Xia Mi-Na, Wang Xue-Min, Liu Yan-Qun, Yuan Chao, Zou Ying, Fan Guo-Biao
Dermatological Department, Third affiliated hospital of Xuzhou Medical College, Xuzhou, China.
Cutan Ocul Toxicol. 2012 Dec;31(4):306-11. doi: 10.3109/15569527.2012.668599. Epub 2012 Mar 27.
Skin pigmentation and the stratum corneum are the two primary natural factors that protect against UV damage. Although several classification systems exist to quantify the ability of the skin to protect itself from damaging UV radiation, few reports have assessed skin parameters and photoreaction in persons of Han Chinese descent.
To understand the relationship between skin darkness, skin thickness, and photoreaction in Chinese Han subjects.
Thirty-one subjects were exposed to UVA and UVB. Minimal persistent pigment darkening dose (MPPD) and minimal erythema dose (MED) were obtained. Before the UV irradiation, the test sites were measured by the Mexameter MX 16, Chromameter CR400, and Skin B-ultrasonic to determine skin color and thickness>. Using the ratio of J(MPPD)/J(MED), we classified the subjects into four energy skin phototypes (ESPTs) and the skin parameters for each of these groups were analyzed.
Skin color and skin thickness were significantly different among the ESPTs. There was also a significant positive correlation between skin group and the skin color and thickness parameters (b*, melanin index [MI], thickness). As the ESPTs increased from ESPT A to ESPT D, the mean dose to achieve MED increased, while the MPPD decreased.
As the ESPTs increased from type A to type D, there was a proclivity to tan rather than burn. Similarly, the skin became darker and thicker as the phototype increased from A to D.
皮肤色素沉着和角质层是抵御紫外线损伤的两个主要天然因素。尽管存在几种分类系统来量化皮肤自我保护免受紫外线辐射损伤的能力，但很少有报告评估汉族人群的皮肤参数和光反应。
了解中国汉族受试者皮肤颜色深浅、皮肤厚度与光反应之间的关系。
31名受试者接受UVA和UVB照射。获得最小持续色素沉着剂量（MPPD）和最小红斑剂量（MED）。在紫外线照射前，使用Mexameter MX 16、色差仪CR400和皮肤超声仪测量测试部位，以确定皮肤颜色和厚度。利用J（MPPD）/J（MED）的比值，将受试者分为四种能量皮肤光类型（ESPTs），并分析每组的皮肤参数。
ESPTs之间的皮肤颜色和皮肤厚度存在显著差异。皮肤组别与皮肤颜色和厚度参数（b*、黑色素指数[MI]、厚度）之间也存在显著正相关。随着ESPTs从A组增加到D组，达到MED的平均剂量增加，而MPPD降低。
随着ESPTs从A类增加到D类，有倾向于晒黑而不是晒伤。同样，随着光类型从A增加到D，皮肤变得更黑更厚。
