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81.
The aim of this study was to identify the factors determining the incidence of Lyme borreliosis (LB) in south‐western Poland by estimating the prevalence of B. burgdorferi s. l. in I. ricinus, and to analyze the temporal abundance of ticks in relation to epidemiological data on LB incidence. Host‐seeking ticks collected in 2011 in four districts in southwestern Poland were examined by nested PCR for the presence of B. burgdorferi s.l. In total, 2,507 host‐seeking I. ricinus were collected. The temporal abundance of ticks varied between districts. The minimal infection rates with B. burgdorferi s.l. were 11.5% for nymphs and 37.7% for adults. There were no statistical differences in the level of infection between districts either for nymphs or for adults. Five different genospecies were identified within the B. burgdorferi s.l. complex: B. garinii, B. afzelii, B. lusitaniae, B. valasiana, and B. burgdorferi s.s., and additionally B. miyamotoi. Our results point to a relationship between tick temporal abundance and LB incidence both for adults and nymphs. The high abundance of ticks is positively correlated with the number of LB cases in humans. The tick's abundance may be considered as a major factor in determining the LB risk in southwestern Poland. 相似文献
82.
A. R. Clausen A. Matakos M. P. B. Sandrini J. Piškur 《Nucleosides, nucleotides & nucleic acids》2013,32(9-11):1159-1163
Twenty-six fully sequenced archaeal genomes were searched for genes coding for putative deoxyribonucleoside kinases (dNKs). We identified only 5 human-like thymidine kinase 1 genes (TK1s) and none for non-TK1 kinases. Four TK1s were identified in the Euryarchaea and one was found in the Crenarchaea, while none was found in Nanoarchaeum. The identified TK1s have high identity to Gram-positive bacteria TK1s. The TK1s from archaea, Gram-positive bacteria and eukaryotes share the same common ancestor, while the TK1s from Gram-negative bacteria belong to a less-related subgroup. It seems that a functional deoxyribonucleoside salvage pathway is not crucial for the archaeal cell. 相似文献
83.
Śárka Králíková Miloś Buděšínský Milena Masojídková Ivan Rosenberg 《Nucleosides, nucleotides & nucleic acids》2013,32(7):1159-1183
Abstract In this report we present a novel, simple way for the synthesis of 3′-C-phosphonate derivatives of all four basic 2′-deoxynucleosides in both fully protected and deprotected forms. The reactivity of the geminal hydroxy phosphonate moiety located at the 3′-carbon atom of the nucleoside was studied with respect to the use of this type of nucleoside phosphonic acid for the preparation of short oligonucleotides, namely, dinucleoside monophosphate analogues. 相似文献
84.
Dijana Saftić Ljubica Glavaš-Obrovac Mirosława Studzińska Edyta Paradowska Zbigniew J. Leśnikowski 《Nucleosides, nucleotides & nucleic acids》2013,32(7):397-414
AbstractAs a part of the research aimed on identification of new nucleobase derivatives with improved biological properties, a series of novel 8-substituted acyclovir derivatives were synthesized. The 8-azidoguanosine 4 and novel 8-azidoacyclovir 9 were synthesized from commercially available guanosine 1 and acyclovir 6 which were transformed into 8-bromopurine derivatives 2 and 7 and hydrazine derivatives 3 and 8, respectively. 8-Triazolylguanosine 5 and 8-triazolylacyclovir analogs 10–12 were successfully synthesized via the Cu(I) catalyzed 1,3-dipolar cycloaddition reaction of azides 4 and 9 with propargyl alcohol, 4-pentyn-1-ol and 5-hexyn-1-ol. The novel 1,4-disubstituted 1,2,3-triazolyl compounds 5, 10–12 were evaluated for antiviral activity against selected DNA and RNA viruses and cytostatic activity against normal Madine Darby canine kidney (MDCK I) cells, and seven tumor cell lines (HeLa, CaCo-2, NCI-H358, Jurkat, K562, Raji and HuT78). While tested compounds exerted no antiviral activity at nontoxic concentrations, the 8-triazolyl acyclovir derivative 10, with the shortest alkyl substituent at the C-4 of triazole ring, was found to be the most active against the CaCo-2 cell line. 相似文献
85.
