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The outbreak of the worrisome coronavirus disease in 2019 has caused great concern among the global public, especially regarding the need for personal protective equipment with applied antiviral agents to reduce the spread and transmission of the virus. Thus, in our research, chitosan-based bioactive polymers as potential antiviral agents were first evaluated as colloidal macromolecular solutions by elemental analysis and charge. Three different types of low and high molecular weight chitosan (LMW Ch, HMW Ch) and a LMW Ch derivative, i.e., quaternary chitosan (quart-LMW Ch), were used. To explore their antiviral activity for subsequent use in the form of coatings, the macromolecular Chs dispersions were incubated with the model virus phi6 (surrogate for SARS-CoV-2), and the success of virus inactivation was determined. Inactivation of phi6 with some chitosan-based compounds was very successful (>6 log), and the mechanisms behind this were explored. The changes in viral morphology after incubation were observed and the changes in infrared bands position were determined. In addition, dynamic and electrophoretic light scattering studies were performed to better understand the interaction between Chs and phi6. The results allowed us to better understand the antiviral mode of action of Chs agents as a function of their physicochemical properties.

Emperipolesis is considered a physiological phenomena often present in various pathophysiological conditions, but its etiology is still unknown. In this study, we analyzed the number of megakaryocytes and the percentage of emperipoletic cells in the sternal and femoral bone marrow of Wistar rats. Five types in the thrombopoiesis lineage (megakaryoblasts, promegakaryocytes and megakaryocytes - acidophilic, basophilic and thrombocytogenic) were determined. Except for basophilic megakaryocytes, significant differences were found for number of thrombopoietic cells in the sternal and femoral bone marrow. A larger number of thrombocytogenic megakaryocytes were present in the sternal bone marrow. Emperipoletic cells were significantly present in the femoral compared to the sternal bone marrow. Emperipolesis was typical for lymphocytes and neutrophils individually, while emperipolesis with two or more cells within thrombopoietic cell was also present (1-7 %) and significant differences between the sternal and femoral bone marrow were detected. Emperipolesis was found in all analysed rats and it most commonly occured within mature megakaryocytes and rarely megakaryoblasts, while it was not recorded in the promegakaryocytes. The high incidence of megakaryocytes with emperopolesis in rats could be a consequence of “normal” cell retention in the cytoplasm of megakaryocytes while passing blood cells to circulation or related to haematopoietic response due to high incidence of inbreeding.

Vaccination is one of the most efficient strategies for prevention of infection diseases, but with introduction of sub-unit vaccines with lower immunogenicity adjuvants were needed to enhance the immune response. The term adjuvant is from Latin verb adjuvare which means "to aid". Adjuvants have been used in vaccines for more than 90 years. The longest adjuvant history belongs to aluminium salts, but novel adjuvants have been introduced in licensed vaccines in last 30 years. These novel adjuvants are AS04, which consists of aluminium hydroxide and Toll-like receptor 4 (TLR4) agonist monophosphoryl lipid A and is used in hepatitis B vaccine Fendrix ® and HPV vaccine Cervarix ® , emulsion based adjuvants which are part of several influenza vaccines-MF59 (Fluad ® and Focetria ®) and AS03 (Pandemrix ®), AS01 liposomal adjuvant which is combination of two distinct immunostimulatory molecules and is component of herpes zoster and malaria vaccine and virosomes included in hepatits A vaccine (Epaxal ®) and influenza vaccines (Inflexal ® V and Invivac ®). Adjuvant development and better insight into their mechanism of action are of great importance in order to replace empirical with rational use of adjuvants, without affecting vaccine safety.

Cancer is one of the leading causes of morbidity and mortality worldwide and great efforts are underway to develop new therapeutic protocols. One of the approaches is immunotherapy which uses the immune system and its components to fight against cancer. The two main axes of cancer immunotherapy refer to passive and active treatments. Passive immunotherapy includes administration of tumor-specific antibodies and autologous T cells which destroy tumor cells, while active immunotherapy is directed at inducing the patient's own antitumor immune responses and refers to cancer vaccines and immune checkpoint inhibitors. Vaccination of tumor-bearing individuals with tumor cells/antigens or autologous dendritic cells pulsed with tumor antigens may result in enhanced antitumor immune response. However, vaccine design is a complex, multi-component task, and the optimal combinations of antigens, adjuvants, delivery methods and routes of administration need to be precisely defined. Active immunotherapy also addresses the immunosuppressive and tolerogenic mechanisms developed by tumors. This review provides an overview of new results from clinical studies of therapeutic cancer vaccines and discusses their implications for the clinical use, alone or in combination with other immunotherapeutic strategies.

