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The Nutrition-Focused History and Physical Examination (NFPE) in Malnutrition
Published in Michael M. Rothkopf, Jennifer C. Johnson, Optimizing Metabolic Status for the Hospitalized Patient, 2023
Michael M. Rothkopf, Jennifer C. Johnson
Like the nails, hair is a skin appendage. It is a shaft of keratin formed by the hair follicle. The strength and character of the hair shaft is a function of nutritional status. Similarly, anchoring of the shaft at the follicle requires intact protein and micronutrients status. The sign you are looking for here is called “easy pluckability” of the hair shaft. Pulling on the hair will remove the shaft, often with a cellular matter attached. Ascorbic acid deficiency produces a specific set of findings with perifollicular hyperkeratosis, follicular hemorrhage and corkscrew hair strands.
Skin Disease
Published in John S. Axford, Chris A. O'Callaghan, Medicine for Finals and Beyond, 2023
Christopher Bunker, Richard Watchorn
In scarring alopecia, hair follicles are destroyed. Treatment aims to prevent further hair loss (Table 18.11; Figure 18.8; Figure 18.22; Figure 18.23). Tetracyclines are indicated in folliculitis decalvans and lichen planopilaris. Hydroxychloroquine is used in DLE.
Hair and hairy scalp
Published in Richard Ashton, Barbara Leppard, Differential Diagnosis in Dermatology, 2021
Richard Ashton, Barbara Leppard
This is hair loss occurring over the temples or on the crown due to androgens. The hair on the occiput and around the sides of the scalp is never lost. The effect of dihydrotestosterone is a shortening of the anagen growth phase and a corresponding increase in telogen hairs. Gradually, the hair follicles get smaller and terminal hairs are replaced by vellus hairs. The amount of hair loss and the age of onset is genetically determined (from mother or father).
Adnexal squamous cell carcinoma: incidence of eyelid margin involvement
Published in Orbit, 2023
Alison H. Watson, Sabah Akbani, Natalie Homer, Marie Somogyi, Vikram Durairaj
The eyelash follicle differs from other hair follicles in many ways. Notably, they are terminal hair follicles unlike the surrounding vellus follicles that are able to produce fully pigmented and medullated hair shafts.9 Unlike vellus hairs, they do not have arrector pili muscle and they are independent of sex hormones. Therefore, they are the darkest in the human body and the last to turn gray.9 There are limited identified studies of the lash follicle cycle in comparison to vellus hairs.9,13 One assessment postulated that the turnover cycle of these follicles is much longer than the vellus hairs.13 The predilection of SCC to develop along the marginal versus non-marginal eyelid may be a consequence of differences in the duration of the lash follicle life cycle, as this can influence the likelihood of malignant transformation.6,7
Effectiveness and safety of baricitinib in patients with alopecia areata: a systematic review and Meta-analysis of randomized controlled trials
Published in Current Medical Research and Opinion, 2023
An autoimmune condition known as alopecia areata (AA) affects people of all ages, both sexes, and skin types and results in non-scarring hair loss1. Although AA primarily affects the scalp, it can also injure other body parts that have hair2. Approximately 2% of people worldwide experience AA2,3. It has a negative impact on health-related quality of life, particularly in adults, and because of this, AA requires the same amount of attention as other common, chronic, dermatologic disorders like psoriasis and atopic dermatitis4–6. In AA, the immune privilege granted to hair follicles is lost, allowing CD+ 8 natural killer cells and CD+ 4 T cells to invade them. Interleukin-15, which interacts with Janus kinase (JAK)-1 and JAK3 on T cells, is released as a result of interferon-γ, which is secreted by CD8 + T cells. Interferon-γ communicates with Janus kinase JAK1 and JAK2 in the hair follicle epithelial cells. Hair loss and hair follicle damage follow2,7.
Recent advances in follicular drug delivery of nanoparticles
Published in Expert Opinion on Drug Delivery, 2020
Alexa Patzelt, Juergen Lademann
Follicular drug delivery with smart nanocarrier-based drug delivery systems represents a promising approach to increase the percutaneous absorption of topically applied substances and to increase their skin and systemic bioavailability. Several types of nanoparticles are available, which possess their own characteristics with regard to skin and hair follicle penetration and different physicochemical properties. The hair follicle itself is a complex and three-dimensional dynamic structure with several functions among which the reservoir and barrier functions are of special interest with regard to follicular penetration. The mechanism of the follicular penetration process has not been clarified in detail, yet, but seems to be predominantly mechanically driven. For a smart use of nanocarriers for drug delivery, strategies are necessary, which are able to overcome the skin barrier without disturbing it sustainably. Although many potential fields of application and technical achievements and efficacy proofs concerning an increased penetration of substances are already available, the practical implementation into clinical application still represents an additional challenge and should be the in focus of interest of future research.