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Background/Aim: Treatment of infections caused by biofilm-producing multidrug-resistant (MDR) pathogens represents a huge global problem due to primary antimicrobial multi-resistance enhanced by reduced penetration of antibiotics in the biofilm-embedded bacteria. The aim of this study was to determine the capacity of biofilm production among MDR Acine-tobacter baumannii (A. baumannii) isolates obtained from different clinical specimens and to evaluate the inhibitory effect of selenium nanoparticles (SeNPs) coated with cationic polymer cetyltrimethylammonium bromide (CTAB) on the biofilm formation. Methods: Antimicrobial effect of antibiotics (meropenem, imipenem, gentamicin, amikacin, ciprofloxacin, levofloxacin and trimethoprim-sulfa-methoxazole) was determined by disk-diffusion assay, while sensitivity to colistin was determined with E test. All 60 isolates were tested on biofilm production in microtiter plates with crystal violet dye. Minimal biofilm inhib-itory concentration (MBIC) of SeNPs was tested in order to prevent biofilm formation in microtiter plates. Results: All tested clinical isolates were classified as MDR (n = 60) and extensively drug-resistant (XDR, n = 60). Out of the total 60 isolates, 55 isolates (92 %) showed the ability for biofilm formation, with the majority of them classified as strong (42 %) and moderate (42 %) biofilm producers. MBIC values of SeNPs for 55 biofilm-producing isolates ranged from 0.07 to 1.25 mg/mL. Strong biofilm producers had statistically higher MBIC (0.15 mg/mL) in correlation to other biofilm-producing isolates (0.07 mg/ mL). There was no correlation between invasiveness of isolates with biofilm production and MBIC values. Conclusion: Presented results are very promising and interesting especially in nanotechnology and medical fields, while SeNPs with the addition of cationic surfactant inhibit biofilm formation of MDR A. baumannii clinical isolates.

Head and neck cancers (HNC) are a heterogeneous group of diseases. Histopathological, these are head and neck squamous cell carcinoma (HNSCC) epithelium of the skin, mucosa of the upper aerodigestive tract, pharynx and larynx. HNSCC is the fifth leading cause of cancer worldwide. The most important risk factors are alcohol and smoking. In the recent years, the studies have been conducted in order to prove the role of HPV in HNSCC carcinogenesis. The prevalence of HPV in HNSCC is 30%. HPV is often detected in biological materials of males. People with HPV positive HNSCC respond better to treatment and have a better treatment outcome than patients with no proven HPV. In the future, HPV should be the marker that will influence the choice of therapy in patients with HNSCC, but also the factor that will indicate the outcome of this malignancy in the human population.

Introduction: During the last two and a half years, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has spread around the world. Most of the SARS-CoV-2 vaccines are designed to produce anti-SARS-CoV-2 immunoglobulin G (IgG) against the viral S-glycoprotein. The aim of this study was to measure the anti-S antibody titres among the medical personnel who had been fully vaccinated with different types of vaccines, and to compare them with those who were COVID-19 convalescents. Material and methods: In this study serum was collected from 261 healthcare workers, of whom 227 were vaccinated, while 34 were recovered participants who were not immunised. Serum samples were collected 21 days after the first dose and 60 and 180 days after the second dose of the vaccines and tested with a commercial ELISA kit. Results: The highest antibody level (12 AU/ml) was measured in the Pfizer-BioNTech group, followed by Sinopharm (9.3 AU/ml), Sputnik V (5.9 AU/ml), Sinovac (4.6 AU/ml) and Oxford/Astra- Zeneca vaccine (2.5 AU/ml) 60 days after the second dose of the vaccines (90 days after the first dose). The seropositivity rate for mRNA vaccine was 88.5%, for vector vaccines 86.2% and for inactivated vaccines 71.4%. When comparing these antibody levels with COVID-19 convalescents, higher antibody titres were found in vaccinated participants (5.76 AU/ml vs 7.06 AU/ml), but the difference was not significant (p = 0.08). Conclusions: Individuals vaccinated with mRNA and vector vaccines had a higher seroconversion rate compared to the group vaccinated with inactivated vaccines, or convalescents. [ABSTRACT FROM AUTHOR]

