INTRODUCTION: Red blood cells (RBCs), also known as erythrocytes, are underestimated in their role in the immune system. In mammals, erythrocytes undergo maturation that involves the loss of nuclei, resulting in limited transcription and protein synthesis capabilities. However, the nucleated nature of non-mammalian RBCs is challenging this conventional understanding of RBCs. Notably, in bony fishes, research indicates that RBCs are not only susceptible to pathogen attacks but express immune receptors and effector molecules. However, given the abundance of RBCs and their interaction with every physiological system, we postulate that they act in surveillance as sentinels, rapid responders, and messengers. METHODS: We performed a series of in vitro experiments with Cyprinus carpio RBCs exposed to Aeromonas hydrophila, as well as in vivo laboratory infections using different concentrations of bacteria. RESULTS: qPCR revealed that RBCs express genes of several inflammatory cytokines. Using cyprinid-specific antibodies, we confirmed that RBCs secreted tumor necrosis factor alpha (TNFα) and interferon gamma (IFNγ). In contrast to these indirect immune mechanisms, we observed that RBCs produce reactive oxygen species and, through transmission electron and confocal microscopy, that RBCs can engulf particles. Finally, RBCs expressed and upregulated several putative toll-like receptors, including tlr4 and tlr9, in response to A. hydrophila infection in vivo. DISCUSSION: Overall, the RBC repertoire of pattern recognition receptors, their secretion of effector molecules, and their swift response make them immune sentinels capable of rapidly detecting and signaling the presence of foreign pathogens. By studying the interaction between a bacterium and erythrocytes, we provide novel insights into how the latter may contribute to overall innate and adaptive immune responses of teleost fishes.

• MeSH
• Aeromonas hydrophila * imunologie   MeSH
• cytokiny * metabolismus   imunologie   MeSH
• erytrocyty * imunologie   metabolismus   MeSH
• fagocytóza imunologie   MeSH
• gramnegativní bakteriální infekce * imunologie   MeSH
• kapři * imunologie   mikrobiologie   MeSH
• nemoci ryb * imunologie   mikrobiologie   MeSH
• PAMP struktury imunologie   MeSH
• přirozená imunita MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Bacterial diseases are common in ornamental fish, more frequently associated with ubiquitous bacteria from the aquarium environment. The disease can lead to fish mortality and cause high economic losses if not rapidly controlled. The aim of this study was to identify the main causative bacterial agents of infection in ornamental fish with different clinical signs. A total of 126 freshwater fish, from 12 families and 38 species, with clinical signs were collected in a wholesaler in São Paulo, SP, Brazil. Samples were taken from the eye, skin ulcers, kidneys, and gills, plated on MacConkey, CHROMagar Orientation, and blood agar and incubated under aerobic and anaerobic conditions. Bacterial identification was performed by MALDI-TOF mass spectrometry. From the 126 studied animals, 112 were positive for bacterial isolation. Among the positive animals, 32.1% presented infection caused by a single bacterial species, while in the remaining 67.9%, two to six different bacterial species were identified. A total of 259 bacterial strains were obtained and classified among 46 bacterial species. The species of higher frequency were Aeromonas veronii (26.3%), Aeromonas hydrophilla (16.2%), Shewanella putrefaciens (7.3%), Citrobacter freundii (8.1%), Vibrio albensis (5.8%), and Klebsiella pneumoniae (4.2%). MALDI-TOF MS showed to be a rapid method for diagnosis of bacterial disease outbreaks in ornamental fish establishments.

• MeSH
• Aeromonas * MeSH
• lidé MeSH
• nemoci ryb * MeSH
• ryby MeSH
• sladká voda MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Brazílie MeSH

Out of six samples of wastewater produced in the dairy industry, taken in 2017 at various places of dairy operations, 86 bacterial strains showing decarboxylase activity were isolated. From the wastewater samples, the species of genera Staphylococcus, Lactococcus, Enterococcus, Microbacterium, Kocuria, Acinetobacter, Pseudomonas, Aeromonas, Klebsiella and Enterobacter were identified by the MALDI-TOF MS and biochemical methods. The in vitro produced quantity of eight biogenic amines (BAs) was detected by the HPLC/UV-Vis method. All the isolated bacteria were able to produce four to eight BAs. Tyramine, putrescine and cadaverine belonged to the most frequently produced BAs. Of the isolated bacteria, 41% were able to produce BAs in amounts >100 mg L-1. Therefore, wastewater embodies a potential vector of transmission of decarboxylase positive microorganisms, which should be taken into consideration in hazard analyses within foodstuff safety control. The parameters of this wastewater (contents of nitrites, nitrates, phosphates, and proteins) were also monitored.

