Histone modifications impact various processes. In examining histone acetyltranferase HAT3 of Leishmania donovani, we find elimination of HAT3 causes decreased cell viability due to defects in histone deposition, and aberrant cell cycle progression pattern. HAT3 associates with proliferating cell nuclear antigen (PCNA), helping load PCNA onto chromatin in proliferating cells. HAT3-nulls show he...

1. The effect of the nutritional state of Didinium nasutum on its resistance to short ultraviolet (UV) radiation (2654 A) and its recovery from the injury following illumination with visible light (4350 A, blue) was studied. 2. The resistance of a didinium to UV is considerably increased by feeding it a paramecium 15 to 60 minutes before exposure to UV. If fed just before exposure to UV, the re...

Pterygium is a chronic eye disease: among its recognized risk factors there is long-term exposure to ultraviolet (UV) radiation. The Sun is the main source of UV exposure: according to the World Health Organization, the Population Attributable Fraction of pterygium due to solar radiation (SR) is 42-74%. Outdoor work can deeply influence the eye exposure to solar UV rays, but, despite this, pter...

OBJECTIVE Solar ultraviolet (UV) radiation is an important environmental factor that affects human health. The understanding of diurnal variations of UV radiation at anatomical sites may be helpful in developing ways to protect humans from the harmful effects of UV radiation. METHODS In order to characterize the diurnal variations, the UV exposure values were measured at 30 min intervals by u...

UV-B radiation induced alterations in the contents of photosynthetic pigments, antioxidants (phenolics and ascorbic acid) and chlorophyll fluorescence in two tropical variants of Trichosanthes cucumerina L. – Cucurbitaceae. The Green (Variant A) and Light Green (Variant B) variants of T. cucumerina, which had earlier been shown to differ in their total phenolics contents, were used for the stud...

Ultraviolet-B (UV-B) photons can cause substantial cellular damage in biomolecules, as is well established for DNA. Because RNA has the same absorption spectrum for UV as DNA, we have investigated damage to this cellular constituent. In maize (Zea mays) leaves, UV-B radiation damages ribosomes by crosslinking cytosolic ribosomal proteins S14, L23a, and L32, and chloroplast ribosomal protein L29...

Exposure to ultraviolet (UV) light can cause significant damage to mammalian cells and, although the spectrum of damage produced varies with the wavelength of UV, all parts of the UV spectrum are recognised as being detrimental to human health. Characterising the cellular response to different wavelengths of UV therefore remains an important aim so that risks and their moderation can be evaluat...

This paper presents a UV (ultraviolet) lithography apparatus that utilizes an array composed of UV-LED (light emitting diode) collimation modules as a micro-patterning light source for PCB (printed circuit board) fabrication. To provide a uniform (non-uniformity > 90%) and collimated (FWHM < ±2°) exposure area, hexagonal light source modules are disposed in a hexagonal array. Each module is con...

In this study, morphological and physiological effects of the stress with the UV-C rays on the industrial Atlanta type beans (Phaseolus vulgaris L. Cv, Atlanta) were analyzed. The plants were raised in an automated green house with the ecological conditions. The plants were grown in the green house with UV-C lamb (250) for 6, 8, 10, 12 and 14 days. After which their root lengths and seeding hei...

Downstream of Ras, the serine/threonine kinase, B-raf, has recently been reported to be mutated, among other carcinomas, in a substantial subset of primary melanomas with a preponderance of the oncogenic V599E transition. As the risk of melanoma is enhanced by intermittent ultraviolet (UV) exposure but is less with chronic UV exposure, we here studied B-raf kinase domain (exon 15) mutations in ...