The purpose of this research is to explore howinvestment in r&d, training of employees, branding and reputation, design and acquisition of technology affect business performance measured in terms of turnover growth in firms operating in eu countries at different levels of innovation performance. This study contributes to the literature by identifying activities that lead to business growth of firms in less innovative countries for which r&d is less relevant. Empirical part of the paper relies on survey data from Flash Eurobarometer 433 (European Commission 2016). Research findings reveal rather complex story behind business growth of firms across eu countries. Impact of r&d on business growth indeed varies across eu countries at different levels of innovativeness. In countries at lower level of innovativeness business growth relies on training of employees, branding and reputation as well as acquisition of new technologies. [ABSTRACT FROM AUTHOR]

Healthcare workers (HCW) in primary healthcare centres in the Republic of Srpska, Bosnia and Herzegovina, are on the first combat line with COVID-19. This study aimed to assess the seroprevalence of SARS-CoV-2 among HCW at the primary healthcare centres and to analyse the risk exposure to COVID-19, clinical signs and vaccination status. A cross-sectional study was conducted among HCW at the selected primary healthcare centres between 19 March and 30 April 2021. Antibodies against the SARS-CoV-2 virus were detected by enzyme-linked immunosorbent assay (ELISA). A total of 1,023 HCW (mean age 45 years; 71% female) were included in the study. The anti-SARS-CoV-2 antibodies were detected in 69.5% of all participants. There was a significant difference in seropositivity among primary healthcare centres from different geographical regions. As many as 432 (42%) of all participants had confirmed COVID-19 symptoms before the study and, 84.8% of them were seropositive. This study showed that 702 primary HCW were vaccinated with any of these vaccines: Sputnik V, Sinopharm, Pfizer/Biontech. High titre of SARS-CoV-2 antibodies was found amongst those who received one (92.6%) or both (97.2%) doses of vaccines. In this study, we report high prevalence of SARS-CoV-2 antibody among HCW in primary healthcare in the Republic of Srpska, Bosnia and Herzegovina during the third pandemic wave. [ABSTRACT FROM AUTHOR]

Even though the Internet usage is perceived to be widespread, senior citizens are relatively more reluctant to adopt new technologies. By relying on the Eurostat's Community Statistics on Information Society (CSIS) microdata for the period 2008–2017, we explore recent evolution of the digital divide across Europe. We analyse the difference in adoption of e-governance by younger and older Internet users as well as their reasons for not using e-government services (specifically by submitting completed forms to public authorities). Additionally, we seek to identify factors that determine the difference in the reluctance to adopt e-governance services by senior citizens and the young. By adopting Heckman selection methodology, we establish three categories of factors: those that have different effects for young and old (gender, household size, and population density), those having similar effects (economic activity), and those that have adverse effects for the young and the old (education). Based on empirical results, we suggest following venues for EU-wide policy actions: special attention should be given to older population in sparsely populated areas, specialised learning activities should be developed for older citizens with additional effort to promote inclusion of older women to participate in these learning activities. [ABSTRACT FROM AUTHOR]

