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PubMedDate not supplied

Influence of depigmenting chemical agents on hair and skin color in yellow (pheomelanic) and black (eumelanic) mice.

Topical applications of monobenzylether of hydroquinone (MBEH) or intraperitoneal injections of phenol induced graying of hair in eumelanic mice but had little effect on hair color in pheomelanic mice. Amcinonide, an anti-inflammatory agent, elicited whitening of a few hairs in both pheomelanic and eumelanic mice. In phenol-treated eumelanic mice, damaged follicular melanocytes were uprooted from hair bulbs and incorporated into the developing hair. The fate of follicular melanocytes in MBEH- or amcinonide-treated mice was not determined since hair growth and graying were more variable than in phenol-treated mice. In contrast to the susceptibility of eumelanic hair follicles to depigmentation by phenol or MBEH, the tail skin of eumelanic or pheomelanic mice was not depigmented by these agents. Overall, during the 3 week period of treatment that was sufficient for phenol or MBEH to elicit graying of hair, epidermal melanocytes of the tails of eumelanic or pheomelanic mice either failed to respond (phenol) or were stimulated in their "proliferative" and melanogenic activity (MBEH). In contrast, amcinonide brought about a marked reduction in the numbers of DOPA-positive epidermal melanocytes inhabiting the tails of eumelanic or pheomelanic mice. Amcinonide exerted a deleterious influence on the structure and function of tail epidermis. Its actions were partly reversed by simultaneous treatment with MBEH but not with prostaglandin (PGE2).

Administration, Topical↗
PubMed1995

Sun protection and sunscreen use after surgical treatment of basal cell carcinoma.

Sixty-three patients (mean age 54 +/- 9 years) who were treated for a basal cell carcinoma (BCC) and 54 control subjects (mean age 51 +/- 11 years) filled out detailed questionnaires on their sun exposure and sun protection habits. Patients were given the questionnaires at least 1 year after their skin tumors had been excised. Differences between patients and controls in mean age, gender, Fitzpatrick's skin type and eye and hair color were statistically nonsignificant. The level of education was high in both patients and controls (mean of 13.4 +/- 3.1 school years). Differences in education were statistically nonsignificant. We found that both patients and controls were knowledgeable about the role of sunscreens in preventing skin tumors (79% and 83% respectively) and in preventing sun-induced aging (90% and 85% respectively). Significantly more patients used sunscreens regularly (64%) compared with controls (36%). Nevertheless, our data show no statistically significant differences between the sun exposure habits of the patients previously treated for BCC and controls. Moreover, we found that, although 82% of the patients declared that they tried to avoid sun, only 49% regularly wore hats or shirts with long sleeves in the summer (19%). Sixty-two percent of the patients used two or fewer bottles of sunscreens per year, which is inadequate for effective year-round sun protection. In addition, we found that many patients, as well as the controls, applied sunscreens only once a day (57% and 46% respectively), did not reapply after swimming (58%, 74% respectively), and did not use sunscreens in the winter (49%, 61%). Our data show that, although patients after BCC removal have a significantly higher sunscreen use compared with controls, the amount and methods of application are less than adequate. Moreover, other simpler methods to prevent photodamage, such as simple sun avoidance or the use of protective clothing, are often neglected.

Attitude to Health↗
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↗
PubMed1997

Identification of common polymorphisms in the coding sequence of the human MSH receptor (MCIR) with possible biological effects.

The extension locus has been identified in many mammalian species as a gene that determines the relative amounts of eumelanin and phaeomelanin pigments in hair and skin. In at least three species, this locus has been demonstrated to encode the melanocyte-stimulating hormone receptor (MC1-R), and functionally variant alleles have been demonstrated to cause a broad range of pigmentation phenotypes. To test for MC1-R allelic variation in man, genomic DNA was extracted from skin samples collected from patients with different skin types (I-VI), and eye and hair color. A PCR-based approach was used to amplify the full-length coding sequence of the MC1-R and the resulting products were sequenced. Two polymorphic alleles were identified with single point mutations in the coding sequence: a valine-to-methionine substitution at position 92 (V92M), and an aspartic acid-to-glutamic acid substitution at position 84 (D84E). RFLP analysis demonstrated the presence of the V92M allele in 4 out of 60 (6.6%) of individuals examined, predominantly those with blue eyes and blond hair. This polymorphism was found in both heterozygous and homozygous states in individuals with type I skin. The D84E allele was found in one individual with skin type I; this person also has the V92 M allele and thus is a compound heterozygote.

