Shanduko Kuchinja Kunokonzerwa Nokudarika Uwandu hweUv
Kujeka kwezuva kunobatsira zvikuru paganda rinogona kuguma nekukwegura kusati kwasvika, kenza yeganda, nemamwe mamiriro ezvinhu akafanana neganda. Kuvhiringidzika kune ultraviolet (UV) chiedza kunoratidzira kusvika 90 muzana yezviratidzo zvose zveganda zvinokuvadza.
Chokwadi Pamusoro Pemazuva Ano UV
Zuva rinobudisa mazai eVV ayo tinopatsanura kuita zvikamu zvichienderana nehuwandu hwehurefu hwahwo (zvichienzaniswa nesanometer, kana nm):
- UVC mihizha (100 kusvika 290 nm)
- UVB radiation (290 kusvika 320 nm)
- Rava radiation (320 kusvika 400 nm)
UVC mizinga yakareba uye yakave yakanyatsopindira nea ozone. Sezvo zvakadaro, hazvibatsiri chaizvo ganda. Zvisinei, mazai eVC anogona kuwanikwa kubva mumhando dzakadai semasikironi emarc arc nemarambi emidzimu.
UVB inobuda mumhepo inobata chikamu chekunze kweganda (epidermis) uye ndicho chinonyanya kukonzera kupisa kwezuva. Inonyanyisa pakati pemaawa 10 am uye 2 masikati kana chiedza chezuva chiri pakuchenesa kwayo. Inonyanya kuwedzera mukati memwedzi yezhizha, kuverenga kwevanenge makumi manomwe kubva muzana yehupenyu hwemunhu hwegore negore. Nemhaka yekudzivirira, UVB haipindi mumirazi nyore nyore.
Mazaiyo eUVA, zvakasiyana, aimbofungidzirwa kuti ane kamuviri kadiki kacho paganda. Zvidzidzo zvekare zvakaratidza kuti UVA ndiyo inonyanya kupa chikamu kukanganisa. UVA inopinda yakadzika mukati meganda nemusimba usina kuchinja zvakanyanya seVB.
Uye, kusiyana neVBB, UVA haisi kushandiswa negirazi.
Migumisiro inokuvadza yeUVA neVBB
Zvose zviviri zvinonzi UVA uye UVB zvinogona kukonzera kukanganiswa kweganda zvakasanganiswa neganda, kusanganisira mibimbi, zvinetso zvekukwegura , kenza yepachirwere, uye utachiona hutachiona hwehutachiona. Kunyange zvazvo tisinganyatsonzwisisi nzira dzekuchinja uku, vamwe vanofunga kuti kuparara kwegogenjini uye nekugadzirwa kwemasimba ehurukuro dzisingabhadhari kunogona kukanganisa DNA kugadzirisa pamatomu.
UV radiation inozivikanwa kuti iwedzere nhamba yemakemikari muzvikamu zvakasununguka zvezuva. Kuwedzerwa kwezuva kuwedzerwa kwezuva kunogonawo kutungamirira kukurudzirwa kwezvipembenene zvinofananidzira zvinonzi actinic keratoses. Actinic keratoses inonzi inofanirwa nokuti imwe muzana ichakura mu squamous cell carcinoma . Actinic keratoses "matambudziko" kazhinji anonzwika nyore kunzwa kupfuura kuona uye achawanzooneka pazviso, nzeve, uye kumashure kwemaoko.
Kuvhenekera kweVV kunogonawo kukonzera seborrheic keratoses , iyo inoita sezvipembenene zvakadai sewart "zvakasimba" paganda. Kusiyana nezvinoitwa actinic keratoses, seborrheic keratoses haisi kuva nekenza.
Collagen Breakdown uye Free Radicals
UV radiation inogona kukonzera collagen kuputsa pazinga rakakwirira kupfuura kukwegura kwakasarudzika . Inoita izvi nokupinda mukati-kati peganda (dermis), zvichiita kuti zvisakanaka zvivako zve elastin. Apo iyi elastin inounganidza, maantimisi anobudiswa izvo zvisingaziviki zvinoputsa collagen uye zvinogadzira izvo zvinonzi "zviya zvezuva." Kuenderera mberi kwekutsvaga kunongomhanya chete nenzira, zvichiita kuti uwedzere kupikisa uye kuputika.
UV rayation ndeyewo wevadzidzisi vehurukuro dzezvemahara . Radicals yakasununguka ndiyo yakasimbiswa mumakemiksijini ane e-electron imwe chete pane maviri.
Nemhaka yokuti electrons inowanikwa muviri, molekoro inofanira kukanda elektrononi yayo isiripo kubva mune mamwe mamolekoro, zvichiita kuti ketani inopindurwa iyo inogona kukuvadza masero ari mu molecular level. Rusununguko rusununguko harusi kungowedzera huwandu hwes enzyme dzinoputsa collagen, dzinogona kushandura sero inowanikwa maitiro nenzira inogona kutungamirira kenza.
