Hybrid Poly(<i>β</i>‐amino ester) Triblock Copolymers Utilizing a RAFT Polymerization Grafting‐From Methodology

The biocompatibility, biodegradability, and responsiveness of poly(β‐amino esters) (PBAEs) has led to their widespread use as biomaterials for drug and gene delivery. Nonetheless, the step‐growth polymerization mechanism that yields PBAEs limits the scope for their structural optimization toward specific applications because of limited monomer choice and end‐group modifications. Moreover, to date the post‐synthetic functionalization of PBAEs has relied on grafting‐to approaches, challenged by the need for efficient polymer–polymer coupling and potentially difficult post‐conjugation purification. Here a novel grafting‐from approach to grow reversible addition–fragmentation chain transfer (RAFT) polymers from a PBAE scaffold is described. This is achieved through PBAE conversion into a macromolecular chain transfer agent through a multistep capping procedure, followed by RAFT polymerization with a range of monomers to produce PBAE–RAFT hybrid triblock copolymers. Following successful synthesis, the potential biological applications of these ABA triblock copolymers are illustrated through assembly into polymeric micelles and encapsulation of a model hydrophobic drug, followed by successful nanoparticle (NP) uptake in breast cancer cells. The findings demonstrate this novel synthetic methodology can expand the scope of PBAEs as biomaterials

Triblock copolymer micelles enhance solubility, permeability and activity of a quorum sensing inhibitor against Pseudomonas aeruginosa biofilms

Antimicrobial resistance is a threat to public health for which new treatments are urgently required. The capability of bacteria to form biofilms is of particular concern as it enables high bacterial tolerance to conventional therapies by reducing drug diffusion through the dense, exopolymeric biofilm matrix and the upregulation of antimicrobial resistance machinery. Quorum sensing (QS), a process where bacteria use diffusible chemical signals to coordinate group behaviour, has been shown to be closely interconnected with biofilm formation and bacterial virulence in many top priority pathogens including Pseudomonas aeruginosa. Inhibition of QS pathways therefore pose an attractive target for new therapeutics. We have recently reported a new series of pqs quorum sensing inhibitors (QSIs) that serve as potentiators for antibiotics in P. aeruginosa infections. The impact on biofilms of some reported QSIs was however hindered by their poor penetration through the bacterial biofilm, limiting the potential for clinical translation. In this study we developed a series of poly(ß-amino ester) (PBAE) triblock copolymers and evaluated their ability to form micelles, encapsulate a QSI and enhance subsequent delivery to P. aeruginosa biofilms. We observed that the QSI could be released from polymer micelles, perturbing the pqs pathway in planktonic P. aeruginosa. In addition, one of the prepared polymer variants increased the QSIs efficacy, leading to an enhanced potentiation of ciprofloxacin (CIP) action and therefore improved reduction in biofilm viability, compared to the non-encapsulated QSI. Thus, we demonstrate QSI encapsulation in polymeric particles can enhance its efficacy through improved biofilm penetration

Financial analysis of ZETO company in the years 2011-2013

Celem niniejszej pracy jest omówienie problematyki związanej z przeprowadzeniem analiz finansowych oraz poddanie analizie finansowej przedsiębiorstwo ZETO w latach 2011-2013. Dokonanie analizy finansowej jest kluczowym etapem w procesie podejmowania decyzji dotyczących dalszego rozwoju jednostki. Błędnie przeprowadzona oraz źle zdefiniowany wynik analizy może kosztować firmę stratę ważnych kontrahentów oraz dłużników co może doprowadzić do zadłużenia jednostkii jej upadłości. Niniejsza praca definiuje finansowe metody oceny działalności i prezentuje w oparciu o wcześniej wykonaną analizę wyniki i wnioski prowadzenia przedsiębiorstwa na przestrzeni trzech lat. Praca jest czytelna, oparta na pozycjach bibliograficznych znanych i cenionych autorów. Pierwszy rozdział stanowi bazę teoretyczną, w którym ujęte zostały i zdefiniowane pojęcia z działu księgowości wywodzące się z płaszczyzny ekonomicznej i finansowej dzięki której praca jest zrozumiała dla każdego odbiorcy.The main goal of this graduation work is to report problematic aspects of performing financial analysis and to analyze company ZETO over the period 2011-2013. Effectuate the financial analysis is a central point in a decision process involving further firm progression. Incorrectly carried out and wrong defined result may cost the company losses important contractors and debtors which may cause indebtedness and bancruptcy. This work is defining financial methods of rating company’s activity and presents powered by accomplished anlyze scores and conclusions of leading the company over the period of three years. This thesis is readable, based on bibliographical positions of famous and appreciated authors. First chapter is a theoretical base with defined concepts of accounting area tracing back from economics and finance, thanks to this work is clear for every receivers

