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Warsaw, Poland

The Warsaw University of Life science is the largest agricultural university in Poland. It was founded in 1816. Wikipedia.

Dzik J.M.,Warsaw University of Life Sciences
Frontiers in Immunology | Year: 2014

Two main types of macrophage functions are known: classical (M1), producing nitric oxide, NO, and M2, in which arginase activity is primarily expressed. Ornithine, the product of arginase, is a substrate for synthesis of polyamines and collagen, important for growth and ontogeny of animals. M2 macrophages, expressing high level of mitochondrial arginase, have been implicated in promoting cell division and deposition of collagen during ontogeny and wound repair. Arginase expression is the default mode of tissue macrophages, but can also be amplified by signals, such as IL-4/13 or transforming growth factor-β (TGF-β) that accelerates wound healing and tissue repair. In worms, the induction of collagen gene is coupled with induction of immune response genes, both depending on the same TGF-β-like pathway. This suggests that the main function of M2 "heal" type macrophages is originally connected with the TGF-β superfamily of proteins, which are involved in regulation of tissue and organ differentiation in embryogenesis. Excretory-secretory products of metazoan parasites are able to induce M2-type of macrophage responses promoting wound healing without participation of Th2 cytokines IL-4/IL-13. The expression of arginase in lower animals can be induced by the presence of parasite antigens and TGF-β signals leading to collagen synthesis. This also means that the main proteins, which, in primitive metazoans, are involved in regulation of tissue and organ differentiation in embryogenesis are produced by innate immunity. The signaling function of NO is known already from the sponge stage of animal evolution. The cytotoxic role of NO molecule appeared later, as documented in immunity of marine mollusks and some insects. This implies that the M2-wound healing promoting function predates the defensive role of NO, a characteristic of M1 macrophages. Understanding when and how the M1 and M2 activities came to be in animals is useful for understanding how macrophage immunity, and immune responses operate. Vertebrate macrophages play an innate defense role against various pathogens. They perform phagocytosis, bacterial killing, defend against protozoan and metazoan parasites and take part in wound healing. To fulfill such protective functions, "resting" macrophages must be activated. Two main types of macrophage functions have been identified: classical (M1), producing nitric oxide (NO), and M2-type, in which arginase (producing the healing molecule, ornithine) is expressed (1, 2). These responses from macrophages demand different cascades of biochemical reactions, which are regulated by specific sets of cytokines. M1 type can be stimulated by pathogen associated molecular patterns (PAMP) or amplified by T cell cytokines, such as IFN-γ. In contrast, M2 activity is the resident tissue type, and can be amplified by molecules such as IL-4/IL-13, and transforming growth factor-β (TGF-β). Local signals polarize macrophages to an appropriate response. These immune functions are indispensible for both life of an individual and lasting of a species. It is apparent that macrophages, as well as other cells of innate immune response acting in vertebrates, have their deep evolutionary roots in cells serving similar function in ancestral invertebrates. Various names have been used to define such cells in different invertebrate groups, i.e., hemocyte, coelomocyte, amebocyte, or plasmatocyte, collectively named immunocytes (3). However, regardless of the terminology, they perform the same immune functions, and are of similar morphology. Macrophages, the professional phagocytic cells in humans, derive from circulating monocytes or by self renewal in the tissues, and acquire new morphological and physiological characteristics according to the organs and microenvironments, in which they settle. However, this unitarian origin is uncertain for circulating and tissue phagocytes (immunocytes) in invertebrates (3). Immunocytes and macrophages share ability to be activated by non-self material and to react through the release a variety of biologically active molecules such as cytokines, NO, reactive oxygen species, hydrolytic enzymes, and neuroendocrine mediators. In vertebrate immunity, various organs and immune cells are involved, while all the molecules determining invertebrate immune response are harbored in the immunocytes. From the perspective of this review, the multifunctional role of invertebrate cells seems instructive in respect to its inheritance by vertebrates. In search for selection pressure for macrophage differentiation into M1 and M2 phenotypes, it is tempting to look back to recognize which of the functions of M1 macrophages is aligned straight with invertebrate immunocytes and is found possibly in the most primitive invertebrates. Accumulated evidences strongly suggest that a primary function of M2 macrophages is tissue repair and wound healing (4, 5). This process demands polyamines and collagen synthesis what strongly depend on arginase activity (6). © 2014 Dzik. Source

Stobiecka M.,Warsaw University of Life Sciences
Biosensors and Bioelectronics | Year: 2014