Amino Acid Sequence↗
PubMed1982

Mineral concentrations in hair as indicators of mineral status: a review.

Mineral content of hair is affected by season, breed, hair color within and between breeds, sire, age and body location. Seasonal effects may be due to stage of growth of hair and to changes caused by perspiration, surface contamination and diet. Breed and sire effects on mineral content of hair complicate prediction of nutritional status based on hair analyses because, in many commercial cattle, neither breed nor sire is known. Hair from young animals may be lower in Zn, Mn and Fe, but is higher in Na, Ca, Cu and K than that from older animals. Pigmented hair apparently is higher in Ca, Mg, K and NA than white hair, but trace mineral concentrations are similar in hair of different colors. The effect of body location on mineral content of hair may be due to differences in surface contamination, differences in hair growth cycles and differences in texture of the hair. Concentrations of Ca, P and Cu in hair are not affected by dietary intake of these minerals. Zn and Se contents of hair may reflect dietary intake. Information on other required minerals in lacking. Pb, As and, possibly, Cd levels in hair may be related to dietary or environmental exposure. Because of the many factors that cause variation in mineral content of hair, hair analyses are not likely to be precise indicators of the mineral status of animals. Hair analyses may help to detect severe deficiencies of some required minerals or exposure to some heavy metals. However, if hair analyses are to be conducted, care must be taken to compare values from test animals with those from animals of similar breed, sex, season, sire and color. In addition, new hair growth should be analyzed, environmental contamination should be minimized and the hair samples should be cleaned before analyses.

Age Factors↗
PubMed1998

Human pigmentation genetics: the difference is only skin deep.

There is no doubt that visual impressions of body form and color are important in the interactions within and between human communities. Remarkably, it is the levels of just one chemically inert and stable visual pigment known as melanin that is responsible for producing all shades of humankind. Major human genes involved in its formation have been identified largely using a comparative genomics approach and through the molecular analysis of the pigmentary process that occurs within the melanocyte. Three classes of genes have been examined for their contribution to normal human color variation through the production of hypopigmented phenotypes or by genetic association with skin type and hair color. The MSH cell surface receptor and the melanosomal P-protein are the two most obvious candidate genes influencing variation in pigmentation phenotype, and may do so by regulating the levels and activities of the melanogenic enzymes tyrosinase, TRP-1 and TRP-2.

Albinism↗
PubMed2006

[Study on appraisement and determination GHB levels in hair].

OBJECTIVE: The possibility for the identification of GHB administration through hair analysis was investigated to provide method and information for toxicology examination of GHB. METHODS A GC/MS assay for GHB in hair was developed. Endogenous levels of GHB in hair, time course of GHB in hair, relationship between GHB levels in hair and hair color or administration dose were also established by guinea pig model. RESULTS: Endogenous levels of GHB in guinea pig black hair and human black hair were (3.01 +/- 1.41) ng/mg (n=28) and (1.02 +/- 0.27) ng/mg (n=20), respectively. GHB levels in black hair were increased by GHB administration and related with drug dosage, and also much higher than in brown and white hair. CONCLUSION: Analysis of GHB in hair is suitable for investigation of GHB abuse in forensic toxicology and GHB level in segmental analysis compared with endogenous level of GHB may provide useful information about GHB administration.

Animals↗
PubMedDate not supplied

Ultraviolet damage on natural gray hair and its photoprotection.