86.
Ł. Grześkowiak A. Endo M.C. Collado L.J. Pelliniemi S. Beasley S. Salminen 《Journal of applied microbiology》2013,115(2):539-545
Aims
The manufacturing processes have been reported to influence the properties of probiotics with potential impact on health properties. The aim was to investigate the effect of different growth media and inactivation methods on the properties of canine‐originated probiotic bacteria alone and in combination mixture.Methods and Results
Three established dog probiotics, Lactobacillus fermentum VET9A, Lactobacillus plantarum VET14A and Lactobacillus rhamnosus VET16A, and their combination mixture were evaluated for their adhesion to dog mucus. The effect of different growth media, one reflecting laboratory and the other manufacturing conditions, and inactivation methods (95°C, 80°C and UV irradiation) on the mucus adhesion of the probiotic strains was characterized. Evaluation of dog probiotics was supported by cell visualization using transmission electron microscopy (TEM). Higher adhesion percentage was reported for probiotic strains growing in laboratory rather than in manufacturing conditions (P < 0·05). Inactivation by heat (95°C, 80°C) decreased the adhesion properties when strains were cultivated in soy‐based growth media compared with those grown in MRS broth (P < 0·05). TEM observations uncovered differences in cell‐surface components in nonviable forms of probiotic strains as compared with their viable forms.Conclusions
Manufacturing process conditions such as growth media and pretreatment methods may significantly affect the adhesive ability of the tested strains.Significance and Impact of the Study
Growth conditions, growth media, pretreatment methods and different probiotic combinations should be carefully considered for quality control of existing probiotics and for identification of new probiotics for dogs. These may also have an impact on health benefits for the host. 相似文献87.
Background and Aims
Solving relationships of recently diverged taxa, poses a challenge due to shared polymorphism and weak reproductive barriers. Multiple lines of evidence are needed to identify independently evolving lineages. This is especially true of long-lived species with large effective population sizes, and slow rates of lineage sorting. North American pines are an interesting group to test this multiple approach. Our aim is to combine cytoplasmic genetic markers with environmental information to clarify species boundaries and relationships of the species complex of Pinus flexilis, Pinus ayacahuite, and Pinus strobiformis.Methods
Mitochondrial and chloroplast sequences were combined with previously obtained microsatellite data and contrasted with environmental information to reconstruct phylogenetic relationships of the species complex. Ecological niche models were compared to test if ecological divergence is significant among species.Key Results and Conclusion
Separately, both genetic and ecological evidence support a clear differentiation of all three species but with different topology, but also reveal an ancestral contact zone between P. strobiformis and P. ayacahuite. The marked ecological differentiation of P. flexilis suggests that ecological speciation has occurred in this lineage, but this is not reflected in neutral markers. The inclusion of environmental traits in phylogenetic reconstruction improved the resolution of internal branches. We suggest that combining environmental and genetic information would be useful for species delimitation and phylogenetic studies in other recently diverged species complexes. 相似文献88.
Ji?í Dvo?ák Veronika Man?íková Václav Pi?l Dana Elhottová Marcela ?ilerová Radka Roubalová Franti?ek ?kanta Petra Procházková Martin Bilej 《PloS one》2013,8(11)
Survival of earthworms in the environment depends on their ability to recognize and eliminate potential pathogens. This work is aimed to compare the innate defense mechanisms of two closely related earthworm species, Eisenia andrei and Eisenia fetida, that inhabit substantially different ecological niches. While E. andrei lives in a compost and manure, E. fetida can be found in the litter layer in forests. Therefore, the influence of environment-specific microbiota on the immune response of both species was followed. Firstly, a reliable method to discern between E. andrei and E. fetida based on species-specific primers for cytochrome c oxidase I (COI) and stringent PCR conditions was developed. Secondly, to analyze the immunological profile in both earthworm species, the activity and expression of lysozyme, pattern recognition protein CCF, and antimicrobial proteins with hemolytic function, fetidin and lysenins, have been assessed. Whereas, CCF and lysozyme showed only slight differences in the expression and activity, fetidin/lysenins expression as well as the hemolytic activity was considerably higher in E. andrei as compared to E. fetida. The expression of fetidin/lysenins in E. fetida was not affected upon the challenge with compost microbiota, suggesting more substantial changes in the regulation of the gene expression. Genomic DNA analyses revealed significantly higher level of fetidin/lysenins (determined using universal primer pairs) in E. andrei compared to E. fetida. It can be hypothesized that E. andrei colonizing compost as a new habitat acquired an evolutionary selection advantage resulting in a higher expression of antimicrobial proteins. 相似文献
89.
