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AIMS: The aim of this study was to determine phenotypic and genotypic resistance, virulence and clonal relationship of aeromonads and related species isolated from Czech carp fisheries. METHODS AND RESULTS: Forty-nine isolates obtained from a total of 154 fish from three breeding facilities were species identified using matrix-assisted laser desorption/ionization time of flight and the sequencing of the rpoB housekeeping gene. Most Aeromonas isolates were identified as Aeromonas veronii (94%, n = 34). Susceptibility to six antibiotics (oxytetracycline, flumequine, florfenicol, sulphamethoxazole/trimethoprim, enrofloxacin and oxolinic acid) was tested using the disc diffusion method. The presence of resistance genes and virulence factors was verified by PCR and sequencing, and the clonal relationship was analysed using pulsed-field gel electrophoresis (PFGE). Phenotypic resistance to one or more antimicrobials was found in 32 isolates (65%, n = 49). Resistance to oxytetracycline was the most common (41%) and associated mainly with the presence of tet(E) gene, while the percentage of isolates resistant to florfenicol was low (2%). Isolates carried one to five of the tested virulence factors and showed high diversity of PFGE profiles. CONCLUSIONS: Since the highest percentage of antimicrobial resistance in aeromonads was found for oxytetracycline and the lowest percentage for florfenicol, it is suggested that florfenicol could be an adequate treatment alternative in carp fisheries. SIGNIFICANCE AND IMPACT OF THE STUDY: Increasing resistance of aeromonads to commonly used antimicrobials has become an emerging problem in fisheries. This study was conducted in relation to the practical needs to identify a suitable antibiotic as an alternative to oxytetracycline.

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BACKGROUND: It has been convincingly established that cardiopulmonary bypass routinely used in cardiac surgery induces an oxidative stress. The extensive production of reactive oxygen species occurring during cardiopulmonary bypass has a deleterious effect on the endogenous antioxidant defense pool. The recovery of antioxidant enzyme activities as well as other antioxidatively substances is one of the important tasks for the effective defense of patients in the postoperative period. AIM OF THE STUDY: Oxidative stress markers and the antioxidant status and the activities of some antioxidant enzymes were studied in patients during one-week period after cardiac revascularization performed using cardiopulmonary bypass and the results were compared with patients operated by off-pump technique. PATIENTS AND METHODS: Thirty-nine patients undergoing elective surgical revascularization (coronary artery bypass grafting) were divided in two groups: twenty-two patients operated using cardiopulmonary bypass (group A) and a group B of seventeen patients undergoing pump-off surgery. Blood samples were drawn before operation and then in course of the first week after surgery. The following biochemical parameters were estimated: plasma levels of total antioxidant status (TAS) and of thiobarbituric acid reactive substances (TBARS) as well as erythrocyte activities of two antioxidant enzymes--superoxide dismutase (SOD) and glutathione peroxidase (GPx). RESULTS: There was a significantly decreased preoperative and also postoperative levels of TAS associated with a preoperatively increased level of TBARS in group A only. In both groups of patients (especially in group B), markedly decreased activity of SOD was observed. The increase of GPx activity--especially on the third postoperative day--was not significant. CONCLUSIONS: Regardless of the surgical technique, both groups of patients had a markedly decreased antioxidant capacity with a significantly increased production of lipid peroxides especially in patients operated with cardiopulmonary bypass. The decreased antioxidant status was connected with decreased erythrocyte activity of SOD. Therefore, we recommend the regular supply of antioxidant acting substances (antioxidant vitamins and coenzyme Q10) be included in their standard therapeutic strategy especially in the preoperative period. (Tab. 2, Fig. 4, Ref: 22.)

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BACKGROUND: Routine biochemical parameters in the blood of patients with chronic cardiopathies are nonspecific and of no reliable diagnostic value. OBJECTIVES: Since marked changes of some biochemical blood parameters concerning the oxidative metabolism of the organism were observed in patients with acute myocardial diseases, the aim of this study was to estimate some antioxidant enzyme activities and metabolites in the blood of patients with cardiopathies-diseases with chronic heart failure of unknown origin. METHODS: In 21 hospitalized patients with cardiopathy the venous blood samples were analyzed for plasma levels of thiobarbituric acid reactive substances (TBARS) as representatives of lipid peroxidation, levels of selenium and zinc as well as the activities of superoxide dismutase (SOD) and glutathione peroxidase (GPX) and reduced glutathione (GSH) level in erythrocytes. RESULTS: Comparing the group of 25 clinically healthy individuals some marked changes in enzyme activities and metabolite levels were found in patients with cardiopathy: a significant increase of plasma TBARS and-on the other hand-markedly decreased activities of SOD and GPX and of GSH level in erythrocytes. Also a decreased plasma selenium level was observed in patients. CONCLUSIONS: A marked decrease of antioxidant enzyme activities and GSH levels suggest a possible drop in total antioxidant status of patients with cardiopathy. Raised TBARS plasma levels might be regarded as a decreased ability of organism to abolish the produced free reactive oxygen forms leading thus to rise in lipoprotein rare.

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