216 results on '"L. Bittner"'
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2. A Holocene temperature (brGDGT) record from Garba Guracha, a high-altitude lake in Ethiopia
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L. Bittner, C. De Jonge, G. Gil-Romera, H. F. Lamb, J. M. Russell, and M. Zech
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Ecology ,QH540-549.5 ,Life ,QH501-531 ,Geology ,QE1-996.5 - Abstract
Eastern Africa has experienced strong climatic changes since the last deglaciation (15 000 years ago). The driving mechanisms and teleconnections of these spatially complex climate variations are yet not fully understood. Although previous studies on lake systems have enhanced our knowledge of Holocene precipitation variation in eastern Africa, relatively few studies have reconstructed the terrestrial temperature history of eastern Africa from lake archives. Here, we present (i) a new branched glycerol dialkyl glycerol tetraether (brGDGT) temperature calibration that includes Bale Mountains surface sediments and (ii) a quantitative record of mean annual air temperature (MAT) over the past 12 ka cal BP using brGDGTs in a sediment core collected from Garba Guracha (3950 m a.s.l.) in the Bale Mountains. After adding Bale Mountains surface sediment (n=11) data (Baxter et al., 2019) to the existing East African lake dataset, additional variation in 6-methyl brGDGTs was observed, which necessitated modifying the MBT5ME′ calibration (MBT denotes methylation of branched tetraethers) by adding 6-methyl brGDGT IIIa′ (resulting in the MBT Bale Mountains index, r2=0.93, p). Comparing the MBT5ME′ and the new MBT Bale Mountains index, our high-altitude Garba Guracha temperature record shows that warming occurred shortly after the Holocene onset when the temperature increased by more than 3.0 ∘C in less than 600 years. The highest temperatures prevailed between 9 and 6 ka cal BP, followed by a temperature decrease until 1.4 ka cal BP. The reconstructed temperature history is linked to supraregional climatic changes associated with insolation forcing and the African Humid Period (AHP), as well as with local anomalies associated with catchment deglaciation and hydrology.
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- 2022
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3. 18O analyses of bulk lipids as novel paleoclimate tool in loess research – a pilot study
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J. Labahn, L. Bittner, P. Hirschmann, C.-B. Roettig, D. Burghardt, B. Glaser, S. B. Marković, and M. Zech
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Geology ,QE1-996.5 - Abstract
The analysis of the stable oxygen isotopes 18O and 16O has revolutionized paleoclimate research since the middle of the last century. Particularly, δ18O of ice cores from Greenland and Antarctica is used as a paleotemperature proxy, and δ18O of deep-sea sediments is used as a proxy for global ice volume. Important terrestrial archives to which δ18O as a paleoclimate proxy is successfully applied are speleothems, lake sediments, or tree rings. By contrast, δ18O applications to loess–paleosol sequences (LPSs) are scarce. Here we present a first continuous δ18O record (n=50) for the LPS Crvenka in Serbia, southeastern Europe, spanning the last glacial–interglacial cycle (since 145 ka). From a methodological point of view, we took advantage of a recently proposed paleoclimate/paleohydrological proxy based on bulk δ18O analyses of plant-derived lipids. The Crvenka δ18Obulk lipid values range between −10.2 ‰ and +23.0 ‰ and are systematically more positive in the interglacial and interstadial (paleo-)soils corresponding to marine oxygen-isotope stage (MIS) 1, 3, and 5, compared to the loess layers (MIS 2, 4, and 6). Our Crvenka δ18Obulk lipid record provides no evidence for the occurrence of interstadials and stadials comparable to the Dansgaard–Oeschger events known from the Greenland δ18Oice core records. Concerning the interpretation of our Crvenka δ18Obulk lipid record, plant-derived lipids such as fatty acids and alcohols are certainly strongly influenced by climatic factors such as temperature (via δ18Oprecipitation) and relative air humidity (via 18O enrichment of leaf water due to evapotranspiration). However, pool effects in the form of non-water-correlated lipids such as sterols or the input of root-derived lipids need to be considered, too. Similarly, the input of soil-microbial lipids and oxygen exchange reactions represent uncertainties challenging quantitative paleoclimate/paleohydrological reconstructions based on δ18Obulk lipid analyses from LPSs.
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- 2022
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4. Chemotaxonomic patterns of vegetation and soils along altitudinal transects of the Bale Mountains, Ethiopia, and implications for paleovegetation reconstructions – Part II: lignin-derived phenols and leaf-wax-derived n-alkanes
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B. Lemma, B. Mekonnen, B. Glaser, W. Zech, S. Nemomissa, T. Bekele, L. Bittner, and M. Zech
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Geology ,QE1-996.5 - Abstract
Erica is a dominant vegetation type in many sub-afroalpine ecosystems, such as the Bale Mountains in Ethiopia. However, the past extent of Erica is not well known and climate versus anthropogenic influence on altitudinal shifts are difficult to assign unambiguously, especially during the Holocene. The main objective of the present study is to chemotaxonomically characterize the dominant plant species occurring in the Bale Mountains using lignin phenols and n-alkane biomarkers and to examine the potential of those biomarkers for reconstructing vegetation history. Fresh plant material, organic layer and mineral topsoil samples were collected along a northeastern and a southwestern altitudinal transect (4134–3870 and 4377–2550 m a.s.l., respectively). Lignin-derived vanillyl, syringyl and cinnamyl phenols were analyzed using the cupric oxide oxidation method. Leaf-wax-derived n-alkanes were extracted and purified using Soxhlet and aminopropyl columns. Individual lignin phenols and n-alkanes were separated by gas-chromatography and detected by mass spectrometry and flame ionization detection, respectively. We found that the relative contributions of vanillyl, syringyl and cinnamyl phenols allow us to chemotaxonomically distinguish contemporary plant species of the Bale Mountains. Erica in particular is characterized by relatively high cinnamyl contributions of >40 %. However, litter degradation strongly decreases the lignin phenol concentrations and completely changes the lignin phenol patterns. Relative cinnamyl contributions in soils under Erica were %, while soils that developed under Poaceae (Festuca abyssinica) exhibited relative cinnamyl contributions of >40 %. Similarly, long-chain n-alkanes extracted from the leaf waxes allowed for differentiation between Erica versus Festuca abyssinica and Alchemilla, based on lower C31 ∕ C29 ratios in Erica. However, this characteristic plant pattern was also lost due to degradation in the respective O layers and Ah horizons. In conclusion, although in modern-day plant samples a chemotaxonomic differentiation is possible, soil degradation processes seem to render the proxies unusable for the reconstruction of the past extent of Erica on the Sanetti Plateau, Bale Mountains, Ethiopia. This finding is of high relevance beyond our case study.
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- 2019
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5. Effect of elevated CO2 on the dynamics of particle-attached and free-living bacterioplankton communities in an Arctic fjord
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S. Romac, U. Riebesell, J. I. Nissimov, L. Bittner, J. Gilbert, J. La Roche, A.-S. Roy, H. Schunck, A. Wichels, G. Gerdts, J. Piontek, M. Sperling, and A. Engel
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Ecology ,QH540-549.5 ,Life ,QH501-531 ,Geology ,QE1-996.5 - Abstract
In the frame of the European Project on Ocean Acidification (EPOCA), the response of an Arctic pelagic community (pCO2 was investigated. For this purpose 9 large-scale in situ mesocosms were deployed in Kongsfjorden, Svalbard (78°56.2´ N, 11°53.6´ E), in 2010. The present study investigates effects on the communities of particle-attached (PA; >3 μm) and free-living (FL; < 3 μm > 0.2 μm) bacteria by Automated Ribosomal Intergenic Spacer Analysis (ARISA) in 6 of the mesocosms, ranging from 185 to 1050 μatm initial pCO2, and the surrounding fjord. ARISA was able to resolve, on average, 27 bacterial band classes per sample and allowed for a detailed investigation of the explicit richness and diversity. Both, the PA and the FL bacterioplankton community exhibited a strong temporal development, which was driven mainly by temperature and phytoplankton development. In response to the breakdown of a picophytoplankton bloom, numbers of ARISA band classes in the PA community were reduced at low and medium CO2 (~ 185–685 μatm) by about 25%, while they were more or less stable at high CO2 (~ 820–1050 μatm). We hypothesise that enhanced viral lysis and enhanced availability of organic substrates at high CO2 resulted in a more diverse PA bacterial community in the post-bloom phase. Despite lower cell numbers and extracellular enzyme activities in the post-bloom phase, bacterial protein production was enhanced in high CO2 mesocosms, suggesting a positive effect of community richness on this function and on carbon cycling by bacteria.
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- 2013
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6. Ocean acidification shows negligible impacts on high-latitude bacterial community structure in coastal pelagic mesocosms
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A.-S. Roy, S. M. Gibbons, H. Schunck, S. Owens, J. G. Caporaso, M. Sperling, J. I. Nissimov, S. Romac, L. Bittner, M. Mühling, U. Riebesell, J. LaRoche, and J. A. Gilbert
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Ecology ,QH540-549.5 ,Life ,QH501-531 ,Geology ,QE1-996.5 - Abstract
The impact of ocean acidification and carbonation on microbial community structure was assessed during a large-scale in situ costal pelagic mesocosm study, included as part of the EPOCA 2010 Arctic campaign. The mesocosm experiment included ambient conditions (fjord) and nine mesocosms with pCO2 levels ranging from ~145 to ~1420 μatm. Samples for the present study were collected at ten time points (t–1, t1, t5, t7, t12, t14, t18, t22, t26 to t28) in seven treatments (ambient fjord (~145), 2 × ~185, ~270, ~685, ~820, ~1050 μatm) and were analysed for "small" and "large" size fraction microbial community composition using 16S RNA (ribosomal ribonucleic acid) amplicon sequencing. This high-throughput sequencing analysis produced ~20 000 000 16S rRNA V4 reads, which comprised 7000 OTUs. The main variables structuring these communities were sample origins (fjord or mesocosms) and the community size fraction (small or large size fraction). The community was significantly different between the unenclosed fjord water and enclosed mesocosms (both control and elevated CO2 treatments) after nutrients were added to the mesocosms, suggesting that the addition of nutrients is the primary driver of the change in mesocosm community structure. The relative importance of each structuring variable depended greatly on the time at which the community was sampled in relation to the phytoplankton bloom. The sampling strategy of separating the small and large size fraction was the second most important factor for community structure. When the small and large size fraction bacteria were analysed separately at different time points, the only taxon pCO2 was found to significantly affect were the Gammaproteobacteria after nutrient addition. Finally, pCO2 treatment was found to be significantly correlated (non-linear) with 15 rare taxa, most of which increased in abundance with higher CO2.
