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PubMed1978

Woolly hair nevus. Two case reports and a discussion of unruly hair forms.

Woolly hair is very curly hair that is characteristically unruly and will not form naturally into locks. Woolly hair nevus first appears when the scalp hair begins to grow. It is seen as a patch of unruly, very curly hair, arising in a field of otherwise unremarkable scalp hair. Woolly hair can also be seen as a hereditary trait involving the entire scalp and in acquired forms. It may be distinguished from two other types of unruly hair, pili torti and spun glass hair.

Adult↗
PubMed2004

cProx1 immunoreactivity distinguishes progenitor cells and predicts hair cell fate during avian hair cell regeneration.

In birds, mature sensory hair cells are regenerated continually in vestibular epithelia and after damage in the auditory basilar papilla. Molecular mechanisms governing the cellular processes associated with hair cell regeneration are poorly understood. Transcription factors are critical regulators of cell proliferation and differentiation in developing tissues. We examined immunoreactivity for cProx1 during both ongoing and damage-induced hair cell regeneration in chickens. Homologues of this divergent homeobox transcription factor are required for cell cycle withdrawal and differentiation in several vertebrate and invertebrate tissues. In the mitotically quiescent basilar papilla, a population of resting progenitor cells (supporting cells) shows faint nuclear immunoreactivity for cProx1. When auditory hair cell regeneration is triggered by experimental damage, nuclear cProx1 immunolabel is highly elevated in approximately 50% of dividing progenitor cells. Shortly after cytokinesis, all sibling pairs show symmetric patterns of nuclear cProx1 labeling, but pairs with asymmetric labeling emerge shortly thereafter. Strongly immunoreactive cells acquire the hair cell fate, whereas cells with low nuclear immunoreactivity differentiate as supporting cells. By contrast, cProx1 is not detected in any dividing progenitor cells during ongoing regeneration in the utricle. However, nuclear cProx1 immunoreactivity becomes asymmetric in postmitotic sibling cells, and as in the basilar papilla, cells with elevated cProx1 label differentiate as hair cells. In conclusion, cProx1 immunolabeling varies across sensory epithelial progenitors and distinguishes early differentiating hair cells from supporting cells. cProx1 may regulate the proliferative or differentiative capacities of progenitor cells and specify hair cell fate in postmitotic cells during avian hair cell regeneration.

Animals↗
PubMed1997

Influence of sample preparation on analytical results: drug analysis [GC/MS] on hair snippets versus hair powder using various extraction methods.

The comparison of aqueous extraction methods and hair extraction by organic solvents performed on hair powder as well as on hair snippets of the same sample revealed different qualities of the procedures. Qualitative and quantitative results by the same derivatization step and GC/MS detection demonstrated, that the risk of missing a drug substance is higher using hair snippets than after drug extraction on pulverised hair. Drug recovery for opiates, cocaine and benzoylecgonine from hair was found to be best in aqueous solvents or in methanol extracts. The results are discussed under the aspects of solid-phase extraction, the hair sample representing an inhomogenous material. The localisation of drug molecules in hair, the hair swelling and penetration behavior of the particular extraction medium as well as the partition coefficient of solvent/hair phase for a particular drug substance are considered to influence the results.

Gas Chromatography-Mass Spectrometry↗
PubMed1999

Differences in hair follicle dermal papilla volume are due to extracellular matrix volume and cell number: implications for the control of hair follicle size and androgen responses.

