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PubMed2006

Female patients complaining about hair loss: documentation of defective scalp hair dynamics with contrast-enhanced phototrichogram.

BACKGROUND: The complaint of chronic hair loss frequently affects female subjects and there is little or no objective technology available in the general dermatology or even in the hair clinics to guide the observer in the management of the patient. The purpose of this report is to share the results of refined hair growth measurements that were collected in 92 female subjects complaining about hair loss. METHODS: Clinically they were classified as having a patterned hair loss according to Ludwig (L; n=50), diffuse hair loss (D; n=13) or no visible hair loss but complaining of hair shedding (N; n=29). Two scalp sites on the top of the head and one occipital site were investigated after clipping by close-up photography before and after a hair dye (contrast enhancement, CE). Forty-eight hours later a new photograph was taken after CE in view of phototrichogram analysis (CE-PTG). Finally a last hair clip was performed 30 days later and hair thickness and length determined for linear growth measurements (LHGR). RESULTS: Herein we confirm that the top of the head shows usually a higher hair density than occipital sites, a physiological observation that applies both to men and women. From the technological perspective, we also document that CE improves hair detection in all sites. Interestingly, in affected patients (L and D) the relative increase of hair counts after CE was much higher (range +22.4% to +28.3%) compared with apparently unaffected females (N; range +8.2% to +9.7%). This increase in hair counts was only due in part to the presence of less pigmented thinning hair (thickness less than 40 microm). Such thin hairs were found in statistically significantly higher proportions in younger patients with mildly severe (grade I) patterned alopecia (Ludwig: L). In other patients with hair loss and in more severe forms of patterned alopecia - especially in older patients - the thin hair is not detected in abnormal proportions. In all sites slower growth rates and decreased anagen percentages indicate a defective hair replacement programme distinguishing L patterns from diffuse hair loss and from apparently unaffected patients complaining of chronic hair loss. Globally, we also noted that increasing age is associated with significant regression of scalp hair (decreased hair counts, thinner hair and slower LHGR). CONCLUSION: On the basis of the present data together with female data from the literature and our own studies in male subjects, we suggest a three-step mechanism leading to hair loss 1. Shortening of growth phase the hair cycle with maintained thick hair, i.e. more frequent hair cycling that leads to more hair shedding. 2. Intermittent production of short thin hair, i.e. morphological evidence of miniaturisation. 3. Very occasional or almost no hair production, i.e. dormant follicles or irreversible follicular atrophy. Depending on the genetic background, hormonal microenvironment in the scalp and conditioning of individual hair follicle bio-responses, female and male patterned hair loss may end up into different phenotypes.

Alopecia↗

PubMedDate not supplied

The effect of hair color on the incorporation of codeine into human hair.

The influence of melanin on the binding of xenobiotics in hair will impact the interpretation of drug concentrations determined by hair testing. The purpose of this study was to determine if codeine, as a model compound of abused drugs, would be incorporated into black, brown, blond, or red hair as a function of melanin concentration. Such data would assist in the interpretation of codeine concentrations in hair and help elucidate the potential influence of hair color on incorporation of drugs. Male and female Caucasians with black (n = 6), brown (n = 12), blond (n = 8), or red hair (n = 6) and non-Caucasians with black hair (n = 12) aged 21-40 years were enrolled in the study. Each subject was administered oral codeine phosphate syrup in a dosage of 30 mg three times a day for five days. Twenty-four hours after the end of the treatment period, a 30-mg codeine dose was administered and the subject's plasma area under the concentration time curve (AUC) for codeine was determined. Codeine and melanin were measured in the first 3 cm of hair closest to the vertex region of the scalp prior to and 1, 4, 5, 6, and 7 weeks after dosing. The quantitative and qualitative melanin profiles were determined for each subject's hair to provide an objective measure of hair color. The plasma concentrations of codeine were measured to eliminate differences in the bioavailability and clearance of codeine as factors that might account for the differences in codeine hair concentrations. The subjects were asked not to cut their hair in the vertex region of the scalp or to use any form of chemical treatment on their hair, but otherwise normal hygienic measures were permitted. The mean (+/- SE) hair codeine concentrations 5 weeks after dosing were 1429 (+/- 249) pg/mg in black hair; 208 (+/- 17) pg/mg in brown hair; 99 (+/- 10) pg/mg in blond hair; and 69 (+/- 11) in red hair pg/mg. In black hair, codeine concentrations were 2564 (+/- 170) pg/mg for Asians and 865 (+/- 162) pg/mg for Caucasians. Similar concentration relationships were observed at weeks 4, 6, and 7. A strong relationship between the hair concentrations of codeine and melanin (R(2) = 0.73) was observed. Normalization of the codeine concentration with the melanin concentration reduced the hair color differences observed. These data demonstrate that the interpretation and reporting of hair test results for codeine are influenced by hair color. After this dosing protocol, the proposed federal guideline cutoff of 200 pg/mg of codeine would result in 100% of subjects with black hair and 50% of subjects with brown hair being reported as positive, and subjects with blond or red hair would be reported as negative. The incorporation of these drugs into hair should be studied carefully in humans to ensure the appropriate interpretation of drug concentrations.

