Antibiotic Resistance and Probiotics: Knowledge Gaps, Market Overview and Preliminary Screening.

Probiotics are among those products, the use of which is increasing, and they are available primarily as food/dietary supplements, as well as in the form of medicines. This study aims to assess the attitudes and practices of health professionals and students of health sciences, give a short overview of the probiotics currently on the market, and conduct a screening of five food supplements and one drug with respect to antibiotic resistance. Nearly half of the respondents in our survey state that probiotics have no side effects, while only 6.3% believe that the use of probiotics can lead to antibiotic resistance. In addition, more than 40% of the participants throw unused probiotics into municipal waste. The market analysis results indicate that probiotic products on the Serbian market have highly variable CFU counts, while the declared health claims cover numerous beneficial health effects, and they are sometimes even registered as medicines. Lactobacilli are frequently present in probiotic supplements, and are sold in pharmacies and online. The experimental results showed that antibiotic resistance is present in different types of lactobacilli in probiotic products. The risk of using probiotics, regardless of their beneficial health effects, should be taken into account in the future. An update to the regulations governing probiotics, including a stipulation for antimicrobial resistance (AMR) testing, should be established, and guidelines for their proper use and disposal put into place.

E6/E7 mRNA Expression of the Most Prevalent High-Risk HPV Genotypes in Cervical Samples from Serbian Women.

Cervical cancer caused by persistent infection with HR HPV genotypes is the second leading cause of death in women aged 15 to 44 in Serbia. The expression of the E6 and E7 HPV oncogenes is considered as a promising biomarker in diagnosing high-grade squamous intraepithelial lesions (HSIL). This study aimed to evaluate HPV mRNA and DNA tests, compare the results according to the severity of the lesions, and assess the predictive potential for the diagnosis of HSIL. Cervical specimens were obtained at the Department of Gynecology, Community Health Centre Novi Sad, Serbia, and the Oncology Institute of Vojvodina, Serbia, during 2017-2021. The 365 samples were collected using the ThinPrep Pap test. The cytology slides were evaluated according to the Bethesda 2014 System. Using a real-time PCR test, HPV DNA was detected and genotyped, while the RT-PCR proved the presence of E6 and E7 mRNA. The most common genotypes in Serbian women are HPV 16, 31, 33, and 51. Oncogenic activity was demonstrated in 67% of HPV-positive women. A comparison of the HPV DNA and mRNA tests to assess the progression of cervical intraepithelial lesions indicated that higher specificity (89.1%) and positive predictive value (69.8-78.7%) were expressed by the E6/E7 mRNA test, while higher sensitivity was recorded when using the HPV DNA test (67.6-88%). The results determine the higher probability of detecting HPV infection by 7% provided by the mRNA test. The detected E6/E7 mRNA HR HPVs have a predictive potential in assessing the diagnosis of HSIL. The oncogenic activity of HPV 16 and age were the risk factors with the strongest predictive values for the development of HSIL.

Vibrio metschnikovii isolated from cosmetic products as potential cause of skin infection.

Cosmetics intended for human use should be free of microbes involving a potential health hazard. Different points in the cosmetic production process, from the choice of raw materials and the formulation itself to the final packaging, can be critical. The aim of this study is to present the first case of Vibrio metschnikovii isolated from cosmetics in Serbia, which caused signs of skin infection. Standard microbiological examination of the cosmetic sample, as well as skin swabs from the skin changes which appeared after applying the same cosmetics, were taken with final identification to the level of species applying matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry. Adequate management of hazard analysis and critical control points in cosmetic production is strongly recommended, which would guarantee microbiological safety of the final product.

First Isolation of Exiguobacterium aurantiacum in Serbia.

Exiguobacterium aurantiacum is isolated from a variety of environmental samples but rarely from patients. The aim of the study was to represent isolation of unusual bacterial strains that could cause infection in patients. Final identification was performed using matrix-assisted description/ionization time-of-flight mass spectrometry (MALDI-TOF). Two isolates strains of E. aurantiacum were isolated, one isolate from distilled water used during surgical treatment and the second one from a patient with bacteremia after radical prostatectomy, both sensitive to all tested antimicrobials. Environmental strains could cause infection, especially in immunocompromised patients; therefore, rare bacteria testing is required, in which identification special assistance is provided by an automated system MALDI-TOF.