The size of a hair follicle is thought to be determined by the volume of its dermal papilla. The volume of the dermal papilla depends on the number of cells it contains and on the volume of the extracellular matrix. To establish which of these two variables is related to differences in hair follicle size we performed a stereologic study on 235 hair follicles from different sites, including male facial skin (beard), female facial skin, and scalp. In facial follicles there was a strong correlation between the area of the hair cortex and the volume of the dermal papilla. The area of the hair cortex also correlated with the number of cells in the dermal papilla and with the volume of dermal papilla per cell. In scalp hair follicles, where there was a smaller range of sizes, the correlations between these variables were weaker. In large male facial follicles the mean total dermal papilla volume was almost 40-fold higher than in vellus follicles from female facial skin. This difference was associated with a mean 17-fold greater number of cells in the dermal papilla and a 2.4-fold greater volume associated with each cell. Intermediate results were obtained in scalp follicles. In many regions of the skin hair follicles enlarge in response to androgens during adult life hair. Our results imply that the increase in the volume of the dermal papilla in these follicles is due to an increase in the number of cells, either through proliferation or through the migration of cells from the follicular dermal sheath, and to an increase in the amount of extracellular matrix per cell. As androgens are thought to act primarily on the dermal papilla, these changes may have a direct bearing on the mechanism of androgen-mediated alterations in hair follicle size.

Adolescent↗
PubMed1994

The Drosophila tissue polarity gene inturned functions prior to wing hair morphogenesis in the regulation of hair polarity and number.

The adult cuticular wing of Drosophila is covered with an array of distally pointing hairs. Mutations in the inturned (in) gene result in both abnormal hair polarity (i.e., hairs no longer point distally), and, in most cells forming more than one hair. We have isolated and characterized a collection of in alleles. Among this collection of alleles are a number of rearrangements that enable us to assign in to 77B3-5. Almost all of the in alleles, including putative null alleles, result in a stronger phenotype on the wing at 18 degrees than 29 degrees. The data argue that the in-dependent process is cold-sensitive. Temperature shift experiments with a hypomorphic allele show that this cold sensitivity can be relieved by several hours of incubation at the permissive temperature at a variety of times in the early pupae, but that this ability ends prior to the start of hair morphogenesis. One new allele showed a dramatic heat sensitivity. Temperature shift experiments with this allele revealed a very short temperature-sensitive period that is a few hours prior to the start of hair morphogenesis. That the temperature during hair morphogenesis is irrelevant for the phenotype of in is consistent with the hypothesis that the only role that in has in wing hair development is to regulate the initiation of hair morphogenesis.

Animals↗
PubMed1997

Hair analysis for drugs of abuse. XVII. Simultaneous detection of PCP, PCHP, and PCPdiol in human hair for confirmation of PCP use.

The paper reports the simultaneous detection hair of phencyclidine (PCP) and its two major metabolites, 1-(1-phenylcyclohexyl)-4-hydroxypiperidine (PCHP) and trans-1-(1-phenyl-4-hydroxycyclohexyl)-4'-hydroxypiperidine (t-PCPdiol) in human hair. The detection of these metabolites provides definitive evidence that a positive hair analysis result is due to active PCP use and not due to external contamination of the hair specimen. Hair (5 mg) from known PCP users was washed three times with 0.1% sodium dodecyl sulfate for 1 min before analysis. Three extraction methods were compared: methanol-5N HCl (20:1) (Method A), 10% HCl (Method B), and 2N sodium hydroxide digestion (Method C). PCP-d5 and PCHP-d5 were used as internal standards. Extracts were purified by Bond Elut Certify solid-phase extraction procedures. Samples were derivatized with N,O-bis-trimethylsilyl acetamide and analyzed by gas chromatography-mass spectrometry. Compared with Method A, the extraction efficiencies of Methods B and C for PCP were 83-89%; however, the extraction efficiencies of Methods B and C for the two metabolites were only half or less than that of Method A. Method A was therefore selected for the analysis of clinical hair specimens from eight PCP users. The coefficients of variation of this method (n = 5) for PCP at 4 ng/mg and for PCHP and t-PCPdiol at 0.2 ng/mg were 2.13, 6.09, and 9.38%, respectively. In the eight hair specimens, PCP values ranged between 0.33 and 14 ng/mg. PCHP between 0.02 and 0.12 ng/mg, and trans-PCPdiol between 0.09 and 0.45 ng/mg. It was found that t-PCPdiol was the major metabolite in the PCP users' hair specimens, although t-PCPdiol was a minor metabolite in the hair specimens of rats intoxicated with PCP.

