Synthetic ganglioside analogues for sensitive biosensing : improved probes for antibodies and bacterial toxins

This thesis describes the synthesis of analogues of human gangliosides and applications thereof for the detection and inhibition of bacterial toxins and antibodies. An efficient glycosylation method was developed for the synthesis of ω-functionalized alkyl lactosides (Chapter 2). These lactosides were further used as starting compounds in chemo-enzymatic syntheses of analogues of human gangliosides GM3, GM2, GM1, GD1a and GalNAc-GD1a (Chapters 3 and 4). In addition, divalent, tetravalent and octavalent GM2 and GM1 gangliosides were obtained (Chapter 5). A complete NMR characterization of the synthesized compounds was performed (Chapter 3). The potential of these ganglioside mimics to detect toxins and antibodies was shown in a variety of diagnostic tests: - in inhibition studies of the synthesized oligosaccharide-linked dendrimers with the cholera toxin B-subunit (Chapter 5) unprecedentedly large multivalency effects were observed: the tetra- and octa- GM1-substituted dendrimers are, respectively, 80 000 and 380 000 times stronger than a monovalent GM1 derivative as binding ligands for the toxin; - in various modified ELISAs the synthetic ganglioside analogues were used to modify the plates (Chapters 3, 4 and 6) and thus tested for their performance in the detection of the cholera toxin B-subunit and the B subunit of E. coli heat-labile enterotoxin; - for the detection of IgG and IgM antibodies in serum samples from neuropathy patients by the covalently attached ganglioside analogues a proof of principle was demonstrated (Chapter 6). <br/

COLLABORATION BETWEEN ECONOMIC OPERATORS SITUATED IN THE WARMIA AND MAZURY REGION AND BUSINESS ENVIRONMENT INSTITUTIONS

Competitiveness of enterprises in North-East Poland is the lowest in this country. Firms in Warmia and Mazury voivodeship need institutional support  from private and public sector. Collaboration between economic operators and business environment institutions is an important issue. Business environment helps boost entrepreneurship and innovation of firms. The core research objective of this article is to diagnose and evaluate the collaboration between economic operators situated in the Warmia and Mazury region and business environment institutions. The research method applied: statistical surveys based on surveys research. Questionnaire was used as a tool in the research. Research conducted at the turn of 2018 and 2019 among 21 economic operators located in the region of Warmia and Mazury (especially in Olsztyn – the biggest city in the region). Economic operators collaborate more often with BEIs from the Warmia and Mazury region than with BEIs from other regions. Most economic operators are not satisfied with the collaboration with BEIs from Warmia and Mazury voivodeship due to lack of important services and activities offered by the institutions, existing barriers and obstacles, as well as the low quality of services offered in the Warmia and Mazury region. The most significant barriers and obstacles to collaboration with BEIs include considerable formalisation and bureaucracy, insufficient skills of personnel, and long waiting time for starting collaborationCompetitiveness of enterprises in North-East Poland is the lowest in this country. Firms in Warmia and Mazury voivodeship need institutional support  from private and public sector. Collaboration between economic operators and business environment institutions is an important issue. Business environment helps boost entrepreneurship and innovation of firms. The core research objective of this article is to diagnose and evaluate the collaboration between economic operators situated in the Warmia and Mazury region and business environment institutions. The research method applied: statistical surveys based on surveys research. Questionnaire was used as a tool in the research. Research conducted at the turn of 2018 and 2019 among 21 economic operators located in the region of Warmia and Mazury (especially in Olsztyn – the biggest city in the region). Economic operators collaborate more often with BEIs from the Warmia and Mazury region than with BEIs from other regions. Most economic operators are not satisfied with the collaboration with BEIs from Warmia and Mazury voivodeship due to lack of important services and activities offered by the institutions, existing barriers and obstacles, as well as the low quality of services offered in the Warmia and Mazury region. The most significant barriers and obstacles to collaboration with BEIs include considerable formalisation and bureaucracy, insufficient skills of personnel, and long waiting time for starting collaboratio

Конституційно-правова природа Ради Міністрів Автономної Республіки Крим: дискусійні питання теорії та практики

У статті розкриваються особливості конституційно-правової природи Ради міністрів Автономної Республіки Крим. Показане місце Ради міністрів Автономної Республіки Крим серед інших органів публічної влади. Ключові слова: Рада міністрів Автономної Республіки Крим, Автономна Республіка Крим, уряд, автономія.В статье раскрываются особенности конституционно-правовой природы Совета министров Автономной Республики Крым. Показано место Совета министров Автономной Республики Крым среди других органов публичной власти. Ключевые слова: Совет министров Автономной Республики Крым, Автономная Республика Крым, правительство, автономия.In the article the features of constitutional and legal status of the Rada of Ministry of the Autonomous Republic of Crimea are analyzed. The place of the Rada of Ministry of the Autonomous Republic of Crimea between others organs of public power is defined. Key words: the Rada of Ministry of the Autonomous Republic of Crimea, the Autonomous Republic of Crimea, government, autonomy

Picomolar inhibition of cholera toxin by a pentavalent ganglioside GM1os-calix[5]arene

Cholera toxin (CT), the causative agent of cholera, displays a pentavalent binding domain that targets the oligosaccharide of ganglioside GM1 (GM1os) on the periphery of human abdominal epithelial cells. Here, we report the first GM1os-based CT inhibitor that matches the valency of the CT binding domain (CTB). This pentavalent inhibitor contains five GM1os moieties linked to a calix[5]arene scaffold. When evaluated by an inhibition assay, it achieved a picomolar inhibition potency (IC50 = 450 pM) for CTB. This represents a significant multivalency effect, with a relative inhibitory potency of 100000 compared to a monovalent GM1os derivative, making GM1os-calix[5]arene one of the most potent known CTB inhibitors

Bacterial toxin inhibitors based on multivalent scaffolds.