Chemical and physical stability, high adsorption capacity and low-toxicological profile are very important features for application of nanoparticles (NPs) in the biomedical field. Physicochemical and biochemical characteristics of nanoparticles are very much dependent on the synthesis method. One of the promising, environmentally conscious method is the green synthesis of NPs using plant extracts. The aim of the this research was to present new plant extract for the synthesis of zinc oxide nanoparticles (ZnO NPs) and to test antimicrobial activity of in this way obtained ZnO NPs. In this study acetonic extract of flowers of Geranium robertianum L. (Geraniaceae) was used for phytosynthesis of zinc oxide nanoparticles (ZnO NPs). G. robertianum aerial parts are a good source of plant phenolics, particularly flavonoids which have an important role in metal nanoparticle synthesis. Total flavonoid content (4.2%) of acetonic extract used in ZnO NPs synthesis was determined by aluminum chloride spectrophotometric assay on 425 nm. Characterization of ZnO nanoparticles obtained by phytosynthesis procedure was done using UV/VIS spectrophotometry and IC spectroscopy. Obtained ZnO NPs were also tested as potential antimicrobial agents, considering that microorganisms rarely develop antimicrobial resistance against NPs. The Muller-Hinton agar well diffusion method was used for evaluation of ZnO NPs antimicrobial activity against Gram negative (Escherichia coli, Acinetobacter baumannii, and Pseudomonas aeruginosa) and Gram positive (three clinical isolates of Staphylococcus aureus) bacteria. The total flavonoid content of acetonic extract of flowers of G. robertianum used for ZnO NPs synthesis was 4.2%. The size of obtained ZnO NPs was approximately 40 nm. All three S. aureus isolates exhibited sensitivity (average value of inhibition zones around 15 mm), while Gram-negative bacteria were resistant to ZnO NPs activity. The results from our study confirm that acetonic extract of flowers of G. robertianum can be used for synthesis of ZnO NPs with significant antimicrobial activity towards Gram-positive bacteria. [ABSTRACT FROM AUTHOR]

Recent research on nanocomposites as potential pharmaceutical carriers, is focused on utilization of inorganic matrices with layered structure in which bioactive molecules/drugs are incorporated. One of the promising inorganic material with such layered structure is clay, which is quite common ingredient in pharmaceutical products, both as excipient or active substance. Clay minerals are not only "inert ingredients", but they can also be used to decrease or increase dissolution rate, delay and/or target drug release, to prevent possible side effects, taste masking or increase stability. Prosperity of clay-based drug delivery systems depends on the amount of a drug retained by the clay, on its release kinetics and on the total amount released during therapeutic regime. Thus, it is very essential to understand and to improve the physico--chemical aspects of drug--clay complexes. The aim of this research is to provide more information on drug-clay stability formulations. Pyrophyllite clay, (Parsovići, Konjic, Bosnia and Herzegovina), Al2Si4O10(OH)2, is a smectite clay type (talc-pyrophyllite group) and was used here as a potential pharmaceutical carrier. Stability of pyrophillite and bioactive molecule/drug was estimated by use of thermal analysis methods (differential thermal analysis/ thermogravimetric analysis - TGA/DTA) and Fouriertransform infrared spectroscopy (FTIR). Additionally detailed kinetic study was done using contemporary kinetic software in order to evaluate kinetics of clay/ bioactive molecule (drug) complex. Antimicrobial study was performed against Staphylococcus aureus (Gram positive bacteria) and Escherichia coli (Gram In epruvetes with 9.9 mL of Muller- Hinton broth and 0.1 mL of bacterial inoculum adjusted to 0.5 McFarland standard was added 1 gram of sterilized pyrophillite. Incubation with 120 rpm shaking was performed during 24h at 37 °C. Decomposition of neat pyrophillite is one-step process with following kinetic triplet: Ea (activation energy) - 216 kJ/mol; A (pre-exponential factor) - 4.1687 x 1010 s-1 and N-th order model, while clay/drug mixture decomposition is a four step process. Third stage in mixture decomposition is of special interest, because decomposition of pyrophillite is happening there. Kinetic parameters for the third stage are as follows: Ea - 176 kJ/mol, A -- 6.537 x 108 s-1 and the N-th order model also gave the best fit. After overnight incubation, we noticed highly significant removing of both bacteria from broth. Staphylococcus aureus was reduced from 2.3 x 109 s-1 cfu/mL to 5.5 x 106 s-1 cfu/mL, while Escherichia coli was reduced from 4.5 x 1011 s-1 cfu/mL to 3.5 x 108 s-1 cfu/ mL. Based on the kinetic results we can conclude that thermal stability of pyrophillite is slightly lowered comparing to neat pyrophillite data, but on the other hand pyrophillite did not make any impact on thermal stability of other components in mixture. This information is of great interest for stability assessment of clay/drug mixture. [ABSTRACT FROM AUTHOR]

