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11.
The objective of this study was to analyse the genetic variability and phylogenetic analysis of six strains of rabbit haemorrhagic disease virus (RHDV), including four Czech strains (CAMPV-351, CAMPV-561, CAMPV-562, CAMPV-558) and two French strains (Fr-1, Fr-2), on the basis of a fragment of the VP60 capsid structural protein-coding gene N-terminal region. The results of our own studies were compared to 26 RHDV strains obtained from GenBank. The analysis of the genetic variability of six RHDV strains indicated that the CAMPV-561 strain is the most genetically variable. Less variable were the Fr-1 and Fr-2 strains, while the least variable was CAMPV-351. In turn, the genetic distance among the six analysed strains and 26 strains obtained from GenBank was the greatest for CAMPV-351 and Whn/China [11.3 % according to the observed divergence (OD) method and 12.2 % according to the maximum likelihood (ML) method], while it was the lowest for CAMPV-351 and FRG (0.8 % in both the OD and ML methods). In turn, the scale of the genetic distances among the six analysed strains and five RHDVa strains (99-05, NY-01, Whn/China, Triptis, Iowa2000) ranged from 9.3–10.3 % in the OD method to 10.3–13.7 % in the ML method. The image of phylogenetic dependencies generated for the strains analysed and those obtained from GenBank revealed their distribution to be in five genetic groups (G1–G5), whereas the analysed strains were included in genetic groups 2 and 3.  相似文献   
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Hereditary nephrotic syndrome is caused by mutations in a number of different genes, the most common being NPHS2. The aim of the study was to identify the spectrum of NPHS2 mutations in Polish patients with the disease. A total of 141 children with steroid-resistant nephrotic syndrome (SRNS) were enrolled in the study. Mutational analysis included the entire coding sequence and intron boundaries of the NPHS2 gene. Restriction fragment length polymorphism (RFLP) and TaqMan genotyping assay were applied to detect selected NPHS2 sequence variants in 575 population-matched controls. Twenty patients (14 %) had homozygous or compound heterozygous NPHS2 mutations, the most frequent being c.1032delT found in 11 children and p.R138Q found in four patients. Carriers of the c.1032delT allele were exclusively found in the Pomeranian (Kashubian) region, suggesting a founder effect origin. The 14 % NPHS2 gene mutation detection rate is similar to that observed in other populations. The heterogeneity of mutations detected in the studied group confirms the requirement of genetic testing the entire NPHS2 coding sequence in Polish patients, with the exception of Kashubs, who should be initially screened for the c.1032delT deletion.  相似文献   
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After a survey of the special role, which the amino acid proline plays in the chemistry of life, the cell‐penetrating properties of polycationic proline‐containing peptides are discussed, and the widely unknown discovery by the Giralt group (J. Am. Chem. Soc. 2002 , 124, 8876) is acknowledged, according to which fluorescein‐labeled tetradecaproline is slowly taken up by rat kidney cells (NRK‐49F). Here, we describe details of our previously mentioned (Chem. Biodiversity 2004 , 1, 1111) observation that a hexa‐β3‐Pro derivative penetrates fibroblast cells, and we present the results of an extensive investigation of oligo‐L ‐ and oligo‐D ‐α‐prolines, as well as of oligo‐β2h‐ and oligo‐β3h‐prolines without and with fluorescence labels ( 1 – 8 ; Fig. 1). Permeation through protein‐free phospholipid bilayers is detected with the nanoFAST biochip technology (Figs. 24). This methodology is applied for the first time for quantitative determination of translocation rates of cell‐penetrating peptides (CPPs) across lipid bilayers. Cell penetration is observed with mouse (3T3) and human foreskin fibroblasts (HFF; Figs. 5 and 68, resp.). The stabilities of oligoprolines in heparin‐stabilized human plasma increase with decreasing chain lengths (Figs. 911). Time‐ and solvent‐dependent CD spectra of most of the oligoprolines (Figs. 13 and 14) show changes that may be interpreted as arising from aggregation, and broadening of the NMR signals with time confirms this assumption.  相似文献   