Animals↗
PubMed1994

Hair follicle expression of 1,25-dihydroxyvitamin D3 receptors during the murine hair cycle.

Because the hair follicle is a highly hormone-sensitive miniorgan, the role of hormones produced locally in the skin in the control of hair growth deserves systematic analysis. It has been shown previously that the potent steroid hormone 1,25-dihydroxyvitamin D3 (1,25-D3) modulates growth and differentiation of keratinocytes via binding to a high-affinity nuclear vitamin D receptor (VDR). In this study, we have examined the in situ expression of VDR during the murine hair cycle. VDR expression was detected immunohistochemically. To obtain defined stages of the murine hair cycle, hair growth was induced by depilation in C57 BL-6 mice. In addition to the recognized VDR expression of outer root sheath keratinocytes, we detected VDR immunoreactive cells in the dermal papilla, the mesenchymal key structure of the hair follicle. Furthermore, VDR immunoreactivity in the nuclei of outer root sheath keratinocytes and in dermal papilla cells was stronger during anagen IV-VI and catagen than during telogen and anagen I-III. This suggests hair cycle-associated changes in the expression of VDR, and points to a potential role for 1,25-D3 in hair follicle biology. Selected follicular cell populations may display hair cycle-dependent sensitivity to 1,25-D3 stimulation.

Animals↗
PubMed2007

Oestrogen receptor antagonist and hair regrowth in dogs with hair cycle arrest (alopecia X).

An oestrogen receptor pathway that regulates the telogen-anagen hair follicle transition in mice has been described. The purpose of this study was to investigate whether fulvestrant, a pure oestrogen receptor antagonist, would cause hair regrowth in Pomeranian dogs with hair cycle arrest (alopecia X). Eleven Pomeranian dogs with hair cycle arrest were randomly assigned to receive two intramuscular injections of either 10 mg kg(-1) fulvestrant (n = 6) or an equal volume of saline (n = 5) 1 month apart. Complete blood count, chemistry panel, and urinalysis were monitored prior to the first injection and monthly for 2 months. Dogs were evaluated each month for degree of hair growth, percentage of body affected, and quality of new hair growth. Three control dogs received fulvestrant after the completion of the study. In addition, one control dog and one treatment dog received two subcutaneous injections of 20 mg kg(-1) fulvestrant 1 month apart. No dogs that received 10 mg kg(-1) fulvestrant had any evidence of hair regrowth. The control dog that received 20 mg kg(-1) fulvestrant had substantial hair regrowth 1 month after the first injection. No adverse effects from the treatment were noted. Fulvestrant does not appear to be a feasible treatment for dogs with hair cycle arrest (alopecia X) when administered intramuscularly at 10 mg kg(-1). A higher dose of fulvestrant requires more investigation but may be cost-prohibitive.

Alopecia↗
PubMed1998

Rapid Fire Hair Implanter Carousel. A new surgical instrument for the automation of hair transplantation.

BACKGROUND: As hair transplantation evolved into a procedure in which large numbers of very small grafts are moved in a single session, new problems have emerged. These include greater staffing requirements, longer operating time, additional technical difficulties, and increasing problems with quality control. OBJECTIVE: To introduce a new surgical instrument, the Rapid Fire Hair Implanter Carousel (Carousel), which can automate the most labor-intensive parts of the hair transplantation process, site creation and implant placement, by combining them into a single step and delivering them in rapid sequence. This instrumentation should help to minimize some of the human factors contributing to graft injury and to simplify and increase the speed of the hair transplant procedure. METHODS: In a patient with a Norwood IIIA balding pattern, 400 follicular implants were placed into a specific section of the bald scalp. The remainder of the bald scalp was transplanted with 800 follicular implants placed in the traditional way. The two areas were monitored and compared for intraoperative bleeding, ease of placing, total placing time, postoperative healing, and hair growth. Photographic documentation was obtained after surgery and at each postoperative visit. RESULTS: The Carousel visually produced less bleeding when compared with the manual approach. The Carousel was easier to use than the manual technique, since it eliminated graft insertion as a separate step. This was evidenced by the significantly shorter time required to insert the implants (40 grafts/minute with the Carousel vs 6.6 grafts/minute manually) and the decreased need for secondary manipulation once the grafts were inserted. Postoperative healing of the two groups were the same with regard to the duration of crusting and erythema. The rate of hair growth and the total amount of hair observed at 4 months were the same when identical size areas in test and control sides were compared. CONCLUSION: In this single patient pilot study, the Carousel greatly facilitated the placement of grafts by decreasing bleeding and obviating the extra step needed for the insertion of the implants. As a result, the total operative time decreased, shortening the time the grafts were outside the body, and decreasing the risk of desiccation and warming. By minimizing the human factor in this labor-intensive part of the procedure, the quality of the hair transplant should increase. It is anticipated that these benefits will result in increased hair yield. Further studies are needed, in a larger patient group, so that these benefits can be demonstrated.