The physicochemical properties of natural gray hair obtained from the heads of individuals and as well as commercial samples were investigated. No statistically significant differences were observed in terms of their central maximum diameter, central cross-sectional area, central ellipticity, average tensile strength, and average extent of transverse swelling between gray and black hair. The correlation between the elongation and the contraction of the cross-sectional area of hair fibers during extension was established as a statistically linear function, with a coefficient of 0.758. The damage on natural gray hair from ultraviolet (UV) irradiation were assessed by measuring the following parameters: hair color, Young's modulus, stress-to-break, wet combing force, dynamic advancing contact angle, tryptophan damage, cuticle abrasion, and transverse swelling of hair fiber in 0.1 N NaOH solution. It has been found that gray hair undergoes more severe UV damage and needs more UV protection than dark brown hair. Experimental results indicate that the quaternized UV absorber, cinnamidopropyltrimonium chloride (CATC), delivered from a simple shampoo system, is more substantive on hair and more effective in protecting hair from UV damage than a conventional UV filter. CATC also provided an additional conditioning benefit on hair.

Hair↗
PubMed2001

Hair reduction using a scanning 800 nm diode laser.

BACKGROUND: Numerous lasers are currently available for hair removal, yet there are still few studies that have examined the role of fluence, light dose, hair color, and treatment number in laser hair reduction. OBJECTIVE: To demonstrate the efficacy and safety of a scanning 800 nm diode laser for hair reduction. METHODS: An 800 nm scanning diode laser was used to deliver 24, 38, or 48 J/cm2 to a 3 cm x 3 cm area of skin located on the back, groin/bikini area, or thigh in 36 adult patients with varying shades of brown or black hair. Patients received one to four treatments during the course of the study. Hair loss was evaluated at both 30 and 90 days after final treatment. Biopsies were obtained from 20 consenting patients. RESULTS: Significant fluence-dependent hair reduction was demonstrated between treatment and control groups. At 48 J/cm2, the highest dose, a mean hair reduction of 43% was achieved 30 days after the final treatment, and 34% was achieved 90 days after the final treatment. Darker hairs were more effectively treated than lighter hairs. CONCLUSIONS: Hair reduction can be safely and effectively achieved using a scanning 800 nm diode laser.

Adult↗
PubMed2003

Cocaine, benzoylecgonine, amphetamine, and N-acetylamphetamine binding to melanin subtypes.

Experiments have been performed to document the in vitro binding of cocaine, benzoylecgonine (BE), amphetamine, and N-acetylamphetamine (N-AcAp) to synthetic melanin subtypes. The two predominant melanin types in hair are the black eumelanins and the reddish-brown pheomelanins. The melanins included in this study are two black eumelanin subtypes [5,6-dihydroxyindole (DHI) and 5,6-dihydroxyindole-2-carboxylic acid (DHICA) derived melanins], a reddish-brown pheomelanin [from 5-cysteinyl-S-Dopa (5-CysDOPA)], and two mixed eu-/pheomelanin copolymers. Results indicate that the basic drugs cocaine and amphetamine bind to eumelanins and mixed eu-/pheomelanins to varying degrees, but not to pure pheomelanin. BE and N-AcAp, net neutral molecules, do not bind to any type of melanin. As a model of which eumelanin chemical functional groups bind drugs, amphetamine was shown, using tandem mass spectrometry, to form a noncovalent adduct with dimerized oxidized catechol. Similar functional groups on the eumelanin polymer may represent an important drug-binding site. Overall, these findings show that basic drugs have a greater affinity for melanin than their net neutral analogues, reveal that melanin types differ when it comes to drug binding, help elucidate what properties of melanin are important for drug binding, and help explain why hair color biases exist.

Amphetamine↗
PubMed1994

Targeted disruption of Bcl-2 alpha beta in mice: occurrence of gray hair, polycystic kidney disease, and lymphocytopenia.

Mice carrying ablated coding regions of the bcl-2 alpha and bcl-2 beta transcripts have been made. bcl-2-/- mutants are smaller but viable, although about half of them die by 6 weeks of age. As shown earlier with somatic bcl-2 gene-targeted mice, the number of lymphocytes markedly decreased within few weeks after birth while other hematopoietic lineages remained unaffected. Among lymphocytes, CD8+ T cells disappeared most quickly followed by CD4+ T cells, whereas B cells were least affected. bcl-2-/- lymphocytes, however, could respond normally to various stimuli including anti-CD3, Con A, phorbol 12-myristate 13-acetate plus ionomycin, interleukin 2, lipopolysaccharide, and anti-IgM antibody. Abnormalities among nonlymphoid organs include smaller auricles, hair color turning gray at 4-5 weeks of age, and polycystic kidney disease-like change of renal tubules. These results suggest that Bcl-2 may be involved during morphogenesis where inductive interactions between epithelium and mesenchyme are important such as in the kidneys, hair follicles, and perichondrium of auricles. Surprisingly, the nervous system, intestines, and skin appear normal despite the fact that these organs show high levels of endogenous Bcl-2 expression in normal mice.

Animals↗
PubMed1999

A case-control study of malignant melanoma in Israeli kibbutzim.

BACKGROUND: Incidence rates for malignant melanoma in Israel are rising steadily, and the kibbutz population is at increased risk for this malignancy. OBJECTIVES: To assess the risk factors for malignant melanoma among kibbutz members compared to matched healthy controls. METHODS: We conducted a case-control study of 168 malignant melanoma patients and 325 healthy controls, matched by age and gender. Data were collected on three categories of risk: demographic, personal (e.g., skin, eye and hair color), and environmental/behavioral (e.g., sun exposure, use of sunscreens). RESULTS: There were no differences between the groups regarding sociodemographic data. Significantly more patients than controls had fair, vulnerable skin (P < 0.001), light eyes (P < 0.05), and fair hair (P < 0.001). There was no difference in family history of malignant melanoma or other cancers. Patients with malignant melanoma had significantly more additional skin lesions (e.g., keratoses) (P < 0.001). More patients than controls recalled having been exposed to the sun for long periods when they were 6-13 years of age. A conditional logistic regression analysis showed that fair hair, fair vulnerable skin, and additional skin lesions were independently associated with malignant melanoma (P < 0.01). CONCLUSIONS: The main target population for interventions to reduce the incidence of malignant melanoma among kibbutz members should be individuals with these risk factors. A history of increased exposure to the sun from age 6 to 13 should also be taken into account as an independent risk factor.

Adult↗
PubMed2004

Assessment of polymorphic variants in the melanocortin-1 receptor gene with cutaneous pigmentation using an evolutionary approach.

The melanocortin-1 receptor gene (MC1R) encodes a membrane-bound receptor protein that is central to melanin synthesis. The coding region of MC1R is highly polymorphic and associations of variants with pigmentation phenotypes and risk for cutaneous neoplasms have been reported. We sought to determine the distribution and frequency of MC1R variants and their relationship to pigmentation characteristics in 179 Caucasian controls from the United States. One hundred thirty-five (75.4%) subjects carried one or more variants, and we determined that carriage of the previously designated "red hair color" (RHC) alleles, R151C, R160W, and D294H was strongly associated with fair pigmentation phenotypes including light hair and eye color, tendency to burn, decreased tendency to tan, and freckling. We used SIFT software to define MC1R protein positions that were predicted intolerant to amino acid substitutions; detected variants that corresponded to intolerant substitutions were D84E, R142H, R151C, I155T, R160W, and D294H. Carriage of one or more of these putative functionally important variants or the frameshift variant ins86A was significantly associated with fair pigmentation phenotypes. Analyses limited to carriage of ins86A and the three non-RHC alleles identified by SIFT were attenuated and no longer reached statistical significance. This is the first study to describe MC1R variants among control subjects from the U.S. Our results indicate that the frequency of variants is similar to that previously observed among non-U.S. Caucasians. Risk variants defined by either the published literature or by evolutionary criteria are strongly and significantly associated with all fair pigmentation phenotypes that were measured.

Adult↗
PubMed1989

[Pili anulati].

Report on a 10 year-old girl with pili anulati. Clinical and microscopical findings of that maldevelopment of hair are described. Interestingly, an episodical alopecia totalis and subsequent regrow exhibiting different hair color was observable. Genealogical search confirmed autosomal dominant genetics. The question of expressivity of that dominant gen is discussed.