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Different low-molecular-weight thiols, including glutathione, cysteine, and cysteinylglycine are physiological free radical scavengers. On the other hand, homocysteine may play a role as an oxidant. The aim of our present study was to establish in vitro the effects of the commercial extract of Aronia melanocarpa (Aronox?) on the amount of selected low-molecular-weight thiols and the activity of antioxidative enzymes (superoxide dismutase, glutathione peroxidase, and glutathione reductase) in plasma obtained from patients with invasive breast cancer during different phases of treatment [before or after the surgery and patients after different phases of chemotherapy (doxorubicin and cyclophosphamide)] and from healthy subjects. Patients were hospitalized in Department of Oncological Surgery and Department of Chemotherapy, Medical University of Lodz, Poland. The level of low-molecular-weight thiols was determined by high-performance liquid chromatography. We observed that in the presence of the Aronia extract changes in amount of thiols in plasma from breast cancer patients (at all tested groups) were significantly reduced. Our results showed that tested commercial extract reduced modifications of antioxidative enzymes activity in plasma from patients during different phases of treatment, but this effect was not statistical significant. Our results suggest that the Aronia extract supplementation in breast cancer patients has a beneficial effect on thiols concentration in plasma. Plasma, as reported in this work, could be used as an experimental model to evaluate the beneficial action of plant supplements, including phenolic extracts on thiols or other molecules during different phases of treatment.  相似文献   
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Efficient repair by Escherichia coli AlkB dioxygenase of exocyclic DNA adducts 3,N4-ethenocytosine, 1,N6-ethenoadenine, 3,N4-α-hydroxyethanocytosine, and reported here for the first time 3,N4-α-hydroxypropanocytosine requires higher Fe(II) concentration than the reference 3-methylcytosine. The pH optimum for the repair follows the order of pKa values for protonation of the adduct, suggesting that positively charged substrates favorably interact with the negatively charged carboxylic group of Asp-135 side chain in the enzyme active center. This interaction is supported by molecular modeling, indicating that 1,N6-ethenoadenine and 3,N4-ethenocytosine are bound to AlkB more favorably in their protonated cationic forms. An analysis of the pattern of intermolecular interactions that stabilize the location of the ligand points to a role of Asp-135 in recognition of the adduct in its protonated form. Moreover, ab initio calculations also underline the role of substrate protonation in lowering the free energy barrier of the transition state of epoxidation of the etheno adducts studied. The observed time courses of repair of mixtures of stereoisomers of 3,N4-α-hydroxyethanocytosine or 3,N4-α-hydroxypropanocytosine are unequivocally two-exponential curves, indicating that the respective isomers are repaired by AlkB with different efficiencies. Molecular modeling of these adducts bound by AlkB allowed evaluation of the participation of their possible conformational states in the enzymatic reaction.  相似文献   
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Clustered regularly interspaced short palindromic repeats (CRISPR) are currently a topic of interest in microbiology due to their role as a prokaryotic immune system. Investigations of CRISPR distribution and characterization to date have focused on pathogenic bacteria, while less is known about CRISPR in commensal bacteria, where they may have a significant role in the ecology of the microbiota of humans and other animals, and act as a recorder of interactions between bacteria and viruses. A combination of PCR and sequencing was used to determine prevalence and distribution of CRISPR arrays in Enterococcus faecalis and Enterococcus hirae isolates from the feces of healthy pigs. Both type II CRISPR–Cas and Orphan CRISPR (without Cas genes) were detected in the 195 isolates examined. CRISPR–Cas was detected in 52 (46/88) and 42 % (45/107) E. faecalis and E. hirae isolates, respectively. The prevalence of Orphan CRISPR arrays was higher in E. faecalis isolates (95 %, 84/88) compared with E. hirae isolates (49 %, 53/107). Species-specific repeat sequences were identified in Orphan CRISPR arrays, and 42 unique spacer sequences were identified. Only two spacers matched previously characterized pig virome sequences, and many were apparently derived from chromosomal sequences of enterococci. Surprisingly, 17 (40 %) of the spacers were detected in both species. Shared spacer sequences are evidence of a lack of species specificity in the agents and mechanisms responsible for integration of spacers, and the abundance of spacer sequences corresponding to bacterial chromosomal sequences reflects interspecific interactions within the intestinal microbiota.  相似文献   
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