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- 2013
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7. Supplementary Data 4 from Integrating Global Gene Expression and Radiation Survival Parameters across the 60 Cell Lines of the National Cancer Institute Anticancer Drug Screen
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Albert J. Fornace, Paul S. Meltzer, Michael L. Bittner, Jeffrey M. Trent, John N. Weinstein, Dominic A. Scudiero, Yidong Chen, Mark Reimers, Jaeyong Ahn, Christine A. Koch-Paiz, R. Anthony Lee, Lisa C. Vinikoor, Khanh T. Do, and Sally A. Amundson
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Supplementary Data 4 from Integrating Global Gene Expression and Radiation Survival Parameters across the 60 Cell Lines of the National Cancer Institute Anticancer Drug Screen
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- 2023
8. Supplementary Table 3 from A Cell Proliferation and Chromosomal Instability Signature in Anaplastic Thyroid Carcinoma
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Massimo Santoro, Michael L. Bittner, Alfredo Fusco, Rosa Marina Melillo, Anna Maria Cirafici, Maria Domenica Castellone, Fulvio Basolo, Paolo Miccoli, Clara Ugolini, Corrado Garbi, Yuan Jiang, Paolo Salerno, Tito Claudio Nappi, and Giuliana Salvatore
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Supplementary Table 3 from A Cell Proliferation and Chromosomal Instability Signature in Anaplastic Thyroid Carcinoma
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- 2023
9. Supplementary Data 3 from Integrating Global Gene Expression and Radiation Survival Parameters across the 60 Cell Lines of the National Cancer Institute Anticancer Drug Screen
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Albert J. Fornace, Paul S. Meltzer, Michael L. Bittner, Jeffrey M. Trent, John N. Weinstein, Dominic A. Scudiero, Yidong Chen, Mark Reimers, Jaeyong Ahn, Christine A. Koch-Paiz, R. Anthony Lee, Lisa C. Vinikoor, Khanh T. Do, and Sally A. Amundson
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Supplementary Data 3 from Integrating Global Gene Expression and Radiation Survival Parameters across the 60 Cell Lines of the National Cancer Institute Anticancer Drug Screen
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- 2023
10. Supplementary Data 2 from Integrating Global Gene Expression and Radiation Survival Parameters across the 60 Cell Lines of the National Cancer Institute Anticancer Drug Screen
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Albert J. Fornace, Paul S. Meltzer, Michael L. Bittner, Jeffrey M. Trent, John N. Weinstein, Dominic A. Scudiero, Yidong Chen, Mark Reimers, Jaeyong Ahn, Christine A. Koch-Paiz, R. Anthony Lee, Lisa C. Vinikoor, Khanh T. Do, and Sally A. Amundson
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Supplementary Data 2 from Integrating Global Gene Expression and Radiation Survival Parameters across the 60 Cell Lines of the National Cancer Institute Anticancer Drug Screen
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- 2023
11. Supplementary Figure 1 from A Cell Proliferation and Chromosomal Instability Signature in Anaplastic Thyroid Carcinoma
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Massimo Santoro, Michael L. Bittner, Alfredo Fusco, Rosa Marina Melillo, Anna Maria Cirafici, Maria Domenica Castellone, Fulvio Basolo, Paolo Miccoli, Clara Ugolini, Corrado Garbi, Yuan Jiang, Paolo Salerno, Tito Claudio Nappi, and Giuliana Salvatore
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Supplementary Figure 1 from A Cell Proliferation and Chromosomal Instability Signature in Anaplastic Thyroid Carcinoma
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- 2023
12. Data from Integrating Global Gene Expression and Radiation Survival Parameters across the 60 Cell Lines of the National Cancer Institute Anticancer Drug Screen
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Albert J. Fornace, Paul S. Meltzer, Michael L. Bittner, Jeffrey M. Trent, John N. Weinstein, Dominic A. Scudiero, Yidong Chen, Mark Reimers, Jaeyong Ahn, Christine A. Koch-Paiz, R. Anthony Lee, Lisa C. Vinikoor, Khanh T. Do, and Sally A. Amundson
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The 60 cell lines of the National Cancer Institute Anticancer Drug Screen (NCI-60) constitute the most extensively characterized in vitro cancer cell model. They have been tested for sensitivity to more than 100,000 potential chemotherapy agents and have been profiled extensively at the DNA, RNA, protein, functional, and pharmacologic levels. We have used the NCI-60 cell lines and three additional lines to develop a database of responses of cancer cells to ionizing radiation. We compared clonogenic survival, apoptosis, and gene expression response by microarray. Although several studies have profiled relative basal gene expression in the NCI-60, this is the first comparison of large-scale gene expression changes in response to genotoxic stress. Twenty-two genes were differentially regulated in cells with low survival after 2-Gy γ-rays; 14 genes identified lines more sensitive to 8 Gy. Unlike reported basal gene expression patterns, changes in expression in response to radiation showed little tissue-of-origin effect, except for differentiating the lymphoblastoid cell lines from other cell types. Basal expression patterns, however, discriminated well between radiosensitive and more resistant lines, possibly being more informative than radiation response signatures. The most striking patterns in the radiation data were a set of genes up-regulated preferentially in the p53 wild-type lines and a set of cell cycle regulatory genes down-regulated across the entire NCI-60 panel. The response of those genes to γ-rays seems to be unaffected by the myriad of genetic differences across this diverse cell set; it represents the most penetrant gene expression response to ionizing radiation yet observed. [Cancer Res 2008;68(2):415–24]
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- 2023
13. Supplementary Table 4 from A Cell Proliferation and Chromosomal Instability Signature in Anaplastic Thyroid Carcinoma
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Massimo Santoro, Michael L. Bittner, Alfredo Fusco, Rosa Marina Melillo, Anna Maria Cirafici, Maria Domenica Castellone, Fulvio Basolo, Paolo Miccoli, Clara Ugolini, Corrado Garbi, Yuan Jiang, Paolo Salerno, Tito Claudio Nappi, and Giuliana Salvatore
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Supplementary Table 4 from A Cell Proliferation and Chromosomal Instability Signature in Anaplastic Thyroid Carcinoma
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- 2023
14. Supplementary Table 5 from A Cell Proliferation and Chromosomal Instability Signature in Anaplastic Thyroid Carcinoma
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Massimo Santoro, Michael L. Bittner, Alfredo Fusco, Rosa Marina Melillo, Anna Maria Cirafici, Maria Domenica Castellone, Fulvio Basolo, Paolo Miccoli, Clara Ugolini, Corrado Garbi, Yuan Jiang, Paolo Salerno, Tito Claudio Nappi, and Giuliana Salvatore
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Supplementary Table 5 from A Cell Proliferation and Chromosomal Instability Signature in Anaplastic Thyroid Carcinoma
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- 2023
15. Supplementary Table 1 from A Cell Proliferation and Chromosomal Instability Signature in Anaplastic Thyroid Carcinoma
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Massimo Santoro, Michael L. Bittner, Alfredo Fusco, Rosa Marina Melillo, Anna Maria Cirafici, Maria Domenica Castellone, Fulvio Basolo, Paolo Miccoli, Clara Ugolini, Corrado Garbi, Yuan Jiang, Paolo Salerno, Tito Claudio Nappi, and Giuliana Salvatore
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Supplementary Table 1 from A Cell Proliferation and Chromosomal Instability Signature in Anaplastic Thyroid Carcinoma
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- 2023
16. Supplementary Table 2 from A Cell Proliferation and Chromosomal Instability Signature in Anaplastic Thyroid Carcinoma
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Massimo Santoro, Michael L. Bittner, Alfredo Fusco, Rosa Marina Melillo, Anna Maria Cirafici, Maria Domenica Castellone, Fulvio Basolo, Paolo Miccoli, Clara Ugolini, Corrado Garbi, Yuan Jiang, Paolo Salerno, Tito Claudio Nappi, and Giuliana Salvatore
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Supplementary Table 2 from A Cell Proliferation and Chromosomal Instability Signature in Anaplastic Thyroid Carcinoma
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- 2023
17. Supplementary Figure 1 from Integrating Global Gene Expression and Radiation Survival Parameters across the 60 Cell Lines of the National Cancer Institute Anticancer Drug Screen
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Albert J. Fornace, Paul S. Meltzer, Michael L. Bittner, Jeffrey M. Trent, John N. Weinstein, Dominic A. Scudiero, Yidong Chen, Mark Reimers, Jaeyong Ahn, Christine A. Koch-Paiz, R. Anthony Lee, Lisa C. Vinikoor, Khanh T. Do, and Sally A. Amundson
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Supplementary Figure 1 from Integrating Global Gene Expression and Radiation Survival Parameters across the 60 Cell Lines of the National Cancer Institute Anticancer Drug Screen
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- 2023
18. Data from A Cell Proliferation and Chromosomal Instability Signature in Anaplastic Thyroid Carcinoma
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Massimo Santoro, Michael L. Bittner, Alfredo Fusco, Rosa Marina Melillo, Anna Maria Cirafici, Maria Domenica Castellone, Fulvio Basolo, Paolo Miccoli, Clara Ugolini, Corrado Garbi, Yuan Jiang, Paolo Salerno, Tito Claudio Nappi, and Giuliana Salvatore
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Here, we show that the anaplastic thyroid carcinoma (ATC) features the up-regulation of a set of genes involved in the control of cell cycle progression and chromosome segregation. This phenotype differentiates ATC from normal tissue and from well-differentiated papillary thyroid carcinoma. Transcriptional promoters of the ATC up-regulated genes are characterized by a modular organization featuring binding sites for E2F and NF-Y transcription factors and cell cycle–dependent element (CDE)/cell cycle gene homology region (CHR) cis-regulatory elements. Two protein kinases involved in cell cycle regulation, namely, Polo-like kinase 1 (PLK1) and T cell tyrosine kinase (TTK), are part of the gene set that is up-regulated in ATC. Adoptive overexpression of p53, p21 (CIP1/WAF1), and E2F4 down-regulated transcription from the PLK1 and TTK promoters in ATC cells, suggesting that these genes might be under the negative control of tumor suppressors of the p53 and pRB families. ATC, but not normal thyroid, cells depended on PLK1 for survival. RNAi-mediated PLK1 knockdown caused cell cycle arrest associated with 4N DNA content and massive mitotic cell death. Thus, thyroid cell anaplastic transformation is accompanied by the overexpression of a cell proliferation/genetic instability-related gene cluster that includes PLK1 kinase, which is a potential molecular target for ATC treatment. [Cancer Res 2007;67(21):10148–57]
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- 2023
19. Supplementary Data 1 from Integrating Global Gene Expression and Radiation Survival Parameters across the 60 Cell Lines of the National Cancer Institute Anticancer Drug Screen
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Albert J. Fornace, Paul S. Meltzer, Michael L. Bittner, Jeffrey M. Trent, John N. Weinstein, Dominic A. Scudiero, Yidong Chen, Mark Reimers, Jaeyong Ahn, Christine A. Koch-Paiz, R. Anthony Lee, Lisa C. Vinikoor, Khanh T. Do, and Sally A. Amundson
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Supplementary Data 1 from Integrating Global Gene Expression and Radiation Survival Parameters across the 60 Cell Lines of the National Cancer Institute Anticancer Drug Screen
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- 2023
