Genotypic and phenotypic diversity differences of presumptive commensal and avian pathogenic E. coli

1. The objective of the experiment was to characterise the genotypic and phenotypic differences between presumptive commensal E. coli and avian pathogenic E. coli (APEC) of poultry. 2. DNA was extracted from 65 confirmed APEC E. coli from chicken, 100 presumptive commensal E. coli from healthy turkey and 35 from healthy chicken. Enterobacterial repetitive intergenic consensus PCR (ERIC-PCR) and virulence factors genotyping was performed to characterise genetic features. 3. Carbon source utilisation and antimicrobial susceptibility tests were performed to characterise phenotypic features of isolates. 4. The genetic divergence between E. coli strains tested by ERIC-PCR profiles and virulence associated genes showed a clear genetic separation between E. coli APEC and turkey E. coli strains. 5. The carbon utilisation profile of turkey isolates was different from chicken and APEC strains; whereas antimicrobial susceptibility was highest for turkey isolates (53%), and lowest for APEC strains (33.8%). 6. The study showed a significant negative correlation between utilisation of arabitol and adonitol with different virulence determinants tested, which suggests that the ability to utilise some uncommon carbon sources may be used to discriminate between presumptive commensal E. coli and APEC

Accessibility to biologics and its impact on disease activity and quality of life in patients with rheumatoid arthritis in Kuwait

Objective: Biologics are indicated in rheumatoid arthritis (RA) in case of persistent high disease activity despite conventional disease-modifying anti-rheumatic drugs (cDMARDs) or patients with contraindications to cDMARDs or poor prognostic factors. The purpose of this study was to compare the prescription rates of biologics in Kuwaiti and non-Kuwaiti patients and to assess whether this had an impact on disease activity and quality of life in RA patients. Methods: Data were extracted from the Kuwait Registry for Rheumatic Diseases. Adult patients who satisfied the ACR classification criteria for RA from four major hospitals in Kuwait were evaluated from February 2013 through May 2018. The treatment agents, disease activity, and quality of life of Kuwaiti patients were compared with non-Kuwaiti patients. Results: A total of 1651 RA patients were included; 806 (48.8%) were Kuwaiti patients. Among Kuwaiti patients, 62.5% were on biologic drugs in comparison with 14% of non-Kuwaiti patients. In comparison with non-Kuwaiti patients, Kuwaiti patients had significantly lower numbers of swollen joints (p < 0.001) and disease activity score-28 scores (p = 0.02) and less steroid use (p < 0.001) yet a significantly higher health assessment questionnaire-disability index (p < 0.001). Regression analysis showed that DAS-28 scores were significantly associated with the treatment type (p < 0.001) and that nationality was significantly predictive of the treatment type (p < 0.001). Conclusion: In the setting of easy accessibility to treatment for Kuwaiti patients, biologics were prescribed by rheumatologists at a higher rate than for non-Kuwaitis. This may explain the lower disease activity and the lower rate of steroid use in Kuwaiti patients than non-Kuwaitis. Key points: • Significant discrepancies in the rates of prescribing biologic therapies between KP and NKP in Kuwait were observed. • Several treatment outcomes were significantly better in the KP group than in the NKP group even after adjustment of confounding factors. • The poor access to biologic therapies was suggested to limit the effectiveness of RA treatments in the NKP group

Thymol tolerance in Escherichia coli induces morphological, metabolic and genetic changes.

Background: Thymol is a phenolic compound used for its wide spectrum antimicrobial activity. There is a limited understanding of the antimicrobial mechanisms underlying thymol activity. To investigate this, E. coli strain JM109 was exposed to thymol at sub-lethal concentrations and after 16 rounds of exposure, isolates with a 2-fold increased minimal inhibitory concentration (MIC) were recovered (JM109-Thyr). The phenotype was stable after multiple sub-cultures without thymol. Results: Cell morphology studies by scanning electron microscopy (SEM) suggest that thymol renders bacterial cell membranes permeable and disrupts cellular integrity. 1H Nuclear magnetic resonance (NMR) data showed an increase in lactate and the lactic acid family amino acids in the wild type and JM109-Thyr in the presence of thymol, indicating a shift from aerobic respiration to fermentation. Sequencing of JM109-Thyr defined multiple mutations including a stop mutation in the acrR gene resulting in a truncation of the repressor of the AcrAB efflux pump. AcrAB is a multiprotein complex traversing the cytoplasmic and outer membrane, and is involved in antibiotic clearance. Conclusions: Our data suggests that thymol tolerance in E. coli induces morphological, metabolic and genetic changes to adapt to thymol antimicrobial activity. Keywords: Escherichia coli, Thymol, Resistance, Acriflavine resistance regulator, Efflux pum

JAK Inhibition Prevents DNA Damage and Apoptosis in Testicular Ischemia-Reperfusion Injury via Modulation of the ATM/ATR/Chk Pathway

Testicular ischemia reperfusion injury (tIRI) causes oxidative stress-induced DNA damage leading to germ cell apoptosis (GCA). The aim of the study is to establish a direct link between JAK2 activation and the DNA damage response (DDR) signaling pathways and their role in tIRI-induced GCA using AG490, a JAK2 specific inhibitor. Male Sprague Dawley rats (n = 36) were divided into three groups: sham, unilateral tIRI and tIRI + AG490 (40 mg/kg). During tIRI, augmentation in the phosphorylation levels of the JAK2/STAT1/STAT3 was measured by immunohistochemistry. Observed spermatogenic arrest was explained by the presence of considerable levels of DSB, AP sites and 8OHdG and activation of caspase 9, caspase 3 and PARP, which were measured by colorimetric assays and TUNEL. The ATM/Chk2/H2AX and ATR/Chk1 pathways were also activated as judged by their increased phosphorylation using Western blot. These observations were all prevented by AG490 inhibition of JAK2 activity. Our findings demonstrate that JAK2 regulates tIRI-induced GCA, oxidative DNA damage and activation of the ATM/Chk2/H2AX and ATR/Chk1 DDR pathways, but the cell made the apoptosis decision despite DDR efforts