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1.
J Am Acad Dermatol ; 89(4): 758-763, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-30630022

RESUMO

Alopecia areata (AA) is a common form of nonscarring hair loss. It is believed to be a consequence of an immune-mediated stimulus, probably involving autoreactive T cells against antigens present in the hair follicle. The exact antigen is still unknown; however, some authors have proposed that melanogenesis-associated molecules might trigger autoimmunity. Although transient white hair regrowth is a common and well-known situation in AA, there are other types of white hair phenomena in this context, including permanent white hair regrowth, sparing of white hair in a patchy pattern, or sparing in a diffuse pattern, giving the appearance of the so-called overnight graying phenomena or canitis subita. In this review, we aim to describe the different clinical aspects of white hair in AA, as well as the proposed pathophysiologic mechanisms involved in this phenomena.


Assuntos
Alopecia em Áreas , Doenças do Cabelo , Humanos , Folículo Piloso/patologia , Doenças do Cabelo/patologia , Cor de Cabelo
2.
J Cutan Pathol ; 46(7): 508-519, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30932205

RESUMO

Hair follicles experience several changes with aging, the most noticeable of which is graying of the hair shaft due to loss of melanin. Additional changes in the diameter and length of the hair have contributed to the concept of senescent alopecia, which is different from androgenetic alopecia according to most. Graying happens in most individuals, although in different grades and starting at different ages. It is related to a decrease in the number and activity of the melanocytes of the hair bulb, which eventually completely disappear from the bulb of the white hair. Residual non-active melanocytes remain in the outer root sheath and in the bulge, which allows for repigmentation of the hair under certain stimuli or conditions.


Assuntos
Envelhecimento/metabolismo , Alopecia/metabolismo , Cor de Cabelo , Folículo Piloso/metabolismo , Melaninas/metabolismo , Melanócitos/metabolismo , Envelhecimento/patologia , Alopecia/patologia , Feminino , Folículo Piloso/patologia , Humanos , Masculino , Melanócitos/patologia
3.
Skin Res Technol ; 25(4): 517-525, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30758871

RESUMO

BACKGROUND: The main objective of this study was to determine the lipid profile of brown and white Caucasian hair fibres and the effects of lipids on the properties of fibres. MATERIALS AND METHODS: To determine the structures of white and brown hair lipid bilayers, cross sections of fibres of both hair types were examined using synchrotron-based µ-FTIR mapping. Dynamic vapour sorption (DVS) analyses were also performed to determine the differences in the barrier function of both fibres. RESULTS: Spatial identification of lipids showed that a great amount of lipids was present in the medulla of fibres of both hair types, but important differences were also observed between cuticles of the different fibres. The cuticle of a white hair fibre showed a significant decrease in its lipid content, but did not show differences in the lateral packing order with respect to the cuticle of a brown hair fibre. The cortex and medulla of the white hair fibre also exhibited a significant decrease in its lipid content but with a higher lateral packing order than brown hair. Using DVS analysis, it was found that the water dynamics of white hair fibres differed from those of brown hair fibres, showing a decrease in their total capacity to absorb water and an increase in the velocity of the exchange of water with the environment. CONCLUSION: The results of both techniques demonstrated a high correlation between the characteristics of the lipids located in the cuticle and the water dynamics of the fibres.


Assuntos
Cor de Cabelo , Cabelo , Espectroscopia de Infravermelho com Transformada de Fourier , Água , Humanos , Cabelo/química , Cabelo/fisiologia , Cabelo/ultraestrutura , Cor de Cabelo/fisiologia , Hidrodinâmica , Metabolismo dos Lipídeos , Lipídeos/sangue , Espectroscopia de Infravermelho com Transformada de Fourier/instrumentação , Síncrotrons , Água/metabolismo
4.
Lasers Surg Med ; 48(8): 748-762, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27504592

RESUMO

BACKGROUND AND OBJECTIVE: Lasers have been successfully used for decades to remove dark hair. However, laser removal of nonpigmented hair is challenging due to the lack of chromophores. The aim of this study was to use photodynamic therapy (PDT) to remove nonpigmented hair. STUDY DESIGN/MATERIAL AND METHODS: We compared the efficacy of permanent hair reduction in white BALB/c and black C57BL/6 mice treated with PDT or an 800-nm diode laser. We collected skin biopsy specimens and investigated post-PDT histologic changes and molecular changes. RESULTS: We observed keratin 15 staining in the bulge area and alkaline phosphatase staining in the dermal papilla following PDT. We observed a temporary, catagen-like transformation in nonpigmented hair follicles after PDT. We observed apoptotic cells in the hair matrix after PDT. Irradiation with an 800-nm diode laser did not achieve nonpigmented hair removal. Multiple PDT sessions achieved permanent reduction of nonpigmented hair. Interestingly, removal of black hair using PDT was less efficient. CONCLUSION: Our results suggest that PDT can damage the nonpigmented hair matrix, but not stem cells or dermal papillae. Repeated PDT may impair the hair-regeneration capacity via a bystander effect on bulge stem cells or dermal papillae. In this study, we found it was possible to remove nonpigmented hair using PDT. Lasers Surg. Med. 48:748-762, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Ácido Aminolevulínico/análogos & derivados , Cor de Cabelo , Remoção de Cabelo/métodos , Fotoquimioterapia , Fármacos Fotossensibilizantes/uso terapêutico , Ácido Aminolevulínico/uso terapêutico , Animais , Feminino , Lasers Semicondutores/uso terapêutico , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Resultado do Tratamento
5.
Aesthet Surg J ; 34(2): 298-305, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24408514

RESUMO

BACKGROUND: Topical Cyperus rotundus oil is an effective and safe method to decrease hair growth. The oil's flavonoids have antiandrogenic activity on androgenic hair. To date, there have been no randomized controlled trials comparing topical C rotundus oil to the available allopathic modalities, such as laser-assisted hair removal. OBJECTIVES: In an open-label pilot study, the author prospectively evaluated the efficacy of C rotundus essential oil, compared with the Alexandrite laser (GentleLase; Candela Laser Corp, Wayland, Massachusetts) and saline, for reducing unwanted axillary hair. METHODS: Eligible participants (n=65) with unwanted axillary hair were assigned randomly to 1 of 3 study groups: topical C rotundus oil (group 1), saline (group 2), and Alexandrite laser (group 3). Sixty patients completed the entire study. Three methods were used to evaluate the results: hair counts, observations of independent professionals, and patient self-assessments. RESULTS: Overall results did not differ significantly between C rotundus oil and the Alexandrite laser (P>.05). However, statistically significant differences were noted with respect to decreased growth of white hair (P<.05), favoring the oil. This finding was evident by all 3 methods of assessment. No side effects were detected. CONCLUSIONS: Cyperus rotundus essential oil is as effective as the Alexandrite laser for decreasing the growth of axillary hair (both dark and white). LEVEL OF EVIDENCE: 3.


Assuntos
Cyperus , Remoção de Cabelo/métodos , Terapia com Luz de Baixa Intensidade , Fitoterapia , Óleos de Plantas/uso terapêutico , Administração Tópica , Adolescente , Adulto , Axila , Feminino , Humanos , Lasers de Estado Sólido , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Adulto Jovem
6.
J Cosmet Dermatol ; 23(7): 2490-2495, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38500297

RESUMO

BACKGROUND: There is a strong correlation between alopecia areata (AA) and the development of white hair. The AA presents itself in many clinical manifestations of depigmented hair as the condition advances. It is uncommon for unpigmented hair to extensively regrow for more than one hair growth cycle in AA and successful conversion to pigmented hair after treatment has not yet been reported. AIM: We report two case studies involving the persistent regrowth of white hair after AA that became pigmented through treatment. PATIENTS: In the first case study, a 47-year-old woman with AA exhibited a fully regrown head of hair, which remained unpigmented. However, after 2 years of treatment with oral methylprednisolone and compound glycopyrrolate, her hair eventually regained its normal pigmentation. In the second case study, a 7-year-old boy with diffuse AA received compound glycyrrhizin (50 mg once daily) and methylprednisolone (4 mg orally once daily) for 3 years. RESULTS: The both patients experienced regrowth of black hair on his entire head, with occasional white hairs. It is hypothesized that the aforementioned medications may regulate immunity by influencing melanocytes or melanin-associated antigens; however, the precise mechanism must be validated through additional histopathological and molecular analysis. CONCLUSION: A larger patient group, possibly in randomized controlled trials, is needed to determine how the indicated treatment affects hair repigmentation after AA. Therefore, more patients must be included for more substantial outcomes from this study.


