Malo opaka utoto (mabedi a dzuwa) amatulutsa kuwala kwa ultraviolet (UV), makamaka mu mawonekedwe a UVA (315–400 nm), komanso pang'ono UVB (280–315 nm). Ngakhale kuti kuwala kwa dzuwa kwachilengedwe kumakhala ndi mitundu yonse iwiri ya kuwala, zida zopaka utoto nthawi zambiri zimatulutsa kuwala kwa UVA, komwe kumatha kukhala ndi zotsatira zosiyana pakhungu komanso thanzi lonse. Nkhaniyi ikuwunika momwe matenda ndi khungu zimakhudzira kuwala kwa UVA ndi UVB kuchokera ku malo opaka utoto.
1. UVA ndi UVB: Kusiyana Kwakukulu
| Khalidwe | UVA (Mafunde Aatali) | UVB (Short-wave) |
|---|---|---|
| Kuzama kwa Kulowa | Kuzama (dermis) | Zakunja (epidermis) |
| Zotsatira za Kupaka Khungu | Chomwe chimayambitsa okosijeni (chomwe chimayambitsa okosijeni) | Kuchedwa (kuyambitsa melanin) |
| Kupanga Vitamini D | Zochepa mpaka palibe | Gwero lalikulu |
| Njira Yowonongera DNA | Zosalunjika (kupanga ma ROS) | Molunjika (thymine dimers) |
| Kudwala khansa | Kugwirizana ndi melanoma | Kugwirizana ndi squamous cell carcinoma (SCC) |
| Kupondereza chitetezo chamthupi | Wamphamvu (wadongosolo) | Pakati (pamalo amodzi) |
2. Zotsatira za UVA pazachipatala m'makina opaka utoto
A. Kukalamba kwa khungu (kujambula zithunzi):
UVA imalowa mkati mwa dermis, ndikuswa collagen ndi elastin kudzera mu reactive oxygen species (ROS).
Izi zimapangitsa kuti khungu lizioneka ngati makwinya, khungu looneka ngati chikopa komanso kukalamba msanga kwa dzuwa.
B. Kuletsa Chitetezo cha Mthupi:
UVA imasintha ntchito ya maselo a Langerhans, motero imachepetsa chitetezo cha mthupi pakhungu.
Izi zimawonjezera chiopsezo cha matenda a pakhungu (monga HPV ndi herpes) ndipo zitha kufooketsa mayankho a katemera.
C. Kuopsa kwa Melanoma
UVA imayambitsa kuwonongeka kwa DNA ya okosijeni, zomwe zimapangitsa kuti pakhale khansa ya khansa ya pakhungu yoopsa kwambiri (melanoma).
Kafukufuku akusonyeza kuti anthu omwe amagwiritsa ntchito mipanda yopaka utoto ali ndi chiopsezo chachikulu cha 59% chotenga khansa ya melanoma (JAMA Dermatology, 2014).
D. Palibe vitamini D yokwanira yopangidwa
Mosiyana ndi UVB, UVA siisintha 7-dehydrocholesterol kukhala vitamini D₃, zomwe zikutanthauza kuti malo opaka utoto sagwira ntchito popanga vitamini D.
3. Zotsatira za UVB pazachipatala m'makina opaka utoto
A. Kupsa ndi dzuwa ndi kuwonongeka kwa DNA
UVB imayambitsa kusintha kwa DNA mwachindunji (thymine dimers), zomwe zimawonjezera chiopsezo cha squamous cell carcinoma (SCC) ndi basal cell carcinoma (BCC).
Mabedi opaka utoto okhala ndi UVB amathandizira kuwotcha ndi dzuwa.
B. Kapangidwe ka Vitamini D (kochepa m'malo opaka utoto)
Ngakhale kuti UVB ndi yofunikira popanga vitamini D₃, makina ambiri opaka utoto amachepetsa kukhudzana ndi UVB kuti achepetse chiopsezo cha kupsa, zomwe zimapangitsa kuti zisagwire bwino ntchito pa izi.
C. Kuletsa Chitetezo cha Mthupi Kumalo Omwe Ali
UVB imachepetsa kuchuluka kwa maselo omwe amabwera ndi ma antigen pakhungu, koma imayambitsa kuchepa kwa chitetezo chamthupi kuposa UVA.
Momwe mungathanirane ndi kuwonongeka kwa UV:
Valani magalasi oteteza maso.
Gwiritsani ntchito mafuta oteteza ku dzuwa omwe ali ndi chitetezo cha UVA/UVB.
Sankhani zipangizo zomwe sizimatulutsa kuwala kwambiri.