Rapid identification of methicillin-resistant Staphylococcus aureus (MRSA) is essential for proper initial antibiotic therapy and timely set up of hygienic measures. Recently, detection of MRSA using MALDI-TOF mass spectrometer mediated by the peptide-phenol-soluble modulin (PSM-mec)-linked to the class A mec gene complex present in SCCmec cassettes types II, III, and VIII of MRSA strains, has been commercially available. We present here a multicentre study on MALDI-TOF MS detection of MRSA evincing a poor repeatability and reproducibility of the assay. The sensitivity of the assay varies between 50 and 90% in strains carrying psmMEC and psmδ genes encoding for PSM-mec and δ-toxin (a member of the PSM peptide family), respectively. No false positive results were found. The very major error calculation was 30% and the major error achieved 0%. Interlaboratory repeatability varies between 0 and 100%. No significant difference was observed with the use of different cultivation media. Our data showed a poor sensitivity of the method excluding it from the use in routine laboratory testing.
- MeSH
- bakteriální toxiny genetika MeSH
- chybná diagnóza MeSH
- diagnostické techniky molekulární * MeSH
- diagnostické testy rutinní MeSH
- lidé MeSH
- methicilin rezistentní Staphylococcus aureus genetika izolace a purifikace MeSH
- reprodukovatelnost výsledků MeSH
- senzitivita a specificita MeSH
- spektrometrie hmotnostní - ionizace laserem za účasti matrice * MeSH
- stafylokokové infekce diagnóza mikrobiologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- multicentrická studie MeSH
The aim of the present study was to characterize sporadic cases and an outbreak of NDM-like-producing Enterobacteriaceae recovered from hospital settings, in Czechia. During 2016, 18 Entrobacteriaceae isolates including 10 Enterobacter cloacae complex (9 E. xiangfangensis and 1 E. asburiae), 4 Escherichia coli, 1 Kluyvera intermedia, 1 Klebsiella pneumoniae, 1 Klebsiella oxytoca, and 1 Raoultella ornithinolytica that produced NDM-like carbapenemases were isolated from 15 patients. Three of the patients were colonized or infected by two different NDM-like producers. Moreover, an NDM-4-producing isolate of E. cloacae complex, isolated in 2012, was studied for comparative purposes. All isolates of E. cloacae complex, except the E. asburiae, recovered from the same hospital, were assigned to ST182. Additionally, two E. coli belonged to ST167, while the remaining isolates were not clonally related. Thirteen isolates carried blaNDM-4, while six isolates carried blaNDM-1 (n = 3) or blaNDM-5 (n = 3). Almost all isolates carried blaNDM-like-carrying plasmids being positive for the IncX3 allele, except ST58 E. coli and ST14 K. pneumoniae isolates producing NDM-1. Analysis of plasmid sequences revealed that all IncX3 blaNDM-like-carrying plasmids exhibited a high similarity to each other and to previously described plasmids, like pNDM-QD28, reported from worldwide. However, NDM-4-encoding plasmids differed from other IncX3 plasmids by the insertion of a Tn3-like transposon. On the other hand, the ST58 E. coli and ST14 K. pneumoniae isolates carried two novel NDM-1-encoding plasmids, pKpn-35963cz, and pEsco-36073cz. Plasmid pKpn-35963cz that was an IncFIB(K) molecule contained an acquired sequence, encoding NDM-1 metallo-β-lactamase (MβL), which exhibited high similarity to the mosaic region of pS-3002cz from an ST11 K. pneumoniae from Czechia. Finally, pEsco-36073cz was a multireplicon A/C2+R NDM-1-encoding plasmid. Similar to other type 1 A/C2 plasmids, the blaNDM-1 gene was located within the ARI-A resistance island. These findings underlined that IncX3 plasmids have played a major role in the dissemination of blaNDM-like genes in Czech hospitals. In combination with further evolvement of NDM-like-encoding MDR plasmids through reshuffling, NDM-like producers pose an important public threat.