Molecular evaluation of chronic restrain stress in mice model of non metastatic fibrosarcoma.

Chronic stress is regarded as a significant factor in the etiology of the many diseases. Numerous methods have been developed through which the effect of chronic stress is examined. The aim of this study is to demonstrate the new experimental model for analysis of immuno-suppression induced by chronic restraint stress, through challenge with conditionally tumorigenic cell line BHK-21/C13. 20 male NMRI mice were randomly divided into 2 groups-control and experimental. Each mouse was subcutaneously inoculated with BHK-21/C13 cells. Stress in the experimental group was induced for 20 days. After the experiment, tumor masses were removed, and analyzed using histology and immunohistochemistry techniques. We found a statistically significant difference (p = 0.034) in tumor expression and tumor volumes (p = 0.0061) between groups, as well as in immunopositivity on Ki67, cytochrome C and matrix metalloproteinase 9. Absence of immune infiltrate was noticed in experimental, and the presence of inflammatory infiltrate at tumor invasion front in control group.

Biogenic amine and microbiological profile of Serbian dry fermented sausages of artisanal and industrial origin and associated health risk.

From the public health point of view, safety of dry fermented sausages is of concern due to possible presence of biogenic amines and some other food hazards. Taking into consideration that biogenic amines are chemical indicators of microbiological contamination, industrial and artisanal dry fermented sausages produced in Serbia were subjected to the microbiological and biogenic amine profiling. Microorganisms identified by MALDI-TOF MS included Cronobacter sakazakii and Listeria innocua, whereas the food pathogens were not detected. Biogenic amine content, determined by HPLC method in the range from 37.3 to 1186 mg/kg, was characterised as very low to low in 40% of the samples, moderate in 38%, high in 14% and very high in 8%. Risk assessment revealed that consumption of dry fermented sausages could cause histamine and tyramine intake up to 11.9% and 3.4% of threshold dose for healthy population, respectively. Adverse health effects would be rather unlikely for general population.

[Frequency of vancomycin-resistant enterococci isolated from blood cultures from 2008 to 2010].

INTRODUCTION: Enterococci are important hospital-acquired pathogens. The most commonly isolated species of the genus, Enterococcus faecalis and Enterococcus faecium are the third to fourth-most prevalent nosocomial pathogens worldwide. The aim of this study was to determine the frequency of resistance to vancomycin and other antimicrobial agents of Enterococcus spp strains isolated from blood cultures of hospitalized patients. MATERIAL AND METHODS: During the three-year period, from 2008 to 2010, 132 strains of Enterococcus spp isolated from blood cultures of hospitalized patients were tested for their susceptibility to ampicillin, vancomycin, gentamycin (high-level resistance), erythromycin, chloramphenicol, teicoplanin, ciprofloxacin by disc diffusion method according to the Clinical and Laboratory Standards Institute recommendations. Susceptibility of vancomycin resistant E. faecium to the same antibiotics and to linezolid, quinopristin/dalfopristin and tigecyclin was determined using VITEK system. RESULTS AND DISCUSSION: Resistance to vancomycin was detected in 21 (15.9%) Enterococcus spp strains. The percentage of resistance to other antimicrobial agents varied from 23. l% for chloramphenicol to 81.3% for ciproflxacin. All vancomycin resistant enterococci were identified as E. faecium and belonged to phenotype VanA. The resistance to other antibiotics was very high, except for linezolid and quinopristin/dalfopristin (4.7%). The high-level aminoglycoside resistance was 87.6% for gentamycin and 95.2% for streptomycin. All isolates were resistant to ampicillin, teicoplanin and ciprofloxacin. CONCLUSION: The detected high frequency of multidrug-resistant isolates among vancomycin resistant enterococci is of great importance and suggests the need for further monitoring of susceptibility in order to take adequate measures to prevent and control spreading of resistant strains.

Resistance of Escherichia coli from healthy donors and from food--an indicator of antimicrobial resistance level in the population.