Administration, Oral↗

PubMed1998

Fentanyl in hair. Chemical factors involved in accumulation and retention of fentanyl in hair after external exposure or in vivo deposition.

The levels of fentanyl extractable from mouse hair after chronic systemic administration and the suitability of externally loaded hair samples for establishing control and comparison samples were determined. Additionally, the effects of chemical modification of specific polar functionalities within the hair protein matrix on the deposition and recovery of fentanyl in hair subjected to external loading were determined. BALB/c mice entering a second phase of synchronized hair growth were treated ip with fentanyl (0.02, 0.05, or 0.10 mg/kg) on Monday, Wednesday, and Friday for 3 weeks. At that time, fentanyl concentrations in hair, as determined by GC/MS, were 0.025-0.050 ng/mg of hair. Hair samples exposed to fentanyl in phosphate buffer (ionized drug) showed no significant accumulation of drug into the hair, as determined by loss of fentanyl from the loading solution or by extraction of the hair. Hair samples exposed to nonionized fentanyl in methanolic solution (10, 50, and 100 ng/ml) showed significant accumulation of drug in the hair and significant removal of drug from the incubation solution. Fentanyl removal from solution plateaued after 24 hr, suggesting equilibration between fentanyl in solution and fentanyl in the hair. A mass balance between drug lost from the incubation solution and drug recovered from hair samples suggests that 94% of accumulated fentanyl is tightly bound to the hair matrix or resides in water-inaccessible compartments within the hair. These results suggest that fentanyl accumulation after in vivo administration differs, in the nature of storage, from fentanyl accumulation from external solutions and that external spiking of hair may not provide suitable control samples. Chemical modification of hair protein functionalities (reaction with diazomethane to esterify carboxylic acid groups or with acetic anhydride and pyridine to acetylate amine and hydroxyl functionalities) led to reproducible protein structure modification, as demonstrated by Fourier transform-IR and by pH titration. Hair from BALB/c mice was used. The accumulation of fentanyl was examined in hair samples exposed to fentanyl in methanol or methylene chloride solutions (10 ng/ml, 24 hr). Fentanyl was recovered from hair by 24-hr extraction in phosphate buffer, pH 6. Esterification of hair resulted in significantly less uptake of nonionized fentanyl from a methanolic solution and significantly lower recovery of drug from hair, relative to untreated hair, suggesting that carboxylic acid functionalities are necessary for the incorporation of drug. Acetylation of hair resulted in increased removal of fentanyl from methylene chloride solutions and increased recovery of fentanyl. This is consistent with the creation or expansion of a less polar compartment. Fentanyl uptake from a methanolic solution was also greater in acetylated hair. These results demonstrate that solution-accessible ionizable functionalities of hair play a significant role in the accumulation and retention of nonionized fentanyl from organic solutions.

Animals↗

PubMed2006

Characteristic features of Japanese women's hair with aging and with progressing hair loss.

BACKGROUND: There have been few studies of the features of hair with aging and hair loss in Japanese women. OBJECTIVE: Features of Japanese women's hair with aging and with progressing hair loss were investigated. METHODS: Japanese women with hair loss (n=46) or with no or less hair loss (n=113), aged 14-68 years, were studied. Severity of hair loss was rated by visual comparison with six standard photographs. Hair density, hair growth rate, and hair diameter were analyzed by phototrichogram. Follicular units were deduced by a non-invasive method using tree-view analysis on scalp imaging. RESULTS: Hair loss in Japanese women is commonly characterized by a diffuse central pattern occurring after approximately 40 years of age. Hair density declines with age after the 40s. The reduction resulted from an increase in the number of one-haired follicular units and a reduction of three- and more-haired follicular units. Both the ratio and the growth rate of anagen hair also declined with age after the 40s. Mean hair diameter and the ratio of thick hairs increased with age from about 10 to 40 years, and decreased with progressing hair loss. There were few vellus-like hairs in women with hair loss, in comparison with male-pattern baldness. CONCLUSION: In Japanese middle-aged women, hair density declined with age without the appearance of hair loss. Hair loss appeared after approximately 40 years of age. The major causes might be reduction of hair density and the ratio of thick hairs, but not an increase of vellus-like hairs.

Adolescent↗

PubMed2003

Overexpression of skin protein kinase C-alpha in anagen hair follicles during induced growth of mouse hair.