The potential problems of DNA extraction from formalin‐fixed paraffin‐embedded (FFPE) tissue samples and amplification efficiency of Human papilloma virus (HPV) may occur in the molecular studies of head and neck squamous carcinoma (HNSCC). The aim of this study was to compare HPV detection rate in FFPE tissues of oral, oropharyngeal, hypopharyngeal, and laryngeal cancers using two silica‐based extraction kits and three amplification methods. A total of 50 FFPE specimens from HNSCC tissues were analyzed. The quality and quantity of the extracted DNA were tested by spectrophotometry. HPV DNA was detected using a single polymerase chain reaction (PCR), a nested PCR, and a Real‐time PCR kit. Statistically significantly higher DNA quality and quantity was observed using the QIAamp DNA FFPE Tissue Kit than when using the QIAamp DNA Mini Kit. There was not HPV amplification in any of the 50 FFPE samples using the single PCR and Real‐time PCR kits, whereas HPV DNA was detected in 22% of samples using nested PCR. Comparing results of the three different methods showed that HPV DNA was detected only with nested PCR. The results presented imply that nested PCR is the most appropriate method for the detection of HPV DNA in FFPE samples, along with adequate DNA extraction methods. [ABSTRACT FROM AUTHOR]

Background/Aim. The oral cavity and oropharyngeal cancers are among the most common cancers worldwide with the multifactorial etiology. The aim of this study was to determine the major risk factors among patients with oral cavity and oropharyngeal tumors in Serbia. Methods. A total of 63 patients with biopsy proven malignant (33 patients) or benign (30 patients) oral cavity or oropharyngeal lesions were included in this study. The data about gender, age, smoking habits and alcohol consumption were obtained from the routine medical files. The detection and genotyping of human papillomavirus (HPV) was done in paraffin embedded tissue samples using in situ hybridization. Results. Malignant lesions were more frequent in men, smokers and patients who consume alcohol with a statistically significant difference compared to the patients with benign lesions. The prevalence of HPV infection was higher in patients with malignant lesions compared to patients with benign lesions, but without statistically significant difference. High risk genotypes were detected only in patients with malignant lesions of tonsils and base tongue cancer, while low risk types were demonstrated in patients with benign lesions with a highly statistically significant difference. Conclusion. The results point to the significant association of tobacco smoking, alcohol consumption and high risk HPV genotypes as risk factors for oral cavity and oropharyngeal carcinomas in Serbian patients. [ABSTRACT FROM AUTHOR]

The purpose of this research is to explore howinvestment in r&d, training of employees, branding and reputation, design and acquisition of technology affect business performance measured in terms of turnover growth in firms operating in eu countries at different levels of innovation performance. This study contributes to the literature by identifying activities that lead to business growth of firms in less innovative countries for which r&d is less relevant. Empirical part of the paper relies on survey data from Flash Eurobarometer 433 (European Commission 2016). Research findings reveal rather complex story behind business growth of firms across eu countries. Impact of r&d on business growth indeed varies across eu countries at different levels of innovativeness. In countries at lower level of innovativeness business growth relies on training of employees, branding and reputation as well as acquisition of new technologies. [ABSTRACT FROM AUTHOR]