Escherichia coli, being an important part of normal intestinal flora, is a frequent carrier of antimicrobial drug resistance markers and food is the most important vector of antimicrobial resistance genes between humans and animals. The aim of this study was to confirm the presence and frequency of resistance markers in Escherichia coli from intestinal flora and from food as an indicator of antimicrobial resistance level in the population. The experiment included 100 fecal Escherichia coli isolates from healthy donors, 50 isolated in 2007 and 50 in 2010, and 50 from food samples. The resistance markers were found in all groups of isolates. The resistance to ampicillin and cotrimoxazole was most commonly found. The finding of multi-drug-resistant strains and resistance to ciprofloxacin is important. The frequency of resistance markers was similar in food and feces. The results of this study show the need to introduce systematic monitoring of antimicrobial resistance of these bacteria.

[Carbapenems resistance of Acinetobacter spp strains isolated from wound swabs during 2009-2010].

INTRODUCTION: Acinetobacter spp has become an important cause of nosocomial infections due to its great ability to survive and spread in a hospital setting and to develop resistance to many antibiotics. The aim of this study was to examine the resistance to carbapenems and other commonly used antibiotics in strains of Acinetobacter isolated from wound swabs. MATERIAL AND METHODS: In the Laboratories of Microbiology Center at the Institute for Public Health in Novi Sad wound swabs were taken from the patients hospitalized at the Institutes and Departments of the Clinical Center of Vojvodina in Novi Sad. A total of 271 Acinetobacter spp strains were tested to susceptibility on carbapenems and other most commonly used antibiotics by disk diffusion method according to the recommendation of the Clinical and Laboratory Standards Institute. RESULTS AND DISCUSSION: Acinetobacter spp (271 isolates) developed resistance to imipenem and meropenem (67.4% and 64.4%). The resistance to both cephalosporins III and IV generation and ciprofloxacin was 100%. The resistance to ampicillin-sulbactam was 71.4%. CONCLUSION: Our results show high resistance to carbapenems in Acinetobacter spp strains isolated from wound swabs. These facts suggest the need for continuous monitoring of susceptibility in order to take adequate measures to prevent and control spreading of resistant strains.

How a routine checking of Escherichia coli in retailed food of animal origin can protect consumers against exposition to Campylobacter spp. and Listeria monocytogenes?

BACKGROUND/AIM: According to the literature that has been published over the last two decades Campylobacter spp i Listeria monocitogens can be identified as causes of numerous diseases derived by consuming food of animal origin. The purpose of this paper was to find out how established national microbiological criteria of the Republic of Serbia on food safety in retailed food of animal origin could contribute to consumer's protection against exposition to foodborne pathogens such as Campylobacter spp. and Listeria monocytogenes. METHODS: During a routine microbiological safety control of randomly selected 60 samples of fresh poultry meat, 30 samples of other fresh meat readymade for grilling, 30 samples of sausage products, 37 samples of heat-treated meat, 39 samples of toppings for fast food of animal origin and 31 samples of dairy products a national food safety criteria (Escherichia coli, aerobic plate count, Salmonella spp., coagulasa positive Staphylococcus, Proteus spp., sulphito-reducting Clostridia) were applied and, as well as, testing to Campylobacter spp. and Listeria monocitogens. In determination of Campylobacter spp. and Listeria monocytogenes, food quality control methods of the Food and Agriculture Organization (FAO) were applied, while in determination of the other above motioned bacteria, national provisions on microbiological methods were applied who are adjusted to the FAO ones. RESULTS: Related to the national criteria on microbiological food safety, 88 (38.8%) samples, out of the total 227 tested, were rejected. When to these results, the results of laboratory tests on Listeria monocytogens were added, a terminal number of rejected samples were not changed. When to these results, the results of Campylobacter spp. testing were added, 91 (40.1%) out of the 227 samples were unsatisfied. Results of logistic regression model with occurrence of Escherichia coli as dependent variable indicated that Escherichia coli was 4.5 times likely to occur among samples with Campylobacter spp. than among samples without Campylobacter spp. (OR = 4.515, 95% CI: 1.019-20.002). Sensitivity of the fitted model (Hosmer-Lemeshowp = 0.268) was 76.8% and its specificity was 75.0%. At the same time Escherichia coli was confound in all (100%) food samples that were contaminated by Listeria monocytogenes. CONCLUSION: Statistical analysis indicated that Escherichia coli was completely sensitive to identify all samples contaminated with Listeria monocytogenas and highly sensitive to identify samples contaminated with Campylobacter spp. Nevertheless, 3 (1.3%) of the tested samples were not covered with Escherichia coli.