Ageless Aesthetic Institute (courses in current skin procedures). 

Companies:  DermTech (noninvasive sticker for pealing off skin cells for meloma diagnosis)

The term “skin” refers to the outer protective covering of the body, consisting of the corium and the epidermis, including sweat and sebaceous glands, as well as hair follicle structures. Skin and oral musosae as well are composed to two primary layers, the outer epidermis, which is stratified epithelial tissue mainly composed of multiple layers of keratinocytes and the dermis, which is the layer beneath the epidermis consisting of connective tissue, blood vessel, immune cells, collagen and other components. Like the intestine, the epidermis of skin and oral musoca are self-renewing. The layers of the epidermis reflect the stages along the continuous process of keratinocyte maturation, from the basal layer adjacent the dermis which contains the proliferating stem and progenitor cells, to the outer protective layer of dead, cornified keratinocytes which are being sloughed form the surface. The cell division that occurs in the basal layer of the epidermis provides a continous source of keratinocytes which fully replenish the epidermis at rates that are estimated to be up to several weeks.

The skin, togetehr with the hair, nails and sweat and oil glands, forms the integument. 

Layers of the Skin

Epidermis: refers to the outermost and novascular layer of the skin, derived from the embryonic ectoderm, varying in thickness from 0.07-1.4 mm. The epidermis is a complex epithelial tissue containing keratinocytes that are proliferating, differentiating and desquamating, and is stratified such that morphological functional changes in the keratinocytes occur in an orderly progression. The normal epidermis is maintained in a dynamic steady state as proliferation of keratinocytes continually compensates for the loss of cells which are shed from the surface of the skin. Within the epidermis, proliferation takes place in the basal layer of keratinocytes that are attached to the underlying basement membrane, and cells undergo differentiation as they migrate through the suprabasal layers, finally being shed from the tissue surface as dead, cornified squames. Three subpopulations of basal keratinocytes have been defined by cell kinetic analysis: stem cells, transit-ampliyfing cells, and committed cells.

Skin cells which make up the epidermis include Merkel cells, keratinocytes, melanocytes and Langerhans cells.

Dermal-epidermal Junction (DEJ): is a critical component of the skin and is composed of a netword of structural proteins that provide a firm connection between the basal keratiocytes of the epidermis and the dermis. This structural network is made up of (1) the hemidesmosome-anchoring filament complex; (2) the basement membrane comprising two layers, the lamina lucida and the lamin densa and (3) anchoring fibrils.

Corium or Dermis: refers to the layer of the skin deep to the epidermis, consisting of a dense bed of fascular connective tissue, and containing the nerves and terminal organs of sensation. The hair roots (follicles), and sebaceous and sweat glands are structures which are also embedded in the dermis.

The dermis is a rich matrix of fibroblast cells and fibers such collagen, and it contains macrophages and mast cells. The dermis also habors a dense network fo nevers, blood vessels, and lymphatic vessels. Damage to the epidermis generally does not result in bleeding, whereas damage deep enough to penetrate the dermis results in broken blood vessels. 

Sebaceious (oil) glands and scent glands are associated with the hair follicle. All of these glands have opening on the surface of the skin, so they pass through the epidermis as well. The sebasceous glands secretion, celld sebum, has a low pH, hwicch makes the skin inhospitable to many microorganisms. Sebum is oily due to its high concentraiton of lipids. The lipids can serve as nutrients for normal microbiota, but breakdown of the fatty acids contained in lipids, leads to toxic by products that inhibit the growth of microorgansms not adapted to the skin environment. Lysozyme is an enzyme found in sweat (and tears and saliva) that specifically breaks down peptidoglycan, found in bacterial cell walls. 

Blister fromation, the result of friction trauma or burns, represents a separation between the dermis and epidermis. 