• MeSH
• Acinetobacter MeSH
• Aeromonas MeSH
• biogenní aminy chemie   MeSH
• chemické látky znečišťující vodu chemie   izolace a purifikace   MeSH
• Enterobacter MeSH
• Enterococcus MeSH
• karboxylyasy chemie   MeSH
• Klebsiella MeSH
• Lactobacillus MeSH
• Lactococcus MeSH
• Microbacterium MeSH
• mikrobiologie vody MeSH
• mlékárenství * MeSH
• odpadní voda analýza   mikrobiologie   MeSH
• Pediococcus MeSH
• Pseudomonas MeSH
• spektrofotometrie ultrafialová MeSH
• spektrometrie hmotnostní - ionizace laserem za účasti matrice MeSH
• Staphylococcus MeSH
• Streptococcus MeSH
• vysokoúčinná kapalinová chromatografie MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Evropa MeSH

Článek popisuje naše praktické zkušenosti s použitím hirudoterapie u aortální tromboembolie koček a srovnání s ostatními mož-nostmi jejího řešení. Pojednává o kočičí kardiomyopatii a aortální tromboembolii jako jejím relativně častém důsledku. Obecně je představena veterinární hirudoterapie a její možnosti použití. Popisujeme naše úspěšné použití léčby pijavicemi v této indikaci a její výsledky. Rozšířili jsme publikované indikace hirudoterapie k trombolýze a tromboprofylaxi u aortální tromboembolie koček.

The article describes our practical experience with the use of hirudotherapy in aortic thromboembolism of cats and comparison with other possibilities of its solution. It deals with cat cardiomyopathy and aortic thromboembolism as a relatively frequent con-sequence. generally, veterinary hirudotherapy and its possibilities of use are introduced. We describe our successful use of leech treatment in this indication and its results. We have extended the publicated indications of hirudotherapy to thrombolysis and thromboprophylaxis in aortic thromboembolism in cats.

• MeSH
• Aeromonas hydrophila patogenita   MeSH
• aorta patologie   MeSH
• echokardiografie statistika a číselné údaje   veterinární   MeSH
• fatální výsledek MeSH
• hirudiny fyziologie   MeSH
• kardiomyopatie komplikace   veterinární   MeSH
• kočky MeSH
• kontraindikace MeSH
• přikládání pijavic * metody   ošetřování   veterinární   MeSH
• tromboembolie * diagnóza   etiologie   patofyziologie   prevence a kontrola   terapie   veterinární   MeSH
• výsledek terapie MeSH
• zvířata MeSH
• Check Tag
• kočky MeSH
• zvířata MeSH
• Publikační typ
• kazuistiky MeSH

Karst rivers are of great interest for commercial fishing and aquaculture, yet they are quite vulnerable aquatic environments because the permeable karst rocks do not effectively filter out contaminants. To understand the current state of karst rivers water quality, we analysed the physico-chemical and microbiological parameters, focusing on antibiotic pollution and the emergence of antibiotic-resistant microbes of three such rivers in Croatia. Water quality varied between classes I and II across sampling sites, and the numbers of total coliforms, enterococci and heterotrophic bacteria varied substantially among sites. Swabs from fish gills, spleen, liver and kidneys were cultured and 94 isolates identified by MALDI-TOF mass spectrometry. The predominant genus was Aeromonas (42.5% of all identified isolates), known for its adaptability to polluted environments and its frequent association with antibiotic resistance. Of the selected Aeromonas isolates known as most pathogenic, half were resistant to at least three antibiotic categories. The Enterobacteriaceae family was represented by the greatest number of genera, most of which are pathogenic for humans and animals and are spoilage bacteria for fish. The results of this study highlight the extent of antibiotic contamination in aquatic environments and the increasing threat of pathogenic and spoilage bacteria in traditionally high-quality karst rivers.