20. Effect of a multimodal pain management protocol and age on wound healing after thermal disbudding of female German Holstein calves
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J, Kretschmann, L, Früchtl, M-L, Fischer, M, Kaiser, H, Müller, J, Spilke, N, Mielenz, G, Möbius, L, Bittner-Schwerda, I, Steinhöfel, W, Baumgartner, and A, Starke
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Wound Healing ,General Veterinary ,Animals ,Pain ,Pain Management ,Cattle ,Female ,Clinical Trials, Veterinary as Topic ,Prospective Studies ,Horns - Abstract
Hot-iron disbudding of calves is a stressful and painful procedure and leaves a burn wound. Pain management procedures and the effects of hot-iron disbudding on biochemical markers of pain perception and stress response have been widely investigated in recent years. The aim of this study was to investigate the potential effects of pain management and age of the calf on the healing of burn wounds caused by disbudding. 327 healthy female German Holstein calves were included in this randomised, triple-blinded, prospective study. Calves were either disbudded at the age of four to 10 or 15 to 28 days using a gas-powered hot iron. Each calf was randomly allocated to one of nine possible treatment groups (BG). All calves received either the active ingredients to be tested (xylazine hydrochloride with 0.2 or 0.05 mg / kg body mass (BM) intramuscular for sedation, procaine hydrochloride (2 %) each 8 ml locally on both sides subcutaneously (SC) to the cornual nerves, meloxicam with 0,5 mg / kg BM SC for anti-inflammatory purposes) or an identical amount of saline solution (placebo). Calves in the group `thermE` and `ScheinE` received only placebo. In group `ScheinE` disbudding was simulated and in `thermE` it was carried out. The calves were clinically monitored starting one day before and ending 28 days after the procedure and the burn wounds were assessed. Both the rectal temperature and parameters of wound healing changed significantly during the study period and had characteristic profiles over time. Wound healing was not influenced by the different analgesic protocols, indicating that a multimodal analgesia does not pose a risk for wound healing after thermal disbudding. There were no observed differences between the age groups. The results of this study show, that disbudding of young calves and a multimodal pain management protocol does not affect wound healing in calves.Die thermische Zerstörung der Hornanlage (ZHA) von Kälbern stellt einen Eingriff dar, welcher mit Schmerz und Stress verbunden ist und eine Verbrennungswunde hinterlässt. Verschiedene Verfahren der Schmerzausschaltung sowie der Einfluss der thermischen ZHA auf Marker der Schmerz- und Stressreaktion wurden bereits evaluiert. Ziel der vorliegenden Studie war es zu prüfen, inwieweit das Schmerzmanagement selbst oder das Alter der Kälber die Wundheilung thermisch bedingter Wunden nach ZHA beeinflusst. In die randomisierte, dreifach verblindete, prospektive Studie wurden 327 gesunde, weibliche Deutsch-Holstein-Kälber einbezogen. Die ZHA erfolgte entweder zwischen dem vierten und 10. oder dem 15. und 28. Lebenstag mit einem gasbetriebenen Enthornungsgerät. Jedes Kalb wurde einer von neun Behandlungsgruppen (BG) zugelost. Alle Kälber bekamen entweder die zu testenden Wirkstoffe (Xylazinhydrochlorid mit 0,2 oder 0,05 mg/kg Körpermasse (KM) zur Sedation intramuskulär, Procainhydrochlorid (2 %) je 8 ml lokal beidseitig subkutan (SC) an die Rr. cornuales, Meloxicam mit 0,5 mg/kg KM SC zur Entzündungshemmung/Analgesie) oder eine identische Menge an isotoner Kochsalzlösung (Placebo) injiziert. Kälber der Gruppe `thermE` und `ScheinE` erhielten nur Placebo, bei `ScheinE` wurde die ZHA simuliert, bei `thermE` durchgeführt. Die Gruppe `Melo` erhielt nur Meloxicam, `LA` nur Procainhydrochlorid, `Melo-LA` Meloxicam + Procainhydrochlorid, `Seda 0,2` nur Xylazinhydrochlorid, `Seda 0,05-Melo` und `Seda 0,2-Melo ` (Xylazinhydrochlorid + Meloxicam), und `Seda 0,2-Melo-LA` alle zu testenden Wirkstoffe. Die Kälber wurden von einem Tag vor bis 28 Tage nach dem Eingriff klinisch überwacht und die Wunden befundet. Sowohl die inneren Körpertemperatur (IKT) als auch die Merkmale der Wundheilung unterschieden sich signifikant zwischen den einzelnen Untersuchungstagen und zeigten einen zeitlichen Verlauf. Die Wundheilung wurde durch die verschiedenen Analgetika oder deren Kombinationen nicht beeinflusst, eine multimodale Analgesie stellt demnach kein Risiko für die Wundheilung nach ZHA unter Praxisbedingungen dar. Zwischen den Altersgruppen wurden keine Unterschiede in der Wundheilung beobachtet. Die ZHA von Kälbern kann unter Praxisbedingungen demnach bereits früh und unter Ausschöpfung aller analgetischen Möglichkeiten erfolgen.L’ébourgeonnage thermique des veaux est une procédure stressante et douloureuse qui laisse une brûlure. Les procédures de gestion de la douleur et les effets de l’ébourgeonnage thermique sur les marqueurs biochimiques de la perception de la douleur et de la réponse au stress ont été largement étudiés ces dernières années. Le but de cette étude était d’étudier les effets potentiels de la gestion de la douleur et de l’âge du veau sur la cicatrisation des brûlures causées par l’ébourgeonnage. 327 veaux Holstein allemands femelles en bonne santé ont été inclus dans cette étude prospective randomisée en triple aveugle. Les veaux ont été soit ébourgeonnés à l’âge de 4 à 10 jours ou de 15 à 28 jours à l’aide d’un thermocautère à gaz. Chaque veau a été réparti au hasard dans l’un des neuf groupes de traitement possibles (BG). Tous les veaux ont reçu soit les principes actifs à tester (chlorhydrate de xylazine à 0,2 ou 0,05 mg/kg de masse corporelle (BM) par voie intramusculaire pour sédation, chlorhydrate de procaïne (2 %) 8 ml localement des deux côtés par voie sous-cutanée (SC) jusqu’aux nerfs cornuaux , méloxicam à 0,5 mg/kg de masse corporelle SC à visée anti-inflammatoire) ou une quantité identique de solution saline (placebo). Les veaux du groupe « thermE » et « ScheinE » ont reçu uniquement un placebo. Dans le groupe ‹ScheinE’ l’ébourgeonnage a été simulé et dans ‘thermE’ il a été réalisé. Le groupe « Melo » n’a reçu que du méloxicam, le groupe « LA » uniquement du chlorhydrate de procaïne, le grpoupe « Melo-LA » du méloxicam + chlorhydrate de procaïne, le groupe « Seda 0,2 » uniquement du chlorhydrate de xylazine, les groupes « Seda 0,05-Melo » et« Seda 0,2 -Melo » duchlorhydrate de xylazine et du méloxicam), et le groupe « Seda 0,2-Melo-LA » toutes les substances actives à tester. Les veaux ont été suivis cliniquement en commençant un jour avant et en terminant 28 jours après la procédure et les brûlures ont été évaluées. La température rectale et les paramètres de cicatrisation des plaies ont changé de manière significative au cours de la période d’étude et ont eu des profils caractéristiques au fil du temps. La cicatrisation n’a pas été influencée par les différents protocoles analgésiques, ce qui indique qu’une analgésie multimodale ne présente pas de risque quant à la cicatrisation après ébourgeonnage thermique. Aucune différence n’a été observée entre les groupes d’âge. Les résultats de cette étude montrent que l’ébourgeonnage des jeunes veaux et un protocole multimodal de gestion de la douleur n’affectent pas la cicatrisation des veaux.La decornazione termica dei vitelli è una procedura che è associata a dolore e stress e lascia una ferita da ustione. Diversi metodi di analgesia e l’influenza della decornazione termica sui marcatori del dolore e della risposta allo stress sono già stati valutati. Lo scopo del presente studio era quello di esaminare la misura in cui, la gestione del dolore stesso o l’età dei vitelli, influenzi la guarigione delle ferite provocate dopo la decornazione termica. Lo studio randomizzato, in triplo cieco e prospettico ha incluso 327 vitelli sani di razza Holstein tedesca. La decornazione è stata eseguita tra il quarto e il decimo o il quindicesimo e il ventottesimo giorno di vita utilizzando un dispositivo di decornazione a gas. Ogni vitello è stato assegnato a uno dei nove gruppi di trattamento (GT). A tutti i vitelli sono stati iniettati o gli agenti da testare (xilazina cloridrato a 0,2 o 0,05 mg/kg di massa corporea (MC) per via intramuscolare per la sedazione, procaina cloridrato (2 %) 8 ml ciascuno per via locale bilaterale sottocutanea (SC) ai rr. cornuales, meloxicam a 0,5 mg/kg KM SC per antinfiammatorio/analgesia) o una quantità identica di soluzione salina isotonica (placebo). I vitelli nei gruppi `thermE` e `ScheinE` hanno ricevuto solo placebo; la decornazione è stata simulata in `ScheinE` ed eseguita in `thermE`. Il gruppo `Melo` ha ricevuto solo meloxicam, `LA` solo procaina cloridrato, `Melo-LA` meloxicam + procaina cloridrato, `Seda 0,2` solo xilazina cloridrato, `Seda 0,05-Melo` e `Seda 0,2-Melo` (xilazina cloridrato + meloxicam), e `Seda 0,2-Melo-LA` tutti gli agenti da testare. I vitelli sono stati monitorati clinicamente da un giorno prima a 28 giorni dopo la procedura e sono state valutate le ferite. Sia la temperatura corporea interna (TCI) che le caratteristiche di guarigione della ferita differivano significativamente tra i giorni di studio e mostravano un andamento temporale. La guarigione della ferita non è stata influenzata dai diversi analgesici o dalle loro combinazioni; l’analgesia multimodale non rappresenta quindi un rischio per la guarigione della ferita dopo la decornazione in condizioni reali. Non sono state osservate differenze nella guarigione delle ferite tra i gruppi di età. Pertanto, la decornazione dei vitelli in condizioni reali può essere eseguita presto e con l’esaurimento di tutte le possibilità analgesiche.
- Published
- 2021
21. Comprehensive live-cell imaging analysis of cryptotanshinone and synergistic drug-screening effects in various human and canine cancer cell lines
- Author
-
Heather Wilson-Robles, Rosana Lopes, Aniruddha Datta, Chao Sima, Michael L. Bittner, and Jianping Hua
- Subjects
0301 basic medicine ,Skin Neoplasms ,Cell ,Cancer Treatment ,Apoptosis ,Salvia miltiorrhiza ,Lung and Intrathoracic Tumors ,0302 clinical medicine ,Neoplasms ,Breast Tumors ,Medicine and Health Sciences ,Skin Tumors ,Early Detection of Cancer ,Multidisciplinary ,Cell Death ,Melanoma ,Liver Diseases ,medicine.anatomical_structure ,Oncology ,Cell Processes ,030220 oncology & carcinogenesis ,Medicine ,Osteosarcoma ,Research Article ,Signal Transduction ,STAT3 Transcription Factor ,Cell Survival ,Science ,Dermatology ,Gastroenterology and Hepatology ,03 medical and health sciences ,Pancreatic Cancer ,Breast cancer ,Dogs ,Pancreatic cancer ,Cell Line, Tumor ,Breast Cancer ,Gastrointestinal Tumors ,medicine ,Animals ,Humans ,Colorectal Cancer ,business.industry ,Carcinoma ,Cancer ,Cancers and Neoplasms ,Biology and Life Sciences ,Cell Biology ,Hepatocellular Carcinoma ,Phenanthrenes ,medicine.disease ,030104 developmental biology ,Cancer cell ,Cancer research ,business - Abstract
Background Several studies have highlighted both the extreme anticancer effects of Cryptotanshinone (CT), a Stat3 crippling component from Salvia miltiorrhiza, as well as other STAT3 inhibitors to fight cancer. Methods Data presented in this experiment incorporates 2 years of in vitro studies applying a comprehensive live-cell drug-screening analysis of human and canine cancer cells exposed to CT at 20 μM concentration, as well as to other drug combinations. As previously observed in other studies, dogs are natural cancer models, given to their similarity in cancer genetics, epidemiology and disease progression compared to humans. Results Results obtained from several types of human and canine cancer cells exposed to CT and varied drug combinations, verified CT efficacy at combating cancer by achieving an extremely high percentage of apoptosis within 24 hours of drug exposure. Conclusions CT anticancer efficacy in various human and canine cancer cell lines denotes its ability to interact across different biological processes and cancer regulatory cell networks, driving inhibition of cancer cell survival.
