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The study reports an effluent-free, green process for the production of materials with favorable antibiofilm properties by cellulose acetate grafting with quaternary ammonium compounds in supercritical carbon dioxide. Two quaternary ammonium compounds, N-(2-Hydroxyethyl)-N,N-dimethylundecan-1-aminium Bromide and N-(11-Hydroxyundecanyl-N,N-dimethyltetradecan- 1-aminium Bromide, were synthesized and chemically attached to cellulose acetate via hexamethylene diisocyanate as a linker under the conditions of 30 MPa and 70 °C. The polymer modification occurred in its whole volume. The chemical conversion led to a decrease in the degree of crystallinity and the appearance of a rugged polymer surface. However, the cross-section imaging of the newly obtained materials revealed a compact polymer structure. The functionalized materials acquired hydrophobic properties. Microbiological tests showed the impossibility of Staphylococcus aureus ATCC 29213, Methicillin-resistant Staphylococcus aureus ATCC 43300, Escherichia coli ATCC 10536, and Salmonella Enteritidis ATCC 13076 attachment to the material obtained by the cellulose acetate grafting procedure with N-(11-Hydroxyundecanyl-N,N-dimethyltetradecan- 1-aminium Bromide.

It has long been known that coronaviruses cause various infectious diseases in animals. Although SARS-CoV-2 is genetically related to viruses isolated from Rhinolophus bats, the exact origin, mode of transmission, and how the human species has become the epidemiological reservoir of the virus have not yet been established with certainty. Although the main route of transmission is human-to-human, there are considerable numbers of reported cases of infection in animal species, predominantly among pet animals. The aim of this retrospective study was to assess SARS-CoV-2 seropositivity in dogs and cats during the COVID-19 pandemic in Šumadija District, Serbia. We used serology to identify household contacts of pet animals with infected pet owners and the degree of association. The study presented in this paper is also the first study of this type in Serbia. The results of a retrospective serosurvey, which was conducted in dogs and cats with different exposure risk factors, were analyzed to find the possible modes of transmission between humans and animals. The relative frequency of SARS-CoV-2 infection in dogs was 1.45% bounded with a 95% confidence interval (CI) of 0.0007–7.73%, while in cats, it was 5.56% (95% CI: 0.77–4.13%). The relative frequency of SARS-CoV-2 infection in pet owners was 11% (95% CI: 6.25–18.63%). In pets that were in close contact with COVID-19 positive owners, the seropositivity was found to be 9%. Out of a total of five stray dogs and cats tested, seropositivity was observed in two animals. Detected SARS-CoV-2 infection in pets shows that these animals are susceptible to infection and that the most common means of virus transmission to pets is through contact with diseased owners. However, the presence of infection in stray dogs and cats is not clear and needs further research.

There is an urgency to develop novel materials capable of preventing the adherence of microorganisms to their surface. Such materials with antibiofilm properties are needed in hospitals and public places, animal farms and veterinary hospitals, and biofouling prevention. Biofouling is the phenomenon of adhesion and the growth of microorganisms on surfaces in contact with water. It poses a significant problem for filtration processes, water treatment units, bioreactors, and ships performance (marine biofouling). High-pressure techniques such as supercritical solvent impregnation and grafting in the supercritical phase allow for the modification of a solid matrix throughout the whole volume and production of materials of unique properties in an environmentally friendly way. Grafting involves the chemical attachment of an active compound to a solid matrix, ensuring its long-lasting properties. Grafting in supercritical carbon dioxide (scCO2) has been reported as an efficient tool in the production of materials with antibacterial1 , and recently also antibiofilm properties2 . This study aims to investigate the potential of cellulose acetate (CA) grafting with quaternary ammonium compounds (QAC) for acquiring antibiofilm properties. Two QAC were synthesized, and the grafting conditions were investigated. The grafting was performed via hexamethylene diisocyanate (HDI) as a linker1 . Obtained materials were analyzed using FTIR, SEM and Ion microscopy, DSC analyses, contact angle measurements, and standardized microbiological procedures to evaluate antibiofilm properties.

In September 2018, a four-month-old dog with fever and petechial bleeding came to the internal clinic at the Faculty of Veterinary Medicine University of Belgrade. On hematology analysis, thrombocytopenia and mild anemia were observed. Examination of the blood smear revealed platelet inclusions. The commercial serology test was positive for Anaplasma spp. The dog was treated with doxycycline for 14 days, and after 48 hours from the beginning of the treatment, the symptoms subsided. PCR analysis and sequencing confirmed infection with A. platys., U septembru 2018. godine, štene staro četiri meseca, sa znacima groznice i petehijalnim krvarenjem, je došlo u ambulantu Klinike za male životinje Fakulteta veterinarske medicine Univerziteta u Beogradu. Hematološka analiza je pokazala trombocitopeniju i blagu anemiju. Pregledom krvnog razmaza ustanovljene su inkluzije u trombocitima. Komercijalni serološki test je pokazao prisustvo antitela protiv Anaplasma spp. Sprovedena je terapija doksiciklinom u trajanju od 14 dana, a posle 48 sati od početka terapije znaci bolesti su se povukli. PCR analizom i senkvencioniranjem je potvrđeno prisustvo Anaplasma platys.

Simple Summary:& nbsp;West Nile fever is an arthropod-borne viral disease that is transmitted from birds to humans and animals by mosquitoes. Humans may develop a severe disease, which sometimes can be fatal. At the end of the 20th century, the first outbreaks of West Nile fever among humans in urban environments in Eastern Europe and the United States were reported. The epidemics were characterized by the neurological form of the disease with a fatal outcome. Since the first outbreak of the disease in Serbia, the highest number of cases occurred in 2018. West Nile fever spread is driven by location and time, which means nearby locations and periods have similar features. Recognition of patterns of spread of the disease has the potential to facilitate the mosquito control program and disease prevention. This study aimed to examine the geographical and temporal similarities of registered cases during the epidemics in the period 2017-2019 in South Banat District, Serbia. We identified the following factors as crucial for the prediction of possible outbreaks: the presence of virus in natural reservoirs, mosquito abundance; precipitation, high water level of rivers followed by a consequent sudden decrease of precipitation and withdrawal of rivers into the main bed, and favorable temperatures. LT /p> LT br> LT /p> West Nile virus (WNV) is an arthropod-born pathogen, which is transmitted from wild birds through mosquitoes to humans and animals. At the end of the 20th century, the first West Nile fever (WNF) outbreaks among humans in urban environments in Eastern Europe and the United States were reported. The disease continued to spread to other parts of the continents. In Serbia, the largest number of WNV-infected people was recorded in 2018. This research used spatial statistics to identify clusters of WNV infection in humans and animals in South Banat County, Serbia. The occurrence of WNV infection and risk factors were analyzed using a negative binomial regression mod

