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Nontuberculous mycobacteria (NTM) have emerged as an important cause of opportunistic nosocomial infections. NTM has frequently been isolated from hospital water distribution systems. The aim of this study was to survey the risk of NTM infections and determine the prevalence of NTM species in the hospital water distribution systems in Tabriz, Iran. One hundred and twenty samples of water from different sources of Tabriz hospitals were collected. The samples were filtered through 0.45-µm pore size membranes and decontaminated with 0.01% cetylpyridinium chloride. The sediment was inoculated onto Lowenstein-Jensen medium and incubated for 8 weeks. For identification to the species level, partial sequence analysis of the hsp65 and 16S rRNA genes were used. NTM were detected in 76 (63.3%) of 120 samples. Potentially pathogenic mycobacteria and saprophytic mycobacteria were isolated. Mycobacterium gordonae was the only single species that was present in all types of water. The prevalence of NTM in Tabriz hospitals' water compared with many investigations on hospital waters was high. This indicates that the immunocompromised patients and transplant recipients are at risk of contamination which necessitates considering decontamination of water sources to prevent such potential hazards.

Introduction: Salmonella is known as one of the most important causes of gastrointestinal disease in the world. Quinolones and fluoroquinolones are used successfully in the treatment of salmonellosis particularly for infections that have become resistant to several antibiotics. But non-susceptible isolates to quinolones have been reported in several countries. The data are limited about the prevalence of quinolone-resistant isolates in our country. Therefore, this study investigated the plasmid-mediated quinolone resistance genes in Salmonella enterica isolated in Children's Medical Center in Tehran during 2014-2015.Methods and Materials: Salmonella isolates were isolated and identified using standard microbiological methods. Antibiotic susceptibility testing and screening of Salmonella strains resistant to quinolones were performed according to the CLSI guidelines. The molecular investigation was done using specific primers for detection of qnr genes including: qnrA, qnrB and qnrS, by polymerase chain reaction.Results:Overall, 92 (66.6%) strains were resistant to nalidixic acid. None of the strains showed resistance to ciprofloxacin. Out of the 92 nalidixic acid resistant strains, 52 (56.52%) harbored qnrS genes, 15 strains (16.30%) had both qnrA and qnrS genes. Two (1.1%) isolates were positive for qnrB gene. Twenty four (26.08%) nalidixic acid resistant isolates did not have any qnr qens.Conclusion:The results of this study show high prevalence of resistance to nalidixic and qnr genes in Salmonella isolates. Plasmid nature of this type of resistance poses an increased risk of dissemination of quinolone resistance between Salmonella and non-Salmonella isolates circulating in hospitals environments.

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The propolis produced by bees is used by them to protect their hives. The cavity inside the hive’s walls is filled in during cold days to reduce entry points and mummify any intruders to ensure their survival. A current focus in nanotechnology and nanoscience is the green biosynthesis of nanoparticles (NPs) using biomaterials. Research on green methods for making metal oxide NPs is gaining momentum to safeguard the environment from the potential dangers associated with toxic chemicals. This study aimed to synthesize copper NPs (CuNPs) via propolis extraction, a novel application of nanoscience. The study was conducted under a range of pH, time conditions, and concentration ratios, and its properties were characterized by UV-Vis absorption spectra, XRD, and FTIR. An FTIR analysis revealed that compounds found in propolis extract could have an effect on the surface modification of the synthesized NPs. The propolis (Khalkhal) extract spectrum exhibited a sharp peak at 3422 cm−1, caused by free hydroxyl groups and their intra/intermolecular hydrogen bonds. There were sharp peaks at 2925, 1637, and 1515 to 1076 cm−1 associated with the C = O and C = C aromatic stretching frequencies. According to UV-Vis spectrophotometry investigation, CuO NPs exhibit a characteristic peak at 385 nm, showing significant surface plasmon resonance (SPR) with propolis (Khalkhal) extract. Furthermore, specific wavelengths of CuO NPs demonstrate peaks at 243, 292, and 350 nm for propolis (Gilan) extract. The green synthesis of CuNPs from Gilan and Khalkhal propolis can be an appropriate candidate for clinical applications such as drug delivery systems, drug formulation, and biomedical applications.

Bacillus species isolated from honeybee Apis mellifera gut, honey and bee bread samples were characterized for their in vitro probiotic and safety attributes. Alpha and γ haemolytic cultures were tested for their antibiotic resistance, antibacterial spectrum, acid and bile tolerance, adhesion ability (auto‐aggregation, co‐aggregation and hydrophobicity) and phenol tolerance. Safety criteria included evaluation of virulence genes and cytotoxicity percentages. Bacillus isolates inhibited both Gram‐positive and Gram‐negative pathogens including Staphylococcus aureus, Pseudomonas aeruginosa, Enterococcus faecalis and Streptococcus mutans, while none could inhibit Listeria monocytogenes. Among the isolates, Bacillus subtilis ZH05, ZB03 and ZG025 showed resistance to most of the tested antibiotics and were considered unsafe. B. subtilis (4) and B. licheniformis (1) tolerated acidic pH and bile conditions, never the less were more tolerant in simulated intestinal conditions vis‐a‐vis gastric conditions. In 0·5% phenol concentrations, B. licheniformis ZH02 showed highest growth, while, B. subtilis ZG029 demonstrated highest auto‐aggregation (65 ± 4·6) and hydrophobicity (23 ± 3·6) percentages (P < 0·05). The isolates lacked virulence genes (hblA, hblC, hblD, nhe, cytK and ces), and their cytotoxic percentage on Caco‐2 cell lines was ˂15%. Overall, honeybees appear to be a good source of Bacillus species exhibiting typical in vitro probiotic properties, which could be of commercial interest.