Age Spots: 

As the skin ages, the division rate of skin cells slows down causing an overall reduction in the number of cells and blood vessels that supply nutrients and other necessary building blocks for the skin resulting in a decrease in the thickness of the epidermis. Collagen and elastin fibers in the underlying layers of skin which provide the scaffolding for the surface layers begin to weakn and deteriorate.

Products with retinoids, alpha-hydroxy acids, azaleic acid, hydroquinone, kojic acid, salicylic acid as active agredients have all shown to make the skin appear younger. 

Hydroquinone, an over-the-counter drug that can bleach your skin, may fade dark spots. Retinoids may make your skin tone more even. One study says vitamin C helps fade age spots when you use it for 12 weeks. Kojic acid — a chemical that’s often used as an skin-whitening ingredient in products — can also help with age spots..

Contact Dermatitis

Allergic contact dermatitis is a delayed hypersensitivity reaction in which a foreign substance comes into contact with the skin; skin changes occur with reexposure. Allergic contact dermatitis is caused by a type IV, T cell–mediated, delayed hypersensitivity reaction in which a foreign substance comes into contact with the skin and is linked to skin protein, forming an antigen complex that leads to sensitization. Upon reexposure of the epidermis to the antigen, the sensitized T cells initiate an inflammatory cascade, causing the skin changes associated with allergic contact dermatitis.  

Common substances that cause contact dermatitis include poison ivy, nickel, and fragrances.

Allergic contact dermatitis is a common eczematous skin disease that occurs in sensitized individuals at the site of contact with small chemicals penetrating the skin barrier. The onset of the disease is mostly due to the rapid recruitment of chemical-specific CD8+ T cells, which induce apoptosis of keratinocytes. Additionally, CD4+ Th1 and Th17 contribute to the extension of the inflammatory reaction by releasing pro-inflammatory cytokines that activate keratinocytes and other skin resident cells. The immune reaction is tightly regulated through multiple mechanisms. In particular, T cell population with regulatory function, such as T regulatory cells 1 and CD4+CD25+ T regulatory cells have a critical role in preventing the development of allergic reactions to innocuous chemicals contacting the skin, and in limiting the magnitude of the inflammatory process in already sensitized individuals. Allergic contact dermatitis is a chronic disease, which lasts, in most cases, for the entire life of the affected individual. Thus, prevention and avoidance of contact with the sensitizer are critical factors in the management of affected patients.

The gold standard therapeutic approach for the disease remains the local and/or systemic immunosuppression, aimed to block T cell functions and keratinocyte responsiveness to pro-inflammatory stimuli. Localized acute allergic contact dermatitis lesions are successfully treated with mid- or high-potency topical steroids, such as triamcinolone 0.1% (Kenalog, Aristo- cort) or clobetasol 0.05% (Temovate). 

Eczema:

Eczema is an umbrella term for different kinds of skin inflammation. It is marked by dry, reddened skin that itches or burns. When skin becomes dry and irritated in winter, eczema can flare.  Stay one step ahead by moisturizing frequently with an oil-based ointment that contains sunscreen. Sweating and overheating can also trigger the itch/scratch cycle, so dress in easy-to-peel-off layers. 

Psoriasis:

Psoriasis is more than dry skin. It’s caused when the immune system misfires and speeds up skin cell growth. Dry air, lack of sunlight, and colder weather can make it worse. Follow tips for dry skin: short, lukewarm showers, lots of moisturizer, and humidifiers throughout the house. Ask your dermatologist about phototherapy, which uses ultraviolet light B (UVB) rays to slow the growth of skin cells, and about the best treatments for you.

Particular Regions of the Skin

Face/Body: 

–Washing/Shower: Choose a gentle, super-fatted, fragrance-free soap — bar or liquid — for cleansing. Super-fatted means the soap is loaded with oils. If skin is dry, moisturizers that contain urea, dimethicone, glycerin, lanolin, or mineral oil can be good bets.

Humectants — like urea, glycerin, hyaluronic acid, propylene glycol — absorb water from the air. They are oil-free. Emollients — like baby or mineral oil, plant oils (like jojoba oil), petroleum jelly, lanolin, stearic acid — help replace oils in the skin. Many moisturizers contain a combination. You may want to skip some anti-aging moisturizers in winter. Those that contain retinoids can further irritate already dry, sensitive skin.

–After Shower:

Ointments — like petroleum jelly — have more oil than creams or lotions. That makes them more greasy, too, so they may be best for feet and body. Minimize the greasy feeling by using a very small amount and gently but thoroughly rubbing it into skin. Apply after a warm shower. 

Right after you step out of the tub, pat skin dry and apply moisturizer to retain the water your skin just absorbed. A glycerin– or hyaluronic acid-based moisturizer can increase the amount of water that’s drawn into your skin. Baby oil (mineral oil) is also a good choice, because it prevents water from evaporating from your skin. Don’t stop there: Liberally re-apply moisturizer throughout the day, especially to troublesome dry skin patches.

To get the most out of your moisturizer, exfoliate. Clearing away dead skin cells lets a moisturizer better penetrate dry skin. Exfoliate gently with a moisturizer that contains lactic acid or salicylic acid. Some exfoliants can be irritating, especially in winter, so try them on a small patch of skin first. If your skin is really dry or irritated, ask your doctor before starting a new skin care product or regimen.

If its cold outside and you have the heat on, dry air can mean parched, dry skin. Use a humidifier to restore moisture to the air. You can find inexpensive models at most drug stores. Put one in your bedroom; better yet, invest in two or three and place them strategically around your home to stave off irritated, itchy skin this winter.

Apply sunscreen if you will be outside, even in cold climates. Skiers and other winter athletes are at special risk of sunburn because snow reflects sunlight. In fact, it bounces 80% of the sun’s rays back to us, compared to less than 20% for sand and surf. Even if you’re not hitting the slopes, you still need the protection of a sunscreen with an SPF of 30 or more. Apply daily, and reapply at least every two hours if you’re outside.

Feet: Mature skin makes less oil and elastin, which leaves it drier and less supple. Without regular care, your heels may harden, crack, or hurt. Special creams called keratolytics help slough off the tough top layer. Follow up with a pumice stone to remove dead skin. 

Skin Tightening:

Radiofrequency: WebMD

Plants and Cosmetics:

The trend of natural cosmetics production has ushered in an era of plant cell culture technology with mroe than 50 cosmetic products based on extracts of plant cell cultures, the bulk of which are made with plant cell suspension cultures. Plant cell culture cosmetic production is not dependent on appropriate seasonal conditions; thus it requries less time and eerngy. Cosmetic extracts dervied from plant cell cutlures suit the market’s increasingly stringent safety requirements. In addition to being free of pathogens, pollutants and pesticide residues, plant cells generated under aseptic laboratory conditions rarely include any malignant cmopound or potential allergen which would otherwise destroy the majority of the plant extrats obtained. Plant cell suspension cultures are cultivated in single-use wave-mixed bioreactors or renwable stainless stell stired bioreactors in commerical production. (Hasnain, “Plants in vitro propagation with its applicaitons in food, pharmaceuticals and cosmetic industries; current scenario and future approaches” Frontiers in Plant Science 2022)

Applicaitons of palnts/flower extracts in cosmetics are significant which include skin oisturing, whitening or tanning products, sunscreens, radical-scavenging antioxidcants, immune stimulants and skin thickeners. (Hasnain, “Plants in vitro propagation with its applicaitons in food, pharmaceuticals and cosmetic industries; current scenario and future approaches” Frontiers in Plant Science 2022)

Raspberry (Rubus ideaus): has been shown to exhibit extraordianry capacity to hydrate skin when tested on human skin in vivo, indcating taht it has tremendous portential as a skin care agent, particularly for dry and ageing skin. (Hasnain, “Plants in vitro propagation with its applicaitons in food, pharmaceuticals and cosmetic industries; current scenario and future approaches” Frontiers in Plant Science 2022)