Alopecia↗
PubMed2006

Women with red hair report a slightly increased rate of bruising but have normal coagulation tests.

There is an anecdotal impression that redheads experience more perioperative bleeding complications than do people with other hair colors. We, therefore, tested the hypothesis that perceived problems with hemostasis could be detected with commonly used coagulation tests. We studied healthy female Caucasian volunteers, 18 to 40 yr of age, comparable in terms of height, weight, and age, with natural bright red (n = 25) or black or dark brown (n = 26) hair. Volunteers were questioned about their bleeding history and the following tests were performed: complete blood count, prothrombin time/international normalized ratio, activated partial thromboplastin time, platelet function analysis, and platelet aggregation using standard turbidimetric methodology. Agonists for aggregation were adenosine diphosphate, arachidonic acid, collagen, epinephrine, and two concentrations of ristocetin. The red-haired volunteers reported significantly more bruising, but there were no significant differences between the red-haired and dark-haired groups in hemoglobin concentration, platelet numbers, prothrombin time/international normalized ratio, or activated partial thromboplastin time. Furthermore, no significant differences in platelet function, as measured by platelet function analysis or platelet aggregometry, were observed. We conclude that if redheads have hemostasis abnormalities, they are subtle.

Adult↗
PubMed1987

Determination of lead in hair of exposed gas station workers and in unexposed adults by microwave-aided dissolution of samples and flow injection/atomic absorption spectrometry.

Lead content in head hair of 53 gas station workers together with an equal number of normal controls was determined. Samples of hair were washed with ethanol and water and microwave-aided wet digested prior to the determination of lead by flow injection/atomic absorption spectrometry. The lead content in hair of the gas station workers (48.7 +/- 17.5 micrograms/g) was significantly higher than that of the normal controls (17.2 +/- 8.1 micrograms/g). The effects of washing and sample digestion procedures, head sampling site, hair color, age, smoking habits and duration of exposure to the metal are discussed.

Adolescent↗
PubMed2000

Is there a place for hair analysis in doping controls?

The actual antidoping control rules applied in sports (as established by the International Olympic Committee and the International Sport Federations) state that a positive case is chemically established by the unequivocal detection of a forbidden parent molecule and/or any of its metabolite(s) in urine, no matter the amounts which were administered and when the drug was taken. Screening is accomplished most of the time by using GC-MS procedures. These have been optimized to detect most if not all of the forbidden compounds which are put on a list. Recently, attempts have been made on scalp hair to demonstrate the value of this matrix as a possible means for differentiating between therapeutic use and doping abuse. In particular, GC-mass selective detector and GC-high resolution MS were successfully applied to treated animals and body-builders for anabolic agents (steroids and beta-2-agonists) at high sensitivity detection (low ng/g level). Naturally occurring molecules, like testosterone and its metabolites, could also be differentiated from their synthetic counterparts. Positive cases are more often challenged in courts and retrospectivity in time of the drug(s) intake is becoming an important issue for evaluating the responsibility of the person. This is can be based on hair analyses if the drugs have been taken at regular intervals. Stimulants and narcotics are often used in sports like drug of abuse in the ordinary social contexts. On the other hand, anabolic agents, when taken to improve the physical performances, follow complex regimens with the mixing of various formulas and dosages. Scalp hair references ranges for these as well as for endogenous substances still wait to be established statistically for competing, well-trained athletes. The incorporation rate into blond or gray hair is poorer than that of dark colored hair raising the question of individuals equality against the controls, a very important matter of concern for the sport's governing bodies. The frequency of hair cutting and short hair cuts necessary to gain speed in specific sports like swimming are other critical factors. On the other hands, irregular hair growth, associated with the washout effect through multiple washing and staining processes over expanded time intervals can cause concentrating or diluting effects. So far, a minority of prohibited substances could be detected in scalp hair with the sensitivity and specificity required in the context of the sport's activities. From the above, clear limitations of the usefulness of hair analysis in doping control analysis are obvious until a lot more data relevant to this particular field have been collected.

Doping in Sports↗