ABSTRACT
OBJECTIVE: This study aimed to determine the effect and mechanisms of remote postconditioning (RPC) upon ischaemia-reperfusion injury (IRI) in the ischaemic mouse hindlimb. DESIGN: RPC is the brief application of ischaemia to remote organs immediately before reperfusion of an ischaemic target organ, and it is a novel approach to IRI attenuation. MATERIALS AND METHODS: Right hindlimb ischaemia was induced in mice using a rubber tourniquet, the release of which initiated reperfusion. We established RPC by 5 min of ischaemia followed by 5 min of reperfusion in the left hindlimb immediately before right hindlimb reperfusion. The wet/dry ratio of skeletal muscle (degree of tissue oedema), myeloperoxidase (MPO) activity (accumulation of neutrophils), and nitroblue tetrazolium reduction (tissue necrosis) were evaluated. We also intra-peritoneally injected 8-sulphophenyltheophylline (SPT), an adenosine receptor inhibitor, in RPC mice. RESULTS: Wet/dry ratio, MPO activity and tissue necrosis were significantly lower in the RPC group than in the control group, and injection of SPT impaired the protective effect of RPC. CONCLUSIONS: Our results show that RPC attenuated IRI in murine hindlimb ischaemia, possibly through endogenous adenosine receptor activation, and that RPC might serve as a promising therapeutic option for treating serious limb ischaemia.
Subject(s)
Ischemic Postconditioning , Muscle, Skeletal/blood supply , Muscle, Skeletal/metabolism , Receptors, Purinergic P1/metabolism , Reperfusion Injury/prevention & control , Signal Transduction , Animals , Disease Models, Animal , Edema/etiology , Hindlimb , Male , Mice , Mice, Inbred C57BL , Muscle, Skeletal/pathology , Necrosis , Neutrophil Infiltration , Purinergic P1 Receptor Antagonists/pharmacology , Receptors, Purinergic P1/drug effects , Reperfusion Injury/metabolism , Reperfusion Injury/pathology , Reperfusion Injury/physiopathology , Signal Transduction/drug effects , Time Factors , TourniquetsABSTRACT
Efficacies of 8 antibiotics against Pseudomonas aeruginosa in the relation to serotypes and clinical sources were investigated on 50 strains isolated from patients at Nagoya Ekisaikai Hospital between August and September, 1986. Disk sensitivity test was carried out simultaneously for 5 antibiotics including piperacillin (PIPC), cefoperazone (CPZ), cefsulodin (CFS), ceftazidime (CAZ) and amikacin (AMK), using the single-disk method. We also examined changes in susceptibilities of P. aeruginosa to 5 antibiotics including PIPC, CFS, fosfomycin, gentamicin (GM) and AMK during last 4 years (1983-1986). The results are summarized as follows. 1. CAZ and AMK proved to have high antibacterial potencies, and their MIC80's (concentrations to inhibit growth of 80% of objective bacteria) were both 6.25 micrograms/ml. Following these two the order of potencies were; CFS, cefpiramide (CPM), PIPC, CPZ, netilmicin (NTL), and cefmenoxime (CMX). Sixty two percent of the strains of P. aeruginosa showed high resistances (MIC greater than 50 micrograms/ml) to CPM, CPZ, NTL and CFS, 58% to PIPC, and 2% to AMK. 2. With regard to serotypes, strains belonging to type E were less susceptible than those belonging to types G and I. Type E strains showed high resistance to all antibiotics except CAZ and AMK. 3. Strains obtained from pura and secreta were relatively susceptible, while those from urines were resistant, to these antibiotics tested, in general. 4. Good correlation between MIC's obtained with the agar dilution method (MIC less than or equal to 12.5 micrograms/ml) and these with the disk sensitivity test (greater than ¿ was observed. chi 2 statistical analysis showed that the results obtained with the 2 methods were closely related (P less than 0.01). 5. P. aeruginosa showed fairly high susceptibility to AMK through the recent 4 years (1983-1986). On the other hand, highly resistant strains against CFS, PIPC, FOM and GM increased rapidly during this period.
Subject(s)
Anti-Bacterial Agents/pharmacology , Pseudomonas aeruginosa/drug effects , Drug Resistance, Microbial , Humans , Microbial Sensitivity Tests , Pseudomonas aeruginosa/isolation & purification , Serotyping , Sputum/microbiology , Time FactorsABSTRACT
We investigated in vitro synergistic activity of astromicin (ASTM) combined with beta-lactam antibiotics (cefsulodin (CFS), cefoperazone (CPZ), ceftazidime (CAZ), piperacillin (PIPC) and fosfomycin (FOM) against fresh clinical isolated Pseudomonas aeruginosa, which consisted of 13 CFS sensitive (MIC less than or equal to 3.13 micrograms/ml) and 19 CFS resistant (MIC greater than or equal to 400 micrograms/ml) strains according to the FIC index. Against CFS-sensitive P. aeruginosa, ASTM showed good synergistic activities when combined with PIPC (54%), CAZ (38%), CPZ (23%) and CFS (8%). Against CFS-resistant P. aeruginosa, ASTM also showed high synergistic activities when combined with CAZ (63%), CPZ (47%), PIPC (37%) and CFS (11%). Among the CFS-resistant P. aeruginosa, one clinical isolate showed a high sensitivity (MIC0.78 micrograms/ml) against ASTM alone.
