Ultraviolet-B light

Wang ZY, Huang M, Lou Y, Xie J, Reuhl K, Newmark H, Ho C, Yang C and Conney A. 1994. Inhibitory effects of black tea, green tea, decaffeinated black tea, and decaffeinated green tea on ultraviolet B light-induced skin carcinogenesis in 7,12-dimethylbenz[<3]anthracene-initiated SKH-1 mice. Cancer Res 54(13) 3428-3435. 

Yakimchuk, R. and Hoddinott, J., The influence of ultraviolet-B light and carbon dioxide enrichment on the growth and physiology of seedlings of three conifer species. Can. J. For. Res., 24, 1, 1994. 

Amstad P, Hussain SP, Cerutti P. 1994. Ultraviolet B light-induced mutagenesis of p53 hotspot codons 248 and 249 in human skin fibroblasts. Mol Carcinog 10 181-188. 

Ultraviolet B light is effective in guttate psoriasis and potentiates the effects of topical agents such as calcipotriol and dithranol. A psoralen followed by ultraviolet light (PUVA) is used in severe cases (see Psoralens, p. 306). 

UTO UTZ UUN uv UVA UVB UVC UVJ UVL UVR UWF UWM upper tibial osteotomy ultrasound urine urea nitrogen ultraviolet ultraviolet A light ureterovesical angle ultraviolet B light umbilical vein catheter ureterovesical junction ultraviolet light ultraviolet rays unknown white female unknown white male... 

Sakamoto, A., Lan, V. T. T., Hase, Y, Shikazono, N., Matsunaga, T., and Tanaka, A. (2003). Disruption of the AtREV3 gene causes hypersensitivity to ultraviolet B light and 7-rays in Arabidopsis. Implications of the presence of a translesion synthesis mechanism in plants. Plant Cell 15, 2042-2057. 

Ramani S, Jayabaskaran C (2008) Enhanced catharanthine and vindoline production in suspension cultures of Catharanthus roseus by ultraviolet-B light. J Mol Signal 3 9-14. doi 10.1186/1750-2187-3-9... 

Inspect the paper in ultraviolet light—conveniently in front on a Hanovia ultraviolet strip light—in a dark room. The acids show up as intense blue fluorescent spots. Mark with a pencil the positions of all spots. The position of the two spots arising from solution (C) should be compared with the single spots arising from solutions (A) and (B). It is probable that the solution (B) of pure N-methylan-thranilic acid may also reveal a faint spot corresponding to anthranilic acid still present in minute traces in the methylated acid cf. p. 223). 

Coal tar contains numerous hydrocarbon compounds formed from distillation of bituminous coal. Ultraviolet B (UVB) light-activated coal tar photoadducts with epidermal DNA and inhibits DNA synthesis. This normalized epidermal replication rate reduces plaque elevation. 

Stege, H. et al., Enzyme plus light therapy to repair DNA damage in ultraviolet-B-irradiated human skin, Proc. Natl. Acad. Sci. USA 97, 1790-1795, 2000. 

Figure 3. Principles of photochemical modification of polymer (e.g. PTFE) by ultraviolet (UV) light in ammonia or acetylene atmosphere (A-B). Basic processes of photochemical modification of polymer by UV light (hv) in atmosphere are (a) surface reactions, (b) reactions in atmosphere and (c) reactions in polymer. [5].

Persistent photosensitivity developed in eight men after occupational exposure to hot epoxy resin fiimes. The condition was limited to sites contacted by the resin. Small doses of ultraviolet-A light evoked abnormal reactions consisting of erythema, edema, and papules in the clinically involved skin. Positive photopatch tests were observed to epoxy resin in four subjects and to bisphenol A in all subjects. Another study showed that bisphenol A can be released during the thermal decomposition of epoxy resin in the temperature range of 250-350°C. Photosensitizing activity was explained by the formation of ftee radicals during exposure to ultraviolet-B radiation of bisphenol A vapor, to form a semiquinone derivative of bisphenol A ... 

Cholecalciferol (D3) and its active form 1,25-di-hydroxycholecalciferol are only to a certain extend vitamins because they can be synthesized by the human body. However deficiencies resulting in rickets in children and osteomalacia in adults do exist. Cholecalciferol can be synthesized by humans in the skin upon exposure to ultraviolet-B (UVB) radiation from sunlight, or it can be obtained from the diet. Plants synthesize ergosterol, which is converted to vitamin D2 (ergocalciferol) by ultraviolet light. Vitamin D2 may be less active in humans. Vitamin D promotes uptake of calcium and phosphate in the intestine and it stimulates osteoclasts to break down hydroxyapatite and release calcium into blood. Vitamin D is discussed in more detail in Chapter 24, Section V.a. 

Acitretin is most useful for the treatment of severe psoriasis, particularly the pustular and erythrodermic variants. Psoriatic nail changes and arthritis also may respond. Combining the drug with ultraviolet light therapy (Re-UVB, in the case of ultraviolet B radiation, or Re-PUVA, with psoralen plus ultraviolet A radiation) permits the use of lower doses of both acitretin and ultraviolet radiation. Other conditions for which the drug may be especially useful include congenital and acquired hyperkeratotic disorders, such as the ichthyoses and palmoplantar keratodermas, and severe lichen planus. 

Booij-James IS, Dube SK, Jansen MAK, Edelman M, Mattoo AK. 2000. Ultraviolet-B radiation impacts light-mediated turnover of the photosystem II reaction center heterodimer in Arabidopsis mutants altered in phenolic metabolism. Plant Physiol 124 1275-1284. 

DeLucia EH, Day TA, Vogelmann TC (1992) Ultraviolet-B and visible light penetration into needles of two species of subalpine conifers during foliar development. Plant Cell Environ 15 921-929... 

Rhodes, L.E., Durham, B.H., Fraser, W.D., and Friedmann, P.S., Dietary fish oil reduces basal and ultraviolet B-generated PGE2 levels in skin and increases the threshold to provocation of polymorphic light eruption, J. Invest. Dermatol., 105, 532, 1995. 

P. M. Rentzepis et al. first demonstrated a bit-oriented 3D optical memory using a photochromic spirobenzopyran shown in Figure 16.3. Isomer A has an absorption band shorter than 450 nm upon irradiation with ultraviolet (UV) light, it converts to isomer B, which has an absorption band around 600 nm, as shown in Figure 16.4. Isomer B gives fluorescence around 700 nm upon photoexcitation with 500-700 nm light. 

A 68-year-old man had a photosensitive drug eruption while taking flutamide (24). The minimal erjhhema dose with ultraviolet A light was reduced to 2 J/cm and recovered to over 16 J/cm after withdrawal, without changing reactivity to ultraviolet B. The absorption spectrum of flutamide was not altered after ultraviolet A irradiation. 

Ultraviolet B (UVB) light (290 to 320 nm) continues to be an important phototherapeutic intervention for psoriasis. 

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