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Panagiotis Moulos Olga Papadodima Aristotelis Chatziioannou Heleni Loutrari Charis Roussos Fragiskos N Kolisis 《BMC medical genomics》2009,2(1):1-15
Background
DNA copy number alterations are frequently observed in ovarian cancer, but it remains a challenge to identify the most relevant alterations and the specific causal genes in those regions.Methods
We obtained high-resolution 500K SNP array data for 52 ovarian tumors and identified the most statistically significant minimal genomic regions with the most prevalent and highest-level copy number alterations (recurrent CNAs). Within a region of recurrent CNA, comparison of expression levels in tumors with a given CNA to tumors lacking that CNA and to whole normal ovary samples was used to select genes with CNA-specific expression patterns. A public expression array data set of laser capture micro-dissected (LCM) non-malignant fallopian tube epithelia and LCM ovarian serous adenocarcinoma was used to evaluate the effect of cell-type mixture biases.Results
Fourteen recurrent deletions were detected on chromosomes 4, 6, 9, 12, 13, 15, 16, 17, 18, 22 and most prevalently on X and 8. Copy number and expression data suggest several apoptosis mediators as candidate drivers of the 8p deletions. Sixteen recurrent gains were identified on chromosomes 1, 2, 3, 5, 8, 10, 12, 15, 17, 19, and 20, with the most prevalent gains localized to 8q and 3q. Within the 8q amplicon, PVT1, but not MYC, was strongly over-expressed relative to tumors lacking this CNA and showed over-expression relative to normal ovary. Likewise, the cell polarity regulators PRKCI and ECT2 were identified as putative drivers of two distinct amplicons on 3q. Co-occurrence analyses suggested potential synergistic or antagonistic relationships between recurrent CNAs. Genes within regions of recurrent CNA showed an enrichment of Cancer Census genes, particularly when filtered for CNA-specific expression.Conclusion
These analyses provide detailed views of ovarian cancer genomic changes and highlight the benefits of using multiple reference sample types for the evaluation of CNA-specific expression changes. 相似文献804.
Okan Ülgen Rami Shnaiderman Christian Zakian Vasilis Ntziachristos 《Journal of biophotonics》2021,14(7):e202000501
Optical fiber sensors can offer robust and miniaturized detection of wideband ultrasound, yielding high sensitivity and immunity to electromagnetic interference. However, the lack of cost-effective manufacturing methods prevents the disseminated use of these sensors in biomedical applications. In this study, we developed and optimized a simple method to create optical cavities with high-quality mirrors for acoustic sensing based on micro-manipulation of UV-curable optical adhesives and electroless chemical silver deposition. This approach enables the manufacturing of ultrasound sensors based on Fabry-Pérot interferometers on optical fiber tips with minimal production costs. Characterization and high-resolution optoacoustic imaging experiments show that the manufacturing process yielded a fiber sensor with a small NEP () over a broad detection bandwidth (25 MHz), generally outperforming conventional piezoelectric based transducers. We discuss how the new manufacturing process leads to a high-performance acoustic detector that, due to low cost, can be used as a disposable sensor. 相似文献
805.
Panagiotis Stathopoulos Serafim Papas Vassilios Tsikaris 《Journal of peptide science》2006,12(3):227-232
Decomposition of the resin linkers during TFA cleavage of the peptides in the Fmoc strategy leads to alkylation of sensitive amino acids. The C-terminal amide alkylation, reported for the first time, is shown to be a major problem in peptide amides synthesized on the Rink amide resin. This side reaction occurs as a result of the Rink amide linker decomposition under TFA treatment of the peptide resin. The use of 1,3-dimethoxybenzene in a cleavage cocktail prevents almost quantitatively formation of C-terminal N-alkylated peptide amides. Oxidized by-product in the tested Cys- and Met-containing peptides were not observed, even if thiols were not used in the cleavage mixture. 相似文献
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807.
Nektarios D. Charalambidis Stavros N. Bournazos Christos G. Zervas Panagiotis G. Katsoris Vassilis J. Marmaras 《Archives of insect biochemistry and physiology》1994,27(4):235-248
Larval Ceratitis capitata phenoloxidases (POs) from hemocytes, serum, integument, and fat body were analyzed. Two types of PO were recorded: the tyrosinase type found in hemocytes, serum, integument, and fat body and the laccase type found in integument. Tyrosinase from all larval tissues and integumental laccase as well, showed similarity in molecular weight (93 KDa), activation by Escherichia coli at 5 mM Ca2+, and reactivity to antibodies raised against serum tyrosinase. However, the enzymes differed with respect to their glycosylation and adhesiveness. The serum and integumental enzyme forms contain concanavalin A reacting material, whereas hemocyte and integumental tyrosinase(s) are adhesive. These differences in enzyme forms, although not influencing their substrate specificity, seem to give advantages to performing their function, i.e., the adhesive enzyme form facilitates the adherence to E. coli cell wall and hemocyte surface (unpublished data) while the glycosylated form facilitated the secretion into serum. © 1994 Wiley-Liss, Inc. 相似文献
808.
Panagiotis Samaras Thomas Pfammatter Bernhard C Pestalozzi 《International Seminars in Surgical Oncology : ISSO》2008,5(1):17
Pseudoaneurysms of the hepatic artery are a rare complication in patients with primary or secondary liver tumors treated with intra-arterial chemotherapy. We present two patients who developed this complication after placement of a catheter system into the gastroduodenal artery and initiation of regional chemotherapy with floxuridine. Diagnosis was made after symptomatic bleeding occurred, necessitating emergency angiography with coil embolization. Pseudoaneurysms usually occur after mechanical damage of the vessel wall, but the chemical toxicity of floxuridine may add to the development of vascular impairment. 相似文献
809.
Nikolaos B. Kyriakidis Maria Galiotou-Panayotou Anastasia Stavropoulou Panagiotis Athanasopoulos 《Biotechnology letters》1998,20(5):475-478
Maximum phytase activity in four legume species, lentils, chick peas, broad beans and runner beans, was reached after 6 days of germination for chick peas and 8 days for the rest of them. In all legumes, the increase in phytase activity was accompanied by a concomitant decrease in phytate content. After 10 days of germination the decrease in phytate varied from 83% in broad beans up to 64% in runner beans. 相似文献
810.
Panagiotis A. Tsonis Charles H. Washabaugh Katia Del Rio-Tsonis 《Development genes and evolution》1994,203(4):230-234
9-cis-retinoic acid has recently been found to be a high affinity ligand for the retinoic X receptor (RXR). RXRs are believed to be involved in metabolic activities rather than in morphogenetic ones. Interestingly, RXR has been found to form heterodimers involving other receptors from the steroid family, such as the thyroid hormone receptor, vitamin D receptor or retinoic acid receptors (RARs). In this paper we examined whether or not 9-cis-retinoic acid had any morphogenetic properties on the regenerating axolotl limb. It is shown that 9-cis-retinoic acid proximalized regenerating limbs and was somewhat more potent in this action than all-trans-retinoic acid. Based on these observations, the possible roles of other receptors during pattern formation is discussed.
Correspondence to: P.A. Tsonis 相似文献