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21.
Enik? Sirály ádám Szabó Bernadett Szita Vivienne Kovács Zsuzsanna Fodor Csilla Marosi Pál Salacz Zoltán Hidasi Viktor Maros Péter Hanák éva Csibri Gábor Csukly 《PloS one》2015,10(2)
BackgroundIt is anticipated that current and future preventive therapies will likely be more effective in the early stages of dementia, when everyday functioning is not affected. Accordingly the early identification of people at risk is particularly important. In most cases, when subjects visit an expert and are examined using neuropsychological tests, the disease has already been developed. Contrary to this cognitive games are played by healthy, well functioning elderly people, subjects who should be monitored for early signs. Further advantages of cognitive games are their accessibility and their cost-effectiveness.PurposeThe aim of the investigation was to show that computer games can help to identify those who are at risk. In order to validate games analysis was completed which measured the correlations between results of the ''Find the Pairs'' memory game and the volumes of the temporal brain regions previously found to be good predictors of later cognitive decline.ResultsThere was a correlation between the number of attempts and the time required to complete the memory game and the volume of the entorhinal cortex, the temporal pole, and the hippocampus. There was also a correlation between the results of the Paired Associates Learning (PAL) test and the memory game.ConclusionsThe results gathered support the initial hypothesis that healthy elderly subjects achieving lower scores in the memory game have increased level of atrophy in the temporal brain structures and showed a decreased performance in the PAL test. Based on these results it can be concluded that memory games may be useful in early screening for cognitive decline. 相似文献
22.
We report the integration of a type II restriction-methylase, mFokI, into the tobacco chloroplast genome and we demonstrate that the introduced enzyme effectively directs the methylation of its target sequence in vivo and does not affect maternal inheritance. We further report the transformation of tobacco with an E. coli dcm methylase targeted to plastids and we demonstrate efficient cytosine methylation of the plastid genome. Both adenosine methylation of FokI sites and cytosine methylation of dcm sites appeared phenotypically neutral. The ability to tolerate such plastid genome methylation is a pre-requisite for a proposed plant transgene containment system. In such a system, a chloroplast located, maternally inherited restriction methylase would provide protection from a nuclear-encoded, plastid targeted restriction endonuclease. As plastids are not paternally inherited in most crop species, pollen from such plants would carry the endonuclease transgene but not the corresponding methylase; the consequence of this should be containment of all nuclear transgenes, as pollination will only be viable in crosses to the appropriate transplastomic maternal background. 相似文献
23.
Eszter Bognar Zsolt Sarszegi Aliz Szabo Balazs Debreceni Nikoletta Kalman Zsuzsanna Tucsek Balazs Sumegi Ferenc Gallyas Jr 《PloS one》2013,8(6)
Background
Red wine polyphenols can prevent cardiovascular and inflammatory diseases. Resveratrol, the most extensively studied constituent, is unlikely to solely account for these beneficial effects because of its rather low abundance and bioavailability. Malvidin is far the most abundant polyphenol in red wine; however, very limited data are available about its effect on inflammatory processes and kinase signaling pathways.Methods & Findings
The present study was carried out by using RAW 264.7 macrophages stimulated by bacterial lipopolysaccharide in the presence and absence of malvidin. From the cells, activation of nuclear factor-kappaB, mitogen-activated protein kinase, protein kinase B/Akt and poly ADP-ribose polymerase, reactive oxygen species production, mitogen-activated protein kinase phosphatase-1 expression and mitochondrial depolarization were determined. We found that malvidin attenuated lipopolysaccharide-induced nuclear factor-kappaB, poly ADP-ribose polymerase and mitogen-activated protein kinase activation, reactive oxygen species production and mitochondrial depolarization, while upregulated the compensatory processes; mitogen-activated protein kinase phosphatase-1 expression and Akt activation.Conclusions
These effects of malvidin may explain the previous findings and at least partially account for the positive effects of moderate red wine consumption on inflammation-mediated chronic maladies such as obesity, diabetes, hypertension and cardiovascular disease. 相似文献24.
