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991.
992.
Yumie Takagi Takashi Kuramoto Birger Voigt Toshiko Tsurumi Satoshi Nakanishi Tomoji Mashimo Norio Masui Tadao Serikawa 《Immunogenetics》2009,61(3):189-197
Almost 10,000 single nucleotide polymorphisms (SNPs) had been identified in the RT1 complex, the major histocompatibility complex of the rat, but less than ∼0.5% have been characterized. In the context of
the incomplete characterization of most SNPs, simple sequence length polymorphism (SSLP) marker development is still valuable
for understanding the involvement of genes in the RT1 in controlling disease susceptibility, since SSLPs are user-friendly and cost-effective genetic markers in rat genome analysis.
In this study, we developed a set of 67 SSLP markers, including 57 novel markers, to cover the entire RT1 complex and then created genetic profiles across 67 rat strains. These markers are located almost every 50 kb in the RT1 complex and show comparable polymorphism; the average number of alleles was 8.04 ± 3.44 and the average polymorphic rate
was 71 ± 23%. Interestingly, markers failing to amplify polymerase chain reaction products were highly observed in all strains
except for BN/SsNHsd, which suggests the existence of highly variable genomic sequences or genomic rearrangements in the RT1 region across rat strains. Based on the phylogenic tree and individual genotyping data, we identified 28 SSLP marker haplotypes
in the RT1 region that roughly consisted of three genomic regions. These findings provided new insight into the genomic organization
of the RT1 complex and we recognized the need of additional RT1 genome sequences in different strains. Owing to the accuracy and ease of determination, PCR-based SSLP genotyping could replace
serological typing in genetic analyses and characterization of rat major histocompatibility.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
An erratum to this article can be found at 相似文献
993.
Photosynthesis Research - Several species of unicellular green algae, such as the model green microalga Chlamydomonas reinhardtii, can operate under either aerobic photosynthesis or anaerobic... 相似文献
994.
Fredrik Pontén Marcus Gry Linn Fagerberg Emma Lundberg Anna Asplund Lisa Berglund Per Oksvold Erik Björling Sophia Hober Caroline Kampf Sanjay Navani Peter Nilsson Jenny Ottosson Anja Persson Henrik Wernérus Kenneth Wester Mathias Uhlén 《Molecular systems biology》2009,5(1)
Defining the protein profiles of tissues and organs is critical to understanding the unique characteristics of the various cell types in the human body. In this study, we report on an anatomically comprehensive analysis of 4842 protein profiles in 48 human tissues and 45 human cell lines. A detailed analysis of over 2 million manually annotated, high‐resolution, immunohistochemistry‐based images showed a high fraction (>65%) of expressed proteins in most cells and tissues, with very few proteins (<2%) detected in any single cell type. Similarly, confocal microscopy in three human cell lines detected expression of more than 70% of the analyzed proteins. Despite this ubiquitous expression, hierarchical clustering analysis, based on global protein expression patterns, shows that the analyzed cells can be still subdivided into groups according to the current concepts of histology and cellular differentiation. This study suggests that tissue specificity is achieved by precise regulation of protein levels in space and time, and that different tissues in the body acquire their unique characteristics by controlling not which proteins are expressed but how much of each is produced. 相似文献
995.
996.
Vanesa Esteban Silvia Heringer-Walther Anja Sterner-Kock Ron de Bruin Sandra van den Engel Yong Wang Sergio Mezzano Jesus Egido Heinz-Peter Schultheiss Marta Ruiz-Ortega Thomas Walther 《PloS one》2009,4(4)
Angiotensin (Ang) II mediates pathophysiologial changes in the kidney. Ang-(1–7) by interacting with the G protein-coupled receptor Mas may also have important biological activities.In this study, renal deficiency for Mas diminished renal damage in models of renal insufficiency as unilateral ureteral obstruction and ischemia/reperfusion injury while the infusion of Ang-(1–7) to wild-type mice pronounced the pathological outcome by aggravating the inflammatory response. Mas deficiency inhibited NF-κB activation and thus the elevation of inflammation-stimulating cytokines, while Ang-(1–7) infusion had proinflammatory properties in experimental models of renal failure as well as under basal conditions. The Ang-(1–7)-mediated NF-κB activation was Mas dependent but did not involve Ang II receptors. Therefore, the blockade of the NF-κB-activating properties of the receptor Mas could be a new strategy in the therapy of failing kidney. 相似文献
997.