Some intestinal nematodes of dogs and cats show zoonotic potential, and therefore they are of public-health significance. In the territory of the city of Banja Luka, 149 samples were examined (131 of dogs and 18 cats), with 40 samples of dog feces collected from two public areas in the city. Parasitological examination (saturated zinc sulfate floatation and determination of larvae and adult parasites in feces) resulted in the following data: Toxocara canis (9.16%), Ancylostomatidae (5.34%), Trichuris vulpis (7.63%), Toxascaris leonina (1.52%), Toxocara cati (33.3%), Trichuris spp. (5.5%) and Hydatigera taeniaeformis (5.5%). On the basis of the obtained results we can conclude that the intestinal nematodes are more widespread than is generally assumed and therefore represent a health problem for dogs and cats in the territory of Banja Luka. [ABSTRACT FROM AUTHOR]

Despite many advantages of e-commerce for both firms and buyers, it is still not equally adopted by customers in all European Union countries. According to Digital Scoreboard in countries such as United Kingdom and Denmark, nearly 90% of Internet users shop online. On the other hand, in Romania and Bulgaria, not even one-third of the Internet users buy goods and services online. Diffusion of e-shopping clearly has different pace across EU. In this article, we focus on individuals who refuse to purchase over Internet and aim to explore reasons for their behavior. To do so, we rely on Community Statistics on Information Society (CSIS) microdata for the year 2015. Individuals who report ordering and buying over the Internet more than one year ago and those who never engaged in online shopping were asked about reasons for not buying online. Potential reasons include lack of skills, privacy and security concerns, delivery concerns and problems, not having payment cards as well as habit, loyalty and preference of shopping in stores. The focus of this article is on comparison of reasons for not shopping online of individuals in EU countries that lead in adoption of e-shopping with laggard countries. We first analyze the prevalence of reasons for not buying online and compare countries in that respect. Among individuals who did not adopt e-shopping, there are those who have tried it at one point in time and did not continue to use it frequently and those who actually never engaged in buying over Internet. Both have certain reasons and constrains that prevent them from adopting this form of shopping. The analysis is followed by identification of reasons that significantly affect probability of trying online shopping, if not adopting it fully. It can be assumed that gaining true experience might contribute to increase in adoption of e-shopping among individuals. This is even more important for countries that still lag behind not just in buying online but in overall digital performance. [ABSTRACT FROM AUTHOR]

The paper addresses the question of human capital as constraint to innovation in post-transition economies. The analysis is performed both on the macroeconomic and microeconomic levels. Macroeconomic level encompasses discussion of available human capital and clustering of post-transition economies accordingly. Microeconomic analysis based on the Business Environment and Enterprise Performance Survey confirms that innovative firms are more likely to perceive inadequate education of the workforce as severe obstacle to their business activities. In all analyzed clusters, the more innovative employers feel compelled to train their employees, the more likely they are to be dissatisfied with the education of the workforce. [ABSTRACT FROM AUTHOR]

In this study, the focus was on the effects of sub-MICs of the antibiotics on adherence, hydrophobicity, and biofilm formation by two groups of Streptococcus pyogenes strains, which were responsible for different clinical cases. The aim of this study was to explore the effects of sub-MICs of penicillin, ceftriaxone, erythromycin, and clindamycin on adherence, surface hydrophobicity, and biofilm biomass in two selected collections of group A streptococcus (GAS): strains isolated from carriers (CA) and strains isolated from patients with tonsillopharyngitis (TPh). Isolates were tested for hydrophobicity to xylene, adherence, and biofilm production in uncoated microtiter plates before and after treatment with 1/2 and 1/4 MICs of antibiotics. Penicillin reduced adherence and biofilm production in TPh strains, whereas ceftriaxone diminished adherence and biofilm formation in CA group. On the contrary, clindamycin enhanced adherence and biofilm production in both groups of strains. Erythromycin did not significantly alter adherence, but triggered biofilm production in both groups of isolates. Hydrophobicity of both groups of strains was significantly reduced after exposure to all antibiotics. Beta-lactams displayed anti-biofilm activity; penicillin diminished both adherence and biofilm production in TPh strains, whereas ceftriaxone reduced it in strains isolated from CA. [ABSTRACT FROM AUTHOR]

