23 research outputs found

    Field Conservation of Archaeological Textile Artefacts as a Preparatory Stage For Laboratory Restoration

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    Archaeological textile finds are rare due to their poor preservation state. Unearthed and recorded textile artefacts or their fragments often simply do not reach the restoration stage as they are destroyed during burial cleaning, removal from the soil, or during transportation. The use of field conservation methods allows for preservation and relatively painless extraction of fragile textile fragments, with delivery to a stationary resto­ration laboratory without further damage. All field conservation methods are temporary measures. The paper describes a method of field conservation of textile from a certain archaeological site using a low molecular weight solution of polyethylene glycol (PEG-200) and antiseptic Lysoformin-3000 in situ from the moment of discovery to the allocation of finds to a permanent storage facility

    Large family with both parents affected by distinct BRCA1 mutations: implications for genetic testing

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    Although the probability of both parents being affected by BRCA1 mutations is not negligible, such families have not been systematically described in the literature. Here we present a large breast-ovarian cancer family, where 3 sisters and 1 half-sister inherited maternal BRCA1 5382insC mutation while the remaining 2 sisters carried paternal BRCA1 1629delC allele. No BRCA1 homozygous mutations has been detected, that is consistent with the data on lethality of BRCA1 knockout mice. This report exemplifies that the identification of a single cancer-predisposing mutation within the index patient may not be sufficient in some circumstances. Ideally, all family members affected by breast or ovarian tumor disease have to be subjected to the DNA testing, and failure to detect the mutation in any of them calls for the search of the second cancer-associated allele

    High frequency of BRCA1, but not CHEK2 or NBS1 (NBN), founder mutations in Russian ovarian cancer patients

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    <p>Abstract</p> <p>Background</p> <p>A significant portion of ovarian cancer (OC) cases is caused by germ-line mutations in BRCA1 or BRCA2 genes. BRCA testing is cheap in populations with founder effect and therefore recommended for all patients with OC diagnosis. Recurrent mutations constitute the vast majority of BRCA defects in Russia, however their impact in OC morbidity has not been yet systematically studied. Furthermore, Russian population is characterized by a relatively high frequency of CHEK2 and NBS1 (NBN) heterozygotes, but it remains unclear whether these two genes contribute to the OC risk.</p> <p>Methods</p> <p>The study included 354 OC patients from 2 distinct, geographically remote regions (290 from North-Western Russia (St.-Petersburg) and 64 from the south of the country (Krasnodar)). DNA samples were tested by allele-specific PCR for the presence of 8 founder mutations (BRCA1 5382insC, BRCA1 4153delA, BRCA1 185delAG, BRCA1 300T>G, BRCA2 6174delT, CHEK2 1100delC, CHEK2 IVS2+1G>A, NBS1 657del5). In addition, literature data on the occurrence of BRCA1, BRCA2, CHEK2 and NBS1 mutations in non-selected ovarian cancer patients were reviewed.</p> <p>Results</p> <p>BRCA1 5382insC allele was detected in 28/290 (9.7%) OC cases from the North-West and 11/64 (17.2%) OC patients from the South of Russia. In addition, 4 BRCA1 185delAG, 2 BRCA1 4153delA, 1 BRCA2 6174delT, 2 CHEK2 1100delC and 1 NBS1 657del5 mutation were detected. 1 patient from Krasnodar was heterozygous for both BRCA1 5382insC and NBS1 657del5 variants.</p> <p>Conclusion</p> <p>Founder BRCA1 mutations, especially BRCA1 5382insC variant, are responsible for substantial share of OC morbidity in Russia, therefore DNA testing has to be considered for every OC patient of Russian origin. Taken together with literature data, this study does not support the contribution of CHEK2 in OC risk, while the role of NBS1 heterozygosity may require further clarification.</p

    Imaging Single Retrovirus Entry through Alternative Receptor Isoforms and Intermediates of Virus-Endosome Fusion

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    A large group of viruses rely on low pH to activate their fusion proteins that merge the viral envelope with an endosomal membrane, releasing the viral nucleocapsid. A critical barrier to understanding these events has been the lack of approaches to study virus-cell membrane fusion within acidic endosomes, the natural sites of virus nucleocapsid capsid entry into the cytosol. Here we have investigated these events using the highly tractable subgroup A avian sarcoma and leukosis virus envelope glycoprotein (EnvA)-TVA receptor system. Through labeling EnvA pseudotyped viruses with a pH-sensitive fluorescent marker, we imaged their entry into mildly acidic compartments. We found that cells expressing the transmembrane receptor (TVA950) internalized the virus much faster than those expressing the GPI-anchored receptor isoform (TVA800). Surprisingly, TVA800 did not accelerate virus uptake compared to cells lacking the receptor. Subsequent steps of virus entry were visualized by incorporating a small viral content marker that was released into the cytosol as a result of fusion. EnvA-dependent fusion with TVA800-expressing cells occurred shortly after endocytosis and delivery into acidic endosomes, whereas fusion of viruses internalized through TVA950 was delayed. In the latter case, a relatively stable hemifusion-like intermediate preceded the fusion pore opening. The apparent size and stability of nascent fusion pores depended on the TVA isoforms and their expression levels, with TVA950 supporting more robust pores and a higher efficiency of infection compared to TVA800. These results demonstrate that surface receptor density and the intracellular trafficking pathway used are important determinants of efficient EnvA-mediated membrane fusion, and suggest that early fusion intermediates play a critical role in establishing low pH-dependent virus entry from within acidic endosomes

