34 research outputs found

    Π˜Π·ΡƒΡ‡Π΅Π½ΠΈΠ΅ элСктрокинСтичСских возмоТностСй сСпарации ΠΈ концСнтрирования Π±Π°ΠΊΡ‚Π΅Ρ€ΠΈΠΉ (S.aureus) Π² Ρ†Π΅Π»ΡŒΠ½ΠΎΠΉ ΠΊΡ€ΠΎΠ²ΠΈ чСтырСхэлСктродным биосСнсорным Ρ‡ΠΈΠΏ-Ρ„ΠΎΡ€ΠΌΠ°Ρ‚ΠΎΠΌ с ΠΏΡ€ΠΎΠ·Ρ€Π°Ρ‡Π½Ρ‹ΠΌΠΈ микроэлСктродами

    Get PDF
    The electrokinetic possibilities of separation and concentration of S.aureus bacteria in human whole blood (test mixture) were studied using a new design of a four-electrode biosensor chip format with transparent microelectrodes. In the measurements, a closed cell was used, into which the test mixture was poured. The electrokinetic movement of bacteria during concentration was observed when AC voltage was applied to the first and second annular external electrodes, and DC voltage was applied to the third and fourth semicircular central electrodes. The process of separation of erythrocytes and concentration of bacteria was recorded by an optical method. It is shown that the concentration of bacteria appears after 8 minutes and increases by 30 minutes in the region of the central electrodes under model conditions. The measurements were carried out on two biosensor chip formats having almost identical electrophysical parameters of capacitance and conductivity at frequencies from 100 Hz to 1 MHz. It is determined that the amplitude-frequency mode and biosensor chip format can be used to develop methodological support for the identification of bacterial species, but only by optical methods. It is shown that in order to increase the number of bacteria on both of the central electrode in the concentration mode, it is necessary to increase the speed of the electroosmotic flow at alternating current, by optimizing the composition of the medium and the parameters of the electrical regime in order to equalize the rates of separation and concentration processes.