Biology subjects

Chen, Y.-S.

Publications and source records attributed to Chen, Y.-S..

3 recordsLinked to original sources

bioRxiv2018

Bloodstream Infection with Extended-spectrum Beta-lactamase-producing Escherichia coli: the role of virulence genes

BackgroundVarious bacterial putative virulence factors are involved in the pathogenesis of bacterial infection. However, the effect of comorbidities or infection syndrome in the association of virulence factors and mortality remains inconclusive.\n\nMethodThis study addressed whether specific sequence type (ST) and virulence factors of extended-spectrum beta-lactamase-producing Escherichia coli (ESBL-EC) are associated with different outcomes in patients with bloodstream infection.121 adults from southern Taiwan with ESBL-producing E. coli bloodstream infections were enrolled during a 6-year period. Demographic data, including infection syndromes, underlying disease and outcomes, were collected. The virulence factors in isolates were analyzed by PCR and multilocus sequence typing.\n\nResultPositivity for the virulence genes iha, hlyD, sat, iut, fyu, malX, ompT, usp and traT was associated with ST131 positivity (P<0.05). Some ESBL-EC virulence genes associated with urinary tract infection (UTI) were revealed. Positivity for ST405 and the virulence genes iroN and iss was significantly associated with increased 30-day mortality (death within 30 days) on univariate analysis (P<0.05). Independent risk factors of 30-day mortality in bacteremic patients with UTI included underlying chronic liver disease and malignancy. ST131 was borderline associated with 30-day mortality. Independent risk factors associated with 30-day mortality among bacteremic patients without UTI included comorbidities and iroN positivity.\n\nConclusionIn bacteremic patients with UTI, and the ST131 clone was borderline associated with mortality. Positivity for the virulence gene iroN may be linked to mortality in bacteremic patients without UTI.

microbiology↗

bioRxiv2017

The effector TepP mediates the recruitment and activation of Phosphoinositide 3 Kinase on early Chlamydia trachomatis vacuoles

Chlamydia trachomatis delivers multiple Type 3 secreted effector proteins to host epithelial cells to manipulate cytoskeletal functions, membrane dynamics and signaling pathways. TepP is the most abundant effector protein secreted early in infection but its molecular function is poorly understood. In this report, we provide evidence that TepP is important for bacterial replication in cervical epithelial cells, the activation of Type I IFN genes, and the recruitment of Class I phosphoinositide 3 kinases (PI3K) and the signaling adaptor protein CrkL to nascent pathogen-containing vacuoles (inclusions). We also show that TepP is a target of tyrosine phosphorylation by Src kinases but these modifications do not appear to influence the recruitment of PI3K or CrkL. The translocation of TepP correlated with an increase in the intracellular pools of phosphoinositide 3,4,5 triphosphate but not the activation of the pro-survival kinase Akt, suggesting that TepP-mediated activation of PI3K is spatially restricted to early inclusions. Furthermore, we linked PI3K activity to the dampening of transcription of Type I IFN induced genes early in infection. Overall, these findings indicate that TepP can modulate cell signaling and potentially membrane trafficking events by spatially restricted activation of PI3K.

microbiology↗

bioRxiv2017

Autonomous Combinatorial Color Barcoding For Multiplexing Single Molecule RNA Visualization

Single molecular fluorescence in situ hybridization (smFISH) detects RNA transcripts with spatial information and digital molecular counting. However, the broad usage of smFISH is still hindered by the complex chemical probe conjugation or microscopy set-up, especially for investigating multiple gene expression. Here we present a multiple fluorophore enzymatic labeling method (termed HuluFISH) for smFISH probes to achieve flexible combinatorial color barcoding in single hybridization step. The multiplex capacity of HuluFISH follows an exponential growth with the increase of the number of fluorophore types. We demonstrate that this method can be used to detect cellular heterogeneity in embryonic mouse brain on single cell level.

molecular biology↗