Joachim Lange Marc de Lussanet Simone Kuhlmann Anja Zimmermann Markus Lappe Pienie Zwitserlood Christian Dobel 《PloS one》2009,4(10)
Prosopagnosia is a deficit in recognizing people from their faces. Acquired prosopagnosia results after brain damage, developmental or congenital prosopagnosia (CP) is not caused by brain lesion, but has presumably been present from early childhood onwards. Since other sensory, perceptual, and cognitive abilities are largely spared, CP is considered to be a stimulus-specific deficit, limited to face processing. Given that recent behavioral and imaging studies indicate a close relationship of face and biological-motion perception in healthy adults, we hypothesized that biological motion processing should be impaired in CP. Five individuals with CP and ten matched healthy controls were tested with diverse biological-motion stimuli and tasks. Four of the CP individuals showed severe deficits in biological-motion processing, while one performed within the lower range of the controls. A discriminant analysis classified all participants correctly with a very high probability for each participant. These findings demonstrate that in CP, impaired perception of faces can be accompanied by impaired biological-motion perception. We discuss implications for dedicated and shared mechanisms involved in the perception of faces and biological motion. 相似文献
998.
Solvig Diederichs Stefanie Röker Dana Marten Anja Peterbauer Thomas Scheper Martijn van Griensven Cornelia Kasper 《Biotechnology progress》2009,25(6):1762-1771
Because the regeneration of large bone defects is limited by quantitative restrictions and risks of infections, the development of bioartificial bone substitutes is of great importance. To obtain a three‐dimensional functional tissue‐like graft, static cultivation is inexpedient due to limitations in cell density, nutrition and oxygen support. Dynamic cultivation in a bioreactor system can overcome these restrictions and furthermore provide the possibility to control the environment with regard to pH, oxygen content, and temperature. In this study, a three‐dimensional bone construct was engineered by the use of dynamic bioreactor technology. Human adipose tissue derived mesenchymal stem cells were cultivated on a macroporous zirconium dioxide based ceramic disc called Sponceram®. Furthermore, hydroxyapatite coated Sponceram® was used. The cells were cultivated under dynamic conditions and compared with statically cultivated cells. The differentiation into osteoblasts was initiated by osteogenic supplements. Cellular proliferation during static and dynamic cultivation was compared measuring glucose and lactate concentration. The differentiation process was analysed determining AP‐expression and using different specific staining methods. Our results demonstrate much higher proliferation rates during dynamic conditions in the bioreactor system compared to static cultivation measured by glucose consumption and lactate production. Cell densities on the scaffolds indicated higher proliferation on native Sponceram® compared to hydroxyapatite coated Sponceram®. With this study, we present an excellent method to enhance cellular proliferation and bone lineage specific growth of tissue like structures comprising fibrous (collagen) and globular (mineral) extracellular components. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 相似文献
999.
In the present study, we show that the extracellular addition of nicotinamide adenine dinucleotide (NAD+) induces a transient rise in [Ca2+]i in human monocytes caused by an influx of extracellular calcium. The NAD+-induced Ca2+ response was prevented by adenosine triphosphate (ATP), suggesting the involvement of ATP receptors. Of the two subtypes
of ATP receptors (P2X and P2Y), the P2X receptors were considered the most likely candidates. By the use of subtype preferential
agonists and antagonists, we identified P2X1, P2X4, and P2X7 receptors being engaged in the NAD+-induced rise in [Ca2+]i. Among the P2X receptor subtypes, the P2X7 receptor is unique in facilitating the induction of nonselective pores that allow entry of ethidium upon stimulation with
ATP. In monocytes, opening of P2X7 receptor-dependent pores strongly depends on specific ionic conditions. Measuring pore formation in response to NAD+, we found that NAD+ unlike ATP lacks the ability to induce this pore-forming response. Whereas as little as 100 μM ATP was sufficient to activate
the nonselective pore, NAD+ at concentrations up to 2 mM had no effect. Taken together, these data indicate that despite similarities in the action of
extracellular NAD+ and ATP there are nucleotide-specific variations. So far, common and distinct features of the two nucleotides are only beginning
to be understood. 相似文献
1000.
Sigve?Nakken Ophélie?Aussedat Anja?Br?then?Kristoffersen Arne?Holst-Jensen Torstein?TengsEmail author 《Annals of microbiology》2009,59(2):391
We have developed a web-based tool for design of specific PCR primers and probes. The program allows you to enter primer sequence information as well as an optional probe, and sequence similarity searches (MegaBLAST) will be performed to see if the sequences match the same sequence entry in the specified database. If primers (and probe) match, this will be reported. The program can handle overlapping amplicons, amplification from a single primer, ambiguous bases and other problematic cases. 相似文献