The p53 protein is a key player in cell response to stress events and cancer prevention. However, up-regulation of p53 that occurs during radiotherapy of some tumours results in radio-resistance of targeted cells. Recently, antisense oligonucleotides have been used to reduce the p53 level in tumour cells which facilitates their radiation-induced apoptosis. Here we describe the rational design of antisense oligomers directed against the 5′-terminal region of p53 mRNA aimed to inhibit the synthesis of p53 protein and its ΔNp53 isoform. A comprehensive analysis of the sites accessible to oligomer hybridization in this mRNA region was performed. Subsequently, translation efficiency from the initiation codons for both proteins in the presence of selected oligomers was determined in rabbit reticulocyte lysate and in MCF-7 cells. The antisense oligomers with 2′-OMe and LNA modifications were used to study the mechanism of their impact on translation. It turned out that the remaining RNase H activity of the lysate contributed to modulation of protein synthesis efficiency which was observed in the presence of antisense oligomers. A possibility of changing the ratio of the newly synthetized p53 and ΔNp53 in a controlled manner was revealed which is potentially very attractive considering the relationship between the functioning of these two proteins. Selected antisense oligonucleotides which were designed based on accessibility mapping of the 5′-terminal region of p53 mRNA were able to significantly reduce the level of p53 protein in MCF-7 cells. One of these oligomers might be used in the future as a support treatment in anticancer therapy. 相似文献
90.
M. Korja M. Ylijoki H. Lapinleimu P. Pohjola J. Matomäki H. Kuśmierek M. Mahlman H. Rikalainen R. Parkkola T. Kaukola L. Lehtonen M. Hallman L. Haataja 《Genes, Brain & Behavior》2013,12(3):348-352
Apolipoprotein E plays an important role in neurodegenerative processes in adulthood, whereas its neurodevelopmental role is uncertain. We aimed to study the effect of apolipoprotein E on neurodevelopment in a cohort liable to neurodevelopmental changes. The cohort consisted of very preterm (<32 gestational weeks) and/or very low birth weight (<1500 g) children, and the longitudinal follow‐up protocol included sequential cranial ultrasounds during infancy, brain magnetic resonance imaging at term‐equivalent age, neurological and cognitive assessment (Mental Developmental Index) at the corrected age of 2 years and cognitive and neuropsychological assessments (Wechsler Preschool and Primary Scale of Intelligence and Developmental NEuroPSYchological Assessment) at the chronological age of 5 years. Apolipoprotein E genotypes were determined from 322 children. Ultrasound and magnetic resonance imaging data were available for 321 (99.7%) and 151 (46.9%) children, respectively. Neurodevelopmental assessment data were available for 138 (42.9%) to 171 (53.1%) children. Abnormal findings in ultrasounds and magnetic resonance imaging were found in 163 (50.8%) and 64 (42.4%) children, respectively. Mild cognitive delay at the corrected age of 2 years and the chronological age of 5 years was suspected in 21 (12.3%) of 171 and 19 (13.8%) of 138 children, respectively. In the Developmental NEuroPSYchological Assessment, 47 (32.6%) of 144 children had significantly impaired performances in more than one study subtest. No associations between the apolipoprotein E genotypes and imaging findings or measured neurodevelopmental variables were found. Apolipoprotein E genotypes do not appear to have major impact on brain vulnerability or neurodevelopment in children . 相似文献