Carbapenemase-producing Klebsiella quasipneumoniae ST688 (NDM-1) and Klebsiella michiganensis ST40 (KPC-2) in food destined for hospitalized patients.

OBJECTIVES: Klebsiella spp. are leading causes of nosocomial infections. Their ability to harbour antimicrobial resistance genes makes them an important public health threat. This study aimed to report the genomic background of carbapenemase-producing Klebsiella quasipneumoniae (HV55B) and Klebsiella michiganensis (HV55D) strains isolated from fresh vegetables destined for hospitalized inpatients. METHODS: Microbiological and molecular methods were used to isolate and identify the strains, which were submitted to the antimicrobial susceptibility test and pH tolerance assays. Whole genome sequencing was performed on MiSeq and NextSeq platforms, and online available tools were applied to bioinformatic analysis of clinically relevant information. RESULTS: Both isolates were considered multidrug-resistant and tolerated pH ≥ 4 for 24 h. HV55B belonged to sequence type (ST) ST668, and presented a broad resistome and plasmids from four incompatibility groups. HV55D belonged to ST40. Both strains HV55B and HV55D were genetically close to isolates responsible for human infections around the world, which stands for the plausibility of such bacteria to cause disease in patients of the studied institution. CONCLUSIONS: Our results confirm the presence of carbapenemase-producing Klebsiella spp. in fresh foodstuffs intended for hospitalized inpatients' consumption. The genomes characterized here also provide clinically and genomically relevant information to forthcoming epidemiological surveillance studies.

Synthesis of thiazolidin-4-ones and thiazinan-4-ones from 1-(2-aminoethyl)pyrrolidine as acetylcholinesterase inhibitors.

The present study describes the synthesis of a novel series of thiazolidin-4-one and thiazinan-4-one using 1-(2-aminoethyl)pyrrolidine as amine precursor. All compounds were synthesised by one-pot three component cyclocondensation reaction from the amine, a substituted benzaldehyde and a mercaptocarboxylic acid. The compounds were obtained in moderate to good yields and were identified and characterised by 1H, 13 C, 2 D NMR and GC/MS techniques. The compounds also were screened for their in vitro acetylcholinesterase (AChE) activity in hippocampus and cerebral cortex on Wistar rats. The six most potent compounds have been investigated for their cytotoxicity by cell viability assay of astrocyte primary culture, an important cell of central nervous system. We highlighted two compounds (6a and 6k) that had the lowest IC50 in hippocampus (5.20 and 4.46 µM) and cerebral cortex (7.40 and 6.83 µM). These preliminary and important results could be considered a starting point for the development of new AChE inhibitory agents.