Normal hair anatomy and architecture

AbstractSince 2013, a high incidence of bilateral symmetrical alopecia has been observed in free-ranging Formosan macaques (Macaca cyclopis) in Mt. Longevity, Taiwan. We hypothesized that stress induces alopecia in this population. To verify our hypothesis, we evaluated the histopathological characteristics of skin biopsy and used a validated enzyme immunoassay (EIA) for fecal glucocorticoid metabolite (FGM) analysis, which act as an indicator of stress experienced by the individual. Follicular densities were lower (2.1–3.0 mm2) in individuals with symmetrical alopecia than in those with normal hair conditions (4.7 mm2). Furthermore, anagen to catagen/telogen ratios were lower in individuals with alopecia (0–1.4) than in those with normal hair (4.0). The histopathological characteristics of alopecia were similar to those of telogen effluvium, which indicates that stress is one of the possible etiologies. On the basis of the analytical and biological validation of EIAs for FGM analysis, 11β-hydroxyetiocholanolone was considered suitable for monitoring adrenocortical activity in both sexes of Formosan macaques. The mean concentrations (standard error; sample size) of 11β-hydroxyetiocholanolone were 2.02 (0.17; n = 10) and 1.41 (0.10; n = 31) μg/g for individuals with and without alopecia, respectively. Furthermore, the results of logistic regression analysis show that 11β-hydroxyetiocholanolone (p = 0.012) concentration was positively associated with alopecia. Thus, stress was the most likely to trigger symmetrical alopecia in Formosan macaques in Mt. Longevity. Although stress can decrease the fitness of an individual, considering the population status of Formosan macaques in Taiwan is stable and alopecia was only observed in our study area, which is isolated from other populations, the impact on the total population of Formosan macaque in Taiwan is limited. Nonetheless, stress-induced immunosuppression and alopecia might affect the local abundance and increase zoonosis risk due to frequent human–macaque contact in Mt. Longevity. Future studies are suggested to focus on the causative factor of stress and the effects of stress and alopecia on the health and welfare in the Formosan macaques.

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Quantitative and physical characterization of normal hair ageing in White European women: a single‐centre study

Journal of the European Academy of Dermatology and Venereology ◽

10.1111/jdv.17246 ◽

2021 ◽

Vol 35 (S2) ◽

pp. 21-23

Author(s):

V. Turlier ◽

V. Mengeaud ◽

C. Lauze ◽

J. Kottner ◽

U. Blume-Peytavi

Keyword(s):

Physical Characterization ◽

Single Centre ◽

Centre Study ◽

Normal Hair ◽

Single Centre Study ◽

European Women

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Association Between Stress and Bilateral Symmetrical Alopecia in Free-Ranging Formosan Macaques (Macaca Cyclopis) in A High-Population-Density Area

10.21203/rs.3.rs-294025/v1 ◽

2021 ◽

Author(s):

Chen-Chih Chen ◽

Ai-Mei Chang ◽

Ming-Shan Tsai ◽

Yen-Hua Huang ◽

Kurtis Jai-Chyi Pei ◽

...

Keyword(s):

Total Population ◽

High Population Density ◽

Macaca Cyclopis ◽

Adrenocortical Activity ◽

Biological Validation ◽

High Incidence ◽

Normal Hair ◽

The Mean ◽

The Individual ◽

Free Ranging

Abstract Since 2013, a high incidence of bilateral symmetrical alopecia has been observed in free-ranging Formosan macaques (Macaca cyclopis) in Mt. Longevity, Taiwan. We hypothesized that stress induces alopecia in this population. To verify our hypothesis, we evaluated the histopathological characteristics of skin biopsy and used a validated enzyme immunoassay (EIA) for fecal glucocorticoid metabolite (FGM) analysis, which act as an indicator of stress experienced by the individual. Follicular densities were lower (2.1–3.0 mm2) in individuals with symmetrical alopecia than in those with normal hair conditions (4.7 mm2). Furthermore, anagen to catagen/telogen ratios were lower in individuals with alopecia (0–1.4) than in those with normal hair (4.0). The histopathological characteristics of alopecia were similar to those of telogen effluvium, which indicates that stress is one of the possible etiologies. On the basis of the analytical and biological validation of EIAs for FGM analysis, 11β-hydroxyetiocholanolone was considered suitable for monitoring adrenocortical activity in both sexes of Formosan macaques. The mean concentrations (standard error; sample size) of 11β-hydroxyetiocholanolone were 2.02 (0.17; n = 10) and 1.41 (0.10; n = 31) μg/g for individuals with and without alopecia, respectively. Furthermore, the results of logistic regression analysis show that 11β-hydroxyetiocholanolone (p = 0.012) concentration was positively associated with alopecia. Thus, stress was the most likely to trigger symmetrical alopecia in Formosan macaques in Mt. Longevity. Although stress can decrease the fitness of an individual, it should not impact the total population of Formosan macaque in Taiwan. Nonetheless, stress-induced immunosuppression might increase zoonosis risk due to frequent human–macaque contact in Mt. Longevity.