The structural functionalisation of poly(ß-amino esters) for drug delivery to bacterial biofilms

The prevalence of bacterial infections and the rise of antibiotic resistance pose an increasing challenge to human health, solutions to which are urgently needed. Of particular concern is bacterial assembly into biofilms associated with most bacterial infections, with biofilms demonstrated as more resistant to antimicrobial therapies than their planktonic counterparts. The decreased efficacy of conventional antibiotics when targeting biofilms is caused by several factors, including frequent poor penetration through the thick biofilm matrix and susceptibility to bacterial resistance mechanisms, leading to infection recurrence. Additionally conventional therapies are further hindered by their common poor aqueous solubility, off-target toxicity, and premature elimination, thus demonstrating a need for new, alternative treatments against bacterial infections. Drug delivery offers an attractive approach to tackling this challenge as it can improve the drugs pharmacokinetic and pharmacodynamic profiles, enable selective interactions with the infected tissue, and shield the antibiotic from resistance mechanisms, hence improving the therapeutics efficacy. The use of polymer-based drug delivery platforms is particularly of interest due to the versatile nature of polymeric materials, enabling the use of a range of biodegradable and non-biodegradable systems for the delivery of antimicrobials. Within the field of biodegradable polymers poly(ß-amino esters) (PBAEs) have recently attracted considerable attention, due to their facile synthesis and pH-responsive behaviour, leading to the wide application of these materials for gene delivery and in the assembly of polymeric micelles to transport cancer therapeutics. Comparatively the use of PBAEs to deliver antimicrobials has to date been limited and was therefore explored throughout this thesis. To evaluate the suitability of PBAEs for antimicrobial delivery we first addressed a significant limitation associated with their use to date, which involved the lack of a grafting-from methodology for the polymers post-synthetic functionalisation with additional copolymer chains. This was achieved by developing a novel approach to obtain ABA triblock copolymers, assembled by polymerising PBAEs with reversible addition chain transfer (RAFT) monomers, thus enabling the synthesis of polymer libraries with versatile functionalities. We then demonstrated successful particle assembly of the RAFT-PBAE-RAFT polymers, followed by subsequent encapsulation of a model hydrophobic drug within these systems, thus demonstrating their suitability for drug delivery. The RAFT-PBAE-RAFT particles were then evaluated in bacterial biofilm models, with the encapsulation and subsequent delivery of a quorum sensing inhibitor (QSI), administered in a combination therapy with the antibiotic ciprofloxacin (CIP). We demonstrated QSI encapsulation in RAFT-PBAE-RAFT particles can improve the efficacy of the antimicrobial, achieving an improved reduction in biofilm viability when administered as part of the combination therapy. We then set out to expand upon these results further, by attempting to further incorporated CIP in the RAFT-PBAE-RAFT drug delivery platform, through its conjugation to the RAFT copolymer. This approach was found to be unsuccessful, leading to a decrease in antibiotic efficacy following its permanent attachment to the polymer particles. To explore alternative methods for CIP delivery using PBAEs we then attached the antibiotic to linear PBAE chains and tested the efficacy of those systems in two different biofilm models, each time demonstrating an improvement of the antibiotic efficacy. Antibiotic attachment was further shown to delay the bacterial resistance response to the antimicrobial treatment, thus demonstrating this approach as an effective platform for CIP delivery. Overall, this thesis demonstrates the use of PBAE-based drug delivery systems is a versatile and attractive approach to enhance the efficacy of different antimicrobial compounds, particularly when targeting biofilm-associated infections

The structural functionalisation of poly(ß-amino esters) for drug delivery to bacterial biofilms

