1.
Cosmetics
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Cosmetics, also known as make-up, are substances or products used to enhance or alter the appearance or fragrance of the body. Many cosmetics are designed for use of applying to the face and they are generally mixtures of chemical compounds, some being derived from natural sources, and some being synthetics. Common cosmetics include lipstick, mascara, eye shadow, foundation, rouge, skin cleansers and skin lotions, shampoo, hairstyling products, perfume and this broad definition includes any material intended for use as a component of a cosmetic product. The FDA specifically excludes soap from this category, Egyptian women and men also used makeup. They were very fond of eyeliner and eyeshadows in dark colors including blue, red, Ancient Sumerian men and women were possibly the first to invent and wear lipstick, about 5,000 years ago. They crushed gemstones and used them to decorate their faces, mainly on the lips, also around 3000 BC to 1500 BC, women in the ancient Indus Valley Civilization applied red tinted lipstick to their lips for face decoration. Ancient Egyptians extracted red dye from fucus-algin,0. 01% iodine, and some bromine mannite, lipsticks with shimmering effects were initially made using a pearlescent substance found in fish scales. Six thousand year old relics of the hollowed out tombs of the Ancient Egyptian pharaohs are discovered, according to one source, early major developments include, Kohl used by ancient Egypt as a protective of the eye kohl Castor oil used by ancient Egypt as a protective balm. Skin creams made of beeswax, olive oil, and rose water, vaseline and lanolin in the nineteenth century. The Ancient Greeks also used cosmetics as the Ancient Romans did, Cosmetics are mentioned in the Old Testament, such as in 2 Kings 9,30, where Jezebel painted her eyelids—approximately 840 BC—and in the book of Esther, where beauty treatments are described. One of the most popular traditional Chinese medicines is the fungus Tremella fuciformis, used as a beauty product by women in China, the fungus reportedly increases moisture retention in the skin and prevents senile degradation of micro-blood vessels in the skin, reducing wrinkles and smoothing fine lines. Cosmetic use was frowned upon at many points in Western history, for example, in the 19th century, Queen Victoria publicly declared make-up improper, vulgar, and acceptable only for use by actors. During the sixteenth century, the attributes of the women who used make-up created a demand for the product among the upper class. As of 2016, the worlds largest cosmetics company is LOréal, the market was developed in the US during the 1910s by Elizabeth Arden, Helena Rubinstein, and Max Factor. These firms were joined by Revlon just before World War II, during the 18th century, there was a high number of incidences of lead-poisoning because of the fashion for red and white lead makeup and powder. This led to swelling and inflammation of the eyes, attacked tooth enamel, heavy use was known to lead to death. Concealer is commonly used by men, Cosmetics brands release products especially tailored for men, and men are increasingly using them. Cosmetics are intended to be applied externally, a subset of cosmetics is called make-up, refers primarily to products containing color pigments that are intended to alter the users appearance
2.
Skin
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Skin is the soft outer tissue covering vertebrates. Other animal coverings, such as the arthropod exoskeleton have different developmental origin, structure, the adjective cutaneous means of the skin. In mammals, the skin is an organ of the system made up of multiple layers of ectodermal tissue. Skin of a different nature exists in amphibians, reptiles, all mammals have some hair on their skin, even marine mammals like whales, dolphins, and porpoises which appear to be hairless. The skin interfaces with the environment and is the first line of defense from external factors, for example, the skin plays a key role in protecting the body against pathogens and excessive water loss. Its other functions are insulation, temperature regulation, sensation, severely damaged skin may heal by forming scar tissue. This is sometimes discoloured and depigmented, the thickness of skin also varies from location to location on an organism. The skin on the palms and the soles of the feet is 4 mm thick, the speed and quality of wound healing in skin is promoted by the reception of estrogen. Primarily, fur augments the insulation the skin provides but can serve as a secondary sexual characteristic or as camouflage. On some animals, the skin is hard and thick. Reptiles and fish have hard scales on their skin for protection. Amphibian skin is not a barrier, especially regarding the passage of chemicals via skin and is often subject to osmosis. For example, a sitting in an anesthetic solution would be sedated quickly. Amphibian skin plays key roles in everyday survival and their ability to exploit a range of habitats. Keratinocytes are the cells, constituting 95% of the epidermis, while Merkel cells, melanocytes. Keratinocytes from the stratum corneum are eventually shed from the surface, the epidermis contains no blood vessels, and cells in the deepest layers are nourished by diffusion from blood capillaries extending to the upper layers of the dermis. The epidermis and dermis are separated by a sheet of fibers called the basement membrane. The dermis is the layer of skin beneath the epidermis consists of connective tissue and cushions the body from stress
3.