Water scarcity is one of the greatest threats for human survival and quality of life, and this is increasingly contributing to the risk of human, animal and plant infections due to waterborne viruses. Viruses are transmitted through polluted water, where they can survive and cause infections even at low concentrations. Plant viruses from the genus Tobamovirus are highly mechanically transmissible, and cause considerable damage to important crops, such as tomato. The release of infective tobamoviruses into environmental waters has been reported, with the consequent risk for arid regions, where these waters are used for irrigation. Virus inactivation in water is thus very important and cold atmospheric plasma (CAP) is emerging in this field as an efficient, safe, and sustainable alternative to classic waterborne virus inactivation methods. In the present study we evaluated CAP-mediated inactivation of pepper mild mottle virus (PMMoV) in water samples. PMMoV is a very resilient water-transmissible tobamovirus that can survive transit through the human digestive tract. The efficiency of PMMoV inactivation was characterized for infectivity and virion integrity, and at the genome level, using test plant infectivity assays, transmission electron microscopy, and molecular methods, respectively. Additionally, the safety of CAP treatment was determined by testing the cytotoxic and genotoxic properties of CAP-treated water on the HepG2 cell line. 5-min treatment with CAP was sufficient to inactivate PMMoV without introducing any cytotoxic or genotoxic effects in the in-vitro cell model system. These data on inactivation of such stable waterborne virus, PMMoV, will encourage further examination of CAP as an alternative for treatment of potable and irrigation waters, and even for other water sources, with emphasis on inactivation of various viruses including enteric viruses.

This document is an editorial published in the journal Frontiers in Cellular & Infection Microbiology. The editorial focuses on the research implications of microbial virulence factors, resistance, and new therapeutic strategies in the context of future infectious disease therapies. The goal of the research topic is to gather the latest articles addressing these topics and to discuss recent developments and innovative approaches in the field. The editorial highlights several studies, including one on tuberculosis in Poland and northeastern Europe, a transcriptional analysis of human peripheral blood mononuclear cells stimulated with M. tuberculosis, the identification of virulence traits and genes in Kluyvera and Phytobacter, the role of the type VI secretion system in drug resistance in Acinetobacter baumannii, and the antivirulence activity of epigallocatechin-3-gallate against Aeromonas hydrophila. The editorial concludes by stating that the collected papers shed light on selected virulence factors, potential drugs, therapeutic strategies, diagnostics, and the changing epidemiology of microbial infections. [Extracted from the article]

Abstract Background Burkholderia cenocepacia is considered one of the most problematic cystic fibrosis (CF) pathogens. Colonization prevalence in the Serbian CF population is high and virtually exclusively limited to a single highly transmissible clone of B. cenocepacia ST856 which is positive for both the B. cepacia epidemic strain marker (BCESM) and cable pilin, and is closely related to the epidemic strain CZ1 (ST32). Methods Biofilm formation for 182 isolates, and adhesion to components of the host extracellular matrix, proteolytic activity, mucoidy and motility of selected ST856 representatives, as well as B. cenocepacia ST858 and ST859, and B. stabilis ST857, novel STs isolated from Serbian CF patients, were investigated in this study. The presence of the cepI, cepR, fliG, llpE, wbiI, and bcscV genes was analyzed. Results Biofilm-formation ability of analyzed strains was poor under standard laboratory conditions, but changed in stress conditions (cold stress) and conditions that mimic CF milieu (increased CO2). All strains expressed ability to bind to collagen and fibronectin albeit with different intensity. Representatives of ST856 exhibited gelatinase activity. ST858, ST859 and 9/11 of ST856 genotypes were positive for swimming and twitching motility whereas ST857 was non-motile. Mucoidy was demonstrated in all ST856 genotypes, ST857 was semi-mucoid, and ST858 and ST859 were non-mucoid. Molecular analysis for major virulence factors revealed that ST856 and ST857 carried the six analyzed genes, while ST858 and ST859 were negative for the llpE gene. Conclusion Variations in virulence phenotypes in different genotypes of epidemic B. cenocepacia ST856 clone, in vitro, could be a consequence of diversification driven by pathoadaptation. Diversity of epidemic clone genotypes virulence, could be challenging for accurate diagnosis and treatment, as well as for infection control.