Adult↗
PubMed1986

Immunological characteristics and histological distribution of human hair fibrous proteins studied with anti-hair keratin monoclonal antibodies HKN-2, HKN-4, and HKN-6.

By use of a mouse hybridoma technique, monoclonal antibodies were produced against hair fibrous proteins, which were extracted from normal human hairs. Three monoclonal antibodies, designated as HKN-2, HKN-4, and HKN-6, were chosen and used to investigate the immunological characteristics of hair fibrous proteins. Epidermal fibrous proteins were also extracted from human sole callus horny materials. Hair or epidermal fibrous proteins were electrophoretically separated on polyacrylamide gels with sodium dodecyl sulfate. By immunoblot analyses, HKN-2 and HKN-4 marked the electrophoretic bands of both proteins; however, HKN-6 reacted only with the bands of hair fibrous proteins. Immunohistochemically, all three monoclonal antibodies stained the keratogenous zone of anagen hairs. HKN-6 did not react with any other skin components or with tissues of other organs examined. Although HKN-2 showed reactions with skin epithelial tissues, except for epidermal basal cells and secretory cells of sweat glands, the reactivity of HKN-2 was limited within the skin. HKN-4 displayed a broad crossreactivity with all of the skin epithelial cells and various epithelial cells of other organs. These findings indicate that some components of hair fibrous proteins are immunologically specific to hair cells, whereas others broadly crossreacted with the fibrous proteins of other skin epithelial cells or with those of various epithelial cells. The anti-hair keratin monoclonal antibodies seem useful to examine the differentiation patterns of epithelial cells and tissues.

Antibodies, Monoclonal↗
PubMed2001

Hair analysis for pharmaceutical drugs. II. Effective extraction and determination of sildenafil (Viagra) and its N-desmethyl metabolite in rat and human hair by GC-MS.

In order to study the incorporation of sildenafil (SDF) and its N-demethylated metabolite (norSDF) into hair, animal model experiments were carried out. After shaving the back hair, SDF was dosed to two sets of three male dark-agouti pigmented rats (5 weeks old) per each group at 25 mg/kg once a day for 5 successive days with intraperitoneal (i.p.) (set1) and oral administration (set2). The regrown back hair was collected 14 d after the first administration. Three typical extraction methods, using methanol-5 M hydrochloric acid, methanol-trifluoroacetic acid and 1 M sodium hydroxide, were evaluated using the rat hair samples containing SDF and norSDF. Methanol-5 M hydrochloric acid was the best extraction method in terms of high efficiency and reproducibility. The extract was purified using Bond Elut Certify columns and was derivatized with trimethylsilylimidazole: N,O-bis(trimethylsilyltrifluoroacetamide): trimethylchlorosilane (3: 3: 2) at 90 degrees C for 30 min. The trimethylsilylated products were analyzed by GC-MS using selected ion monitoring. SDF and norSDF were simultaneously detected in the rat hair. The hair concentrations were 4.9-6.3 (av. 5.8) ng/mg and 15.6-20.3 (av. 17.6) ng/mg for SDF and norSDF, respectively, with i.p. administration, and 2.6-4.1 (av. 3.6) ng/mg and 8.1-10.4 (av. 9.1) ng/mg with oral administration. The hair concentrations of norSDF were about three times higher than those of SDF, and the ratios of both compounds showed no significant difference between i.p. and oral administrations. This method was applied to the scalp hair of two patients who orally took SDF at regular intervals for the treatment of penile erectile dysfunction. The hair concentrations of SDF and norSDF in the two patients were 19.8 and 55.9 ng/mg, and 1.7 and 5.6 ng/mg, respectively.