- Published
- 2021
22. Targeting oncogenic mutations in colorectal cancer using cryptotanshinone
- Author
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Michael L. Bittner, Rosana Lopes, Jianping Hua, Chao Sima, Aniruddha Datta, and Haswanth Vundavilli
- Subjects
0301 basic medicine ,Colorectal cancer ,Carcinogenesis ,Cancer Treatment ,Gene Expression ,Apoptosis ,medicine.disease_cause ,Biochemistry ,Suppressor Genes ,0302 clinical medicine ,Medicine and Health Sciences ,Medicine ,Multidisciplinary ,Cell Death ,Pharmaceutics ,Gene Expression Regulation, Neoplastic ,Crosstalk (biology) ,Oncology ,Cell Processes ,030220 oncology & carcinogenesis ,Colorectal Neoplasms ,HT29 Cells ,Research Article ,Signal Transduction ,Programmed cell death ,medicine.medical_specialty ,Science ,Tumor Suppressor Genes ,03 medical and health sciences ,Drug Therapy ,Gene Types ,Molecular genetics ,DNA-binding proteins ,Genetics ,Humans ,Gene Regulation ,Transcription factor ,Cell Proliferation ,Colorectal Cancer ,business.industry ,Cancer ,Cancers and Neoplasms ,Biology and Life Sciences ,Proteins ,Cell Biology ,Phenanthrenes ,medicine.disease ,HCT116 Cells ,digestive system diseases ,Regulatory Proteins ,030104 developmental biology ,Mutation ,Cancer research ,business ,Transcription Factors - Abstract
Colorectal cancer (CRC) is one of the most prevalent types of cancer in the world and ranks second in cancer deaths in the US. Despite the recent improvements in screening and treatment, the number of deaths associated with CRC is still very significant. The complexities involved in CRC therapy stem from multiple oncogenic mutations and crosstalk between abnormal pathways. This calls for using advanced molecular genetics to understand the underlying pathway interactions responsible for this cancer. In this paper, we construct the CRC pathway from the literature and using an existing public dataset on healthy vs tumor colon cells, we identify the genes and pathways that are mutated and are possibly responsible for the disease progression. We then introduce drugs in the CRC pathway, and using a boolean modeling technique, we deduce the drug combinations that produce maximum cell death. Our theoretical simulations demonstrate the effectiveness of Cryptotanshinone, a traditional Chinese herb derivative, achieved by targeting critical oncogenic mutations and enhancing cell death. Finally, we validate our theoretical results using wet lab experiments on HT29 and HCT116 human colorectal carcinoma cell lines.
- Published
- 2021
23. Targeting Oncogenic Mutations in Colorectal Cancer using Cryptotanshinone
- Author
-
Aniruddha Datta, Jianping Hua, Chao Sima, Michael L. Bittner, Rosana Lopes, and Haswanth Vundavilli
- Subjects
medicine.medical_specialty ,Programmed cell death ,business.industry ,Colorectal cancer ,Disease progression ,medicine.disease ,digestive system diseases ,CRC Pathway ,Crosstalk (biology) ,Tumor colon ,Molecular genetics ,medicine ,Cancer research ,business ,Gene - Abstract
Colorectal cancer (CRC) is one of the most prevalent types of cancer in the world and ranks second in cancer deaths in the US. Despite the recent improvements in screening and treatment, the number of deaths associated with CRC is still very significant. The complexities involved in CRC therapy stem from multiple oncogenic mutations and crosstalk between abnormal pathways. This calls for using advanced molecular genetics to understand the underlying pathway interactions responsible for this cancer. In this paper, we construct the CRC pathway from the literature and using an existing public dataset on healthy vs tumor colon cells, we identify the genes/pathways that are mutated and are possibly responsible for the disease progression. We then introduce drugs in the CRC pathway, and using a boolean modeling technique, we deduce the drug combinations that produce maximum cell death. Our theoretical simulations demonstrate the effectiveness of Cryptotanshinone, a traditional Chinese herb derivative, achieved by targeting critical oncogenic mutations and enhancing cell death. Finally, we validate our theoretical results using wet lab experiments on HT29 and HCT116 human colorectal carcinoma cell lines.
- Published
- 2020
24. Evaluation of Two Novel Therapeutics Against Human and Canine Osteosarcoma
- Author
-
Michael L. Bittner, Heather Wilson-Robles, Tasha Miller, Jianping Hua, Chao Sima, and Milana Cypert
- Subjects
Text mining ,business.industry ,Cancer research ,Medicine ,business ,Canine Osteosarcoma - Abstract
Background: Osteosarcoma (OS) is the most common primary bone tumor in both humans and canines. This tumor has an aggressive course leading to the development of metastatic lesions in most patients diagnosed with this disease. Two new novel agents, MLN9708 and SH4-54, work as a proteasome inhibitor and a STAT3 inhibitor, respectively. Targets of these drugs have been shown to be overexpressed in OS in both species. Methods: Two human and two canine OS cell lines were exposed in vitro to both drugs alone and in combination. The number of cells undergoing apoptosis, as well as the number of cells capable of invasion through a matrigel basement membrane was evaluated after exposure to the drugs. Additionally, PCR and Western blots of downstream targets were evaluated. Finally, both drugs were tested against each cell line in an in vivo murine xenograft model. Results: All four cell lines were sensitive to MLN9708, one of the human cell lines and both canine cell lines were resistant to SH4-54. MLN9708 was also better at inhibiting invasion in three of the four cell lines. In the murine xenografts MLN9708 inhibited growth and metastasis in 143B (human OS) and the combination inhibited growth in the canine OS cell line (MCKOS). Conclusions: Though SH4-54 demonstrated robust cell killing in 143B in vitro, MLN9708 demonstrated broader activity across species for the treatment of OS. Further investigation into this drug is warranted as a treatment for OS. Combination of this drug with a STAT3 inhibitor may be worthwhile in canine OS.
- Published
- 2020
25. Comprehensive Live-cell Imaging Analysis of Cryptotanshinone and Synergistic Drug-Screening Effects in Various Human and Canine Cancer Cell Lines
- Author
-
Aniruddha Datta, Chao Sima, Michael L. Bittner, Rosana Lopes, Jianping Hua, and Heather Wilson-Robles
- Subjects
Drug ,business.industry ,media_common.quotation_subject ,Cell ,Cancer ,medicine.disease ,Salvia miltiorrhiza ,In vitro ,medicine.anatomical_structure ,Apoptosis ,Cell culture ,Cancer cell ,medicine ,Cancer research ,business ,media_common - Abstract
BackgroundSeveral studies have highlighted both the extreme anticancer effects of Cryptotanshinone (CT), a Stat3 crippling component from Salvia miltiorrhiza, as well as other STAT3 inhibitors to fight cancer.MethodsData presented in this experiment incorporates 2 years of in vitro studies applying a comprehensive live-cell drug-screening analysis of human and canine cancer cells exposed to CT at 20 μM concentration, as well as to other drug combinations. As previously observed in other studies, dogs are natural cancer models, given to their similarity in cancer genetics, epidemiology and disease progression compared to humans.ResultsResults obtained from several types of human and canine cancer cells exposed to CT and varied drug combinations, verified CT efficacy at combating cancer by achieving an extremely high percentage of apoptosis within 24 hours of drug exposure.ConclusionsCT anticancer efficacy in various human and canine cancer cell lines denotes its ability to interact across different biological processes and cancer regulatory cell networks, driving inhibition of cancer cell survival.
- Published
- 2020
26. Aerodynamic and aeroelastic effects of design-based geometry variations on a low-pressure compressor
- Author
-
Torben Eggers, Hye Rim Kim, Simon L. Bittner, Joerg R. Seume, and Jens Friedrichs
- Subjects
Stator ,lcsh:Mechanical engineering and machinery ,Ultra-high bypass ratio (UHBR) engine ,Dewey Decimal Classification::600 | Technik::620 | Ingenieurwissenschaften und Maschinenbau ,Energy Engineering and Power Technology ,Aerospace Engineering ,Geometry ,02 engineering and technology ,Inflow ,Forced response ,Computational fluid dynamics ,01 natural sciences ,010305 fluids & plasmas ,law.invention ,0203 mechanical engineering ,law ,0103 physical sciences ,lcsh:TJ1-1570 ,Bypass ratio ,Aeroelasticity ,Physics ,020301 aerospace & aeronautics ,business.industry ,Mechanical Engineering ,Aerodynamics ,Dewey Decimal Classification::600 | Technik ,Turbofan ,Low-pressure compressor (LPC) ,ddc:620 ,business ,Gas compressor ,ddc:600 - Abstract
In modern aircraft engines, the low-pressure compressor (LPC) is subjected to a flow characterized by strong wakes and secondary flows from the upstream fan. This concerns ultra-high bypass ratio (UHBR) turbofan engines, in particular. This paper presents the aerodynamic and aeroelastic sensitivities of parametric variations on the LPC, driven by the design considerations in the upstream fan. The goal of this investigation was to determine the influence of design-based geometry parameter variations on the LPC performance under realistic inlet flow distributions and the presence of an s-duct. Aerodynamic simulations are conducted at the design and off-design operating points with the fan outflow as the inlet boundary conditions. Based on the aerodynamic results, time-linearized unsteady simulations are conducted to evaluate the vibration amplitude at the resonance operating points. First, the bypass ratio is varied by reducing the channel height of the LPC. The LPC efficiency decreases by up to 1.7% due to the increase in blockage of the core flow. The forced response amplitude of the rotor decreases with increasing bypass ratio due to increased aerodynamic damping. Secondly, the fan cavity leakage flow is considered as it directly affects the near hub fan flow and thus the inflow of the LPC. This results in an increased total-pressure loss for the s-duct due to mixing losses. The additional mixing redistributes the flow at the s-duct exit leading to a total-pressure loss reduction of 4.3% in the first rotor at design point. This effect is altered at off-design conditions. The vibration amplitude at low speed resonance points is increased by 19% for the first torsion and 26% for second bending. Thirdly, sweep and lean are applied to the inlet guide vane (IGV) upstream of the LPC. Despite the s-duct and the variable inlet guide vane (VIGV) affecting the flow, the three-dimensional blade design achieves aerodynamic and aeroelastic improvements of rotor 1 at off-design. The total-pressure loss reduces by up to 18% and the resonance amplitude more than 10%. Only negligible improvements for rotor 1 are present at the design point. In a fourth step, the influence of axial gap size between the stator and the rotor rows in the LPC is examined in the range of small variations which shows no distinct aerodynamic and aeroelastic sensitivities. This finding not only supports previous studies, but it also suggests a correlation between mode shapes and locally increased excitaion with increasing axial gap size. As a result, potential design improvements in future fan-compressor design are suggested.
- Published
- 2020
27. An in-silico study examining the induction of apoptosis by Cryptotanshinone in metastatic melanoma cell lines
- Author
-
Radhika Saraf, Rosana Lopes, Aniruddha Datta, Chao Sima, Michael L. Bittner, and Jianping Hua
- Subjects
0301 basic medicine ,Cancer Research ,Programmed cell death ,Apoptosis ,Cryptotanshinone ,Models, Biological ,lcsh:RC254-282 ,Boolean networks ,Biological pathway ,03 medical and health sciences ,0302 clinical medicine ,Cell Line, Tumor ,Genetics ,medicine ,Humans ,Computer Simulation ,STAT3 ,Melanoma ,biology ,Stat3 ,Gene Expression Profiling ,NF-kappa B ,Computational Biology ,Reproducibility of Results ,Cancer ,Phenanthrenes ,medicine.disease ,lcsh:Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,Mitochondria ,3. Good health ,030104 developmental biology ,Oncology ,030220 oncology & carcinogenesis ,Cancer cell ,biology.protein ,Cancer research ,Skin cancer ,Transcriptome ,Algorithms ,Biomarkers ,Trail ,Drugs, Chinese Herbal ,Signal Transduction ,Research Article - Abstract
Background Metastatic melanoma is an aggressive form of skin cancer that evades various anti-cancer treatments including surgery, radio-,immuno- and chemo-therapy. TRAIL-induced apoptosis is a desirable method to treat melanoma since, unlike other treatments, it does not harm non-cancerous cells. The pro-inflammatory response to melanoma by nF κB and STAT3 pathways makes the cancer cells resist TRAIL-induced apoptosis. We show that due to to its dual action on DR5, a death receptor for TRAIL and on STAT3, Cryptotanshinone can be used to increase sensitivity to TRAIL. Methods The development of chemoresistance and invasive properties in melanoma cells involves several biological pathways. The key components of these pathways are represented as a Boolean network with multiple inputs and multiple outputs. Results The possible mutations in genes that can lead to cancer are captured by faults in the combinatorial circuit and the model is used to theoretically predict the effectiveness of Cryptotanshinone for inducing apoptosis in melanoma cell lines. This prediction is experimentally validated by showing that Cryptotanshinone can cause enhanced cell death in A375 melanoma cells. Conclusion The results presented in this paper facilitate a better understanding of melanoma drug resistance. Furthermore, this framework can be used to detect additional drug intervention points in the pathway that could amplify the action of Cryptotanshinone. Electronic supplementary material The online version of this article (10.1186/s12885-018-4756-0) contains supplementary material, which is available to authorized users.