Π˜Π·ΡƒΡ‡Π΅Π½Ρ‹ элСктрокинСтичСскиС возмоТности сСпарации ΠΈ концСнтрирования Π±Π°ΠΊΡ‚Π΅Ρ€ΠΈΠΉ S.aureus Π² Ρ†Π΅Π»ΡŒΠ½ΠΎΠΉ ΠΊΡ€ΠΎΠ²ΠΈ Ρ‡Π΅Π»ΠΎΠ²Π΅ΠΊΠ° (исслСдуСмая смСсь) с ΠΏΠΎΠΌΠΎΡ‰ΡŒΡŽ Π½ΠΎΠ²ΠΎΠΉ конструкции чСтырСхэлСктродного биосСнсорного Ρ‡ΠΈΠΏ-Ρ„ΠΎΡ€ΠΌΠ°Ρ‚Π° с ΠΏΡ€ΠΎΠ·Ρ€Π°Ρ‡Π½Ρ‹ΠΌΠΈ микроэлСктродами. Π’ исслСдованиях использована закрытая ячСйка, Π² ΠΊΠΎΡ‚ΠΎΡ€ΡƒΡŽ Π·Π°Π»ΠΈΠ²Π°Π»ΠΈ ΠΈΡΡΠ»Π΅Π΄ΡƒΠ΅ΠΌΡƒΡŽ смСсь. ЭлСктрокинСтичСскоС ΠΏΠ΅Ρ€Π΅ΠΌΠ΅Ρ‰Π΅Π½ΠΈΠ΅ Π±Π°ΠΊΡ‚Π΅Ρ€ΠΈΠΉ ΠΏΡ€ΠΈ ΠΊΠΎΠ½Ρ†Π΅Π½Ρ‚Ρ€ΠΈΡ€ΠΎΠ²Π°Π½ΠΈΠΈ наблюдалось ΠΏΡ€ΠΈ ΠΏΠΎΠ΄Π°Ρ‡Π΅ Π½Π° ΠΏΠ΅Ρ€Π²Ρ‹ΠΉ ΠΈ Π²Ρ‚ΠΎΡ€ΠΎΠΉ ΠΊΠΎΠ»ΡŒΡ†Π΅Π²Ρ‹Π΅ внСшниС элСктроды ΠΏΠ΅Ρ€Π΅ΠΌΠ΅Π½Π½ΠΎΠ³ΠΎ напряТСния, Π° Π½Π° Ρ‚Ρ€Π΅Ρ‚ΠΈΠΉ ΠΈ Ρ‡Π΅Ρ‚Π²Π΅Ρ€Ρ‚Ρ‹ΠΉ ΠΏΠΎΠ»ΡƒΠΊΡ€ΡƒΠ³Π»Ρ‹Π΅ Ρ†Π΅Π½Ρ‚Ρ€Π°Π»ΡŒΠ½Ρ‹Π΅ элСктроды – постоянного напряТСния. ΠŸΡ€ΠΎΡ†Π΅ΡΡ сСпарации эритроцитов ΠΈ концСнтрирования Π±Π°ΠΊΡ‚Π΅Ρ€ΠΈΠΉ фиксировался оптичСским ΠΌΠ΅Ρ‚ΠΎΠ΄ΠΎΠΌ для ΠΌΠΎΠ΄Π΅Π»ΡŒΠ½Ρ‹Ρ… условий ΠΈ Π² Ρ†Π΅Π»ΡŒΠ½ΠΎΠΉ ΠΊΡ€ΠΎΠ²ΠΈ. Показано, Ρ‡Ρ‚ΠΎ ΠΊΠΎΠ½Ρ†Π΅Π½Ρ‚Ρ€ΠΈΡ€ΠΎΠ²Π°Π½ΠΈΠ΅ Π±Π°ΠΊΡ‚Π΅Ρ€ΠΈΠΉ проявляСтся Ρ‡Π΅Ρ€Π΅Π· 8 ΠΌΠΈΠ½ΡƒΡ‚ ΠΈ увСличиваСтся ΠΊ 30 ΠΌΠΈΠ½ΡƒΡ‚Π΅ Π² области Ρ†Π΅Π½Ρ‚Ρ€Π°Π»ΡŒΠ½Ρ‹Ρ… элСктродов Π² ΠΌΠΎΠ΄Π΅Π»ΡŒΠ½Ρ‹Ρ… условиях. Π˜Π·ΠΌΠ΅Ρ€Π΅Π½ΠΈΡ Π±Ρ‹Π»ΠΈ ΠΏΡ€ΠΎΠ²Π΅Π΄Π΅Π½Ρ‹ Π½Π° биосСнсорных Ρ‡ΠΈΠΏ-Ρ„ΠΎΡ€ΠΌΠ°Ρ‚Π°Ρ…, ΠΈΠΌΠ΅ΡŽΡ‰ΠΈΡ… практичСски ΠΎΠ΄ΠΈΠ½Π°ΠΊΠΎΠ²Ρ‹Π΅ элСктрофизичСскиС ΠΏΠ°Ρ€Π°ΠΌΠ΅Ρ‚Ρ€Ρ‹ Смкости ΠΈ проводимости Π½Π° частотах ΠΎΡ‚ 100 Π“Ρ† Π΄ΠΎ 1 ΠœΠ“Ρ†. УстановлСно, Ρ‡Ρ‚ΠΎ Π°ΠΌΠΏΠ»ΠΈΡ‚ΡƒΠ΄Π½ΠΎ-частотный Ρ€Π΅ΠΆΠΈΠΌ ΠΈ биосСнсорный Ρ‡ΠΈΠΏ-Ρ„ΠΎΡ€ΠΌΠ°Ρ‚ ΠΌΠΎΠ³ΡƒΡ‚ Π±Ρ‹Ρ‚ΡŒ ΠΈΡΠΏΠΎΠ»ΡŒΠ·ΠΎΠ²Π°Π½Ρ‹ для Ρ€Π°Π·Ρ€Π°Π±ΠΎΡ‚ΠΊΠΈ мСтодичСского обСспСчСния ΠΈΠ΄Π΅Π½Ρ‚ΠΈΡ„ΠΈΠΊΠ°Ρ†ΠΈΠΈ Π²ΠΈΠ΄Π° Π±Π°ΠΊΡ‚Π΅Ρ€ΠΈΠΉ, Π½ΠΎ Ρ‚ΠΎΠ»ΡŒΠΊΠΎ оптичСскими ΠΌΠ΅Ρ‚ΠΎΠ΄Π°ΠΌΠΈ. Показано, Ρ‡Ρ‚ΠΎ для увСличСния количСства Π±Π°ΠΊΡ‚Π΅Ρ€ΠΈΠΉ Π½Π° Ρ†Π΅Π½Ρ‚Ρ€Π°Π»ΡŒΠ½Ρ‹Ρ… элСктродах Π² Ρ€Π΅ΠΆΠΈΠΌΠ΅ концСнтрирования Π½Π΅ΠΎΠ±Ρ…ΠΎΠ΄ΠΈΠΌΠΎ ΠΏΠΎΠ²Ρ‹ΡΠΈΡ‚ΡŒ ΡΠΊΠΎΡ€ΠΎΡΡ‚ΡŒ элСктроосмотичСского ΠΏΠΎΡ‚ΠΎΠΊΠ° Π½Π° ΠΏΠ΅Ρ€Π΅ΠΌΠ΅Π½Π½ΠΎΠΌ Ρ‚ΠΎΠΊΠ΅ ΠΏΡƒΡ‚Π΅ΠΌ ΠΎΠΏΡ‚ΠΈΠΌΠΈΠ·Π°Ρ†ΠΈΠΈ состава срСды ΠΈ ΠΏΠ°Ρ€Π°ΠΌΠ΅Ρ‚Ρ€ΠΎΠ² элСктричСского Ρ€Π΅ΠΆΠΈΠΌΠ°, Ρ‡Ρ‚ΠΎΠ±Ρ‹ ΡƒΡ€Π°Π²Π½ΡΡ‚ΡŒ скорости процСссов сСпарации ΠΈ концСнтрирования

    A Genetic Signature of Spina Bifida Risk from Pathway-Informed Comprehensive Gene-Variant Analysis

    Get PDF
    Despite compelling epidemiological evidence that folic acid supplements reduce the frequency of neural tube defects (NTDs) in newborns, common variant association studies with folate metabolism genes have failed to explain the majority of NTD risk. The contribution of rare alleles as well as genetic interactions within the folate pathway have not been extensively studied in the context of NTDs. Thus, we sequenced the exons in 31 folate-related genes in a 480-member NTD case-control population to identify the full spectrum of allelic variation and determine whether rare alleles or obvious genetic interactions within this pathway affect NTD risk. We constructed a pathway model, predetermined independent of the data, which grouped genes into coherent sets reflecting the distinct metabolic compartments in the folate/one-carbon pathway (purine synthesis, pyrimidine synthesis, and homocysteine recycling to methionine). By integrating multiple variants based on these groupings, we uncovered two provocative, complex genetic risk signatures. Interestingly, these signatures differed by race/ethnicity: a Hispanic risk profile pointed to alterations in purine biosynthesis, whereas that in non-Hispanic whites implicated homocysteine metabolism. In contrast, parallel analyses that focused on individual alleles, or individual genes, as the units by which to assign risk revealed no compelling associations. These results suggest that the ability to layer pathway relationships onto clinical variant data can be uniquely informative for identifying genetic risk as well as for generating mechanistic hypotheses. Furthermore, the identification of ethnic-specific risk signatures for spina bifida resonated with epidemiological data suggesting that the underlying pathogenesis may differ between Hispanic and non-Hispanic groups
    corecore