Novel methods of malignant brain tumor treatment utilizing the tumor microenvironment

Malignant brain tumors constitute a disaster in the lives of patients, either in the form of extremely low survival in glioblastoma, or the serious long-term adverse effects of therapy in medulloblastoma. These two tumor types represent the most common malignant brain entities in adults and children, respectively. Ever since the early 2000’s, no major improvement of patient outcomes occurred. Immunotherapy, which recorded revolutionary successes in several tumor types, has so far failed in brain tumors. This disappointing phenomenon is the result of intrinsic characteristics of glioblastoma and medulloblastoma and their microenvironment. Therefore, other treatment modalities that exploit the distinct attributes of malignant brain tumors are urgently needed.In this thesis, I describe the features of both tumor types and the development of their therapy until today. Moreover, general features of tumor microenvironment are contrasted to the unique aspects of the brain tumor counterpart. Next, I outline the underlying mechanisms of conventional immunotherapy and recount the natural features of both tumors that prevent its effective deployment. Finally, I suggest alternative approaches that circumvent the challenges encountered so far, such as avoiding the blood brain barrier via local treatment administration or focusing on macrophages as the principal agent of immunotherapy instead of T cells. Antisecretory factor (AF), a new agent in cancer treatment, as well as modulation of CD24/Siglec10 “don’t eat me” signaling are examples of the latter.Following is a summary of the four projects. In publication I, the concept of intratumoral temozolomide treatment is investigated from the perspective of tumor immune microenvironment. Publication II describes the effects of AF16 on macrophages and glioblastoma cells. Publication III is a pilot clinical trial of an AF preparation in patients with newly diagnosed glioblastoma. Manuscript IV examines the modulation of CD24 and Siglec10 to reduce antiphagocytic signaling in glioblastoma and medulloblastoma. The impact of this research is represented by the first published immunological effects of local delivery of temozolomide through convection-enhanced delivery in murine glioblastoma; first investigation of AF16, macrophages and tumor cells; first Salovum human cancer trial; laying the groundwork for CD24-Siglec10 signaling modulation in human glioblastoma and medulloblastoma

Evaluation of Environmental Impacts of Organic Farming by LCA method - Greenhouse Gases from Corn Production

Organic farming is perceived as a system with a number of positive impacts on all components of the environment. For more precise assessment of differences in environmental impacts of conventional and organic farming, we need to be able to measure and quantify such impacts. For this the LCA (Life Cycle Assessment) method may be used as a tool. Among other, the LCA method is also an invaluable tool for assessing GHG emissions related to agricultural production. In this paper, the use of LCA for evaluation of GHG emissions from Zea Mays L. growing is presented. The emission load was calculated by the simplified method LCA, impact category: climate change. The calculation was performed by SIMA Pro software with integrated ReCiPe Midpoint (H) method. The functional unit of the system was represented by 1 kg of corn grain. The model life cycle includes the farm phase (field emissions, seed and planting, fertilizers, plant protection products, agrotechnical operations), calculation of field emissions is also included. The results based e.g. on the yields in Cameroon show clear differences between conventional and organic growing of corn. The GHG emissions expressed in CO2e are after calculation on production unit 38.57 % lower in organic farming, compared to conventional farming

Stimulation of mitochondrial oxidative capacity in white fat independent of UCP1: A key to lean phenotype

