Pineiro Alvarez B (1983) 2 years personal experience in anapsos treatment of psoriasis in various clinical forms. Medicina cutanea ibero-latino-americana, 11: 65-72. Philips, Neena; Smith, Joan; Keller, Thomas; Gonzalez, Salvador. (2003) Predominant effects of Polypodium leucotomos on membrane integrity, lipid peroxidation, and expression of elastin and matrixmetalloproteinase-1 in ultraviolet radiation exposed fibroblasts, and keratinocytes Journal of Dermatological Science, 32:1-9. Alonso-Lebrero, Jose Luis; Dominguez-Jimenez, Carmen; Tejedor, Reyes; Brieva, Aurora; Pivel, Juan Pablo. (2003) Photoprotective properties of a hydrophilic extract of the fern Polypodium leucotomos on human skin cells. Journal of Photochemistry and Photobiology, B: Biology,70:31-37. Gonzalez S, Alcaraz MV, Cuevas J, Perez M, Jaen P, Alvarez-Mon M, Villarrubia VG. (2,000) An extract of the fern Polypodium leucotomos (Difur) modulates Th1/Th2 cytokines balance in vitro and appears to exhibit anti-angiogenic activities in vivo: pathogenic relationships and therapeutic implications. Anticancer Res. 20:1567-75. Manna SK, Bueso-Ramos C, Alvarado F, Aggarwal BB (2003) Calagualine inhibits nuclear transcription factors-kappaB activated by various inflammatory and tumor promoting agents. Cancer Lett.,20:171-82.