Protein toxins released by certain intestinal bacteria are the cause of many diarrhoeal diseases including cholera and travellers' diarrhoea. The toxins enter their target cells by first binding to specific glycolipids in the cell membrane. Inhibition of these protein-carbohydrate interactions has the potential to prevent the toxins from reaching their site of action, and thus avoid the ensuing diarrhoea. Simple oligosaccharides typically have low affinities for the protein toxins, therefore inhibitor design has focussed on exploiting the principles of multivalency: multiple weak interactions acting in concert can enhance the overall binding interaction. The major classes of multivalent inhibitors investigated to date will be discussed; these include glycopolymers, glycodendrimers, tailored glycoclusters and inhibitors exploiting templated assembly

Multivalent glycoconjugates as vaccines and potential drug candidates

Pathogens adhere to the host cells during the first steps of infection through multivalent interactions which involve protein–glycan recognition. Multivalent interactions are also involved at different stages of immune response. Insights into these multivalent interactions generate a way to use suitable carbohydrate ligands that are attached to a basic scaffold consisting of e.g., dendrimer, polymer, nanoparticle, etc., with a suitable linker. Thus a multivalent architecture can be obtained with controllable spatial and topology parameters which can interfere with pathogen adhesion. Multivalent glycoconjugates bearing natural or unnatural carbohydrate antigen epitopes have also been used as carbohydrate based vaccines to stimulate an innate and adaptive immune response. Designing and synthesizing an efficient multivalent architecture with optimal ligand density and a suitable linker is a challenging task. This review presents a concise report on the endeavors to potentially use multi- and polyvalent glycoconjugates as vaccines as well as anti-infectious and anti-inflammatory drug candidates

Evolving biocatalysis to meet bioeconomy challenges and opportunities

4siThe unique selectivity of enzymes, along with their remarkable catalytic activity, constitute powerful tools for transforming renewable feedstock and also for adding value to an array of building blocks and monomers produced by the emerging bio-based chemistry sector. Although some relevant biotransformations run at the ton scale demonstrate the success of biocatalysis in industry, there is still a huge untapped potential of catalytic activities available for targeted valorization of new raw materials, such as waste streams and CO2. For decades, the needs of the pharmaceutical and fine chemistry sectors have driven scientific research in the field of biocatalysis. Nowadays, such consolidated advances have the potential to translate into effective innovation for the benefit of bio-based chemistry. However, the new scenario of bioeconomy requires a stringent integration between scientific advances and economics, and environmental as well as technological constraints. Computational methods and tools for effective big-data analysis are expected to boost the use of enzymes for the transformation of a new array of renewable feedstock and, ultimately, to enlarge the scope of biocatalysis.partially_openopenPellis, Alessandro; Cantone, Sara; Ebert, Cynthia; Gardossi, LuciaPellis, Alessandro; Cantone, Sara; Ebert, Cynthia; Gardossi, Luci

Economic and financial causes of the shadow economy in the European Union

Motywacja: Szara strefa jest problemem o zasięgu globalnym ze względu na powiązania gospodarcze oraz migracje ludności. Nieoficjalna gospodarka występuje w każdym państwie. Jej poziom oraz charakterystyka są uwarunkowane przez czynniki społeczno-kulturowe, ekonomiczne oraz polityczno-prawne. Cel: Celem artykułu jest wskazanie przyczyn powstania i opis rozwoju zjawiska szarej strefy w państwach Unii Europejskiej (UE). Materiały i metody: Wykorzystano krytyczną analizę literatury przedmiotu, zarówno polskojęzycznej, jak i zagranicznej oraz analizę statystyczną. Materiał empiryczny stanowią dane Banku Światowego, Międzynarodowego Funduszu Walutowego, Fundacji Heritage oraz organizacji Transparency International. Wyniki: W 2016 roku odnotowano silną zależność między poziomem szarej strefy a Indeksem Wolności Fiskalnej, Indeksem Percepcji Korupcji oraz PKB per capita. Zdecydowanie słabsza zależności wystąpiła między skalą nieoficjalnej gospodarki a stopą bezrobocia. Jednak nie można uznać, że nie jest to czynnik wpływający na podjęcie decyzji o uczestnictwie w szarej strefie.Motivation: The shadow economy is a global problem due to economic links and population migrations. An unofficial economy exists in every country. Its level and characteristics are determined by the socio-cultural, economic and political-legal factors. Aim: The aim of this article is to identify the causes of the shadow economy phenomenon and the description of its development in the European Union countries. Materials and methods: A critical analysis of the literature on the subject, both Polish and foreign, and a statistical analysis were used. Empirical material is the data of the World Bank, the International Monetary Fund, the Heritage Foundation and Transparency International. Results: In 2016, there was a strong relationship between the level of the shadow economy and the Index of Economic Freedom, the Index of Corruption Perception and GDP per capita. A much weaker relationship occurred between the scale of the unofficial economy and the unemployment rate. However, it cannot be concluded that this is not a factor influencing the decision to participate in the shadow economy