48 research outputs found

    Transcriptome profile of yeast reveals the essential role of PMA2 and uncharacterized gene YBR056W-A (MNC1) in adaptation to toxic manganese concentration

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    © The Royal Society of Chemistry.Adaptation of S. cerevisiae to toxic concentrations of manganese provides a physiological model of heavy metal homeostasis. Transcriptome analysis of adapted yeast cells reveals upregulation of cell wall and plasma membrane proteins including membrane transporters. The gene expression in adapted cells differs from that of cells under short-term toxic metal stress. Among the most significantly upregulated genes are PMA2, encoding an ortholog of Pma1 H+-ATPase of the plasma membrane, and YBR056W-A, encoding a putative membrane protein Mnc1 that belongs to the CYSTM family and presumably chelates manganese at the cell surface. We demonstrate that these genes are essential for the adaptation to toxic manganese concentration and propose an extended scheme of manganese detoxification in yeast

    Previous reproductive history and post-natal family planning among HIV-infected women in Ukraine

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    BACKGROUND: Ukraine has the highest antenatal HIV prevalence in Europe. The national prevention of mother-to-child transmission (MTCT) programme has reduced the MTCT rate, but less attention has been given to the prevention of unintended pregnancy among HIV-positive women. Our objectives were to describe the reproductive health, condom use and family planning (FP) practices of HIV-positive childbearing Ukrainian women and to identify factors associated with different methods of post-natal contraception. METHODS: HIV-infected childbearing women, diagnosed before or during pregnancy, were enrolled prospectively in a post-natal cohort study in four regional HIV/AIDS centres in Ukraine from December 2007. Logistic regression models were used to identify factors associated with post-natal FP practices. RESULTS: Data were available for 371 women enrolled by March 2009; 82% (n = 303) were married or cohabiting, 27% (97 of 363) reported a current HIV-negative sexual partner and 69% were diagnosed with HIV during their most recent pregnancy. Overall, 21% (75 of 349) of women were not using contraception post-natally (of whom 80% reported no current sexual activity), 50% (174 of 349) used condoms, 20% (74 of 349) relied solely/partially on coitus interruptus and 4% used hormonal methods or intrauterine device. Among married/cohabiting women, consistent use of condoms in the previous pregnancy [AOR 1.96 (95%CI 1.06–3.62)], having an HIV-positive partner [AOR 0.42 (0.20–0.87)], current sexual activity [AOR 4.53 (1.19–17.3)] and study site were significantly associated with post-natal condom use; 16% of those with HIV-negative partners did not use condoms. Risk factors for non-use of FP were lack of affordability [AOR 6.34 (1.73–23.2)] and inconsistent use of condoms in the previous pregnancy [AOR 7.25 (1.41–37.2)]. CONCLUSIONS: More than 40% of HIV-positive women in this population are at risk of unintended pregnancy and the one in six women in HIV-discordant couples not using barrier methods risk transmitting HIV to their partners. Our study results are limited by the observational nature of the data and the potential for both measured and unmeasured confounding

    ФОРМИРОВАНИЕ ЗАРЯДОВЫХ НАСОСОВ В СТРУКТУРЕ ФОТОПРЕОБРАЗОВАТЕЛЕЙ

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    Results of further investigation into original concept of charge pumps in the structure of photoelectric cells show that charge pumps are formed due to the formation of spatial defect−dopant complexes which produce a qualitative change in the transport mechanism of light generated charges at the base of the solar cell. For the first time a large scale charge pump manufacturing process has been offered. This process involves a non−thermal or «cold» photon annealing and uses standard photon annealing equipment. The photon annealing effect is achieved by using an original photomask (removable). The mask provides an annealing pattern with multiple light sources and heat insulation of the target wafer. This process is called local photon annealing (LPA). Due to its efficiency and simplicity the process does not require significant industrial investment. Experimental results show that it is possible to increase short circuit current and maximum power output of a solar cell with the use of the LPA technique. Experimental solar cell samples have been chosen from different manufacturers. Рассмотрены результаты дальнейшего развития оригинальной концепции зарядовой подкачки в структуре фотоэлектических преобразователей. Зарядовые насосы обусловлены образованием пространственных дефектно−примесных комплексов. Формирование зарядовых насосов в структуре приводит к изменению механизма пролета фотогенерированными носителями базы солнечного элемента. Впервые предложен технологический процесс атермального, или «холодного» фотонного отжига. Этот процесс предполагает использование стандартного оборудования для фотонного отжига. Эффект атермального фотонного отжига достигается применением оригинальной фотомаски (съемного фотошаблона). Фотошаблон обеспечивает режим отжига множественными световыми источниками и тепловую изоляцию отжигаемой пластины. Процесс получил название локального фотонного отжига. Эффективность и простота процесса не требуют значительных затрат на внедрение в производстве. Представлены результаты экспериментальных исследований по повышению тока короткого замыкания и максимальной мощности солнечных элементов за счет применения локального фотонного отжига. Эксперименты выполнены на солнечных элементах, изготовленных различными производителями