A role for protein kinase C (PKC)-alpha has been implicated in the growth of mouse hair. Topical application of PKC activators, hair plucking, allergic contact dermatitis and skin irritation can all enhance growth of mouse hair, and a significant increase in PKC-alpha level in whole mouse skin in mature anagen has been demonstrated in these processes. Overexpression of PKC-alpha in anagen hair follicles has also been reported in natural growth of mouse hair. It is known that overexpression of PKC-alpha is associated with the acceleration of cell growth. Therefore, we postulated that overexpression of PKC-alpha in mature anagen may relate to enhancement of hair growth. The distribution of PKC-alpha in hair follicles during induced growth of mouse hair has not previously been studied. In this study, hair growth in C57BL/6 mice was induced by plucking the telogen hairs on one side of the back. The undepilated contralateral side served as a control. Expression of PKC-alpha in hair follicles during the hair growth cycle induced was evaluated by immunohistochemistry using cryosections and a specific polyclonal anti-PKC-alpha immunoglobulin G (IgG) antibody. No PKC-alpha was detected in telogen hair follicles or in the hair follicles at 1 day post-depilation, when the induced hair cycle was in early anagen. At 4 days after plucking, when the induced hair cycle was in mid-anagen, intense staining for PKC-alpha was found in hair papillae. At 10 and 17 days after depilation, when the induced hair cycle was in mature anagen and early catagen, respectively, all outer root sheath (ORS) cells and outer connective sheaths of hair follicles were stained positive. Because no PKC-alpha was detected in telogen hair follicles in this study, down-regulation of PKC-alpha in early anagen could not be observed. However, consistent with our previous findings, overexpression of PKC-alpha was found in mid-anagen and mature anagen. As overexpression of PKC-alpha has been shown to be associated with acceleration of cell growth, our results support the notion that PKC-alpha may play an important role in growth of hair follicle cells in induced growth of hair. As PKC levels are known to increase in hyperglycaemia, overexpressed PKC-alpha in mature anagen hair follicles may be related to the putative function of the ORS in mobilizing glycogen stores for anagen growth.

Administration, Topical↗

PubMed2004

Hair cycle and hair pigmentation: dynamic interactions and changes associated with aging.

The tight coupling of hair follicle melanogenesis to the hair growth cycle dramatically distinguishes follicular melanogenesis from the continuous melanogenesis of the epidermis. Cyclic re-construction of an intact hair follicle pigmentary unit occurs optimally in all scalp hair follicles during only the first 10 hair cycles, i.e. by approximately 40 years of age. Thereafter there appears to be a genetically regulated exhaustion of the pigmentary potential of each individual hair follicle leading to the formation of true gray and white hair. Pigment dilution results primarily from a reduction in tyrosinase activity within hair bulbar melanocytes. Thereafter, sub-optimal melanocyte-cortical keratinocyte interactions, and defective migration of melanocytes from a reservoir in the upper outer root sheath to the pigment-permitting microenvironment close to the follicular papilla of the hair bulb, will all disrupt normal function of the pigmentary unit. Evidence from studies on epidermal melanocyte aging suggest that reactive oxygen species-mediated damage to nuclear and mitochondrial DNA may lead to mutation accumulation in bulbar melanocytes. Parallel dysregulation of anti-oxidant mechanisms or pro/anti-apoptotic factors is also likely to occur within the cells. Pigment loss in canities may also affect keratinocyte proliferation and differentiation, providing the tantalizing suggestion that melanocytes in the hair follicle contribute far more that packages of pigment alone. Here, we review the current state of knowledge of the development, regulation and control of the aging human hair follicle pigmentary system in relation with hair cycling. The exploitation of recently available methodologies to manipulate hair follicle melanocytes in vitro, and the observations that melanocytes remain in senile white hair follicles that can be induced to pigment in culture, raises the possibility of someday reversing canities. The perspective of rejuvenation of the whole hair follicle apparatus are still part of the dream but optimising its functional properties is clinically relevant and is close to reality. Finally as hair color influences its visibility when optical methods such as scalp photography are used to count hair fibers, the attention is drawn to possible interpretations of statistically significant changes in visible hair. Such changes may not exclusively be related to improved hair growth itself but also to changes in natural hair color that makes the hair more visible with the method used to count hairs.

Adult↗

PubMed2004

Body hair scores and total hair diameters in healthy women in the Kirikkale Region of Turkey.

It was aimed to determine the normal hair scores of women of Kirikkale region according to the Ferriman- Gallwey scale and to investigate the relationship between the hair shaft diameter and hair scores. Hair scores were calculated in 204 healthy women, and hair shaft diameters were measured from the hair samples collected from 60 patients. Body mass index, waist to hip ratio, insulin resistance and blood androgen levels were determined. Neutral, hormonal and total hair scores were 2.1 1.4, 3.1 2.7 and 5.2 3.6, respectively. The average total hair diameter and hormonal hair diameter were 191.93 90.49 m and 121.8 75.9 m respectively. The correlation between total hair diameter and total hair score was statistically significant (r=0.704 p 0.001). Also, the correlation between hormonal hair diameter and hormonal hair score was statistically significant (r=0.724 p 0.001). While hair scores and diameters show meaningful positive correlation with androgen levels, they show negative correlation with age. In our population, 95% value of total hair score was 11, and for the hormonal score, it was 9. Hair diameters increase with hair score, regardless of total or hormonal of hair scores. Hair scores and hair diameters may be affected by blood androgens in healthy women.