Recently discovered effects of plasmonic field on molecular fluorescence offer new insights into the optical interactions at the nanoscale which can help solving problems encountered in widely applied fluorescent labeling of biomolecules for studying life processes in biomedicine and pharmacy. In this work, we have focused on exploring a novel sensitivity-enhancing phenomenon based on protein modulation of plasmon-controlled fluorescence. We have demonstrated that a protein (cytochrome c (Cytc c) or bovine serum albumin (BSA)) can be employed to gate fluorescence resonance energy transfer occurring from a fluorescein isothiocyanate fluorescent dye to plasmonic citrate-capped gold nanoparticles. By applying plasmonic field gated by protein, facilitated by the formation of multi-shell nanoparticles, (AuNP@Cit/Cytc-FITC or AuNP@Cit/BSA-FITC), low limits of detection for Cyt c (LOD=370. pM) and for BSA (LOD=1.8. nM) have been achieved even for large fluorophore:protein ratios, up to 30:1 (over-labeling), normally plagued with energy migration and background fluorescence problems. Control experiments confirming adsorption of proteins on AuNPs have been performed using light scattering and piezometric techniques. The proposed nanoassay may be applied in microanalysis of trace amounts of proteins, e.g. in microfluidic devices. © 2013 Elsevier B.V. Source

Kaluza J.,Warsaw University of Life Sciences | Akesson A.,Karolinska Institutet | Wolk A.,Karolinska Institutet
Circulation: Heart Failure | Year: 2014

Background-Epidemiological studies of red meat consumption in relation to risk of heart failure (HF) are scarce. We examined the associations of unprocessed and processed red meat consumption with HF incidence and mortality in men. Methods and Results-The population-based prospective Cohort of Swedish Men included 37 035 men, aged 45 to 79 years, with no history of HF, ischemic heart disease, or cancer at baseline. Meat consumption was assessed with a selfadministered questionnaire in 1997. During a mean follow-up of 11.8 years, 2891 incidences and 266 deaths from HF were ascertained. Consumption of processed meat was statistically significant positively associated with risk of HF in both age- and multivariable-adjusted models. Men who consumed ≥75 g/d processed meat compared with those who consumed <25 g/d had a 1.28 (95% confidence interval, 1.10-1.48, P trend=0.01) higher risk of HF incidence and 2.43 (95% confidence interval, 1.52-3.88, P trend<0.001) higher risk of HF mortality. The consumption of unprocessed meat was not associated with increased risk of incidence of HF or mortality from HF. Conclusions-Findings from this prospective study of men with low to moderate red meat consumption indicate that processed red meat consumption, but not unprocessed red meat, is associated with an increased risk of HF. © 2014 American Heart Association, Inc. Source

Zakowska-Biemans S.,Warsaw University of Life Sciences
British Food Journal | Year: 2011

Purpose: The purpose of this paper is to examine consumers' motives for food choice and to reveal beliefs about organic food. Design/methodology/approach: The paper is based on results of a survey conducted on a sample of 1,010 Polish consumers. The questionnaire included items to identify food choice motives, attributes of organic food and barriers to buy organic products. The data collected was analyzed with SPSS 15.0 using descriptive statistics and carrying out two step cluster analysis to identify consumers' segments. To get better insight into factors decisive to organic food consumption, the segments were profiled according to declared consumption of organic food. Findings: Sensory factors were the most important motives for food choice, followed by price and safety. Consumers with convenience and price orientation in their food choices were less inclined to buy organic products while consumers open to novelties and willing to try new foods more often declared to buy organic products. Polish consumers conceptualize organic food referring to aspects such as healthiness and safety. Despite the developments observed in the organic food sector in Poland, the information related that barriers to buy organic food still prevail. Research limitations/implications: The choice of validated scale items related to food choice and food related lifestyle was limited and there is a need to further explore Polish consumers food related lifestyle and its relation to organic food consumption. Cluster analysis used to identify segments is a method not based on probabilistic statistics, so it is the researcher's interpretation that is most relevant. Originality/value: Prior research concerning Polish consumers food choices with relation to organic food consumption is very limited. Such information is particularly pertinent to food manufacturers and distributors to support developing communication strategies to stimulate organic food market development in Poland. © Emerald Group Publishing Limited. Source

Grodzik M.,Warsaw University of Life Sciences
International journal of nanomedicine | Year: 2011

The objective of the study was to determine the effect of carbon nanoparticles produced by different methods on the growth of brain tumor and the development of blood vessels. Glioblastoma multiforme cells were cultured on the chorioallantoic membrane of chicken embryo and after 7 days of incubation, were treated with carbon nanoparticles administered in ovo to the tumor. Both types of nanoparticles significantly decreased tumor mass and volume, and vessel area. Quantitative real-time polymerase chain reaction analysis showed downregulated fibroblast growth factor-2 and vascular endothelial growth factor expression at the messenger ribonucleic acid level. The present results demonstrate antiangiogenic activity of carbon nanoparticles, making them potential factors for anticancer therapy. Source

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