- Published
- 2018
28. Epifluorescent imaging study of the effect of anti-diabetic drug metformin on colorectal cancer cell lines in vitro
- Author
-
Michael L. Bittner, Priyadharshini S. Venkatasubramani, Aniruddha Datta, Sima C, Cypert M, and Jianping Hua
- Subjects
Drug ,Oncology ,medicine.medical_specialty ,Colorectal cancer ,business.industry ,media_common.quotation_subject ,lcsh:R ,lcsh:Medicine ,Imaging study ,medicine.disease ,In vitro ,3. Good health ,Metformin ,Cell culture ,Internal medicine ,medicine ,high-content imaging ,metformin ,diabetes ,colon cancer ,cancer metabolism ,cell death ,business ,media_common ,medicine.drug - Abstract
Metformin, a widely used anti-diabetic drug, has recently been associated with inhibition of cell proliferation in multiple cancers. However, it is not clear if the reduction in proliferation on treatment with metformin is a result of cell death or slowdown in the rate of growth of cancer cells, because cell viability assays measure only the number of cells at the beginning and end of the experiment. The aim of this study is to utilize a fluorescent imaging technique to directly follow cell death overtime in order to investigate the effect of metformin on colorectal cancer cells HCT116 and SW480. Epifluorescent imaging analysis carried out using ImageXpress Micro XLS High-Content Imaging System show that there is no significant change in cell death observed in the cancer cell lines, as compared to the control, over multiple closely spaced time points, suggesting that metformin in pharmacological doses may not be an effective inducer of cell death in these colon cancer cell lines.
- Published
- 2017
29. Assessing Combinational Drug Efficacy in Cancer Cells by Using Image-based Dynamic Response Analysis
- Author
-
Milana Cypert, Michael L. Bittner, Jeffrey M. Trent, Jianping Hua, Chao Sima, Heather Wilson-Robles, Edward R. Dougherty, and Tasha Miller
- Subjects
0301 basic medicine ,Drug ,Cancer Research ,Computer science ,media_common.quotation_subject ,drug response ,Translational research ,Drug action ,Computational biology ,Bioinformatics ,lcsh:RC254-282 ,Efficacy ,03 medical and health sciences ,0302 clinical medicine ,synergism ,cell imaging ,media_common ,Original Research ,dynamics ,Drug interaction ,lcsh:Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,combinational drug ,030104 developmental biology ,Oncology ,030220 oncology & carcinogenesis ,Informatics ,Drug delivery ,Cancer cell - Abstract
The landscape of translational research has been shifting toward drug combination therapies. Pairing of drugs allows for more types of drug interaction with cells. In order to accurately and comprehensively assess combinational drug efficacy, analytical methods capable of recognizing these alternative reactions will be required to prioritize those drug candidates having better chances of delivering appreciable therapeutic benefits. Traditional efficacy measures are primarily based on the “extent” of drug inhibition, which is the percentage of cells being killed after drug exposure. Here, we introduce a second dimension of evaluation criterion, speed of killing, based on a live cell imaging assay. This dynamic response trajectory approach takes advantage of both “extent” and “speed” information and uncovers synergisms that would otherwise be missed, while also generating hypotheses regarding important mechanistic modes of drug action.
- Published
- 2016
30. High-Content Assay Multiplexing for Toxicity Screening in Induced Pluripotent Stem Cell-Derived Cardiomyocytes and Hepatocytes
- Author
-
Oksana Sirenko, Yasuhiro Iwata, Michael L. Bittner, Ivan Rusyn, and Fabian A. Grimm
- Subjects
Cell Survival ,Induced Pluripotent Stem Cells ,Cell ,Drug Evaluation, Preclinical ,Pharmacology ,Biology ,Receptors, G-Protein-Coupled ,In vivo ,Toxicity Tests ,Drug Discovery ,High-Throughput Screening Assays ,Calcium flux ,medicine ,Humans ,Myocyte ,Myocytes, Cardiac ,Induced pluripotent stem cell ,Cells, Cultured ,Dose-Response Relationship, Drug ,Original Articles ,In vitro ,Cell biology ,medicine.anatomical_structure ,Doxorubicin ,Hepatocytes ,Molecular Medicine ,Reactive Oxygen Species ,Intracellular - Abstract
Cell-based high-content screening (HCS) assays have become an increasingly attractive alternative to traditional in vitro and in vivo testing in pharmaceutical drug development and toxicological safety assessment. The time- and cost-effectiveness of HCS assays, combined with the organotypic nature of human induced pluripotent stem cell (iPSC)-derived cells, open new opportunities to employ physiologically relevant in vitro model systems to improve screening for potential chemical hazards. In this study, we used two human iPSC types, cardiomyocytes and hepatocytes, to test various high-content and molecular assay combinations for their applicability in a multiparametric screening format. Effects on cardiomyocyte beat frequency were characterized by calcium flux measurements for up to 90 min. Subsequent correlation with intracellular cAMP levels was used to determine if the effects on cardiac physiology were G-protein-coupled receptor dependent. In addition, we utilized high-content cell imaging to simultaneously determine cell viability, mitochondrial integrity, and reactive oxygen species (ROS) formation in both cell types. Kinetic analysis indicated that ROS formation is best detectable 30 min following initial treatment, whereas cytotoxic effects were most stable after 24 h. For hepatocytes, high-content imaging was also used to evaluate cytotoxicity and cytoskeletal integrity, as well as mitochondrial integrity and the potential for lipid accumulation. Lipid accumulation, a marker for hepatic steatosis, was most reliably detected 48 h following treatment with test compounds. Overall, our results demonstrate how a compendium of assays can be utilized for quantitative screening of chemical effects in iPSC cardiomyocytes and hepatocytes and enable rapid and cost-efficient multidimensional biological profiling of toxicity.
- Published
- 2015
31. P-02-80 Over 1,000 No Scalpel, No Needle Vasectomies- Single Surgeon Experience
- Author
-
L. Bittner and L. Zamecnik
- Subjects
Psychiatry and Mental health ,medicine.medical_specialty ,Endocrinology ,Reproductive Medicine ,business.industry ,Urology ,Endocrinology, Diabetes and Metabolism ,General surgery ,medicine ,business ,Single surgeon - Published
- 2020
32. A Bayesian approach to determine the composition of heterogeneous cancer tissue
- Author
-
Chao Sima, Anwoy Kumar Mohanty, Ashish Katiyar, Jianping Hua, Rosana Lopes, Michael L. Bittner, and Aniruddha Datta
- Subjects
0301 basic medicine ,Computer science ,Colorectal cancer ,Cell Count ,computer.software_genre ,Biochemistry ,Metastasis ,0302 clinical medicine ,Structural Biology ,Neoplasms ,Econometrics ,lcsh:QH301-705.5 ,Metropolis algorithm ,0303 health sciences ,Applied Mathematics ,Melanoma ,3. Good health ,Computer Science Applications ,030220 oncology & carcinogenesis ,lcsh:R858-859.7 ,Data mining ,Algorithms ,Kernel density estimation ,Cancer tissue heterogeneity ,Bayesian probability ,Antineoplastic Agents ,Computational biology ,lcsh:Computer applications to medicine. Medical informatics ,Bayesian inference ,Synthetic data ,03 medical and health sciences ,Tissue heterogeneity ,Cell Line, Tumor ,medicine ,Humans ,Computer Simulation ,Molecular Biology ,030304 developmental biology ,Probability ,Sirolimus ,Research ,Experimental data ,Cancer ,Bayes Theorem ,Lapatinib ,medicine.disease ,Bayesian modeling ,030104 developmental biology ,lcsh:Biology (General) ,Cell culture ,Cancer cell ,computer - Abstract
Background Cancer Tissue Heterogeneity is an important consideration in cancer research as it can give insights into the causes and progression of cancer. It is known to play a significant role in cancer cell survival, growth and metastasis. Determining the compositional breakup of a heterogeneous cancer tissue can also help address the therapeutic challenges posed by heterogeneity. This necessitates a low cost, scalable algorithm to address the challenge of accurate estimation of the composition of a heterogeneous cancer tissue. Methods In this paper, we propose an algorithm to tackle this problem by utilizing the data of accurate, but high cost, single cell line cell-by-cell observation methods in low cost aggregate observation method for heterogeneous cancer cell mixtures to obtain their composition in a Bayesian framework. Results The algorithm is analyzed and validated using synthetic data and experimental data. The experimental data is obtained from mixtures of three separate human cancer cell lines, HCT116 (Colorectal carcinoma), A2058 (Melanoma) and SW480 (Colorectal carcinoma). Conclusion The algorithm provides a low cost framework to determine the composition of heterogeneous cancer tissue which is a crucial aspect in cancer research.
- Published
- 2018
33. P5337Predictors and case fatality rate of perioperative major cardiovascular events in cardiac patients undergoing non-cardiac surgery
- Author
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L. Bittner, Jiří Knot, Petr Widimsky, Jiri Jarkovsky, L. Havluj, Robert Gürlich, R. Grill, V. Dzupa, M. Ondrakova, R. Bartoska, and Zuzana Motovska
- Subjects
business.industry ,Anesthesia ,Non cardiac surgery ,Case fatality rate ,Medicine ,Perioperative ,Cardiology and Cardiovascular Medicine ,business - Published
- 2017
34. Mcl-1 Mediates TWEAK/Fn14-Induced Non–Small Cell Lung Cancer Survival and Therapeutic Response
- Author
-
Ryan Lena, Timothy G. Whitsett, Ian T. Mathews, Janine LoBello, Nhan L. Tran, William E. Pierceall, Michael H. Cardone, Glen J. Weiss, Michael L. Bittner, and Chao Sima
- Subjects
Cancer Research ,Lung Neoplasms ,Cell Survival ,medicine.drug_class ,Adenocarcinoma of Lung ,Adenocarcinoma ,Biology ,Transfection ,Article ,Receptors, Tumor Necrosis Factor ,Tyrosine-kinase inhibitor ,Cell Line, Tumor ,Radioresistance ,medicine ,Humans ,MCL1 ,RNA, Small Interfering ,Lung cancer ,neoplasms ,Molecular Biology ,Cisplatin ,NF-kappa B ,Cancer ,medicine.disease ,respiratory tract diseases ,Proto-Oncogene Proteins c-bcl-2 ,Oncology ,TWEAK Receptor ,Cancer cell ,Cancer research ,Myeloid Cell Leukemia Sequence 1 Protein ,Signal Transduction ,medicine.drug - Abstract
Insensitivity to standard clinical interventions, including chemotherapy, radiotherapy, and tyrosine kinase inhibitor (TKI) treatment, remains a substantial hindrance towards improving the prognosis of patients with non–small cell lung cancer (NSCLC). The molecular mechanism of therapeutic resistance remains poorly understood. The TNF-like weak inducer of apoptosis (TWEAK)–FGF-inducible 14 (TNFRSF12A/Fn14) signaling axis is known to promote cancer cell survival via NF-κB activation and the upregulation of prosurvival Bcl-2 family members. Here, a role was determined for TWEAK–Fn14 prosurvival signaling in NSCLC through the upregulation of myeloid cell leukemia sequence 1 (MCL1/Mcl-1). Mcl-1 expression significantly correlated with Fn14 expression, advanced NSCLC tumor stage, and poor patient prognosis in human primary NSCLC tumors. TWEAK stimulation of NSCLC cells induced NF-κB–dependent Mcl-1 protein expression and conferred Mcl-1–dependent chemo- and radioresistance. Depletion of Mcl-1 via siRNA or pharmacologic inhibition of Mcl-1, using EU-5148, sensitized TWEAK-treated NSCLC cells to cisplatin- or radiation-mediated inhibition of cell survival. Moreover, EU-5148 inhibited cell survival across a panel of NSCLC cell lines. In contrast, inhibition of Bcl-2/Bcl-xL function had minimal effect on suppressing TWEAK-induced cell survival. Collectively, these results position TWEAK–Fn14 signaling through Mcl-1 as a significant mechanism for NSCLC tumor cell survival and open new therapeutic avenues to abrogate the high mortality rate seen in NSCLC. Implications: The TWEAK–Fn14 signaling axis enhances lung cancer cell survival and therapeutic resistance through Mcl-1, positioning both TWEAK–Fn14 and Mcl-1 as therapeutic opportunities in lung cancer. Mol Cancer Res; 12(4); 550–9. ©2014 AACR.