Administration, Oral↗
PubMed1994

Drug-induced hair loss and hair growth. Incidence, management and avoidance.

A large number of drugs may interfere with the hair cycle and produce hair loss. Drugs may affect anagen follicles through 2 main different modalities: (i) by inducing an abrupt cessation of mitotic activity in rapidly dividing hair matrix cells (anagen effluvium) or (ii) by precipitating the follicles into premature rest (telogen effluvium). In anagen effluvium, hair loss usually occurs within days to weeks of drug administration, whereas in telogen effluvium, hair loss becomes evident 2 to 4 months after starting treatment. Anagen effluvium is a prominent adverse effect of antineoplastic agents, which cause acute damage of rapidly dividing hair matrix cells. Telogen effluvium may be a consequence of a large number of drugs including anticoagulants, retinol (vitamin A) and its derivatives, interferons and antihyperlipidaemic drugs. Drug-induced hair loss is usually reversible after interruption of treatment. The prevalence and severity of alopecia depend on the drug as well as on individual predisposition. Some drugs produce hair loss in most patients receiving appropriate dosages while other drugs are only occasionally responsible for hair abnormalities. Both hirsutism and hypertrichosis may be associated with drug administration. Drugs most commonly responsible for the development of hirsutism include testosterone, danazol, corticotrophin (ACTH), metyrapone, anabolic steroids and glucocorticoids. Hypertrichosis is a common adverse effect of cyclosporin, minoxidil and diazoxide.

Alopecia↗
PubMed2000

Correction of the cornrow hair transplant and other common problems in surgical hair restoration.

Hair on a man's head is an important emblem of health, youth, and vitality. As in all areas of cosmetic surgery, the refinements of surgical technique and instrumentation have improved the results of hair transplantation. The state of the art in hair grafting today produces a result that is undetectable as being a surgical hair transplant. Many earlier techniques of plug hair transplantation are not aesthetically acceptable by today's standards. This is especially true in the face of progressive hair loss, which can unmask previously camouflaged cornrow plugs. A technique to reduce the plugs and recycle the grafts into smaller grafts is described. The recycled hair grafts can be combined with scalp lifting, scalp reductions, and occipital harvesting of grafts to improve the results of cornrow appearing hair transplants and other problems of surgical hair restoration.

Adult↗
PubMed2002

Mechanisms of active hair bundle motion in auditory hair cells.

Sound stimuli vibrate the hair bundles on auditory hair cells, but the resulting motion attributable to the mechanical stimulus may be modified by forces intrinsic to the bundle, which drive it actively. One category of active hair bundle motion has properties similar to fast adaptation of the mechanotransducer channels and is explicable if gating of the channels contributes significantly to the mechanics of the hair bundle. To explore this mechanism, we measured hair bundle compliance in turtle auditory hair cells under different conditions that alter the activation range of the channel. Force-displacement relationships were nonlinear, possessing a maximum slope compliance when approximately one-half of the transducer channels were open. When the external calcium concentration was reduced from 2.8 to 0.25 mm, the position of maximum compliance was shifted negative, reflecting a comparable shift in the transducer channel activation curve. Assuming that the nonlinearity represents the compliance attributable to channel gating, a single-channel gating force of 0.25 pN was calculated. By comparing bundle displacements with depolarization with and without an attached flexible fiber, the force contributed by each channel was independently estimated as 0.47 pN. These results are consistent with fast active bundle movements resulting from changes in mechanotransducer channel gating. However, several observations revealed additional components of hair bundle motion, with slower kinetics and opposite polarity to the fast movement but also linked to transducer adaptation. This finding argues for multiple mechanisms for controlling hair bundle position in auditory hair cells.

