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This paper reports the analysis of the nucleotide sequences of the 5'-untranslated region (5'-UTR) of tick-borne encephalitis virus (TBEV) genomic RNA isolated from 39 individual taiga ticks ...collected in several regions of Northern Eurasia. The sequences of 5'-UTRs of the Siberian and Far East TBEV genotypes were 89% and 95% identical to the prototype strains (Zausaev and 205), respectively. The detected nucleotide substitutions were typical for these two TBEV genotypes, which made possible unambiguous identification. Both conservative and variable motifs were detected in the 5'-UTR RNA. The B2, C1, and C2 elements of the Y-shaped 5'-UTR structure and the presumable viral RNA-dependent RNA-polymerase binding site were the most variable. The A2, CS A, CS B elements as well as the start codon were conservative. Interestingly, five substitutions in the 5'-UTR C1 variable element of the TBEVs isolated in different geographical regions were strictly conservative, while 11 different substitutions were detected in this element among the laboratory TBEV variants. A little less that a third of all nucleotide substitutions were mapped outside the main elements of the Y-shaped structure. In general, nucleotide substitutions were localized to stem structures, not being found in the hairpin regions of the TBEV 5'-UTR. The results indicated significant variability of the genomic RNA 5'-UTR in the TBEV laboratory strains and field isolates obtained from different geographical regions. It has been suggested that genetic variability of 5'-UTR is characteristic of the TBEV genome 5'-UTR organization and may serve as a structural basis for virus efficient replication in various avian, mammalian, and ixodic tick cells.
The objectives of our study were to survey the prevalence of genetic markers for Rickettsia spp., Ehrlichia spp., Anaplasma spp., Babesia spp., and Theileria spp. in Hyalomma anatolicum ticks ...collected in southwestern Tajikistan and to perform sequencing and phylogenetic analysis of fragments of the 16S rRNA gene and groESL operon from Ehrlichia spp. and fragments of the 18S rRNA gene of Theileria spp. detected in H. anatolicum ticks. Hyalomma anatolicum ticks collected in the Tursunzade and Rudaki districts of Tajikistan were tested for DNA of Rickettsia spp., Ehrlichia spp., Anaplasma spp., Babesia spp., and Theileria spp. by PCR with specific primers. The amplified fragments were sequenced and analyzed. DNA of Ehrlichia spp. (3.3 %) and Theileria spp. (3.3 %) was detected only in H. anatolicum ticks collected from the Rudaki district, and DNA of Ehrlichia spp. (0.7 %) was found in H. anatolicum ticks from the Tursunzade district. Sequence analysis of fragments of the 16S rRNA gene and groESL operon from Ehrlichia spp. revealed high similarity to Ehrlichia spp. The Tajik isolates of Theileria spp. were genotyped as Theileria annulata based on the analysis of 18S rRNA gene sequences. The phylogenetic analysis demonstrates that Ehrlichia spp. isolates are highly similar to Ehrlichia spp. circulating in China and Brazil. The isolate Tajikistan-5 is closely related to the putative novel species Ehrlichia mineirensis. The Tajik isolates of Theileria spp. were clustered with T. annulata isolates from Turkey, Iran, Pakistan, and China by phylogenetic analyses.
Primary cilium dysfunction underlies the pathogenesis of Bardet-Biedl syndrome (BBS), a genetic disorder whose symptoms include obesity, retinal degeneration, and nephropathy. However, despite the ...identification of 12 BBS genes, the molecular basis of BBS remains elusive. Here we identify a complex composed of seven highly conserved BBS proteins. This complex, the BBSome, localizes to nonmembranous centriolar satellites in the cytoplasm but also to the membrane of the cilium. Interestingly, the BBSome is required for ciliogenesis but is dispensable for centriolar satellite function. This ciliogenic function is mediated in part by the Rab8 GDP/GTP exchange factor, which localizes to the basal body and contacts the BBSome. Strikingly, Rab8GTP enters the primary cilium and promotes extension of the ciliary membrane. Conversely, preventing Rab8GTP production blocks ciliation in cells and yields characteristic BBS phenotypes in zebrafish. Our data reveal that BBS may be caused by defects in vesicular transport to the cilium.