- Published
- 2014
35. Evaluating Gene Set Enrichment Analysis Via a Hybrid Data Model
- Author
-
Michael L. Bittner, Jianping Hua, and Edward R. Dougherty
- Subjects
gene set enrichment analysis ,Cancer Research ,Ground truth ,Computer science ,computer.software_genre ,lcsh:Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,Data science ,lcsh:RC254-282 ,simulation study ,feature ranking ,Set (abstract data type) ,Data set ,data model ,Oncology ,Ranking ,Data model ,Resampling ,Data mining ,Focus (optics) ,computer ,Hybrid data ,Original Research - Abstract
Gene set enrichment analysis (GSA) methods have been widely adopted by biological labs to analyze data and generate hypotheses for validation. Most of the existing comparison studies focus on whether the existing GSA methods can produce accurate P-values; however, practitioners are often more concerned with the correct gene-set ranking generated by the methods. The ranking performance is closely related to two critical goals associated with GSA methods: the ability to reveal biological themes and ensuring reproducibility, especially for small-sample studies. We have conducted a comprehensive simulation study focusing on the ranking performance of seven representative GSA methods. We overcome the limitation on the availability of real data sets by creating hybrid data models from existing large data sets. To build the data model, we pick a master gene from the data set to form the ground truth and artificially generate the phenotype labels. Multiple hybrid data models can be constructed from one data set and multiple data sets of smaller sizes can be generated by resampling the original data set. This approach enables us to generate a large batch of data sets to check the ranking performance of GSA methods. Our simulation study reveals that for the proposed data model, the Q2 type GSA methods have in general better performance than other GSA methods and the global test has the most robust results. The properties of a data set play a critical role in the performance. For the data sets with highly connected genes, all GSA methods suffer significantly in performance.
- Published
- 2014
36. HP-08-004 Kinesiology Taping of Scrotum- an Update of 'Mummy wrap'
- Author
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L. Bittner, R. Valka, L. Zamecnik, and C. Bettocchi
- Subjects
Psychiatry and Mental health ,Endocrinology ,medicine.anatomical_structure ,Reproductive Medicine ,Kinesiology ,business.industry ,Urology ,Endocrinology, Diabetes and Metabolism ,Scrotum ,medicine ,Anatomy ,business - Published
- 2019
37. Use of Yeast Lysate in Women with Recurrent Vulvovaginal Candidiasis
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V. Vrzal, J. Nepereny, and L. Bittner
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biology ,business.industry ,Immunology ,Pharmaceutical Science ,biology.organism_classification ,Corpus albicans ,Propionibacterium acnes ,Immune system ,Infectious Diseases ,Immunity ,vaccine ,antibody ,Humoral immunity ,Drug Discovery ,vulvovaginal candidiasis ,candida ,medicine ,biology.protein ,Itching ,Recurrent vulvovaginal candidiasis ,medicine.symptom ,Antibody ,business - Abstract
Vulvovaginal candidiasis (VVC) affects a significant number of women, especially in working age. In an estimated 75% of women an episode of acute vulvovaginal candidiasis occurs during lifetime and another 5–10% of women develop recurrent vulvovaginal candidiasis (RVVC). This is mainly characterized by intense burning, itching, pain, abnormal discharge, dyspareunia. Immune response to candidiasis is both cellular (CMI) (natural protection mechanisms) and humoral (antibody production). Understanding the principles of immunity in candidiasis is also important for development of candida vaccines.CANDIVAC contains lyophilized Candida lysate (C. albicans, C. krusei, C. glabrata) together with immunostimulatory bacterial strain of Propionibacterium acnes. The product is taken orally in capsules for 10 days followed by a 20-day pause. It is administered for 3 to 6 months. The product has been tested in a total of 75 women at the age of 18–45 years. In these women at least 4 episodes of vulvovaginal candidiasis have been microscopically or laboratory diagnosed during the last 12 months. Following CANDIVAC administration, statistically significant changes occurred in the evaluation of subjective and some objective criteria. The most important marker of product efficiency is a significant reduction in recurrence compared to the recent state. This criterion has a fundamental importance in patient satisfaction. Before medication the patients suffered from at least 4 attacks, while after medication an attack occurred in only 31% of women and more than 2 attacks in only 3% of treated women.Compromised balance of immune system plays a major role in recurrent vulvovaginal candidiasis. Specific oral product CANDIVAC, prepared from the most common strains of yeast infections, supports immune mechanisms, ensuring resistance of the human organism against yeasts. Its administration significantly prolongs remission, leads to a reduction in application of antimycotics and also changes properties of cellular and humoral immunity in medicated patients.
- Published
- 2015
- Full Text
- View/download PDF
38. Systems biology for organotypic cell cultures
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Andre Kleensang, Miyoung Yoon, Michael L. Bittner, Scott S. Auerbach, Florian Martin, Sonia Grego, Edward R. Dougherty, Michael N J Liebman, Guilin Gary Qiao, Timothy R. Fennell, Elizabeth A. Maull, Philip C. Cooley, Ajit Dash, Susan Sumner, Sreenivasa Ramaiahgari, Francis J. Alexander, Jason Paragas, Brian T. Hawkins, Stephen S. Ferguson, Warren Casey, Anthony J. Hickey, and Brian R. Berridge
- Subjects
0301 basic medicine ,Systems biology ,Cell Culture Techniques ,Genomics ,Computational biology ,Biology ,Animal Testing Alternatives ,Risk Assessment ,Hazardous Substances ,03 medical and health sciences ,Lab-On-A-Chip Devices ,Animals ,Humans ,Computer Simulation ,Organism ,Pharmacology ,Biological data ,Computational model ,Systems Biology ,General Medicine ,Multiscale modeling ,Data science ,Medical Laboratory Technology ,Multicellular organism ,030104 developmental biology ,Systems pharmacology - Abstract
Translating in vitro biological data into actionable information related to human health holds the potential to improve disease treatment and risk assessment of chemical exposures. While genomics has identified regulatory pathways at the cellular level, translation to the organism level requires a multiscale approach accounting for intra-cellular regulation, inter-cellular interaction, and tissue/organ-level effects. Tissue-level effects can now be probed in vitro thanks to recently developed systems of three-dimensional (3D), multicellular, "organotypic" cell cultures, which mimic functional responses of living tissue. However, there remains a knowledge gap regarding interactions across different biological scales, complicating accurate prediction of health outcomes from molecular/genomic data and tissue responses. Systems biology aims at mathematical modeling of complex, non-linear biological systems. We propose to apply a systems biology approach to achieve a computational representation of tissue-level physiological responses by integrating empirical data derived from organotypic culture systems with computational models of intracellular pathways to better predict human responses. Successful implementation of this integrated approach will provide a powerful tool for faster, more accurate and cost-effective screening of potential toxicants and therapeutics. On September 11, 2015, an interdisciplinary group of scientists, engineers, and clinicians gathered for a workshop in Research Triangle Park, North Carolina, to discuss this ambitious goal. Participants represented laboratory-based and computational modeling approaches to pharmacology and toxicology, as well as the pharmaceutical industry, government, non-profits, and academia. Discussions focused on identifying critical system perturbations to model, the computational tools required, and the experimental approaches best suited to generating key data.
- Published
- 2016
39. Newton, Laplace, and The Epistemology of Systems Biology
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Michael L. Bittner and Edward R. Dougherty
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Cancer Research ,Laplace transform ,Computer science ,Systems biology ,epistemology ,Clinical science ,systems biology ,Bioinformatics ,lcsh:Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,lcsh:RC254-282 ,Celestial mechanics ,Development (topology) ,Oncology ,Systems theory ,Perspective ,Calculus ,cancer ,Cancer gene ,Medical journal ,control - Abstract
For science, theoretical or applied, to significantly advance, researchers must use the most appropriate mathematical methods. A century and a half elapsed between Newton's development of the calculus and Laplace's development of celestial mechanics. One cannot imagine the latter without the former. Today, more than three-quarters of a century has elapsed since the birth of stochastic systems theory. This article provides a perspective on the utilization of systems theory as the proper vehicle for the development of systems biology and its application to complex regulatory diseases such as cancer.
- Published
- 2012
40. Dynamical modeling of uncertain interaction-based genomic networks
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Michael L. Bittner, Jianping Hua, Edward R. Dougherty, and Daniel N. Mohsenizadeh
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Models, Molecular ,Biological data ,Dynamical modeling ,Process (engineering) ,Computer science ,Applied Mathematics ,Node (networking) ,Uncertainty ,Genomics ,Molecular Dynamics Simulation ,Dynamical model ,Network dynamics ,computer.software_genre ,Uncertain networks ,Biochemistry ,Data science ,Computer Science Applications ,Molecular dynamics ,Proceedings ,Algorithm design ,Structural Biology ,Data mining ,Molecular Biology ,computer - Abstract
Background Most dynamical models for genomic networks are built upon two current methodologies, one process-based and the other based on Boolean-type networks. Both are problematic when it comes to experimental design purposes in the laboratory. The first approach requires a comprehensive knowledge of the parameters involved in all biological processes a priori, whereas the results from the second method may not have a biological correspondence and thus cannot be tested in the laboratory. Moreover, the current methods cannot readily utilize existing curated knowledge databases and do not consider uncertainty in the knowledge. Therefore, a new methodology is needed that can generate a dynamical model based on available biological data, assuming uncertainty, while the results from experimental design can be examined in the laboratory. Results We propose a new methodology for dynamical modeling of genomic networks that can utilize the interaction knowledge provided in public databases. The model assigns discrete states for physical entities, sets priorities among interactions based on information provided in the database, and updates each interaction based on associated node states. Whenever uncertainty in dynamics arises, it explores all possible outcomes. By using the proposed model, biologists can study regulation networks that are too complex for manual analysis. Conclusions The proposed approach can be effectively used for constructing dynamical models of interaction-based genomic networks without requiring a complete knowledge of all parameters affecting the network dynamics, and thus based on a small set of available data.
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- 2015
41. Characterization of Drug Efficacy Regions Based on Dosage and Frequency Schedules
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Michael L. Bittner, Xiangfang Li, Lijun Qian, and Edward R. Dougherty
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Drug ,Mathematical optimization ,Dose ,media_common.quotation_subject ,Biomedical Engineering ,Pharmacology ,Models, Biological ,Drug Administration Schedule ,Efficacy ,Pharmacokinetics ,Humans ,Medicine ,Computer Simulation ,Gene Regulatory Networks ,Drug effect ,media_common ,Dose-Response Relationship, Drug ,business.industry ,Computational Biology ,Reproducibility of Results ,Regimen ,Pharmaceutical Preparations ,Hybrid system ,Pharmacodynamics ,business ,Algorithms - Abstract
This paper proposes a framework to study the drug effect at the molecular level in order to address the following question of current interest in the drug community: Given a fixed total delivered drug, which is better, frequent small or infrequent large drug dosages? A hybrid system model is proposed to link the drug's pharmacokinetic and pharmacodynamic information, and allows the drug effects for different dosages and treatment schedules to be compared. A hybrid model facilitates the modeling of continuous quantitative changes that leads to discrete transitions. An optimal dosage-frequency regimen and the necessary and sufficient conditions for the drug to be effective are obtained analytically when the drug is designed to control a target gene. Then, we extend the analysis to the case where the target gene is part of a genetic regulatory network. A crucial observation is that there exists a "sweet spot," defined as the "drug efficacy region (DER)" in this paper, for certain dosage and frequency arrangements given the total delivered drug. This paper quantifies the therapeutic benefits of dosage regimen lying within the DER. Simulations are performed using MATLAB/SIMULINK to validate the analytical results.
