Journal ArticleDOI
Dose-time dependency of tumor formation by chronic UV exposure.
TLDR
It seems as though an animal becomes more resistant to the UV-stimuius as the rate at which the stimulus is presented is increased: an adaptive phenomenon.Abstract:
-An animal experiment is presented which involved a total of 223 albino hairless mice (Skh hr 1). These mice, excluding 24 of them which served as controls, were divided over 6 groups, each of which received a different but constant daily dose of UV radiation from fluorescent sunlamps (Westinghouse FS40TL12). The range of daily doses encompassed a factor of 33. Data on the response of each group as a whole are presented. The group responses are measured in two ways: (1) the proportion of tumor bearing mice (prevalence), and (2) the average number of tumors per survivor (yield). The data provide information on the variation of the group response with time, daily dose and tumor size.
The relationship between the daily dose and the duration of the treatment till 50% of the mice have tumors is given for several sizes of tumors. From these results, and from direct measurements of tumor growth, it appears that the growth of tumors is virtually dose-independent and, in consequence, only the initiation of tumors is dose-dependent. This implies that the theoretical model of UV-tumorigenesis presented by Blum (1959). based on UV-accelerated growth, is incorrect. It is pointed out that, in similarity to chemo- and radiotumorigenesis, the total dose delivered to a mouse for the induction of tumors has to be higher if a high daily dose is used than if a low daily dose is used. It seems as though an animal becomes more resistant to the UV-stimuius as the rate at which the stimulus is presented is increased: an adaptive phenomenon.read more
Citations
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Journal ArticleDOI
In Vivo Fluorescence Spectroscopy and Imaging for Oncological Applications
TL;DR: This poster presents a probabilistic procedure to characterize the response of the immune cells of the central nervous system to laser-spot assisted chemoreception and excites the immune system.
Journal ArticleDOI
Does intermittent sun exposure cause basal cell carcinoma? a case-control study in Western Australia.
TL;DR: Risk of BCC increased substantially with increasing intermittency in poor tanners but not at all in good tanners, and a particular amount of sun exposure delivered in infrequent, probably intense increments will increase risk of BCC more than a similar dose delivered more continuously over the same total period of time.
Journal ArticleDOI
Risk Reduction for Nonmelanoma Skin Cancer With Childhood Sunscreen Use
TL;DR: Using a mathematical model based on epidemiologic data, it is estimated that regular use of a sunscreen with a sun protective factor of 15 during the first 18 years of life would reduce the lifetime incidence of basal and squamous cell carcinomas of the skin by 78%.
Journal ArticleDOI
A new development in UVB phototherapy of psoriasis
TL;DR: A new UVB fluorescent sunlamp, the Philips TL‐01 lamp, which emits a narrow peak around 311–312 nm, with the currently used PhilipsTL‐I2 lamp, is compared in patients with psoriasis.
Book ChapterDOI
Photocarcinogenesis: UVA vs UVB.
TL;DR: The carcinogenicity of UVB radiation is well established experimentally and, to a large extent, understood as a process of direct photochemical damage to DNA from which gene mutations arise as discussed by the authors.
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Journal ArticleDOI
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R. D. Rundel,D. S. Nachtwey +1 more
TL;DR: A new model is presented for the calculation of the increased incidence of non‐melanoma skin cancer in Caucasians resulting from ozone reduction, postulates that the probability of first incidence of such skin cancer is distributed log‐normally as a function of total accumulated lifetime dose of harmful ultraviolet radiation.