A theoretical analysis is presented on possible effects of disorder by dopants in high-temperature superconducting cuprate perovskites, to define their basic spectra of spin and electronic ...excitations, and the subsequent observable properties, especially doping dependence of superconducting order parameter. The central point in the proposed physical picture is formation of specific impurity subband within the insulating bandgap of initial undoped material, serving as a source for the system metallization and further transition into superconducting state with anisotropic order parameter.
Effects of impurities and disorder on transport properties by electronic quasiparticles in superconducting iron pnictides are theoretically considered. The most prominent new features compared to the ...case of pure material should appear at high enough impurity concentration when a specific narrow band of conducting quasiparticle states can develop within the superconducting gap, around the position of localized impurity level by a single impurity center. The predicted specific threshold effects in the frequency-dependent optical conductivity and temperature-dependent thermal conductivity and also in Seebeck and Peltier coefficients can have interesting potentialities for practical applications.
In this work, the study of dielectric properties of composite structures on the base of poly(vinylidene fluoride-triflouroethylene) copolymer P(VDF-TrFE) and porous aluminum oxide layers produced by ...the melt-impregnation is presented. Frequency dependences of dielectric characteristics of the composite samples were determined. The dielectric dispersion and ferroelectric switching processes in the composite structures were discussed.
In this work we tested two reagent kits developed by us for detecting SARS-CoV-2 RNA using a fragment of the ORF1ab gene in digital PCR and real-time PCR formats. Data were obtained on the detection ...of SARS-CoV-2 virus RNA in nasopharyngeal swabs of patients with COVID-19 and asymptomatic carriers. The developed reagent kits provided 100% sensitivity and a detection limit of 103 GE / ml for qPCR, and at least 200 copies / ml of viral RNA when performing digital PCR. These methods were tested using a panel of 1,328 samples collected from patients with suspected COVID-19 at the beginning of 2020 in the Russian Federation. It has been shown that dPCR is more sensitive and can be used to analyze samples with low viral load, including those from patients without clinical symptoms. dPCR significantly improves the accuracy of laboratory research and significantly reduces the number of false negative results in the diagnosis of SARS-CoV-2. Determination of the concentration of SARS-CoV-2 RNA in patients with different clinical course of the disease showed that the concentration of viral RNA can sharply decrease in the first days of the disease. A low concentration of viral RNA in samples from patients is also characteristic of asymptomatic disease. Digital PCR provides a higher detection rate for asymptomatic cases, which is approximately 75% of those infected, as opposed to 45% for real-time PCR. The results obtained on the use of the digital PCR method for detecting SARS-CoV-2 RNA showed that this method is especially suitable for detecting RNA in case of its low concentration in contacts, as well as for monitoring changes in viral load in convalescent patients.
Spin-torque effects in antiferromagnetic (AFM) materials are of great interest due to the possible applications as high-speed spintronic devices. In the present paper we analyze the statistical ...properties of the current-driven AFM nanooscillator that result from the white Gaussian noise of magnetic nature. According to the peculiarities of deterministic dynamics, we derive the Langevin and Fokker-Planck equations in the energy representation of two normal modes. We find the stationary distribution function in the subcritical and overcritical regimes and calculate the current dependence of the average energy, energy fluctuation and their ratio (quality factor). The noncritical mode shows the Boltzmann statistics with the current-dependent effective temperature in the whole range of the current values. The effective temperature of the other, i.e., soft, mode critically depends on the current in the subcritical region. Distribution function of the soft mode follows the Gaussian law above the generation threshold. In the overcritical regime, the total average energy and the quality factor grow with the current value. This raises the AFM nanooscillators to the promising candidates for active spintronic components.
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