34 research outputs found
Highly Effective xMAP Multiplex Assay for the Detection and Identification of Hemorrhagic Fever Agents, Including Ebola Virus
Developed has been the oligonucleotide liquid biochip based on xMAP technology, designed for the laboratory detection of particularly dangerous viral pathogens such as Ebola and Marburg filoviruses, and Machupo , Junin, and Lassa arenaviruses. The suggested approach allows for the detection of up to 100 viral genome equivalents in a sample. The sensitivity and specificity of oligonucleotide biochip is 100 % when the laboratory panels of positive and negative samples are used. These results indicate that the xMAP multiplexing for the detection and identification of tropical hemorrhagic fever agents, including Ebola virus, is not inferior to the conventional method such as real-time RT-PCR and can be applied for evaluation of viral load, and further on can easily be expanded for both the analysis of new viral agents and for the detection of critical mutations in viral genomes
Genotypes and Subtypes of Hepatitis B Virus Isolates in the Territory of Siberia
Identified are the occurrence, serotypic and genotypic variations of Hepatitis B virus isolates (HBV) among the Novosibirsk region inhabitants (n=2000), native population of the Alarsk District of the Irkutsk Region (n=487) and Shuryshkarsk Township of the Yamalo-Nenets Autonomous District (n=657). Occurrence rate of hepatitis В surface antigen (HBsAg) among different groups of the Novosibirsk Region population varied within the limits of 3,6-35,0 %. It was 8,2 % in Alarsk District, and 3,2 % in Shuryshkarsk Township. HBV isolates of D genotype (92-97 %) prevail among the population of Siberia; few are the cases of A (1,7 %) and C (1,2-8 %) genotypes. The identified varying occurrence of HBV sub-genotypes and HBsAg subtypes in two aboriginal groups of Siberia (D3 sub-genotype and ayw2 subtype - in the Alarsk District, D2 and ayw3 - in Shuryshkarsk Township) suggests the existence of, at least, two isolated HBV virus populations, circulating among different groups of Siberia native population
Dry and Humid Periods Reconstructed from Tree Rings in the Former Territory of Sogdiana (Central Asia) and Their Socio-economic Consequences over the Last Millennium
One of the richest societies along the Silk Road developed in Sogdiana,
located in present-day Tajikistan, Uzbekistan, and Kyrgyzstan. This urban civilisation
reached its greatest prosperity during the golden age of the Silk Road (sixth to
ninth century ce). Rapid political and economic changes, accelerated by climatic
variations, were observed during last millennium in this region. The newly developed
tree-ring-based reconstruction of precipitation for the pastmillennium revealed
a series of dry and wet stages. During the Medieval Climate Anomaly (MCA), two
dry periods occurred (900–1000 and 1200–1250), interrupted by a phase of wetter
conditions. Distinct dry periods occurred around 1510–1650, 1750–1850, and
1920–1970, respectively. The juniper tree-ring record of moisture changes revealed
that major dry and pluvial episodes were consistent with those indicated by hydroclimatic
proxy data from adjacent areas. These climate fluctuations have had longand
short term consequences for human history in the territory of former Sogdiana
Assimilating Seizure Dynamics
Observability of a dynamical system requires an understanding of its state—the collective values of its variables. However, existing techniques are too limited to measure all but a small fraction of the physical variables and parameters of neuronal networks. We constructed models of the biophysical properties of neuronal membrane, synaptic, and microenvironment dynamics, and incorporated them into a model-based predictor-controller framework from modern control theory. We demonstrate that it is now possible to meaningfully estimate the dynamics of small neuronal networks using as few as a single measured variable. Specifically, we assimilate noisy membrane potential measurements from individual hippocampal neurons to reconstruct the dynamics of networks of these cells, their extracellular microenvironment, and the activities of different neuronal types during seizures. We use reconstruction to account for unmeasured parts of the neuronal system, relating micro-domain metabolic processes to cellular excitability, and validate the reconstruction of cellular dynamical interactions against actual measurements. Data assimilation, the fusing of measurement with computational models, has significant potential to improve the way we observe and understand brain dynamics
FULL-LENGTH PEPTIDE ASSAY OF ANTIGENIC PROFILE OF ENVELOPE PROTEINS FROM SIBERIAN ISOLATES OF HEPATITIS C VIRUS
Antigenic profiles of envelope glycoproteins of hepatitis C virus presented by three genotypes 1b, 2a/2c and 3a, which are most widespread in the territory of Russia and, in particular, in Novosibirsk, were studied using a panel of overlapping synthetic peptides. It was shown that highly immunogenic peptide epitopes of Е1 and Е2 proteins common for all HCV genotypes, are located in amino acid positions 250-260, 315-325 (Е1 protein), 390-400 (hypervariable region 1), 430-440, and 680-690 (Е2 protein). The greatest inter-genotypic differences were recorded in positions 280-290, 410-430 and 520-540. A novel antigenic determinant was detected in the region of aa 280-290 of the Е1 protein which was typical only for HCV 2a/2c genotype. A broad variation in the boundaries for the most epitopes suggests a high variability of the Е1 and Е2 viral proteins; however, a similar repertoire of antibodies induced by different HCV genotypes indicates to an opportunity of designing a new generation of cross-reactive HCV vaccines based on mapping of the E1 and E2 antigenic regions