The comparison of SARS-CoV-2 antibody levels in medical personnel induced by different types of vaccines compared to the natural infection.

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.

Carbapenem-Resistant Acinetobacter baumannii: Biofilm-Associated Genes, Biofilm-Eradication Potential of Disinfectants, and Biofilm-Inhibitory Effects of Selenium Nanoparticles.

This study aimed to investigate the biofilm-production ability of carbapenem-resistant Acinetobacter baumannii (CRAB), the biofilm-eradication potential of 70% ethanol and 0.5% sodium hypochlorite, the effects of selenium nanoparticles (SeNPs) against planktonic and biofilm-embedded CRAB, and the relationship between biofilm production and bacterial genotypes. A total of 111 CRAB isolates were tested for antimicrobial susceptibility, biofilm formation, presence of the genes encoding carbapenemases, and biofilm-associated virulence factors. The antibiofilm effects of disinfectants and SeNPs against CRAB isolates were also tested. The vast majority of the tested isolates were biofilm producers (91.9%). The bap, ompA, and csuE genes were found in 57%, 70%, and 76% of the CRAB isolates, with the csuE being significantly more common among biofilm producers (78.6%) compared to non-biofilm-producing CRAB (25%). The tested disinfectants showed a better antibiofilm effect on moderate and strong biofilm producers than on weak producers (p < 0.01). The SeNPs showed an inhibitory effect against all tested planktonic (MIC range: 0.00015 to >1.25 mg/mL) and biofilm-embedded CRAB, with a minimum biofilm inhibitory concentration of less than 0.15 mg/mL for 90% of biofilm producers. In conclusion, SeNPs might be used as promising therapeutic and medical device coating agents, thus serving as an alternative approach for the prevention of biofilm-related infections.

Seroprevalence of SARS-CoV-2 antibodies among primary healthcare workers in the Republic of Srpska, Bosnia & Herzegovina: A cross-sectional study.

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.

Comparison of HPV detection rate in formalin-fixed paraffin-embedded tissues of head and neck carcinoma using two DNA extraction kits and three amplification methods.

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.

Influence of subinhibitory antibiotic concentration on Streptococcus pyogenes adherence and biofilm production.

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.

The Austrian Bone Marrow Donor Registry: Providing Patients in Austria with Unrelated Donors for Transplant - a Worldwide Cooperation.

BACKGROUND: The Austrian Bone Marrow Donor Registry is the central search coordinating unit in charge of national and international donor searches in Austria. PATIENTS AND METHODS: Between 1988 and 2010, a worldwide search for an unrelated donor of blood stem cells (URD) was initiated for 2,166 Austrian patients with haematological disorders, 1,671 adults and 495 children, by the Austrian Bone Marrow Donor Registry. RESULTS: An URD was identified for 78.3% of the patients between 2008 and 2010, for 76.7% of the patients between 2004 and 2007, for 71.3% between 1996 and 2003, but only for 53.4% of the patients in the initial period of 1988-1995. Thus, results of international donor searches improve over time. In contrast, search duration decreases steadily: Search times of successful searches decreased from about 8 months in the first period between 1988 and 1996 to 1.84 months in 2010. Overall, 1,558 of the 2,166 patients (71.9%) could be provided with a matching donor. However, not every patient provided with a URD was transplanted. Overall, only 1,141 of 2,166 patients (52.7%) proceeded to transplant. CONCLUSION: Figures have significantly improved for the latest period of donor searches between 2008 and 2010. In this period, a donor could be found for 78.3%, and 58.5% of the patients received a transplant.