Genetic Features of mcr-1 Mediated Colistin Resistance in CMY-2-Producing Escherichia coli From Romanian Poultry

© Copyright © 2019 Maciuca, Cummins, Cozma, Rimbu, Guguianu, Panzaru, Licker, Szekely, Flonta, Djordjevic and Timofte. Colistin is a last resort antibiotic used for the treatment of human infections associated with carbapenemase-producing Enterobacteriales. Here, we evaluated the occurrence of mcr-1 and -2 plasmid-mediated colistin resistance in colistin and/or carbapenem resistant human clinical Enterobacteriales and other gram-negative bacteria (n = 543) as well as third generation cephalosporin-resistant (3GCR) Escherichia coli isolates from poultry abattoir workers (n = 15) and poultry fecal samples (n = 92) collected from two geographically separate abattoirs in Romania. which revealed that mcr-1 was present within four sequence types (STs): ST744 (n = 7), ST57 (n = 7), ST156 (n = 2), and ST10 (n = 1). Within STs, serotypes were conserved and, notably, all except one of the mcr-1-positive isolates were found to exhibit fluoroquinolone-resistance (FQR) associated SNPs in both gyrA and parC. While there were variations in genotypes, all isolates belonging to ST744, ST57, and ST156 were rich in resistance determinants, carrying aminoglycoside-modifying enzymes genes, sulfonamide resistance gene blaTEM–1 as well as blaCMY–2 AmpC β-lactamase resistance genes. They also exhibited high similarity in carriage of virulence genes; ST10, however, only carried the mcr-1 gene. Whole genome sequencing (WGS) analysis also revealed that although the mcr-1 gene was identified in a diverse population of E. coli, two STs (ST57 and ST744) predominated and interestingly, were found in isolates across both abattoirs providing evidence for clonal transmission. Also, two main genomic contexts of mcr-1 isolates were revealed with all ST57 isolates harboring the mcr-1 gene between two copies of ISApl1 (or the Tn6330 transposon) whilst a common mcr-1 containing scaffold, highly similar to IncX type mcr-1-bearing plasmids (pWI2-mcr, Accession number: LT838201), was present among mcr-1 isolates of varying phylogenetic backgrounds (ST10, ST744 and ST156). The high prevalence of the mcr-1 gene in poultry E. coli isolates with co-resistance to cephalosporins and quinolones, in a country where antimicrobial use in food production species is poorly regulated, is concerning and the findings from this study should lead to better surveillance of antimicrobial resistance (AMR) in food-production animals in Romania

Facile and inexpensive fabrication of zinc oxide based bio-surfaces for C-reactive protein detection

© 2018, The Author(s). The paper reports a biosensor formed from antibody coated ZnO nano-crystals which has been prepared using a rapid and inexpensive fabrication method which utilises colloidal dispersion enhanced using sonication. This technique was used to prepare highly ordered and uniform nano-crystalline sensor surfaces on polyethylene terephthalate (PET) using 0.5%, 1% and 5% concentrations of zinc oxide nano-crystal suspensions. Impedance spectroscopy was employed to interrogate the sensor surfaces and confirmed high reproducibility of the fabrication process. Changes in impedance values, at a frequency of 138 Hz, were used to establish dose dependent responses for C-reactive protein (CRP) antigen. A limit of detection of less than 1 ng/ml was demonstrated fornano-surfaces fabricated from concentrations of 1% ZnO

Intraseasonal to interannual oscillations of Antarctic climate as recorded at Neumayer polar station

Possible oscillations in the Antarctic climate are investigated through statistical analysis of meteorological variables recorded at Neumayer polar station, located at Ekström Shelf Ice, Atka Bay, northeastWeddell Sea (7039’S,0815’W). Meteorological variables recorded at this station cover the period 1982 to 2011 with a 3 hours time resolution. At intraseasonal time scales spectral analysis reveals a strong diurnal cycle in the temperature and wind records. A wavelet analysis reveals that diurnal cycle is relatively strong (weak) during the warm (cold) Antarctic season. A persistent oscillation with a period of 35-40 days, with highest amplitude during the cold Antarctic season, was identified also in the temperature record. These oscillations dominate also intraseasonal variability of the wind record. Singular spectrum analysis reveals strong annual and semiannual cycles in the temperature and wind records. The amplitude of semiannual cycle shows decadal variations. Interannual variability of temperature record is dominated by a 5-6 year oscillation. A persistent cycle with a period of about 2 years was identified in the wind record. The origin of intraseasonal to interannual oscillations mentioned above are discussed in connection with the relevant modes of climate variability at these time scales: the Madden-Julian Oscillation, the Antarctic Oscillation, the Quasi-biennial Oscillation and the El Nino-Southern Oscillation. The seasonal variability in the strength of diurnal and 35-40 days cycles as well as decadal variability in the amplitude of semiannual and annual cycles are analyzed based both on internal and external forcing with focus on the role of the solar forcing. Possible implications of these results in the interpretation of climatic signal in the Antarctic ice cores are also presented

Daily to intraseasonal oscillations at Antarctic research station Neumayer

High temporal resolution (three hours) records of temperature, wind speed and sea level pressure recorded at Antarctic research station Neumayer (708S, 88W) during 1982–2011 are analysed to identify oscillations from daily to intraseasonal timescales. The diurnal cycle dominates the three-hourly time series of temperature during the Antarctic summer and is almost absent during winter. In contrast, the three-hourly time series of wind speed and sea level pressure show a weak diurnal cycle. The dominant pattern of the intraseasonal variability of these quantities, which captures the out-of-phase variation of temperature and wind speed with sea level pressure, shows enhanced variability at timescales of , 40 days and , 80 days, respectively. Correlation and composite analysis reveal that these oscillations may be related to tropical intraseasonal oscillations via large-scale eastward propagating atmospheric circulation wave-trains. The second pattern of intraseasonal variability, which captures in-phase variations of temperature, wind and sea level pressure, shows enhanced variability at timescales of , 35, , 60 and , 120 days. These oscillations are attributed to the Southern Annular Mode/Antarctic Oscillation (SAM/AAO) which shows enhanced variability at these timescales. We argue that intraseasonal oscillations of tropical climate and SAM/AAO are related to distinct patterns of climate variables measured at Neumayer