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Effect of quorum quenching bacteria on growth,virulence factors and biofilm formation of Yersinia ruckeri in vitro and an in vivo evaluation of their probiotic effect in rainbow trout 
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下载免费PDF全文 Somayeh Torabi Delshad Siyavash Soltanian Hassan Sharifiyazdi Peter Bossier 《Journal of fish diseases》2018,41(9):1429-1438
Five N‐acyl homoserine lactone‐degrading bacteria (quorum quenching (QQ) strains) were selected to evaluate their impacts on growth, virulence factors and biofilm formation in Yersinia ruckeri in vitro. No difference was observed among the growth pattern of Y. ruckeri in monoculture and coculture with the QQ strains. To investigate the regulation of virulence factors by quorum sensing in Y. ruckeri, cultures were supplemented with 3oxo‐C8‐HSL. The results indicated that swimming motility and biofilm formation are positively regulated by QS (p < 0.05), whereas caseinase, phospholipase and haemolysin productions are not influenced by 3oxo‐C8‐HSL (p > 0.05). The QQs were able to decrease swimming motility and biofilm formation in Y. ruckeri. QQ bacteria were supplemented to trout feed at 108 CFU/g (for 40 days). Their probiotic effect was verified by Y. ruckeri challenge either by immersion or injection in trout. All strains could significantly increase fish survival with Bacillus thuringiensis and Citrobacter gillenii showing the highest and lowest relative percentage survival (RPS) values (respectively, 85% and 38%). Besides, there was no difference between the RPS values by either immersion or injection challenge expect for B. thuringiensis. The putative involvement of the QQ capacity in the protection against Yersinia is discussed. 相似文献
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Siyavash?SoltanianEmail author Mohammad?Saeed?Fereidouni 《Fish physiology and biochemistry》2017,43(6):1645-1655
In the current study, laboratory evaluations were made to assess the immunomodulatory effect of cypermethrin on fingerlings of common carp (Cyprinus carpio L.). Results showed that 96-h LC50 of cypermethrin in common carp was estimated at 0.85 μg/L. Fish were exposed for 21 days to cypermethrin at three sub-lethal concentrations of 0.042, 0.085, and 0.17 μg/L that represented 5, 10, and 20%, respectively, of the 96-h LC50 of the pesticide for this fish species. Blood samples were taken after 7, 14, and 21 days of exposure. Immunological indices and resistance against bacterial infection were determined. Compared to the control group, the fish exposed to cypermethrin showed a significant increase in neutrophil ratio but exhibited a significant decrease in leukocyte number and lymphocyte ratio in treatments exposed to 0.17 and/or 0.085 μg/L after 21 days of exposure (p < 0.05). Serum protein level was significantly decreased in group exposed to 0.17 μg/L on day 14 and also in groups exposed to 0.085 and 0.17 μg/L on day 21 (p < 0.05). Immunoglobulin value was significantly reduced in groups exposed to 0.085 and 0.17 μg/L after 21 days of exposure (p < 0.05). Serum lysozyme activity and phagocytic activity were significantly decreased following exposure to 0.17 μg/L determined on days 14 and 21, post-exposure (p < 0.05). Mortality rate following the challenge with Aeromonas hydrophila significantly increased in fish exposed to 0.17 μg/L of cypermethrin. Overall, the present results indicate severe immunotoxicological effects of cypermethrin in common carp. Therefore, the use of cypermethrin in the proximities of common carp farms should be carefully considered. 相似文献
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Hamid Najafipour Ali Siahposht Khachaki Mohammad Khaksari Beydolah Shahouzehi Siyavash Joukar Hamid Reza Poursalehi 《Iranian Biomedical Journal》2014,18(4):225-231
Background: Accidents are the second reason for mortality and morbidity in Iran. Among them, brain injuries are the most important damage. Clarification of the effects of brain injuries on different body systems will help physicians to prioritize their treatment strategies. In this study, the effect of pure brain trauma on the cardiovascular system and lungs 24 hours post trauma was assessed. Methods: Male Wistar rats (n = 32) were divided into sham control and traumatic brain injury (TBI) groups. In TBI animals, under deep anesthesia, a blow to the head was induced by the fall of a 450 g weight from 2 m height. Twenty four hours later, heart electrocardiogram and functional indices, cardiac troponin I, IL-6, TNF-, IL-Iβ in tissue and serum, and the histopathology of heart and lung were assessed. Results: The results showed that none of the functional, biochemical, inflammatory, and histopathology indices was statistically different between the two groups at 24 hours post TBI. Indices of impulse conduction velocity in atrium (P wave duration and P-R interval) were significantly longer in the TBI group. Conclusion: Overall, no important functional and histopathologic disturbances were found in heart and lung of TBI group after 24 hours. If the data is reproduced in human studies, the medical team could allocate their priority to treatment of brain disorders of the victim in the first 24 hours of pure TBI and postpone extensive assessment of heart and lung health indices to later time, thus reducing patient and health system expenditures. Key Words: Brain injury (TBI), Cardiopulmonary, Myocardial contraction, Cytokines 相似文献
