The First Identification and Antibiogram of Clostridium perfringens Type C Isolated from Soil and The Feces of Dead Foals in South Korea
ANIMALS
Authors: Park, Chul Song; Hwang, Ji Yong; Cho, Gil Jae
Abstract
Simple Summary Clostridium (C.) perfringens in horses causes acute enteritis and death, but research on C. perfringens in South Korea is virtually nonexistent. The purpose of this study was to discover the cause of death of numerous South Korean foals. C. perfringens was isolated from 25 (11.1%) of 225 sampled horses and from 16 (35.56%) of 45 farms investigated in this study. Of the 25 C. perfringens isolates, 15 (60%) were type A and 10 (40%) were type C. Type C was observed on all the farms where the foals' deaths occurred. The antimicrobial susceptibility test was performed using MIC (Minimum Inhibitory Concentration) Evaluator strips test. These results are the first to identify one of the causes of acute foal death in South Korea and can be used as a criterion to determine the cause of acute foal death and to select effective antibiotics. Clostridium (C.) perfringens was isolated from 25 (11.1%) of 225 sampled horses and from 16 (35.56%) of 45 farms. All of the samples were negative for cpe, etx, itx, NetF genes and cpa gene were detected in 100% (25 of 25) of the samples that were positive for C. perfringens. cpb and cpb2 were detected in 40.0% (10 of 25) and 60.0% (15 of 25) of the samples that were positive for C. perfringens, respectively. Of the 25 C. perfringens isolates, 15 (60%) were type A and 10 (40%) were type C. Type C was observed on all the farms where the foals' deaths occurred. None of the isolates were positive for type B, type D, or type E. The MIC Evaluator strips antimicrobial susceptibility test showed meropenem (96%), ampicillin (92%), amoxicillin/clavulanic acid (84%), and tetracycline (8%) sensitivity.
Pro-inflammatory cytokines reduce human TAFI expression via tristetraprolin-mediated mRNA destabilisation and decreased binding of HuR
THROMBOSIS AND HAEMOSTASIS
Authors: Komnenov, Dragana; Scipione, Corey A.; Bazzi, Zainab A.; Garabon, Justin J. W.; Koschinsky, Marlys L.; Boffa, Michael B.
Abstract
Thrombin activatable fibrinolysis inhibitor (TAFI) is the zymogen form of a basic carboxypeptidase (TAFIa) with both anti-fibrinolytic and anti-inflammatory properties. The role of TAFI in inflammatory disease is multifaceted and involves modulation both of specific inflammatory mediators as well as of the behaviour of inflammatory cells. Moreover, as suggested by in vitro studies, inflammatory mediators are capable of regulating the expression of CPB2, the gene encoding TAFI. In this study we addressed the hypothesis that decreased TAFI levels observed in inflammation are due to post-transcriptional mechanisms. Treatment of human HepG2 cells with pro-inflammatory cytokines TNF alpha, IL-6 in combination with IL-1 beta, or with bacterial lipopolysaccharide (LPS) decreased TAFI protein levels by approximately two-fold over 24 to 48 hours of treatment. Conversely, treatment of HepG2 cells with the anti-inflammatory cytokine IL-10 increased TAFI protein levels by two-fold at both time points. We found that the mechanistic basis for this modulation of TAFI levels involves binding of tristetraprolin (TTP) to the CPB2 3'-UTR, which mediates CPB2 mRNA destabilisation. In this report we also identified that HuR, another ARE-binding protein but one that stabilises transcripts, is capable of binding the CBP2 3'UTR. We found that pro-inflammatory mediators reduce the occupancy of HuR on the CPB2 3'-UTR and that the mutation of the UP binding site in this context abolishes this effect, although UP and HuR appear to contact discrete binding sites. Interestingly, all of the mediators tested appear to increase TAFI protein expression in THP-1 macrophages, likewise through effects on CPB2 mRNA stability.