The prevalence of bacterial infections and the rise of antibiotic resistance pose an increasing challenge to human health, solutions to which are urgently needed. Of particular concern is bacterial assembly into biofilms associated with most bacterial infections, with biofilms demonstrated as more resistant to antimicrobial therapies than their planktonic counterparts. The decreased efficacy of conventional antibiotics when targeting biofilms is caused by several factors, including frequent poor penetration through the thick biofilm matrix and susceptibility to bacterial resistance mechanisms, leading to infection recurrence. Additionally conventional therapies are further hindered by their common poor aqueous solubility, off-target toxicity, and premature elimination, thus demonstrating a need for new, alternative treatments against bacterial infections. Drug delivery offers an attractive approach to tackling this challenge as it can improve the drugs pharmacokinetic and pharmacodynamic profiles, enable selective interactions with the infected tissue, and shield the antibiotic from resistance mechanisms, hence improving the therapeutics efficacy. The use of polymer-based drug delivery platforms is particularly of interest due to the versatile nature of polymeric materials, enabling the use of a range of biodegradable and non-biodegradable systems for the delivery of antimicrobials. Within the field of biodegradable polymers poly(ß-amino esters) (PBAEs) have recently attracted considerable attention, due to their facile synthesis and pH-responsive behaviour, leading to the wide application of these materials for gene delivery and in the assembly of polymeric micelles to transport cancer therapeutics. Comparatively the use of PBAEs to deliver antimicrobials has to date been limited and was therefore explored throughout this thesis. To evaluate the suitability of PBAEs for antimicrobial delivery we first addressed a significant limitation associated with their use to date, which involved the lack of a grafting-from methodology for the polymers post-synthetic functionalisation with additional copolymer chains. This was achieved by developing a novel approach to obtain ABA triblock copolymers, assembled by polymerising PBAEs with reversible addition chain transfer (RAFT) monomers, thus enabling the synthesis of polymer libraries with versatile functionalities. We then demonstrated successful particle assembly of the RAFT-PBAE-RAFT polymers, followed by subsequent encapsulation of a model hydrophobic drug within these systems, thus demonstrating their suitability for drug delivery. The RAFT-PBAE-RAFT particles were then evaluated in bacterial biofilm models, with the encapsulation and subsequent delivery of a quorum sensing inhibitor (QSI), administered in a combination therapy with the antibiotic ciprofloxacin (CIP). We demonstrated QSI encapsulation in RAFT-PBAE-RAFT particles can improve the efficacy of the antimicrobial, achieving an improved reduction in biofilm viability when administered as part of the combination therapy. We then set out to expand upon these results further, by attempting to further incorporated CIP in the RAFT-PBAE-RAFT drug delivery platform, through its conjugation to the RAFT copolymer. This approach was found to be unsuccessful, leading to a decrease in antibiotic efficacy following its permanent attachment to the polymer particles. To explore alternative methods for CIP delivery using PBAEs we then attached the antibiotic to linear PBAE chains and tested the efficacy of those systems in two different biofilm models, each time demonstrating an improvement of the antibiotic efficacy. Antibiotic attachment was further shown to delay the bacterial resistance response to the antimicrobial treatment, thus demonstrating this approach as an effective platform for CIP delivery. Overall, this thesis demonstrates the use of PBAE-based drug delivery systems is a versatile and attractive approach to enhance the efficacy of different antimicrobial compounds, particularly when targeting biofilm-associated infections

VERSENYKÉPES ÉLELMISZERGAZDASÁG – ÉLHETŐ VIDÉK (Négy tézis egy lehetséges fejlesztési politika körvonalainak meghatározásához)