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Variation of Hair Follicle Counts among Different Scalp Areas: A Quantitative Histopathological Study

Skin Appendage Disorders ◽

10.1159/000518434 ◽

2021 ◽

pp. 1-7 ◽

Cited By ~ 1

Author(s):

Suthinee Rutnin ◽

Kumutnart Chanprapaph ◽

Kallapan Pakornphadungsit ◽

Kanchana Leerunyakul ◽

Yingluck Visessiri ◽

...

Keyword(s):

Gender Differences ◽

Reference Values ◽

Definitive Diagnosis ◽

Histopathological Study ◽

Hair Cycle ◽

Biopsy Specimens ◽

Histopathological Evaluation ◽

Normal Hair ◽

Scalp Biopsy ◽

Vellus Hairs

Introduction: Scalp biopsy is a standard method for the definitive diagnosis of alopecia. The hair count parameters of each scalp area remain unclear. This study aimed to determine hair count values at different scalp locations from histopathology and to establish reference values for each part of the scalp. Methods: We obtained biopsy specimens from the frontal, vertex, temporoparietal, and occipital areas of the scalps of normal deceased subjects. All specimens were evaluated for the number of follicular units, hair counts, hair types, and stages of the hair cycle. Results: In total, 240 specimens were collected from 60 cadavers. Across all scalp sites, the temporoparietal area showed the lowest mean hair count, number of follicular units, terminal and vellus hairs, and terminal-to-vellus hair ratio. The average anagen-to-telogen hair ratio was comparable across all scalp sites. This study did not observe a significant association of hair parameters with gender differences or increasing age in all scalp areas. Conclusions: The present study revealed the diversity of the hair index among different scalp areas and suggested that normal hair count values should be separately standardized on each scalp region. Our findings may provide useful reference values for the histopathological evaluation of hair disorders in Asians.

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The Source and Mechanism of Normal Hair-Behaviour

10.4324/9781003251590-s9 ◽

2021 ◽

pp. 82-94

Author(s):

Charles Berg

Keyword(s):

Normal Hair

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Normal Hair-Behaviour

10.4324/9781003251590-s2 ◽

2021 ◽

pp. 4-8

Author(s):

Charles Berg

Keyword(s):

Normal Hair

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Deslorelin treatment of hyperoestrogenism in neutered ferrets (Mustela putorius furo): a case report

Veterinární Medicína ◽

10.17221/25/2009-vetmed ◽

2009 ◽

Vol 54 (No. 2) ◽

pp. 89-95 ◽

Cited By ~ 4

Author(s):

A. Prohaczik ◽

M. Kulcsar ◽

Gy. Huszenicza

Keyword(s):

Untreated Control ◽

Slow Release ◽

Clinical Signs ◽

Gnrh Analogue ◽

Mustela Putorius ◽

Blood Samples ◽

Nodular Hyperplasia ◽

Normal Hair ◽

Pre Treatment ◽

Subcutaneous Implant

Hyperoestrogenism causing progressive alopecia in neutered ferrets may be induced by ovarian remnant syndrome (ORS) and nodular hyperplasia of the adrenocortex (hyperadrenocorticism, NHA). The objective of the study was to determine whether a slow-release implant of a gonadotropin releasing hormone (GnRH) analogue, deslorelin, has any value in therapy of hyperoestrogenism of adrenocortical origin (NHA). Three supposed cases of NHA with alopecia and other clinical signs of hyperoestrogenism (n = 2 spayed females in oestrous and n = 1 castrated male) were treated with a subcutaneous implant of 4.7 mg deslorelin acetate. Blood samples were collected, and plasma levels of estradiol (E2) were determined just before, and some weeks after treatment. For realistic monitoring, blood samples for E2 determination were also taken from intact, healthy (untreated control) females after the beginning of heat (n = 5), or 9–21 days after, with hCG induced ovulation (n = 6), or out of breeding season (n = 3). Before treatment, all three alopecic ferrets showed elevated E2 concentrations (99.45–139.9 pmol/l) similar to the untreated control females in oestrous (61.6–123.02 pmol/l) (P = 0.229). Some weeks after the deslorelin administration, the hair of these ferrets began to grow again and the elevated E2 concentrations significantly decreased compared to the pre-treatment values (P = 0.035). E2 concentrations reached the basal level (12.89–16.08 pmol/l) typical for that of the untreated control females in anoestrus or in luteal phase (12.0–30.58 pmol/l) (P = 0.137). All treated ferrets were examined again 19–21 months after implant insertion (the implant still being present) and all of them had normal hair and were clinically healthy. These observations prove that deslorelin can suppress the E2 production of NHA, and is therefore a useful tool in the therapy of hormonal alopecia neutered ferrets.

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