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21.
Radchenko MV Tanaka K Waditee R Oshimi S Matsuzaki Y Fukuhara M Kobayashi H Takabe T Nakamura T 《The Journal of biological chemistry》2006,281(29):19822-19829
The intracellular level of potassium (K(+)) in Escherichia coli is regulated through multiple K(+) transport systems. Recent data indicate that not all K(+) extrusion system(s) have been identified (15). Here we report that the E. coli Na(+) (Ca(2+))/H(+) antiporter ChaA functions as a K(+) extrusion system. Cells expressing ChaA mediated K(+) efflux against a K(+) concentration gradient. E. coli strains lacking the chaA gene were unable to extrude K(+) under conditions in which wild-type cells extruded K(+). The K(+)/H(+) antiporter activity of ChaA was detected by using inverted membrane vesicles produced using a French press. Physiological growth studies indicated that E. coli uses ChaA to discard excessive K(+), which is toxic for these cells. These results suggest that ChaA K(+)/H(+) antiporter activity enables E. coli to adapt to K(+) salinity stress and to maintain K(+) homeostasis. 相似文献
22.
Omaira Vera Lizcano Sarah Stela Resende Yonne F Chehuan Marcus VG Lacerda Cristiana FA Brito Mariano G Zalis 《Memórias do Instituto Oswaldo Cruz》2014,109(7):948-951
The molecular basis of Plasmodium vivax chloroquine (CQ) resistance
is still unknown. Elucidating the molecular background of parasites that are
sensitive or resistant to CQ will help to identify and monitor the spread of
resistance. By genotyping a panel of molecular markers, we demonstrate a similar
genetic variability between in vitro CQ-resistant and sensitive phenotypes of
P. vivax parasites. However, our studies identified two
loci (MS8 and MSP1-B10) that could be used to discriminate
between both CQ-susceptible phenotypes among P. vivax isolates in
vitro. These preliminary data suggest that microsatellites may be used to identify
and to monitor the spread of P. vivax-resistance around the
world. 相似文献
23.
Vonarshenko AV Radchenko VV Gapon MV Rodionov IL Babichenko II Kakuev DL Artamonov ID Garkovenko AV D'iachkova LG Lipkin VM Kostanian IA 《Bioorganicheskaia khimiia》2007,33(6):653-656
We found a new protein haponin (an HLDF-alike protein) in promyelocyte HL-60 cells that is immunoreactive to polyclonal antibodies against HLDFbeta. Determination of the partial primary structure of the protein allowed us to reveal an immunogenic peptide of haponin and, on the basis of the amino acid sequence of this peptide, the degenerate primers were synthesized, which enabled us to clone the full-size cDNA of haponin. The stable heterologous expression of this cDNA in E. coli cells (Rosetta strain) was obtained. Preparations of natural and recombinant proteins exhibited antigenic cross-reactivity to polyclonal antibodies against this peptide. 相似文献
24.
Standard parameters of external respiration at the aerobic–anaerobic transition and above the anaerobic (ventilatory) threshold (AT) were studied in highly trained athletes during an incremental treadmill test. The efficiency of the adaptive response (AR) was inferred from changes in the heart rate and VO2gradients beyond the AT. Several AR types differing in the efficiency of the AT to the physical load were identified. The most efficient AR was associated with a decrease in the heart rate gradient and an increase in the VO2gradient above the AT. The least efficient AR was associated with an increase in the heart rate gradient and a decrease in the VO2gradient above the AT. The efficiency of the AR to cyclic muscular load varies daily in individual athletes. 相似文献
25.
E. V. Il’nitskaya O. G. Shamborant V. V. Radchenko T. M. Shuvaeva V. M. Lipkin 《Russian Journal of Bioorganic Chemistry》2006,32(3):301-302
The binding of phosphatidylinositol-3,4,5-triphosphate to a protein with molecular mass of 45 kDa from rat olfactory epithelium (p45) was investigated using a model membrane system. Liposomes containing a mixture of phospholipids (phosphatidylethanolamine, phosphatidylcholine, and phosphatidylinositol-3,4,5-triphosphate) were used in the study. The binding of the protein to liposomes caused by its interaction with phosphatidylinositol-3,4,5-triphosphate was confirmed by cosedimentation and immunoblotting with chemiluminescent detection using monoclonal antibodies to the native protein p45. 相似文献
26.
Marcos A Gimenes Andrea A Hoshino Andrea VG Barbosa Dario A Palmieri Catalina R Lopes 《BMC plant biology》2007,7(1):9
Background
The genus Arachis includes Arachis hypogaea (cultivated peanut) and wild species that are used in peanut breeding or as forage. Molecular markers have been employed in several studies of this genus, but microsatellite markers have only been used in few investigations. Microsatellites are very informative and are useful to assess genetic variability, analyze mating systems and in genetic mapping. The objectives of this study were to develop A. hypogaea microsatellite loci and to evaluate the transferability of these markers to other Arachis species. 相似文献27.