Zsuzsanna Sük?sd M. Shel Swenson J?rgen Kjems Christine E. Heitsch 《Nucleic acids research》2013,41(5):2807-2816
Recent advances in RNA structure determination include using data from high-throughput probing experiments to improve thermodynamic prediction accuracy. We evaluate the extent and nature of improvements in data-directed predictions for a diverse set of 16S/18S ribosomal sequences using a stochastic model of experimental SHAPE data. The average accuracy for 1000 data-directed predictions always improves over the original minimum free energy (MFE) structure. However, the amount of improvement varies with the sequence, exhibiting a correlation with MFE accuracy. Further analysis of this correlation shows that accurate MFE base pairs are typically preserved in a data-directed prediction, whereas inaccurate ones are not. Thus, the positive predictive value of common base pairs is consistently higher than the directed prediction accuracy. Finally, we confirm sequence dependencies in the directability of thermodynamic predictions and investigate the potential for greater accuracy improvements in the worst performing test sequence. 相似文献
25.
Swenson MS Anderson J Ash A Gaurav P Sukosd Z Bader DA Harvey SC Heitsch CE 《BMC research notes》2012,5(1):341
ABSTRACT: BACKGROUND: Accurate and efficient RNA secondary structure prediction remains an important open problem in computational molecular biology. Historically, advances in computing technology have enabled faster and more accurate RNA secondary structure predictions. Previous parallelized prediction programs achieved significant improvements in runtime, but their implementations were not portable from niche high-performance computers or easily accessible to most RNA researchers. With the increasing prevalence of multi-core desktop machines, a new parallel prediction program is needed to take full advantage of today's computing technology. FINDINGS: We present here the first implementation of RNA secondary structure prediction by thermodynamic optimization for modern multi-core computers. We show that GTfold predicts secondary structure in less time than UNAfold and RNAfold, without sacrificing accuracy, on machines with four or more cores. CONCLUSIONS: GTfold supports advances in RNA structural biology by reducing the timescales for secondary structure prediction. The difference will be particularly valuable to researchers working with lengthy RNA sequences, such as RNA viral genomes. 相似文献
26.
Márta Gulyás Zsuzsanna Ács György Rappay Gábor B. Makara 《Histochemistry and cell biology》1993,100(6):503-507
The aim of this work was to detect if hypothalamic-pituitary maturation was accompanied by significant proliferation changes in differentiated pituitary cell pools. For this purpose, pituitary corticotroph (Ct), mammotroph (Mt) and somatotroph (St) proliferation activities were scanned in intact female rats during the postnatal (P) period (1–35 postnatal days). The techniques of tritiated thymidine labelling, immunostaining and autoradiography were combined to visualize DNA synthesis of hormone containing cells. Immunoreactive cell densities were measured using image analysis, and double labelled cells were counted. Corticotroph proliferation activity increased significantly on day P12, followed by an increase in the Ct proportion on days P13–14. This is the first observation of a spontaneous change of corticotroph proliferation at the end of the stress nonresponsive period. The mammotroph density and proliferation rate increased gradually during postnatal maturation, until the Mt pool overran other cell types of the female hypophysis on day 35. The somatotroph pool was the most numerous until day P20; the proliferation rate remained constant while St proportions increased reaching a plateau between days P13 and 20, then decreased to the adult level. Each cell type examined showed a characteristic, individual density and proliferation pattern. 相似文献
27.