Acne Vulgaris↗

PubMed2005

Hair loss: is there a relationship with hair care practices in Nigeria?

BACKGROUND Hair loss occurs in all ethnic populations, but the etiology varies considerably from group to group. In black women, many forms of alopecia are associated with hair care practices. However, the causes of alopecias in African women have not been extensively investigated. OBJECTIVE This descriptive, cross-sectional, hospital-based study was undertaken to document common complaints on initial presentation for hair loss, hair care practices and patterns of hair loss, and to determine if there is a relationship between hair loss and hair care practices. METHODS A total of 39 female patients seen over a 12 month period were enrolled in the study. Demographic information recorded included age, sex, marital status and occupation. Information regarding medical history included initial presenting complaints, duration of hair loss, site of hair loss, whether there was skin or systemic involvement, hair care practices and the duration of these practices. Examination of the scalp, a hair-pull test, documentation of the pattern of hair loss, relevant laboratory tests and biopsies were carried out. RESULTS All 39 patients were adults. Major complaints at initial presentation, apart from hair loss, included itchy scalp in 17 patients (43.6%), painful scalp in 11 patients (28.2%), hair breakage in seven patients (17.9%) and flaking scalp in four patients (10.3%). All the women relaxed their hair at some point in time. Chemical relaxants were consistently used by 22 patients (53.7%), eight patients (20.5%) alternated these with plaits/braids, and nine patients (23.1%) wore extensions. The use of local concoctions in hair care management was reported by three patients (7.7%). Scarred alopecias were observed in 20 patients (51.3%), while 19 (48.7%) had non-scarred alopecias. Those who reported prolonged and frequent use of chemical relaxants [mean duration (+/- standard deviation) 23.2+/-9.3 years] exhibited scarred alopecia more commonly than those who did not often use chemical relaxants (P<0.001). The application of local concoctions or pomades was also a regular practice amongst females with scarred alopecias. CONCLUSIONS Itchiness, pain, ready hair breakage and flaking scalp were common complaints at initial presentation. A range of alopecias were documented, and it was also observed that duration of hair care practice and hair styling were relevant to hair loss, particularly for women with central centifugal cicatricial alopecias (CCCAs), which resulted in scarring.

Adolescent↗

PubMed1998

Hair analysis for drugs of abuse XX. Incorporation and behaviors of seven methamphetamine homologs in the rat hair root.

To elucidate drug disposition in hair, the incorporation and retention behavior of 7 phenethylamines in the rat hair root were investigated: methamphetamine(MA), 3,4-methylenedioxymethamphetamine(MDMA), benzphetamine(BZP), ephedrine(EP), N,N-dimethylamphetamine(DMA), p-nitro-methamphetamine(NO2MA), and N-acetylmethamphetamine(AcMA). On day 10 after shaving the hair on the back of the rats, drug was intraperitoneally administered at a single dose of 10 mg/kg to Long Evans rats (which were male and 6 weeks of age), possessing black and white hair, and the back hair that grew was collected by plucking with hair nippers at 0.083 h (5 min), 0.25 h, 0.5 h, 1 h, 2 h, 4 h, 6 h, 9 h, 24 h, 33 h and 48 h. After washing the plucked hairs three times with 0.1% sodium dodecylsulfate, the amount of drug in each of the hair root samples was analyzed by a selected ion monitoring of gas chromatography mass spectrometry (GC-MS) analysis. The times at which the concentration of each drug in the hair root samples reached the peak concentration, ranged between 3.30 and 41.51 ng/mg. For each drug, the point of time at which the largest positive incremental change in drug concentration was seen, ranged between 5 min and 1 h, for all of the drugs except for AcMA which was hardly incorporated in the rat hair. The data showed that there are mainly 4 modes in which a drug becomes incorporated into the black hair root: rapid and prolonged incorporation (NO2MA, MDMA), rapid and short incorporation(MA, DMA), slow and prolonged incorporation(BZP, EP), slow and short incorporation, which includes hardly any incorporation (AcMA). As all seven drugs were hardly incorporated into the white hair, it was concluded that the combination of melanin and basic compounds is essential for a drug to become incorporated into hair. Our results suggest that a portion of the drugs in the hair root is accumulated in the hair shaft, and the remaining portion is redistributed outside the hair shaft. The second finding is that the concentration of drug incorporated into hair mainly depends on two processes--(1) the drug incorporation into hair and the drug retention in hair.