Innate immune system
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The cells of the innate system recognize and respond to pathogens in a generic way, but, unlike the adaptive immune system, the system does not provide long-lasting immunity to the host. Innate immune systems provide immediate defense against infection, and are found in all classes of plant, the innate immune system is an evolutionarily older defense strategy, and is the dominant immune system found in plants, fungi, insects, and primitive multicellular organisms. Anatomical barriers include physical, chemical and biological barriers, the epithelial surfaces form a physical barrier that is impermeable to most infectious agents, acting as the first line of defense against invading organisms. Desquamation of skin also helps remove bacteria and other infectious agents that have adhered to the epithelial surfaces. Lack of blood vessels and inability of the epidermis to retain moisture, in the gastrointestinal and respiratory tract, movement due to peristalsis or cilia, respectively, helps remove infectious agents. The gut flora can prevent the colonization of pathogenic bacteria by secreting toxic substances or by competing with pathogenic bacteria for nutrients or attachment to cell surfaces, the flushing action of tears and saliva helps prevent infection of the eyes and mouth. Inflammation is one of the first responses of the system to infection or irritation. The process of inflammation is initiated by cells already present in all tissues, mainly resident macrophages, dendritic cells, histiocytes, Kupffer cells. At the onset of an infection, burn, or other injuries, chemical factors produced during inflammation sensitize pain receptors, cause local vasodilation of the blood vessels, and attract phagocytes, especially neutrophils. Neutrophils then trigger other parts of the system by releasing factors that summon additional leukocytes and lymphocytes. Cytokines produced by macrophages and other cells of the immune system mediate the inflammatory response. These cytokines include TNF, HMGB1, and IL-1, the complement system is a biochemical cascade of the immune system that helps, or “complements”, the ability of antibodies to clear pathogens or mark them for destruction by other cells. The cascade is composed of plasma proteins, synthesized in the liver. Elements of the complement cascade can be found in many species including plants, birds, fish. All white blood cells are known as leukocytes, leukocytes are able to move freely and interact with and capture cellular debris, foreign particles, and invading microorganisms. Unlike many other cells in the body, most innate immune leukocytes cannot divide or reproduce on their own, mast cells are a type of innate immune cell that reside in connective tissue and in the mucous membranes. They are intimately associated with healing and defense against pathogens. When activated, mast cells rapidly release characteristic granules, rich in histamine and heparin, along with various hormonal mediators and chemokines, histamine dilates blood vessels, causing the characteristic signs of inflammation, and recruits neutrophils and macrophages
4.
Lipid bilayer
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The lipid bilayer is a thin polar membrane made of two layers of lipid molecules. These membranes are flat sheets that form a barrier around all cells. The cell membranes of almost all living organisms and many viruses are made of a bilayer, as are the membranes surrounding the cell nucleus. The lipid bilayer is the barrier that keeps ions, proteins and other molecules where they are needed, Lipid bilayers are ideally suited to this role because, even though they are only a few nanometers in width, they are impermeable to most water-soluble molecules. Bilayers are particularly impermeable to ions, which allows cells to regulate salt concentrations, biological bilayers are usually composed of amphiphilic phospholipids that have a hydrophilic phosphate head and a hydrophobic tail consisting of two fatty acid chains. Phospholipids with certain groups can alter the surface chemistry of a bilayer and can, for example. Just like the heads, the tails of lipids can also affect membrane properties, the packing of lipids within the bilayer also affects its mechanical properties, including its resistance to stretching and bending. Many of these properties have been studied with the use of model bilayers produced in a lab. Vesicles made by model bilayers have also used clinically to deliver drugs. Biological membranes typically include several types of other than phospholipids. A particularly important example in animal cells is cholesterol, which strengthen the bilayer. Cholesterol also helps regulate the activity of certain integral membrane proteins, integral membrane proteins function when incorporated into a lipid bilayer, and they are held tightly to lipid bilayer with the help of an annular lipid shell. Because bilayers define the boundaries of the cell and its compartments, certain kinds of membrane proteins are involved in the process of fusing two bilayers together. This fusion allows the joining of two structures as in the fertilization of an egg by sperm or the entry of a virus into a cell. Because lipid bilayers are quite fragile and invisible in a traditional microscope, experiments on bilayers often require advanced techniques like electron microscopy and atomic force microscopy. When phospholipids are exposed to water, they self-assemble into a sheet with the hydrophobic tails pointing toward the center of the sheet. This arrangement results in two “leaflets” that are each a single molecular layer, the center of this bilayer contains almost no water and excludes molecules like sugars or salts that dissolve in water. The assembly process is driven by interactions between hydrophobic molecules, an increase in interactions between hydrophobic molecules allows water molecules to bond more freely with each other, increasing the entropy of the system
5.
Stratum corneum
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The stratum corneum is the outermost layer of the epidermis, consisting of dead cells. This layer is composed of 15–20 layers of flattened cells with no nuclei and these corneocytes are embedded in a lipid matrix composed of ceramides, cholesterol, and fatty acids. The stratum corneum functions to form a barrier to protect underlying tissue from infection, dehydration, chemicals, desquamation, the process of cell shedding from the surface of the stratum corneum, balances proliferating keratinocytes that form in the stratum basale. These cells migrate through the epidermis towards the surface in a journey takes approximately fourteen days. This complex surrounds cells in the stratum corneum and contributes to the barrier function. Corneodesmosomes facilitate cellular adhesion by linking adjacent cells within this epidermal layer and these complexes are degraded by proteases, eventually permitting cells to be shed at the surface. Desquamation and formation of the envelope are both required for the maintenance of skin homeostasis. A failure to regulate these processes leads to the development of skin disorders. Cells of the stratum corneum contain a network of keratin. These cells can absorb water, further aiding in hydration. In addition, this layer is responsible for the back or stretchy properties of skin. A weak glutenous protein bond pulls the back to its natural shape. The thickness of the stratum corneum varies throughout the body, the mechanical stress of heavy structural strain causes this SL phase in these regions which require additional protection in order to grasp objects, resist abrasion or impact, and avoid injury. In general, the stratum corneum contains 15 to 20 layers of dead cells, the stratum corneum has a thickness between 10 and 40 μm. In reptiles, the stratum corneum is permanent, and is replaced only during times of rapid growth and this is conferred by the presence of beta-keratin, which provides a much more rigid skin layer. In the human forearm, about 1300 cells per cm2 per hour are shed, stratum corneum protects the internal structures of the body from external injury and bacterial invasion. An inability to maintain the skin barrier function due to the dysregulation of epidermal components can lead to skin disorders. For example, a failure to modulate the activity of kallikreins via the disruption of the protease inhibitor LEKTI causes the debilitating disorder Netherton syndrome
6.
Petroleum jelly
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Its folkloric medicinal value as a cure-all has since been limited by better scientific understanding of appropriate and inappropriate uses. It is recognized by the U. S. Food and Drug Administration as an approved over-the-counter skin protectant, the raw material for petroleum jelly was discovered in 1859 in Titusville, Pennsylvania, United States, on some of the countrys first oil rigs. Workers disliked the material forming on rigs because it caused them to malfunction. Chesebrough took the unrefined black rod wax, as the drillers called it, back to his laboratory to refine it, chesebrough discovered that by distilling the lighter, thinner oil products from the rod wax, he could create a light-colored gel. Chesebrough patented the process of making petroleum jelly by U. S, the process involved vacuum distillation of the crude material followed by filtration of the still residue through bone char. He opened his first factory in 1870 in Brooklyn using the name Vaseline, Petroleum jelly is a mixture of hydrocarbons, having a melting point usually within a few degrees of human body temperature, approximately 37 °C. It is flammable only when heated to liquid, then the fumes will light, not the liquid itself, so a wick material like leaves, bark and it is colorless, or of a pale yellow color, translucent, and devoid of taste and smell when pure. It does not oxidize on exposure to the air and is not readily acted on by chemical reagents and it is soluble in dichloromethane, chloroform, benzene, diethyl ether, carbon disulfide and oil of turpentine. Depending on the application of petroleum jelly, it may be USP. This pertains to the processing and handling of the petroleum jelly so it is suitable for medicinal and personal care applications, because they feel similar when applied to human skin, there is a common misconception that petroleum jelly and glycerol are physically similar. Petroleum jelly is a hydrophobic hydrocarbon and insoluble in water. Glycerol is an alcohol that is hydrophilic, by continuously absorbing moisture from the air. This feeling of wetness is similar to the feeling of greasiness produced by petroleum jelly, most uses of petroleum jelly exploit its lubricating and coating properties. Vaseline brand First Aid Petroleum Jelly, or carbolated petroleum jelly containing phenol to give the jelly additional antibacterial effect, has been discontinued. During World War II, a variety of jelly called red veterinary petrolatum. Acting as a sunscreen, it provides protection against ultraviolet rays, the American Academy of Dermatology recommends keeping skin injuries moist with petroleum jelly to reduce scarring. A verified medicinal use is to protect and prevent moisture loss of the skin of a patient in the initial period following laser skin resurfacing. However, petroleum jelly is used extensively by otolaryngologists—ear, nose, and throat surgeons—for nasal moisture and epistaxis treatment, large studies have assessed petroleum jelly applied to the nose for short durations to have no significant side effects
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