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Nima Shiry Tahoora Shomali Siyavash Soltanian Mostafa Akhlaghi 《Journal of veterinary pharmacology and therapeutics》2019,42(2):214-221
This study evaluates changes in the pharmacokinetic behavior of a single oral dose of florfenicol in rainbow trouts experimentally infected with Lactococcus garvieae or Streptococcus iniae. One hundred and fifty fish were randomly divided into three equal groups: 1—healthy fish, 2—fish inoculated with S. iniae (2.87 × 107 CFU/ml, i.p.), and 3—fish inoculated with L. garvieae (6.8 × 105 CFU/ml, i.p.). Florfenicol was administered to all groups at 15 mg/kg by oral gavage. Blood sampling was performed at 0, 2, 3, 6, 8, 12, 24, 48, 72, and 120 hr after drug administration to each group, and plasma concentration of florfenicol was assayed by HPLC method. The MICs of florfenicol were 1.2 μg/ml and 5 μg/ml against L. garviae and S. iniae, respectively. Healthy fish showed higher values for most of the PK/PD parameters as compared to fish infected with L. garvieae which was reversed in fish infected with S. iniae. Fish infected with L. garvieae showed decreased relative bioavailability accompanied by increased volume of distribution at steady‐state (Vdss) and total body clearance (ClB). Infection with S. iniae increased the peak concentration of drug after administration (Cmax) and decreased elimination half‐life (T1/2 β), central compartment volume (Vc), and Vdss. In conclusion, infection with these bacteria can affect the pharmacokinetic behavior of florfenicol in rainbow trouts as shown by decreased bioavailability and increased total body clearance and volume of distribution in L. garvieae infection and decreased volume of distribution accompanied by increased Cmax in S. iniae‐infected fish. 相似文献
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Somayeh Torabi Delshad Siyavash Soltanian Hassan Sharifiyazdi Peter Bossier 《Journal of fish diseases》2019,42(4):477-487
In this study, we evaluated the impact of the catecholamines on growth, swimming motility, biofilm formation and some virulence factors activities of pathogenic Yersinia ruckeri. Norepinephrine and dopamine (at 100 µM) significantly increased the growth of Y. ruckeri in culture media containing serum. An increase in swimming motility of the pathogen was found following the exposure to the hormones; however, no effect was seen on caseinase, phospholipase and haemolysin productions. Further, antagonists for the catecholamine receptors were observed to block some of the influences of the catecholamines. Indeed, the effects of catecholamines were inhibited by chlorpromazine (the dopaminergic receptor antagonist) for dopamine, labetalol (α‐and β‐adrenergic receptor antagonist) and phenoxybenzamine (the α‐adrenergic receptor antagonist) for norepinephrine, but propranolol (the β‐adrenergic receptor antagonist) showed no effect. Pretreatment of Y. ruckeri with the catecholamines resulted in a significant enhancement of its virulence towards rainbow trout and the antagonists could neutralize the effect of the stress hormones in vivo. In summary, our results show that the catecholamines increase the virulence of Y. ruckeri which is pathogenic to trout through increasing the motility, biofilm formation and growth. 相似文献
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Hamed Aalamifar Siyavash Soltanian Arya Vazirzadeh Mostafa Akhlaghi Vahid Morshedi Amin Gholamhosseini Mansour Torfi Mozanzadeh 《Aquaculture Nutrition》2020,26(1):156-164
A six‐week feeding trial was conducted to determine the effect of butyric acid (BA) inclusion in diet on performance of Barramundi (Lates calcarifer). Fish (12.0 ± 0.2 g) were fed with four experimental diets contained 0.0 (control), 2.5, 5.0 and 10.0 g BA/kg in triplicate. Fish fed on 5 and 10 g BA/kg diets had higher growth and total alkaline protease and lipase activities than the other treatments. Fillet protein content in BA‐supplemented groups was higher than the control. Liver catalase activity was highest in 2.5 g BA/kg group compared with the other groups. The values of liver superoxide dismutase activity and serum total protein concentration in 5 and 10 g BA/kg treatments were higher than those in the control (p < .05). Moreover, the highest and the lowest levels of serum lysozyme activity were noticed in the 10 g BA/kg and the control groups, respectively (p < .05). Also, the highest respiratory burst activity was observed in fish fed 5 g BA/kg feed. Supplementing diet with 2.5 or 5 g BA/kg resulted in higher serum haemolytic activity in fish compared with the other groups. The number of red and white blood cells increased in fish fed BA‐supplemented diets compared with the control (p < .05). In conclusion, the results of this study showed inclusion of BA at 5 g/kg diet in L. calcarifer juveniles improved growth and upgraded the general health condition by enhancing fish antioxidant enzyme activities and haemato‐immunological responses. 相似文献
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