Pilosebaceous unit

The pilosebaceous unit of the skin consists of a hair follicle and the surrounding sebaceous glands. An initial acne lesion called a comedo forms when there is a blockage in the pilosebaceous unit.8... 

Whitmore, SE. Disorders of the pilosebaceous unit Acne and related disorders and hair loss. In Barker LB, Burton JR, Zieve PD, et al, eds. Principles of Ambulatory Medicine. 6th ed. Philadelphia Lippincott Williams 8c Wilkins, 2003 1740-1746. 

Erythromycin in concentrations of 1% to 4% with or without zinc is effective against inflammatory acne. Zinc combination products may enhance penetration of erythromycin into the pilosebaceous unit. 

Anti -acne. Preventing the inflammatory disease of the pilosebaceous unit. Anti-amoebic. Destroying or suppressing the growth of amoebae. Anti-ancylostomiasis. Preventing the infection with hookworms of the genus Ancyclostoma. 

Acne vulgaris affects the pilosebaceous units to the skin, leading to their eventual blockade and development of acne lesions. Abnormal desquamation, defective keratinisation, blockade of the follicular orifice and collection and colonization of sebum lead to proliferation of Propionibacterium acnes. 

Effects on the pilosebaceous unit Perioral dermatitis (SEDA-5, 151)... 

Liposomes applied on the skin were also investigated for their delivery proprieties to the pilosebaceous units [15,23 28]. The in vitro skin penetration behavior of carboxyfluorescein incorporated in multilamellar liposomes (phosphatidylcholine cholesterol phosphatidylser-ine) and in another four nonliposomal systems (HEPES pH 7.4 buffer 5% propylene glycol 10% ethanol and 0.05% sodium lauryl sulfate) was studied by Lieb et al. [25]. Using two fluorescent techniques the authors found a higher accumulation of the probe within skin follicles when delivered from liposomes [25], Further, in an interesting setup of in vitro and in vivo experiments in mice, Hoffman s group observed liposomal delivery of the active Lac-Z gene and its expression mostly in the hair follicles [26,28]. 

Lieb, L.M., G. Flynn, and N. Weiner. 1994. Follicular (pilosebaceous unit) deposition and pharmacological behavior of cimetidine as a function of formulation. Pharm Res 11 1419. 

Lieb, L.M., et al. 1992. Topical delivery enhancement with multilamellar liposomes into pilosebaceous units I. In vitro evaluation using fluorescent techniques with the hamster ear model. J Invest Dermatol 99 108. 

Niemiec, S.M., C. Ramachandran, and N. Weiner. 1995. Influence of nonionic liposomal composition on topical delivery of peptide drugs into pilosebaceous units An in vivo study using the hamster ear model. Pharm Res 12 1184. 

A woman had received intralesional paramethasone and other topical glucocorticoids several times for alopecia between the ages of 7 and 18 years (381). When she was 30 she was again treated with intralesional paramethasone for a relapse of alopecia. She developed pruritus after the first intralesional injection and erythema, edema, and vesicles 6-8 hours later. A biopsy showed spongiform lymphocytic folliculitis with spongiosis and exocytosis in the sweat gland ducts and in the pilosebaceous unit. She was treated with triamcinolone cream and her skin lesions resolved. Patch tests were positive for paramethasone, with cross-reactivity to tixocortol pivalate, hydrocortisone, and hydrocortisone butyrate. 

Acne vulgaris is the result of several factors combined. The condition arises in the pilosebaceous units in the dermis, which consist of a hair follicle and associated sebaceous gland. These glands secrete sebum, a mixture of fats and waxes that protect the skin and hair by retarding water loss and forming a barrier against external agents. The hair follicle is lined with epithelial cells that become keratinised as they mature. 

Help the pilosebaceous units drain glycolic acid, lactic acid, retinyl pahnitate, glycyrrhetinic acid and azelaic acid. 

In addition to all the structural changes that can follow exposure to ionizing radiation, there is a possibility that the pilosebaceous units might atrophy. This would delay epidermal regeneration and promote the formation of nasty... 

After an intraepidermal peel, to the basal layer or the Grenz zone, the skin regenerates from leftover islets of ker-atinocytes. In the case of a deep peel, the skin regenerates from its appendages. The face has more pilosebaceous units than the neck, and facial skin regenerates more quickly, with less risk of scarring. 

The product should only be applied to the face. There is a large number of pilosebaceous units here that help the epidermis regenerate properly. 

Phenol is not toxic to the pilosebaceous units. To avoid creating a visible demarcation line between the skin of the forehead and the hair, the applicator is taken 1 cm into the anterior hairline. 

Skin repair after a peel to the reticular dermis is slower, as all the basal layer keratinocytes have been destroyed and the skin can only rely on the differentiated keratinocytes of the pilosebaceous units and the intradermal excretory ducts of the sweat glands. To repair the dermis, the sebocytes in the pilosebaceous units must dedifferentiate, and horizontal growth is required to close the skin quickly. Next comes a phase of vertical growth whose purpose is to regenerate a physiologically sound epidermis that will maintain homeostasis and restore the vital barrier function after the keratinocytes have differentiated into corneocytes. 

Acne vulgaris is a disease of the pilosebaceous unit (i.e., the sebaceous glands and adjacent hair follicle). 

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