AbstractWe are facing a revival of the strategy to counteract obesity and associated metabolic disorders by inducing thermogenesis mediated by mitochondrial uncoupling protein-1 (UCP1). Thus, the main focus is on the adaptive non-shivering thermogenesis occurring both in the typical depots of brown adipose tissue (BAT) and in UCP1-containing cells that could be induced in white adipose tissue (WAT). Because contribution of WAT to resting metabolic rate is relatively small, the possibility to reduce adiposity by enhancing energy expenditure in classical white adipocytes is largely neglected. However, several pieces of evidence support a notion that induction of energy expenditure based on oxidation of fatty acids (FA) in WAT may be beneficial for health, namely: (i) studies in both humans and rodents document negative association between oxidative capacity of mitochondria in WAT and obesity; (ii) pharmacological activation of AMPK in rats as well as cold-acclimation of UCP1-ablated mice results in obesity resistance associated with increased oxidative capacity in WAT; and (iii) combined intervention using long-chain n-3 polyunsaturated FA (omega 3) and mild calorie restriction exerted synergism in the prevention of obesity in mice fed a high-fat diet; this was associated with strong hypolipidemic and insulin-sensitizing effects, as well as prevention of inflammation, and synergistic induction of mitochondrial oxidative phosphorylation (OXPHOS) and FA oxidation, specifically in epididymal WAT. Importantly, these changes occurred without induction of UCP1 and suggested the involvement of: (i) futile substrate cycle in white adipocytes, which is based on lipolysis of intracellular triacylglycerols and re-esterification of FA, in association with the induction of mitochondrial OXPHOS capacity, β-oxidation, and energy expenditure; (ii) endogenous lipid mediators (namely endocannabinoids, eicosanoids, prostanoids, resolvins, and protectins) and their cognate receptors; and (iii) AMP-activated protein kinase in WAT. Quantitatively, the strong induction of FA oxidation in WAT in response to the combined intervention is similar to that observed in the transgenic mice rendered resistant to obesity by ectopic expression of UCP1 in WAT. The induction of UCP1-independent FA oxidation and energy expenditure in WAT in response to the above physiological stimuli could underlie the amelioration of obesity and low-grade WAT inflammation, and it could reduce the release of FA from adipose tissue and counteract harmful consequences of lipid accumulation in other tissues. In this respect, new combination treatments may be designed using naturally occurring micronutrients (e.g. omega 3), reduced calorie intake or pharmaceuticals, exerting synergism in the induction of the mitochondrial OXPHOS capacity and stimulation of lipid catabolism in white adipocytes, and improving metabolic flexibility of WAT. The role of mutual interactions between adipocytes and immune cells contained in WAT in tissue metabolism should be better characterised. This article is part of a Special Issue entitled Brown and White Fat: From Signaling to Disease

Populations of Stored Product Mite Tyrophagus putrescentiae Differ in Their Bacterial Communities

Citation: Erban, T., Klimov, P. B., Smrz, J., Phillips, T. W., Nesvorna, M., Kopecky, J., & Hubert, J. (2016). Populations of Stored Product Mite Tyrophagus putrescentiae Differ in Their Bacterial Communities. Frontiers in Microbiology, 7, 19. doi:10.3389/fmich.2015.01046Background: Tyrophagus putrescentiae colonizes different human-related habitats and feeds on various post harvest foods. The microbiota acquired by these mites can influence the nutritional plasticity in different populations. We compared the bacterial communities of five populations of T putrescentiae and one mixed population of T putrescentiae and T fanetzhangorum collected from different habitats. Material: The bacterial communities of the six mite populations from different habitats and diets were compared by Sanger sequencing of cloned 16S rRNA obtained from amplification with universal eubacterial primers and using bacterial taxon-specific primers on the samples of adults/juveniles or eggs. Microscopic techniques were used to localize bacteria in food boli and mite bodies. The morphological determination of the mite populations was confirmed by analyses of CO1 and ITS fragment genes. Results: The following symbiotic bacteria were found in compared mite populations: Wolbachia (two populations), Cardiniurn (five populations), Bartonella-like (five populations), Blattabacteriurn-like symbiont (three populations), and Solitalea-like (six populations). From 35 identified OTUs97, only Solitalea was identified in all populations. The next most frequent and abundant sequences were Bacillus, Moraxella, Staphylococcus, Kocuria, and Microbacteriurn. We suggest that some bacterial species may occasionally be ingested with food. The bacteriocytes were observed in some individuals in all mite populations. Bacteria were not visualized in food boli by staining, but bacteria were found by histological means in ovaria of Wolbachia infested populations. Conclusion: The presence of Blattabacterium-like, Cardinium, Wolbachia, and Solitalea like in the eggs of T putrescentiae indicates mother to offspring (vertical) transmission. Results of this study indicate that diet and habitats influence not only the ingested bacteria but also the symbiotic bacteria of T putrescentiae

Results of time-of-flight transmission measurements for natW at 25 m and 50 m stations of GELINA

Transmission measurements have been performed at the time-of-flight facility GELINA using metallic discs of natural tungsten. The measurements have been carried out at 25 m and 50 m stations using Li-glass scintillators with the accelerator operating at 800 Hz. This report describes the experimental details required to deliver the data to the EXFOR data library, which is maintained by the Nuclear Data Section of the International Atomic Energy Agency (NDS/IAEA) and the Nuclear Energy Agency of the Organisation for Economic Co-operation and Development (NEA/OECD). The experimental conditions and data reduction procedures are described. In addition, full covariance information based on the AGS concept is given such that nuclear reaction model parameters together with their covariances can be derived in a least squares adjustment to the data or the data can be used to validate resonance parameters recommended in evaluated data libraries.JRC.G.2-Standards for Nuclear Safety, Security and Safeguard