A 20. század végére globális termelési és kereskedelmi rendszerek alakultak ki az élelmiszergazdaságban. Ezek alapvető jellemzője, hogy a korábban általá-nosan alkalmazott piacvédelmi rendszerek lebomlásával párhuzamosan egyre inkább a termékek ára és minősége válik meghatározóvá. Az Európai Unió napjainkban még képes ugyan ideig-óráig fenntartani a „belső” piacok védelmét, ez azonban valószínűleg nem sokáig marad így. A 2007-13 időszakban olyan agrárgazdaság kialakítására indokolt törekedni, mely magában hordozza a hosszú távú, a mindinkább liberalizálódó és globalizálódó világgazdaság feltételrendszerei között is fenntartható fejlődés lehetőségét. (1) Ennek érdekében a magyar agro-ökológiai adottságokat messzemenően figyelembe vevő, a precíziós mezőgazdaság eszközeit sokoldalúan alkalmazó térszerkezet és térbeli munkamegosztás kialakítására van szükség. Ezeket figyelembe véve kell felhasználni a logisztikai rendszerek fejlesztésére rendelkezésre álló erőforrásokat is. (2) A vidéki népesség megtartásában, a tájban levő lehetőségek kiaknázásában kiemelkedő jelentősége lehet a kis és közepes méretű élelmiszeripari üzemeknek. Ezek kialakításában a rendszerszemlélet következetes alkalmazására épülő, a termékpálya minél nagyobb részét magában foglaló szövetkezeteknek a jelenleginél nagyobb szerepet célszerű kapniuk. Csökkenteni kell azon esetek számát, amikor a támogatások pusztán a nyersanyag elő-állításának lehetőségét teremtik meg. (3) A nagyméretű kiskereskedelmi rendsze-rek térhódításával párhuzamosan fokozódik ezek nyomása a beszállítók felé. A késedelmes fizetések, a minden alapot nélkülöző egyéb fizetési kötelezettségek kikötése közgazdasági lényegét tekintve eszközátadást jelent, mely azonban a jelenlegi információs rendszerekben és adójogszabályokban nem tükröződik. Az ilyen esetek rendszeres nyilvántartása és az erre alapozott adóztatás komplex rendszerének kidolgozása alapvető fontosságú feladat a vertikum egészére jellemző egyensúlytalanságok csökkentése érdekében. (4) A magyar agrárium versenyképessége alapvetően belföldön dől el. Ennek érdekében vissza kell adni a magyar fogyasztó hazai termékekbe vetett bizalmát. Ez a jelenlegi élelmiszer-biztonsági rendszer radikális átalakítását követeli meg. - By the end of the 20th century, global systems of production and commerce had developed in the agrobusiness. The fundamental characteristic of these is that parallel to the disintegration of earlier market protection systems generally in use, the price and quality of products increasingly becomes determinant. While the EU is presently still capable of maintaining “internal” market protection for a short time, this is unlikely to be the case for long. In the period 2007-13, the type of agrobusiness whose development is indicated, is one which contains within itself the potential for long-term sustainable development, even within the increasingly liberalised and globalised world economy’s system of conditions. (1) To further this requires the development of a configuration and spatial division of labour that comprehensively utilises the precise tools of agriculture and takes into account Hungarian agro-ecological assets. The resources available for the development of logistical systems should also be utilised taking these into account. (2) Small and medium-sized food industry businesses could have an outstanding significance in making the most of an area’s inherent possibilities and in retaining countryside population. It is advisable in their development, to give the associations that build on the consistent utilisation of system elements and which comprise an increasingly large part of the production field, a much greater role than they currently have. The number of cases where subsidies simply create the opportunity for raw material production must be reduced. (3) The expansion of large-scale small business systems is concurrently putting increased pressure on suppliers. In economic terms, late payments and the stipulation of other, quite baseless, payment obligations constitute a transfer of resources, which is not, however, reflected in the current information systems or in tax legislation. In the interests of reducing the imbalance, characteristic of the whole verticum, the regular recording of such cases and the development of a complex taxation system based on this is a task of fundamental importance. (4) The competitiveness of the Hungarian agricultural sector is basically domestically determined. In the interests of this, the Hungarian consumer’s trust in domestic produce needs to be restored. This requires a radical transformation of the current food security system

Molecular mechanisms of ZC3H12C/Reg-3 biological activity and its involvement in Psoriasis pathology

The members of the ZC3H12/MCPIP/Regnase family of RNases have emerged as important regulators of inflammation. In contrast to Regnase-1, -2 and -4, a thorough characterization of Regnase-3 (Reg-3) has not yet been explored. Here we demonstrate that Reg-3 differs from other family members in terms of NYN/PIN domain features, cellular localization pattern and substrate specificity. Together with Reg-1, the most comprehensively characterized family member, Reg-3 shared IL-6, IER-3 and Reg-1 mRNAs, but not IL-1 beta mRNA, as substrates. In addition, Reg-3 was found to be the only family member which regulates transcript levels of TNF, a cytokine implicated in chronic inflammatory diseases including psoriasis. Previous meta-analysis of genome-wide association studies revealed Reg-3 to be among new psoriasis susceptibility loci. Here we demonstrate that Reg-3 transcript levels are increased in psoriasis patient skin tissue and in an experimental model of psoriasis, supporting the immunomodulatory role of Reg-3 in psoriasis, possibly through degradation of mRNA for TNF and other factors such as Reg-1. On the other hand, Reg-1 was found to destabilize Reg-3 transcripts, suggesting reciprocal regulation between Reg-3 and Reg-1 in the skin. We found that either Reg-1 or Reg-3 were expressed in human keratinocytes in vitro. However, in contrast to robustly upregulated Reg-1 mRNA levels, Reg-3 expression was not affected in the epidermis of psoriasis patients. Taken together, these data suggest that epidermal levels of Reg-3 are negatively regulated by Reg-1 in psoriasis, and that Reg-1 and Reg-3 are both involved in psoriasis pathophysiology through controlling, at least in part different transcripts