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| Afonso,S.G.; Enríquez de Salamanca,R.; Batlle,A.M. del C.. |
| Porphyrias are a family of inherited diseases, each associated with a partial defect in one of the enzymes of the heme biosynthetic pathway. In six of the eight porphyrias described, the main clinical manifestation is skin photosensitivity brought about by the action of light on porphyrins, which are deposited in the upper epidermal layer of the skin. Porphyrins absorb light energy intensively in the UV region, and to a lesser extent in the long visible bands, resulting in transitions to excited electronic states. The excited porphyrin may react directly with biological structures (type I reactions) or with molecular oxygen, generating excited singlet oxygen (type II reactions). Besides this well-known photodynamic action of porphyrins, a novel... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Photodynamic; Porphyrias; Porphyrins; Protein alterations. |
| Ano: 1999 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1999000300002 |
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| Maeda, Hajime; Akematsu, Takahiko; Fukui, Risa; Matsuoka, Tatsuomi. |
| The resting cysts of Colpoda cucullus were resistant to not only drying, but high and low temperatures. The critical temperatures for the survival of wet cysts ranged from 40 oC (3-hr exposure) to 45 oC (10-min exposure), and those of the dried cysts ranged from 80 oC (3-hr exposure) to 100 oC (30-min exposure). Frozen (-30 oC, 3 hr) and remelted wet cysts also survived. Ca2+-induced resting cysts excysted when the external Ca2+ was removed. However, the excystment-inducing effect by Ca2+ removal was canceled by the addition of cations such as Na+, K+, and Mg2+ in the surrounding medium. When the mature cysts transformed in a diluted buffer without any other salts were temporally exposed to Ca2+ and subsequently resuspended in the buffer without Ca2+,... |
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Palavras-chave: Colpoda; Encystment; Excystment; Resistance to temperature; Ca2+; Porphyrins. |
| Ano: 2005 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/146 |
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