The aim of the present study was to characterize Enterobacterales resistant to 3rd and 4th generation cephalosporins, carbapenems and/or fluoroquinolones, isolated from dogs and cats with urogenital infections. In total, 36 strains (Escherichia coli (n = 28), Klebsiella pneumoniae (n = 3), Serratia marcescens, Raoultella ornithinolytica, Proteus mirabilis, Citrobacter portucalensis and Enterobacter cloacae (each n = 1)) were included in the present study, 28 from Austria and 8 from Serbia. Isolates were characterized by a polyphasic approach including susceptibility pheno-and genotyping and microarray-based assays. Escherichia (E.) coli isolates were additionally characterized by two-locus (fumC and fimH) sequence phylotyping and multi-locus sequence typing (MLST) of selected isolates. MLST of carbapenem-resistant Enterobacter cloacae isolates was also performed. Among E. coli, the most dominant phylogenetic group was B1 (27.8%), followed by C, (16.6%), A and Clade II (5.5% each), B2 and F (2.77% each). The most predominant β-lactam resistance genes were blaTEM (70%) and blaCTX-M (38.8%), blaCMY (25%). blaNDM was detected in one carbapenem-resistant Enterobacter cloacae ST114. The most common ST among selected E. coli was 744 (10.7% isolates). The pandemic clones ST131 and ST648 carrying CTX-M-15 were also detected. Remaining STs belonged to 469, 1287, 1463 and 1642. E. coli clonotyping revealed 20 CH types. Based on the presence of certain virulence genes, three isolates were categorized as ExPEC/UPEC. The most prevalent virulence factors were fimH detected in 61%, iucD and iss both in 55%, iroN in 27.8%, papC in 13.8% and sat in 8.3% isolates.

In the present study, supercritical solvent impregnation (SSI) has been applied to incorporate thymol into bio-composite polymers as a potential active packaging material. Thymol, a natural component with a proven antimicrobial activity, was successfully impregnated into starch-chitosan (SC) and starch-chitosan-zeolite (SCZ) films using supercritical carbon dioxide (scCO2) as a solvent. Experiments were performed at 35 °C, pressures of 15.5 and 30 MPa, and an impregnation time in the range of 4–24 h. The highest impregnation yields of SC films with starch to chitosan mass ratios of 1:1 and 1:2 were 10.80% and 6.48%, respectively. The addition of natural zeolite (15–60%) significantly increased the loading capacity of films enabling thymol incorporation in a quantity of 16.7–27.3%. FTIR and SEM analyses were applied for the characterization of the films. Mechanical properties and water vapor permeability of films before and after the impregnation were tested as well. Thymol release kinetics in deionized water was followed and modeled by the Korsmeyer-Peppas and Weibull model. SCZ films with thymol loading of approximately 24% exhibited strong antibacterial activity against E. coli and methicillin-resistant Staphylococcus (S.) aureus (MRSA).

A novel impregnation process for the fabrication of cotton nanocomposite with strong antimicrobial activity against antibiotics-resistant bacteria and yeast was developed. The impregnation process includes the sol-gel treatment of fabric with (3-aminopropyl)triethoxysilane in the first step, and synthesis of the CuO/Cu2O nanoparticles (NPs) on the fabric surface in the second step. The in situ synthesis of the CuO/Cu2O NPs was based on the adsorption of Cu2+-ions by the introduced amino groups of the sol-gel coating. The adsorbed Cu2+-ions are subsequently reduced in the alkaline solution of NaBH4. X-ray diffraction measurements confirmed the formation of CuO/Cu2O NPs. Scanning electron microscopy and atomic absorption spectrometry analyses indicate that the particle size, agglomeration, and amounts of synthesized NPs were highly affected by the initial concentration of CuSO(4)solution. The toxicity of nanocomposites to human keratinocytes (HaCaT) and antimicrobial activity against Gram-negativeEscherichia coliATCC 25922,E. coliATCC BAA 2469, andKlebsiella pneumoniaeATCC BAA 2146, and Gram-positive bacteriaStaphylococcus aureusATCC 25923,S. aureusATCC 43300 and yeastCandida albicansATCC 24433 strongly depended on the copper content. In addition to excellent antimicrobial activity, controlled release of Cu2+-ions from the fabrics into physiological saline solution was obtained.

Supercritical fluid extraction as an environmentally friendly technology was applied to isolate biologically active extracts from celery and parsley fruits for potential applications in the food industry. The extractions were performed under mild temperature conditions of 39.85 °C and at pressures of 10 and 30 MPa. The extracts were analyzed regarding their chemical composition, antibacterial activity, and cytotoxic effect. Sedanolide was the dominant component of the celery fruit extracts, comprising more than 70% of the obtained fraction, while the content of apiole in the parsley fruit SC CO2 extracts exceeded 85%. The celery fruit extracts showed strong and moderately strong antibacterial activity against tested Staphylococcus aureus, Bacillus (B.) cereus, B. subtilis, B. circulans, Listeria (L.) greyi, L. seeligeri and L. welshimeri, with minimal inhibitory concentration (MIC) values between 160 and 640 µg/mL, and weak activity against the selected Salmonella isolates with a MIC of 2560 µg/mL. The parsley extract obtained at 10 MPa showed strong and moderately strong antibacterial effects against Bacillus strains with obtained MICs of 160-640 µg/mL, and weak activity against Staphylococcus, Listeria, and Salmonella with a MIC of 2560 µg/mL. Cytotoxicity investigation showed that the extracts with proven antibacterial activity had no cytotoxic effect on rabbit kidney cells at concentrations of up to 640 µg/mL.

