Matende ezuva anoburitsa mwaranzi ye ultraviolet (UV), kunyanya muchimiro cheUVA (315–400 nm), uye zvishoma UVB (280–315 nm). Kunyange zvazvo chiedza chezuva chechisikigo chine huwandu hwakaringana hwemarudzi ese ari maviri emwaranzi, michina yezuva inowanzoburitsa mwero wakakwira weUVA, izvo zvinogona kuva nemigumisiro yakasiyana paganda nehutano hwese. Chinyorwa chino chinoongorora mhedzisiro yekurapa uye yeganda yekusvibiswa kweUVA neUVB kubva kumatende ezuva.
1. UVA vs. UVB: Musiyano Mukuru
| Hunhu | UVA (Mafungu marefu) | UVB (Short-wave) |
|---|---|---|
| Kudzika kwekupinda | Dema (dermis) | Pamusoro (epidermis) |
| Mhedzisiro yeKutsvuka Kweganda | Pakarepo (inooxidative) | Kunonoka (kunomutsa melanin) |
| Kugadzirwa kweVhitamini D | Zvishoma kusvika hapana | Chitubu chikuru |
| Maitiro Ekukuvadzwa kweDNA | Kusajeka (kuumbwa kweROS) | Yakananga (thymine dimers) |
| Kurwara nekenza | Yakabatana ne melanoma | Zvinobatanidzwa ne squamous cell carcinoma (SCC) |
| Kudzvinyirirwa kweMadziviriro Emuviri | Yakasimba (yakarongeka) | Zviri pakati nepakati (zviri munzvimbo imwe chete) |
2. Mhedzisiro yeUVA mukurapa mumichina yekuchenesa ganda
A. Kukwegura kweganda (photoaging):
UVA inopinda mukati meganda, ichipwanya collagen ne elastin kuburikidza ne reactive oxygen species (ROS).
Izvi zvinokonzeresa makwinya, ganda rakaita sedehwe uye kuchembera kwenguva pfupi (solar elastosis).
B. Kudzvinyirirwa kweMadziviriro Emuviri:
UVA inochinja mashandiro emasero eLangerhans, nokudaro ichideredza dziviriro yeganda.
Izvi zvinowedzera mukana wekubatwa nezvirwere zveganda (semuenzaniso HPV neherpes) uye zvinogona kuderedza simba remajekiseni.
C. Njodzi yeMelanoma
UVA inokonzera kukuvara kweDNA, izvo zvinokonzera melanoma (rudzi rwekenza yeganda runouraya zvakanyanya).
Ongororo dzinoratidza kuti vanhu vanoshandisa mibhedha yeganda vane mukana wepamusoro we59% wekuva ne melanoma (JAMA Dermatology, 2014).
D. Hapana kugadzirwa kwakakosha kwevhitamini D
Kusiyana neUVB, UVA haishandure 7-dehydrocholesterol kuita vhitamini D₃, zvichireva kuti nzvimbo dzekuisa ganda paganda hadzina simba pakugadzira vhitamini D.
3. Mhedzisiro yeUVB mukurapa mumichina yekuchenesa
A. Kupiswa nezuva uye kukuvara kweDNA
UVB inokonzera kuchinja kweDNA zvakananga (thymine dimers), izvo zvinowedzera njodzi ye squamous cell carcinoma (SCC) uye basal cell carcinoma (BCC).
Mibhedha yekuchenesa ganda ine UVB inowedzera kupiswa nezuva (erythema).
B. Kugadzirwa kweVitamin D (kunongogumira muminda yekutsvukisa ganda)
Kunyange zvazvo UVB ichikosha pakugadzira vhitamini D₃, michina mizhinji yekutsvukisa ganda inoderedza kusviba kweUVB kuderedza njodzi yekutsva, izvo zvinoita kuti isashande zvakanaka pachinangwa ichi.
C. Kudzvinyirirwa kweMadziviriro Emuviri Munzvimbo Imwe Chete
UVB inoderedza huwandu hwemasero anouya neantigen paganda, asi inokonzera kudzvinyirirwa kwemuviri zvishoma pane UVA.
Maitiro ekugadzirisa kukuvara kweUV:
Pfeka magirazi ekudzivirira.
Shandisa mafuta ekudzivirira zuva ane dziviriro yeUVA/UVB.
Sarudza michina ine mwaranzi shoma.