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Systemic disease and the skin
Published in Rashmi Sarkar, Anupam Das, Sumit Sethi, Concise Dermatology, 2021
The condition is almost always a sign of Rebreak thyro-toxicosis and is accompanied by exophthalmos. It occurs in 5% of patients with thyrotoxicosis. It is persistent and difficult to treat, although treatment with PUVA is sometimes successful. Rarely, there is diffuse infiltration with the similar mucinous connective tissue of the hands and feet and finger clubbing in the condition of thyroid acropachy. Patients with thyrotoxicosis have warm, sweaty skin, and some complain of pruritus. There is a diffuse loss of scalp hair in some patients.
Dermatomycoses
Published in Raimo E Suhonen, Rodney P R Dawber, David H Ellis, Fungal Infections of the Skin, Hair and Nails, 2020
Raimo E Suhonen, Rodney P R Dawber, David H Ellis
The conidia of the ringworm fungi that cause tinea capitis can be demonstrated in the atmosphere close to the scalp of patients with the condition. It is highly likely that scalp hair acts as a trapping device, possibly enhanced by electrostatic forces. It is known that contamination of hair without any clinical signs may occur among classmates of children with tinea capitis. It has also been demonstrated that, if actual hair infection is to occur, the stratum corneum of the scalp skin must first be invaded. Trauma assists inoculation.
Geriatric hair and scalp disorders
Published in Robert A. Norman, Geriatric Dermatology, 2020
Hair follicle activity is intermittent and characterized by a growth phase (anagen), followed by a brief transition phase (catagen) and a resting phase (telogen). Normally 90% or more of scalp hair is in the anagen phase at any given time, 10% or less is in the telogen phase and less than 1% is in catagen. The anagen phase is determined genetically and differs in individuals. The length of the anagen phase determines the natural length an individual’s hair will attain and tends to remain stable unless pathologic alterations intervene. Telogen hairs are also retained for a defined period of time and then shed. On the scalp, telogen hairs are held 2–3 months before they are shed. The follicles in different anatomic sites vary in duration of anagen and telogen phase, which gives hair its growth characteristics by site. Those areas with long anagen cycles and a short telogen phase, such as scalp hair, produce a long fiber. A short anagen growth phase, coupled with a prolonged telogen phase, produces the shorter, stable hairs of the eyebrows and eyelashes, and the terminal hairs on the extremities. Scalp hair grows at approximately one centimeter a month, although the growth rate slows down with advanced age.
EthoLeciplex: a new tool for effective cutaneous delivery of minoxidil
Published in Drug Development and Industrial Pharmacy, 2022
Mohammed Elmowafy, Khaled Shalaby, Nabil K. Alruwaili, Mohammed H. Elkomy, Ameeduzzafar Zafar, Ghareb M. Soliman, Ayman Salama, Elsaied H. Barakat
Alopecia is a case in which hairs are abnormally lost due to different reasons such as genetic problems, healthy condition, stress and aging [1,2]. It has been considered as a public illness that several people are suffering all over the world [3]. Specifically, androgenic alopecia is a genetic disease manifested by thinning of scalp hair due to androgenic effect. US Food and Drug Administration approved two medications for controlling progressive loss the scalp hair associated with androgenic alopecia; administration of finasteride orally (1 mg/day) and topical application of minoxidil (MX) (2% and 5% solutions) [4]. MX, chemically identified as 2,4-diamino-6-piperidinopyrimidine 3-oxide, mechanism of action is not fully understood but it was reported to prolong the anagen stage by stimulating β-catenin through antiapoptotic effect in the dermal papilla cells of hair follicle [5]. As MX is suffering from low solubility, selecting of appropriate vehicle/carrier is a challenge. Commercially, MX topical solution is available in concentrations of 2% and 5% dissolved in mixture of propylene glycol/water/ethanol (Rogaine®, Pfizer). Though the dissolving mixture is capable of dissolving the required dose of MX, it possesses several drawbacks such as skin dryness, skin burning and eye irritation due to presence of organic solvent [6]. Several approaches have been implemented to improve skin/transfollicular delivery of MX such as microemulsion [7], chitosan nanoparticles [8], poly(lactide-co-glycolide)-grafted hyaluronate nanoparticles [9], lecithin-based microparticles [10] and solid effervescent formulations [11].
A validation study on fingernail cortisol: correlations with one-month cortisol levels estimated by hair and saliva samples
Published in Stress, 2021
Shuhei Izawa, Nagisa Sugaya, Namiko Ogawa, Kentaro Shirotsuki, Shusaku Nomura
Acute psychosocial stress triggers the activation of the hypothalamic-pituitary-adrenal axis. In response, the cortisol levels in blood and saliva increase 20–40 min from the onset of acute psychological stress (Dickerson & Kemeny, 2004). Cortisol levels measured in hair samples are an index of cumulative hormone levels. Scalp hair grows at an average rate of 1 cm/month; therefore, 1 cm of scalp hair could be used to measure hormone levels in 1 month (Russell et al., 2012). Hair cortisol levels are associated with saliva cortisol levels (Short et al., 2016; Sugaya et al., 2020), and chronically stressed people (e.g. dementia caregivers, unemployed men) exhibited elevated hair cortisol levels (Dettenborn et al., 2012; Stalder et al., 2014). While saliva and blood samples revealed hormone levels over a short period and exhibited large diurnal variations with higher levels in the morning and lower levels in the afternoon, hair samples provide an index of cumulative hormone exposure over a longer period, which informs the investigation of cortisol levels and chronic stress.
Impact of progesterone on skin and hair in menopause – a comprehensive review
Published in Climacteric, 2021
S. Gasser, K. Heidemeyer, M. von Wolff, P. Stute
For therapeutic reasons, micronized progesterone (MP) can be used, for example, for endometrial protection when estrogens are applied in menopausal women with an intact uterus7. While the current indications for menopausal hormone therapy (MHT) include menopausal symptom relief, and osteoporosis prevention8,9, MHT has also been shown to have an impact on both skin development and composition10, and to slow the aging process of female skin after menopause11,12. Skin aging is due to extrinsic factors (e.g. smoking, pollution, ultraviolet radiation) and intrinsic factors (e.g. genetics, inflammation, hormonal imbalance), respectively13. Thus, many women experience a sudden onset of skin aging signs during menopause, such as an increase in skin dryness, loss of firmness, decrease in elasticity, wrinkles, and dyspigmentation14. Menopause-related hormonal changes also have an impact on scalp hair, such as a reduction of the hair diameter and a faster switch from the anagen to telogen phase, leading to a shorter hair growth phase15. Thus, scalp hair appears as being in a state of chronically increased hair loss. In cases of prevalent female pattern hair loss (androgenic alopecia), menopause promotes the miniaturization of the hair follicle. By age 50 years, a quarter of all women are affected by female pattern hair loss16,17.