A novel impregnation process for the fabrication of cotton nanocomposite with strong antimicrobial activity against antibiotics-resistant bacteria and yeast was developed. The impregnation process includes the sol–gel treatment of fabric with (3-aminopropyl)triethoxysilane in the first step, and synthesis of the CuO/Cu2O nanoparticles (NPs) on the fabric surface in the second step. The in situ synthesis of the CuO/Cu2O NPs was based on the adsorption of Cu2+-ions by the introduced amino groups of the sol–gel coating. The adsorbed Cu2+-ions are subsequently reduced in the alkaline solution of NaBH4. X-ray diffraction measurements confirmed the formation of CuO/Cu2O NPs. Scanning electron microscopy and atomic absorption spectrometry analyses indicate that the particle size, agglomeration, and amounts of synthesized NPs were highly affected by the initial concentration of CuSO4 solution. The toxicity of nanocomposites to human keratinocytes (HaCaT) and antimicrobial activity against Gram-negative Escherichia coli ATCC 25922, E. coli ATCC BAA 2469, and Klebsiella pneumoniae ATCC BAA 2146, and Gram-positive bacteria Staphylococcus aureus ATCC 25923, S. aureus ATCC 43300 and yeast Candida albicans ATCC 24433 strongly depended on the copper content. In addition to excellent antimicrobial activity, controlled release of Cu2+-ions from the fabrics into physiological saline solution was obtained.

Nosema ceranae je микроспоридијa којa паразитира код Европске медоносне пчеле, Apis mellifera, и доминантна је врста рода Nosema у југоисточној Европи. У зависности од степена инфекције и периода године, овај ендопаразит може имати далекосежне последице по пчеле, њихово здравље и продуктивност. Последњих година посебно је истраживан утицај N. ceranae на имунитет пчела а закључци појединих истраживања издвајају ефекат супресије гена значајних за имунитет пчела, односно доказују имуносупресивне последице инфекције врстом N. ceranae. Терапија ноземозе подразумева употребу антибиотика фумагилина, који има доказану ефикасност у сузбијању инфекције али његови споредни ефекти могу представљати проблем за саме пчеле и квалитет пчелињих производа, те је стога је његова примена у многим земљама ограничена. Имајући ово на уму константно се трага за природним и синтетским компонентама које би биле замена за фумагилин. Тестиране су многе супстанце, а међу онима које су показале најбољи ефекат издвајају се екстракти биљака и алги и синтетске витаминско-минералне мешавине. У овом раду је у кавезном експерименту тестирано пет препарата: (1) антибиотик фумагилин, (2) биљни екстракт тимол; и три адитива у исхрани пчела: (3) комерцијални препарат Beewell AminoPlus који представља витаминско-аминокиселинску мешавину, (4) комерцијални препарат Medenko forte који садржи екстракте храстове коре, пелена и жалфије и (5) полисахаридни екстракт гљиве Agaricus blazei. Пчеле су у свим третираним групама трећег дана живота инфициране спорама N. ceranae, а различите групе су третиране препаратима од првог, трећег и шестог дана. Код третираних пчела је праћен ефекат на преживљавање пчела, степен Nosema инфекције, нивое експресије гена значајних за имунитет пчела (абецин, дефензин, хименоптецин, апидецин и вителогенин) и ниво оксидативног стреса праћен кроз активност антиоксидативних ензима (каталазе, супероксид дизмутазе и глутатион С-трансферазе) и концентрације малондиалдехида..., Apis mellifera, and the dominant Nosema species in Southeast Europe. Depending on the infection level it could have significant consequences on bees, their health and productivity. The impact of N. ceranae on honey bees’ immunity has been particularly investigated in recent years. Some conclusions of this research underline N. ceranae-induced suppression of immune-related genes, proving its immunosuppressive impact. Treatment for nosemosis includes the use of the antibiotic fumagillin. Fumagillin has proven effect in Nosema control, but its side effects may pose a problem for the bees and the quality of their products, which is why its application in many countries have been limited. Hence, researchers are constantly looking for natural and synthetic components which could be suitable substitutes for fumagillin. Many products have been tested and plant/algae extracts and synthetic vitamin-mineral complexes showed the best effects. This laboratory (cage) experiment included testing of five products: (1) antibiotic fumagillin (2) a plant extract - thymol, and three dietary supplements: (3) a commercial amino acid and vitamin complex named Beewell AminoPlus, (4) a commercial mixture of oak bark, sage and absinth extracts named Medenko forte, and (5) a polysaccharide extract of Agaricus blazei mushroom. Bees in all treatment groups were infected with N. ceranae spores on day 3, and treated with the listed products from day 1, 3 or 6 after emergence. Bee survival, Nosema loads, levels of immune-related genes (abaecin, apidaecin, hymenoptaecin, defensin and vitellogenin) expression and the level of oxidative stress, assessed through the activity of antioxidative enzymes (catalase, glutathione S-transferase and superoxide dismutase) and the concentration of malondialdehyde, were measured in all experimental groups. The obtained values were compared with those of control (noninfected and infected) groups...

U ovoj doktorskoj disertaciji ispitano je prisustvo uzročnika kju groznice - bakterije Coxiella burnetii (C. burnetii) kod nevlasničkih pasa poreklom sa teritorije grada Beograda, primenom molekularnih i seroloških metoda. Molekularni metod je korišćen za otkrivanje uzročnika u reproduktivnim tkivima nevlasničkih pasa, kao i u krpeljima prisutnim na ispitivanim životinjama, dok je imunoenzimskim testom utvrđeno prisustvo specifičnog serološkog odgovora kod ispitivanih životinja. Za otkrivanje prisustva DNK C. burnetii u uzrocima korišćena je lančana reakcija polimeraze (Trans-PCR) kojom se umnožava IS1111 fragment C. burnetii, dok je za otkrivanje specifičnih antitela protiv C. burnetii u serumima ispitivanih pasa korišćen modifikovani komercijalni imunoenzimski test (ELISA). U istraživanju je sakupljeno 316 krpelja sa 51 nevlasničkog psa i identifikovane su tri vrste krpelja: Rhipicephalus sanguineus, Ixodes ricinus i Dermacentor reticulatus. Prisustvo DNK C. burnetii ustanovljeno je u 10,53% (24/228) krpelja vrste R. sanguineus, koji su uzorkovani sa sedam pasa. Reproduktivna tkiva pasa sakupljena su od ukupno 105 pasa - 74 ženke (70,48%) i 31 mužjaka (29,52%). DNK C. burentii je ustanovljena kod 20,95% (22/105) pasa i to u 16,13% (5/31) uzoraka semenika pasa, odnosno u 22,97% (17/74) uzoraka materica i jajnika. Kod 29,52% (31/105) pasa je 5 ustanovljeno prisustvo specifičnih antitela protiv C. burnetii i to 32,26% (10/31) mužjaka i 28,38% (21/74) ispitanih ženki..., In this doctoral dissertation, the presence of the causative agent of Q fever - the bacterium Coxiella burnetii (C. burnetii) in stray dogs has been examined using molecular and serological methods. Molecular method was used for the detection of the agent in the reproductive tissues of stray dogs, as well as in the ticks recovered from the examined animals, while immunoenzyme test was used for the detection of specific serological response in the examined animals. A polymerase chain reaction (Trans-PCR) targeting IS1111 element of C. burnetii was used for the detection of C. burnetii DNA in the samples, while a modified commercial immunoassay (ELISA) was used for the detection of specific antibodies against C. burnetii in the sera of the examined dogs. In this study, 316 ticks were recovered from 51 stray dogs and three tick species were identified: Rhipicephalus sanguineus, Ixodes ricinus and Dermacentor reticulatus. The presence of C. burnetii DNA was established in 10.53% (228/24) R. sanguineus ticks, which originated from seven dogs. Reproductive tissues of dogs were collected from a total of 105 dogs - 74 females (70.48%) and 31 males (29.52%). The presence of C. burentii DNA has been detected in 20.95% (22/105) dogs. C. burnetii DNA was detected in 7 16.13% (5/31) samples of dog testicles and in 22.97% (17/74) samples of uteri and ovaries...

