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Enterococcus faecalis represents recently an important etiological agent of health care-associated infections (HAIs) and there is a need for evaluation and comparison of typing methods available for this microorganism. We tested multilocus VNTR (variable-number tandem repeats) analysis (MLVA) on a well-characterized collection of 153 clinical isolates of E. faecalis, corresponding to 52 multilocus sequence types and 67 pulsed-field gel electrophoresis (PFGE) profiles. MLVA showed high discriminatory power, discerning 111 different types (diversity index equal 98.9%). The concordance MLVA/MLST and MLVA/PFGE was 0.95 and 0.74, respectively. High discriminatory power of MLVA indicates its utility for local epidemiology such as outbreak investigation, and for differentiation of clones defined by other methods.
The aim of the study was the evaluation and optimisation of PCR test for the detection of dermonecrotoxin gene (DNT) of Bordetella bronchiseptica. For the optimisation of the test, vaccine strain B16 was used. The optimisation procedure included: estimation of optimal Mg²⁺ concentration, annealing temperature, numbers of cycles, as well as sensitivity. The specificity of PCR test was checked with DNA of other pathogens existing in pigs' respiratory tract. The elaborated test was specific and sensitive to detect DNT gene of B. bronchiseptica, in both clinical samples, as well as in pure culture of the bacteria.
Coxiella burnetii is the etiologie agent of Q fever, a worldwide distributed zoonosis, accountable for serious health problem both for humans and animals. The exposure to C. burnetii infected animals and their products is the main risk factor for Q fever in humans. Several outbreaks of Q fever have been described in Poland which sources were recognized to be related to imported animals and their products or to wildlife using serological methods. Moreover, some of them have been confinned by isolation of C. burnetii strains. In this study, multispacer sequence typing (MST) and multiple loci variable number tandem repeats (VNTR) analysis (MLVA) have been used to characterize C. burnetii strains isolated in Poland. A total of two sequence types (MST) and four MLVA types were identified among 6 C. burnetii isolates examined. This study highlighted the usefulness of these methods in the improvement of epidemiological investigations of Q fever loci on the Polish territory.
Urinary tract infections are a very serious health and economic problem affecting millions of people each year worldwide. The most common etiologic agent of this type of bacterial infections, involving the upper and lower urinary tract, are E. coli strains representing approximately 80% of cases. Uropathogenic E. coli strains produce several urovirulence factors which can be divided into two main types, surface virulence factors and exported virulence factors. Surface-exposed structures include mainly extracellular adhesive organelles such as fimbriae/pili necessary in adhesion, invasion, biofilm formation and cytokine induction. Among the surface-exposed polymeric adhesive structures there are three most invasive groups, type 1 pili, type P pili and Dr family of adhesins which are bioassembled via the conserved, among Gram-negative bacteria, chaperone-usher secretion system. Type 1 and P-piliated E. coli cause cystitis and pyelonephritis. The Dr family of adhesins recognizing DAF receptor is responsible for cystitis, pyelonephritis (especially in pregnant women) and diarrhoea (in infants). In addition, Dr-positive E. coli strains carry the risk of recurrent urinary tract infections. Pyelonephritis in pregnant women leads to a series of complications such as bacteremia, urosepsis, acute respiratory distress syndrome and even death. In the era of increasing drug resistance of bacteria, the development of vaccines, drugs termed pilicides and inhibitors of adhesion may be a promising tool in the fight against urogenital infections.
The purpose of the study was to determine the etiological mastitis agents in cows from herds located in the western part of Poland in years 2003-2005. Bacteriological examinations of 18,713 samples taken from California Mastitis Test (CMT) positive quarters were performed according to standard methods. Some Gram-negative bacilli and Gram-positive cocci were examined with the use of API tests (Analytical Profile Index). It was found that 32.7% of samples that were CMT positive were culture negative and 9.3% of samples were contaminated. Streptococcus species (15.7%), coagu- lase negative staphylococci (CNS) (14.6%), Staph, aureus (8.6%), Gram-negative bacilli (4.0%) and Corynebacterium species (3.8%) were most frequently isolated. Escherichia coli (52.3%) dominated among Gram-negative bacilli followed by Klebsiella pneumoniae (4.1%), Pseudomonas aeruginosa (3.6%), Enterobacter cloacae (3.6%), Serratia marcescens (3.1%), Pasteurella multocida (3.1%), Acinetobacter Iwofii (3.1%), and 26 other bacteria species. Stahylococcus xylosus (31.5%), Staph, hyicus (12.2%), Staph, haemolyticus (12.2%), Staph, sciuri (11.6%), Staph, chromogenes (8.8%), Staph, epidermidis (8.3%) and Staph, simulans (6.1%) were the most frequent CNS. Streptococcus uberis (50%), Str. dysgalactiae (19.7%), Str. acidominimus (6.6%) and Enterococcus faecalis (5.3%) were mostly found among CAMP-negative streptococci. An increase in frequency of mastitis caused by non-agalactiae streptococci, Staph, aureus, A. pyogenes and yeast-like fungi and a decrease in that produced by Str. agalactiae in 2005 as compared to years 2003 or 2004 were observed.
Borrelia burgdorferi sensu lato, the etiologic agent of Lyme borreliosis, circulates between ticks and vertebrate hosts. Two main genospecies typically occur in the Czech Republic Borrelia garinii and Borrelia afzelii, transmitted generally by Ixodes ricinus (L., 1758) ticks. The aim of our study was to identify spirochaete isolates focusing on Borrelia burgdorferi acquired from different sources: vectors (ticks), potential vectors (mosquitoes, small mites) and hosts (wild rodents). In the years 1996–2001 a total of 2398 ticks, 72 mites (from wild rodents), 2700 mosquito adults, 1798 mosquito larvae and organ parts (kidney and spleen) of 216 wild rodents were collected from seven localities in the Czech Republic. A total of 31 spirochaete strains were isolated: 13 strains from ticks, 1 strain from mite (Haemogamasus sp.), 15 strains from rodents, 1 strain from mosquito adults and 1 strain from mosquito larva. For the genospecies identification of these isolates PCR, PCR-RFLP was used and their characterization was also performed by SDS-PAGE. By nested PCR method all except one isolated strains were detected as Borrelia burgdorferi s.l. Following PCR-RFLP molecular analysis results, tick isolates were identified as B. garinii and B. afzelii, the strain isolated from the mite was identified as B. afzelii. This is the first isolated strain of B.b.s.l. from a different mite of infraorder Parasitiformes than tick. All of rodent isolates were identified as B. afzelii; mosquito adult isolate was identified as B. afzelii. Larval isolate from mosquito is spirochaete, but does not belong to Borrelia burgdorferi sensu lato group.
The paper describes the occurence of Flavobacterium psychrophilum as a concurrent pathogen with infectious hematopoietic necrosis virus in rainbow trout fry in Croatia. A molecular technique was applied for F. psychrophilum detection due to the failure of standard bacterial identification on agar plates. As the tissue material had already been used up for RNA extraction and detection of RNA virus, classical, well-described PCR could not be performed. Consequently, one step RT-PCR was adapted for F. psychrophilum identification. This method proved to be a valuable diagnostic tool for F. psychrophilum detection in mixed co-infections with RNA viruses.
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