Microbial signaling and systems biology

A report of the symposium on Signaling and Systems Biology held during the Society for General Microbiology Spring Meeting, 29-30 March 2010, Edinburgh, UK.     

Consequences of concurrent Ascaridia galli and Escherichia coli infections in chickens

   

The principal aim of this study was to evaluate dissociative anaesthesia for castration of colts during field conditions. Three dissociative anaesthetic protocols were evaluated during castration of colts in an animal hospital. The protocol considered to be the most suitable was thereafter evaluated during castration of colts under field conditions. Respiratory and haemodynamic parameters and the response to surgery were determined during anaesthesia. All horses breathed air spontaneously during anaesthesia. Under hospital conditions 26 colts were randomised to receive one of three anaesthetic protocols: Romifidine and tiletamine-zolazepam (RZ); acepromazine, romifidine and tiletamine-zolazepam (ARZ); or acepromazine, romifidine, butorphanol and tiletamine-zolazepam (ARBZ). The surgeon was blinded to the anaesthetic protocol used and decided whether supplemental anaesthesia was needed to complete surgery. Under field conditions 31 colts were castrated during anaesthesia with the ARBZ protocol. All inductions, anaesthesia and recoveries were calm and without excitation under both hospital and field conditions. Surgery was performed within 5–20 minutes after the horses had assumed lateral recumbency during both hospital and field castrations. Under hospital conditions some horses needed supplemental anaesthesia with all three anaesthetic protocols to complete surgery. Interestingly, none of the horses castrated with protocol ARBZ under field conditions needed additional anaesthesia. Cardiorespiratory changes were within acceptable limits in these clinically healthy colts.     

A comparison of the illness beliefs of people with angina and their peers: a questionnaire study

Background  

What people believe about their illness may affect how they cope with it. It has been suggested that such beliefs stem from those commonly held within society . This study compared the beliefs held by people with angina, regarding causation and coping in angina, with the beliefs of their friends who do not suffer from angina.     

Biological activity of ovine IL-23 expressed using a foot-and-mouth disease virus 2A self-cleaving peptide

Hetero-dimeric cytokines often require equi-molar expression of both subunits to achieve biological activity. Previously, we expressed ovine IL-12 p40 and p35 linked using a self-cleaving 2A peptide from foot-and-mouth disease virus (FMDV). We now generated a new improved vector for the expression of hetero-dimeric cytokines and demonstrate the more general applicability of this strategy by cloning and expressing ovine IL-23 using the 2A peptide to link IL-12/IL-23 p40 and p19. The resulting protein was shown to be biologically active when expressed in mammalian COS cells. IL-23 plays a significant role in the differentiation of Th17 cells as well as autoimmunity and the regulation of inflammatory processes. As such this reagents will be invaluable in the unravelling of regulation of the ovine immune system for both veterinary and human animal model applications.     

Study of permeation and blocker binding in TMEM16A calcium-activated chloride channels

We studied the effects of mutations of positively charged amino acid residues in the pore of X. tropicalis TMEM16A calcium-activated chloride channels: K613E, K628E, K630E; R646E and R761E. The activation and deactivation kinetics were not affected, and only K613E showed a lower current density. K628E and R761E affect anion selectivity without affecting Na⁺ permeation, whereas K613E, R646E and the double mutant K613E + R646E affect anion selectivity and permeability to Na⁺. Furthermore, altered blockade by the chloride channel blockers anthracene-9-carboxylic acid (A-9-C), 4, 4''-Diisothiocyano-2,2''-stilbenedisulfonic acid (DIDS) and T16inh-A01 was observed. These results suggest the existence of 2 binding sites for anions within the pore at electrical distances of 0.3 and 0.5. These sites are also relevant for anion permeation and blockade.