ABSTRACT
Interest in sebaceous gland functioning and its diseases is increasing. This article provides a summarized update of the current knowledge of the pathophysiology of acne vulgaris and the new treatment concepts that have emerged in recent years. Recent literature is reviewed regarding teenage acne, focusing on pathogenesis, associations, controversies and considerations in therapy to further help practitioners stay current on the issues regarding this topic. Current research is expected to provide new and improved treatments in the near future.
Subject(s)
Acne Vulgaris/physiopathology , Acne Vulgaris/epidemiology , Acne Vulgaris/etiology , Acne Vulgaris/psychology , Acne Vulgaris/therapy , Adolescent , Animals , Anti-Bacterial Agents/therapeutic use , Bacterial Vaccines/therapeutic use , Botulinum Toxins, Type A/therapeutic use , Combined Modality Therapy , Dermatologic Agents/therapeutic use , Diet/adverse effects , Exercise , Forecasting , Humans , Hygiene , Low-Level Light Therapy , Mice , Puberty , Sebaceous Glands/physiopathology , Severity of Illness IndexABSTRACT
A number of lasers and light devices are now available for the treatment of unwanted hair. The goal of laser hair removal is to damage stem cells in the bulge of the hair follicle by targeting melanin, the endogenous chromophore for laser and light devices utilized to remove hair. The competing chromophores in the skin and hair, oxyhemoglobin and water, have a decreased absorption between 690 nm and 1000 nm, thus making this an ideal range for laser and light sources. Laser hair removal is achieved through follicular unit destruction based on selective photothermolysis. The principle of selective photothermolysis predicts that the thermal injury will be restricted to a given target if there is sufficient selective absorption of light and the pulse duration is shorter than the thermal relaxation time of the target. This review will focus on the mechanisms of laser assisted hair removal and provide an update on the newer technologies emerging in the field of lasers assisted hair removal.
Subject(s)
Hair Removal , Lasers , Hair Removal/adverse effects , Hair Removal/methods , Humans , Lasers/adverse effectsABSTRACT
Contact hypersensitivity (CHS) is a dendritic cell (DC)-dependent T-cell mediated cutaneous inflammatory reaction elicited by epicutaneous exposure to reactive chemicals, known as haptens, from cosmetic products or through environmental and occupational exposures. The best-studied haptens are low molecular weight chemicals (<1,000) that bind discrete amino acid residues on self or exogenous proteins/peptides in the skin and become immunogenic. Clinically, CHS typically occurs as a delayed type of allergic contact dermatitis. Haptens penetrate the skin and bind to self proteins to form complete antigens which are taken by antigen presenting cells to start a cascade of actions resulting in a delayed hypersensitivity reaction. Larger molecules such as proteins induce response involving the humoral immune system. The environment at the time of antigen presentation affects the innate immune system which in turn influences the expression of CHS. The subsequent immunologic response (or lack thereof) is a result of complex interaction between both the innate and the adaptive immune systems. This interaction results in either an inflammatory immune response or tolerance.
