Effects Of Ultraviolet On The Growth Of Candida Albicans

ObjectiveTo understand the differences of pathogenicity between Candida albicans parentalcontrol strain CAF2by different wave length of ultraviolet radiation，we comparedthe hypha formation rate in these three stains，the pathogenic roles in systemiccandidiasis in murine model．These works may offer theoretical supports forscreening the most sensitive ultraviolet wave band of Candida albicans and exploringeffective，low toxic and broad-spectrum antifungal agent．Methods1、To compare3groups with different doses by ultraviolet irradiation every other dayfor7days, dose of UVA were0.5、1.0、1.5、2.0、3.0J/cm~2，UVB were similar, thecontrol group did not irradiated.2、Induction of hyphal form was conducted for three groups with RPMI1640mediumat37℃for3h and observe hyphae formationin microscope, the Ultraviolet dosage of UVA、UVB and the control group was theformer group which can suppress C.albicans grows.3、Three groups of mice：UVA，UVB and the control group without irradiation wereset up in murine model with systemic candidasis．Colony forming units of C．albicanswere determined in infected kidney and spleen with plating dilution method．Results1、Colonies in UVA group were less than normal compared to the control group andlittle change between different doses,however colonies in UVB group were much less than that without irradiation. As UVB dose increased, colonies decreasedsignificantly.UVA3.0J/cm~2still had colony grow, whereas UVB2.0J/cm~2had nocolony, colonies no longer grow when UVB illuminate with2.0J/cm~2on the platewhich have had colonies.2、Hyphal formation rate were88.50±5.56（no radition）、76.58±6.87（UVA）、22.35±8.90（UVB）.The results between three group have statistical significance．3、The murine model of hematogenously disseminated candidiasis were successfullyestablished，yeast-like colony to grow in incubated pathological tissue．4、CFUs of spleen and kidney organization：CFUs of C.albicans were significantlyhigher in kidney and spleen in the1st，2nd and3rd day after infection in CAF2groupwithout exposed to UV than those in the other two groups：The results between UVAand UVB group have statistical significance．ConclusionsUltraviolet radiation can inhibit the growth of Candida albicans, growth of candiaalbicans were reduced which paralleled with UVB irradiation dosage. Under the samedosage UVB can suppress candia albicans activeness stronger compared to UVA,C.albicans sensitivity to UVB significantly stronger than UVA,,and its developingwas inhibited obviously with irradiation dose over2.0J／cm~2．...