U ovoj doktorskoj disertaciji je ispitana mogućnost primene simpleks i multipleks PCR protokola sa prethodno opisanim prajmerima za preciznu identifikaciju najčešće izolovanih serovarijeteta Salmonella vrsta na teritoriji Vojvodine. Takođe je ispitana efikasnost primene metode sekvenciranja gena za 16Ѕ rRNK u preciznoj identifikaciji salmonela. Ispitano je 107 izolata Salmonella enterica ssp. enterica identifikovanih klasičnom serotipizacijom kao: Infantis (52), Enteritidis (33), Tenessee (5), Mbandaka (4), Montevideo (3), Havana (2), Lille (2), Senftenberg (2), Typhimurium (1), Agona (1), Derby (1) i Livingstone (1). Korišćena je tripleks PCR reakcija u detekciji bcfC, steB i sdf lokusa, optimizovana tokom preliminarnih ispitivanja. Primenom tripleks PCR, samo S. Enteritidis je mogla precizno da bude razlikovana od drugih serovarijeteta, dok su ostali serovarijeteti na osnovu rezultata tripleks PCR svrstavani u dve grupe (Grupa 1 i Grupa2). S. Infantis, najzastupljeniji serovarijetet među ispitanim izolatima nije mogao biti precizno identifikovan jer se primenom tripleks PCR nije razlikovao od ostalih članova Grupe 2. Za njegovu konačnu identifikaciju je primenjen simpleks PCR za umnožavanje segmenta fljB koji je karakterističan samo za S. Infantis. Sekvenciranje gena za 16Ѕ rRNK je primenjeno u identifikaciji izolata devet različitih serovarijeteta. Poredjenjem rezultata dobijenih u klasičnoj serotipizaciji i u PCR, uočeno je slaganje u 91 slučaju od ukupno 107 (85%). Od 33 izolata S. Enteritidis njih 31 (94%) je dao očekivan PCR profil. U slučaju S. Infantis PCR je potvrdila identifikaciju u samo 75% (39 od 52) slučajeva. Ostali ispitani serovarijeteti dali su očekivane PCR profile. Sekvenciranje gena za 16Ѕ rRNK je bilo pouzdano samo u određivanju pripadnosti ispitanih izolata rodu Salmonella., Aim of this doctoral thesis was to test the applicability of published primers for the identification of serovars isolated most frequently in the north part of our country using multiplex and simplex PCR reactions. The efficacy of sequencing of gene for 16S ribosomal RNA for identification of Salmonella strains was also checked. The study was conducted on 107 serotyped Salmonella enterica ssp. enterica isolates. Strains belonged to the following serovars: Infantis (52), Enteritidis (33), Tenessee (5), Mbandaka (4), Montevideo (3), Havana (2), Lille (2), Senftenberg (2), Typhimurium (1), Agona (1), Derby (1) i Livingstone (1). A triplex PCR protocol (bcfC, steB, sdf) optimized during preliminary investigations was used. This reaction separated S. Enteritidis from other strains, while the remaining serovars divided in two distinct groups (Group 1 and Group 2). As the used PCR protocol could not differentiate S. Infantis, the most numerous serovar among isolates, from other members of the Group 2, its identification was completed using a simplex PCR reaction targeting fljB specific for S. Infantis. Comparison of the results of serotyping and PCR protocols revealed a concordance in 91 cases from the total of 107 (85%). From 33 strains serotyped as S. Enteritidis 31 (94%) had the predicted PCR profile. Regarding S. Infantis, identification based on genomic markers confirmed this serovar only in 75% of cases (39 from 52). Other serovars showed their typical PCR profiles. Sequencing of gene for 16S ribosomal RNA could reliably determine only that tested isolates are the members of the genus Salmonella

The presence of the methicillin resistance gene mecC in coagulase-negative Staphylococcus spp. (CoNS) is scarce. The aim of this study was to characterize mecC-positive CoNS isolated from various wild and domestic animals. The presence of the mecC gene was screened in 4299 samples from wild animals and domestic animals. Fifteen coagulase-negative staphylococci, that displayed a cefoxitin-resistant phenotype, were tested mecC-positive by PCR. Antimicrobial susceptibility testing was performed for all isolates. The 15 isolates were genotyped by sequencing of the entire class E mec gene complex (blaZ-mecC-mecRI-mecI), the ccrA and ccrB recombinase genes and other determinants within the type XI SCCmec element. DNA microarray analysis was performed and five selected isolates were additionally whole genome sequenced and analyzed. S. stepanovicii (n = 3), S. caprae (n = 1), S. warneri (n = 1), S. xylosus (n = 1) and S. sciuri (n = 9) were detected. All but the S. sciuri isolates were found to be susceptible to all non-beta lactams. The entire class E mec gene complex was detected in all isolates but ccrA and ccrB genes were not identified in S. stepanovicii and S. xylosus. The genes erm(B) and fexA (n = 4, each) were the most predominant non-beta lactam resistance genes detected in the S. sciuri isolates. Even though the presence of the mecC gene among CoNS is a rare observation, this study further expands our knowledge by showing that the mecC gene, including its allotypes, are present in more staphylococcal species from different animal species than has been previously described.