VG Minero D De Stefanis P Costelli FM Baccino G Bonelli 《Cell cycle (Georgetown, Tex.)》2015,14(7):1090-1102
High mortality among hepatocellular carcinoma (HCC) patients reflects both late diagnosis and low curability, due to pharmacoresistance. Taxol (TAX) is toxic for many human HCC-derived cell lines, yet its clinical efficacy on HCCs is poor. Combining TAX with other drugs appears a promising possibility to overcome such refractoriness. We analyzed whether combining tumor necrosis factor (TNF) with TAX would improve their toxicity. Human HCC-derived cell lines were treated with TAX or TNF, alone or combined. Apoptosis was assessed by morphology and flow-cytometry. Several pro- and anti-apoptotic molecules were evaluated by western blotting and/or enzymatic assay. After a 24 hour treatment, TNF was ineffective and TAX modestly cytotoxic, whereas HCC cells were conditionally sensitized to TNF by TAX. Indeed some relevant parameters were shifted to a prodeath setting: TNF-receptor 1 was increased, SOCS3, c-FLIP and pSTAT3 were markedly downregulated. These observations provide a significant clue to critically improve the drug susceptibility of HCC cells by combining 2 agents, TAX and TNF. The sequential application of TAX at a low dosage followed by TNF for only a short time triggered a strong apoptotic response. Of interest, prior TAX administration could also sensitize to TNF-induced apoptosis in the Yoshida AH-130 hepatoma transplanted in mice. Therefore, scrutinizing the possibility to develop similar combination drug regimens in suitable preclinical models seems highly advisable. 相似文献
28.
29.
Stephanie Zobrist Marcelo Brito Eduardo Garbin Wuelton M. Monteiro Suellen Clementino Freitas Marcela Macedo Aline Soares Moura Nicole Advani Maria Kahn Sampa Pal Emily Gerth-Guyette Pooja Bansil Gonzalo J. Domingo Dhelio Pereira Marcus VG Lacerda 《PLoS neglected tropical diseases》2021,15(8)
BackgroundGlucose-6-phosphate dehydrogenase (G6PD) deficiency is a common enzyme deficiency, prevalent in many malaria-endemic countries. G6PD-deficient individuals are susceptible to hemolysis during oxidative stress, which can occur from exposure to certain medications, including 8-aminoquinolines used to treat Plasmodium vivax malaria. Accordingly, access to point-of-care (POC) G6PD testing in Brazil is critical for safe treatment of P. vivax malaria.Methodology/Principal findingsThis study evaluated the performance of the semi-quantitative, POC STANDARD G6PD Test (SD Biosensor, Republic of Korea). Participants were recruited at clinics and through an enriched sample in Manaus and Porto Velho, Brazil. G6PD and hemoglobin measurements were obtained from capillary samples at the POC using the STANDARD and HemoCue 201+ (HemoCue AB, Sweden) tests. A thick blood slide was prepared for malaria microscopy. At the laboratories, the STANDARD and HemoCue tests were repeated on venous samples and a quantitative spectrophotometric G6PD reference assay was performed (Pointe Scientific, Canton, MI). G6PD was also assessed by fluorescent spot test. In Manaus, a complete blood count was performed.Samples were analyzed from 1,736 participants. In comparison to spectrophotometry, the STANDARD G6PD Test performed equivalently in determining G6PD status in venous and capillary specimens under varied operating temperatures. Using the manufacturer-recommended reference value thresholds, the test’s sensitivity at the <30% threshold on both specimen types was 100% (95% confidence interval [CI] venous 93.6%–100.0%; capillary 93.8%–100.0%). Specificity was 98.6% on venous specimens (95% CI 97.9%–99.1%) and 97.8% on capillary (95% CI 97.0%–98.5%). At the 70% threshold, the test’s sensitivity was 96.9% on venous specimens (95% CI 83.8%–99.9%) and 94.3% on capillary (95% CI 80.8%–99.3%). Specificity was 96.5% (95% CI 95.0%–97.6%) and 92.3% (95% CI 90.3%–94.0%) on venous and capillary specimens, respectively.Conclusion/SignificanceThe STANDARD G6PD Test is a promising tool to aid in POC detection of G6PD deficiency in Brazil.Trial registrationThis study was registered with ClinicalTrials.gov (identifier: ). NCT04033640相似文献
30.
V. I. Radchenko S. V. Loboda A. L. Figurkin K. M. Gorbatenko E. E. Ovsyannikov 《Russian Journal of Marine Biology》2010,36(7):473-488
The distribution of temperature, salinity, phytoplankton, zooplankton, and nekton, including Pink Salmon and Chum Salmon,
is analyzed based on the data from a complex survey conducted in the upper epipelagic zone of the northwestern Pacific Ocean
in June–July 2009. An estimate of water transfer, plankton biomass (by size fractions and taxonomic groups), and biomass and
abundance of nekton is made. The water circulation pattern was notable for the “compressed” state of the Western Subarctic
Gyre. Copepods predominated in zooplankton (60.8% biomass), and Pacific Salmon dominated in the nekton. The ratio of the plankton
biomass to the nekton biomass in various biostatistical areas varied from 23.9 to 195.1 (mean 46.7). It was found that the
nekton biomass in the area of the spreading subarctic waters reaches its maximum in the summer months and that in the area
of subtropical waters reaches its maximum in the fall. In the upper 30-meter layer, the biomass of fish and squid rose during
the night to 2.92 million tons, or 1.6 times as much, due to mesopelagic migrants. The nekton communities of the upper epipelagic
of the northwestern Pacific Ocean functioned normally, providing a high level of biological and fish productivity. 相似文献