The slow progress of innovation in transition economies is not related just to firms' decision to invest in innovation activities. Rather, it is worth distinguishing between their decision to increase investment, reduce it, keep their investments at the same level or not invest in innovation activities at all. To understand these decisions we develop and estimate models for post-transition and developed European countries employing multinomial probit. The analysis relies on responses of 2580 firms from 11 post-transition countries and 4058 firms from 18 European countries collected by the Flash Eurobarometer 433 - Innobarometer 2016 survey. We have established that the firms' decision making process in general is mostly related to previous innovation investment experience. In transition countries, the higher the percent of turnover invested in innovation, the lower the probability of an increase in the future. In the firms operating in developed economies, lower turnover from new products is related to the decision to decrease innovation investment in the future. [ABSTRACT FROM AUTHOR]

The aim of this article is to identify innovation barriers that limit innovation performance of small and medium enterprises (SME) in Croatia. Data are obtained using an online survey. The sample consists of 94 SMEs that have experience in innovation activities. The impact of constraints to innovation is measured on five-point scale. Employing the factor analysis, we reduced number of variables to four factors. Cluster analysis is used to group SMEs according to factors that constrain their innovation activities. SMEs are grouped into three clusters. Results reveal that firms are mostly constrained by external factors. In two out of three clusters, firms report high intensity of financial constraints to their innovation activity. The findings reveal that the least pronounced constraints to innovation in SMEs in Croatia are organisational constraints. [ABSTRACT FROM PUBLISHER]

Post-transition countries struggle in their attempt to catch-up the more advanced market economies with more or less success. Simultaneously, the business performance of the countries whose innovation indicators lag behind the desired levels seems relatively poor. Often emphasized problems in post-transition countries regard the relations of fi rms with government institutions. We analyze perceptions of innovative and non-innovative fi rms in dealing with government officials, aiming to explore if these two groups of fi rms share similar experiences with tax administration, business licensing and courts officials. The analysis is focused on 17 European post-transition countries that are either EU members or accession countries. The results reveal that corrected for selection mechanism, innovative fi rms do not perceive courts as an obstacle to their business activities more than non-innovative fi rms, although they seem to participate more in court-related procedures. Furthermore, innovative fi rms in these countries are more likely to perceive licensing and tax administration as obstacles to their business. Thus, specific policy measures aimed at creating positive business environment should be designed in order to enhance innovation activities and support long-term growth prospects. [ABSTRACT FROM AUTHOR]

Head and neck cancers (HNC) are a heterogeneous group of diseases. Histopathological, these are head and neck squamous cell carcinoma (HNSCC) epithelium of the skin, mucosa of the upper aerodigestive tract, pharynx and larynx. HNSCC is the fifth leading cause of cancer worldwide. The most important risk factors are alcohol and smoking. In the recent years, the studies have been conducted in order to prove the role of HPV in HNSCC carcinogenesis. The prevalence of HPV in HNSCC is 30%. HPV is often detected in biological materials of males. People with HPV positive HNSCC respond better to treatment and have a better treatment outcome than patients with no proven HPV. In the future, HPV should be the marker that will influence the choice of therapy in patients with HNSCC, but also the factor that will indicate the outcome of this malignancy in the human population. [ABSTRACT FROM AUTHOR]

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In order to develop an innovation, enterprises can collaborate either with academic institutions or other enterprises that would profit from its development. Collaboration is determined by various factors. The goal of this paper is to determine variables that are predictors of innovation collaboration in Croatian enterprises. The results of discriminant analysis suggest that the variables distinguishing between the group of companies that collaborate and those that do not collaborate are: lack of qualified personnel, number of radical innovation, investment in R&D, number of employees and market orientation. Variables used in the analysis that do not contribute to discrimination between the groups include the number of incremental innovations, too high costs related to innovation activities and a lack of appropriate financial resources. [ABSTRACT FROM AUTHOR]