Two new nitrato complexes of zinc and nickel with 1,4,8,11-tetrakis(2-pyridylmethyl)-1,4,8,11-tetraazacyclotetradecane (tpmc), have been synthesized and characterized. The IR spectral peaks showed that the coordinated and ionic nitrate ions are in agreement with the formula proposed by elemental analysis. Conductometric titrations predicted methanol to be a convenient solvent for synthesis and revealed the stoichiometry of the complexes, while molar electrical conductivities indicated a 1 : 3 complex electrolyte type for the zinc complex, and a 1 : 2 complex electrolyte type for the nickel complex. The optimized complex structure was obtained by molecular modeling and density functional theory calculations. The biological activity of the novel complexes was examined by screening eight different bacterial strains and two cancer cell lines. The zinc complex showed better antimicrobial activity against the bacterial strains, while the complexes did not show significance antiproliferative activity toward cancer cells MCF-7 and MDA-MB-231.

This study discusses the possibility of in situ synthesis of Cu-based nanoparticles (NPs) on cotton and viscose rayon fabrics previously modified with 1,2,3,4-butanetetracarboxylic acid (BTCA) of different concentrations, with the aim to obtain antibacterial protection. The changes in the chemical structure of the fibers caused by the modification with BTCA were assessed by FTIR spectroscopy. The higher the concentration of the applied BTCA, the larger the amounts of free carboxyl groups in both fabrics. AAS analysis showed that the samples modified with higher concentration of BTCA provided larger Cu2+-ions uptake and consequently, higher content of Cu after Cu2+-ions reduction. The presence of Cu-based NPs on the fabrics was confirmed by FESEM and EDS analyses. XRD analysis revealed that NPs appeared as a mixture of CuO and Cu2O. Synthesized NPs imparted excellent antibacterial activity to both fabrics against E. coli and S. aureus, including methicillin-resistant S. aureus.

This study discusses the possibility of fabrication of textile nanocomposites with antimicrobial activity against antibiotics-resistant bacterial strains and yeast. Modification of cotton fabric with oxalic acid solutions of different concentrations provided free carboxyl groups for binding of Cu2+ -ions from copper (II) sulfate solution which were further reduced with sodium borohydride in alkaline solution. An increase in the concentration of applied oxalic acid resulted in larger amounts of free carboxyl groups on the cotton fibers, Cu2+ -ions uptake and total amounts of Cu-based nanoparticles after reduction. XPS and XRD analyses suggested that nanoparticles mainly consisted of CuO with fractions of Cu2O. Fabricated textile nanocomposites ensured maximum reduction of Gram-negative E. coli ATCC 25922, E. coli NCTC 13846, E. coli ATCC BAA-2469, K. pneumoniae ATCC-BAA 2146 and P. aeruginosa ATCC 27853, Gram-positive bacteria S. aureus ATCC 25923 and S. aureus ATCC 43300 and yeast C. albicans ATCC 24433. Additionally, controlled release of Cu2+ -ions from fabrics into the physiological saline solution was obtained within 24 hours.

The aim of this study was to characterize a collection of methicillin-resistant Staphylococcus aureus (MRSA) isolates of human and animal origin from Serbia. In total, 36 MRSA isolates-30 obtained from humans and six from companion animals-were investigated by PCR for the presence of antibiotic and biocide resistance determinants and virulence genes (PVL-Panton-Valentine leukocidin, ETs-exfoliative toxins, TSST-toxic shock syndrome toxin, SEs-staphylococcal enterotoxins, and MSCRAMMs-microbial surface components recognizing adhesive matrix molecules and biofilm). Isolates were analyzed by staphylococcal cassette chromosome mec (SCCmec), spa, and dru typing, as well as by multiple locus variable number of tandem repeat analyses (MLVA), multilocus sequence typing (MLST), and subsequently, eBURST. The majority of human MRSA isolates were resistant to gentamicin, erythromycin, clindamycin, and ciprofloxacin. Different antibiotic resistance genes were detected: aac-aphD, ant(6 )-Ia, erm(A), erm(B), erm(C), tet(K), tet(M), fexA, and cat(pC221). All isolates were susceptible to teicoplanin and linezolid. SCCmec type III was prevalent in human isolates, while SCCmec elements in animals were mostly nontypeable. t037 was the predominant spa type in human and t242 in animal MRSA isolates. The prevalent dru type was dt11c in human and dt10a in animal MRSA isolates. MRSA isolates exhibited 27 different MLVA types. ST239 was predominant in human, while ST5 was prevalent in canine MRSA isolates. PVL was found in two, while tsst-1 was detected in three human isolates. Human-associated clones belonging to ST5, ST45, and ST239 MRSA clones were discovered in companion animals, which suggests anthropozoonotic transmission.