Das U Molnár J Baráth Z Bata Z Dimmock JR 《Bioorganic & medicinal chemistry letters》2008,18(12):3484-3487
The 1-[4-(2-aminoethoxy)phenylcarbonyl]-3,5-bis-(benzylidene)-4-oxopiperidines 5-8 are a novel cluster of highly potent P-glycoprotein dependent multidrug resistance (MDR) revertants. Using a concentration of 4mug/mL, these compounds possess 11-43 times the potency of verapamil in reversing MDR in murine L-5178 lymphoma cells transfected with the human MDR1 gene. Structure-activity relationships reveal that the attachment of the N-aroyl group to various 3,5-bis(benzylidene)-4-piperidones is essential for MDR reversal to occur. In terms of potencies, the 1-piperidinyl group is the preferred terminal amine while the 4-methyl and 4-chloro substituents are the optimal groups for placement in the benzylidene aryl rings. 相似文献
28.
29.
Short Inverted-Repeat Transposable Elements in Teleost Fish and Implications for a Mechanism of Their Amplification 总被引:7,自引:0,他引:7
Zsuzsanna Izsvák Zoltán Ivics Nobuyoshi Shimoda Deanna Mohn Hitoshi Okamoto Perry B. Hackett 《Journal of molecular evolution》1999,48(1):13-21
Angel is the first miniature inverted-repeat transposable element (MITE) isolated from fish. Angel elements are imperfect palindromes with the potential to form stem-loop structures in vitro. Despite sequence divergence
of elements of up to 55% within and between species, their inverted repeat structures have been maintained, implying functional
importance. We estimate that there are about 103–104
Angels scattered throughout the zebrafish genome, evidence that this family of transposable elements has been significantly amplified
over the course of evolution. Angel elements and Xenopus MITEs carry common sequence motifs at their termini, indicating common origin and/or related mechanisms of transposition.
We present a model in which MITEs take advantage of the basic cellular mechanism of DNA replication for their amplification,
which is dependent on the characteristic inverted repeat structures of these elements. We propose that MITEs are genomic parasites
that transpose via a DNA intermediate, which forms by a folding-back of a single strand of DNA, that borrow all of the necessary
factors for their amplification from products encoded in the genomes in which they reside. DNA polymorphisms in different
lines of zebrafish were detected by PCR using Angel-specific primers, indicating that such elements, combined with other transposons in vertebrate genomes, will be useful molecular
tools for genome mapping and genetic analyses of mutations.
Received: 7 April 1998 / Accepted: 7 April 1998 相似文献
30.
In autoimmune (type 1) diabetes, autoreactive lymphocytes destroy pancreatic β-cells responsible for insulin synthesis. To
assess the feasibility of gene therapy for type 1 diabetes, recombinant vaccinia virus (rVV) vectors were constructed expressing
pancreatic islet autoantigens proinsulin (INS) and a 55-kDa immunogenic peptide from glutamic acid decarboxylase (GAD), and
the immunomodulatory cytokine interleukin (IL)-10. To augment the beneficial effects of recombinant virus therapy, the INS
and GAD genes were fused to the C terminus of the cholera toxin B subunit (CTB). Five-week-old non-obese diabetic (NOD) mice
were injected once with rVV. Humoral antibody immune responses and hyperglycemia in the infected mice were analyzed.
Only 20% of the mice inoculated with rVV expressing the CTB::INS fusion protein developed hyperglycemia, in comparison to
70% of the mice in the uninoculated animal group. Islets from pancreatic tissues isolated from euglycemic mice from this animal
group showed no sign of inflammatory lymphocyte invasion. Inoculation with rVV producing CTB::GAD or IL-10 was somewhat less
effective in reducing diabetes. Humoral antibody isotypes of hyperglycemic and euglycemic mice from all treated groups possessed
similar IgG1/IgG2c antibody titer ratios from 19 to 32 wk after virus inoculation. In comparison with uninoculated mice, 11-wk-old
NOD mice injected with virus expressing CTB::INS were delayed in diabetes onset by more than 4 wk. The experimental results
demonstrate the feasibility of using rVV expressing CTB::INS fusion protein to generate significant protection and therapy
against type 1 diabetes onset and progression. 相似文献