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Pathogens carried by ticks pose a threat to both human and animal health across the world. Typically associated with rural landscapes, ticks appear to adapt well to life in urban recreational areas. Although Dermacentor reticulatus is commonly found across Europe, data on the prevalence of pathogens in this tick species, in an urban environment, are very limited. PCR was used to examine 368 D. reticulatus individuals collected in the Zwierzyniecki Forest Nature Reserve in Bia?ystok, Poland. In total, 10.3% of ticks were infected, with Babesia spp. (9.2%), Anaplasma phagocytophilum (0.8%) and Borrelia burgdorferi sensu lato (0.3%). Rickettsia spp., Bartonella spp., and Coxiella burnetii were not detected. Sequence analysis for Babesia-positive samples identified 79.4% of them as Babesia canis, 8.8% as Babesia microti, 5.9% as Babesia spp., 2.9% as Babesia venatorum, and 2.9% as Babesia vogeli. Results obtained in this study indicate that D. reticulatus ticks found within the urban premises of the study area are infected with at least three pathogens and therefore are an important factor in public health risk for tick-borne diseases.
相似文献A statistical analysis of the variation in contents with the size of the current known smallest genomes, N. deltocephalinicola, C. ruddii, N. equitans, and M. genitalium, enabled the indication of a minimal set of codons capable of naturally building a modern-type free-living unicellular organism in an early stage of evolution. Using a linear regression model, the potential codon distribution in the minimal natural cell was predicted and compared to the composition of the smallest synthetic, JCVI-Syn3.0. The distribution of the molecular weight of potentially coded amino acids was also calculated. The main differences in the features of the minimal natural cell and H. Sapiens genome were analyzed. In this regard, the content percentage of respective amino acids and their polarization charge properties were reported and compared. The fractions of occurring nucleotides were calculated, too. Then, the estimated numbers of codons in a minimal natural cell were related to the expected numbers for random distribution. Shown increase, or decrease in the contents, relative to the calculated random filling was related to the evolutionary preferences, varying with the subsequent eras of the evolution of genetic code.
相似文献Extraintestinal pathogenic Escherichia coli (ExPEC) cause a wide range of clinical diseases such as bacteremia and urinary tract infections. The increase of multidrug resistant ExPEC strains is becoming a major concern for the treatment of these infections and E. coli has been identified as a critical priority pathogen by the WHO. Therefore, the development of vaccines has become increasingly important, with the surface lipopolysaccharide constituting a promising vaccine target. This study presents genetic and structural analysis of clinical urine isolates from Switzerland belonging to the serotype O25. Approximately 75% of these isolates were shown to correspond to the substructure O25B only recently described in an emerging clone of E. coli sequence type 131. To address the high occurrence of O25B in clinical isolates, an O25B glycoconjugate vaccine was prepared using an E. coli glycosylation system. The O antigen cluster was integrated into the genome of E. coli W3110, thereby generating an E. coli strain able to synthesize the O25B polysaccharide on a carrier lipid. The polysaccharide was enzymatically conjugated to specific asparagine side chains of the carrier protein exotoxin A (EPA) of Pseudomonas aeruginosa by the PglB oligosaccharyltransferase from Campylobacter jejuni. Detailed characterization of the O25B-EPA conjugate by use of physicochemical methods including NMR and GC-MS confirmed the O25B polysaccharide structure in the conjugate, opening up the possibility to develop a multivalent E. coli conjugate vaccine containing O25B-EPA.
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