Sunburn

Sunburn is an inflammatory skin reaction that follows excessive exposure to ultraviolet radiation-uvr. Uvr exposure can come out of a variety of sources, including tanning beds, phototherapy lamps, solar and electric arc lamps. Sunburn is a burn classified as grade I.
Signs and symptoms of sunburn usually appear within hours after sun exposure and include pain, redness and occasional appearance flictenelor (basic cash). Because exposure often affects large portions of the skin, and sunburn can cause headache, fever and fatigue.
Uncomplicated sunburn is associated with lower short-term morbidity. Most cases resolve spontaneously without significant sequelae. In rare cases, heartburn can be so severe and diffuse inciting cause second degree burns, dehydration or secondary infection. Morbidity and mortality associated with long-term exposure is the development of primary cutaneous neoplasms, including basal cell carcinoma, squamous cell carcinoma and malignant melanoma.
Since the 1920s a tanned skin was a symbol of health and wellness, often indicating the possibility of traveling in sunny areas. Recreational activities in the environment led to increased sun exposure and thus the risk of burns. Bronze skin is a response to damage caused by ultraviolet rays, a tan is definitely not possible.Using artificial solar bronze is common practice, especially for women, but artificial tan is associated with the same risk as exposure to sunlight. In the last 10 years the idea that a nice tan is healthy has lost value because it is closely associated with skin cancer, immunosuppression, and fotoimbatrinirea cataract formation. Severe sunburn with blistering especially during childhood increases the risk individuals to develop cutaneous melanoma.
The clinical presentation may include fever, malaise, nausea, erythema that resolves in 4-7 days, usually by removing layers of skin burn, blistering. , Local warmth, swelling, tenderness, local pain.Most burns are painful, even if not life threatening and treatment is symptomatic. Nonsteroidal anti-inflammatory agents antiprostaglandinice effects and are useful to relieve pain and inflammation, especially if taken from the beginning. Dressings drinks with water or aluminum acetate relieves the pain temporarily. Reinlocuirea fluid is recommended or severe erythema concomitant loss of fluids.
If you have suffered a sunburn:
• Take a bath or a cold shower.• Apply lotion with aloe vera skin several times a day.• Do not break flictenele to avoid infection and to speed healing of burns.• If appropriate, take a painkiller such as aspirin, ibuprofen (Advil) or acetaminophen. Never give aspirin to children and teenagers, because it can cause a rare but extremely dangerous (Reye syndrome).


Consult your doctor if the sunburn lead to complications such as rash, itching or fever.
PathogenesisSunburn is a delayed inflammatory response caused by excessive exposure to ultraviolet radiation, particularly ultraviolet radiation type B rays include 5% of the total energy reaching the earth surface. It is composed of ultraviolet A, B and C rays A are divided into UV-A I and UV-A II. Sunlight contains the entire spectrum of ultraviolet rays A and B but only touch the earth. Approximately 98% of solar ultraviolet radiation at the surface of the earth is represented by the rays can penetrate glass A. Ray, not B rays.
A Girl's rays, all rays C and 90% of the B are filtered by the ozone layer so the rays do not reach C and the B only place on earth 10%. Exposure to C rays can result from exposure to electric arcs, bactericidal lamps and mercury lamps. UV penetration depth into the skin depends on the wavelength, the longer this is how the penetration is so deep. Approximately 90% of B rays are absorbed by the epidermis, while 50% of the rays to reach the basal layer or adipose tissue.Ozone layer thickness varies with the seasons. It is thicker in the winter and summer thin. Decreased ozone pollution. Components active nitrogen, the halogen and hydrogen compounds can destroy ozone, nitrogen comes from many sources (supersonic aircraft, air pollution, fertilizers, micro-organisms used in refrigerators and aerosols clorofluorocarbonii, solvents and halogens with bromine that are used to extinguish fire contribute to ozone depletion.
Formation of carbon dioxide keeps heat near the earth surface, cools the stratosphere and increase ozone loss. A drop of 1% of ozone causes an increase by 1-2% B rays and a secondary increase of 2% of skin cancers. UV exposure increases 4% for every 300 m in altitude, covering sand, pavement, snow and water. Burn solarre succebilitatea humidity decreases. The equator receives the greatest amount of ultraviolet during the year.
Measurement of sunburn and skin protectionSunburn measurement unit is defined as the minimum erythema dose of ultraviolet B minimal exposure needed to produce erythema clear borders that followed the introduction of a single exposures. Solar screens are numbered with a protection factor, SPF sunscreen printrun first number that reflect protection against ultraviolet B. There are no standard measurements for the A. SPF numbers are calculated by dividing the minimal erythema dose to the sunscreen without screen.
Molecular effects of UV on the skin
UV-B radiation causes most sunburn and is 1000 times the A. eritmogena against UV-B induces DNA alterations. UV-A cause 15% burns but fotetoxice reactions to drugs cause the most severe. UV-A and UV-B are absorbed by the chromophore that resonates in the same ultraviolet wavelength and become excited as the gradient. Cromoforii with wavelengths below 300 nm are nucleic acids and amino acids, urocanic. Melanin is the chromophore with a wavelength greater.
DNA from epidermal keratinocytes absorb ultraviolet forcing formation of pyrimidine dimers. Cells with altered DNA can repair DNA or can be removed by the formation of apoptotic keratinocytes and the activation of the p53 gene. Ultraviolet radiation increases synthesis and release of arachidonic acid metabolites: prostaglandin E2, PG-D2, PG-F2, cytokines: IL-1, IL-6, IL-8, IL-10, IL-12, tumor necrosis factor molecule adhesion, histamine, kinine, nitric oxide. Ractive oxygen species can induce membrane lipid peroxidation and destruction. Alcohol consumption is associated with an increased area of burns, high initial pain and develop blisters.
Cellular effects of ultraviolet light on skin
Exposure to sunlight has beneficial effects of stimulating the cutaneous synthesis of vitamin D and body heat. Unfortunately, when the skin is subject to excessive exposure to ultraviolet radiation from the negative effects may occur. The most common effect is acute sunburn or solar erythema.
Originally forcing ultraviolet erythema skin vessels cause vasodilation characteristic. The release of cytokines contribute to an inflammatory reaction leading to infiltration with neutrophils and T lymphocytes 2 hours after exposure is observed lesions on the skin. Epidermal keratinocytes and Langerhans cells undergo changes as a consequence of apoptotic DNA alteration. Redness occurs 3-4 hours after exposure to high levels at 24 hours.
A less intense exposure or short-term increases skin pigmentation known as tanning, which allows to protect skin from further exposure. Increased skin pigmentation occurs in two phases, the first and the second is immediate pigmentation is late bronze. Immediate pigmentation occurs during sun exposure and arise by altering existing melanin (oxidation redistribution). It can disappear quickly or persist for several days. Result from the late Bronze epidermal melanin synthesis and requires a longer period of time to become visible-24-72 hours. Through repeated exposure to ultraviolet thicken skin by epidermal hyperplasia with thickening of the stratum corneum. Lead exposure and immune suppression contributed to the occurrence of skin cancers or melanomas nonmelanoame and infections.