Nosema ceranae is a microsporidian endoparasite of the European honey bee, Apis mellifera, and the dominant Nosema species in Southeast Europe. Depending on the infection level it could have significant consequences on bees, their health and productivity. The impact of N. ceranae on honey bees’ immunity has been particularly investigated in recent years. Some conclusions of this research underline N. ceranae-induced suppression of immune-related genes, proving its immunosuppressive impact. Treatment for nosemosis includes the use of the antibiotic fumagillin. Fumagillin has proven effect in Nosema control, but its side effects may pose a problem for the bees and the quality of their products, which is why its application in many countries have been limited. Hence, researchers are constantly looking for natural and synthetic components which could be suitable substitutes for fumagillin. Many products have been tested and plant/algae extracts and synthetic vitamin-mineral complexes showed the best effects. This laboratory (cage) experiment included testing of five products: (1) antibiotic fumagillin (2) a plant extract - thymol, and three dietary supplements: (3) a commercial amino acid and vitamin complex named Beewell AminoPlus, (4) a commercial mixture of oak bark, sage and absinth extracts named Medenko forte, and (5) a polysaccharide extract of Agaricus blazei mushroom. Bees in all treatment groups were infected with N. ceranae spores on day 3, and treated with the listed products from day 1, 3 or 6 after emergence. Bee survival, Nosema loads, levels of immune-related genes (abaecin, apidaecin, hymenoptaecin, defensin and vitellogenin) expression and the level of oxidative stress, assessed through the activity of antioxidative enzymes (catalase, glutathione S-transferase and superoxide dismutase) and the concentration of malondialdehyde, were measured in all experimental groups. The obtained values were compared with those of control (noninfected and infected) gr, Nosema ceranae je mikrosporidija koja parazitira kod Evropske medonosne pčele, Apis mellifera, i dominantna je vrsta roda Nosema u jugoistočnoj Evropi. U zavisnosti od stepena infekcije i perioda godine, ovaj endoparazit može imati dalekosežne posledice po pčele, njihovo zdravlje i produktivnost. Poslednjih godina posebno je istraživan uticaj N. ceranae na imunitet pčela a zaključci pojedinih istraživanja izdvajaju efekat supresije gena značajnih za imunitet pčela, odnosno dokazuju imunosupresivne posledice infekcije vrstom N. ceranae. Terapija nozemoze podrazumeva upotrebu antibiotika fumagilina, koji ima dokazanu efikasnost u suzbijanju infekcije ali njegovi sporedni efekti mogu predstavljati problem za same pčele i kvalitet pčelinjih proizvoda, te je stoga je njegova primena u mnogim zemljama ograničena. Imajući ovo na umu konstantno se traga za prirodnim i sintetskim komponentama koje bi bile zamena za fumagilin. Testirane su mnoge supstance, a među onima koje su pokazale najbolji efekat izdvajaju se ekstrakti biljaka i algi i sintetske vitaminsko-mineralne mešavine. U ovom radu je u kaveznom eksperimentu testirano pet preparata: (1) antibiotik fumagilin, (2) biljni ekstrakt timol; i tri aditiva u ishrani pčela: (3) komercijalni preparat Beewell AminoPlus koji predstavlja vitaminsko-aminokiselinsku mešavinu, (4) komercijalni preparat Medenko forte koji sadrži ekstrakte hrastove kore, pelena i žalfije i (5) polisaharidni ekstrakt gljive Agaricus blazei. Pčele su u svim tretiranim grupama trećeg dana života inficirane sporama N. ceranae, a različite grupe su tretirane preparatima od prvog, trećeg i šestog dana. Kod tretiranih pčela je praćen efekat na preživljavanje pčela, stepen Nosema infekcije, nivoe ekspresije gena značajnih za imunitet pčela (abecin, defenzin, himenoptecin, apidecin i vitelogenin) i nivo oksidativnog stresa praćen kroz aktivnost antioksidativnih enzima (katalaze, superoksid dizmutaze i glutation S-transferaze) i koncentracije malondialdehida.

A total of 61 honey bees from different regions of the Republic of Serbia were analyzed for Clostridium botulinum (C. botulinum) spores. The microbiological methods and molecular methods (multiplex PCR/mPCR and PCR method) were utilized to examine multiple subunits of each honey bees samples. The C. botulinum spores in PCR-positive samples were estimated by the most probable number method (MPN). The presence of C. botulinum spores, by applying mPCR and PCR methods, was detected in 1 of the 61 honey bees (1.64%). Using MPN method, the number of spores in positive sample was 110/kg. Detection of C. botulinum spores directly from untreated honey bees, without prior enrichment, is impossible by applying PCR. Using conventional microbiological methods, detection of C. botulinum spores in dead honey bees is not possible without preenrichment. Therefore, conventional, microbiological methods are not suitable for the detection of C. botulinum spores in honey bees. In order to detect C. botulinum spores in honey bees using PCR methods, due to the small and/or unequal distribution of spores in the samples, it is desirable to use multiple subunits/replicates for each sample examined.

Two new nitrato complexes of zinc and nickel with 1,4,8,11-tetrakis(2-pyridylmethyl)-1,4,8,11-tetraazacyclotetradecane (tpmc), have been synthesized and characterized. The IR spectral peaks showed that the coordinated and ionic nitrate ions are in agreement with the formula proposed by elemental analysis. Conductometric titrations predicted methanol to be a convenient solvent for synthesis and revealed the stoichiometry of the complexes, while molar electrical conductivities indicated a 1 : 3 complex electrolyte type for the zinc complex, and a 1 : 2 complex electrolyte type for the nickel complex. The optimized complex structure was obtained by molecular modeling and density functional theory calculations. The biological activity of the novel complexes was examined by screening eight different bacterial strains and two cancer cell lines. The zinc complex showed better antimicrobial activity against the bacterial strains, while the complexes did not show significance antiproliferative activity toward cancer cells MCF-7 and MDA-MB-231.

In this doctoral dissertation, the presence of the causative agent of Q fever - the bacterium Coxiella burnetii (C. burnetii) in stray dogs has been examined using molecular and serological methods. Molecular method was used for the detection of the agent in the reproductive tissues of stray dogs, as well as in the ticks recovered from the examined animals, while immunoenzyme test was used for the detection of specific serological response in the examined animals. A polymerase chain reaction (Trans-PCR) targeting IS1111 element of C. burnetii was used for the detection of C. burnetii DNA in the samples, while a modified commercial immunoassay (ELISA) was used for the detection of specific antibodies against C. burnetii in the sera of the examined dogs. In this study, 316 ticks were recovered from 51 stray dogs and three tick species were identified: Rhipicephalus sanguineus, Ixodes ricinus and Dermacentor reticulatus. The presence of C. burnetii DNA was established in 10.53% (228/24) R. sanguineus ticks, which originated from seven dogs. Reproductive tissues of dogs were collected from a total of 105 dogs - 74 females (70.48%) and 31 males (29.52%). The presence of C. burentii DNA has been detected in 20.95% (22/105) dogs. C. burnetii DNA was detected in 7 16.13% (5/31) samples of dog testicles and in 22.97% (17/74) samples of uteri and ovaries..., U ovoj doktorskoj disertaciji ispitano je prisustvo uzročnika kju groznice - bakterije Coxiella burnetii (C. burnetii) kod nevlasničkih pasa poreklom sa teritorije grada Beograda, primenom molekularnih i seroloških metoda. Molekularni metod je korišćen za otkrivanje uzročnika u reproduktivnim tkivima nevlasničkih pasa, kao i u krpeljima prisutnim na ispitivanim životinjama, dok je imunoenzimskim testom utvrđeno prisustvo specifičnog serološkog odgovora kod ispitivanih životinja. Za otkrivanje prisustva DNK C. burnetii u uzrocima korišćena je lančana reakcija polimeraze (Trans-PCR) kojom se umnožava IS1111 fragment C. burnetii, dok je za otkrivanje specifičnih antitela protiv C. burnetii u serumima ispitivanih pasa korišćen modifikovani komercijalni imunoenzimski test (ELISA). U istraživanju je sakupljeno 316 krpelja sa 51 nevlasničkog psa i identifikovane su tri vrste krpelja: Rhipicephalus sanguineus, Ixodes ricinus i Dermacentor reticulatus. Prisustvo DNK C. burnetii ustanovljeno je u 10,53% (24/228) krpelja vrste R. sanguineus, koji su uzorkovani sa sedam pasa. Reproduktivna tkiva pasa sakupljena su od ukupno 105 pasa - 74 ženke (70,48%) i 31 mužjaka (29,52%). DNK C. burentii je ustanovljena kod 20,95% (22/105) pasa i to u 16,13% (5/31) uzoraka semenika pasa, odnosno u 22,97% (17/74) uzoraka materica i jajnika. Kod 29,52% (31/105) pasa je 5 ustanovljeno prisustvo specifičnih antitela protiv C. burnetii i to 32,26% (10/31) mužjaka i 28,38% (21/74) ispitanih ženki...