- Published
- 2011
42. Characterizing Memory Allocation Strategies in Transsaccadic Integration
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Melchi M. Michel and Jennifer L. Bittner
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Ophthalmology ,Computer science ,Distributed computing ,Sensory Systems - Published
- 2018
43. Failure to Recover to Baseline Pulmonary Function after Cystic Fibrosis Pulmonary Exacerbation
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Margaret Rosenfeld, Don B. Sanders, Gregory J. Redding, Christopher H. Goss, Rachel C. L. Bittner, and Lucas R. Hoffman
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Adult ,Male ,Pulmonary and Respiratory Medicine ,Spirometry ,medicine.medical_specialty ,Adolescent ,Cystic Fibrosis ,Critical Care and Intensive Care Medicine ,Cystic fibrosis ,Pulmonary function testing ,Young Adult ,Risk Factors ,Forced Expiratory Volume ,Internal medicine ,Intensive care ,Pulmonary fibrosis ,Humans ,Medicine ,Child ,Infusions, Intravenous ,Retrospective Studies ,medicine.diagnostic_test ,business.industry ,Respiratory disease ,B. Cystic Fibrosis ,Retrospective cohort study ,respiratory system ,medicine.disease ,Anti-Bacterial Agents ,respiratory tract diseases ,Surgery ,Logistic Models ,Treatment Outcome ,Disease Progression ,Female ,business ,Cohort study - Abstract
Patients with cystic fibrosis periodically experience pulmonary exacerbations. Previous studies have noted that some patients' lung function (FEV(1)) does not improve with treatment.To determine the proportion of patients treated for a pulmonary exacerbation that does not recover to spirometric baseline, and to identify factors associated with the failure to recover to spirometric baseline.Cohort study using the Cystic Fibrosis Foundation Patient Registry from 2003-2006. We randomly selected one pulmonary exacerbation treated with intravenous antibiotics per patient and compared the best FEV(1) in the 3 months after treatment with the best FEV(1) in the 6 months before treatment. Recovery to baseline was defined as any FEV(1) in the 3 months after treatment that was greater than or equal to 90% of the baseline FEV(1). Multivariable logistic regression was used to estimate associations with the failure to recover to baseline FEV(1).Of 8,479 pulmonary exacerbations, 25% failed to recover to baseline FEV(1). A higher risk of failing to recover to baseline was associated with female sex; pancreatic insufficiency; being undernourished; Medicaid insurance; persistent infection with Pseudomonas aeruginosa, Burkholderia cepacia complex, or methicillin-resistant Staphylococcus aureus; allergic bronchopulmonary aspergillosis; a longer time since baseline spirometric assessment; and a larger drop in FEV(1) from baseline to treatment initiation.For a randomly selected pulmonary exacerbation, 25% of patients' pulmonary function did not recover to baseline after treatment with intravenous antibiotics. We identified factors associated with the failure to recover to baseline, allowing clinicians to identify patients who may benefit from closer monitoring and more aggressive treatment.
- Published
- 2010
44. Performance of rheumatoid arthritis disease activity measures and juvenile arthritis disease activity scores in polyarticular-course juvenile idiopathic arthritis: Analysis of their ability to classify the American College of Rheumatology pediatric measur
- Author
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Nora G. Singer, Rachel C. L. Bittner, Tuhina Neogi, Carol A. Wallace, and Sarah Ringold
- Subjects
musculoskeletal diseases ,medicine.medical_specialty ,Arthritis ,Pediatrics ,Arthritis, Rheumatoid ,Juvenile Arthritis Disease Activity Score ,Rheumatology ,Internal medicine ,Outcome Assessment, Health Care ,Humans ,Medicine ,Clinical significance ,Child ,skin and connective tissue diseases ,business.industry ,Research ,Antibodies, Monoclonal ,medicine.disease ,Arthritis, Juvenile ,Infliximab ,Treatment Outcome ,ROC Curve ,Rheumatoid arthritis ,Cohort ,Physical therapy ,Joints ,business ,Juvenile rheumatoid arthritis ,medicine.drug - Abstract
Objective To measure the abilities of the continuous measures of disease activity used in rheumatoid arthritis (RA) and the 3 versions of the Juvenile Arthritis Disease Activity Score (JADAS; based upon 10-, 27-, and 71-joint counts) to accurately classify the American College of Rheumatology (ACR) pediatric measures of response, flare, and inactive disease in polyarticular-course juvenile idiopathic arthritis (JIA). Methods We conducted a secondary analysis of a randomized trial of infliximab in polyarticular-course JIA. Disease activity was calculated at baseline and weeks 14, 28, and 52 using the Disease Activity Score (DAS), DAS in 28 joints, Simplified Disease Activity Index, Clinical Disease Activity Index, and JADAS. The ability of the RA measures and JADAS to classify each ACR pediatric measure, flare, and inactive disease was measured by areas under the receiver operating characteristic curve (AUCs). Positive predictive values (PPVs) for inactive disease were calculated. Results Data from 97 participants were available. The AUCs for the RA scores for each ACR pediatric measure were 0.73–0.89. The AUCs of the JADAS for the ACR pediatric measures were 0.75–0.92. The PPVs of the RA scores for inactive disease were 0.33–0.67. The PPVs of the JADAS for inactive disease were each 0.93. Based on the RA and JADAS scores, the percentage of visits misclassified as inactive disease ranged from 7–67%. Conclusion The RA measures and JADAS versions showed acceptable to excellent ability to classify participants for each pediatric outcome measure, but the clinical significance of differences between AUCs for these scores could not be assessed. Misclassification of active disease versus inactive disease by the RA and JADAS scores was not uncommon in this cohort.
- Published
- 2010
45. BIODOSIMETRY ON SMALL BLOOD VOLUME USING GENE EXPRESSION ASSAY
- Author
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Sally A. Amundson, Frederic Zenhausern, Brigitte Paap, Ralf Lenigk, Muriel Brengues, Michael L. Bittner, Bruce Seligmann, and Ronald Korn
- Subjects
Epidemiology ,Fingerstick ,Health, Toxicology and Mutagenesis ,Population ,Protein Array Analysis ,Biology ,Radiation Dosage ,Article ,Biodosimetry ,Gene expression ,Humans ,Radiology, Nuclear Medicine and imaging ,Radiation Injuries ,Radiometry ,education ,Whole blood ,education.field_of_study ,Gene Expression Profiling ,Microchemistry ,Nuclease protection assay ,Blood Proteins ,Equipment Design ,Molecular biology ,Blood proteins ,Equipment Failure Analysis ,Gene expression profiling ,Biological Assay ,Biomarkers ,Blood Chemical Analysis - Abstract
This paper reports the development of a biodosimetry device suitable for rapidly measuring expression levels of a low-density gene set that can define radiation exposure, dose and injury in a public health emergency. The platform comprises a set of 14 genes selected on the basis of their abundance and differential expression level in response to radiation from an expression profiling series measuring 41,000 transcripts. Gene expression is analyzed through direct signal amplification using a quantitative Nuclease Protection Assay (qNPA). This assay can be configured as either a high-throughput microplate assay or as a handheld detection device for individual point-of-care assays. Recently, we were able to successfully develop the qNPA platform to measure gene expression levels directly from human whole blood samples. The assay can be performed with volumes as small as 30 microL of whole blood, which is compatible with collection from a fingerstick. We analyzed in vitro irradiated blood samples with qNPA. The results revealed statistically significant discrimination between irradiated and non-irradiated samples. These results indicate that the qNPA platform combined with a gene profile based on a small number of genes is a valid test to measure biological radiation exposure. The scalability characteristics of the assay make it appropriate for population triage. This biodosimetry platform could also be used for personalized monitoring of radiotherapy treatments received by patients.
- Published
- 2010
46. Phenotype Classification Using Moment Features of Single-Cell Data
- Author
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Edward R. Dougherty, Seungchan Kim, Michael L. Bittner, Jianping Hua, and Chao Sima
- Subjects
0301 basic medicine ,Cancer Research ,Microarray ,Cell ,Gene regulatory network ,gene regulatory network ,020206 networking & telecommunications ,02 engineering and technology ,Computational biology ,Biology ,lcsh:Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,Classification ,single-cell data ,lcsh:RC254-282 ,Phenotype ,Moment (mathematics) ,03 medical and health sciences ,030104 developmental biology ,medicine.anatomical_structure ,Special Collection: Signal Processing Applications in Genomics ,Oncology ,Expression (architecture) ,0202 electrical engineering, electronic engineering, information engineering ,medicine ,moment features - Abstract
Features for standard expression microarray and RNA-Seq classification are expression averages over collections of cells. Single cell provides expression measurements for individual cells in a collection of cells from a particular tissue sample. Hence, it can yield feature vectors consisting of higher order and mixed moments. This article demonstrates the advantage of using these expression moments in cancer-related classification. We use synthetic data generated from 2 real networks, the mammalian cell cycle network and a melanoma-related pathway network, and real single-cell data generated via fluorescent protein reporters from 2 cell lines, HT-29 and HCT-116. The networks consist of hidden binary regulatory networks with Gaussian observations. The steady-state distributions of both the original and mutated networks are found, and data are drawn from these for moment-based classification using the mean, variance, skewness, and mixed moments. For the real data, we only observe 1 gene at a time, so that only the mean, variance, and skewness are considered, the analysis being done for 2 genes, EGFR and ERRB2. For the synthetic data, classification improves as we move from just the mean to mean, variance, and skewness and then to these plus the mixed moments. Comparisons are done with 3, 4, or 5 features, using feature selection. Sample size effects are considered. For the real data, we only consider mean, variance, and skewness, with results improving when the higher order moments are used as features.