    Determining Expert Opinions of the Faculty of Education on the Development of Distance Learning Course

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    A modern education system where students and faculty members are not obliged to come to the campus, where live, video, audio and interactive courses are taught in a fully virtual environment with face-to-face university education is called distance education. Based on the technological developments, the importance of distance education has also been revealed. The aim of this study is to determine the opinions of experts on the development of the ‘distance education’ course brought to the teacher training programmes. The participants of the study were selected from the purposeful sampling types with maximum diversity, criteria and easily accessible sampling methods. The data obtained as a result of interviews with experts from Northern Cyprus and Russian Universities were subjected to content analysis with a qualitative approach. In this study, which was designed as a case study, 20 academicians from 3 different departments working in the education faculty were included. In the study, a semi-structured interview form developed by the researchers was used as the data collection tool. Interviews were recorded with their consent. The data obtained as a result of interviews with experts were subjected to content analysis with a qualitative approach. As a result of the research, the experts reported teacher competencies, course application and system-oriented views for the development of the distance learning course

    Flux Single Crystal Growth of BaFe12−xTixO19 with Titanium Gradient

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    Titanium substituted barium hexaferrite BaFe12&minus;xTixO19 single crystal was grown by the top seeded solution growth method from flux on the seed with controlled cooling below 1175 &deg;C. Titanium substitution level gradient in the single crystal in the vertical and horizontal directions was studied. Two planes were cut and polished. A justification for the linear gradient of Ti substitution in a BaFe12&minus;xTixO19 single crystal is proposed; substitution levels in the center and periphery were determined. It was shown that upon growth by the top seeded solution growth method, crystals with a linear Ti substitution level gradient from x = 0.73 to x = 0.77 for a distance of 11 mm along pulling direction were obtained. The study led to the conclusion about the relationship of the gradient and changes in the composition of the nutrient solution

    Inhibitory and Toxic Effects of Volatiles Emitted by Strains of Pseudomonas and Serratia on Growth and Survival of Selected Microorganisms, Caenorhabditis elegans, and Drosophila melanogaster

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    In previous research, volatile organic compounds (VOCs) emitted by various bacteria into the chemosphere were suggested to play a significant role in the antagonistic interactions between microorganisms occupying the same ecological niche and between bacteria and target eukaryotes. Moreover, a number of volatiles released by bacteria were reported to suppress quorum-sensing cell-to-cell communication in bacteria, and to stimulate plant growth. Here, volatiles produced by Pseudomonas and Serratia strains isolated mainly from the soil or rhizosphere exhibited bacteriostatic action on phytopathogenic Agrobacterium tumefaciens and fungi and demonstrated a killing effect on cyanobacteria, flies (Drosophila melanogaster), and nematodes (Caenorhabditis elegans). VOCs emitted by the rhizospheric Pseudomonas chlororaphis strain 449 and by Serratia proteamaculans strain 94 isolated from spoiled meat were identified using gas chromatography-mass spectrometry analysis, and the effects of the main headspace compounds—ketones (2-nonanone, 2-heptanone, 2-undecanone) and dimethyl disulfide—were inhibitory toward the tested microorganisms, nematodes, and flies. The data confirmed the role of bacterial volatiles as important compounds involved in interactions between organisms under natural ecological conditions

    Evolution and current development trends of the Russian Federation’s higher education system

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    The aim of the study is to substantiate evolutionary development stages and current trends in the higher education system in the Russian Federation via general scientific methods of cognition, quantitative and qualitative assessment, methods of comparative and factor analysis, analysis and synthesis, grouping and comparison, the method of logical generalization. As a result, increasing globalization changes the approach to education. The authors came to the conclusion that it is necessary to take into account the impact of external and inter systemic factors on the development of higher education organizations in the Russian Federation.El objetivo del estudio es sustanciar las etapas de desarrollo evolutivo y las tendencias actuales en el sistema de educación superior en la Federación de Rusia a través de métodos científicos generales de cognición, evaluación cuantitativa y cualitativa, métodos de análisis comparativo y factorial, análisis y síntesis, agrupación y comparación, El método de generalización lógica. Como resultado, la creciente globalización cambia el enfoque de la educación. Los autores llegaron a la conclusión de que es necesario tener en cuenta el impacto de los factores externos e intersistémicos en el desarrollo de las organizaciones de educación superior en la Federación de Rusia
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