Šiga toksin produkujuće Escherichia coli (STEC) čine jednu od šest grupa dijarejagenih E. coli. Na svjetskom nivou, infekcija izazvana STEC najčešći je uzrok akutne renalne insuficijencije kod djece i starijih osoba. Kako su psi prepoznati kao rezervoari STEC, blizak kontakt ljudi i pasa predstavlja rizik za zoonotsku transmisiju ovih bakterija. U Republici Srbiji, osim ograničenog broja istraživanja o prisustvu STEC kod domaćih životinja i ljudi nema dostupnih literaturnih podataka o istraživanjima ove grupe E. coli kod pasa. Stoga, cilj ove doktorske disertacije bio je da se dokaže prisustvo i utvrdi prevalencija STEC u populaciji pasa s teritorije grada Novog Sada, izvrši tipizacija i molekulrna karakterizacija sojeva E. coli izolovanih iz fecesa pasa i utvrdi prisustvo rezistentnih sojeva E. coli. U ovo istraživanje bio je uključen 101 pas s teritorije Novog Sada, a kao materijal korišćeni su uzorci fecesa pasa. U cilju izolacije E. coli iz fecesa pasa primijenjeni su standardni bakteriološki metodi izolacije i biohemijske identifikacije, a potvrda pripadnosti vrsti izvršena je korišćenjem matricom potpomognute laserske desorpcije/jonizacije-vrijeme preleta masene spektrometrije (MALDI-TOF MS). Za utvrđivanje prisustva STEC kod pasa primijenjeni su metodi lateks aglutinacije za serogrupu O157, direktne aglutinacije za serogrupe “velike šestorke” O26, O45, O103, O111, O121 i O145, test verocitotoksičnosti (VCA), imunoenzimski test (ELISA), kao i lančana reakcija polimeraze (PCR). Antibiotska rezistencija utvrđena je disk difuzionim metodom prema standardima EUCAST i CLSI. U ovom istraživanju, po prvi put u Republici Srbiji, dokazano je prisustvo STEC u populaciji pasa. Primjenom VCA metoda ustanovljena je prevalencija od 1,98%, dok je primjenom ELISA i PCR metoda ustanovljena prevalencija od 5,94% odnosno 4,95%. Dva izolata E. coli pripadala su nekoj od serogrupa “velike šestorke” STEC, dok prisustvo sojeva iz serogrupe O157 nije utvrđeno. U ispitivanoj popul, Shiga toxin-producing Escherichia coli (STEC) strains constitute one of six groups of diarrheagenic E. coli. Infection caused by STEC is the most common cause of acute renal failure in young children and elderly people worldwide. As dogs are recognized as a reservoir for STEC, the close contact between humans and dogs poses a risk for zoonotic transmission of these bacteria. Except scarce studies of STEC in humans and domestic animals, there are no available data about this E. coli group in dogs in the Republic of Serbia. Therefore the aim of this doctoral dissertation was to determine the presence and prevalence of STEC in the dog populaton in the area of Novi Sad, to perform typing and molecular characterization of E. coli strains isolated from faeces of dogs, as well to determine the presence of antibiotic resistant E. coli strains. In total 101 dogs from the area of Novi Sad was included in this research. As the material fecal samples of dogs were used. In order to isolate E. coli strains from faeces standard methods of bacterial isolation and biochemical identification were used, and for the confirmation of species identity matrix-assisted laser desorption/ionization time-offlight mass spectrometry (MALDI-TOF MS) was used. In order to determine the presence of STEC in dogs latex agglutination for the serogroup O157, direct agglutination for “big six” serogroups (O26, O45, O103, O111, O121 and O145), Vero cell cytotoxicity assay (VCA), enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR) were used. Antibiotic resistance was determined by disc diffusion method according to the EUCAST and CLSI guidelines. In this research, for the first time in the Republic of Serbia, the presence of STEC has been proven in the dog population. By VCA method the prevalence of 1,98% was determined, while by ELISA and PCR the determined prevalence was 5,94% and 4,95% respectively. Two E. coli isolates belonged to some of the STEC “big six” serogroups, while