Animals↗

PubMed1999

The catalog of human hair keratins. I. Expression of the nine type I members in the hair follicle.

The human type I hair keratin subfamily comprises nine individual members, which can be subdivided into three groups. Group A (hHa1, hHa3-I, hHa3-II, hHa4) and B (hHa7, hHa8) each contains structurally related hair keratins, whereas group C members hHa2, hHa5, and hHa6 represent structurally rather unrelated hair keratins. Antibodies produced against these individual hair keratins, first analyzed for specificity by one- dimensional Western blots of total hair keratins, were used to establish the two-dimensional catalog of the human type I hair keratin subfamily. The catalog comprises two different series of type I hair keratins: a strongly expressed, Coomassie-stainable series containing hair keratins hHa1, hHa3-I/II, hHa4, and hHa5, and a weakly expressed, immunodetectable series harboring hHa2, hHa6 hHa7, and hHa8. In situ hybridization and immunohistochemical expression studies on scalp follicles show that two hair keratins, hHa2 and hHa5, define the early stage of hair differentiation, i.e. hHa5 expression in hair matrix and hHa5/hHa2 coexpression in the early hair cuticle cells. Whereas cuticular differentiation proceeds without the expression of further type I hair keratins, matrix cells embark on the cortical pathway by sequentially expressing hHa1, hHa3-I/II, and hHa4, which are supplemented by hHa6 at an advanced stage of cortical differentiation, and hHa8, which is expressed heterogeneously in cortex cells. Thus, six type I hair keratins are involved in the terminal differentiation of anagen hairs. The expression of hHa7 is conspicuously different from that of the other hair keratins in that it does not occur in the large anagen follicles of terminal scalp hairs but only in central cortex cells of the rare and small follicle type that gives rise to vellus hairs.

Blotting, Western↗

PubMed1996

In vitro binding studies of drugs to hair: influence of melanin and lipids on cocaine binding to Caucasoid and Africoid hair.

Although the mechanism(s) of drug deposition in hair are unknown, there is evidence that suggests that the amount and type of melanin present are major factors in determining how much drug enters hair after exposure. The role of other hair components, such as lipids, has received less attention. We used in vitro binding techniques to evaluate the binding of radiolabeled cocaine to different types of treated and untreated hair specimens. Divided male and female Caucasoid (black/brown and blond colored) and Africoid (black colored) hair specimens (N = 7) were exhaustively extracted to remove lipid components (lipid-extracted hair). Separate portions were bleached to denature or alter melanin content. Experiments with radiolabeled cocaine were performed on untreated, lipid-extracted, and bleached portions of hair from different groups. Cocaine binding was significantly higher (p < .01) to male Africoid hair compared with other groups. The amount of drug binding was similar among female Africoid and male and female, black/brown Caucasoid specimens. The lowest amount of binding was observed with blond, female Caucasoid specimens. Binding experiments also revealed that specific cocaine binding generally did not differ significantly between lipid-extracted hair and untreated hair, but bleaching of most hair specimens resulted in significant (p < .01) decreases in specific binding compared with untreated hair. In separate experiments with cocaine-treated hair specimens, digested samples were evaluated to determine if removal of the insoluble melanin fraction from soluble hair components provided a means of normalization of drug content and elimination of color bias. Removal of the insoluble melanin fraction was not effective in removal of significant amounts of cocaine, which indicated that the digestion process released bound cocaine into the digest solution. Overall, these experiments suggested that lipids in hair play a minor role in drug binding, whereas melanin functions as a major binding site for cocaine. Natural (ethnic) or artificial (bleaching) differences in melanin content may determine the extent of cocaine entrapment in hair after drug exposure. Further, digestion of hair samples and removal of insoluble melanin failed to be effective in removal of hair color bias.

Analysis of Variance↗

PubMedDate not supplied

Determination of endogenous levels of GHB in human hair. Are there possibilities for the identification of GHB administration through hair analysis in cases of drug-facilitated sexual assault?