- Published
- 2018
47. Comprehensive genomic characterization defines human glioblastoma genes and core pathways
- Author
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Sandy Aronson, Leslie Cope, Michael L. Bittner, Daniel C. Koboldt, Alex E. Lash, W. K. Alfred Yung, Margaret Morgan, Devin Absher, Carl F. Schaefer, Roger E. McLendon, Michael D. Prados, Josh Gould, Ju Han, Stacey Gabriel, Scott R. VandenBerg, Ilana Perna, Troy Shelton, Junyuan Wu, Sacha Scott, Steve Scherer, Michael J. T. O’Kelly, Li Ding, Erin Hickey, Elizabeth J. Thomson, Bahram Parvin, Kim D. Delehaunty, Gi Choi Yoon, Mark D. Robinson, Oliver Bogler, Darrell D. Bigner, Michael R. Reich, Jianhua Zhang, Robert S. Fulton, Allan H. Friedman, Tammi L. Vickery, Amita Aggarwal, Subhashree Madhavan, Liuda Ziaugra, Yuan Qi, Vandita Joshi, Eric Van Name, Jane Wilkinson, W. Ruprecht Wiedemeyer, Xiaoqi Shi, Richard A. Gibbs, Lynda Chin, Jessica Chen, Stefano Monti, Erwin G. Van Meir, John Ngai, Amy Hawkins, Elizabeth Lenkiewicz, Brad Ozenberger, Shannon Dorton, Georgia Ren, John N. Weinstein, Gena M. Mastrogianakis, Asif T. Chinwalla, Scott L. Carter, Nicholas D. Socci, Rachel Abbott, Gavin Sherlock, Lucinda Fulton, Hyun Soo Kim, Fei Pan, Magali Cavatore, Gabriele Alexe, Francis S. Collins, Narayanan Sathiamoorthy, Lakshmi Jakkula, Brian H. Dunford-Shore, Jireh Santibanez, Tom Mikkelsen, Huy V. Nguyen, Levi A. Garraway, Christopher A. Miller, Jinghui Zhang, Ken Chen, Timothy Fennell, Robert Sfeir, James A. Robinson, Alexey Stukalov, Richard K. Wilson, Matthew Meyerson, Daniel J. Weisenberger, Mi Yi Joo, Yevgeniy Antipin, Anna Lapuk, Gerald V. Fontenay, Nicolas Stransky, Adam B. Olshen, Elizabeth Purdom, Josh Korn, Huyen Dinh, Sai Balu, Victoria Wang, James G. Herman, Christie Kovar, Kristian Cibulskis, Tisha Chung, Agnes Viale, Paul T. Spellman, Supriya Gupta, Melissa Parkin, Peter J. Park, Maddy Wiechert, John W. Wallis, Peter W. Laird, Nikolaus Schultz, James D. Brooks, David Nassau, Jun Li, John R. Osborne, Anna D. Barker, Peter Fielding, Boris Reva, Karen Vranizan, D. Neil Hayes, Aleksandar Milosavljevic, Lawrence A. Donehower, Won Kong Sek, Daniela S. Gerhard, Otis Hall, Rameen Beroukhim, Audrey Southwick, George M. Weinstock, Chris Markovic, Roel G.W. Verhaak, David Van Den Berg, Joe W. Gray, Yanru Ren, Ethan Cerami, Yiming Zhu, Amrita Ray, Yonghong Xiao, Kristin G. Ardlie, William L. Gerald, Michael S. Lawrence, Gerald R. Fowler, Mark S. Guyer, Isaac S. Kohane, Kornel E. Schuebel, Mitchel S. Berger, Jeffrey J. Olson, Gary W. Swift, Lora Lewis, Sheri Sanders, Norman L. Lehman, Eric S. Lander, Robert Penny, Liliana Villafania, John G. Conboy, Ari B. Kahn, Henry Marr, Heidi S. Feiler, Lynn Nazareth, David J. Dooling, Katherine A. Hoadley, Alicia Hawes, Marc Ladanyi, Aniko Sabo, Wendy Winckler, Vivian Peng, Barbara A. Weir, Daniel J. Brat, Scott Morris, Carolyn C. Compton, Todd R. Golub, Scott Abbott, Michael D. McLellan, Jiqiang Yao, Shalini N. Jhangiani, Michael D. Topal, Michael C. Wendl, Gad Getz, Jun Yao, Derek Y. Chiang, Larry Feng, Steffen Durinck, David A. Wheeler, Yuzhu Tang, Benjamin Gross, Barry S. Taylor, Kenneth Aldape, Craig Pohl, Rick Meyer, Peter J. Good, Ling Lin, Elaine R. Mardis, Robert C. Onofrio, Jane Peterson, Stephen B. Baylin, Li-Xuan Qin, Andrew Cree, Cameron Brennan, Charles M. Perou, William Courtney, Omar Alvi, Donna M. Muzny, Joseph G. Vockley, Jill P. Mesirov, Yan Shi, Alexei Protopopov, Jim Vaught, Craig H. Mermel, Scott Mahan, Laetitia Borsu, Heather Schmidt, Jennifer Baldwin, Tracie L. Miner, Toby Bloom, David E. Larson, Leander Van Neste, Nicholas J. Wang, Kenneth H. Buetow, Raju Kucherlapati, Anthony San Lucas, Martin L. Ferguson, Terence P. Speed, Venkatraman E. Seshan, Debbie Beasley, Carrie Sougnez, Carrie A. Haipek, Richard M. Myers, Chris Sander, Qing Wang Wei, Jon G. Seidman, Rob Nicol, Manuel L. Gonzalez-Garay, Shin Leong, Shannon T. Brady, and University of Groningen
- Subjects
Male ,Models, Molecular ,DNA Repair ,Gene Dosage ,NEUROFIBROMATOSIS TYPE-1 ,MISMATCH REPAIR ,Phosphatidylinositol 3-Kinases ,0302 clinical medicine ,Genes, Tumor Suppressor ,DNA Modification Methylases ,Proneural Glioblastoma ,Aged, 80 and over ,Genetics ,0303 health sciences ,Neurofibromin 1 ,Multidisciplinary ,Brain Neoplasms ,NF1 GENE ,Genomics ,Middle Aged ,TUMORS ,ALKYLATING-AGENTS ,3. Good health ,Gene Expression Regulation, Neoplastic ,030220 oncology & carcinogenesis ,DNA methylation ,Female ,DNA mismatch repair ,Functional genomics ,Signal Transduction ,Adult ,Adolescent ,CELL-LINES ,Oncogenomics ,Biology ,Article ,03 medical and health sciences ,PIK3CA GENE ,Humans ,Epigenetics ,Gene ,Aged ,Retrospective Studies ,030304 developmental biology ,HIGH-FREQUENCY ,Genome, Human ,Tumor Suppressor Proteins ,SOMATIC MUTATIONS ,Genes, erbB-1 ,DNA Methylation ,Protein Structure, Tertiary ,MALIGNANT GLIOMAS ,DNA Repair Enzymes ,Mutation ,Glioblastoma - Abstract
Human cancer cells typically harbour multiple chromosomal aberrations, nucleotide substitutions and epigenetic modifications that drive malignant transformation. The Cancer Genome Atlas ( TCGA) pilot project aims to assess the value of large- scale multi- dimensional analysis of these molecular characteristics in human cancer and to provide the data rapidly to the research community. Here we report the interim integrative analysis of DNA copy number, gene expression and DNA methylation aberrations in 206 glioblastomas - the most common type of primary adult brain cancer - and nucleotide sequence aberrations in 91 of the 206 glioblastomas. This analysis provides new insights into the roles of ERBB2, NF1 and TP53, uncovers frequent mutations of the phosphatidylinositol- 3- OH kinase regulatory subunit gene PIK3R1, and provides a network view of the pathways altered in the development of glioblastoma. Furthermore, integration of mutation, DNA methylation and clinical treatment data reveals a link between MGMT promoter methylation and a hypermutator phenotype consequent to mismatch repair deficiency in treated glioblastomas, an observation with potential clinical implications. Together, these findings establish the feasibility and power of TCGA, demonstrating that it can rapidly expand knowledge of the molecular basis of cancer.
- Published
- 2008
48. Intrinsically Multivariate Predictive Genes
- Author
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Ronaldo Fumio Hashimoto, David Martins, Edward R. Dougherty, Ulisses Braga-Neto, and Michael L. Bittner
- Subjects
Multivariate statistics ,Normal conditions ,BIOINFORMÁTICA ,Computational biology ,Covariance ,Biology ,Joint probability distribution ,Signal Processing ,Statistics ,Predictive power ,Entropy (information theory) ,Electrical and Electronic Engineering ,Gene ,Biological network - Abstract
Canalizing genes possess such broad regulatory power, and their action sweeps across a such a wide swath of processes that the full set of affected genes are not highly correlated under normal conditions. When not active, the controlling gene will not be predictable to any significant degree by its subject genes, either alone or in groups, since their behavior will be highly varied relative to the inactive controlling gene. When the controlling gene is active, its behavior is not well predicted by any one of its targets, but can be very well predicted by groups of genes under its control. To investigate this question, we introduce in this paper the concept of intrinsically multivariate predictive (IMP) genes, and present a mathematical study of IMP in the context of binary genes with respect to the coefficient of determination (CoD), which measures the predictive power of a set of genes with respect to a target gene. A set of predictor genes is said to be IMP for a target gene if all properly contained subsets of the predictor set are bad predictors of the target but the full predictor set predicts the target with great accuracy. We show that logic of prediction, predictive power, covariance between predictors, and the entropy of the joint probability distribution of the predictors jointly affect the appearance of IMP genes. In particular, we show that high-predictive power, small covariance among predictors, a large entropy of the joint probability distribution of predictors, and certain logics, such as XOR in the 2-predictor case, are factors that favor the appearance of IMP. The IMP concept is applied to characterize the behavior of the gene DUSP1, which exhibits control over a central, process-integrating signaling pathway, thereby providing preliminary evidence that IMP can be used as a criterion for discovery of canalizing genes.
- Published
- 2008
49. Validation of Computational Methods in Genomics
- Author
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Hua Jianping, Edward R Doughtery, and Michael L. Bittner
- Subjects
Computer science ,Inference ,computer.software_genre ,Scientific modelling ,Article ,Salient ,Sample size determination ,Genetics ,Symbolic convergence theory ,Data mining ,Cluster analysis ,computer ,Classifier (UML) ,Genetics (clinical) ,Curse of dimensionality - Abstract
High-throughput technologies for genomics provide tens of thousands of genetic measurements, for instance, gene-expression measurements on microarrays, and the availability of these measurements has motivated the use of machine learning (inference) methods for classification, clustering, and gene networks. Generally, a design method will yield a model that satisfies some model constraints and fits the data in some manner. On the other hand, a scientific theory consists of two parts: (1) a mathematical model to characterize relations between variables, and (2) a set of relations between model variables and observables that are used to validate the model via predictive experiments. Although machine learning algorithms are constructed to hopefully produce valid scientific models, they do not ipso facto do so. In some cases, such as classifier estimation, there is a well-developed error theory that relates to model validity according to various statistical theorems, but in others such as clustering, there is a lack of understanding of the relationship between the learning algorithms and validation. The issue of validation is especially problematic in situations where the sample size is small in comparison with the dimensionality (number of variables), which is commonplace in genomics, because the convergence theory of learning algorithms is typically asymptotic and the algorithms often perform in counter-intuitive ways when used with samples that are small in relation to the number of variables. For translational genomics, validation is perhaps the most critical issue, because it is imperative that we understand the performance of a diagnostic or therapeutic procedure to be used in the clinic, and this performance relates directly to the validity of the model behind the procedure. This paper treats the validation issue as it appears in two classes of inference algorithms relating to genomics – classification and clustering. It formulates the problem and reviews salient results.
- Published
- 2007
50. A Robust Structural PGN Model for Control of Cell-Cycle Progression Stabilized by Negative Feedbacks
- Author
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Nestor Walter Trepode, Marco Dimas Gubitoso, Junior Barrera, Michael L. Bittner, Hugo A. Armelin, and Ronaldo Fumio Hashimoto
- Subjects
Statistics and Probability ,Computer science ,Systems biology ,0206 medical engineering ,02 engineering and technology ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,General ,Control (linguistics) ,030304 developmental biology ,Positive feedback ,Medicine(all) ,0303 health sciences ,business.industry ,Stochastic process ,Noise (signal processing) ,Probabilistic logic ,Robustness (evolution) ,Computer Science Applications ,Computational Mathematics ,Integrator ,Signal Processing ,Artificial intelligence ,business ,Biological system ,CICLO CELULAR ,020602 bioinformatics ,Research Article ,Computer Science(all) - Abstract
The cell division cycle comprises a sequence of phenomena controlled by a stable and robust genetic network. We applied a probabilistic genetic network (PGN) to construct a hypothetical model with a dynamical behavior displaying the degree of robustness typical of the biological cell cycle. The structure of our PGN model was inspired in well-established biological facts such as the existence of integrator subsystems, negative and positive feedback loops, and redundant signaling pathways. Our model represents genes interactions as stochastic processes and presents strong robustness in the presence of moderate noise and parameters fluctuations. A recently published deterministic yeast cell-cycle model does not perform as well as our PGN model, even upon moderate noise conditions. In addition, self stimulatory mechanisms can give our PGN model the possibility of having a pacemaker activity similar to the observed in the oscillatory embryonic cell cycle.
- Published
- 2007
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