    A Review of Phosphate Mineral Nucleation in Biology and Geobiology

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    Transcriptome profile of yeast reveals the essential role of PMA2 and uncharacterized gene YBR056W-A (MNC1) in adaptation to toxic manganese concentration

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    © The Royal Society of Chemistry.Adaptation of S. cerevisiae to toxic concentrations of manganese provides a physiological model of heavy metal homeostasis. Transcriptome analysis of adapted yeast cells reveals upregulation of cell wall and plasma membrane proteins including membrane transporters. The gene expression in adapted cells differs from that of cells under short-term toxic metal stress. Among the most significantly upregulated genes are PMA2, encoding an ortholog of Pma1 H+-ATPase of the plasma membrane, and YBR056W-A, encoding a putative membrane protein Mnc1 that belongs to the CYSTM family and presumably chelates manganese at the cell surface. We demonstrate that these genes are essential for the adaptation to toxic manganese concentration and propose an extended scheme of manganese detoxification in yeast

    Transcriptome profile of yeast reveals the essential role of PMA2 and uncharacterized gene YBR056W-A (MNC1) in adaptation to toxic manganese concentration

    Get PDF
    © The Royal Society of Chemistry.Adaptation of S. cerevisiae to toxic concentrations of manganese provides a physiological model of heavy metal homeostasis. Transcriptome analysis of adapted yeast cells reveals upregulation of cell wall and plasma membrane proteins including membrane transporters. The gene expression in adapted cells differs from that of cells under short-term toxic metal stress. Among the most significantly upregulated genes are PMA2, encoding an ortholog of Pma1 H+-ATPase of the plasma membrane, and YBR056W-A, encoding a putative membrane protein Mnc1 that belongs to the CYSTM family and presumably chelates manganese at the cell surface. We demonstrate that these genes are essential for the adaptation to toxic manganese concentration and propose an extended scheme of manganese detoxification in yeast

    Transcriptome profile of yeast reveals the essential role of PMA2 and uncharacterized gene YBR056W-A (MNC1) in adaptation to toxic manganese concentration

    No full text
    © The Royal Society of Chemistry.Adaptation of S. cerevisiae to toxic concentrations of manganese provides a physiological model of heavy metal homeostasis. Transcriptome analysis of adapted yeast cells reveals upregulation of cell wall and plasma membrane proteins including membrane transporters. The gene expression in adapted cells differs from that of cells under short-term toxic metal stress. Among the most significantly upregulated genes are PMA2, encoding an ortholog of Pma1 H+-ATPase of the plasma membrane, and YBR056W-A, encoding a putative membrane protein Mnc1 that belongs to the CYSTM family and presumably chelates manganese at the cell surface. We demonstrate that these genes are essential for the adaptation to toxic manganese concentration and propose an extended scheme of manganese detoxification in yeast

    Importance of Non-Covalent Interactions in Yeast Cell Wall Molecular Organization

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    This review covers a group of non-covalently associated molecules, particularly proteins (NCAp), incorporated in the yeast cell wall (CW) with neither disulfide bridges with proteins covalently attached to polysaccharides nor other covalent bonds. Most NCAp, particularly Bgl2, are polysaccharide-remodeling enzymes. Either directly contacting their substrate or appearing as CW lipid-associated molecules, such as in vesicles, they represent the most movable enzymes and may play a central role in CW biogenesis. The absence of the covalent anchoring of NCAp allows them to be there where and when it is necessary. Another group of non-covalently attached to CW molecules are polyphosphates (polyP), the universal regulators of the activity of many enzymes. These anionic polymers are able to form complexes with metal ions and increase the diversity of non-covalent interactions through charged functional groups with both proteins and polysaccharides. The mechanism of regulation of polysaccharide-remodeling enzyme activity in the CW is unknown. We hypothesize that polyP content in the CW is regulated by another NCAp of the CW—acid phosphatase—which, along with post-translational modifications, may thus affect the activity, conformation and compartmentalization of Bgl2 and, possibly, some other polysaccharide-remodeling enzymes
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