Vitamins are essential nutrients for human metabolism, playing an important role as coenzymes or enzymes in many vital processes for the normal functioning of the body. In recent years, it has become apparent that vitamins are crucial in health and human disease, due to several studies that studied this relationship. Currently, it is known that vitamins can have an important role in the prevention and treatment of cancer, but until now no conclusive results were obtained. In this review, we will present the work and more relevant conclusions obtained in recent years of investigation about the relationship between vitamins and cancer, namely vitamin A, vitamin B complex, vitamin C, vitamin D, vitamin E, and vitamin K.

Although mercury bio-amplifies through the food chain and accumulates in top predators, mercury concentrations in tissues of the wandering albatross are greater than in any other vertebrate, including closely related species. In order to explore the alternative explanations for this pattern, we measured total mercury concentrations in feathers, plasma and blood cells of wandering albatrosses of known age, sex and breeding status sampled at South Georgia. Mercury concentrations were low in feathers and blood components of chicks, and higher in the feathers of young pre-breeders than in feathers or blood of older pre-breeders and breeding adults. There was no effect of sex on mercury concentrations in the feathers of pre-breeders or breeding adults, whereas levels were significantly higher in blood cells of breeding females than males. The high feather mercury concentrations of young pre-breeders compared with older birds suggest an increase in moult frequency as birds approach maturity.

Vitamin C, available in its reduced form (ascorbic acid; AA) and in its oxidized form (dehydroascorbic acid; DHA), may act in physiological conditions as an antioxidant or pro-oxidant. The aim of this study is to evaluate the cytotoxic effects of pharmacological doses of AA in a human colorectal adenocarcinoma cell line (WiDr) in vitro, through spectrophotometry, clonogenic assays and flow cytometry, and in vivo with xenotransplanted Balb/c nu/nu mice. The results show that the reduced form of vitamin C induces an anti-proliferative and cytotoxic effect in adenocarcinoma colorectal cells under study. The results obtained in vivo after treatment with AA showed a large reduction in the rate of tumor growth. Such understanding can guide decisions about which colorectal cancer patients might potentially benefit from vitamin C pharmacologic therapy.

23Cephalopod beaks found in the diet of predators have been a major source of 24 scientific information. In this study, we evaluated the usefulness of DNA and 25 contaminants analysis (total mercury-T-Hg) in cephalopod beaks in order to assess their 26 applicability as tools in marine ecology studies. We concluded that, when applying DNA 27 techniques to cephalopod beaks from Antarctic squid species, when using flesh attached 28 to those beaks, it was possible to obtain DNA and to successfully identify cephalopod 29 species; DNA was not found on the beaks themselves. This study also showed that it is 30 possible to obtain information on T-Hg concentrations in beaks: the T-Hg concentrations 31 found in the beaks were 6 to 46 times lower than in the flesh of the same cephalopod 32 species. More research on the relationships of mercury concentrations in cephalopod 33 beaks (and other tissues), intra-and inter-specifically, are needed in the future. 34 35 CAPSULE ABSTRACT: DNA and contaminants analyses for the first time in 36 cephalopods beaks showed that flesh attached to beaks allows DNA species ID and beaks 37 had 6-46 times less total mercury than flesh. 38 39

Polar marine ecosystems have global ecological and economic importance because of their unique biodiversity and their major role in climate processes and commercial fisheries, among others. Portugal and Spain have been highly active in a wide range of disciplines in marine biology of the Antarctic and the Arctic. The main aim of this paper is to provide a synopsis of some of the results and initiatives undertaken by Portuguese and Spanish polar teams within the field of marine sciences, particularly on benthic and pelagic biodiversity (species diversity and abundance, including microbial, molecular, physiological and chemical mechanisms Journal of Sea Research 83 (2013) 9-29 ☆ Given his role as Guest Editor, Joao-Carlos Marques had no involvement in the peer-review of this article and has no access to information regarding its peer-review. Full responsibility for the editorial process for this article was delegated to Angel Borja.⁎