Pseudomonas aeruginosa je ubikvitaran, oportunistički patogen, uzročnik infekcija kod životinja i ljudi, koje su najčešće povezane sa kompromitovanim imunološkim sistemom domaćina. Patogeneza pseudomonasne infekcije je multifaktorijalan proces koji uključuje produkciju faktora virulencije vezanih za ćeliju, odnosno faktora virulencije koji se sekretuju, složenu međubakterijsku komunikaciju putem četiri sistema, kao i sposobnost prelaska iz planktonske životne forme u formu biofilma. Značaj ove vrste za medicinu i veterinu potvrdila je Svetska zdravstvena organizacija u izveštaju objavljenom 2017. godine, po kom P. aeruginosa pripada kritičnoj grupi bakterijskih vrsta za koje je potrebno hitno razviti nove terapeutike jer, zbog sve učestalije pojave multirezistentnih sojeva, ova vrsta predstavlja ozbiljnu pretnju javnom zdravlju. U okviru ove disertacije uporedno su analizirani faktori virulencije izolata P. aeruginosa izolovanih iz uzoraka obolelih životinja i ljudi, kao što su sposobnost formiranja biofilma (ukupan biofilm i biofilm na granici vazduh-tečnost), proizvodnja piocijanina, hemolitička aktivnost, sposobnost manifestovanja tri tipa pokretljivosti (plivanje, rojenje i grčenje), kao i citotoksični efekat na ćelijama iz ćelijske linije A549. Filogenetska srodnost i grupisanje odabranih izolata P. aeruginosa proučavana je na osnovu parcijalne sekvence gena za 16S rRNK. Ispitivanje postojanja korelacija između odabranih faktora virulencije urađeno je primenom robusne rang korelacije. Grupisanje izolata je izvedeno metodom hijerarhijske klasterizacije na osnovu euklidske udaljenosti normalizovane vrednostima sedam ispitivanih faktora virulencije i citotoksičnosti. Metodom mašinskog učenja konstruisan je prediktivni model na osnovu koga je određena značajnost ispitivanih faktora virulencije u predviđanju citotoksičnog potencijala izolata P. aeruginosa. Ispitivanje razlika između faktora virulencije izolata različitog porekla (izolati poreklom od ljudi u odnosu n

Bruceloza pasa je bolest poznata preko četiri decenije, ali i pored toga ne postoje standardizovani dijagnostički protokoli, kao ni generalni dogovor o najprikladnijem dijagnostičkom testu. Svaka laboratorija definiše sopstvene kriterijume. Ovakva raznovrsnost testova i nedostatak jasno definisanih protokola dovodi do teškoća u interpretaciji rezultata seroloških testova u različitim laboratorijama. Iz tog razloga, cilj ove doktorske disertacije obuhvatio je unapređenje dijagnostike primenom preporučenih i novih, sopstveno pripremljenih testova. Jedan od zadataka ove disertacije je bilo i ispitivanje upotrebljivosti Bruce-ladder multiplex PCR metode za ispitivanje kliničkih uzoraka odnosno tkiva uterusa i testisa pasa. Sakupljen je materijal (krv, testisi i materice) od 225 nevlasničkih pasa i to 145 ženki i 80 mužjaka. Dobijeni rezultati su pokazali da je od ukupno 225 ispitanih uzoraka, 33 ili 14,67% krvnih seruma imalo merljiv titar antitela u 2-ME TAT. Najniži ispitivani titar od 1/50 imalo je 13 krvnih seruma ili 5,78%, kod 8 krvnih seruma ustanovljen je titar od 1/100 ili 3,55%, dok je titar od 1/200 imalo 12 uzoraka seruma ili 5,33%. Primenom klasičnih bakterioloških metoda, B. canis je izolovana iz tri uzorka homogenizata tkiva reproduktivnih organa (1,33%) i to iz 2 uzorka poreklom od mužjaka i jednog uzorka poreklom od ženke. Jedan izolat je poticao od serološki negativnog psa. Od 225 uzoraka ispitanih Bruce-ladder multiplex PCR metodom, pozitivna reakcija je ustanovljena kod dva (0,88%). Pre formulacije indirektnog ELISA testa, određivane su koncentracije proteina. Elektroforetska analiza antigena dobijenih toplotom i ultrazvukom kao i denzitometrijska kvantifikacija su pokazale da je u antigenu dobijenom toplotom, najzastupljenija frakcija molekulske mase 10,95 kDa sa učešćem od čak 43,12% koja odgovara R-LPS-u brucela. Ista frakcija je u antigenu dobijenom ultrazvukom bila zastupljena sa 11,56%, odnosno u količini koja je bila 3,7x manja..., The scientific community has known about canine brucellosis for over four decades, even so, there are no standardized diagnostic protocols, nor a general agreement on the most appropriate diagnostic test. Each laboratory defines its own criteria. This variety of tests and the lack of clearly defined protocols lead to difficulties in interpreting the results of serological tests in different laboratories. For this reason, the goal of this doctoral dissertation has been to improve diagnostics using recommended and new, self-prepared tests. One of the tasks of this dissertation was to examine the usability of the Bruce-ladder multiplex PCR method for testing clinical samples, i.e. dog uterine and testicular tissues. The material (blood, testicles and uteruses) was collected from 225 dogs without owners, 145 female and 80 male dogs. The results obtained showed that from a total of 225 tested samples, 33 or 14,67% of blood sera had measurable antibody titer in 2-ME TAT. 13 or 5,78% blood sera had the lowest tested titer of 1/50, in 8 or 3,55% blood sera a titer of 1/100 was determined, while 12 serum samples or 5,33% had the titer of 1/200. By applying classic bacteriological methods, B. canis was isolated from three samples of homogenized reproductive organ tissue (1,33%), 2 from samples originating from males and one specimen originating from a female. One isolate originated from a serologically negative dog. Of the 225 samples assayed using the Bruce-ladder multiplex PCR method, a positive reaction was established in two (0,88%). Protein concentrations were determined prior to the formulation of the indirect ELISA test. The electrophoretic analysis of antigens retrieved using heat and ultrasound, as well as the densitometric quantification, showed that the antigen retrieved using heat had the most prevalent molecular weight fraction of 10,95 kDa with a participation of as much as 43,12% that corresponds to Brucella R LPS. The same fraction was represented in the antig

This study discusses utilization of supercritical carbon dioxide for impregnation of cellulose acetate films with thymol in order to produce material with anti-biofilm activity against Pseudomonas aeruginosa and Staphylococcus aureus. Analysis of anti-biofilm activity of cellulose acetate beads impregnated with thymol suggested that optimal thymol loading was in the range from 26% to 30% for efficient reduction of biofilm formation and eradication of pre-formed biofilms. Polymer films were fabricated by the solvent casting method from polymer solutions of different contents, and loaded with thymol using supercritical carbon dioxide at 15.5 MPa and 35 degrees C. The film containing 30% of thymol (F1 30%) exhibited substantial anti-adhesion properties inhibiting biofilm formation on its surface and considerably reduced formation of biofilms on the surrounding surfaces (up to 80%) by all tested strains including antibiotic resistant P. aeruginosa DM50 and methicillin-resistant S. aureus.