Saeedi, Z. | bioRxiv Science

bioRxiv2020

Cognitive resilience in bilinguals and its potentiality in dealing with cognitive load

Previous studies have demonstrated different patterns of results regarding cognitive benefits of bilingualism, ranging from bilingual advantage to no effect of bilingualism. This study examined the potential effect of bilingualism on cognitive resilience and performance. We recruited 21 Persian monolinguals and 19 Persian-English bilinguals. Color-Word Stroop task was used concurrently with verbal production tasks in order to produce three levels of task difficulty, i.e., doing the Stroop task while being silent (level 1), alphabet reciting (level 2), and counting odd numbers (level 3). We investigated the pattern of changes in Stroop task performance when faced with different difficulty levels Bilinguals showed less change in their performance in the Stroop task when faced with high cognitive load (high task difficulty level). However, monolinguals showed a significant decrease in their performance when the cognitive load increased. Our data support the "Bilingual Advantage" view. However, this advantage is highlighted in cognitively demanding tasks.

neuroscience↗

bioRxiv2019

Expansion of a subset within C2 clade of Escherichia coli sequence type 131 (ST131) is driving the increasing rates of Aminoglycoside resistance: a molecular epidemiology report from Iran

The most important lineage of Escherichia coli, named sequence type 131 (ST131) is a pandemic clone which drives the increasing rates of antibiotic resistance. While the pervasiveness of ST131 clade C, especially subclades C2 and C1-M27 has been demonstrated in numerous global surveys, no report about the ST131 clades and its virotypes has been published from Iran, so far. So, in this study we investigated and compared the virotypes, antibiotic susceptibility patterns, resistance/virulence determinants and clonality of ST131 clades collected during one-year surveillance study. Most of isolates belonged to clade C2 (34/76 [44.7%]), with the highest virulence factor (VF) scores and resistance rates. The distinctive profiles of clade C2 virulence genes were revealed by "principle coordinates analysis" (PcoA) test. The distribution of hlyA/cnf1virulence genes among clade C2 was not uniform, so that positive strains showed significantly higher rates of resistance markers (blaCTX-M-15, blaOXA-1, aac6Ib/Ib-cr and aac3IIa) and ampicillin- sulbactam/gentamicin/tobramycin resistance. Virotype C as the most common virotype (48.7%) was predominant among clade C1 population, while almost all of virotypes E and F [(22/23), 95.6%] strains belonged to clade C2, with the highest VF scores and aminoglycoside resistance rates. "Multi locus variable Number tandem repeats analysis" (MLVA) clustered clades C1 and C2 together, while clades A and B strains were mostly identified as singletons. Appearance of virotypes E and F among clade C2 strains with higher rates of aminoglycoside resistance/virulence genes content demonstrate the shifting dynamics of this pandemic clone in response to antibiotic selection pressure by establishing the newly-emerged subsets.

microbiology↗