Results of transmission measurements for 40Ca at GELINA

Transmission measurements have been performed at a 50 transmission station of the neutron time-of-flight facility GELINA to determine the total cross section for neutron induced reactions on 40Ca. These measurements are part of a collaboration of the Joint Research Centre and the Oak Ridge National Laboratory (US) to improve nuclear data for nuclear criticality safety applications. They have been supported by the EUFRAT project. This report provides the experimental details required to submit the data to the EXFOR data library which is maintained by the Nuclear Data Section of the IAEA and the Nuclear Energy Agency of the OECD. The experimental details, i.e. measurement conditions, sample characteristics, measurement procedures and experimental uncertainty components, together with the data reduction procedures are described. The experimental results including the full covariance information, based on the AGS-formalism, are reported following the latest recommendations of the International Nuclear Data Committee. This includes the information that is required to derive nuclear reaction model parameters together with their covariances by a least squares adjustment to experimental data.JRC.D.4-Standards for Nuclear Safety, Security and Safeguard

Dicarbonyl stress and beta-cell dysfunction

Methylglyoxal may be involved in the early stages of decline in glucose tolerance and decline in pancreatic beta-cell function leading to type 2 diabetes. Methylglyoxal and methylglyoxal-modified proteins increase during short-term increases in glucose concentration, infusion of exogenous methylglyoxal in rats and mice impaired glucose tolerance and glyoxalase 1 (Glo1) prevented beta-cell toxicity. We investigated the role of methylglyoxal and protein glycation on beta-cell function and the development of diabetes, with focus on the interactions of cells with the extracellular matrix. Impairments in adhesion of MIN6 insulinoma cells to methylglyoxal-glycated collagen IV were assessed in vitro using atomic force microscopy force spectroscopy and methylglyoxal glycation adducts within the pancreas visualised by immunostaining. Minimal glycation of collagen IV at integrin binding sites impaired binding of MIN6 cells in vitro and resulted in a 91% decrease in the energy necessary to detach the cells from collagen. Evidence from high fat diet fed mice showed that the methylglyoxal concentration of the pancreas was increased in the insulin resistant, pre-diabetic state with methylglyoxal-derived glycation adducts within the pancreas predominantly localised to the extracellular matrix in vivo. We conclude that glycation of extracellular matrix collagen IV likely impairs adhesion of beta-cells to the extracellular matrix in pre-diabetes in vivo and may thereby contribute to beta-cell glucotoxicity and dysfunction with progression to type 2 diabetes mellitus

The inhibition of fat cell proliferation by n-3 fatty acids in dietary obese mice

ABSTRACT: BACKGROUND: Long-chain n-3 polyunsaturated fatty acids (LC n-3 PUFA) of marine origin exert multiple beneficial effects on health. Our previous study in mice showed that reduction of adiposity by LC n-3 PUFA was associated with both, a shift in adipose tissue metabolism and a decrease in tissue cellularity. The aim of this study was to further characterize the effects of LC n-3 PUFA on fat cell proliferation and differentiation in obese mice. METHODS: A model of inducible and reversible lipoatrophy (aP2-Cre-ERT2 PPARgammaL2/L2 mice) was used, in which the death of mature adipocytes could be achieved by a selective ablation of peroxisome proliferator-activated receptor gamma in response to i.p. injection of tamoxifen. Before the injection, obesity was induced in male mice by 8-week-feeding a corn oil-based high-fat diet (cHF) and, subsequently, mice were randomly assigned (day 0) to one of the following groups: (i) mice injected by corn-oil-vehicle only, i.e."control" mice, and fed cHF; (ii) mice injected by tamoxifen in corn oil, i.e. "mutant" mice, fed cHF; (iii) control mice fed cHF diet with 15% of dietary lipids replaced by LC n-3 PUFA concentrate (cHF+F); and (iv) mutant mice fed cHF+F. Blood and tissue samples were collected at days 14 and 42. RESULTS: Mutant mice achieved a maximum weight loss within 10 days post-injection, followed by a compensatory body weight gain, which was significantly faster in the cHF as compared with the cHF+F mutant mice. Also in control mice, body weight gain was depressed in response to dietary LC n-3 PUFA. At day 42, body weights in all groups stabilized, with no significant differences in adipocyte size between the groups, although body weight and adiposity was lower in the cHF+F as compared with the cHF mice, with a stronger effect in the mutant than in control mice. Gene expression analysis documented depression of adipocyte maturation during the reconstitution of adipose tissue in the cHF+F mutant mice. CONCLUSION: Dietary LC n-3 PUFA could reduce both hypertrophy and hyperplasia of fat cells in vivo. Results are in agreement with the involvement of fat cell turnover in control of adiposity