Using theory and case study, this paper investigates the economic benefits a city has when it is the country's capital city and pursuant to this what that city would lose if the word „capital“ was removed from it. That it is not about a scientific art for art’s sake situation, speaks the fact that over the last one hundred years in over two hundred counties world wide a completely new or shifted existing capital city has been built. With the help of a series of multipliers, the fiscal and income related effects of „capital “are identified in the existing capital city as are the influences on employment and population numbers of the capital city. In the study of the suggested cases the methodology applied to Zagreb, the capital city of Croatia is suggested. Finally, the scenario of shifting the potential „capital“ to other locations within the country is suggested, whether it be (a) a place where there is no population or applicable infrastructure or (b) another existing town. A third scenario is proposed which disintegrates „capital” and some of its functions and institutions shift to a number of various places within the country. In opposition to political decisions which historically have dominantly determined the location of the capital city, this paper primarily emphasises economic criteria which should ultimately lead to even (polycentric) development of the country as a whole.

The antimicrobial susceptibility testing was conducted on 174 single isolates from poultry farms in Serbia and it was determined that seven Salmonella spp. were multidrug resistant. Sixteen serotypes were detected, but only serotype Infantis confirmed reduced susceptibility to colistin. Seven colistin resistant Salmonella Infantis were studied in detail using the WGS approach. Three sequence types were identified corresponding to different epizootiology region. The isolate from the Province of Vojvodina 3842 and isolates from Jagodina (92 and 821) are represented by the sequence type ST413 and ST11, respectively. Four isolates from Kraljevo are ST32, a common S. Infantis sequence type in humans, poultry and food. The fosfomycin resistance gene fosA7 in isolate 3842 and the vgaA gene in isolate 8418/2948 encoding resistance to pleuromutilins were reported for the first time in serovar Infantis. The changes in relative expression of the phoP/Q, mgrB and pmrA/B genes were detected. Single nucleotide polymorphisms of the pmrB gene, including transitions Val164Gly or Val164Met, and Arg92Pro are described. Analyses of quinolone resistance determining region revealed substitutions Ser83Tyr in GyrA protein and Thr57Ser and Ser80Arg in ParC protein. Based on WGS data, there are two major clusters among analyzed Salmonella Infantis isolates from central Serbia.

Neither the region, as part of the state, nor regional development has occupied the centre of attention in the theory of international trade. There are several reasons, both theoretical and methodological, as well as entirely practical, including the want of any adequate statistics, particularly those necessary for the construction of Croatian regional balances of payments. Accordingly, there are several objectives to this work. After the introduction in which reference is made to the limitations of the running of individual regional economic policies, comes a chapter in which the content of an ideal regional balance of payments is defined. On the way from the ideal to the objective content of regional balances of payments, that is, one reflecting the available data, many methodological problems had to be solved and suitable statistics set up. In the sequel, the analysis of the balances of payments reveals a whole scale of regions that are negative or positive in terms of foreign currency. Although the quantities of the individual balances and items are interesting in themselves, it is important to understand that the different regional exposures to monetary policy possibly require a selective approach from economic policy. At the end, making use of the regional balances of payments, the influence of the depreciation of the kuna on the gross domestic product of the regions is analysed. It is established that in some hypothetical depreciation, if foreign currency transactions were treated ceteris paribus in relation to other economic aggregates, there would be important gains and losses, which would lead to ever greater developmental inequality in Croatia.

Koristeći teoriju i studij slučaja, u ovom se radu istražuju ekonomske koristi koje neki grad ima jer je glavni grad države i, sukladno tome, što bi taj grad izgubio ako bi se „glavno“ iz njega odselilo. Da nije riječ o znanstvenoj l'art pour l'art situaciji, govori činjenica da je u proteklih sto godina u više od dvjesto država širom svijeta izgrađen sasvim novi ili preseljen postojeći glavni grad. Uz pomoć serije multiplikatora, identificiraju se fiskalni i dohodovni efekti „glavnog“ u postojećem glavnom gradu, te utjecaji na zaposlenost i brojnost stanovnika glavnog grada. U studiji slučaja predložena se metodologija aplicira na Zagreb, glavni grad Hrvatske. U završnom dijelu rada razmatraju se scenariji preseljenja potencijalnog „glavnog“ na neku drugu lokaciju u prostoru države, bilo da je riječ (a) o nekoj prostornoj točki u kojoj nema stanovnika ni primjerene infrastrukture ili (b) nekom drugom postojećem gradu. Predložen je i treći scenarij koji dezintegrira „glavno” i pojedine njegove funkcije i institucije seli u veći broj različitih točaka u prostoru države. Nasuprot političkoj odluci, koja je u povijesti dominantno određivala lokaciju glavnog grada, u ovom se radu u prvi plan ističu ekonomski kriteriji koji bi u konačnici trebali voditi ravnomjernijem (policentričnom) razvoju države u cjelini.