• MeSH
• Aeromonas * genetika   MeSH
• antibakteriální látky farmakologie   MeSH
• lidé MeSH
• mikrobiální testy citlivosti MeSH
• řeky * MeSH
• voda MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Černé moře MeSH
• Chorvatsko MeSH

Flumequine was nano-immobilized by self-assembly on iron oxide nanoparticles, called surface active maghemite nanoparticles (SAMNs). The binding process was studied and the resulting core-shell nanocarrier (SAMN@FLU) was structurally characterized evidencing a firmly immobilized organic canopy on which the fluorine atom of the antibiotic was exposed to the solvent. The antibiotic efficacy of the SAMN@FLU nanocarrier was tested on a fish pathogenic bacterium (Aeromonas veronii), a flumequine sensitive strain, in comparison to soluble flumequine and the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) were assessed. Noteworthy, the MIC and MBC of soluble and nanoparticle bound drug were superimposable. Moreover, the interactions between SAMN@FLU nanocarrrier and microorganism were studied by transmission electron microscopy evidencing the ability of the complex to disrupt the bacterial wall. Finally, a preliminary in vivo test was provided using Daphnia magna as animal model. SAMN@FLU was able to protect the crustacean from the fatal consequences of a bacterial infection and showed no sign of toxicity. Thus, in contrast with the strength of the interaction, nano-immobilized FLU displayed a fully preserved antimicrobial activity suggesting the crucial role of fluorine in the drug mechanism of action. Besides the importance for potential applications in aquaculture, the present study contributes to the nascent field of nanoantibiotics.

• MeSH
• Aeromonas veronii účinky léků   MeSH
• antibakteriální látky chemie   farmakologie   MeSH
• Daphnia účinky léků   mikrobiologie   MeSH
• fluorochinolony chemie   farmakologie   MeSH
• magnetické nanočástice chemie   MeSH
• mikrobiální testy citlivosti MeSH
• molekulární struktura MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

p38 mitogen-activated protein kinase (MAPK) is an important protein which plays a key role in regulating the innate immunity, so exploring its molecular characterization is helpful in understanding the resistance against microbial infections in cultured fish. Here, a full-length cDNA of p38 MAPK was cloned from liver of blunt snout bream (Megalobrama amblycephala) which covered 2419 bp with an open reading frame of 1086 bp encoding 361 amino acids. p38 MAPK contained the characteristic structures of Thr-Gly-Tyr (TGY) motif and substrate binding site Ala-Thr-Arg-Trp (ATRW), which are conserved in MAPK family. To investigate p38 MAPK functions, two in vivo experiments were carried out to examine its expression following ammonia exposure and bacterial challenge. Also, an in vitro experiment was conducted to assess the role of p38 MAPK in inflammation of primary hepatocytes induced by lipopolysaccharide (LPS). The results showed the ubiquitous expression of p38 MAPK in all the tested tissues with varying levels. p38 MAPK mRNA expression was significantly up-regulated by ammonia stress and Aeromonas hydrophila challenge, and altered in a time-dependent manner. Moreover, the results indicated that the inflammatory response induced by LPS in hepatocytes is p38 MAPK dependent as knockdown of p38 MAPK using siRNA technology depressed the expression of IL-1β and IL-6. The findings in this study showed that p38 MAPK has anti-stress property, and plays key role in protection against bacterial infection and inflammation in blunt snout bream.

• MeSH
• Aeromonas hydrophila fyziologie   MeSH
• amoniak škodlivé účinky   MeSH
• buněčná imunita genetika   MeSH
• Cyprinidae genetika   imunologie   MeSH
• fylogeneze MeSH
• gramnegativní bakteriální infekce imunologie   MeSH
• lipopolysacharidy farmakologie   MeSH
• mitogenem aktivované proteinkinasy p38 chemie   genetika   imunologie   MeSH
• náhodné rozdělení MeSH
• nemoci ryb imunologie   MeSH
• přirozená imunita genetika   MeSH
• regulace genové exprese imunologie   MeSH
• rybí proteiny chemie   genetika   imunologie   MeSH
• sekvence aminokyselin MeSH
• sekvence nukleotidů MeSH
• sekvenční seřazení veterinární   MeSH
• stanovení celkové genové exprese veterinární   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Aeromonads represent bacteria thought to be primarily mostly autochthonous to aquatic environments. This study was focused on the relation with antibiotics and enterocins of identified Aeromonas species isolated from the intestine of trouts living in Slovakian aquatic sources. Intestinal samples from 50 trouts (3 Salmo trutta and 47 Salmo gairdnerii) were collected in April of years 2007, 2010, and 2015 from trouts of different water sources in Slovakia (pond Bukovec near Košice, river Čierny Váh). Due to the MALDI-TOF mass spectrometry evaluation, 25 strains were proposed to the genus Aeromonas involving nine different species (Aeromonas bestiarum-nine strains, Aer. salmonicida-four strains, Aer. encheleia, Aer. eucrenophila, Aer. molluscorum, Aer. media, Aer. sobria, Aer. popoffii, Aer. veronii). Phenotypic evaluation of individual strains confirmed their species identification. Twenty-five strains of different Aeromonas species were sensitive to azithromycin, amikacin, mecillinam, mezlocillin, piperacillin, gentamicin, chloramphenicol, and tetracycline. On the other side, they were resistant to carbenicillin and ticarcillin. The growth of Aer. bestiarum R41/1 was inhibited by treatment with Ent M and Ent 2019 (inhibition activity 100 AU/mL). Aer. bestiarum R47/3 was inhibited by eight enterocins (100 AU/mL). It is the first study testing enterocins to inhibit the growth of Aeromonas species from trouts.