Les peuplements de millipèdes et de centipèdes résultant du type de gestion des pâturages : résultats préliminaires en République tchèque

The aim of this study was to compare distribution and assemblage structures in centipedes and millipedes in pastures with different management arrangements. The evaluated types of management included sheep grazing, mowing, mulching and various combinations of these treatments. Different foundation modes of pasture were also evaluated – commercial mixtures of fodder crops, local mixtures of seeds with different proportions of dicotyledonous herbs, and spontaneous fallow land. Despite low abundance of both centipedes and millipedes, the most positive effect observed in millipedes was in mulching due to the surplus of dead organic matter. The best way to manage pasture is to use a mixture of local seeds with a high proportion of dicotyledonous herbs as food of highe r substantiality compared to grassLe but de cette étude était de comparer la répartition et les structures des groupements de centipèdes et de millipèdes dans les pâturages en fonction de différents types de gestion. Les types de gestion évalués étaient le pâturage de moutons, le fauchage et le paillage dans diverses combinaisons. Différents modes de fondations de pâturages ont également été évalués - mélange commercial des cultures fourragères, semences locales mélangées avec des proportions différentes de plantes dicotylédones, et une jachère spontanée. Malgré la rareté des centipèdes et des millipèdes, l'effet le plus positif pour les millipèdes a été observé dans le cadre du paillage car celui-ci offre de la matière organique morte. La meilleure façon de gérer le pâturage est d'utiliser un mélange local de semences à forte proportion de plantes dicotylédones comme nourriture de qualité supérieure en comparaison du gazon

An Increasing Need for Productive and Stress Resilient Festulolium Amphiploids:What Can Be Learnt from the Stable Genomic Composition of Festuca pratensis subsp. apennina (De Not.) Hegi?

Genome composition of Festuca pratensis subsp. apennina (De Not.) Hegi, a tetraploid fescue species native to the tall forbs communities of south-eastern Europe at altitudes between 1100 and 2200m a.s.l. has been the subject of some debate by grass taxonomists. Our cytogenetic analyses including fluorescence in situ hybridisation with probes for genomic DNA and selected DNA repeats revealed the species to be allotetraploid and derived from interspecific hybridization between F. pratensis Huds., a species confined to grassland at lower altitudes, and a so far unknown Festuca species. Besides tetraploids, triploids and pentaploids were found growing in Alpine meadows in close association with F. pratensis subsp. apennina. Triploid cytotypes predominated at many sites in Switzerland and Romania, and in some localities, they were the only cytotypes observed. Cytogenetic analyses revealed the triploids to be hybrids between diploid F. pratensis and tetraploid Festuca pratensis subsp. apennina, while the pentaploid cytotypes originated from hybridization between F. pratensis subsp. apennina and hexaploid F. arundinacea Schreb., a closely-related species growing in a close vicinity to F. pratensis subsp. apennina. Parental genomes of F. pratensis subsp. apennina and of the triploid and pentaploid hybrids showed no evidence of homoeologous chromosome pairing and interspecific recombination, supporting previous observation of a disomic inheritance at meiosis, where chromosome pairing was restricted to bivalent associations. A hypothesis is presented that a chromosome pairing regulator(s), reported previously in other polyploid broad-leaved fescue species of the Festuca subg. Schedonorus, is present and functional in F. pratensis subsp. apennina. It is likely that a common ancestors’ genome that carries the chromosome pairing regulator(s) is present in all polyploid broad-leaved fescue species, and its acquisition was a key event that enabled speciation, and development of a polyploid series within Festuca. Identification of a functional chromosome pairing regulator capable of stabilizing advantageous genome combinations in hybrids within the Lolium-Festuca complex would greatly assist in development of stable Festulolium cultivars. Its expression within Festulolium amphiploid cultivars would assist strategies aimed at climate-proofing productive European grasslands to combat exposures to stress conditions