We have developed a GC-MS-MS assay for GHB in human hair. Five milligrams of washed hair were hydrolyzed by 1M or 0.01M NaOH before a liquid-liquid extraction with ethyl acetate under acidic conditions. GHB-d(6) was used as the internal standard. TMS derivatives were formed before injection. TBDMS derivatives were used in cases of strong chromatographic interferences or in a confirmatory procedure. Analysis of basal levels of GHB in 61 drug-free donors gave the following results: the mean measured concentration for blond hair was 0.60 ng/mg (n = 12), SD = 0.19 ng/mg, and extreme figures were in the range 0.35-0.95 ng/mg. For brown hair, the mean measured concentration was 0.90 ng/mg (n = 30), SD = 0.42 ng/mg, and extreme figures 0.41-1.86 ng/mg. For black hair, the mean measured concentration was 0.90 ng/mg (n = 19), SD = 0.37 ng/mg, and extreme figures 0.32-1.54 ng/mg, showing no significant differences depending on hair color. Analysis of basal levels of GHB of 12 or more specimens in segmented hair showed a mean concentration of 1.22 ng/mg (0.31-8.4 ng/mg) and a relative standard deviation for each individual ranging from 6.75% to 37.98%. GHB was administered to a healthy 53-year-old white male (light brown hair) at oral dosages of 30, 45, and 60 mg/kg. Beard hair was collected just before administration and 24 h after (and each day for one week for the last dose), and a 7.5-cm scalp hair lock was collected 7 days after the last dose. A rise in GHB concentration was observed in beard hair for the 45 and 60 mg/kg dosages with a maximum at 24 h, whereas no change was observed for the 30 mg/kg dosage. Scalp hair was segmented into 3-mm long segments. The three proximal last segments showed significantly (0.0005 < p < 0.005) different concentrations of GHB (1.22, 1.27, and 1.66 ng/mg, respectively) when compared with the basal physiological level of GHB in this same person (mean = 0.62 ng/mg, SD = 0.15 ng/mg). A case of daily GHB abuse during bodybuilding allowed us to determine a concentration of GHB of 14 ng/mg, in a 2-cm long segment (black hair). A case of rape under the influence of GHB was documented through hair analysis (black hair) and positive analysis of the glass she used. Sampled 7 days after the sexual assault, the three last 3-mm long proximal segments tested for GHB exhibited concentrations of 3.1-5.3 and 4.3 ng/mg, respectively, whereas the mean physiological level determined in this woman was 0.71 ng/mg, SD = 0.17 ng/mg. The authors advise a two-step hair sampling as evidence of GHB consumption: the first sample at the time of exposure to show the contamination by sweat of the proximal segment in case of recent administration with a significant rise of hair level at the root, and the second after at least 3 or 4 weeks to avoid this contamination and determine the levels incorporated in the hair matrix before, during, and after the exposure.

Dose-Response Relationship, Drug↗

PubMed2006

Hair analysis of histamine and several metabolites in C3H/HeNCrj mice by ultra performance liquid chromatography with electrospray ionization time-of-flight mass spectrometry (UPLC-ESI-TOF-MS): influence of hair cycle and age.

BACKGROUND: According to a previous study, the concentration of HA in the hair of SD rats was similar in each rat and the variation in HA concentration was not so great. However, the concentration in human hair was fairly different in each person. As possible reasons for the higher variation in human hair, the differences in hair cycles and age in each person may be considerable. Based on this idea, the studies using C3H/HeNCrj mice who can synchronize their hair cycle were performed for resolution of the influence of hair cycle and age. METHODS: The effects of hair cycle and age on the concentration of histamine (HA) and several metabolites, i.e., 1-methylhistamine (MHA), imidazole-4-acetic acid (IAA), and 1-methyl-4-imidazole-acetic acid (MIAA), in C3H/HeNCrj mice hair were investigated by ultra-performance liquid chromatography (UPLC) with electrospray ionization time-of-flight mass spectrometry (ESI-TOF-MS). HA and the metabolites were labeled with 4-(N,N-dimethylaminosulfonyl)-7-fluoro-2,1,3-benzoxadiazole (DBD-F) and 4-(N,N-dimethylaminosulfonyl)-7-piperazino-2,1,3-benzoxadiazole (DBD-PZ). The resulting derivatives were separated by UPLC and determined with ESI-TOF-MS. RESULTS: A good linearity was achieved from the calibration curves, obtained by plotting the peak area ratios of the analytes relative to the internal standard (IS), i.e., histamine-alpha,alpha,beta,beta-d4 (HA-d4) or 4-imidazolecarboxylic acid (ICA), against the injected amounts of each compound. The detection limits of HA, MHA, IAA, and MIAA on mass chromatograms were 0.21, 1.0, 0.17, and 0.11 pmol, respectively. The concentrations of HA and the metabolites in the hair shafts and hair root of C3H/HeNCrj mice were determined by this method. The concentration of HA in the hair shaft was relatively higher in the telogen phase. In contrast, the HA content in the anagen phase was increased only in the hair root of old mice. CONCLUSION: HA appears to possess some effect on hair growth, although the exact reason was not obvious. The HA metabolites, i.e., MHA, MIAA and IAA, were also determined the same as HA; however, the difference in the metabolite concentrations between the hair cycle and age was not clear in both hair shaft and hair root. Such studies of the effect of hair cycle and age on these concentrations are the first report. This analytical technique may be applicable to the determination of various biological compounds in hair.

Age Factors↗

PubMed1993

Regulation of hair follicle development: an in vitro model for hair follicle invasion of dermis and associated connective tissue remodeling.

During embryonic development presumptive hair follicle cells of epithelial and mesenchymal origin are determined in defined body locations. This is followed by rapid proliferation of epithelial cells and associated penetration into the dermis in response to as yet undetermined signals. A collagen matrix culture system, which maintains the three-dimensional relationships of hair follicle cells to each other, was developed to study the regulation of the enlargement of immature hair follicles and the accompanying remodeling of the dermis. In studies with a heterogeneous dermis-derived preparation of murine hair follicles, ranging in size from the earliest down-growing budding cell mass to hair-forming follicles, we had previously shown that cell proliferation was stimulated by cholera toxin and epidermal growth factor, but only the epidermal growth factor-stimulated proliferation was accompanied by digestion of the collagen matrix due to release of collagenolytic enzymes. Further studies revealed that transforming growth factor-alpha also stimulated hair follicle cell proliferation and collagenase release. However, although transforming growth factor-beta inhibited the transforming growth factor-alpha-stimulated proliferation, it enhanced the release and activation of collagenases and other gelatin-degrading enzymes detectable by gelatin zymography. Stimulation of collagenolytic activity depended on the three-dimensional hair follicle structure and did not occur in monolayer cultures of hair follicle cells. Comparison of hair follicle buds with more developed dermis-derived hair follicles, plated at the same cell density (based on DNA content), suggested that a greater fraction of cells in the bud-stage follicle responded to the growth factors by release of collagenases. Possibly only the cells in the advancing portion of growing hair follicles that are closest to the dermal papilla cell cluster produce the collagenases in response to growth factors. To examine the participation of dermal papilla cells in collagenase release and activation, several immortalized rat whisker dermal papilla cell lines were co-cultured with mouse hair follicle buds. Co-culture resulted in a marked enlargement of follicles as well as activation of the 92-kDa type IV collagenase, produced by hair follicle buds, that correlated with ability of the dermal papilla cells to stimulate hair formation in grafts of hair follicle buds on nude mice. Dermal papilla cells cultured alone produced the 72-kDa type IV collagenase, which was also activated during co-culture with hair follicle buds. Thus, two activities, both relevant for hair follicle development, namely, cell proliferation and release and activation of collagenases, have been stimulated in immature hair follicle buds by either growth-factor supplementation or interaction with dermal papilla cells.(ABSTRACT TRUNCATED AT 400 WORDS)

3T3 Cells↗

PubMed2004

Human hair greying is linked to a specific depletion of hair follicle melanocytes affecting both the bulb and the outer root sheath.

BACKGROUND: Although hair greying is a very common phenomenon characterized by loss of pigment in the hair shaft, the events that cause and control natural hair whitening with age in humans are still unclear. OBJECTIVES: To decipher the origin of natural hair whitening. METHODS: Human hair melanocytes were immunohistochemically characterized at different stages of whitening. RESULTS: Loss of hair shaft melanin was found to be associated with a decrease in both bulb melanin content and bulb melanocyte population. Although few melanocytes were present in the bulbs of grey hair, they still expressed tyrosinase and tyrosinase-related protein-1, synthesized and transferred melanins to cortical keratinocytes as seen by the presence of melanin granules. In white hair bulbs, no melanocytes could be detected either with pMel-17 or vimentin labelling. Pigmented hair follicles are known to contain inactive melanocytes in the outer root sheath (ORS), and grey and white hairs were also found to contain some of these quiescent melanocytes. However, their population was decreased compared with pigmented hair follicles, ranging from small to nil. This depletion of melanocytes in the different areas of white hairs was detected throughout the hair cycle, namely at telogen and early anagen stages. In contrast, the infundibulum and sebaceous gland of both pigmented and white hairs showed a similar distribution of melanocytes. Furthermore, other distinct cell populations located in the ORS, namely putative stem cells, Merkel cells and Langerhans cells were equivalently identified in pigmented and white hairs. CONCLUSIONS: Thus, hair greying appears to be a consequence of an overall and specific depletion of bulb and ORS melanocytes of human hair.

Adult↗

PubMed1999

Ruby laser-assisted hair removal reduces the coarseness of regrowing hairs: fallacy or fact?

