Sammanfattning Vitamin E är en substans med antioxidanta egenskaper, ett fettlösligt vitamin som kan finnas i naturliga källor såsom vegetabiliska oljor, ägg, grönsaker, spannmål, frukter,kött men också i syntetisk form. I dagsläget är vitamin E också tillgängligt som kosttillskott och används förebyggande och/eller vid behandling av sjukdomar som kardiovaskulära sjukdomar, arterioskleros, diabetes mellitius samt olika former av cancer. Vid intag av vitamin E kan oxidativ stress minskas vilket produceras av fria radikaler (t.ex. joniserande strålning, giftiga föreningar från luft, vatten, mat) som drabbar celler och på det sättet förebyggs och fördröjs uppkomst av sjukdomar. Utöver sin antioxidant effekt och är vitamin E involverat i immunförsvaret, cellsignalering,genreglering samt andra metaboliska processer. Dessa egenskaper har gjort av vitaminE är en intressant kandidat till utredning vid prostatacancer (adenocarcinom), som är den vanligaste tumörformen i Sverige hos män över 50-års ålder. Denna litteraturstudie har för syfte att undersöka det empiriska stödet för tesen omvitamin E kan ha en förebyggande effekt mot prostatacancer och vilka risker som finns vid intag av vitamin E vid prostatacancer. Tidigare forskning har visat att det har enantioxidativ inverkan på kroppens organ och det har därför funnits en tro på att den kan hjälpa förebygga prostatacancer. Litteraturstudien bygger på originalartiklar framförallt från PubMed, Socialstyrelse hemsidan, WebMd, olika medicinska böcker och i Google med sökord som: vitamin E, prostatacancer, tokoferol och prostatacancer,oxidative stress, antioxidant, androgen metabolism och vitamin E, prostatacancer ocharv, androgen och vitamin E. Resultatet av studierna visar att det inte finns ett entydigt empiriskt stöd för att vitaminE (tokoferol) har en förebyggande effekt mot prostatacancer. Vissa studier visar ett stöd för att det finns en förebyggande effekt, andra visar att det inte finns ett stöd och en visar en signifikant ökad risk för prostatacancer vid intag av tokoferol. Prostatacancer kan inte förebyggas med vitamin E (tokoferol) enligt forskningsresultaten i denna studie. Vidare forskning krävs för att se om det kan finnas kombinationer med t.ex. selen för att öka effektiviteten för att förebygga prostatacancer.

Xenobiotic biotransformation process and its capacity is crucial for xenobiotic chemicals elimination that may cause damage toward cell structures. The effectiveness of the enzymes included in this process depends on the gene variants that encodes them. The aim of this work was to compare certain polymorphisms of selected genes between cases and control groups. Studied polymorphisms were null genotypes of the glutathione S-transferase gene M1 and T1 and the insertion of TA dinucleotide in the promotor region of UDP-glucuronosyl transferase 1A1. The number of cases group was six included patients with colorectal, lung, prostate, breast, pancreatic and head and neck cancer. Total number of analysed individuals was 1 118 for cancer cases and 470 for healthy controls. The control group was divided into two groups, the first one was called general and the second one was called special included healthy individuals with no cancer history in their closest family members. Gilbert syndrome (GS) is caused by homozygous insertion of the TA dinucleotide in the TATA box of the gene UGT1A1 and it causes elevated bilirubin levels. Bilirubin is a potent antioxidant in human body, so the aim was to attest its protective effect toward cancer. We expected lower frequency of GS as a protective factor in the cases groups compared with controls. This hypothesis was confirmed in the breast cancer group (GS frequency 10,0 %) and pancreatic cancer group (GS frequency 11,1 %). In the general and special control groups the frequency of GS was 16,0 % and 15,4 % respectively. Although the other case groups show lower frequency of GS, the results weren´t statistically significant. Null GSTM1 genotype was observed with 50,4 % frequency in the general control groups and with 55,3 % frequency in the special control group. Neither the one of the cases groups hasn´t showed significantly lower percentage of null genotype. Despite expectation we observed statistically significant lower frequency of null genotype in the group of lung and pancreatic cancer group (37,4 % and 39,3 % respectively). According to this study, we can say that the lack of glutathione S-transferase M1 activity is not a risk factor for cancer development. Null genotype of GSTT1 wasn´t identified in both control groups at all. In case groups of breast and prostate cancer, there was only one individual carrying the null GSTT1 genotype. Statistically significant higher frequency of this polymorphism was observed in patients with colorectal cancer (9,7 %), lung cancer (17,2 %), pancreatic cancer (3,0 %) and head and neck cancer (15,9 %). In these groups the lack of glutathion S-transferase T1 activity might be considered as risk factor for cancer development. Nevertheless, for further verification it needs to take more investigation in this field, especially enlarge the number of patient in the case groups of head and neck, lung and pancreatic cancer.

The theoretical part of this doctoral thesis provides a comprehensive overview on the topic of preparation and subsequent utilization of magnetic derivatives of biological materials for xenobiotic separation from water. Main attention is paid to magnetic modification of waste materials and by-products originating from agricultural and food industry, which represent widely available and low-cost materials, and also to magnetic modification of microbial cells. In addition to the description of magnetic particle preparation and individual developed techniques of magnetic modification, a brief characterization of selected pollutants and a detailed table overview on utilization of magnetically responsive biomaterials for biosorption of organic dyes, heavy metals, pharmaceutical and personal care products together with ubiquitous industrial endocrine disruptors and also of crude oil derivatives is presented. Experimental part of this thesis is focused on the preparation and optimization of new types of magnetic materials. Emphasis is placed on the employment of simple, fast and simultaneously low-cost magnetic modification techniques (e.g., postmagnetization using microwave-synthesized magnetic iron oxides or one-step modification by magnetic fluids). Selected plant materials (barley and rye straw) were chemically modified to significantly (up to five-times) increase the maximum adsorption capacities for tested dyes. All prepared biomaterials exhibited a great magnetic response and simultaneously relatively high adsorption capacity for selected xenobiotics under experimental conditions used. Factors substantially affecting adsorption process, such as pH, initial concentration, incubation time or temperature were also studied. Adsorption equilibrium data were assessed using Langmuir, Freundlich or Sips isotherm models. Experimental data from time dependence study were analyzed by chosen kinetic models, namely the pseudo-first-order and pseudo-second-order ones and by intraparticle diffusion model. Thermodynamic parameters (Gibbs free energy, enthalpy and entropy) describing the nature of adsorption were also included in study.