• MeSH
• Aeromonas klasifikace   účinky léků   MeSH
• antibakteriální látky farmakologie   MeSH
• fenotyp MeSH
• genotyp MeSH
• nemoci ryb mikrobiologie   MeSH
• přemostěné cyklické sloučeniny MeSH
• pstruh mikrobiologie   MeSH
• spektrometrie hmotnostní - ionizace laserem za účasti matrice * MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Slovenská republika MeSH

Pectinatella magnifica, an invasive bryozoan, might significantly affect ecosystem balance due to its massive occurrence in many areas in Europe and other parts of the world. Biological and chemical analyses are needed to get complete information about the impact of the animal on the environment. In this paper, we aimed to evaluate in vitro cytotoxic effects of five extracts prepared from P. magnifica using LDH assay on THP-1 cell line. Antimicrobial activities of extracts against 22 different bacterial strains were tested by microdilution method. Our study showed that all extracts tested, except aqueous portion, demonstrated LD50 values below 100 μg/mL, which indicates potential toxicity. The water extract of P. magnifica with LD50 value of 250 μg/mL also shows potentially harmful effects. Also, an environmental risk resulting from the presence and increasing biomass of potentially toxic benthic cyanobacteria in old colonies should not be underestimated. Toxicity of Pectinatella extracts could be partially caused by presence of Aeromonas species in material, since we found members of these genera as most abundant bacteria associated with P. magnifica. Furthermore, P. magnifica seems to be a promising source of certain antimicrobial agents. Its methanolic extract, hexane, and chloroform fractions possessed selective inhibitory effect on some potential pathogens and food spoiling bacteria in the range of MIC 0.5-10 mg/mL. Future effort should be made to isolate and characterize the content compounds derived from P. magnifica, which could help to identify the substance(s) responsible for the toxic effects of P. magnifica extracts.

• MeSH
• Aeromonas chemie   MeSH
• antibakteriální látky chemie   farmakologie   MeSH
• Bacteria účinky léků   MeSH
• bakteriální toxiny farmakologie   MeSH
• Bryozoa chemie   mikrobiologie   MeSH
• buněčné linie MeSH
• chloroform farmakologie   MeSH
• hexany farmakologie   MeSH
• lidé MeSH
• methanol farmakologie   MeSH
• mikrobiální testy citlivosti MeSH
• testy toxicity MeSH
• viabilita buněk účinky léků   MeSH
• zavlečené druhy MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

The nucleotide sequences of three IncU plasmids from Aeromonas spp. isolated from ornamental fish are described. They had a typical IncU backbone for plasmid replication and maintenance functions, but conjugative transfer modules were disrupted. The gene qnrS2 was inserted into mpR as a mobile insertion cassette. Novel Tn3 family transposons carrying putative toxin-antitoxin and plasmid stability genes were identified. The study demonstrates high plasticity of IncU plasmids from aquatic environments.

• MeSH
• Aeromonas účinky léků   genetika   izolace a purifikace   MeSH
• antibakteriální látky farmakologie   MeSH
• bakteriální geny * MeSH
• bakteriální léková rezistence genetika   MeSH
• bakteriální proteiny genetika   metabolismus   MeSH
• chinolony farmakologie   MeSH
• gramnegativní bakteriální infekce mikrobiologie   veterinární   MeSH
• mikrobiální testy citlivosti MeSH
• nemoci ryb mikrobiologie   MeSH
• otevřené čtecí rámce MeSH
• plazmidy chemie   metabolismus   MeSH
• regulace genové exprese u bakterií * MeSH
• ryby mikrobiologie   MeSH
• sekvenční analýza DNA MeSH
• transpozibilní elementy DNA MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH