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1.
Strategies for signal amplification in nucleic acid detection 总被引:3,自引:0,他引:3
S. Calin Andras J. Brian Power Edward C. Cocking Michael R. Davey 《Molecular biotechnology》2001,19(1):29-44
Many aspects of molecular genetics necessitate the detection of nucleic acid sequences. Current approaches involving target
amplification (in situ PCR, Primed in situ Labeling, Self-Sustained Sequence Replication, Strand Displacement Amplification), probe amplification (Ligase Chain Reaction,
Padlock Probes, Rolling Circle Amplification) and signal amplification (Tyramide Signal Amplification, Branched DNA Amplification)
are summarized in the present review, together with their advantages and limitations. 相似文献
2.
Constitutive and IL 1-regulated murine complement gene expression is strain and tissue specific 总被引:5,自引:0,他引:5
A Falus H U Beuscher H S Auerbach H R Colten 《Journal of immunology (Baltimore, Md. : 1950)》1987,138(3):856-860
To study the molecular mechanisms accounting for strain- and tissue-specific variations in the production of complement proteins, complementary DNA probes were used to assess qualitative and quantitative differences in specific mRNA content of complement proteins C2, factor B, and C3 in extracts of tissues (liver, lung, spleen, kidney, and peritoneal macrophages) isolated from various mouse strains. Northern blot analysis of total hepatic RNA revealed differences in C2, factor B, and C3 mRNA levels in strains that share B10 background but differ in the H-2 region (e.g., H-2k, H-2u, H-2d, H-2f). In each instance, hepatic mRNA specific for the individual gene product corresponded in amount to the serum levels. By contrast, specific mRNA content of C2 and factor B in macrophages differed significantly from those observed in liver for each strain. Modulation of C2, factor B, and C3 expression was studied after in vivo administration of recombinant IL 1 or endotoxin to H-2k (B10.AKM) or H-2u (B10.PL) strain mice. As assessed by Northern blot analysis, neither endotoxin nor IL 1 affected liver C2-specific mRNA but increased specific C2 mRNA levels in kidney and lung. For both strains, IL 1 increased specific factor B mRNA in all tissues examined except for the H-2u strain liver factor B mRNA content, which was not affected by IL 1, whereas that of H-2k mice was increased. The lack of factor B modulation by IL 1 in the H-2u lines was specific to that gene and not a reflection of a generalized IL 1 unresponsiveness. Differences in tissue and strain specific constitutive and IL 1-regulated expression of the C3 gene were also observed in the H-2u and H-2k strains. 相似文献
3.
Andras Schaefer Reinhard Zibirre Peter Kabus Jutta Kühne Gebhard Koch 《Bioscience reports》1982,2(8):613-615
After exposure of HeLa cells to poliovirus there is a rapid decline (within minutes) in fluorescence polarization of DPH (1,6-diphenyl-1,3,5-hexatriene). Within one hour after infection the (Na+/K+)ATPase activity of an isolated plasma-membrane-rich fraction is enhanced, the cell volume decreases, and the intracellular concentration of a potent low-molecular-weight inhibitor of host protein synthesis increases. 相似文献
4.
Effect of amino acids on cryopreservation of cynomolgus monkey (Macaca fascicularis) sperm 总被引:3,自引:0,他引:3
The effects of three amino acids (proline, glutamine, and glycine) added to the freezing medium Tes-Tris-egg yolk (TTE) for cryopreservation of cynomolgus monkey (Macaca fascicularis) spermatozoa were studied. This is the first report on the effects of amino acids on nonhuman primate sperm cryopreservation. The addition of 5mM proline, 10mM glutamine, and 10 or 20mM glycine each significantly improved post-thaw sperm motility and membrane and acrosome integrity compared with the control (TTE alone). However, a significant decrease in motility and membrane/acrosome integrity was observed when amino acid concentrations increased to 60mM for proline and glutamine, and 80 mM for glycine. The results suggest that adding a limited amount of amino acids to the freezing media is beneficial for freezing cynomolgus monkey sperm. 相似文献
5.
Phosphoinositides account for only a tiny fraction of cellular phospholipids but are extremely important in the regulation of the recruitment and activity of many signaling proteins in cellular membranes. Phosphatidylinositol (PtdIns) 4-kinases generate PtdIns 4-phosphate, the precursor of important regulatory phosphoinositides but also an emerging regulatory molecule in its own right. The four mammalian PtdIns 4-kinases regulate a diverse array of signaling events, as well as vesicular trafficking and lipid transport, but the mechanisms by which their lipid product PtdIns 4-phosphate controls these processes is only beginning to unfold. 相似文献
6.
Transgenic mice carrying the 3-hydroxy-3-methylglutarylCoA reductase (HMG) promoter driving theEscherichia coli -galactosidase (lacZ) gene did not display the expected ubiquitous and constitutive expression inHMG-lacZ transgenic mice. The same promoter is however able to drive ubiquitous expression of the chloramphenicol acetyltransferase (cat) gene. Two lines of doubleHMG-lacZ andHMG-cat transgenic mice were obtained in which the two constructs were integrated at the same genomic sites. These mice expressed both reporter genes, but exclusively in the testes. These results suggest that thelacZ sequence might interfere negatively with the expression of the adjacentHMG-cat transgene. 相似文献
7.
Peter Andras 《PloS one》2012,7(11)
Particle swarm optimization is a popular method for solving difficult optimization problems. There have been attempts to formulate the method in formal probabilistic or stochastic terms (e.g. bare bones particle swarm) with the aim to achieve more generality and explain the practical behavior of the method. Here we present a Bayesian interpretation of the particle swarm optimization. This interpretation provides a formal framework for incorporation of prior knowledge about the problem that is being solved. Furthermore, it also allows to extend the particle optimization method through the use of kernel functions that represent the intermediary transformation of the data into a different space where the optimization problem is expected to be easier to be resolved–such transformation can be seen as a form of prior knowledge about the nature of the optimization problem. We derive from the general Bayesian formulation the commonly used particle swarm methods as particular cases. 相似文献
8.
Studies of crayfish chemical ecology have been conducted in both day and night conditions. This variation may hinder the comparison of data among studies, if the responses by crayfish to chemical cues are dependent upon the time at which the cues are encountered. We tested the hypothesis that responses to chemical cues are dependent on observation time using the red swamp crayfish, Procambarus clarkii. Procambarus clarkii is known to exhibit a light-regulated circadian rhythm, with nocturnal activity peaks. Habitat use differed significantly between non-stimulated periods and periods of exposure to a food stimulus, but no effects of photoperiod (normal vs. reversed) or laboratory conditions (dark vs. light) were observed. The results suggest that, all else being equal, (1) studies of crayfish chemical ecology can be successfully conducted in a variety of experimental conditions, and (2) previous studies conducted at various times of the day should have comparable results. 相似文献
9.
James E. Polston Carolyn E. Pritchett Jonathan M. Tomasko Ann M. Rogers Lorenzo Leggio Panayotis K. Thanos Nora D. Volkow Andras Hajnal 《PloS one》2013,8(12)
Roux-en-Y gastric bypass surgery (RYGB) is an effective treatment for severe obesity. Clinical studies however have reported susceptibility to increased alcohol use after RYGB, and preclinical studies have shown increased alcohol intake in obese rats after RYGB. This could reflect a direct enhancement of alcohol’s rewarding effects in the brain or an indirect effect due to increased alcohol absorption after RGYB. To rule out the contribution that changes in alcohol absorption have on its rewarding effects, here we assessed the effects of RYGB on intravenously (IV) administered ethanol (1%). For this purpose, high fat (60% kcal from fat) diet-induced obese male Sprague Dawley rats were tested ∼2 months after RYGB or sham surgery (SHAM) using both fixed and progressive ratio schedules of reinforcement to evaluate if RGYB modified the reinforcing effects of IV ethanol. Compared to SHAM, RYGB rats made significantly more active spout responses to earn IV ethanol during the fixed ratio schedule, and achieved higher breakpoints during the progressive ratio schedule. Although additional studies are needed, our results provide preliminary evidence that RYGB increases the rewarding effects of alcohol independent of its effects on alcohol absorption. 相似文献
10.
Hoon-Ki Sung Kyung-Oh Doh Joe Eun Son Jin Gyoon Park Yunui Bae Soojeong Choi Seana Mary Lunney Nelson Rebecca Cowling Kristina Nagy Iacovos P. Michael Gou Young Koh S. Lee Adamson Tony Pawson Andras Nagy 《Cell metabolism》2013,17(1):61-72
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