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Gabriel Rinnerthaler Hubert Hackl Simon Peter Gampenrieder Frank Hamacher Clemens Hufnagl Cornelia Hauser-Kronberger Franz Zehentmayr Gerd Fastner Felix Sedlmayer Brigitte Mlineritsch Richard Greil 《International journal of molecular sciences》2016,17(2)
For quantitative microRNA analyses in formalin-fixed paraffin-embedded (FFPE) tissue, expression levels have to be normalized to endogenous controls. To investigate the most stably-expressed microRNAs in breast cancer and its surrounding tissue, we used tumor samples from primary tumors and from metastatic sites. MiRNA profiling using TaqMan® Array Human MicroRNA Cards, enabling quantification of 754 unique human miRNAs, was performed in FFPE specimens from 58 patients with metastatic breast cancer. Forty-two (72%) samples were collected from primary tumors and 16 (28%) from metastases. In a cross-platform analysis of a validation cohort of 32 FFPE samples from patients with early breast cancer genome-wide microRNA expression analysis using SurePrintG3 miRNA (8 × 60 K)® microarrays from Agilent® was performed. Eleven microRNAs could be detected in all samples analyzed. Based on NormFinder and geNorm stability values and the high correlation (rho ≥ 0.8) with the median of all measured microRNAs, miR-16-5p, miR-29a-3p, miR-126-3p, and miR-222-3p are suitable single gene housekeeper candidates. In the cross-platform validation, 29 human microRNAs were strongly expressed (mean log2-intensity > 10) and 21 of these microRNAs including miR-16-5p and miR-29a-3p were also stably expressed (CV < 5%). Thus, miR-16-5p and miR-29a-3p are both strong housekeeper candidates. Their Normfinder stability values calculated across the primary tumor and metastases subgroup indicate that miR-29a-3p can be considered as the strongest housekeeper in a cohort with mainly samples from primary tumors, whereas miR-16-5p might perform better in a metastatic sample enriched cohort. 相似文献
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Venkatesh Ramakrishnan Tobias Veerkamp Gerd Ascheid Marc Adrat Markus Antweiler 《Journal of Signal Processing Systems》2012,69(1):41-53
Matrix decomposition of the channel matrix in the form of QR decomposition (QRD) is needed for advanced multiple input and multiple output (MIMO) demapping algorithms like sphere decoder. Due to the computation-intensive nature of the QRD, its implementation has to be highly efficient. Flexibility in several forms, e.g. support for different algorithms, reusability of wireless implementations, portability, etc. is highly sought in wireless devices. The contradictory nature of flexibility and efficiency requires tradeoffs to be made between them in system development. In this paper, we have analyzed such tradeoffs by implementing two minimum mean squared error-sorted QRD algorithms. The algorithms have been implemented in four different methods with varying degree of reusability and in five different forms of portability. The performance of the implementations is evaluated by using the real-time constraints from the LTE standard. For all the implementations, modular equations for accurately estimating the execution time are derived. 相似文献
86.
Monitoring kidney and renal cyst volumes applying MR approaches on a rapamycin treated mouse model of ADPKD 总被引:1,自引:1,他引:0
Wilfried Reichardt Daniel Romaker Anne Becker Martin Buechert Gerd Walz Dominik von Elverfeldt 《Magma (New York, N.Y.)》2009,22(3):143-149
Object The aim of our study was to determine total cystic volume in a mouse model of PKD using MR imaging to monitor therapeutic
effects in vivo.
Materials and methods We imaged eight female pcy-mice in two groups: four belonged to an untreated control group and four were treated with the anticystic agent rapamycin,
which has proven to be effective in reducing cystogenesis in animal models. The mice were imaged using a 9.4 Tesla animal
scanner. MRI measurements were taken at six time points during the therapy. Total renal volumes and total cyst volumes were
calculated using a thresholding approach.
Results During the course of the treatment, the total cyst volume increased significantly faster than the total renal volume in the
untreated group, indicating that growth of the total renal volume in the untreated group was primarily due to the growth of
the cysts, rather than the parenchyma. The measured total renal volume in the control (placebo) group was significantly higher
than the volume in the treated group.
Conclusion Using MRI, we were able to monitor the cystic volume in a mouse model of PKD to assess the therapeutic effect of anticystic
treatment. 相似文献
87.
An experimental investigation on the influence of phenol on the solubility of CO2 in aqueous solutions of NaOH 下载免费PDF全文
Michael Jödecke Jianzhong Xia Álvaro Pérez‐Salado Kamps Gerd Maurer 《American Institute of Chemical Engineers》2015,61(9):2832-2840
Experimental results are presented for the solubility of CO2 in an aqueous solution of phenol and NaOH (molalties in water: phenol: 0.5; NaOH: 1.0) at (314, 354, and 395) K and pressures up to 10 MPa. The experimental work extends recent investigations on the influence of phenol as well as of (phenol + NaCl) on the solubility of CO2 in water. In contrast to those previous investigations, the strong electrolyte reacts with carbon dioxide and also with phenol. The experimental results are compared with predictions from a thermodynamic model. That model combines a model for the “chemical” solubility of CO2 in aqueous solutions of NaOH with a model for the “physical” solubility of CO2 in aqueous solutions of phenol. An extension is introduced to account for the chemical reaction between the weak acid phenol and the strong base sodium hydroxide. The prediction results nicely agree with the new experimental data. © 2015 American Institute of Chemical Engineers AIChE J, 61: 2832–2840, 2015 相似文献
88.
Template‐Directed Directionally Solidified 3D Mesostructured AgCl–KCl Eutectic Photonic Crystals 下载免费PDF全文
89.
Photonic Crystals: Template‐Directed Directionally Solidified 3D Mesostructured AgCl–KCl Eutectic Photonic Crystals (Adv. Mater. 31/2015) 下载免费PDF全文
90.
Yonggui Wang Lars‐Oliver Heim Yeping Xu Gerd Buntkowsky Kai Zhang 《Advanced functional materials》2015,25(9):1434-1441
The use of bio‐based nanoscaled cellulose for the construction of novel functional materials has progressed rapidly over the past years. In comparison to most of studies starting with the hydrophilic nanoscaled cellulose, surface‐stearoylated cellulose nanoparticles (SS‐CNPs) are used in this report for the construction of multifunctional, responsive films. SS‐CNPs with an average size of 115 ± 0.5 nm are obtained after the surface‐modification of cellulose under heterogeneous conditions. Crystalline cellulose core is present within SS‐CNPs according to solid‐state 13C nuclear magnetic resonance (NMR) spectroscopy. SS‐CNPs show excellent dispersibility in nonpolar solvents and form temperature‐responsive organogels in tetrahydrofuran (THF) at low temperature or after long time storage at room temperature. Moreover, transparent and self‐standing films of SS‐CNPs from their THF‐suspension show solvent‐responsive surface wettability and responsive shape‐memory property. SS‐CNPs can also be used for the fabrication of nanocomposite films together with nonpolar compounds, such as (2‐stearoylaminoethyl) rhodamine B. Thus, these novel SS‐CNPs derived from sustainable cellulose fibers are promising candidates for the construction of novel functional materials. 相似文献