- Publikační typ
- časopisecké články MeSH
- MeSH
- analytická chemie MeSH
- ekotoxikologie MeSH
- toxikologie MeSH
- Publikační typ
- biografie MeSH
- O autorovi
- Matoušek, Jiří, 1930-2011 Autorita
Many pesticides have been documented to induce embryotoxicity and teratogenicity in non-target aquatic biota such a fish, amphibians and invertebrates. Our review of the existing literature shows that a broad range of pesticides, representing several different chemical classes, induce variable toxic effects in aquatic species. The effects observed include diverse morphological malformations as well as physiological and behavioral effects. When development malformations occur, the myoskeletal system is among the most highly sensitive of targets. Myoskeletal effects that have been documented to result from pesticides were also known to interfere with the development of organ systems including the eyes or the heart and are also known to often cause lethal or sublethal edema in exposed organisms. The Physiological, behavioral, and population endpoints affected by pesticides include low or delayed hatching, growth suppression, as well as embryonal or larval mortality. The risks associated with pesticide exposure increase particularly during the spring. This is the period of time in which major pepticide applications take place, and this period unfortunately also coincides with many sensitive reproductive events such as spawning, egg laying, and early development of many aquatic organisms. Only few experimental studies with pesticides have directly linked developmental toxicity with key oxidative stress endpoints, such as lipid peroxidation, oxidative DNA damage, or modulation of antioxidant mechanisms. On the other hand, it has been documented in many reports that pesticide-related oxidative damage occurs in exposed adult fish, amphibians, and invertebrates. Moreover, the contribution of oxidative stress to the toxicity of pesticides has been emphasized in several recent review papers that have treated this topic. In conclusion, the available experimental data, augmented by several indirect lines of evidence, provide support to the concept that oxidative stress is a highly important mechanism in pesticide-induce reproductive or developmental toxicity. Other stressors may also act by oxidative mechanisms. This notwithstanding, there is much yet to learn about the details of this phenomenon and further research is needed to more fully elucidate the effects that pesticides have and the environmental risks they pose in the early development of aquatic organisms.
- MeSH
- chemické látky znečišťující vodu toxicita MeSH
- embryo nesavčí účinky léků MeSH
- embryonální vývoj účinky léků MeSH
- oxidační stres účinky léků MeSH
- pesticidy toxicita MeSH
- poškození DNA účinky léků MeSH
- vodní organismy účinky léků růst a vývoj MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
Wild birds are continually exposed to many anthropogenic and natural stressors in their habitats. Over the last decades, mass mortalities of wild birds constitute a serious problem and may possibly have more causations such as natural toxins including cyanotoxins, parasitic diseases, industrial chemicals and other anthropogenic contaminants. This study brings new knowledge on the effects of controlled exposure to multiple stressors in birds. The aim was to test the hypothesis that influence of cyanobacterial biomass, lead and antigenic load may combine to enhance the effects on birds, including modulation of antioxidative and detoxification responses. Eight treatment groups of model species Japanese quail (Coturnix coturnix japonica) were exposed to various combinations of these stressors. The parameters of detoxification and oxidative stress were studied in liver and heart after 30 days of exposure. The antioxidative enzymatic defense in birds seems to be activated quite efficiently, which was documented by the elevated levels and activities of antioxidative and detoxification compounds and by the low incidence of damage to lipid membranes. The greatest modulations of glutathione level and activities of glutathione-S-transferase, glutathione peroxidase, glutathione reductase, superoxide dismutase, catalase and lipid peroxidation were shown mostly in the groups with combined multiple exposures. The results indicate that the antioxidative system plays an important role in the protective response of the tissues to applied stressors and that its greater induction helps to protect the birds from more serious damage. Most significant changes of these "defense" parameters in case of multiple stressors suggest activation of this universal mechanism in situation with complex exposure and its crucial role in protection of the bird health in the environment.
- MeSH
- bakteriální toxiny farmakologie MeSH
- biologické markery analýza MeSH
- Coturnix metabolismus virologie MeSH
- glutathion metabolismus MeSH
- glutathionperoxidasa metabolismus MeSH
- glutathionreduktasa metabolismus MeSH
- glutathiontransferasa metabolismus MeSH
- játra účinky léků metabolismus MeSH
- katalasa metabolismus MeSH
- látky reagující s kyselinou thiobarbiturovou metabolismus MeSH
- mikrocystiny farmakologie MeSH
- mořské toxiny farmakologie MeSH
- newcastleská nemoc patofyziologie MeSH
- olovo farmakologie MeSH
- oxidační stres MeSH
- peroxidace lipidů MeSH
- sinice chemie patogenita MeSH
- srdce účinky léků MeSH
- superoxiddismutasa metabolismus MeSH
- virus newcastleské nemoci patogenita MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH