair examination! The searching of hair for the terminal residual substance of pleasant sensation].

Formerly, hair had been analyzed mainly in the field of individual identification. Otherwise, it is known that many substances are accumulated in hair such as metals like arsenic, mercury, alkaloids like caffeine, theophylline, drugs like opiate, stimulants, other drugs and poisons. So, by qualitative and quantitative analysis of such deposits in hair. It is possible to presume one's life manner during recent several months. This is the new development of hair analysis and it is expected that it may be wide of application. The main theme of this paper is hedonics. Nobody dislike hedonic sensation. So, it can be said everybody being living always coveting hedonic sensation. There are many hedonic sensers all over the body, and hedonic sensation transmitted by A10 nerve, so A10 nerve is called the hedonic nerve. Neurotransmitter of this A10 nerve is Dopamine. Dopamine is the endogenous hedonic material. Exogeneous hedonic one is stimulant like Methamphetamine. In this paper, relation between Dopamine, Methamphetamine and Tyramine, thought to be the terminal product from two formers is examined in the aspect of hair analysis. Catecholamines including Dopamine are made of Tyrosine. They have a Benzene-ring. Compounds with a Benzene-ring made of Tyrosine are relatively rare, but all of them have very strong action. Tyramine is made of Tyrosine, too. So the structure of Tyramine is essentially resemble to Dopamine, and the skeletal structure of Methamphetamine is identical to Dopamine, so the action is identical, too. Normally, excessive release of Dopamine in brain is controlled by the negative feedback of GABA system. But extrinsic stimulus as Methamphetamine put balance of the homeostasis between Dopamine system and GABA system in to disorder, and long term administration of Methamphetamine makes long remaining degeneration of synapse of Dopamine nerve. So, abnormal state of excess releasing of Dopamine happens easily. And the morbid state named stimulant psychosis occur. The volume of Tyramine in hair changes correlatively with the volume of released Dopamine in brain. Therefore it is suggested that quantitative analysis of Tyramine in hair enable to estimate the changes of Dopamine released in brain.

Amphetamine↗
PubMedDate not supplied

A study of the photolightening mechanism of red hair with visible and ultraviolet light: comparison with blond hair.

The photolightening behavior of red hair was investigated. Red hair was found to lighten to a similar extent by irradiation from both ultraviolet (UV) and visible (VIS) light. Under the same irradiating conditions, blond hair was lightened by VIS light but did not lighten by UV light until it was washed after irradiation (1). These different photolightening behaviors of red and blond hair are supposed to be due to differences in their melanin compositions. The dominant type of melanin in red hair is pheomelanin; while blond hair investigated in the previous work contained both eumelanin and pheomelanin, with mainly eumelanin (2). Consequently, in this investigation, the photolightening behaviors of red and blond hair were compared to clarify the differences in photosensitivity between the two types of melanin.

Hair Color↗
PubMedDate not supplied

Hair breakage during combing. II. Impact loading and hair breakage.

During combing of hair, short fiber fragmentation (less than 2.5 cm) and longer segment breaks occur by different pathways. Longer fiber breaks most likely occur principally by impact loading. Impact loading causes hair breakage at lower loads than tensile loading, with essentially no increase in strain versus normal tensile testing, which produces large strain increases. Strain rates in impact loading are more similar to combing rates than rates of extension in tensile loading, and the looped and crossed hair formations in snags fit impact-load breakage better than simple extension of straight/non-crossed hairs in tensile testing. Extension or impacting hair fibers with flaws or damaged hair sections such as damaged wrapped ends produces short fiber fragmentation, while longer segment breaks may be produced in fibers with natural flaws such as fiber twists, cracks, or badly abraded or chemically weakened hair or even knots.

Equipment Design↗
PubMed1991

Hair analysis for drug abuse: I. Determination of methamphetamine and amphetamine in hair by stable isotope dilution gas chromatography/mass spectrometry method.

Determination of methamphetamine and amphetamine in hair was performed by gas chromatography/mass spectrometry using stable isotope-labeled internal standards, 2-methylamino-1-phenylpropane-2,3,3,3-d4 and 2-amino-1-phenylpropane-2,3,3,3-d4. Extraction of hair with methanol/5M hydrochloric acid (20:1) using ultrasonication was chosen as the standard method. The calibration curves for amphetamines in the hair were linear from 1 to 100 ng/mg (r greater than 0.99). The detection limit was 0.5 ng/mg at the 95% confidence level. The coefficients of variation (CV) (n = 8) of analysis using the spiked hair with methamphetamine were from 0.7 to 6%. The CV (n = 8) of analysis of the methamphetamine abuser's hair was 17.5%. Sectional analysis of monkey and human hair after methamphetamine ingestion suggested a good correlation between the duration of drug use and drug distribution in the hair.

Adult↗
PubMed1985

Hair zinc, scalp hair quantity, and diaper rash in normal infants.

Hair zinc concentration was determined by atomic absorption spectrophotometry in 308 normal newborn infants and 199 normal infants aged one to twelve months. Hair zinc concentration declined from 204 micrograms/gm at birth to 112 micrograms/gm at age eight months, and then rose to 144 micrograms/gm at age twelve months. Diaper rash was significantly associated with reduced hair zinc, and infants with the least hair had lower zinc levels than infants with the most hair. The data indicate that hair loss and diaper rash found in normal infants is significantly associated with a reduction in hair zinc concentration.

Diaper Rash↗