Immune System Effects
Mutumbi une simba rekudzivirirwa nemasikirwo ehurumende zvinoreva kurwisa zvirwere uye zvisingawanzogadziriswa masero, kusanganisira kenza. Izvi zvinodzivirira kudzivirirwa kwemasimba zvinosanganisira masero machena eropa anonzi T lymphocytes uye masero eganda anonzi Langerhans masero . Apo ganda rinoratidzirwa kune zuva rakawandisa, mamwe makemikari anosunungurwa anonyatsodzivisa masero aya, kuderedza simba rose rekudzivirira immune.
Iyi haisi iyo nzira bedzi iyo kudhura zvakanyanya kunogona kuderedza chitunha chomunhu. Mutsetse wekupedzisira wemuviri wezvidziviriro zvekudzivirirwa kwezvirwere kune chimwe chinhu chinonzi apoptosis, iyo nzira ye "kuzviuraya masero" inoreva kuuraya masero akaipisisa akave asingakwanisi kuva nekenza. (Ichi ndicho chimwe chezvikonzero nei iwe uchitarisa mushure mekutsvaira kwezuva.) Kunyange zvazvo chirongwa chisina kunyatsonzwisiswa, kuvhara kwevhu rakawanda kunowanzoita kuti kudzivirira apoptosis, zvichibvumira masero akachengetedza mukana wekuva akaipa.
Kuchinja Kweganda Kunokonzerwa neZuva
Kuvhenekera kweVV kunokonzera kusina kukwana uye kuonda kweganda rinonzi solar elastosis, zvichiita kuti kuve nekukakavara kwakanyanya uye kubuda kwezuva. Inogonawo kukonzera masvingo emidziyo yeropa kuti ave akaonda, zvichiita kuti zvive nyore kubvunda uye spider veining (telangiectasias) pachiso.
Pakati pezuva rinonyanya kuzivikanwa zuva-induced pigment mabadiliko ndiwo freckles (solar lentigo). Kushandiswa kunokonzerwa apo ganda re-pigment-rinobudisa masero ( melanocytes ) rakaparadzwa, zvichiita kuti kuwedzerwa kwechirema. Zvikuru zvakakura, zvinowanziwo sezera remakore , zvinowanzoonekwa pamashure emaoko, chifuva, mapepa, maoko, uye kumusoro kumusoro. Kunyange zvazvo mazera ezera anowanzowanikwa kune vakwegura vakuru, havasi ivo vane makore akasiyana-siyana sezvo zita ravo rinoratidza asi chikonzero chezuva kukuvara.
Kuvhenekera kweUV kunogona kutungamirirawo kuonekwa kwemavara machena pamakumbo, maoko, uye maoko sezvinoita maranocytes zvinoparadzwa zvishoma nezvishoma nemirairo yezuva.
Kanzera yeganda uye Melanoma
Kugona kwezuva kukonzera kenza kunonyatsozivikanwa. Iyo mitatu mikuru yekenza yemaperembudzi inonzi melanoma , basal cell carcinoma , uye squamous cell carcinoma.
Melanoma ndiyo inonyanya kuuraya yevatatu sezvo inopararira (metastasizes) nyore nyore kupfuura dzimwe. Basal cell carcinoma ndiyo inowanzoshandiswa uye inotanga kupararira kune imwe nzvimbo pane kugadzirisa mhuka. Squamous cell carcinoma ndiyo yechipiri inowanzozivikanwa uye inozivikanwa kuti inogona kushandiswa, kunyange zvazvo isingazivikanwi seanoranoma.
Zvinotendwa kuti kuwanda kwezuva kubuda kwezuva munhu anogamuchira vasati vava nemakore makumi maviri nemakumi maviri ndiyo inokonzera ngozi ye melanoma. Kusiyana neizvi, njodzi yebasal cell carcinoma kana squamous cell carcinoma inobatanidza zvose zveganda romunhu uye chiyero chehupenyu hwehupenyu hwemazuva ano.
> Sources
- > Ratushny, V .; Gogi, M .; Hick, R .; et al. "Kubvira keratinocyte kusvika kune kenza: pathogenesis uye kuenzanisa kwezvipembenene zvinonzi squamous cell carcinoma." Zvinyorwa zveKliniki Investigation. February 1, 2012; 122 (2): 464-472.
- > Narendhirakannan, R. naHannah, A. "Kushungurudzika Kwepfungwa uye Kanzera Kweganda: Anokurudzira." Ind J Clinic Biochem. April 2013; 28 (2): 110-115.