Animals↗
PubMedDate not supplied

Analyzing the laser-light reflection from human hair fibers. II. Deriving a measure of hair luster.

Hair shine or luster is perceived as an important, though analytically somewhat elusive, attribute of beauty, primarily associated with clean and healthy hair. Principles for the assessment of hair luster are developed that are consistent with the practical situation. These principles are related to the components of light, specularly and diffusely reflected from single hair fibers, as measured by laser-based, multiangle goniophotometry, presented in Part I. Considering various definitions of gloss, their tradition, practical implementation, and their inherent limitations for testing hair, the gloss index as a physically consistent measure of hair luster is derived from the ratio of the integral intensities of the light components. Changes of the parameter values along hair length, namely their decrease, are analyzed for hairs of different color and ethnic origin. The correlation with shine evaluations of hair tresses by panels, based on literature data, is analyzed and ascertained.

Hair↗
PubMed1985

Structural changes of hair after incorporation of the proline analogue L-azetidine-2-carboxylic acid. A model of hair disease by alteration of primary structure.

In order to correlate biochemical changes of the hair with physical properties we present a model for the examination techniques. L-azetidine was incorporated into the hair keratin complex and the resulting mechanoelastic properties were determined using the ultramicrohardness testing system on scanning electron microscopy. Structure was investigated by X-ray diffraction and incorporation of L-azetidine was detected by thin-layer chromatography. This system could possibly be introduced for examination of hair changes in humans. 8 white mice, 3 weeks of age, were given L-azetidine-2-carboxylic acid in water (0.1 g/100 ml) as only source of fluid over a period of 5 weeks. They had free access to dry mouse cake only. 8 animals of the same strain, who had free access to tap water and mouse cake and were kept under the same conditions, served as controls. After 5 weeks, the animals were sacrificed and hair was obtained for analyses. 2 dimensional thin-layer chromatography of hair hydrolyzed with 6N HCl at 105 degrees C for 12 hours revealed 2 additional spots in the chromatographic pattern in the experimental animals in comparison with the control group. 1 of the spots was identified as L-azetidine-2-carboxylic acid, while the second spot was possibly a degradation product of L-azetidine on acid hydrolysis at a high temperature. Hair of the animals was put into Mark capillaries and subjected to X-ray diffraction, which showed a markedly disordered orientation of keratin. Impression studies using scanning electron microscopy revealed a remarkably reduced elasticity of hair with incorporated L-azetidine. These findings may be explained on the basis of qualitative or quantitative changes in the helical structure of the keratin complex of hair, which is responsible for the elastic properties, whereas the globular matrix is responsible for the firmness of the hair.

Animals↗
PubMed1980

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

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.

Adolescent↗
PubMed1995

[Age estimation by appearance of gray hair in pubic hair].

The pubic hair of Japanese males aged 12-90 years old (n = 123) and females 14-85 ys. (n = 80) autopsied during 1984-1993 was investigated to determine its appearance age and possible appearance age of gray hair. As the appearance degree of gray hair in pubic hair 5 stages were applied to samples to establish a criterion for age estimation. Stage 0; no gray hair, 1; 1-3 gray hairs, 2; a few-10, 3; 10 gray hairs-2/3 of the entire pubic hair, 4; more than 3/4. The appearance age of gray hair with appearance rate 100% (75%) was more than 65 (55) ys. in both sex. The possible appearance age was more than 30 ys. in males and 36 ys. in females, practically younger than "45 years old" which had been described in texts. The age range with a hit rate 100% is at stage 0; less than 62 ys. in males, less than 59 ys. in females, at stage 1; 30-64 ys. in males, 36-60 ys. in females, at stage 2; 43-72 ys., 39-85 ys. and at stage 3; 49-77 ys,--.

Adolescent↗