Assuntos
Alopecia em Áreas , Cor de Cabelo , Metilprednisolona , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Alopecia em Áreas/tratamento farmacológico , Alopecia em Áreas/patologia , Cabelo/crescimento & desenvolvimento , Cabelo/efeitos dos fármacos , Cor de Cabelo/efeitos dos fármacos , Metilprednisolona/administração & dosagem
7.
Cureus ; 16(5): e59994, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38854262

RESUMO

Premature graying of hair (PGH) is a multifactorial condition defined by the graying of hair before the age of 20 in Caucasians and before the age of 30 in African Americans. Although the etiology remains unknown, it has been associated with genetic predisposition, oxidative stress, nutritional deficiencies, and autoimmune diseases. Current treatment options are limited but can include anti-inflammatory medications, vitamins, and hair colorants for symptom control. In this report, we present a case of premature graying in a 32-year-old male, onset at age 15, exhibiting a distinctive fractal pattern. This case represents a unique instance of PGH characterized by an unusual pattern, necessitating further investigation into potential etiological factors and underlying pathophysiological mechanisms.

8.
Forensic Sci Int ; 301: 67-75, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31129374

RESUMO

In order to investigate the influence of pigmentation on the incorporation of drugs into hair, time-course changes in drug distribution along non-pigmented (white) hairs as well as pigmented (black) hairs plucked from the same subject was observed following single administrations of two basic drugs with different properties, zolpidem and methoxyphenamine. These drugs in 1-mm sections of single hair specimens were each determined by a liquid chromatography-tandem mass spectrometric procedure. During the early stage (12-36 h) after intake, for black hairs, both drugs were detected over the entire area of hair root (4-5 mm in length), in which notable concentration of these drugs in the hair bulb (0-1-mm segment from the bottom of hair root, Region 1) and lower concentrations in the upper dermis zone (1-2-mm to 3-4-mm or to 4-5-mm segments, Region 2) were commonly observed. Meanwhile, for white hairs, high drug concentrations in Region 1 as detected in black hairs were not observed although only small amounts of these drugs were detected over Region 2. Subsequent time-course changes in the concentration of drugs in hair demonstrated that the drugs once incorporated into white hair via Region 2 decreased gradually over the period from 24 h to 35 days after intake, but those of black hairs remained almost unchanged. These findings revealed here suggest that hair pigments have two important roles in the distribution of drugs: (1) incorporation of drugs into hair via Region 1, and (2) retention of already incorporated drugs in the hair tissue. These findings would be useful for discussing individual drug-use history based on hair analysis in the forensic fields.


Assuntos
Cor de Cabelo , Cabelo/química , Metanfetamina/análogos & derivados , Zolpidem/análise , Cromatografia Líquida , Toxicologia Forense , Humanos , Hipnóticos e Sedativos/análise , Masculino , Metanfetamina/análise , Pessoa de Meia-Idade , Entorpecentes/análise , Detecção do Abuso de Substâncias/métodos , Espectrometria de Massas em Tandem , Fatores de Tempo
9.
Int J Trichology ; 10(5): 198-203, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30607038

RESUMO

Premature graying of hair (PGH) is defined as graying of hair before the age of 20 years in Caucasians and before 30 years in African American population. It can severely affect the self-esteem of an individual. The exact etiopathogenesis remains unknown, although it has been associated with premature aging disorders, atopy, and autoimmune diseases. Patients, who present with PGH, should be assessed for syndromes and metabolism diseases. Hair dyes remain the main modality of the treatment for cosmetic concerns after nutritional supplementation.

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