There have been anecdotal reports that hairs that regrow after ruby laser-assisted hair removal are finer in appearance. If true, this phenomenon adds to the improved aesthetic effect of laser treatment of unwanted hair. It is the aim of this study to determine whether this phenomenon indeed occurs, and if so, assess its permanence and its mode of action. In this prospective clinical study, 71 patients with 94 treatment sites were treated with the Chromos 694 Depilation Ruby Laser. Hair diameter was measured pre-treatment, and at 3 and 7 months post-treatment. In addition, ex vivo scalp skin was used to assess if the ruby laser selectively damaged coarser hairs. Laser-treated and matched untreated skin samples were histologically assessed and the diameters of hair shafts (normal or obviously damaged) were measured. Results of this study were analysed using Kruskal-Wallis one-way analysis. There was no statistically significant difference between the hair diameter of non-lasered specimens and the hair diameter of the normal hair in lasered specimens. However, a statistically significant difference was seen between the hair diameter of non-lasered specimens and diameters of damaged hair in lasered specimens (P < 0.05). There was a statistically significant difference (P < 0.05) between pre-treatment and 3 month hair diameters, but no statistically significant difference was found between pre-treatment and 7 month hair diameters. In conclusion, ruby laser-assisted hair removal results in a temporary reduction in hair diameter of regrowing hair. This is not due to the selective targeting of larger hair follicles.

Adolescent↗

PubMed1983

Serial section reconstruction of the neural poles of hair cells in the human organ of Corti. II. outer hair cells.

Study of the anatomy of the cochlea, and in particular the morphology of synaptic relationships between hair cells and cochlear neurons, is essential for elucidation of the mechanisms of transduction of mechanical acoustic signals into electrical neural events. Because considerable gaps remain in our understanding of the microscopic anatomy of these synapses, particularly in the human, a reconstruction of the neural pole of outer hair cells of the human organ of Corti was performed. The data are based on 577 serial sections from the basal turn and 368 sections from the middle turn. This provided complete data on 11 and partial data on 9 outer hair cells. Terminal size of afferent fibers on outer hair cells was much more uniform than that found at the base of inner hair cells. Only small bouton-like terminals were found. Branching of afferent fibers was also seen at the base of outer hair cells. Each outer hair cell received approximately two to eight afferent nerve terminals. Multiple synaptic contacts between a single afferent terminal and an outer hair cell were common. Junctional membrane specialization consisted of synapses, desmosomes, coated vesicles and arrays of microtubules and membrane cisternae. Specialization at synapses consisted of asymmetrical membrane thickening. At outer hair cells the presynaptic membrane was thicker than the postsynaptic membrane. At inner hair cells the converse was true. At outer hair cells 35% of synapses had presynaptic bodies, compared to 83% of synapses at inner hair cells. Reciprocal synapses, with both hair cell to neuron and neuron to hair cell polarities, were found only on outer hair cells. Vesiculated efferent terminals were common at the base of outer hair cells. Both axosomatic and axodendritic efferent synapses were found. In addition, the same efferent fibers were found to synapse both on an outer hair cell and on an afferent dendrite. One example of a probable dendro-dendritic synapse in the outer spiral bundle is presented.

Cochlear Nerve↗

PubMed2002

Hair cell development in vivo and in vitro: analysis by using a monoclonal antibody specific to hair cells in the chick inner ear.

The purpose of this study was to establish a hair cell-specific marker and a convenient explant culture system for developing chick otocysts to facilitate in vivo and in vitro studies focusing on hair cell genesis in the inner ear. To achieve this, a hair cell-specific monoclonal antibody, 2A7, was generated by immunizing chick inner ear tissues to a mouse. Through the use of immunofluorescence and immunoelectron microscopy, it was shown that 2A7 immunoreactivity (2A7-IR) was primarily restricted to the apical region of inner ear hair cells, including stereocilia, kinocilia, apical membrane amongst the extending cilia, and superficial layer of the cuticular plate. Although the 2A7 antibody immunolabeled basically all of the hair cells in the posthatch chick inner ear, two different patterns of 2A7-IR were observed; hair cells located in the striolar region of the utricular macula, which consist of two distinct cell types identifiable on the basis of the type of nerve ending, Type I and II hair cells, showed labeling restricted to the basal end of the hair bundles. On the other hand, hair cells in the extrastriolar region, which are exclusively of Type II, showed labeling extending over virtually the entire length of the bundles. These findings raised the possibility that chick vestibular Type II hair cells, characterized by their bouton-type afferent nerve endings, can be divided into two subpopulations. Analysis of developing inner ear by using the 2A7 antibody revealed that this antibody also recognizes newly differentiated immature hair cells. Thus, the 2A7 antibody is able to recognize both immature and mature hair cells in vivo. The developmental potential of embryonic otocysts in vitro was then assessed by using explant cultures as a model. In this study, conventional otocyst explant cultures were modified by placing the tissues on floating polycarbonate filters on culture media, thereby allowing the easy manipulation of explants. In these cultures, 2A7-positive hair cells were differentiated from dividing precursor cells in vitro on the same schedule as in vivo. Furthermore, it was found that hair cells with both types of 2A7-IR were generated in culture as in vivo, indicating that a maturational process of hair cells also occurred. All these results as presented here suggest that the 2A7 monoclonal antibody as a hair cell-specific marker together with the culture system could be a potential tool in analysis of mechanisms underlying hair cell development.

Animals↗